#include <linux/sched.h>
#include <linux/pagemap.h>
#include <linux/writeback.h>
+#include <linux/blkdev.h>
+#include <linux/sort.h>
+#include "compat.h"
#include "hash.h"
#include "crc32c.h"
#include "ctree.h"
#include "locking.h"
#include "ref-cache.h"
-#define BLOCK_GROUP_DATA EXTENT_WRITEBACK
-#define BLOCK_GROUP_METADATA EXTENT_UPTODATE
-#define BLOCK_GROUP_SYSTEM EXTENT_NEW
+#define PENDING_EXTENT_INSERT 0
+#define PENDING_EXTENT_DELETE 1
+#define PENDING_BACKREF_UPDATE 2
-#define BLOCK_GROUP_DIRTY EXTENT_DIRTY
+struct pending_extent_op {
+ int type;
+ u64 bytenr;
+ u64 num_bytes;
+ u64 parent;
+ u64 orig_parent;
+ u64 generation;
+ u64 orig_generation;
+ int level;
+ struct list_head list;
+ int del;
+};
+
+static int finish_current_insert(struct btrfs_trans_handle *trans,
+ struct btrfs_root *extent_root, int all);
+static int del_pending_extents(struct btrfs_trans_handle *trans,
+ struct btrfs_root *extent_root, int all);
+static int pin_down_bytes(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ u64 bytenr, u64 num_bytes, int is_data);
+static int update_block_group(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ u64 bytenr, u64 num_bytes, int alloc,
+ int mark_free);
+
+static int do_chunk_alloc(struct btrfs_trans_handle *trans,
+ struct btrfs_root *extent_root, u64 alloc_bytes,
+ u64 flags, int force);
+
+static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
+{
+ return (cache->flags & bits) == bits;
+}
-static int finish_current_insert(struct btrfs_trans_handle *trans, struct
- btrfs_root *extent_root);
-static int del_pending_extents(struct btrfs_trans_handle *trans, struct
- btrfs_root *extent_root);
+/*
+ * this adds the block group to the fs_info rb tree for the block group
+ * cache
+ */
+static int btrfs_add_block_group_cache(struct btrfs_fs_info *info,
+ struct btrfs_block_group_cache *block_group)
+{
+ struct rb_node **p;
+ struct rb_node *parent = NULL;
+ struct btrfs_block_group_cache *cache;
+
+ spin_lock(&info->block_group_cache_lock);
+ p = &info->block_group_cache_tree.rb_node;
+
+ while (*p) {
+ parent = *p;
+ cache = rb_entry(parent, struct btrfs_block_group_cache,
+ cache_node);
+ if (block_group->key.objectid < cache->key.objectid) {
+ p = &(*p)->rb_left;
+ } else if (block_group->key.objectid > cache->key.objectid) {
+ p = &(*p)->rb_right;
+ } else {
+ spin_unlock(&info->block_group_cache_lock);
+ return -EEXIST;
+ }
+ }
+
+ rb_link_node(&block_group->cache_node, parent, p);
+ rb_insert_color(&block_group->cache_node,
+ &info->block_group_cache_tree);
+ spin_unlock(&info->block_group_cache_lock);
+
+ return 0;
+}
+
+/*
+ * This will return the block group at or after bytenr if contains is 0, else
+ * it will return the block group that contains the bytenr
+ */
static struct btrfs_block_group_cache *
-__btrfs_find_block_group(struct btrfs_root *root,
- struct btrfs_block_group_cache *hint,
- u64 search_start, int data, int owner);
+block_group_cache_tree_search(struct btrfs_fs_info *info, u64 bytenr,
+ int contains)
+{
+ struct btrfs_block_group_cache *cache, *ret = NULL;
+ struct rb_node *n;
+ u64 end, start;
-void maybe_lock_mutex(struct btrfs_root *root)
+ spin_lock(&info->block_group_cache_lock);
+ n = info->block_group_cache_tree.rb_node;
+
+ while (n) {
+ cache = rb_entry(n, struct btrfs_block_group_cache,
+ cache_node);
+ end = cache->key.objectid + cache->key.offset - 1;
+ start = cache->key.objectid;
+
+ if (bytenr < start) {
+ if (!contains && (!ret || start < ret->key.objectid))
+ ret = cache;
+ n = n->rb_left;
+ } else if (bytenr > start) {
+ if (contains && bytenr <= end) {
+ ret = cache;
+ break;
+ }
+ n = n->rb_right;
+ } else {
+ ret = cache;
+ break;
+ }
+ }
+ if (ret)
+ atomic_inc(&ret->count);
+ spin_unlock(&info->block_group_cache_lock);
+
+ return ret;
+}
+
+/*
+ * this is only called by cache_block_group, since we could have freed extents
+ * we need to check the pinned_extents for any extents that can't be used yet
+ * since their free space will be released as soon as the transaction commits.
+ */
+static int add_new_free_space(struct btrfs_block_group_cache *block_group,
+ struct btrfs_fs_info *info, u64 start, u64 end)
{
- if (root != root->fs_info->extent_root &&
- root != root->fs_info->chunk_root &&
- root != root->fs_info->dev_root) {
- mutex_lock(&root->fs_info->alloc_mutex);
+ u64 extent_start, extent_end, size;
+ int ret;
+
+ mutex_lock(&info->pinned_mutex);
+ while (start < end) {
+ ret = find_first_extent_bit(&info->pinned_extents, start,
+ &extent_start, &extent_end,
+ EXTENT_DIRTY);
+ if (ret)
+ break;
+
+ if (extent_start == start) {
+ start = extent_end + 1;
+ } else if (extent_start > start && extent_start < end) {
+ size = extent_start - start;
+ ret = btrfs_add_free_space(block_group, start,
+ size);
+ BUG_ON(ret);
+ start = extent_end + 1;
+ } else {
+ break;
+ }
+ }
+
+ if (start < end) {
+ size = end - start;
+ ret = btrfs_add_free_space(block_group, start, size);
+ BUG_ON(ret);
}
+ mutex_unlock(&info->pinned_mutex);
+
+ return 0;
}
-void maybe_unlock_mutex(struct btrfs_root *root)
+static int remove_sb_from_cache(struct btrfs_root *root,
+ struct btrfs_block_group_cache *cache)
{
- if (root != root->fs_info->extent_root &&
- root != root->fs_info->chunk_root &&
- root != root->fs_info->dev_root) {
- mutex_unlock(&root->fs_info->alloc_mutex);
+ u64 bytenr;
+ u64 *logical;
+ int stripe_len;
+ int i, nr, ret;
+
+ for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
+ bytenr = btrfs_sb_offset(i);
+ ret = btrfs_rmap_block(&root->fs_info->mapping_tree,
+ cache->key.objectid, bytenr, 0,
+ &logical, &nr, &stripe_len);
+ BUG_ON(ret);
+ while (nr--) {
+ btrfs_remove_free_space(cache, logical[nr],
+ stripe_len);
+ }
+ kfree(logical);
}
+ return 0;
}
static int cache_block_group(struct btrfs_root *root,
struct btrfs_block_group_cache *block_group)
{
struct btrfs_path *path;
- int ret;
+ int ret = 0;
struct btrfs_key key;
struct extent_buffer *leaf;
- struct extent_io_tree *free_space_cache;
int slot;
- u64 last = 0;
- u64 hole_size;
- u64 first_free;
- int found = 0;
+ u64 last;
if (!block_group)
return 0;
root = root->fs_info->extent_root;
- free_space_cache = &root->fs_info->free_space_cache;
if (block_group->cached)
return 0;
* skip the locking here
*/
path->skip_locking = 1;
- first_free = block_group->key.objectid;
- key.objectid = block_group->key.objectid;
+ last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET);
+ key.objectid = last;
key.offset = 0;
btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
if (ret < 0)
- return ret;
- ret = btrfs_previous_item(root, path, 0, BTRFS_EXTENT_ITEM_KEY);
- if (ret < 0)
- return ret;
- if (ret == 0) {
- leaf = path->nodes[0];
- btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
- if (key.objectid + key.offset > first_free)
- first_free = key.objectid + key.offset;
- }
- while(1) {
+ goto err;
+
+ while (1) {
leaf = path->nodes[0];
slot = path->slots[0];
if (slot >= btrfs_header_nritems(leaf)) {
ret = btrfs_next_leaf(root, path);
if (ret < 0)
goto err;
- if (ret == 0) {
+ if (ret == 0)
continue;
- } else {
+ else
break;
- }
}
btrfs_item_key_to_cpu(leaf, &key, slot);
- if (key.objectid < block_group->key.objectid) {
+ if (key.objectid < block_group->key.objectid)
goto next;
- }
+
if (key.objectid >= block_group->key.objectid +
- block_group->key.offset) {
+ block_group->key.offset)
break;
- }
if (btrfs_key_type(&key) == BTRFS_EXTENT_ITEM_KEY) {
- if (!found) {
- last = first_free;
- found = 1;
- }
- if (key.objectid > last) {
- hole_size = key.objectid - last;
- set_extent_dirty(free_space_cache, last,
- last + hole_size - 1,
- GFP_NOFS);
- }
+ add_new_free_space(block_group, root->fs_info, last,
+ key.objectid);
+
last = key.objectid + key.offset;
}
next:
path->slots[0]++;
}
- if (!found)
- last = first_free;
- if (block_group->key.objectid +
- block_group->key.offset > last) {
- hole_size = block_group->key.objectid +
- block_group->key.offset - last;
- set_extent_dirty(free_space_cache, last,
- last + hole_size - 1, GFP_NOFS);
- }
+ add_new_free_space(block_group, root->fs_info, last,
+ block_group->key.objectid +
+ block_group->key.offset);
+
+ remove_sb_from_cache(root, block_group);
block_group->cached = 1;
+ ret = 0;
err:
btrfs_free_path(path);
- return 0;
+ return ret;
}
-struct btrfs_block_group_cache *btrfs_lookup_first_block_group(struct
- btrfs_fs_info *info,
- u64 bytenr)
+/*
+ * return the block group that starts at or after bytenr
+ */
+static struct btrfs_block_group_cache *
+btrfs_lookup_first_block_group(struct btrfs_fs_info *info, u64 bytenr)
{
- struct extent_io_tree *block_group_cache;
- struct btrfs_block_group_cache *block_group = NULL;
- u64 ptr;
- u64 start;
- u64 end;
- int ret;
+ struct btrfs_block_group_cache *cache;
- bytenr = max_t(u64, bytenr,
- BTRFS_SUPER_INFO_OFFSET + BTRFS_SUPER_INFO_SIZE);
- block_group_cache = &info->block_group_cache;
- ret = find_first_extent_bit(block_group_cache,
- bytenr, &start, &end,
- BLOCK_GROUP_DATA | BLOCK_GROUP_METADATA |
- BLOCK_GROUP_SYSTEM);
- if (ret) {
- return NULL;
- }
- ret = get_state_private(block_group_cache, start, &ptr);
- if (ret)
- return NULL;
+ cache = block_group_cache_tree_search(info, bytenr, 0);
- block_group = (struct btrfs_block_group_cache *)(unsigned long)ptr;
- return block_group;
+ return cache;
}
-struct btrfs_block_group_cache *btrfs_lookup_block_group(struct
- btrfs_fs_info *info,
- u64 bytenr)
+/*
+ * return the block group that contains teh given bytenr
+ */
+struct btrfs_block_group_cache *btrfs_lookup_block_group(
+ struct btrfs_fs_info *info,
+ u64 bytenr)
{
- struct extent_io_tree *block_group_cache;
- struct btrfs_block_group_cache *block_group = NULL;
- u64 ptr;
- u64 start;
- u64 end;
- int ret;
+ struct btrfs_block_group_cache *cache;
- bytenr = max_t(u64, bytenr,
- BTRFS_SUPER_INFO_OFFSET + BTRFS_SUPER_INFO_SIZE);
- block_group_cache = &info->block_group_cache;
- ret = find_first_extent_bit(block_group_cache,
- bytenr, &start, &end,
- BLOCK_GROUP_DATA | BLOCK_GROUP_METADATA |
- BLOCK_GROUP_SYSTEM);
- if (ret) {
- return NULL;
- }
- ret = get_state_private(block_group_cache, start, &ptr);
- if (ret)
- return NULL;
+ cache = block_group_cache_tree_search(info, bytenr, 1);
- block_group = (struct btrfs_block_group_cache *)(unsigned long)ptr;
- if (block_group->key.objectid <= bytenr && bytenr <
- block_group->key.objectid + block_group->key.offset)
- return block_group;
- return NULL;
+ return cache;
}
-static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
+static inline void put_block_group(struct btrfs_block_group_cache *cache)
{
- return (cache->flags & bits) == bits;
+ if (atomic_dec_and_test(&cache->count))
+ kfree(cache);
}
-static int noinline find_search_start(struct btrfs_root *root,
- struct btrfs_block_group_cache **cache_ret,
- u64 *start_ret, u64 num, int data)
+static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
+ u64 flags)
{
- int ret;
- struct btrfs_block_group_cache *cache = *cache_ret;
- struct extent_io_tree *free_space_cache;
- struct extent_state *state;
- u64 last;
- u64 start = 0;
- u64 cache_miss = 0;
- u64 total_fs_bytes;
- u64 search_start = *start_ret;
- int wrapped = 0;
-
- WARN_ON(!mutex_is_locked(&root->fs_info->alloc_mutex));
- total_fs_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy);
- free_space_cache = &root->fs_info->free_space_cache;
-
- if (!cache)
- goto out;
-
-again:
- ret = cache_block_group(root, cache);
- if (ret) {
- goto out;
- }
-
- last = max(search_start, cache->key.objectid);
- if (!block_group_bits(cache, data) || cache->ro)
- goto new_group;
-
- spin_lock_irq(&free_space_cache->lock);
- state = find_first_extent_bit_state(free_space_cache, last, EXTENT_DIRTY);
- while(1) {
- if (!state) {
- if (!cache_miss)
- cache_miss = last;
- spin_unlock_irq(&free_space_cache->lock);
- goto new_group;
- }
-
- start = max(last, state->start);
- last = state->end + 1;
- if (last - start < num) {
- do {
- state = extent_state_next(state);
- } while(state && !(state->state & EXTENT_DIRTY));
- continue;
- }
- spin_unlock_irq(&free_space_cache->lock);
- if (cache->ro) {
- goto new_group;
- }
- if (start + num > cache->key.objectid + cache->key.offset)
- goto new_group;
- if (!block_group_bits(cache, data)) {
- printk("block group bits don't match %Lu %d\n", cache->flags, data);
- }
- *start_ret = start;
- return 0;
- }
-out:
- cache = btrfs_lookup_block_group(root->fs_info, search_start);
- if (!cache) {
- printk("Unable to find block group for %Lu\n", search_start);
- WARN_ON(1);
- }
- return -ENOSPC;
-
-new_group:
- last = cache->key.objectid + cache->key.offset;
-wrapped:
- cache = btrfs_lookup_first_block_group(root->fs_info, last);
- if (!cache || cache->key.objectid >= total_fs_bytes) {
-no_cache:
- if (!wrapped) {
- wrapped = 1;
- last = search_start;
- goto wrapped;
- }
- goto out;
- }
- if (cache_miss && !cache->cached) {
- cache_block_group(root, cache);
- last = cache_miss;
- cache = btrfs_lookup_first_block_group(root->fs_info, last);
+ struct list_head *head = &info->space_info;
+ struct btrfs_space_info *found;
+ list_for_each_entry(found, head, list) {
+ if (found->flags == flags)
+ return found;
}
- cache_miss = 0;
- cache = btrfs_find_block_group(root, cache, last, data, 0);
- if (!cache)
- goto no_cache;
- *cache_ret = cache;
- goto again;
+ return NULL;
}
static u64 div_factor(u64 num, int factor)
return num;
}
-static int block_group_state_bits(u64 flags)
-{
- int bits = 0;
- if (flags & BTRFS_BLOCK_GROUP_DATA)
- bits |= BLOCK_GROUP_DATA;
- if (flags & BTRFS_BLOCK_GROUP_METADATA)
- bits |= BLOCK_GROUP_METADATA;
- if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
- bits |= BLOCK_GROUP_SYSTEM;
- return bits;
-}
-
-static struct btrfs_block_group_cache *
-__btrfs_find_block_group(struct btrfs_root *root,
- struct btrfs_block_group_cache *hint,
- u64 search_start, int data, int owner)
+u64 btrfs_find_block_group(struct btrfs_root *root,
+ u64 search_start, u64 search_hint, int owner)
{
struct btrfs_block_group_cache *cache;
- struct extent_io_tree *block_group_cache;
- struct btrfs_block_group_cache *found_group = NULL;
- struct btrfs_fs_info *info = root->fs_info;
u64 used;
- u64 last = 0;
- u64 start;
- u64 end;
- u64 free_check;
- u64 ptr;
- int bit;
- int ret;
+ u64 last = max(search_hint, search_start);
+ u64 group_start = 0;
int full_search = 0;
- int factor = 10;
+ int factor = 9;
int wrapped = 0;
-
- block_group_cache = &info->block_group_cache;
-
- if (data & BTRFS_BLOCK_GROUP_METADATA)
- factor = 9;
-
- bit = block_group_state_bits(data);
-
- if (search_start) {
- struct btrfs_block_group_cache *shint;
- shint = btrfs_lookup_first_block_group(info, search_start);
- if (shint && block_group_bits(shint, data) && !shint->ro) {
- spin_lock(&shint->lock);
- used = btrfs_block_group_used(&shint->item);
- if (used + shint->pinned <
- div_factor(shint->key.offset, factor)) {
- spin_unlock(&shint->lock);
- return shint;
- }
- spin_unlock(&shint->lock);
- }
- }
- if (hint && !hint->ro && block_group_bits(hint, data)) {
- spin_lock(&hint->lock);
- used = btrfs_block_group_used(&hint->item);
- if (used + hint->pinned <
- div_factor(hint->key.offset, factor)) {
- spin_unlock(&hint->lock);
- return hint;
- }
- spin_unlock(&hint->lock);
- last = hint->key.objectid + hint->key.offset;
- } else {
- if (hint)
- last = max(hint->key.objectid, search_start);
- else
- last = search_start;
- }
again:
- while(1) {
- ret = find_first_extent_bit(block_group_cache, last,
- &start, &end, bit);
- if (ret)
+ while (1) {
+ cache = btrfs_lookup_first_block_group(root->fs_info, last);
+ if (!cache)
break;
- ret = get_state_private(block_group_cache, start, &ptr);
- if (ret) {
- last = end + 1;
- continue;
- }
-
- cache = (struct btrfs_block_group_cache *)(unsigned long)ptr;
spin_lock(&cache->lock);
last = cache->key.objectid + cache->key.offset;
used = btrfs_block_group_used(&cache->item);
- if (!cache->ro && block_group_bits(cache, data)) {
- free_check = div_factor(cache->key.offset, factor);
- if (used + cache->pinned < free_check) {
- found_group = cache;
+ if ((full_search || !cache->ro) &&
+ block_group_bits(cache, BTRFS_BLOCK_GROUP_METADATA)) {
+ if (used + cache->pinned + cache->reserved <
+ div_factor(cache->key.offset, factor)) {
+ group_start = cache->key.objectid;
spin_unlock(&cache->lock);
+ put_block_group(cache);
goto found;
}
}
spin_unlock(&cache->lock);
+ put_block_group(cache);
cond_resched();
}
if (!wrapped) {
goto again;
}
found:
- return found_group;
-}
-
-struct btrfs_block_group_cache *btrfs_find_block_group(struct btrfs_root *root,
- struct btrfs_block_group_cache
- *hint, u64 search_start,
- int data, int owner)
-{
-
- struct btrfs_block_group_cache *ret;
- ret = __btrfs_find_block_group(root, hint, search_start, data, owner);
- return ret;
-}
-static u64 hash_extent_ref(u64 root_objectid, u64 ref_generation,
- u64 owner, u64 owner_offset)
-{
- u32 high_crc = ~(u32)0;
- u32 low_crc = ~(u32)0;
- __le64 lenum;
- lenum = cpu_to_le64(root_objectid);
- high_crc = btrfs_crc32c(high_crc, &lenum, sizeof(lenum));
- lenum = cpu_to_le64(ref_generation);
- low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum));
- if (owner >= BTRFS_FIRST_FREE_OBJECTID) {
- lenum = cpu_to_le64(owner);
- low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum));
- lenum = cpu_to_le64(owner_offset);
- low_crc = btrfs_crc32c(low_crc, &lenum, sizeof(lenum));
- }
- return ((u64)high_crc << 32) | (u64)low_crc;
+ return group_start;
}
-static int match_extent_ref(struct extent_buffer *leaf,
- struct btrfs_extent_ref *disk_ref,
- struct btrfs_extent_ref *cpu_ref)
+/* simple helper to search for an existing extent at a given offset */
+int btrfs_lookup_extent(struct btrfs_root *root, u64 start, u64 len)
{
int ret;
- int len;
-
- if (cpu_ref->objectid)
- len = sizeof(*cpu_ref);
- else
- len = 2 * sizeof(u64);
- ret = memcmp_extent_buffer(leaf, cpu_ref, (unsigned long)disk_ref,
- len);
- return ret == 0;
-}
-
-static int noinline lookup_extent_backref(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- struct btrfs_path *path, u64 bytenr,
- u64 root_objectid,
- u64 ref_generation, u64 owner,
- u64 owner_offset, int del)
-{
- u64 hash;
struct btrfs_key key;
- struct btrfs_key found_key;
- struct btrfs_extent_ref ref;
- struct extent_buffer *leaf;
- struct btrfs_extent_ref *disk_ref;
- int ret;
- int ret2;
-
- btrfs_set_stack_ref_root(&ref, root_objectid);
- btrfs_set_stack_ref_generation(&ref, ref_generation);
- btrfs_set_stack_ref_objectid(&ref, owner);
- btrfs_set_stack_ref_offset(&ref, owner_offset);
-
- hash = hash_extent_ref(root_objectid, ref_generation, owner,
- owner_offset);
- key.offset = hash;
- key.objectid = bytenr;
- key.type = BTRFS_EXTENT_REF_KEY;
+ struct btrfs_path *path;
- while (1) {
- ret = btrfs_search_slot(trans, root, &key, path,
- del ? -1 : 0, del);
- if (ret < 0)
- goto out;
- leaf = path->nodes[0];
- if (ret != 0) {
- u32 nritems = btrfs_header_nritems(leaf);
- if (path->slots[0] >= nritems) {
- ret2 = btrfs_next_leaf(root, path);
- if (ret2)
- goto out;
- leaf = path->nodes[0];
- }
- btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
- if (found_key.objectid != bytenr ||
- found_key.type != BTRFS_EXTENT_REF_KEY)
- goto out;
- key.offset = found_key.offset;
- if (del) {
- btrfs_release_path(root, path);
- continue;
- }
- }
- disk_ref = btrfs_item_ptr(path->nodes[0],
- path->slots[0],
- struct btrfs_extent_ref);
- if (match_extent_ref(path->nodes[0], disk_ref, &ref)) {
- ret = 0;
- goto out;
- }
- btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
- key.offset = found_key.offset + 1;
- btrfs_release_path(root, path);
- }
-out:
+ path = btrfs_alloc_path();
+ BUG_ON(!path);
+ key.objectid = start;
+ key.offset = len;
+ btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
+ ret = btrfs_search_slot(NULL, root->fs_info->extent_root, &key, path,
+ 0, 0);
+ btrfs_free_path(path);
return ret;
}
* File extents can be referenced by:
*
* - multiple snapshots, subvolumes, or different generations in one subvol
- * - different files inside a single subvolume (in theory, not implemented yet)
+ * - different files inside a single subvolume
* - different offsets inside a file (bookend extents in file.c)
*
* The extent ref structure has fields for:
* - Objectid of the subvolume root
* - Generation number of the tree holding the reference
* - objectid of the file holding the reference
- * - offset in the file corresponding to the key holding the reference
+ * - number of references holding by parent node (alway 1 for tree blocks)
+ *
+ * Btree leaf may hold multiple references to a file extent. In most cases,
+ * these references are from same file and the corresponding offsets inside
+ * the file are close together.
*
* When a file extent is allocated the fields are filled in:
- * (root_key.objectid, trans->transid, inode objectid, offset in file)
+ * (root_key.objectid, trans->transid, inode objectid, 1)
*
* When a leaf is cow'd new references are added for every file extent found
- * in the leaf. It looks the same as the create case, but trans->transid
- * will be different when the block is cow'd.
+ * in the leaf. It looks similar to the create case, but trans->transid will
+ * be different when the block is cow'd.
*
- * (root_key.objectid, trans->transid, inode objectid, offset in file)
+ * (root_key.objectid, trans->transid, inode objectid,
+ * number of references in the leaf)
*
- * When a file extent is removed either during snapshot deletion or file
- * truncation, the corresponding back reference is found
- * by searching for:
+ * When a file extent is removed either during snapshot deletion or
+ * file truncation, we find the corresponding back reference and check
+ * the following fields:
*
* (btrfs_header_owner(leaf), btrfs_header_generation(leaf),
- * inode objectid, offset in file)
+ * inode objectid)
*
* Btree extents can be referenced by:
*
* - Different subvolumes
* - Different generations of the same subvolume
*
- * Storing sufficient information for a full reverse mapping of a btree
- * block would require storing the lowest key of the block in the backref,
- * and it would require updating that lowest key either before write out or
- * every time it changed. Instead, the objectid of the lowest key is stored
- * along with the level of the tree block. This provides a hint
- * about where in the btree the block can be found. Searches through the
- * btree only need to look for a pointer to that block, so they stop one
- * level higher than the level recorded in the backref.
- *
- * Some btrees do not do reference counting on their extents. These
- * include the extent tree and the tree of tree roots. Backrefs for these
- * trees always have a generation of zero.
- *
* When a tree block is created, back references are inserted:
*
- * (root->root_key.objectid, trans->transid or zero, level, lowest_key_objectid)
+ * (root->root_key.objectid, trans->transid, level, 1)
*
- * When a tree block is cow'd in a reference counted root,
- * new back references are added for all the blocks it points to.
- * These are of the form (trans->transid will have increased since creation):
+ * When a tree block is cow'd, new back references are added for all the
+ * blocks it points to. If the tree block isn't in reference counted root,
+ * the old back references are removed. These new back references are of
+ * the form (trans->transid will have increased since creation):
*
- * (root->root_key.objectid, trans->transid, level, lowest_key_objectid)
+ * (root->root_key.objectid, trans->transid, level, 1)
*
- * Because the lowest_key_objectid and the level are just hints
- * they are not used when backrefs are deleted. When a backref is deleted:
+ * When a backref is in deleting, the following fields are checked:
*
* if backref was for a tree root:
- * root_objectid = root->root_key.objectid
+ * (btrfs_header_owner(itself), btrfs_header_generation(itself), level)
* else
- * root_objectid = btrfs_header_owner(parent)
- *
- * (root_objectid, btrfs_header_generation(parent) or zero, 0, 0)
+ * (btrfs_header_owner(parent), btrfs_header_generation(parent), level)
*
- * Back Reference Key hashing:
+ * Back Reference Key composing:
*
- * Back references have four fields, each 64 bits long. Unfortunately,
- * This is hashed into a single 64 bit number and placed into the key offset.
- * The key objectid corresponds to the first byte in the extent, and the
- * key type is set to BTRFS_EXTENT_REF_KEY
+ * The key objectid corresponds to the first byte in the extent, the key
+ * type is set to BTRFS_EXTENT_REF_KEY, and the key offset is the first
+ * byte of parent extent. If a extent is tree root, the key offset is set
+ * to the key objectid.
*/
-int btrfs_insert_extent_backref(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- struct btrfs_path *path, u64 bytenr,
- u64 root_objectid, u64 ref_generation,
- u64 owner, u64 owner_offset)
+
+static noinline int lookup_extent_backref(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path,
+ u64 bytenr, u64 parent,
+ u64 ref_root, u64 ref_generation,
+ u64 owner_objectid, int del)
{
- u64 hash;
struct btrfs_key key;
- struct btrfs_extent_ref ref;
- struct btrfs_extent_ref *disk_ref;
+ struct btrfs_extent_ref *ref;
+ struct extent_buffer *leaf;
+ u64 ref_objectid;
int ret;
- btrfs_set_stack_ref_root(&ref, root_objectid);
- btrfs_set_stack_ref_generation(&ref, ref_generation);
- btrfs_set_stack_ref_objectid(&ref, owner);
- btrfs_set_stack_ref_offset(&ref, owner_offset);
-
- hash = hash_extent_ref(root_objectid, ref_generation, owner,
- owner_offset);
- key.offset = hash;
key.objectid = bytenr;
key.type = BTRFS_EXTENT_REF_KEY;
+ key.offset = parent;
- ret = btrfs_insert_empty_item(trans, root, path, &key, sizeof(ref));
- while (ret == -EEXIST) {
- disk_ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
- struct btrfs_extent_ref);
- if (match_extent_ref(path->nodes[0], disk_ref, &ref))
- goto out;
- key.offset++;
- btrfs_release_path(root, path);
- ret = btrfs_insert_empty_item(trans, root, path, &key,
- sizeof(ref));
+ ret = btrfs_search_slot(trans, root, &key, path, del ? -1 : 0, 1);
+ if (ret < 0)
+ goto out;
+ if (ret > 0) {
+ ret = -ENOENT;
+ goto out;
}
- if (ret)
+
+ leaf = path->nodes[0];
+ ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_ref);
+ ref_objectid = btrfs_ref_objectid(leaf, ref);
+ if (btrfs_ref_root(leaf, ref) != ref_root ||
+ btrfs_ref_generation(leaf, ref) != ref_generation ||
+ (ref_objectid != owner_objectid &&
+ ref_objectid != BTRFS_MULTIPLE_OBJECTIDS)) {
+ ret = -EIO;
+ WARN_ON(1);
goto out;
- disk_ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
- struct btrfs_extent_ref);
- write_extent_buffer(path->nodes[0], &ref, (unsigned long)disk_ref,
- sizeof(ref));
- btrfs_mark_buffer_dirty(path->nodes[0]);
+ }
+ ret = 0;
out:
- btrfs_release_path(root, path);
return ret;
}
-static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- u64 bytenr, u64 num_bytes,
- u64 root_objectid, u64 ref_generation,
- u64 owner, u64 owner_offset)
+/*
+ * updates all the backrefs that are pending on update_list for the
+ * extent_root
+ */
+static noinline int update_backrefs(struct btrfs_trans_handle *trans,
+ struct btrfs_root *extent_root,
+ struct btrfs_path *path,
+ struct list_head *update_list)
{
- struct btrfs_path *path;
- int ret;
struct btrfs_key key;
- struct extent_buffer *l;
- struct btrfs_extent_item *item;
- u32 refs;
-
- WARN_ON(num_bytes < root->sectorsize);
- path = btrfs_alloc_path();
- if (!path)
- return -ENOMEM;
+ struct btrfs_extent_ref *ref;
+ struct btrfs_fs_info *info = extent_root->fs_info;
+ struct pending_extent_op *op;
+ struct extent_buffer *leaf;
+ int ret = 0;
+ struct list_head *cur = update_list->next;
+ u64 ref_objectid;
+ u64 ref_root = extent_root->root_key.objectid;
- path->reada = 1;
- key.objectid = bytenr;
- btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
- key.offset = num_bytes;
- ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path,
- 0, 1);
- if (ret < 0)
- return ret;
- if (ret != 0) {
- BUG();
- }
- BUG_ON(ret != 0);
- l = path->nodes[0];
- item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item);
- refs = btrfs_extent_refs(l, item);
- btrfs_set_extent_refs(l, item, refs + 1);
- btrfs_mark_buffer_dirty(path->nodes[0]);
+ op = list_entry(cur, struct pending_extent_op, list);
- btrfs_release_path(root->fs_info->extent_root, path);
+search:
+ key.objectid = op->bytenr;
+ key.type = BTRFS_EXTENT_REF_KEY;
+ key.offset = op->orig_parent;
- path->reada = 1;
- ret = btrfs_insert_extent_backref(trans, root->fs_info->extent_root,
- path, bytenr, root_objectid,
- ref_generation, owner, owner_offset);
+ ret = btrfs_search_slot(trans, extent_root, &key, path, 0, 1);
BUG_ON(ret);
- finish_current_insert(trans, root->fs_info->extent_root);
- del_pending_extents(trans, root->fs_info->extent_root);
- btrfs_free_path(path);
- return 0;
-}
+ leaf = path->nodes[0];
-int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- u64 bytenr, u64 num_bytes,
- u64 root_objectid, u64 ref_generation,
- u64 owner, u64 owner_offset)
-{
- int ret;
+loop:
+ ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_ref);
+
+ ref_objectid = btrfs_ref_objectid(leaf, ref);
+
+ if (btrfs_ref_root(leaf, ref) != ref_root ||
+ btrfs_ref_generation(leaf, ref) != op->orig_generation ||
+ (ref_objectid != op->level &&
+ ref_objectid != BTRFS_MULTIPLE_OBJECTIDS)) {
+ printk(KERN_ERR "btrfs couldn't find %llu, parent %llu, "
+ "root %llu, owner %u\n",
+ (unsigned long long)op->bytenr,
+ (unsigned long long)op->orig_parent,
+ (unsigned long long)ref_root, op->level);
+ btrfs_print_leaf(extent_root, leaf);
+ BUG();
+ }
- mutex_lock(&root->fs_info->alloc_mutex);
- ret = __btrfs_inc_extent_ref(trans, root, bytenr, num_bytes,
- root_objectid, ref_generation,
- owner, owner_offset);
- mutex_unlock(&root->fs_info->alloc_mutex);
- return ret;
-}
+ key.objectid = op->bytenr;
+ key.offset = op->parent;
+ key.type = BTRFS_EXTENT_REF_KEY;
+ ret = btrfs_set_item_key_safe(trans, extent_root, path, &key);
+ BUG_ON(ret);
+ ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_ref);
+ btrfs_set_ref_generation(leaf, ref, op->generation);
-int btrfs_extent_post_op(struct btrfs_trans_handle *trans,
- struct btrfs_root *root)
-{
- finish_current_insert(trans, root->fs_info->extent_root);
- del_pending_extents(trans, root->fs_info->extent_root);
- return 0;
-}
+ cur = cur->next;
-static int lookup_extent_ref(struct btrfs_trans_handle *trans,
- struct btrfs_root *root, u64 bytenr,
- u64 num_bytes, u32 *refs)
-{
- struct btrfs_path *path;
- int ret;
- struct btrfs_key key;
- struct extent_buffer *l;
- struct btrfs_extent_item *item;
+ list_del_init(&op->list);
+ unlock_extent(&info->extent_ins, op->bytenr,
+ op->bytenr + op->num_bytes - 1, GFP_NOFS);
+ kfree(op);
- WARN_ON(num_bytes < root->sectorsize);
- path = btrfs_alloc_path();
- path->reada = 1;
- key.objectid = bytenr;
- key.offset = num_bytes;
- btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
- ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path,
- 0, 0);
- if (ret < 0)
+ if (cur == update_list) {
+ btrfs_mark_buffer_dirty(path->nodes[0]);
+ btrfs_release_path(extent_root, path);
goto out;
- if (ret != 0) {
- btrfs_print_leaf(root, path->nodes[0]);
- printk("failed to find block number %Lu\n", bytenr);
- BUG();
}
- l = path->nodes[0];
- item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item);
- *refs = btrfs_extent_refs(l, item);
+
+ op = list_entry(cur, struct pending_extent_op, list);
+
+ path->slots[0]++;
+ while (path->slots[0] < btrfs_header_nritems(leaf)) {
+ btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
+ if (key.objectid == op->bytenr &&
+ key.type == BTRFS_EXTENT_REF_KEY)
+ goto loop;
+ path->slots[0]++;
+ }
+
+ btrfs_mark_buffer_dirty(path->nodes[0]);
+ btrfs_release_path(extent_root, path);
+ goto search;
+
out:
- btrfs_free_path(path);
return 0;
}
-
-static int get_reference_status(struct btrfs_root *root, u64 bytenr,
- u64 parent_gen, u64 ref_objectid,
- u64 *min_generation, u32 *ref_count)
+static noinline int insert_extents(struct btrfs_trans_handle *trans,
+ struct btrfs_root *extent_root,
+ struct btrfs_path *path,
+ struct list_head *insert_list, int nr)
{
- struct btrfs_root *extent_root = root->fs_info->extent_root;
- struct btrfs_path *path;
+ struct btrfs_key *keys;
+ u32 *data_size;
+ struct pending_extent_op *op;
struct extent_buffer *leaf;
- struct btrfs_extent_ref *ref_item;
- struct btrfs_key key;
- struct btrfs_key found_key;
- u64 root_objectid = root->root_key.objectid;
- u64 ref_generation;
- u32 nritems;
- int ret;
+ struct list_head *cur = insert_list->next;
+ struct btrfs_fs_info *info = extent_root->fs_info;
+ u64 ref_root = extent_root->root_key.objectid;
+ int i = 0, last = 0, ret;
+ int total = nr * 2;
- key.objectid = bytenr;
- key.offset = 0;
- key.type = BTRFS_EXTENT_ITEM_KEY;
+ if (!nr)
+ return 0;
- path = btrfs_alloc_path();
- mutex_lock(&root->fs_info->alloc_mutex);
- ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
- if (ret < 0)
- goto out;
- BUG_ON(ret == 0);
+ keys = kzalloc(total * sizeof(struct btrfs_key), GFP_NOFS);
+ if (!keys)
+ return -ENOMEM;
- leaf = path->nodes[0];
- btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
+ data_size = kzalloc(total * sizeof(u32), GFP_NOFS);
+ if (!data_size) {
+ kfree(keys);
+ return -ENOMEM;
+ }
- if (found_key.objectid != bytenr ||
- found_key.type != BTRFS_EXTENT_ITEM_KEY) {
- ret = 1;
- goto out;
+ list_for_each_entry(op, insert_list, list) {
+ keys[i].objectid = op->bytenr;
+ keys[i].offset = op->num_bytes;
+ keys[i].type = BTRFS_EXTENT_ITEM_KEY;
+ data_size[i] = sizeof(struct btrfs_extent_item);
+ i++;
+
+ keys[i].objectid = op->bytenr;
+ keys[i].offset = op->parent;
+ keys[i].type = BTRFS_EXTENT_REF_KEY;
+ data_size[i] = sizeof(struct btrfs_extent_ref);
+ i++;
}
- *ref_count = 0;
- *min_generation = (u64)-1;
+ op = list_entry(cur, struct pending_extent_op, list);
+ i = 0;
+ while (i < total) {
+ int c;
+ ret = btrfs_insert_some_items(trans, extent_root, path,
+ keys+i, data_size+i, total-i);
+ BUG_ON(ret < 0);
+
+ if (last && ret > 1)
+ BUG();
- while (1) {
leaf = path->nodes[0];
- nritems = btrfs_header_nritems(leaf);
- if (path->slots[0] >= nritems) {
- ret = btrfs_next_leaf(extent_root, path);
- if (ret < 0)
- goto out;
- if (ret == 0)
- continue;
- break;
- }
- btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
- if (found_key.objectid != bytenr)
- break;
+ for (c = 0; c < ret; c++) {
+ int ref_first = keys[i].type == BTRFS_EXTENT_REF_KEY;
+
+ /*
+ * if the first item we inserted was a backref, then
+ * the EXTENT_ITEM will be the odd c's, else it will
+ * be the even c's
+ */
+ if ((ref_first && (c % 2)) ||
+ (!ref_first && !(c % 2))) {
+ struct btrfs_extent_item *itm;
+
+ itm = btrfs_item_ptr(leaf, path->slots[0] + c,
+ struct btrfs_extent_item);
+ btrfs_set_extent_refs(path->nodes[0], itm, 1);
+ op->del++;
+ } else {
+ struct btrfs_extent_ref *ref;
+
+ ref = btrfs_item_ptr(leaf, path->slots[0] + c,
+ struct btrfs_extent_ref);
+ btrfs_set_ref_root(leaf, ref, ref_root);
+ btrfs_set_ref_generation(leaf, ref,
+ op->generation);
+ btrfs_set_ref_objectid(leaf, ref, op->level);
+ btrfs_set_ref_num_refs(leaf, ref, 1);
+ op->del++;
+ }
- if (found_key.type != BTRFS_EXTENT_REF_KEY) {
- path->slots[0]++;
- continue;
+ /*
+ * using del to see when its ok to free up the
+ * pending_extent_op. In the case where we insert the
+ * last item on the list in order to help do batching
+ * we need to not free the extent op until we actually
+ * insert the extent_item
+ */
+ if (op->del == 2) {
+ unlock_extent(&info->extent_ins, op->bytenr,
+ op->bytenr + op->num_bytes - 1,
+ GFP_NOFS);
+ cur = cur->next;
+ list_del_init(&op->list);
+ kfree(op);
+ if (cur != insert_list)
+ op = list_entry(cur,
+ struct pending_extent_op,
+ list);
+ }
}
+ btrfs_mark_buffer_dirty(leaf);
+ btrfs_release_path(extent_root, path);
- ref_item = btrfs_item_ptr(leaf, path->slots[0],
- struct btrfs_extent_ref);
- ref_generation = btrfs_ref_generation(leaf, ref_item);
/*
- * For (parent_gen > 0 && parent_gen > ref_gen):
- *
- * we reach here through the oldest root, therefore
- * all other reference from same snapshot should have
- * a larger generation.
+ * Ok backref's and items usually go right next to eachother,
+ * but if we could only insert 1 item that means that we
+ * inserted on the end of a leaf, and we have no idea what may
+ * be on the next leaf so we just play it safe. In order to
+ * try and help this case we insert the last thing on our
+ * insert list so hopefully it will end up being the last
+ * thing on the leaf and everything else will be before it,
+ * which will let us insert a whole bunch of items at the same
+ * time.
*/
- if ((root_objectid != btrfs_ref_root(leaf, ref_item)) ||
- (parent_gen > 0 && parent_gen > ref_generation) ||
- (ref_objectid >= BTRFS_FIRST_FREE_OBJECTID &&
- ref_objectid != btrfs_ref_objectid(leaf, ref_item))) {
- if (ref_count)
- *ref_count = 2;
- break;
+ if (ret == 1 && !last && (i + ret < total)) {
+ /*
+ * last: where we will pick up the next time around
+ * i: our current key to insert, will be total - 1
+ * cur: the current op we are screwing with
+ * op: duh
+ */
+ last = i + ret;
+ i = total - 1;
+ cur = insert_list->prev;
+ op = list_entry(cur, struct pending_extent_op, list);
+ } else if (last) {
+ /*
+ * ok we successfully inserted the last item on the
+ * list, lets reset everything
+ *
+ * i: our current key to insert, so where we left off
+ * last time
+ * last: done with this
+ * cur: the op we are messing with
+ * op: duh
+ * total: since we inserted the last key, we need to
+ * decrement total so we dont overflow
+ */
+ i = last;
+ last = 0;
+ total--;
+ if (i < total) {
+ cur = insert_list->next;
+ op = list_entry(cur, struct pending_extent_op,
+ list);
+ }
+ } else {
+ i += ret;
}
- *ref_count = 1;
- if (*min_generation > ref_generation)
- *min_generation = ref_generation;
-
- path->slots[0]++;
+ cond_resched();
}
ret = 0;
-out:
- mutex_unlock(&root->fs_info->alloc_mutex);
- btrfs_free_path(path);
+ kfree(keys);
+ kfree(data_size);
return ret;
}
-int btrfs_cross_ref_exists(struct btrfs_root *root,
- struct btrfs_key *key, u64 bytenr)
+static noinline int insert_extent_backref(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path,
+ u64 bytenr, u64 parent,
+ u64 ref_root, u64 ref_generation,
+ u64 owner_objectid)
{
- struct btrfs_trans_handle *trans;
- struct btrfs_root *old_root;
- struct btrfs_path *path = NULL;
- struct extent_buffer *eb;
- struct btrfs_file_extent_item *item;
- u64 ref_generation;
- u64 min_generation;
- u64 extent_start;
- u32 ref_count;
- int level;
+ struct btrfs_key key;
+ struct extent_buffer *leaf;
+ struct btrfs_extent_ref *ref;
+ u32 num_refs;
int ret;
- BUG_ON(key->type != BTRFS_EXTENT_DATA_KEY);
- ret = get_reference_status(root, bytenr, 0, key->objectid,
- &min_generation, &ref_count);
- if (ret)
- return ret;
+ key.objectid = bytenr;
+ key.type = BTRFS_EXTENT_REF_KEY;
+ key.offset = parent;
- if (ref_count != 1)
- return 1;
+ ret = btrfs_insert_empty_item(trans, root, path, &key, sizeof(*ref));
+ if (ret == 0) {
+ leaf = path->nodes[0];
+ ref = btrfs_item_ptr(leaf, path->slots[0],
+ struct btrfs_extent_ref);
+ btrfs_set_ref_root(leaf, ref, ref_root);
+ btrfs_set_ref_generation(leaf, ref, ref_generation);
+ btrfs_set_ref_objectid(leaf, ref, owner_objectid);
+ btrfs_set_ref_num_refs(leaf, ref, 1);
+ } else if (ret == -EEXIST) {
+ u64 existing_owner;
+ BUG_ON(owner_objectid < BTRFS_FIRST_FREE_OBJECTID);
+ leaf = path->nodes[0];
+ ref = btrfs_item_ptr(leaf, path->slots[0],
+ struct btrfs_extent_ref);
+ if (btrfs_ref_root(leaf, ref) != ref_root ||
+ btrfs_ref_generation(leaf, ref) != ref_generation) {
+ ret = -EIO;
+ WARN_ON(1);
+ goto out;
+ }
- trans = btrfs_start_transaction(root, 0);
- old_root = root->dirty_root->root;
- ref_generation = old_root->root_key.offset;
+ num_refs = btrfs_ref_num_refs(leaf, ref);
+ BUG_ON(num_refs == 0);
+ btrfs_set_ref_num_refs(leaf, ref, num_refs + 1);
- /* all references are created in running transaction */
- if (min_generation > ref_generation) {
+ existing_owner = btrfs_ref_objectid(leaf, ref);
+ if (existing_owner != owner_objectid &&
+ existing_owner != BTRFS_MULTIPLE_OBJECTIDS) {
+ btrfs_set_ref_objectid(leaf, ref,
+ BTRFS_MULTIPLE_OBJECTIDS);
+ }
ret = 0;
+ } else {
goto out;
}
+ btrfs_mark_buffer_dirty(path->nodes[0]);
+out:
+ btrfs_release_path(root, path);
+ return ret;
+}
- path = btrfs_alloc_path();
- if (!path) {
- ret = -ENOMEM;
- goto out;
- }
-
- path->skip_locking = 1;
- /* if no item found, the extent is referenced by other snapshot */
- ret = btrfs_search_slot(NULL, old_root, key, path, 0, 0);
- if (ret)
- goto out;
+static noinline int remove_extent_backref(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path)
+{
+ struct extent_buffer *leaf;
+ struct btrfs_extent_ref *ref;
+ u32 num_refs;
+ int ret = 0;
- eb = path->nodes[0];
- item = btrfs_item_ptr(eb, path->slots[0],
- struct btrfs_file_extent_item);
- if (btrfs_file_extent_type(eb, item) != BTRFS_FILE_EXTENT_REG ||
- btrfs_file_extent_disk_bytenr(eb, item) != bytenr) {
- ret = 1;
- goto out;
+ leaf = path->nodes[0];
+ ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_ref);
+ num_refs = btrfs_ref_num_refs(leaf, ref);
+ BUG_ON(num_refs == 0);
+ num_refs -= 1;
+ if (num_refs == 0) {
+ ret = btrfs_del_item(trans, root, path);
+ } else {
+ btrfs_set_ref_num_refs(leaf, ref, num_refs);
+ btrfs_mark_buffer_dirty(leaf);
}
+ btrfs_release_path(root, path);
+ return ret;
+}
- for (level = BTRFS_MAX_LEVEL - 1; level >= -1; level--) {
- if (level >= 0) {
- eb = path->nodes[level];
- if (!eb)
- continue;
- extent_start = eb->start;
- } else
- extent_start = bytenr;
-
- ret = get_reference_status(root, extent_start, ref_generation,
- 0, &min_generation, &ref_count);
- if (ret)
- goto out;
+#ifdef BIO_RW_DISCARD
+static void btrfs_issue_discard(struct block_device *bdev,
+ u64 start, u64 len)
+{
+ blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_KERNEL);
+}
+#endif
- if (ref_count != 1) {
- ret = 1;
- goto out;
+static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
+ u64 num_bytes)
+{
+#ifdef BIO_RW_DISCARD
+ int ret;
+ u64 map_length = num_bytes;
+ struct btrfs_multi_bio *multi = NULL;
+
+ /* Tell the block device(s) that the sectors can be discarded */
+ ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
+ bytenr, &map_length, &multi, 0);
+ if (!ret) {
+ struct btrfs_bio_stripe *stripe = multi->stripes;
+ int i;
+
+ if (map_length > num_bytes)
+ map_length = num_bytes;
+
+ for (i = 0; i < multi->num_stripes; i++, stripe++) {
+ btrfs_issue_discard(stripe->dev->bdev,
+ stripe->physical,
+ map_length);
}
- if (level >= 0)
- ref_generation = btrfs_header_generation(eb);
+ kfree(multi);
}
- ret = 0;
-out:
- if (path)
- btrfs_free_path(path);
- btrfs_end_transaction(trans, root);
+
return ret;
+#else
+ return 0;
+#endif
}
-int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
- struct extent_buffer *buf, int cache_ref)
+static noinline int free_extents(struct btrfs_trans_handle *trans,
+ struct btrfs_root *extent_root,
+ struct list_head *del_list)
{
- u64 bytenr;
- u32 nritems;
- struct btrfs_key key;
- struct btrfs_file_extent_item *fi;
- int i;
- int level;
- int ret;
- int faili;
- int nr_file_extents = 0;
+ struct btrfs_fs_info *info = extent_root->fs_info;
+ struct btrfs_path *path;
+ struct btrfs_key key, found_key;
+ struct extent_buffer *leaf;
+ struct list_head *cur;
+ struct pending_extent_op *op;
+ struct btrfs_extent_item *ei;
+ int ret, num_to_del, extent_slot = 0, found_extent = 0;
+ u32 refs;
+ u64 bytes_freed = 0;
- if (!root->ref_cows)
- return 0;
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+ path->reada = 1;
- level = btrfs_header_level(buf);
- nritems = btrfs_header_nritems(buf);
- for (i = 0; i < nritems; i++) {
- cond_resched();
- if (level == 0) {
- u64 disk_bytenr;
- btrfs_item_key_to_cpu(buf, &key, i);
- if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
- continue;
- fi = btrfs_item_ptr(buf, i,
- struct btrfs_file_extent_item);
- if (btrfs_file_extent_type(buf, fi) ==
- BTRFS_FILE_EXTENT_INLINE)
- continue;
- disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
- if (disk_bytenr == 0)
- continue;
+search:
+ /* search for the backref for the current ref we want to delete */
+ cur = del_list->next;
+ op = list_entry(cur, struct pending_extent_op, list);
+ ret = lookup_extent_backref(trans, extent_root, path, op->bytenr,
+ op->orig_parent,
+ extent_root->root_key.objectid,
+ op->orig_generation, op->level, 1);
+ if (ret) {
+ printk(KERN_ERR "btrfs unable to find backref byte nr %llu "
+ "root %llu gen %llu owner %u\n",
+ (unsigned long long)op->bytenr,
+ (unsigned long long)extent_root->root_key.objectid,
+ (unsigned long long)op->orig_generation, op->level);
+ btrfs_print_leaf(extent_root, path->nodes[0]);
+ WARN_ON(1);
+ goto out;
+ }
- if (buf != root->commit_root)
- nr_file_extents++;
+ extent_slot = path->slots[0];
+ num_to_del = 1;
+ found_extent = 0;
- mutex_lock(&root->fs_info->alloc_mutex);
- ret = __btrfs_inc_extent_ref(trans, root, disk_bytenr,
- btrfs_file_extent_disk_num_bytes(buf, fi),
- root->root_key.objectid, trans->transid,
- key.objectid, key.offset);
- mutex_unlock(&root->fs_info->alloc_mutex);
- if (ret) {
- faili = i;
- WARN_ON(1);
- goto fail;
- }
- } else {
- bytenr = btrfs_node_blockptr(buf, i);
- btrfs_node_key_to_cpu(buf, &key, i);
-
- mutex_lock(&root->fs_info->alloc_mutex);
- ret = __btrfs_inc_extent_ref(trans, root, bytenr,
- btrfs_level_size(root, level - 1),
- root->root_key.objectid,
- trans->transid,
- level - 1, key.objectid);
- mutex_unlock(&root->fs_info->alloc_mutex);
- if (ret) {
- faili = i;
- WARN_ON(1);
- goto fail;
- }
+ /*
+ * if we aren't the first item on the leaf we can move back one and see
+ * if our ref is right next to our extent item
+ */
+ if (likely(extent_slot)) {
+ extent_slot--;
+ btrfs_item_key_to_cpu(path->nodes[0], &found_key,
+ extent_slot);
+ if (found_key.objectid == op->bytenr &&
+ found_key.type == BTRFS_EXTENT_ITEM_KEY &&
+ found_key.offset == op->num_bytes) {
+ num_to_del++;
+ found_extent = 1;
}
}
- /* cache orignal leaf block's references */
- if (level == 0 && cache_ref && buf != root->commit_root) {
- struct btrfs_leaf_ref *ref;
- struct btrfs_extent_info *info;
- ref = btrfs_alloc_leaf_ref(nr_file_extents);
- if (!ref) {
- WARN_ON(1);
- goto out;
+ /*
+ * if we didn't find the extent we need to delete the backref and then
+ * search for the extent item key so we can update its ref count
+ */
+ if (!found_extent) {
+ key.objectid = op->bytenr;
+ key.type = BTRFS_EXTENT_ITEM_KEY;
+ key.offset = op->num_bytes;
+
+ ret = remove_extent_backref(trans, extent_root, path);
+ BUG_ON(ret);
+ btrfs_release_path(extent_root, path);
+ ret = btrfs_search_slot(trans, extent_root, &key, path, -1, 1);
+ BUG_ON(ret);
+ extent_slot = path->slots[0];
+ }
+
+ /* this is where we update the ref count for the extent */
+ leaf = path->nodes[0];
+ ei = btrfs_item_ptr(leaf, extent_slot, struct btrfs_extent_item);
+ refs = btrfs_extent_refs(leaf, ei);
+ BUG_ON(refs == 0);
+ refs--;
+ btrfs_set_extent_refs(leaf, ei, refs);
+
+ btrfs_mark_buffer_dirty(leaf);
+
+ /*
+ * This extent needs deleting. The reason cur_slot is extent_slot +
+ * num_to_del is because extent_slot points to the slot where the extent
+ * is, and if the backref was not right next to the extent we will be
+ * deleting at least 1 item, and will want to start searching at the
+ * slot directly next to extent_slot. However if we did find the
+ * backref next to the extent item them we will be deleting at least 2
+ * items and will want to start searching directly after the ref slot
+ */
+ if (!refs) {
+ struct list_head *pos, *n, *end;
+ int cur_slot = extent_slot+num_to_del;
+ u64 super_used;
+ u64 root_used;
+
+ path->slots[0] = extent_slot;
+ bytes_freed = op->num_bytes;
+
+ mutex_lock(&info->pinned_mutex);
+ ret = pin_down_bytes(trans, extent_root, op->bytenr,
+ op->num_bytes, op->level >=
+ BTRFS_FIRST_FREE_OBJECTID);
+ mutex_unlock(&info->pinned_mutex);
+ BUG_ON(ret < 0);
+ op->del = ret;
+
+ /*
+ * we need to see if we can delete multiple things at once, so
+ * start looping through the list of extents we are wanting to
+ * delete and see if their extent/backref's are right next to
+ * eachother and the extents only have 1 ref
+ */
+ for (pos = cur->next; pos != del_list; pos = pos->next) {
+ struct pending_extent_op *tmp;
+
+ tmp = list_entry(pos, struct pending_extent_op, list);
+
+ /* we only want to delete extent+ref at this stage */
+ if (cur_slot >= btrfs_header_nritems(leaf) - 1)
+ break;
+
+ btrfs_item_key_to_cpu(leaf, &found_key, cur_slot);
+ if (found_key.objectid != tmp->bytenr ||
+ found_key.type != BTRFS_EXTENT_ITEM_KEY ||
+ found_key.offset != tmp->num_bytes)
+ break;
+
+ /* check to make sure this extent only has one ref */
+ ei = btrfs_item_ptr(leaf, cur_slot,
+ struct btrfs_extent_item);
+ if (btrfs_extent_refs(leaf, ei) != 1)
+ break;
+
+ btrfs_item_key_to_cpu(leaf, &found_key, cur_slot+1);
+ if (found_key.objectid != tmp->bytenr ||
+ found_key.type != BTRFS_EXTENT_REF_KEY ||
+ found_key.offset != tmp->orig_parent)
+ break;
+
+ /*
+ * the ref is right next to the extent, we can set the
+ * ref count to 0 since we will delete them both now
+ */
+ btrfs_set_extent_refs(leaf, ei, 0);
+
+ /* pin down the bytes for this extent */
+ mutex_lock(&info->pinned_mutex);
+ ret = pin_down_bytes(trans, extent_root, tmp->bytenr,
+ tmp->num_bytes, tmp->level >=
+ BTRFS_FIRST_FREE_OBJECTID);
+ mutex_unlock(&info->pinned_mutex);
+ BUG_ON(ret < 0);
+
+ /*
+ * use the del field to tell if we need to go ahead and
+ * free up the extent when we delete the item or not.
+ */
+ tmp->del = ret;
+ bytes_freed += tmp->num_bytes;
+
+ num_to_del += 2;
+ cur_slot += 2;
}
+ end = pos;
- ref->bytenr = buf->start;
- ref->owner = btrfs_header_owner(buf);
- ref->generation = btrfs_header_generation(buf);
- ref->nritems = nr_file_extents;
- info = ref->extents;
-
- for (i = 0; nr_file_extents > 0 && i < nritems; i++) {
- u64 disk_bytenr;
- btrfs_item_key_to_cpu(buf, &key, i);
- if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
- continue;
- fi = btrfs_item_ptr(buf, i,
- struct btrfs_file_extent_item);
- if (btrfs_file_extent_type(buf, fi) ==
- BTRFS_FILE_EXTENT_INLINE)
- continue;
- disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
- if (disk_bytenr == 0)
- continue;
+ /* update the free space counters */
+ spin_lock(&info->delalloc_lock);
+ super_used = btrfs_super_bytes_used(&info->super_copy);
+ btrfs_set_super_bytes_used(&info->super_copy,
+ super_used - bytes_freed);
- info->bytenr = disk_bytenr;
- info->num_bytes =
- btrfs_file_extent_disk_num_bytes(buf, fi);
- info->objectid = key.objectid;
- info->offset = key.offset;
- info++;
+ root_used = btrfs_root_used(&extent_root->root_item);
+ btrfs_set_root_used(&extent_root->root_item,
+ root_used - bytes_freed);
+ spin_unlock(&info->delalloc_lock);
+
+ /* delete the items */
+ ret = btrfs_del_items(trans, extent_root, path,
+ path->slots[0], num_to_del);
+ BUG_ON(ret);
+
+ /*
+ * loop through the extents we deleted and do the cleanup work
+ * on them
+ */
+ for (pos = cur, n = pos->next; pos != end;
+ pos = n, n = pos->next) {
+ struct pending_extent_op *tmp;
+ tmp = list_entry(pos, struct pending_extent_op, list);
+
+ /*
+ * remember tmp->del tells us wether or not we pinned
+ * down the extent
+ */
+ ret = update_block_group(trans, extent_root,
+ tmp->bytenr, tmp->num_bytes, 0,
+ tmp->del);
+ BUG_ON(ret);
+
+ list_del_init(&tmp->list);
+ unlock_extent(&info->extent_ins, tmp->bytenr,
+ tmp->bytenr + tmp->num_bytes - 1,
+ GFP_NOFS);
+ kfree(tmp);
}
+ } else if (refs && found_extent) {
+ /*
+ * the ref and extent were right next to eachother, but the
+ * extent still has a ref, so just free the backref and keep
+ * going
+ */
+ ret = remove_extent_backref(trans, extent_root, path);
+ BUG_ON(ret);
- BUG_ON(!root->ref_tree);
- ret = btrfs_add_leaf_ref(root, ref);
- WARN_ON(ret);
- btrfs_free_leaf_ref(ref);
+ list_del_init(&op->list);
+ unlock_extent(&info->extent_ins, op->bytenr,
+ op->bytenr + op->num_bytes - 1, GFP_NOFS);
+ kfree(op);
+ } else {
+ /*
+ * the extent has multiple refs and the backref we were looking
+ * for was not right next to it, so just unlock and go next,
+ * we're good to go
+ */
+ list_del_init(&op->list);
+ unlock_extent(&info->extent_ins, op->bytenr,
+ op->bytenr + op->num_bytes - 1, GFP_NOFS);
+ kfree(op);
}
+
+ btrfs_release_path(extent_root, path);
+ if (!list_empty(del_list))
+ goto search;
+
out:
- return 0;
-fail:
- WARN_ON(1);
-#if 0
- for (i =0; i < faili; i++) {
- if (level == 0) {
- u64 disk_bytenr;
- btrfs_item_key_to_cpu(buf, &key, i);
- if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
- continue;
- fi = btrfs_item_ptr(buf, i,
- struct btrfs_file_extent_item);
- if (btrfs_file_extent_type(buf, fi) ==
- BTRFS_FILE_EXTENT_INLINE)
- continue;
- disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
- if (disk_bytenr == 0)
- continue;
- err = btrfs_free_extent(trans, root, disk_bytenr,
- btrfs_file_extent_disk_num_bytes(buf,
- fi), 0);
- BUG_ON(err);
- } else {
- bytenr = btrfs_node_blockptr(buf, i);
- err = btrfs_free_extent(trans, root, bytenr,
- btrfs_level_size(root, level - 1), 0);
- BUG_ON(err);
- }
- }
-#endif
+ btrfs_free_path(path);
return ret;
}
-static int write_one_cache_group(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- struct btrfs_path *path,
- struct btrfs_block_group_cache *cache)
+static int __btrfs_update_extent_ref(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, u64 bytenr,
+ u64 orig_parent, u64 parent,
+ u64 orig_root, u64 ref_root,
+ u64 orig_generation, u64 ref_generation,
+ u64 owner_objectid)
{
int ret;
- int pending_ret;
struct btrfs_root *extent_root = root->fs_info->extent_root;
- unsigned long bi;
- struct extent_buffer *leaf;
+ struct btrfs_path *path;
- ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
- if (ret < 0)
- goto fail;
- BUG_ON(ret);
+ if (root == root->fs_info->extent_root) {
+ struct pending_extent_op *extent_op;
+ u64 num_bytes;
+
+ BUG_ON(owner_objectid >= BTRFS_MAX_LEVEL);
+ num_bytes = btrfs_level_size(root, (int)owner_objectid);
+ mutex_lock(&root->fs_info->extent_ins_mutex);
+ if (test_range_bit(&root->fs_info->extent_ins, bytenr,
+ bytenr + num_bytes - 1, EXTENT_WRITEBACK, 0)) {
+ u64 priv;
+ ret = get_state_private(&root->fs_info->extent_ins,
+ bytenr, &priv);
+ BUG_ON(ret);
+ extent_op = (struct pending_extent_op *)
+ (unsigned long)priv;
+ BUG_ON(extent_op->parent != orig_parent);
+ BUG_ON(extent_op->generation != orig_generation);
- leaf = path->nodes[0];
- bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
- write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item));
- btrfs_mark_buffer_dirty(leaf);
- btrfs_release_path(extent_root, path);
-fail:
- finish_current_insert(trans, extent_root);
- pending_ret = del_pending_extents(trans, extent_root);
- if (ret)
- return ret;
- if (pending_ret)
- return pending_ret;
- return 0;
+ extent_op->parent = parent;
+ extent_op->generation = ref_generation;
+ } else {
+ extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
+ BUG_ON(!extent_op);
+
+ extent_op->type = PENDING_BACKREF_UPDATE;
+ extent_op->bytenr = bytenr;
+ extent_op->num_bytes = num_bytes;
+ extent_op->parent = parent;
+ extent_op->orig_parent = orig_parent;
+ extent_op->generation = ref_generation;
+ extent_op->orig_generation = orig_generation;
+ extent_op->level = (int)owner_objectid;
+ INIT_LIST_HEAD(&extent_op->list);
+ extent_op->del = 0;
+
+ set_extent_bits(&root->fs_info->extent_ins,
+ bytenr, bytenr + num_bytes - 1,
+ EXTENT_WRITEBACK, GFP_NOFS);
+ set_state_private(&root->fs_info->extent_ins,
+ bytenr, (unsigned long)extent_op);
+ }
+ mutex_unlock(&root->fs_info->extent_ins_mutex);
+ return 0;
+ }
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+ ret = lookup_extent_backref(trans, extent_root, path,
+ bytenr, orig_parent, orig_root,
+ orig_generation, owner_objectid, 1);
+ if (ret)
+ goto out;
+ ret = remove_extent_backref(trans, extent_root, path);
+ if (ret)
+ goto out;
+ ret = insert_extent_backref(trans, extent_root, path, bytenr,
+ parent, ref_root, ref_generation,
+ owner_objectid);
+ BUG_ON(ret);
+ finish_current_insert(trans, extent_root, 0);
+ del_pending_extents(trans, extent_root, 0);
+out:
+ btrfs_free_path(path);
+ return ret;
}
-int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
- struct btrfs_root *root)
+int btrfs_update_extent_ref(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, u64 bytenr,
+ u64 orig_parent, u64 parent,
+ u64 ref_root, u64 ref_generation,
+ u64 owner_objectid)
{
- struct extent_io_tree *block_group_cache;
- struct btrfs_block_group_cache *cache;
int ret;
- int err = 0;
- int werr = 0;
+ if (ref_root == BTRFS_TREE_LOG_OBJECTID &&
+ owner_objectid < BTRFS_FIRST_FREE_OBJECTID)
+ return 0;
+ ret = __btrfs_update_extent_ref(trans, root, bytenr, orig_parent,
+ parent, ref_root, ref_root,
+ ref_generation, ref_generation,
+ owner_objectid);
+ return ret;
+}
+
+static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, u64 bytenr,
+ u64 orig_parent, u64 parent,
+ u64 orig_root, u64 ref_root,
+ u64 orig_generation, u64 ref_generation,
+ u64 owner_objectid)
+{
struct btrfs_path *path;
- u64 last = 0;
- u64 start;
- u64 end;
- u64 ptr;
+ int ret;
+ struct btrfs_key key;
+ struct extent_buffer *l;
+ struct btrfs_extent_item *item;
+ u32 refs;
- block_group_cache = &root->fs_info->block_group_cache;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
- mutex_lock(&root->fs_info->alloc_mutex);
- while(1) {
- ret = find_first_extent_bit(block_group_cache, last,
- &start, &end, BLOCK_GROUP_DIRTY);
- if (ret)
- break;
+ path->reada = 1;
+ key.objectid = bytenr;
+ key.type = BTRFS_EXTENT_ITEM_KEY;
+ key.offset = (u64)-1;
- last = end + 1;
- ret = get_state_private(block_group_cache, start, &ptr);
- if (ret)
- break;
- cache = (struct btrfs_block_group_cache *)(unsigned long)ptr;
- err = write_one_cache_group(trans, root,
- path, cache);
- /*
- * if we fail to write the cache group, we want
- * to keep it marked dirty in hopes that a later
- * write will work
- */
- if (err) {
- werr = err;
- continue;
- }
- clear_extent_bits(block_group_cache, start, end,
- BLOCK_GROUP_DIRTY, GFP_NOFS);
+ ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path,
+ 0, 1);
+ if (ret < 0)
+ return ret;
+ BUG_ON(ret == 0 || path->slots[0] == 0);
+
+ path->slots[0]--;
+ l = path->nodes[0];
+
+ btrfs_item_key_to_cpu(l, &key, path->slots[0]);
+ if (key.objectid != bytenr) {
+ btrfs_print_leaf(root->fs_info->extent_root, path->nodes[0]);
+ printk(KERN_ERR "btrfs wanted %llu found %llu\n",
+ (unsigned long long)bytenr,
+ (unsigned long long)key.objectid);
+ BUG();
}
+ BUG_ON(key.type != BTRFS_EXTENT_ITEM_KEY);
+
+ item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item);
+ refs = btrfs_extent_refs(l, item);
+ btrfs_set_extent_refs(l, item, refs + 1);
+ btrfs_mark_buffer_dirty(path->nodes[0]);
+
+ btrfs_release_path(root->fs_info->extent_root, path);
+
+ path->reada = 1;
+ ret = insert_extent_backref(trans, root->fs_info->extent_root,
+ path, bytenr, parent,
+ ref_root, ref_generation,
+ owner_objectid);
+ BUG_ON(ret);
+ finish_current_insert(trans, root->fs_info->extent_root, 0);
+ del_pending_extents(trans, root->fs_info->extent_root, 0);
+
btrfs_free_path(path);
- mutex_unlock(&root->fs_info->alloc_mutex);
- return werr;
+ return 0;
}
-static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
- u64 flags)
+int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ u64 bytenr, u64 num_bytes, u64 parent,
+ u64 ref_root, u64 ref_generation,
+ u64 owner_objectid)
{
- struct list_head *head = &info->space_info;
- struct list_head *cur;
- struct btrfs_space_info *found;
- list_for_each(cur, head) {
- found = list_entry(cur, struct btrfs_space_info, list);
- if (found->flags == flags)
- return found;
- }
- return NULL;
-
+ int ret;
+ if (ref_root == BTRFS_TREE_LOG_OBJECTID &&
+ owner_objectid < BTRFS_FIRST_FREE_OBJECTID)
+ return 0;
+ ret = __btrfs_inc_extent_ref(trans, root, bytenr, 0, parent,
+ 0, ref_root, 0, ref_generation,
+ owner_objectid);
+ return ret;
}
-static int update_space_info(struct btrfs_fs_info *info, u64 flags,
- u64 total_bytes, u64 bytes_used,
- struct btrfs_space_info **space_info)
+int btrfs_extent_post_op(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root)
{
- struct btrfs_space_info *found;
+ u64 start;
+ u64 end;
+ int ret;
- found = __find_space_info(info, flags);
- if (found) {
- found->total_bytes += total_bytes;
- found->bytes_used += bytes_used;
- found->full = 0;
- WARN_ON(found->total_bytes < found->bytes_used);
- *space_info = found;
+ while(1) {
+ finish_current_insert(trans, root->fs_info->extent_root, 1);
+ del_pending_extents(trans, root->fs_info->extent_root, 1);
+
+ /* is there more work to do? */
+ ret = find_first_extent_bit(&root->fs_info->pending_del,
+ 0, &start, &end, EXTENT_WRITEBACK);
+ if (!ret)
+ continue;
+ ret = find_first_extent_bit(&root->fs_info->extent_ins,
+ 0, &start, &end, EXTENT_WRITEBACK);
+ if (!ret)
+ continue;
+ break;
+ }
+ return 0;
+}
+
+int btrfs_lookup_extent_ref(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, u64 bytenr,
+ u64 num_bytes, u32 *refs)
+{
+ struct btrfs_path *path;
+ int ret;
+ struct btrfs_key key;
+ struct extent_buffer *l;
+ struct btrfs_extent_item *item;
+
+ WARN_ON(num_bytes < root->sectorsize);
+ path = btrfs_alloc_path();
+ path->reada = 1;
+ key.objectid = bytenr;
+ key.offset = num_bytes;
+ btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
+ ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path,
+ 0, 0);
+ if (ret < 0)
+ goto out;
+ if (ret != 0) {
+ btrfs_print_leaf(root, path->nodes[0]);
+ printk(KERN_INFO "btrfs failed to find block number %llu\n",
+ (unsigned long long)bytenr);
+ BUG();
+ }
+ l = path->nodes[0];
+ item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item);
+ *refs = btrfs_extent_refs(l, item);
+out:
+ btrfs_free_path(path);
+ return 0;
+}
+
+int btrfs_cross_ref_exist(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, u64 objectid, u64 bytenr)
+{
+ struct btrfs_root *extent_root = root->fs_info->extent_root;
+ struct btrfs_path *path;
+ struct extent_buffer *leaf;
+ struct btrfs_extent_ref *ref_item;
+ struct btrfs_key key;
+ struct btrfs_key found_key;
+ u64 ref_root;
+ u64 last_snapshot;
+ u32 nritems;
+ int ret;
+
+ key.objectid = bytenr;
+ key.offset = (u64)-1;
+ key.type = BTRFS_EXTENT_ITEM_KEY;
+
+ path = btrfs_alloc_path();
+ ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
+ if (ret < 0)
+ goto out;
+ BUG_ON(ret == 0);
+
+ ret = -ENOENT;
+ if (path->slots[0] == 0)
+ goto out;
+
+ path->slots[0]--;
+ leaf = path->nodes[0];
+ btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
+
+ if (found_key.objectid != bytenr ||
+ found_key.type != BTRFS_EXTENT_ITEM_KEY)
+ goto out;
+
+ last_snapshot = btrfs_root_last_snapshot(&root->root_item);
+ while (1) {
+ leaf = path->nodes[0];
+ nritems = btrfs_header_nritems(leaf);
+ if (path->slots[0] >= nritems) {
+ ret = btrfs_next_leaf(extent_root, path);
+ if (ret < 0)
+ goto out;
+ if (ret == 0)
+ continue;
+ break;
+ }
+ btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
+ if (found_key.objectid != bytenr)
+ break;
+
+ if (found_key.type != BTRFS_EXTENT_REF_KEY) {
+ path->slots[0]++;
+ continue;
+ }
+
+ ref_item = btrfs_item_ptr(leaf, path->slots[0],
+ struct btrfs_extent_ref);
+ ref_root = btrfs_ref_root(leaf, ref_item);
+ if ((ref_root != root->root_key.objectid &&
+ ref_root != BTRFS_TREE_LOG_OBJECTID) ||
+ objectid != btrfs_ref_objectid(leaf, ref_item)) {
+ ret = 1;
+ goto out;
+ }
+ if (btrfs_ref_generation(leaf, ref_item) <= last_snapshot) {
+ ret = 1;
+ goto out;
+ }
+
+ path->slots[0]++;
+ }
+ ret = 0;
+out:
+ btrfs_free_path(path);
+ return ret;
+}
+
+int btrfs_cache_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
+ struct extent_buffer *buf, u32 nr_extents)
+{
+ struct btrfs_key key;
+ struct btrfs_file_extent_item *fi;
+ u64 root_gen;
+ u32 nritems;
+ int i;
+ int level;
+ int ret = 0;
+ int shared = 0;
+
+ if (!root->ref_cows)
return 0;
+
+ if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
+ shared = 0;
+ root_gen = root->root_key.offset;
+ } else {
+ shared = 1;
+ root_gen = trans->transid - 1;
}
- found = kmalloc(sizeof(*found), GFP_NOFS);
- if (!found)
- return -ENOMEM;
- list_add(&found->list, &info->space_info);
- found->flags = flags;
- found->total_bytes = total_bytes;
- found->bytes_used = bytes_used;
- found->bytes_pinned = 0;
- found->full = 0;
- found->force_alloc = 0;
- *space_info = found;
- return 0;
+ level = btrfs_header_level(buf);
+ nritems = btrfs_header_nritems(buf);
+
+ if (level == 0) {
+ struct btrfs_leaf_ref *ref;
+ struct btrfs_extent_info *info;
+
+ ref = btrfs_alloc_leaf_ref(root, nr_extents);
+ if (!ref) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ ref->root_gen = root_gen;
+ ref->bytenr = buf->start;
+ ref->owner = btrfs_header_owner(buf);
+ ref->generation = btrfs_header_generation(buf);
+ ref->nritems = nr_extents;
+ info = ref->extents;
+
+ for (i = 0; nr_extents > 0 && i < nritems; i++) {
+ u64 disk_bytenr;
+ btrfs_item_key_to_cpu(buf, &key, i);
+ if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
+ continue;
+ fi = btrfs_item_ptr(buf, i,
+ struct btrfs_file_extent_item);
+ if (btrfs_file_extent_type(buf, fi) ==
+ BTRFS_FILE_EXTENT_INLINE)
+ continue;
+ disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
+ if (disk_bytenr == 0)
+ continue;
+
+ info->bytenr = disk_bytenr;
+ info->num_bytes =
+ btrfs_file_extent_disk_num_bytes(buf, fi);
+ info->objectid = key.objectid;
+ info->offset = key.offset;
+ info++;
+ }
+
+ ret = btrfs_add_leaf_ref(root, ref, shared);
+ if (ret == -EEXIST && shared) {
+ struct btrfs_leaf_ref *old;
+ old = btrfs_lookup_leaf_ref(root, ref->bytenr);
+ BUG_ON(!old);
+ btrfs_remove_leaf_ref(root, old);
+ btrfs_free_leaf_ref(root, old);
+ ret = btrfs_add_leaf_ref(root, ref, shared);
+ }
+ WARN_ON(ret);
+ btrfs_free_leaf_ref(root, ref);
+ }
+out:
+ return ret;
+}
+
+/* when a block goes through cow, we update the reference counts of
+ * everything that block points to. The internal pointers of the block
+ * can be in just about any order, and it is likely to have clusters of
+ * things that are close together and clusters of things that are not.
+ *
+ * To help reduce the seeks that come with updating all of these reference
+ * counts, sort them by byte number before actual updates are done.
+ *
+ * struct refsort is used to match byte number to slot in the btree block.
+ * we sort based on the byte number and then use the slot to actually
+ * find the item.
+ *
+ * struct refsort is smaller than strcut btrfs_item and smaller than
+ * struct btrfs_key_ptr. Since we're currently limited to the page size
+ * for a btree block, there's no way for a kmalloc of refsorts for a
+ * single node to be bigger than a page.
+ */
+struct refsort {
+ u64 bytenr;
+ u32 slot;
+};
+
+/*
+ * for passing into sort()
+ */
+static int refsort_cmp(const void *a_void, const void *b_void)
+{
+ const struct refsort *a = a_void;
+ const struct refsort *b = b_void;
+
+ if (a->bytenr < b->bytenr)
+ return -1;
+ if (a->bytenr > b->bytenr)
+ return 1;
+ return 0;
+}
+
+
+noinline int btrfs_inc_ref(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct extent_buffer *orig_buf,
+ struct extent_buffer *buf, u32 *nr_extents)
+{
+ u64 bytenr;
+ u64 ref_root;
+ u64 orig_root;
+ u64 ref_generation;
+ u64 orig_generation;
+ struct refsort *sorted;
+ u32 nritems;
+ u32 nr_file_extents = 0;
+ struct btrfs_key key;
+ struct btrfs_file_extent_item *fi;
+ int i;
+ int level;
+ int ret = 0;
+ int faili = 0;
+ int refi = 0;
+ int slot;
+ int (*process_func)(struct btrfs_trans_handle *, struct btrfs_root *,
+ u64, u64, u64, u64, u64, u64, u64, u64);
+
+ ref_root = btrfs_header_owner(buf);
+ ref_generation = btrfs_header_generation(buf);
+ orig_root = btrfs_header_owner(orig_buf);
+ orig_generation = btrfs_header_generation(orig_buf);
+
+ nritems = btrfs_header_nritems(buf);
+ level = btrfs_header_level(buf);
+
+ sorted = kmalloc(sizeof(struct refsort) * nritems, GFP_NOFS);
+ BUG_ON(!sorted);
+
+ if (root->ref_cows) {
+ process_func = __btrfs_inc_extent_ref;
+ } else {
+ if (level == 0 &&
+ root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID)
+ goto out;
+ if (level != 0 &&
+ root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID)
+ goto out;
+ process_func = __btrfs_update_extent_ref;
+ }
+
+ /*
+ * we make two passes through the items. In the first pass we
+ * only record the byte number and slot. Then we sort based on
+ * byte number and do the actual work based on the sorted results
+ */
+ for (i = 0; i < nritems; i++) {
+ cond_resched();
+ if (level == 0) {
+ btrfs_item_key_to_cpu(buf, &key, i);
+ if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
+ continue;
+ fi = btrfs_item_ptr(buf, i,
+ struct btrfs_file_extent_item);
+ if (btrfs_file_extent_type(buf, fi) ==
+ BTRFS_FILE_EXTENT_INLINE)
+ continue;
+ bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
+ if (bytenr == 0)
+ continue;
+
+ nr_file_extents++;
+ sorted[refi].bytenr = bytenr;
+ sorted[refi].slot = i;
+ refi++;
+ } else {
+ bytenr = btrfs_node_blockptr(buf, i);
+ sorted[refi].bytenr = bytenr;
+ sorted[refi].slot = i;
+ refi++;
+ }
+ }
+ /*
+ * if refi == 0, we didn't actually put anything into the sorted
+ * array and we're done
+ */
+ if (refi == 0)
+ goto out;
+
+ sort(sorted, refi, sizeof(struct refsort), refsort_cmp, NULL);
+
+ for (i = 0; i < refi; i++) {
+ cond_resched();
+ slot = sorted[i].slot;
+ bytenr = sorted[i].bytenr;
+
+ if (level == 0) {
+ btrfs_item_key_to_cpu(buf, &key, slot);
+
+ ret = process_func(trans, root, bytenr,
+ orig_buf->start, buf->start,
+ orig_root, ref_root,
+ orig_generation, ref_generation,
+ key.objectid);
+
+ if (ret) {
+ faili = slot;
+ WARN_ON(1);
+ goto fail;
+ }
+ } else {
+ ret = process_func(trans, root, bytenr,
+ orig_buf->start, buf->start,
+ orig_root, ref_root,
+ orig_generation, ref_generation,
+ level - 1);
+ if (ret) {
+ faili = slot;
+ WARN_ON(1);
+ goto fail;
+ }
+ }
+ }
+out:
+ kfree(sorted);
+ if (nr_extents) {
+ if (level == 0)
+ *nr_extents = nr_file_extents;
+ else
+ *nr_extents = nritems;
+ }
+ return 0;
+fail:
+ kfree(sorted);
+ WARN_ON(1);
+ return ret;
+}
+
+int btrfs_update_ref(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, struct extent_buffer *orig_buf,
+ struct extent_buffer *buf, int start_slot, int nr)
+
+{
+ u64 bytenr;
+ u64 ref_root;
+ u64 orig_root;
+ u64 ref_generation;
+ u64 orig_generation;
+ struct btrfs_key key;
+ struct btrfs_file_extent_item *fi;
+ int i;
+ int ret;
+ int slot;
+ int level;
+
+ BUG_ON(start_slot < 0);
+ BUG_ON(start_slot + nr > btrfs_header_nritems(buf));
+
+ ref_root = btrfs_header_owner(buf);
+ ref_generation = btrfs_header_generation(buf);
+ orig_root = btrfs_header_owner(orig_buf);
+ orig_generation = btrfs_header_generation(orig_buf);
+ level = btrfs_header_level(buf);
+
+ if (!root->ref_cows) {
+ if (level == 0 &&
+ root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID)
+ return 0;
+ if (level != 0 &&
+ root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID)
+ return 0;
+ }
+
+ for (i = 0, slot = start_slot; i < nr; i++, slot++) {
+ cond_resched();
+ if (level == 0) {
+ btrfs_item_key_to_cpu(buf, &key, slot);
+ if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
+ continue;
+ fi = btrfs_item_ptr(buf, slot,
+ struct btrfs_file_extent_item);
+ if (btrfs_file_extent_type(buf, fi) ==
+ BTRFS_FILE_EXTENT_INLINE)
+ continue;
+ bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
+ if (bytenr == 0)
+ continue;
+ ret = __btrfs_update_extent_ref(trans, root, bytenr,
+ orig_buf->start, buf->start,
+ orig_root, ref_root,
+ orig_generation, ref_generation,
+ key.objectid);
+ if (ret)
+ goto fail;
+ } else {
+ bytenr = btrfs_node_blockptr(buf, slot);
+ ret = __btrfs_update_extent_ref(trans, root, bytenr,
+ orig_buf->start, buf->start,
+ orig_root, ref_root,
+ orig_generation, ref_generation,
+ level - 1);
+ if (ret)
+ goto fail;
+ }
+ }
+ return 0;
+fail:
+ WARN_ON(1);
+ return -1;
+}
+
+static int write_one_cache_group(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path,
+ struct btrfs_block_group_cache *cache)
+{
+ int ret;
+ int pending_ret;
+ struct btrfs_root *extent_root = root->fs_info->extent_root;
+ unsigned long bi;
+ struct extent_buffer *leaf;
+
+ ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
+ if (ret < 0)
+ goto fail;
+ BUG_ON(ret);
+
+ leaf = path->nodes[0];
+ bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
+ write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item));
+ btrfs_mark_buffer_dirty(leaf);
+ btrfs_release_path(extent_root, path);
+fail:
+ finish_current_insert(trans, extent_root, 0);
+ pending_ret = del_pending_extents(trans, extent_root, 0);
+ if (ret)
+ return ret;
+ if (pending_ret)
+ return pending_ret;
+ return 0;
+
+}
+
+int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root)
+{
+ struct btrfs_block_group_cache *cache, *entry;
+ struct rb_node *n;
+ int err = 0;
+ int werr = 0;
+ struct btrfs_path *path;
+ u64 last = 0;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ while (1) {
+ cache = NULL;
+ spin_lock(&root->fs_info->block_group_cache_lock);
+ for (n = rb_first(&root->fs_info->block_group_cache_tree);
+ n; n = rb_next(n)) {
+ entry = rb_entry(n, struct btrfs_block_group_cache,
+ cache_node);
+ if (entry->dirty) {
+ cache = entry;
+ break;
+ }
+ }
+ spin_unlock(&root->fs_info->block_group_cache_lock);
+
+ if (!cache)
+ break;
+
+ cache->dirty = 0;
+ last += cache->key.offset;
+
+ err = write_one_cache_group(trans, root,
+ path, cache);
+ /*
+ * if we fail to write the cache group, we want
+ * to keep it marked dirty in hopes that a later
+ * write will work
+ */
+ if (err) {
+ werr = err;
+ continue;
+ }
+ }
+ btrfs_free_path(path);
+ return werr;
+}
+
+int btrfs_extent_readonly(struct btrfs_root *root, u64 bytenr)
+{
+ struct btrfs_block_group_cache *block_group;
+ int readonly = 0;
+
+ block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
+ if (!block_group || block_group->ro)
+ readonly = 1;
+ if (block_group)
+ put_block_group(block_group);
+ return readonly;
+}
+
+static int update_space_info(struct btrfs_fs_info *info, u64 flags,
+ u64 total_bytes, u64 bytes_used,
+ struct btrfs_space_info **space_info)
+{
+ struct btrfs_space_info *found;
+
+ found = __find_space_info(info, flags);
+ if (found) {
+ spin_lock(&found->lock);
+ found->total_bytes += total_bytes;
+ found->bytes_used += bytes_used;
+ found->full = 0;
+ spin_unlock(&found->lock);
+ *space_info = found;
+ return 0;
+ }
+ found = kzalloc(sizeof(*found), GFP_NOFS);
+ if (!found)
+ return -ENOMEM;
+
+ list_add(&found->list, &info->space_info);
+ INIT_LIST_HEAD(&found->block_groups);
+ init_rwsem(&found->groups_sem);
+ spin_lock_init(&found->lock);
+ found->flags = flags;
+ found->total_bytes = total_bytes;
+ found->bytes_used = bytes_used;
+ found->bytes_pinned = 0;
+ found->bytes_reserved = 0;
+ found->bytes_readonly = 0;
+ found->bytes_delalloc = 0;
+ found->full = 0;
+ found->force_alloc = 0;
+ *space_info = found;
+ return 0;
+}
+
+static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
+{
+ u64 extra_flags = flags & (BTRFS_BLOCK_GROUP_RAID0 |
+ BTRFS_BLOCK_GROUP_RAID1 |
+ BTRFS_BLOCK_GROUP_RAID10 |
+ BTRFS_BLOCK_GROUP_DUP);
+ if (extra_flags) {
+ if (flags & BTRFS_BLOCK_GROUP_DATA)
+ fs_info->avail_data_alloc_bits |= extra_flags;
+ if (flags & BTRFS_BLOCK_GROUP_METADATA)
+ fs_info->avail_metadata_alloc_bits |= extra_flags;
+ if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
+ fs_info->avail_system_alloc_bits |= extra_flags;
+ }
+}
+
+static void set_block_group_readonly(struct btrfs_block_group_cache *cache)
+{
+ spin_lock(&cache->space_info->lock);
+ spin_lock(&cache->lock);
+ if (!cache->ro) {
+ cache->space_info->bytes_readonly += cache->key.offset -
+ btrfs_block_group_used(&cache->item);
+ cache->ro = 1;
+ }
+ spin_unlock(&cache->lock);
+ spin_unlock(&cache->space_info->lock);
+}
+
+u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags)
+{
+ u64 num_devices = root->fs_info->fs_devices->rw_devices;
+
+ if (num_devices == 1)
+ flags &= ~(BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID0);
+ if (num_devices < 4)
+ flags &= ~BTRFS_BLOCK_GROUP_RAID10;
+
+ if ((flags & BTRFS_BLOCK_GROUP_DUP) &&
+ (flags & (BTRFS_BLOCK_GROUP_RAID1 |
+ BTRFS_BLOCK_GROUP_RAID10))) {
+ flags &= ~BTRFS_BLOCK_GROUP_DUP;
+ }
+
+ if ((flags & BTRFS_BLOCK_GROUP_RAID1) &&
+ (flags & BTRFS_BLOCK_GROUP_RAID10)) {
+ flags &= ~BTRFS_BLOCK_GROUP_RAID1;
+ }
+
+ if ((flags & BTRFS_BLOCK_GROUP_RAID0) &&
+ ((flags & BTRFS_BLOCK_GROUP_RAID1) |
+ (flags & BTRFS_BLOCK_GROUP_RAID10) |
+ (flags & BTRFS_BLOCK_GROUP_DUP)))
+ flags &= ~BTRFS_BLOCK_GROUP_RAID0;
+ return flags;
+}
+
+static u64 btrfs_get_alloc_profile(struct btrfs_root *root, u64 data)
+{
+ struct btrfs_fs_info *info = root->fs_info;
+ u64 alloc_profile;
+
+ if (data) {
+ alloc_profile = info->avail_data_alloc_bits &
+ info->data_alloc_profile;
+ data = BTRFS_BLOCK_GROUP_DATA | alloc_profile;
+ } else if (root == root->fs_info->chunk_root) {
+ alloc_profile = info->avail_system_alloc_bits &
+ info->system_alloc_profile;
+ data = BTRFS_BLOCK_GROUP_SYSTEM | alloc_profile;
+ } else {
+ alloc_profile = info->avail_metadata_alloc_bits &
+ info->metadata_alloc_profile;
+ data = BTRFS_BLOCK_GROUP_METADATA | alloc_profile;
+ }
+
+ return btrfs_reduce_alloc_profile(root, data);
+}
+
+void btrfs_set_inode_space_info(struct btrfs_root *root, struct inode *inode)
+{
+ u64 alloc_target;
+
+ alloc_target = btrfs_get_alloc_profile(root, 1);
+ BTRFS_I(inode)->space_info = __find_space_info(root->fs_info,
+ alloc_target);
+}
+
+/*
+ * for now this just makes sure we have at least 5% of our metadata space free
+ * for use.
+ */
+int btrfs_check_metadata_free_space(struct btrfs_root *root)
+{
+ struct btrfs_fs_info *info = root->fs_info;
+ struct btrfs_space_info *meta_sinfo;
+ u64 alloc_target, thresh;
+ int committed = 0, ret;
+
+ /* get the space info for where the metadata will live */
+ alloc_target = btrfs_get_alloc_profile(root, 0);
+ meta_sinfo = __find_space_info(info, alloc_target);
+
+again:
+ spin_lock(&meta_sinfo->lock);
+ if (!meta_sinfo->full)
+ thresh = meta_sinfo->total_bytes * 80;
+ else
+ thresh = meta_sinfo->total_bytes * 95;
+
+ do_div(thresh, 100);
+
+ if (meta_sinfo->bytes_used + meta_sinfo->bytes_reserved +
+ meta_sinfo->bytes_pinned + meta_sinfo->bytes_readonly > thresh) {
+ struct btrfs_trans_handle *trans;
+ if (!meta_sinfo->full) {
+ meta_sinfo->force_alloc = 1;
+ spin_unlock(&meta_sinfo->lock);
+
+ trans = btrfs_start_transaction(root, 1);
+ if (!trans)
+ return -ENOMEM;
+
+ ret = do_chunk_alloc(trans, root->fs_info->extent_root,
+ 2 * 1024 * 1024, alloc_target, 0);
+ btrfs_end_transaction(trans, root);
+ goto again;
+ }
+ spin_unlock(&meta_sinfo->lock);
+
+ if (!committed) {
+ committed = 1;
+ trans = btrfs_join_transaction(root, 1);
+ if (!trans)
+ return -ENOMEM;
+ ret = btrfs_commit_transaction(trans, root);
+ if (ret)
+ return ret;
+ goto again;
+ }
+ return -ENOSPC;
+ }
+ spin_unlock(&meta_sinfo->lock);
+
+ return 0;
+}
+
+/*
+ * This will check the space that the inode allocates from to make sure we have
+ * enough space for bytes.
+ */
+int btrfs_check_data_free_space(struct btrfs_root *root, struct inode *inode,
+ u64 bytes)
+{
+ struct btrfs_space_info *data_sinfo;
+ int ret = 0, committed = 0;
+
+ /* make sure bytes are sectorsize aligned */
+ bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
+
+ data_sinfo = BTRFS_I(inode)->space_info;
+again:
+ /* make sure we have enough space to handle the data first */
+ spin_lock(&data_sinfo->lock);
+ if (data_sinfo->total_bytes - data_sinfo->bytes_used -
+ data_sinfo->bytes_delalloc - data_sinfo->bytes_reserved -
+ data_sinfo->bytes_pinned - data_sinfo->bytes_readonly -
+ data_sinfo->bytes_may_use < bytes) {
+ struct btrfs_trans_handle *trans;
+
+ /*
+ * if we don't have enough free bytes in this space then we need
+ * to alloc a new chunk.
+ */
+ if (!data_sinfo->full) {
+ u64 alloc_target;
+
+ data_sinfo->force_alloc = 1;
+ spin_unlock(&data_sinfo->lock);
+
+ alloc_target = btrfs_get_alloc_profile(root, 1);
+ trans = btrfs_start_transaction(root, 1);
+ if (!trans)
+ return -ENOMEM;
+
+ ret = do_chunk_alloc(trans, root->fs_info->extent_root,
+ bytes + 2 * 1024 * 1024,
+ alloc_target, 0);
+ btrfs_end_transaction(trans, root);
+ if (ret)
+ return ret;
+ goto again;
+ }
+ spin_unlock(&data_sinfo->lock);
+
+ /* commit the current transaction and try again */
+ if (!committed) {
+ committed = 1;
+ trans = btrfs_join_transaction(root, 1);
+ if (!trans)
+ return -ENOMEM;
+ ret = btrfs_commit_transaction(trans, root);
+ if (ret)
+ return ret;
+ goto again;
+ }
+
+ printk(KERN_ERR "no space left, need %llu, %llu delalloc bytes"
+ ", %llu bytes_used, %llu bytes_reserved, "
+ "%llu bytes_pinned, %llu bytes_readonly, %llu may use"
+ "%llu total\n", bytes, data_sinfo->bytes_delalloc,
+ data_sinfo->bytes_used, data_sinfo->bytes_reserved,
+ data_sinfo->bytes_pinned, data_sinfo->bytes_readonly,
+ data_sinfo->bytes_may_use, data_sinfo->total_bytes);
+ return -ENOSPC;
+ }
+ data_sinfo->bytes_may_use += bytes;
+ BTRFS_I(inode)->reserved_bytes += bytes;
+ spin_unlock(&data_sinfo->lock);
+
+ return btrfs_check_metadata_free_space(root);
+}
+
+/*
+ * if there was an error for whatever reason after calling
+ * btrfs_check_data_free_space, call this so we can cleanup the counters.
+ */
+void btrfs_free_reserved_data_space(struct btrfs_root *root,
+ struct inode *inode, u64 bytes)
+{
+ struct btrfs_space_info *data_sinfo;
+
+ /* make sure bytes are sectorsize aligned */
+ bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
+
+ data_sinfo = BTRFS_I(inode)->space_info;
+ spin_lock(&data_sinfo->lock);
+ data_sinfo->bytes_may_use -= bytes;
+ BTRFS_I(inode)->reserved_bytes -= bytes;
+ spin_unlock(&data_sinfo->lock);
+}
+
+/* called when we are adding a delalloc extent to the inode's io_tree */
+void btrfs_delalloc_reserve_space(struct btrfs_root *root, struct inode *inode,
+ u64 bytes)
+{
+ struct btrfs_space_info *data_sinfo;
+
+ /* get the space info for where this inode will be storing its data */
+ data_sinfo = BTRFS_I(inode)->space_info;
+
+ /* make sure we have enough space to handle the data first */
+ spin_lock(&data_sinfo->lock);
+ data_sinfo->bytes_delalloc += bytes;
+
+ /*
+ * we are adding a delalloc extent without calling
+ * btrfs_check_data_free_space first. This happens on a weird
+ * writepage condition, but shouldn't hurt our accounting
+ */
+ if (unlikely(bytes > BTRFS_I(inode)->reserved_bytes)) {
+ data_sinfo->bytes_may_use -= BTRFS_I(inode)->reserved_bytes;
+ BTRFS_I(inode)->reserved_bytes = 0;
+ } else {
+ data_sinfo->bytes_may_use -= bytes;
+ BTRFS_I(inode)->reserved_bytes -= bytes;
+ }
+
+ spin_unlock(&data_sinfo->lock);
+}
+
+/* called when we are clearing an delalloc extent from the inode's io_tree */
+void btrfs_delalloc_free_space(struct btrfs_root *root, struct inode *inode,
+ u64 bytes)
+{
+ struct btrfs_space_info *info;
+
+ info = BTRFS_I(inode)->space_info;
+
+ spin_lock(&info->lock);
+ info->bytes_delalloc -= bytes;
+ spin_unlock(&info->lock);
+}
+
+static int do_chunk_alloc(struct btrfs_trans_handle *trans,
+ struct btrfs_root *extent_root, u64 alloc_bytes,
+ u64 flags, int force)
+{
+ struct btrfs_space_info *space_info;
+ u64 thresh;
+ int ret = 0;
+
+ mutex_lock(&extent_root->fs_info->chunk_mutex);
+
+ flags = btrfs_reduce_alloc_profile(extent_root, flags);
+
+ space_info = __find_space_info(extent_root->fs_info, flags);
+ if (!space_info) {
+ ret = update_space_info(extent_root->fs_info, flags,
+ 0, 0, &space_info);
+ BUG_ON(ret);
+ }
+ BUG_ON(!space_info);
+
+ spin_lock(&space_info->lock);
+ if (space_info->force_alloc) {
+ force = 1;
+ space_info->force_alloc = 0;
+ }
+ if (space_info->full) {
+ spin_unlock(&space_info->lock);
+ goto out;
+ }
+
+ thresh = space_info->total_bytes - space_info->bytes_readonly;
+ thresh = div_factor(thresh, 6);
+ if (!force &&
+ (space_info->bytes_used + space_info->bytes_pinned +
+ space_info->bytes_reserved + alloc_bytes) < thresh) {
+ spin_unlock(&space_info->lock);
+ goto out;
+ }
+ spin_unlock(&space_info->lock);
+
+ ret = btrfs_alloc_chunk(trans, extent_root, flags);
+ if (ret)
+ space_info->full = 1;
+out:
+ mutex_unlock(&extent_root->fs_info->chunk_mutex);
+ return ret;
+}
+
+static int update_block_group(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ u64 bytenr, u64 num_bytes, int alloc,
+ int mark_free)
+{
+ struct btrfs_block_group_cache *cache;
+ struct btrfs_fs_info *info = root->fs_info;
+ u64 total = num_bytes;
+ u64 old_val;
+ u64 byte_in_group;
+
+ while (total) {
+ cache = btrfs_lookup_block_group(info, bytenr);
+ if (!cache)
+ return -1;
+ byte_in_group = bytenr - cache->key.objectid;
+ WARN_ON(byte_in_group > cache->key.offset);
+
+ spin_lock(&cache->space_info->lock);
+ spin_lock(&cache->lock);
+ cache->dirty = 1;
+ old_val = btrfs_block_group_used(&cache->item);
+ num_bytes = min(total, cache->key.offset - byte_in_group);
+ if (alloc) {
+ old_val += num_bytes;
+ cache->space_info->bytes_used += num_bytes;
+ if (cache->ro)
+ cache->space_info->bytes_readonly -= num_bytes;
+ btrfs_set_block_group_used(&cache->item, old_val);
+ spin_unlock(&cache->lock);
+ spin_unlock(&cache->space_info->lock);
+ } else {
+ old_val -= num_bytes;
+ cache->space_info->bytes_used -= num_bytes;
+ if (cache->ro)
+ cache->space_info->bytes_readonly += num_bytes;
+ btrfs_set_block_group_used(&cache->item, old_val);
+ spin_unlock(&cache->lock);
+ spin_unlock(&cache->space_info->lock);
+ if (mark_free) {
+ int ret;
+
+ ret = btrfs_discard_extent(root, bytenr,
+ num_bytes);
+ WARN_ON(ret);
+
+ ret = btrfs_add_free_space(cache, bytenr,
+ num_bytes);
+ WARN_ON(ret);
+ }
+ }
+ put_block_group(cache);
+ total -= num_bytes;
+ bytenr += num_bytes;
+ }
+ return 0;
+}
+
+static u64 first_logical_byte(struct btrfs_root *root, u64 search_start)
+{
+ struct btrfs_block_group_cache *cache;
+ u64 bytenr;
+
+ cache = btrfs_lookup_first_block_group(root->fs_info, search_start);
+ if (!cache)
+ return 0;
+
+ bytenr = cache->key.objectid;
+ put_block_group(cache);
+
+ return bytenr;
+}
+
+int btrfs_update_pinned_extents(struct btrfs_root *root,
+ u64 bytenr, u64 num, int pin)
+{
+ u64 len;
+ struct btrfs_block_group_cache *cache;
+ struct btrfs_fs_info *fs_info = root->fs_info;
+
+ WARN_ON(!mutex_is_locked(&root->fs_info->pinned_mutex));
+ if (pin) {
+ set_extent_dirty(&fs_info->pinned_extents,
+ bytenr, bytenr + num - 1, GFP_NOFS);
+ } else {
+ clear_extent_dirty(&fs_info->pinned_extents,
+ bytenr, bytenr + num - 1, GFP_NOFS);
+ }
+ while (num > 0) {
+ cache = btrfs_lookup_block_group(fs_info, bytenr);
+ BUG_ON(!cache);
+ len = min(num, cache->key.offset -
+ (bytenr - cache->key.objectid));
+ if (pin) {
+ spin_lock(&cache->space_info->lock);
+ spin_lock(&cache->lock);
+ cache->pinned += len;
+ cache->space_info->bytes_pinned += len;
+ spin_unlock(&cache->lock);
+ spin_unlock(&cache->space_info->lock);
+ fs_info->total_pinned += len;
+ } else {
+ spin_lock(&cache->space_info->lock);
+ spin_lock(&cache->lock);
+ cache->pinned -= len;
+ cache->space_info->bytes_pinned -= len;
+ spin_unlock(&cache->lock);
+ spin_unlock(&cache->space_info->lock);
+ fs_info->total_pinned -= len;
+ if (cache->cached)
+ btrfs_add_free_space(cache, bytenr, len);
+ }
+ put_block_group(cache);
+ bytenr += len;
+ num -= len;
+ }
+ return 0;
+}
+
+static int update_reserved_extents(struct btrfs_root *root,
+ u64 bytenr, u64 num, int reserve)
+{
+ u64 len;
+ struct btrfs_block_group_cache *cache;
+ struct btrfs_fs_info *fs_info = root->fs_info;
+
+ while (num > 0) {
+ cache = btrfs_lookup_block_group(fs_info, bytenr);
+ BUG_ON(!cache);
+ len = min(num, cache->key.offset -
+ (bytenr - cache->key.objectid));
+
+ spin_lock(&cache->space_info->lock);
+ spin_lock(&cache->lock);
+ if (reserve) {
+ cache->reserved += len;
+ cache->space_info->bytes_reserved += len;
+ } else {
+ cache->reserved -= len;
+ cache->space_info->bytes_reserved -= len;
+ }
+ spin_unlock(&cache->lock);
+ spin_unlock(&cache->space_info->lock);
+ put_block_group(cache);
+ bytenr += len;
+ num -= len;
+ }
+ return 0;
+}
+
+int btrfs_copy_pinned(struct btrfs_root *root, struct extent_io_tree *copy)
+{
+ u64 last = 0;
+ u64 start;
+ u64 end;
+ struct extent_io_tree *pinned_extents = &root->fs_info->pinned_extents;
+ int ret;
+
+ mutex_lock(&root->fs_info->pinned_mutex);
+ while (1) {
+ ret = find_first_extent_bit(pinned_extents, last,
+ &start, &end, EXTENT_DIRTY);
+ if (ret)
+ break;
+ set_extent_dirty(copy, start, end, GFP_NOFS);
+ last = end + 1;
+ }
+ mutex_unlock(&root->fs_info->pinned_mutex);
+ return 0;
+}
+
+int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct extent_io_tree *unpin)
+{
+ u64 start;
+ u64 end;
+ int ret;
+
+ mutex_lock(&root->fs_info->pinned_mutex);
+ while (1) {
+ ret = find_first_extent_bit(unpin, 0, &start, &end,
+ EXTENT_DIRTY);
+ if (ret)
+ break;
+
+ ret = btrfs_discard_extent(root, start, end + 1 - start);
+
+ btrfs_update_pinned_extents(root, start, end + 1 - start, 0);
+ clear_extent_dirty(unpin, start, end, GFP_NOFS);
+
+ if (need_resched()) {
+ mutex_unlock(&root->fs_info->pinned_mutex);
+ cond_resched();
+ mutex_lock(&root->fs_info->pinned_mutex);
+ }
+ }
+ mutex_unlock(&root->fs_info->pinned_mutex);
+ return ret;
+}
+
+static int finish_current_insert(struct btrfs_trans_handle *trans,
+ struct btrfs_root *extent_root, int all)
+{
+ u64 start;
+ u64 end;
+ u64 priv;
+ u64 search = 0;
+ struct btrfs_fs_info *info = extent_root->fs_info;
+ struct btrfs_path *path;
+ struct pending_extent_op *extent_op, *tmp;
+ struct list_head insert_list, update_list;
+ int ret;
+ int num_inserts = 0, max_inserts, restart = 0;
+
+ path = btrfs_alloc_path();
+ INIT_LIST_HEAD(&insert_list);
+ INIT_LIST_HEAD(&update_list);
+
+ max_inserts = extent_root->leafsize /
+ (2 * sizeof(struct btrfs_key) + 2 * sizeof(struct btrfs_item) +
+ sizeof(struct btrfs_extent_ref) +
+ sizeof(struct btrfs_extent_item));
+again:
+ mutex_lock(&info->extent_ins_mutex);
+ while (1) {
+ ret = find_first_extent_bit(&info->extent_ins, search, &start,
+ &end, EXTENT_WRITEBACK);
+ if (ret) {
+ if (restart && !num_inserts &&
+ list_empty(&update_list)) {
+ restart = 0;
+ search = 0;
+ continue;
+ }
+ break;
+ }
+
+ ret = try_lock_extent(&info->extent_ins, start, end, GFP_NOFS);
+ if (!ret) {
+ if (all)
+ restart = 1;
+ search = end + 1;
+ if (need_resched()) {
+ mutex_unlock(&info->extent_ins_mutex);
+ cond_resched();
+ mutex_lock(&info->extent_ins_mutex);
+ }
+ continue;
+ }
+
+ ret = get_state_private(&info->extent_ins, start, &priv);
+ BUG_ON(ret);
+ extent_op = (struct pending_extent_op *)(unsigned long) priv;
+
+ if (extent_op->type == PENDING_EXTENT_INSERT) {
+ num_inserts++;
+ list_add_tail(&extent_op->list, &insert_list);
+ search = end + 1;
+ if (num_inserts == max_inserts) {
+ restart = 1;
+ break;
+ }
+ } else if (extent_op->type == PENDING_BACKREF_UPDATE) {
+ list_add_tail(&extent_op->list, &update_list);
+ search = end + 1;
+ } else {
+ BUG();
+ }
+ }
+
+ /*
+ * process the update list, clear the writeback bit for it, and if
+ * somebody marked this thing for deletion then just unlock it and be
+ * done, the free_extents will handle it
+ */
+ list_for_each_entry_safe(extent_op, tmp, &update_list, list) {
+ clear_extent_bits(&info->extent_ins, extent_op->bytenr,
+ extent_op->bytenr + extent_op->num_bytes - 1,
+ EXTENT_WRITEBACK, GFP_NOFS);
+ if (extent_op->del) {
+ list_del_init(&extent_op->list);
+ unlock_extent(&info->extent_ins, extent_op->bytenr,
+ extent_op->bytenr + extent_op->num_bytes
+ - 1, GFP_NOFS);
+ kfree(extent_op);
+ }
+ }
+ mutex_unlock(&info->extent_ins_mutex);
+
+ /*
+ * still have things left on the update list, go ahead an update
+ * everything
+ */
+ if (!list_empty(&update_list)) {
+ ret = update_backrefs(trans, extent_root, path, &update_list);
+ BUG_ON(ret);
+
+ /* we may have COW'ed new blocks, so lets start over */
+ if (all)
+ restart = 1;
+ }
+
+ /*
+ * if no inserts need to be done, but we skipped some extents and we
+ * need to make sure everything is cleaned then reset everything and
+ * go back to the beginning
+ */
+ if (!num_inserts && restart) {
+ search = 0;
+ restart = 0;
+ INIT_LIST_HEAD(&update_list);
+ INIT_LIST_HEAD(&insert_list);
+ goto again;
+ } else if (!num_inserts) {
+ goto out;
+ }
+
+ /*
+ * process the insert extents list. Again if we are deleting this
+ * extent, then just unlock it, pin down the bytes if need be, and be
+ * done with it. Saves us from having to actually insert the extent
+ * into the tree and then subsequently come along and delete it
+ */
+ mutex_lock(&info->extent_ins_mutex);
+ list_for_each_entry_safe(extent_op, tmp, &insert_list, list) {
+ clear_extent_bits(&info->extent_ins, extent_op->bytenr,
+ extent_op->bytenr + extent_op->num_bytes - 1,
+ EXTENT_WRITEBACK, GFP_NOFS);
+ if (extent_op->del) {
+ u64 used;
+ list_del_init(&extent_op->list);
+ unlock_extent(&info->extent_ins, extent_op->bytenr,
+ extent_op->bytenr + extent_op->num_bytes
+ - 1, GFP_NOFS);
+
+ mutex_lock(&extent_root->fs_info->pinned_mutex);
+ ret = pin_down_bytes(trans, extent_root,
+ extent_op->bytenr,
+ extent_op->num_bytes, 0);
+ mutex_unlock(&extent_root->fs_info->pinned_mutex);
+
+ spin_lock(&info->delalloc_lock);
+ used = btrfs_super_bytes_used(&info->super_copy);
+ btrfs_set_super_bytes_used(&info->super_copy,
+ used - extent_op->num_bytes);
+ used = btrfs_root_used(&extent_root->root_item);
+ btrfs_set_root_used(&extent_root->root_item,
+ used - extent_op->num_bytes);
+ spin_unlock(&info->delalloc_lock);
+
+ ret = update_block_group(trans, extent_root,
+ extent_op->bytenr,
+ extent_op->num_bytes,
+ 0, ret > 0);
+ BUG_ON(ret);
+ kfree(extent_op);
+ num_inserts--;
+ }
+ }
+ mutex_unlock(&info->extent_ins_mutex);
+
+ ret = insert_extents(trans, extent_root, path, &insert_list,
+ num_inserts);
+ BUG_ON(ret);
+
+ /*
+ * if restart is set for whatever reason we need to go back and start
+ * searching through the pending list again.
+ *
+ * We just inserted some extents, which could have resulted in new
+ * blocks being allocated, which would result in new blocks needing
+ * updates, so if all is set we _must_ restart to get the updated
+ * blocks.
+ */
+ if (restart || all) {
+ INIT_LIST_HEAD(&insert_list);
+ INIT_LIST_HEAD(&update_list);
+ search = 0;
+ restart = 0;
+ num_inserts = 0;
+ goto again;
+ }
+out:
+ btrfs_free_path(path);
+ return 0;
+}
+
+static int pin_down_bytes(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ u64 bytenr, u64 num_bytes, int is_data)
+{
+ int err = 0;
+ struct extent_buffer *buf;
+
+ if (is_data)
+ goto pinit;
+
+ buf = btrfs_find_tree_block(root, bytenr, num_bytes);
+ if (!buf)
+ goto pinit;
+
+ /* we can reuse a block if it hasn't been written
+ * and it is from this transaction. We can't
+ * reuse anything from the tree log root because
+ * it has tiny sub-transactions.
+ */
+ if (btrfs_buffer_uptodate(buf, 0) &&
+ btrfs_try_tree_lock(buf)) {
+ u64 header_owner = btrfs_header_owner(buf);
+ u64 header_transid = btrfs_header_generation(buf);
+ if (header_owner != BTRFS_TREE_LOG_OBJECTID &&
+ header_owner != BTRFS_TREE_RELOC_OBJECTID &&
+ header_transid == trans->transid &&
+ !btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
+ clean_tree_block(NULL, root, buf);
+ btrfs_tree_unlock(buf);
+ free_extent_buffer(buf);
+ return 1;
+ }
+ btrfs_tree_unlock(buf);
+ }
+ free_extent_buffer(buf);
+pinit:
+ btrfs_update_pinned_extents(root, bytenr, num_bytes, 1);
+
+ BUG_ON(err < 0);
+ return 0;
+}
+
+/*
+ * remove an extent from the root, returns 0 on success
+ */
+static int __free_extent(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ u64 bytenr, u64 num_bytes, u64 parent,
+ u64 root_objectid, u64 ref_generation,
+ u64 owner_objectid, int pin, int mark_free)
+{
+ struct btrfs_path *path;
+ struct btrfs_key key;
+ struct btrfs_fs_info *info = root->fs_info;
+ struct btrfs_root *extent_root = info->extent_root;
+ struct extent_buffer *leaf;
+ int ret;
+ int extent_slot = 0;
+ int found_extent = 0;
+ int num_to_del = 1;
+ struct btrfs_extent_item *ei;
+ u32 refs;
+
+ key.objectid = bytenr;
+ btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
+ key.offset = num_bytes;
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ path->reada = 1;
+ ret = lookup_extent_backref(trans, extent_root, path,
+ bytenr, parent, root_objectid,
+ ref_generation, owner_objectid, 1);
+ if (ret == 0) {
+ struct btrfs_key found_key;
+ extent_slot = path->slots[0];
+ while (extent_slot > 0) {
+ extent_slot--;
+ btrfs_item_key_to_cpu(path->nodes[0], &found_key,
+ extent_slot);
+ if (found_key.objectid != bytenr)
+ break;
+ if (found_key.type == BTRFS_EXTENT_ITEM_KEY &&
+ found_key.offset == num_bytes) {
+ found_extent = 1;
+ break;
+ }
+ if (path->slots[0] - extent_slot > 5)
+ break;
+ }
+ if (!found_extent) {
+ ret = remove_extent_backref(trans, extent_root, path);
+ BUG_ON(ret);
+ btrfs_release_path(extent_root, path);
+ ret = btrfs_search_slot(trans, extent_root,
+ &key, path, -1, 1);
+ if (ret) {
+ printk(KERN_ERR "umm, got %d back from search"
+ ", was looking for %llu\n", ret,
+ (unsigned long long)bytenr);
+ btrfs_print_leaf(extent_root, path->nodes[0]);
+ }
+ BUG_ON(ret);
+ extent_slot = path->slots[0];
+ }
+ } else {
+ btrfs_print_leaf(extent_root, path->nodes[0]);
+ WARN_ON(1);
+ printk(KERN_ERR "btrfs unable to find ref byte nr %llu "
+ "root %llu gen %llu owner %llu\n",
+ (unsigned long long)bytenr,
+ (unsigned long long)root_objectid,
+ (unsigned long long)ref_generation,
+ (unsigned long long)owner_objectid);
+ }
+
+ leaf = path->nodes[0];
+ ei = btrfs_item_ptr(leaf, extent_slot,
+ struct btrfs_extent_item);
+ refs = btrfs_extent_refs(leaf, ei);
+ BUG_ON(refs == 0);
+ refs -= 1;
+ btrfs_set_extent_refs(leaf, ei, refs);
+
+ btrfs_mark_buffer_dirty(leaf);
+
+ if (refs == 0 && found_extent && path->slots[0] == extent_slot + 1) {
+ struct btrfs_extent_ref *ref;
+ ref = btrfs_item_ptr(leaf, path->slots[0],
+ struct btrfs_extent_ref);
+ BUG_ON(btrfs_ref_num_refs(leaf, ref) != 1);
+ /* if the back ref and the extent are next to each other
+ * they get deleted below in one shot
+ */
+ path->slots[0] = extent_slot;
+ num_to_del = 2;
+ } else if (found_extent) {
+ /* otherwise delete the extent back ref */
+ ret = remove_extent_backref(trans, extent_root, path);
+ BUG_ON(ret);
+ /* if refs are 0, we need to setup the path for deletion */
+ if (refs == 0) {
+ btrfs_release_path(extent_root, path);
+ ret = btrfs_search_slot(trans, extent_root, &key, path,
+ -1, 1);
+ BUG_ON(ret);
+ }
+ }
+
+ if (refs == 0) {
+ u64 super_used;
+ u64 root_used;
+
+ if (pin) {
+ mutex_lock(&root->fs_info->pinned_mutex);
+ ret = pin_down_bytes(trans, root, bytenr, num_bytes,
+ owner_objectid >= BTRFS_FIRST_FREE_OBJECTID);
+ mutex_unlock(&root->fs_info->pinned_mutex);
+ if (ret > 0)
+ mark_free = 1;
+ BUG_ON(ret < 0);
+ }
+ /* block accounting for super block */
+ spin_lock(&info->delalloc_lock);
+ super_used = btrfs_super_bytes_used(&info->super_copy);
+ btrfs_set_super_bytes_used(&info->super_copy,
+ super_used - num_bytes);
+
+ /* block accounting for root item */
+ root_used = btrfs_root_used(&root->root_item);
+ btrfs_set_root_used(&root->root_item,
+ root_used - num_bytes);
+ spin_unlock(&info->delalloc_lock);
+ ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
+ num_to_del);
+ BUG_ON(ret);
+ btrfs_release_path(extent_root, path);
+
+ if (owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
+ ret = btrfs_del_csums(trans, root, bytenr, num_bytes);
+ BUG_ON(ret);
+ }
+
+ ret = update_block_group(trans, root, bytenr, num_bytes, 0,
+ mark_free);
+ BUG_ON(ret);
+ }
+ btrfs_free_path(path);
+ finish_current_insert(trans, extent_root, 0);
+ return ret;
+}
+
+/*
+ * find all the blocks marked as pending in the radix tree and remove
+ * them from the extent map
+ */
+static int del_pending_extents(struct btrfs_trans_handle *trans,
+ struct btrfs_root *extent_root, int all)
+{
+ int ret;
+ int err = 0;
+ u64 start;
+ u64 end;
+ u64 priv;
+ u64 search = 0;
+ int nr = 0, skipped = 0;
+ struct extent_io_tree *pending_del;
+ struct extent_io_tree *extent_ins;
+ struct pending_extent_op *extent_op;
+ struct btrfs_fs_info *info = extent_root->fs_info;
+ struct list_head delete_list;
+
+ INIT_LIST_HEAD(&delete_list);
+ extent_ins = &extent_root->fs_info->extent_ins;
+ pending_del = &extent_root->fs_info->pending_del;
+
+again:
+ mutex_lock(&info->extent_ins_mutex);
+ while (1) {
+ ret = find_first_extent_bit(pending_del, search, &start, &end,
+ EXTENT_WRITEBACK);
+ if (ret) {
+ if (all && skipped && !nr) {
+ search = 0;
+ skipped = 0;
+ continue;
+ }
+ mutex_unlock(&info->extent_ins_mutex);
+ break;
+ }
+
+ ret = try_lock_extent(extent_ins, start, end, GFP_NOFS);
+ if (!ret) {
+ search = end+1;
+ skipped = 1;
+
+ if (need_resched()) {
+ mutex_unlock(&info->extent_ins_mutex);
+ cond_resched();
+ mutex_lock(&info->extent_ins_mutex);
+ }
+
+ continue;
+ }
+ BUG_ON(ret < 0);
+
+ ret = get_state_private(pending_del, start, &priv);
+ BUG_ON(ret);
+ extent_op = (struct pending_extent_op *)(unsigned long)priv;
+
+ clear_extent_bits(pending_del, start, end, EXTENT_WRITEBACK,
+ GFP_NOFS);
+ if (!test_range_bit(extent_ins, start, end,
+ EXTENT_WRITEBACK, 0)) {
+ list_add_tail(&extent_op->list, &delete_list);
+ nr++;
+ } else {
+ kfree(extent_op);
+
+ ret = get_state_private(&info->extent_ins, start,
+ &priv);
+ BUG_ON(ret);
+ extent_op = (struct pending_extent_op *)
+ (unsigned long)priv;
+
+ clear_extent_bits(&info->extent_ins, start, end,
+ EXTENT_WRITEBACK, GFP_NOFS);
+
+ if (extent_op->type == PENDING_BACKREF_UPDATE) {
+ list_add_tail(&extent_op->list, &delete_list);
+ search = end + 1;
+ nr++;
+ continue;
+ }
+
+ mutex_lock(&extent_root->fs_info->pinned_mutex);
+ ret = pin_down_bytes(trans, extent_root, start,
+ end + 1 - start, 0);
+ mutex_unlock(&extent_root->fs_info->pinned_mutex);
+
+ ret = update_block_group(trans, extent_root, start,
+ end + 1 - start, 0, ret > 0);
+
+ unlock_extent(extent_ins, start, end, GFP_NOFS);
+ BUG_ON(ret);
+ kfree(extent_op);
+ }
+ if (ret)
+ err = ret;
+
+ search = end + 1;
+
+ if (need_resched()) {
+ mutex_unlock(&info->extent_ins_mutex);
+ cond_resched();
+ mutex_lock(&info->extent_ins_mutex);
+ }
+ }
+
+ if (nr) {
+ ret = free_extents(trans, extent_root, &delete_list);
+ BUG_ON(ret);
+ }
+
+ if (all && skipped) {
+ INIT_LIST_HEAD(&delete_list);
+ search = 0;
+ nr = 0;
+ goto again;
+ }
+
+ if (!err)
+ finish_current_insert(trans, extent_root, 0);
+ return err;
+}
+
+/*
+ * remove an extent from the root, returns 0 on success
+ */
+static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ u64 bytenr, u64 num_bytes, u64 parent,
+ u64 root_objectid, u64 ref_generation,
+ u64 owner_objectid, int pin)
+{
+ struct btrfs_root *extent_root = root->fs_info->extent_root;
+ int pending_ret;
+ int ret;
+
+ WARN_ON(num_bytes < root->sectorsize);
+ if (root == extent_root) {
+ struct pending_extent_op *extent_op = NULL;
+
+ mutex_lock(&root->fs_info->extent_ins_mutex);
+ if (test_range_bit(&root->fs_info->extent_ins, bytenr,
+ bytenr + num_bytes - 1, EXTENT_WRITEBACK, 0)) {
+ u64 priv;
+ ret = get_state_private(&root->fs_info->extent_ins,
+ bytenr, &priv);
+ BUG_ON(ret);
+ extent_op = (struct pending_extent_op *)
+ (unsigned long)priv;
+
+ extent_op->del = 1;
+ if (extent_op->type == PENDING_EXTENT_INSERT) {
+ mutex_unlock(&root->fs_info->extent_ins_mutex);
+ return 0;
+ }
+ }
+
+ if (extent_op) {
+ ref_generation = extent_op->orig_generation;
+ parent = extent_op->orig_parent;
+ }
+
+ extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
+ BUG_ON(!extent_op);
+
+ extent_op->type = PENDING_EXTENT_DELETE;
+ extent_op->bytenr = bytenr;
+ extent_op->num_bytes = num_bytes;
+ extent_op->parent = parent;
+ extent_op->orig_parent = parent;
+ extent_op->generation = ref_generation;
+ extent_op->orig_generation = ref_generation;
+ extent_op->level = (int)owner_objectid;
+ INIT_LIST_HEAD(&extent_op->list);
+ extent_op->del = 0;
+
+ set_extent_bits(&root->fs_info->pending_del,
+ bytenr, bytenr + num_bytes - 1,
+ EXTENT_WRITEBACK, GFP_NOFS);
+ set_state_private(&root->fs_info->pending_del,
+ bytenr, (unsigned long)extent_op);
+ mutex_unlock(&root->fs_info->extent_ins_mutex);
+ return 0;
+ }
+ /* if metadata always pin */
+ if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID) {
+ if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
+ mutex_lock(&root->fs_info->pinned_mutex);
+ btrfs_update_pinned_extents(root, bytenr, num_bytes, 1);
+ mutex_unlock(&root->fs_info->pinned_mutex);
+ update_reserved_extents(root, bytenr, num_bytes, 0);
+ return 0;
+ }
+ pin = 1;
+ }
+
+ /* if data pin when any transaction has committed this */
+ if (ref_generation != trans->transid)
+ pin = 1;
+
+ ret = __free_extent(trans, root, bytenr, num_bytes, parent,
+ root_objectid, ref_generation,
+ owner_objectid, pin, pin == 0);
+
+ finish_current_insert(trans, root->fs_info->extent_root, 0);
+ pending_ret = del_pending_extents(trans, root->fs_info->extent_root, 0);
+ return ret ? ret : pending_ret;
+}
+
+int btrfs_free_extent(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ u64 bytenr, u64 num_bytes, u64 parent,
+ u64 root_objectid, u64 ref_generation,
+ u64 owner_objectid, int pin)
+{
+ int ret;
+
+ ret = __btrfs_free_extent(trans, root, bytenr, num_bytes, parent,
+ root_objectid, ref_generation,
+ owner_objectid, pin);
+ return ret;
+}
+
+static u64 stripe_align(struct btrfs_root *root, u64 val)
+{
+ u64 mask = ((u64)root->stripesize - 1);
+ u64 ret = (val + mask) & ~mask;
+ return ret;
+}
+
+/*
+ * walks the btree of allocated extents and find a hole of a given size.
+ * The key ins is changed to record the hole:
+ * ins->objectid == block start
+ * ins->flags = BTRFS_EXTENT_ITEM_KEY
+ * ins->offset == number of blocks
+ * Any available blocks before search_start are skipped.
+ */
+static noinline int find_free_extent(struct btrfs_trans_handle *trans,
+ struct btrfs_root *orig_root,
+ u64 num_bytes, u64 empty_size,
+ u64 search_start, u64 search_end,
+ u64 hint_byte, struct btrfs_key *ins,
+ u64 exclude_start, u64 exclude_nr,
+ int data)
+{
+ int ret = 0;
+ struct btrfs_root *root = orig_root->fs_info->extent_root;
+ u64 total_needed = num_bytes;
+ u64 *last_ptr = NULL;
+ u64 last_wanted = 0;
+ struct btrfs_block_group_cache *block_group = NULL;
+ int chunk_alloc_done = 0;
+ int empty_cluster = 2 * 1024 * 1024;
+ int allowed_chunk_alloc = 0;
+ struct list_head *head = NULL, *cur = NULL;
+ int loop = 0;
+ int extra_loop = 0;
+ struct btrfs_space_info *space_info;
+
+ WARN_ON(num_bytes < root->sectorsize);
+ btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
+ ins->objectid = 0;
+ ins->offset = 0;
+
+ if (orig_root->ref_cows || empty_size)
+ allowed_chunk_alloc = 1;
+
+ if (data & BTRFS_BLOCK_GROUP_METADATA) {
+ last_ptr = &root->fs_info->last_alloc;
+ if (!btrfs_test_opt(root, SSD))
+ empty_cluster = 64 * 1024;
+ }
+
+ if ((data & BTRFS_BLOCK_GROUP_DATA) && btrfs_test_opt(root, SSD))
+ last_ptr = &root->fs_info->last_data_alloc;
+
+ if (last_ptr) {
+ if (*last_ptr) {
+ hint_byte = *last_ptr;
+ last_wanted = *last_ptr;
+ } else
+ empty_size += empty_cluster;
+ } else {
+ empty_cluster = 0;
+ }
+ search_start = max(search_start, first_logical_byte(root, 0));
+ search_start = max(search_start, hint_byte);
+
+ if (last_wanted && search_start != last_wanted) {
+ last_wanted = 0;
+ empty_size += empty_cluster;
+ }
+
+ total_needed += empty_size;
+ block_group = btrfs_lookup_block_group(root->fs_info, search_start);
+ if (!block_group)
+ block_group = btrfs_lookup_first_block_group(root->fs_info,
+ search_start);
+ space_info = __find_space_info(root->fs_info, data);
+
+ down_read(&space_info->groups_sem);
+ while (1) {
+ struct btrfs_free_space *free_space;
+ /*
+ * the only way this happens if our hint points to a block
+ * group thats not of the proper type, while looping this
+ * should never happen
+ */
+ if (empty_size)
+ extra_loop = 1;
+
+ if (!block_group)
+ goto new_group_no_lock;
+
+ if (unlikely(!block_group->cached)) {
+ mutex_lock(&block_group->cache_mutex);
+ ret = cache_block_group(root, block_group);
+ mutex_unlock(&block_group->cache_mutex);
+ if (ret)
+ break;
+ }
+
+ mutex_lock(&block_group->alloc_mutex);
+ if (unlikely(!block_group_bits(block_group, data)))
+ goto new_group;
+
+ if (unlikely(block_group->ro))
+ goto new_group;
+
+ free_space = btrfs_find_free_space(block_group, search_start,
+ total_needed);
+ if (free_space) {
+ u64 start = block_group->key.objectid;
+ u64 end = block_group->key.objectid +
+ block_group->key.offset;
+
+ search_start = stripe_align(root, free_space->offset);
+
+ /* move on to the next group */
+ if (search_start + num_bytes >= search_end)
+ goto new_group;
+
+ /* move on to the next group */
+ if (search_start + num_bytes > end)
+ goto new_group;
+
+ if (last_wanted && search_start != last_wanted) {
+ total_needed += empty_cluster;
+ empty_size += empty_cluster;
+ last_wanted = 0;
+ /*
+ * if search_start is still in this block group
+ * then we just re-search this block group
+ */
+ if (search_start >= start &&
+ search_start < end) {
+ mutex_unlock(&block_group->alloc_mutex);
+ continue;
+ }
+
+ /* else we go to the next block group */
+ goto new_group;
+ }
+
+ if (exclude_nr > 0 &&
+ (search_start + num_bytes > exclude_start &&
+ search_start < exclude_start + exclude_nr)) {
+ search_start = exclude_start + exclude_nr;
+ /*
+ * if search_start is still in this block group
+ * then we just re-search this block group
+ */
+ if (search_start >= start &&
+ search_start < end) {
+ mutex_unlock(&block_group->alloc_mutex);
+ last_wanted = 0;
+ continue;
+ }
+
+ /* else we go to the next block group */
+ goto new_group;
+ }
+
+ ins->objectid = search_start;
+ ins->offset = num_bytes;
+
+ btrfs_remove_free_space_lock(block_group, search_start,
+ num_bytes);
+ /* we are all good, lets return */
+ mutex_unlock(&block_group->alloc_mutex);
+ break;
+ }
+new_group:
+ mutex_unlock(&block_group->alloc_mutex);
+ put_block_group(block_group);
+ block_group = NULL;
+new_group_no_lock:
+ /* don't try to compare new allocations against the
+ * last allocation any more
+ */
+ last_wanted = 0;
+
+ /*
+ * Here's how this works.
+ * loop == 0: we were searching a block group via a hint
+ * and didn't find anything, so we start at
+ * the head of the block groups and keep searching
+ * loop == 1: we're searching through all of the block groups
+ * if we hit the head again we have searched
+ * all of the block groups for this space and we
+ * need to try and allocate, if we cant error out.
+ * loop == 2: we allocated more space and are looping through
+ * all of the block groups again.
+ */
+ if (loop == 0) {
+ head = &space_info->block_groups;
+ cur = head->next;
+ loop++;
+ } else if (loop == 1 && cur == head) {
+ int keep_going;
+
+ /* at this point we give up on the empty_size
+ * allocations and just try to allocate the min
+ * space.
+ *
+ * The extra_loop field was set if an empty_size
+ * allocation was attempted above, and if this
+ * is try we need to try the loop again without
+ * the additional empty_size.
+ */
+ total_needed -= empty_size;
+ empty_size = 0;
+ keep_going = extra_loop;
+ loop++;
+
+ if (allowed_chunk_alloc && !chunk_alloc_done) {
+ up_read(&space_info->groups_sem);
+ ret = do_chunk_alloc(trans, root, num_bytes +
+ 2 * 1024 * 1024, data, 1);
+ down_read(&space_info->groups_sem);
+ if (ret < 0)
+ goto loop_check;
+ head = &space_info->block_groups;
+ /*
+ * we've allocated a new chunk, keep
+ * trying
+ */
+ keep_going = 1;
+ chunk_alloc_done = 1;
+ } else if (!allowed_chunk_alloc) {
+ space_info->force_alloc = 1;
+ }
+loop_check:
+ if (keep_going) {
+ cur = head->next;
+ extra_loop = 0;
+ } else {
+ break;
+ }
+ } else if (cur == head) {
+ break;
+ }
+
+ block_group = list_entry(cur, struct btrfs_block_group_cache,
+ list);
+ atomic_inc(&block_group->count);
+
+ search_start = block_group->key.objectid;
+ cur = cur->next;
+ }
+
+ /* we found what we needed */
+ if (ins->objectid) {
+ if (!(data & BTRFS_BLOCK_GROUP_DATA))
+ trans->block_group = block_group->key.objectid;
+
+ if (last_ptr)
+ *last_ptr = ins->objectid + ins->offset;
+ ret = 0;
+ } else if (!ret) {
+ printk(KERN_ERR "btrfs searching for %llu bytes, "
+ "num_bytes %llu, loop %d, allowed_alloc %d\n",
+ (unsigned long long)total_needed,
+ (unsigned long long)num_bytes,
+ loop, allowed_chunk_alloc);
+ ret = -ENOSPC;
+ }
+ if (block_group)
+ put_block_group(block_group);
+
+ up_read(&space_info->groups_sem);
+ return ret;
+}
+
+static void dump_space_info(struct btrfs_space_info *info, u64 bytes)
+{
+ struct btrfs_block_group_cache *cache;
+
+ printk(KERN_INFO "space_info has %llu free, is %sfull\n",
+ (unsigned long long)(info->total_bytes - info->bytes_used -
+ info->bytes_pinned - info->bytes_reserved),
+ (info->full) ? "" : "not ");
+ printk(KERN_INFO "space_info total=%llu, pinned=%llu, delalloc=%llu,"
+ " may_use=%llu, used=%llu\n", info->total_bytes,
+ info->bytes_pinned, info->bytes_delalloc, info->bytes_may_use,
+ info->bytes_used);
+
+ down_read(&info->groups_sem);
+ list_for_each_entry(cache, &info->block_groups, list) {
+ spin_lock(&cache->lock);
+ printk(KERN_INFO "block group %llu has %llu bytes, %llu used "
+ "%llu pinned %llu reserved\n",
+ (unsigned long long)cache->key.objectid,
+ (unsigned long long)cache->key.offset,
+ (unsigned long long)btrfs_block_group_used(&cache->item),
+ (unsigned long long)cache->pinned,
+ (unsigned long long)cache->reserved);
+ btrfs_dump_free_space(cache, bytes);
+ spin_unlock(&cache->lock);
+ }
+ up_read(&info->groups_sem);
+}
+
+static int __btrfs_reserve_extent(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ u64 num_bytes, u64 min_alloc_size,
+ u64 empty_size, u64 hint_byte,
+ u64 search_end, struct btrfs_key *ins,
+ u64 data)
+{
+ int ret;
+ u64 search_start = 0;
+ struct btrfs_fs_info *info = root->fs_info;
+
+ data = btrfs_get_alloc_profile(root, data);
+again:
+ /*
+ * the only place that sets empty_size is btrfs_realloc_node, which
+ * is not called recursively on allocations
+ */
+ if (empty_size || root->ref_cows) {
+ if (!(data & BTRFS_BLOCK_GROUP_METADATA)) {
+ ret = do_chunk_alloc(trans, root->fs_info->extent_root,
+ 2 * 1024 * 1024,
+ BTRFS_BLOCK_GROUP_METADATA |
+ (info->metadata_alloc_profile &
+ info->avail_metadata_alloc_bits), 0);
+ }
+ ret = do_chunk_alloc(trans, root->fs_info->extent_root,
+ num_bytes + 2 * 1024 * 1024, data, 0);
+ }
+
+ WARN_ON(num_bytes < root->sectorsize);
+ ret = find_free_extent(trans, root, num_bytes, empty_size,
+ search_start, search_end, hint_byte, ins,
+ trans->alloc_exclude_start,
+ trans->alloc_exclude_nr, data);
+
+ if (ret == -ENOSPC && num_bytes > min_alloc_size) {
+ num_bytes = num_bytes >> 1;
+ num_bytes = num_bytes & ~(root->sectorsize - 1);
+ num_bytes = max(num_bytes, min_alloc_size);
+ do_chunk_alloc(trans, root->fs_info->extent_root,
+ num_bytes, data, 1);
+ goto again;
+ }
+ if (ret) {
+ struct btrfs_space_info *sinfo;
+
+ sinfo = __find_space_info(root->fs_info, data);
+ printk(KERN_ERR "btrfs allocation failed flags %llu, "
+ "wanted %llu\n", (unsigned long long)data,
+ (unsigned long long)num_bytes);
+ dump_space_info(sinfo, num_bytes);
+ BUG();
+ }
+
+ return ret;
+}
+
+int btrfs_free_reserved_extent(struct btrfs_root *root, u64 start, u64 len)
+{
+ struct btrfs_block_group_cache *cache;
+ int ret = 0;
+
+ cache = btrfs_lookup_block_group(root->fs_info, start);
+ if (!cache) {
+ printk(KERN_ERR "Unable to find block group for %llu\n",
+ (unsigned long long)start);
+ return -ENOSPC;
+ }
+
+ ret = btrfs_discard_extent(root, start, len);
+
+ btrfs_add_free_space(cache, start, len);
+ put_block_group(cache);
+ update_reserved_extents(root, start, len, 0);
+
+ return ret;
+}
+
+int btrfs_reserve_extent(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ u64 num_bytes, u64 min_alloc_size,
+ u64 empty_size, u64 hint_byte,
+ u64 search_end, struct btrfs_key *ins,
+ u64 data)
+{
+ int ret;
+ ret = __btrfs_reserve_extent(trans, root, num_bytes, min_alloc_size,
+ empty_size, hint_byte, search_end, ins,
+ data);
+ update_reserved_extents(root, ins->objectid, ins->offset, 1);
+ return ret;
+}
+
+static int __btrfs_alloc_reserved_extent(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, u64 parent,
+ u64 root_objectid, u64 ref_generation,
+ u64 owner, struct btrfs_key *ins)
+{
+ int ret;
+ int pending_ret;
+ u64 super_used;
+ u64 root_used;
+ u64 num_bytes = ins->offset;
+ u32 sizes[2];
+ struct btrfs_fs_info *info = root->fs_info;
+ struct btrfs_root *extent_root = info->extent_root;
+ struct btrfs_extent_item *extent_item;
+ struct btrfs_extent_ref *ref;
+ struct btrfs_path *path;
+ struct btrfs_key keys[2];
+
+ if (parent == 0)
+ parent = ins->objectid;
+
+ /* block accounting for super block */
+ spin_lock(&info->delalloc_lock);
+ super_used = btrfs_super_bytes_used(&info->super_copy);
+ btrfs_set_super_bytes_used(&info->super_copy, super_used + num_bytes);
+
+ /* block accounting for root item */
+ root_used = btrfs_root_used(&root->root_item);
+ btrfs_set_root_used(&root->root_item, root_used + num_bytes);
+ spin_unlock(&info->delalloc_lock);
+
+ if (root == extent_root) {
+ struct pending_extent_op *extent_op;
+
+ extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
+ BUG_ON(!extent_op);
+
+ extent_op->type = PENDING_EXTENT_INSERT;
+ extent_op->bytenr = ins->objectid;
+ extent_op->num_bytes = ins->offset;
+ extent_op->parent = parent;
+ extent_op->orig_parent = 0;
+ extent_op->generation = ref_generation;
+ extent_op->orig_generation = 0;
+ extent_op->level = (int)owner;
+ INIT_LIST_HEAD(&extent_op->list);
+ extent_op->del = 0;
+
+ mutex_lock(&root->fs_info->extent_ins_mutex);
+ set_extent_bits(&root->fs_info->extent_ins, ins->objectid,
+ ins->objectid + ins->offset - 1,
+ EXTENT_WRITEBACK, GFP_NOFS);
+ set_state_private(&root->fs_info->extent_ins,
+ ins->objectid, (unsigned long)extent_op);
+ mutex_unlock(&root->fs_info->extent_ins_mutex);
+ goto update_block;
+ }
+
+ memcpy(&keys[0], ins, sizeof(*ins));
+ keys[1].objectid = ins->objectid;
+ keys[1].type = BTRFS_EXTENT_REF_KEY;
+ keys[1].offset = parent;
+ sizes[0] = sizeof(*extent_item);
+ sizes[1] = sizeof(*ref);
+
+ path = btrfs_alloc_path();
+ BUG_ON(!path);
+
+ ret = btrfs_insert_empty_items(trans, extent_root, path, keys,
+ sizes, 2);
+ BUG_ON(ret);
+
+ extent_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
+ struct btrfs_extent_item);
+ btrfs_set_extent_refs(path->nodes[0], extent_item, 1);
+ ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,
+ struct btrfs_extent_ref);
+
+ btrfs_set_ref_root(path->nodes[0], ref, root_objectid);
+ btrfs_set_ref_generation(path->nodes[0], ref, ref_generation);
+ btrfs_set_ref_objectid(path->nodes[0], ref, owner);
+ btrfs_set_ref_num_refs(path->nodes[0], ref, 1);
+
+ btrfs_mark_buffer_dirty(path->nodes[0]);
+
+ trans->alloc_exclude_start = 0;
+ trans->alloc_exclude_nr = 0;
+ btrfs_free_path(path);
+ finish_current_insert(trans, extent_root, 0);
+ pending_ret = del_pending_extents(trans, extent_root, 0);
+
+ if (ret)
+ goto out;
+ if (pending_ret) {
+ ret = pending_ret;
+ goto out;
+ }
+
+update_block:
+ ret = update_block_group(trans, root, ins->objectid,
+ ins->offset, 1, 0);
+ if (ret) {
+ printk(KERN_ERR "btrfs update block group failed for %llu "
+ "%llu\n", (unsigned long long)ins->objectid,
+ (unsigned long long)ins->offset);
+ BUG();
+ }
+out:
+ return ret;
+}
+
+int btrfs_alloc_reserved_extent(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, u64 parent,
+ u64 root_objectid, u64 ref_generation,
+ u64 owner, struct btrfs_key *ins)
+{
+ int ret;
+
+ if (root_objectid == BTRFS_TREE_LOG_OBJECTID)
+ return 0;
+ ret = __btrfs_alloc_reserved_extent(trans, root, parent, root_objectid,
+ ref_generation, owner, ins);
+ update_reserved_extents(root, ins->objectid, ins->offset, 0);
+ return ret;
+}
+
+/*
+ * this is used by the tree logging recovery code. It records that
+ * an extent has been allocated and makes sure to clear the free
+ * space cache bits as well
+ */
+int btrfs_alloc_logged_extent(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, u64 parent,
+ u64 root_objectid, u64 ref_generation,
+ u64 owner, struct btrfs_key *ins)
+{
+ int ret;
+ struct btrfs_block_group_cache *block_group;
+
+ block_group = btrfs_lookup_block_group(root->fs_info, ins->objectid);
+ mutex_lock(&block_group->cache_mutex);
+ cache_block_group(root, block_group);
+ mutex_unlock(&block_group->cache_mutex);
+
+ ret = btrfs_remove_free_space(block_group, ins->objectid,
+ ins->offset);
+ BUG_ON(ret);
+ put_block_group(block_group);
+ ret = __btrfs_alloc_reserved_extent(trans, root, parent, root_objectid,
+ ref_generation, owner, ins);
+ return ret;
}
-static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
+/*
+ * finds a free extent and does all the dirty work required for allocation
+ * returns the key for the extent through ins, and a tree buffer for
+ * the first block of the extent through buf.
+ *
+ * returns 0 if everything worked, non-zero otherwise.
+ */
+int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ u64 num_bytes, u64 parent, u64 min_alloc_size,
+ u64 root_objectid, u64 ref_generation,
+ u64 owner_objectid, u64 empty_size, u64 hint_byte,
+ u64 search_end, struct btrfs_key *ins, u64 data)
{
- u64 extra_flags = flags & (BTRFS_BLOCK_GROUP_RAID0 |
- BTRFS_BLOCK_GROUP_RAID1 |
- BTRFS_BLOCK_GROUP_RAID10 |
- BTRFS_BLOCK_GROUP_DUP);
- if (extra_flags) {
- if (flags & BTRFS_BLOCK_GROUP_DATA)
- fs_info->avail_data_alloc_bits |= extra_flags;
- if (flags & BTRFS_BLOCK_GROUP_METADATA)
- fs_info->avail_metadata_alloc_bits |= extra_flags;
- if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
- fs_info->avail_system_alloc_bits |= extra_flags;
+ int ret;
+
+ ret = __btrfs_reserve_extent(trans, root, num_bytes,
+ min_alloc_size, empty_size, hint_byte,
+ search_end, ins, data);
+ BUG_ON(ret);
+ if (root_objectid != BTRFS_TREE_LOG_OBJECTID) {
+ ret = __btrfs_alloc_reserved_extent(trans, root, parent,
+ root_objectid, ref_generation,
+ owner_objectid, ins);
+ BUG_ON(ret);
+
+ } else {
+ update_reserved_extents(root, ins->objectid, ins->offset, 1);
}
+ return ret;
}
-static u64 reduce_alloc_profile(struct btrfs_root *root, u64 flags)
+struct extent_buffer *btrfs_init_new_buffer(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ u64 bytenr, u32 blocksize,
+ int level)
{
- u64 num_devices = root->fs_info->fs_devices->num_devices;
+ struct extent_buffer *buf;
- if (num_devices == 1)
- flags &= ~(BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID0);
- if (num_devices < 4)
- flags &= ~BTRFS_BLOCK_GROUP_RAID10;
+ buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
+ if (!buf)
+ return ERR_PTR(-ENOMEM);
+ btrfs_set_header_generation(buf, trans->transid);
+ btrfs_set_buffer_lockdep_class(buf, level);
+ btrfs_tree_lock(buf);
+ clean_tree_block(trans, root, buf);
- if ((flags & BTRFS_BLOCK_GROUP_DUP) &&
- (flags & (BTRFS_BLOCK_GROUP_RAID1 |
- BTRFS_BLOCK_GROUP_RAID10))) {
- flags &= ~BTRFS_BLOCK_GROUP_DUP;
+ btrfs_set_lock_blocking(buf);
+ btrfs_set_buffer_uptodate(buf);
+
+ if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
+ set_extent_dirty(&root->dirty_log_pages, buf->start,
+ buf->start + buf->len - 1, GFP_NOFS);
+ } else {
+ set_extent_dirty(&trans->transaction->dirty_pages, buf->start,
+ buf->start + buf->len - 1, GFP_NOFS);
}
+ trans->blocks_used++;
+ /* this returns a buffer locked for blocking */
+ return buf;
+}
- if ((flags & BTRFS_BLOCK_GROUP_RAID1) &&
- (flags & BTRFS_BLOCK_GROUP_RAID10)) {
- flags &= ~BTRFS_BLOCK_GROUP_RAID1;
+/*
+ * helper function to allocate a block for a given tree
+ * returns the tree buffer or NULL.
+ */
+struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ u32 blocksize, u64 parent,
+ u64 root_objectid,
+ u64 ref_generation,
+ int level,
+ u64 hint,
+ u64 empty_size)
+{
+ struct btrfs_key ins;
+ int ret;
+ struct extent_buffer *buf;
+
+ ret = btrfs_alloc_extent(trans, root, blocksize, parent, blocksize,
+ root_objectid, ref_generation, level,
+ empty_size, hint, (u64)-1, &ins, 0);
+ if (ret) {
+ BUG_ON(ret > 0);
+ return ERR_PTR(ret);
}
- if ((flags & BTRFS_BLOCK_GROUP_RAID0) &&
- ((flags & BTRFS_BLOCK_GROUP_RAID1) |
- (flags & BTRFS_BLOCK_GROUP_RAID10) |
- (flags & BTRFS_BLOCK_GROUP_DUP)))
- flags &= ~BTRFS_BLOCK_GROUP_RAID0;
- return flags;
+ buf = btrfs_init_new_buffer(trans, root, ins.objectid,
+ blocksize, level);
+ return buf;
}
-static int do_chunk_alloc(struct btrfs_trans_handle *trans,
- struct btrfs_root *extent_root, u64 alloc_bytes,
- u64 flags, int force)
+int btrfs_drop_leaf_ref(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, struct extent_buffer *leaf)
{
- struct btrfs_space_info *space_info;
- u64 thresh;
- u64 start;
- u64 num_bytes;
+ u64 leaf_owner;
+ u64 leaf_generation;
+ struct refsort *sorted;
+ struct btrfs_key key;
+ struct btrfs_file_extent_item *fi;
+ int i;
+ int nritems;
int ret;
+ int refi = 0;
+ int slot;
- flags = reduce_alloc_profile(extent_root, flags);
+ BUG_ON(!btrfs_is_leaf(leaf));
+ nritems = btrfs_header_nritems(leaf);
+ leaf_owner = btrfs_header_owner(leaf);
+ leaf_generation = btrfs_header_generation(leaf);
- space_info = __find_space_info(extent_root->fs_info, flags);
- if (!space_info) {
- ret = update_space_info(extent_root->fs_info, flags,
- 0, 0, &space_info);
- BUG_ON(ret);
- }
- BUG_ON(!space_info);
+ sorted = kmalloc(sizeof(*sorted) * nritems, GFP_NOFS);
+ /* we do this loop twice. The first time we build a list
+ * of the extents we have a reference on, then we sort the list
+ * by bytenr. The second time around we actually do the
+ * extent freeing.
+ */
+ for (i = 0; i < nritems; i++) {
+ u64 disk_bytenr;
+ cond_resched();
- if (space_info->force_alloc) {
- force = 1;
- space_info->force_alloc = 0;
+ btrfs_item_key_to_cpu(leaf, &key, i);
+
+ /* only extents have references, skip everything else */
+ if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
+ continue;
+
+ fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
+
+ /* inline extents live in the btree, they don't have refs */
+ if (btrfs_file_extent_type(leaf, fi) ==
+ BTRFS_FILE_EXTENT_INLINE)
+ continue;
+
+ disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
+
+ /* holes don't have refs */
+ if (disk_bytenr == 0)
+ continue;
+
+ sorted[refi].bytenr = disk_bytenr;
+ sorted[refi].slot = i;
+ refi++;
}
- if (space_info->full)
- goto out;
- thresh = div_factor(space_info->total_bytes, 6);
- if (!force &&
- (space_info->bytes_used + space_info->bytes_pinned + alloc_bytes) <
- thresh)
+ if (refi == 0)
goto out;
- mutex_lock(&extent_root->fs_info->chunk_mutex);
- ret = btrfs_alloc_chunk(trans, extent_root, &start, &num_bytes, flags);
- if (ret == -ENOSPC) {
-printk("space info full %Lu\n", flags);
- space_info->full = 1;
- goto out_unlock;
- }
- BUG_ON(ret);
+ sort(sorted, refi, sizeof(struct refsort), refsort_cmp, NULL);
- ret = btrfs_make_block_group(trans, extent_root, 0, flags,
- BTRFS_FIRST_CHUNK_TREE_OBJECTID, start, num_bytes);
- BUG_ON(ret);
-out_unlock:
- mutex_unlock(&extent_root->fs_info->chunk_mutex);
-out:
- return 0;
-}
+ for (i = 0; i < refi; i++) {
+ u64 disk_bytenr;
-static int update_block_group(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- u64 bytenr, u64 num_bytes, int alloc,
- int mark_free)
-{
- struct btrfs_block_group_cache *cache;
- struct btrfs_fs_info *info = root->fs_info;
- u64 total = num_bytes;
- u64 old_val;
- u64 byte_in_group;
- u64 start;
- u64 end;
+ disk_bytenr = sorted[i].bytenr;
+ slot = sorted[i].slot;
- WARN_ON(!mutex_is_locked(&root->fs_info->alloc_mutex));
- while(total) {
- cache = btrfs_lookup_block_group(info, bytenr);
- if (!cache) {
- return -1;
- }
- byte_in_group = bytenr - cache->key.objectid;
- WARN_ON(byte_in_group > cache->key.offset);
- start = cache->key.objectid;
- end = start + cache->key.offset - 1;
- set_extent_bits(&info->block_group_cache, start, end,
- BLOCK_GROUP_DIRTY, GFP_NOFS);
+ cond_resched();
- spin_lock(&cache->lock);
- old_val = btrfs_block_group_used(&cache->item);
- num_bytes = min(total, cache->key.offset - byte_in_group);
- if (alloc) {
- old_val += num_bytes;
- cache->space_info->bytes_used += num_bytes;
- btrfs_set_block_group_used(&cache->item, old_val);
- spin_unlock(&cache->lock);
- } else {
- old_val -= num_bytes;
- cache->space_info->bytes_used -= num_bytes;
- btrfs_set_block_group_used(&cache->item, old_val);
- spin_unlock(&cache->lock);
- if (mark_free) {
- set_extent_dirty(&info->free_space_cache,
- bytenr, bytenr + num_bytes - 1,
- GFP_NOFS);
- }
- }
- total -= num_bytes;
- bytenr += num_bytes;
+ btrfs_item_key_to_cpu(leaf, &key, slot);
+ if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
+ continue;
+
+ fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
+
+ ret = __btrfs_free_extent(trans, root, disk_bytenr,
+ btrfs_file_extent_disk_num_bytes(leaf, fi),
+ leaf->start, leaf_owner, leaf_generation,
+ key.objectid, 0);
+ BUG_ON(ret);
+
+ atomic_inc(&root->fs_info->throttle_gen);
+ wake_up(&root->fs_info->transaction_throttle);
+ cond_resched();
}
+out:
+ kfree(sorted);
return 0;
}
-static u64 first_logical_byte(struct btrfs_root *root, u64 search_start)
+static noinline int cache_drop_leaf_ref(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_leaf_ref *ref)
{
- u64 start;
- u64 end;
+ int i;
int ret;
- ret = find_first_extent_bit(&root->fs_info->block_group_cache,
- search_start, &start, &end,
- BLOCK_GROUP_DATA | BLOCK_GROUP_METADATA |
- BLOCK_GROUP_SYSTEM);
- if (ret)
- return 0;
- return start;
-}
-
+ struct btrfs_extent_info *info;
+ struct refsort *sorted;
-static int update_pinned_extents(struct btrfs_root *root,
- u64 bytenr, u64 num, int pin)
-{
- u64 len;
- struct btrfs_block_group_cache *cache;
- struct btrfs_fs_info *fs_info = root->fs_info;
+ if (ref->nritems == 0)
+ return 0;
- WARN_ON(!mutex_is_locked(&root->fs_info->alloc_mutex));
- if (pin) {
- set_extent_dirty(&fs_info->pinned_extents,
- bytenr, bytenr + num - 1, GFP_NOFS);
- } else {
- clear_extent_dirty(&fs_info->pinned_extents,
- bytenr, bytenr + num - 1, GFP_NOFS);
- }
- while (num > 0) {
- cache = btrfs_lookup_block_group(fs_info, bytenr);
- if (!cache) {
- u64 first = first_logical_byte(root, bytenr);
- WARN_ON(first < bytenr);
- len = min(first - bytenr, num);
- } else {
- len = min(num, cache->key.offset -
- (bytenr - cache->key.objectid));
- }
- if (pin) {
- if (cache) {
- spin_lock(&cache->lock);
- cache->pinned += len;
- cache->space_info->bytes_pinned += len;
- spin_unlock(&cache->lock);
- }
- fs_info->total_pinned += len;
- } else {
- if (cache) {
- spin_lock(&cache->lock);
- cache->pinned -= len;
- cache->space_info->bytes_pinned -= len;
- spin_unlock(&cache->lock);
- }
- fs_info->total_pinned -= len;
- }
- bytenr += len;
- num -= len;
+ sorted = kmalloc(sizeof(*sorted) * ref->nritems, GFP_NOFS);
+ for (i = 0; i < ref->nritems; i++) {
+ sorted[i].bytenr = ref->extents[i].bytenr;
+ sorted[i].slot = i;
}
- return 0;
-}
+ sort(sorted, ref->nritems, sizeof(struct refsort), refsort_cmp, NULL);
+
+ /*
+ * the items in the ref were sorted when the ref was inserted
+ * into the ref cache, so this is already in order
+ */
+ for (i = 0; i < ref->nritems; i++) {
+ info = ref->extents + sorted[i].slot;
+ ret = __btrfs_free_extent(trans, root, info->bytenr,
+ info->num_bytes, ref->bytenr,
+ ref->owner, ref->generation,
+ info->objectid, 0);
-int btrfs_copy_pinned(struct btrfs_root *root, struct extent_io_tree *copy)
-{
- u64 last = 0;
- u64 start;
- u64 end;
- struct extent_io_tree *pinned_extents = &root->fs_info->pinned_extents;
- int ret;
+ atomic_inc(&root->fs_info->throttle_gen);
+ wake_up(&root->fs_info->transaction_throttle);
+ cond_resched();
- while(1) {
- ret = find_first_extent_bit(pinned_extents, last,
- &start, &end, EXTENT_DIRTY);
- if (ret)
- break;
- set_extent_dirty(copy, start, end, GFP_NOFS);
- last = end + 1;
+ BUG_ON(ret);
+ info++;
}
+
+ kfree(sorted);
return 0;
}
-int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- struct extent_io_tree *unpin)
+static int drop_snap_lookup_refcount(struct btrfs_root *root, u64 start,
+ u64 len, u32 *refs)
{
- u64 start;
- u64 end;
int ret;
- struct extent_io_tree *free_space_cache;
- free_space_cache = &root->fs_info->free_space_cache;
- mutex_lock(&root->fs_info->alloc_mutex);
- while(1) {
- ret = find_first_extent_bit(unpin, 0, &start, &end,
- EXTENT_DIRTY);
- if (ret)
- break;
- update_pinned_extents(root, start, end + 1 - start, 0);
- clear_extent_dirty(unpin, start, end, GFP_NOFS);
- set_extent_dirty(free_space_cache, start, end, GFP_NOFS);
- if (need_resched()) {
- mutex_unlock(&root->fs_info->alloc_mutex);
- cond_resched();
- mutex_lock(&root->fs_info->alloc_mutex);
+ ret = btrfs_lookup_extent_ref(NULL, root, start, len, refs);
+ BUG_ON(ret);
+
+#if 0 /* some debugging code in case we see problems here */
+ /* if the refs count is one, it won't get increased again. But
+ * if the ref count is > 1, someone may be decreasing it at
+ * the same time we are.
+ */
+ if (*refs != 1) {
+ struct extent_buffer *eb = NULL;
+ eb = btrfs_find_create_tree_block(root, start, len);
+ if (eb)
+ btrfs_tree_lock(eb);
+
+ mutex_lock(&root->fs_info->alloc_mutex);
+ ret = lookup_extent_ref(NULL, root, start, len, refs);
+ BUG_ON(ret);
+ mutex_unlock(&root->fs_info->alloc_mutex);
+
+ if (eb) {
+ btrfs_tree_unlock(eb);
+ free_extent_buffer(eb);
+ }
+ if (*refs == 1) {
+ printk(KERN_ERR "btrfs block %llu went down to one "
+ "during drop_snap\n", (unsigned long long)start);
}
+
}
- mutex_unlock(&root->fs_info->alloc_mutex);
- return 0;
+#endif
+
+ cond_resched();
+ return ret;
}
-static int finish_current_insert(struct btrfs_trans_handle *trans,
- struct btrfs_root *extent_root)
+/*
+ * this is used while deleting old snapshots, and it drops the refs
+ * on a whole subtree starting from a level 1 node.
+ *
+ * The idea is to sort all the leaf pointers, and then drop the
+ * ref on all the leaves in order. Most of the time the leaves
+ * will have ref cache entries, so no leaf IOs will be required to
+ * find the extents they have references on.
+ *
+ * For each leaf, any references it has are also dropped in order
+ *
+ * This ends up dropping the references in something close to optimal
+ * order for reading and modifying the extent allocation tree.
+ */
+static noinline int drop_level_one_refs(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path)
{
- u64 start;
- u64 end;
- struct btrfs_fs_info *info = extent_root->fs_info;
- struct extent_buffer *eb;
- struct btrfs_path *path;
- struct btrfs_key ins;
- struct btrfs_disk_key first;
- struct btrfs_extent_item extent_item;
+ u64 bytenr;
+ u64 root_owner;
+ u64 root_gen;
+ struct extent_buffer *eb = path->nodes[1];
+ struct extent_buffer *leaf;
+ struct btrfs_leaf_ref *ref;
+ struct refsort *sorted = NULL;
+ int nritems = btrfs_header_nritems(eb);
int ret;
- int level;
- int err = 0;
+ int i;
+ int refi = 0;
+ int slot = path->slots[1];
+ u32 blocksize = btrfs_level_size(root, 0);
+ u32 refs;
- WARN_ON(!mutex_is_locked(&extent_root->fs_info->alloc_mutex));
- btrfs_set_stack_extent_refs(&extent_item, 1);
- btrfs_set_key_type(&ins, BTRFS_EXTENT_ITEM_KEY);
- path = btrfs_alloc_path();
+ if (nritems == 0)
+ goto out;
- while(1) {
- ret = find_first_extent_bit(&info->extent_ins, 0, &start,
- &end, EXTENT_LOCKED);
- if (ret)
- break;
+ root_owner = btrfs_header_owner(eb);
+ root_gen = btrfs_header_generation(eb);
+ sorted = kmalloc(sizeof(*sorted) * nritems, GFP_NOFS);
- ins.objectid = start;
- ins.offset = end + 1 - start;
- err = btrfs_insert_item(trans, extent_root, &ins,
- &extent_item, sizeof(extent_item));
- clear_extent_bits(&info->extent_ins, start, end, EXTENT_LOCKED,
- GFP_NOFS);
+ /*
+ * step one, sort all the leaf pointers so we don't scribble
+ * randomly into the extent allocation tree
+ */
+ for (i = slot; i < nritems; i++) {
+ sorted[refi].bytenr = btrfs_node_blockptr(eb, i);
+ sorted[refi].slot = i;
+ refi++;
+ }
- eb = btrfs_find_tree_block(extent_root, ins.objectid,
- ins.offset);
+ /*
+ * nritems won't be zero, but if we're picking up drop_snapshot
+ * after a crash, slot might be > 0, so double check things
+ * just in case.
+ */
+ if (refi == 0)
+ goto out;
- if (!btrfs_buffer_uptodate(eb, trans->transid)) {
- mutex_unlock(&extent_root->fs_info->alloc_mutex);
- btrfs_read_buffer(eb, trans->transid);
- mutex_lock(&extent_root->fs_info->alloc_mutex);
- }
+ sort(sorted, refi, sizeof(struct refsort), refsort_cmp, NULL);
+
+ /*
+ * the first loop frees everything the leaves point to
+ */
+ for (i = 0; i < refi; i++) {
+ u64 ptr_gen;
+
+ bytenr = sorted[i].bytenr;
- btrfs_tree_lock(eb);
- level = btrfs_header_level(eb);
- if (level == 0) {
- btrfs_item_key(eb, &first, 0);
- } else {
- btrfs_node_key(eb, &first, 0);
- }
- btrfs_tree_unlock(eb);
- free_extent_buffer(eb);
/*
- * the first key is just a hint, so the race we've created
- * against reading it is fine
+ * check the reference count on this leaf. If it is > 1
+ * we just decrement it below and don't update any
+ * of the refs the leaf points to.
*/
- err = btrfs_insert_extent_backref(trans, extent_root, path,
- start, extent_root->root_key.objectid,
- 0, level,
- btrfs_disk_key_objectid(&first));
- BUG_ON(err);
- if (need_resched()) {
- mutex_unlock(&extent_root->fs_info->alloc_mutex);
- cond_resched();
- mutex_lock(&extent_root->fs_info->alloc_mutex);
+ ret = drop_snap_lookup_refcount(root, bytenr, blocksize, &refs);
+ BUG_ON(ret);
+ if (refs != 1)
+ continue;
+
+ ptr_gen = btrfs_node_ptr_generation(eb, sorted[i].slot);
+
+ /*
+ * the leaf only had one reference, which means the
+ * only thing pointing to this leaf is the snapshot
+ * we're deleting. It isn't possible for the reference
+ * count to increase again later
+ *
+ * The reference cache is checked for the leaf,
+ * and if found we'll be able to drop any refs held by
+ * the leaf without needing to read it in.
+ */
+ ref = btrfs_lookup_leaf_ref(root, bytenr);
+ if (ref && ref->generation != ptr_gen) {
+ btrfs_free_leaf_ref(root, ref);
+ ref = NULL;
+ }
+ if (ref) {
+ ret = cache_drop_leaf_ref(trans, root, ref);
+ BUG_ON(ret);
+ btrfs_remove_leaf_ref(root, ref);
+ btrfs_free_leaf_ref(root, ref);
+ } else {
+ /*
+ * the leaf wasn't in the reference cache, so
+ * we have to read it.
+ */
+ leaf = read_tree_block(root, bytenr, blocksize,
+ ptr_gen);
+ ret = btrfs_drop_leaf_ref(trans, root, leaf);
+ BUG_ON(ret);
+ free_extent_buffer(leaf);
}
+ atomic_inc(&root->fs_info->throttle_gen);
+ wake_up(&root->fs_info->transaction_throttle);
+ cond_resched();
}
- btrfs_free_path(path);
- return 0;
-}
-static int pin_down_bytes(struct btrfs_root *root, u64 bytenr, u32 num_bytes,
- int pending)
-{
- int err = 0;
+ /*
+ * run through the loop again to free the refs on the leaves.
+ * This is faster than doing it in the loop above because
+ * the leaves are likely to be clustered together. We end up
+ * working in nice chunks on the extent allocation tree.
+ */
+ for (i = 0; i < refi; i++) {
+ bytenr = sorted[i].bytenr;
+ ret = __btrfs_free_extent(trans, root, bytenr,
+ blocksize, eb->start,
+ root_owner, root_gen, 0, 1);
+ BUG_ON(ret);
- WARN_ON(!mutex_is_locked(&root->fs_info->alloc_mutex));
- if (!pending) {
- struct extent_buffer *buf;
- buf = btrfs_find_tree_block(root, bytenr, num_bytes);
- if (buf) {
- if (btrfs_buffer_uptodate(buf, 0) &&
- btrfs_try_tree_lock(buf)) {
- u64 transid =
- root->fs_info->running_transaction->transid;
- u64 header_transid =
- btrfs_header_generation(buf);
- if (header_transid == transid &&
- !btrfs_header_flag(buf,
- BTRFS_HEADER_FLAG_WRITTEN)) {
- clean_tree_block(NULL, root, buf);
- btrfs_tree_unlock(buf);
- free_extent_buffer(buf);
- return 1;
- }
- btrfs_tree_unlock(buf);
- }
- free_extent_buffer(buf);
- }
- update_pinned_extents(root, bytenr, num_bytes, 1);
- } else {
- set_extent_bits(&root->fs_info->pending_del,
- bytenr, bytenr + num_bytes - 1,
- EXTENT_LOCKED, GFP_NOFS);
+ atomic_inc(&root->fs_info->throttle_gen);
+ wake_up(&root->fs_info->transaction_throttle);
+ cond_resched();
}
- BUG_ON(err < 0);
+out:
+ kfree(sorted);
+
+ /*
+ * update the path to show we've processed the entire level 1
+ * node. This will get saved into the root's drop_snapshot_progress
+ * field so these drops are not repeated again if this transaction
+ * commits.
+ */
+ path->slots[1] = nritems;
return 0;
}
/*
- * remove an extent from the root, returns 0 on success
+ * helper function for drop_snapshot, this walks down the tree dropping ref
+ * counts as it goes.
*/
-static int __free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
- *root, u64 bytenr, u64 num_bytes,
- u64 root_objectid, u64 ref_generation,
- u64 owner_objectid, u64 owner_offset, int pin,
- int mark_free)
+static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path, int *level)
{
- struct btrfs_path *path;
- struct btrfs_key key;
- struct btrfs_fs_info *info = root->fs_info;
- struct btrfs_root *extent_root = info->extent_root;
- struct extent_buffer *leaf;
+ u64 root_owner;
+ u64 root_gen;
+ u64 bytenr;
+ u64 ptr_gen;
+ struct extent_buffer *next;
+ struct extent_buffer *cur;
+ struct extent_buffer *parent;
+ u32 blocksize;
int ret;
- int extent_slot = 0;
- int found_extent = 0;
- int num_to_del = 1;
- struct btrfs_extent_item *ei;
u32 refs;
- WARN_ON(!mutex_is_locked(&root->fs_info->alloc_mutex));
- key.objectid = bytenr;
- btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
- key.offset = num_bytes;
- path = btrfs_alloc_path();
- if (!path)
- return -ENOMEM;
+ WARN_ON(*level < 0);
+ WARN_ON(*level >= BTRFS_MAX_LEVEL);
+ ret = drop_snap_lookup_refcount(root, path->nodes[*level]->start,
+ path->nodes[*level]->len, &refs);
+ BUG_ON(ret);
+ if (refs > 1)
+ goto out;
- path->reada = 1;
- ret = lookup_extent_backref(trans, extent_root, path,
- bytenr, root_objectid,
- ref_generation,
- owner_objectid, owner_offset, 1);
- if (ret == 0) {
- struct btrfs_key found_key;
- extent_slot = path->slots[0];
- while(extent_slot > 0) {
- extent_slot--;
- btrfs_item_key_to_cpu(path->nodes[0], &found_key,
- extent_slot);
- if (found_key.objectid != bytenr)
- break;
- if (found_key.type == BTRFS_EXTENT_ITEM_KEY &&
- found_key.offset == num_bytes) {
- found_extent = 1;
- break;
- }
- if (path->slots[0] - extent_slot > 5)
- break;
- }
- if (!found_extent)
- ret = btrfs_del_item(trans, extent_root, path);
- } else {
- btrfs_print_leaf(extent_root, path->nodes[0]);
- WARN_ON(1);
- printk("Unable to find ref byte nr %Lu root %Lu "
- " gen %Lu owner %Lu offset %Lu\n", bytenr,
- root_objectid, ref_generation, owner_objectid,
- owner_offset);
- }
- if (!found_extent) {
- btrfs_release_path(extent_root, path);
- ret = btrfs_search_slot(trans, extent_root, &key, path, -1, 1);
- if (ret < 0)
- return ret;
- BUG_ON(ret);
- extent_slot = path->slots[0];
- }
+ /*
+ * walk down to the last node level and free all the leaves
+ */
+ while (*level >= 0) {
+ WARN_ON(*level < 0);
+ WARN_ON(*level >= BTRFS_MAX_LEVEL);
+ cur = path->nodes[*level];
- leaf = path->nodes[0];
- ei = btrfs_item_ptr(leaf, extent_slot,
- struct btrfs_extent_item);
- refs = btrfs_extent_refs(leaf, ei);
- BUG_ON(refs == 0);
- refs -= 1;
- btrfs_set_extent_refs(leaf, ei, refs);
+ if (btrfs_header_level(cur) != *level)
+ WARN_ON(1);
- btrfs_mark_buffer_dirty(leaf);
+ if (path->slots[*level] >=
+ btrfs_header_nritems(cur))
+ break;
- if (refs == 0 && found_extent && path->slots[0] == extent_slot + 1) {
- /* if the back ref and the extent are next to each other
- * they get deleted below in one shot
+ /* the new code goes down to level 1 and does all the
+ * leaves pointed to that node in bulk. So, this check
+ * for level 0 will always be false.
+ *
+ * But, the disk format allows the drop_snapshot_progress
+ * field in the root to leave things in a state where
+ * a leaf will need cleaning up here. If someone crashes
+ * with the old code and then boots with the new code,
+ * we might find a leaf here.
*/
- path->slots[0] = extent_slot;
- num_to_del = 2;
- } else if (found_extent) {
- /* otherwise delete the extent back ref */
- ret = btrfs_del_item(trans, extent_root, path);
+ if (*level == 0) {
+ ret = btrfs_drop_leaf_ref(trans, root, cur);
+ BUG_ON(ret);
+ break;
+ }
+
+ /*
+ * once we get to level one, process the whole node
+ * at once, including everything below it.
+ */
+ if (*level == 1) {
+ ret = drop_level_one_refs(trans, root, path);
+ BUG_ON(ret);
+ break;
+ }
+
+ bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
+ ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
+ blocksize = btrfs_level_size(root, *level - 1);
+
+ ret = drop_snap_lookup_refcount(root, bytenr, blocksize, &refs);
BUG_ON(ret);
- /* if refs are 0, we need to setup the path for deletion */
- if (refs == 0) {
- btrfs_release_path(extent_root, path);
- ret = btrfs_search_slot(trans, extent_root, &key, path,
- -1, 1);
- if (ret < 0)
- return ret;
+
+ /*
+ * if there is more than one reference, we don't need
+ * to read that node to drop any references it has. We
+ * just drop the ref we hold on that node and move on to the
+ * next slot in this level.
+ */
+ if (refs != 1) {
+ parent = path->nodes[*level];
+ root_owner = btrfs_header_owner(parent);
+ root_gen = btrfs_header_generation(parent);
+ path->slots[*level]++;
+
+ ret = __btrfs_free_extent(trans, root, bytenr,
+ blocksize, parent->start,
+ root_owner, root_gen,
+ *level - 1, 1);
BUG_ON(ret);
- }
- }
- if (refs == 0) {
- u64 super_used;
- u64 root_used;
+ atomic_inc(&root->fs_info->throttle_gen);
+ wake_up(&root->fs_info->transaction_throttle);
+ cond_resched();
- if (pin) {
- ret = pin_down_bytes(root, bytenr, num_bytes, 0);
- if (ret > 0)
- mark_free = 1;
- BUG_ON(ret < 0);
+ continue;
}
- /* block accounting for super block */
- spin_lock_irq(&info->delalloc_lock);
- super_used = btrfs_super_bytes_used(&info->super_copy);
- btrfs_set_super_bytes_used(&info->super_copy,
- super_used - num_bytes);
- spin_unlock_irq(&info->delalloc_lock);
+ /*
+ * we need to keep freeing things in the next level down.
+ * read the block and loop around to process it
+ */
+ next = read_tree_block(root, bytenr, blocksize, ptr_gen);
+ WARN_ON(*level <= 0);
+ if (path->nodes[*level-1])
+ free_extent_buffer(path->nodes[*level-1]);
+ path->nodes[*level-1] = next;
+ *level = btrfs_header_level(next);
+ path->slots[*level] = 0;
+ cond_resched();
+ }
+out:
+ WARN_ON(*level < 0);
+ WARN_ON(*level >= BTRFS_MAX_LEVEL);
- /* block accounting for root item */
- root_used = btrfs_root_used(&root->root_item);
- btrfs_set_root_used(&root->root_item,
- root_used - num_bytes);
- ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
- num_to_del);
- if (ret) {
- return ret;
- }
- ret = update_block_group(trans, root, bytenr, num_bytes, 0,
- mark_free);
- BUG_ON(ret);
+ if (path->nodes[*level] == root->node) {
+ parent = path->nodes[*level];
+ bytenr = path->nodes[*level]->start;
+ } else {
+ parent = path->nodes[*level + 1];
+ bytenr = btrfs_node_blockptr(parent, path->slots[*level + 1]);
}
- btrfs_free_path(path);
- finish_current_insert(trans, extent_root);
- return ret;
+
+ blocksize = btrfs_level_size(root, *level);
+ root_owner = btrfs_header_owner(parent);
+ root_gen = btrfs_header_generation(parent);
+
+ /*
+ * cleanup and free the reference on the last node
+ * we processed
+ */
+ ret = __btrfs_free_extent(trans, root, bytenr, blocksize,
+ parent->start, root_owner, root_gen,
+ *level, 1);
+ free_extent_buffer(path->nodes[*level]);
+ path->nodes[*level] = NULL;
+
+ *level += 1;
+ BUG_ON(ret);
+
+ cond_resched();
+ return 0;
}
/*
- * find all the blocks marked as pending in the radix tree and remove
- * them from the extent map
+ * helper function for drop_subtree, this function is similar to
+ * walk_down_tree. The main difference is that it checks reference
+ * counts while tree blocks are locked.
*/
-static int del_pending_extents(struct btrfs_trans_handle *trans, struct
- btrfs_root *extent_root)
+static noinline int walk_down_subtree(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path, int *level)
{
+ struct extent_buffer *next;
+ struct extent_buffer *cur;
+ struct extent_buffer *parent;
+ u64 bytenr;
+ u64 ptr_gen;
+ u32 blocksize;
+ u32 refs;
int ret;
- int err = 0;
- u64 start;
- u64 end;
- struct extent_io_tree *pending_del;
- struct extent_io_tree *pinned_extents;
- WARN_ON(!mutex_is_locked(&extent_root->fs_info->alloc_mutex));
- pending_del = &extent_root->fs_info->pending_del;
- pinned_extents = &extent_root->fs_info->pinned_extents;
+ cur = path->nodes[*level];
+ ret = btrfs_lookup_extent_ref(trans, root, cur->start, cur->len,
+ &refs);
+ BUG_ON(ret);
+ if (refs > 1)
+ goto out;
- while(1) {
- ret = find_first_extent_bit(pending_del, 0, &start, &end,
- EXTENT_LOCKED);
- if (ret)
+ while (*level >= 0) {
+ cur = path->nodes[*level];
+ if (*level == 0) {
+ ret = btrfs_drop_leaf_ref(trans, root, cur);
+ BUG_ON(ret);
+ clean_tree_block(trans, root, cur);
+ break;
+ }
+ if (path->slots[*level] >= btrfs_header_nritems(cur)) {
+ clean_tree_block(trans, root, cur);
break;
- clear_extent_bits(pending_del, start, end, EXTENT_LOCKED,
- GFP_NOFS);
- if (!test_range_bit(&extent_root->fs_info->extent_ins,
- start, end, EXTENT_LOCKED, 0)) {
- update_pinned_extents(extent_root, start,
- end + 1 - start, 1);
- ret = __free_extent(trans, extent_root,
- start, end + 1 - start,
- extent_root->root_key.objectid,
- 0, 0, 0, 0, 0);
- } else {
- clear_extent_bits(&extent_root->fs_info->extent_ins,
- start, end, EXTENT_LOCKED, GFP_NOFS);
}
- if (ret)
- err = ret;
- if (need_resched()) {
- mutex_unlock(&extent_root->fs_info->alloc_mutex);
- cond_resched();
- mutex_lock(&extent_root->fs_info->alloc_mutex);
+ bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
+ blocksize = btrfs_level_size(root, *level - 1);
+ ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
+
+ next = read_tree_block(root, bytenr, blocksize, ptr_gen);
+ btrfs_tree_lock(next);
+ btrfs_set_lock_blocking(next);
+
+ ret = btrfs_lookup_extent_ref(trans, root, bytenr, blocksize,
+ &refs);
+ BUG_ON(ret);
+ if (refs > 1) {
+ parent = path->nodes[*level];
+ ret = btrfs_free_extent(trans, root, bytenr,
+ blocksize, parent->start,
+ btrfs_header_owner(parent),
+ btrfs_header_generation(parent),
+ *level - 1, 1);
+ BUG_ON(ret);
+ path->slots[*level]++;
+ btrfs_tree_unlock(next);
+ free_extent_buffer(next);
+ continue;
}
+
+ *level = btrfs_header_level(next);
+ path->nodes[*level] = next;
+ path->slots[*level] = 0;
+ path->locks[*level] = 1;
+ cond_resched();
}
- return err;
+out:
+ parent = path->nodes[*level + 1];
+ bytenr = path->nodes[*level]->start;
+ blocksize = path->nodes[*level]->len;
+
+ ret = btrfs_free_extent(trans, root, bytenr, blocksize,
+ parent->start, btrfs_header_owner(parent),
+ btrfs_header_generation(parent), *level, 1);
+ BUG_ON(ret);
+
+ if (path->locks[*level]) {
+ btrfs_tree_unlock(path->nodes[*level]);
+ path->locks[*level] = 0;
+ }
+ free_extent_buffer(path->nodes[*level]);
+ path->nodes[*level] = NULL;
+ *level += 1;
+ cond_resched();
+ return 0;
}
/*
- * remove an extent from the root, returns 0 on success
+ * helper for dropping snapshots. This walks back up the tree in the path
+ * to find the first node higher up where we haven't yet gone through
+ * all the slots
*/
-static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
- struct btrfs_root *root, u64 bytenr,
- u64 num_bytes, u64 root_objectid,
- u64 ref_generation, u64 owner_objectid,
- u64 owner_offset, int pin)
+static noinline int walk_up_tree(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path,
+ int *level, int max_level)
{
- struct btrfs_root *extent_root = root->fs_info->extent_root;
- int pending_ret;
+ u64 root_owner;
+ u64 root_gen;
+ struct btrfs_root_item *root_item = &root->root_item;
+ int i;
+ int slot;
int ret;
- WARN_ON(num_bytes < root->sectorsize);
- if (!root->ref_cows)
- ref_generation = 0;
-
- if (root == extent_root) {
- pin_down_bytes(root, bytenr, num_bytes, 1);
- return 0;
- }
- ret = __free_extent(trans, root, bytenr, num_bytes, root_objectid,
- ref_generation, owner_objectid, owner_offset,
- pin, pin == 0);
+ for (i = *level; i < max_level && path->nodes[i]; i++) {
+ slot = path->slots[i];
+ if (slot < btrfs_header_nritems(path->nodes[i]) - 1) {
+ struct extent_buffer *node;
+ struct btrfs_disk_key disk_key;
- finish_current_insert(trans, root->fs_info->extent_root);
- pending_ret = del_pending_extents(trans, root->fs_info->extent_root);
- return ret ? ret : pending_ret;
-}
+ /*
+ * there is more work to do in this level.
+ * Update the drop_progress marker to reflect
+ * the work we've done so far, and then bump
+ * the slot number
+ */
+ node = path->nodes[i];
+ path->slots[i]++;
+ *level = i;
+ WARN_ON(*level == 0);
+ btrfs_node_key(node, &disk_key, path->slots[i]);
+ memcpy(&root_item->drop_progress,
+ &disk_key, sizeof(disk_key));
+ root_item->drop_level = i;
+ return 0;
+ } else {
+ struct extent_buffer *parent;
-int btrfs_free_extent(struct btrfs_trans_handle *trans,
- struct btrfs_root *root, u64 bytenr,
- u64 num_bytes, u64 root_objectid,
- u64 ref_generation, u64 owner_objectid,
- u64 owner_offset, int pin)
-{
- int ret;
+ /*
+ * this whole node is done, free our reference
+ * on it and go up one level
+ */
+ if (path->nodes[*level] == root->node)
+ parent = path->nodes[*level];
+ else
+ parent = path->nodes[*level + 1];
- maybe_lock_mutex(root);
- ret = __btrfs_free_extent(trans, root, bytenr, num_bytes,
- root_objectid, ref_generation,
- owner_objectid, owner_offset, pin);
- maybe_unlock_mutex(root);
- return ret;
-}
+ root_owner = btrfs_header_owner(parent);
+ root_gen = btrfs_header_generation(parent);
-static u64 stripe_align(struct btrfs_root *root, u64 val)
-{
- u64 mask = ((u64)root->stripesize - 1);
- u64 ret = (val + mask) & ~mask;
- return ret;
+ clean_tree_block(trans, root, path->nodes[*level]);
+ ret = btrfs_free_extent(trans, root,
+ path->nodes[*level]->start,
+ path->nodes[*level]->len,
+ parent->start, root_owner,
+ root_gen, *level, 1);
+ BUG_ON(ret);
+ if (path->locks[*level]) {
+ btrfs_tree_unlock(path->nodes[*level]);
+ path->locks[*level] = 0;
+ }
+ free_extent_buffer(path->nodes[*level]);
+ path->nodes[*level] = NULL;
+ *level = i + 1;
+ }
+ }
+ return 1;
}
/*
- * walks the btree of allocated extents and find a hole of a given size.
- * The key ins is changed to record the hole:
- * ins->objectid == block start
- * ins->flags = BTRFS_EXTENT_ITEM_KEY
- * ins->offset == number of blocks
- * Any available blocks before search_start are skipped.
+ * drop the reference count on the tree rooted at 'snap'. This traverses
+ * the tree freeing any blocks that have a ref count of zero after being
+ * decremented.
*/
-static int noinline find_free_extent(struct btrfs_trans_handle *trans,
- struct btrfs_root *orig_root,
- u64 num_bytes, u64 empty_size,
- u64 search_start, u64 search_end,
- u64 hint_byte, struct btrfs_key *ins,
- u64 exclude_start, u64 exclude_nr,
- int data)
+int btrfs_drop_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root
+ *root)
{
- int ret;
- u64 orig_search_start;
- struct btrfs_root * root = orig_root->fs_info->extent_root;
- struct btrfs_fs_info *info = root->fs_info;
- u64 total_needed = num_bytes;
- u64 *last_ptr = NULL;
- struct btrfs_block_group_cache *block_group;
- int full_scan = 0;
- int wrapped = 0;
- int chunk_alloc_done = 0;
- int empty_cluster = 2 * 1024 * 1024;
- int allowed_chunk_alloc = 0;
+ int ret = 0;
+ int wret;
+ int level;
+ struct btrfs_path *path;
+ int i;
+ int orig_level;
+ struct btrfs_root_item *root_item = &root->root_item;
- WARN_ON(num_bytes < root->sectorsize);
- btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
+ WARN_ON(!mutex_is_locked(&root->fs_info->drop_mutex));
+ path = btrfs_alloc_path();
+ BUG_ON(!path);
- if (orig_root->ref_cows || empty_size)
- allowed_chunk_alloc = 1;
+ level = btrfs_header_level(root->node);
+ orig_level = level;
+ if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
+ path->nodes[level] = root->node;
+ extent_buffer_get(root->node);
+ path->slots[level] = 0;
+ } else {
+ struct btrfs_key key;
+ struct btrfs_disk_key found_key;
+ struct extent_buffer *node;
- if (data & BTRFS_BLOCK_GROUP_METADATA) {
- last_ptr = &root->fs_info->last_alloc;
- empty_cluster = 256 * 1024;
+ btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
+ level = root_item->drop_level;
+ path->lowest_level = level;
+ wret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
+ if (wret < 0) {
+ ret = wret;
+ goto out;
+ }
+ node = path->nodes[level];
+ btrfs_node_key(node, &found_key, path->slots[level]);
+ WARN_ON(memcmp(&found_key, &root_item->drop_progress,
+ sizeof(found_key)));
+ /*
+ * unlock our path, this is safe because only this
+ * function is allowed to delete this snapshot
+ */
+ for (i = 0; i < BTRFS_MAX_LEVEL; i++) {
+ if (path->nodes[i] && path->locks[i]) {
+ path->locks[i] = 0;
+ btrfs_tree_unlock(path->nodes[i]);
+ }
+ }
}
+ while (1) {
+ wret = walk_down_tree(trans, root, path, &level);
+ if (wret > 0)
+ break;
+ if (wret < 0)
+ ret = wret;
- if ((data & BTRFS_BLOCK_GROUP_DATA) && btrfs_test_opt(root, SSD)) {
- last_ptr = &root->fs_info->last_data_alloc;
+ wret = walk_up_tree(trans, root, path, &level,
+ BTRFS_MAX_LEVEL);
+ if (wret > 0)
+ break;
+ if (wret < 0)
+ ret = wret;
+ if (trans->transaction->in_commit) {
+ ret = -EAGAIN;
+ break;
+ }
+ atomic_inc(&root->fs_info->throttle_gen);
+ wake_up(&root->fs_info->transaction_throttle);
}
-
- if (last_ptr) {
- if (*last_ptr)
- hint_byte = *last_ptr;
- else {
- empty_size += empty_cluster;
+ for (i = 0; i <= orig_level; i++) {
+ if (path->nodes[i]) {
+ free_extent_buffer(path->nodes[i]);
+ path->nodes[i] = NULL;
}
}
+out:
+ btrfs_free_path(path);
+ return ret;
+}
- search_start = max(search_start, first_logical_byte(root, 0));
- orig_search_start = search_start;
+int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct extent_buffer *node,
+ struct extent_buffer *parent)
+{
+ struct btrfs_path *path;
+ int level;
+ int parent_level;
+ int ret = 0;
+ int wret;
- if (search_end == (u64)-1)
- search_end = btrfs_super_total_bytes(&info->super_copy);
+ path = btrfs_alloc_path();
+ BUG_ON(!path);
- if (hint_byte) {
- block_group = btrfs_lookup_first_block_group(info, hint_byte);
- if (!block_group)
- hint_byte = search_start;
- block_group = btrfs_find_block_group(root, block_group,
- hint_byte, data, 1);
- if (last_ptr && *last_ptr == 0 && block_group)
- hint_byte = block_group->key.objectid;
- } else {
- block_group = btrfs_find_block_group(root,
- trans->block_group,
- search_start, data, 1);
- }
- search_start = max(search_start, hint_byte);
+ btrfs_assert_tree_locked(parent);
+ parent_level = btrfs_header_level(parent);
+ extent_buffer_get(parent);
+ path->nodes[parent_level] = parent;
+ path->slots[parent_level] = btrfs_header_nritems(parent);
- total_needed += empty_size;
+ btrfs_assert_tree_locked(node);
+ level = btrfs_header_level(node);
+ extent_buffer_get(node);
+ path->nodes[level] = node;
+ path->slots[level] = 0;
-check_failed:
- if (!block_group) {
- block_group = btrfs_lookup_first_block_group(info,
- search_start);
- if (!block_group)
- block_group = btrfs_lookup_first_block_group(info,
- orig_search_start);
- }
- if (full_scan && !chunk_alloc_done) {
- if (allowed_chunk_alloc) {
- do_chunk_alloc(trans, root,
- num_bytes + 2 * 1024 * 1024, data, 1);
- allowed_chunk_alloc = 0;
- } else if (block_group && block_group_bits(block_group, data)) {
- block_group->space_info->force_alloc = 1;
- }
- chunk_alloc_done = 1;
- }
- ret = find_search_start(root, &block_group, &search_start,
- total_needed, data);
- if (ret == -ENOSPC && last_ptr && *last_ptr) {
- *last_ptr = 0;
- block_group = btrfs_lookup_first_block_group(info,
- orig_search_start);
- search_start = orig_search_start;
- ret = find_search_start(root, &block_group, &search_start,
- total_needed, data);
- }
- if (ret == -ENOSPC)
- goto enospc;
- if (ret)
- goto error;
+ while (1) {
+ wret = walk_down_subtree(trans, root, path, &level);
+ if (wret < 0)
+ ret = wret;
+ if (wret != 0)
+ break;
- if (last_ptr && *last_ptr && search_start != *last_ptr) {
- *last_ptr = 0;
- if (!empty_size) {
- empty_size += empty_cluster;
- total_needed += empty_size;
- }
- block_group = btrfs_lookup_first_block_group(info,
- orig_search_start);
- search_start = orig_search_start;
- ret = find_search_start(root, &block_group,
- &search_start, total_needed, data);
- if (ret == -ENOSPC)
- goto enospc;
- if (ret)
- goto error;
+ wret = walk_up_tree(trans, root, path, &level, parent_level);
+ if (wret < 0)
+ ret = wret;
+ if (wret != 0)
+ break;
}
- search_start = stripe_align(root, search_start);
- ins->objectid = search_start;
- ins->offset = num_bytes;
+ btrfs_free_path(path);
+ return ret;
+}
+
+static unsigned long calc_ra(unsigned long start, unsigned long last,
+ unsigned long nr)
+{
+ return min(last, start + nr - 1);
+}
- if (ins->objectid + num_bytes >= search_end)
- goto enospc;
+static noinline int relocate_inode_pages(struct inode *inode, u64 start,
+ u64 len)
+{
+ u64 page_start;
+ u64 page_end;
+ unsigned long first_index;
+ unsigned long last_index;
+ unsigned long i;
+ struct page *page;
+ struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
+ struct file_ra_state *ra;
+ struct btrfs_ordered_extent *ordered;
+ unsigned int total_read = 0;
+ unsigned int total_dirty = 0;
+ int ret = 0;
- if (ins->objectid + num_bytes >
- block_group->key.objectid + block_group->key.offset) {
- search_start = block_group->key.objectid +
- block_group->key.offset;
- goto new_group;
- }
+ ra = kzalloc(sizeof(*ra), GFP_NOFS);
- if (test_range_bit(&info->extent_ins, ins->objectid,
- ins->objectid + num_bytes -1, EXTENT_LOCKED, 0)) {
- search_start = ins->objectid + num_bytes;
- goto new_group;
- }
+ mutex_lock(&inode->i_mutex);
+ first_index = start >> PAGE_CACHE_SHIFT;
+ last_index = (start + len - 1) >> PAGE_CACHE_SHIFT;
- if (test_range_bit(&info->pinned_extents, ins->objectid,
- ins->objectid + num_bytes -1, EXTENT_DIRTY, 0)) {
- search_start = ins->objectid + num_bytes;
- goto new_group;
- }
+ /* make sure the dirty trick played by the caller work */
+ ret = invalidate_inode_pages2_range(inode->i_mapping,
+ first_index, last_index);
+ if (ret)
+ goto out_unlock;
- if (exclude_nr > 0 && (ins->objectid + num_bytes > exclude_start &&
- ins->objectid < exclude_start + exclude_nr)) {
- search_start = exclude_start + exclude_nr;
- goto new_group;
- }
+ file_ra_state_init(ra, inode->i_mapping);
- if (!(data & BTRFS_BLOCK_GROUP_DATA)) {
- block_group = btrfs_lookup_block_group(info, ins->objectid);
- if (block_group)
- trans->block_group = block_group;
- }
- ins->offset = num_bytes;
- if (last_ptr) {
- *last_ptr = ins->objectid + ins->offset;
- if (*last_ptr ==
- btrfs_super_total_bytes(&root->fs_info->super_copy)) {
- *last_ptr = 0;
+ for (i = first_index ; i <= last_index; i++) {
+ if (total_read % ra->ra_pages == 0) {
+ btrfs_force_ra(inode->i_mapping, ra, NULL, i,
+ calc_ra(i, last_index, ra->ra_pages));
}
- }
- return 0;
+ total_read++;
+again:
+ if (((u64)i << PAGE_CACHE_SHIFT) > i_size_read(inode))
+ BUG_ON(1);
+ page = grab_cache_page(inode->i_mapping, i);
+ if (!page) {
+ ret = -ENOMEM;
+ goto out_unlock;
+ }
+ if (!PageUptodate(page)) {
+ btrfs_readpage(NULL, page);
+ lock_page(page);
+ if (!PageUptodate(page)) {
+ unlock_page(page);
+ page_cache_release(page);
+ ret = -EIO;
+ goto out_unlock;
+ }
+ }
+ wait_on_page_writeback(page);
-new_group:
- if (search_start + num_bytes >= search_end) {
-enospc:
- search_start = orig_search_start;
- if (full_scan) {
- ret = -ENOSPC;
- goto error;
+ page_start = (u64)page->index << PAGE_CACHE_SHIFT;
+ page_end = page_start + PAGE_CACHE_SIZE - 1;
+ lock_extent(io_tree, page_start, page_end, GFP_NOFS);
+
+ ordered = btrfs_lookup_ordered_extent(inode, page_start);
+ if (ordered) {
+ unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
+ unlock_page(page);
+ page_cache_release(page);
+ btrfs_start_ordered_extent(inode, ordered, 1);
+ btrfs_put_ordered_extent(ordered);
+ goto again;
}
- if (wrapped) {
- if (!full_scan)
- total_needed -= empty_size;
- full_scan = 1;
- } else
- wrapped = 1;
+ set_page_extent_mapped(page);
+
+ if (i == first_index)
+ set_extent_bits(io_tree, page_start, page_end,
+ EXTENT_BOUNDARY, GFP_NOFS);
+ btrfs_set_extent_delalloc(inode, page_start, page_end);
+
+ set_page_dirty(page);
+ total_dirty++;
+
+ unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
+ unlock_page(page);
+ page_cache_release(page);
}
- block_group = btrfs_lookup_first_block_group(info, search_start);
- cond_resched();
- block_group = btrfs_find_block_group(root, block_group,
- search_start, data, 0);
- goto check_failed;
-error:
+out_unlock:
+ kfree(ra);
+ mutex_unlock(&inode->i_mutex);
+ balance_dirty_pages_ratelimited_nr(inode->i_mapping, total_dirty);
return ret;
}
-static int __btrfs_reserve_extent(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- u64 num_bytes, u64 min_alloc_size,
- u64 empty_size, u64 hint_byte,
- u64 search_end, struct btrfs_key *ins,
- u64 data)
+static noinline int relocate_data_extent(struct inode *reloc_inode,
+ struct btrfs_key *extent_key,
+ u64 offset)
{
- int ret;
- u64 search_start = 0;
- u64 alloc_profile;
- struct btrfs_fs_info *info = root->fs_info;
-
- if (data) {
- alloc_profile = info->avail_data_alloc_bits &
- info->data_alloc_profile;
- data = BTRFS_BLOCK_GROUP_DATA | alloc_profile;
- } else if (root == root->fs_info->chunk_root) {
- alloc_profile = info->avail_system_alloc_bits &
- info->system_alloc_profile;
- data = BTRFS_BLOCK_GROUP_SYSTEM | alloc_profile;
- } else {
- alloc_profile = info->avail_metadata_alloc_bits &
- info->metadata_alloc_profile;
- data = BTRFS_BLOCK_GROUP_METADATA | alloc_profile;
- }
-again:
- data = reduce_alloc_profile(root, data);
- /*
- * the only place that sets empty_size is btrfs_realloc_node, which
- * is not called recursively on allocations
- */
- if (empty_size || root->ref_cows) {
- if (!(data & BTRFS_BLOCK_GROUP_METADATA)) {
- ret = do_chunk_alloc(trans, root->fs_info->extent_root,
- 2 * 1024 * 1024,
- BTRFS_BLOCK_GROUP_METADATA |
- (info->metadata_alloc_profile &
- info->avail_metadata_alloc_bits), 0);
- BUG_ON(ret);
+ struct btrfs_root *root = BTRFS_I(reloc_inode)->root;
+ struct extent_map_tree *em_tree = &BTRFS_I(reloc_inode)->extent_tree;
+ struct extent_map *em;
+ u64 start = extent_key->objectid - offset;
+ u64 end = start + extent_key->offset - 1;
+
+ em = alloc_extent_map(GFP_NOFS);
+ BUG_ON(!em || IS_ERR(em));
+
+ em->start = start;
+ em->len = extent_key->offset;
+ em->block_len = extent_key->offset;
+ em->block_start = extent_key->objectid;
+ em->bdev = root->fs_info->fs_devices->latest_bdev;
+ set_bit(EXTENT_FLAG_PINNED, &em->flags);
+
+ /* setup extent map to cheat btrfs_readpage */
+ lock_extent(&BTRFS_I(reloc_inode)->io_tree, start, end, GFP_NOFS);
+ while (1) {
+ int ret;
+ spin_lock(&em_tree->lock);
+ ret = add_extent_mapping(em_tree, em);
+ spin_unlock(&em_tree->lock);
+ if (ret != -EEXIST) {
+ free_extent_map(em);
+ break;
}
- ret = do_chunk_alloc(trans, root->fs_info->extent_root,
- num_bytes + 2 * 1024 * 1024, data, 0);
- BUG_ON(ret);
+ btrfs_drop_extent_cache(reloc_inode, start, end, 0);
}
+ unlock_extent(&BTRFS_I(reloc_inode)->io_tree, start, end, GFP_NOFS);
- WARN_ON(num_bytes < root->sectorsize);
- ret = find_free_extent(trans, root, num_bytes, empty_size,
- search_start, search_end, hint_byte, ins,
- trans->alloc_exclude_start,
- trans->alloc_exclude_nr, data);
-
- if (ret == -ENOSPC && num_bytes > min_alloc_size) {
- num_bytes = num_bytes >> 1;
- num_bytes = max(num_bytes, min_alloc_size);
- do_chunk_alloc(trans, root->fs_info->extent_root,
- num_bytes, data, 1);
- goto again;
- }
- if (ret) {
- printk("allocation failed flags %Lu\n", data);
- BUG();
- }
- clear_extent_dirty(&root->fs_info->free_space_cache,
- ins->objectid, ins->objectid + ins->offset - 1,
- GFP_NOFS);
- return 0;
+ return relocate_inode_pages(reloc_inode, start, extent_key->offset);
}
-int btrfs_reserve_extent(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- u64 num_bytes, u64 min_alloc_size,
- u64 empty_size, u64 hint_byte,
- u64 search_end, struct btrfs_key *ins,
- u64 data)
+struct btrfs_ref_path {
+ u64 extent_start;
+ u64 nodes[BTRFS_MAX_LEVEL];
+ u64 root_objectid;
+ u64 root_generation;
+ u64 owner_objectid;
+ u32 num_refs;
+ int lowest_level;
+ int current_level;
+ int shared_level;
+
+ struct btrfs_key node_keys[BTRFS_MAX_LEVEL];
+ u64 new_nodes[BTRFS_MAX_LEVEL];
+};
+
+struct disk_extent {
+ u64 ram_bytes;
+ u64 disk_bytenr;
+ u64 disk_num_bytes;
+ u64 offset;
+ u64 num_bytes;
+ u8 compression;
+ u8 encryption;
+ u16 other_encoding;
+};
+
+static int is_cowonly_root(u64 root_objectid)
{
- int ret;
- maybe_lock_mutex(root);
- ret = __btrfs_reserve_extent(trans, root, num_bytes, min_alloc_size,
- empty_size, hint_byte, search_end, ins,
- data);
- maybe_unlock_mutex(root);
- return ret;
+ if (root_objectid == BTRFS_ROOT_TREE_OBJECTID ||
+ root_objectid == BTRFS_EXTENT_TREE_OBJECTID ||
+ root_objectid == BTRFS_CHUNK_TREE_OBJECTID ||
+ root_objectid == BTRFS_DEV_TREE_OBJECTID ||
+ root_objectid == BTRFS_TREE_LOG_OBJECTID ||
+ root_objectid == BTRFS_CSUM_TREE_OBJECTID)
+ return 1;
+ return 0;
}
-static int __btrfs_alloc_reserved_extent(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- u64 root_objectid, u64 ref_generation,
- u64 owner, u64 owner_offset,
- struct btrfs_key *ins)
+static noinline int __next_ref_path(struct btrfs_trans_handle *trans,
+ struct btrfs_root *extent_root,
+ struct btrfs_ref_path *ref_path,
+ int first_time)
{
- int ret;
- int pending_ret;
- u64 super_used;
- u64 root_used;
- u64 num_bytes = ins->offset;
- u32 sizes[2];
- struct btrfs_fs_info *info = root->fs_info;
- struct btrfs_root *extent_root = info->extent_root;
- struct btrfs_extent_item *extent_item;
- struct btrfs_extent_ref *ref;
+ struct extent_buffer *leaf;
struct btrfs_path *path;
- struct btrfs_key keys[2];
+ struct btrfs_extent_ref *ref;
+ struct btrfs_key key;
+ struct btrfs_key found_key;
+ u64 bytenr;
+ u32 nritems;
+ int level;
+ int ret = 1;
- /* block accounting for super block */
- spin_lock_irq(&info->delalloc_lock);
- super_used = btrfs_super_bytes_used(&info->super_copy);
- btrfs_set_super_bytes_used(&info->super_copy, super_used + num_bytes);
- spin_unlock_irq(&info->delalloc_lock);
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
- /* block accounting for root item */
- root_used = btrfs_root_used(&root->root_item);
- btrfs_set_root_used(&root->root_item, root_used + num_bytes);
+ if (first_time) {
+ ref_path->lowest_level = -1;
+ ref_path->current_level = -1;
+ ref_path->shared_level = -1;
+ goto walk_up;
+ }
+walk_down:
+ level = ref_path->current_level - 1;
+ while (level >= -1) {
+ u64 parent;
+ if (level < ref_path->lowest_level)
+ break;
+
+ if (level >= 0)
+ bytenr = ref_path->nodes[level];
+ else
+ bytenr = ref_path->extent_start;
+ BUG_ON(bytenr == 0);
+
+ parent = ref_path->nodes[level + 1];
+ ref_path->nodes[level + 1] = 0;
+ ref_path->current_level = level;
+ BUG_ON(parent == 0);
+
+ key.objectid = bytenr;
+ key.offset = parent + 1;
+ key.type = BTRFS_EXTENT_REF_KEY;
+
+ ret = btrfs_search_slot(trans, extent_root, &key, path, 0, 0);
+ if (ret < 0)
+ goto out;
+ BUG_ON(ret == 0);
+
+ leaf = path->nodes[0];
+ nritems = btrfs_header_nritems(leaf);
+ if (path->slots[0] >= nritems) {
+ ret = btrfs_next_leaf(extent_root, path);
+ if (ret < 0)
+ goto out;
+ if (ret > 0)
+ goto next;
+ leaf = path->nodes[0];
+ }
- if (root == extent_root) {
- set_extent_bits(&root->fs_info->extent_ins, ins->objectid,
- ins->objectid + ins->offset - 1,
- EXTENT_LOCKED, GFP_NOFS);
- goto update_block;
+ btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
+ if (found_key.objectid == bytenr &&
+ found_key.type == BTRFS_EXTENT_REF_KEY) {
+ if (level < ref_path->shared_level)
+ ref_path->shared_level = level;
+ goto found;
+ }
+next:
+ level--;
+ btrfs_release_path(extent_root, path);
+ cond_resched();
}
+ /* reached lowest level */
+ ret = 1;
+ goto out;
+walk_up:
+ level = ref_path->current_level;
+ while (level < BTRFS_MAX_LEVEL - 1) {
+ u64 ref_objectid;
- memcpy(&keys[0], ins, sizeof(*ins));
- keys[1].offset = hash_extent_ref(root_objectid, ref_generation,
- owner, owner_offset);
- keys[1].objectid = ins->objectid;
- keys[1].type = BTRFS_EXTENT_REF_KEY;
- sizes[0] = sizeof(*extent_item);
- sizes[1] = sizeof(*ref);
+ if (level >= 0)
+ bytenr = ref_path->nodes[level];
+ else
+ bytenr = ref_path->extent_start;
- path = btrfs_alloc_path();
- BUG_ON(!path);
+ BUG_ON(bytenr == 0);
- ret = btrfs_insert_empty_items(trans, extent_root, path, keys,
- sizes, 2);
+ key.objectid = bytenr;
+ key.offset = 0;
+ key.type = BTRFS_EXTENT_REF_KEY;
- BUG_ON(ret);
- extent_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
- struct btrfs_extent_item);
- btrfs_set_extent_refs(path->nodes[0], extent_item, 1);
- ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,
- struct btrfs_extent_ref);
+ ret = btrfs_search_slot(trans, extent_root, &key, path, 0, 0);
+ if (ret < 0)
+ goto out;
- btrfs_set_ref_root(path->nodes[0], ref, root_objectid);
- btrfs_set_ref_generation(path->nodes[0], ref, ref_generation);
- btrfs_set_ref_objectid(path->nodes[0], ref, owner);
- btrfs_set_ref_offset(path->nodes[0], ref, owner_offset);
+ leaf = path->nodes[0];
+ nritems = btrfs_header_nritems(leaf);
+ if (path->slots[0] >= nritems) {
+ ret = btrfs_next_leaf(extent_root, path);
+ if (ret < 0)
+ goto out;
+ if (ret > 0) {
+ /* the extent was freed by someone */
+ if (ref_path->lowest_level == level)
+ goto out;
+ btrfs_release_path(extent_root, path);
+ goto walk_down;
+ }
+ leaf = path->nodes[0];
+ }
- btrfs_mark_buffer_dirty(path->nodes[0]);
+ btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
+ if (found_key.objectid != bytenr ||
+ found_key.type != BTRFS_EXTENT_REF_KEY) {
+ /* the extent was freed by someone */
+ if (ref_path->lowest_level == level) {
+ ret = 1;
+ goto out;
+ }
+ btrfs_release_path(extent_root, path);
+ goto walk_down;
+ }
+found:
+ ref = btrfs_item_ptr(leaf, path->slots[0],
+ struct btrfs_extent_ref);
+ ref_objectid = btrfs_ref_objectid(leaf, ref);
+ if (ref_objectid < BTRFS_FIRST_FREE_OBJECTID) {
+ if (first_time) {
+ level = (int)ref_objectid;
+ BUG_ON(level >= BTRFS_MAX_LEVEL);
+ ref_path->lowest_level = level;
+ ref_path->current_level = level;
+ ref_path->nodes[level] = bytenr;
+ } else {
+ WARN_ON(ref_objectid != level);
+ }
+ } else {
+ WARN_ON(level != -1);
+ }
+ first_time = 0;
- trans->alloc_exclude_start = 0;
- trans->alloc_exclude_nr = 0;
- btrfs_free_path(path);
- finish_current_insert(trans, extent_root);
- pending_ret = del_pending_extents(trans, extent_root);
+ if (ref_path->lowest_level == level) {
+ ref_path->owner_objectid = ref_objectid;
+ ref_path->num_refs = btrfs_ref_num_refs(leaf, ref);
+ }
- if (ret)
- goto out;
- if (pending_ret) {
- ret = pending_ret;
- goto out;
- }
+ /*
+ * the block is tree root or the block isn't in reference
+ * counted tree.
+ */
+ if (found_key.objectid == found_key.offset ||
+ is_cowonly_root(btrfs_ref_root(leaf, ref))) {
+ ref_path->root_objectid = btrfs_ref_root(leaf, ref);
+ ref_path->root_generation =
+ btrfs_ref_generation(leaf, ref);
+ if (level < 0) {
+ /* special reference from the tree log */
+ ref_path->nodes[0] = found_key.offset;
+ ref_path->current_level = 0;
+ }
+ ret = 0;
+ goto out;
+ }
-update_block:
- ret = update_block_group(trans, root, ins->objectid, ins->offset, 1, 0);
- if (ret) {
- printk("update block group failed for %Lu %Lu\n",
- ins->objectid, ins->offset);
- BUG();
+ level++;
+ BUG_ON(ref_path->nodes[level] != 0);
+ ref_path->nodes[level] = found_key.offset;
+ ref_path->current_level = level;
+
+ /*
+ * the reference was created in the running transaction,
+ * no need to continue walking up.
+ */
+ if (btrfs_ref_generation(leaf, ref) == trans->transid) {
+ ref_path->root_objectid = btrfs_ref_root(leaf, ref);
+ ref_path->root_generation =
+ btrfs_ref_generation(leaf, ref);
+ ret = 0;
+ goto out;
+ }
+
+ btrfs_release_path(extent_root, path);
+ cond_resched();
}
+ /* reached max tree level, but no tree root found. */
+ BUG();
out:
+ btrfs_free_path(path);
return ret;
}
-int btrfs_alloc_reserved_extent(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- u64 root_objectid, u64 ref_generation,
- u64 owner, u64 owner_offset,
- struct btrfs_key *ins)
-{
- int ret;
- maybe_lock_mutex(root);
- ret = __btrfs_alloc_reserved_extent(trans, root, root_objectid,
- ref_generation, owner,
- owner_offset, ins);
- maybe_unlock_mutex(root);
- return ret;
-}
-/*
- * finds a free extent and does all the dirty work required for allocation
- * returns the key for the extent through ins, and a tree buffer for
- * the first block of the extent through buf.
- *
- * returns 0 if everything worked, non-zero otherwise.
- */
-int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- u64 num_bytes, u64 min_alloc_size,
- u64 root_objectid, u64 ref_generation,
- u64 owner, u64 owner_offset,
- u64 empty_size, u64 hint_byte,
- u64 search_end, struct btrfs_key *ins, u64 data)
+static int btrfs_first_ref_path(struct btrfs_trans_handle *trans,
+ struct btrfs_root *extent_root,
+ struct btrfs_ref_path *ref_path,
+ u64 extent_start)
{
- int ret;
-
- maybe_lock_mutex(root);
+ memset(ref_path, 0, sizeof(*ref_path));
+ ref_path->extent_start = extent_start;
- ret = __btrfs_reserve_extent(trans, root, num_bytes,
- min_alloc_size, empty_size, hint_byte,
- search_end, ins, data);
- BUG_ON(ret);
- ret = __btrfs_alloc_reserved_extent(trans, root, root_objectid,
- ref_generation, owner,
- owner_offset, ins);
- BUG_ON(ret);
+ return __next_ref_path(trans, extent_root, ref_path, 1);
+}
- maybe_unlock_mutex(root);
- return ret;
+static int btrfs_next_ref_path(struct btrfs_trans_handle *trans,
+ struct btrfs_root *extent_root,
+ struct btrfs_ref_path *ref_path)
+{
+ return __next_ref_path(trans, extent_root, ref_path, 0);
}
-/*
- * helper function to allocate a block for a given tree
- * returns the tree buffer or NULL.
- */
-struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- u32 blocksize,
- u64 root_objectid,
- u64 ref_generation,
- u64 first_objectid,
- int level,
- u64 hint,
- u64 empty_size)
+
+static noinline int get_new_locations(struct inode *reloc_inode,
+ struct btrfs_key *extent_key,
+ u64 offset, int no_fragment,
+ struct disk_extent **extents,
+ int *nr_extents)
{
- struct btrfs_key ins;
+ struct btrfs_root *root = BTRFS_I(reloc_inode)->root;
+ struct btrfs_path *path;
+ struct btrfs_file_extent_item *fi;
+ struct extent_buffer *leaf;
+ struct disk_extent *exts = *extents;
+ struct btrfs_key found_key;
+ u64 cur_pos;
+ u64 last_byte;
+ u32 nritems;
+ int nr = 0;
+ int max = *nr_extents;
int ret;
- struct extent_buffer *buf;
- ret = btrfs_alloc_extent(trans, root, blocksize, blocksize,
- root_objectid, ref_generation,
- level, first_objectid, empty_size, hint,
- (u64)-1, &ins, 0);
- if (ret) {
- BUG_ON(ret > 0);
- return ERR_PTR(ret);
- }
- buf = btrfs_find_create_tree_block(root, ins.objectid, blocksize);
- if (!buf) {
- btrfs_free_extent(trans, root, ins.objectid, blocksize,
- root->root_key.objectid, ref_generation,
- 0, 0, 0);
- return ERR_PTR(-ENOMEM);
+ WARN_ON(!no_fragment && *extents);
+ if (!exts) {
+ max = 1;
+ exts = kmalloc(sizeof(*exts) * max, GFP_NOFS);
+ if (!exts)
+ return -ENOMEM;
}
- btrfs_set_header_generation(buf, trans->transid);
- btrfs_tree_lock(buf);
- clean_tree_block(trans, root, buf);
- btrfs_set_buffer_uptodate(buf);
- if (PageDirty(buf->first_page)) {
- printk("page %lu dirty\n", buf->first_page->index);
- WARN_ON(1);
- }
+ path = btrfs_alloc_path();
+ BUG_ON(!path);
- set_extent_dirty(&trans->transaction->dirty_pages, buf->start,
- buf->start + buf->len - 1, GFP_NOFS);
- trans->blocks_used++;
- return buf;
-}
+ cur_pos = extent_key->objectid - offset;
+ last_byte = extent_key->objectid + extent_key->offset;
+ ret = btrfs_lookup_file_extent(NULL, root, path, reloc_inode->i_ino,
+ cur_pos, 0);
+ if (ret < 0)
+ goto out;
+ if (ret > 0) {
+ ret = -ENOENT;
+ goto out;
+ }
-static int noinline drop_leaf_ref_no_cache(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- struct extent_buffer *leaf)
-{
- u64 leaf_owner;
- u64 leaf_generation;
- struct btrfs_key key;
- struct btrfs_file_extent_item *fi;
- int i;
- int nritems;
- int ret;
+ while (1) {
+ leaf = path->nodes[0];
+ nritems = btrfs_header_nritems(leaf);
+ if (path->slots[0] >= nritems) {
+ ret = btrfs_next_leaf(root, path);
+ if (ret < 0)
+ goto out;
+ if (ret > 0)
+ break;
+ leaf = path->nodes[0];
+ }
- BUG_ON(!btrfs_is_leaf(leaf));
- nritems = btrfs_header_nritems(leaf);
- leaf_owner = btrfs_header_owner(leaf);
- leaf_generation = btrfs_header_generation(leaf);
+ btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
+ if (found_key.offset != cur_pos ||
+ found_key.type != BTRFS_EXTENT_DATA_KEY ||
+ found_key.objectid != reloc_inode->i_ino)
+ break;
- mutex_unlock(&root->fs_info->alloc_mutex);
+ fi = btrfs_item_ptr(leaf, path->slots[0],
+ struct btrfs_file_extent_item);
+ if (btrfs_file_extent_type(leaf, fi) !=
+ BTRFS_FILE_EXTENT_REG ||
+ btrfs_file_extent_disk_bytenr(leaf, fi) == 0)
+ break;
- for (i = 0; i < nritems; i++) {
- u64 disk_bytenr;
- cond_resched();
+ if (nr == max) {
+ struct disk_extent *old = exts;
+ max *= 2;
+ exts = kzalloc(sizeof(*exts) * max, GFP_NOFS);
+ memcpy(exts, old, sizeof(*exts) * nr);
+ if (old != *extents)
+ kfree(old);
+ }
- btrfs_item_key_to_cpu(leaf, &key, i);
- if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
- continue;
- fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
- if (btrfs_file_extent_type(leaf, fi) ==
- BTRFS_FILE_EXTENT_INLINE)
- continue;
- /*
- * FIXME make sure to insert a trans record that
- * repeats the snapshot del on crash
- */
- disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
- if (disk_bytenr == 0)
- continue;
+ exts[nr].disk_bytenr =
+ btrfs_file_extent_disk_bytenr(leaf, fi);
+ exts[nr].disk_num_bytes =
+ btrfs_file_extent_disk_num_bytes(leaf, fi);
+ exts[nr].offset = btrfs_file_extent_offset(leaf, fi);
+ exts[nr].num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
+ exts[nr].ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi);
+ exts[nr].compression = btrfs_file_extent_compression(leaf, fi);
+ exts[nr].encryption = btrfs_file_extent_encryption(leaf, fi);
+ exts[nr].other_encoding = btrfs_file_extent_other_encoding(leaf,
+ fi);
+ BUG_ON(exts[nr].offset > 0);
+ BUG_ON(exts[nr].compression || exts[nr].encryption);
+ BUG_ON(exts[nr].num_bytes != exts[nr].disk_num_bytes);
+
+ cur_pos += exts[nr].num_bytes;
+ nr++;
+
+ if (cur_pos + offset >= last_byte)
+ break;
- mutex_lock(&root->fs_info->alloc_mutex);
- ret = __btrfs_free_extent(trans, root, disk_bytenr,
- btrfs_file_extent_disk_num_bytes(leaf, fi),
- leaf_owner, leaf_generation,
- key.objectid, key.offset, 0);
- mutex_unlock(&root->fs_info->alloc_mutex);
- BUG_ON(ret);
+ if (no_fragment) {
+ ret = 1;
+ goto out;
+ }
+ path->slots[0]++;
}
- mutex_lock(&root->fs_info->alloc_mutex);
- return 0;
+ BUG_ON(cur_pos + offset > last_byte);
+ if (cur_pos + offset < last_byte) {
+ ret = -ENOENT;
+ goto out;
+ }
+ ret = 0;
+out:
+ btrfs_free_path(path);
+ if (ret) {
+ if (exts != *extents)
+ kfree(exts);
+ } else {
+ *extents = exts;
+ *nr_extents = nr;
+ }
+ return ret;
}
-static int noinline drop_leaf_ref(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- struct btrfs_leaf_ref *ref)
+static noinline int replace_one_extent(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path,
+ struct btrfs_key *extent_key,
+ struct btrfs_key *leaf_key,
+ struct btrfs_ref_path *ref_path,
+ struct disk_extent *new_extents,
+ int nr_extents)
{
- int i;
+ struct extent_buffer *leaf;
+ struct btrfs_file_extent_item *fi;
+ struct inode *inode = NULL;
+ struct btrfs_key key;
+ u64 lock_start = 0;
+ u64 lock_end = 0;
+ u64 num_bytes;
+ u64 ext_offset;
+ u64 search_end = (u64)-1;
+ u32 nritems;
+ int nr_scaned = 0;
+ int extent_locked = 0;
+ int extent_type;
int ret;
- struct btrfs_extent_info *info = ref->extents;
- mutex_unlock(&root->fs_info->alloc_mutex);
- for (i = 0; i < ref->nritems; i++) {
- mutex_lock(&root->fs_info->alloc_mutex);
- ret = __btrfs_free_extent(trans, root,
- info->bytenr, info->num_bytes,
- ref->owner, ref->generation,
- info->objectid, info->offset, 0);
- mutex_unlock(&root->fs_info->alloc_mutex);
- BUG_ON(ret);
- info++;
+ memcpy(&key, leaf_key, sizeof(key));
+ if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS) {
+ if (key.objectid < ref_path->owner_objectid ||
+ (key.objectid == ref_path->owner_objectid &&
+ key.type < BTRFS_EXTENT_DATA_KEY)) {
+ key.objectid = ref_path->owner_objectid;
+ key.type = BTRFS_EXTENT_DATA_KEY;
+ key.offset = 0;
+ }
}
- mutex_lock(&root->fs_info->alloc_mutex);
- return 0;
-}
+ while (1) {
+ ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
+ if (ret < 0)
+ goto out;
-static void noinline reada_walk_down(struct btrfs_root *root,
- struct extent_buffer *node,
- int slot)
-{
- u64 bytenr;
- u64 last = 0;
- u32 nritems;
- u32 refs;
- u32 blocksize;
- int ret;
- int i;
- int level;
- int skipped = 0;
+ leaf = path->nodes[0];
+ nritems = btrfs_header_nritems(leaf);
+next:
+ if (extent_locked && ret > 0) {
+ /*
+ * the file extent item was modified by someone
+ * before the extent got locked.
+ */
+ unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
+ lock_end, GFP_NOFS);
+ extent_locked = 0;
+ }
+
+ if (path->slots[0] >= nritems) {
+ if (++nr_scaned > 2)
+ break;
+
+ BUG_ON(extent_locked);
+ ret = btrfs_next_leaf(root, path);
+ if (ret < 0)
+ goto out;
+ if (ret > 0)
+ break;
+ leaf = path->nodes[0];
+ nritems = btrfs_header_nritems(leaf);
+ }
- nritems = btrfs_header_nritems(node);
- level = btrfs_header_level(node);
- if (level)
- return;
+ btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
- for (i = slot; i < nritems && skipped < 32; i++) {
- bytenr = btrfs_node_blockptr(node, i);
- if (last && ((bytenr > last && bytenr - last > 32 * 1024) ||
- (last > bytenr && last - bytenr > 32 * 1024))) {
- skipped++;
+ if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS) {
+ if ((key.objectid > ref_path->owner_objectid) ||
+ (key.objectid == ref_path->owner_objectid &&
+ key.type > BTRFS_EXTENT_DATA_KEY) ||
+ key.offset >= search_end)
+ break;
+ }
+
+ if (inode && key.objectid != inode->i_ino) {
+ BUG_ON(extent_locked);
+ btrfs_release_path(root, path);
+ mutex_unlock(&inode->i_mutex);
+ iput(inode);
+ inode = NULL;
continue;
}
- blocksize = btrfs_level_size(root, level - 1);
- if (i != slot) {
- ret = lookup_extent_ref(NULL, root, bytenr,
- blocksize, &refs);
- BUG_ON(ret);
- if (refs != 1) {
- skipped++;
- continue;
- }
+
+ if (key.type != BTRFS_EXTENT_DATA_KEY) {
+ path->slots[0]++;
+ ret = 1;
+ goto next;
+ }
+ fi = btrfs_item_ptr(leaf, path->slots[0],
+ struct btrfs_file_extent_item);
+ extent_type = btrfs_file_extent_type(leaf, fi);
+ if ((extent_type != BTRFS_FILE_EXTENT_REG &&
+ extent_type != BTRFS_FILE_EXTENT_PREALLOC) ||
+ (btrfs_file_extent_disk_bytenr(leaf, fi) !=
+ extent_key->objectid)) {
+ path->slots[0]++;
+ ret = 1;
+ goto next;
}
- ret = readahead_tree_block(root, bytenr, blocksize,
- btrfs_node_ptr_generation(node, i));
- last = bytenr + blocksize;
- cond_resched();
- if (ret)
- break;
- }
-}
-int drop_snap_lookup_refcount(struct btrfs_root *root, u64 start, u64 len,
- u32 *refs)
-{
- int ret;
- mutex_unlock(&root->fs_info->alloc_mutex);
- ret = lookup_extent_ref(NULL, root, start, len, refs);
- cond_resched();
- mutex_lock(&root->fs_info->alloc_mutex);
- return ret;
-}
+ num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
+ ext_offset = btrfs_file_extent_offset(leaf, fi);
-/*
- * helper function for drop_snapshot, this walks down the tree dropping ref
- * counts as it goes.
- */
-static int noinline walk_down_tree(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- struct btrfs_path *path, int *level)
-{
- u64 root_owner;
- u64 root_gen;
- u64 bytenr;
- u64 ptr_gen;
- struct extent_buffer *next;
- struct extent_buffer *cur;
- struct extent_buffer *parent;
- struct btrfs_leaf_ref *ref;
- u32 blocksize;
- int ret;
- u32 refs;
+ if (search_end == (u64)-1) {
+ search_end = key.offset - ext_offset +
+ btrfs_file_extent_ram_bytes(leaf, fi);
+ }
- mutex_lock(&root->fs_info->alloc_mutex);
+ if (!extent_locked) {
+ lock_start = key.offset;
+ lock_end = lock_start + num_bytes - 1;
+ } else {
+ if (lock_start > key.offset ||
+ lock_end + 1 < key.offset + num_bytes) {
+ unlock_extent(&BTRFS_I(inode)->io_tree,
+ lock_start, lock_end, GFP_NOFS);
+ extent_locked = 0;
+ }
+ }
- WARN_ON(*level < 0);
- WARN_ON(*level >= BTRFS_MAX_LEVEL);
- ret = drop_snap_lookup_refcount(root, path->nodes[*level]->start,
- path->nodes[*level]->len, &refs);
- BUG_ON(ret);
- if (refs > 1)
- goto out;
+ if (!inode) {
+ btrfs_release_path(root, path);
- /*
- * walk down to the last node level and free all the leaves
- */
- while(*level >= 0) {
- WARN_ON(*level < 0);
- WARN_ON(*level >= BTRFS_MAX_LEVEL);
- cur = path->nodes[*level];
+ inode = btrfs_iget_locked(root->fs_info->sb,
+ key.objectid, root);
+ if (inode->i_state & I_NEW) {
+ BTRFS_I(inode)->root = root;
+ BTRFS_I(inode)->location.objectid =
+ key.objectid;
+ BTRFS_I(inode)->location.type =
+ BTRFS_INODE_ITEM_KEY;
+ BTRFS_I(inode)->location.offset = 0;
+ btrfs_read_locked_inode(inode);
+ unlock_new_inode(inode);
+ }
+ /*
+ * some code call btrfs_commit_transaction while
+ * holding the i_mutex, so we can't use mutex_lock
+ * here.
+ */
+ if (is_bad_inode(inode) ||
+ !mutex_trylock(&inode->i_mutex)) {
+ iput(inode);
+ inode = NULL;
+ key.offset = (u64)-1;
+ goto skip;
+ }
+ }
- if (btrfs_header_level(cur) != *level)
- WARN_ON(1);
+ if (!extent_locked) {
+ struct btrfs_ordered_extent *ordered;
- if (path->slots[*level] >=
- btrfs_header_nritems(cur))
- break;
- if (*level == 0) {
- ret = drop_leaf_ref_no_cache(trans, root, cur);
- BUG_ON(ret);
- break;
- }
- bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
- ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
- blocksize = btrfs_level_size(root, *level - 1);
+ btrfs_release_path(root, path);
- ret = drop_snap_lookup_refcount(root, bytenr, blocksize, &refs);
- BUG_ON(ret);
- if (refs != 1) {
- parent = path->nodes[*level];
- root_owner = btrfs_header_owner(parent);
- root_gen = btrfs_header_generation(parent);
- path->slots[*level]++;
- ret = __btrfs_free_extent(trans, root, bytenr,
- blocksize, root_owner,
- root_gen, 0, 0, 1);
- BUG_ON(ret);
+ lock_extent(&BTRFS_I(inode)->io_tree, lock_start,
+ lock_end, GFP_NOFS);
+ ordered = btrfs_lookup_first_ordered_extent(inode,
+ lock_end);
+ if (ordered &&
+ ordered->file_offset <= lock_end &&
+ ordered->file_offset + ordered->len > lock_start) {
+ unlock_extent(&BTRFS_I(inode)->io_tree,
+ lock_start, lock_end, GFP_NOFS);
+ btrfs_start_ordered_extent(inode, ordered, 1);
+ btrfs_put_ordered_extent(ordered);
+ key.offset += num_bytes;
+ goto skip;
+ }
+ if (ordered)
+ btrfs_put_ordered_extent(ordered);
+
+ extent_locked = 1;
continue;
}
- if (*level == 1) {
- struct btrfs_key key;
- btrfs_node_key_to_cpu(cur, &key, path->slots[*level]);
- ref = btrfs_lookup_leaf_ref(root, bytenr);
- if (ref) {
- ret = drop_leaf_ref(trans, root, ref);
- BUG_ON(ret);
- btrfs_remove_leaf_ref(root, ref);
- btrfs_free_leaf_ref(ref);
- *level = 0;
- break;
- }
- }
- next = btrfs_find_tree_block(root, bytenr, blocksize);
- if (!next || !btrfs_buffer_uptodate(next, ptr_gen)) {
- free_extent_buffer(next);
- mutex_unlock(&root->fs_info->alloc_mutex);
+ if (nr_extents == 1) {
+ /* update extent pointer in place */
+ btrfs_set_file_extent_disk_bytenr(leaf, fi,
+ new_extents[0].disk_bytenr);
+ btrfs_set_file_extent_disk_num_bytes(leaf, fi,
+ new_extents[0].disk_num_bytes);
+ btrfs_mark_buffer_dirty(leaf);
+
+ btrfs_drop_extent_cache(inode, key.offset,
+ key.offset + num_bytes - 1, 0);
+
+ ret = btrfs_inc_extent_ref(trans, root,
+ new_extents[0].disk_bytenr,
+ new_extents[0].disk_num_bytes,
+ leaf->start,
+ root->root_key.objectid,
+ trans->transid,
+ key.objectid);
+ BUG_ON(ret);
- if (path->slots[*level] == 0)
- reada_walk_down(root, cur, path->slots[*level]);
- next = read_tree_block(root, bytenr, blocksize,
- ptr_gen);
- cond_resched();
- mutex_lock(&root->fs_info->alloc_mutex);
+ ret = btrfs_free_extent(trans, root,
+ extent_key->objectid,
+ extent_key->offset,
+ leaf->start,
+ btrfs_header_owner(leaf),
+ btrfs_header_generation(leaf),
+ key.objectid, 0);
+ BUG_ON(ret);
- /* we've dropped the lock, double check */
- ret = lookup_extent_ref(NULL, root, bytenr, blocksize,
- &refs);
+ btrfs_release_path(root, path);
+ key.offset += num_bytes;
+ } else {
+ BUG_ON(1);
+#if 0
+ u64 alloc_hint;
+ u64 extent_len;
+ int i;
+ /*
+ * drop old extent pointer at first, then insert the
+ * new pointers one bye one
+ */
+ btrfs_release_path(root, path);
+ ret = btrfs_drop_extents(trans, root, inode, key.offset,
+ key.offset + num_bytes,
+ key.offset, &alloc_hint);
BUG_ON(ret);
- if (refs != 1) {
- parent = path->nodes[*level];
- root_owner = btrfs_header_owner(parent);
- root_gen = btrfs_header_generation(parent);
-
- path->slots[*level]++;
- free_extent_buffer(next);
- ret = __btrfs_free_extent(trans, root, bytenr,
- blocksize,
- root_owner,
- root_gen, 0, 0, 1);
- BUG_ON(ret);
- continue;
- }
- }
- WARN_ON(*level <= 0);
- if (path->nodes[*level-1])
- free_extent_buffer(path->nodes[*level-1]);
- path->nodes[*level-1] = next;
- *level = btrfs_header_level(next);
- path->slots[*level] = 0;
- }
-out:
- WARN_ON(*level < 0);
- WARN_ON(*level >= BTRFS_MAX_LEVEL);
- if (path->nodes[*level] == root->node) {
- parent = path->nodes[*level];
- bytenr = path->nodes[*level]->start;
- } else {
- parent = path->nodes[*level + 1];
- bytenr = btrfs_node_blockptr(parent, path->slots[*level + 1]);
- }
+ for (i = 0; i < nr_extents; i++) {
+ if (ext_offset >= new_extents[i].num_bytes) {
+ ext_offset -= new_extents[i].num_bytes;
+ continue;
+ }
+ extent_len = min(new_extents[i].num_bytes -
+ ext_offset, num_bytes);
- blocksize = btrfs_level_size(root, *level);
- root_owner = btrfs_header_owner(parent);
- root_gen = btrfs_header_generation(parent);
+ ret = btrfs_insert_empty_item(trans, root,
+ path, &key,
+ sizeof(*fi));
+ BUG_ON(ret);
- ret = __btrfs_free_extent(trans, root, bytenr, blocksize,
- root_owner, root_gen, 0, 0, 1);
- free_extent_buffer(path->nodes[*level]);
- path->nodes[*level] = NULL;
- *level += 1;
- BUG_ON(ret);
- mutex_unlock(&root->fs_info->alloc_mutex);
- cond_resched();
- return 0;
-}
+ leaf = path->nodes[0];
+ fi = btrfs_item_ptr(leaf, path->slots[0],
+ struct btrfs_file_extent_item);
+ btrfs_set_file_extent_generation(leaf, fi,
+ trans->transid);
+ btrfs_set_file_extent_type(leaf, fi,
+ BTRFS_FILE_EXTENT_REG);
+ btrfs_set_file_extent_disk_bytenr(leaf, fi,
+ new_extents[i].disk_bytenr);
+ btrfs_set_file_extent_disk_num_bytes(leaf, fi,
+ new_extents[i].disk_num_bytes);
+ btrfs_set_file_extent_ram_bytes(leaf, fi,
+ new_extents[i].ram_bytes);
+
+ btrfs_set_file_extent_compression(leaf, fi,
+ new_extents[i].compression);
+ btrfs_set_file_extent_encryption(leaf, fi,
+ new_extents[i].encryption);
+ btrfs_set_file_extent_other_encoding(leaf, fi,
+ new_extents[i].other_encoding);
+
+ btrfs_set_file_extent_num_bytes(leaf, fi,
+ extent_len);
+ ext_offset += new_extents[i].offset;
+ btrfs_set_file_extent_offset(leaf, fi,
+ ext_offset);
+ btrfs_mark_buffer_dirty(leaf);
+
+ btrfs_drop_extent_cache(inode, key.offset,
+ key.offset + extent_len - 1, 0);
+
+ ret = btrfs_inc_extent_ref(trans, root,
+ new_extents[i].disk_bytenr,
+ new_extents[i].disk_num_bytes,
+ leaf->start,
+ root->root_key.objectid,
+ trans->transid, key.objectid);
+ BUG_ON(ret);
+ btrfs_release_path(root, path);
-/*
- * helper for dropping snapshots. This walks back up the tree in the path
- * to find the first node higher up where we haven't yet gone through
- * all the slots
- */
-static int noinline walk_up_tree(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- struct btrfs_path *path, int *level)
-{
- u64 root_owner;
- u64 root_gen;
- struct btrfs_root_item *root_item = &root->root_item;
- int i;
- int slot;
- int ret;
+ inode_add_bytes(inode, extent_len);
- for(i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) {
- slot = path->slots[i];
- if (slot < btrfs_header_nritems(path->nodes[i]) - 1) {
- struct extent_buffer *node;
- struct btrfs_disk_key disk_key;
- node = path->nodes[i];
- path->slots[i]++;
- *level = i;
- WARN_ON(*level == 0);
- btrfs_node_key(node, &disk_key, path->slots[i]);
- memcpy(&root_item->drop_progress,
- &disk_key, sizeof(disk_key));
- root_item->drop_level = i;
- return 0;
- } else {
- if (path->nodes[*level] == root->node) {
- root_owner = root->root_key.objectid;
- root_gen =
- btrfs_header_generation(path->nodes[*level]);
- } else {
- struct extent_buffer *node;
- node = path->nodes[*level + 1];
- root_owner = btrfs_header_owner(node);
- root_gen = btrfs_header_generation(node);
+ ext_offset = 0;
+ num_bytes -= extent_len;
+ key.offset += extent_len;
+
+ if (num_bytes == 0)
+ break;
}
- ret = btrfs_free_extent(trans, root,
- path->nodes[*level]->start,
- path->nodes[*level]->len,
- root_owner, root_gen, 0, 0, 1);
- BUG_ON(ret);
- free_extent_buffer(path->nodes[*level]);
- path->nodes[*level] = NULL;
- *level = i + 1;
+ BUG_ON(i >= nr_extents);
+#endif
+ }
+
+ if (extent_locked) {
+ unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
+ lock_end, GFP_NOFS);
+ extent_locked = 0;
}
+skip:
+ if (ref_path->owner_objectid != BTRFS_MULTIPLE_OBJECTIDS &&
+ key.offset >= search_end)
+ break;
+
+ cond_resched();
}
- return 1;
+ ret = 0;
+out:
+ btrfs_release_path(root, path);
+ if (inode) {
+ mutex_unlock(&inode->i_mutex);
+ if (extent_locked) {
+ unlock_extent(&BTRFS_I(inode)->io_tree, lock_start,
+ lock_end, GFP_NOFS);
+ }
+ iput(inode);
+ }
+ return ret;
}
-/*
- * drop the reference count on the tree rooted at 'snap'. This traverses
- * the tree freeing any blocks that have a ref count of zero after being
- * decremented.
- */
-int btrfs_drop_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root
- *root)
+int btrfs_reloc_tree_cache_ref(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct extent_buffer *buf, u64 orig_start)
{
- int ret = 0;
- int wret;
int level;
- struct btrfs_path *path;
- int i;
- int orig_level;
- struct btrfs_root_item *root_item = &root->root_item;
-
- WARN_ON(!mutex_is_locked(&root->fs_info->drop_mutex));
- path = btrfs_alloc_path();
- BUG_ON(!path);
+ int ret;
- level = btrfs_header_level(root->node);
- orig_level = level;
- if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
- path->nodes[level] = root->node;
- extent_buffer_get(root->node);
- path->slots[level] = 0;
- } else {
- struct btrfs_key key;
- struct btrfs_disk_key found_key;
- struct extent_buffer *node;
+ BUG_ON(btrfs_header_generation(buf) != trans->transid);
+ BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
- btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
- level = root_item->drop_level;
- path->lowest_level = level;
- wret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
- if (wret < 0) {
- ret = wret;
- goto out;
- }
- node = path->nodes[level];
- btrfs_node_key(node, &found_key, path->slots[level]);
- WARN_ON(memcmp(&found_key, &root_item->drop_progress,
- sizeof(found_key)));
- /*
- * unlock our path, this is safe because only this
- * function is allowed to delete this snapshot
- */
- for (i = 0; i < BTRFS_MAX_LEVEL; i++) {
- if (path->nodes[i] && path->locks[i]) {
- path->locks[i] = 0;
- btrfs_tree_unlock(path->nodes[i]);
- }
- }
- }
- while(1) {
- atomic_inc(&root->fs_info->throttle_gen);
- wret = walk_down_tree(trans, root, path, &level);
- if (wret > 0)
- break;
- if (wret < 0)
- ret = wret;
+ level = btrfs_header_level(buf);
+ if (level == 0) {
+ struct btrfs_leaf_ref *ref;
+ struct btrfs_leaf_ref *orig_ref;
- wret = walk_up_tree(trans, root, path, &level);
- if (wret > 0)
- break;
- if (wret < 0)
- ret = wret;
- if (trans->transaction->in_commit) {
- ret = -EAGAIN;
- break;
+ orig_ref = btrfs_lookup_leaf_ref(root, orig_start);
+ if (!orig_ref)
+ return -ENOENT;
+
+ ref = btrfs_alloc_leaf_ref(root, orig_ref->nritems);
+ if (!ref) {
+ btrfs_free_leaf_ref(root, orig_ref);
+ return -ENOMEM;
}
- wake_up(&root->fs_info->transaction_throttle);
+
+ ref->nritems = orig_ref->nritems;
+ memcpy(ref->extents, orig_ref->extents,
+ sizeof(ref->extents[0]) * ref->nritems);
+
+ btrfs_free_leaf_ref(root, orig_ref);
+
+ ref->root_gen = trans->transid;
+ ref->bytenr = buf->start;
+ ref->owner = btrfs_header_owner(buf);
+ ref->generation = btrfs_header_generation(buf);
+
+ ret = btrfs_add_leaf_ref(root, ref, 0);
+ WARN_ON(ret);
+ btrfs_free_leaf_ref(root, ref);
}
- for (i = 0; i <= orig_level; i++) {
- if (path->nodes[i]) {
- free_extent_buffer(path->nodes[i]);
- path->nodes[i] = NULL;
+ return 0;
+}
+
+static noinline int invalidate_extent_cache(struct btrfs_root *root,
+ struct extent_buffer *leaf,
+ struct btrfs_block_group_cache *group,
+ struct btrfs_root *target_root)
+{
+ struct btrfs_key key;
+ struct inode *inode = NULL;
+ struct btrfs_file_extent_item *fi;
+ u64 num_bytes;
+ u64 skip_objectid = 0;
+ u32 nritems;
+ u32 i;
+
+ nritems = btrfs_header_nritems(leaf);
+ for (i = 0; i < nritems; i++) {
+ btrfs_item_key_to_cpu(leaf, &key, i);
+ if (key.objectid == skip_objectid ||
+ key.type != BTRFS_EXTENT_DATA_KEY)
+ continue;
+ fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
+ if (btrfs_file_extent_type(leaf, fi) ==
+ BTRFS_FILE_EXTENT_INLINE)
+ continue;
+ if (btrfs_file_extent_disk_bytenr(leaf, fi) == 0)
+ continue;
+ if (!inode || inode->i_ino != key.objectid) {
+ iput(inode);
+ inode = btrfs_ilookup(target_root->fs_info->sb,
+ key.objectid, target_root, 1);
+ }
+ if (!inode) {
+ skip_objectid = key.objectid;
+ continue;
}
+ num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
+
+ lock_extent(&BTRFS_I(inode)->io_tree, key.offset,
+ key.offset + num_bytes - 1, GFP_NOFS);
+ btrfs_drop_extent_cache(inode, key.offset,
+ key.offset + num_bytes - 1, 1);
+ unlock_extent(&BTRFS_I(inode)->io_tree, key.offset,
+ key.offset + num_bytes - 1, GFP_NOFS);
+ cond_resched();
}
-out:
- btrfs_free_path(path);
- return ret;
+ iput(inode);
+ return 0;
}
-int btrfs_free_block_groups(struct btrfs_fs_info *info)
+static noinline int replace_extents_in_leaf(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct extent_buffer *leaf,
+ struct btrfs_block_group_cache *group,
+ struct inode *reloc_inode)
{
- u64 start;
- u64 end;
- u64 ptr;
+ struct btrfs_key key;
+ struct btrfs_key extent_key;
+ struct btrfs_file_extent_item *fi;
+ struct btrfs_leaf_ref *ref;
+ struct disk_extent *new_extent;
+ u64 bytenr;
+ u64 num_bytes;
+ u32 nritems;
+ u32 i;
+ int ext_index;
+ int nr_extent;
int ret;
- mutex_lock(&info->alloc_mutex);
- while(1) {
- ret = find_first_extent_bit(&info->block_group_cache, 0,
- &start, &end, (unsigned int)-1);
- if (ret)
- break;
- ret = get_state_private(&info->block_group_cache, start, &ptr);
- if (!ret)
- kfree((void *)(unsigned long)ptr);
- clear_extent_bits(&info->block_group_cache, start,
- end, (unsigned int)-1, GFP_NOFS);
- }
- while(1) {
- ret = find_first_extent_bit(&info->free_space_cache, 0,
- &start, &end, EXTENT_DIRTY);
- if (ret)
- break;
- clear_extent_dirty(&info->free_space_cache, start,
- end, GFP_NOFS);
+ new_extent = kmalloc(sizeof(*new_extent), GFP_NOFS);
+ BUG_ON(!new_extent);
+
+ ref = btrfs_lookup_leaf_ref(root, leaf->start);
+ BUG_ON(!ref);
+
+ ext_index = -1;
+ nritems = btrfs_header_nritems(leaf);
+ for (i = 0; i < nritems; i++) {
+ btrfs_item_key_to_cpu(leaf, &key, i);
+ if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
+ continue;
+ fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
+ if (btrfs_file_extent_type(leaf, fi) ==
+ BTRFS_FILE_EXTENT_INLINE)
+ continue;
+ bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
+ num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi);
+ if (bytenr == 0)
+ continue;
+
+ ext_index++;
+ if (bytenr >= group->key.objectid + group->key.offset ||
+ bytenr + num_bytes <= group->key.objectid)
+ continue;
+
+ extent_key.objectid = bytenr;
+ extent_key.offset = num_bytes;
+ extent_key.type = BTRFS_EXTENT_ITEM_KEY;
+ nr_extent = 1;
+ ret = get_new_locations(reloc_inode, &extent_key,
+ group->key.objectid, 1,
+ &new_extent, &nr_extent);
+ if (ret > 0)
+ continue;
+ BUG_ON(ret < 0);
+
+ BUG_ON(ref->extents[ext_index].bytenr != bytenr);
+ BUG_ON(ref->extents[ext_index].num_bytes != num_bytes);
+ ref->extents[ext_index].bytenr = new_extent->disk_bytenr;
+ ref->extents[ext_index].num_bytes = new_extent->disk_num_bytes;
+
+ btrfs_set_file_extent_disk_bytenr(leaf, fi,
+ new_extent->disk_bytenr);
+ btrfs_set_file_extent_disk_num_bytes(leaf, fi,
+ new_extent->disk_num_bytes);
+ btrfs_mark_buffer_dirty(leaf);
+
+ ret = btrfs_inc_extent_ref(trans, root,
+ new_extent->disk_bytenr,
+ new_extent->disk_num_bytes,
+ leaf->start,
+ root->root_key.objectid,
+ trans->transid, key.objectid);
+ BUG_ON(ret);
+ ret = btrfs_free_extent(trans, root,
+ bytenr, num_bytes, leaf->start,
+ btrfs_header_owner(leaf),
+ btrfs_header_generation(leaf),
+ key.objectid, 0);
+ BUG_ON(ret);
+ cond_resched();
}
- mutex_unlock(&info->alloc_mutex);
+ kfree(new_extent);
+ BUG_ON(ext_index + 1 != ref->nritems);
+ btrfs_free_leaf_ref(root, ref);
return 0;
}
-static unsigned long calc_ra(unsigned long start, unsigned long last,
- unsigned long nr)
+int btrfs_free_reloc_root(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root)
{
- return min(last, start + nr - 1);
+ struct btrfs_root *reloc_root;
+ int ret;
+
+ if (root->reloc_root) {
+ reloc_root = root->reloc_root;
+ root->reloc_root = NULL;
+ list_add(&reloc_root->dead_list,
+ &root->fs_info->dead_reloc_roots);
+
+ btrfs_set_root_bytenr(&reloc_root->root_item,
+ reloc_root->node->start);
+ btrfs_set_root_level(&root->root_item,
+ btrfs_header_level(reloc_root->node));
+ memset(&reloc_root->root_item.drop_progress, 0,
+ sizeof(struct btrfs_disk_key));
+ reloc_root->root_item.drop_level = 0;
+
+ ret = btrfs_update_root(trans, root->fs_info->tree_root,
+ &reloc_root->root_key,
+ &reloc_root->root_item);
+ BUG_ON(ret);
+ }
+ return 0;
}
-static int noinline relocate_inode_pages(struct inode *inode, u64 start,
- u64 len)
+int btrfs_drop_dead_reloc_roots(struct btrfs_root *root)
{
- u64 page_start;
- u64 page_end;
- unsigned long last_index;
- unsigned long i;
- struct page *page;
- struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
- struct file_ra_state *ra;
- unsigned long total_read = 0;
- unsigned long ra_pages;
- struct btrfs_ordered_extent *ordered;
struct btrfs_trans_handle *trans;
+ struct btrfs_root *reloc_root;
+ struct btrfs_root *prev_root = NULL;
+ struct list_head dead_roots;
+ int ret;
+ unsigned long nr;
- ra = kzalloc(sizeof(*ra), GFP_NOFS);
+ INIT_LIST_HEAD(&dead_roots);
+ list_splice_init(&root->fs_info->dead_reloc_roots, &dead_roots);
- mutex_lock(&inode->i_mutex);
- i = start >> PAGE_CACHE_SHIFT;
- last_index = (start + len - 1) >> PAGE_CACHE_SHIFT;
+ while (!list_empty(&dead_roots)) {
+ reloc_root = list_entry(dead_roots.prev,
+ struct btrfs_root, dead_list);
+ list_del_init(&reloc_root->dead_list);
- ra_pages = BTRFS_I(inode)->root->fs_info->bdi.ra_pages;
+ BUG_ON(reloc_root->commit_root != NULL);
+ while (1) {
+ trans = btrfs_join_transaction(root, 1);
+ BUG_ON(!trans);
- file_ra_state_init(ra, inode->i_mapping);
+ mutex_lock(&root->fs_info->drop_mutex);
+ ret = btrfs_drop_snapshot(trans, reloc_root);
+ if (ret != -EAGAIN)
+ break;
+ mutex_unlock(&root->fs_info->drop_mutex);
- for (; i <= last_index; i++) {
- if (total_read % ra_pages == 0) {
- btrfs_force_ra(inode->i_mapping, ra, NULL, i,
- calc_ra(i, last_index, ra_pages));
- }
- total_read++;
-again:
- if (((u64)i << PAGE_CACHE_SHIFT) > i_size_read(inode))
- goto truncate_racing;
- page = grab_cache_page(inode->i_mapping, i);
- if (!page) {
- goto out_unlock;
- }
- if (!PageUptodate(page)) {
- btrfs_readpage(NULL, page);
- lock_page(page);
- if (!PageUptodate(page)) {
- unlock_page(page);
- page_cache_release(page);
- goto out_unlock;
- }
+ nr = trans->blocks_used;
+ ret = btrfs_end_transaction(trans, root);
+ BUG_ON(ret);
+ btrfs_btree_balance_dirty(root, nr);
}
- wait_on_page_writeback(page);
-
- page_start = (u64)page->index << PAGE_CACHE_SHIFT;
- page_end = page_start + PAGE_CACHE_SIZE - 1;
- lock_extent(io_tree, page_start, page_end, GFP_NOFS);
- ordered = btrfs_lookup_ordered_extent(inode, page_start);
- if (ordered) {
- unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
- unlock_page(page);
- page_cache_release(page);
- btrfs_start_ordered_extent(inode, ordered, 1);
- btrfs_put_ordered_extent(ordered);
- goto again;
- }
- set_page_extent_mapped(page);
+ free_extent_buffer(reloc_root->node);
+ ret = btrfs_del_root(trans, root->fs_info->tree_root,
+ &reloc_root->root_key);
+ BUG_ON(ret);
+ mutex_unlock(&root->fs_info->drop_mutex);
- set_extent_delalloc(io_tree, page_start,
- page_end, GFP_NOFS);
- set_page_dirty(page);
+ nr = trans->blocks_used;
+ ret = btrfs_end_transaction(trans, root);
+ BUG_ON(ret);
+ btrfs_btree_balance_dirty(root, nr);
- unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
- unlock_page(page);
- page_cache_release(page);
+ kfree(prev_root);
+ prev_root = reloc_root;
}
-
-out_unlock:
- /* we have to start the IO in order to get the ordered extents
- * instantiated. This allows the relocation to code to wait
- * for all the ordered extents to hit the disk.
- *
- * Otherwise, it would constantly loop over the same extents
- * because the old ones don't get deleted until the IO is
- * started
- */
- btrfs_fdatawrite_range(inode->i_mapping, start, start + len - 1,
- WB_SYNC_NONE);
- kfree(ra);
- trans = btrfs_start_transaction(BTRFS_I(inode)->root, 1);
- if (trans) {
- btrfs_end_transaction(trans, BTRFS_I(inode)->root);
- mark_inode_dirty(inode);
+ if (prev_root) {
+ btrfs_remove_leaf_refs(prev_root, (u64)-1, 0);
+ kfree(prev_root);
}
- mutex_unlock(&inode->i_mutex);
return 0;
+}
-truncate_racing:
- vmtruncate(inode, inode->i_size);
- balance_dirty_pages_ratelimited_nr(inode->i_mapping,
- total_read);
- goto out_unlock;
+int btrfs_add_dead_reloc_root(struct btrfs_root *root)
+{
+ list_add(&root->dead_list, &root->fs_info->dead_reloc_roots);
+ return 0;
}
-/*
- * The back references tell us which tree holds a ref on a block,
- * but it is possible for the tree root field in the reference to
- * reflect the original root before a snapshot was made. In this
- * case we should search through all the children of a given root
- * to find potential holders of references on a block.
- *
- * Instead, we do something a little less fancy and just search
- * all the roots for a given key/block combination.
- */
-static int find_root_for_ref(struct btrfs_root *root,
- struct btrfs_path *path,
- struct btrfs_key *key0,
- int level,
- int file_key,
- struct btrfs_root **found_root,
- u64 bytenr)
-{
- struct btrfs_key root_location;
- struct btrfs_root *cur_root = *found_root;
- struct btrfs_file_extent_item *file_extent;
- u64 root_search_start = BTRFS_FS_TREE_OBJECTID;
- u64 found_bytenr;
+int btrfs_cleanup_reloc_trees(struct btrfs_root *root)
+{
+ struct btrfs_root *reloc_root;
+ struct btrfs_trans_handle *trans;
+ struct btrfs_key location;
+ int found;
int ret;
- root_location.offset = (u64)-1;
- root_location.type = BTRFS_ROOT_ITEM_KEY;
- path->lowest_level = level;
- path->reada = 0;
- while(1) {
- ret = btrfs_search_slot(NULL, cur_root, key0, path, 0, 0);
- found_bytenr = 0;
- if (ret == 0 && file_key) {
- struct extent_buffer *leaf = path->nodes[0];
- file_extent = btrfs_item_ptr(leaf, path->slots[0],
- struct btrfs_file_extent_item);
- if (btrfs_file_extent_type(leaf, file_extent) ==
- BTRFS_FILE_EXTENT_REG) {
- found_bytenr =
- btrfs_file_extent_disk_bytenr(leaf,
- file_extent);
- }
- } else if (!file_key) {
- if (path->nodes[level])
- found_bytenr = path->nodes[level]->start;
- }
-
- btrfs_release_path(cur_root, path);
-
- if (found_bytenr == bytenr) {
- *found_root = cur_root;
- ret = 0;
- goto out;
- }
- ret = btrfs_search_root(root->fs_info->tree_root,
- root_search_start, &root_search_start);
- if (ret)
- break;
+ mutex_lock(&root->fs_info->tree_reloc_mutex);
+ ret = btrfs_find_dead_roots(root, BTRFS_TREE_RELOC_OBJECTID, NULL);
+ BUG_ON(ret);
+ found = !list_empty(&root->fs_info->dead_reloc_roots);
+ mutex_unlock(&root->fs_info->tree_reloc_mutex);
- root_location.objectid = root_search_start;
- cur_root = btrfs_read_fs_root_no_name(root->fs_info,
- &root_location);
- if (!cur_root) {
- ret = 1;
- break;
- }
+ if (found) {
+ trans = btrfs_start_transaction(root, 1);
+ BUG_ON(!trans);
+ ret = btrfs_commit_transaction(trans, root);
+ BUG_ON(ret);
}
-out:
- path->lowest_level = 0;
- return ret;
+
+ location.objectid = BTRFS_DATA_RELOC_TREE_OBJECTID;
+ location.offset = (u64)-1;
+ location.type = BTRFS_ROOT_ITEM_KEY;
+
+ reloc_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
+ BUG_ON(!reloc_root);
+ btrfs_orphan_cleanup(reloc_root);
+ return 0;
}
-/*
- * note, this releases the path
- */
-static int noinline relocate_one_reference(struct btrfs_root *extent_root,
- struct btrfs_path *path,
- struct btrfs_key *extent_key,
- u64 *last_file_objectid,
- u64 *last_file_offset,
- u64 *last_file_root,
- u64 last_extent)
-{
- struct inode *inode;
- struct btrfs_root *found_root;
- struct btrfs_key root_location;
- struct btrfs_key found_key;
- struct btrfs_extent_ref *ref;
- u64 ref_root;
- u64 ref_gen;
- u64 ref_objectid;
- u64 ref_offset;
+static noinline int init_reloc_tree(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root)
+{
+ struct btrfs_root *reloc_root;
+ struct extent_buffer *eb;
+ struct btrfs_root_item *root_item;
+ struct btrfs_key root_key;
int ret;
- int level;
- WARN_ON(!mutex_is_locked(&extent_root->fs_info->alloc_mutex));
+ BUG_ON(!root->ref_cows);
+ if (root->reloc_root)
+ return 0;
- ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
- struct btrfs_extent_ref);
- ref_root = btrfs_ref_root(path->nodes[0], ref);
- ref_gen = btrfs_ref_generation(path->nodes[0], ref);
- ref_objectid = btrfs_ref_objectid(path->nodes[0], ref);
- ref_offset = btrfs_ref_offset(path->nodes[0], ref);
- btrfs_release_path(extent_root, path);
+ root_item = kmalloc(sizeof(*root_item), GFP_NOFS);
+ BUG_ON(!root_item);
- root_location.objectid = ref_root;
- if (ref_gen == 0)
- root_location.offset = 0;
- else
- root_location.offset = (u64)-1;
- root_location.type = BTRFS_ROOT_ITEM_KEY;
-
- found_root = btrfs_read_fs_root_no_name(extent_root->fs_info,
- &root_location);
- BUG_ON(!found_root);
- mutex_unlock(&extent_root->fs_info->alloc_mutex);
-
- if (ref_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
- found_key.objectid = ref_objectid;
- found_key.type = BTRFS_EXTENT_DATA_KEY;
- found_key.offset = ref_offset;
- level = 0;
-
- if (last_extent == extent_key->objectid &&
- *last_file_objectid == ref_objectid &&
- *last_file_offset == ref_offset &&
- *last_file_root == ref_root)
- goto out;
+ ret = btrfs_copy_root(trans, root, root->commit_root,
+ &eb, BTRFS_TREE_RELOC_OBJECTID);
+ BUG_ON(ret);
- ret = find_root_for_ref(extent_root, path, &found_key,
- level, 1, &found_root,
- extent_key->objectid);
+ root_key.objectid = BTRFS_TREE_RELOC_OBJECTID;
+ root_key.offset = root->root_key.objectid;
+ root_key.type = BTRFS_ROOT_ITEM_KEY;
- if (ret)
- goto out;
+ memcpy(root_item, &root->root_item, sizeof(root_item));
+ btrfs_set_root_refs(root_item, 0);
+ btrfs_set_root_bytenr(root_item, eb->start);
+ btrfs_set_root_level(root_item, btrfs_header_level(eb));
+ btrfs_set_root_generation(root_item, trans->transid);
- if (last_extent == extent_key->objectid &&
- *last_file_objectid == ref_objectid &&
- *last_file_offset == ref_offset &&
- *last_file_root == ref_root)
- goto out;
+ btrfs_tree_unlock(eb);
+ free_extent_buffer(eb);
- inode = btrfs_iget_locked(extent_root->fs_info->sb,
- ref_objectid, found_root);
- if (inode->i_state & I_NEW) {
- /* the inode and parent dir are two different roots */
- BTRFS_I(inode)->root = found_root;
- BTRFS_I(inode)->location.objectid = ref_objectid;
- BTRFS_I(inode)->location.type = BTRFS_INODE_ITEM_KEY;
- BTRFS_I(inode)->location.offset = 0;
- btrfs_read_locked_inode(inode);
- unlock_new_inode(inode);
+ ret = btrfs_insert_root(trans, root->fs_info->tree_root,
+ &root_key, root_item);
+ BUG_ON(ret);
+ kfree(root_item);
- }
- /* this can happen if the reference is not against
- * the latest version of the tree root
- */
- if (is_bad_inode(inode))
- goto out;
+ reloc_root = btrfs_read_fs_root_no_radix(root->fs_info->tree_root,
+ &root_key);
+ BUG_ON(!reloc_root);
+ reloc_root->last_trans = trans->transid;
+ reloc_root->commit_root = NULL;
+ reloc_root->ref_tree = &root->fs_info->reloc_ref_tree;
- *last_file_objectid = inode->i_ino;
- *last_file_root = found_root->root_key.objectid;
- *last_file_offset = ref_offset;
+ root->reloc_root = reloc_root;
+ return 0;
+}
- relocate_inode_pages(inode, ref_offset, extent_key->offset);
- iput(inode);
- } else {
- struct btrfs_trans_handle *trans;
- struct extent_buffer *eb;
- int needs_lock = 0;
+/*
+ * Core function of space balance.
+ *
+ * The idea is using reloc trees to relocate tree blocks in reference
+ * counted roots. There is one reloc tree for each subvol, and all
+ * reloc trees share same root key objectid. Reloc trees are snapshots
+ * of the latest committed roots of subvols (root->commit_root).
+ *
+ * To relocate a tree block referenced by a subvol, there are two steps.
+ * COW the block through subvol's reloc tree, then update block pointer
+ * in the subvol to point to the new block. Since all reloc trees share
+ * same root key objectid, doing special handing for tree blocks owned
+ * by them is easy. Once a tree block has been COWed in one reloc tree,
+ * we can use the resulting new block directly when the same block is
+ * required to COW again through other reloc trees. By this way, relocated
+ * tree blocks are shared between reloc trees, so they are also shared
+ * between subvols.
+ */
+static noinline int relocate_one_path(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path,
+ struct btrfs_key *first_key,
+ struct btrfs_ref_path *ref_path,
+ struct btrfs_block_group_cache *group,
+ struct inode *reloc_inode)
+{
+ struct btrfs_root *reloc_root;
+ struct extent_buffer *eb = NULL;
+ struct btrfs_key *keys;
+ u64 *nodes;
+ int level;
+ int shared_level;
+ int lowest_level = 0;
+ int ret;
- eb = read_tree_block(found_root, extent_key->objectid,
- extent_key->offset, 0);
- btrfs_tree_lock(eb);
- level = btrfs_header_level(eb);
+ if (ref_path->owner_objectid < BTRFS_FIRST_FREE_OBJECTID)
+ lowest_level = ref_path->owner_objectid;
- if (level == 0)
- btrfs_item_key_to_cpu(eb, &found_key, 0);
- else
- btrfs_node_key_to_cpu(eb, &found_key, 0);
+ if (!root->ref_cows) {
+ path->lowest_level = lowest_level;
+ ret = btrfs_search_slot(trans, root, first_key, path, 0, 1);
+ BUG_ON(ret < 0);
+ path->lowest_level = 0;
+ btrfs_release_path(root, path);
+ return 0;
+ }
- btrfs_tree_unlock(eb);
- free_extent_buffer(eb);
+ mutex_lock(&root->fs_info->tree_reloc_mutex);
+ ret = init_reloc_tree(trans, root);
+ BUG_ON(ret);
+ reloc_root = root->reloc_root;
- ret = find_root_for_ref(extent_root, path, &found_key,
- level, 0, &found_root,
- extent_key->objectid);
+ shared_level = ref_path->shared_level;
+ ref_path->shared_level = BTRFS_MAX_LEVEL - 1;
- if (ret)
- goto out;
+ keys = ref_path->node_keys;
+ nodes = ref_path->new_nodes;
+ memset(&keys[shared_level + 1], 0,
+ sizeof(*keys) * (BTRFS_MAX_LEVEL - shared_level - 1));
+ memset(&nodes[shared_level + 1], 0,
+ sizeof(*nodes) * (BTRFS_MAX_LEVEL - shared_level - 1));
- /*
- * right here almost anything could happen to our key,
- * but that's ok. The cow below will either relocate it
- * or someone else will have relocated it. Either way,
- * it is in a different spot than it was before and
- * we're happy.
- */
+ if (nodes[lowest_level] == 0) {
+ path->lowest_level = lowest_level;
+ ret = btrfs_search_slot(trans, reloc_root, first_key, path,
+ 0, 1);
+ BUG_ON(ret);
+ for (level = lowest_level; level < BTRFS_MAX_LEVEL; level++) {
+ eb = path->nodes[level];
+ if (!eb || eb == reloc_root->node)
+ break;
+ nodes[level] = eb->start;
+ if (level == 0)
+ btrfs_item_key_to_cpu(eb, &keys[level], 0);
+ else
+ btrfs_node_key_to_cpu(eb, &keys[level], 0);
+ }
+ if (nodes[0] &&
+ ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
+ eb = path->nodes[0];
+ ret = replace_extents_in_leaf(trans, reloc_root, eb,
+ group, reloc_inode);
+ BUG_ON(ret);
+ }
+ btrfs_release_path(reloc_root, path);
+ } else {
+ ret = btrfs_merge_path(trans, reloc_root, keys, nodes,
+ lowest_level);
+ BUG_ON(ret);
+ }
- trans = btrfs_start_transaction(found_root, 1);
+ /*
+ * replace tree blocks in the fs tree with tree blocks in
+ * the reloc tree.
+ */
+ ret = btrfs_merge_path(trans, root, keys, nodes, lowest_level);
+ BUG_ON(ret < 0);
- if (found_root == extent_root->fs_info->extent_root ||
- found_root == extent_root->fs_info->chunk_root ||
- found_root == extent_root->fs_info->dev_root) {
- needs_lock = 1;
- mutex_lock(&extent_root->fs_info->alloc_mutex);
- }
+ if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
+ ret = btrfs_search_slot(trans, reloc_root, first_key, path,
+ 0, 0);
+ BUG_ON(ret);
+ extent_buffer_get(path->nodes[0]);
+ eb = path->nodes[0];
+ btrfs_release_path(reloc_root, path);
+ ret = invalidate_extent_cache(reloc_root, eb, group, root);
+ BUG_ON(ret);
+ free_extent_buffer(eb);
+ }
- path->lowest_level = level;
- path->reada = 2;
- ret = btrfs_search_slot(trans, found_root, &found_key, path,
- 0, 1);
- path->lowest_level = 0;
- btrfs_release_path(found_root, path);
+ mutex_unlock(&root->fs_info->tree_reloc_mutex);
+ path->lowest_level = 0;
+ return 0;
+}
- if (found_root == found_root->fs_info->extent_root)
- btrfs_extent_post_op(trans, found_root);
- if (needs_lock)
- mutex_unlock(&extent_root->fs_info->alloc_mutex);
+static noinline int relocate_tree_block(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path,
+ struct btrfs_key *first_key,
+ struct btrfs_ref_path *ref_path)
+{
+ int ret;
- btrfs_end_transaction(trans, found_root);
+ ret = relocate_one_path(trans, root, path, first_key,
+ ref_path, NULL, NULL);
+ BUG_ON(ret);
+
+ if (root == root->fs_info->extent_root)
+ btrfs_extent_post_op(trans, root);
- }
-out:
- mutex_lock(&extent_root->fs_info->alloc_mutex);
return 0;
}
-static int noinline del_extent_zero(struct btrfs_root *extent_root,
+static noinline int del_extent_zero(struct btrfs_trans_handle *trans,
+ struct btrfs_root *extent_root,
struct btrfs_path *path,
struct btrfs_key *extent_key)
{
int ret;
- struct btrfs_trans_handle *trans;
- trans = btrfs_start_transaction(extent_root, 1);
ret = btrfs_search_slot(trans, extent_root, extent_key, path, -1, 1);
- if (ret > 0) {
- ret = -EIO;
- goto out;
- }
- if (ret < 0)
+ if (ret)
goto out;
ret = btrfs_del_item(trans, extent_root, path);
out:
- btrfs_end_transaction(trans, extent_root);
+ btrfs_release_path(extent_root, path);
return ret;
}
-static int noinline relocate_one_extent(struct btrfs_root *extent_root,
+static noinline struct btrfs_root *read_ref_root(struct btrfs_fs_info *fs_info,
+ struct btrfs_ref_path *ref_path)
+{
+ struct btrfs_key root_key;
+
+ root_key.objectid = ref_path->root_objectid;
+ root_key.type = BTRFS_ROOT_ITEM_KEY;
+ if (is_cowonly_root(ref_path->root_objectid))
+ root_key.offset = 0;
+ else
+ root_key.offset = (u64)-1;
+
+ return btrfs_read_fs_root_no_name(fs_info, &root_key);
+}
+
+static noinline int relocate_one_extent(struct btrfs_root *extent_root,
struct btrfs_path *path,
- struct btrfs_key *extent_key)
+ struct btrfs_key *extent_key,
+ struct btrfs_block_group_cache *group,
+ struct inode *reloc_inode, int pass)
{
- struct btrfs_key key;
- struct btrfs_key found_key;
- struct extent_buffer *leaf;
- u64 last_file_objectid = 0;
- u64 last_file_root = 0;
- u64 last_file_offset = (u64)-1;
- u64 last_extent = 0;
- u32 nritems;
- u32 item_size;
- int ret = 0;
+ struct btrfs_trans_handle *trans;
+ struct btrfs_root *found_root;
+ struct btrfs_ref_path *ref_path = NULL;
+ struct disk_extent *new_extents = NULL;
+ int nr_extents = 0;
+ int loops;
+ int ret;
+ int level;
+ struct btrfs_key first_key;
+ u64 prev_block = 0;
+
+
+ trans = btrfs_start_transaction(extent_root, 1);
+ BUG_ON(!trans);
if (extent_key->objectid == 0) {
- ret = del_extent_zero(extent_root, path, extent_key);
+ ret = del_extent_zero(trans, extent_root, path, extent_key);
goto out;
}
- key.objectid = extent_key->objectid;
- key.type = BTRFS_EXTENT_REF_KEY;
- key.offset = 0;
- while(1) {
- ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
+ ref_path = kmalloc(sizeof(*ref_path), GFP_NOFS);
+ if (!ref_path) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ for (loops = 0; ; loops++) {
+ if (loops == 0) {
+ ret = btrfs_first_ref_path(trans, extent_root, ref_path,
+ extent_key->objectid);
+ } else {
+ ret = btrfs_next_ref_path(trans, extent_root, ref_path);
+ }
if (ret < 0)
goto out;
+ if (ret > 0)
+ break;
- ret = 0;
- leaf = path->nodes[0];
- nritems = btrfs_header_nritems(leaf);
- if (path->slots[0] == nritems) {
- ret = btrfs_next_leaf(extent_root, path);
- if (ret > 0) {
- ret = 0;
- goto out;
+ if (ref_path->root_objectid == BTRFS_TREE_LOG_OBJECTID ||
+ ref_path->root_objectid == BTRFS_TREE_RELOC_OBJECTID)
+ continue;
+
+ found_root = read_ref_root(extent_root->fs_info, ref_path);
+ BUG_ON(!found_root);
+ /*
+ * for reference counted tree, only process reference paths
+ * rooted at the latest committed root.
+ */
+ if (found_root->ref_cows &&
+ ref_path->root_generation != found_root->root_key.offset)
+ continue;
+
+ if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
+ if (pass == 0) {
+ /*
+ * copy data extents to new locations
+ */
+ u64 group_start = group->key.objectid;
+ ret = relocate_data_extent(reloc_inode,
+ extent_key,
+ group_start);
+ if (ret < 0)
+ goto out;
+ break;
}
- if (ret < 0)
- goto out;
- leaf = path->nodes[0];
+ level = 0;
+ } else {
+ level = ref_path->owner_objectid;
}
- btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
- if (found_key.objectid != extent_key->objectid) {
- break;
- }
+ if (prev_block != ref_path->nodes[level]) {
+ struct extent_buffer *eb;
+ u64 block_start = ref_path->nodes[level];
+ u64 block_size = btrfs_level_size(found_root, level);
- if (found_key.type != BTRFS_EXTENT_REF_KEY) {
- break;
- }
+ eb = read_tree_block(found_root, block_start,
+ block_size, 0);
+ btrfs_tree_lock(eb);
+ BUG_ON(level != btrfs_header_level(eb));
- key.offset = found_key.offset + 1;
- item_size = btrfs_item_size_nr(leaf, path->slots[0]);
+ if (level == 0)
+ btrfs_item_key_to_cpu(eb, &first_key, 0);
+ else
+ btrfs_node_key_to_cpu(eb, &first_key, 0);
- ret = relocate_one_reference(extent_root, path, extent_key,
- &last_file_objectid,
- &last_file_offset,
- &last_file_root, last_extent);
- if (ret)
+ btrfs_tree_unlock(eb);
+ free_extent_buffer(eb);
+ prev_block = block_start;
+ }
+
+ mutex_lock(&extent_root->fs_info->trans_mutex);
+ btrfs_record_root_in_trans(found_root);
+ mutex_unlock(&extent_root->fs_info->trans_mutex);
+ if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
+ /*
+ * try to update data extent references while
+ * keeping metadata shared between snapshots.
+ */
+ if (pass == 1) {
+ ret = relocate_one_path(trans, found_root,
+ path, &first_key, ref_path,
+ group, reloc_inode);
+ if (ret < 0)
+ goto out;
+ continue;
+ }
+ /*
+ * use fallback method to process the remaining
+ * references.
+ */
+ if (!new_extents) {
+ u64 group_start = group->key.objectid;
+ new_extents = kmalloc(sizeof(*new_extents),
+ GFP_NOFS);
+ nr_extents = 1;
+ ret = get_new_locations(reloc_inode,
+ extent_key,
+ group_start, 1,
+ &new_extents,
+ &nr_extents);
+ if (ret)
+ goto out;
+ }
+ ret = replace_one_extent(trans, found_root,
+ path, extent_key,
+ &first_key, ref_path,
+ new_extents, nr_extents);
+ } else {
+ ret = relocate_tree_block(trans, found_root, path,
+ &first_key, ref_path);
+ }
+ if (ret < 0)
goto out;
- last_extent = extent_key->objectid;
}
ret = 0;
out:
- btrfs_release_path(extent_root, path);
+ btrfs_end_transaction(trans, extent_root);
+ kfree(new_extents);
+ kfree(ref_path);
return ret;
}
u64 stripped = BTRFS_BLOCK_GROUP_RAID0 |
BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10;
- num_devices = root->fs_info->fs_devices->num_devices;
+ num_devices = root->fs_info->fs_devices->rw_devices;
if (num_devices == 1) {
stripped |= BTRFS_BLOCK_GROUP_DUP;
stripped = flags & ~stripped;
return flags;
}
-int __alloc_chunk_for_shrink(struct btrfs_root *root,
+static int __alloc_chunk_for_shrink(struct btrfs_root *root,
struct btrfs_block_group_cache *shrink_block_group,
int force)
{
spin_lock(&shrink_block_group->lock);
if (btrfs_block_group_used(&shrink_block_group->item) > 0) {
spin_unlock(&shrink_block_group->lock);
- mutex_unlock(&root->fs_info->alloc_mutex);
trans = btrfs_start_transaction(root, 1);
- mutex_lock(&root->fs_info->alloc_mutex);
spin_lock(&shrink_block_group->lock);
new_alloc_flags = update_block_group_flags(root,
do_chunk_alloc(trans, root->fs_info->extent_root,
calc + 2 * 1024 * 1024, new_alloc_flags, force);
- mutex_unlock(&root->fs_info->alloc_mutex);
btrfs_end_transaction(trans, root);
- mutex_lock(&root->fs_info->alloc_mutex);
} else
spin_unlock(&shrink_block_group->lock);
return 0;
}
-int btrfs_shrink_extent_tree(struct btrfs_root *root, u64 shrink_start)
+static int __insert_orphan_inode(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ u64 objectid, u64 size)
+{
+ struct btrfs_path *path;
+ struct btrfs_inode_item *item;
+ struct extent_buffer *leaf;
+ int ret;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ ret = btrfs_insert_empty_inode(trans, root, path, objectid);
+ if (ret)
+ goto out;
+
+ leaf = path->nodes[0];
+ item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_inode_item);
+ memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item));
+ btrfs_set_inode_generation(leaf, item, 1);
+ btrfs_set_inode_size(leaf, item, size);
+ btrfs_set_inode_mode(leaf, item, S_IFREG | 0600);
+ btrfs_set_inode_flags(leaf, item, BTRFS_INODE_NOCOMPRESS);
+ btrfs_mark_buffer_dirty(leaf);
+ btrfs_release_path(root, path);
+out:
+ btrfs_free_path(path);
+ return ret;
+}
+
+static noinline struct inode *create_reloc_inode(struct btrfs_fs_info *fs_info,
+ struct btrfs_block_group_cache *group)
+{
+ struct inode *inode = NULL;
+ struct btrfs_trans_handle *trans;
+ struct btrfs_root *root;
+ struct btrfs_key root_key;
+ u64 objectid = BTRFS_FIRST_FREE_OBJECTID;
+ int err = 0;
+
+ root_key.objectid = BTRFS_DATA_RELOC_TREE_OBJECTID;
+ root_key.type = BTRFS_ROOT_ITEM_KEY;
+ root_key.offset = (u64)-1;
+ root = btrfs_read_fs_root_no_name(fs_info, &root_key);
+ if (IS_ERR(root))
+ return ERR_CAST(root);
+
+ trans = btrfs_start_transaction(root, 1);
+ BUG_ON(!trans);
+
+ err = btrfs_find_free_objectid(trans, root, objectid, &objectid);
+ if (err)
+ goto out;
+
+ err = __insert_orphan_inode(trans, root, objectid, group->key.offset);
+ BUG_ON(err);
+
+ err = btrfs_insert_file_extent(trans, root, objectid, 0, 0, 0,
+ group->key.offset, 0, group->key.offset,
+ 0, 0, 0);
+ BUG_ON(err);
+
+ inode = btrfs_iget_locked(root->fs_info->sb, objectid, root);
+ if (inode->i_state & I_NEW) {
+ BTRFS_I(inode)->root = root;
+ BTRFS_I(inode)->location.objectid = objectid;
+ BTRFS_I(inode)->location.type = BTRFS_INODE_ITEM_KEY;
+ BTRFS_I(inode)->location.offset = 0;
+ btrfs_read_locked_inode(inode);
+ unlock_new_inode(inode);
+ BUG_ON(is_bad_inode(inode));
+ } else {
+ BUG_ON(1);
+ }
+ BTRFS_I(inode)->index_cnt = group->key.objectid;
+
+ err = btrfs_orphan_add(trans, inode);
+out:
+ btrfs_end_transaction(trans, root);
+ if (err) {
+ if (inode)
+ iput(inode);
+ inode = ERR_PTR(err);
+ }
+ return inode;
+}
+
+int btrfs_reloc_clone_csums(struct inode *inode, u64 file_pos, u64 len)
+{
+
+ struct btrfs_ordered_sum *sums;
+ struct btrfs_sector_sum *sector_sum;
+ struct btrfs_ordered_extent *ordered;
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct list_head list;
+ size_t offset;
+ int ret;
+ u64 disk_bytenr;
+
+ INIT_LIST_HEAD(&list);
+
+ ordered = btrfs_lookup_ordered_extent(inode, file_pos);
+ BUG_ON(ordered->file_offset != file_pos || ordered->len != len);
+
+ disk_bytenr = file_pos + BTRFS_I(inode)->index_cnt;
+ ret = btrfs_lookup_csums_range(root->fs_info->csum_root, disk_bytenr,
+ disk_bytenr + len - 1, &list);
+
+ while (!list_empty(&list)) {
+ sums = list_entry(list.next, struct btrfs_ordered_sum, list);
+ list_del_init(&sums->list);
+
+ sector_sum = sums->sums;
+ sums->bytenr = ordered->start;
+
+ offset = 0;
+ while (offset < sums->len) {
+ sector_sum->bytenr += ordered->start - disk_bytenr;
+ sector_sum++;
+ offset += root->sectorsize;
+ }
+
+ btrfs_add_ordered_sum(inode, ordered, sums);
+ }
+ btrfs_put_ordered_extent(ordered);
+ return 0;
+}
+
+int btrfs_relocate_block_group(struct btrfs_root *root, u64 group_start)
{
struct btrfs_trans_handle *trans;
- struct btrfs_root *tree_root = root->fs_info->tree_root;
struct btrfs_path *path;
- u64 cur_byte;
- u64 total_found;
- u64 shrink_last_byte;
- struct btrfs_block_group_cache *shrink_block_group;
struct btrfs_fs_info *info = root->fs_info;
- struct btrfs_key key;
- struct btrfs_key found_key;
struct extent_buffer *leaf;
+ struct inode *reloc_inode;
+ struct btrfs_block_group_cache *block_group;
+ struct btrfs_key key;
+ u64 skipped;
+ u64 cur_byte;
+ u64 total_found;
u32 nritems;
int ret;
int progress;
+ int pass = 0;
+
+ root = root->fs_info->extent_root;
- mutex_lock(&root->fs_info->alloc_mutex);
- shrink_block_group = btrfs_lookup_block_group(root->fs_info,
- shrink_start);
- BUG_ON(!shrink_block_group);
+ block_group = btrfs_lookup_block_group(info, group_start);
+ BUG_ON(!block_group);
- shrink_last_byte = shrink_block_group->key.objectid +
- shrink_block_group->key.offset;
+ printk(KERN_INFO "btrfs relocating block group %llu flags %llu\n",
+ (unsigned long long)block_group->key.objectid,
+ (unsigned long long)block_group->flags);
- shrink_block_group->space_info->total_bytes -=
- shrink_block_group->key.offset;
path = btrfs_alloc_path();
- root = root->fs_info->extent_root;
- path->reada = 2;
+ BUG_ON(!path);
- printk("btrfs relocating block group %llu flags %llu\n",
- (unsigned long long)shrink_start,
- (unsigned long long)shrink_block_group->flags);
+ reloc_inode = create_reloc_inode(info, block_group);
+ BUG_ON(IS_ERR(reloc_inode));
- __alloc_chunk_for_shrink(root, shrink_block_group, 1);
+ __alloc_chunk_for_shrink(root, block_group, 1);
+ set_block_group_readonly(block_group);
+ btrfs_start_delalloc_inodes(info->tree_root);
+ btrfs_wait_ordered_extents(info->tree_root, 0);
again:
-
- shrink_block_group->ro = 1;
-
+ skipped = 0;
total_found = 0;
progress = 0;
- key.objectid = shrink_start;
+ key.objectid = block_group->key.objectid;
key.offset = 0;
key.type = 0;
cur_byte = key.objectid;
- ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
- if (ret < 0)
- goto out;
-
- ret = btrfs_previous_item(root, path, 0, BTRFS_EXTENT_ITEM_KEY);
- if (ret < 0)
- goto out;
+ trans = btrfs_start_transaction(info->tree_root, 1);
+ btrfs_commit_transaction(trans, info->tree_root);
- if (ret == 0) {
- leaf = path->nodes[0];
- btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
- if (found_key.objectid + found_key.offset > shrink_start &&
- found_key.objectid < shrink_last_byte) {
- cur_byte = found_key.objectid;
- key.objectid = cur_byte;
- }
- }
- btrfs_release_path(root, path);
+ mutex_lock(&root->fs_info->cleaner_mutex);
+ btrfs_clean_old_snapshots(info->tree_root);
+ btrfs_remove_leaf_refs(info->tree_root, (u64)-1, 1);
+ mutex_unlock(&root->fs_info->cleaner_mutex);
- while(1) {
+ while (1) {
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
if (ret < 0)
goto out;
-
next:
leaf = path->nodes[0];
nritems = btrfs_header_nritems(leaf);
nritems = btrfs_header_nritems(leaf);
}
- btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
+ btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
- if (found_key.objectid >= shrink_last_byte)
+ if (key.objectid >= block_group->key.objectid +
+ block_group->key.offset)
break;
if (progress && need_resched()) {
- memcpy(&key, &found_key, sizeof(key));
- cond_resched();
btrfs_release_path(root, path);
- btrfs_search_slot(NULL, root, &key, path, 0, 0);
+ cond_resched();
progress = 0;
- goto next;
+ continue;
}
progress = 1;
- if (btrfs_key_type(&found_key) != BTRFS_EXTENT_ITEM_KEY ||
- found_key.objectid + found_key.offset <= cur_byte) {
- memcpy(&key, &found_key, sizeof(key));
- key.offset++;
+ if (btrfs_key_type(&key) != BTRFS_EXTENT_ITEM_KEY ||
+ key.objectid + key.offset <= cur_byte) {
path->slots[0]++;
goto next;
}
total_found++;
- cur_byte = found_key.objectid + found_key.offset;
- key.objectid = cur_byte;
+ cur_byte = key.objectid + key.offset;
btrfs_release_path(root, path);
- ret = relocate_one_extent(root, path, &found_key);
- __alloc_chunk_for_shrink(root, shrink_block_group, 0);
- }
-
- btrfs_release_path(root, path);
- if (total_found > 0) {
- printk("btrfs relocate found %llu last extent was %llu\n",
- (unsigned long long)total_found,
- (unsigned long long)found_key.objectid);
- mutex_unlock(&root->fs_info->alloc_mutex);
- trans = btrfs_start_transaction(tree_root, 1);
- btrfs_commit_transaction(trans, tree_root);
-
- btrfs_clean_old_snapshots(tree_root);
-
- btrfs_wait_ordered_extents(tree_root);
+ __alloc_chunk_for_shrink(root, block_group, 0);
+ ret = relocate_one_extent(root, path, &key, block_group,
+ reloc_inode, pass);
+ BUG_ON(ret < 0);
+ if (ret > 0)
+ skipped++;
- trans = btrfs_start_transaction(tree_root, 1);
- btrfs_commit_transaction(trans, tree_root);
- mutex_lock(&root->fs_info->alloc_mutex);
- goto again;
+ key.objectid = cur_byte;
+ key.type = 0;
+ key.offset = 0;
}
- /*
- * we've freed all the extents, now remove the block
- * group item from the tree
- */
- mutex_unlock(&root->fs_info->alloc_mutex);
-
- trans = btrfs_start_transaction(root, 1);
-
- mutex_lock(&root->fs_info->alloc_mutex);
- memcpy(&key, &shrink_block_group->key, sizeof(key));
+ btrfs_release_path(root, path);
- ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
- if (ret > 0)
- ret = -EIO;
- if (ret < 0) {
- btrfs_end_transaction(trans, root);
- goto out;
+ if (pass == 0) {
+ btrfs_wait_ordered_range(reloc_inode, 0, (u64)-1);
+ invalidate_mapping_pages(reloc_inode->i_mapping, 0, -1);
}
- clear_extent_bits(&info->block_group_cache, key.objectid,
- key.objectid + key.offset - 1,
- (unsigned int)-1, GFP_NOFS);
-
-
- clear_extent_bits(&info->free_space_cache,
- key.objectid, key.objectid + key.offset - 1,
- (unsigned int)-1, GFP_NOFS);
-
- memset(shrink_block_group, 0, sizeof(*shrink_block_group));
- kfree(shrink_block_group);
+ if (total_found > 0) {
+ printk(KERN_INFO "btrfs found %llu extents in pass %d\n",
+ (unsigned long long)total_found, pass);
+ pass++;
+ if (total_found == skipped && pass > 2) {
+ iput(reloc_inode);
+ reloc_inode = create_reloc_inode(info, block_group);
+ pass = 0;
+ }
+ goto again;
+ }
- btrfs_del_item(trans, root, path);
- btrfs_release_path(root, path);
- mutex_unlock(&root->fs_info->alloc_mutex);
- btrfs_commit_transaction(trans, root);
+ /* delete reloc_inode */
+ iput(reloc_inode);
- mutex_lock(&root->fs_info->alloc_mutex);
+ /* unpin extents in this range */
+ trans = btrfs_start_transaction(info->tree_root, 1);
+ btrfs_commit_transaction(trans, info->tree_root);
- /* the code to unpin extents might set a few bits in the free
- * space cache for this range again
- */
- clear_extent_bits(&info->free_space_cache,
- key.objectid, key.objectid + key.offset - 1,
- (unsigned int)-1, GFP_NOFS);
+ spin_lock(&block_group->lock);
+ WARN_ON(block_group->pinned > 0);
+ WARN_ON(block_group->reserved > 0);
+ WARN_ON(btrfs_block_group_used(&block_group->item) > 0);
+ spin_unlock(&block_group->lock);
+ put_block_group(block_group);
+ ret = 0;
out:
btrfs_free_path(path);
- mutex_unlock(&root->fs_info->alloc_mutex);
return ret;
}
-int find_first_block_group(struct btrfs_root *root, struct btrfs_path *path,
- struct btrfs_key *key)
+static int find_first_block_group(struct btrfs_root *root,
+ struct btrfs_path *path, struct btrfs_key *key)
{
int ret = 0;
struct btrfs_key found_key;
if (ret < 0)
goto out;
- while(1) {
+ while (1) {
slot = path->slots[0];
leaf = path->nodes[0];
if (slot >= btrfs_header_nritems(leaf)) {
return ret;
}
+int btrfs_free_block_groups(struct btrfs_fs_info *info)
+{
+ struct btrfs_block_group_cache *block_group;
+ struct rb_node *n;
+
+ spin_lock(&info->block_group_cache_lock);
+ while ((n = rb_last(&info->block_group_cache_tree)) != NULL) {
+ block_group = rb_entry(n, struct btrfs_block_group_cache,
+ cache_node);
+ rb_erase(&block_group->cache_node,
+ &info->block_group_cache_tree);
+ spin_unlock(&info->block_group_cache_lock);
+
+ btrfs_remove_free_space_cache(block_group);
+ down_write(&block_group->space_info->groups_sem);
+ list_del(&block_group->list);
+ up_write(&block_group->space_info->groups_sem);
+
+ WARN_ON(atomic_read(&block_group->count) != 1);
+ kfree(block_group);
+
+ spin_lock(&info->block_group_cache_lock);
+ }
+ spin_unlock(&info->block_group_cache_lock);
+ return 0;
+}
+
int btrfs_read_block_groups(struct btrfs_root *root)
{
struct btrfs_path *path;
int ret;
- int bit;
struct btrfs_block_group_cache *cache;
struct btrfs_fs_info *info = root->fs_info;
struct btrfs_space_info *space_info;
- struct extent_io_tree *block_group_cache;
struct btrfs_key key;
struct btrfs_key found_key;
struct extent_buffer *leaf;
- block_group_cache = &info->block_group_cache;
root = info->extent_root;
key.objectid = 0;
key.offset = 0;
if (!path)
return -ENOMEM;
- mutex_lock(&root->fs_info->alloc_mutex);
- while(1) {
+ while (1) {
ret = find_first_block_group(root, path, &key);
if (ret > 0) {
ret = 0;
break;
}
+ atomic_set(&cache->count, 1);
spin_lock_init(&cache->lock);
+ mutex_init(&cache->alloc_mutex);
+ mutex_init(&cache->cache_mutex);
+ INIT_LIST_HEAD(&cache->list);
read_extent_buffer(leaf, &cache->item,
btrfs_item_ptr_offset(leaf, path->slots[0]),
sizeof(cache->item));
key.objectid = found_key.objectid + found_key.offset;
btrfs_release_path(root, path);
cache->flags = btrfs_block_group_flags(&cache->item);
- bit = 0;
- if (cache->flags & BTRFS_BLOCK_GROUP_DATA) {
- bit = BLOCK_GROUP_DATA;
- } else if (cache->flags & BTRFS_BLOCK_GROUP_SYSTEM) {
- bit = BLOCK_GROUP_SYSTEM;
- } else if (cache->flags & BTRFS_BLOCK_GROUP_METADATA) {
- bit = BLOCK_GROUP_METADATA;
- }
- set_avail_alloc_bits(info, cache->flags);
ret = update_space_info(info, cache->flags, found_key.offset,
btrfs_block_group_used(&cache->item),
&space_info);
BUG_ON(ret);
cache->space_info = space_info;
+ down_write(&space_info->groups_sem);
+ list_add_tail(&cache->list, &space_info->block_groups);
+ up_write(&space_info->groups_sem);
- /* use EXTENT_LOCKED to prevent merging */
- set_extent_bits(block_group_cache, found_key.objectid,
- found_key.objectid + found_key.offset - 1,
- EXTENT_LOCKED, GFP_NOFS);
- set_state_private(block_group_cache, found_key.objectid,
- (unsigned long)cache);
- set_extent_bits(block_group_cache, found_key.objectid,
- found_key.objectid + found_key.offset - 1,
- bit | EXTENT_LOCKED, GFP_NOFS);
- if (key.objectid >=
- btrfs_super_total_bytes(&info->super_copy))
- break;
+ ret = btrfs_add_block_group_cache(root->fs_info, cache);
+ BUG_ON(ret);
+
+ set_avail_alloc_bits(root->fs_info, cache->flags);
+ if (btrfs_chunk_readonly(root, cache->key.objectid))
+ set_block_group_readonly(cache);
}
ret = 0;
error:
btrfs_free_path(path);
- mutex_unlock(&root->fs_info->alloc_mutex);
return ret;
}
u64 size)
{
int ret;
- int bit = 0;
struct btrfs_root *extent_root;
struct btrfs_block_group_cache *cache;
- struct extent_io_tree *block_group_cache;
- WARN_ON(!mutex_is_locked(&root->fs_info->alloc_mutex));
extent_root = root->fs_info->extent_root;
- block_group_cache = &root->fs_info->block_group_cache;
+
+ root->fs_info->last_trans_new_blockgroup = trans->transid;
cache = kzalloc(sizeof(*cache), GFP_NOFS);
- BUG_ON(!cache);
+ if (!cache)
+ return -ENOMEM;
+
cache->key.objectid = chunk_offset;
cache->key.offset = size;
+ cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
+ atomic_set(&cache->count, 1);
spin_lock_init(&cache->lock);
- btrfs_set_key_type(&cache->key, BTRFS_BLOCK_GROUP_ITEM_KEY);
+ mutex_init(&cache->alloc_mutex);
+ mutex_init(&cache->cache_mutex);
+ INIT_LIST_HEAD(&cache->list);
btrfs_set_block_group_used(&cache->item, bytes_used);
btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid);
ret = update_space_info(root->fs_info, cache->flags, size, bytes_used,
&cache->space_info);
BUG_ON(ret);
+ down_write(&cache->space_info->groups_sem);
+ list_add_tail(&cache->list, &cache->space_info->block_groups);
+ up_write(&cache->space_info->groups_sem);
- bit = block_group_state_bits(type);
- set_extent_bits(block_group_cache, chunk_offset,
- chunk_offset + size - 1,
- EXTENT_LOCKED, GFP_NOFS);
- set_state_private(block_group_cache, chunk_offset,
- (unsigned long)cache);
- set_extent_bits(block_group_cache, chunk_offset,
- chunk_offset + size - 1,
- bit | EXTENT_LOCKED, GFP_NOFS);
+ ret = btrfs_add_block_group_cache(root->fs_info, cache);
+ BUG_ON(ret);
ret = btrfs_insert_item(trans, extent_root, &cache->key, &cache->item,
sizeof(cache->item));
BUG_ON(ret);
- finish_current_insert(trans, extent_root);
- ret = del_pending_extents(trans, extent_root);
+ finish_current_insert(trans, extent_root, 0);
+ ret = del_pending_extents(trans, extent_root, 0);
BUG_ON(ret);
set_avail_alloc_bits(extent_root->fs_info, type);
return 0;
}
+
+int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, u64 group_start)
+{
+ struct btrfs_path *path;
+ struct btrfs_block_group_cache *block_group;
+ struct btrfs_key key;
+ int ret;
+
+ root = root->fs_info->extent_root;
+
+ block_group = btrfs_lookup_block_group(root->fs_info, group_start);
+ BUG_ON(!block_group);
+ BUG_ON(!block_group->ro);
+
+ memcpy(&key, &block_group->key, sizeof(key));
+
+ path = btrfs_alloc_path();
+ BUG_ON(!path);
+
+ spin_lock(&root->fs_info->block_group_cache_lock);
+ rb_erase(&block_group->cache_node,
+ &root->fs_info->block_group_cache_tree);
+ spin_unlock(&root->fs_info->block_group_cache_lock);
+ btrfs_remove_free_space_cache(block_group);
+ down_write(&block_group->space_info->groups_sem);
+ list_del(&block_group->list);
+ up_write(&block_group->space_info->groups_sem);
+
+ spin_lock(&block_group->space_info->lock);
+ block_group->space_info->total_bytes -= block_group->key.offset;
+ block_group->space_info->bytes_readonly -= block_group->key.offset;
+ spin_unlock(&block_group->space_info->lock);
+ block_group->space_info->full = 0;
+
+ put_block_group(block_group);
+ put_block_group(block_group);
+
+ ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
+ if (ret > 0)
+ ret = -EIO;
+ if (ret < 0)
+ goto out;
+
+ ret = btrfs_del_item(trans, root, path);
+out:
+ btrfs_free_path(path);
+ return ret;
+}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff