*/
#include <linux/fs.h>
+#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/writeback.h>
#include <linux/pagemap.h>
+#include <linux/blkdev.h>
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
#include "locking.h"
-#include "ref-cache.h"
-
-static int total_trans = 0;
-extern struct kmem_cache *btrfs_trans_handle_cachep;
-extern struct kmem_cache *btrfs_transaction_cachep;
+#include "tree-log.h"
#define BTRFS_ROOT_TRANS_TAG 0
-struct dirty_root {
- struct list_head list;
- struct btrfs_root *root;
- struct btrfs_root *latest_root;
- struct btrfs_leaf_ref_tree ref_tree;
-};
-
static noinline void put_transaction(struct btrfs_transaction *transaction)
{
WARN_ON(transaction->use_count == 0);
transaction->use_count--;
if (transaction->use_count == 0) {
- WARN_ON(total_trans == 0);
- total_trans--;
list_del_init(&transaction->list);
memset(transaction, 0, sizeof(*transaction));
kmem_cache_free(btrfs_transaction_cachep, transaction);
}
}
+static noinline void switch_commit_root(struct btrfs_root *root)
+{
+ free_extent_buffer(root->commit_root);
+ root->commit_root = btrfs_root_node(root);
+}
+
+/*
+ * either allocate a new transaction or hop into the existing one
+ */
static noinline int join_transaction(struct btrfs_root *root)
{
struct btrfs_transaction *cur_trans;
if (!cur_trans) {
cur_trans = kmem_cache_alloc(btrfs_transaction_cachep,
GFP_NOFS);
- total_trans++;
BUG_ON(!cur_trans);
root->fs_info->generation++;
- root->fs_info->last_alloc = 0;
- root->fs_info->last_data_alloc = 0;
cur_trans->num_writers = 1;
cur_trans->num_joined = 0;
cur_trans->transid = root->fs_info->generation;
cur_trans->use_count = 1;
cur_trans->commit_done = 0;
cur_trans->start_time = get_seconds();
+
+ cur_trans->delayed_refs.root = RB_ROOT;
+ cur_trans->delayed_refs.num_entries = 0;
+ cur_trans->delayed_refs.num_heads_ready = 0;
+ cur_trans->delayed_refs.num_heads = 0;
+ cur_trans->delayed_refs.flushing = 0;
+ cur_trans->delayed_refs.run_delayed_start = 0;
+ spin_lock_init(&cur_trans->delayed_refs.lock);
+
INIT_LIST_HEAD(&cur_trans->pending_snapshots);
list_add_tail(&cur_trans->list, &root->fs_info->trans_list);
extent_io_tree_init(&cur_trans->dirty_pages,
return 0;
}
-static noinline int record_root_in_trans(struct btrfs_root *root)
+/*
+ * this does all the record keeping required to make sure that a reference
+ * counted root is properly recorded in a given transaction. This is required
+ * to make sure the old root from before we joined the transaction is deleted
+ * when the transaction commits
+ */
+static noinline int record_root_in_trans(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root)
{
- struct dirty_root *dirty;
- u64 running_trans_id = root->fs_info->running_transaction->transid;
- if (root->ref_cows && root->last_trans < running_trans_id) {
+ if (root->ref_cows && root->last_trans < trans->transid) {
WARN_ON(root == root->fs_info->extent_root);
- if (root->root_item.refs != 0) {
- radix_tree_tag_set(&root->fs_info->fs_roots_radix,
- (unsigned long)root->root_key.objectid,
- BTRFS_ROOT_TRANS_TAG);
-
- dirty = kmalloc(sizeof(*dirty), GFP_NOFS);
- BUG_ON(!dirty);
- dirty->root = kmalloc(sizeof(*dirty->root), GFP_NOFS);
- BUG_ON(!dirty->root);
-
- dirty->latest_root = root;
- INIT_LIST_HEAD(&dirty->list);
- btrfs_leaf_ref_tree_init(&dirty->ref_tree);
- dirty->ref_tree.generation = running_trans_id;
-
- root->commit_root = btrfs_root_node(root);
- root->ref_tree = &dirty->ref_tree;
-
- memcpy(dirty->root, root, sizeof(*root));
- spin_lock_init(&dirty->root->node_lock);
- mutex_init(&dirty->root->objectid_mutex);
- dirty->root->node = root->commit_root;
- dirty->root->commit_root = NULL;
- } else {
- WARN_ON(1);
- }
- root->last_trans = running_trans_id;
+ WARN_ON(root->commit_root != root->node);
+
+ radix_tree_tag_set(&root->fs_info->fs_roots_radix,
+ (unsigned long)root->root_key.objectid,
+ BTRFS_ROOT_TRANS_TAG);
+ root->last_trans = trans->transid;
+ btrfs_init_reloc_root(trans, root);
}
return 0;
}
-struct btrfs_trans_handle *start_transaction(struct btrfs_root *root,
- int num_blocks, int join)
+int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root)
{
- struct btrfs_trans_handle *h =
- kmem_cache_alloc(btrfs_trans_handle_cachep, GFP_NOFS);
- struct btrfs_transaction *cur_trans;
- int ret;
+ if (!root->ref_cows)
+ return 0;
mutex_lock(&root->fs_info->trans_mutex);
+ if (root->last_trans == trans->transid) {
+ mutex_unlock(&root->fs_info->trans_mutex);
+ return 0;
+ }
+
+ record_root_in_trans(trans, root);
+ mutex_unlock(&root->fs_info->trans_mutex);
+ return 0;
+}
+
+/* wait for commit against the current transaction to become unblocked
+ * when this is done, it is safe to start a new transaction, but the current
+ * transaction might not be fully on disk.
+ */
+static void wait_current_trans(struct btrfs_root *root)
+{
+ struct btrfs_transaction *cur_trans;
+
cur_trans = root->fs_info->running_transaction;
- if (cur_trans && cur_trans->blocked && !join) {
+ if (cur_trans && cur_trans->blocked) {
DEFINE_WAIT(wait);
cur_trans->use_count++;
- while(1) {
+ while (1) {
prepare_to_wait(&root->fs_info->transaction_wait, &wait,
TASK_UNINTERRUPTIBLE);
- if (cur_trans->blocked) {
- mutex_unlock(&root->fs_info->trans_mutex);
- schedule();
- mutex_lock(&root->fs_info->trans_mutex);
- finish_wait(&root->fs_info->transaction_wait,
- &wait);
- } else {
- finish_wait(&root->fs_info->transaction_wait,
- &wait);
+ if (!cur_trans->blocked)
break;
- }
+ mutex_unlock(&root->fs_info->trans_mutex);
+ schedule();
+ mutex_lock(&root->fs_info->trans_mutex);
}
+ finish_wait(&root->fs_info->transaction_wait, &wait);
put_transaction(cur_trans);
}
+}
+
+enum btrfs_trans_type {
+ TRANS_START,
+ TRANS_JOIN,
+ TRANS_USERSPACE,
+};
+
+static int may_wait_transaction(struct btrfs_root *root, int type)
+{
+ if (!root->fs_info->log_root_recovering &&
+ ((type == TRANS_START && !root->fs_info->open_ioctl_trans) ||
+ type == TRANS_USERSPACE))
+ return 1;
+ return 0;
+}
+
+static struct btrfs_trans_handle *start_transaction(struct btrfs_root *root,
+ u64 num_items, int type)
+{
+ struct btrfs_trans_handle *h;
+ struct btrfs_transaction *cur_trans;
+ int retries = 0;
+ int ret;
+again:
+ h = kmem_cache_alloc(btrfs_trans_handle_cachep, GFP_NOFS);
+ if (!h)
+ return ERR_PTR(-ENOMEM);
+
+ mutex_lock(&root->fs_info->trans_mutex);
+ if (may_wait_transaction(root, type))
+ wait_current_trans(root);
+
ret = join_transaction(root);
BUG_ON(ret);
- record_root_in_trans(root);
- h->transid = root->fs_info->running_transaction->transid;
- h->transaction = root->fs_info->running_transaction;
- h->blocks_reserved = num_blocks;
+ cur_trans = root->fs_info->running_transaction;
+ cur_trans->use_count++;
+ mutex_unlock(&root->fs_info->trans_mutex);
+
+ h->transid = cur_trans->transid;
+ h->transaction = cur_trans;
h->blocks_used = 0;
- h->block_group = NULL;
- h->alloc_exclude_nr = 0;
- h->alloc_exclude_start = 0;
- root->fs_info->running_transaction->use_count++;
+ h->block_group = 0;
+ h->bytes_reserved = 0;
+ h->delayed_ref_updates = 0;
+ h->block_rsv = NULL;
+
+ smp_mb();
+ if (cur_trans->blocked && may_wait_transaction(root, type)) {
+ btrfs_commit_transaction(h, root);
+ goto again;
+ }
+
+ if (num_items > 0) {
+ ret = btrfs_trans_reserve_metadata(h, root, num_items,
+ &retries);
+ if (ret == -EAGAIN) {
+ btrfs_commit_transaction(h, root);
+ goto again;
+ }
+ if (ret < 0) {
+ btrfs_end_transaction(h, root);
+ return ERR_PTR(ret);
+ }
+ }
+
+ mutex_lock(&root->fs_info->trans_mutex);
+ record_root_in_trans(h, root);
mutex_unlock(&root->fs_info->trans_mutex);
+
+ if (!current->journal_info && type != TRANS_USERSPACE)
+ current->journal_info = h;
return h;
}
struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root,
- int num_blocks)
+ int num_items)
{
- return start_transaction(root, num_blocks, 0);
+ return start_transaction(root, num_items, TRANS_START);
}
struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root,
int num_blocks)
{
- return start_transaction(root, num_blocks, 1);
+ return start_transaction(root, 0, TRANS_JOIN);
+}
+
+struct btrfs_trans_handle *btrfs_start_ioctl_transaction(struct btrfs_root *r,
+ int num_blocks)
+{
+ return start_transaction(r, 0, TRANS_USERSPACE);
}
+/* wait for a transaction commit to be fully complete */
static noinline int wait_for_commit(struct btrfs_root *root,
struct btrfs_transaction *commit)
{
DEFINE_WAIT(wait);
mutex_lock(&root->fs_info->trans_mutex);
- while(!commit->commit_done) {
+ while (!commit->commit_done) {
prepare_to_wait(&commit->commit_wait, &wait,
TASK_UNINTERRUPTIBLE);
if (commit->commit_done)
return 0;
}
+#if 0
+/*
+ * rate limit against the drop_snapshot code. This helps to slow down new
+ * operations if the drop_snapshot code isn't able to keep up.
+ */
+static void throttle_on_drops(struct btrfs_root *root)
+{
+ struct btrfs_fs_info *info = root->fs_info;
+ int harder_count = 0;
+
+harder:
+ if (atomic_read(&info->throttles)) {
+ DEFINE_WAIT(wait);
+ int thr;
+ thr = atomic_read(&info->throttle_gen);
+
+ do {
+ prepare_to_wait(&info->transaction_throttle,
+ &wait, TASK_UNINTERRUPTIBLE);
+ if (!atomic_read(&info->throttles)) {
+ finish_wait(&info->transaction_throttle, &wait);
+ break;
+ }
+ schedule();
+ finish_wait(&info->transaction_throttle, &wait);
+ } while (thr == atomic_read(&info->throttle_gen));
+ harder_count++;
+
+ if (root->fs_info->total_ref_cache_size > 1 * 1024 * 1024 &&
+ harder_count < 2)
+ goto harder;
+
+ if (root->fs_info->total_ref_cache_size > 5 * 1024 * 1024 &&
+ harder_count < 10)
+ goto harder;
+
+ if (root->fs_info->total_ref_cache_size > 10 * 1024 * 1024 &&
+ harder_count < 20)
+ goto harder;
+ }
+}
+#endif
+
+void btrfs_throttle(struct btrfs_root *root)
+{
+ mutex_lock(&root->fs_info->trans_mutex);
+ if (!root->fs_info->open_ioctl_trans)
+ wait_current_trans(root);
+ mutex_unlock(&root->fs_info->trans_mutex);
+}
+
+static int should_end_transaction(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root)
+{
+ int ret;
+ ret = btrfs_block_rsv_check(trans, root,
+ &root->fs_info->global_block_rsv, 0, 5);
+ return ret ? 1 : 0;
+}
+
+int btrfs_should_end_transaction(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root)
+{
+ struct btrfs_transaction *cur_trans = trans->transaction;
+ int updates;
+
+ if (cur_trans->blocked || cur_trans->delayed_refs.flushing)
+ return 1;
+
+ updates = trans->delayed_ref_updates;
+ trans->delayed_ref_updates = 0;
+ if (updates)
+ btrfs_run_delayed_refs(trans, root, updates);
+
+ return should_end_transaction(trans, root);
+}
+
static int __btrfs_end_transaction(struct btrfs_trans_handle *trans,
struct btrfs_root *root, int throttle)
{
- struct btrfs_transaction *cur_trans;
+ struct btrfs_transaction *cur_trans = trans->transaction;
+ struct btrfs_fs_info *info = root->fs_info;
+ int count = 0;
+
+ while (count < 4) {
+ unsigned long cur = trans->delayed_ref_updates;
+ trans->delayed_ref_updates = 0;
+ if (cur &&
+ trans->transaction->delayed_refs.num_heads_ready > 64) {
+ trans->delayed_ref_updates = 0;
+
+ /*
+ * do a full flush if the transaction is trying
+ * to close
+ */
+ if (trans->transaction->delayed_refs.flushing)
+ cur = 0;
+ btrfs_run_delayed_refs(trans, root, cur);
+ } else {
+ break;
+ }
+ count++;
+ }
- mutex_lock(&root->fs_info->trans_mutex);
- cur_trans = root->fs_info->running_transaction;
- WARN_ON(cur_trans != trans->transaction);
+ btrfs_trans_release_metadata(trans, root);
+
+ if (!root->fs_info->open_ioctl_trans &&
+ should_end_transaction(trans, root))
+ trans->transaction->blocked = 1;
+
+ if (cur_trans->blocked && !cur_trans->in_commit) {
+ if (throttle)
+ return btrfs_commit_transaction(trans, root);
+ else
+ wake_up_process(info->transaction_kthread);
+ }
+
+ mutex_lock(&info->trans_mutex);
+ WARN_ON(cur_trans != info->running_transaction);
WARN_ON(cur_trans->num_writers < 1);
cur_trans->num_writers--;
if (waitqueue_active(&cur_trans->writer_wait))
wake_up(&cur_trans->writer_wait);
-
- if (0 && cur_trans->in_commit && throttle) {
- DEFINE_WAIT(wait);
- mutex_unlock(&root->fs_info->trans_mutex);
- prepare_to_wait(&root->fs_info->transaction_throttle, &wait,
- TASK_UNINTERRUPTIBLE);
- schedule();
- finish_wait(&root->fs_info->transaction_throttle, &wait);
- mutex_lock(&root->fs_info->trans_mutex);
- }
-
put_transaction(cur_trans);
- mutex_unlock(&root->fs_info->trans_mutex);
+ mutex_unlock(&info->trans_mutex);
+
+ if (current->journal_info == trans)
+ current->journal_info = NULL;
memset(trans, 0, sizeof(*trans));
kmem_cache_free(btrfs_trans_handle_cachep, trans);
+
+ if (throttle)
+ btrfs_run_delayed_iputs(root);
+
return 0;
}
return __btrfs_end_transaction(trans, root, 1);
}
-
-int btrfs_write_and_wait_transaction(struct btrfs_trans_handle *trans,
- struct btrfs_root *root)
+/*
+ * when btree blocks are allocated, they have some corresponding bits set for
+ * them in one of two extent_io trees. This is used to make sure all of
+ * those extents are sent to disk but does not wait on them
+ */
+int btrfs_write_marked_extents(struct btrfs_root *root,
+ struct extent_io_tree *dirty_pages, int mark)
{
int ret;
- int err;
+ int err = 0;
int werr = 0;
- struct extent_io_tree *dirty_pages;
struct page *page;
struct inode *btree_inode = root->fs_info->btree_inode;
- u64 start;
+ u64 start = 0;
u64 end;
unsigned long index;
- if (!trans || !trans->transaction) {
- return filemap_write_and_wait(btree_inode->i_mapping);
- }
- dirty_pages = &trans->transaction->dirty_pages;
- while(1) {
- ret = find_first_extent_bit(dirty_pages, 0, &start, &end,
- EXTENT_DIRTY);
+ while (1) {
+ ret = find_first_extent_bit(dirty_pages, start, &start, &end,
+ mark);
if (ret)
break;
- clear_extent_dirty(dirty_pages, start, end, GFP_NOFS);
- while(start <= end) {
+ while (start <= end) {
+ cond_resched();
+
index = start >> PAGE_CACHE_SHIFT;
start = (u64)(index + 1) << PAGE_CACHE_SHIFT;
- page = find_lock_page(btree_inode->i_mapping, index);
+ page = find_get_page(btree_inode->i_mapping, index);
if (!page)
continue;
+
+ btree_lock_page_hook(page);
+ if (!page->mapping) {
+ unlock_page(page);
+ page_cache_release(page);
+ continue;
+ }
+
if (PageWriteback(page)) {
if (PageDirty(page))
wait_on_page_writeback(page);
page_cache_release(page);
}
}
- err = filemap_fdatawait(btree_inode->i_mapping);
if (err)
werr = err;
return werr;
}
+/*
+ * when btree blocks are allocated, they have some corresponding bits set for
+ * them in one of two extent_io trees. This is used to make sure all of
+ * those extents are on disk for transaction or log commit. We wait
+ * on all the pages and clear them from the dirty pages state tree
+ */
+int btrfs_wait_marked_extents(struct btrfs_root *root,
+ struct extent_io_tree *dirty_pages, int mark)
+{
+ int ret;
+ int err = 0;
+ int werr = 0;
+ struct page *page;
+ struct inode *btree_inode = root->fs_info->btree_inode;
+ u64 start = 0;
+ u64 end;
+ unsigned long index;
+
+ while (1) {
+ ret = find_first_extent_bit(dirty_pages, start, &start, &end,
+ mark);
+ if (ret)
+ break;
+
+ clear_extent_bits(dirty_pages, start, end, mark, GFP_NOFS);
+ while (start <= end) {
+ index = start >> PAGE_CACHE_SHIFT;
+ start = (u64)(index + 1) << PAGE_CACHE_SHIFT;
+ page = find_get_page(btree_inode->i_mapping, index);
+ if (!page)
+ continue;
+ if (PageDirty(page)) {
+ btree_lock_page_hook(page);
+ wait_on_page_writeback(page);
+ err = write_one_page(page, 0);
+ if (err)
+ werr = err;
+ }
+ wait_on_page_writeback(page);
+ page_cache_release(page);
+ cond_resched();
+ }
+ }
+ if (err)
+ werr = err;
+ return werr;
+}
+
+/*
+ * when btree blocks are allocated, they have some corresponding bits set for
+ * them in one of two extent_io trees. This is used to make sure all of
+ * those extents are on disk for transaction or log commit
+ */
+int btrfs_write_and_wait_marked_extents(struct btrfs_root *root,
+ struct extent_io_tree *dirty_pages, int mark)
+{
+ int ret;
+ int ret2;
+
+ ret = btrfs_write_marked_extents(root, dirty_pages, mark);
+ ret2 = btrfs_wait_marked_extents(root, dirty_pages, mark);
+ return ret || ret2;
+}
+
+int btrfs_write_and_wait_transaction(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root)
+{
+ if (!trans || !trans->transaction) {
+ struct inode *btree_inode;
+ btree_inode = root->fs_info->btree_inode;
+ return filemap_write_and_wait(btree_inode->i_mapping);
+ }
+ return btrfs_write_and_wait_marked_extents(root,
+ &trans->transaction->dirty_pages,
+ EXTENT_DIRTY);
+}
+
+/*
+ * this is used to update the root pointer in the tree of tree roots.
+ *
+ * But, in the case of the extent allocation tree, updating the root
+ * pointer may allocate blocks which may change the root of the extent
+ * allocation tree.
+ *
+ * So, this loops and repeats and makes sure the cowonly root didn't
+ * change while the root pointer was being updated in the metadata.
+ */
static int update_cowonly_root(struct btrfs_trans_handle *trans,
struct btrfs_root *root)
{
int ret;
u64 old_root_bytenr;
+ u64 old_root_used;
struct btrfs_root *tree_root = root->fs_info->tree_root;
+ old_root_used = btrfs_root_used(&root->root_item);
btrfs_write_dirty_block_groups(trans, root);
- while(1) {
+
+ while (1) {
old_root_bytenr = btrfs_root_bytenr(&root->root_item);
- if (old_root_bytenr == root->node->start)
+ if (old_root_bytenr == root->node->start &&
+ old_root_used == btrfs_root_used(&root->root_item))
break;
- btrfs_set_root_bytenr(&root->root_item,
- root->node->start);
- btrfs_set_root_level(&root->root_item,
- btrfs_header_level(root->node));
+
+ btrfs_set_root_node(&root->root_item, root->node);
ret = btrfs_update_root(trans, tree_root,
&root->root_key,
&root->root_item);
BUG_ON(ret);
- btrfs_write_dirty_block_groups(trans, root);
+
+ old_root_used = btrfs_root_used(&root->root_item);
+ ret = btrfs_write_dirty_block_groups(trans, root);
+ BUG_ON(ret);
}
+
+ if (root != root->fs_info->extent_root)
+ switch_commit_root(root);
+
return 0;
}
-int btrfs_commit_tree_roots(struct btrfs_trans_handle *trans,
- struct btrfs_root *root)
+/*
+ * update all the cowonly tree roots on disk
+ */
+static noinline int commit_cowonly_roots(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root)
{
struct btrfs_fs_info *fs_info = root->fs_info;
struct list_head *next;
+ struct extent_buffer *eb;
+ int ret;
- while(!list_empty(&fs_info->dirty_cowonly_roots)) {
+ ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1);
+ BUG_ON(ret);
+
+ eb = btrfs_lock_root_node(fs_info->tree_root);
+ btrfs_cow_block(trans, fs_info->tree_root, eb, NULL, 0, &eb);
+ btrfs_tree_unlock(eb);
+ free_extent_buffer(eb);
+
+ ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1);
+ BUG_ON(ret);
+
+ while (!list_empty(&fs_info->dirty_cowonly_roots)) {
next = fs_info->dirty_cowonly_roots.next;
list_del_init(next);
root = list_entry(next, struct btrfs_root, dirty_list);
+
update_cowonly_root(trans, root);
}
+
+ down_write(&fs_info->extent_commit_sem);
+ switch_commit_root(fs_info->extent_root);
+ up_write(&fs_info->extent_commit_sem);
+
return 0;
}
-int btrfs_add_dead_root(struct btrfs_root *root,
- struct btrfs_root *latest,
- struct list_head *dead_list)
+/*
+ * dead roots are old snapshots that need to be deleted. This allocates
+ * a dirty root struct and adds it into the list of dead roots that need to
+ * be deleted
+ */
+int btrfs_add_dead_root(struct btrfs_root *root)
{
- struct dirty_root *dirty;
-
- dirty = kmalloc(sizeof(*dirty), GFP_NOFS);
- if (!dirty)
- return -ENOMEM;
- btrfs_leaf_ref_tree_init(&dirty->ref_tree);
- dirty->root = root;
- dirty->latest_root = latest;
- root->ref_tree = NULL;
- list_add(&dirty->list, dead_list);
+ mutex_lock(&root->fs_info->trans_mutex);
+ list_add(&root->root_list, &root->fs_info->dead_roots);
+ mutex_unlock(&root->fs_info->trans_mutex);
return 0;
}
-static noinline int add_dirty_roots(struct btrfs_trans_handle *trans,
- struct radix_tree_root *radix,
- struct list_head *list)
+/*
+ * update all the cowonly tree roots on disk
+ */
+static noinline int commit_fs_roots(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root)
{
- struct dirty_root *dirty;
struct btrfs_root *gang[8];
- struct btrfs_root *root;
+ struct btrfs_fs_info *fs_info = root->fs_info;
int i;
int ret;
int err = 0;
- u32 refs;
- while(1) {
- ret = radix_tree_gang_lookup_tag(radix, (void **)gang, 0,
+ while (1) {
+ ret = radix_tree_gang_lookup_tag(&fs_info->fs_roots_radix,
+ (void **)gang, 0,
ARRAY_SIZE(gang),
BTRFS_ROOT_TRANS_TAG);
if (ret == 0)
break;
for (i = 0; i < ret; i++) {
root = gang[i];
- radix_tree_tag_clear(radix,
- (unsigned long)root->root_key.objectid,
- BTRFS_ROOT_TRANS_TAG);
-
- BUG_ON(!root->ref_tree);
- dirty = container_of(root->ref_tree, struct dirty_root,
- ref_tree);
-
- if (root->commit_root == root->node) {
- WARN_ON(root->node->start !=
- btrfs_root_bytenr(&root->root_item));
-
- BUG_ON(!btrfs_leaf_ref_tree_empty(
- root->ref_tree));
- free_extent_buffer(root->commit_root);
- root->commit_root = NULL;
- root->ref_tree = NULL;
-
- kfree(dirty->root);
- kfree(dirty);
-
- /* make sure to update the root on disk
- * so we get any updates to the block used
- * counts
- */
- err = btrfs_update_root(trans,
- root->fs_info->tree_root,
- &root->root_key,
- &root->root_item);
- continue;
+ radix_tree_tag_clear(&fs_info->fs_roots_radix,
+ (unsigned long)root->root_key.objectid,
+ BTRFS_ROOT_TRANS_TAG);
+
+ btrfs_free_log(trans, root);
+ btrfs_update_reloc_root(trans, root);
+ btrfs_orphan_commit_root(trans, root);
+
+ if (root->commit_root != root->node) {
+ switch_commit_root(root);
+ btrfs_set_root_node(&root->root_item,
+ root->node);
}
- memset(&root->root_item.drop_progress, 0,
- sizeof(struct btrfs_disk_key));
- root->root_item.drop_level = 0;
- root->commit_root = NULL;
- root->ref_tree = NULL;
- root->root_key.offset = root->fs_info->generation;
- btrfs_set_root_bytenr(&root->root_item,
- root->node->start);
- btrfs_set_root_level(&root->root_item,
- btrfs_header_level(root->node));
- err = btrfs_insert_root(trans, root->fs_info->tree_root,
+ err = btrfs_update_root(trans, fs_info->tree_root,
&root->root_key,
&root->root_item);
if (err)
break;
-
- refs = btrfs_root_refs(&dirty->root->root_item);
- btrfs_set_root_refs(&dirty->root->root_item, refs - 1);
- err = btrfs_update_root(trans, root->fs_info->tree_root,
- &dirty->root->root_key,
- &dirty->root->root_item);
-
- BUG_ON(err);
- if (refs == 1) {
- list_add(&dirty->list, list);
- } else {
- WARN_ON(1);
- free_extent_buffer(dirty->root->node);
- kfree(dirty->root);
- kfree(dirty);
- }
}
}
return err;
}
+/*
+ * defrag a given btree. If cacheonly == 1, this won't read from the disk,
+ * otherwise every leaf in the btree is read and defragged.
+ */
int btrfs_defrag_root(struct btrfs_root *root, int cacheonly)
{
struct btrfs_fs_info *info = root->fs_info;
- int ret;
struct btrfs_trans_handle *trans;
+ int ret;
unsigned long nr;
- smp_mb();
- if (root->defrag_running)
+ if (xchg(&root->defrag_running, 1))
return 0;
- trans = btrfs_start_transaction(root, 1);
+
while (1) {
- root->defrag_running = 1;
+ trans = btrfs_start_transaction(root, 0);
+ if (IS_ERR(trans))
+ return PTR_ERR(trans);
+
ret = btrfs_defrag_leaves(trans, root, cacheonly);
+
nr = trans->blocks_used;
btrfs_end_transaction(trans, root);
btrfs_btree_balance_dirty(info->tree_root, nr);
cond_resched();
- trans = btrfs_start_transaction(root, 1);
if (root->fs_info->closing || ret != -EAGAIN)
break;
}
root->defrag_running = 0;
- smp_mb();
- btrfs_end_transaction(trans, root);
- return 0;
+ return ret;
}
-static noinline int drop_dirty_roots(struct btrfs_root *tree_root,
- struct list_head *list)
+#if 0
+/*
+ * when dropping snapshots, we generate a ton of delayed refs, and it makes
+ * sense not to join the transaction while it is trying to flush the current
+ * queue of delayed refs out.
+ *
+ * This is used by the drop snapshot code only
+ */
+static noinline int wait_transaction_pre_flush(struct btrfs_fs_info *info)
{
- struct dirty_root *dirty;
- struct btrfs_trans_handle *trans;
- unsigned long nr;
- u64 num_bytes;
- u64 bytes_used;
- int ret = 0;
- int err;
-
- while(!list_empty(list)) {
- struct btrfs_root *root;
+ DEFINE_WAIT(wait);
- dirty = list_entry(list->next, struct dirty_root, list);
- list_del_init(&dirty->list);
+ mutex_lock(&info->trans_mutex);
+ while (info->running_transaction &&
+ info->running_transaction->delayed_refs.flushing) {
+ prepare_to_wait(&info->transaction_wait, &wait,
+ TASK_UNINTERRUPTIBLE);
+ mutex_unlock(&info->trans_mutex);
- num_bytes = btrfs_root_used(&dirty->root->root_item);
- root = dirty->latest_root;
- atomic_inc(&root->fs_info->throttles);
+ schedule();
- mutex_lock(&root->fs_info->drop_mutex);
- while(1) {
- trans = btrfs_start_transaction(tree_root, 1);
- ret = btrfs_drop_snapshot(trans, dirty->root);
- if (ret != -EAGAIN) {
- break;
- }
+ mutex_lock(&info->trans_mutex);
+ finish_wait(&info->transaction_wait, &wait);
+ }
+ mutex_unlock(&info->trans_mutex);
+ return 0;
+}
- err = btrfs_update_root(trans,
- tree_root,
- &dirty->root->root_key,
- &dirty->root->root_item);
- if (err)
- ret = err;
- nr = trans->blocks_used;
- ret = btrfs_end_transaction_throttle(trans, tree_root);
- BUG_ON(ret);
+/*
+ * Given a list of roots that need to be deleted, call btrfs_drop_snapshot on
+ * all of them
+ */
+int btrfs_drop_dead_root(struct btrfs_root *root)
+{
+ struct btrfs_trans_handle *trans;
+ struct btrfs_root *tree_root = root->fs_info->tree_root;
+ unsigned long nr;
+ int ret;
- mutex_unlock(&root->fs_info->drop_mutex);
- btrfs_btree_balance_dirty(tree_root, nr);
- cond_resched();
- mutex_lock(&root->fs_info->drop_mutex);
- }
- BUG_ON(ret);
- atomic_dec(&root->fs_info->throttles);
-
- mutex_lock(&root->fs_info->alloc_mutex);
- num_bytes -= btrfs_root_used(&dirty->root->root_item);
- bytes_used = btrfs_root_used(&root->root_item);
- if (num_bytes) {
- record_root_in_trans(root);
- btrfs_set_root_used(&root->root_item,
- bytes_used - num_bytes);
+ while (1) {
+ /*
+ * we don't want to jump in and create a bunch of
+ * delayed refs if the transaction is starting to close
+ */
+ wait_transaction_pre_flush(tree_root->fs_info);
+ trans = btrfs_start_transaction(tree_root, 1);
+
+ /*
+ * we've joined a transaction, make sure it isn't
+ * closing right now
+ */
+ if (trans->transaction->delayed_refs.flushing) {
+ btrfs_end_transaction(trans, tree_root);
+ continue;
}
- mutex_unlock(&root->fs_info->alloc_mutex);
- ret = btrfs_del_root(trans, tree_root, &dirty->root->root_key);
- if (ret) {
- BUG();
+ ret = btrfs_drop_snapshot(trans, root);
+ if (ret != -EAGAIN)
+ break;
+
+ ret = btrfs_update_root(trans, tree_root,
+ &root->root_key,
+ &root->root_item);
+ if (ret)
break;
- }
- mutex_unlock(&root->fs_info->drop_mutex);
nr = trans->blocks_used;
ret = btrfs_end_transaction(trans, tree_root);
BUG_ON(ret);
- btrfs_remove_leaf_refs(dirty->root);
-
- free_extent_buffer(dirty->root->node);
- kfree(dirty->root);
- kfree(dirty);
-
btrfs_btree_balance_dirty(tree_root, nr);
cond_resched();
}
+ BUG_ON(ret);
+
+ ret = btrfs_del_root(trans, tree_root, &root->root_key);
+ BUG_ON(ret);
+
+ nr = trans->blocks_used;
+ ret = btrfs_end_transaction(trans, tree_root);
+ BUG_ON(ret);
+
+ free_extent_buffer(root->node);
+ free_extent_buffer(root->commit_root);
+ kfree(root);
+
+ btrfs_btree_balance_dirty(tree_root, nr);
return ret;
}
+#endif
+/*
+ * new snapshots need to be created at a very specific time in the
+ * transaction commit. This does the actual creation
+ */
static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info,
struct btrfs_pending_snapshot *pending)
struct btrfs_root_item *new_root_item;
struct btrfs_root *tree_root = fs_info->tree_root;
struct btrfs_root *root = pending->root;
+ struct btrfs_root *parent_root;
+ struct inode *parent_inode;
+ struct dentry *dentry;
struct extent_buffer *tmp;
struct extent_buffer *old;
int ret;
- int namelen;
+ int retries = 0;
+ u64 to_reserve = 0;
+ u64 index = 0;
u64 objectid;
new_root_item = kmalloc(sizeof(*new_root_item), GFP_NOFS);
if (!new_root_item) {
- ret = -ENOMEM;
+ pending->error = -ENOMEM;
goto fail;
}
+
ret = btrfs_find_free_objectid(trans, tree_root, 0, &objectid);
- if (ret)
+ if (ret) {
+ pending->error = ret;
goto fail;
+ }
- memcpy(new_root_item, &root->root_item, sizeof(*new_root_item));
+ btrfs_reloc_pre_snapshot(trans, pending, &to_reserve);
+ btrfs_orphan_pre_snapshot(trans, pending, &to_reserve);
+
+ if (to_reserve > 0) {
+ ret = btrfs_block_rsv_add(trans, root, &pending->block_rsv,
+ to_reserve, &retries);
+ if (ret) {
+ pending->error = ret;
+ goto fail;
+ }
+ }
key.objectid = objectid;
- key.offset = 1;
- btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
+ key.offset = (u64)-1;
+ key.type = BTRFS_ROOT_ITEM_KEY;
+
+ trans->block_rsv = &pending->block_rsv;
+
+ dentry = pending->dentry;
+ parent_inode = dentry->d_parent->d_inode;
+ parent_root = BTRFS_I(parent_inode)->root;
+ record_root_in_trans(trans, parent_root);
+
+ /*
+ * insert the directory item
+ */
+ ret = btrfs_set_inode_index(parent_inode, &index);
+ BUG_ON(ret);
+ ret = btrfs_insert_dir_item(trans, parent_root,
+ dentry->d_name.name, dentry->d_name.len,
+ parent_inode->i_ino, &key,
+ BTRFS_FT_DIR, index);
+ BUG_ON(ret);
+
+ btrfs_i_size_write(parent_inode, parent_inode->i_size +
+ dentry->d_name.len * 2);
+ ret = btrfs_update_inode(trans, parent_root, parent_inode);
+ BUG_ON(ret);
+
+ record_root_in_trans(trans, root);
+ btrfs_set_root_last_snapshot(&root->root_item, trans->transid);
+ memcpy(new_root_item, &root->root_item, sizeof(*new_root_item));
old = btrfs_lock_root_node(root);
btrfs_cow_block(trans, root, old, NULL, 0, &old);
+ btrfs_set_lock_blocking(old);
btrfs_copy_root(trans, root, old, &tmp, objectid);
btrfs_tree_unlock(old);
free_extent_buffer(old);
- btrfs_set_root_bytenr(new_root_item, tmp->start);
- btrfs_set_root_level(new_root_item, btrfs_header_level(tmp));
- ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
- new_root_item);
+ btrfs_set_root_node(new_root_item, tmp);
+ /* record when the snapshot was created in key.offset */
+ key.offset = trans->transid;
+ ret = btrfs_insert_root(trans, tree_root, &key, new_root_item);
btrfs_tree_unlock(tmp);
free_extent_buffer(tmp);
- if (ret)
- goto fail;
+ BUG_ON(ret);
/*
- * insert the directory item
+ * insert root back/forward references
*/
- key.offset = (u64)-1;
- namelen = strlen(pending->name);
- ret = btrfs_insert_dir_item(trans, root->fs_info->tree_root,
- pending->name, namelen,
- root->fs_info->sb->s_root->d_inode->i_ino,
- &key, BTRFS_FT_DIR, 0);
-
- if (ret)
- goto fail;
-
- ret = btrfs_insert_inode_ref(trans, root->fs_info->tree_root,
- pending->name, strlen(pending->name), objectid,
- root->fs_info->sb->s_root->d_inode->i_ino, 0);
+ ret = btrfs_add_root_ref(trans, tree_root, objectid,
+ parent_root->root_key.objectid,
+ parent_inode->i_ino, index,
+ dentry->d_name.name, dentry->d_name.len);
+ BUG_ON(ret);
- /* Invalidate existing dcache entry for new snapshot. */
- btrfs_invalidate_dcache_root(root, pending->name, namelen);
+ key.offset = (u64)-1;
+ pending->snap = btrfs_read_fs_root_no_name(root->fs_info, &key);
+ BUG_ON(IS_ERR(pending->snap));
+ btrfs_reloc_post_snapshot(trans, pending);
+ btrfs_orphan_post_snapshot(trans, pending);
fail:
kfree(new_root_item);
- return ret;
+ btrfs_block_rsv_release(root, &pending->block_rsv, (u64)-1);
+ return 0;
}
+/*
+ * create all the snapshots we've scheduled for creation
+ */
static noinline int create_pending_snapshots(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info)
{
struct list_head *head = &trans->transaction->pending_snapshots;
int ret;
- while(!list_empty(head)) {
- pending = list_entry(head->next,
- struct btrfs_pending_snapshot, list);
+ list_for_each_entry(pending, head, list) {
ret = create_pending_snapshot(trans, fs_info, pending);
BUG_ON(ret);
- list_del(&pending->list);
- kfree(pending->name);
- kfree(pending);
}
return 0;
}
+static void update_super_roots(struct btrfs_root *root)
+{
+ struct btrfs_root_item *root_item;
+ struct btrfs_super_block *super;
+
+ super = &root->fs_info->super_copy;
+
+ root_item = &root->fs_info->chunk_root->root_item;
+ super->chunk_root = root_item->bytenr;
+ super->chunk_root_generation = root_item->generation;
+ super->chunk_root_level = root_item->level;
+
+ root_item = &root->fs_info->tree_root->root_item;
+ super->root = root_item->bytenr;
+ super->generation = root_item->generation;
+ super->root_level = root_item->level;
+}
+
+int btrfs_transaction_in_commit(struct btrfs_fs_info *info)
+{
+ int ret = 0;
+ spin_lock(&info->new_trans_lock);
+ if (info->running_transaction)
+ ret = info->running_transaction->in_commit;
+ spin_unlock(&info->new_trans_lock);
+ return ret;
+}
+
+int btrfs_transaction_blocked(struct btrfs_fs_info *info)
+{
+ int ret = 0;
+ spin_lock(&info->new_trans_lock);
+ if (info->running_transaction)
+ ret = info->running_transaction->blocked;
+ spin_unlock(&info->new_trans_lock);
+ return ret;
+}
+
int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
struct btrfs_root *root)
{
unsigned long timeout = 1;
struct btrfs_transaction *cur_trans;
struct btrfs_transaction *prev_trans = NULL;
- struct btrfs_root *chunk_root = root->fs_info->chunk_root;
- struct list_head dirty_fs_roots;
- struct extent_io_tree *pinned_copy;
DEFINE_WAIT(wait);
int ret;
+ int should_grow = 0;
+ unsigned long now = get_seconds();
+ int flush_on_commit = btrfs_test_opt(root, FLUSHONCOMMIT);
+
+ btrfs_run_ordered_operations(root, 0);
+
+ /* make a pass through all the delayed refs we have so far
+ * any runnings procs may add more while we are here
+ */
+ ret = btrfs_run_delayed_refs(trans, root, 0);
+ BUG_ON(ret);
+
+ btrfs_trans_release_metadata(trans, root);
- INIT_LIST_HEAD(&dirty_fs_roots);
+ cur_trans = trans->transaction;
+ /*
+ * set the flushing flag so procs in this transaction have to
+ * start sending their work down.
+ */
+ cur_trans->delayed_refs.flushing = 1;
+
+ ret = btrfs_run_delayed_refs(trans, root, 0);
+ BUG_ON(ret);
mutex_lock(&root->fs_info->trans_mutex);
- if (trans->transaction->in_commit) {
- cur_trans = trans->transaction;
- trans->transaction->use_count++;
+ if (cur_trans->in_commit) {
+ cur_trans->use_count++;
mutex_unlock(&root->fs_info->trans_mutex);
btrfs_end_transaction(trans, root);
return 0;
}
- pinned_copy = kmalloc(sizeof(*pinned_copy), GFP_NOFS);
- if (!pinned_copy)
- return -ENOMEM;
-
- extent_io_tree_init(pinned_copy,
- root->fs_info->btree_inode->i_mapping, GFP_NOFS);
-
trans->transaction->in_commit = 1;
trans->transaction->blocked = 1;
- cur_trans = trans->transaction;
if (cur_trans->list.prev != &root->fs_info->trans_list) {
prev_trans = list_entry(cur_trans->list.prev,
struct btrfs_transaction, list);
}
}
+ if (now < cur_trans->start_time || now - cur_trans->start_time < 1)
+ should_grow = 1;
+
do {
+ int snap_pending = 0;
joined = cur_trans->num_joined;
- WARN_ON(cur_trans != trans->transaction);
- prepare_to_wait(&cur_trans->writer_wait, &wait,
- TASK_UNINTERRUPTIBLE);
+ if (!list_empty(&trans->transaction->pending_snapshots))
+ snap_pending = 1;
+ WARN_ON(cur_trans != trans->transaction);
if (cur_trans->num_writers > 1)
timeout = MAX_SCHEDULE_TIMEOUT;
- else
+ else if (should_grow)
timeout = 1;
mutex_unlock(&root->fs_info->trans_mutex);
- schedule_timeout(timeout);
+ if (flush_on_commit || snap_pending) {
+ btrfs_start_delalloc_inodes(root, 1);
+ ret = btrfs_wait_ordered_extents(root, 0, 1);
+ BUG_ON(ret);
+ }
+
+ /*
+ * rename don't use btrfs_join_transaction, so, once we
+ * set the transaction to blocked above, we aren't going
+ * to get any new ordered operations. We can safely run
+ * it here and no for sure that nothing new will be added
+ * to the list
+ */
+ btrfs_run_ordered_operations(root, 1);
+
+ prepare_to_wait(&cur_trans->writer_wait, &wait,
+ TASK_UNINTERRUPTIBLE);
+
+ smp_mb();
+ if (cur_trans->num_writers > 1 || should_grow)
+ schedule_timeout(timeout);
mutex_lock(&root->fs_info->trans_mutex);
finish_wait(&cur_trans->writer_wait, &wait);
} while (cur_trans->num_writers > 1 ||
- (cur_trans->num_joined != joined));
+ (should_grow && cur_trans->num_joined != joined));
ret = create_pending_snapshots(trans, root->fs_info);
BUG_ON(ret);
+ ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1);
+ BUG_ON(ret);
+
WARN_ON(cur_trans != trans->transaction);
- ret = add_dirty_roots(trans, &root->fs_info->fs_roots_radix,
- &dirty_fs_roots);
+ /* btrfs_commit_tree_roots is responsible for getting the
+ * various roots consistent with each other. Every pointer
+ * in the tree of tree roots has to point to the most up to date
+ * root for every subvolume and other tree. So, we have to keep
+ * the tree logging code from jumping in and changing any
+ * of the trees.
+ *
+ * At this point in the commit, there can't be any tree-log
+ * writers, but a little lower down we drop the trans mutex
+ * and let new people in. By holding the tree_log_mutex
+ * from now until after the super is written, we avoid races
+ * with the tree-log code.
+ */
+ mutex_lock(&root->fs_info->tree_log_mutex);
+
+ ret = commit_fs_roots(trans, root);
BUG_ON(ret);
- spin_lock(&root->fs_info->ref_cache_lock);
- root->fs_info->running_ref_cache_size = 0;
- spin_unlock(&root->fs_info->ref_cache_lock);
+ /* commit_fs_roots gets rid of all the tree log roots, it is now
+ * safe to free the root of tree log roots
+ */
+ btrfs_free_log_root_tree(trans, root->fs_info);
- ret = btrfs_commit_tree_roots(trans, root);
+ ret = commit_cowonly_roots(trans, root);
BUG_ON(ret);
+ btrfs_prepare_extent_commit(trans, root);
+
cur_trans = root->fs_info->running_transaction;
spin_lock(&root->fs_info->new_trans_lock);
root->fs_info->running_transaction = NULL;
spin_unlock(&root->fs_info->new_trans_lock);
- btrfs_set_super_generation(&root->fs_info->super_copy,
- cur_trans->transid);
- btrfs_set_super_root(&root->fs_info->super_copy,
- root->fs_info->tree_root->node->start);
- btrfs_set_super_root_level(&root->fs_info->super_copy,
- btrfs_header_level(root->fs_info->tree_root->node));
-
- btrfs_set_super_chunk_root(&root->fs_info->super_copy,
- chunk_root->node->start);
- btrfs_set_super_chunk_root_level(&root->fs_info->super_copy,
- btrfs_header_level(chunk_root->node));
+
+ btrfs_set_root_node(&root->fs_info->tree_root->root_item,
+ root->fs_info->tree_root->node);
+ switch_commit_root(root->fs_info->tree_root);
+
+ btrfs_set_root_node(&root->fs_info->chunk_root->root_item,
+ root->fs_info->chunk_root->node);
+ switch_commit_root(root->fs_info->chunk_root);
+
+ update_super_roots(root);
+
+ if (!root->fs_info->log_root_recovering) {
+ btrfs_set_super_log_root(&root->fs_info->super_copy, 0);
+ btrfs_set_super_log_root_level(&root->fs_info->super_copy, 0);
+ }
+
memcpy(&root->fs_info->super_for_commit, &root->fs_info->super_copy,
sizeof(root->fs_info->super_copy));
- btrfs_copy_pinned(root, pinned_copy);
-
trans->transaction->blocked = 0;
- wake_up(&root->fs_info->transaction_throttle);
+
wake_up(&root->fs_info->transaction_wait);
mutex_unlock(&root->fs_info->trans_mutex);
ret = btrfs_write_and_wait_transaction(trans, root);
BUG_ON(ret);
- write_ctree_super(trans, root);
+ write_ctree_super(trans, root, 0);
- btrfs_finish_extent_commit(trans, root, pinned_copy);
- mutex_lock(&root->fs_info->trans_mutex);
+ /*
+ * the super is written, we can safely allow the tree-loggers
+ * to go about their business
+ */
+ mutex_unlock(&root->fs_info->tree_log_mutex);
- kfree(pinned_copy);
+ btrfs_finish_extent_commit(trans, root);
+
+ mutex_lock(&root->fs_info->trans_mutex);
cur_trans->commit_done = 1;
+
root->fs_info->last_trans_committed = cur_trans->transid;
+
wake_up(&cur_trans->commit_wait);
+
put_transaction(cur_trans);
put_transaction(cur_trans);
- if (root->fs_info->closing)
- list_splice_init(&root->fs_info->dead_roots, &dirty_fs_roots);
- else
- list_splice_init(&dirty_fs_roots, &root->fs_info->dead_roots);
-
mutex_unlock(&root->fs_info->trans_mutex);
+
+ if (current->journal_info == trans)
+ current->journal_info = NULL;
+
kmem_cache_free(btrfs_trans_handle_cachep, trans);
- if (root->fs_info->closing) {
- drop_dirty_roots(root->fs_info->tree_root, &dirty_fs_roots);
- }
+ if (current != root->fs_info->transaction_kthread)
+ btrfs_run_delayed_iputs(root);
+
return ret;
}
+/*
+ * interface function to delete all the snapshots we have scheduled for deletion
+ */
int btrfs_clean_old_snapshots(struct btrfs_root *root)
{
- struct list_head dirty_roots;
- INIT_LIST_HEAD(&dirty_roots);
-again:
- mutex_lock(&root->fs_info->trans_mutex);
- list_splice_init(&root->fs_info->dead_roots, &dirty_roots);
- mutex_unlock(&root->fs_info->trans_mutex);
+ LIST_HEAD(list);
+ struct btrfs_fs_info *fs_info = root->fs_info;
- if (!list_empty(&dirty_roots)) {
- drop_dirty_roots(root, &dirty_roots);
- goto again;
+ mutex_lock(&fs_info->trans_mutex);
+ list_splice_init(&fs_info->dead_roots, &list);
+ mutex_unlock(&fs_info->trans_mutex);
+
+ while (!list_empty(&list)) {
+ root = list_entry(list.next, struct btrfs_root, root_list);
+ list_del(&root->root_list);
+
+ if (btrfs_header_backref_rev(root->node) <
+ BTRFS_MIXED_BACKREF_REV)
+ btrfs_drop_snapshot(root, NULL, 0);
+ else
+ btrfs_drop_snapshot(root, NULL, 1);
}
return 0;
}
-
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff