Btrfs: get rid of add recursion

Signed-off-by: Chris Mason <chris.mason@oracle.com>

diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile
index ae7f4c0..d92d08d 100644 (file)
--- a/fs/btrfs/Makefile
+++ b/fs/btrfs/Makefile
@@ -1,6 +1,6 @@
 
 CC=gcc
-CFLAGS = -g -Wall
+CFLAGS = -Wall
 headers = radix-tree.h ctree.h disk-io.h kerncompat.h print-tree.h list.h
 objects = ctree.o disk-io.o radix-tree.o mkfs.o extent-tree.o print-tree.o
 

diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 7281638..729d4dd 100644 (file)
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -995,15 +995,6 @@ static int split_leaf(struct ctree_root *root, struct ctree_path *path,
        int ret;
        int wret;
 
-       wret = push_leaf_left(root, path, data_size);
-       if (wret < 0)
-               return wret;
-       if (wret) {
-               wret = push_leaf_right(root, path, data_size);
-               if (wret < 0)
-                       return wret;
-       }
-
        l_buf = path->nodes[0];
        l = &l_buf->leaf;
 

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 0723b7f..8a2b8aa 100644 (file)
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -6,6 +6,11 @@
 #include "disk-io.h"
 #include "print-tree.h"
 
+static int find_free_extent(struct ctree_root *orig_root, u64 num_blocks,
+                           u64 search_start, u64 search_end, struct key *ins);
+static int finish_current_insert(struct ctree_root *extent_root);
+static int run_pending(struct ctree_root *extent_root);
+
 /*
  * pending extents are blocks that we're trying to allocate in the extent
  * map while trying to grow the map because of other allocations.  To avoid
@@ -13,8 +18,7 @@
  * other allocations are done.  The pending tag is also used in the same
  * manner for deletes.
  */
-#define CTREE_EXTENT_PENDING_ADD 0
-#define CTREE_EXTENT_PENDING_DEL 1
+#define CTREE_EXTENT_PENDING_DEL 0
 
 static int inc_block_ref(struct ctree_root *root, u64 blocknr)
 {
@@ -23,6 +27,9 @@ static int inc_block_ref(struct ctree_root *root, u64 blocknr)
        struct key key;
        struct leaf *l;
        struct extent_item *item;
+       struct key ins;
+
+       find_free_extent(root->extent_root, 0, 0, (u64)-1, &ins);
        init_path(&path);
        key.objectid = blocknr;
        key.flags = 0;
@@ -38,6 +45,8 @@ static int inc_block_ref(struct ctree_root *root, u64 blocknr)
 
        BUG_ON(list_empty(&path.nodes[0]->dirty));
        release_path(root->extent_root, &path);
+       finish_current_insert(root->extent_root);
+       run_pending(root->extent_root);
        return 0;
 }
 
@@ -99,6 +108,28 @@ int btrfs_finish_extent_commit(struct ctree_root *root)
        return 0;
 }
 
+static int finish_current_insert(struct ctree_root *extent_root)
+{
+       struct key ins;
+       struct extent_item extent_item;
+       int i;
+       int ret;
+
+       extent_item.refs = 1;
+       extent_item.owner = extent_root->node->node.header.parentid;
+       ins.offset = 1;
+       ins.flags = 0;
+
+       for (i = 0; i < extent_root->current_insert.flags; i++) {
+               ins.objectid = extent_root->current_insert.objectid + i;
+               ret = insert_item(extent_root, &ins, &extent_item,
+                                 sizeof(extent_item));
+               BUG_ON(ret);
+       }
+       extent_root->current_insert.offset = 0;
+       return 0;
+}
+
 /*
  * remove an extent from the root, returns 0 on success
  */
@@ -110,10 +141,13 @@ int __free_extent(struct ctree_root *root, u64 blocknr, u64 num_blocks)
        int ret;
        struct item *item;
        struct extent_item *ei;
+       struct key ins;
+
        key.objectid = blocknr;
        key.flags = 0;
        key.offset = num_blocks;
 
+       find_free_extent(root, 0, 0, (u64)-1, &ins);
        init_path(&path);
        ret = search_slot(extent_root, &key, &path, -1, 1);
        if (ret) {
@@ -140,54 +174,11 @@ int __free_extent(struct ctree_root *root, u64 blocknr, u64 num_blocks)
                        BUG();
        }
        release_path(extent_root, &path);
+       finish_current_insert(extent_root);
        return ret;
 }
 
 /*
- * insert all of the pending extents reserved during the original
- * allocation.  (CTREE_EXTENT_PENDING).  Returns zero if it all worked out
- */
-static int insert_pending_extents(struct ctree_root *extent_root)
-{
-       int ret;
-       struct key key;
-       struct extent_item item;
-       struct tree_buffer *gang[4];
-       int i;
-
-       // FIXME -ENOSPC
-       item.owner = extent_root->node->node.header.parentid;
-       item.refs = 1;
-       while(1) {
-               ret = radix_tree_gang_lookup_tag(&extent_root->cache_radix,
-                                                (void **)gang, 0,
-                                                ARRAY_SIZE(gang),
-                                                CTREE_EXTENT_PENDING_ADD);
-               if (!ret)
-                       break;
-               for (i = 0; i < ret; i++) {
-                       key.objectid = gang[i]->blocknr;
-                       key.flags = 0;
-                       key.offset = 1;
-                       ret = insert_item(extent_root, &key, &item,
-                                         sizeof(item));
-                       if (ret) {
-                               printf("%Lu already in tree\n", key.objectid);
-                               print_tree(extent_root, extent_root->node);
-                               BUG();
-                               // FIXME undo it and return sane
-                               return ret;
-                       }
-                       radix_tree_tag_clear(&extent_root->cache_radix,
-                                            gang[i]->blocknr,
-                                            CTREE_EXTENT_PENDING_ADD);
-                       tree_block_release(extent_root, gang[i]);
-               }
-       }
-       return 0;
-}
-
-/*
  * find all the blocks marked as pending in the radix tree and remove
  * them from the extent map
  */
@@ -218,12 +209,8 @@ static int del_pending_extents(struct ctree_root *extent_root)
 static int run_pending(struct ctree_root *extent_root)
 {
        while(radix_tree_tagged(&extent_root->cache_radix,
-                               CTREE_EXTENT_PENDING_DEL) ||
-             radix_tree_tagged(&extent_root->cache_radix,
-                               CTREE_EXTENT_PENDING_ADD)) {
-               insert_pending_extents(extent_root);
+                               CTREE_EXTENT_PENDING_DEL))
                del_pending_extents(extent_root);
-       }
        return 0;
 }
 
@@ -241,19 +228,8 @@ int free_extent(struct ctree_root *root, u64 blocknr, u64 num_blocks)
 
        if (root == extent_root) {
                t = find_tree_block(root, blocknr);
-               if (radix_tree_tag_get(&root->cache_radix, blocknr,
-                                     CTREE_EXTENT_PENDING_ADD)) {
-                       radix_tree_tag_clear(&root->cache_radix,
-                                            blocknr,
-                                            CTREE_EXTENT_PENDING_ADD);
-                       /* once for us */
-                       tree_block_release(root, t);
-                       /* once for the pending add */
-                       tree_block_release(root, t);
-               } else {
-                       radix_tree_tag_set(&root->cache_radix, blocknr,
+               radix_tree_tag_set(&root->cache_radix, blocknr,
                                   CTREE_EXTENT_PENDING_DEL);
-               }
                return 0;
        }
        key.objectid = blocknr;
@@ -281,9 +257,11 @@ static int find_free_extent(struct ctree_root *orig_root, u64 num_blocks,
        u64 hole_size = 0;
        int slot = 0;
        u64 last_block;
+       u64 test_block;
        int start_found;
        struct leaf *l;
        struct ctree_root * root = orig_root->extent_root;
+       int total_needed = num_blocks + MAX_LEVEL * 3;
 
 check_failed:
        init_path(&path);
@@ -306,22 +284,34 @@ check_failed:
                                goto error;
                        if (!start_found) {
                                ins->objectid = search_start;
-                               ins->offset = num_blocks;
+                               ins->offset = (u64)-1;
                                start_found = 1;
                                goto check_pending;
                        }
                        ins->objectid = last_block > search_start ?
                                        last_block : search_start;
-                       ins->offset = num_blocks;
+                       ins->offset = (u64)-1;
                        goto check_pending;
                }
+               if (slot == 0) {
+                       int last_slot = l->header.nritems - 1;
+                       u64 span = l->items[last_slot].key.objectid;
+                       span -= l->items[slot].key.objectid;
+                       if (span + total_needed > last_slot - slot) {
+                               path.slots[0] = last_slot + 1;
+                               key = &l->items[last_slot].key;
+                               last_block = key->objectid + key->offset;
+                               start_found = 1;
+                               continue;
+                       }
+               }
                key = &l->items[slot].key;
                if (key->objectid >= search_start) {
                        if (start_found) {
                                hole_size = key->objectid - last_block;
-                               if (hole_size > num_blocks) {
+                               if (hole_size > total_needed) {
                                        ins->objectid = last_block;
-                                       ins->offset = num_blocks;
+                                       ins->offset = hole_size;
                                        goto check_pending;
                                }
                        } else
@@ -337,23 +327,18 @@ check_pending:
         */
        release_path(root, &path);
        BUG_ON(ins->objectid < search_start);
-       if (1 || orig_root->extent_root == orig_root) {
-               BUG_ON(num_blocks != 1);
-               if ((root->current_insert.objectid <= ins->objectid &&
-                   root->current_insert.objectid +
-                   root->current_insert.offset > ins->objectid) ||
-                  (root->current_insert.objectid > ins->objectid &&
-                   root->current_insert.objectid <= ins->objectid +
-                   ins->offset) ||
-                  radix_tree_lookup(&root->pinned_radix, ins->objectid) ||
-                  radix_tree_tag_get(&root->cache_radix, ins->objectid,
-                                     CTREE_EXTENT_PENDING_ADD)) {
-                       search_start = ins->objectid + 1;
+       for (test_block = ins->objectid;
+            test_block < ins->objectid + total_needed; test_block++) {
+               if (radix_tree_lookup(&root->pinned_radix, test_block)) {
+                       search_start = test_block + 1;
                        goto check_failed;
                }
        }
-       if (ins->offset != 1)
-               BUG();
+       BUG_ON(root->current_insert.offset);
+       root->current_insert.offset = total_needed;
+       root->current_insert.objectid = ins->objectid + num_blocks;
+       root->current_insert.flags = 0;
+       ins->offset = num_blocks;
        return 0;
 error:
        release_path(root, &path);
@@ -368,43 +353,41 @@ error:
  * returns 0 if everything worked, non-zero otherwise.
  */
 int alloc_extent(struct ctree_root *root, u64 num_blocks, u64 search_start,
-                        u64 search_end, u64 owner, struct key *ins,
-                        struct tree_buffer **buf)
+                        u64 search_end, u64 owner, struct key *ins)
 {
        int ret;
        int pending_ret;
+       struct ctree_root *extent_root = root->extent_root;
        struct extent_item extent_item;
+
        extent_item.refs = 1;
        extent_item.owner = owner;
 
-       ret = find_free_extent(root, num_blocks, search_start, search_end, ins);
-       if (ret)
-               return ret;
-       if (root != root->extent_root) {
-               memcpy(&root->extent_root->current_insert, ins, sizeof(*ins));
-               ret = insert_item(root->extent_root, ins, &extent_item,
-                                 sizeof(extent_item));
-               memset(&root->extent_root->current_insert, 0,
-                      sizeof(struct key));
-               pending_ret = run_pending(root->extent_root);
-               if (ret)
-                       return ret;
-               if (pending_ret)
-                       return pending_ret;
-               *buf = find_tree_block(root, ins->objectid);
-               dirty_tree_block(root, *buf);
+       if (root == extent_root) {
+               BUG_ON(extent_root->current_insert.offset == 0);
+               BUG_ON(num_blocks != 1);
+               BUG_ON(extent_root->current_insert.flags ==
+                      extent_root->current_insert.offset);
+               ins->offset = 1;
+               ins->objectid = extent_root->current_insert.objectid +
+                               extent_root->current_insert.flags++;
                return 0;
        }
-       /* we're allocating an extent for the extent tree, don't recurse */
-       BUG_ON(ins->offset != 1);
-       *buf = find_tree_block(root, ins->objectid);
-       BUG_ON(!*buf);
-       radix_tree_tag_set(&root->cache_radix, ins->objectid,
-                          CTREE_EXTENT_PENDING_ADD);
-       (*buf)->count++;
-       dirty_tree_block(root, *buf);
-       return 0;
+       ret = find_free_extent(root, num_blocks, search_start,
+                              search_end, ins);
+       if (ret)
+               return ret;
 
+       ret = insert_item(extent_root, ins, &extent_item,
+                         sizeof(extent_item));
+
+       finish_current_insert(extent_root);
+       pending_ret = run_pending(extent_root);
+       if (ret)
+               return ret;
+       if (pending_ret)
+               return pending_ret;
+       return 0;
 }
 
 /*
@@ -415,19 +398,17 @@ struct tree_buffer *alloc_free_block(struct ctree_root *root)
 {
        struct key ins;
        int ret;
-       struct tree_buffer *buf = NULL;
+       struct tree_buffer *buf;
 
        ret = alloc_extent(root, 1, 0, (unsigned long)-1,
                           root->node->node.header.parentid,
-                          &ins, &buf);
+                          &ins);
        if (ret) {
                BUG();
                return NULL;
        }
-       if (root != root->extent_root)
-               BUG_ON(radix_tree_tag_get(&root->extent_root->cache_radix,
-                                         buf->blocknr,
-                                         CTREE_EXTENT_PENDING_ADD));
+       buf = find_tree_block(root, ins.objectid);
+       dirty_tree_block(root, buf);
        return buf;
 }