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authorYan, Zheng <zheng.yan@oracle.com>2010-05-16 10:46:25 -0400
committerChris Mason <chris.mason@oracle.com>2010-05-25 10:34:50 -0400
commitf0486c68e4bd9a06a5904d3eeb3a0d73a83befb8 (patch)
tree509428ef400ef45e875a3c448b63b86cbea36aea /fs/btrfs/ctree.c
parent2ead6ae770d9f9dec9f4286bf0fd9001b4388c4b (diff)
downloadlinux-f0486c68e4bd9a06a5904d3eeb3a0d73a83befb8.tar.bz2
Btrfs: Introduce contexts for metadata reservation
Introducing metadata reseravtion contexts has two major advantages. First, it makes metadata reseravtion more traceable. Second, it can reclaim freed space and re-add them to the itself after transaction committed. Besides add btrfs_block_rsv structure and related helper functions, This patch contains following changes: Move code that decides if freed tree block should be pinned into btrfs_free_tree_block(). Make space accounting more accurate, mainly for handling read only block groups. Signed-off-by: Chris Mason <chris.mason@oracle.com>
Diffstat (limited to 'fs/btrfs/ctree.c')
-rw-r--r--fs/btrfs/ctree.c104
1 files changed, 63 insertions, 41 deletions
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 6795a713b205..6bee8e5204fb 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -280,7 +280,8 @@ int btrfs_block_can_be_shared(struct btrfs_root *root,
static noinline int update_ref_for_cow(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct extent_buffer *buf,
- struct extent_buffer *cow)
+ struct extent_buffer *cow,
+ int *last_ref)
{
u64 refs;
u64 owner;
@@ -366,6 +367,7 @@ static noinline int update_ref_for_cow(struct btrfs_trans_handle *trans,
BUG_ON(ret);
}
clean_tree_block(trans, root, buf);
+ *last_ref = 1;
}
return 0;
}
@@ -392,6 +394,7 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans,
struct btrfs_disk_key disk_key;
struct extent_buffer *cow;
int level;
+ int last_ref = 0;
int unlock_orig = 0;
u64 parent_start;
@@ -442,7 +445,7 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans,
(unsigned long)btrfs_header_fsid(cow),
BTRFS_FSID_SIZE);
- update_ref_for_cow(trans, root, buf, cow);
+ update_ref_for_cow(trans, root, buf, cow, &last_ref);
if (buf == root->node) {
WARN_ON(parent && parent != buf);
@@ -457,8 +460,8 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans,
extent_buffer_get(cow);
spin_unlock(&root->node_lock);
- btrfs_free_tree_block(trans, root, buf->start, buf->len,
- parent_start, root->root_key.objectid, level);
+ btrfs_free_tree_block(trans, root, buf, parent_start,
+ last_ref);
free_extent_buffer(buf);
add_root_to_dirty_list(root);
} else {
@@ -473,8 +476,8 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans,
btrfs_set_node_ptr_generation(parent, parent_slot,
trans->transid);
btrfs_mark_buffer_dirty(parent);
- btrfs_free_tree_block(trans, root, buf->start, buf->len,
- parent_start, root->root_key.objectid, level);
+ btrfs_free_tree_block(trans, root, buf, parent_start,
+ last_ref);
}
if (unlock_orig)
btrfs_tree_unlock(buf);
@@ -949,6 +952,22 @@ int btrfs_bin_search(struct extent_buffer *eb, struct btrfs_key *key,
return bin_search(eb, key, level, slot);
}
+static void root_add_used(struct btrfs_root *root, u32 size)
+{
+ spin_lock(&root->accounting_lock);
+ btrfs_set_root_used(&root->root_item,
+ btrfs_root_used(&root->root_item) + size);
+ spin_unlock(&root->accounting_lock);
+}
+
+static void root_sub_used(struct btrfs_root *root, u32 size)
+{
+ spin_lock(&root->accounting_lock);
+ btrfs_set_root_used(&root->root_item,
+ btrfs_root_used(&root->root_item) - size);
+ spin_unlock(&root->accounting_lock);
+}
+
/* given a node and slot number, this reads the blocks it points to. The
* extent buffer is returned with a reference taken (but unlocked).
* NULL is returned on error.
@@ -1019,7 +1038,11 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
btrfs_tree_lock(child);
btrfs_set_lock_blocking(child);
ret = btrfs_cow_block(trans, root, child, mid, 0, &child);
- BUG_ON(ret);
+ if (ret) {
+ btrfs_tree_unlock(child);
+ free_extent_buffer(child);
+ goto enospc;
+ }
spin_lock(&root->node_lock);
root->node = child;
@@ -1034,11 +1057,12 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
btrfs_tree_unlock(mid);
/* once for the path */
free_extent_buffer(mid);
- ret = btrfs_free_tree_block(trans, root, mid->start, mid->len,
- 0, root->root_key.objectid, level);
+
+ root_sub_used(root, mid->len);
+ btrfs_free_tree_block(trans, root, mid, 0, 1);
/* once for the root ptr */
free_extent_buffer(mid);
- return ret;
+ return 0;
}
if (btrfs_header_nritems(mid) >
BTRFS_NODEPTRS_PER_BLOCK(root) / 4)
@@ -1088,23 +1112,16 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
if (wret < 0 && wret != -ENOSPC)
ret = wret;
if (btrfs_header_nritems(right) == 0) {
- u64 bytenr = right->start;
- u32 blocksize = right->len;
-
clean_tree_block(trans, root, right);
btrfs_tree_unlock(right);
- free_extent_buffer(right);
- right = NULL;
wret = del_ptr(trans, root, path, level + 1, pslot +
1);
if (wret)
ret = wret;
- wret = btrfs_free_tree_block(trans, root,
- bytenr, blocksize, 0,
- root->root_key.objectid,
- level);
- if (wret)
- ret = wret;
+ root_sub_used(root, right->len);
+ btrfs_free_tree_block(trans, root, right, 0, 1);
+ free_extent_buffer(right);
+ right = NULL;
} else {
struct btrfs_disk_key right_key;
btrfs_node_key(right, &right_key, 0);
@@ -1136,21 +1153,15 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
BUG_ON(wret == 1);
}
if (btrfs_header_nritems(mid) == 0) {
- /* we've managed to empty the middle node, drop it */
- u64 bytenr = mid->start;
- u32 blocksize = mid->len;
-
clean_tree_block(trans, root, mid);
btrfs_tree_unlock(mid);
- free_extent_buffer(mid);
- mid = NULL;
wret = del_ptr(trans, root, path, level + 1, pslot);
if (wret)
ret = wret;
- wret = btrfs_free_tree_block(trans, root, bytenr, blocksize,
- 0, root->root_key.objectid, level);
- if (wret)
- ret = wret;
+ root_sub_used(root, mid->len);
+ btrfs_free_tree_block(trans, root, mid, 0, 1);
+ free_extent_buffer(mid);
+ mid = NULL;
} else {
/* update the parent key to reflect our changes */
struct btrfs_disk_key mid_key;
@@ -1740,7 +1751,6 @@ again:
p->nodes[level + 1],
p->slots[level + 1], &b);
if (err) {
- free_extent_buffer(b);
ret = err;
goto done;
}
@@ -2076,6 +2086,8 @@ static noinline int insert_new_root(struct btrfs_trans_handle *trans,
if (IS_ERR(c))
return PTR_ERR(c);
+ root_add_used(root, root->nodesize);
+
memset_extent_buffer(c, 0, 0, sizeof(struct btrfs_header));
btrfs_set_header_nritems(c, 1);
btrfs_set_header_level(c, level);
@@ -2134,6 +2146,7 @@ static int insert_ptr(struct btrfs_trans_handle *trans, struct btrfs_root
int nritems;
BUG_ON(!path->nodes[level]);
+ btrfs_assert_tree_locked(path->nodes[level]);
lower = path->nodes[level];
nritems = btrfs_header_nritems(lower);
BUG_ON(slot > nritems);
@@ -2202,6 +2215,8 @@ static noinline int split_node(struct btrfs_trans_handle *trans,
if (IS_ERR(split))
return PTR_ERR(split);
+ root_add_used(root, root->nodesize);
+
memset_extent_buffer(split, 0, 0, sizeof(struct btrfs_header));
btrfs_set_header_level(split, btrfs_header_level(c));
btrfs_set_header_bytenr(split, split->start);
@@ -2415,6 +2430,9 @@ static noinline int __push_leaf_right(struct btrfs_trans_handle *trans,
if (left_nritems)
btrfs_mark_buffer_dirty(left);
+ else
+ clean_tree_block(trans, root, left);
+
btrfs_mark_buffer_dirty(right);
btrfs_item_key(right, &disk_key, 0);
@@ -2660,6 +2678,8 @@ static noinline int __push_leaf_left(struct btrfs_trans_handle *trans,
btrfs_mark_buffer_dirty(left);
if (right_nritems)
btrfs_mark_buffer_dirty(right);
+ else
+ clean_tree_block(trans, root, right);
btrfs_item_key(right, &disk_key, 0);
wret = fixup_low_keys(trans, root, path, &disk_key, 1);
@@ -2669,8 +2689,6 @@ static noinline int __push_leaf_left(struct btrfs_trans_handle *trans,
/* then fixup the leaf pointer in the path */
if (path->slots[0] < push_items) {
path->slots[0] += old_left_nritems;
- if (btrfs_header_nritems(path->nodes[0]) == 0)
- clean_tree_block(trans, root, path->nodes[0]);
btrfs_tree_unlock(path->nodes[0]);
free_extent_buffer(path->nodes[0]);
path->nodes[0] = left;
@@ -2932,10 +2950,10 @@ again:
right = btrfs_alloc_free_block(trans, root, root->leafsize, 0,
root->root_key.objectid,
&disk_key, 0, l->start, 0);
- if (IS_ERR(right)) {
- BUG_ON(1);
+ if (IS_ERR(right))
return PTR_ERR(right);
- }
+
+ root_add_used(root, root->leafsize);
memset_extent_buffer(right, 0, 0, sizeof(struct btrfs_header));
btrfs_set_header_bytenr(right, right->start);
@@ -3054,7 +3072,8 @@ static noinline int setup_leaf_for_split(struct btrfs_trans_handle *trans,
btrfs_set_path_blocking(path);
ret = split_leaf(trans, root, &key, path, ins_len, 1);
- BUG_ON(ret);
+ if (ret)
+ goto err;
path->keep_locks = 0;
btrfs_unlock_up_safe(path, 1);
@@ -3796,9 +3815,10 @@ static noinline int btrfs_del_leaf(struct btrfs_trans_handle *trans,
*/
btrfs_unlock_up_safe(path, 0);
- ret = btrfs_free_tree_block(trans, root, leaf->start, leaf->len,
- 0, root->root_key.objectid, 0);
- return ret;
+ root_sub_used(root, leaf->len);
+
+ btrfs_free_tree_block(trans, root, leaf, 0, 1);
+ return 0;
}
/*
* delete the item at the leaf level in path. If that empties
@@ -3865,6 +3885,8 @@ int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root,
if (leaf == root->node) {
btrfs_set_header_level(leaf, 0);
} else {
+ btrfs_set_path_blocking(path);
+ clean_tree_block(trans, root, leaf);
ret = btrfs_del_leaf(trans, root, path, leaf);
BUG_ON(ret);
}