Yan, Zheng
2009-Nov-12 09:34 UTC
[PATCH 07/12] Btrfs: Make fallocate(2) more ENOSPC friendly
fallocate(2) may allocate large number of file extents, so it''s not
good to do it in a single transaction. This patch make fallocate(2)
start a new transaction for each file extents it allocates.
Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
---
fs/btrfs/inode.c | 65 ++++++++++++++++++++++++++---------------------------
1 files changed, 32 insertions(+), 33 deletions(-)
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 75a6647..f60cd94 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -5659,10 +5659,10 @@ out_fail:
return err;
}
-static int prealloc_file_range(struct btrfs_trans_handle *trans,
- struct inode *inode, u64 start, u64 end,
+static int prealloc_file_range(struct inode *inode, u64 start, u64 end,
u64 alloc_hint, int mode)
{
+ struct btrfs_trans_handle *trans;
struct btrfs_root *root = BTRFS_I(inode)->root;
struct btrfs_key ins;
u64 alloc_size;
@@ -5673,17 +5673,23 @@ static int prealloc_file_range(struct btrfs_trans_handle
*trans,
while (num_bytes > 0) {
alloc_size = min(num_bytes, root->fs_info->max_extent);
- ret = btrfs_reserve_metadata_space(root, 1);
- if (ret)
- goto out;
-
ret = btrfs_reserve_extent(trans, root, alloc_size,
root->sectorsize, 0, alloc_hint,
(u64)-1, &ins, 1);
if (ret) {
WARN_ON(1);
- goto out;
+ break;
+ }
+
+ ret = btrfs_reserve_metadata_space(root, 3);
+ if (ret) {
+ btrfs_free_reserved_extent(root, ins.objectid,
+ ins.offset);
+ break;
}
+
+ trans = btrfs_start_transaction(root, 1);
+
ret = insert_reserved_file_extent(trans, inode,
cur_offset, ins.objectid,
ins.offset, ins.offset,
@@ -5692,22 +5698,25 @@ static int prealloc_file_range(struct btrfs_trans_handle
*trans,
BUG_ON(ret);
btrfs_drop_extent_cache(inode, cur_offset,
cur_offset + ins.offset -1, 0);
+
num_bytes -= ins.offset;
cur_offset += ins.offset;
alloc_hint = ins.objectid + ins.offset;
- btrfs_unreserve_metadata_space(root, 1);
- }
-out:
- if (cur_offset > start) {
+
inode->i_ctime = CURRENT_TIME;
BTRFS_I(inode)->flags |= BTRFS_INODE_PREALLOC;
if (!(mode & FALLOC_FL_KEEP_SIZE) &&
- cur_offset > i_size_read(inode))
- btrfs_i_size_write(inode, cur_offset);
+ cur_offset > inode->i_size) {
+ i_size_write(inode, cur_offset);
+ btrfs_ordered_update_i_size(inode, cur_offset, NULL);
+ }
+
ret = btrfs_update_inode(trans, root, inode);
BUG_ON(ret);
- }
+ btrfs_end_transaction(trans, root);
+ btrfs_unreserve_metadata_space(root, 3);
+ }
return ret;
}
@@ -5722,8 +5731,6 @@ static long btrfs_fallocate(struct inode *inode, int mode,
u64 locked_end;
u64 mask = BTRFS_I(inode)->root->sectorsize - 1;
struct extent_map *em;
- struct btrfs_trans_handle *trans;
- struct btrfs_root *root;
int ret;
alloc_start = offset & ~mask;
@@ -5742,9 +5749,7 @@ static long btrfs_fallocate(struct inode *inode, int mode,
goto out;
}
- root = BTRFS_I(inode)->root;
-
- ret = btrfs_check_data_free_space(root, inode,
+ ret = btrfs_check_data_free_space(BTRFS_I(inode)->root, inode,
alloc_end - alloc_start);
if (ret)
goto out;
@@ -5753,12 +5758,6 @@ static long btrfs_fallocate(struct inode *inode, int
mode,
while (1) {
struct btrfs_ordered_extent *ordered;
- trans = btrfs_start_transaction(BTRFS_I(inode)->root, 1);
- if (!trans) {
- ret = -EIO;
- goto out_free;
- }
-
/* the extent lock is ordered inside the running
* transaction
*/
@@ -5772,8 +5771,6 @@ static long btrfs_fallocate(struct inode *inode, int mode,
btrfs_put_ordered_extent(ordered);
unlock_extent(&BTRFS_I(inode)->io_tree,
alloc_start, locked_end, GFP_NOFS);
- btrfs_end_transaction(trans, BTRFS_I(inode)->root);
-
/*
* we can''t wait on the range with the transaction
* running or with the extent lock held
@@ -5794,9 +5791,12 @@ static long btrfs_fallocate(struct inode *inode, int
mode,
BUG_ON(IS_ERR(em) || !em);
last_byte = min(extent_map_end(em), alloc_end);
last_byte = (last_byte + mask) & ~mask;
- if (em->block_start == EXTENT_MAP_HOLE) {
- ret = prealloc_file_range(trans, inode, cur_offset,
- last_byte, alloc_hint, mode);
+ if (em->block_start == EXTENT_MAP_HOLE ||
+ (cur_offset >= inode->i_size &&
+ !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) {
+ ret = prealloc_file_range(inode,
+ cur_offset, last_byte,
+ alloc_hint, mode);
if (ret < 0) {
free_extent_map(em);
break;
@@ -5815,9 +5815,8 @@ static long btrfs_fallocate(struct inode *inode, int mode,
unlock_extent(&BTRFS_I(inode)->io_tree, alloc_start, locked_end,
GFP_NOFS);
- btrfs_end_transaction(trans, BTRFS_I(inode)->root);
-out_free:
- btrfs_free_reserved_data_space(root, inode, alloc_end - alloc_start);
+ btrfs_free_reserved_data_space(BTRFS_I(inode)->root, inode,
+ alloc_end - alloc_start);
out:
mutex_unlock(&inode->i_mutex);
return ret;
--
1.6.2.5
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