diff options
| -rw-r--r-- | fs/btrfs/inode.c | 35 |
1 files changed, 33 insertions, 2 deletions
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index b83a45dc717..9b4faac50c1 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -1497,6 +1497,30 @@ static int insert_reserved_file_extent(struct btrfs_trans_handle *trans, return 0; } +/* + * helper function for btrfs_finish_ordered_io, this + * just reads in some of the csum leaves to prime them into ram + * before we start the transaction. It limits the amount of btree + * reads required while inside the transaction. + */ +static noinline void reada_csum(struct btrfs_root *root, + struct btrfs_path *path, + struct btrfs_ordered_extent *ordered_extent) +{ + struct btrfs_ordered_sum *sum; + u64 bytenr; + + sum = list_entry(ordered_extent->list.next, struct btrfs_ordered_sum, + list); + bytenr = sum->sums[0].bytenr; + + /* + * we don't care about the results, the point of this search is + * just to get the btree leaves into ram + */ + btrfs_lookup_csum(NULL, root->fs_info->csum_root, path, bytenr, 0); +} + /* as ordered data IO finishes, this gets called so we can finish * an ordered extent if the range of bytes in the file it covers are * fully written. @@ -1505,7 +1529,7 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end) { struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_trans_handle *trans; - struct btrfs_ordered_extent *ordered_extent; + struct btrfs_ordered_extent *ordered_extent = NULL; struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; struct btrfs_path *path; int compressed = 0; @@ -1528,13 +1552,20 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end) ret = btrfs_lookup_file_extent(NULL, root, path, inode->i_ino, start, 0); + ordered_extent = btrfs_lookup_ordered_extent(inode, + start); + if (!list_empty(&ordered_extent->list)) { + btrfs_release_path(root, path); + reada_csum(root, path, ordered_extent); + } btrfs_free_path(path); } } trans = btrfs_join_transaction(root, 1); - ordered_extent = btrfs_lookup_ordered_extent(inode, start); + if (!ordered_extent) + ordered_extent = btrfs_lookup_ordered_extent(inode, start); BUG_ON(!ordered_extent); if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) goto nocow; |