From 5a303d5d4b8055d2e5a03e92d04745bfc5881a22 Mon Sep 17 00:00:00 2001 From: "Yan, Zheng" Date: Thu, 12 Nov 2009 09:34:52 +0000 Subject: [PATCH] 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 Signed-off-by: Chris Mason --- fs/btrfs/inode.c | 65 ++++++++++++++++++++++++------------------------ 1 file changed, 32 insertions(+), 33 deletions(-) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index eb2db3bde236..8d8baaa61504 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -5664,10 +5664,10 @@ 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; @@ -5678,17 +5678,23 @@ 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, @@ -5697,22 +5703,25 @@ 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; } @@ -5727,8 +5736,6 @@ 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; @@ -5747,9 +5754,7 @@ 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; @@ -5758,12 +5763,6 @@ 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 */ @@ -5777,8 +5776,6 @@ 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 @@ -5799,9 +5796,12 @@ 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; @@ -5820,9 +5820,8 @@ 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;