From ff5df9b884268d319d041934c6059c09733a4be2 Mon Sep 17 00:00:00 2001 From: Filipe Manana Date: Fri, 30 May 2014 17:56:24 +0100 Subject: [PATCH] Btrfs: ioctl, don't re-lock extent range when not necessary In ioctl.c:lock_extent_range(), after locking our target range, the ordered extent that btrfs_lookup_first_ordered_extent() returns us may not overlap our target range at all. In this case we would just unlock our target range, wait for any new ordered extents that overlap the range to complete, lock again the range and repeat all these steps until we don't get any ordered extent and the delalloc flag isn't set in the io tree for our target range. Therefore just stop if we get an ordered extent that doesn't overlap our target range and the dealalloc flag isn't set for the range in the inode's io tree. Signed-off-by: Filipe David Borba Manana Signed-off-by: Chris Mason --- fs/btrfs/ioctl.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index f0b4237..04ece8f 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -2700,10 +2700,15 @@ static inline void lock_extent_range(struct inode *inode, u64 off, u64 len) lock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1); ordered = btrfs_lookup_first_ordered_extent(inode, off + len - 1); - if (!ordered && + if ((!ordered || + ordered->file_offset + ordered->len <= off || + ordered->file_offset >= off + len) && !test_range_bit(&BTRFS_I(inode)->io_tree, off, - off + len - 1, EXTENT_DELALLOC, 0, NULL)) + off + len - 1, EXTENT_DELALLOC, 0, NULL)) { + if (ordered) + btrfs_put_ordered_extent(ordered); break; + } unlock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1); if (ordered) btrfs_put_ordered_extent(ordered); -- 2.7.4