From bd6526d0df0f6be6426118f5f67f24273377a567 Mon Sep 17 00:00:00 2001 From: Filipe Manana Date: Tue, 15 Mar 2022 15:22:39 +0000 Subject: [PATCH] btrfs: lock the inode first before flushing range when punching hole When doing hole punching we are flushing delalloc and waiting for ordered extents to complete before locking the inode (VFS lock and the btrfs specific i_mmap_lock). This is fine because even if a write happens after we call btrfs_wait_ordered_range() and before we lock the inode (call btrfs_inode_lock()), we will notice the write at btrfs_punch_hole_lock_range() and flush delalloc and wait for its ordered extent. We can however make this simpler by locking first the inode an then call btrfs_wait_ordered_range(), which will allow us to remove the ordered extent lookup logic from btrfs_punch_hole_lock_range() in the next patch. It also makes the behaviour the same as plain fallocate, hole punching and reflinks. Signed-off-by: Filipe Manana Signed-off-by: David Sterba --- fs/btrfs/file.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index 0a9b334..f8eaa18 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -2976,11 +2976,12 @@ static int btrfs_punch_hole(struct file *file, loff_t offset, loff_t len) bool truncated_block = false; bool updated_inode = false; + btrfs_inode_lock(inode, BTRFS_ILOCK_MMAP); + ret = btrfs_wait_ordered_range(inode, offset, len); if (ret) - return ret; + goto out_only_mutex; - btrfs_inode_lock(inode, BTRFS_ILOCK_MMAP); ino_size = round_up(inode->i_size, fs_info->sectorsize); ret = find_first_non_hole(BTRFS_I(inode), &offset, &len); if (ret < 0) -- 2.7.4