[PATCH v2] Revert "fs/ntfs3: Replace inode_trylock with inode_lock"

[Konstantin Komarov]

This reverts commit 69505fe98f198ee813898cbcaf6770949636430b.

Initially, conditional lock acquisition was removed to fix an xfstest bug
that was observed during internal testing. The deadlock reported by syzbot
is resolved by reintroducing conditional acquisition. The xfstest bug no
longer occurs on kernel version 6.16-rc1 during internal testing. I
assume that changes in other modules may have contributed to this.

Fixes: 69505fe98f19 ("fs/ntfs3: Replace inode_trylock with inode_lock")
Reported-by: syzbot+a91fcdbd2698f99db8f4@xxxxxxxxxxxxxxxxxxxxxxxxx
Suggested-by: Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@xxxxxxxxxxxxxxxxxxxx>
---
 fs/ntfs3/file.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/fs/ntfs3/file.c b/fs/ntfs3/file.c
index 65fb27d1e17c..2e321b84a1ed 100644
--- a/fs/ntfs3/file.c
+++ b/fs/ntfs3/file.c
@@ -322,7 +322,10 @@ static int ntfs_file_mmap(struct file *file, struct vm_area_struct *vma)
 		}
 
 		if (ni->i_valid < to) {
-			inode_lock(inode);
+			if (!inode_trylock(inode)) {
+				err = -EAGAIN;
+				goto out;
+			}
 			err = ntfs_extend_initialized_size(file, ni,
 							   ni->i_valid, to);
 			inode_unlock(inode);
-- 
2.43.0