From: Qinghua Jin <qhjin.dev@xxxxxxxxx> Subject: minix: fix bug when opening a file with O_DIRECT Testcase: 1. create a minix file system and mount it 2. open a file on the file system with O_RDWR|O_CREAT|O_TRUNC|O_DIRECT 3. open fails with -EINVAL but leaves an empty file behind. All other open() failures don't leave the failed open files behind. It is hard to check the direct_IO op before creating the inode. Just as ext4 and btrfs do, this patch will resolve the issue by allowing to create the file with O_DIRECT but returning error when writing the file. Link: https://lkml.kernel.org/r/20220107133626.413379-1-qhjin.dev@xxxxxxxxx Signed-off-by: Qinghua Jin <qhjin.dev@xxxxxxxxx> Reported-by: Colin Ian King <colin.king@xxxxxxxxx> Reviewed-by: Jan Kara <jack@xxxxxxx> Acked-by: Christian Brauner <christian.brauner@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/minix/inode.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/fs/minix/inode.c~minix-fix-bug-when-opening-a-file-with-o_direct +++ a/fs/minix/inode.c @@ -447,7 +447,8 @@ static const struct address_space_operat .writepage = minix_writepage, .write_begin = minix_write_begin, .write_end = generic_write_end, - .bmap = minix_bmap + .bmap = minix_bmap, + .direct_IO = noop_direct_IO }; static const struct inode_operations minix_symlink_inode_operations = { _