vfs: get rid of old '->iterate' directory operation

All users now just use '->iterate_shared()', which only takes the
directory inode lock for reading.

Filesystems that never got convered to shared mode now instead use a
wrapper that drops the lock, re-takes it in write mode, calls the old
function, and then downgrades the lock back to read mode.

This way the VFS layer and other callers no longer need to care about
filesystems that never got converted to the modern era.

The filesystems that use the new wrapper are ceph, coda, exfat, jfs,
ntfs, ocfs2, overlayfs, and vboxsf.

Honestly, several of them look like they really could just iterate their
directories in shared mode and skip the wrapper entirely, but the point
of this change is to not change semantics or fix filesystems that
haven't been fixed in the last 7+ years, but to finally get rid of the
dual iterators.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

This commit is contained in:

Linus Torvalds

2023-08-05 12:25:01 -07:00

committed by

Christian Brauner

parent 0a2c2baafa

commit 3e32715496

13 changed files with 95 additions and 58 deletions

									
										fs/exportfs/expfs.c
									
		+1
		-1
	
												View File
												
				@@ -315,7 +315,7 @@ static int get_name(const struct path *path, char *name, struct dentry *child)

						goto out;

					error = -EINVAL;

					if (!file->f_op->iterate && !file->f_op->iterate_shared)

					if (!file->f_op->iterate_shared)

						goto out_close;

					buffer.sequence = 0;