Change calling conventions for filldir_t

filldir_t instances (directory iterators callbacks) used to return 0 for
"OK, keep going" or -E... for "stop".  Note that it's *NOT* how the
error values are reported - the rules for those are callback-dependent
and ->iterate{,_shared}() instances only care about zero vs. non-zero
(look at emit_dir() and friends).

So let's just return bool ("should we keep going?") - it's less confusing
that way.  The choice between "true means keep going" and "true means
stop" is bikesheddable; we have two groups of callbacks -
	do something for everything in directory, until we run into problem
and
	find an entry in directory and do something to it.

The former tended to use 0/-E... conventions - -E<something> on failure.
The latter tended to use 0/1, 1 being "stop, we are done".
The callers treated anything non-zero as "stop", ignoring which
non-zero value did they get.

"true means stop" would be more natural for the second group; "true
means keep going" - for the first one.  I tried both variants and
the things like
	if allocation failed
		something = -ENOMEM;
		return true;
just looked unnatural and asking for trouble.

[folded suggestion from Matthew Wilcox <willy@infradead.org>]
Acked-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 2 insertions, 2 deletions

diff --git a/fs/xfs/scrub/parent.c b/fs/xfs/scrub/parent.c
index ab182a5cd0c0..d8dff3fd8053 100644
--- a/fs/xfs/scrub/parent.c
+++ b/fs/xfs/scrub/parent.c
@@ -38,7 +38,7 @@ struct xchk_parent_ctx {
 };
 
 /* Look for a single entry in a directory pointing to an inode. */
-STATIC int
+STATIC bool
 xchk_parent_actor(
 	struct dir_context	*dc,
 	const char		*name,
@@ -62,7 +62,7 @@ xchk_parent_actor(
 	if (xchk_should_terminate(spc->sc, &error))
 		spc->cancelled = true;
 
-	return error;
+	return !error;
 }
 
 /* Count the number of dentries in the parent dir that point to this inode. */