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	Wed, 13 Dec 2023 06:53:17 +0000
Date: Wed, 13 Dec 2023 06:53:16 +0000
From: Al Viro <viro@zeniv.linux.org.uk>
To: linux-fsdevel@vger.kernel.org
Cc: Evgeniy Dushistov <dushistov@mail.ru>,
	"Fabio M. De Francesco" <fmdefrancesco@gmail.com>,
	Matthew Wilcox <willy@infradead.org>
Subject: Re: [patches][cft] ufs stuff
Message-ID: <20231213065316.GK1674809@ZenIV>
References: <20231213031639.GJ1674809@ZenIV>
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Sender: Al Viro <viro@ftp.linux.org.uk>

On Wed, Dec 13, 2023 at 03:16:39AM +0000, Al Viro wrote:
> 	More old stuff, this time UFS one.  Part of that is
> yet another kmap_local_page() conversion, part - assorted
> cleanups.
> 	It seems to survive local beating, but it needs
> more review and testing.

Sigh...  That it does - especially since a bit more testing
has caught this (in mainline):

[PATCH] fix ufs_get_locked_folio() breakage

filemap_lock_folio() returns ERR_PTR(-ENOENT) if the thing is not
in cache - not NULL like find_lock_page() used to.

Fixes: 5fb7bd50b351 "ufs: add ufs_get_locked_folio and ufs_put_locked_folio"
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
diff --git a/fs/ufs/util.c b/fs/ufs/util.c
index 535c7ee80a10..f0e906ab4ddd 100644
--- a/fs/ufs/util.c
+++ b/fs/ufs/util.c
@@ -199,7 +199,7 @@ struct folio *ufs_get_locked_folio(struct address_space *mapping,
 {
 	struct inode *inode = mapping->host;
 	struct folio *folio = filemap_lock_folio(mapping, index);
-	if (!folio) {
+	if (IS_ERR(folio)) {
 		folio = read_mapping_folio(mapping, index, NULL);
 
 		if (IS_ERR(folio)) {