From 2c3f49b614e82ae37b0d9e8704e16c4a8c3b7fee Mon Sep 17 00:00:00 2001
From: "Darrick J. Wong" <djwong@kernel.org>
Date: Tue, 10 Aug 2021 18:32:55 -0700
Subject: [PATCH] iomap: pass writeback errors to the mapping
Git-commit: b69eea82d37d9ee7cfb3bf05103549dd4ed5ffc3
Patch-mainline: v5.15-rc1
References: stable-5.14.6

[ Upstream commit b69eea82d37d9ee7cfb3bf05103549dd4ed5ffc3 ]

Modern-day mapping_set_error has the ability to squash the usual
negative error code into something appropriate for long-term storage in
a struct address_space -- ENOSPC becomes AS_ENOSPC, and everything else
becomes EIO.  iomap squashes /everything/ to EIO, just as XFS did before
that, but this doesn't make sense.

Fix this by making it so that we can pass ENOSPC to userspace when
writeback fails due to space problems.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 fs/iomap/buffered-io.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index 87ccb3438bec..b06138c6190b 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -1016,7 +1016,7 @@ iomap_finish_page_writeback(struct inode *inode, struct page *page,
 
 	if (error) {
 		SetPageError(page);
-		mapping_set_error(inode->i_mapping, -EIO);
+		mapping_set_error(inode->i_mapping, error);
 	}
 
 	WARN_ON_ONCE(i_blocks_per_page(inode, page) > 1 && !iop);
-- 
2.26.2