[PATCH 5.15 602/913] NFS: Use of mapping_set_error() results in spurious errors

From: Greg Kroah-Hartman
Date: Tue Apr 05 2022 - 18:49:03 EST


From: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>

[ Upstream commit 6c984083ec2453dfd3fcf98f392f34500c73e3f2 ]

The use of mapping_set_error() in conjunction with calls to
filemap_check_errors() is problematic because every error gets reported
as either an EIO or an ENOSPC by filemap_check_errors() in functions
such as filemap_write_and_wait() or filemap_write_and_wait_range().
In almost all cases, we prefer to use the more nuanced wb errors.

Fixes: b8946d7bfb94 ("NFS: Revalidate the file mapping on all fatal writeback errors")
Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/nfs/write.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 7dce3e735fc5..0691b0b02147 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -314,7 +314,10 @@ static void nfs_mapping_set_error(struct page *page, int error)
struct address_space *mapping = page_file_mapping(page);

SetPageError(page);
- mapping_set_error(mapping, error);
+ filemap_set_wb_err(mapping, error);
+ if (mapping->host)
+ errseq_set(&mapping->host->i_sb->s_wb_err,
+ error == -ENOSPC ? -ENOSPC : -EIO);
nfs_set_pageerror(mapping);
}

--
2.34.1