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From:   Scott Mayhew <smayhew@redhat.com>
To:     trond.myklebust@hammerspace.com, anna.schumaker@netapp.com
Cc:     linux-nfs@vger.kernel.org
Subject: [PATCH 1/2] nfs: ensure correct writeback errors are returned on close()
Date:   Fri, 31 Jul 2020 13:46:13 -0400
Message-Id: <20200731174614.1299346-2-smayhew@redhat.com>
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nfs_wb_all() calls filemap_write_and_wait(), which uses
filemap_check_errors() to determine the error to return.
filemap_check_errors() only looks at the mapping->flags and will
therefore only return either -ENOSPC or -EIO.  To ensure that the
correct error is returned on close(), nfs{,4}_file_flush() should call
file_check_and_advance_wb_err() which looks at the errseq value in
mapping->wb_err.

Fixes: 6fbda89b257f ("NFS: Replace custom error reporting mechanism with
generic one")
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
---
 fs/nfs/file.c     | 3 ++-
 fs/nfs/nfs4file.c | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/fs/nfs/file.c b/fs/nfs/file.c
index f96367a2463e..eeef6580052f 100644
--- a/fs/nfs/file.c
+++ b/fs/nfs/file.c
@@ -148,7 +148,8 @@ nfs_file_flush(struct file *file, fl_owner_t id)
 		return 0;
 
 	/* Flush writes to the server and return any errors */
-	return nfs_wb_all(inode);
+	nfs_wb_all(inode);
+	return file_check_and_advance_wb_err(file);
 }
 
 ssize_t
diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c
index 8e5d6223ddd3..77bf9c12734c 100644
--- a/fs/nfs/nfs4file.c
+++ b/fs/nfs/nfs4file.c
@@ -125,7 +125,8 @@ nfs4_file_flush(struct file *file, fl_owner_t id)
 		return filemap_fdatawrite(file->f_mapping);
 
 	/* Flush writes to the server and return any errors */
-	return nfs_wb_all(inode);
+	nfs_wb_all(inode);
+	return file_check_and_advance_wb_err(file);
 }
 
 #ifdef CONFIG_NFS_V4_2
-- 
2.25.4