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From:   Olga Kornievskaia <olga.kornievskaia@gmail.com>
To:     trond.myklebust@hammerspace.com, anna.schumaker@netapp.com
Cc:     linux-nfs@vger.kernel.org
Subject: [PATCH 1/1] NFSv4.2 fix handling of sr_eof in SEEK's reply
Date:   Wed, 31 Mar 2021 15:30:25 -0400
Message-Id: <20210331193025.25724-1-olga.kornievskaia@gmail.com>
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From: Olga Kornievskaia <kolga@netapp.com>

Currently the client ignores the value of the sr_eof of the SEEK
operation. According to the spec, if the server didn't find the
requested extent and reached the end of the file, the server
would return sr_eof=true. In case the request for DATA and no
data was found (ie in the middle of the hole), then the lseek
expects that ENXIO would be returned.

Fixes: 1c6dcbe5ceff8 ("NFS: Implement SEEK")
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
---
 fs/nfs/nfs42proc.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/fs/nfs/nfs42proc.c b/fs/nfs/nfs42proc.c
index 094024b0aca1..d359e712c11d 100644
--- a/fs/nfs/nfs42proc.c
+++ b/fs/nfs/nfs42proc.c
@@ -659,7 +659,10 @@ static loff_t _nfs42_proc_llseek(struct file *filep,
 	if (status)
 		return status;
 
-	return vfs_setpos(filep, res.sr_offset, inode->i_sb->s_maxbytes);
+	if (whence == SEEK_DATA && res.sr_eof)
+		return -NFS4ERR_NXIO;
+	else
+		return vfs_setpos(filep, res.sr_offset, inode->i_sb->s_maxbytes);
 }
 
 loff_t nfs42_proc_llseek(struct file *filep, loff_t offset, int whence)
-- 
2.18.2