Since commit:
[0e0cb35] NFSv4: Handle NFS4ERR_OLD_STATEID in CLOSE/OPEN_DOWNGRADE
xfstests generic/168 on v4.2 starts to fail because reflink call gets:
+XFS_IOC_CLONE_RANGE: Resource temporarily unavailable
In tshark output, NFS4ERR_OLD_STATEID stands out when comparing with
good ones:
5210 NFS 406 V4 Reply (Call In 5209) OPEN StateID: 0xadb5
5211 NFS 314 V4 Call GETATTR FH: 0x8d44a6b1
5212 NFS 250 V4 Reply (Call In 5211) GETATTR
5213 NFS 314 V4 Call GETATTR FH: 0x8d44a6b1
5214 NFS 250 V4 Reply (Call In 5213) GETATTR
5216 NFS 422 V4 Call WRITE StateID: 0xa818 Offset: 851968 Len: 65536
5218 NFS 266 V4 Reply (Call In 5216) WRITE
5219 NFS 382 V4 Call OPEN DH: 0x8d44a6b1/
5220 NFS 338 V4 Call CLOSE StateID: 0xadb5
5222 NFS 406 V4 Reply (Call In 5219) OPEN StateID: 0xa342
5223 NFS 250 V4 Reply (Call In 5220) CLOSE Status: NFS4ERR_OLD_STATEID
5225 NFS 338 V4 Call CLOSE StateID: 0xa342
5226 NFS 314 V4 Call GETATTR FH: 0x8d44a6b1
5227 NFS 266 V4 Reply (Call In 5225) CLOSE
5228 NFS 250 V4 Reply (Call In 5226) GETATTR
It's easy to reproduce. By printing some logs, found that we are making
CLOSE seqid larger then OPEN seqid when racing.
Fix this by not bumping seqid when it's equal to OPEN seqid. Also
put the whole changing process into seqlock read protection in case
really bad luck, and this is the same locking behavior with the
old deleted function.
Fixes: 0e0cb35b417f ("NFSv4: Handle NFS4ERR_OLD_STATEID in CLOSE/OPEN_DOWNGRADE")
Signed-off-by: Murphy Zhou <jencce.kernel@xxxxxxxxx>
---
fs/nfs/nfs4proc.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 11eafcf..6db5a09 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -3334,12 +3334,13 @@ static void nfs4_sync_open_stateid(nfs4_stateid *dst,
break;
}
seqid_open = state->open_stateid.seqid;
- if (read_seqretry(&state->seqlock, seq))
- continue;
dst_seqid = be32_to_cpu(dst->seqid);
if ((s32)(dst_seqid - be32_to_cpu(seqid_open)) < 0)
dst->seqid = seqid_open;
+
+ if (read_seqretry(&state->seqlock, seq))
+ continue;
break;
}
}
@@ -3367,14 +3368,16 @@ static bool nfs4_refresh_open_old_stateid(nfs4_stateid *dst,
break;
}
seqid_open = state->open_stateid.seqid;
- if (read_seqretry(&state->seqlock, seq))
- continue;
dst_seqid = be32_to_cpu(dst->seqid);
- if ((s32)(dst_seqid - be32_to_cpu(seqid_open)) >= 0)
+ if ((s32)(dst_seqid - be32_to_cpu(seqid_open)) > 0)
dst->seqid = cpu_to_be32(dst_seqid + 1);
else
dst->seqid = seqid_open;
+
+ if (read_seqretry(&state->seqlock, seq))
+ continue;
+
ret = true;
break;
}
--
1.8.3.1
