NFS: Add method to detect whether an FSID is still on the server
Introduce a mechanism for probing a server to determine if an FSID
is present or absent.
The on-the-wire compound is different between minor version 0 and 1.
Minor version 0 appends a RENEW operation to identify which client
ID is probing. Minor version 1 has a SEQUENCE operation in the
compound which effectively carries the same information.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 1854b04..f903389 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -595,11 +595,13 @@
#define NFS4_enc_getattr_sz (compound_encode_hdr_maxsz + \
encode_sequence_maxsz + \
encode_putfh_maxsz + \
- encode_getattr_maxsz)
+ encode_getattr_maxsz + \
+ encode_renew_maxsz)
#define NFS4_dec_getattr_sz (compound_decode_hdr_maxsz + \
decode_sequence_maxsz + \
decode_putfh_maxsz + \
- decode_getattr_maxsz)
+ decode_getattr_maxsz + \
+ decode_renew_maxsz)
#define NFS4_enc_lookup_sz (compound_encode_hdr_maxsz + \
encode_sequence_maxsz + \
encode_putfh_maxsz + \
@@ -753,6 +755,18 @@
decode_sequence_maxsz + \
decode_putfh_maxsz + \
decode_secinfo_maxsz)
+#define NFS4_enc_fsid_present_sz \
+ (compound_encode_hdr_maxsz + \
+ encode_sequence_maxsz + \
+ encode_putfh_maxsz + \
+ encode_getfh_maxsz + \
+ encode_renew_maxsz)
+#define NFS4_dec_fsid_present_sz \
+ (compound_decode_hdr_maxsz + \
+ decode_sequence_maxsz + \
+ decode_putfh_maxsz + \
+ decode_getfh_maxsz + \
+ decode_renew_maxsz)
#if defined(CONFIG_NFS_V4_1)
#define NFS4_enc_bind_conn_to_session_sz \
(compound_encode_hdr_maxsz + \
@@ -2726,6 +2740,26 @@
encode_nops(&hdr);
}
+/*
+ * Encode FSID_PRESENT request
+ */
+static void nfs4_xdr_enc_fsid_present(struct rpc_rqst *req,
+ struct xdr_stream *xdr,
+ struct nfs4_fsid_present_arg *args)
+{
+ struct compound_hdr hdr = {
+ .minorversion = nfs4_xdr_minorversion(&args->seq_args),
+ };
+
+ encode_compound_hdr(xdr, req, &hdr);
+ encode_sequence(xdr, &args->seq_args, &hdr);
+ encode_putfh(xdr, args->fh, &hdr);
+ encode_getfh(xdr, &hdr);
+ if (args->renew)
+ encode_renew(xdr, args->clientid, &hdr);
+ encode_nops(&hdr);
+}
+
#if defined(CONFIG_NFS_V4_1)
/*
* BIND_CONN_TO_SESSION request
@@ -6883,6 +6917,34 @@
return status;
}
+/*
+ * Decode FSID_PRESENT response
+ */
+static int nfs4_xdr_dec_fsid_present(struct rpc_rqst *rqstp,
+ struct xdr_stream *xdr,
+ struct nfs4_fsid_present_res *res)
+{
+ struct compound_hdr hdr;
+ int status;
+
+ status = decode_compound_hdr(xdr, &hdr);
+ if (status)
+ goto out;
+ status = decode_sequence(xdr, &res->seq_res, rqstp);
+ if (status)
+ goto out;
+ status = decode_putfh(xdr);
+ if (status)
+ goto out;
+ status = decode_getfh(xdr, res->fh);
+ if (status)
+ goto out;
+ if (res->renew)
+ status = decode_renew(xdr);
+out:
+ return status;
+}
+
#if defined(CONFIG_NFS_V4_1)
/*
* Decode BIND_CONN_TO_SESSION response
@@ -7397,6 +7459,7 @@
PROC(FS_LOCATIONS, enc_fs_locations, dec_fs_locations),
PROC(RELEASE_LOCKOWNER, enc_release_lockowner, dec_release_lockowner),
PROC(SECINFO, enc_secinfo, dec_secinfo),
+ PROC(FSID_PRESENT, enc_fsid_present, dec_fsid_present),
#if defined(CONFIG_NFS_V4_1)
PROC(EXCHANGE_ID, enc_exchange_id, dec_exchange_id),
PROC(CREATE_SESSION, enc_create_session, dec_create_session),
