nfs41: Backchannel: CB_SEQUENCE validation
Validates the callback's sessionID, the slot number, and the sequence ID. Increments the slot's sequence. Detects replays, but simply prints a debug message (if debugging is enabled since we don't yet implement a duplicate request cache for the backchannel. This should not present a problem, since only idempotent callbacks are currently implemented. Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com> [nfs41: Backchannel: Be more obvious about the return value] [nfs41: Backchannel: dprink in host order] Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com>
This commit is contained in:
parent
963891ac43
commit
68f3f90133
|
@ -104,6 +104,57 @@ out:
|
|||
|
||||
#if defined(CONFIG_NFS_V4_1)
|
||||
|
||||
/*
|
||||
* Validate the sequenceID sent by the server.
|
||||
* Return success if the sequenceID is one more than what we last saw on
|
||||
* this slot, accounting for wraparound. Increments the slot's sequence.
|
||||
*
|
||||
* We don't yet implement a duplicate request cache, so at this time
|
||||
* we will log replays, and process them as if we had not seen them before,
|
||||
* but we don't bump the sequence in the slot. Not too worried about it,
|
||||
* since we only currently implement idempotent callbacks anyway.
|
||||
*
|
||||
* We have a single slot backchannel at this time, so we don't bother
|
||||
* checking the used_slots bit array on the table. The lower layer guarantees
|
||||
* a single outstanding callback request at a time.
|
||||
*/
|
||||
static int
|
||||
validate_seqid(struct nfs4_slot_table *tbl, u32 slotid, u32 seqid)
|
||||
{
|
||||
struct nfs4_slot *slot;
|
||||
|
||||
dprintk("%s enter. slotid %d seqid %d\n",
|
||||
__func__, slotid, seqid);
|
||||
|
||||
if (slotid > NFS41_BC_MAX_CALLBACKS)
|
||||
return htonl(NFS4ERR_BADSLOT);
|
||||
|
||||
slot = tbl->slots + slotid;
|
||||
dprintk("%s slot table seqid: %d\n", __func__, slot->seq_nr);
|
||||
|
||||
/* Normal */
|
||||
if (likely(seqid == slot->seq_nr + 1)) {
|
||||
slot->seq_nr++;
|
||||
return htonl(NFS4_OK);
|
||||
}
|
||||
|
||||
/* Replay */
|
||||
if (seqid == slot->seq_nr) {
|
||||
dprintk("%s seqid %d is a replay - no DRC available\n",
|
||||
__func__, seqid);
|
||||
return htonl(NFS4_OK);
|
||||
}
|
||||
|
||||
/* Wraparound */
|
||||
if (seqid == 1 && (slot->seq_nr + 1) == 0) {
|
||||
slot->seq_nr = 1;
|
||||
return htonl(NFS4_OK);
|
||||
}
|
||||
|
||||
/* Misordered request */
|
||||
return htonl(NFS4ERR_SEQ_MISORDERED);
|
||||
}
|
||||
|
||||
/*
|
||||
* Returns a pointer to a held 'struct nfs_client' that matches the server's
|
||||
* address, major version number, and session ID. It is the caller's
|
||||
|
@ -140,18 +191,27 @@ out:
|
|||
return NULL;
|
||||
}
|
||||
|
||||
/* FIXME: validate args->cbs_{sequence,slot}id */
|
||||
/* FIXME: referring calls should be processed */
|
||||
unsigned nfs4_callback_sequence(struct cb_sequenceargs *args,
|
||||
struct cb_sequenceres *res)
|
||||
{
|
||||
int i;
|
||||
unsigned status = 0;
|
||||
struct nfs_client *clp;
|
||||
int i, status;
|
||||
|
||||
for (i = 0; i < args->csa_nrclists; i++)
|
||||
kfree(args->csa_rclists[i].rcl_refcalls);
|
||||
kfree(args->csa_rclists);
|
||||
|
||||
status = htonl(NFS4ERR_BADSESSION);
|
||||
clp = find_client_with_session(args->csa_addr, 4, &args->csa_sessionid);
|
||||
if (clp == NULL)
|
||||
goto out;
|
||||
|
||||
status = validate_seqid(&clp->cl_session->bc_slot_table,
|
||||
args->csa_slotid, args->csa_sequenceid);
|
||||
if (status)
|
||||
goto out_putclient;
|
||||
|
||||
memcpy(&res->csr_sessionid, &args->csa_sessionid,
|
||||
sizeof(res->csr_sessionid));
|
||||
res->csr_sequenceid = args->csa_sequenceid;
|
||||
|
@ -159,9 +219,12 @@ unsigned nfs4_callback_sequence(struct cb_sequenceargs *args,
|
|||
res->csr_highestslotid = NFS41_BC_MAX_CALLBACKS - 1;
|
||||
res->csr_target_highestslotid = NFS41_BC_MAX_CALLBACKS - 1;
|
||||
|
||||
out_putclient:
|
||||
nfs_put_client(clp);
|
||||
out:
|
||||
dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
|
||||
res->csr_status = status;
|
||||
return status;
|
||||
return res->csr_status;
|
||||
}
|
||||
|
||||
#endif /* CONFIG_NFS_V4_1 */
|
||||
|
|
Loading…
Reference in a new issue