2 * linux/fs/nfs/callback_proc.c
4 * Copyright (C) 2004 Trond Myklebust
6 * NFSv4 callback procedures
8 #include <linux/nfs4.h>
9 #include <linux/nfs_fs.h>
10 #include <linux/slab.h>
13 #include "delegation.h"
17 #define NFSDBG_FACILITY NFSDBG_CALLBACK
20 __be32 nfs4_callback_getattr(struct cb_getattrargs *args, struct cb_getattrres *res)
22 struct nfs_client *clp;
23 struct nfs_delegation *delegation;
24 struct nfs_inode *nfsi;
27 res->bitmap[0] = res->bitmap[1] = 0;
28 res->status = htonl(NFS4ERR_BADHANDLE);
29 clp = nfs_find_client(args->addr, 4);
33 dprintk("NFS: GETATTR callback request from %s\n",
34 rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));
36 inode = nfs_delegation_find_inode(clp, &args->fh);
41 delegation = rcu_dereference(nfsi->delegation);
42 if (delegation == NULL || (delegation->type & FMODE_WRITE) == 0)
44 res->size = i_size_read(inode);
45 res->change_attr = delegation->change_attr;
46 if (nfsi->npages != 0)
48 res->ctime = inode->i_ctime;
49 res->mtime = inode->i_mtime;
50 res->bitmap[0] = (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE) &
52 res->bitmap[1] = (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY) &
61 dprintk("%s: exit with status = %d\n", __func__, ntohl(res->status));
65 __be32 nfs4_callback_recall(struct cb_recallargs *args, void *dummy)
67 struct nfs_client *clp;
71 res = htonl(NFS4ERR_BADHANDLE);
72 clp = nfs_find_client(args->addr, 4);
76 dprintk("NFS: RECALL callback request from %s\n",
77 rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));
80 struct nfs_client *prev = clp;
82 inode = nfs_delegation_find_inode(clp, &args->fh);
84 /* Set up a helper thread to actually return the delegation */
85 switch (nfs_async_inode_return_delegation(inode, &args->stateid)) {
91 res = htonl(NFS4ERR_BAD_STATEID);
94 res = htonl(NFS4ERR_RESOURCE);
98 clp = nfs_find_client_next(prev);
100 } while (clp != NULL);
102 dprintk("%s: exit with status = %d\n", __func__, ntohl(res));
106 int nfs4_validate_delegation_stateid(struct nfs_delegation *delegation, const nfs4_stateid *stateid)
108 if (delegation == NULL || memcmp(delegation->stateid.data, stateid->data,
109 sizeof(delegation->stateid.data)) != 0)
114 #if defined(CONFIG_NFS_V4_1)
116 int nfs41_validate_delegation_stateid(struct nfs_delegation *delegation, const nfs4_stateid *stateid)
118 if (delegation == NULL)
121 if (stateid->stateid.seqid != 0)
123 if (memcmp(&delegation->stateid.stateid.other,
124 &stateid->stateid.other,
125 NFS4_STATEID_OTHER_SIZE))
132 * Validate the sequenceID sent by the server.
133 * Return success if the sequenceID is one more than what we last saw on
134 * this slot, accounting for wraparound. Increments the slot's sequence.
136 * We don't yet implement a duplicate request cache, instead we set the
137 * back channel ca_maxresponsesize_cached to zero. This is OK for now
138 * since we only currently implement idempotent callbacks anyway.
140 * We have a single slot backchannel at this time, so we don't bother
141 * checking the used_slots bit array on the table. The lower layer guarantees
142 * a single outstanding callback request at a time.
145 validate_seqid(struct nfs4_slot_table *tbl, struct cb_sequenceargs * args)
147 struct nfs4_slot *slot;
149 dprintk("%s enter. slotid %d seqid %d\n",
150 __func__, args->csa_slotid, args->csa_sequenceid);
152 if (args->csa_slotid > NFS41_BC_MAX_CALLBACKS)
153 return htonl(NFS4ERR_BADSLOT);
155 slot = tbl->slots + args->csa_slotid;
156 dprintk("%s slot table seqid: %d\n", __func__, slot->seq_nr);
159 if (likely(args->csa_sequenceid == slot->seq_nr + 1)) {
161 return htonl(NFS4_OK);
165 if (args->csa_sequenceid == slot->seq_nr) {
166 dprintk("%s seqid %d is a replay\n",
167 __func__, args->csa_sequenceid);
168 /* Signal process_op to set this error on next op */
169 if (args->csa_cachethis == 0)
170 return htonl(NFS4ERR_RETRY_UNCACHED_REP);
172 /* The ca_maxresponsesize_cached is 0 with no DRC */
173 else if (args->csa_cachethis == 1)
174 return htonl(NFS4ERR_REP_TOO_BIG_TO_CACHE);
178 if (args->csa_sequenceid == 1 && (slot->seq_nr + 1) == 0) {
180 return htonl(NFS4_OK);
183 /* Misordered request */
184 return htonl(NFS4ERR_SEQ_MISORDERED);
188 * Returns a pointer to a held 'struct nfs_client' that matches the server's
189 * address, major version number, and session ID. It is the caller's
190 * responsibility to release the returned reference.
192 * Returns NULL if there are no connections with sessions, or if no session
193 * matches the one of interest.
195 static struct nfs_client *find_client_with_session(
196 const struct sockaddr *addr, u32 nfsversion,
197 struct nfs4_sessionid *sessionid)
199 struct nfs_client *clp;
201 clp = nfs_find_client(addr, 4);
206 struct nfs_client *prev = clp;
208 if (clp->cl_session != NULL) {
209 if (memcmp(clp->cl_session->sess_id.data,
211 NFS4_MAX_SESSIONID_LEN) == 0) {
212 /* Returns a held reference to clp */
216 clp = nfs_find_client_next(prev);
217 nfs_put_client(prev);
218 } while (clp != NULL);
224 * For each referring call triple, check the session's slot table for
225 * a match. If the slot is in use and the sequence numbers match, the
226 * client is still waiting for a response to the original request.
228 static bool referring_call_exists(struct nfs_client *clp,
230 struct referring_call_list *rclists)
234 struct nfs4_session *session;
235 struct nfs4_slot_table *tbl;
236 struct referring_call_list *rclist;
237 struct referring_call *ref;
240 * XXX When client trunking is implemented, this becomes
241 * a session lookup from within the loop
243 session = clp->cl_session;
244 tbl = &session->fc_slot_table;
246 for (i = 0; i < nrclists; i++) {
247 rclist = &rclists[i];
248 if (memcmp(session->sess_id.data,
249 rclist->rcl_sessionid.data,
250 NFS4_MAX_SESSIONID_LEN) != 0)
253 for (j = 0; j < rclist->rcl_nrefcalls; j++) {
254 ref = &rclist->rcl_refcalls[j];
256 dprintk("%s: sessionid %x:%x:%x:%x sequenceid %u "
257 "slotid %u\n", __func__,
258 ((u32 *)&rclist->rcl_sessionid.data)[0],
259 ((u32 *)&rclist->rcl_sessionid.data)[1],
260 ((u32 *)&rclist->rcl_sessionid.data)[2],
261 ((u32 *)&rclist->rcl_sessionid.data)[3],
262 ref->rc_sequenceid, ref->rc_slotid);
264 spin_lock(&tbl->slot_tbl_lock);
265 status = (test_bit(ref->rc_slotid, tbl->used_slots) &&
266 tbl->slots[ref->rc_slotid].seq_nr ==
268 spin_unlock(&tbl->slot_tbl_lock);
278 __be32 nfs4_callback_sequence(struct cb_sequenceargs *args,
279 struct cb_sequenceres *res)
281 struct nfs_client *clp;
285 status = htonl(NFS4ERR_BADSESSION);
286 clp = find_client_with_session(args->csa_addr, 4, &args->csa_sessionid);
290 status = validate_seqid(&clp->cl_session->bc_slot_table, args);
295 * Check for pending referring calls. If a match is found, a
296 * related callback was received before the response to the original
299 if (referring_call_exists(clp, args->csa_nrclists, args->csa_rclists)) {
300 status = htonl(NFS4ERR_DELAY);
304 memcpy(&res->csr_sessionid, &args->csa_sessionid,
305 sizeof(res->csr_sessionid));
306 res->csr_sequenceid = args->csa_sequenceid;
307 res->csr_slotid = args->csa_slotid;
308 res->csr_highestslotid = NFS41_BC_MAX_CALLBACKS - 1;
309 res->csr_target_highestslotid = NFS41_BC_MAX_CALLBACKS - 1;
314 for (i = 0; i < args->csa_nrclists; i++)
315 kfree(args->csa_rclists[i].rcl_refcalls);
316 kfree(args->csa_rclists);
318 if (status == htonl(NFS4ERR_RETRY_UNCACHED_REP))
321 res->csr_status = status;
322 dprintk("%s: exit with status = %d res->csr_status %d\n", __func__,
323 ntohl(status), ntohl(res->csr_status));
327 __be32 nfs4_callback_recallany(struct cb_recallanyargs *args, void *dummy)
329 struct nfs_client *clp;
333 status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
334 clp = nfs_find_client(args->craa_addr, 4);
338 dprintk("NFS: RECALL_ANY callback request from %s\n",
339 rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));
341 if (test_bit(RCA4_TYPE_MASK_RDATA_DLG, (const unsigned long *)
342 &args->craa_type_mask))
344 if (test_bit(RCA4_TYPE_MASK_WDATA_DLG, (const unsigned long *)
345 &args->craa_type_mask))
346 flags |= FMODE_WRITE;
349 nfs_expire_all_delegation_types(clp, flags);
350 status = htonl(NFS4_OK);
352 dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
356 /* Reduce the fore channel's max_slots to the target value */
357 __be32 nfs4_callback_recallslot(struct cb_recallslotargs *args, void *dummy)
359 struct nfs_client *clp;
360 struct nfs4_slot_table *fc_tbl;
363 status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
364 clp = nfs_find_client(args->crsa_addr, 4);
368 dprintk("NFS: CB_RECALL_SLOT request from %s target max slots %d\n",
369 rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR),
370 args->crsa_target_max_slots);
372 fc_tbl = &clp->cl_session->fc_slot_table;
374 status = htonl(NFS4ERR_BAD_HIGH_SLOT);
375 if (args->crsa_target_max_slots > fc_tbl->max_slots ||
376 args->crsa_target_max_slots < 1)
379 status = htonl(NFS4_OK);
380 if (args->crsa_target_max_slots == fc_tbl->max_slots)
383 fc_tbl->target_max_slots = args->crsa_target_max_slots;
384 nfs41_handle_recall_slot(clp);
386 nfs_put_client(clp); /* balance nfs_find_client */
388 dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
391 #endif /* CONFIG_NFS_V4_1 */