mm: fix exec activate_mm vs TLB shootdown and lazy tlb switching race
[linux/fpc-iii.git] / fs / nfs / nfs4client.c
blob0924b68b56574e6eedd993b7a8361f7cac798c0f
1 /*
2 * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
3 * Written by David Howells (dhowells@redhat.com)
4 */
5 #include <linux/module.h>
6 #include <linux/nfs_fs.h>
7 #include <linux/nfs_mount.h>
8 #include <linux/sunrpc/addr.h>
9 #include <linux/sunrpc/auth.h>
10 #include <linux/sunrpc/xprt.h>
11 #include <linux/sunrpc/bc_xprt.h>
12 #include <linux/sunrpc/rpc_pipe_fs.h>
13 #include "internal.h"
14 #include "callback.h"
15 #include "delegation.h"
16 #include "nfs4session.h"
17 #include "nfs4idmap.h"
18 #include "pnfs.h"
19 #include "netns.h"
21 #define NFSDBG_FACILITY NFSDBG_CLIENT
24 * Get a unique NFSv4.0 callback identifier which will be used
25 * by the V4.0 callback service to lookup the nfs_client struct
27 static int nfs_get_cb_ident_idr(struct nfs_client *clp, int minorversion)
29 int ret = 0;
30 struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
32 if (clp->rpc_ops->version != 4 || minorversion != 0)
33 return ret;
34 idr_preload(GFP_KERNEL);
35 spin_lock(&nn->nfs_client_lock);
36 ret = idr_alloc(&nn->cb_ident_idr, clp, 1, 0, GFP_NOWAIT);
37 if (ret >= 0)
38 clp->cl_cb_ident = ret;
39 spin_unlock(&nn->nfs_client_lock);
40 idr_preload_end();
41 return ret < 0 ? ret : 0;
44 #ifdef CONFIG_NFS_V4_1
45 /**
46 * Per auth flavor data server rpc clients
48 struct nfs4_ds_server {
49 struct list_head list; /* ds_clp->cl_ds_clients */
50 struct rpc_clnt *rpc_clnt;
53 /**
54 * Common lookup case for DS I/O
56 static struct nfs4_ds_server *
57 nfs4_find_ds_client(struct nfs_client *ds_clp, rpc_authflavor_t flavor)
59 struct nfs4_ds_server *dss;
61 rcu_read_lock();
62 list_for_each_entry_rcu(dss, &ds_clp->cl_ds_clients, list) {
63 if (dss->rpc_clnt->cl_auth->au_flavor != flavor)
64 continue;
65 goto out;
67 dss = NULL;
68 out:
69 rcu_read_unlock();
70 return dss;
73 static struct nfs4_ds_server *
74 nfs4_add_ds_client(struct nfs_client *ds_clp, rpc_authflavor_t flavor,
75 struct nfs4_ds_server *new)
77 struct nfs4_ds_server *dss;
79 spin_lock(&ds_clp->cl_lock);
80 list_for_each_entry(dss, &ds_clp->cl_ds_clients, list) {
81 if (dss->rpc_clnt->cl_auth->au_flavor != flavor)
82 continue;
83 goto out;
85 if (new)
86 list_add_rcu(&new->list, &ds_clp->cl_ds_clients);
87 dss = new;
88 out:
89 spin_unlock(&ds_clp->cl_lock); /* need some lock to protect list */
90 return dss;
93 static struct nfs4_ds_server *
94 nfs4_alloc_ds_server(struct nfs_client *ds_clp, rpc_authflavor_t flavor)
96 struct nfs4_ds_server *dss;
98 dss = kmalloc(sizeof(*dss), GFP_NOFS);
99 if (dss == NULL)
100 return ERR_PTR(-ENOMEM);
102 dss->rpc_clnt = rpc_clone_client_set_auth(ds_clp->cl_rpcclient, flavor);
103 if (IS_ERR(dss->rpc_clnt)) {
104 int err = PTR_ERR(dss->rpc_clnt);
105 kfree (dss);
106 return ERR_PTR(err);
108 INIT_LIST_HEAD(&dss->list);
110 return dss;
113 static void
114 nfs4_free_ds_server(struct nfs4_ds_server *dss)
116 rpc_release_client(dss->rpc_clnt);
117 kfree(dss);
121 * Find or create a DS rpc client with th MDS server rpc client auth flavor
122 * in the nfs_client cl_ds_clients list.
124 struct rpc_clnt *
125 nfs4_find_or_create_ds_client(struct nfs_client *ds_clp, struct inode *inode)
127 struct nfs4_ds_server *dss, *new;
128 rpc_authflavor_t flavor = NFS_SERVER(inode)->client->cl_auth->au_flavor;
130 dss = nfs4_find_ds_client(ds_clp, flavor);
131 if (dss != NULL)
132 goto out;
133 new = nfs4_alloc_ds_server(ds_clp, flavor);
134 if (IS_ERR(new))
135 return ERR_CAST(new);
136 dss = nfs4_add_ds_client(ds_clp, flavor, new);
137 if (dss != new)
138 nfs4_free_ds_server(new);
139 out:
140 return dss->rpc_clnt;
142 EXPORT_SYMBOL_GPL(nfs4_find_or_create_ds_client);
144 static void
145 nfs4_shutdown_ds_clients(struct nfs_client *clp)
147 struct nfs4_ds_server *dss;
148 LIST_HEAD(shutdown_list);
150 while (!list_empty(&clp->cl_ds_clients)) {
151 dss = list_entry(clp->cl_ds_clients.next,
152 struct nfs4_ds_server, list);
153 list_del(&dss->list);
154 rpc_shutdown_client(dss->rpc_clnt);
155 kfree (dss);
159 void nfs41_shutdown_client(struct nfs_client *clp)
161 if (nfs4_has_session(clp)) {
162 nfs4_shutdown_ds_clients(clp);
163 nfs4_destroy_session(clp->cl_session);
164 nfs4_destroy_clientid(clp);
168 #endif /* CONFIG_NFS_V4_1 */
170 void nfs40_shutdown_client(struct nfs_client *clp)
172 if (clp->cl_slot_tbl) {
173 nfs4_shutdown_slot_table(clp->cl_slot_tbl);
174 kfree(clp->cl_slot_tbl);
178 struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *cl_init)
180 int err;
181 struct nfs_client *clp = nfs_alloc_client(cl_init);
182 if (IS_ERR(clp))
183 return clp;
185 err = nfs_get_cb_ident_idr(clp, cl_init->minorversion);
186 if (err)
187 goto error;
189 if (cl_init->minorversion > NFS4_MAX_MINOR_VERSION) {
190 err = -EINVAL;
191 goto error;
194 spin_lock_init(&clp->cl_lock);
195 INIT_DELAYED_WORK(&clp->cl_renewd, nfs4_renew_state);
196 INIT_LIST_HEAD(&clp->cl_ds_clients);
197 rpc_init_wait_queue(&clp->cl_rpcwaitq, "NFS client");
198 clp->cl_state = 1 << NFS4CLNT_LEASE_EXPIRED;
199 clp->cl_minorversion = cl_init->minorversion;
200 clp->cl_mvops = nfs_v4_minor_ops[cl_init->minorversion];
201 clp->cl_mig_gen = 1;
202 #if IS_ENABLED(CONFIG_NFS_V4_1)
203 init_waitqueue_head(&clp->cl_lock_waitq);
204 #endif
205 return clp;
207 error:
208 nfs_free_client(clp);
209 return ERR_PTR(err);
213 * Destroy the NFS4 callback service
215 static void nfs4_destroy_callback(struct nfs_client *clp)
217 if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
218 nfs_callback_down(clp->cl_mvops->minor_version, clp->cl_net);
221 static void nfs4_shutdown_client(struct nfs_client *clp)
223 if (__test_and_clear_bit(NFS_CS_RENEWD, &clp->cl_res_state))
224 nfs4_kill_renewd(clp);
225 clp->cl_mvops->shutdown_client(clp);
226 nfs4_destroy_callback(clp);
227 if (__test_and_clear_bit(NFS_CS_IDMAP, &clp->cl_res_state))
228 nfs_idmap_delete(clp);
230 rpc_destroy_wait_queue(&clp->cl_rpcwaitq);
231 kfree(clp->cl_serverowner);
232 kfree(clp->cl_serverscope);
233 kfree(clp->cl_implid);
234 kfree(clp->cl_owner_id);
237 void nfs4_free_client(struct nfs_client *clp)
239 nfs4_shutdown_client(clp);
240 nfs_free_client(clp);
244 * Initialize the NFS4 callback service
246 static int nfs4_init_callback(struct nfs_client *clp)
248 struct rpc_xprt *xprt;
249 int error;
251 xprt = rcu_dereference_raw(clp->cl_rpcclient->cl_xprt);
253 if (nfs4_has_session(clp)) {
254 error = xprt_setup_backchannel(xprt, NFS41_BC_MIN_CALLBACKS);
255 if (error < 0)
256 return error;
259 error = nfs_callback_up(clp->cl_mvops->minor_version, xprt);
260 if (error < 0) {
261 dprintk("%s: failed to start callback. Error = %d\n",
262 __func__, error);
263 return error;
265 __set_bit(NFS_CS_CALLBACK, &clp->cl_res_state);
267 return 0;
271 * nfs40_init_client - nfs_client initialization tasks for NFSv4.0
272 * @clp - nfs_client to initialize
274 * Returns zero on success, or a negative errno if some error occurred.
276 int nfs40_init_client(struct nfs_client *clp)
278 struct nfs4_slot_table *tbl;
279 int ret;
281 tbl = kzalloc(sizeof(*tbl), GFP_NOFS);
282 if (tbl == NULL)
283 return -ENOMEM;
285 ret = nfs4_setup_slot_table(tbl, NFS4_MAX_SLOT_TABLE,
286 "NFSv4.0 transport Slot table");
287 if (ret) {
288 kfree(tbl);
289 return ret;
292 clp->cl_slot_tbl = tbl;
293 return 0;
296 #if defined(CONFIG_NFS_V4_1)
299 * nfs41_init_client - nfs_client initialization tasks for NFSv4.1+
300 * @clp - nfs_client to initialize
302 * Returns zero on success, or a negative errno if some error occurred.
304 int nfs41_init_client(struct nfs_client *clp)
306 struct nfs4_session *session = NULL;
309 * Create the session and mark it expired.
310 * When a SEQUENCE operation encounters the expired session
311 * it will do session recovery to initialize it.
313 session = nfs4_alloc_session(clp);
314 if (!session)
315 return -ENOMEM;
317 clp->cl_session = session;
320 * The create session reply races with the server back
321 * channel probe. Mark the client NFS_CS_SESSION_INITING
322 * so that the client back channel can find the
323 * nfs_client struct
325 nfs_mark_client_ready(clp, NFS_CS_SESSION_INITING);
326 return 0;
329 #endif /* CONFIG_NFS_V4_1 */
332 * Initialize the minor version specific parts of an NFS4 client record
334 static int nfs4_init_client_minor_version(struct nfs_client *clp)
336 int ret;
338 ret = clp->cl_mvops->init_client(clp);
339 if (ret)
340 return ret;
341 return nfs4_init_callback(clp);
345 * nfs4_init_client - Initialise an NFS4 client record
347 * @clp: nfs_client to initialise
348 * @timeparms: timeout parameters for underlying RPC transport
349 * @ip_addr: callback IP address in presentation format
350 * @authflavor: authentication flavor for underlying RPC transport
352 * Returns pointer to an NFS client, or an ERR_PTR value.
354 struct nfs_client *nfs4_init_client(struct nfs_client *clp,
355 const struct nfs_client_initdata *cl_init)
357 char buf[INET6_ADDRSTRLEN + 1];
358 const char *ip_addr = cl_init->ip_addr;
359 struct nfs_client *old;
360 int error;
362 if (clp->cl_cons_state == NFS_CS_READY)
363 /* the client is initialised already */
364 return clp;
366 /* Check NFS protocol revision and initialize RPC op vector */
367 clp->rpc_ops = &nfs_v4_clientops;
369 if (clp->cl_minorversion != 0)
370 __set_bit(NFS_CS_INFINITE_SLOTS, &clp->cl_flags);
371 __set_bit(NFS_CS_DISCRTRY, &clp->cl_flags);
372 __set_bit(NFS_CS_NO_RETRANS_TIMEOUT, &clp->cl_flags);
374 error = nfs_create_rpc_client(clp, cl_init, RPC_AUTH_GSS_KRB5I);
375 if (error == -EINVAL)
376 error = nfs_create_rpc_client(clp, cl_init, RPC_AUTH_UNIX);
377 if (error < 0)
378 goto error;
380 /* If no clientaddr= option was specified, find a usable cb address */
381 if (ip_addr == NULL) {
382 struct sockaddr_storage cb_addr;
383 struct sockaddr *sap = (struct sockaddr *)&cb_addr;
385 error = rpc_localaddr(clp->cl_rpcclient, sap, sizeof(cb_addr));
386 if (error < 0)
387 goto error;
388 error = rpc_ntop(sap, buf, sizeof(buf));
389 if (error < 0)
390 goto error;
391 ip_addr = (const char *)buf;
393 strlcpy(clp->cl_ipaddr, ip_addr, sizeof(clp->cl_ipaddr));
395 error = nfs_idmap_new(clp);
396 if (error < 0) {
397 dprintk("%s: failed to create idmapper. Error = %d\n",
398 __func__, error);
399 goto error;
401 __set_bit(NFS_CS_IDMAP, &clp->cl_res_state);
403 error = nfs4_init_client_minor_version(clp);
404 if (error < 0)
405 goto error;
407 error = nfs4_discover_server_trunking(clp, &old);
408 if (error < 0)
409 goto error;
411 if (clp != old) {
412 clp->cl_preserve_clid = true;
414 * Mark the client as having failed initialization so other
415 * processes walking the nfs_client_list in nfs_match_client()
416 * won't try to use it.
418 nfs_mark_client_ready(clp, -EPERM);
420 nfs_put_client(clp);
421 clear_bit(NFS_CS_TSM_POSSIBLE, &clp->cl_flags);
422 return old;
424 error:
425 nfs_mark_client_ready(clp, error);
426 nfs_put_client(clp);
427 return ERR_PTR(error);
431 * SETCLIENTID just did a callback update with the callback ident in
432 * "drop," but server trunking discovery claims "drop" and "keep" are
433 * actually the same server. Swap the callback IDs so that "keep"
434 * will continue to use the callback ident the server now knows about,
435 * and so that "keep"'s original callback ident is destroyed when
436 * "drop" is freed.
438 static void nfs4_swap_callback_idents(struct nfs_client *keep,
439 struct nfs_client *drop)
441 struct nfs_net *nn = net_generic(keep->cl_net, nfs_net_id);
442 unsigned int save = keep->cl_cb_ident;
444 if (keep->cl_cb_ident == drop->cl_cb_ident)
445 return;
447 dprintk("%s: keeping callback ident %u and dropping ident %u\n",
448 __func__, keep->cl_cb_ident, drop->cl_cb_ident);
450 spin_lock(&nn->nfs_client_lock);
452 idr_replace(&nn->cb_ident_idr, keep, drop->cl_cb_ident);
453 keep->cl_cb_ident = drop->cl_cb_ident;
455 idr_replace(&nn->cb_ident_idr, drop, save);
456 drop->cl_cb_ident = save;
458 spin_unlock(&nn->nfs_client_lock);
461 static bool nfs4_match_client_owner_id(const struct nfs_client *clp1,
462 const struct nfs_client *clp2)
464 if (clp1->cl_owner_id == NULL || clp2->cl_owner_id == NULL)
465 return true;
466 return strcmp(clp1->cl_owner_id, clp2->cl_owner_id) == 0;
469 static bool nfs4_same_verifier(nfs4_verifier *v1, nfs4_verifier *v2)
471 return memcmp(v1->data, v2->data, sizeof(v1->data)) == 0;
474 static int nfs4_match_client(struct nfs_client *pos, struct nfs_client *new,
475 struct nfs_client **prev, struct nfs_net *nn)
477 int status;
479 if (pos->rpc_ops != new->rpc_ops)
480 return 1;
482 if (pos->cl_minorversion != new->cl_minorversion)
483 return 1;
485 /* If "pos" isn't marked ready, we can't trust the
486 * remaining fields in "pos", especially the client
487 * ID and serverowner fields. Wait for CREATE_SESSION
488 * to finish. */
489 if (pos->cl_cons_state > NFS_CS_READY) {
490 atomic_inc(&pos->cl_count);
491 spin_unlock(&nn->nfs_client_lock);
493 nfs_put_client(*prev);
494 *prev = pos;
496 status = nfs_wait_client_init_complete(pos);
497 spin_lock(&nn->nfs_client_lock);
499 if (status < 0)
500 return status;
503 if (pos->cl_cons_state != NFS_CS_READY)
504 return 1;
506 if (pos->cl_clientid != new->cl_clientid)
507 return 1;
509 /* NFSv4.1 always uses the uniform string, however someone
510 * might switch the uniquifier string on us.
512 if (!nfs4_match_client_owner_id(pos, new))
513 return 1;
515 return 0;
519 * nfs40_walk_client_list - Find server that recognizes a client ID
521 * @new: nfs_client with client ID to test
522 * @result: OUT: found nfs_client, or new
523 * @cred: credential to use for trunking test
525 * Returns zero, a negative errno, or a negative NFS4ERR status.
526 * If zero is returned, an nfs_client pointer is planted in "result."
528 * NB: nfs40_walk_client_list() relies on the new nfs_client being
529 * the last nfs_client on the list.
531 int nfs40_walk_client_list(struct nfs_client *new,
532 struct nfs_client **result,
533 struct rpc_cred *cred)
535 struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
536 struct nfs_client *pos, *prev = NULL;
537 struct nfs4_setclientid_res clid = {
538 .clientid = new->cl_clientid,
539 .confirm = new->cl_confirm,
541 int status = -NFS4ERR_STALE_CLIENTID;
543 spin_lock(&nn->nfs_client_lock);
544 list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
546 if (pos == new)
547 goto found;
549 status = nfs4_match_client(pos, new, &prev, nn);
550 if (status < 0)
551 goto out_unlock;
552 if (status != 0)
553 continue;
555 * We just sent a new SETCLIENTID, which should have
556 * caused the server to return a new cl_confirm. So if
557 * cl_confirm is the same, then this is a different
558 * server that just returned the same cl_confirm by
559 * coincidence:
561 if ((new != pos) && nfs4_same_verifier(&pos->cl_confirm,
562 &new->cl_confirm))
563 continue;
565 * But if the cl_confirm's are different, then the only
566 * way that a SETCLIENTID_CONFIRM to pos can succeed is
567 * if new and pos point to the same server:
569 found:
570 atomic_inc(&pos->cl_count);
571 spin_unlock(&nn->nfs_client_lock);
573 nfs_put_client(prev);
574 prev = pos;
576 status = nfs4_proc_setclientid_confirm(pos, &clid, cred);
577 switch (status) {
578 case -NFS4ERR_STALE_CLIENTID:
579 break;
580 case 0:
581 nfs4_swap_callback_idents(pos, new);
582 pos->cl_confirm = new->cl_confirm;
583 nfs_mark_client_ready(pos, NFS_CS_READY);
585 prev = NULL;
586 *result = pos;
587 goto out;
588 case -ERESTARTSYS:
589 case -ETIMEDOUT:
590 /* The callback path may have been inadvertently
591 * changed. Schedule recovery!
593 nfs4_schedule_path_down_recovery(pos);
594 default:
595 goto out;
598 spin_lock(&nn->nfs_client_lock);
600 out_unlock:
601 spin_unlock(&nn->nfs_client_lock);
603 /* No match found. The server lost our clientid */
604 out:
605 nfs_put_client(prev);
606 return status;
609 #ifdef CONFIG_NFS_V4_1
611 * Returns true if the server major ids match
613 static bool
614 nfs4_check_serverowner_major_id(struct nfs41_server_owner *o1,
615 struct nfs41_server_owner *o2)
617 if (o1->major_id_sz != o2->major_id_sz)
618 return false;
619 return memcmp(o1->major_id, o2->major_id, o1->major_id_sz) == 0;
623 * Returns true if the server scopes match
625 static bool
626 nfs4_check_server_scope(struct nfs41_server_scope *s1,
627 struct nfs41_server_scope *s2)
629 if (s1->server_scope_sz != s2->server_scope_sz)
630 return false;
631 return memcmp(s1->server_scope, s2->server_scope,
632 s1->server_scope_sz) == 0;
636 * nfs4_detect_session_trunking - Checks for session trunking.
638 * Called after a successful EXCHANGE_ID on a multi-addr connection.
639 * Upon success, add the transport.
641 * @clp: original mount nfs_client
642 * @res: result structure from an exchange_id using the original mount
643 * nfs_client with a new multi_addr transport
645 * Returns zero on success, otherwise -EINVAL
647 * Note: since the exchange_id for the new multi_addr transport uses the
648 * same nfs_client from the original mount, the cl_owner_id is reused,
649 * so eir_clientowner is the same.
651 int nfs4_detect_session_trunking(struct nfs_client *clp,
652 struct nfs41_exchange_id_res *res,
653 struct rpc_xprt *xprt)
655 /* Check eir_clientid */
656 if (clp->cl_clientid != res->clientid)
657 goto out_err;
659 /* Check eir_server_owner so_major_id */
660 if (!nfs4_check_serverowner_major_id(clp->cl_serverowner,
661 res->server_owner))
662 goto out_err;
664 /* Check eir_server_owner so_minor_id */
665 if (clp->cl_serverowner->minor_id != res->server_owner->minor_id)
666 goto out_err;
668 /* Check eir_server_scope */
669 if (!nfs4_check_server_scope(clp->cl_serverscope, res->server_scope))
670 goto out_err;
672 pr_info("NFS: %s: Session trunking succeeded for %s\n",
673 clp->cl_hostname,
674 xprt->address_strings[RPC_DISPLAY_ADDR]);
676 return 0;
677 out_err:
678 pr_info("NFS: %s: Session trunking failed for %s\n", clp->cl_hostname,
679 xprt->address_strings[RPC_DISPLAY_ADDR]);
681 return -EINVAL;
685 * nfs41_walk_client_list - Find nfs_client that matches a client/server owner
687 * @new: nfs_client with client ID to test
688 * @result: OUT: found nfs_client, or new
689 * @cred: credential to use for trunking test
691 * Returns zero, a negative errno, or a negative NFS4ERR status.
692 * If zero is returned, an nfs_client pointer is planted in "result."
694 * NB: nfs41_walk_client_list() relies on the new nfs_client being
695 * the last nfs_client on the list.
697 int nfs41_walk_client_list(struct nfs_client *new,
698 struct nfs_client **result,
699 struct rpc_cred *cred)
701 struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
702 struct nfs_client *pos, *prev = NULL;
703 int status = -NFS4ERR_STALE_CLIENTID;
705 spin_lock(&nn->nfs_client_lock);
706 list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
708 if (pos == new)
709 goto found;
711 status = nfs4_match_client(pos, new, &prev, nn);
712 if (status < 0)
713 goto out;
714 if (status != 0)
715 continue;
718 * Note that session trunking is just a special subcase of
719 * client id trunking. In either case, we want to fall back
720 * to using the existing nfs_client.
722 if (!nfs4_check_serverowner_major_id(pos->cl_serverowner,
723 new->cl_serverowner))
724 continue;
726 found:
727 atomic_inc(&pos->cl_count);
728 *result = pos;
729 status = 0;
730 break;
733 out:
734 spin_unlock(&nn->nfs_client_lock);
735 nfs_put_client(prev);
736 return status;
738 #endif /* CONFIG_NFS_V4_1 */
740 static void nfs4_destroy_server(struct nfs_server *server)
742 LIST_HEAD(freeme);
744 nfs_server_return_all_delegations(server);
745 unset_pnfs_layoutdriver(server);
746 nfs4_purge_state_owners(server, &freeme);
747 nfs4_free_state_owners(&freeme);
751 * NFSv4.0 callback thread helper
753 * Find a client by callback identifier
755 struct nfs_client *
756 nfs4_find_client_ident(struct net *net, int cb_ident)
758 struct nfs_client *clp;
759 struct nfs_net *nn = net_generic(net, nfs_net_id);
761 spin_lock(&nn->nfs_client_lock);
762 clp = idr_find(&nn->cb_ident_idr, cb_ident);
763 if (clp)
764 atomic_inc(&clp->cl_count);
765 spin_unlock(&nn->nfs_client_lock);
766 return clp;
769 #if defined(CONFIG_NFS_V4_1)
770 /* Common match routine for v4.0 and v4.1 callback services */
771 static bool nfs4_cb_match_client(const struct sockaddr *addr,
772 struct nfs_client *clp, u32 minorversion)
774 struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
776 /* Don't match clients that failed to initialise */
777 if (!(clp->cl_cons_state == NFS_CS_READY ||
778 clp->cl_cons_state == NFS_CS_SESSION_INITING))
779 return false;
781 smp_rmb();
783 /* Match the version and minorversion */
784 if (clp->rpc_ops->version != 4 ||
785 clp->cl_minorversion != minorversion)
786 return false;
788 /* Match only the IP address, not the port number */
789 return rpc_cmp_addr(addr, clap);
793 * NFSv4.1 callback thread helper
794 * For CB_COMPOUND calls, find a client by IP address, protocol version,
795 * minorversion, and sessionID
797 * Returns NULL if no such client
799 struct nfs_client *
800 nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
801 struct nfs4_sessionid *sid, u32 minorversion)
803 struct nfs_client *clp;
804 struct nfs_net *nn = net_generic(net, nfs_net_id);
806 spin_lock(&nn->nfs_client_lock);
807 list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
808 if (nfs4_cb_match_client(addr, clp, minorversion) == false)
809 continue;
811 if (!nfs4_has_session(clp))
812 continue;
814 /* Match sessionid*/
815 if (memcmp(clp->cl_session->sess_id.data,
816 sid->data, NFS4_MAX_SESSIONID_LEN) != 0)
817 continue;
819 atomic_inc(&clp->cl_count);
820 spin_unlock(&nn->nfs_client_lock);
821 return clp;
823 spin_unlock(&nn->nfs_client_lock);
824 return NULL;
827 #else /* CONFIG_NFS_V4_1 */
829 struct nfs_client *
830 nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
831 struct nfs4_sessionid *sid, u32 minorversion)
833 return NULL;
835 #endif /* CONFIG_NFS_V4_1 */
838 * Set up an NFS4 client
840 static int nfs4_set_client(struct nfs_server *server,
841 const char *hostname,
842 const struct sockaddr *addr,
843 const size_t addrlen,
844 const char *ip_addr,
845 int proto, const struct rpc_timeout *timeparms,
846 u32 minorversion, struct net *net)
848 struct nfs_client_initdata cl_init = {
849 .hostname = hostname,
850 .addr = addr,
851 .addrlen = addrlen,
852 .ip_addr = ip_addr,
853 .nfs_mod = &nfs_v4,
854 .proto = proto,
855 .minorversion = minorversion,
856 .net = net,
857 .timeparms = timeparms,
859 struct nfs_client *clp;
861 if (server->flags & NFS_MOUNT_NORESVPORT)
862 set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
863 if (server->options & NFS_OPTION_MIGRATION)
864 set_bit(NFS_CS_MIGRATION, &cl_init.init_flags);
865 if (test_bit(NFS_MIG_TSM_POSSIBLE, &server->mig_status))
866 set_bit(NFS_CS_TSM_POSSIBLE, &cl_init.init_flags);
868 /* Allocate or find a client reference we can use */
869 clp = nfs_get_client(&cl_init);
870 if (IS_ERR(clp))
871 return PTR_ERR(clp);
873 if (server->nfs_client == clp) {
874 nfs_put_client(clp);
875 return -ELOOP;
879 * Query for the lease time on clientid setup or renewal
881 * Note that this will be set on nfs_clients that were created
882 * only for the DS role and did not set this bit, but now will
883 * serve a dual role.
885 set_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state);
887 server->nfs_client = clp;
888 return 0;
892 * Set up a pNFS Data Server client.
894 * Return any existing nfs_client that matches server address,port,version
895 * and minorversion.
897 * For a new nfs_client, use a soft mount (default), a low retrans and a
898 * low timeout interval so that if a connection is lost, we retry through
899 * the MDS.
901 struct nfs_client *nfs4_set_ds_client(struct nfs_server *mds_srv,
902 const struct sockaddr *ds_addr, int ds_addrlen,
903 int ds_proto, unsigned int ds_timeo, unsigned int ds_retrans,
904 u32 minor_version)
906 struct rpc_timeout ds_timeout;
907 struct nfs_client *mds_clp = mds_srv->nfs_client;
908 struct nfs_client_initdata cl_init = {
909 .addr = ds_addr,
910 .addrlen = ds_addrlen,
911 .nodename = mds_clp->cl_rpcclient->cl_nodename,
912 .ip_addr = mds_clp->cl_ipaddr,
913 .nfs_mod = &nfs_v4,
914 .proto = ds_proto,
915 .minorversion = minor_version,
916 .net = mds_clp->cl_net,
917 .timeparms = &ds_timeout,
919 char buf[INET6_ADDRSTRLEN + 1];
921 if (rpc_ntop(ds_addr, buf, sizeof(buf)) <= 0)
922 return ERR_PTR(-EINVAL);
923 cl_init.hostname = buf;
925 if (mds_srv->flags & NFS_MOUNT_NORESVPORT)
926 __set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
929 * Set an authflavor equual to the MDS value. Use the MDS nfs_client
930 * cl_ipaddr so as to use the same EXCHANGE_ID co_ownerid as the MDS
931 * (section 13.1 RFC 5661).
933 nfs_init_timeout_values(&ds_timeout, ds_proto, ds_timeo, ds_retrans);
934 return nfs_get_client(&cl_init);
936 EXPORT_SYMBOL_GPL(nfs4_set_ds_client);
939 * Session has been established, and the client marked ready.
940 * Limit the mount rsize, wsize and dtsize using negotiated fore
941 * channel attributes.
943 static void nfs4_session_limit_rwsize(struct nfs_server *server)
945 #ifdef CONFIG_NFS_V4_1
946 struct nfs4_session *sess;
947 u32 server_resp_sz;
948 u32 server_rqst_sz;
950 if (!nfs4_has_session(server->nfs_client))
951 return;
952 sess = server->nfs_client->cl_session;
953 server_resp_sz = sess->fc_attrs.max_resp_sz - nfs41_maxread_overhead;
954 server_rqst_sz = sess->fc_attrs.max_rqst_sz - nfs41_maxwrite_overhead;
956 if (server->dtsize > server_resp_sz)
957 server->dtsize = server_resp_sz;
958 if (server->rsize > server_resp_sz)
959 server->rsize = server_resp_sz;
960 if (server->wsize > server_rqst_sz)
961 server->wsize = server_rqst_sz;
962 #endif /* CONFIG_NFS_V4_1 */
965 static int nfs4_server_common_setup(struct nfs_server *server,
966 struct nfs_fh *mntfh, bool auth_probe)
968 struct nfs_fattr *fattr;
969 int error;
971 /* data servers support only a subset of NFSv4.1 */
972 if (is_ds_only_client(server->nfs_client))
973 return -EPROTONOSUPPORT;
975 fattr = nfs_alloc_fattr();
976 if (fattr == NULL)
977 return -ENOMEM;
979 /* We must ensure the session is initialised first */
980 error = nfs4_init_session(server->nfs_client);
981 if (error < 0)
982 goto out;
984 /* Set the basic capabilities */
985 server->caps |= server->nfs_client->cl_mvops->init_caps;
986 if (server->flags & NFS_MOUNT_NORDIRPLUS)
987 server->caps &= ~NFS_CAP_READDIRPLUS;
989 * Don't use NFS uid/gid mapping if we're using AUTH_SYS or lower
990 * authentication.
992 if (nfs4_disable_idmapping &&
993 server->client->cl_auth->au_flavor == RPC_AUTH_UNIX)
994 server->caps |= NFS_CAP_UIDGID_NOMAP;
997 /* Probe the root fh to retrieve its FSID and filehandle */
998 error = nfs4_get_rootfh(server, mntfh, auth_probe);
999 if (error < 0)
1000 goto out;
1002 dprintk("Server FSID: %llx:%llx\n",
1003 (unsigned long long) server->fsid.major,
1004 (unsigned long long) server->fsid.minor);
1005 nfs_display_fhandle(mntfh, "Pseudo-fs root FH");
1007 error = nfs_probe_fsinfo(server, mntfh, fattr);
1008 if (error < 0)
1009 goto out;
1011 nfs4_session_limit_rwsize(server);
1013 if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1014 server->namelen = NFS4_MAXNAMLEN;
1016 nfs_server_insert_lists(server);
1017 server->mount_time = jiffies;
1018 server->destroy = nfs4_destroy_server;
1019 out:
1020 nfs_free_fattr(fattr);
1021 return error;
1025 * Create a version 4 volume record
1027 static int nfs4_init_server(struct nfs_server *server,
1028 struct nfs_parsed_mount_data *data)
1030 struct rpc_timeout timeparms;
1031 int error;
1033 nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
1034 data->timeo, data->retrans);
1036 /* Initialise the client representation from the mount data */
1037 server->flags = data->flags;
1038 server->options = data->options;
1039 server->auth_info = data->auth_info;
1041 /* Use the first specified auth flavor. If this flavor isn't
1042 * allowed by the server, use the SECINFO path to try the
1043 * other specified flavors */
1044 if (data->auth_info.flavor_len >= 1)
1045 data->selected_flavor = data->auth_info.flavors[0];
1046 else
1047 data->selected_flavor = RPC_AUTH_UNIX;
1049 /* Get a client record */
1050 error = nfs4_set_client(server,
1051 data->nfs_server.hostname,
1052 (const struct sockaddr *)&data->nfs_server.address,
1053 data->nfs_server.addrlen,
1054 data->client_address,
1055 data->nfs_server.protocol,
1056 &timeparms,
1057 data->minorversion,
1058 data->net);
1059 if (error < 0)
1060 return error;
1062 if (data->rsize)
1063 server->rsize = nfs_block_size(data->rsize, NULL);
1064 if (data->wsize)
1065 server->wsize = nfs_block_size(data->wsize, NULL);
1067 server->acregmin = data->acregmin * HZ;
1068 server->acregmax = data->acregmax * HZ;
1069 server->acdirmin = data->acdirmin * HZ;
1070 server->acdirmax = data->acdirmax * HZ;
1071 server->port = data->nfs_server.port;
1073 return nfs_init_server_rpcclient(server, &timeparms,
1074 data->selected_flavor);
1078 * Create a version 4 volume record
1079 * - keyed on server and FSID
1081 /*struct nfs_server *nfs4_create_server(const struct nfs_parsed_mount_data *data,
1082 struct nfs_fh *mntfh)*/
1083 struct nfs_server *nfs4_create_server(struct nfs_mount_info *mount_info,
1084 struct nfs_subversion *nfs_mod)
1086 struct nfs_server *server;
1087 bool auth_probe;
1088 int error;
1090 server = nfs_alloc_server();
1091 if (!server)
1092 return ERR_PTR(-ENOMEM);
1094 auth_probe = mount_info->parsed->auth_info.flavor_len < 1;
1096 /* set up the general RPC client */
1097 error = nfs4_init_server(server, mount_info->parsed);
1098 if (error < 0)
1099 goto error;
1101 error = nfs4_server_common_setup(server, mount_info->mntfh, auth_probe);
1102 if (error < 0)
1103 goto error;
1105 return server;
1107 error:
1108 nfs_free_server(server);
1109 return ERR_PTR(error);
1113 * Create an NFS4 referral server record
1115 struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *data,
1116 struct nfs_fh *mntfh)
1118 struct nfs_client *parent_client;
1119 struct nfs_server *server, *parent_server;
1120 bool auth_probe;
1121 int error;
1123 server = nfs_alloc_server();
1124 if (!server)
1125 return ERR_PTR(-ENOMEM);
1127 parent_server = NFS_SB(data->sb);
1128 parent_client = parent_server->nfs_client;
1130 /* Initialise the client representation from the parent server */
1131 nfs_server_copy_userdata(server, parent_server);
1133 /* Get a client representation.
1134 * Note: NFSv4 always uses TCP, */
1135 error = nfs4_set_client(server, data->hostname,
1136 data->addr,
1137 data->addrlen,
1138 parent_client->cl_ipaddr,
1139 rpc_protocol(parent_server->client),
1140 parent_server->client->cl_timeout,
1141 parent_client->cl_mvops->minor_version,
1142 parent_client->cl_net);
1143 if (error < 0)
1144 goto error;
1146 error = nfs_init_server_rpcclient(server, parent_server->client->cl_timeout, data->authflavor);
1147 if (error < 0)
1148 goto error;
1150 auth_probe = parent_server->auth_info.flavor_len < 1;
1152 error = nfs4_server_common_setup(server, mntfh, auth_probe);
1153 if (error < 0)
1154 goto error;
1156 return server;
1158 error:
1159 nfs_free_server(server);
1160 return ERR_PTR(error);
1164 * Grab the destination's particulars, including lease expiry time.
1166 * Returns zero if probe succeeded and retrieved FSID matches the FSID
1167 * we have cached.
1169 static int nfs_probe_destination(struct nfs_server *server)
1171 struct inode *inode = d_inode(server->super->s_root);
1172 struct nfs_fattr *fattr;
1173 int error;
1175 fattr = nfs_alloc_fattr();
1176 if (fattr == NULL)
1177 return -ENOMEM;
1179 /* Sanity: the probe won't work if the destination server
1180 * does not recognize the migrated FH. */
1181 error = nfs_probe_fsinfo(server, NFS_FH(inode), fattr);
1183 nfs_free_fattr(fattr);
1184 return error;
1188 * nfs4_update_server - Move an nfs_server to a different nfs_client
1190 * @server: represents FSID to be moved
1191 * @hostname: new end-point's hostname
1192 * @sap: new end-point's socket address
1193 * @salen: size of "sap"
1194 * @net: net namespace
1196 * The nfs_server must be quiescent before this function is invoked.
1197 * Either its session is drained (NFSv4.1+), or its transport is
1198 * plugged and drained (NFSv4.0).
1200 * Returns zero on success, or a negative errno value.
1202 int nfs4_update_server(struct nfs_server *server, const char *hostname,
1203 struct sockaddr *sap, size_t salen, struct net *net)
1205 struct nfs_client *clp = server->nfs_client;
1206 struct rpc_clnt *clnt = server->client;
1207 struct xprt_create xargs = {
1208 .ident = clp->cl_proto,
1209 .net = net,
1210 .dstaddr = sap,
1211 .addrlen = salen,
1212 .servername = hostname,
1214 char buf[INET6_ADDRSTRLEN + 1];
1215 struct sockaddr_storage address;
1216 struct sockaddr *localaddr = (struct sockaddr *)&address;
1217 int error;
1219 error = rpc_switch_client_transport(clnt, &xargs, clnt->cl_timeout);
1220 if (error != 0)
1221 return error;
1223 error = rpc_localaddr(clnt, localaddr, sizeof(address));
1224 if (error != 0)
1225 return error;
1227 if (rpc_ntop(localaddr, buf, sizeof(buf)) == 0)
1228 return -EAFNOSUPPORT;
1230 nfs_server_remove_lists(server);
1231 set_bit(NFS_MIG_TSM_POSSIBLE, &server->mig_status);
1232 error = nfs4_set_client(server, hostname, sap, salen, buf,
1233 clp->cl_proto, clnt->cl_timeout,
1234 clp->cl_minorversion, net);
1235 clear_bit(NFS_MIG_TSM_POSSIBLE, &server->mig_status);
1236 if (error != 0) {
1237 nfs_server_insert_lists(server);
1238 return error;
1240 nfs_put_client(clp);
1242 if (server->nfs_client->cl_hostname == NULL)
1243 server->nfs_client->cl_hostname = kstrdup(hostname, GFP_KERNEL);
1244 nfs_server_insert_lists(server);
1246 return nfs_probe_destination(server);