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1/*
2 * linux/fs/nfs/callback_proc.c
3 *
4 * Copyright (C) 2004 Trond Myklebust
5 *
6 * NFSv4 callback procedures
7 */
8#include <linux/nfs4.h>
9#include <linux/nfs_fs.h>
10#include <linux/slab.h>
11#include <linux/rcupdate.h>
12#include "nfs4_fs.h"
13#include "callback.h"
14#include "delegation.h"
15#include "internal.h"
16#include "pnfs.h"
17
18#ifdef NFS_DEBUG
19#define NFSDBG_FACILITY NFSDBG_CALLBACK
20#endif
21
22__be32 nfs4_callback_getattr(struct cb_getattrargs *args,
23 struct cb_getattrres *res,
24 struct cb_process_state *cps)
25{
26 struct nfs_delegation *delegation;
27 struct nfs_inode *nfsi;
28 struct inode *inode;
29
30 res->status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
31 if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */
32 goto out;
33
34 res->bitmap[0] = res->bitmap[1] = 0;
35 res->status = htonl(NFS4ERR_BADHANDLE);
36
37 dprintk_rcu("NFS: GETATTR callback request from %s\n",
38 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
39
40 inode = nfs_delegation_find_inode(cps->clp, &args->fh);
41 if (inode == NULL)
42 goto out;
43 nfsi = NFS_I(inode);
44 rcu_read_lock();
45 delegation = rcu_dereference(nfsi->delegation);
46 if (delegation == NULL || (delegation->type & FMODE_WRITE) == 0)
47 goto out_iput;
48 res->size = i_size_read(inode);
49 res->change_attr = delegation->change_attr;
50 if (nfsi->npages != 0)
51 res->change_attr++;
52 res->ctime = inode->i_ctime;
53 res->mtime = inode->i_mtime;
54 res->bitmap[0] = (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE) &
55 args->bitmap[0];
56 res->bitmap[1] = (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY) &
57 args->bitmap[1];
58 res->status = 0;
59out_iput:
60 rcu_read_unlock();
61 iput(inode);
62out:
63 dprintk("%s: exit with status = %d\n", __func__, ntohl(res->status));
64 return res->status;
65}
66
67__be32 nfs4_callback_recall(struct cb_recallargs *args, void *dummy,
68 struct cb_process_state *cps)
69{
70 struct inode *inode;
71 __be32 res;
72
73 res = htonl(NFS4ERR_OP_NOT_IN_SESSION);
74 if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */
75 goto out;
76
77 dprintk_rcu("NFS: RECALL callback request from %s\n",
78 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
79
80 res = htonl(NFS4ERR_BADHANDLE);
81 inode = nfs_delegation_find_inode(cps->clp, &args->fh);
82 if (inode == NULL)
83 goto out;
84 /* Set up a helper thread to actually return the delegation */
85 switch (nfs_async_inode_return_delegation(inode, &args->stateid)) {
86 case 0:
87 res = 0;
88 break;
89 case -ENOENT:
90 res = htonl(NFS4ERR_BAD_STATEID);
91 break;
92 default:
93 res = htonl(NFS4ERR_RESOURCE);
94 }
95 iput(inode);
96out:
97 dprintk("%s: exit with status = %d\n", __func__, ntohl(res));
98 return res;
99}
100
101#if defined(CONFIG_NFS_V4_1)
102
103/*
104 * Lookup a layout by filehandle.
105 *
106 * Note: gets a refcount on the layout hdr and on its respective inode.
107 * Caller must put the layout hdr and the inode.
108 *
109 * TODO: keep track of all layouts (and delegations) in a hash table
110 * hashed by filehandle.
111 */
112static struct pnfs_layout_hdr * get_layout_by_fh_locked(struct nfs_client *clp, struct nfs_fh *fh)
113{
114 struct nfs_server *server;
115 struct inode *ino;
116 struct pnfs_layout_hdr *lo;
117
118 list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
119 list_for_each_entry(lo, &server->layouts, plh_layouts) {
120 if (nfs_compare_fh(fh, &NFS_I(lo->plh_inode)->fh))
121 continue;
122 ino = igrab(lo->plh_inode);
123 if (!ino)
124 continue;
125 get_layout_hdr(lo);
126 return lo;
127 }
128 }
129
130 return NULL;
131}
132
133static struct pnfs_layout_hdr * get_layout_by_fh(struct nfs_client *clp, struct nfs_fh *fh)
134{
135 struct pnfs_layout_hdr *lo;
136
137 spin_lock(&clp->cl_lock);
138 rcu_read_lock();
139 lo = get_layout_by_fh_locked(clp, fh);
140 rcu_read_unlock();
141 spin_unlock(&clp->cl_lock);
142
143 return lo;
144}
145
146static u32 initiate_file_draining(struct nfs_client *clp,
147 struct cb_layoutrecallargs *args)
148{
149 struct inode *ino;
150 struct pnfs_layout_hdr *lo;
151 u32 rv = NFS4ERR_NOMATCHING_LAYOUT;
152 LIST_HEAD(free_me_list);
153
154 lo = get_layout_by_fh(clp, &args->cbl_fh);
155 if (!lo)
156 return NFS4ERR_NOMATCHING_LAYOUT;
157
158 ino = lo->plh_inode;
159 spin_lock(&ino->i_lock);
160 if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags) ||
161 mark_matching_lsegs_invalid(lo, &free_me_list,
162 &args->cbl_range))
163 rv = NFS4ERR_DELAY;
164 else
165 rv = NFS4ERR_NOMATCHING_LAYOUT;
166 pnfs_set_layout_stateid(lo, &args->cbl_stateid, true);
167 spin_unlock(&ino->i_lock);
168 pnfs_free_lseg_list(&free_me_list);
169 put_layout_hdr(lo);
170 iput(ino);
171 return rv;
172}
173
174static u32 initiate_bulk_draining(struct nfs_client *clp,
175 struct cb_layoutrecallargs *args)
176{
177 struct nfs_server *server;
178 struct pnfs_layout_hdr *lo;
179 struct inode *ino;
180 u32 rv = NFS4ERR_NOMATCHING_LAYOUT;
181 struct pnfs_layout_hdr *tmp;
182 LIST_HEAD(recall_list);
183 LIST_HEAD(free_me_list);
184 struct pnfs_layout_range range = {
185 .iomode = IOMODE_ANY,
186 .offset = 0,
187 .length = NFS4_MAX_UINT64,
188 };
189
190 spin_lock(&clp->cl_lock);
191 rcu_read_lock();
192 list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
193 if ((args->cbl_recall_type == RETURN_FSID) &&
194 memcmp(&server->fsid, &args->cbl_fsid,
195 sizeof(struct nfs_fsid)))
196 continue;
197
198 list_for_each_entry(lo, &server->layouts, plh_layouts) {
199 if (!igrab(lo->plh_inode))
200 continue;
201 get_layout_hdr(lo);
202 BUG_ON(!list_empty(&lo->plh_bulk_recall));
203 list_add(&lo->plh_bulk_recall, &recall_list);
204 }
205 }
206 rcu_read_unlock();
207 spin_unlock(&clp->cl_lock);
208
209 list_for_each_entry_safe(lo, tmp,
210 &recall_list, plh_bulk_recall) {
211 ino = lo->plh_inode;
212 spin_lock(&ino->i_lock);
213 set_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
214 if (mark_matching_lsegs_invalid(lo, &free_me_list, &range))
215 rv = NFS4ERR_DELAY;
216 list_del_init(&lo->plh_bulk_recall);
217 spin_unlock(&ino->i_lock);
218 pnfs_free_lseg_list(&free_me_list);
219 put_layout_hdr(lo);
220 iput(ino);
221 }
222 return rv;
223}
224
225static u32 do_callback_layoutrecall(struct nfs_client *clp,
226 struct cb_layoutrecallargs *args)
227{
228 u32 res;
229
230 dprintk("%s enter, type=%i\n", __func__, args->cbl_recall_type);
231 if (args->cbl_recall_type == RETURN_FILE)
232 res = initiate_file_draining(clp, args);
233 else
234 res = initiate_bulk_draining(clp, args);
235 dprintk("%s returning %i\n", __func__, res);
236 return res;
237
238}
239
240__be32 nfs4_callback_layoutrecall(struct cb_layoutrecallargs *args,
241 void *dummy, struct cb_process_state *cps)
242{
243 u32 res;
244
245 dprintk("%s: -->\n", __func__);
246
247 if (cps->clp)
248 res = do_callback_layoutrecall(cps->clp, args);
249 else
250 res = NFS4ERR_OP_NOT_IN_SESSION;
251
252 dprintk("%s: exit with status = %d\n", __func__, res);
253 return cpu_to_be32(res);
254}
255
256static void pnfs_recall_all_layouts(struct nfs_client *clp)
257{
258 struct cb_layoutrecallargs args;
259
260 /* Pretend we got a CB_LAYOUTRECALL(ALL) */
261 memset(&args, 0, sizeof(args));
262 args.cbl_recall_type = RETURN_ALL;
263 /* FIXME we ignore errors, what should we do? */
264 do_callback_layoutrecall(clp, &args);
265}
266
267__be32 nfs4_callback_devicenotify(struct cb_devicenotifyargs *args,
268 void *dummy, struct cb_process_state *cps)
269{
270 int i;
271 __be32 res = 0;
272 struct nfs_client *clp = cps->clp;
273 struct nfs_server *server = NULL;
274
275 dprintk("%s: -->\n", __func__);
276
277 if (!clp) {
278 res = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION);
279 goto out;
280 }
281
282 for (i = 0; i < args->ndevs; i++) {
283 struct cb_devicenotifyitem *dev = &args->devs[i];
284
285 if (!server ||
286 server->pnfs_curr_ld->id != dev->cbd_layout_type) {
287 rcu_read_lock();
288 list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
289 if (server->pnfs_curr_ld &&
290 server->pnfs_curr_ld->id == dev->cbd_layout_type) {
291 rcu_read_unlock();
292 goto found;
293 }
294 rcu_read_unlock();
295 dprintk("%s: layout type %u not found\n",
296 __func__, dev->cbd_layout_type);
297 continue;
298 }
299
300 found:
301 if (dev->cbd_notify_type == NOTIFY_DEVICEID4_CHANGE)
302 dprintk("%s: NOTIFY_DEVICEID4_CHANGE not supported, "
303 "deleting instead\n", __func__);
304 nfs4_delete_deviceid(server->pnfs_curr_ld, clp, &dev->cbd_dev_id);
305 }
306
307out:
308 kfree(args->devs);
309 dprintk("%s: exit with status = %u\n",
310 __func__, be32_to_cpu(res));
311 return res;
312}
313
314/*
315 * Validate the sequenceID sent by the server.
316 * Return success if the sequenceID is one more than what we last saw on
317 * this slot, accounting for wraparound. Increments the slot's sequence.
318 *
319 * We don't yet implement a duplicate request cache, instead we set the
320 * back channel ca_maxresponsesize_cached to zero. This is OK for now
321 * since we only currently implement idempotent callbacks anyway.
322 *
323 * We have a single slot backchannel at this time, so we don't bother
324 * checking the used_slots bit array on the table. The lower layer guarantees
325 * a single outstanding callback request at a time.
326 */
327static __be32
328validate_seqid(struct nfs4_slot_table *tbl, struct cb_sequenceargs * args)
329{
330 struct nfs4_slot *slot;
331
332 dprintk("%s enter. slotid %d seqid %d\n",
333 __func__, args->csa_slotid, args->csa_sequenceid);
334
335 if (args->csa_slotid >= NFS41_BC_MAX_CALLBACKS)
336 return htonl(NFS4ERR_BADSLOT);
337
338 slot = tbl->slots + args->csa_slotid;
339 dprintk("%s slot table seqid: %d\n", __func__, slot->seq_nr);
340
341 /* Normal */
342 if (likely(args->csa_sequenceid == slot->seq_nr + 1)) {
343 slot->seq_nr++;
344 goto out_ok;
345 }
346
347 /* Replay */
348 if (args->csa_sequenceid == slot->seq_nr) {
349 dprintk("%s seqid %d is a replay\n",
350 __func__, args->csa_sequenceid);
351 /* Signal process_op to set this error on next op */
352 if (args->csa_cachethis == 0)
353 return htonl(NFS4ERR_RETRY_UNCACHED_REP);
354
355 /* The ca_maxresponsesize_cached is 0 with no DRC */
356 else if (args->csa_cachethis == 1)
357 return htonl(NFS4ERR_REP_TOO_BIG_TO_CACHE);
358 }
359
360 /* Wraparound */
361 if (args->csa_sequenceid == 1 && (slot->seq_nr + 1) == 0) {
362 slot->seq_nr = 1;
363 goto out_ok;
364 }
365
366 /* Misordered request */
367 return htonl(NFS4ERR_SEQ_MISORDERED);
368out_ok:
369 tbl->highest_used_slotid = args->csa_slotid;
370 return htonl(NFS4_OK);
371}
372
373/*
374 * For each referring call triple, check the session's slot table for
375 * a match. If the slot is in use and the sequence numbers match, the
376 * client is still waiting for a response to the original request.
377 */
378static bool referring_call_exists(struct nfs_client *clp,
379 uint32_t nrclists,
380 struct referring_call_list *rclists)
381{
382 bool status = 0;
383 int i, j;
384 struct nfs4_session *session;
385 struct nfs4_slot_table *tbl;
386 struct referring_call_list *rclist;
387 struct referring_call *ref;
388
389 /*
390 * XXX When client trunking is implemented, this becomes
391 * a session lookup from within the loop
392 */
393 session = clp->cl_session;
394 tbl = &session->fc_slot_table;
395
396 for (i = 0; i < nrclists; i++) {
397 rclist = &rclists[i];
398 if (memcmp(session->sess_id.data,
399 rclist->rcl_sessionid.data,
400 NFS4_MAX_SESSIONID_LEN) != 0)
401 continue;
402
403 for (j = 0; j < rclist->rcl_nrefcalls; j++) {
404 ref = &rclist->rcl_refcalls[j];
405
406 dprintk("%s: sessionid %x:%x:%x:%x sequenceid %u "
407 "slotid %u\n", __func__,
408 ((u32 *)&rclist->rcl_sessionid.data)[0],
409 ((u32 *)&rclist->rcl_sessionid.data)[1],
410 ((u32 *)&rclist->rcl_sessionid.data)[2],
411 ((u32 *)&rclist->rcl_sessionid.data)[3],
412 ref->rc_sequenceid, ref->rc_slotid);
413
414 spin_lock(&tbl->slot_tbl_lock);
415 status = (test_bit(ref->rc_slotid, tbl->used_slots) &&
416 tbl->slots[ref->rc_slotid].seq_nr ==
417 ref->rc_sequenceid);
418 spin_unlock(&tbl->slot_tbl_lock);
419 if (status)
420 goto out;
421 }
422 }
423
424out:
425 return status;
426}
427
428__be32 nfs4_callback_sequence(struct cb_sequenceargs *args,
429 struct cb_sequenceres *res,
430 struct cb_process_state *cps)
431{
432 struct nfs4_slot_table *tbl;
433 struct nfs_client *clp;
434 int i;
435 __be32 status = htonl(NFS4ERR_BADSESSION);
436
437 clp = nfs4_find_client_sessionid(cps->net, args->csa_addr, &args->csa_sessionid);
438 if (clp == NULL)
439 goto out;
440
441 tbl = &clp->cl_session->bc_slot_table;
442
443 spin_lock(&tbl->slot_tbl_lock);
444 /* state manager is resetting the session */
445 if (test_bit(NFS4_SESSION_DRAINING, &clp->cl_session->session_state)) {
446 spin_unlock(&tbl->slot_tbl_lock);
447 status = htonl(NFS4ERR_DELAY);
448 /* Return NFS4ERR_BADSESSION if we're draining the session
449 * in order to reset it.
450 */
451 if (test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
452 status = htonl(NFS4ERR_BADSESSION);
453 goto out;
454 }
455
456 status = validate_seqid(&clp->cl_session->bc_slot_table, args);
457 spin_unlock(&tbl->slot_tbl_lock);
458 if (status)
459 goto out;
460
461 cps->slotid = args->csa_slotid;
462
463 /*
464 * Check for pending referring calls. If a match is found, a
465 * related callback was received before the response to the original
466 * call.
467 */
468 if (referring_call_exists(clp, args->csa_nrclists, args->csa_rclists)) {
469 status = htonl(NFS4ERR_DELAY);
470 goto out;
471 }
472
473 memcpy(&res->csr_sessionid, &args->csa_sessionid,
474 sizeof(res->csr_sessionid));
475 res->csr_sequenceid = args->csa_sequenceid;
476 res->csr_slotid = args->csa_slotid;
477 res->csr_highestslotid = NFS41_BC_MAX_CALLBACKS - 1;
478 res->csr_target_highestslotid = NFS41_BC_MAX_CALLBACKS - 1;
479
480out:
481 cps->clp = clp; /* put in nfs4_callback_compound */
482 for (i = 0; i < args->csa_nrclists; i++)
483 kfree(args->csa_rclists[i].rcl_refcalls);
484 kfree(args->csa_rclists);
485
486 if (status == htonl(NFS4ERR_RETRY_UNCACHED_REP)) {
487 cps->drc_status = status;
488 status = 0;
489 } else
490 res->csr_status = status;
491
492 dprintk("%s: exit with status = %d res->csr_status %d\n", __func__,
493 ntohl(status), ntohl(res->csr_status));
494 return status;
495}
496
497static bool
498validate_bitmap_values(unsigned long mask)
499{
500 return (mask & ~RCA4_TYPE_MASK_ALL) == 0;
501}
502
503__be32 nfs4_callback_recallany(struct cb_recallanyargs *args, void *dummy,
504 struct cb_process_state *cps)
505{
506 __be32 status;
507 fmode_t flags = 0;
508
509 status = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION);
510 if (!cps->clp) /* set in cb_sequence */
511 goto out;
512
513 dprintk_rcu("NFS: RECALL_ANY callback request from %s\n",
514 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
515
516 status = cpu_to_be32(NFS4ERR_INVAL);
517 if (!validate_bitmap_values(args->craa_type_mask))
518 goto out;
519
520 status = cpu_to_be32(NFS4_OK);
521 if (test_bit(RCA4_TYPE_MASK_RDATA_DLG, (const unsigned long *)
522 &args->craa_type_mask))
523 flags = FMODE_READ;
524 if (test_bit(RCA4_TYPE_MASK_WDATA_DLG, (const unsigned long *)
525 &args->craa_type_mask))
526 flags |= FMODE_WRITE;
527 if (test_bit(RCA4_TYPE_MASK_FILE_LAYOUT, (const unsigned long *)
528 &args->craa_type_mask))
529 pnfs_recall_all_layouts(cps->clp);
530 if (flags)
531 nfs_expire_all_delegation_types(cps->clp, flags);
532out:
533 dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
534 return status;
535}
536
537/* Reduce the fore channel's max_slots to the target value */
538__be32 nfs4_callback_recallslot(struct cb_recallslotargs *args, void *dummy,
539 struct cb_process_state *cps)
540{
541 struct nfs4_slot_table *fc_tbl;
542 __be32 status;
543
544 status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
545 if (!cps->clp) /* set in cb_sequence */
546 goto out;
547
548 dprintk_rcu("NFS: CB_RECALL_SLOT request from %s target max slots %d\n",
549 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR),
550 args->crsa_target_max_slots);
551
552 fc_tbl = &cps->clp->cl_session->fc_slot_table;
553
554 status = htonl(NFS4ERR_BAD_HIGH_SLOT);
555 if (args->crsa_target_max_slots > fc_tbl->max_slots ||
556 args->crsa_target_max_slots < 1)
557 goto out;
558
559 status = htonl(NFS4_OK);
560 if (args->crsa_target_max_slots == fc_tbl->max_slots)
561 goto out;
562
563 fc_tbl->target_max_slots = args->crsa_target_max_slots;
564 nfs41_handle_recall_slot(cps->clp);
565out:
566 dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
567 return status;
568}
569#endif /* CONFIG_NFS_V4_1 */
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/fs/nfs/callback_proc.c
4 *
5 * Copyright (C) 2004 Trond Myklebust
6 *
7 * NFSv4 callback procedures
8 */
9
10#include <linux/errno.h>
11#include <linux/math.h>
12#include <linux/nfs4.h>
13#include <linux/nfs_fs.h>
14#include <linux/slab.h>
15#include <linux/rcupdate.h>
16#include <linux/types.h>
17
18#include "nfs4_fs.h"
19#include "callback.h"
20#include "delegation.h"
21#include "internal.h"
22#include "pnfs.h"
23#include "nfs4session.h"
24#include "nfs4trace.h"
25
26#define NFSDBG_FACILITY NFSDBG_CALLBACK
27
28__be32 nfs4_callback_getattr(void *argp, void *resp,
29 struct cb_process_state *cps)
30{
31 struct cb_getattrargs *args = argp;
32 struct cb_getattrres *res = resp;
33 struct nfs_delegation *delegation;
34 struct inode *inode;
35
36 res->status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
37 if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */
38 goto out;
39
40 memset(res->bitmap, 0, sizeof(res->bitmap));
41 res->status = htonl(NFS4ERR_BADHANDLE);
42
43 dprintk_rcu("NFS: GETATTR callback request from %s\n",
44 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
45
46 inode = nfs_delegation_find_inode(cps->clp, &args->fh);
47 if (IS_ERR(inode)) {
48 if (inode == ERR_PTR(-EAGAIN))
49 res->status = htonl(NFS4ERR_DELAY);
50 trace_nfs4_cb_getattr(cps->clp, &args->fh, NULL,
51 -ntohl(res->status));
52 goto out;
53 }
54 rcu_read_lock();
55 delegation = nfs4_get_valid_delegation(inode);
56 if (delegation == NULL || (delegation->type & FMODE_WRITE) == 0)
57 goto out_iput;
58 res->size = i_size_read(inode);
59 res->change_attr = delegation->change_attr;
60 if (nfs_have_writebacks(inode))
61 res->change_attr++;
62 res->atime = inode_get_atime(inode);
63 res->ctime = inode_get_ctime(inode);
64 res->mtime = inode_get_mtime(inode);
65 res->bitmap[0] = (FATTR4_WORD0_CHANGE | FATTR4_WORD0_SIZE) &
66 args->bitmap[0];
67 res->bitmap[1] = (FATTR4_WORD1_TIME_ACCESS |
68 FATTR4_WORD1_TIME_METADATA |
69 FATTR4_WORD1_TIME_MODIFY) & args->bitmap[1];
70 res->bitmap[2] = (FATTR4_WORD2_TIME_DELEG_ACCESS |
71 FATTR4_WORD2_TIME_DELEG_MODIFY) & args->bitmap[2];
72 res->status = 0;
73out_iput:
74 rcu_read_unlock();
75 trace_nfs4_cb_getattr(cps->clp, &args->fh, inode, -ntohl(res->status));
76 nfs_iput_and_deactive(inode);
77out:
78 dprintk("%s: exit with status = %d\n", __func__, ntohl(res->status));
79 return res->status;
80}
81
82__be32 nfs4_callback_recall(void *argp, void *resp,
83 struct cb_process_state *cps)
84{
85 struct cb_recallargs *args = argp;
86 struct inode *inode;
87 __be32 res;
88
89 res = htonl(NFS4ERR_OP_NOT_IN_SESSION);
90 if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */
91 goto out;
92
93 dprintk_rcu("NFS: RECALL callback request from %s\n",
94 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
95
96 res = htonl(NFS4ERR_BADHANDLE);
97 inode = nfs_delegation_find_inode(cps->clp, &args->fh);
98 if (IS_ERR(inode)) {
99 if (inode == ERR_PTR(-EAGAIN))
100 res = htonl(NFS4ERR_DELAY);
101 trace_nfs4_cb_recall(cps->clp, &args->fh, NULL,
102 &args->stateid, -ntohl(res));
103 goto out;
104 }
105 /* Set up a helper thread to actually return the delegation */
106 switch (nfs_async_inode_return_delegation(inode, &args->stateid)) {
107 case 0:
108 res = 0;
109 break;
110 case -ENOENT:
111 res = htonl(NFS4ERR_BAD_STATEID);
112 break;
113 default:
114 res = htonl(NFS4ERR_RESOURCE);
115 }
116 trace_nfs4_cb_recall(cps->clp, &args->fh, inode,
117 &args->stateid, -ntohl(res));
118 nfs_iput_and_deactive(inode);
119out:
120 dprintk("%s: exit with status = %d\n", __func__, ntohl(res));
121 return res;
122}
123
124#if defined(CONFIG_NFS_V4_1)
125
126/*
127 * Lookup a layout inode by stateid
128 *
129 * Note: returns a refcount on the inode and superblock
130 */
131static struct inode *nfs_layout_find_inode_by_stateid(struct nfs_client *clp,
132 const nfs4_stateid *stateid)
133 __must_hold(RCU)
134{
135 struct nfs_server *server;
136 struct inode *inode;
137 struct pnfs_layout_hdr *lo;
138
139 rcu_read_lock();
140 list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
141 list_for_each_entry_rcu(lo, &server->layouts, plh_layouts) {
142 if (!pnfs_layout_is_valid(lo))
143 continue;
144 if (!nfs4_stateid_match_other(stateid, &lo->plh_stateid))
145 continue;
146 if (nfs_sb_active(server->super))
147 inode = igrab(lo->plh_inode);
148 else
149 inode = ERR_PTR(-EAGAIN);
150 rcu_read_unlock();
151 if (inode)
152 return inode;
153 nfs_sb_deactive(server->super);
154 return ERR_PTR(-EAGAIN);
155 }
156 }
157 rcu_read_unlock();
158 return ERR_PTR(-ENOENT);
159}
160
161/*
162 * Lookup a layout inode by filehandle.
163 *
164 * Note: returns a refcount on the inode and superblock
165 *
166 */
167static struct inode *nfs_layout_find_inode_by_fh(struct nfs_client *clp,
168 const struct nfs_fh *fh)
169{
170 struct nfs_server *server;
171 struct nfs_inode *nfsi;
172 struct inode *inode;
173 struct pnfs_layout_hdr *lo;
174
175 rcu_read_lock();
176 list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
177 list_for_each_entry_rcu(lo, &server->layouts, plh_layouts) {
178 nfsi = NFS_I(lo->plh_inode);
179 if (nfs_compare_fh(fh, &nfsi->fh))
180 continue;
181 if (nfsi->layout != lo)
182 continue;
183 if (nfs_sb_active(server->super))
184 inode = igrab(lo->plh_inode);
185 else
186 inode = ERR_PTR(-EAGAIN);
187 rcu_read_unlock();
188 if (inode)
189 return inode;
190 nfs_sb_deactive(server->super);
191 return ERR_PTR(-EAGAIN);
192 }
193 }
194 rcu_read_unlock();
195 return ERR_PTR(-ENOENT);
196}
197
198static struct inode *nfs_layout_find_inode(struct nfs_client *clp,
199 const struct nfs_fh *fh,
200 const nfs4_stateid *stateid)
201{
202 struct inode *inode;
203
204 inode = nfs_layout_find_inode_by_stateid(clp, stateid);
205 if (inode == ERR_PTR(-ENOENT))
206 inode = nfs_layout_find_inode_by_fh(clp, fh);
207 return inode;
208}
209
210/*
211 * Enforce RFC5661 section 12.5.5.2.1. (Layout Recall and Return Sequencing)
212 */
213static u32 pnfs_check_callback_stateid(struct pnfs_layout_hdr *lo,
214 const nfs4_stateid *new,
215 struct cb_process_state *cps)
216{
217 u32 oldseq, newseq;
218
219 /* Is the stateid not initialised? */
220 if (!pnfs_layout_is_valid(lo))
221 return NFS4ERR_NOMATCHING_LAYOUT;
222
223 /* Mismatched stateid? */
224 if (!nfs4_stateid_match_other(&lo->plh_stateid, new))
225 return NFS4ERR_BAD_STATEID;
226
227 newseq = be32_to_cpu(new->seqid);
228 /* Are we already in a layout recall situation? */
229 if (test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags))
230 return NFS4ERR_DELAY;
231
232 /*
233 * Check that the stateid matches what we think it should be.
234 * Note that if the server sent us a list of referring calls,
235 * and we know that those have completed, then we trust the
236 * stateid argument is correct.
237 */
238 oldseq = be32_to_cpu(lo->plh_stateid.seqid);
239 if (newseq > oldseq + 1 && !cps->referring_calls)
240 return NFS4ERR_DELAY;
241
242 /* Crazy server! */
243 if (newseq <= oldseq)
244 return NFS4ERR_OLD_STATEID;
245
246 return NFS_OK;
247}
248
249static u32 initiate_file_draining(struct nfs_client *clp,
250 struct cb_layoutrecallargs *args,
251 struct cb_process_state *cps)
252{
253 struct inode *ino;
254 struct pnfs_layout_hdr *lo;
255 u32 rv = NFS4ERR_NOMATCHING_LAYOUT;
256 LIST_HEAD(free_me_list);
257
258 ino = nfs_layout_find_inode(clp, &args->cbl_fh, &args->cbl_stateid);
259 if (IS_ERR(ino)) {
260 if (ino == ERR_PTR(-EAGAIN))
261 rv = NFS4ERR_DELAY;
262 goto out_noput;
263 }
264
265 pnfs_layoutcommit_inode(ino, false);
266
267
268 spin_lock(&ino->i_lock);
269 lo = NFS_I(ino)->layout;
270 if (!lo) {
271 spin_unlock(&ino->i_lock);
272 goto out;
273 }
274 pnfs_get_layout_hdr(lo);
275 rv = pnfs_check_callback_stateid(lo, &args->cbl_stateid, cps);
276 if (rv != NFS_OK)
277 goto unlock;
278
279 /*
280 * Enforce RFC5661 Section 12.5.5.2.1.5 (Bulk Recall and Return)
281 */
282 if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
283 rv = NFS4ERR_DELAY;
284 goto unlock;
285 }
286
287 pnfs_set_layout_stateid(lo, &args->cbl_stateid, NULL, true);
288 switch (pnfs_mark_matching_lsegs_return(lo, &free_me_list,
289 &args->cbl_range,
290 be32_to_cpu(args->cbl_stateid.seqid))) {
291 case 0:
292 case -EBUSY:
293 /* There are layout segments that need to be returned */
294 rv = NFS4_OK;
295 break;
296 case -ENOENT:
297 set_bit(NFS_LAYOUT_DRAIN, &lo->plh_flags);
298 /* Embrace your forgetfulness! */
299 rv = NFS4ERR_NOMATCHING_LAYOUT;
300
301 if (NFS_SERVER(ino)->pnfs_curr_ld->return_range) {
302 NFS_SERVER(ino)->pnfs_curr_ld->return_range(lo,
303 &args->cbl_range);
304 }
305 }
306unlock:
307 spin_unlock(&ino->i_lock);
308 pnfs_free_lseg_list(&free_me_list);
309 /* Free all lsegs that are attached to commit buckets */
310 nfs_commit_inode(ino, 0);
311 pnfs_put_layout_hdr(lo);
312out:
313 nfs_iput_and_deactive(ino);
314out_noput:
315 trace_nfs4_cb_layoutrecall_file(clp, &args->cbl_fh, ino,
316 &args->cbl_stateid, -rv);
317 return rv;
318}
319
320static u32 initiate_bulk_draining(struct nfs_client *clp,
321 struct cb_layoutrecallargs *args)
322{
323 int stat;
324
325 if (args->cbl_recall_type == RETURN_FSID)
326 stat = pnfs_layout_destroy_byfsid(clp, &args->cbl_fsid,
327 PNFS_LAYOUT_BULK_RETURN);
328 else
329 stat = pnfs_layout_destroy_byclid(clp, PNFS_LAYOUT_BULK_RETURN);
330 if (stat != 0)
331 return NFS4ERR_DELAY;
332 return NFS4ERR_NOMATCHING_LAYOUT;
333}
334
335static u32 do_callback_layoutrecall(struct nfs_client *clp,
336 struct cb_layoutrecallargs *args,
337 struct cb_process_state *cps)
338{
339 if (args->cbl_recall_type == RETURN_FILE)
340 return initiate_file_draining(clp, args, cps);
341 return initiate_bulk_draining(clp, args);
342}
343
344__be32 nfs4_callback_layoutrecall(void *argp, void *resp,
345 struct cb_process_state *cps)
346{
347 struct cb_layoutrecallargs *args = argp;
348 u32 res = NFS4ERR_OP_NOT_IN_SESSION;
349
350 if (cps->clp)
351 res = do_callback_layoutrecall(cps->clp, args, cps);
352 return cpu_to_be32(res);
353}
354
355static void pnfs_recall_all_layouts(struct nfs_client *clp,
356 struct cb_process_state *cps)
357{
358 struct cb_layoutrecallargs args;
359
360 /* Pretend we got a CB_LAYOUTRECALL(ALL) */
361 memset(&args, 0, sizeof(args));
362 args.cbl_recall_type = RETURN_ALL;
363 /* FIXME we ignore errors, what should we do? */
364 do_callback_layoutrecall(clp, &args, cps);
365}
366
367__be32 nfs4_callback_devicenotify(void *argp, void *resp,
368 struct cb_process_state *cps)
369{
370 struct cb_devicenotifyargs *args = argp;
371 const struct pnfs_layoutdriver_type *ld = NULL;
372 uint32_t i;
373 __be32 res = 0;
374
375 if (!cps->clp) {
376 res = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION);
377 goto out;
378 }
379
380 for (i = 0; i < args->ndevs; i++) {
381 struct cb_devicenotifyitem *dev = &args->devs[i];
382
383 if (!ld || ld->id != dev->cbd_layout_type) {
384 pnfs_put_layoutdriver(ld);
385 ld = pnfs_find_layoutdriver(dev->cbd_layout_type);
386 if (!ld)
387 continue;
388 }
389 nfs4_delete_deviceid(ld, cps->clp, &dev->cbd_dev_id);
390 }
391 pnfs_put_layoutdriver(ld);
392out:
393 kfree(args->devs);
394 return res;
395}
396
397/*
398 * Validate the sequenceID sent by the server.
399 * Return success if the sequenceID is one more than what we last saw on
400 * this slot, accounting for wraparound. Increments the slot's sequence.
401 *
402 * We don't yet implement a duplicate request cache, instead we set the
403 * back channel ca_maxresponsesize_cached to zero. This is OK for now
404 * since we only currently implement idempotent callbacks anyway.
405 *
406 * We have a single slot backchannel at this time, so we don't bother
407 * checking the used_slots bit array on the table. The lower layer guarantees
408 * a single outstanding callback request at a time.
409 */
410static __be32
411validate_seqid(const struct nfs4_slot_table *tbl, const struct nfs4_slot *slot,
412 const struct cb_sequenceargs * args)
413{
414 __be32 ret;
415
416 ret = cpu_to_be32(NFS4ERR_BADSLOT);
417 if (args->csa_slotid > tbl->server_highest_slotid)
418 goto out_err;
419
420 /* Replay */
421 if (args->csa_sequenceid == slot->seq_nr) {
422 ret = cpu_to_be32(NFS4ERR_DELAY);
423 if (nfs4_test_locked_slot(tbl, slot->slot_nr))
424 goto out_err;
425
426 /* Signal process_op to set this error on next op */
427 ret = cpu_to_be32(NFS4ERR_RETRY_UNCACHED_REP);
428 if (args->csa_cachethis == 0)
429 goto out_err;
430
431 /* Liar! We never allowed you to set csa_cachethis != 0 */
432 ret = cpu_to_be32(NFS4ERR_SEQ_FALSE_RETRY);
433 goto out_err;
434 }
435
436 /* Note: wraparound relies on seq_nr being of type u32 */
437 /* Misordered request */
438 ret = cpu_to_be32(NFS4ERR_SEQ_MISORDERED);
439 if (args->csa_sequenceid != slot->seq_nr + 1)
440 goto out_err;
441
442 return cpu_to_be32(NFS4_OK);
443
444out_err:
445 trace_nfs4_cb_seqid_err(args, ret);
446 return ret;
447}
448
449/*
450 * For each referring call triple, check the session's slot table for
451 * a match. If the slot is in use and the sequence numbers match, the
452 * client is still waiting for a response to the original request.
453 */
454static int referring_call_exists(struct nfs_client *clp,
455 uint32_t nrclists,
456 struct referring_call_list *rclists,
457 spinlock_t *lock)
458 __releases(lock)
459 __acquires(lock)
460{
461 int status = 0;
462 int found = 0;
463 int i, j;
464 struct nfs4_session *session;
465 struct nfs4_slot_table *tbl;
466 struct referring_call_list *rclist;
467 struct referring_call *ref;
468
469 /*
470 * XXX When client trunking is implemented, this becomes
471 * a session lookup from within the loop
472 */
473 session = clp->cl_session;
474 tbl = &session->fc_slot_table;
475
476 for (i = 0; i < nrclists; i++) {
477 rclist = &rclists[i];
478 if (memcmp(session->sess_id.data,
479 rclist->rcl_sessionid.data,
480 NFS4_MAX_SESSIONID_LEN) != 0)
481 continue;
482
483 for (j = 0; j < rclist->rcl_nrefcalls; j++) {
484 ref = &rclist->rcl_refcalls[j];
485 spin_unlock(lock);
486 status = nfs4_slot_wait_on_seqid(tbl, ref->rc_slotid,
487 ref->rc_sequenceid, HZ >> 1) < 0;
488 spin_lock(lock);
489 if (status)
490 goto out;
491 found++;
492 }
493 }
494
495out:
496 return status < 0 ? status : found;
497}
498
499__be32 nfs4_callback_sequence(void *argp, void *resp,
500 struct cb_process_state *cps)
501{
502 struct cb_sequenceargs *args = argp;
503 struct cb_sequenceres *res = resp;
504 struct nfs4_slot_table *tbl;
505 struct nfs4_slot *slot;
506 struct nfs_client *clp;
507 int ret;
508 int i;
509 __be32 status = htonl(NFS4ERR_BADSESSION);
510
511 clp = nfs4_find_client_sessionid(cps->net, args->csa_addr,
512 &args->csa_sessionid, cps->minorversion);
513 if (clp == NULL)
514 goto out;
515
516 if (!(clp->cl_session->flags & SESSION4_BACK_CHAN))
517 goto out;
518
519 tbl = &clp->cl_session->bc_slot_table;
520
521 /* Set up res before grabbing the spinlock */
522 memcpy(&res->csr_sessionid, &args->csa_sessionid,
523 sizeof(res->csr_sessionid));
524 res->csr_sequenceid = args->csa_sequenceid;
525 res->csr_slotid = args->csa_slotid;
526
527 spin_lock(&tbl->slot_tbl_lock);
528 /* state manager is resetting the session */
529 if (test_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state)) {
530 status = htonl(NFS4ERR_DELAY);
531 /* Return NFS4ERR_BADSESSION if we're draining the session
532 * in order to reset it.
533 */
534 if (test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
535 status = htonl(NFS4ERR_BADSESSION);
536 goto out_unlock;
537 }
538
539 status = htonl(NFS4ERR_BADSLOT);
540 slot = nfs4_lookup_slot(tbl, args->csa_slotid);
541 if (IS_ERR(slot))
542 goto out_unlock;
543
544 res->csr_highestslotid = tbl->server_highest_slotid;
545 res->csr_target_highestslotid = tbl->target_highest_slotid;
546
547 status = validate_seqid(tbl, slot, args);
548 if (status)
549 goto out_unlock;
550 if (!nfs4_try_to_lock_slot(tbl, slot)) {
551 status = htonl(NFS4ERR_DELAY);
552 goto out_unlock;
553 }
554 cps->slot = slot;
555
556 /* The ca_maxresponsesize_cached is 0 with no DRC */
557 if (args->csa_cachethis != 0) {
558 status = htonl(NFS4ERR_REP_TOO_BIG_TO_CACHE);
559 goto out_unlock;
560 }
561
562 /*
563 * Check for pending referring calls. If a match is found, a
564 * related callback was received before the response to the original
565 * call.
566 */
567 ret = referring_call_exists(clp, args->csa_nrclists, args->csa_rclists,
568 &tbl->slot_tbl_lock);
569 if (ret < 0) {
570 status = htonl(NFS4ERR_DELAY);
571 goto out_unlock;
572 }
573 cps->referring_calls = ret;
574
575 /*
576 * RFC5661 20.9.3
577 * If CB_SEQUENCE returns an error, then the state of the slot
578 * (sequence ID, cached reply) MUST NOT change.
579 */
580 slot->seq_nr = args->csa_sequenceid;
581out_unlock:
582 spin_unlock(&tbl->slot_tbl_lock);
583
584out:
585 cps->clp = clp; /* put in nfs4_callback_compound */
586 for (i = 0; i < args->csa_nrclists; i++)
587 kfree(args->csa_rclists[i].rcl_refcalls);
588 kfree(args->csa_rclists);
589
590 if (status == htonl(NFS4ERR_RETRY_UNCACHED_REP)) {
591 cps->drc_status = status;
592 status = 0;
593 } else
594 res->csr_status = status;
595
596 trace_nfs4_cb_sequence(args, res, status);
597 return status;
598}
599
600static bool
601validate_bitmap_values(unsigned int mask)
602{
603 return (mask & ~RCA4_TYPE_MASK_ALL) == 0;
604}
605
606__be32 nfs4_callback_recallany(void *argp, void *resp,
607 struct cb_process_state *cps)
608{
609 struct cb_recallanyargs *args = argp;
610 __be32 status;
611 fmode_t flags = 0;
612 bool schedule_manager = false;
613
614 status = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION);
615 if (!cps->clp) /* set in cb_sequence */
616 goto out;
617
618 dprintk_rcu("NFS: RECALL_ANY callback request from %s\n",
619 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
620
621 status = cpu_to_be32(NFS4ERR_INVAL);
622 if (!validate_bitmap_values(args->craa_type_mask))
623 goto out;
624
625 status = cpu_to_be32(NFS4_OK);
626 if (args->craa_type_mask & BIT(RCA4_TYPE_MASK_RDATA_DLG))
627 flags = FMODE_READ;
628 if (args->craa_type_mask & BIT(RCA4_TYPE_MASK_WDATA_DLG))
629 flags |= FMODE_WRITE;
630 if (flags)
631 nfs_expire_unused_delegation_types(cps->clp, flags);
632
633 if (args->craa_type_mask & BIT(RCA4_TYPE_MASK_FILE_LAYOUT))
634 pnfs_recall_all_layouts(cps->clp, cps);
635
636 if (args->craa_type_mask & BIT(PNFS_FF_RCA4_TYPE_MASK_READ)) {
637 set_bit(NFS4CLNT_RECALL_ANY_LAYOUT_READ, &cps->clp->cl_state);
638 schedule_manager = true;
639 }
640 if (args->craa_type_mask & BIT(PNFS_FF_RCA4_TYPE_MASK_RW)) {
641 set_bit(NFS4CLNT_RECALL_ANY_LAYOUT_RW, &cps->clp->cl_state);
642 schedule_manager = true;
643 }
644 if (schedule_manager)
645 nfs4_schedule_state_manager(cps->clp);
646
647out:
648 dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
649 return status;
650}
651
652/* Reduce the fore channel's max_slots to the target value */
653__be32 nfs4_callback_recallslot(void *argp, void *resp,
654 struct cb_process_state *cps)
655{
656 struct cb_recallslotargs *args = argp;
657 struct nfs4_slot_table *fc_tbl;
658 __be32 status;
659
660 status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
661 if (!cps->clp) /* set in cb_sequence */
662 goto out;
663
664 dprintk_rcu("NFS: CB_RECALL_SLOT request from %s target highest slotid %u\n",
665 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR),
666 args->crsa_target_highest_slotid);
667
668 fc_tbl = &cps->clp->cl_session->fc_slot_table;
669
670 status = htonl(NFS4_OK);
671
672 nfs41_set_target_slotid(fc_tbl, args->crsa_target_highest_slotid);
673 nfs41_notify_server(cps->clp);
674out:
675 dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
676 return status;
677}
678
679__be32 nfs4_callback_notify_lock(void *argp, void *resp,
680 struct cb_process_state *cps)
681{
682 struct cb_notify_lock_args *args = argp;
683
684 if (!cps->clp) /* set in cb_sequence */
685 return htonl(NFS4ERR_OP_NOT_IN_SESSION);
686
687 dprintk_rcu("NFS: CB_NOTIFY_LOCK request from %s\n",
688 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
689
690 /* Don't wake anybody if the string looked bogus */
691 if (args->cbnl_valid)
692 __wake_up(&cps->clp->cl_lock_waitq, TASK_NORMAL, 0, args);
693
694 return htonl(NFS4_OK);
695}
696#endif /* CONFIG_NFS_V4_1 */
697#ifdef CONFIG_NFS_V4_2
698static void nfs4_copy_cb_args(struct nfs4_copy_state *cp_state,
699 struct cb_offloadargs *args)
700{
701 cp_state->count = args->wr_count;
702 cp_state->error = args->error;
703 if (!args->error) {
704 cp_state->verf.committed = args->wr_writeverf.committed;
705 memcpy(&cp_state->verf.verifier.data[0],
706 &args->wr_writeverf.verifier.data[0],
707 NFS4_VERIFIER_SIZE);
708 }
709}
710
711__be32 nfs4_callback_offload(void *data, void *dummy,
712 struct cb_process_state *cps)
713{
714 struct cb_offloadargs *args = data;
715 struct nfs_server *server;
716 struct nfs4_copy_state *copy, *tmp_copy;
717 bool found = false;
718
719 copy = kzalloc(sizeof(struct nfs4_copy_state), GFP_KERNEL);
720 if (!copy)
721 return htonl(NFS4ERR_SERVERFAULT);
722
723 spin_lock(&cps->clp->cl_lock);
724 rcu_read_lock();
725 list_for_each_entry_rcu(server, &cps->clp->cl_superblocks,
726 client_link) {
727 list_for_each_entry(tmp_copy, &server->ss_copies, copies) {
728 if (memcmp(args->coa_stateid.other,
729 tmp_copy->stateid.other,
730 sizeof(args->coa_stateid.other)))
731 continue;
732 nfs4_copy_cb_args(tmp_copy, args);
733 complete(&tmp_copy->completion);
734 found = true;
735 goto out;
736 }
737 }
738out:
739 rcu_read_unlock();
740 if (!found) {
741 memcpy(©->stateid, &args->coa_stateid, NFS4_STATEID_SIZE);
742 nfs4_copy_cb_args(copy, args);
743 list_add_tail(©->copies, &cps->clp->pending_cb_stateids);
744 } else
745 kfree(copy);
746 spin_unlock(&cps->clp->cl_lock);
747
748 trace_nfs4_cb_offload(&args->coa_fh, &args->coa_stateid,
749 args->wr_count, args->error,
750 args->wr_writeverf.committed);
751 return 0;
752}
753#endif /* CONFIG_NFS_V4_2 */