Merge tag 'writeback_for_v5.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux-2.6-microblaze.git] / fs / nfs / callback_proc.c
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 #include <linux/nfs4.h>
10 #include <linux/nfs_fs.h>
11 #include <linux/slab.h>
12 #include <linux/rcupdate.h>
13 #include "nfs4_fs.h"
14 #include "callback.h"
15 #include "delegation.h"
16 #include "internal.h"
17 #include "pnfs.h"
18 #include "nfs4session.h"
19 #include "nfs4trace.h"
20
21 #define NFSDBG_FACILITY NFSDBG_CALLBACK
22
23 __be32 nfs4_callback_getattr(void *argp, void *resp,
24                              struct cb_process_state *cps)
25 {
26         struct cb_getattrargs *args = argp;
27         struct cb_getattrres *res = resp;
28         struct nfs_delegation *delegation;
29         struct inode *inode;
30
31         res->status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
32         if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */
33                 goto out;
34
35         res->bitmap[0] = res->bitmap[1] = 0;
36         res->status = htonl(NFS4ERR_BADHANDLE);
37
38         dprintk_rcu("NFS: GETATTR callback request from %s\n",
39                 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
40
41         inode = nfs_delegation_find_inode(cps->clp, &args->fh);
42         if (IS_ERR(inode)) {
43                 if (inode == ERR_PTR(-EAGAIN))
44                         res->status = htonl(NFS4ERR_DELAY);
45                 trace_nfs4_cb_getattr(cps->clp, &args->fh, NULL,
46                                 -ntohl(res->status));
47                 goto out;
48         }
49         rcu_read_lock();
50         delegation = nfs4_get_valid_delegation(inode);
51         if (delegation == NULL || (delegation->type & FMODE_WRITE) == 0)
52                 goto out_iput;
53         res->size = i_size_read(inode);
54         res->change_attr = delegation->change_attr;
55         if (nfs_have_writebacks(inode))
56                 res->change_attr++;
57         res->ctime = inode->i_ctime;
58         res->mtime = inode->i_mtime;
59         res->bitmap[0] = (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE) &
60                 args->bitmap[0];
61         res->bitmap[1] = (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY) &
62                 args->bitmap[1];
63         res->status = 0;
64 out_iput:
65         rcu_read_unlock();
66         trace_nfs4_cb_getattr(cps->clp, &args->fh, inode, -ntohl(res->status));
67         nfs_iput_and_deactive(inode);
68 out:
69         dprintk("%s: exit with status = %d\n", __func__, ntohl(res->status));
70         return res->status;
71 }
72
73 __be32 nfs4_callback_recall(void *argp, void *resp,
74                             struct cb_process_state *cps)
75 {
76         struct cb_recallargs *args = argp;
77         struct inode *inode;
78         __be32 res;
79         
80         res = htonl(NFS4ERR_OP_NOT_IN_SESSION);
81         if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */
82                 goto out;
83
84         dprintk_rcu("NFS: RECALL callback request from %s\n",
85                 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
86
87         res = htonl(NFS4ERR_BADHANDLE);
88         inode = nfs_delegation_find_inode(cps->clp, &args->fh);
89         if (IS_ERR(inode)) {
90                 if (inode == ERR_PTR(-EAGAIN))
91                         res = htonl(NFS4ERR_DELAY);
92                 trace_nfs4_cb_recall(cps->clp, &args->fh, NULL,
93                                 &args->stateid, -ntohl(res));
94                 goto out;
95         }
96         /* Set up a helper thread to actually return the delegation */
97         switch (nfs_async_inode_return_delegation(inode, &args->stateid)) {
98         case 0:
99                 res = 0;
100                 break;
101         case -ENOENT:
102                 res = htonl(NFS4ERR_BAD_STATEID);
103                 break;
104         default:
105                 res = htonl(NFS4ERR_RESOURCE);
106         }
107         trace_nfs4_cb_recall(cps->clp, &args->fh, inode,
108                         &args->stateid, -ntohl(res));
109         nfs_iput_and_deactive(inode);
110 out:
111         dprintk("%s: exit with status = %d\n", __func__, ntohl(res));
112         return res;
113 }
114
115 #if defined(CONFIG_NFS_V4_1)
116
117 /*
118  * Lookup a layout inode by stateid
119  *
120  * Note: returns a refcount on the inode and superblock
121  */
122 static struct inode *nfs_layout_find_inode_by_stateid(struct nfs_client *clp,
123                 const nfs4_stateid *stateid)
124         __must_hold(RCU)
125 {
126         struct nfs_server *server;
127         struct inode *inode;
128         struct pnfs_layout_hdr *lo;
129
130         rcu_read_lock();
131         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
132                 list_for_each_entry_rcu(lo, &server->layouts, plh_layouts) {
133                         if (!pnfs_layout_is_valid(lo))
134                                 continue;
135                         if (stateid != NULL &&
136                             !nfs4_stateid_match_other(stateid, &lo->plh_stateid))
137                                 continue;
138                         if (!nfs_sb_active(server->super))
139                                 continue;
140                         inode = igrab(lo->plh_inode);
141                         rcu_read_unlock();
142                         if (inode)
143                                 return inode;
144                         nfs_sb_deactive(server->super);
145                         return ERR_PTR(-EAGAIN);
146                 }
147         }
148         rcu_read_unlock();
149         return ERR_PTR(-ENOENT);
150 }
151
152 /*
153  * Lookup a layout inode by filehandle.
154  *
155  * Note: returns a refcount on the inode and superblock
156  *
157  */
158 static struct inode *nfs_layout_find_inode_by_fh(struct nfs_client *clp,
159                 const struct nfs_fh *fh)
160 {
161         struct nfs_server *server;
162         struct nfs_inode *nfsi;
163         struct inode *inode;
164         struct pnfs_layout_hdr *lo;
165
166         rcu_read_lock();
167         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
168                 list_for_each_entry_rcu(lo, &server->layouts, plh_layouts) {
169                         nfsi = NFS_I(lo->plh_inode);
170                         if (nfs_compare_fh(fh, &nfsi->fh))
171                                 continue;
172                         if (nfsi->layout != lo)
173                                 continue;
174                         if (!nfs_sb_active(server->super))
175                                 continue;
176                         inode = igrab(lo->plh_inode);
177                         rcu_read_unlock();
178                         if (inode)
179                                 return inode;
180                         nfs_sb_deactive(server->super);
181                         return ERR_PTR(-EAGAIN);
182                 }
183         }
184         rcu_read_unlock();
185         return ERR_PTR(-ENOENT);
186 }
187
188 static struct inode *nfs_layout_find_inode(struct nfs_client *clp,
189                 const struct nfs_fh *fh,
190                 const nfs4_stateid *stateid)
191 {
192         struct inode *inode;
193
194         inode = nfs_layout_find_inode_by_stateid(clp, stateid);
195         if (inode == ERR_PTR(-ENOENT))
196                 inode = nfs_layout_find_inode_by_fh(clp, fh);
197         return inode;
198 }
199
200 /*
201  * Enforce RFC5661 section 12.5.5.2.1. (Layout Recall and Return Sequencing)
202  */
203 static u32 pnfs_check_callback_stateid(struct pnfs_layout_hdr *lo,
204                                         const nfs4_stateid *new)
205 {
206         u32 oldseq, newseq;
207
208         /* Is the stateid not initialised? */
209         if (!pnfs_layout_is_valid(lo))
210                 return NFS4ERR_NOMATCHING_LAYOUT;
211
212         /* Mismatched stateid? */
213         if (!nfs4_stateid_match_other(&lo->plh_stateid, new))
214                 return NFS4ERR_BAD_STATEID;
215
216         newseq = be32_to_cpu(new->seqid);
217         /* Are we already in a layout recall situation? */
218         if (test_bit(NFS_LAYOUT_RETURN_REQUESTED, &lo->plh_flags) &&
219             lo->plh_return_seq != 0) {
220                 if (newseq < lo->plh_return_seq)
221                         return NFS4ERR_OLD_STATEID;
222                 if (newseq > lo->plh_return_seq)
223                         return NFS4ERR_DELAY;
224                 goto out;
225         }
226
227         /* Check that the stateid matches what we think it should be. */
228         oldseq = be32_to_cpu(lo->plh_stateid.seqid);
229         if (newseq > oldseq + 1)
230                 return NFS4ERR_DELAY;
231         /* Crazy server! */
232         if (newseq <= oldseq)
233                 return NFS4ERR_OLD_STATEID;
234 out:
235         return NFS_OK;
236 }
237
238 static u32 initiate_file_draining(struct nfs_client *clp,
239                                   struct cb_layoutrecallargs *args)
240 {
241         struct inode *ino;
242         struct pnfs_layout_hdr *lo;
243         u32 rv = NFS4ERR_NOMATCHING_LAYOUT;
244         LIST_HEAD(free_me_list);
245
246         ino = nfs_layout_find_inode(clp, &args->cbl_fh, &args->cbl_stateid);
247         if (IS_ERR(ino)) {
248                 if (ino == ERR_PTR(-EAGAIN))
249                         rv = NFS4ERR_DELAY;
250                 goto out_noput;
251         }
252
253         pnfs_layoutcommit_inode(ino, false);
254
255
256         spin_lock(&ino->i_lock);
257         lo = NFS_I(ino)->layout;
258         if (!lo) {
259                 spin_unlock(&ino->i_lock);
260                 goto out;
261         }
262         pnfs_get_layout_hdr(lo);
263         rv = pnfs_check_callback_stateid(lo, &args->cbl_stateid);
264         if (rv != NFS_OK)
265                 goto unlock;
266
267         /*
268          * Enforce RFC5661 Section 12.5.5.2.1.5 (Bulk Recall and Return)
269          */
270         if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
271                 rv = NFS4ERR_DELAY;
272                 goto unlock;
273         }
274
275         pnfs_set_layout_stateid(lo, &args->cbl_stateid, NULL, true);
276         switch (pnfs_mark_matching_lsegs_return(lo, &free_me_list,
277                                 &args->cbl_range,
278                                 be32_to_cpu(args->cbl_stateid.seqid))) {
279         case 0:
280         case -EBUSY:
281                 /* There are layout segments that need to be returned */
282                 rv = NFS4_OK;
283                 break;
284         case -ENOENT:
285                 /* Embrace your forgetfulness! */
286                 rv = NFS4ERR_NOMATCHING_LAYOUT;
287
288                 if (NFS_SERVER(ino)->pnfs_curr_ld->return_range) {
289                         NFS_SERVER(ino)->pnfs_curr_ld->return_range(lo,
290                                 &args->cbl_range);
291                 }
292         }
293 unlock:
294         spin_unlock(&ino->i_lock);
295         pnfs_free_lseg_list(&free_me_list);
296         /* Free all lsegs that are attached to commit buckets */
297         nfs_commit_inode(ino, 0);
298         pnfs_put_layout_hdr(lo);
299 out:
300         nfs_iput_and_deactive(ino);
301 out_noput:
302         trace_nfs4_cb_layoutrecall_file(clp, &args->cbl_fh, ino,
303                         &args->cbl_stateid, -rv);
304         return rv;
305 }
306
307 static u32 initiate_bulk_draining(struct nfs_client *clp,
308                                   struct cb_layoutrecallargs *args)
309 {
310         int stat;
311
312         if (args->cbl_recall_type == RETURN_FSID)
313                 stat = pnfs_destroy_layouts_byfsid(clp, &args->cbl_fsid, true);
314         else
315                 stat = pnfs_destroy_layouts_byclid(clp, true);
316         if (stat != 0)
317                 return NFS4ERR_DELAY;
318         return NFS4ERR_NOMATCHING_LAYOUT;
319 }
320
321 static u32 do_callback_layoutrecall(struct nfs_client *clp,
322                                     struct cb_layoutrecallargs *args)
323 {
324         if (args->cbl_recall_type == RETURN_FILE)
325                 return initiate_file_draining(clp, args);
326         return initiate_bulk_draining(clp, args);
327 }
328
329 __be32 nfs4_callback_layoutrecall(void *argp, void *resp,
330                                   struct cb_process_state *cps)
331 {
332         struct cb_layoutrecallargs *args = argp;
333         u32 res = NFS4ERR_OP_NOT_IN_SESSION;
334
335         if (cps->clp)
336                 res = do_callback_layoutrecall(cps->clp, args);
337         return cpu_to_be32(res);
338 }
339
340 static void pnfs_recall_all_layouts(struct nfs_client *clp)
341 {
342         struct cb_layoutrecallargs args;
343
344         /* Pretend we got a CB_LAYOUTRECALL(ALL) */
345         memset(&args, 0, sizeof(args));
346         args.cbl_recall_type = RETURN_ALL;
347         /* FIXME we ignore errors, what should we do? */
348         do_callback_layoutrecall(clp, &args);
349 }
350
351 __be32 nfs4_callback_devicenotify(void *argp, void *resp,
352                                   struct cb_process_state *cps)
353 {
354         struct cb_devicenotifyargs *args = argp;
355         int i;
356         __be32 res = 0;
357         struct nfs_client *clp = cps->clp;
358         struct nfs_server *server = NULL;
359
360         if (!clp) {
361                 res = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION);
362                 goto out;
363         }
364
365         for (i = 0; i < args->ndevs; i++) {
366                 struct cb_devicenotifyitem *dev = &args->devs[i];
367
368                 if (!server ||
369                     server->pnfs_curr_ld->id != dev->cbd_layout_type) {
370                         rcu_read_lock();
371                         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
372                                 if (server->pnfs_curr_ld &&
373                                     server->pnfs_curr_ld->id == dev->cbd_layout_type) {
374                                         rcu_read_unlock();
375                                         goto found;
376                                 }
377                         rcu_read_unlock();
378                         continue;
379                 }
380
381         found:
382                 nfs4_delete_deviceid(server->pnfs_curr_ld, clp, &dev->cbd_dev_id);
383         }
384
385 out:
386         kfree(args->devs);
387         return res;
388 }
389
390 /*
391  * Validate the sequenceID sent by the server.
392  * Return success if the sequenceID is one more than what we last saw on
393  * this slot, accounting for wraparound.  Increments the slot's sequence.
394  *
395  * We don't yet implement a duplicate request cache, instead we set the
396  * back channel ca_maxresponsesize_cached to zero. This is OK for now
397  * since we only currently implement idempotent callbacks anyway.
398  *
399  * We have a single slot backchannel at this time, so we don't bother
400  * checking the used_slots bit array on the table.  The lower layer guarantees
401  * a single outstanding callback request at a time.
402  */
403 static __be32
404 validate_seqid(const struct nfs4_slot_table *tbl, const struct nfs4_slot *slot,
405                 const struct cb_sequenceargs * args)
406 {
407         __be32 ret;
408
409         ret = cpu_to_be32(NFS4ERR_BADSLOT);
410         if (args->csa_slotid > tbl->server_highest_slotid)
411                 goto out_err;
412
413         /* Replay */
414         if (args->csa_sequenceid == slot->seq_nr) {
415                 ret = cpu_to_be32(NFS4ERR_DELAY);
416                 if (nfs4_test_locked_slot(tbl, slot->slot_nr))
417                         goto out_err;
418
419                 /* Signal process_op to set this error on next op */
420                 ret = cpu_to_be32(NFS4ERR_RETRY_UNCACHED_REP);
421                 if (args->csa_cachethis == 0)
422                         goto out_err;
423
424                 /* Liar! We never allowed you to set csa_cachethis != 0 */
425                 ret = cpu_to_be32(NFS4ERR_SEQ_FALSE_RETRY);
426                 goto out_err;
427         }
428
429         /* Note: wraparound relies on seq_nr being of type u32 */
430         /* Misordered request */
431         ret = cpu_to_be32(NFS4ERR_SEQ_MISORDERED);
432         if (args->csa_sequenceid != slot->seq_nr + 1)
433                 goto out_err;
434
435         return cpu_to_be32(NFS4_OK);
436
437 out_err:
438         trace_nfs4_cb_seqid_err(args, ret);
439         return ret;
440 }
441
442 /*
443  * For each referring call triple, check the session's slot table for
444  * a match.  If the slot is in use and the sequence numbers match, the
445  * client is still waiting for a response to the original request.
446  */
447 static int referring_call_exists(struct nfs_client *clp,
448                                   uint32_t nrclists,
449                                   struct referring_call_list *rclists,
450                                   spinlock_t *lock)
451         __releases(lock)
452         __acquires(lock)
453 {
454         int status = 0;
455         int i, j;
456         struct nfs4_session *session;
457         struct nfs4_slot_table *tbl;
458         struct referring_call_list *rclist;
459         struct referring_call *ref;
460
461         /*
462          * XXX When client trunking is implemented, this becomes
463          * a session lookup from within the loop
464          */
465         session = clp->cl_session;
466         tbl = &session->fc_slot_table;
467
468         for (i = 0; i < nrclists; i++) {
469                 rclist = &rclists[i];
470                 if (memcmp(session->sess_id.data,
471                            rclist->rcl_sessionid.data,
472                            NFS4_MAX_SESSIONID_LEN) != 0)
473                         continue;
474
475                 for (j = 0; j < rclist->rcl_nrefcalls; j++) {
476                         ref = &rclist->rcl_refcalls[j];
477                         spin_unlock(lock);
478                         status = nfs4_slot_wait_on_seqid(tbl, ref->rc_slotid,
479                                         ref->rc_sequenceid, HZ >> 1) < 0;
480                         spin_lock(lock);
481                         if (status)
482                                 goto out;
483                 }
484         }
485
486 out:
487         return status;
488 }
489
490 __be32 nfs4_callback_sequence(void *argp, void *resp,
491                               struct cb_process_state *cps)
492 {
493         struct cb_sequenceargs *args = argp;
494         struct cb_sequenceres *res = resp;
495         struct nfs4_slot_table *tbl;
496         struct nfs4_slot *slot;
497         struct nfs_client *clp;
498         int i;
499         __be32 status = htonl(NFS4ERR_BADSESSION);
500
501         clp = nfs4_find_client_sessionid(cps->net, args->csa_addr,
502                                          &args->csa_sessionid, cps->minorversion);
503         if (clp == NULL)
504                 goto out;
505
506         if (!(clp->cl_session->flags & SESSION4_BACK_CHAN))
507                 goto out;
508
509         tbl = &clp->cl_session->bc_slot_table;
510
511         /* Set up res before grabbing the spinlock */
512         memcpy(&res->csr_sessionid, &args->csa_sessionid,
513                sizeof(res->csr_sessionid));
514         res->csr_sequenceid = args->csa_sequenceid;
515         res->csr_slotid = args->csa_slotid;
516
517         spin_lock(&tbl->slot_tbl_lock);
518         /* state manager is resetting the session */
519         if (test_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state)) {
520                 status = htonl(NFS4ERR_DELAY);
521                 /* Return NFS4ERR_BADSESSION if we're draining the session
522                  * in order to reset it.
523                  */
524                 if (test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
525                         status = htonl(NFS4ERR_BADSESSION);
526                 goto out_unlock;
527         }
528
529         status = htonl(NFS4ERR_BADSLOT);
530         slot = nfs4_lookup_slot(tbl, args->csa_slotid);
531         if (IS_ERR(slot))
532                 goto out_unlock;
533
534         res->csr_highestslotid = tbl->server_highest_slotid;
535         res->csr_target_highestslotid = tbl->target_highest_slotid;
536
537         status = validate_seqid(tbl, slot, args);
538         if (status)
539                 goto out_unlock;
540         if (!nfs4_try_to_lock_slot(tbl, slot)) {
541                 status = htonl(NFS4ERR_DELAY);
542                 goto out_unlock;
543         }
544         cps->slot = slot;
545
546         /* The ca_maxresponsesize_cached is 0 with no DRC */
547         if (args->csa_cachethis != 0) {
548                 status = htonl(NFS4ERR_REP_TOO_BIG_TO_CACHE);
549                 goto out_unlock;
550         }
551
552         /*
553          * Check for pending referring calls.  If a match is found, a
554          * related callback was received before the response to the original
555          * call.
556          */
557         if (referring_call_exists(clp, args->csa_nrclists, args->csa_rclists,
558                                 &tbl->slot_tbl_lock) < 0) {
559                 status = htonl(NFS4ERR_DELAY);
560                 goto out_unlock;
561         }
562
563         /*
564          * RFC5661 20.9.3
565          * If CB_SEQUENCE returns an error, then the state of the slot
566          * (sequence ID, cached reply) MUST NOT change.
567          */
568         slot->seq_nr = args->csa_sequenceid;
569 out_unlock:
570         spin_unlock(&tbl->slot_tbl_lock);
571
572 out:
573         cps->clp = clp; /* put in nfs4_callback_compound */
574         for (i = 0; i < args->csa_nrclists; i++)
575                 kfree(args->csa_rclists[i].rcl_refcalls);
576         kfree(args->csa_rclists);
577
578         if (status == htonl(NFS4ERR_RETRY_UNCACHED_REP)) {
579                 cps->drc_status = status;
580                 status = 0;
581         } else
582                 res->csr_status = status;
583
584         trace_nfs4_cb_sequence(args, res, status);
585         return status;
586 }
587
588 static bool
589 validate_bitmap_values(unsigned int mask)
590 {
591         return (mask & ~RCA4_TYPE_MASK_ALL) == 0;
592 }
593
594 __be32 nfs4_callback_recallany(void *argp, void *resp,
595                                struct cb_process_state *cps)
596 {
597         struct cb_recallanyargs *args = argp;
598         __be32 status;
599         fmode_t flags = 0;
600         bool schedule_manager = false;
601
602         status = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION);
603         if (!cps->clp) /* set in cb_sequence */
604                 goto out;
605
606         dprintk_rcu("NFS: RECALL_ANY callback request from %s\n",
607                 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
608
609         status = cpu_to_be32(NFS4ERR_INVAL);
610         if (!validate_bitmap_values(args->craa_type_mask))
611                 goto out;
612
613         status = cpu_to_be32(NFS4_OK);
614         if (args->craa_type_mask & BIT(RCA4_TYPE_MASK_RDATA_DLG))
615                 flags = FMODE_READ;
616         if (args->craa_type_mask & BIT(RCA4_TYPE_MASK_WDATA_DLG))
617                 flags |= FMODE_WRITE;
618         if (flags)
619                 nfs_expire_unused_delegation_types(cps->clp, flags);
620
621         if (args->craa_type_mask & BIT(RCA4_TYPE_MASK_FILE_LAYOUT))
622                 pnfs_recall_all_layouts(cps->clp);
623
624         if (args->craa_type_mask & BIT(PNFS_FF_RCA4_TYPE_MASK_READ)) {
625                 set_bit(NFS4CLNT_RECALL_ANY_LAYOUT_READ, &cps->clp->cl_state);
626                 schedule_manager = true;
627         }
628         if (args->craa_type_mask & BIT(PNFS_FF_RCA4_TYPE_MASK_RW)) {
629                 set_bit(NFS4CLNT_RECALL_ANY_LAYOUT_RW, &cps->clp->cl_state);
630                 schedule_manager = true;
631         }
632         if (schedule_manager)
633                 nfs4_schedule_state_manager(cps->clp);
634
635 out:
636         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
637         return status;
638 }
639
640 /* Reduce the fore channel's max_slots to the target value */
641 __be32 nfs4_callback_recallslot(void *argp, void *resp,
642                                 struct cb_process_state *cps)
643 {
644         struct cb_recallslotargs *args = argp;
645         struct nfs4_slot_table *fc_tbl;
646         __be32 status;
647
648         status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
649         if (!cps->clp) /* set in cb_sequence */
650                 goto out;
651
652         dprintk_rcu("NFS: CB_RECALL_SLOT request from %s target highest slotid %u\n",
653                 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR),
654                 args->crsa_target_highest_slotid);
655
656         fc_tbl = &cps->clp->cl_session->fc_slot_table;
657
658         status = htonl(NFS4_OK);
659
660         nfs41_set_target_slotid(fc_tbl, args->crsa_target_highest_slotid);
661         nfs41_notify_server(cps->clp);
662 out:
663         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
664         return status;
665 }
666
667 __be32 nfs4_callback_notify_lock(void *argp, void *resp,
668                                  struct cb_process_state *cps)
669 {
670         struct cb_notify_lock_args *args = argp;
671
672         if (!cps->clp) /* set in cb_sequence */
673                 return htonl(NFS4ERR_OP_NOT_IN_SESSION);
674
675         dprintk_rcu("NFS: CB_NOTIFY_LOCK request from %s\n",
676                 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
677
678         /* Don't wake anybody if the string looked bogus */
679         if (args->cbnl_valid)
680                 __wake_up(&cps->clp->cl_lock_waitq, TASK_NORMAL, 0, args);
681
682         return htonl(NFS4_OK);
683 }
684 #endif /* CONFIG_NFS_V4_1 */
685 #ifdef CONFIG_NFS_V4_2
686 static void nfs4_copy_cb_args(struct nfs4_copy_state *cp_state,
687                                 struct cb_offloadargs *args)
688 {
689         cp_state->count = args->wr_count;
690         cp_state->error = args->error;
691         if (!args->error) {
692                 cp_state->verf.committed = args->wr_writeverf.committed;
693                 memcpy(&cp_state->verf.verifier.data[0],
694                         &args->wr_writeverf.verifier.data[0],
695                         NFS4_VERIFIER_SIZE);
696         }
697 }
698
699 __be32 nfs4_callback_offload(void *data, void *dummy,
700                              struct cb_process_state *cps)
701 {
702         struct cb_offloadargs *args = data;
703         struct nfs_server *server;
704         struct nfs4_copy_state *copy, *tmp_copy;
705         bool found = false;
706
707         copy = kzalloc(sizeof(struct nfs4_copy_state), GFP_NOFS);
708         if (!copy)
709                 return htonl(NFS4ERR_SERVERFAULT);
710
711         spin_lock(&cps->clp->cl_lock);
712         rcu_read_lock();
713         list_for_each_entry_rcu(server, &cps->clp->cl_superblocks,
714                                 client_link) {
715                 list_for_each_entry(tmp_copy, &server->ss_copies, copies) {
716                         if (memcmp(args->coa_stateid.other,
717                                         tmp_copy->stateid.other,
718                                         sizeof(args->coa_stateid.other)))
719                                 continue;
720                         nfs4_copy_cb_args(tmp_copy, args);
721                         complete(&tmp_copy->completion);
722                         found = true;
723                         goto out;
724                 }
725         }
726 out:
727         rcu_read_unlock();
728         if (!found) {
729                 memcpy(&copy->stateid, &args->coa_stateid, NFS4_STATEID_SIZE);
730                 nfs4_copy_cb_args(copy, args);
731                 list_add_tail(&copy->copies, &cps->clp->pending_cb_stateids);
732         } else
733                 kfree(copy);
734         spin_unlock(&cps->clp->cl_lock);
735
736         return 0;
737 }
738 #endif /* CONFIG_NFS_V4_2 */