kdbus: export needed symbols for out-of-tree support
[platform/kernel/linux-rpi.git] / fs / nfs / pnfs_nfs.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Common NFS I/O  operations for the pnfs file based
4  * layout drivers.
5  *
6  * Copyright (c) 2014, Primary Data, Inc. All rights reserved.
7  *
8  * Tom Haynes <loghyr@primarydata.com>
9  */
10
11 #include <linux/nfs_fs.h>
12 #include <linux/nfs_page.h>
13 #include <linux/sunrpc/addr.h>
14 #include <linux/module.h>
15
16 #include "nfs4session.h"
17 #include "internal.h"
18 #include "pnfs.h"
19
20 #define NFSDBG_FACILITY         NFSDBG_PNFS
21
22 void pnfs_generic_rw_release(void *data)
23 {
24         struct nfs_pgio_header *hdr = data;
25
26         nfs_put_client(hdr->ds_clp);
27         hdr->mds_ops->rpc_release(data);
28 }
29 EXPORT_SYMBOL_GPL(pnfs_generic_rw_release);
30
31 /* Fake up some data that will cause nfs_commit_release to retry the writes. */
32 void pnfs_generic_prepare_to_resend_writes(struct nfs_commit_data *data)
33 {
34         struct nfs_writeverf *verf = data->res.verf;
35
36         data->task.tk_status = 0;
37         memset(&verf->verifier, 0, sizeof(verf->verifier));
38         verf->committed = NFS_UNSTABLE;
39 }
40 EXPORT_SYMBOL_GPL(pnfs_generic_prepare_to_resend_writes);
41
42 void pnfs_generic_write_commit_done(struct rpc_task *task, void *data)
43 {
44         struct nfs_commit_data *wdata = data;
45
46         /* Note this may cause RPC to be resent */
47         wdata->mds_ops->rpc_call_done(task, data);
48 }
49 EXPORT_SYMBOL_GPL(pnfs_generic_write_commit_done);
50
51 void pnfs_generic_commit_release(void *calldata)
52 {
53         struct nfs_commit_data *data = calldata;
54
55         data->completion_ops->completion(data);
56         pnfs_put_lseg(data->lseg);
57         nfs_put_client(data->ds_clp);
58         nfs_commitdata_release(data);
59 }
60 EXPORT_SYMBOL_GPL(pnfs_generic_commit_release);
61
62 static struct pnfs_layout_segment *
63 pnfs_free_bucket_lseg(struct pnfs_commit_bucket *bucket)
64 {
65         if (list_empty(&bucket->committing) && list_empty(&bucket->written)) {
66                 struct pnfs_layout_segment *freeme = bucket->lseg;
67                 bucket->lseg = NULL;
68                 return freeme;
69         }
70         return NULL;
71 }
72
73 /* The generic layer is about to remove the req from the commit list.
74  * If this will make the bucket empty, it will need to put the lseg reference.
75  * Note this must be called holding nfsi->commit_mutex
76  */
77 void
78 pnfs_generic_clear_request_commit(struct nfs_page *req,
79                                   struct nfs_commit_info *cinfo)
80 {
81         struct pnfs_commit_bucket *bucket = NULL;
82
83         if (!test_and_clear_bit(PG_COMMIT_TO_DS, &req->wb_flags))
84                 goto out;
85         cinfo->ds->nwritten--;
86         if (list_is_singular(&req->wb_list))
87                 bucket = list_first_entry(&req->wb_list,
88                                           struct pnfs_commit_bucket, written);
89 out:
90         nfs_request_remove_commit_list(req, cinfo);
91         if (bucket)
92                 pnfs_put_lseg(pnfs_free_bucket_lseg(bucket));
93 }
94 EXPORT_SYMBOL_GPL(pnfs_generic_clear_request_commit);
95
96 struct pnfs_commit_array *
97 pnfs_alloc_commit_array(size_t n, gfp_t gfp_flags)
98 {
99         struct pnfs_commit_array *p;
100         struct pnfs_commit_bucket *b;
101
102         p = kmalloc(struct_size(p, buckets, n), gfp_flags);
103         if (!p)
104                 return NULL;
105         p->nbuckets = n;
106         INIT_LIST_HEAD(&p->cinfo_list);
107         INIT_LIST_HEAD(&p->lseg_list);
108         p->lseg = NULL;
109         for (b = &p->buckets[0]; n != 0; b++, n--) {
110                 INIT_LIST_HEAD(&b->written);
111                 INIT_LIST_HEAD(&b->committing);
112                 b->lseg = NULL;
113                 b->direct_verf.committed = NFS_INVALID_STABLE_HOW;
114         }
115         return p;
116 }
117 EXPORT_SYMBOL_GPL(pnfs_alloc_commit_array);
118
119 void
120 pnfs_free_commit_array(struct pnfs_commit_array *p)
121 {
122         kfree_rcu(p, rcu);
123 }
124 EXPORT_SYMBOL_GPL(pnfs_free_commit_array);
125
126 static struct pnfs_commit_array *
127 pnfs_find_commit_array_by_lseg(struct pnfs_ds_commit_info *fl_cinfo,
128                 struct pnfs_layout_segment *lseg)
129 {
130         struct pnfs_commit_array *array;
131
132         list_for_each_entry_rcu(array, &fl_cinfo->commits, cinfo_list) {
133                 if (array->lseg == lseg)
134                         return array;
135         }
136         return NULL;
137 }
138
139 struct pnfs_commit_array *
140 pnfs_add_commit_array(struct pnfs_ds_commit_info *fl_cinfo,
141                 struct pnfs_commit_array *new,
142                 struct pnfs_layout_segment *lseg)
143 {
144         struct pnfs_commit_array *array;
145
146         array = pnfs_find_commit_array_by_lseg(fl_cinfo, lseg);
147         if (array)
148                 return array;
149         new->lseg = lseg;
150         refcount_set(&new->refcount, 1);
151         list_add_rcu(&new->cinfo_list, &fl_cinfo->commits);
152         list_add(&new->lseg_list, &lseg->pls_commits);
153         return new;
154 }
155 EXPORT_SYMBOL_GPL(pnfs_add_commit_array);
156
157 static struct pnfs_commit_array *
158 pnfs_lookup_commit_array(struct pnfs_ds_commit_info *fl_cinfo,
159                 struct pnfs_layout_segment *lseg)
160 {
161         struct pnfs_commit_array *array;
162
163         rcu_read_lock();
164         array = pnfs_find_commit_array_by_lseg(fl_cinfo, lseg);
165         if (!array) {
166                 rcu_read_unlock();
167                 fl_cinfo->ops->setup_ds_info(fl_cinfo, lseg);
168                 rcu_read_lock();
169                 array = pnfs_find_commit_array_by_lseg(fl_cinfo, lseg);
170         }
171         rcu_read_unlock();
172         return array;
173 }
174
175 static void
176 pnfs_release_commit_array_locked(struct pnfs_commit_array *array)
177 {
178         list_del_rcu(&array->cinfo_list);
179         list_del(&array->lseg_list);
180         pnfs_free_commit_array(array);
181 }
182
183 static void
184 pnfs_put_commit_array_locked(struct pnfs_commit_array *array)
185 {
186         if (refcount_dec_and_test(&array->refcount))
187                 pnfs_release_commit_array_locked(array);
188 }
189
190 static void
191 pnfs_put_commit_array(struct pnfs_commit_array *array, struct inode *inode)
192 {
193         if (refcount_dec_and_lock(&array->refcount, &inode->i_lock)) {
194                 pnfs_release_commit_array_locked(array);
195                 spin_unlock(&inode->i_lock);
196         }
197 }
198
199 static struct pnfs_commit_array *
200 pnfs_get_commit_array(struct pnfs_commit_array *array)
201 {
202         if (refcount_inc_not_zero(&array->refcount))
203                 return array;
204         return NULL;
205 }
206
207 static void
208 pnfs_remove_and_free_commit_array(struct pnfs_commit_array *array)
209 {
210         array->lseg = NULL;
211         list_del_init(&array->lseg_list);
212         pnfs_put_commit_array_locked(array);
213 }
214
215 void
216 pnfs_generic_ds_cinfo_release_lseg(struct pnfs_ds_commit_info *fl_cinfo,
217                 struct pnfs_layout_segment *lseg)
218 {
219         struct pnfs_commit_array *array, *tmp;
220
221         list_for_each_entry_safe(array, tmp, &lseg->pls_commits, lseg_list)
222                 pnfs_remove_and_free_commit_array(array);
223 }
224 EXPORT_SYMBOL_GPL(pnfs_generic_ds_cinfo_release_lseg);
225
226 void
227 pnfs_generic_ds_cinfo_destroy(struct pnfs_ds_commit_info *fl_cinfo)
228 {
229         struct pnfs_commit_array *array, *tmp;
230
231         list_for_each_entry_safe(array, tmp, &fl_cinfo->commits, cinfo_list)
232                 pnfs_remove_and_free_commit_array(array);
233 }
234 EXPORT_SYMBOL_GPL(pnfs_generic_ds_cinfo_destroy);
235
236 /*
237  * Locks the nfs_page requests for commit and moves them to
238  * @bucket->committing.
239  */
240 static int
241 pnfs_bucket_scan_ds_commit_list(struct pnfs_commit_bucket *bucket,
242                                 struct nfs_commit_info *cinfo,
243                                 int max)
244 {
245         struct list_head *src = &bucket->written;
246         struct list_head *dst = &bucket->committing;
247         int ret;
248
249         lockdep_assert_held(&NFS_I(cinfo->inode)->commit_mutex);
250         ret = nfs_scan_commit_list(src, dst, cinfo, max);
251         if (ret) {
252                 cinfo->ds->nwritten -= ret;
253                 cinfo->ds->ncommitting += ret;
254         }
255         return ret;
256 }
257
258 static int pnfs_bucket_scan_array(struct nfs_commit_info *cinfo,
259                                   struct pnfs_commit_bucket *buckets,
260                                   unsigned int nbuckets,
261                                   int max)
262 {
263         unsigned int i;
264         int rv = 0, cnt;
265
266         for (i = 0; i < nbuckets && max != 0; i++) {
267                 cnt = pnfs_bucket_scan_ds_commit_list(&buckets[i], cinfo, max);
268                 rv += cnt;
269                 max -= cnt;
270         }
271         return rv;
272 }
273
274 /* Move reqs from written to committing lists, returning count
275  * of number moved.
276  */
277 int pnfs_generic_scan_commit_lists(struct nfs_commit_info *cinfo, int max)
278 {
279         struct pnfs_ds_commit_info *fl_cinfo = cinfo->ds;
280         struct pnfs_commit_array *array;
281         int rv = 0, cnt;
282
283         rcu_read_lock();
284         list_for_each_entry_rcu(array, &fl_cinfo->commits, cinfo_list) {
285                 if (!array->lseg || !pnfs_get_commit_array(array))
286                         continue;
287                 rcu_read_unlock();
288                 cnt = pnfs_bucket_scan_array(cinfo, array->buckets,
289                                 array->nbuckets, max);
290                 rcu_read_lock();
291                 pnfs_put_commit_array(array, cinfo->inode);
292                 rv += cnt;
293                 max -= cnt;
294                 if (!max)
295                         break;
296         }
297         rcu_read_unlock();
298         return rv;
299 }
300 EXPORT_SYMBOL_GPL(pnfs_generic_scan_commit_lists);
301
302 static unsigned int
303 pnfs_bucket_recover_commit_reqs(struct list_head *dst,
304                                 struct pnfs_commit_bucket *buckets,
305                                 unsigned int nbuckets,
306                                 struct nfs_commit_info *cinfo)
307 {
308         struct pnfs_commit_bucket *b;
309         struct pnfs_layout_segment *freeme;
310         unsigned int nwritten, ret = 0;
311         unsigned int i;
312
313 restart:
314         for (i = 0, b = buckets; i < nbuckets; i++, b++) {
315                 nwritten = nfs_scan_commit_list(&b->written, dst, cinfo, 0);
316                 if (!nwritten)
317                         continue;
318                 ret += nwritten;
319                 freeme = pnfs_free_bucket_lseg(b);
320                 if (freeme) {
321                         pnfs_put_lseg(freeme);
322                         goto restart;
323                 }
324         }
325         return ret;
326 }
327
328 /* Pull everything off the committing lists and dump into @dst.  */
329 void pnfs_generic_recover_commit_reqs(struct list_head *dst,
330                                       struct nfs_commit_info *cinfo)
331 {
332         struct pnfs_ds_commit_info *fl_cinfo = cinfo->ds;
333         struct pnfs_commit_array *array;
334         unsigned int nwritten;
335
336         lockdep_assert_held(&NFS_I(cinfo->inode)->commit_mutex);
337         rcu_read_lock();
338         list_for_each_entry_rcu(array, &fl_cinfo->commits, cinfo_list) {
339                 if (!array->lseg || !pnfs_get_commit_array(array))
340                         continue;
341                 rcu_read_unlock();
342                 nwritten = pnfs_bucket_recover_commit_reqs(dst,
343                                                            array->buckets,
344                                                            array->nbuckets,
345                                                            cinfo);
346                 rcu_read_lock();
347                 pnfs_put_commit_array(array, cinfo->inode);
348                 fl_cinfo->nwritten -= nwritten;
349         }
350         rcu_read_unlock();
351 }
352 EXPORT_SYMBOL_GPL(pnfs_generic_recover_commit_reqs);
353
354 static struct nfs_page *
355 pnfs_bucket_search_commit_reqs(struct pnfs_commit_bucket *buckets,
356                 unsigned int nbuckets, struct page *page)
357 {
358         struct nfs_page *req;
359         struct pnfs_commit_bucket *b;
360         unsigned int i;
361
362         /* Linearly search the commit lists for each bucket until a matching
363          * request is found */
364         for (i = 0, b = buckets; i < nbuckets; i++, b++) {
365                 list_for_each_entry(req, &b->written, wb_list) {
366                         if (req->wb_page == page)
367                                 return req->wb_head;
368                 }
369                 list_for_each_entry(req, &b->committing, wb_list) {
370                         if (req->wb_page == page)
371                                 return req->wb_head;
372                 }
373         }
374         return NULL;
375 }
376
377 /* pnfs_generic_search_commit_reqs - Search lists in @cinfo for the head reqest
378  *                                 for @page
379  * @cinfo - commit info for current inode
380  * @page - page to search for matching head request
381  *
382  * Returns a the head request if one is found, otherwise returns NULL.
383  */
384 struct nfs_page *
385 pnfs_generic_search_commit_reqs(struct nfs_commit_info *cinfo, struct page *page)
386 {
387         struct pnfs_ds_commit_info *fl_cinfo = cinfo->ds;
388         struct pnfs_commit_array *array;
389         struct nfs_page *req;
390
391         list_for_each_entry(array, &fl_cinfo->commits, cinfo_list) {
392                 req = pnfs_bucket_search_commit_reqs(array->buckets,
393                                 array->nbuckets, page);
394                 if (req)
395                         return req;
396         }
397         return NULL;
398 }
399 EXPORT_SYMBOL_GPL(pnfs_generic_search_commit_reqs);
400
401 static struct pnfs_layout_segment *
402 pnfs_bucket_get_committing(struct list_head *head,
403                            struct pnfs_commit_bucket *bucket,
404                            struct nfs_commit_info *cinfo)
405 {
406         struct pnfs_layout_segment *lseg;
407         struct list_head *pos;
408
409         list_for_each(pos, &bucket->committing)
410                 cinfo->ds->ncommitting--;
411         list_splice_init(&bucket->committing, head);
412         lseg = pnfs_free_bucket_lseg(bucket);
413         if (!lseg)
414                 lseg = pnfs_get_lseg(bucket->lseg);
415         return lseg;
416 }
417
418 static struct nfs_commit_data *
419 pnfs_bucket_fetch_commitdata(struct pnfs_commit_bucket *bucket,
420                              struct nfs_commit_info *cinfo)
421 {
422         struct nfs_commit_data *data = nfs_commitdata_alloc();
423
424         if (!data)
425                 return NULL;
426         data->lseg = pnfs_bucket_get_committing(&data->pages, bucket, cinfo);
427         return data;
428 }
429
430 static void pnfs_generic_retry_commit(struct pnfs_commit_bucket *buckets,
431                                       unsigned int nbuckets,
432                                       struct nfs_commit_info *cinfo,
433                                       unsigned int idx)
434 {
435         struct pnfs_commit_bucket *bucket;
436         struct pnfs_layout_segment *freeme;
437         LIST_HEAD(pages);
438
439         for (bucket = buckets; idx < nbuckets; bucket++, idx++) {
440                 if (list_empty(&bucket->committing))
441                         continue;
442                 mutex_lock(&NFS_I(cinfo->inode)->commit_mutex);
443                 freeme = pnfs_bucket_get_committing(&pages, bucket, cinfo);
444                 mutex_unlock(&NFS_I(cinfo->inode)->commit_mutex);
445                 nfs_retry_commit(&pages, freeme, cinfo, idx);
446                 pnfs_put_lseg(freeme);
447         }
448 }
449
450 static unsigned int
451 pnfs_bucket_alloc_ds_commits(struct list_head *list,
452                              struct pnfs_commit_bucket *buckets,
453                              unsigned int nbuckets,
454                              struct nfs_commit_info *cinfo)
455 {
456         struct pnfs_commit_bucket *bucket;
457         struct nfs_commit_data *data;
458         unsigned int i;
459         unsigned int nreq = 0;
460
461         for (i = 0, bucket = buckets; i < nbuckets; i++, bucket++) {
462                 if (list_empty(&bucket->committing))
463                         continue;
464                 mutex_lock(&NFS_I(cinfo->inode)->commit_mutex);
465                 if (!list_empty(&bucket->committing)) {
466                         data = pnfs_bucket_fetch_commitdata(bucket, cinfo);
467                         if (!data)
468                                 goto out_error;
469                         data->ds_commit_index = i;
470                         list_add_tail(&data->list, list);
471                         nreq++;
472                 }
473                 mutex_unlock(&NFS_I(cinfo->inode)->commit_mutex);
474         }
475         return nreq;
476 out_error:
477         mutex_unlock(&NFS_I(cinfo->inode)->commit_mutex);
478         /* Clean up on error */
479         pnfs_generic_retry_commit(buckets, nbuckets, cinfo, i);
480         return nreq;
481 }
482
483 static unsigned int
484 pnfs_alloc_ds_commits_list(struct list_head *list,
485                            struct pnfs_ds_commit_info *fl_cinfo,
486                            struct nfs_commit_info *cinfo)
487 {
488         struct pnfs_commit_array *array;
489         unsigned int ret = 0;
490
491         rcu_read_lock();
492         list_for_each_entry_rcu(array, &fl_cinfo->commits, cinfo_list) {
493                 if (!array->lseg || !pnfs_get_commit_array(array))
494                         continue;
495                 rcu_read_unlock();
496                 ret += pnfs_bucket_alloc_ds_commits(list, array->buckets,
497                                 array->nbuckets, cinfo);
498                 rcu_read_lock();
499                 pnfs_put_commit_array(array, cinfo->inode);
500         }
501         rcu_read_unlock();
502         return ret;
503 }
504
505 /* This follows nfs_commit_list pretty closely */
506 int
507 pnfs_generic_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
508                              int how, struct nfs_commit_info *cinfo,
509                              int (*initiate_commit)(struct nfs_commit_data *data,
510                                                     int how))
511 {
512         struct pnfs_ds_commit_info *fl_cinfo = cinfo->ds;
513         struct nfs_commit_data *data, *tmp;
514         LIST_HEAD(list);
515         unsigned int nreq = 0;
516
517         if (!list_empty(mds_pages)) {
518                 data = nfs_commitdata_alloc();
519                 if (!data) {
520                         nfs_retry_commit(mds_pages, NULL, cinfo, -1);
521                         return -ENOMEM;
522                 }
523                 data->ds_commit_index = -1;
524                 list_splice_init(mds_pages, &data->pages);
525                 list_add_tail(&data->list, &list);
526                 nreq++;
527         }
528
529         nreq += pnfs_alloc_ds_commits_list(&list, fl_cinfo, cinfo);
530         if (nreq == 0)
531                 goto out;
532
533         list_for_each_entry_safe(data, tmp, &list, list) {
534                 list_del(&data->list);
535                 if (data->ds_commit_index < 0) {
536                         nfs_init_commit(data, NULL, NULL, cinfo);
537                         nfs_initiate_commit(NFS_CLIENT(inode), data,
538                                             NFS_PROTO(data->inode),
539                                             data->mds_ops, how,
540                                             RPC_TASK_CRED_NOREF);
541                 } else {
542                         nfs_init_commit(data, NULL, data->lseg, cinfo);
543                         initiate_commit(data, how);
544                 }
545         }
546 out:
547         return PNFS_ATTEMPTED;
548 }
549 EXPORT_SYMBOL_GPL(pnfs_generic_commit_pagelist);
550
551 /*
552  * Data server cache
553  *
554  * Data servers can be mapped to different device ids.
555  * nfs4_pnfs_ds reference counting
556  *   - set to 1 on allocation
557  *   - incremented when a device id maps a data server already in the cache.
558  *   - decremented when deviceid is removed from the cache.
559  */
560 static DEFINE_SPINLOCK(nfs4_ds_cache_lock);
561 static LIST_HEAD(nfs4_data_server_cache);
562
563 /* Debug routines */
564 static void
565 print_ds(struct nfs4_pnfs_ds *ds)
566 {
567         if (ds == NULL) {
568                 printk(KERN_WARNING "%s NULL device\n", __func__);
569                 return;
570         }
571         printk(KERN_WARNING "        ds %s\n"
572                 "        ref count %d\n"
573                 "        client %p\n"
574                 "        cl_exchange_flags %x\n",
575                 ds->ds_remotestr,
576                 refcount_read(&ds->ds_count), ds->ds_clp,
577                 ds->ds_clp ? ds->ds_clp->cl_exchange_flags : 0);
578 }
579
580 static bool
581 same_sockaddr(struct sockaddr *addr1, struct sockaddr *addr2)
582 {
583         struct sockaddr_in *a, *b;
584         struct sockaddr_in6 *a6, *b6;
585
586         if (addr1->sa_family != addr2->sa_family)
587                 return false;
588
589         switch (addr1->sa_family) {
590         case AF_INET:
591                 a = (struct sockaddr_in *)addr1;
592                 b = (struct sockaddr_in *)addr2;
593
594                 if (a->sin_addr.s_addr == b->sin_addr.s_addr &&
595                     a->sin_port == b->sin_port)
596                         return true;
597                 break;
598
599         case AF_INET6:
600                 a6 = (struct sockaddr_in6 *)addr1;
601                 b6 = (struct sockaddr_in6 *)addr2;
602
603                 /* LINKLOCAL addresses must have matching scope_id */
604                 if (ipv6_addr_src_scope(&a6->sin6_addr) ==
605                     IPV6_ADDR_SCOPE_LINKLOCAL &&
606                     a6->sin6_scope_id != b6->sin6_scope_id)
607                         return false;
608
609                 if (ipv6_addr_equal(&a6->sin6_addr, &b6->sin6_addr) &&
610                     a6->sin6_port == b6->sin6_port)
611                         return true;
612                 break;
613
614         default:
615                 dprintk("%s: unhandled address family: %u\n",
616                         __func__, addr1->sa_family);
617                 return false;
618         }
619
620         return false;
621 }
622
623 /*
624  * Checks if 'dsaddrs1' contains a subset of 'dsaddrs2'. If it does,
625  * declare a match.
626  */
627 static bool
628 _same_data_server_addrs_locked(const struct list_head *dsaddrs1,
629                                const struct list_head *dsaddrs2)
630 {
631         struct nfs4_pnfs_ds_addr *da1, *da2;
632         struct sockaddr *sa1, *sa2;
633         bool match = false;
634
635         list_for_each_entry(da1, dsaddrs1, da_node) {
636                 sa1 = (struct sockaddr *)&da1->da_addr;
637                 match = false;
638                 list_for_each_entry(da2, dsaddrs2, da_node) {
639                         sa2 = (struct sockaddr *)&da2->da_addr;
640                         match = same_sockaddr(sa1, sa2);
641                         if (match)
642                                 break;
643                 }
644                 if (!match)
645                         break;
646         }
647         return match;
648 }
649
650 /*
651  * Lookup DS by addresses.  nfs4_ds_cache_lock is held
652  */
653 static struct nfs4_pnfs_ds *
654 _data_server_lookup_locked(const struct list_head *dsaddrs)
655 {
656         struct nfs4_pnfs_ds *ds;
657
658         list_for_each_entry(ds, &nfs4_data_server_cache, ds_node)
659                 if (_same_data_server_addrs_locked(&ds->ds_addrs, dsaddrs))
660                         return ds;
661         return NULL;
662 }
663
664 static struct nfs4_pnfs_ds_addr *nfs4_pnfs_ds_addr_alloc(gfp_t gfp_flags)
665 {
666         struct nfs4_pnfs_ds_addr *da = kzalloc(sizeof(*da), gfp_flags);
667         if (da)
668                 INIT_LIST_HEAD(&da->da_node);
669         return da;
670 }
671
672 static void nfs4_pnfs_ds_addr_free(struct nfs4_pnfs_ds_addr *da)
673 {
674         kfree(da->da_remotestr);
675         kfree(da->da_netid);
676         kfree(da);
677 }
678
679 static void destroy_ds(struct nfs4_pnfs_ds *ds)
680 {
681         struct nfs4_pnfs_ds_addr *da;
682
683         dprintk("--> %s\n", __func__);
684         ifdebug(FACILITY)
685                 print_ds(ds);
686
687         nfs_put_client(ds->ds_clp);
688
689         while (!list_empty(&ds->ds_addrs)) {
690                 da = list_first_entry(&ds->ds_addrs,
691                                       struct nfs4_pnfs_ds_addr,
692                                       da_node);
693                 list_del_init(&da->da_node);
694                 nfs4_pnfs_ds_addr_free(da);
695         }
696
697         kfree(ds->ds_remotestr);
698         kfree(ds);
699 }
700
701 void nfs4_pnfs_ds_put(struct nfs4_pnfs_ds *ds)
702 {
703         if (refcount_dec_and_lock(&ds->ds_count,
704                                 &nfs4_ds_cache_lock)) {
705                 list_del_init(&ds->ds_node);
706                 spin_unlock(&nfs4_ds_cache_lock);
707                 destroy_ds(ds);
708         }
709 }
710 EXPORT_SYMBOL_GPL(nfs4_pnfs_ds_put);
711
712 /*
713  * Create a string with a human readable address and port to avoid
714  * complicated setup around many dprinks.
715  */
716 static char *
717 nfs4_pnfs_remotestr(struct list_head *dsaddrs, gfp_t gfp_flags)
718 {
719         struct nfs4_pnfs_ds_addr *da;
720         char *remotestr;
721         size_t len;
722         char *p;
723
724         len = 3;        /* '{', '}' and eol */
725         list_for_each_entry(da, dsaddrs, da_node) {
726                 len += strlen(da->da_remotestr) + 1;    /* string plus comma */
727         }
728
729         remotestr = kzalloc(len, gfp_flags);
730         if (!remotestr)
731                 return NULL;
732
733         p = remotestr;
734         *(p++) = '{';
735         len--;
736         list_for_each_entry(da, dsaddrs, da_node) {
737                 size_t ll = strlen(da->da_remotestr);
738
739                 if (ll > len)
740                         goto out_err;
741
742                 memcpy(p, da->da_remotestr, ll);
743                 p += ll;
744                 len -= ll;
745
746                 if (len < 1)
747                         goto out_err;
748                 (*p++) = ',';
749                 len--;
750         }
751         if (len < 2)
752                 goto out_err;
753         *(p++) = '}';
754         *p = '\0';
755         return remotestr;
756 out_err:
757         kfree(remotestr);
758         return NULL;
759 }
760
761 /*
762  * Given a list of multipath struct nfs4_pnfs_ds_addr, add it to ds cache if
763  * uncached and return cached struct nfs4_pnfs_ds.
764  */
765 struct nfs4_pnfs_ds *
766 nfs4_pnfs_ds_add(struct list_head *dsaddrs, gfp_t gfp_flags)
767 {
768         struct nfs4_pnfs_ds *tmp_ds, *ds = NULL;
769         char *remotestr;
770
771         if (list_empty(dsaddrs)) {
772                 dprintk("%s: no addresses defined\n", __func__);
773                 goto out;
774         }
775
776         ds = kzalloc(sizeof(*ds), gfp_flags);
777         if (!ds)
778                 goto out;
779
780         /* this is only used for debugging, so it's ok if its NULL */
781         remotestr = nfs4_pnfs_remotestr(dsaddrs, gfp_flags);
782
783         spin_lock(&nfs4_ds_cache_lock);
784         tmp_ds = _data_server_lookup_locked(dsaddrs);
785         if (tmp_ds == NULL) {
786                 INIT_LIST_HEAD(&ds->ds_addrs);
787                 list_splice_init(dsaddrs, &ds->ds_addrs);
788                 ds->ds_remotestr = remotestr;
789                 refcount_set(&ds->ds_count, 1);
790                 INIT_LIST_HEAD(&ds->ds_node);
791                 ds->ds_clp = NULL;
792                 list_add(&ds->ds_node, &nfs4_data_server_cache);
793                 dprintk("%s add new data server %s\n", __func__,
794                         ds->ds_remotestr);
795         } else {
796                 kfree(remotestr);
797                 kfree(ds);
798                 refcount_inc(&tmp_ds->ds_count);
799                 dprintk("%s data server %s found, inc'ed ds_count to %d\n",
800                         __func__, tmp_ds->ds_remotestr,
801                         refcount_read(&tmp_ds->ds_count));
802                 ds = tmp_ds;
803         }
804         spin_unlock(&nfs4_ds_cache_lock);
805 out:
806         return ds;
807 }
808 EXPORT_SYMBOL_GPL(nfs4_pnfs_ds_add);
809
810 static int nfs4_wait_ds_connect(struct nfs4_pnfs_ds *ds)
811 {
812         might_sleep();
813         return wait_on_bit(&ds->ds_state, NFS4DS_CONNECTING, TASK_KILLABLE);
814 }
815
816 static void nfs4_clear_ds_conn_bit(struct nfs4_pnfs_ds *ds)
817 {
818         smp_mb__before_atomic();
819         clear_and_wake_up_bit(NFS4DS_CONNECTING, &ds->ds_state);
820 }
821
822 static struct nfs_client *(*get_v3_ds_connect)(
823                         struct nfs_server *mds_srv,
824                         const struct sockaddr *ds_addr,
825                         int ds_addrlen,
826                         int ds_proto,
827                         unsigned int ds_timeo,
828                         unsigned int ds_retrans);
829
830 static bool load_v3_ds_connect(void)
831 {
832         if (!get_v3_ds_connect) {
833                 get_v3_ds_connect = symbol_request(nfs3_set_ds_client);
834                 WARN_ON_ONCE(!get_v3_ds_connect);
835         }
836
837         return(get_v3_ds_connect != NULL);
838 }
839
840 void nfs4_pnfs_v3_ds_connect_unload(void)
841 {
842         if (get_v3_ds_connect) {
843                 symbol_put(nfs3_set_ds_client);
844                 get_v3_ds_connect = NULL;
845         }
846 }
847
848 static int _nfs4_pnfs_v3_ds_connect(struct nfs_server *mds_srv,
849                                  struct nfs4_pnfs_ds *ds,
850                                  unsigned int timeo,
851                                  unsigned int retrans)
852 {
853         struct nfs_client *clp = ERR_PTR(-EIO);
854         struct nfs4_pnfs_ds_addr *da;
855         int status = 0;
856
857         dprintk("--> %s DS %s\n", __func__, ds->ds_remotestr);
858
859         if (!load_v3_ds_connect())
860                 return -EPROTONOSUPPORT;
861
862         list_for_each_entry(da, &ds->ds_addrs, da_node) {
863                 dprintk("%s: DS %s: trying address %s\n",
864                         __func__, ds->ds_remotestr, da->da_remotestr);
865
866                 if (!IS_ERR(clp)) {
867                         struct xprt_create xprt_args = {
868                                 .ident = da->da_transport,
869                                 .net = clp->cl_net,
870                                 .dstaddr = (struct sockaddr *)&da->da_addr,
871                                 .addrlen = da->da_addrlen,
872                                 .servername = clp->cl_hostname,
873                         };
874
875                         if (da->da_transport != clp->cl_proto)
876                                 continue;
877                         if (da->da_addr.ss_family != clp->cl_addr.ss_family)
878                                 continue;
879                         /* Add this address as an alias */
880                         rpc_clnt_add_xprt(clp->cl_rpcclient, &xprt_args,
881                                         rpc_clnt_test_and_add_xprt, NULL);
882                         continue;
883                 }
884                 clp = get_v3_ds_connect(mds_srv,
885                                 (struct sockaddr *)&da->da_addr,
886                                 da->da_addrlen, da->da_transport,
887                                 timeo, retrans);
888                 if (IS_ERR(clp))
889                         continue;
890                 clp->cl_rpcclient->cl_softerr = 0;
891                 clp->cl_rpcclient->cl_softrtry = 0;
892         }
893
894         if (IS_ERR(clp)) {
895                 status = PTR_ERR(clp);
896                 goto out;
897         }
898
899         smp_wmb();
900         WRITE_ONCE(ds->ds_clp, clp);
901         dprintk("%s [new] addr: %s\n", __func__, ds->ds_remotestr);
902 out:
903         return status;
904 }
905
906 static int _nfs4_pnfs_v4_ds_connect(struct nfs_server *mds_srv,
907                                  struct nfs4_pnfs_ds *ds,
908                                  unsigned int timeo,
909                                  unsigned int retrans,
910                                  u32 minor_version)
911 {
912         struct nfs_client *clp = ERR_PTR(-EIO);
913         struct nfs4_pnfs_ds_addr *da;
914         int status = 0;
915
916         dprintk("--> %s DS %s\n", __func__, ds->ds_remotestr);
917
918         list_for_each_entry(da, &ds->ds_addrs, da_node) {
919                 dprintk("%s: DS %s: trying address %s\n",
920                         __func__, ds->ds_remotestr, da->da_remotestr);
921
922                 if (!IS_ERR(clp) && clp->cl_mvops->session_trunk) {
923                         struct xprt_create xprt_args = {
924                                 .ident = da->da_transport,
925                                 .net = clp->cl_net,
926                                 .dstaddr = (struct sockaddr *)&da->da_addr,
927                                 .addrlen = da->da_addrlen,
928                                 .servername = clp->cl_hostname,
929                         };
930                         struct nfs4_add_xprt_data xprtdata = {
931                                 .clp = clp,
932                         };
933                         struct rpc_add_xprt_test rpcdata = {
934                                 .add_xprt_test = clp->cl_mvops->session_trunk,
935                                 .data = &xprtdata,
936                         };
937
938                         if (da->da_transport != clp->cl_proto)
939                                 continue;
940                         if (da->da_addr.ss_family != clp->cl_addr.ss_family)
941                                 continue;
942                         /**
943                         * Test this address for session trunking and
944                         * add as an alias
945                         */
946                         xprtdata.cred = nfs4_get_clid_cred(clp),
947                         rpc_clnt_add_xprt(clp->cl_rpcclient, &xprt_args,
948                                           rpc_clnt_setup_test_and_add_xprt,
949                                           &rpcdata);
950                         if (xprtdata.cred)
951                                 put_cred(xprtdata.cred);
952                 } else {
953                         clp = nfs4_set_ds_client(mds_srv,
954                                                 (struct sockaddr *)&da->da_addr,
955                                                 da->da_addrlen,
956                                                 da->da_transport, timeo,
957                                                 retrans, minor_version);
958                         if (IS_ERR(clp))
959                                 continue;
960
961                         status = nfs4_init_ds_session(clp,
962                                         mds_srv->nfs_client->cl_lease_time);
963                         if (status) {
964                                 nfs_put_client(clp);
965                                 clp = ERR_PTR(-EIO);
966                                 continue;
967                         }
968
969                 }
970         }
971
972         if (IS_ERR(clp)) {
973                 status = PTR_ERR(clp);
974                 goto out;
975         }
976
977         smp_wmb();
978         WRITE_ONCE(ds->ds_clp, clp);
979         dprintk("%s [new] addr: %s\n", __func__, ds->ds_remotestr);
980 out:
981         return status;
982 }
983
984 /*
985  * Create an rpc connection to the nfs4_pnfs_ds data server.
986  * Currently only supports IPv4 and IPv6 addresses.
987  * If connection fails, make devid unavailable and return a -errno.
988  */
989 int nfs4_pnfs_ds_connect(struct nfs_server *mds_srv, struct nfs4_pnfs_ds *ds,
990                           struct nfs4_deviceid_node *devid, unsigned int timeo,
991                           unsigned int retrans, u32 version, u32 minor_version)
992 {
993         int err;
994
995         do {
996                 err = nfs4_wait_ds_connect(ds);
997                 if (err || ds->ds_clp)
998                         goto out;
999                 if (nfs4_test_deviceid_unavailable(devid))
1000                         return -ENODEV;
1001         } while (test_and_set_bit(NFS4DS_CONNECTING, &ds->ds_state) != 0);
1002
1003         if (ds->ds_clp)
1004                 goto connect_done;
1005
1006         switch (version) {
1007         case 3:
1008                 err = _nfs4_pnfs_v3_ds_connect(mds_srv, ds, timeo, retrans);
1009                 break;
1010         case 4:
1011                 err = _nfs4_pnfs_v4_ds_connect(mds_srv, ds, timeo, retrans,
1012                                                minor_version);
1013                 break;
1014         default:
1015                 dprintk("%s: unsupported DS version %d\n", __func__, version);
1016                 err = -EPROTONOSUPPORT;
1017         }
1018
1019 connect_done:
1020         nfs4_clear_ds_conn_bit(ds);
1021 out:
1022         /*
1023          * At this point the ds->ds_clp should be ready, but it might have
1024          * hit an error.
1025          */
1026         if (!err) {
1027                 if (!ds->ds_clp || !nfs_client_init_is_complete(ds->ds_clp)) {
1028                         WARN_ON_ONCE(ds->ds_clp ||
1029                                 !nfs4_test_deviceid_unavailable(devid));
1030                         return -EINVAL;
1031                 }
1032                 err = nfs_client_init_status(ds->ds_clp);
1033         }
1034
1035         return err;
1036 }
1037 EXPORT_SYMBOL_GPL(nfs4_pnfs_ds_connect);
1038
1039 /*
1040  * Currently only supports ipv4, ipv6 and one multi-path address.
1041  */
1042 struct nfs4_pnfs_ds_addr *
1043 nfs4_decode_mp_ds_addr(struct net *net, struct xdr_stream *xdr, gfp_t gfp_flags)
1044 {
1045         struct nfs4_pnfs_ds_addr *da = NULL;
1046         char *buf, *portstr;
1047         __be16 port;
1048         ssize_t nlen, rlen;
1049         int tmp[2];
1050         char *netid;
1051         size_t len;
1052         char *startsep = "";
1053         char *endsep = "";
1054
1055
1056         /* r_netid */
1057         nlen = xdr_stream_decode_string_dup(xdr, &netid, XDR_MAX_NETOBJ,
1058                                             gfp_flags);
1059         if (unlikely(nlen < 0))
1060                 goto out_err;
1061
1062         /* r_addr: ip/ip6addr with port in dec octets - see RFC 5665 */
1063         /* port is ".ABC.DEF", 8 chars max */
1064         rlen = xdr_stream_decode_string_dup(xdr, &buf, INET6_ADDRSTRLEN +
1065                                             IPV6_SCOPE_ID_LEN + 8, gfp_flags);
1066         if (unlikely(rlen < 0))
1067                 goto out_free_netid;
1068
1069         /* replace port '.' with '-' */
1070         portstr = strrchr(buf, '.');
1071         if (!portstr) {
1072                 dprintk("%s: Failed finding expected dot in port\n",
1073                         __func__);
1074                 goto out_free_buf;
1075         }
1076         *portstr = '-';
1077
1078         /* find '.' between address and port */
1079         portstr = strrchr(buf, '.');
1080         if (!portstr) {
1081                 dprintk("%s: Failed finding expected dot between address and "
1082                         "port\n", __func__);
1083                 goto out_free_buf;
1084         }
1085         *portstr = '\0';
1086
1087         da = nfs4_pnfs_ds_addr_alloc(gfp_flags);
1088         if (unlikely(!da))
1089                 goto out_free_buf;
1090
1091         if (!rpc_pton(net, buf, portstr-buf, (struct sockaddr *)&da->da_addr,
1092                       sizeof(da->da_addr))) {
1093                 dprintk("%s: error parsing address %s\n", __func__, buf);
1094                 goto out_free_da;
1095         }
1096
1097         portstr++;
1098         sscanf(portstr, "%d-%d", &tmp[0], &tmp[1]);
1099         port = htons((tmp[0] << 8) | (tmp[1]));
1100
1101         switch (da->da_addr.ss_family) {
1102         case AF_INET:
1103                 ((struct sockaddr_in *)&da->da_addr)->sin_port = port;
1104                 da->da_addrlen = sizeof(struct sockaddr_in);
1105                 break;
1106
1107         case AF_INET6:
1108                 ((struct sockaddr_in6 *)&da->da_addr)->sin6_port = port;
1109                 da->da_addrlen = sizeof(struct sockaddr_in6);
1110                 startsep = "[";
1111                 endsep = "]";
1112                 break;
1113
1114         default:
1115                 dprintk("%s: unsupported address family: %u\n",
1116                         __func__, da->da_addr.ss_family);
1117                 goto out_free_da;
1118         }
1119
1120         da->da_transport = xprt_find_transport_ident(netid);
1121         if (da->da_transport < 0) {
1122                 dprintk("%s: ERROR: unknown r_netid \"%s\"\n",
1123                         __func__, netid);
1124                 goto out_free_da;
1125         }
1126
1127         da->da_netid = netid;
1128
1129         /* save human readable address */
1130         len = strlen(startsep) + strlen(buf) + strlen(endsep) + 7;
1131         da->da_remotestr = kzalloc(len, gfp_flags);
1132
1133         /* NULL is ok, only used for dprintk */
1134         if (da->da_remotestr)
1135                 snprintf(da->da_remotestr, len, "%s%s%s:%u", startsep,
1136                          buf, endsep, ntohs(port));
1137
1138         dprintk("%s: Parsed DS addr %s\n", __func__, da->da_remotestr);
1139         kfree(buf);
1140         return da;
1141
1142 out_free_da:
1143         kfree(da);
1144 out_free_buf:
1145         dprintk("%s: Error parsing DS addr: %s\n", __func__, buf);
1146         kfree(buf);
1147 out_free_netid:
1148         kfree(netid);
1149 out_err:
1150         return NULL;
1151 }
1152 EXPORT_SYMBOL_GPL(nfs4_decode_mp_ds_addr);
1153
1154 void
1155 pnfs_layout_mark_request_commit(struct nfs_page *req,
1156                                 struct pnfs_layout_segment *lseg,
1157                                 struct nfs_commit_info *cinfo,
1158                                 u32 ds_commit_idx)
1159 {
1160         struct list_head *list;
1161         struct pnfs_commit_array *array;
1162         struct pnfs_commit_bucket *bucket;
1163
1164         mutex_lock(&NFS_I(cinfo->inode)->commit_mutex);
1165         array = pnfs_lookup_commit_array(cinfo->ds, lseg);
1166         if (!array || !pnfs_is_valid_lseg(lseg))
1167                 goto out_resched;
1168         bucket = &array->buckets[ds_commit_idx];
1169         list = &bucket->written;
1170         /* Non-empty buckets hold a reference on the lseg.  That ref
1171          * is normally transferred to the COMMIT call and released
1172          * there.  It could also be released if the last req is pulled
1173          * off due to a rewrite, in which case it will be done in
1174          * pnfs_common_clear_request_commit
1175          */
1176         if (!bucket->lseg)
1177                 bucket->lseg = pnfs_get_lseg(lseg);
1178         set_bit(PG_COMMIT_TO_DS, &req->wb_flags);
1179         cinfo->ds->nwritten++;
1180
1181         nfs_request_add_commit_list_locked(req, list, cinfo);
1182         mutex_unlock(&NFS_I(cinfo->inode)->commit_mutex);
1183         nfs_mark_page_unstable(req->wb_page, cinfo);
1184         return;
1185 out_resched:
1186         mutex_unlock(&NFS_I(cinfo->inode)->commit_mutex);
1187         cinfo->completion_ops->resched_write(cinfo, req);
1188 }
1189 EXPORT_SYMBOL_GPL(pnfs_layout_mark_request_commit);
1190
1191 int
1192 pnfs_nfs_generic_sync(struct inode *inode, bool datasync)
1193 {
1194         int ret;
1195
1196         if (!pnfs_layoutcommit_outstanding(inode))
1197                 return 0;
1198         ret = nfs_commit_inode(inode, FLUSH_SYNC);
1199         if (ret < 0)
1200                 return ret;
1201         if (datasync)
1202                 return 0;
1203         return pnfs_layoutcommit_inode(inode, true);
1204 }
1205 EXPORT_SYMBOL_GPL(pnfs_nfs_generic_sync);
1206