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 request
 378  *                                 for @page
 379  * @cinfo - commit info for current inode
 380  * @page - page to search for matching head request
 381  *
 382  * Return: the head request if one is found, otherwise %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_storage *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                                 &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                                                 &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