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_layout_segment *freeme = 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                 struct pnfs_commit_bucket *bucket;
  88
  89                 bucket = list_first_entry(&req->wb_list,
  90                                           struct pnfs_commit_bucket,
  91                                           written);
  92                 freeme = pnfs_free_bucket_lseg(bucket);
  93         }
  94 out:
  95         nfs_request_remove_commit_list(req, cinfo);
  96         pnfs_put_lseg(freeme);
  97 }
  98 EXPORT_SYMBOL_GPL(pnfs_generic_clear_request_commit);
  99
 100 struct pnfs_commit_array *
 101 pnfs_alloc_commit_array(size_t n, gfp_t gfp_flags)
 102 {
 103         struct pnfs_commit_array *p;
 104         struct pnfs_commit_bucket *b;
 105
 106         p = kmalloc(struct_size(p, buckets, n), gfp_flags);
 107         if (!p)
 108                 return NULL;
 109         p->nbuckets = n;
 110         INIT_LIST_HEAD(&p->cinfo_list);
 111         INIT_LIST_HEAD(&p->lseg_list);
 112         p->lseg = NULL;
 113         for (b = &p->buckets[0]; n != 0; b++, n--) {
 114                 INIT_LIST_HEAD(&b->written);
 115                 INIT_LIST_HEAD(&b->committing);
 116                 b->lseg = NULL;
 117                 b->direct_verf.committed = NFS_INVALID_STABLE_HOW;
 118         }
 119         return p;
 120 }
 121 EXPORT_SYMBOL_GPL(pnfs_alloc_commit_array);
 122
 123 void
 124 pnfs_free_commit_array(struct pnfs_commit_array *p)
 125 {
 126         kfree_rcu(p, rcu);
 127 }
 128 EXPORT_SYMBOL_GPL(pnfs_free_commit_array);
 129
 130 static struct pnfs_commit_array *
 131 pnfs_find_commit_array_by_lseg(struct pnfs_ds_commit_info *fl_cinfo,
 132                 struct pnfs_layout_segment *lseg)
 133 {
 134         struct pnfs_commit_array *array;
 135
 136         list_for_each_entry_rcu(array, &fl_cinfo->commits, cinfo_list) {
 137                 if (array->lseg == lseg)
 138                         return array;
 139         }
 140         return NULL;
 141 }
 142
 143 struct pnfs_commit_array *
 144 pnfs_add_commit_array(struct pnfs_ds_commit_info *fl_cinfo,
 145                 struct pnfs_commit_array *new,
 146                 struct pnfs_layout_segment *lseg)
 147 {
 148         struct pnfs_commit_array *array;
 149
 150         array = pnfs_find_commit_array_by_lseg(fl_cinfo, lseg);
 151         if (array)
 152                 return array;
 153         new->lseg = lseg;
 154         refcount_set(&new->refcount, 1);
 155         list_add_rcu(&new->cinfo_list, &fl_cinfo->commits);
 156         list_add(&new->lseg_list, &lseg->pls_commits);
 157         return new;
 158 }
 159 EXPORT_SYMBOL_GPL(pnfs_add_commit_array);
 160
 161 static struct pnfs_commit_array *
 162 pnfs_lookup_commit_array(struct pnfs_ds_commit_info *fl_cinfo,
 163                 struct pnfs_layout_segment *lseg)
 164 {
 165         struct pnfs_commit_array *array;
 166
 167         rcu_read_lock();
 168         array = pnfs_find_commit_array_by_lseg(fl_cinfo, lseg);
 169         if (!array) {
 170                 rcu_read_unlock();
 171                 fl_cinfo->ops->setup_ds_info(fl_cinfo, lseg);
 172                 rcu_read_lock();
 173                 array = pnfs_find_commit_array_by_lseg(fl_cinfo, lseg);
 174         }
 175         rcu_read_unlock();
 176         return array;
 177 }
 178
 179 static void
 180 pnfs_release_commit_array_locked(struct pnfs_commit_array *array)
 181 {
 182         list_del_rcu(&array->cinfo_list);
 183         list_del(&array->lseg_list);
 184         pnfs_free_commit_array(array);
 185 }
 186
 187 static void
 188 pnfs_put_commit_array_locked(struct pnfs_commit_array *array)
 189 {
 190         if (refcount_dec_and_test(&array->refcount))
 191                 pnfs_release_commit_array_locked(array);
 192 }
 193
 194 static void
 195 pnfs_put_commit_array(struct pnfs_commit_array *array, struct inode *inode)
 196 {
 197         if (refcount_dec_and_lock(&array->refcount, &inode->i_lock)) {
 198                 pnfs_release_commit_array_locked(array);
 199                 spin_unlock(&inode->i_lock);
 200         }
 201 }
 202
 203 static struct pnfs_commit_array *
 204 pnfs_get_commit_array(struct pnfs_commit_array *array)
 205 {
 206         if (refcount_inc_not_zero(&array->refcount))
 207                 return array;
 208         return NULL;
 209 }
 210
 211 static void
 212 pnfs_remove_and_free_commit_array(struct pnfs_commit_array *array)
 213 {
 214         array->lseg = NULL;
 215         list_del_init(&array->lseg_list);
 216         pnfs_put_commit_array_locked(array);
 217 }
 218
 219 void
 220 pnfs_generic_ds_cinfo_release_lseg(struct pnfs_ds_commit_info *fl_cinfo,
 221                 struct pnfs_layout_segment *lseg)
 222 {
 223         struct pnfs_commit_array *array, *tmp;
 224
 225         list_for_each_entry_safe(array, tmp, &lseg->pls_commits, lseg_list)
 226                 pnfs_remove_and_free_commit_array(array);
 227 }
 228 EXPORT_SYMBOL_GPL(pnfs_generic_ds_cinfo_release_lseg);
 229
 230 void
 231 pnfs_generic_ds_cinfo_destroy(struct pnfs_ds_commit_info *fl_cinfo)
 232 {
 233         struct pnfs_commit_array *array, *tmp;
 234
 235         list_for_each_entry_safe(array, tmp, &fl_cinfo->commits, cinfo_list)
 236                 pnfs_remove_and_free_commit_array(array);
 237 }
 238 EXPORT_SYMBOL_GPL(pnfs_generic_ds_cinfo_destroy);
 239
 240 /*
 241  * Locks the nfs_page requests for commit and moves them to
 242  * @bucket->committing.
 243  */
 244 static int
 245 pnfs_bucket_scan_ds_commit_list(struct pnfs_commit_bucket *bucket,
 246                                 struct nfs_commit_info *cinfo,
 247                                 int max)
 248 {
 249         struct list_head *src = &bucket->written;
 250         struct list_head *dst = &bucket->committing;
 251         int ret;
 252
 253         lockdep_assert_held(&NFS_I(cinfo->inode)->commit_mutex);
 254         ret = nfs_scan_commit_list(src, dst, cinfo, max);
 255         if (ret) {
 256                 cinfo->ds->nwritten -= ret;
 257                 cinfo->ds->ncommitting += ret;
 258         }
 259         return ret;
 260 }
 261
 262 static int pnfs_bucket_scan_array(struct nfs_commit_info *cinfo,
 263                                   struct pnfs_commit_bucket *buckets,
 264                                   unsigned int nbuckets,
 265                                   int max)
 266 {
 267         unsigned int i;
 268         int rv = 0, cnt;
 269
 270         for (i = 0; i < nbuckets && max != 0; i++) {
 271                 cnt = pnfs_bucket_scan_ds_commit_list(&buckets[i], cinfo, max);
 272                 rv += cnt;
 273                 max -= cnt;
 274         }
 275         return rv;
 276 }
 277
 278 /* Move reqs from written to committing lists, returning count
 279  * of number moved.
 280  */
 281 int pnfs_generic_scan_commit_lists(struct nfs_commit_info *cinfo, int max)
 282 {
 283         struct pnfs_ds_commit_info *fl_cinfo = cinfo->ds;
 284         struct pnfs_commit_array *array;
 285         int rv = 0, cnt;
 286
 287         rcu_read_lock();
 288         list_for_each_entry_rcu(array, &fl_cinfo->commits, cinfo_list) {
 289                 if (!array->lseg || !pnfs_get_commit_array(array))
 290                         continue;
 291                 rcu_read_unlock();
 292                 cnt = pnfs_bucket_scan_array(cinfo, array->buckets,
 293                                 array->nbuckets, max);
 294                 rcu_read_lock();
 295                 pnfs_put_commit_array(array, cinfo->inode);
 296                 rv += cnt;
 297                 max -= cnt;
 298                 if (!max)
 299                         break;
 300         }
 301         rcu_read_unlock();
 302         return rv;
 303 }
 304 EXPORT_SYMBOL_GPL(pnfs_generic_scan_commit_lists);
 305
 306 static unsigned int
 307 pnfs_bucket_recover_commit_reqs(struct list_head *dst,
 308                                 struct pnfs_commit_bucket *buckets,
 309                                 unsigned int nbuckets,
 310                                 struct nfs_commit_info *cinfo)
 311 {
 312         struct pnfs_commit_bucket *b;
 313         struct pnfs_layout_segment *freeme;
 314         unsigned int nwritten, ret = 0;
 315         unsigned int i;
 316
 317 restart:
 318         for (i = 0, b = buckets; i < nbuckets; i++, b++) {
 319                 nwritten = nfs_scan_commit_list(&b->written, dst, cinfo, 0);
 320                 if (!nwritten)
 321                         continue;
 322                 ret += nwritten;
 323                 freeme = pnfs_free_bucket_lseg(b);
 324                 if (freeme) {
 325                         pnfs_put_lseg(freeme);
 326                         goto restart;
 327                 }
 328         }
 329         return ret;
 330 }
 331
 332 /* Pull everything off the committing lists and dump into @dst.  */
 333 void pnfs_generic_recover_commit_reqs(struct list_head *dst,
 334                                       struct nfs_commit_info *cinfo)
 335 {
 336         struct pnfs_ds_commit_info *fl_cinfo = cinfo->ds;
 337         struct pnfs_commit_array *array;
 338         unsigned int nwritten;
 339
 340         lockdep_assert_held(&NFS_I(cinfo->inode)->commit_mutex);
 341         rcu_read_lock();
 342         list_for_each_entry_rcu(array, &fl_cinfo->commits, cinfo_list) {
 343                 if (!array->lseg || !pnfs_get_commit_array(array))
 344                         continue;
 345                 rcu_read_unlock();
 346                 nwritten = pnfs_bucket_recover_commit_reqs(dst,
 347                                                            array->buckets,
 348                                                            array->nbuckets,
 349                                                            cinfo);
 350                 rcu_read_lock();
 351                 pnfs_put_commit_array(array, cinfo->inode);
 352                 fl_cinfo->nwritten -= nwritten;
 353         }
 354         rcu_read_unlock();
 355 }
 356 EXPORT_SYMBOL_GPL(pnfs_generic_recover_commit_reqs);
 357
 358 static struct nfs_page *
 359 pnfs_bucket_search_commit_reqs(struct pnfs_commit_bucket *buckets,
 360                 unsigned int nbuckets, struct page *page)
 361 {
 362         struct nfs_page *req;
 363         struct pnfs_commit_bucket *b;
 364         unsigned int i;
 365
 366         /* Linearly search the commit lists for each bucket until a matching
 367          * request is found */
 368         for (i = 0, b = buckets; i < nbuckets; i++, b++) {
 369                 list_for_each_entry(req, &b->written, wb_list) {
 370                         if (req->wb_page == page)
 371                                 return req->wb_head;
 372                 }
 373                 list_for_each_entry(req, &b->committing, wb_list) {
 374                         if (req->wb_page == page)
 375                                 return req->wb_head;
 376                 }
 377         }
 378         return NULL;
 379 }
 380
 381 /* pnfs_generic_search_commit_reqs - Search lists in @cinfo for the head reqest
 382  *                                 for @page
 383  * @cinfo - commit info for current inode
 384  * @page - page to search for matching head request
 385  *
 386  * Returns a the head request if one is found, otherwise returns NULL.
 387  */
 388 struct nfs_page *
 389 pnfs_generic_search_commit_reqs(struct nfs_commit_info *cinfo, struct page *page)
 390 {
 391         struct pnfs_ds_commit_info *fl_cinfo = cinfo->ds;
 392         struct pnfs_commit_array *array;
 393         struct nfs_page *req;
 394
 395         list_for_each_entry(array, &fl_cinfo->commits, cinfo_list) {
 396                 req = pnfs_bucket_search_commit_reqs(array->buckets,
 397                                 array->nbuckets, page);
 398                 if (req)
 399                         return req;
 400         }
 401         return NULL;
 402 }
 403 EXPORT_SYMBOL_GPL(pnfs_generic_search_commit_reqs);
 404
 405 static struct pnfs_layout_segment *
 406 pnfs_bucket_get_committing(struct list_head *head,
 407                            struct pnfs_commit_bucket *bucket,
 408                            struct nfs_commit_info *cinfo)
 409 {
 410         struct list_head *pos;
 411
 412         list_for_each(pos, &bucket->committing)
 413                 cinfo->ds->ncommitting--;
 414         list_splice_init(&bucket->committing, head);
 415         return pnfs_free_bucket_lseg(bucket);
 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(false);
 423
 424         if (!data)
 425                 return NULL;
 426         data->lseg = pnfs_bucket_get_committing(&data->pages, bucket, cinfo);
 427         if (!data->lseg)
 428                 data->lseg = pnfs_get_lseg(bucket->lseg);
 429         return data;
 430 }
 431
 432 static void pnfs_generic_retry_commit(struct pnfs_commit_bucket *buckets,
 433                                       unsigned int nbuckets,
 434                                       struct nfs_commit_info *cinfo,
 435                                       unsigned int idx)
 436 {
 437         struct pnfs_commit_bucket *bucket;
 438         struct pnfs_layout_segment *freeme;
 439         LIST_HEAD(pages);
 440
 441         for (bucket = buckets; idx < nbuckets; bucket++, idx++) {
 442                 if (list_empty(&bucket->committing))
 443                         continue;
 444                 mutex_lock(&NFS_I(cinfo->inode)->commit_mutex);
 445                 freeme = pnfs_bucket_get_committing(&pages, bucket, cinfo);
 446                 mutex_unlock(&NFS_I(cinfo->inode)->commit_mutex);
 447                 nfs_retry_commit(&pages, freeme, cinfo, idx);
 448                 pnfs_put_lseg(freeme);
 449         }
 450 }
 451
 452 static unsigned int
 453 pnfs_bucket_alloc_ds_commits(struct list_head *list,
 454                              struct pnfs_commit_bucket *buckets,
 455                              unsigned int nbuckets,
 456                              struct nfs_commit_info *cinfo)
 457 {
 458         struct pnfs_commit_bucket *bucket;
 459         struct nfs_commit_data *data;
 460         unsigned int i;
 461         unsigned int nreq = 0;
 462
 463         for (i = 0, bucket = buckets; i < nbuckets; i++, bucket++) {
 464                 if (list_empty(&bucket->committing))
 465                         continue;
 466                 mutex_lock(&NFS_I(cinfo->inode)->commit_mutex);
 467                 if (!list_empty(&bucket->committing)) {
 468                         data = pnfs_bucket_fetch_commitdata(bucket, cinfo);
 469                         if (!data)
 470                                 goto out_error;
 471                         data->ds_commit_index = i;
 472                         list_add_tail(&data->list, list);
 473                         atomic_inc(&cinfo->mds->rpcs_out);
 474                         nreq++;
 475                 }
 476                 mutex_unlock(&NFS_I(cinfo->inode)->commit_mutex);
 477         }
 478         return nreq;
 479 out_error:
 480         mutex_unlock(&NFS_I(cinfo->inode)->commit_mutex);
 481         /* Clean up on error */
 482         pnfs_generic_retry_commit(buckets, nbuckets, cinfo, i);
 483         return nreq;
 484 }
 485
 486 static unsigned int
 487 pnfs_alloc_ds_commits_list(struct list_head *list,
 488                            struct pnfs_ds_commit_info *fl_cinfo,
 489                            struct nfs_commit_info *cinfo)
 490 {
 491         struct pnfs_commit_array *array;
 492         unsigned int ret = 0;
 493
 494         rcu_read_lock();
 495         list_for_each_entry_rcu(array, &fl_cinfo->commits, cinfo_list) {
 496                 if (!array->lseg || !pnfs_get_commit_array(array))
 497                         continue;
 498                 rcu_read_unlock();
 499                 ret += pnfs_bucket_alloc_ds_commits(list, array->buckets,
 500                                 array->nbuckets, cinfo);
 501                 rcu_read_lock();
 502                 pnfs_put_commit_array(array, cinfo->inode);
 503         }
 504         rcu_read_unlock();
 505         return ret;
 506 }
 507
 508 /* This follows nfs_commit_list pretty closely */
 509 int
 510 pnfs_generic_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
 511                              int how, struct nfs_commit_info *cinfo,
 512                              int (*initiate_commit)(struct nfs_commit_data *data,
 513                                                     int how))
 514 {
 515         struct pnfs_ds_commit_info *fl_cinfo = cinfo->ds;
 516         struct nfs_commit_data *data, *tmp;
 517         LIST_HEAD(list);
 518         unsigned int nreq = 0;
 519
 520         if (!list_empty(mds_pages)) {
 521                 data = nfs_commitdata_alloc(true);
 522                 data->ds_commit_index = -1;
 523                 list_splice_init(mds_pages, &data->pages);
 524                 list_add_tail(&data->list, &list);
 525                 atomic_inc(&cinfo->mds->rpcs_out);
 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 void destroy_ds(struct nfs4_pnfs_ds *ds)
 665 {
 666         struct nfs4_pnfs_ds_addr *da;
 667
 668         dprintk("--> %s\n", __func__);
 669         ifdebug(FACILITY)
 670                 print_ds(ds);
 671
 672         nfs_put_client(ds->ds_clp);
 673
 674         while (!list_empty(&ds->ds_addrs)) {
 675                 da = list_first_entry(&ds->ds_addrs,
 676                                       struct nfs4_pnfs_ds_addr,
 677                                       da_node);
 678                 list_del_init(&da->da_node);
 679                 kfree(da->da_remotestr);
 680                 kfree(da);
 681         }
 682
 683         kfree(ds->ds_remotestr);
 684         kfree(ds);
 685 }
 686
 687 void nfs4_pnfs_ds_put(struct nfs4_pnfs_ds *ds)
 688 {
 689         if (refcount_dec_and_lock(&ds->ds_count,
 690                                 &nfs4_ds_cache_lock)) {
 691                 list_del_init(&ds->ds_node);
 692                 spin_unlock(&nfs4_ds_cache_lock);
 693                 destroy_ds(ds);
 694         }
 695 }
 696 EXPORT_SYMBOL_GPL(nfs4_pnfs_ds_put);
 697
 698 /*
 699  * Create a string with a human readable address and port to avoid
 700  * complicated setup around many dprinks.
 701  */
 702 static char *
 703 nfs4_pnfs_remotestr(struct list_head *dsaddrs, gfp_t gfp_flags)
 704 {
 705         struct nfs4_pnfs_ds_addr *da;
 706         char *remotestr;
 707         size_t len;
 708         char *p;
 709
 710         len = 3;        /* '{', '}' and eol */
 711         list_for_each_entry(da, dsaddrs, da_node) {
 712                 len += strlen(da->da_remotestr) + 1;    /* string plus comma */
 713         }
 714
 715         remotestr = kzalloc(len, gfp_flags);
 716         if (!remotestr)
 717                 return NULL;
 718
 719         p = remotestr;
 720         *(p++) = '{';
 721         len--;
 722         list_for_each_entry(da, dsaddrs, da_node) {
 723                 size_t ll = strlen(da->da_remotestr);
 724
 725                 if (ll > len)
 726                         goto out_err;
 727
 728                 memcpy(p, da->da_remotestr, ll);
 729                 p += ll;
 730                 len -= ll;
 731
 732                 if (len < 1)
 733                         goto out_err;
 734                 (*p++) = ',';
 735                 len--;
 736         }
 737         if (len < 2)
 738                 goto out_err;
 739         *(p++) = '}';
 740         *p = '\0';
 741         return remotestr;
 742 out_err:
 743         kfree(remotestr);
 744         return NULL;
 745 }
 746
 747 /*
 748  * Given a list of multipath struct nfs4_pnfs_ds_addr, add it to ds cache if
 749  * uncached and return cached struct nfs4_pnfs_ds.
 750  */
 751 struct nfs4_pnfs_ds *
 752 nfs4_pnfs_ds_add(struct list_head *dsaddrs, gfp_t gfp_flags)
 753 {
 754         struct nfs4_pnfs_ds *tmp_ds, *ds = NULL;
 755         char *remotestr;
 756
 757         if (list_empty(dsaddrs)) {
 758                 dprintk("%s: no addresses defined\n", __func__);
 759                 goto out;
 760         }
 761
 762         ds = kzalloc(sizeof(*ds), gfp_flags);
 763         if (!ds)
 764                 goto out;
 765
 766         /* this is only used for debugging, so it's ok if its NULL */
 767         remotestr = nfs4_pnfs_remotestr(dsaddrs, gfp_flags);
 768
 769         spin_lock(&nfs4_ds_cache_lock);
 770         tmp_ds = _data_server_lookup_locked(dsaddrs);
 771         if (tmp_ds == NULL) {
 772                 INIT_LIST_HEAD(&ds->ds_addrs);
 773                 list_splice_init(dsaddrs, &ds->ds_addrs);
 774                 ds->ds_remotestr = remotestr;
 775                 refcount_set(&ds->ds_count, 1);
 776                 INIT_LIST_HEAD(&ds->ds_node);
 777                 ds->ds_clp = NULL;
 778                 list_add(&ds->ds_node, &nfs4_data_server_cache);
 779                 dprintk("%s add new data server %s\n", __func__,
 780                         ds->ds_remotestr);
 781         } else {
 782                 kfree(remotestr);
 783                 kfree(ds);
 784                 refcount_inc(&tmp_ds->ds_count);
 785                 dprintk("%s data server %s found, inc'ed ds_count to %d\n",
 786                         __func__, tmp_ds->ds_remotestr,
 787                         refcount_read(&tmp_ds->ds_count));
 788                 ds = tmp_ds;
 789         }
 790         spin_unlock(&nfs4_ds_cache_lock);
 791 out:
 792         return ds;
 793 }
 794 EXPORT_SYMBOL_GPL(nfs4_pnfs_ds_add);
 795
 796 static void nfs4_wait_ds_connect(struct nfs4_pnfs_ds *ds)
 797 {
 798         might_sleep();
 799         wait_on_bit(&ds->ds_state, NFS4DS_CONNECTING,
 800                         TASK_KILLABLE);
 801 }
 802
 803 static void nfs4_clear_ds_conn_bit(struct nfs4_pnfs_ds *ds)
 804 {
 805         smp_mb__before_atomic();
 806         clear_bit(NFS4DS_CONNECTING, &ds->ds_state);
 807         smp_mb__after_atomic();
 808         wake_up_bit(&ds->ds_state, NFS4DS_CONNECTING);
 809 }
 810
 811 static struct nfs_client *(*get_v3_ds_connect)(
 812                         struct nfs_server *mds_srv,
 813                         const struct sockaddr *ds_addr,
 814                         int ds_addrlen,
 815                         int ds_proto,
 816                         unsigned int ds_timeo,
 817                         unsigned int ds_retrans);
 818
 819 static bool load_v3_ds_connect(void)
 820 {
 821         if (!get_v3_ds_connect) {
 822                 get_v3_ds_connect = symbol_request(nfs3_set_ds_client);
 823                 WARN_ON_ONCE(!get_v3_ds_connect);
 824         }
 825
 826         return(get_v3_ds_connect != NULL);
 827 }
 828
 829 void nfs4_pnfs_v3_ds_connect_unload(void)
 830 {
 831         if (get_v3_ds_connect) {
 832                 symbol_put(nfs3_set_ds_client);
 833                 get_v3_ds_connect = NULL;
 834         }
 835 }
 836
 837 static int _nfs4_pnfs_v3_ds_connect(struct nfs_server *mds_srv,
 838                                  struct nfs4_pnfs_ds *ds,
 839                                  unsigned int timeo,
 840                                  unsigned int retrans)
 841 {
 842         struct nfs_client *clp = ERR_PTR(-EIO);
 843         struct nfs4_pnfs_ds_addr *da;
 844         int status = 0;
 845
 846         dprintk("--> %s DS %s\n", __func__, ds->ds_remotestr);
 847
 848         if (!load_v3_ds_connect())
 849                 goto out;
 850
 851         list_for_each_entry(da, &ds->ds_addrs, da_node) {
 852                 dprintk("%s: DS %s: trying address %s\n",
 853                         __func__, ds->ds_remotestr, da->da_remotestr);
 854
 855                 if (!IS_ERR(clp)) {
 856                         struct xprt_create xprt_args = {
 857                                 .ident = XPRT_TRANSPORT_TCP,
 858                                 .net = clp->cl_net,
 859                                 .dstaddr = (struct sockaddr *)&da->da_addr,
 860                                 .addrlen = da->da_addrlen,
 861                                 .servername = clp->cl_hostname,
 862                         };
 863                         /* Add this address as an alias */
 864                         rpc_clnt_add_xprt(clp->cl_rpcclient, &xprt_args,
 865                                         rpc_clnt_test_and_add_xprt, NULL);
 866                         continue;
 867                 }
 868                 clp = get_v3_ds_connect(mds_srv,
 869                                 (struct sockaddr *)&da->da_addr,
 870                                 da->da_addrlen, IPPROTO_TCP,
 871                                 timeo, retrans);
 872                 if (IS_ERR(clp))
 873                         continue;
 874                 clp->cl_rpcclient->cl_softerr = 0;
 875                 clp->cl_rpcclient->cl_softrtry = 0;
 876         }
 877
 878         if (IS_ERR(clp)) {
 879                 status = PTR_ERR(clp);
 880                 goto out;
 881         }
 882
 883         smp_wmb();
 884         ds->ds_clp = clp;
 885         dprintk("%s [new] addr: %s\n", __func__, ds->ds_remotestr);
 886 out:
 887         return status;
 888 }
 889
 890 static int _nfs4_pnfs_v4_ds_connect(struct nfs_server *mds_srv,
 891                                  struct nfs4_pnfs_ds *ds,
 892                                  unsigned int timeo,
 893                                  unsigned int retrans,
 894                                  u32 minor_version)
 895 {
 896         struct nfs_client *clp = ERR_PTR(-EIO);
 897         struct nfs4_pnfs_ds_addr *da;
 898         int status = 0;
 899
 900         dprintk("--> %s DS %s\n", __func__, ds->ds_remotestr);
 901
 902         list_for_each_entry(da, &ds->ds_addrs, da_node) {
 903                 dprintk("%s: DS %s: trying address %s\n",
 904                         __func__, ds->ds_remotestr, da->da_remotestr);
 905
 906                 if (!IS_ERR(clp) && clp->cl_mvops->session_trunk) {
 907                         struct xprt_create xprt_args = {
 908                                 .ident = XPRT_TRANSPORT_TCP,
 909                                 .net = clp->cl_net,
 910                                 .dstaddr = (struct sockaddr *)&da->da_addr,
 911                                 .addrlen = da->da_addrlen,
 912                                 .servername = clp->cl_hostname,
 913                         };
 914                         struct nfs4_add_xprt_data xprtdata = {
 915                                 .clp = clp,
 916                                 .cred = nfs4_get_clid_cred(clp),
 917                         };
 918                         struct rpc_add_xprt_test rpcdata = {
 919                                 .add_xprt_test = clp->cl_mvops->session_trunk,
 920                                 .data = &xprtdata,
 921                         };
 922
 923                         /**
 924                         * Test this address for session trunking and
 925                         * add as an alias
 926                         */
 927                         rpc_clnt_add_xprt(clp->cl_rpcclient, &xprt_args,
 928                                           rpc_clnt_setup_test_and_add_xprt,
 929                                           &rpcdata);
 930                         if (xprtdata.cred)
 931                                 put_cred(xprtdata.cred);
 932                 } else {
 933                         clp = nfs4_set_ds_client(mds_srv,
 934                                                 (struct sockaddr *)&da->da_addr,
 935                                                 da->da_addrlen, IPPROTO_TCP,
 936                                                 timeo, retrans, minor_version);
 937                         if (IS_ERR(clp))
 938                                 continue;
 939
 940                         status = nfs4_init_ds_session(clp,
 941                                         mds_srv->nfs_client->cl_lease_time);
 942                         if (status) {
 943                                 nfs_put_client(clp);
 944                                 clp = ERR_PTR(-EIO);
 945                                 continue;
 946                         }
 947
 948                 }
 949         }
 950
 951         if (IS_ERR(clp)) {
 952                 status = PTR_ERR(clp);
 953                 goto out;
 954         }
 955
 956         smp_wmb();
 957         ds->ds_clp = clp;
 958         dprintk("%s [new] addr: %s\n", __func__, ds->ds_remotestr);
 959 out:
 960         return status;
 961 }
 962
 963 /*
 964  * Create an rpc connection to the nfs4_pnfs_ds data server.
 965  * Currently only supports IPv4 and IPv6 addresses.
 966  * If connection fails, make devid unavailable and return a -errno.
 967  */
 968 int nfs4_pnfs_ds_connect(struct nfs_server *mds_srv, struct nfs4_pnfs_ds *ds,
 969                           struct nfs4_deviceid_node *devid, unsigned int timeo,
 970                           unsigned int retrans, u32 version, u32 minor_version)
 971 {
 972         int err;
 973
 974 again:
 975         err = 0;
 976         if (test_and_set_bit(NFS4DS_CONNECTING, &ds->ds_state) == 0) {
 977                 if (version == 3) {
 978                         err = _nfs4_pnfs_v3_ds_connect(mds_srv, ds, timeo,
 979                                                        retrans);
 980                 } else if (version == 4) {
 981                         err = _nfs4_pnfs_v4_ds_connect(mds_srv, ds, timeo,
 982                                                        retrans, minor_version);
 983                 } else {
 984                         dprintk("%s: unsupported DS version %d\n", __func__,
 985                                 version);
 986                         err = -EPROTONOSUPPORT;
 987                 }
 988
 989                 nfs4_clear_ds_conn_bit(ds);
 990         } else {
 991                 nfs4_wait_ds_connect(ds);
 992
 993                 /* what was waited on didn't connect AND didn't mark unavail */
 994                 if (!ds->ds_clp && !nfs4_test_deviceid_unavailable(devid))
 995                         goto again;
 996         }
 997
 998         /*
 999          * At this point the ds->ds_clp should be ready, but it might have
1000          * hit an error.
1001          */
1002         if (!err) {
1003                 if (!ds->ds_clp || !nfs_client_init_is_complete(ds->ds_clp)) {
1004                         WARN_ON_ONCE(ds->ds_clp ||
1005                                 !nfs4_test_deviceid_unavailable(devid));
1006                         return -EINVAL;
1007                 }
1008                 err = nfs_client_init_status(ds->ds_clp);
1009         }
1010
1011         return err;
1012 }
1013 EXPORT_SYMBOL_GPL(nfs4_pnfs_ds_connect);
1014
1015 /*
1016  * Currently only supports ipv4, ipv6 and one multi-path address.
1017  */
1018 struct nfs4_pnfs_ds_addr *
1019 nfs4_decode_mp_ds_addr(struct net *net, struct xdr_stream *xdr, gfp_t gfp_flags)
1020 {
1021         struct nfs4_pnfs_ds_addr *da = NULL;
1022         char *buf, *portstr;
1023         __be16 port;
1024         int nlen, rlen;
1025         int tmp[2];
1026         __be32 *p;
1027         char *netid, *match_netid;
1028         size_t len, match_netid_len;
1029         char *startsep = "";
1030         char *endsep = "";
1031
1032
1033         /* r_netid */
1034         p = xdr_inline_decode(xdr, 4);
1035         if (unlikely(!p))
1036                 goto out_err;
1037         nlen = be32_to_cpup(p++);
1038
1039         p = xdr_inline_decode(xdr, nlen);
1040         if (unlikely(!p))
1041                 goto out_err;
1042
1043         netid = kmalloc(nlen+1, gfp_flags);
1044         if (unlikely(!netid))
1045                 goto out_err;
1046
1047         netid[nlen] = '\0';
1048         memcpy(netid, p, nlen);
1049
1050         /* r_addr: ip/ip6addr with port in dec octets - see RFC 5665 */
1051         p = xdr_inline_decode(xdr, 4);
1052         if (unlikely(!p))
1053                 goto out_free_netid;
1054         rlen = be32_to_cpup(p);
1055
1056         p = xdr_inline_decode(xdr, rlen);
1057         if (unlikely(!p))
1058                 goto out_free_netid;
1059
1060         /* port is ".ABC.DEF", 8 chars max */
1061         if (rlen > INET6_ADDRSTRLEN + IPV6_SCOPE_ID_LEN + 8) {
1062                 dprintk("%s: Invalid address, length %d\n", __func__,
1063                         rlen);
1064                 goto out_free_netid;
1065         }
1066         buf = kmalloc(rlen + 1, gfp_flags);
1067         if (!buf) {
1068                 dprintk("%s: Not enough memory\n", __func__);
1069                 goto out_free_netid;
1070         }
1071         buf[rlen] = '\0';
1072         memcpy(buf, p, rlen);
1073
1074         /* replace port '.' with '-' */
1075         portstr = strrchr(buf, '.');
1076         if (!portstr) {
1077                 dprintk("%s: Failed finding expected dot in port\n",
1078                         __func__);
1079                 goto out_free_buf;
1080         }
1081         *portstr = '-';
1082
1083         /* find '.' between address and port */
1084         portstr = strrchr(buf, '.');
1085         if (!portstr) {
1086                 dprintk("%s: Failed finding expected dot between address and "
1087                         "port\n", __func__);
1088                 goto out_free_buf;
1089         }
1090         *portstr = '\0';
1091
1092         da = kzalloc(sizeof(*da), gfp_flags);
1093         if (unlikely(!da))
1094                 goto out_free_buf;
1095
1096         INIT_LIST_HEAD(&da->da_node);
1097
1098         if (!rpc_pton(net, buf, portstr-buf, (struct sockaddr *)&da->da_addr,
1099                       sizeof(da->da_addr))) {
1100                 dprintk("%s: error parsing address %s\n", __func__, buf);
1101                 goto out_free_da;
1102         }
1103
1104         portstr++;
1105         sscanf(portstr, "%d-%d", &tmp[0], &tmp[1]);
1106         port = htons((tmp[0] << 8) | (tmp[1]));
1107
1108         switch (da->da_addr.ss_family) {
1109         case AF_INET:
1110                 ((struct sockaddr_in *)&da->da_addr)->sin_port = port;
1111                 da->da_addrlen = sizeof(struct sockaddr_in);
1112                 match_netid = "tcp";
1113                 match_netid_len = 3;
1114                 break;
1115
1116         case AF_INET6:
1117                 ((struct sockaddr_in6 *)&da->da_addr)->sin6_port = port;
1118                 da->da_addrlen = sizeof(struct sockaddr_in6);
1119                 match_netid = "tcp6";
1120                 match_netid_len = 4;
1121                 startsep = "[";
1122                 endsep = "]";
1123                 break;
1124
1125         default:
1126                 dprintk("%s: unsupported address family: %u\n",
1127                         __func__, da->da_addr.ss_family);
1128                 goto out_free_da;
1129         }
1130
1131         if (nlen != match_netid_len || strncmp(netid, match_netid, nlen)) {
1132                 dprintk("%s: ERROR: r_netid \"%s\" != \"%s\"\n",
1133                         __func__, netid, match_netid);
1134                 goto out_free_da;
1135         }
1136
1137         /* save human readable address */
1138         len = strlen(startsep) + strlen(buf) + strlen(endsep) + 7;
1139         da->da_remotestr = kzalloc(len, gfp_flags);
1140
1141         /* NULL is ok, only used for dprintk */
1142         if (da->da_remotestr)
1143                 snprintf(da->da_remotestr, len, "%s%s%s:%u", startsep,
1144                          buf, endsep, ntohs(port));
1145
1146         dprintk("%s: Parsed DS addr %s\n", __func__, da->da_remotestr);
1147         kfree(buf);
1148         kfree(netid);
1149         return da;
1150
1151 out_free_da:
1152         kfree(da);
1153 out_free_buf:
1154         dprintk("%s: Error parsing DS addr: %s\n", __func__, buf);
1155         kfree(buf);
1156 out_free_netid:
1157         kfree(netid);
1158 out_err:
1159         return NULL;
1160 }
1161 EXPORT_SYMBOL_GPL(nfs4_decode_mp_ds_addr);
1162
1163 void
1164 pnfs_layout_mark_request_commit(struct nfs_page *req,
1165                                 struct pnfs_layout_segment *lseg,
1166                                 struct nfs_commit_info *cinfo,
1167                                 u32 ds_commit_idx)
1168 {
1169         struct list_head *list;
1170         struct pnfs_commit_array *array;
1171         struct pnfs_commit_bucket *bucket;
1172
1173         mutex_lock(&NFS_I(cinfo->inode)->commit_mutex);
1174         array = pnfs_lookup_commit_array(cinfo->ds, lseg);
1175         if (!array || !pnfs_is_valid_lseg(lseg))
1176                 goto out_resched;
1177         bucket = &array->buckets[ds_commit_idx];
1178         list = &bucket->written;
1179         /* Non-empty buckets hold a reference on the lseg.  That ref
1180          * is normally transferred to the COMMIT call and released
1181          * there.  It could also be released if the last req is pulled
1182          * off due to a rewrite, in which case it will be done in
1183          * pnfs_common_clear_request_commit
1184          */
1185         if (!bucket->lseg)
1186                 bucket->lseg = pnfs_get_lseg(lseg);
1187         set_bit(PG_COMMIT_TO_DS, &req->wb_flags);
1188         cinfo->ds->nwritten++;
1189
1190         nfs_request_add_commit_list_locked(req, list, cinfo);
1191         mutex_unlock(&NFS_I(cinfo->inode)->commit_mutex);
1192         nfs_mark_page_unstable(req->wb_page, cinfo);
1193         return;
1194 out_resched:
1195         mutex_unlock(&NFS_I(cinfo->inode)->commit_mutex);
1196         cinfo->completion_ops->resched_write(cinfo, req);
1197 }
1198 EXPORT_SYMBOL_GPL(pnfs_layout_mark_request_commit);
1199
1200 int
1201 pnfs_nfs_generic_sync(struct inode *inode, bool datasync)
1202 {
1203         int ret;
1204
1205         if (!pnfs_layoutcommit_outstanding(inode))
1206                 return 0;
1207         ret = nfs_commit_inode(inode, FLUSH_SYNC);
1208         if (ret < 0)
1209                 return ret;
1210         if (datasync)
1211                 return 0;
1212         return pnfs_layoutcommit_inode(inode, true);
1213 }
1214 EXPORT_SYMBOL_GPL(pnfs_nfs_generic_sync);
1215