fs/nfs/pnfs_nfs.c

   1 /*
   2  * Common NFS I/O  operations for the pnfs file based
   3  * layout drivers.
   4  *
   5  * Copyright (c) 2014, Primary Data, Inc. All rights reserved.
   6  *
   7  * Tom Haynes <loghyr@primarydata.com>
   8  */
   9
  10 #include <linux/nfs_fs.h>
  11 #include <linux/nfs_page.h>
  12 #include <linux/sunrpc/addr.h>
  13 #include <linux/module.h>
  14
  15 #include "nfs4session.h"
  16 #include "internal.h"
  17 #include "pnfs.h"
  18
  19 #define NFSDBG_FACILITY         NFSDBG_PNFS
  20
  21 void pnfs_generic_rw_release(void *data)
  22 {
  23         struct nfs_pgio_header *hdr = data;
  24
  25         nfs_put_client(hdr->ds_clp);
  26         hdr->mds_ops->rpc_release(data);
  27 }
  28 EXPORT_SYMBOL_GPL(pnfs_generic_rw_release);
  29
  30 /* Fake up some data that will cause nfs_commit_release to retry the writes. */
  31 void pnfs_generic_prepare_to_resend_writes(struct nfs_commit_data *data)
  32 {
  33         struct nfs_page *first = nfs_list_entry(data->pages.next);
  34
  35         data->task.tk_status = 0;
  36         memcpy(&data->verf.verifier, &first->wb_verf,
  37                sizeof(data->verf.verifier));
  38         data->verf.verifier.data[0]++; /* ensure verifier mismatch */
  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 /* The generic layer is about to remove the req from the commit list.
  63  * If this will make the bucket empty, it will need to put the lseg reference.
  64  * Note this must be called holding i_lock
  65  */
  66 void
  67 pnfs_generic_clear_request_commit(struct nfs_page *req,
  68                                   struct nfs_commit_info *cinfo)
  69 {
  70         struct pnfs_layout_segment *freeme = NULL;
  71
  72         if (!test_and_clear_bit(PG_COMMIT_TO_DS, &req->wb_flags))
  73                 goto out;
  74         cinfo->ds->nwritten--;
  75         if (list_is_singular(&req->wb_list)) {
  76                 struct pnfs_commit_bucket *bucket;
  77
  78                 bucket = list_first_entry(&req->wb_list,
  79                                           struct pnfs_commit_bucket,
  80                                           written);
  81                 freeme = bucket->wlseg;
  82                 bucket->wlseg = NULL;
  83         }
  84 out:
  85         nfs_request_remove_commit_list(req, cinfo);
  86         pnfs_put_lseg_locked(freeme);
  87 }
  88 EXPORT_SYMBOL_GPL(pnfs_generic_clear_request_commit);
  89
  90 static int
  91 pnfs_generic_transfer_commit_list(struct list_head *src, struct list_head *dst,
  92                                   struct nfs_commit_info *cinfo, int max)
  93 {
  94         struct nfs_page *req, *tmp;
  95         int ret = 0;
  96
  97         list_for_each_entry_safe(req, tmp, src, wb_list) {
  98                 if (!nfs_lock_request(req))
  99                         continue;
 100                 kref_get(&req->wb_kref);
 101                 if (cond_resched_lock(&cinfo->inode->i_lock))
 102                         list_safe_reset_next(req, tmp, wb_list);
 103                 nfs_request_remove_commit_list(req, cinfo);
 104                 clear_bit(PG_COMMIT_TO_DS, &req->wb_flags);
 105                 nfs_list_add_request(req, dst);
 106                 ret++;
 107                 if ((ret == max) && !cinfo->dreq)
 108                         break;
 109         }
 110         return ret;
 111 }
 112
 113 static int
 114 pnfs_generic_scan_ds_commit_list(struct pnfs_commit_bucket *bucket,
 115                                  struct nfs_commit_info *cinfo,
 116                                  int max)
 117 {
 118         struct list_head *src = &bucket->written;
 119         struct list_head *dst = &bucket->committing;
 120         int ret;
 121
 122         lockdep_assert_held(&cinfo->inode->i_lock);
 123         ret = pnfs_generic_transfer_commit_list(src, dst, cinfo, max);
 124         if (ret) {
 125                 cinfo->ds->nwritten -= ret;
 126                 cinfo->ds->ncommitting += ret;
 127                 if (bucket->clseg == NULL)
 128                         bucket->clseg = pnfs_get_lseg(bucket->wlseg);
 129                 if (list_empty(src)) {
 130                         pnfs_put_lseg_locked(bucket->wlseg);
 131                         bucket->wlseg = NULL;
 132                 }
 133         }
 134         return ret;
 135 }
 136
 137 /* Move reqs from written to committing lists, returning count
 138  * of number moved.
 139  */
 140 int pnfs_generic_scan_commit_lists(struct nfs_commit_info *cinfo,
 141                                    int max)
 142 {
 143         int i, rv = 0, cnt;
 144
 145         lockdep_assert_held(&cinfo->inode->i_lock);
 146         for (i = 0; i < cinfo->ds->nbuckets && max != 0; i++) {
 147                 cnt = pnfs_generic_scan_ds_commit_list(&cinfo->ds->buckets[i],
 148                                                        cinfo, max);
 149                 max -= cnt;
 150                 rv += cnt;
 151         }
 152         return rv;
 153 }
 154 EXPORT_SYMBOL_GPL(pnfs_generic_scan_commit_lists);
 155
 156 /* Pull everything off the committing lists and dump into @dst.  */
 157 void pnfs_generic_recover_commit_reqs(struct list_head *dst,
 158                                       struct nfs_commit_info *cinfo)
 159 {
 160         struct pnfs_commit_bucket *b;
 161         struct pnfs_layout_segment *freeme;
 162         int i;
 163
 164         lockdep_assert_held(&cinfo->inode->i_lock);
 165 restart:
 166         for (i = 0, b = cinfo->ds->buckets; i < cinfo->ds->nbuckets; i++, b++) {
 167                 if (pnfs_generic_transfer_commit_list(&b->written, dst,
 168                                                       cinfo, 0)) {
 169                         freeme = b->wlseg;
 170                         b->wlseg = NULL;
 171                         spin_unlock(&cinfo->inode->i_lock);
 172                         pnfs_put_lseg(freeme);
 173                         spin_lock(&cinfo->inode->i_lock);
 174                         goto restart;
 175                 }
 176         }
 177         cinfo->ds->nwritten = 0;
 178 }
 179 EXPORT_SYMBOL_GPL(pnfs_generic_recover_commit_reqs);
 180
 181 static void pnfs_generic_retry_commit(struct nfs_commit_info *cinfo, int idx)
 182 {
 183         struct pnfs_ds_commit_info *fl_cinfo = cinfo->ds;
 184         struct pnfs_commit_bucket *bucket;
 185         struct pnfs_layout_segment *freeme;
 186         LIST_HEAD(pages);
 187         int i;
 188
 189         spin_lock(&cinfo->inode->i_lock);
 190         for (i = idx; i < fl_cinfo->nbuckets; i++) {
 191                 bucket = &fl_cinfo->buckets[i];
 192                 if (list_empty(&bucket->committing))
 193                         continue;
 194                 freeme = bucket->clseg;
 195                 bucket->clseg = NULL;
 196                 list_splice_init(&bucket->committing, &pages);
 197                 spin_unlock(&cinfo->inode->i_lock);
 198                 nfs_retry_commit(&pages, freeme, cinfo, i);
 199                 pnfs_put_lseg(freeme);
 200                 spin_lock(&cinfo->inode->i_lock);
 201         }
 202         spin_unlock(&cinfo->inode->i_lock);
 203 }
 204
 205 static unsigned int
 206 pnfs_generic_alloc_ds_commits(struct nfs_commit_info *cinfo,
 207                               struct list_head *list)
 208 {
 209         struct pnfs_ds_commit_info *fl_cinfo;
 210         struct pnfs_commit_bucket *bucket;
 211         struct nfs_commit_data *data;
 212         int i;
 213         unsigned int nreq = 0;
 214
 215         fl_cinfo = cinfo->ds;
 216         bucket = fl_cinfo->buckets;
 217         for (i = 0; i < fl_cinfo->nbuckets; i++, bucket++) {
 218                 if (list_empty(&bucket->committing))
 219                         continue;
 220                 data = nfs_commitdata_alloc();
 221                 if (!data)
 222                         break;
 223                 data->ds_commit_index = i;
 224                 list_add(&data->pages, list);
 225                 nreq++;
 226         }
 227
 228         /* Clean up on error */
 229         pnfs_generic_retry_commit(cinfo, i);
 230         return nreq;
 231 }
 232
 233 static inline
 234 void pnfs_fetch_commit_bucket_list(struct list_head *pages,
 235                 struct nfs_commit_data *data,
 236                 struct nfs_commit_info *cinfo)
 237 {
 238         struct pnfs_commit_bucket *bucket;
 239
 240         bucket = &cinfo->ds->buckets[data->ds_commit_index];
 241         spin_lock(&cinfo->inode->i_lock);
 242         list_splice_init(&bucket->committing, pages);
 243         data->lseg = bucket->clseg;
 244         bucket->clseg = NULL;
 245         spin_unlock(&cinfo->inode->i_lock);
 246
 247 }
 248
 249 /* Helper function for pnfs_generic_commit_pagelist to catch an empty
 250  * page list. This can happen when two commits race.
 251  *
 252  * This must be called instead of nfs_init_commit - call one or the other, but
 253  * not both!
 254  */
 255 static bool
 256 pnfs_generic_commit_cancel_empty_pagelist(struct list_head *pages,
 257                                           struct nfs_commit_data *data,
 258                                           struct nfs_commit_info *cinfo)
 259 {
 260         if (list_empty(pages)) {
 261                 if (atomic_dec_and_test(&cinfo->mds->rpcs_out))
 262                         wake_up_atomic_t(&cinfo->mds->rpcs_out);
 263                 /* don't call nfs_commitdata_release - it tries to put
 264                  * the open_context which is not acquired until nfs_init_commit
 265                  * which has not been called on @data */
 266                 WARN_ON_ONCE(data->context);
 267                 nfs_commit_free(data);
 268                 return true;
 269         }
 270
 271         return false;
 272 }
 273
 274 /* This follows nfs_commit_list pretty closely */
 275 int
 276 pnfs_generic_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
 277                              int how, struct nfs_commit_info *cinfo,
 278                              int (*initiate_commit)(struct nfs_commit_data *data,
 279                                                     int how))
 280 {
 281         struct nfs_commit_data *data, *tmp;
 282         LIST_HEAD(list);
 283         unsigned int nreq = 0;
 284
 285         if (!list_empty(mds_pages)) {
 286                 data = nfs_commitdata_alloc();
 287                 if (data != NULL) {
 288                         data->ds_commit_index = -1;
 289                         list_add(&data->pages, &list);
 290                         nreq++;
 291                 } else {
 292                         nfs_retry_commit(mds_pages, NULL, cinfo, 0);
 293                         pnfs_generic_retry_commit(cinfo, 0);
 294                         return -ENOMEM;
 295                 }
 296         }
 297
 298         nreq += pnfs_generic_alloc_ds_commits(cinfo, &list);
 299
 300         if (nreq == 0)
 301                 goto out;
 302
 303         atomic_add(nreq, &cinfo->mds->rpcs_out);
 304
 305         list_for_each_entry_safe(data, tmp, &list, pages) {
 306                 list_del_init(&data->pages);
 307                 if (data->ds_commit_index < 0) {
 308                         /* another commit raced with us */
 309                         if (pnfs_generic_commit_cancel_empty_pagelist(mds_pages,
 310                                 data, cinfo))
 311                                 continue;
 312
 313                         nfs_init_commit(data, mds_pages, NULL, cinfo);
 314                         nfs_initiate_commit(NFS_CLIENT(inode), data,
 315                                             NFS_PROTO(data->inode),
 316                                             data->mds_ops, how, 0);
 317                 } else {
 318                         LIST_HEAD(pages);
 319
 320                         pnfs_fetch_commit_bucket_list(&pages, data, cinfo);
 321
 322                         /* another commit raced with us */
 323                         if (pnfs_generic_commit_cancel_empty_pagelist(&pages,
 324                                 data, cinfo))
 325                                 continue;
 326
 327                         nfs_init_commit(data, &pages, data->lseg, cinfo);
 328                         initiate_commit(data, how);
 329                 }
 330         }
 331 out:
 332         cinfo->ds->ncommitting = 0;
 333         return PNFS_ATTEMPTED;
 334 }
 335 EXPORT_SYMBOL_GPL(pnfs_generic_commit_pagelist);
 336
 337 /*
 338  * Data server cache
 339  *
 340  * Data servers can be mapped to different device ids.
 341  * nfs4_pnfs_ds reference counting
 342  *   - set to 1 on allocation
 343  *   - incremented when a device id maps a data server already in the cache.
 344  *   - decremented when deviceid is removed from the cache.
 345  */
 346 static DEFINE_SPINLOCK(nfs4_ds_cache_lock);
 347 static LIST_HEAD(nfs4_data_server_cache);
 348
 349 /* Debug routines */
 350 static void
 351 print_ds(struct nfs4_pnfs_ds *ds)
 352 {
 353         if (ds == NULL) {
 354                 printk(KERN_WARNING "%s NULL device\n", __func__);
 355                 return;
 356         }
 357         printk(KERN_WARNING "        ds %s\n"
 358                 "        ref count %d\n"
 359                 "        client %p\n"
 360                 "        cl_exchange_flags %x\n",
 361                 ds->ds_remotestr,
 362                 atomic_read(&ds->ds_count), ds->ds_clp,
 363                 ds->ds_clp ? ds->ds_clp->cl_exchange_flags : 0);
 364 }
 365
 366 static bool
 367 same_sockaddr(struct sockaddr *addr1, struct sockaddr *addr2)
 368 {
 369         struct sockaddr_in *a, *b;
 370         struct sockaddr_in6 *a6, *b6;
 371
 372         if (addr1->sa_family != addr2->sa_family)
 373                 return false;
 374
 375         switch (addr1->sa_family) {
 376         case AF_INET:
 377                 a = (struct sockaddr_in *)addr1;
 378                 b = (struct sockaddr_in *)addr2;
 379
 380                 if (a->sin_addr.s_addr == b->sin_addr.s_addr &&
 381                     a->sin_port == b->sin_port)
 382                         return true;
 383                 break;
 384
 385         case AF_INET6:
 386                 a6 = (struct sockaddr_in6 *)addr1;
 387                 b6 = (struct sockaddr_in6 *)addr2;
 388
 389                 /* LINKLOCAL addresses must have matching scope_id */
 390                 if (ipv6_addr_src_scope(&a6->sin6_addr) ==
 391                     IPV6_ADDR_SCOPE_LINKLOCAL &&
 392                     a6->sin6_scope_id != b6->sin6_scope_id)
 393                         return false;
 394
 395                 if (ipv6_addr_equal(&a6->sin6_addr, &b6->sin6_addr) &&
 396                     a6->sin6_port == b6->sin6_port)
 397                         return true;
 398                 break;
 399
 400         default:
 401                 dprintk("%s: unhandled address family: %u\n",
 402                         __func__, addr1->sa_family);
 403                 return false;
 404         }
 405
 406         return false;
 407 }
 408
 409 /*
 410  * Checks if 'dsaddrs1' contains a subset of 'dsaddrs2'. If it does,
 411  * declare a match.
 412  */
 413 static bool
 414 _same_data_server_addrs_locked(const struct list_head *dsaddrs1,
 415                                const struct list_head *dsaddrs2)
 416 {
 417         struct nfs4_pnfs_ds_addr *da1, *da2;
 418         struct sockaddr *sa1, *sa2;
 419         bool match = false;
 420
 421         list_for_each_entry(da1, dsaddrs1, da_node) {
 422                 sa1 = (struct sockaddr *)&da1->da_addr;
 423                 match = false;
 424                 list_for_each_entry(da2, dsaddrs2, da_node) {
 425                         sa2 = (struct sockaddr *)&da2->da_addr;
 426                         match = same_sockaddr(sa1, sa2);
 427                         if (match)
 428                                 break;
 429                 }
 430                 if (!match)
 431                         break;
 432         }
 433         return match;
 434 }
 435
 436 /*
 437  * Lookup DS by addresses.  nfs4_ds_cache_lock is held
 438  */
 439 static struct nfs4_pnfs_ds *
 440 _data_server_lookup_locked(const struct list_head *dsaddrs)
 441 {
 442         struct nfs4_pnfs_ds *ds;
 443
 444         list_for_each_entry(ds, &nfs4_data_server_cache, ds_node)
 445                 if (_same_data_server_addrs_locked(&ds->ds_addrs, dsaddrs))
 446                         return ds;
 447         return NULL;
 448 }
 449
 450 static void destroy_ds(struct nfs4_pnfs_ds *ds)
 451 {
 452         struct nfs4_pnfs_ds_addr *da;
 453
 454         dprintk("--> %s\n", __func__);
 455         ifdebug(FACILITY)
 456                 print_ds(ds);
 457
 458         nfs_put_client(ds->ds_clp);
 459
 460         while (!list_empty(&ds->ds_addrs)) {
 461                 da = list_first_entry(&ds->ds_addrs,
 462                                       struct nfs4_pnfs_ds_addr,
 463                                       da_node);
 464                 list_del_init(&da->da_node);
 465                 kfree(da->da_remotestr);
 466                 kfree(da);
 467         }
 468
 469         kfree(ds->ds_remotestr);
 470         kfree(ds);
 471 }
 472
 473 void nfs4_pnfs_ds_put(struct nfs4_pnfs_ds *ds)
 474 {
 475         if (atomic_dec_and_lock(&ds->ds_count,
 476                                 &nfs4_ds_cache_lock)) {
 477                 list_del_init(&ds->ds_node);
 478                 spin_unlock(&nfs4_ds_cache_lock);
 479                 destroy_ds(ds);
 480         }
 481 }
 482 EXPORT_SYMBOL_GPL(nfs4_pnfs_ds_put);
 483
 484 /*
 485  * Create a string with a human readable address and port to avoid
 486  * complicated setup around many dprinks.
 487  */
 488 static char *
 489 nfs4_pnfs_remotestr(struct list_head *dsaddrs, gfp_t gfp_flags)
 490 {
 491         struct nfs4_pnfs_ds_addr *da;
 492         char *remotestr;
 493         size_t len;
 494         char *p;
 495
 496         len = 3;        /* '{', '}' and eol */
 497         list_for_each_entry(da, dsaddrs, da_node) {
 498                 len += strlen(da->da_remotestr) + 1;    /* string plus comma */
 499         }
 500
 501         remotestr = kzalloc(len, gfp_flags);
 502         if (!remotestr)
 503                 return NULL;
 504
 505         p = remotestr;
 506         *(p++) = '{';
 507         len--;
 508         list_for_each_entry(da, dsaddrs, da_node) {
 509                 size_t ll = strlen(da->da_remotestr);
 510
 511                 if (ll > len)
 512                         goto out_err;
 513
 514                 memcpy(p, da->da_remotestr, ll);
 515                 p += ll;
 516                 len -= ll;
 517
 518                 if (len < 1)
 519                         goto out_err;
 520                 (*p++) = ',';
 521                 len--;
 522         }
 523         if (len < 2)
 524                 goto out_err;
 525         *(p++) = '}';
 526         *p = '\0';
 527         return remotestr;
 528 out_err:
 529         kfree(remotestr);
 530         return NULL;
 531 }
 532
 533 /*
 534  * Given a list of multipath struct nfs4_pnfs_ds_addr, add it to ds cache if
 535  * uncached and return cached struct nfs4_pnfs_ds.
 536  */
 537 struct nfs4_pnfs_ds *
 538 nfs4_pnfs_ds_add(struct list_head *dsaddrs, gfp_t gfp_flags)
 539 {
 540         struct nfs4_pnfs_ds *tmp_ds, *ds = NULL;
 541         char *remotestr;
 542
 543         if (list_empty(dsaddrs)) {
 544                 dprintk("%s: no addresses defined\n", __func__);
 545                 goto out;
 546         }
 547
 548         ds = kzalloc(sizeof(*ds), gfp_flags);
 549         if (!ds)
 550                 goto out;
 551
 552         /* this is only used for debugging, so it's ok if its NULL */
 553         remotestr = nfs4_pnfs_remotestr(dsaddrs, gfp_flags);
 554
 555         spin_lock(&nfs4_ds_cache_lock);
 556         tmp_ds = _data_server_lookup_locked(dsaddrs);
 557         if (tmp_ds == NULL) {
 558                 INIT_LIST_HEAD(&ds->ds_addrs);
 559                 list_splice_init(dsaddrs, &ds->ds_addrs);
 560                 ds->ds_remotestr = remotestr;
 561                 atomic_set(&ds->ds_count, 1);
 562                 INIT_LIST_HEAD(&ds->ds_node);
 563                 ds->ds_clp = NULL;
 564                 list_add(&ds->ds_node, &nfs4_data_server_cache);
 565                 dprintk("%s add new data server %s\n", __func__,
 566                         ds->ds_remotestr);
 567         } else {
 568                 kfree(remotestr);
 569                 kfree(ds);
 570                 atomic_inc(&tmp_ds->ds_count);
 571                 dprintk("%s data server %s found, inc'ed ds_count to %d\n",
 572                         __func__, tmp_ds->ds_remotestr,
 573                         atomic_read(&tmp_ds->ds_count));
 574                 ds = tmp_ds;
 575         }
 576         spin_unlock(&nfs4_ds_cache_lock);
 577 out:
 578         return ds;
 579 }
 580 EXPORT_SYMBOL_GPL(nfs4_pnfs_ds_add);
 581
 582 static void nfs4_wait_ds_connect(struct nfs4_pnfs_ds *ds)
 583 {
 584         might_sleep();
 585         wait_on_bit(&ds->ds_state, NFS4DS_CONNECTING,
 586                         TASK_KILLABLE);
 587 }
 588
 589 static void nfs4_clear_ds_conn_bit(struct nfs4_pnfs_ds *ds)
 590 {
 591         smp_mb__before_atomic();
 592         clear_bit(NFS4DS_CONNECTING, &ds->ds_state);
 593         smp_mb__after_atomic();
 594         wake_up_bit(&ds->ds_state, NFS4DS_CONNECTING);
 595 }
 596
 597 static struct nfs_client *(*get_v3_ds_connect)(
 598                         struct nfs_server *mds_srv,
 599                         const struct sockaddr *ds_addr,
 600                         int ds_addrlen,
 601                         int ds_proto,
 602                         unsigned int ds_timeo,
 603                         unsigned int ds_retrans,
 604                         rpc_authflavor_t au_flavor);
 605
 606 static bool load_v3_ds_connect(void)
 607 {
 608         if (!get_v3_ds_connect) {
 609                 get_v3_ds_connect = symbol_request(nfs3_set_ds_client);
 610                 WARN_ON_ONCE(!get_v3_ds_connect);
 611         }
 612
 613         return(get_v3_ds_connect != NULL);
 614 }
 615
 616 void nfs4_pnfs_v3_ds_connect_unload(void)
 617 {
 618         if (get_v3_ds_connect) {
 619                 symbol_put(nfs3_set_ds_client);
 620                 get_v3_ds_connect = NULL;
 621         }
 622 }
 623 EXPORT_SYMBOL_GPL(nfs4_pnfs_v3_ds_connect_unload);
 624
 625 static int _nfs4_pnfs_v3_ds_connect(struct nfs_server *mds_srv,
 626                                  struct nfs4_pnfs_ds *ds,
 627                                  unsigned int timeo,
 628                                  unsigned int retrans,
 629                                  rpc_authflavor_t au_flavor)
 630 {
 631         struct nfs_client *clp = ERR_PTR(-EIO);
 632         struct nfs4_pnfs_ds_addr *da;
 633         int status = 0;
 634
 635         dprintk("--> %s DS %s au_flavor %d\n", __func__,
 636                 ds->ds_remotestr, au_flavor);
 637
 638         if (!load_v3_ds_connect())
 639                 goto out;
 640
 641         list_for_each_entry(da, &ds->ds_addrs, da_node) {
 642                 dprintk("%s: DS %s: trying address %s\n",
 643                         __func__, ds->ds_remotestr, da->da_remotestr);
 644
 645                 if (!IS_ERR(clp)) {
 646                         struct xprt_create xprt_args = {
 647                                 .ident = XPRT_TRANSPORT_TCP,
 648                                 .net = clp->cl_net,
 649                                 .dstaddr = (struct sockaddr *)&da->da_addr,
 650                                 .addrlen = da->da_addrlen,
 651                                 .servername = clp->cl_hostname,
 652                         };
 653                         /* Add this address as an alias */
 654                         rpc_clnt_add_xprt(clp->cl_rpcclient, &xprt_args,
 655                                         rpc_clnt_test_and_add_xprt, NULL);
 656                 } else
 657                         clp = get_v3_ds_connect(mds_srv,
 658                                         (struct sockaddr *)&da->da_addr,
 659                                         da->da_addrlen, IPPROTO_TCP,
 660                                         timeo, retrans, au_flavor);
 661         }
 662
 663         if (IS_ERR(clp)) {
 664                 status = PTR_ERR(clp);
 665                 goto out;
 666         }
 667
 668         smp_wmb();
 669         ds->ds_clp = clp;
 670         dprintk("%s [new] addr: %s\n", __func__, ds->ds_remotestr);
 671 out:
 672         return status;
 673 }
 674
 675 static int _nfs4_pnfs_v4_ds_connect(struct nfs_server *mds_srv,
 676                                  struct nfs4_pnfs_ds *ds,
 677                                  unsigned int timeo,
 678                                  unsigned int retrans,
 679                                  u32 minor_version,
 680                                  rpc_authflavor_t au_flavor)
 681 {
 682         struct nfs_client *clp = ERR_PTR(-EIO);
 683         struct nfs4_pnfs_ds_addr *da;
 684         int status = 0;
 685
 686         dprintk("--> %s DS %s au_flavor %d\n", __func__, ds->ds_remotestr,
 687                 au_flavor);
 688
 689         list_for_each_entry(da, &ds->ds_addrs, da_node) {
 690                 dprintk("%s: DS %s: trying address %s\n",
 691                         __func__, ds->ds_remotestr, da->da_remotestr);
 692
 693                 if (!IS_ERR(clp) && clp->cl_mvops->session_trunk) {
 694                         struct xprt_create xprt_args = {
 695                                 .ident = XPRT_TRANSPORT_TCP,
 696                                 .net = clp->cl_net,
 697                                 .dstaddr = (struct sockaddr *)&da->da_addr,
 698                                 .addrlen = da->da_addrlen,
 699                                 .servername = clp->cl_hostname,
 700                         };
 701                         struct nfs4_add_xprt_data xprtdata = {
 702                                 .clp = clp,
 703                                 .cred = nfs4_get_clid_cred(clp),
 704                         };
 705                         struct rpc_add_xprt_test rpcdata = {
 706                                 .add_xprt_test = clp->cl_mvops->session_trunk,
 707                                 .data = &xprtdata,
 708                         };
 709
 710                         /**
 711                         * Test this address for session trunking and
 712                         * add as an alias
 713                         */
 714                         rpc_clnt_add_xprt(clp->cl_rpcclient, &xprt_args,
 715                                           rpc_clnt_setup_test_and_add_xprt,
 716                                           &rpcdata);
 717                         if (xprtdata.cred)
 718                                 put_rpccred(xprtdata.cred);
 719                 } else {
 720                         clp = nfs4_set_ds_client(mds_srv,
 721                                                 (struct sockaddr *)&da->da_addr,
 722                                                 da->da_addrlen, IPPROTO_TCP,
 723                                                 timeo, retrans, minor_version,
 724                                                 au_flavor);
 725                         if (IS_ERR(clp))
 726                                 continue;
 727
 728                         status = nfs4_init_ds_session(clp,
 729                                         mds_srv->nfs_client->cl_lease_time);
 730                         if (status) {
 731                                 nfs_put_client(clp);
 732                                 clp = ERR_PTR(-EIO);
 733                                 continue;
 734                         }
 735
 736                 }
 737         }
 738
 739         if (IS_ERR(clp)) {
 740                 status = PTR_ERR(clp);
 741                 goto out;
 742         }
 743
 744         smp_wmb();
 745         ds->ds_clp = clp;
 746         dprintk("%s [new] addr: %s\n", __func__, ds->ds_remotestr);
 747 out:
 748         return status;
 749 }
 750
 751 /*
 752  * Create an rpc connection to the nfs4_pnfs_ds data server.
 753  * Currently only supports IPv4 and IPv6 addresses.
 754  * If connection fails, make devid unavailable.
 755  */
 756 void nfs4_pnfs_ds_connect(struct nfs_server *mds_srv, struct nfs4_pnfs_ds *ds,
 757                           struct nfs4_deviceid_node *devid, unsigned int timeo,
 758                           unsigned int retrans, u32 version,
 759                           u32 minor_version, rpc_authflavor_t au_flavor)
 760 {
 761         if (test_and_set_bit(NFS4DS_CONNECTING, &ds->ds_state) == 0) {
 762                 int err = 0;
 763
 764                 if (version == 3) {
 765                         err = _nfs4_pnfs_v3_ds_connect(mds_srv, ds, timeo,
 766                                                        retrans, au_flavor);
 767                 } else if (version == 4) {
 768                         err = _nfs4_pnfs_v4_ds_connect(mds_srv, ds, timeo,
 769                                                        retrans, minor_version,
 770                                                        au_flavor);
 771                 } else {
 772                         dprintk("%s: unsupported DS version %d\n", __func__,
 773                                 version);
 774                         err = -EPROTONOSUPPORT;
 775                 }
 776
 777                 if (err)
 778                         nfs4_mark_deviceid_unavailable(devid);
 779                 nfs4_clear_ds_conn_bit(ds);
 780         } else {
 781                 nfs4_wait_ds_connect(ds);
 782         }
 783 }
 784 EXPORT_SYMBOL_GPL(nfs4_pnfs_ds_connect);
 785
 786 /*
 787  * Currently only supports ipv4, ipv6 and one multi-path address.
 788  */
 789 struct nfs4_pnfs_ds_addr *
 790 nfs4_decode_mp_ds_addr(struct net *net, struct xdr_stream *xdr, gfp_t gfp_flags)
 791 {
 792         struct nfs4_pnfs_ds_addr *da = NULL;
 793         char *buf, *portstr;
 794         __be16 port;
 795         int nlen, rlen;
 796         int tmp[2];
 797         __be32 *p;
 798         char *netid, *match_netid;
 799         size_t len, match_netid_len;
 800         char *startsep = "";
 801         char *endsep = "";
 802
 803
 804         /* r_netid */
 805         p = xdr_inline_decode(xdr, 4);
 806         if (unlikely(!p))
 807                 goto out_err;
 808         nlen = be32_to_cpup(p++);
 809
 810         p = xdr_inline_decode(xdr, nlen);
 811         if (unlikely(!p))
 812                 goto out_err;
 813
 814         netid = kmalloc(nlen+1, gfp_flags);
 815         if (unlikely(!netid))
 816                 goto out_err;
 817
 818         netid[nlen] = '\0';
 819         memcpy(netid, p, nlen);
 820
 821         /* r_addr: ip/ip6addr with port in dec octets - see RFC 5665 */
 822         p = xdr_inline_decode(xdr, 4);
 823         if (unlikely(!p))
 824                 goto out_free_netid;
 825         rlen = be32_to_cpup(p);
 826
 827         p = xdr_inline_decode(xdr, rlen);
 828         if (unlikely(!p))
 829                 goto out_free_netid;
 830
 831         /* port is ".ABC.DEF", 8 chars max */
 832         if (rlen > INET6_ADDRSTRLEN + IPV6_SCOPE_ID_LEN + 8) {
 833                 dprintk("%s: Invalid address, length %d\n", __func__,
 834                         rlen);
 835                 goto out_free_netid;
 836         }
 837         buf = kmalloc(rlen + 1, gfp_flags);
 838         if (!buf) {
 839                 dprintk("%s: Not enough memory\n", __func__);
 840                 goto out_free_netid;
 841         }
 842         buf[rlen] = '\0';
 843         memcpy(buf, p, rlen);
 844
 845         /* replace port '.' with '-' */
 846         portstr = strrchr(buf, '.');
 847         if (!portstr) {
 848                 dprintk("%s: Failed finding expected dot in port\n",
 849                         __func__);
 850                 goto out_free_buf;
 851         }
 852         *portstr = '-';
 853
 854         /* find '.' between address and port */
 855         portstr = strrchr(buf, '.');
 856         if (!portstr) {
 857                 dprintk("%s: Failed finding expected dot between address and "
 858                         "port\n", __func__);
 859                 goto out_free_buf;
 860         }
 861         *portstr = '\0';
 862
 863         da = kzalloc(sizeof(*da), gfp_flags);
 864         if (unlikely(!da))
 865                 goto out_free_buf;
 866
 867         INIT_LIST_HEAD(&da->da_node);
 868
 869         if (!rpc_pton(net, buf, portstr-buf, (struct sockaddr *)&da->da_addr,
 870                       sizeof(da->da_addr))) {
 871                 dprintk("%s: error parsing address %s\n", __func__, buf);
 872                 goto out_free_da;
 873         }
 874
 875         portstr++;
 876         sscanf(portstr, "%d-%d", &tmp[0], &tmp[1]);
 877         port = htons((tmp[0] << 8) | (tmp[1]));
 878
 879         switch (da->da_addr.ss_family) {
 880         case AF_INET:
 881                 ((struct sockaddr_in *)&da->da_addr)->sin_port = port;
 882                 da->da_addrlen = sizeof(struct sockaddr_in);
 883                 match_netid = "tcp";
 884                 match_netid_len = 3;
 885                 break;
 886
 887         case AF_INET6:
 888                 ((struct sockaddr_in6 *)&da->da_addr)->sin6_port = port;
 889                 da->da_addrlen = sizeof(struct sockaddr_in6);
 890                 match_netid = "tcp6";
 891                 match_netid_len = 4;
 892                 startsep = "[";
 893                 endsep = "]";
 894                 break;
 895
 896         default:
 897                 dprintk("%s: unsupported address family: %u\n",
 898                         __func__, da->da_addr.ss_family);
 899                 goto out_free_da;
 900         }
 901
 902         if (nlen != match_netid_len || strncmp(netid, match_netid, nlen)) {
 903                 dprintk("%s: ERROR: r_netid \"%s\" != \"%s\"\n",
 904                         __func__, netid, match_netid);
 905                 goto out_free_da;
 906         }
 907
 908         /* save human readable address */
 909         len = strlen(startsep) + strlen(buf) + strlen(endsep) + 7;
 910         da->da_remotestr = kzalloc(len, gfp_flags);
 911
 912         /* NULL is ok, only used for dprintk */
 913         if (da->da_remotestr)
 914                 snprintf(da->da_remotestr, len, "%s%s%s:%u", startsep,
 915                          buf, endsep, ntohs(port));
 916
 917         dprintk("%s: Parsed DS addr %s\n", __func__, da->da_remotestr);
 918         kfree(buf);
 919         kfree(netid);
 920         return da;
 921
 922 out_free_da:
 923         kfree(da);
 924 out_free_buf:
 925         dprintk("%s: Error parsing DS addr: %s\n", __func__, buf);
 926         kfree(buf);
 927 out_free_netid:
 928         kfree(netid);
 929 out_err:
 930         return NULL;
 931 }
 932 EXPORT_SYMBOL_GPL(nfs4_decode_mp_ds_addr);
 933
 934 void
 935 pnfs_layout_mark_request_commit(struct nfs_page *req,
 936                                 struct pnfs_layout_segment *lseg,
 937                                 struct nfs_commit_info *cinfo,
 938                                 u32 ds_commit_idx)
 939 {
 940         struct list_head *list;
 941         struct pnfs_commit_bucket *buckets;
 942
 943         spin_lock(&cinfo->inode->i_lock);
 944         buckets = cinfo->ds->buckets;
 945         list = &buckets[ds_commit_idx].written;
 946         if (list_empty(list)) {
 947                 if (!pnfs_is_valid_lseg(lseg)) {
 948                         spin_unlock(&cinfo->inode->i_lock);
 949                         cinfo->completion_ops->resched_write(cinfo, req);
 950                         return;
 951                 }
 952                 /* Non-empty buckets hold a reference on the lseg.  That ref
 953                  * is normally transferred to the COMMIT call and released
 954                  * there.  It could also be released if the last req is pulled
 955                  * off due to a rewrite, in which case it will be done in
 956                  * pnfs_common_clear_request_commit
 957                  */
 958                 WARN_ON_ONCE(buckets[ds_commit_idx].wlseg != NULL);
 959                 buckets[ds_commit_idx].wlseg = pnfs_get_lseg(lseg);
 960         }
 961         set_bit(PG_COMMIT_TO_DS, &req->wb_flags);
 962         cinfo->ds->nwritten++;
 963
 964         nfs_request_add_commit_list_locked(req, list, cinfo);
 965         spin_unlock(&cinfo->inode->i_lock);
 966         nfs_mark_page_unstable(req->wb_page, cinfo);
 967 }
 968 EXPORT_SYMBOL_GPL(pnfs_layout_mark_request_commit);
 969
 970 int
 971 pnfs_nfs_generic_sync(struct inode *inode, bool datasync)
 972 {
 973         int ret;
 974
 975         if (!pnfs_layoutcommit_outstanding(inode))
 976                 return 0;
 977         ret = nfs_commit_inode(inode, FLUSH_SYNC);
 978         if (ret < 0)
 979                 return ret;
 980         if (datasync)
 981                 return 0;
 982         return pnfs_layoutcommit_inode(inode, true);
 983 }
 984 EXPORT_SYMBOL_GPL(pnfs_nfs_generic_sync);
 985