fs/nfs/nfs4filelayoutdev.c

   1 /*
   2  *  Device operations for the pnfs nfs4 file layout driver.
   3  *
   4  *  Copyright (c) 2002
   5  *  The Regents of the University of Michigan
   6  *  All Rights Reserved
   7  *
   8  *  Dean Hildebrand <dhildebz@umich.edu>
   9  *  Garth Goodson   <Garth.Goodson@netapp.com>
  10  *
  11  *  Permission is granted to use, copy, create derivative works, and
  12  *  redistribute this software and such derivative works for any purpose,
  13  *  so long as the name of the University of Michigan is not used in
  14  *  any advertising or publicity pertaining to the use or distribution
  15  *  of this software without specific, written prior authorization. If
  16  *  the above copyright notice or any other identification of the
  17  *  University of Michigan is included in any copy of any portion of
  18  *  this software, then the disclaimer below must also be included.
  19  *
  20  *  This software is provided as is, without representation or warranty
  21  *  of any kind either express or implied, including without limitation
  22  *  the implied warranties of merchantability, fitness for a particular
  23  *  purpose, or noninfringement.  The Regents of the University of
  24  *  Michigan shall not be liable for any damages, including special,
  25  *  indirect, incidental, or consequential damages, with respect to any
  26  *  claim arising out of or in connection with the use of the software,
  27  *  even if it has been or is hereafter advised of the possibility of
  28  *  such damages.
  29  */
  30
  31 #include <linux/nfs_fs.h>
  32 #include <linux/vmalloc.h>
  33
  34 #include "internal.h"
  35 #include "nfs4filelayout.h"
  36
  37 #define NFSDBG_FACILITY         NFSDBG_PNFS_LD
  38
  39 /*
  40  * Data server cache
  41  *
  42  * Data servers can be mapped to different device ids.
  43  * nfs4_pnfs_ds reference counting
  44  *   - set to 1 on allocation
  45  *   - incremented when a device id maps a data server already in the cache.
  46  *   - decremented when deviceid is removed from the cache.
  47  */
  48 DEFINE_SPINLOCK(nfs4_ds_cache_lock);
  49 static LIST_HEAD(nfs4_data_server_cache);
  50
  51 /* Debug routines */
  52 void
  53 print_ds(struct nfs4_pnfs_ds *ds)
  54 {
  55         if (ds == NULL) {
  56                 printk("%s NULL device\n", __func__);
  57                 return;
  58         }
  59         printk("        ds %s\n"
  60                 "        ref count %d\n"
  61                 "        client %p\n"
  62                 "        cl_exchange_flags %x\n",
  63                 ds->ds_remotestr,
  64                 atomic_read(&ds->ds_count), ds->ds_clp,
  65                 ds->ds_clp ? ds->ds_clp->cl_exchange_flags : 0);
  66 }
  67
  68 static bool
  69 same_sockaddr(struct sockaddr *addr1, struct sockaddr *addr2)
  70 {
  71         struct sockaddr_in *a, *b;
  72         struct sockaddr_in6 *a6, *b6;
  73
  74         if (addr1->sa_family != addr2->sa_family)
  75                 return false;
  76
  77         switch (addr1->sa_family) {
  78         case AF_INET:
  79                 a = (struct sockaddr_in *)addr1;
  80                 b = (struct sockaddr_in *)addr2;
  81
  82                 if (a->sin_addr.s_addr == b->sin_addr.s_addr &&
  83                     a->sin_port == b->sin_port)
  84                         return true;
  85                 break;
  86
  87         case AF_INET6:
  88                 a6 = (struct sockaddr_in6 *)addr1;
  89                 b6 = (struct sockaddr_in6 *)addr2;
  90
  91                 /* LINKLOCAL addresses must have matching scope_id */
  92                 if (ipv6_addr_scope(&a6->sin6_addr) ==
  93                     IPV6_ADDR_SCOPE_LINKLOCAL &&
  94                     a6->sin6_scope_id != b6->sin6_scope_id)
  95                         return false;
  96
  97                 if (ipv6_addr_equal(&a6->sin6_addr, &b6->sin6_addr) &&
  98                     a6->sin6_port == b6->sin6_port)
  99                         return true;
 100                 break;
 101
 102         default:
 103                 dprintk("%s: unhandled address family: %u\n",
 104                         __func__, addr1->sa_family);
 105                 return false;
 106         }
 107
 108         return false;
 109 }
 110
 111 /*
 112  * Lookup DS by addresses.  The first matching address returns true.
 113  * nfs4_ds_cache_lock is held
 114  */
 115 static struct nfs4_pnfs_ds *
 116 _data_server_lookup_locked(struct list_head *dsaddrs)
 117 {
 118         struct nfs4_pnfs_ds *ds;
 119         struct nfs4_pnfs_ds_addr *da1, *da2;
 120
 121         list_for_each_entry(da1, dsaddrs, da_node) {
 122                 list_for_each_entry(ds, &nfs4_data_server_cache, ds_node) {
 123                         list_for_each_entry(da2, &ds->ds_addrs, da_node) {
 124                                 if (same_sockaddr(
 125                                         (struct sockaddr *)&da1->da_addr,
 126                                         (struct sockaddr *)&da2->da_addr))
 127                                         return ds;
 128                         }
 129                 }
 130         }
 131         return NULL;
 132 }
 133
 134 /*
 135  * Compare two lists of addresses.
 136  */
 137 static bool
 138 _data_server_match_all_addrs_locked(struct list_head *dsaddrs1,
 139                                     struct list_head *dsaddrs2)
 140 {
 141         struct nfs4_pnfs_ds_addr *da1, *da2;
 142         size_t count1 = 0,
 143                count2 = 0;
 144
 145         list_for_each_entry(da1, dsaddrs1, da_node)
 146                 count1++;
 147
 148         list_for_each_entry(da2, dsaddrs2, da_node) {
 149                 bool found = false;
 150                 count2++;
 151                 list_for_each_entry(da1, dsaddrs1, da_node) {
 152                         if (same_sockaddr((struct sockaddr *)&da1->da_addr,
 153                                 (struct sockaddr *)&da2->da_addr)) {
 154                                 found = true;
 155                                 break;
 156                         }
 157                 }
 158                 if (!found)
 159                         return false;
 160         }
 161
 162         return (count1 == count2);
 163 }
 164
 165 /*
 166  * Create an rpc connection to the nfs4_pnfs_ds data server
 167  * Currently only supports IPv4 and IPv6 addresses
 168  */
 169 static int
 170 nfs4_ds_connect(struct nfs_server *mds_srv, struct nfs4_pnfs_ds *ds)
 171 {
 172         struct nfs_client *clp = ERR_PTR(-EIO);
 173         struct nfs4_pnfs_ds_addr *da;
 174         int status = 0;
 175
 176         dprintk("--> %s DS %s au_flavor %d\n", __func__, ds->ds_remotestr,
 177                 mds_srv->nfs_client->cl_rpcclient->cl_auth->au_flavor);
 178
 179         BUG_ON(list_empty(&ds->ds_addrs));
 180
 181         list_for_each_entry(da, &ds->ds_addrs, da_node) {
 182                 dprintk("%s: DS %s: trying address %s\n",
 183                         __func__, ds->ds_remotestr, da->da_remotestr);
 184
 185                 clp = nfs4_set_ds_client(mds_srv->nfs_client,
 186                                  (struct sockaddr *)&da->da_addr,
 187                                  da->da_addrlen, IPPROTO_TCP);
 188                 if (!IS_ERR(clp))
 189                         break;
 190         }
 191
 192         if (IS_ERR(clp)) {
 193                 status = PTR_ERR(clp);
 194                 goto out;
 195         }
 196
 197         if ((clp->cl_exchange_flags & EXCHGID4_FLAG_MASK_PNFS) != 0) {
 198                 if (!is_ds_client(clp)) {
 199                         status = -ENODEV;
 200                         goto out_put;
 201                 }
 202                 ds->ds_clp = clp;
 203                 dprintk("%s [existing] server=%s\n", __func__,
 204                         ds->ds_remotestr);
 205                 goto out;
 206         }
 207
 208         /*
 209          * Do not set NFS_CS_CHECK_LEASE_TIME instead set the DS lease to
 210          * be equal to the MDS lease. Renewal is scheduled in create_session.
 211          */
 212         spin_lock(&mds_srv->nfs_client->cl_lock);
 213         clp->cl_lease_time = mds_srv->nfs_client->cl_lease_time;
 214         spin_unlock(&mds_srv->nfs_client->cl_lock);
 215         clp->cl_last_renewal = jiffies;
 216
 217         /* New nfs_client */
 218         status = nfs4_init_ds_session(clp);
 219         if (status)
 220                 goto out_put;
 221
 222         ds->ds_clp = clp;
 223         dprintk("%s [new] addr: %s\n", __func__, ds->ds_remotestr);
 224 out:
 225         return status;
 226 out_put:
 227         nfs_put_client(clp);
 228         goto out;
 229 }
 230
 231 static void
 232 destroy_ds(struct nfs4_pnfs_ds *ds)
 233 {
 234         struct nfs4_pnfs_ds_addr *da;
 235
 236         dprintk("--> %s\n", __func__);
 237         ifdebug(FACILITY)
 238                 print_ds(ds);
 239
 240         if (ds->ds_clp)
 241                 nfs_put_client(ds->ds_clp);
 242
 243         while (!list_empty(&ds->ds_addrs)) {
 244                 da = list_first_entry(&ds->ds_addrs,
 245                                       struct nfs4_pnfs_ds_addr,
 246                                       da_node);
 247                 list_del_init(&da->da_node);
 248                 kfree(da->da_remotestr);
 249                 kfree(da);
 250         }
 251
 252         kfree(ds->ds_remotestr);
 253         kfree(ds);
 254 }
 255
 256 void
 257 nfs4_fl_free_deviceid(struct nfs4_file_layout_dsaddr *dsaddr)
 258 {
 259         struct nfs4_pnfs_ds *ds;
 260         int i;
 261
 262         nfs4_print_deviceid(&dsaddr->id_node.deviceid);
 263
 264         for (i = 0; i < dsaddr->ds_num; i++) {
 265                 ds = dsaddr->ds_list[i];
 266                 if (ds != NULL) {
 267                         if (atomic_dec_and_lock(&ds->ds_count,
 268                                                 &nfs4_ds_cache_lock)) {
 269                                 list_del_init(&ds->ds_node);
 270                                 spin_unlock(&nfs4_ds_cache_lock);
 271                                 destroy_ds(ds);
 272                         }
 273                 }
 274         }
 275         kfree(dsaddr->stripe_indices);
 276         kfree(dsaddr);
 277 }
 278
 279 /*
 280  * Create a string with a human readable address and port to avoid
 281  * complicated setup around many dprinks.
 282  */
 283 static char *
 284 nfs4_pnfs_remotestr(struct list_head *dsaddrs, gfp_t gfp_flags)
 285 {
 286         struct nfs4_pnfs_ds_addr *da;
 287         char *remotestr;
 288         size_t len;
 289         char *p;
 290
 291         len = 3;        /* '{', '}' and eol */
 292         list_for_each_entry(da, dsaddrs, da_node) {
 293                 len += strlen(da->da_remotestr) + 1;    /* string plus comma */
 294         }
 295
 296         remotestr = kzalloc(len, gfp_flags);
 297         if (!remotestr)
 298                 return NULL;
 299
 300         p = remotestr;
 301         *(p++) = '{';
 302         len--;
 303         list_for_each_entry(da, dsaddrs, da_node) {
 304                 size_t ll = strlen(da->da_remotestr);
 305
 306                 if (ll > len)
 307                         goto out_err;
 308
 309                 memcpy(p, da->da_remotestr, ll);
 310                 p += ll;
 311                 len -= ll;
 312
 313                 if (len < 1)
 314                         goto out_err;
 315                 (*p++) = ',';
 316                 len--;
 317         }
 318         if (len < 2)
 319                 goto out_err;
 320         *(p++) = '}';
 321         *p = '\0';
 322         return remotestr;
 323 out_err:
 324         kfree(remotestr);
 325         return NULL;
 326 }
 327
 328 static struct nfs4_pnfs_ds *
 329 nfs4_pnfs_ds_add(struct list_head *dsaddrs, gfp_t gfp_flags)
 330 {
 331         struct nfs4_pnfs_ds *tmp_ds, *ds = NULL;
 332         char *remotestr;
 333
 334         if (list_empty(dsaddrs)) {
 335                 dprintk("%s: no addresses defined\n", __func__);
 336                 goto out;
 337         }
 338
 339         ds = kzalloc(sizeof(*ds), gfp_flags);
 340         if (!ds)
 341                 goto out;
 342
 343         /* this is only used for debugging, so it's ok if its NULL */
 344         remotestr = nfs4_pnfs_remotestr(dsaddrs, gfp_flags);
 345
 346         spin_lock(&nfs4_ds_cache_lock);
 347         tmp_ds = _data_server_lookup_locked(dsaddrs);
 348         if (tmp_ds == NULL) {
 349                 INIT_LIST_HEAD(&ds->ds_addrs);
 350                 list_splice_init(dsaddrs, &ds->ds_addrs);
 351                 ds->ds_remotestr = remotestr;
 352                 atomic_set(&ds->ds_count, 1);
 353                 INIT_LIST_HEAD(&ds->ds_node);
 354                 ds->ds_clp = NULL;
 355                 list_add(&ds->ds_node, &nfs4_data_server_cache);
 356                 dprintk("%s add new data server %s\n", __func__,
 357                         ds->ds_remotestr);
 358         } else {
 359                 if (!_data_server_match_all_addrs_locked(&tmp_ds->ds_addrs,
 360                                                          dsaddrs)) {
 361                         dprintk("%s:  multipath address mismatch: %s != %s",
 362                                 __func__, tmp_ds->ds_remotestr, remotestr);
 363                 }
 364                 kfree(remotestr);
 365                 kfree(ds);
 366                 atomic_inc(&tmp_ds->ds_count);
 367                 dprintk("%s data server %s found, inc'ed ds_count to %d\n",
 368                         __func__, tmp_ds->ds_remotestr,
 369                         atomic_read(&tmp_ds->ds_count));
 370                 ds = tmp_ds;
 371         }
 372         spin_unlock(&nfs4_ds_cache_lock);
 373 out:
 374         return ds;
 375 }
 376
 377 /*
 378  * Currently only supports ipv4, ipv6 and one multi-path address.
 379  */
 380 static struct nfs4_pnfs_ds_addr *
 381 decode_ds_addr(struct xdr_stream *streamp, gfp_t gfp_flags)
 382 {
 383         struct nfs4_pnfs_ds_addr *da = NULL;
 384         char *buf, *portstr;
 385         u32 port;
 386         int nlen, rlen;
 387         int tmp[2];
 388         __be32 *p;
 389         char *netid, *match_netid;
 390         size_t len, match_netid_len;
 391         char *startsep = "";
 392         char *endsep = "";
 393
 394
 395         /* r_netid */
 396         p = xdr_inline_decode(streamp, 4);
 397         if (unlikely(!p))
 398                 goto out_err;
 399         nlen = be32_to_cpup(p++);
 400
 401         p = xdr_inline_decode(streamp, nlen);
 402         if (unlikely(!p))
 403                 goto out_err;
 404
 405         netid = kmalloc(nlen+1, gfp_flags);
 406         if (unlikely(!netid))
 407                 goto out_err;
 408
 409         netid[nlen] = '\0';
 410         memcpy(netid, p, nlen);
 411
 412         /* r_addr: ip/ip6addr with port in dec octets - see RFC 5665 */
 413         p = xdr_inline_decode(streamp, 4);
 414         if (unlikely(!p))
 415                 goto out_free_netid;
 416         rlen = be32_to_cpup(p);
 417
 418         p = xdr_inline_decode(streamp, rlen);
 419         if (unlikely(!p))
 420                 goto out_free_netid;
 421
 422         /* port is ".ABC.DEF", 8 chars max */
 423         if (rlen > INET6_ADDRSTRLEN + IPV6_SCOPE_ID_LEN + 8) {
 424                 dprintk("%s: Invalid address, length %d\n", __func__,
 425                         rlen);
 426                 goto out_free_netid;
 427         }
 428         buf = kmalloc(rlen + 1, gfp_flags);
 429         if (!buf) {
 430                 dprintk("%s: Not enough memory\n", __func__);
 431                 goto out_free_netid;
 432         }
 433         buf[rlen] = '\0';
 434         memcpy(buf, p, rlen);
 435
 436         /* replace port '.' with '-' */
 437         portstr = strrchr(buf, '.');
 438         if (!portstr) {
 439                 dprintk("%s: Failed finding expected dot in port\n",
 440                         __func__);
 441                 goto out_free_buf;
 442         }
 443         *portstr = '-';
 444
 445         /* find '.' between address and port */
 446         portstr = strrchr(buf, '.');
 447         if (!portstr) {
 448                 dprintk("%s: Failed finding expected dot between address and "
 449                         "port\n", __func__);
 450                 goto out_free_buf;
 451         }
 452         *portstr = '\0';
 453
 454         da = kzalloc(sizeof(*da), gfp_flags);
 455         if (unlikely(!da))
 456                 goto out_free_buf;
 457
 458         INIT_LIST_HEAD(&da->da_node);
 459
 460         if (!rpc_pton(buf, portstr-buf, (struct sockaddr *)&da->da_addr,
 461                       sizeof(da->da_addr))) {
 462                 dprintk("%s: error parsing address %s\n", __func__, buf);
 463                 goto out_free_da;
 464         }
 465
 466         portstr++;
 467         sscanf(portstr, "%d-%d", &tmp[0], &tmp[1]);
 468         port = htons((tmp[0] << 8) | (tmp[1]));
 469
 470         switch (da->da_addr.ss_family) {
 471         case AF_INET:
 472                 ((struct sockaddr_in *)&da->da_addr)->sin_port = port;
 473                 da->da_addrlen = sizeof(struct sockaddr_in);
 474                 match_netid = "tcp";
 475                 match_netid_len = 3;
 476                 break;
 477
 478         case AF_INET6:
 479                 ((struct sockaddr_in6 *)&da->da_addr)->sin6_port = port;
 480                 da->da_addrlen = sizeof(struct sockaddr_in6);
 481                 match_netid = "tcp6";
 482                 match_netid_len = 4;
 483                 startsep = "[";
 484                 endsep = "]";
 485                 break;
 486
 487         default:
 488                 dprintk("%s: unsupported address family: %u\n",
 489                         __func__, da->da_addr.ss_family);
 490                 goto out_free_da;
 491         }
 492
 493         if (nlen != match_netid_len || strncmp(netid, match_netid, nlen)) {
 494                 dprintk("%s: ERROR: r_netid \"%s\" != \"%s\"\n",
 495                         __func__, netid, match_netid);
 496                 goto out_free_da;
 497         }
 498
 499         /* save human readable address */
 500         len = strlen(startsep) + strlen(buf) + strlen(endsep) + 7;
 501         da->da_remotestr = kzalloc(len, gfp_flags);
 502
 503         /* NULL is ok, only used for dprintk */
 504         if (da->da_remotestr)
 505                 snprintf(da->da_remotestr, len, "%s%s%s:%u", startsep,
 506                          buf, endsep, ntohs(port));
 507
 508         dprintk("%s: Parsed DS addr %s\n", __func__, da->da_remotestr);
 509         kfree(buf);
 510         kfree(netid);
 511         return da;
 512
 513 out_free_da:
 514         kfree(da);
 515 out_free_buf:
 516         dprintk("%s: Error parsing DS addr: %s\n", __func__, buf);
 517         kfree(buf);
 518 out_free_netid:
 519         kfree(netid);
 520 out_err:
 521         return NULL;
 522 }
 523
 524 /* Decode opaque device data and return the result */
 525 static struct nfs4_file_layout_dsaddr*
 526 decode_device(struct inode *ino, struct pnfs_device *pdev, gfp_t gfp_flags)
 527 {
 528         int i;
 529         u32 cnt, num;
 530         u8 *indexp;
 531         __be32 *p;
 532         u8 *stripe_indices;
 533         u8 max_stripe_index;
 534         struct nfs4_file_layout_dsaddr *dsaddr = NULL;
 535         struct xdr_stream stream;
 536         struct xdr_buf buf;
 537         struct page *scratch;
 538         struct list_head dsaddrs;
 539         struct nfs4_pnfs_ds_addr *da;
 540
 541         /* set up xdr stream */
 542         scratch = alloc_page(gfp_flags);
 543         if (!scratch)
 544                 goto out_err;
 545
 546         xdr_init_decode_pages(&stream, &buf, pdev->pages, pdev->pglen);
 547         xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
 548
 549         /* Get the stripe count (number of stripe index) */
 550         p = xdr_inline_decode(&stream, 4);
 551         if (unlikely(!p))
 552                 goto out_err_free_scratch;
 553
 554         cnt = be32_to_cpup(p);
 555         dprintk("%s stripe count  %d\n", __func__, cnt);
 556         if (cnt > NFS4_PNFS_MAX_STRIPE_CNT) {
 557                 printk(KERN_WARNING "%s: stripe count %d greater than "
 558                        "supported maximum %d\n", __func__,
 559                         cnt, NFS4_PNFS_MAX_STRIPE_CNT);
 560                 goto out_err_free_scratch;
 561         }
 562
 563         /* read stripe indices */
 564         stripe_indices = kcalloc(cnt, sizeof(u8), gfp_flags);
 565         if (!stripe_indices)
 566                 goto out_err_free_scratch;
 567
 568         p = xdr_inline_decode(&stream, cnt << 2);
 569         if (unlikely(!p))
 570                 goto out_err_free_stripe_indices;
 571
 572         indexp = &stripe_indices[0];
 573         max_stripe_index = 0;
 574         for (i = 0; i < cnt; i++) {
 575                 *indexp = be32_to_cpup(p++);
 576                 max_stripe_index = max(max_stripe_index, *indexp);
 577                 indexp++;
 578         }
 579
 580         /* Check the multipath list count */
 581         p = xdr_inline_decode(&stream, 4);
 582         if (unlikely(!p))
 583                 goto out_err_free_stripe_indices;
 584
 585         num = be32_to_cpup(p);
 586         dprintk("%s ds_num %u\n", __func__, num);
 587         if (num > NFS4_PNFS_MAX_MULTI_CNT) {
 588                 printk(KERN_WARNING "%s: multipath count %d greater than "
 589                         "supported maximum %d\n", __func__,
 590                         num, NFS4_PNFS_MAX_MULTI_CNT);
 591                 goto out_err_free_stripe_indices;
 592         }
 593
 594         /* validate stripe indices are all < num */
 595         if (max_stripe_index >= num) {
 596                 printk(KERN_WARNING "%s: stripe index %u >= num ds %u\n",
 597                         __func__, max_stripe_index, num);
 598                 goto out_err_free_stripe_indices;
 599         }
 600
 601         dsaddr = kzalloc(sizeof(*dsaddr) +
 602                         (sizeof(struct nfs4_pnfs_ds *) * (num - 1)),
 603                         gfp_flags);
 604         if (!dsaddr)
 605                 goto out_err_free_stripe_indices;
 606
 607         dsaddr->stripe_count = cnt;
 608         dsaddr->stripe_indices = stripe_indices;
 609         stripe_indices = NULL;
 610         dsaddr->ds_num = num;
 611         nfs4_init_deviceid_node(&dsaddr->id_node,
 612                                 NFS_SERVER(ino)->pnfs_curr_ld,
 613                                 NFS_SERVER(ino)->nfs_client,
 614                                 &pdev->dev_id);
 615
 616         INIT_LIST_HEAD(&dsaddrs);
 617
 618         for (i = 0; i < dsaddr->ds_num; i++) {
 619                 int j;
 620                 u32 mp_count;
 621
 622                 p = xdr_inline_decode(&stream, 4);
 623                 if (unlikely(!p))
 624                         goto out_err_free_deviceid;
 625
 626                 mp_count = be32_to_cpup(p); /* multipath count */
 627                 for (j = 0; j < mp_count; j++) {
 628                         da = decode_ds_addr(&stream, gfp_flags);
 629                         if (da)
 630                                 list_add_tail(&da->da_node, &dsaddrs);
 631                 }
 632                 if (list_empty(&dsaddrs)) {
 633                         dprintk("%s: no suitable DS addresses found\n",
 634                                 __func__);
 635                         goto out_err_free_deviceid;
 636                 }
 637
 638                 dsaddr->ds_list[i] = nfs4_pnfs_ds_add(&dsaddrs, gfp_flags);
 639                 if (!dsaddr->ds_list[i])
 640                         goto out_err_drain_dsaddrs;
 641
 642                 /* If DS was already in cache, free ds addrs */
 643                 while (!list_empty(&dsaddrs)) {
 644                         da = list_first_entry(&dsaddrs,
 645                                               struct nfs4_pnfs_ds_addr,
 646                                               da_node);
 647                         list_del_init(&da->da_node);
 648                         kfree(da->da_remotestr);
 649                         kfree(da);
 650                 }
 651         }
 652
 653         __free_page(scratch);
 654         return dsaddr;
 655
 656 out_err_drain_dsaddrs:
 657         while (!list_empty(&dsaddrs)) {
 658                 da = list_first_entry(&dsaddrs, struct nfs4_pnfs_ds_addr,
 659                                       da_node);
 660                 list_del_init(&da->da_node);
 661                 kfree(da->da_remotestr);
 662                 kfree(da);
 663         }
 664 out_err_free_deviceid:
 665         nfs4_fl_free_deviceid(dsaddr);
 666         /* stripe_indicies was part of dsaddr */
 667         goto out_err_free_scratch;
 668 out_err_free_stripe_indices:
 669         kfree(stripe_indices);
 670 out_err_free_scratch:
 671         __free_page(scratch);
 672 out_err:
 673         dprintk("%s ERROR: returning NULL\n", __func__);
 674         return NULL;
 675 }
 676
 677 /*
 678  * Decode the opaque device specified in 'dev' and add it to the cache of
 679  * available devices.
 680  */
 681 static struct nfs4_file_layout_dsaddr *
 682 decode_and_add_device(struct inode *inode, struct pnfs_device *dev, gfp_t gfp_flags)
 683 {
 684         struct nfs4_deviceid_node *d;
 685         struct nfs4_file_layout_dsaddr *n, *new;
 686
 687         new = decode_device(inode, dev, gfp_flags);
 688         if (!new) {
 689                 printk(KERN_WARNING "%s: Could not decode or add device\n",
 690                         __func__);
 691                 return NULL;
 692         }
 693
 694         d = nfs4_insert_deviceid_node(&new->id_node);
 695         n = container_of(d, struct nfs4_file_layout_dsaddr, id_node);
 696         if (n != new) {
 697                 nfs4_fl_free_deviceid(new);
 698                 return n;
 699         }
 700
 701         return new;
 702 }
 703
 704 /*
 705  * Retrieve the information for dev_id, add it to the list
 706  * of available devices, and return it.
 707  */
 708 struct nfs4_file_layout_dsaddr *
 709 get_device_info(struct inode *inode, struct nfs4_deviceid *dev_id, gfp_t gfp_flags)
 710 {
 711         struct pnfs_device *pdev = NULL;
 712         u32 max_resp_sz;
 713         int max_pages;
 714         struct page **pages = NULL;
 715         struct nfs4_file_layout_dsaddr *dsaddr = NULL;
 716         int rc, i;
 717         struct nfs_server *server = NFS_SERVER(inode);
 718
 719         /*
 720          * Use the session max response size as the basis for setting
 721          * GETDEVICEINFO's maxcount
 722          */
 723         max_resp_sz = server->nfs_client->cl_session->fc_attrs.max_resp_sz;
 724         max_pages = max_resp_sz >> PAGE_SHIFT;
 725         dprintk("%s inode %p max_resp_sz %u max_pages %d\n",
 726                 __func__, inode, max_resp_sz, max_pages);
 727
 728         pdev = kzalloc(sizeof(struct pnfs_device), gfp_flags);
 729         if (pdev == NULL)
 730                 return NULL;
 731
 732         pages = kzalloc(max_pages * sizeof(struct page *), gfp_flags);
 733         if (pages == NULL) {
 734                 kfree(pdev);
 735                 return NULL;
 736         }
 737         for (i = 0; i < max_pages; i++) {
 738                 pages[i] = alloc_page(gfp_flags);
 739                 if (!pages[i])
 740                         goto out_free;
 741         }
 742
 743         memcpy(&pdev->dev_id, dev_id, sizeof(*dev_id));
 744         pdev->layout_type = LAYOUT_NFSV4_1_FILES;
 745         pdev->pages = pages;
 746         pdev->pgbase = 0;
 747         pdev->pglen = PAGE_SIZE * max_pages;
 748         pdev->mincount = 0;
 749
 750         rc = nfs4_proc_getdeviceinfo(server, pdev);
 751         dprintk("%s getdevice info returns %d\n", __func__, rc);
 752         if (rc)
 753                 goto out_free;
 754
 755         /*
 756          * Found new device, need to decode it and then add it to the
 757          * list of known devices for this mountpoint.
 758          */
 759         dsaddr = decode_and_add_device(inode, pdev, gfp_flags);
 760 out_free:
 761         for (i = 0; i < max_pages; i++)
 762                 __free_page(pages[i]);
 763         kfree(pages);
 764         kfree(pdev);
 765         dprintk("<-- %s dsaddr %p\n", __func__, dsaddr);
 766         return dsaddr;
 767 }
 768
 769 void
 770 nfs4_fl_put_deviceid(struct nfs4_file_layout_dsaddr *dsaddr)
 771 {
 772         nfs4_put_deviceid_node(&dsaddr->id_node);
 773 }
 774
 775 /*
 776  * Want res = (offset - layout->pattern_offset)/ layout->stripe_unit
 777  * Then: ((res + fsi) % dsaddr->stripe_count)
 778  */
 779 u32
 780 nfs4_fl_calc_j_index(struct pnfs_layout_segment *lseg, loff_t offset)
 781 {
 782         struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
 783         u64 tmp;
 784
 785         tmp = offset - flseg->pattern_offset;
 786         do_div(tmp, flseg->stripe_unit);
 787         tmp += flseg->first_stripe_index;
 788         return do_div(tmp, flseg->dsaddr->stripe_count);
 789 }
 790
 791 u32
 792 nfs4_fl_calc_ds_index(struct pnfs_layout_segment *lseg, u32 j)
 793 {
 794         return FILELAYOUT_LSEG(lseg)->dsaddr->stripe_indices[j];
 795 }
 796
 797 struct nfs_fh *
 798 nfs4_fl_select_ds_fh(struct pnfs_layout_segment *lseg, u32 j)
 799 {
 800         struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
 801         u32 i;
 802
 803         if (flseg->stripe_type == STRIPE_SPARSE) {
 804                 if (flseg->num_fh == 1)
 805                         i = 0;
 806                 else if (flseg->num_fh == 0)
 807                         /* Use the MDS OPEN fh set in nfs_read_rpcsetup */
 808                         return NULL;
 809                 else
 810                         i = nfs4_fl_calc_ds_index(lseg, j);
 811         } else
 812                 i = j;
 813         return flseg->fh_array[i];
 814 }
 815
 816 static void
 817 filelayout_mark_devid_negative(struct nfs4_file_layout_dsaddr *dsaddr,
 818                                int err, const char *ds_remotestr)
 819 {
 820         u32 *p = (u32 *)&dsaddr->id_node.deviceid;
 821
 822         printk(KERN_ERR "NFS: data server %s connection error %d."
 823                 " Deviceid [%x%x%x%x] marked out of use.\n",
 824                 ds_remotestr, err, p[0], p[1], p[2], p[3]);
 825
 826         spin_lock(&nfs4_ds_cache_lock);
 827         dsaddr->flags |= NFS4_DEVICE_ID_NEG_ENTRY;
 828         spin_unlock(&nfs4_ds_cache_lock);
 829 }
 830
 831 struct nfs4_pnfs_ds *
 832 nfs4_fl_prepare_ds(struct pnfs_layout_segment *lseg, u32 ds_idx)
 833 {
 834         struct nfs4_file_layout_dsaddr *dsaddr = FILELAYOUT_LSEG(lseg)->dsaddr;
 835         struct nfs4_pnfs_ds *ds = dsaddr->ds_list[ds_idx];
 836
 837         if (ds == NULL) {
 838                 printk(KERN_ERR "%s: No data server for offset index %d\n",
 839                         __func__, ds_idx);
 840                 return NULL;
 841         }
 842
 843         if (!ds->ds_clp) {
 844                 struct nfs_server *s = NFS_SERVER(lseg->pls_layout->plh_inode);
 845                 int err;
 846
 847                 if (dsaddr->flags & NFS4_DEVICE_ID_NEG_ENTRY) {
 848                         /* Already tried to connect, don't try again */
 849                         dprintk("%s Deviceid marked out of use\n", __func__);
 850                         return NULL;
 851                 }
 852                 err = nfs4_ds_connect(s, ds);
 853                 if (err) {
 854                         filelayout_mark_devid_negative(dsaddr, err,
 855                                                        ds->ds_remotestr);
 856                         return NULL;
 857                 }
 858         }
 859         return ds;
 860 }