fs/nfs/blocklayout/dev.c

   1 /*
   2  * Copyright (c) 2014-2016 Christoph Hellwig.
   3  */
   4 #include <linux/sunrpc/svc.h>
   5 #include <linux/blkdev.h>
   6 #include <linux/nfs4.h>
   7 #include <linux/nfs_fs.h>
   8 #include <linux/nfs_xdr.h>
   9 #include <linux/pr.h>
  10
  11 #include "blocklayout.h"
  12
  13 #define NFSDBG_FACILITY         NFSDBG_PNFS_LD
  14
  15 static void
  16 bl_free_device(struct pnfs_block_dev *dev)
  17 {
  18         if (dev->nr_children) {
  19                 int i;
  20
  21                 for (i = 0; i < dev->nr_children; i++)
  22                         bl_free_device(&dev->children[i]);
  23                 kfree(dev->children);
  24         } else {
  25                 if (dev->pr_registered) {
  26                         const struct pr_ops *ops =
  27                                 dev->bdev->bd_disk->fops->pr_ops;
  28                         int error;
  29
  30                         error = ops->pr_register(dev->bdev, dev->pr_key, 0,
  31                                 false);
  32                         if (error)
  33                                 pr_err("failed to unregister PR key.\n");
  34                 }
  35
  36                 if (dev->bdev)
  37                         blkdev_put(dev->bdev, FMODE_READ | FMODE_WRITE);
  38         }
  39 }
  40
  41 void
  42 bl_free_deviceid_node(struct nfs4_deviceid_node *d)
  43 {
  44         struct pnfs_block_dev *dev =
  45                 container_of(d, struct pnfs_block_dev, node);
  46
  47         bl_free_device(dev);
  48         kfree_rcu(dev, node.rcu);
  49 }
  50
  51 static int
  52 nfs4_block_decode_volume(struct xdr_stream *xdr, struct pnfs_block_volume *b)
  53 {
  54         __be32 *p;
  55         int i;
  56
  57         p = xdr_inline_decode(xdr, 4);
  58         if (!p)
  59                 return -EIO;
  60         b->type = be32_to_cpup(p++);
  61
  62         switch (b->type) {
  63         case PNFS_BLOCK_VOLUME_SIMPLE:
  64                 p = xdr_inline_decode(xdr, 4);
  65                 if (!p)
  66                         return -EIO;
  67                 b->simple.nr_sigs = be32_to_cpup(p++);
  68                 if (!b->simple.nr_sigs) {
  69                         dprintk("no signature\n");
  70                         return -EIO;
  71                 }
  72
  73                 b->simple.len = 4 + 4;
  74                 for (i = 0; i < b->simple.nr_sigs; i++) {
  75                         p = xdr_inline_decode(xdr, 8 + 4);
  76                         if (!p)
  77                                 return -EIO;
  78                         p = xdr_decode_hyper(p, &b->simple.sigs[i].offset);
  79                         b->simple.sigs[i].sig_len = be32_to_cpup(p++);
  80                         if (b->simple.sigs[i].sig_len > PNFS_BLOCK_UUID_LEN) {
  81                                 pr_info("signature too long: %d\n",
  82                                         b->simple.sigs[i].sig_len);
  83                                 return -EIO;
  84                         }
  85
  86                         p = xdr_inline_decode(xdr, b->simple.sigs[i].sig_len);
  87                         if (!p)
  88                                 return -EIO;
  89                         memcpy(&b->simple.sigs[i].sig, p,
  90                                 b->simple.sigs[i].sig_len);
  91
  92                         b->simple.len += 8 + 4 + \
  93                                 (XDR_QUADLEN(b->simple.sigs[i].sig_len) << 2);
  94                 }
  95                 break;
  96         case PNFS_BLOCK_VOLUME_SLICE:
  97                 p = xdr_inline_decode(xdr, 8 + 8 + 4);
  98                 if (!p)
  99                         return -EIO;
 100                 p = xdr_decode_hyper(p, &b->slice.start);
 101                 p = xdr_decode_hyper(p, &b->slice.len);
 102                 b->slice.volume = be32_to_cpup(p++);
 103                 break;
 104         case PNFS_BLOCK_VOLUME_CONCAT:
 105                 p = xdr_inline_decode(xdr, 4);
 106                 if (!p)
 107                         return -EIO;
 108                 b->concat.volumes_count = be32_to_cpup(p++);
 109
 110                 p = xdr_inline_decode(xdr, b->concat.volumes_count * 4);
 111                 if (!p)
 112                         return -EIO;
 113                 for (i = 0; i < b->concat.volumes_count; i++)
 114                         b->concat.volumes[i] = be32_to_cpup(p++);
 115                 break;
 116         case PNFS_BLOCK_VOLUME_STRIPE:
 117                 p = xdr_inline_decode(xdr, 8 + 4);
 118                 if (!p)
 119                         return -EIO;
 120                 p = xdr_decode_hyper(p, &b->stripe.chunk_size);
 121                 b->stripe.volumes_count = be32_to_cpup(p++);
 122
 123                 p = xdr_inline_decode(xdr, b->stripe.volumes_count * 4);
 124                 if (!p)
 125                         return -EIO;
 126                 for (i = 0; i < b->stripe.volumes_count; i++)
 127                         b->stripe.volumes[i] = be32_to_cpup(p++);
 128                 break;
 129         case PNFS_BLOCK_VOLUME_SCSI:
 130                 p = xdr_inline_decode(xdr, 4 + 4 + 4);
 131                 if (!p)
 132                         return -EIO;
 133                 b->scsi.code_set = be32_to_cpup(p++);
 134                 b->scsi.designator_type = be32_to_cpup(p++);
 135                 b->scsi.designator_len = be32_to_cpup(p++);
 136                 p = xdr_inline_decode(xdr, b->scsi.designator_len);
 137                 if (!p)
 138                         return -EIO;
 139                 if (b->scsi.designator_len > 256)
 140                         return -EIO;
 141                 memcpy(&b->scsi.designator, p, b->scsi.designator_len);
 142                 p = xdr_inline_decode(xdr, 8);
 143                 if (!p)
 144                         return -EIO;
 145                 p = xdr_decode_hyper(p, &b->scsi.pr_key);
 146                 break;
 147         default:
 148                 dprintk("unknown volume type!\n");
 149                 return -EIO;
 150         }
 151
 152         return 0;
 153 }
 154
 155 static bool bl_map_simple(struct pnfs_block_dev *dev, u64 offset,
 156                 struct pnfs_block_dev_map *map)
 157 {
 158         map->start = dev->start;
 159         map->len = dev->len;
 160         map->disk_offset = dev->disk_offset;
 161         map->bdev = dev->bdev;
 162         return true;
 163 }
 164
 165 static bool bl_map_concat(struct pnfs_block_dev *dev, u64 offset,
 166                 struct pnfs_block_dev_map *map)
 167 {
 168         int i;
 169
 170         for (i = 0; i < dev->nr_children; i++) {
 171                 struct pnfs_block_dev *child = &dev->children[i];
 172
 173                 if (child->start > offset ||
 174                     child->start + child->len <= offset)
 175                         continue;
 176
 177                 child->map(child, offset - child->start, map);
 178                 return true;
 179         }
 180
 181         dprintk("%s: ran off loop!\n", __func__);
 182         return false;
 183 }
 184
 185 static bool bl_map_stripe(struct pnfs_block_dev *dev, u64 offset,
 186                 struct pnfs_block_dev_map *map)
 187 {
 188         struct pnfs_block_dev *child;
 189         u64 chunk;
 190         u32 chunk_idx;
 191         u64 disk_offset;
 192
 193         chunk = div_u64(offset, dev->chunk_size);
 194         div_u64_rem(chunk, dev->nr_children, &chunk_idx);
 195
 196         if (chunk_idx > dev->nr_children) {
 197                 dprintk("%s: invalid chunk idx %d (%lld/%lld)\n",
 198                         __func__, chunk_idx, offset, dev->chunk_size);
 199                 /* error, should not happen */
 200                 return false;
 201         }
 202
 203         /* truncate offset to the beginning of the stripe */
 204         offset = chunk * dev->chunk_size;
 205
 206         /* disk offset of the stripe */
 207         disk_offset = div_u64(offset, dev->nr_children);
 208
 209         child = &dev->children[chunk_idx];
 210         child->map(child, disk_offset, map);
 211
 212         map->start += offset;
 213         map->disk_offset += disk_offset;
 214         map->len = dev->chunk_size;
 215         return true;
 216 }
 217
 218 static int
 219 bl_parse_deviceid(struct nfs_server *server, struct pnfs_block_dev *d,
 220                 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask);
 221
 222
 223 static int
 224 bl_parse_simple(struct nfs_server *server, struct pnfs_block_dev *d,
 225                 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
 226 {
 227         struct pnfs_block_volume *v = &volumes[idx];
 228         dev_t dev;
 229
 230         dev = bl_resolve_deviceid(server, v, gfp_mask);
 231         if (!dev)
 232                 return -EIO;
 233
 234         d->bdev = blkdev_get_by_dev(dev, FMODE_READ | FMODE_WRITE, NULL);
 235         if (IS_ERR(d->bdev)) {
 236                 printk(KERN_WARNING "pNFS: failed to open device %d:%d (%ld)\n",
 237                         MAJOR(dev), MINOR(dev), PTR_ERR(d->bdev));
 238                 return PTR_ERR(d->bdev);
 239         }
 240
 241
 242         d->len = i_size_read(d->bdev->bd_inode);
 243         d->map = bl_map_simple;
 244
 245         printk(KERN_INFO "pNFS: using block device %s\n",
 246                 d->bdev->bd_disk->disk_name);
 247         return 0;
 248 }
 249
 250 static bool
 251 bl_validate_designator(struct pnfs_block_volume *v)
 252 {
 253         switch (v->scsi.designator_type) {
 254         case PS_DESIGNATOR_EUI64:
 255                 if (v->scsi.code_set != PS_CODE_SET_BINARY)
 256                         return false;
 257
 258                 if (v->scsi.designator_len != 8 &&
 259                     v->scsi.designator_len != 10 &&
 260                     v->scsi.designator_len != 16)
 261                         return false;
 262
 263                 return true;
 264         case PS_DESIGNATOR_NAA:
 265                 if (v->scsi.code_set != PS_CODE_SET_BINARY)
 266                         return false;
 267
 268                 if (v->scsi.designator_len != 8 &&
 269                     v->scsi.designator_len != 16)
 270                         return false;
 271
 272                 return true;
 273         case PS_DESIGNATOR_T10:
 274         case PS_DESIGNATOR_NAME:
 275                 pr_err("pNFS: unsupported designator "
 276                         "(code set %d, type %d, len %d.\n",
 277                         v->scsi.code_set,
 278                         v->scsi.designator_type,
 279                         v->scsi.designator_len);
 280                 return false;
 281         default:
 282                 pr_err("pNFS: invalid designator "
 283                         "(code set %d, type %d, len %d.\n",
 284                         v->scsi.code_set,
 285                         v->scsi.designator_type,
 286                         v->scsi.designator_len);
 287                 return false;
 288         }
 289 }
 290
 291 /*
 292  * Try to open the udev path for the WWN.  At least on Debian the udev
 293  * by-id path will always point to the dm-multipath device if one exists.
 294  */
 295 static struct block_device *
 296 bl_open_udev_path(struct pnfs_block_volume *v)
 297 {
 298         struct block_device *bdev;
 299         const char *devname;
 300
 301         devname = kasprintf(GFP_KERNEL, "/dev/disk/by-id/wwn-0x%*phN",
 302                                 v->scsi.designator_len, v->scsi.designator);
 303         if (!devname)
 304                 return ERR_PTR(-ENOMEM);
 305
 306         bdev = blkdev_get_by_path(devname, FMODE_READ | FMODE_WRITE, NULL);
 307         if (IS_ERR(bdev)) {
 308                 pr_warn("pNFS: failed to open device %s (%ld)\n",
 309                         devname, PTR_ERR(bdev));
 310         }
 311
 312         kfree(devname);
 313         return bdev;
 314 }
 315
 316 /*
 317  * Try to open the RH/Fedora specific dm-mpath udev path for this WWN, as the
 318  * wwn- links will only point to the first discovered SCSI device there.
 319  */
 320 static struct block_device *
 321 bl_open_dm_mpath_udev_path(struct pnfs_block_volume *v)
 322 {
 323         struct block_device *bdev;
 324         const char *devname;
 325
 326         devname = kasprintf(GFP_KERNEL,
 327                         "/dev/disk/by-id/dm-uuid-mpath-%d%*phN",
 328                         v->scsi.designator_type,
 329                         v->scsi.designator_len, v->scsi.designator);
 330         if (!devname)
 331                 return ERR_PTR(-ENOMEM);
 332
 333         bdev = blkdev_get_by_path(devname, FMODE_READ | FMODE_WRITE, NULL);
 334         kfree(devname);
 335         return bdev;
 336 }
 337
 338 static int
 339 bl_parse_scsi(struct nfs_server *server, struct pnfs_block_dev *d,
 340                 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
 341 {
 342         struct pnfs_block_volume *v = &volumes[idx];
 343         const struct pr_ops *ops;
 344         int error;
 345
 346         if (!bl_validate_designator(v))
 347                 return -EINVAL;
 348
 349         d->bdev = bl_open_dm_mpath_udev_path(v);
 350         if (IS_ERR(d->bdev))
 351                 d->bdev = bl_open_udev_path(v);
 352         if (IS_ERR(d->bdev))
 353                 return PTR_ERR(d->bdev);
 354
 355         d->len = i_size_read(d->bdev->bd_inode);
 356         d->map = bl_map_simple;
 357         d->pr_key = v->scsi.pr_key;
 358
 359         pr_info("pNFS: using block device %s (reservation key 0x%llx)\n",
 360                 d->bdev->bd_disk->disk_name, d->pr_key);
 361
 362         ops = d->bdev->bd_disk->fops->pr_ops;
 363         if (!ops) {
 364                 pr_err("pNFS: block device %s does not support reservations.",
 365                                 d->bdev->bd_disk->disk_name);
 366                 error = -EINVAL;
 367                 goto out_blkdev_put;
 368         }
 369
 370         error = ops->pr_register(d->bdev, 0, d->pr_key, true);
 371         if (error) {
 372                 pr_err("pNFS: failed to register key for block device %s.",
 373                                 d->bdev->bd_disk->disk_name);
 374                 goto out_blkdev_put;
 375         }
 376
 377         d->pr_registered = true;
 378         return 0;
 379
 380 out_blkdev_put:
 381         blkdev_put(d->bdev, FMODE_READ | FMODE_WRITE);
 382         return error;
 383 }
 384
 385 static int
 386 bl_parse_slice(struct nfs_server *server, struct pnfs_block_dev *d,
 387                 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
 388 {
 389         struct pnfs_block_volume *v = &volumes[idx];
 390         int ret;
 391
 392         ret = bl_parse_deviceid(server, d, volumes, v->slice.volume, gfp_mask);
 393         if (ret)
 394                 return ret;
 395
 396         d->disk_offset = v->slice.start;
 397         d->len = v->slice.len;
 398         return 0;
 399 }
 400
 401 static int
 402 bl_parse_concat(struct nfs_server *server, struct pnfs_block_dev *d,
 403                 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
 404 {
 405         struct pnfs_block_volume *v = &volumes[idx];
 406         u64 len = 0;
 407         int ret, i;
 408
 409         d->children = kcalloc(v->concat.volumes_count,
 410                         sizeof(struct pnfs_block_dev), GFP_KERNEL);
 411         if (!d->children)
 412                 return -ENOMEM;
 413
 414         for (i = 0; i < v->concat.volumes_count; i++) {
 415                 ret = bl_parse_deviceid(server, &d->children[i],
 416                                 volumes, v->concat.volumes[i], gfp_mask);
 417                 if (ret)
 418                         return ret;
 419
 420                 d->nr_children++;
 421                 d->children[i].start += len;
 422                 len += d->children[i].len;
 423         }
 424
 425         d->len = len;
 426         d->map = bl_map_concat;
 427         return 0;
 428 }
 429
 430 static int
 431 bl_parse_stripe(struct nfs_server *server, struct pnfs_block_dev *d,
 432                 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
 433 {
 434         struct pnfs_block_volume *v = &volumes[idx];
 435         u64 len = 0;
 436         int ret, i;
 437
 438         d->children = kcalloc(v->stripe.volumes_count,
 439                         sizeof(struct pnfs_block_dev), GFP_KERNEL);
 440         if (!d->children)
 441                 return -ENOMEM;
 442
 443         for (i = 0; i < v->stripe.volumes_count; i++) {
 444                 ret = bl_parse_deviceid(server, &d->children[i],
 445                                 volumes, v->stripe.volumes[i], gfp_mask);
 446                 if (ret)
 447                         return ret;
 448
 449                 d->nr_children++;
 450                 len += d->children[i].len;
 451         }
 452
 453         d->len = len;
 454         d->chunk_size = v->stripe.chunk_size;
 455         d->map = bl_map_stripe;
 456         return 0;
 457 }
 458
 459 static int
 460 bl_parse_deviceid(struct nfs_server *server, struct pnfs_block_dev *d,
 461                 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
 462 {
 463         switch (volumes[idx].type) {
 464         case PNFS_BLOCK_VOLUME_SIMPLE:
 465                 return bl_parse_simple(server, d, volumes, idx, gfp_mask);
 466         case PNFS_BLOCK_VOLUME_SLICE:
 467                 return bl_parse_slice(server, d, volumes, idx, gfp_mask);
 468         case PNFS_BLOCK_VOLUME_CONCAT:
 469                 return bl_parse_concat(server, d, volumes, idx, gfp_mask);
 470         case PNFS_BLOCK_VOLUME_STRIPE:
 471                 return bl_parse_stripe(server, d, volumes, idx, gfp_mask);
 472         case PNFS_BLOCK_VOLUME_SCSI:
 473                 return bl_parse_scsi(server, d, volumes, idx, gfp_mask);
 474         default:
 475                 dprintk("unsupported volume type: %d\n", volumes[idx].type);
 476                 return -EIO;
 477         }
 478 }
 479
 480 struct nfs4_deviceid_node *
 481 bl_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *pdev,
 482                 gfp_t gfp_mask)
 483 {
 484         struct nfs4_deviceid_node *node = NULL;
 485         struct pnfs_block_volume *volumes;
 486         struct pnfs_block_dev *top;
 487         struct xdr_stream xdr;
 488         struct xdr_buf buf;
 489         struct page *scratch;
 490         int nr_volumes, ret, i;
 491         __be32 *p;
 492
 493         scratch = alloc_page(gfp_mask);
 494         if (!scratch)
 495                 goto out;
 496
 497         xdr_init_decode_pages(&xdr, &buf, pdev->pages, pdev->pglen);
 498         xdr_set_scratch_buffer(&xdr, page_address(scratch), PAGE_SIZE);
 499
 500         p = xdr_inline_decode(&xdr, sizeof(__be32));
 501         if (!p)
 502                 goto out_free_scratch;
 503         nr_volumes = be32_to_cpup(p++);
 504
 505         volumes = kcalloc(nr_volumes, sizeof(struct pnfs_block_volume),
 506                           gfp_mask);
 507         if (!volumes)
 508                 goto out_free_scratch;
 509
 510         for (i = 0; i < nr_volumes; i++) {
 511                 ret = nfs4_block_decode_volume(&xdr, &volumes[i]);
 512                 if (ret < 0)
 513                         goto out_free_volumes;
 514         }
 515
 516         top = kzalloc(sizeof(*top), gfp_mask);
 517         if (!top)
 518                 goto out_free_volumes;
 519
 520         ret = bl_parse_deviceid(server, top, volumes, nr_volumes - 1, gfp_mask);
 521         if (ret) {
 522                 bl_free_device(top);
 523                 kfree(top);
 524                 goto out_free_volumes;
 525         }
 526
 527         node = &top->node;
 528         nfs4_init_deviceid_node(node, server, &pdev->dev_id);
 529
 530 out_free_volumes:
 531         kfree(volumes);
 532 out_free_scratch:
 533         __free_page(scratch);
 534 out:
 535         return node;
 536 }