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 || b->simple.nr_sigs > PNFS_BLOCK_MAX_UUIDS) {
  69                         dprintk("Bad signature count: %d\n", b->simple.nr_sigs);
  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
 109                 b->concat.volumes_count = be32_to_cpup(p++);
 110                 if (b->concat.volumes_count > PNFS_BLOCK_MAX_DEVICES) {
 111                         dprintk("Too many volumes: %d\n", b->concat.volumes_count);
 112                         return -EIO;
 113                 }
 114
 115                 p = xdr_inline_decode(xdr, b->concat.volumes_count * 4);
 116                 if (!p)
 117                         return -EIO;
 118                 for (i = 0; i < b->concat.volumes_count; i++)
 119                         b->concat.volumes[i] = be32_to_cpup(p++);
 120                 break;
 121         case PNFS_BLOCK_VOLUME_STRIPE:
 122                 p = xdr_inline_decode(xdr, 8 + 4);
 123                 if (!p)
 124                         return -EIO;
 125
 126                 p = xdr_decode_hyper(p, &b->stripe.chunk_size);
 127                 b->stripe.volumes_count = be32_to_cpup(p++);
 128                 if (b->stripe.volumes_count > PNFS_BLOCK_MAX_DEVICES) {
 129                         dprintk("Too many volumes: %d\n", b->stripe.volumes_count);
 130                         return -EIO;
 131                 }
 132
 133                 p = xdr_inline_decode(xdr, b->stripe.volumes_count * 4);
 134                 if (!p)
 135                         return -EIO;
 136                 for (i = 0; i < b->stripe.volumes_count; i++)
 137                         b->stripe.volumes[i] = be32_to_cpup(p++);
 138                 break;
 139         case PNFS_BLOCK_VOLUME_SCSI:
 140                 p = xdr_inline_decode(xdr, 4 + 4 + 4);
 141                 if (!p)
 142                         return -EIO;
 143                 b->scsi.code_set = be32_to_cpup(p++);
 144                 b->scsi.designator_type = be32_to_cpup(p++);
 145                 b->scsi.designator_len = be32_to_cpup(p++);
 146                 p = xdr_inline_decode(xdr, b->scsi.designator_len);
 147                 if (!p)
 148                         return -EIO;
 149                 if (b->scsi.designator_len > 256)
 150                         return -EIO;
 151                 memcpy(&b->scsi.designator, p, b->scsi.designator_len);
 152                 p = xdr_inline_decode(xdr, 8);
 153                 if (!p)
 154                         return -EIO;
 155                 p = xdr_decode_hyper(p, &b->scsi.pr_key);
 156                 break;
 157         default:
 158                 dprintk("unknown volume type!\n");
 159                 return -EIO;
 160         }
 161
 162         return 0;
 163 }
 164
 165 static bool bl_map_simple(struct pnfs_block_dev *dev, u64 offset,
 166                 struct pnfs_block_dev_map *map)
 167 {
 168         map->start = dev->start;
 169         map->len = dev->len;
 170         map->disk_offset = dev->disk_offset;
 171         map->bdev = dev->bdev;
 172         return true;
 173 }
 174
 175 static bool bl_map_concat(struct pnfs_block_dev *dev, u64 offset,
 176                 struct pnfs_block_dev_map *map)
 177 {
 178         int i;
 179
 180         for (i = 0; i < dev->nr_children; i++) {
 181                 struct pnfs_block_dev *child = &dev->children[i];
 182
 183                 if (child->start > offset ||
 184                     child->start + child->len <= offset)
 185                         continue;
 186
 187                 child->map(child, offset - child->start, map);
 188                 return true;
 189         }
 190
 191         dprintk("%s: ran off loop!\n", __func__);
 192         return false;
 193 }
 194
 195 static bool bl_map_stripe(struct pnfs_block_dev *dev, u64 offset,
 196                 struct pnfs_block_dev_map *map)
 197 {
 198         struct pnfs_block_dev *child;
 199         u64 chunk;
 200         u32 chunk_idx;
 201         u64 disk_offset;
 202
 203         chunk = div_u64(offset, dev->chunk_size);
 204         div_u64_rem(chunk, dev->nr_children, &chunk_idx);
 205
 206         if (chunk_idx >= dev->nr_children) {
 207                 dprintk("%s: invalid chunk idx %d (%lld/%lld)\n",
 208                         __func__, chunk_idx, offset, dev->chunk_size);
 209                 /* error, should not happen */
 210                 return false;
 211         }
 212
 213         /* truncate offset to the beginning of the stripe */
 214         offset = chunk * dev->chunk_size;
 215
 216         /* disk offset of the stripe */
 217         disk_offset = div_u64(offset, dev->nr_children);
 218
 219         child = &dev->children[chunk_idx];
 220         child->map(child, disk_offset, map);
 221
 222         map->start += offset;
 223         map->disk_offset += disk_offset;
 224         map->len = dev->chunk_size;
 225         return true;
 226 }
 227
 228 static int
 229 bl_parse_deviceid(struct nfs_server *server, struct pnfs_block_dev *d,
 230                 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask);
 231
 232
 233 static int
 234 bl_parse_simple(struct nfs_server *server, struct pnfs_block_dev *d,
 235                 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
 236 {
 237         struct pnfs_block_volume *v = &volumes[idx];
 238         struct block_device *bdev;
 239         dev_t dev;
 240
 241         dev = bl_resolve_deviceid(server, v, gfp_mask);
 242         if (!dev)
 243                 return -EIO;
 244
 245         bdev = blkdev_get_by_dev(dev, FMODE_READ | FMODE_WRITE, NULL);
 246         if (IS_ERR(bdev)) {
 247                 printk(KERN_WARNING "pNFS: failed to open device %d:%d (%ld)\n",
 248                         MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
 249                 return PTR_ERR(bdev);
 250         }
 251         d->bdev = bdev;
 252
 253
 254         d->len = i_size_read(d->bdev->bd_inode);
 255         d->map = bl_map_simple;
 256
 257         printk(KERN_INFO "pNFS: using block device %s\n",
 258                 d->bdev->bd_disk->disk_name);
 259         return 0;
 260 }
 261
 262 static bool
 263 bl_validate_designator(struct pnfs_block_volume *v)
 264 {
 265         switch (v->scsi.designator_type) {
 266         case PS_DESIGNATOR_EUI64:
 267                 if (v->scsi.code_set != PS_CODE_SET_BINARY)
 268                         return false;
 269
 270                 if (v->scsi.designator_len != 8 &&
 271                     v->scsi.designator_len != 10 &&
 272                     v->scsi.designator_len != 16)
 273                         return false;
 274
 275                 return true;
 276         case PS_DESIGNATOR_NAA:
 277                 if (v->scsi.code_set != PS_CODE_SET_BINARY)
 278                         return false;
 279
 280                 if (v->scsi.designator_len != 8 &&
 281                     v->scsi.designator_len != 16)
 282                         return false;
 283
 284                 return true;
 285         case PS_DESIGNATOR_T10:
 286         case PS_DESIGNATOR_NAME:
 287                 pr_err("pNFS: unsupported designator "
 288                         "(code set %d, type %d, len %d.\n",
 289                         v->scsi.code_set,
 290                         v->scsi.designator_type,
 291                         v->scsi.designator_len);
 292                 return false;
 293         default:
 294                 pr_err("pNFS: invalid designator "
 295                         "(code set %d, type %d, len %d.\n",
 296                         v->scsi.code_set,
 297                         v->scsi.designator_type,
 298                         v->scsi.designator_len);
 299                 return false;
 300         }
 301 }
 302
 303 /*
 304  * Try to open the udev path for the WWN.  At least on Debian the udev
 305  * by-id path will always point to the dm-multipath device if one exists.
 306  */
 307 static struct block_device *
 308 bl_open_udev_path(struct pnfs_block_volume *v)
 309 {
 310         struct block_device *bdev;
 311         const char *devname;
 312
 313         devname = kasprintf(GFP_KERNEL, "/dev/disk/by-id/wwn-0x%*phN",
 314                                 v->scsi.designator_len, v->scsi.designator);
 315         if (!devname)
 316                 return ERR_PTR(-ENOMEM);
 317
 318         bdev = blkdev_get_by_path(devname, FMODE_READ | FMODE_WRITE, NULL);
 319         if (IS_ERR(bdev)) {
 320                 pr_warn("pNFS: failed to open device %s (%ld)\n",
 321                         devname, PTR_ERR(bdev));
 322         }
 323
 324         kfree(devname);
 325         return bdev;
 326 }
 327
 328 /*
 329  * Try to open the RH/Fedora specific dm-mpath udev path for this WWN, as the
 330  * wwn- links will only point to the first discovered SCSI device there.
 331  */
 332 static struct block_device *
 333 bl_open_dm_mpath_udev_path(struct pnfs_block_volume *v)
 334 {
 335         struct block_device *bdev;
 336         const char *devname;
 337
 338         devname = kasprintf(GFP_KERNEL,
 339                         "/dev/disk/by-id/dm-uuid-mpath-%d%*phN",
 340                         v->scsi.designator_type,
 341                         v->scsi.designator_len, v->scsi.designator);
 342         if (!devname)
 343                 return ERR_PTR(-ENOMEM);
 344
 345         bdev = blkdev_get_by_path(devname, FMODE_READ | FMODE_WRITE, NULL);
 346         kfree(devname);
 347         return bdev;
 348 }
 349
 350 static int
 351 bl_parse_scsi(struct nfs_server *server, struct pnfs_block_dev *d,
 352                 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
 353 {
 354         struct pnfs_block_volume *v = &volumes[idx];
 355         struct block_device *bdev;
 356         const struct pr_ops *ops;
 357         int error;
 358
 359         if (!bl_validate_designator(v))
 360                 return -EINVAL;
 361
 362         bdev = bl_open_dm_mpath_udev_path(v);
 363         if (IS_ERR(bdev))
 364                 bdev = bl_open_udev_path(v);
 365         if (IS_ERR(bdev))
 366                 return PTR_ERR(bdev);
 367         d->bdev = bdev;
 368
 369         d->len = i_size_read(d->bdev->bd_inode);
 370         d->map = bl_map_simple;
 371         d->pr_key = v->scsi.pr_key;
 372
 373         pr_info("pNFS: using block device %s (reservation key 0x%llx)\n",
 374                 d->bdev->bd_disk->disk_name, d->pr_key);
 375
 376         ops = d->bdev->bd_disk->fops->pr_ops;
 377         if (!ops) {
 378                 pr_err("pNFS: block device %s does not support reservations.",
 379                                 d->bdev->bd_disk->disk_name);
 380                 error = -EINVAL;
 381                 goto out_blkdev_put;
 382         }
 383
 384         error = ops->pr_register(d->bdev, 0, d->pr_key, true);
 385         if (error) {
 386                 pr_err("pNFS: failed to register key for block device %s.",
 387                                 d->bdev->bd_disk->disk_name);
 388                 goto out_blkdev_put;
 389         }
 390
 391         d->pr_registered = true;
 392         return 0;
 393
 394 out_blkdev_put:
 395         blkdev_put(d->bdev, FMODE_READ | FMODE_WRITE);
 396         return error;
 397 }
 398
 399 static int
 400 bl_parse_slice(struct nfs_server *server, struct pnfs_block_dev *d,
 401                 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
 402 {
 403         struct pnfs_block_volume *v = &volumes[idx];
 404         int ret;
 405
 406         ret = bl_parse_deviceid(server, d, volumes, v->slice.volume, gfp_mask);
 407         if (ret)
 408                 return ret;
 409
 410         d->disk_offset = v->slice.start;
 411         d->len = v->slice.len;
 412         return 0;
 413 }
 414
 415 static int
 416 bl_parse_concat(struct nfs_server *server, struct pnfs_block_dev *d,
 417                 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
 418 {
 419         struct pnfs_block_volume *v = &volumes[idx];
 420         u64 len = 0;
 421         int ret, i;
 422
 423         d->children = kcalloc(v->concat.volumes_count,
 424                         sizeof(struct pnfs_block_dev), GFP_KERNEL);
 425         if (!d->children)
 426                 return -ENOMEM;
 427
 428         for (i = 0; i < v->concat.volumes_count; i++) {
 429                 ret = bl_parse_deviceid(server, &d->children[i],
 430                                 volumes, v->concat.volumes[i], gfp_mask);
 431                 if (ret)
 432                         return ret;
 433
 434                 d->nr_children++;
 435                 d->children[i].start += len;
 436                 len += d->children[i].len;
 437         }
 438
 439         d->len = len;
 440         d->map = bl_map_concat;
 441         return 0;
 442 }
 443
 444 static int
 445 bl_parse_stripe(struct nfs_server *server, struct pnfs_block_dev *d,
 446                 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
 447 {
 448         struct pnfs_block_volume *v = &volumes[idx];
 449         u64 len = 0;
 450         int ret, i;
 451
 452         d->children = kcalloc(v->stripe.volumes_count,
 453                         sizeof(struct pnfs_block_dev), GFP_KERNEL);
 454         if (!d->children)
 455                 return -ENOMEM;
 456
 457         for (i = 0; i < v->stripe.volumes_count; i++) {
 458                 ret = bl_parse_deviceid(server, &d->children[i],
 459                                 volumes, v->stripe.volumes[i], gfp_mask);
 460                 if (ret)
 461                         return ret;
 462
 463                 d->nr_children++;
 464                 len += d->children[i].len;
 465         }
 466
 467         d->len = len;
 468         d->chunk_size = v->stripe.chunk_size;
 469         d->map = bl_map_stripe;
 470         return 0;
 471 }
 472
 473 static int
 474 bl_parse_deviceid(struct nfs_server *server, struct pnfs_block_dev *d,
 475                 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
 476 {
 477         switch (volumes[idx].type) {
 478         case PNFS_BLOCK_VOLUME_SIMPLE:
 479                 return bl_parse_simple(server, d, volumes, idx, gfp_mask);
 480         case PNFS_BLOCK_VOLUME_SLICE:
 481                 return bl_parse_slice(server, d, volumes, idx, gfp_mask);
 482         case PNFS_BLOCK_VOLUME_CONCAT:
 483                 return bl_parse_concat(server, d, volumes, idx, gfp_mask);
 484         case PNFS_BLOCK_VOLUME_STRIPE:
 485                 return bl_parse_stripe(server, d, volumes, idx, gfp_mask);
 486         case PNFS_BLOCK_VOLUME_SCSI:
 487                 return bl_parse_scsi(server, d, volumes, idx, gfp_mask);
 488         default:
 489                 dprintk("unsupported volume type: %d\n", volumes[idx].type);
 490                 return -EIO;
 491         }
 492 }
 493
 494 struct nfs4_deviceid_node *
 495 bl_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *pdev,
 496                 gfp_t gfp_mask)
 497 {
 498         struct nfs4_deviceid_node *node = NULL;
 499         struct pnfs_block_volume *volumes;
 500         struct pnfs_block_dev *top;
 501         struct xdr_stream xdr;
 502         struct xdr_buf buf;
 503         struct page *scratch;
 504         int nr_volumes, ret, i;
 505         __be32 *p;
 506
 507         scratch = alloc_page(gfp_mask);
 508         if (!scratch)
 509                 goto out;
 510
 511         xdr_init_decode_pages(&xdr, &buf, pdev->pages, pdev->pglen);
 512         xdr_set_scratch_buffer(&xdr, page_address(scratch), PAGE_SIZE);
 513
 514         p = xdr_inline_decode(&xdr, sizeof(__be32));
 515         if (!p)
 516                 goto out_free_scratch;
 517         nr_volumes = be32_to_cpup(p++);
 518
 519         volumes = kcalloc(nr_volumes, sizeof(struct pnfs_block_volume),
 520                           gfp_mask);
 521         if (!volumes)
 522                 goto out_free_scratch;
 523
 524         for (i = 0; i < nr_volumes; i++) {
 525                 ret = nfs4_block_decode_volume(&xdr, &volumes[i]);
 526                 if (ret < 0)
 527                         goto out_free_volumes;
 528         }
 529
 530         top = kzalloc(sizeof(*top), gfp_mask);
 531         if (!top)
 532                 goto out_free_volumes;
 533
 534         ret = bl_parse_deviceid(server, top, volumes, nr_volumes - 1, gfp_mask);
 535         if (ret) {
 536                 bl_free_device(top);
 537                 kfree(top);
 538                 goto out_free_volumes;
 539         }
 540
 541         node = &top->node;
 542         nfs4_init_deviceid_node(node, server, &pdev->dev_id);
 543
 544 out_free_volumes:
 545         kfree(volumes);
 546 out_free_scratch:
 547         __free_page(scratch);
 548 out:
 549         return node;
 550 }