GNU Linux-libre 6.7.9-gnu
[releases.git] / fs / nfs / blocklayout / dev.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2014-2016 Christoph Hellwig.
4  */
5 #include <linux/sunrpc/svc.h>
6 #include <linux/blkdev.h>
7 #include <linux/nfs4.h>
8 #include <linux/nfs_fs.h>
9 #include <linux/nfs_xdr.h>
10 #include <linux/pr.h>
11
12 #include "blocklayout.h"
13
14 #define NFSDBG_FACILITY         NFSDBG_PNFS_LD
15
16 static void
17 bl_free_device(struct pnfs_block_dev *dev)
18 {
19         if (dev->nr_children) {
20                 int i;
21
22                 for (i = 0; i < dev->nr_children; i++)
23                         bl_free_device(&dev->children[i]);
24                 kfree(dev->children);
25         } else {
26                 if (dev->pr_registered) {
27                         const struct pr_ops *ops =
28                                 dev->bdev_handle->bdev->bd_disk->fops->pr_ops;
29                         int error;
30
31                         error = ops->pr_register(dev->bdev_handle->bdev,
32                                 dev->pr_key, 0, false);
33                         if (error)
34                                 pr_err("failed to unregister PR key.\n");
35                 }
36
37                 if (dev->bdev_handle)
38                         bdev_release(dev->bdev_handle);
39         }
40 }
41
42 void
43 bl_free_deviceid_node(struct nfs4_deviceid_node *d)
44 {
45         struct pnfs_block_dev *dev =
46                 container_of(d, struct pnfs_block_dev, node);
47
48         bl_free_device(dev);
49         kfree_rcu(dev, node.rcu);
50 }
51
52 static int
53 nfs4_block_decode_volume(struct xdr_stream *xdr, struct pnfs_block_volume *b)
54 {
55         __be32 *p;
56         int i;
57
58         p = xdr_inline_decode(xdr, 4);
59         if (!p)
60                 return -EIO;
61         b->type = be32_to_cpup(p++);
62
63         switch (b->type) {
64         case PNFS_BLOCK_VOLUME_SIMPLE:
65                 p = xdr_inline_decode(xdr, 4);
66                 if (!p)
67                         return -EIO;
68                 b->simple.nr_sigs = be32_to_cpup(p++);
69                 if (!b->simple.nr_sigs || b->simple.nr_sigs > PNFS_BLOCK_MAX_UUIDS) {
70                         dprintk("Bad signature count: %d\n", b->simple.nr_sigs);
71                         return -EIO;
72                 }
73
74                 b->simple.len = 4 + 4;
75                 for (i = 0; i < b->simple.nr_sigs; i++) {
76                         p = xdr_inline_decode(xdr, 8 + 4);
77                         if (!p)
78                                 return -EIO;
79                         p = xdr_decode_hyper(p, &b->simple.sigs[i].offset);
80                         b->simple.sigs[i].sig_len = be32_to_cpup(p++);
81                         if (b->simple.sigs[i].sig_len > PNFS_BLOCK_UUID_LEN) {
82                                 pr_info("signature too long: %d\n",
83                                         b->simple.sigs[i].sig_len);
84                                 return -EIO;
85                         }
86
87                         p = xdr_inline_decode(xdr, b->simple.sigs[i].sig_len);
88                         if (!p)
89                                 return -EIO;
90                         memcpy(&b->simple.sigs[i].sig, p,
91                                 b->simple.sigs[i].sig_len);
92
93                         b->simple.len += 8 + 4 + \
94                                 (XDR_QUADLEN(b->simple.sigs[i].sig_len) << 2);
95                 }
96                 break;
97         case PNFS_BLOCK_VOLUME_SLICE:
98                 p = xdr_inline_decode(xdr, 8 + 8 + 4);
99                 if (!p)
100                         return -EIO;
101                 p = xdr_decode_hyper(p, &b->slice.start);
102                 p = xdr_decode_hyper(p, &b->slice.len);
103                 b->slice.volume = be32_to_cpup(p++);
104                 break;
105         case PNFS_BLOCK_VOLUME_CONCAT:
106                 p = xdr_inline_decode(xdr, 4);
107                 if (!p)
108                         return -EIO;
109
110                 b->concat.volumes_count = be32_to_cpup(p++);
111                 if (b->concat.volumes_count > PNFS_BLOCK_MAX_DEVICES) {
112                         dprintk("Too many volumes: %d\n", b->concat.volumes_count);
113                         return -EIO;
114                 }
115
116                 p = xdr_inline_decode(xdr, b->concat.volumes_count * 4);
117                 if (!p)
118                         return -EIO;
119                 for (i = 0; i < b->concat.volumes_count; i++)
120                         b->concat.volumes[i] = be32_to_cpup(p++);
121                 break;
122         case PNFS_BLOCK_VOLUME_STRIPE:
123                 p = xdr_inline_decode(xdr, 8 + 4);
124                 if (!p)
125                         return -EIO;
126
127                 p = xdr_decode_hyper(p, &b->stripe.chunk_size);
128                 b->stripe.volumes_count = be32_to_cpup(p++);
129                 if (b->stripe.volumes_count > PNFS_BLOCK_MAX_DEVICES) {
130                         dprintk("Too many volumes: %d\n", b->stripe.volumes_count);
131                         return -EIO;
132                 }
133
134                 p = xdr_inline_decode(xdr, b->stripe.volumes_count * 4);
135                 if (!p)
136                         return -EIO;
137                 for (i = 0; i < b->stripe.volumes_count; i++)
138                         b->stripe.volumes[i] = be32_to_cpup(p++);
139                 break;
140         case PNFS_BLOCK_VOLUME_SCSI:
141                 p = xdr_inline_decode(xdr, 4 + 4 + 4);
142                 if (!p)
143                         return -EIO;
144                 b->scsi.code_set = be32_to_cpup(p++);
145                 b->scsi.designator_type = be32_to_cpup(p++);
146                 b->scsi.designator_len = be32_to_cpup(p++);
147                 p = xdr_inline_decode(xdr, b->scsi.designator_len);
148                 if (!p)
149                         return -EIO;
150                 if (b->scsi.designator_len > 256)
151                         return -EIO;
152                 memcpy(&b->scsi.designator, p, b->scsi.designator_len);
153                 p = xdr_inline_decode(xdr, 8);
154                 if (!p)
155                         return -EIO;
156                 p = xdr_decode_hyper(p, &b->scsi.pr_key);
157                 break;
158         default:
159                 dprintk("unknown volume type!\n");
160                 return -EIO;
161         }
162
163         return 0;
164 }
165
166 static bool bl_map_simple(struct pnfs_block_dev *dev, u64 offset,
167                 struct pnfs_block_dev_map *map)
168 {
169         map->start = dev->start;
170         map->len = dev->len;
171         map->disk_offset = dev->disk_offset;
172         map->bdev = dev->bdev_handle->bdev;
173         return true;
174 }
175
176 static bool bl_map_concat(struct pnfs_block_dev *dev, u64 offset,
177                 struct pnfs_block_dev_map *map)
178 {
179         int i;
180
181         for (i = 0; i < dev->nr_children; i++) {
182                 struct pnfs_block_dev *child = &dev->children[i];
183
184                 if (child->start > offset ||
185                     child->start + child->len <= offset)
186                         continue;
187
188                 child->map(child, offset - child->start, map);
189                 return true;
190         }
191
192         dprintk("%s: ran off loop!\n", __func__);
193         return false;
194 }
195
196 static bool bl_map_stripe(struct pnfs_block_dev *dev, u64 offset,
197                 struct pnfs_block_dev_map *map)
198 {
199         struct pnfs_block_dev *child;
200         u64 chunk;
201         u32 chunk_idx;
202         u64 disk_offset;
203
204         chunk = div_u64(offset, dev->chunk_size);
205         div_u64_rem(chunk, dev->nr_children, &chunk_idx);
206
207         if (chunk_idx >= dev->nr_children) {
208                 dprintk("%s: invalid chunk idx %d (%lld/%lld)\n",
209                         __func__, chunk_idx, offset, dev->chunk_size);
210                 /* error, should not happen */
211                 return false;
212         }
213
214         /* truncate offset to the beginning of the stripe */
215         offset = chunk * dev->chunk_size;
216
217         /* disk offset of the stripe */
218         disk_offset = div_u64(offset, dev->nr_children);
219
220         child = &dev->children[chunk_idx];
221         child->map(child, disk_offset, map);
222
223         map->start += offset;
224         map->disk_offset += disk_offset;
225         map->len = dev->chunk_size;
226         return true;
227 }
228
229 static int
230 bl_parse_deviceid(struct nfs_server *server, struct pnfs_block_dev *d,
231                 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask);
232
233
234 static int
235 bl_parse_simple(struct nfs_server *server, struct pnfs_block_dev *d,
236                 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
237 {
238         struct pnfs_block_volume *v = &volumes[idx];
239         struct bdev_handle *bdev_handle;
240         dev_t dev;
241
242         dev = bl_resolve_deviceid(server, v, gfp_mask);
243         if (!dev)
244                 return -EIO;
245
246         bdev_handle = bdev_open_by_dev(dev, BLK_OPEN_READ | BLK_OPEN_WRITE,
247                                        NULL, NULL);
248         if (IS_ERR(bdev_handle)) {
249                 printk(KERN_WARNING "pNFS: failed to open device %d:%d (%ld)\n",
250                         MAJOR(dev), MINOR(dev), PTR_ERR(bdev_handle));
251                 return PTR_ERR(bdev_handle);
252         }
253         d->bdev_handle = bdev_handle;
254         d->len = bdev_nr_bytes(bdev_handle->bdev);
255         d->map = bl_map_simple;
256
257         printk(KERN_INFO "pNFS: using block device %s\n",
258                 bdev_handle->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 static struct bdev_handle *
304 bl_open_path(struct pnfs_block_volume *v, const char *prefix)
305 {
306         struct bdev_handle *bdev_handle;
307         const char *devname;
308
309         devname = kasprintf(GFP_KERNEL, "/dev/disk/by-id/%s%*phN",
310                         prefix, v->scsi.designator_len, v->scsi.designator);
311         if (!devname)
312                 return ERR_PTR(-ENOMEM);
313
314         bdev_handle = bdev_open_by_path(devname, BLK_OPEN_READ | BLK_OPEN_WRITE,
315                                         NULL, NULL);
316         if (IS_ERR(bdev_handle)) {
317                 pr_warn("pNFS: failed to open device %s (%ld)\n",
318                         devname, PTR_ERR(bdev_handle));
319         }
320
321         kfree(devname);
322         return bdev_handle;
323 }
324
325 static int
326 bl_parse_scsi(struct nfs_server *server, struct pnfs_block_dev *d,
327                 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
328 {
329         struct pnfs_block_volume *v = &volumes[idx];
330         struct bdev_handle *bdev_handle;
331         const struct pr_ops *ops;
332         int error;
333
334         if (!bl_validate_designator(v))
335                 return -EINVAL;
336
337         /*
338          * Try to open the RH/Fedora specific dm-mpath udev path first, as the
339          * wwn- links will only point to the first discovered SCSI device there.
340          * On other distributions like Debian, the default SCSI by-id path will
341          * point to the dm-multipath device if one exists.
342          */
343         bdev_handle = bl_open_path(v, "dm-uuid-mpath-0x");
344         if (IS_ERR(bdev_handle))
345                 bdev_handle = bl_open_path(v, "wwn-0x");
346         if (IS_ERR(bdev_handle))
347                 return PTR_ERR(bdev_handle);
348         d->bdev_handle = bdev_handle;
349
350         d->len = bdev_nr_bytes(d->bdev_handle->bdev);
351         d->map = bl_map_simple;
352         d->pr_key = v->scsi.pr_key;
353
354         pr_info("pNFS: using block device %s (reservation key 0x%llx)\n",
355                 d->bdev_handle->bdev->bd_disk->disk_name, d->pr_key);
356
357         ops = d->bdev_handle->bdev->bd_disk->fops->pr_ops;
358         if (!ops) {
359                 pr_err("pNFS: block device %s does not support reservations.",
360                                 d->bdev_handle->bdev->bd_disk->disk_name);
361                 error = -EINVAL;
362                 goto out_blkdev_put;
363         }
364
365         error = ops->pr_register(d->bdev_handle->bdev, 0, d->pr_key, true);
366         if (error) {
367                 pr_err("pNFS: failed to register key for block device %s.",
368                                 d->bdev_handle->bdev->bd_disk->disk_name);
369                 goto out_blkdev_put;
370         }
371
372         d->pr_registered = true;
373         return 0;
374
375 out_blkdev_put:
376         bdev_release(d->bdev_handle);
377         return error;
378 }
379
380 static int
381 bl_parse_slice(struct nfs_server *server, struct pnfs_block_dev *d,
382                 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
383 {
384         struct pnfs_block_volume *v = &volumes[idx];
385         int ret;
386
387         ret = bl_parse_deviceid(server, d, volumes, v->slice.volume, gfp_mask);
388         if (ret)
389                 return ret;
390
391         d->disk_offset = v->slice.start;
392         d->len = v->slice.len;
393         return 0;
394 }
395
396 static int
397 bl_parse_concat(struct nfs_server *server, struct pnfs_block_dev *d,
398                 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
399 {
400         struct pnfs_block_volume *v = &volumes[idx];
401         u64 len = 0;
402         int ret, i;
403
404         d->children = kcalloc(v->concat.volumes_count,
405                         sizeof(struct pnfs_block_dev), gfp_mask);
406         if (!d->children)
407                 return -ENOMEM;
408
409         for (i = 0; i < v->concat.volumes_count; i++) {
410                 ret = bl_parse_deviceid(server, &d->children[i],
411                                 volumes, v->concat.volumes[i], gfp_mask);
412                 if (ret)
413                         return ret;
414
415                 d->nr_children++;
416                 d->children[i].start += len;
417                 len += d->children[i].len;
418         }
419
420         d->len = len;
421         d->map = bl_map_concat;
422         return 0;
423 }
424
425 static int
426 bl_parse_stripe(struct nfs_server *server, struct pnfs_block_dev *d,
427                 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
428 {
429         struct pnfs_block_volume *v = &volumes[idx];
430         u64 len = 0;
431         int ret, i;
432
433         d->children = kcalloc(v->stripe.volumes_count,
434                         sizeof(struct pnfs_block_dev), gfp_mask);
435         if (!d->children)
436                 return -ENOMEM;
437
438         for (i = 0; i < v->stripe.volumes_count; i++) {
439                 ret = bl_parse_deviceid(server, &d->children[i],
440                                 volumes, v->stripe.volumes[i], gfp_mask);
441                 if (ret)
442                         return ret;
443
444                 d->nr_children++;
445                 len += d->children[i].len;
446         }
447
448         d->len = len;
449         d->chunk_size = v->stripe.chunk_size;
450         d->map = bl_map_stripe;
451         return 0;
452 }
453
454 static int
455 bl_parse_deviceid(struct nfs_server *server, struct pnfs_block_dev *d,
456                 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
457 {
458         switch (volumes[idx].type) {
459         case PNFS_BLOCK_VOLUME_SIMPLE:
460                 return bl_parse_simple(server, d, volumes, idx, gfp_mask);
461         case PNFS_BLOCK_VOLUME_SLICE:
462                 return bl_parse_slice(server, d, volumes, idx, gfp_mask);
463         case PNFS_BLOCK_VOLUME_CONCAT:
464                 return bl_parse_concat(server, d, volumes, idx, gfp_mask);
465         case PNFS_BLOCK_VOLUME_STRIPE:
466                 return bl_parse_stripe(server, d, volumes, idx, gfp_mask);
467         case PNFS_BLOCK_VOLUME_SCSI:
468                 return bl_parse_scsi(server, d, volumes, idx, gfp_mask);
469         default:
470                 dprintk("unsupported volume type: %d\n", volumes[idx].type);
471                 return -EIO;
472         }
473 }
474
475 struct nfs4_deviceid_node *
476 bl_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *pdev,
477                 gfp_t gfp_mask)
478 {
479         struct nfs4_deviceid_node *node = NULL;
480         struct pnfs_block_volume *volumes;
481         struct pnfs_block_dev *top;
482         struct xdr_stream xdr;
483         struct xdr_buf buf;
484         struct page *scratch;
485         int nr_volumes, ret, i;
486         __be32 *p;
487
488         scratch = alloc_page(gfp_mask);
489         if (!scratch)
490                 goto out;
491
492         xdr_init_decode_pages(&xdr, &buf, pdev->pages, pdev->pglen);
493         xdr_set_scratch_page(&xdr, scratch);
494
495         p = xdr_inline_decode(&xdr, sizeof(__be32));
496         if (!p)
497                 goto out_free_scratch;
498         nr_volumes = be32_to_cpup(p++);
499
500         volumes = kcalloc(nr_volumes, sizeof(struct pnfs_block_volume),
501                           gfp_mask);
502         if (!volumes)
503                 goto out_free_scratch;
504
505         for (i = 0; i < nr_volumes; i++) {
506                 ret = nfs4_block_decode_volume(&xdr, &volumes[i]);
507                 if (ret < 0)
508                         goto out_free_volumes;
509         }
510
511         top = kzalloc(sizeof(*top), gfp_mask);
512         if (!top)
513                 goto out_free_volumes;
514
515         ret = bl_parse_deviceid(server, top, volumes, nr_volumes - 1, gfp_mask);
516
517         node = &top->node;
518         nfs4_init_deviceid_node(node, server, &pdev->dev_id);
519         if (ret)
520                 nfs4_mark_deviceid_unavailable(node);
521
522 out_free_volumes:
523         kfree(volumes);
524 out_free_scratch:
525         __free_page(scratch);
526 out:
527         return node;
528 }