xref: /linux/fs/nfs/blocklayout/dev.c (revision e7d759f31ca295d589f7420719c311870bb3166f) 
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 	if (d->len == 0)
355 		return -ENODEV;
356 
357 	pr_info("pNFS: using block device %s (reservation key 0x%llx)\n",
358 		d->bdev_handle->bdev->bd_disk->disk_name, d->pr_key);
359 
360 	ops = d->bdev_handle->bdev->bd_disk->fops->pr_ops;
361 	if (!ops) {
362 		pr_err("pNFS: block device %s does not support reservations.",
363 				d->bdev_handle->bdev->bd_disk->disk_name);
364 		error = -EINVAL;
365 		goto out_blkdev_put;
366 	}
367 
368 	error = ops->pr_register(d->bdev_handle->bdev, 0, d->pr_key, true);
369 	if (error) {
370 		pr_err("pNFS: failed to register key for block device %s.",
371 				d->bdev_handle->bdev->bd_disk->disk_name);
372 		goto out_blkdev_put;
373 	}
374 
375 	d->pr_registered = true;
376 	return 0;
377 
378 out_blkdev_put:
379 	bdev_release(d->bdev_handle);
380 	return error;
381 }
382 
383 static int
384 bl_parse_slice(struct nfs_server *server, struct pnfs_block_dev *d,
385 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
386 {
387 	struct pnfs_block_volume *v = &volumes[idx];
388 	int ret;
389 
390 	ret = bl_parse_deviceid(server, d, volumes, v->slice.volume, gfp_mask);
391 	if (ret)
392 		return ret;
393 
394 	d->disk_offset = v->slice.start;
395 	d->len = v->slice.len;
396 	return 0;
397 }
398 
399 static int
400 bl_parse_concat(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 	u64 len = 0;
405 	int ret, i;
406 
407 	d->children = kcalloc(v->concat.volumes_count,
408 			sizeof(struct pnfs_block_dev), gfp_mask);
409 	if (!d->children)
410 		return -ENOMEM;
411 
412 	for (i = 0; i < v->concat.volumes_count; i++) {
413 		ret = bl_parse_deviceid(server, &d->children[i],
414 				volumes, v->concat.volumes[i], gfp_mask);
415 		if (ret)
416 			return ret;
417 
418 		d->nr_children++;
419 		d->children[i].start += len;
420 		len += d->children[i].len;
421 	}
422 
423 	d->len = len;
424 	d->map = bl_map_concat;
425 	return 0;
426 }
427 
428 static int
429 bl_parse_stripe(struct nfs_server *server, struct pnfs_block_dev *d,
430 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
431 {
432 	struct pnfs_block_volume *v = &volumes[idx];
433 	u64 len = 0;
434 	int ret, i;
435 
436 	d->children = kcalloc(v->stripe.volumes_count,
437 			sizeof(struct pnfs_block_dev), gfp_mask);
438 	if (!d->children)
439 		return -ENOMEM;
440 
441 	for (i = 0; i < v->stripe.volumes_count; i++) {
442 		ret = bl_parse_deviceid(server, &d->children[i],
443 				volumes, v->stripe.volumes[i], gfp_mask);
444 		if (ret)
445 			return ret;
446 
447 		d->nr_children++;
448 		len += d->children[i].len;
449 	}
450 
451 	d->len = len;
452 	d->chunk_size = v->stripe.chunk_size;
453 	d->map = bl_map_stripe;
454 	return 0;
455 }
456 
457 static int
458 bl_parse_deviceid(struct nfs_server *server, struct pnfs_block_dev *d,
459 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
460 {
461 	switch (volumes[idx].type) {
462 	case PNFS_BLOCK_VOLUME_SIMPLE:
463 		return bl_parse_simple(server, d, volumes, idx, gfp_mask);
464 	case PNFS_BLOCK_VOLUME_SLICE:
465 		return bl_parse_slice(server, d, volumes, idx, gfp_mask);
466 	case PNFS_BLOCK_VOLUME_CONCAT:
467 		return bl_parse_concat(server, d, volumes, idx, gfp_mask);
468 	case PNFS_BLOCK_VOLUME_STRIPE:
469 		return bl_parse_stripe(server, d, volumes, idx, gfp_mask);
470 	case PNFS_BLOCK_VOLUME_SCSI:
471 		return bl_parse_scsi(server, d, volumes, idx, gfp_mask);
472 	default:
473 		dprintk("unsupported volume type: %d\n", volumes[idx].type);
474 		return -EIO;
475 	}
476 }
477 
478 struct nfs4_deviceid_node *
479 bl_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *pdev,
480 		gfp_t gfp_mask)
481 {
482 	struct nfs4_deviceid_node *node = NULL;
483 	struct pnfs_block_volume *volumes;
484 	struct pnfs_block_dev *top;
485 	struct xdr_stream xdr;
486 	struct xdr_buf buf;
487 	struct page *scratch;
488 	int nr_volumes, ret, i;
489 	__be32 *p;
490 
491 	scratch = alloc_page(gfp_mask);
492 	if (!scratch)
493 		goto out;
494 
495 	xdr_init_decode_pages(&xdr, &buf, pdev->pages, pdev->pglen);
496 	xdr_set_scratch_page(&xdr, scratch);
497 
498 	p = xdr_inline_decode(&xdr, sizeof(__be32));
499 	if (!p)
500 		goto out_free_scratch;
501 	nr_volumes = be32_to_cpup(p++);
502 
503 	volumes = kcalloc(nr_volumes, sizeof(struct pnfs_block_volume),
504 			  gfp_mask);
505 	if (!volumes)
506 		goto out_free_scratch;
507 
508 	for (i = 0; i < nr_volumes; i++) {
509 		ret = nfs4_block_decode_volume(&xdr, &volumes[i]);
510 		if (ret < 0)
511 			goto out_free_volumes;
512 	}
513 
514 	top = kzalloc(sizeof(*top), gfp_mask);
515 	if (!top)
516 		goto out_free_volumes;
517 
518 	ret = bl_parse_deviceid(server, top, volumes, nr_volumes - 1, gfp_mask);
519 
520 	node = &top->node;
521 	nfs4_init_deviceid_node(node, server, &pdev->dev_id);
522 	if (ret)
523 		nfs4_mark_deviceid_unavailable(node);
524 
525 out_free_volumes:
526 	kfree(volumes);
527 out_free_scratch:
528 	__free_page(scratch);
529 out:
530 	return node;
531 }
532