xref: /linux/fs/nfs/blocklayout/dev.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
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 #include "../nfs4trace.h"
14 
15 #define NFSDBG_FACILITY		NFSDBG_PNFS_LD
16 
17 static void bl_unregister_scsi(struct pnfs_block_dev *dev)
18 {
19 	struct block_device *bdev = file_bdev(dev->bdev_file);
20 	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
21 	int status;
22 
23 	status = ops->pr_register(bdev, dev->pr_key, 0, false);
24 	if (status)
25 		trace_bl_pr_key_unreg_err(bdev, dev->pr_key, status);
26 	else
27 		trace_bl_pr_key_unreg(bdev, dev->pr_key);
28 }
29 
30 static bool bl_register_scsi(struct pnfs_block_dev *dev)
31 {
32 	struct block_device *bdev = file_bdev(dev->bdev_file);
33 	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
34 	int status;
35 
36 	if (test_and_set_bit(PNFS_BDEV_REGISTERED, &dev->flags))
37 		return true;
38 
39 	status = ops->pr_register(bdev, 0, dev->pr_key, true);
40 	if (status) {
41 		trace_bl_pr_key_reg_err(bdev, dev->pr_key, status);
42 		return false;
43 	}
44 	trace_bl_pr_key_reg(bdev, dev->pr_key);
45 	return true;
46 }
47 
48 static void bl_unregister_dev(struct pnfs_block_dev *dev)
49 {
50 	u32 i;
51 
52 	if (dev->nr_children) {
53 		for (i = 0; i < dev->nr_children; i++)
54 			bl_unregister_dev(&dev->children[i]);
55 		return;
56 	}
57 
58 	if (dev->type == PNFS_BLOCK_VOLUME_SCSI &&
59 		test_and_clear_bit(PNFS_BDEV_REGISTERED, &dev->flags))
60 		bl_unregister_scsi(dev);
61 }
62 
63 bool bl_register_dev(struct pnfs_block_dev *dev)
64 {
65 	u32 i;
66 
67 	if (dev->nr_children) {
68 		for (i = 0; i < dev->nr_children; i++) {
69 			if (!bl_register_dev(&dev->children[i])) {
70 				while (i > 0)
71 					bl_unregister_dev(&dev->children[--i]);
72 				return false;
73 			}
74 		}
75 		return true;
76 	}
77 
78 	if (dev->type == PNFS_BLOCK_VOLUME_SCSI)
79 		return bl_register_scsi(dev);
80 	return true;
81 }
82 
83 static void
84 bl_free_device(struct pnfs_block_dev *dev)
85 {
86 	bl_unregister_dev(dev);
87 
88 	if (dev->nr_children) {
89 		int i;
90 
91 		for (i = 0; i < dev->nr_children; i++)
92 			bl_free_device(&dev->children[i]);
93 		kfree(dev->children);
94 	} else {
95 		if (dev->bdev_file)
96 			fput(dev->bdev_file);
97 	}
98 }
99 
100 void
101 bl_free_deviceid_node(struct nfs4_deviceid_node *d)
102 {
103 	struct pnfs_block_dev *dev =
104 		container_of(d, struct pnfs_block_dev, node);
105 
106 	bl_free_device(dev);
107 	kfree_rcu(dev, node.rcu);
108 }
109 
110 static int
111 nfs4_block_decode_volume(struct xdr_stream *xdr, struct pnfs_block_volume *b)
112 {
113 	__be32 *p;
114 	int i;
115 
116 	p = xdr_inline_decode(xdr, 4);
117 	if (!p)
118 		return -EIO;
119 	b->type = be32_to_cpup(p++);
120 
121 	switch (b->type) {
122 	case PNFS_BLOCK_VOLUME_SIMPLE:
123 		p = xdr_inline_decode(xdr, 4);
124 		if (!p)
125 			return -EIO;
126 		b->simple.nr_sigs = be32_to_cpup(p++);
127 		if (!b->simple.nr_sigs || b->simple.nr_sigs > PNFS_BLOCK_MAX_UUIDS) {
128 			dprintk("Bad signature count: %d\n", b->simple.nr_sigs);
129 			return -EIO;
130 		}
131 
132 		b->simple.len = 4 + 4;
133 		for (i = 0; i < b->simple.nr_sigs; i++) {
134 			p = xdr_inline_decode(xdr, 8 + 4);
135 			if (!p)
136 				return -EIO;
137 			p = xdr_decode_hyper(p, &b->simple.sigs[i].offset);
138 			b->simple.sigs[i].sig_len = be32_to_cpup(p++);
139 			if (b->simple.sigs[i].sig_len > PNFS_BLOCK_UUID_LEN) {
140 				pr_info("signature too long: %d\n",
141 					b->simple.sigs[i].sig_len);
142 				return -EIO;
143 			}
144 
145 			p = xdr_inline_decode(xdr, b->simple.sigs[i].sig_len);
146 			if (!p)
147 				return -EIO;
148 			memcpy(&b->simple.sigs[i].sig, p,
149 				b->simple.sigs[i].sig_len);
150 
151 			b->simple.len += 8 + 4 + \
152 				(XDR_QUADLEN(b->simple.sigs[i].sig_len) << 2);
153 		}
154 		break;
155 	case PNFS_BLOCK_VOLUME_SLICE:
156 		p = xdr_inline_decode(xdr, 8 + 8 + 4);
157 		if (!p)
158 			return -EIO;
159 		p = xdr_decode_hyper(p, &b->slice.start);
160 		p = xdr_decode_hyper(p, &b->slice.len);
161 		b->slice.volume = be32_to_cpup(p++);
162 		break;
163 	case PNFS_BLOCK_VOLUME_CONCAT:
164 		p = xdr_inline_decode(xdr, 4);
165 		if (!p)
166 			return -EIO;
167 
168 		b->concat.volumes_count = be32_to_cpup(p++);
169 		if (b->concat.volumes_count > PNFS_BLOCK_MAX_DEVICES) {
170 			dprintk("Too many volumes: %d\n", b->concat.volumes_count);
171 			return -EIO;
172 		}
173 
174 		p = xdr_inline_decode(xdr, b->concat.volumes_count * 4);
175 		if (!p)
176 			return -EIO;
177 		for (i = 0; i < b->concat.volumes_count; i++)
178 			b->concat.volumes[i] = be32_to_cpup(p++);
179 		break;
180 	case PNFS_BLOCK_VOLUME_STRIPE:
181 		p = xdr_inline_decode(xdr, 8 + 4);
182 		if (!p)
183 			return -EIO;
184 
185 		p = xdr_decode_hyper(p, &b->stripe.chunk_size);
186 		b->stripe.volumes_count = be32_to_cpup(p++);
187 		if (b->stripe.volumes_count > PNFS_BLOCK_MAX_DEVICES) {
188 			dprintk("Too many volumes: %d\n", b->stripe.volumes_count);
189 			return -EIO;
190 		}
191 
192 		p = xdr_inline_decode(xdr, b->stripe.volumes_count * 4);
193 		if (!p)
194 			return -EIO;
195 		for (i = 0; i < b->stripe.volumes_count; i++)
196 			b->stripe.volumes[i] = be32_to_cpup(p++);
197 		break;
198 	case PNFS_BLOCK_VOLUME_SCSI:
199 		p = xdr_inline_decode(xdr, 4 + 4 + 4);
200 		if (!p)
201 			return -EIO;
202 		b->scsi.code_set = be32_to_cpup(p++);
203 		b->scsi.designator_type = be32_to_cpup(p++);
204 		b->scsi.designator_len = be32_to_cpup(p++);
205 		p = xdr_inline_decode(xdr, b->scsi.designator_len);
206 		if (!p)
207 			return -EIO;
208 		if (b->scsi.designator_len > 256)
209 			return -EIO;
210 		memcpy(&b->scsi.designator, p, b->scsi.designator_len);
211 		p = xdr_inline_decode(xdr, 8);
212 		if (!p)
213 			return -EIO;
214 		p = xdr_decode_hyper(p, &b->scsi.pr_key);
215 		break;
216 	default:
217 		dprintk("unknown volume type!\n");
218 		return -EIO;
219 	}
220 
221 	return 0;
222 }
223 
224 static bool bl_map_simple(struct pnfs_block_dev *dev, u64 offset,
225 		struct pnfs_block_dev_map *map)
226 {
227 	map->start = dev->start;
228 	map->len = dev->len;
229 	map->disk_offset = dev->disk_offset;
230 	map->bdev = file_bdev(dev->bdev_file);
231 	return true;
232 }
233 
234 static bool bl_map_concat(struct pnfs_block_dev *dev, u64 offset,
235 		struct pnfs_block_dev_map *map)
236 {
237 	int i;
238 
239 	for (i = 0; i < dev->nr_children; i++) {
240 		struct pnfs_block_dev *child = &dev->children[i];
241 
242 		if (child->start > offset ||
243 		    child->start + child->len <= offset)
244 			continue;
245 
246 		child->map(child, offset - child->start, map);
247 		return true;
248 	}
249 
250 	dprintk("%s: ran off loop!\n", __func__);
251 	return false;
252 }
253 
254 static bool bl_map_stripe(struct pnfs_block_dev *dev, u64 offset,
255 		struct pnfs_block_dev_map *map)
256 {
257 	struct pnfs_block_dev *child;
258 	u64 chunk;
259 	u32 chunk_idx;
260 	u64 disk_offset;
261 
262 	chunk = div_u64(offset, dev->chunk_size);
263 	div_u64_rem(chunk, dev->nr_children, &chunk_idx);
264 
265 	if (chunk_idx >= dev->nr_children) {
266 		dprintk("%s: invalid chunk idx %d (%lld/%lld)\n",
267 			__func__, chunk_idx, offset, dev->chunk_size);
268 		/* error, should not happen */
269 		return false;
270 	}
271 
272 	/* truncate offset to the beginning of the stripe */
273 	offset = chunk * dev->chunk_size;
274 
275 	/* disk offset of the stripe */
276 	disk_offset = div_u64(offset, dev->nr_children);
277 
278 	child = &dev->children[chunk_idx];
279 	child->map(child, disk_offset, map);
280 
281 	map->start += offset;
282 	map->disk_offset += disk_offset;
283 	map->len = dev->chunk_size;
284 	return true;
285 }
286 
287 static int
288 bl_parse_deviceid(struct nfs_server *server, struct pnfs_block_dev *d,
289 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask);
290 
291 
292 static int
293 bl_parse_simple(struct nfs_server *server, struct pnfs_block_dev *d,
294 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
295 {
296 	struct pnfs_block_volume *v = &volumes[idx];
297 	struct file *bdev_file;
298 	dev_t dev;
299 
300 	dev = bl_resolve_deviceid(server, v, gfp_mask);
301 	if (!dev)
302 		return -EIO;
303 
304 	bdev_file = bdev_file_open_by_dev(dev, BLK_OPEN_READ | BLK_OPEN_WRITE,
305 				       NULL, NULL);
306 	if (IS_ERR(bdev_file)) {
307 		printk(KERN_WARNING "pNFS: failed to open device %d:%d (%ld)\n",
308 			MAJOR(dev), MINOR(dev), PTR_ERR(bdev_file));
309 		return PTR_ERR(bdev_file);
310 	}
311 	d->bdev_file = bdev_file;
312 	d->len = bdev_nr_bytes(file_bdev(bdev_file));
313 	d->map = bl_map_simple;
314 
315 	printk(KERN_INFO "pNFS: using block device %s\n",
316 		file_bdev(bdev_file)->bd_disk->disk_name);
317 	return 0;
318 }
319 
320 static bool
321 bl_validate_designator(struct pnfs_block_volume *v)
322 {
323 	switch (v->scsi.designator_type) {
324 	case PS_DESIGNATOR_EUI64:
325 		if (v->scsi.code_set != PS_CODE_SET_BINARY)
326 			return false;
327 
328 		if (v->scsi.designator_len != 8 &&
329 		    v->scsi.designator_len != 10 &&
330 		    v->scsi.designator_len != 16)
331 			return false;
332 
333 		return true;
334 	case PS_DESIGNATOR_NAA:
335 		if (v->scsi.code_set != PS_CODE_SET_BINARY)
336 			return false;
337 
338 		if (v->scsi.designator_len != 8 &&
339 		    v->scsi.designator_len != 16)
340 			return false;
341 
342 		return true;
343 	case PS_DESIGNATOR_T10:
344 	case PS_DESIGNATOR_NAME:
345 		pr_err("pNFS: unsupported designator "
346 			"(code set %d, type %d, len %d.\n",
347 			v->scsi.code_set,
348 			v->scsi.designator_type,
349 			v->scsi.designator_len);
350 		return false;
351 	default:
352 		pr_err("pNFS: invalid designator "
353 			"(code set %d, type %d, len %d.\n",
354 			v->scsi.code_set,
355 			v->scsi.designator_type,
356 			v->scsi.designator_len);
357 		return false;
358 	}
359 }
360 
361 static struct file *
362 bl_open_path(struct pnfs_block_volume *v, const char *prefix)
363 {
364 	struct file *bdev_file;
365 	const char *devname;
366 
367 	devname = kasprintf(GFP_KERNEL, "/dev/disk/by-id/%s%*phN",
368 			prefix, v->scsi.designator_len, v->scsi.designator);
369 	if (!devname)
370 		return ERR_PTR(-ENOMEM);
371 
372 	bdev_file = bdev_file_open_by_path(devname, BLK_OPEN_READ | BLK_OPEN_WRITE,
373 					NULL, NULL);
374 	if (IS_ERR(bdev_file)) {
375 		dprintk("failed to open device %s (%ld)\n",
376 			devname, PTR_ERR(bdev_file));
377 	}
378 
379 	kfree(devname);
380 	return bdev_file;
381 }
382 
383 static int
384 bl_parse_scsi(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 	struct block_device *bdev;
389 	const struct pr_ops *ops;
390 	struct file *bdev_file;
391 	int error;
392 
393 	if (!bl_validate_designator(v))
394 		return -EINVAL;
395 
396 	/*
397 	 * Try to open the RH/Fedora specific dm-mpath udev path first, as the
398 	 * wwn- links will only point to the first discovered SCSI device there.
399 	 * On other distributions like Debian, the default SCSI by-id path will
400 	 * point to the dm-multipath device if one exists.
401 	 */
402 	bdev_file = bl_open_path(v, "dm-uuid-mpath-0x");
403 	if (IS_ERR(bdev_file))
404 		bdev_file = bl_open_path(v, "wwn-0x");
405 	if (IS_ERR(bdev_file))
406 		bdev_file = bl_open_path(v, "nvme-eui.");
407 	if (IS_ERR(bdev_file)) {
408 		pr_warn("pNFS: no device found for volume %*phN\n",
409 			v->scsi.designator_len, v->scsi.designator);
410 		return PTR_ERR(bdev_file);
411 	}
412 	d->bdev_file = bdev_file;
413 	bdev = file_bdev(bdev_file);
414 
415 	d->len = bdev_nr_bytes(bdev);
416 	d->map = bl_map_simple;
417 	d->pr_key = v->scsi.pr_key;
418 
419 	if (d->len == 0)
420 		return -ENODEV;
421 
422 	ops = bdev->bd_disk->fops->pr_ops;
423 	if (!ops) {
424 		pr_err("pNFS: block device %s does not support reservations.",
425 				bdev->bd_disk->disk_name);
426 		error = -EINVAL;
427 		goto out_blkdev_put;
428 	}
429 
430 	return 0;
431 
432 out_blkdev_put:
433 	fput(d->bdev_file);
434 	return error;
435 }
436 
437 static int
438 bl_parse_slice(struct nfs_server *server, struct pnfs_block_dev *d,
439 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
440 {
441 	struct pnfs_block_volume *v = &volumes[idx];
442 	int ret;
443 
444 	ret = bl_parse_deviceid(server, d, volumes, v->slice.volume, gfp_mask);
445 	if (ret)
446 		return ret;
447 
448 	d->disk_offset = v->slice.start;
449 	d->len = v->slice.len;
450 	return 0;
451 }
452 
453 static int
454 bl_parse_concat(struct nfs_server *server, struct pnfs_block_dev *d,
455 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
456 {
457 	struct pnfs_block_volume *v = &volumes[idx];
458 	u64 len = 0;
459 	int ret, i;
460 
461 	d->children = kcalloc(v->concat.volumes_count,
462 			sizeof(struct pnfs_block_dev), gfp_mask);
463 	if (!d->children)
464 		return -ENOMEM;
465 
466 	for (i = 0; i < v->concat.volumes_count; i++) {
467 		ret = bl_parse_deviceid(server, &d->children[i],
468 				volumes, v->concat.volumes[i], gfp_mask);
469 		if (ret)
470 			return ret;
471 
472 		d->nr_children++;
473 		d->children[i].start += len;
474 		len += d->children[i].len;
475 	}
476 
477 	d->len = len;
478 	d->map = bl_map_concat;
479 	return 0;
480 }
481 
482 static int
483 bl_parse_stripe(struct nfs_server *server, struct pnfs_block_dev *d,
484 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
485 {
486 	struct pnfs_block_volume *v = &volumes[idx];
487 	u64 len = 0;
488 	int ret, i;
489 
490 	d->children = kcalloc(v->stripe.volumes_count,
491 			sizeof(struct pnfs_block_dev), gfp_mask);
492 	if (!d->children)
493 		return -ENOMEM;
494 
495 	for (i = 0; i < v->stripe.volumes_count; i++) {
496 		ret = bl_parse_deviceid(server, &d->children[i],
497 				volumes, v->stripe.volumes[i], gfp_mask);
498 		if (ret)
499 			return ret;
500 
501 		d->nr_children++;
502 		len += d->children[i].len;
503 	}
504 
505 	d->len = len;
506 	d->chunk_size = v->stripe.chunk_size;
507 	d->map = bl_map_stripe;
508 	return 0;
509 }
510 
511 static int
512 bl_parse_deviceid(struct nfs_server *server, struct pnfs_block_dev *d,
513 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
514 {
515 	d->type = volumes[idx].type;
516 
517 	switch (d->type) {
518 	case PNFS_BLOCK_VOLUME_SIMPLE:
519 		return bl_parse_simple(server, d, volumes, idx, gfp_mask);
520 	case PNFS_BLOCK_VOLUME_SLICE:
521 		return bl_parse_slice(server, d, volumes, idx, gfp_mask);
522 	case PNFS_BLOCK_VOLUME_CONCAT:
523 		return bl_parse_concat(server, d, volumes, idx, gfp_mask);
524 	case PNFS_BLOCK_VOLUME_STRIPE:
525 		return bl_parse_stripe(server, d, volumes, idx, gfp_mask);
526 	case PNFS_BLOCK_VOLUME_SCSI:
527 		return bl_parse_scsi(server, d, volumes, idx, gfp_mask);
528 	default:
529 		dprintk("unsupported volume type: %d\n", d->type);
530 		return -EIO;
531 	}
532 }
533 
534 struct nfs4_deviceid_node *
535 bl_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *pdev,
536 		gfp_t gfp_mask)
537 {
538 	struct nfs4_deviceid_node *node = NULL;
539 	struct pnfs_block_volume *volumes;
540 	struct pnfs_block_dev *top;
541 	struct xdr_stream xdr;
542 	struct xdr_buf buf;
543 	struct page *scratch;
544 	int nr_volumes, ret, i;
545 	__be32 *p;
546 
547 	scratch = alloc_page(gfp_mask);
548 	if (!scratch)
549 		goto out;
550 
551 	xdr_init_decode_pages(&xdr, &buf, pdev->pages, pdev->pglen);
552 	xdr_set_scratch_page(&xdr, scratch);
553 
554 	p = xdr_inline_decode(&xdr, sizeof(__be32));
555 	if (!p)
556 		goto out_free_scratch;
557 	nr_volumes = be32_to_cpup(p++);
558 
559 	volumes = kcalloc(nr_volumes, sizeof(struct pnfs_block_volume),
560 			  gfp_mask);
561 	if (!volumes)
562 		goto out_free_scratch;
563 
564 	for (i = 0; i < nr_volumes; i++) {
565 		ret = nfs4_block_decode_volume(&xdr, &volumes[i]);
566 		if (ret < 0)
567 			goto out_free_volumes;
568 	}
569 
570 	top = kzalloc(sizeof(*top), gfp_mask);
571 	if (!top)
572 		goto out_free_volumes;
573 
574 	ret = bl_parse_deviceid(server, top, volumes, nr_volumes - 1, gfp_mask);
575 
576 	node = &top->node;
577 	nfs4_init_deviceid_node(node, server, &pdev->dev_id);
578 	if (ret)
579 		nfs4_mark_deviceid_unavailable(node);
580 
581 out_free_volumes:
582 	kfree(volumes);
583 out_free_scratch:
584 	__free_page(scratch);
585 out:
586 	return node;
587 }
588