xref: /linux/fs/nfs/blocklayout/dev.c (revision 65a83a613c4630232fb3e382229719df8558f7ae)
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/fs_struct.h>
8 #include <linux/nfs4.h>
9 #include <linux/nfs_fs.h>
10 #include <linux/nfs_xdr.h>
11 #include <linux/pr.h>
12 
13 #include "blocklayout.h"
14 #include "../nfs4trace.h"
15 
16 #define NFSDBG_FACILITY		NFSDBG_PNFS_LD
17 
18 #ifdef CONFIG_PNFS_SCSI_LAYOUT
19 static void bl_unregister_scsi(struct pnfs_block_dev *dev)
20 {
21 	struct block_device *bdev = file_bdev(dev->bdev_file);
22 	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
23 	int status;
24 
25 	status = ops->pr_register(bdev, dev->pr_key, 0, false);
26 	if (status)
27 		trace_bl_pr_key_unreg_err(bdev, dev->pr_key, status);
28 	else
29 		trace_bl_pr_key_unreg(bdev, dev->pr_key);
30 }
31 
32 static bool bl_register_scsi(struct pnfs_block_dev *dev)
33 {
34 	struct block_device *bdev = file_bdev(dev->bdev_file);
35 	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
36 	int status;
37 
38 	if (test_and_set_bit(PNFS_BDEV_REGISTERED, &dev->flags))
39 		return true;
40 
41 	status = ops->pr_register(bdev, 0, dev->pr_key, true);
42 	if (status) {
43 		trace_bl_pr_key_reg_err(bdev, dev->pr_key, status);
44 		return false;
45 	}
46 	trace_bl_pr_key_reg(bdev, dev->pr_key);
47 	return true;
48 }
49 #else
50 static void bl_unregister_scsi(struct pnfs_block_dev *dev)
51 {
52 }
53 
54 static bool bl_register_scsi(struct pnfs_block_dev *dev)
55 {
56 	return false;
57 }
58 #endif /* CONFIG_PNFS_SCSI_LAYOUT */
59 
60 static void bl_unregister_dev(struct pnfs_block_dev *dev)
61 {
62 	u32 i;
63 
64 	if (dev->nr_children) {
65 		for (i = 0; i < dev->nr_children; i++)
66 			bl_unregister_dev(&dev->children[i]);
67 		return;
68 	}
69 
70 	if (dev->type == PNFS_BLOCK_VOLUME_SCSI &&
71 		test_and_clear_bit(PNFS_BDEV_REGISTERED, &dev->flags))
72 		bl_unregister_scsi(dev);
73 }
74 
75 bool bl_register_dev(struct pnfs_block_dev *dev)
76 {
77 	u32 i;
78 
79 	if (dev->nr_children) {
80 		for (i = 0; i < dev->nr_children; i++) {
81 			if (!bl_register_dev(&dev->children[i])) {
82 				while (i > 0)
83 					bl_unregister_dev(&dev->children[--i]);
84 				return false;
85 			}
86 		}
87 		return true;
88 	}
89 
90 	if (dev->type == PNFS_BLOCK_VOLUME_SCSI)
91 		return bl_register_scsi(dev);
92 	return true;
93 }
94 
95 static void
96 bl_free_device(struct pnfs_block_dev *dev)
97 {
98 	bl_unregister_dev(dev);
99 
100 	if (dev->children) {
101 		int i;
102 
103 		for (i = 0; i < dev->nr_children; i++)
104 			bl_free_device(&dev->children[i]);
105 		kfree(dev->children);
106 		dev->children = NULL;
107 		dev->nr_children = 0;
108 	} else if (dev->bdev_file) {
109 		fput(dev->bdev_file);
110 		dev->bdev_file = NULL;
111 	}
112 }
113 
114 void
115 bl_free_deviceid_node(struct nfs4_deviceid_node *d)
116 {
117 	struct pnfs_block_dev *dev =
118 		container_of(d, struct pnfs_block_dev, node);
119 
120 	bl_free_device(dev);
121 	kfree_rcu(dev, node.rcu);
122 }
123 
124 static int
125 nfs4_block_decode_volume(struct xdr_stream *xdr, struct pnfs_block_volume *b)
126 {
127 	__be32 *p;
128 	int i;
129 
130 	p = xdr_inline_decode(xdr, 4);
131 	if (!p)
132 		return -EIO;
133 	b->type = be32_to_cpup(p++);
134 
135 	switch (b->type) {
136 	case PNFS_BLOCK_VOLUME_SIMPLE:
137 		p = xdr_inline_decode(xdr, 4);
138 		if (!p)
139 			return -EIO;
140 		b->simple.nr_sigs = be32_to_cpup(p++);
141 		if (!b->simple.nr_sigs || b->simple.nr_sigs > PNFS_BLOCK_MAX_UUIDS) {
142 			dprintk("Bad signature count: %d\n", b->simple.nr_sigs);
143 			return -EIO;
144 		}
145 
146 		b->simple.len = 4 + 4;
147 		for (i = 0; i < b->simple.nr_sigs; i++) {
148 			p = xdr_inline_decode(xdr, 8 + 4);
149 			if (!p)
150 				return -EIO;
151 			p = xdr_decode_hyper(p, &b->simple.sigs[i].offset);
152 			b->simple.sigs[i].sig_len = be32_to_cpup(p++);
153 			if (b->simple.sigs[i].sig_len > PNFS_BLOCK_UUID_LEN) {
154 				pr_info("signature too long: %d\n",
155 					b->simple.sigs[i].sig_len);
156 				return -EIO;
157 			}
158 
159 			p = xdr_inline_decode(xdr, b->simple.sigs[i].sig_len);
160 			if (!p)
161 				return -EIO;
162 			memcpy(&b->simple.sigs[i].sig, p,
163 				b->simple.sigs[i].sig_len);
164 
165 			b->simple.len += 8 + 4 + \
166 				(XDR_QUADLEN(b->simple.sigs[i].sig_len) << 2);
167 		}
168 		break;
169 	case PNFS_BLOCK_VOLUME_SLICE:
170 		p = xdr_inline_decode(xdr, 8 + 8 + 4);
171 		if (!p)
172 			return -EIO;
173 		p = xdr_decode_hyper(p, &b->slice.start);
174 		p = xdr_decode_hyper(p, &b->slice.len);
175 		b->slice.volume = be32_to_cpup(p++);
176 		break;
177 	case PNFS_BLOCK_VOLUME_CONCAT:
178 		p = xdr_inline_decode(xdr, 4);
179 		if (!p)
180 			return -EIO;
181 
182 		b->concat.volumes_count = be32_to_cpup(p++);
183 		if (b->concat.volumes_count > PNFS_BLOCK_MAX_DEVICES) {
184 			dprintk("Too many volumes: %d\n", b->concat.volumes_count);
185 			return -EIO;
186 		}
187 
188 		p = xdr_inline_decode(xdr, b->concat.volumes_count * 4);
189 		if (!p)
190 			return -EIO;
191 		for (i = 0; i < b->concat.volumes_count; i++)
192 			b->concat.volumes[i] = be32_to_cpup(p++);
193 		break;
194 	case PNFS_BLOCK_VOLUME_STRIPE:
195 		p = xdr_inline_decode(xdr, 8 + 4);
196 		if (!p)
197 			return -EIO;
198 
199 		p = xdr_decode_hyper(p, &b->stripe.chunk_size);
200 		b->stripe.volumes_count = be32_to_cpup(p++);
201 		if (b->stripe.volumes_count > PNFS_BLOCK_MAX_DEVICES) {
202 			dprintk("Too many volumes: %d\n", b->stripe.volumes_count);
203 			return -EIO;
204 		}
205 
206 		p = xdr_inline_decode(xdr, b->stripe.volumes_count * 4);
207 		if (!p)
208 			return -EIO;
209 		for (i = 0; i < b->stripe.volumes_count; i++)
210 			b->stripe.volumes[i] = be32_to_cpup(p++);
211 		break;
212 	case PNFS_BLOCK_VOLUME_SCSI:
213 		p = xdr_inline_decode(xdr, 4 + 4 + 4);
214 		if (!p)
215 			return -EIO;
216 		b->scsi.code_set = be32_to_cpup(p++);
217 		b->scsi.designator_type = be32_to_cpup(p++);
218 		b->scsi.designator_len = be32_to_cpup(p++);
219 		p = xdr_inline_decode(xdr, b->scsi.designator_len);
220 		if (!p)
221 			return -EIO;
222 		if (b->scsi.designator_len > 256)
223 			return -EIO;
224 		memcpy(&b->scsi.designator, p, b->scsi.designator_len);
225 		p = xdr_inline_decode(xdr, 8);
226 		if (!p)
227 			return -EIO;
228 		p = xdr_decode_hyper(p, &b->scsi.pr_key);
229 		break;
230 	default:
231 		dprintk("unknown volume type!\n");
232 		return -EIO;
233 	}
234 
235 	return 0;
236 }
237 
238 static bool bl_map_simple(struct pnfs_block_dev *dev, u64 offset,
239 		struct pnfs_block_dev_map *map)
240 {
241 	map->start = dev->start;
242 	map->len = dev->len;
243 	map->disk_offset = dev->disk_offset;
244 	map->bdev = file_bdev(dev->bdev_file);
245 	return true;
246 }
247 
248 static bool bl_map_concat(struct pnfs_block_dev *dev, u64 offset,
249 		struct pnfs_block_dev_map *map)
250 {
251 	int i;
252 
253 	for (i = 0; i < dev->nr_children; i++) {
254 		struct pnfs_block_dev *child = &dev->children[i];
255 
256 		if (child->start > offset ||
257 		    child->start + child->len <= offset)
258 			continue;
259 
260 		child->map(child, offset - child->start, map);
261 		return true;
262 	}
263 
264 	dprintk("%s: ran off loop!\n", __func__);
265 	return false;
266 }
267 
268 static bool bl_map_stripe(struct pnfs_block_dev *dev, u64 offset,
269 		struct pnfs_block_dev_map *map)
270 {
271 	struct pnfs_block_dev *child;
272 	u64 chunk;
273 	u32 chunk_idx;
274 	u64 disk_chunk;
275 	u64 disk_offset;
276 
277 	chunk = div_u64(offset, dev->chunk_size);
278 	disk_chunk = div_u64_rem(chunk, dev->nr_children, &chunk_idx);
279 
280 	if (chunk_idx >= dev->nr_children) {
281 		dprintk("%s: invalid chunk idx %d (%lld/%lld)\n",
282 			__func__, chunk_idx, offset, dev->chunk_size);
283 		/* error, should not happen */
284 		return false;
285 	}
286 
287 	/* truncate offset to the beginning of the stripe */
288 	offset = chunk * dev->chunk_size;
289 
290 	/* disk offset of the stripe */
291 	disk_offset = disk_chunk * dev->chunk_size;
292 
293 	child = &dev->children[chunk_idx];
294 	child->map(child, disk_offset, map);
295 
296 	map->start += offset;
297 	map->disk_offset += disk_offset;
298 	map->len = dev->chunk_size;
299 	return true;
300 }
301 
302 static int
303 bl_parse_deviceid(struct nfs_server *server, struct pnfs_block_dev *d,
304 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask);
305 
306 #ifdef CONFIG_PNFS_BLOCK_LAYOUT
307 static int
308 bl_parse_simple(struct nfs_server *server, struct pnfs_block_dev *d,
309 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
310 {
311 	struct pnfs_block_volume *v = &volumes[idx];
312 	struct file *bdev_file;
313 	dev_t dev;
314 
315 	dev = bl_resolve_deviceid(server, v, gfp_mask);
316 	if (!dev)
317 		return -EIO;
318 
319 	bdev_file = bdev_file_open_by_dev(dev, BLK_OPEN_READ | BLK_OPEN_WRITE,
320 				       NULL, NULL);
321 	if (IS_ERR(bdev_file)) {
322 		printk(KERN_WARNING "pNFS: failed to open device %d:%d (%ld)\n",
323 			MAJOR(dev), MINOR(dev), PTR_ERR(bdev_file));
324 		return PTR_ERR(bdev_file);
325 	}
326 	d->bdev_file = bdev_file;
327 	d->len = bdev_nr_bytes(file_bdev(bdev_file));
328 	d->map = bl_map_simple;
329 
330 	printk(KERN_INFO "pNFS: using block device %s\n",
331 		file_bdev(bdev_file)->bd_disk->disk_name);
332 	return 0;
333 }
334 #else
335 static int
336 bl_parse_simple(struct nfs_server *server, struct pnfs_block_dev *d,
337                 struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
338 {
339 	dprintk("unsupported volume type: %d\n", PNFS_BLOCK_VOLUME_SIMPLE);
340 	return -EIO;
341 }
342 #endif /* CONFIG_PNFS_BLOCK_LAYOUT */
343 
344 #ifdef CONFIG_PNFS_SCSI_LAYOUT
345 static bool
346 bl_validate_designator(struct pnfs_block_volume *v)
347 {
348 	switch (v->scsi.designator_type) {
349 	case PS_DESIGNATOR_EUI64:
350 		if (v->scsi.code_set != PS_CODE_SET_BINARY)
351 			return false;
352 
353 		if (v->scsi.designator_len != 8 &&
354 		    v->scsi.designator_len != 10 &&
355 		    v->scsi.designator_len != 16)
356 			return false;
357 
358 		return true;
359 	case PS_DESIGNATOR_NAA:
360 		if (v->scsi.code_set != PS_CODE_SET_BINARY)
361 			return false;
362 
363 		if (v->scsi.designator_len != 8 &&
364 		    v->scsi.designator_len != 16)
365 			return false;
366 
367 		return true;
368 	case PS_DESIGNATOR_T10:
369 	case PS_DESIGNATOR_NAME:
370 		pr_err("pNFS: unsupported designator "
371 			"(code set %d, type %d, len %d.\n",
372 			v->scsi.code_set,
373 			v->scsi.designator_type,
374 			v->scsi.designator_len);
375 		return false;
376 	default:
377 		pr_err("pNFS: invalid designator "
378 			"(code set %d, type %d, len %d.\n",
379 			v->scsi.code_set,
380 			v->scsi.designator_type,
381 			v->scsi.designator_len);
382 		return false;
383 	}
384 }
385 
386 static struct file *
387 bl_open_path(struct pnfs_block_volume *v, const char *prefix)
388 {
389 	struct file *bdev_file;
390 	const char *devname __free(kfree) = NULL;
391 
392 	devname = kasprintf(GFP_KERNEL, "/dev/disk/by-id/%s%*phN",
393 			prefix, v->scsi.designator_len, v->scsi.designator);
394 	if (!devname)
395 		return ERR_PTR(-ENOMEM);
396 
397 	if (tsk_is_kthread(current)) {
398 		scoped_with_init_fs()
399 			bdev_file = bdev_file_open_by_path(devname,
400 					BLK_OPEN_READ | BLK_OPEN_WRITE,
401 					NULL, NULL);
402 	} else {
403 		bdev_file = bdev_file_open_by_path(devname,
404 				BLK_OPEN_READ | BLK_OPEN_WRITE, NULL, NULL);
405 	}
406 	if (IS_ERR(bdev_file)) {
407 		dprintk("failed to open device %s (%ld)\n",
408 			devname, PTR_ERR(bdev_file));
409 	} else {
410 		pr_info("pNFS: using block device %s\n",
411 			file_bdev(bdev_file)->bd_disk->disk_name);
412 	}
413 
414 	return bdev_file;
415 }
416 
417 static int
418 bl_parse_scsi(struct nfs_server *server, struct pnfs_block_dev *d,
419 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
420 {
421 	struct pnfs_block_volume *v = &volumes[idx];
422 	struct block_device *bdev;
423 	const struct pr_ops *ops;
424 	struct file *bdev_file;
425 	int error;
426 
427 	if (!bl_validate_designator(v))
428 		return -EINVAL;
429 
430 	/*
431 	 * Try to open the RH/Fedora specific dm-mpath udev path first, as the
432 	 * wwn- links will only point to the first discovered SCSI device there.
433 	 * On other distributions like Debian, the default SCSI by-id path will
434 	 * point to the dm-multipath device if one exists.
435 	 */
436 	bdev_file = bl_open_path(v, "dm-uuid-mpath-0x");
437 	if (IS_ERR(bdev_file))
438 		bdev_file = bl_open_path(v, "wwn-0x");
439 	if (IS_ERR(bdev_file))
440 		bdev_file = bl_open_path(v, "nvme-eui.");
441 	if (IS_ERR(bdev_file)) {
442 		pr_warn("pNFS: no device found for volume %*phN\n",
443 			v->scsi.designator_len, v->scsi.designator);
444 		return PTR_ERR(bdev_file);
445 	}
446 	d->bdev_file = bdev_file;
447 	bdev = file_bdev(bdev_file);
448 
449 	d->len = bdev_nr_bytes(bdev);
450 	d->map = bl_map_simple;
451 	d->pr_key = v->scsi.pr_key;
452 
453 	if (d->len == 0) {
454 		error = -ENODEV;
455 		goto out_blkdev_put;
456 	}
457 
458 	ops = bdev->bd_disk->fops->pr_ops;
459 	if (!ops) {
460 		pr_err("pNFS: block device %s does not support reservations.",
461 				bdev->bd_disk->disk_name);
462 		error = -EINVAL;
463 		goto out_blkdev_put;
464 	}
465 
466 	return 0;
467 
468 out_blkdev_put:
469 	fput(d->bdev_file);
470 	d->bdev_file = NULL;
471 	return error;
472 }
473 #else
474 static int
475 bl_parse_scsi(struct nfs_server *server, struct pnfs_block_dev *d,
476 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
477 {
478 	dprintk("unsupported volume type: %d\n", PNFS_BLOCK_VOLUME_SCSI);
479 	return -EIO;
480 }
481 #endif /* CONFIG_PNFS_SCSI_LAYOUT */
482 
483 static int
484 bl_parse_slice(struct nfs_server *server, struct pnfs_block_dev *d,
485 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
486 {
487 	struct pnfs_block_volume *v = &volumes[idx];
488 	int ret;
489 
490 	ret = bl_parse_deviceid(server, d, volumes, v->slice.volume, gfp_mask);
491 	if (ret)
492 		return ret;
493 
494 	d->disk_offset = v->slice.start;
495 	d->len = v->slice.len;
496 	return 0;
497 }
498 
499 static int
500 bl_parse_concat(struct nfs_server *server, struct pnfs_block_dev *d,
501 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
502 {
503 	struct pnfs_block_volume *v = &volumes[idx];
504 	u64 len = 0;
505 	int ret, i;
506 
507 	d->children = kzalloc_objs(struct pnfs_block_dev,
508 				   v->concat.volumes_count, gfp_mask);
509 	if (!d->children)
510 		return -ENOMEM;
511 
512 	for (i = 0; i < v->concat.volumes_count; i++) {
513 		ret = bl_parse_deviceid(server, &d->children[i],
514 				volumes, v->concat.volumes[i], gfp_mask);
515 		if (ret) {
516 			bl_free_device(&d->children[i]);
517 			bl_free_device(d);
518 			return ret;
519 		}
520 
521 		d->nr_children++;
522 		d->children[i].start += len;
523 		len += d->children[i].len;
524 	}
525 
526 	d->len = len;
527 	d->map = bl_map_concat;
528 	return 0;
529 }
530 
531 static int
532 bl_parse_stripe(struct nfs_server *server, struct pnfs_block_dev *d,
533 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
534 {
535 	struct pnfs_block_volume *v = &volumes[idx];
536 	u64 len = 0;
537 	int ret, i;
538 
539 	d->children = kzalloc_objs(struct pnfs_block_dev,
540 				   v->stripe.volumes_count, gfp_mask);
541 	if (!d->children)
542 		return -ENOMEM;
543 
544 	for (i = 0; i < v->stripe.volumes_count; i++) {
545 		ret = bl_parse_deviceid(server, &d->children[i],
546 				volumes, v->stripe.volumes[i], gfp_mask);
547 		if (ret) {
548 			bl_free_device(&d->children[i]);
549 			bl_free_device(d);
550 			return ret;
551 		}
552 
553 		d->nr_children++;
554 		len += d->children[i].len;
555 	}
556 
557 	d->len = len;
558 	d->chunk_size = v->stripe.chunk_size;
559 	d->map = bl_map_stripe;
560 	return 0;
561 }
562 
563 static int
564 bl_parse_deviceid(struct nfs_server *server, struct pnfs_block_dev *d,
565 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
566 {
567 	d->type = volumes[idx].type;
568 
569 	switch (d->type) {
570 	case PNFS_BLOCK_VOLUME_SIMPLE:
571 		return bl_parse_simple(server, d, volumes, idx, gfp_mask);
572 	case PNFS_BLOCK_VOLUME_SLICE:
573 		return bl_parse_slice(server, d, volumes, idx, gfp_mask);
574 	case PNFS_BLOCK_VOLUME_CONCAT:
575 		return bl_parse_concat(server, d, volumes, idx, gfp_mask);
576 	case PNFS_BLOCK_VOLUME_STRIPE:
577 		return bl_parse_stripe(server, d, volumes, idx, gfp_mask);
578 	case PNFS_BLOCK_VOLUME_SCSI:
579 		return bl_parse_scsi(server, d, volumes, idx, gfp_mask);
580 	default:
581 		dprintk("unsupported volume type: %d\n", d->type);
582 		return -EIO;
583 	}
584 }
585 
586 struct nfs4_deviceid_node *
587 bl_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *pdev,
588 		gfp_t gfp_mask)
589 {
590 	struct nfs4_deviceid_node *node = NULL;
591 	struct pnfs_block_volume *volumes;
592 	struct pnfs_block_dev *top;
593 	struct xdr_stream xdr;
594 	struct xdr_buf buf;
595 	struct folio *scratch;
596 	int nr_volumes, ret, i;
597 	__be32 *p;
598 
599 	scratch = folio_alloc(gfp_mask, 0);
600 	if (!scratch)
601 		goto out;
602 
603 	xdr_init_decode_pages(&xdr, &buf, pdev->pages, pdev->pglen);
604 	xdr_set_scratch_folio(&xdr, scratch);
605 
606 	p = xdr_inline_decode(&xdr, sizeof(__be32));
607 	if (!p)
608 		goto out_free_scratch;
609 	nr_volumes = be32_to_cpup(p++);
610 
611 	volumes = kzalloc_objs(struct pnfs_block_volume, nr_volumes, gfp_mask);
612 	if (!volumes)
613 		goto out_free_scratch;
614 
615 	for (i = 0; i < nr_volumes; i++) {
616 		ret = nfs4_block_decode_volume(&xdr, &volumes[i]);
617 		if (ret < 0)
618 			goto out_free_volumes;
619 	}
620 
621 	top = kzalloc_obj(*top, gfp_mask);
622 	if (!top)
623 		goto out_free_volumes;
624 
625 	ret = bl_parse_deviceid(server, top, volumes, nr_volumes - 1, gfp_mask);
626 
627 	node = &top->node;
628 	nfs4_init_deviceid_node(node, server, &pdev->dev_id);
629 	if (ret)
630 		nfs4_mark_deviceid_unavailable(node);
631 
632 out_free_volumes:
633 	kfree(volumes);
634 out_free_scratch:
635 	folio_put(scratch);
636 out:
637 	return node;
638 }
639