xref: /linux/fs/nfs/blocklayout/dev.c (revision ccc1ead23c3311be76e87d1b06620f6cb697b42a)
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 
bl_unregister_scsi(struct pnfs_block_dev * dev)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 
bl_register_scsi(struct pnfs_block_dev * dev)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 
bl_unregister_dev(struct pnfs_block_dev * dev)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 
bl_register_dev(struct pnfs_block_dev * dev)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
bl_free_device(struct pnfs_block_dev * dev)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
bl_free_deviceid_node(struct nfs4_deviceid_node * d)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
nfs4_block_decode_volume(struct xdr_stream * xdr,struct pnfs_block_volume * b)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 
bl_map_simple(struct pnfs_block_dev * dev,u64 offset,struct pnfs_block_dev_map * map)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 
bl_map_concat(struct pnfs_block_dev * dev,u64 offset,struct pnfs_block_dev_map * map)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 
bl_map_stripe(struct pnfs_block_dev * dev,u64 offset,struct pnfs_block_dev_map * map)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_chunk;
261 	u64 disk_offset;
262 
263 	chunk = div_u64(offset, dev->chunk_size);
264 	disk_chunk = div_u64_rem(chunk, dev->nr_children, &chunk_idx);
265 
266 	if (chunk_idx >= dev->nr_children) {
267 		dprintk("%s: invalid chunk idx %d (%lld/%lld)\n",
268 			__func__, chunk_idx, offset, dev->chunk_size);
269 		/* error, should not happen */
270 		return false;
271 	}
272 
273 	/* truncate offset to the beginning of the stripe */
274 	offset = chunk * dev->chunk_size;
275 
276 	/* disk offset of the stripe */
277 	disk_offset = disk_chunk * dev->chunk_size;
278 
279 	child = &dev->children[chunk_idx];
280 	child->map(child, disk_offset, map);
281 
282 	map->start += offset;
283 	map->disk_offset += disk_offset;
284 	map->len = dev->chunk_size;
285 	return true;
286 }
287 
288 static int
289 bl_parse_deviceid(struct nfs_server *server, struct pnfs_block_dev *d,
290 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask);
291 
292 
293 static int
bl_parse_simple(struct nfs_server * server,struct pnfs_block_dev * d,struct pnfs_block_volume * volumes,int idx,gfp_t gfp_mask)294 bl_parse_simple(struct nfs_server *server, struct pnfs_block_dev *d,
295 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
296 {
297 	struct pnfs_block_volume *v = &volumes[idx];
298 	struct file *bdev_file;
299 	dev_t dev;
300 
301 	dev = bl_resolve_deviceid(server, v, gfp_mask);
302 	if (!dev)
303 		return -EIO;
304 
305 	bdev_file = bdev_file_open_by_dev(dev, BLK_OPEN_READ | BLK_OPEN_WRITE,
306 				       NULL, NULL);
307 	if (IS_ERR(bdev_file)) {
308 		printk(KERN_WARNING "pNFS: failed to open device %d:%d (%ld)\n",
309 			MAJOR(dev), MINOR(dev), PTR_ERR(bdev_file));
310 		return PTR_ERR(bdev_file);
311 	}
312 	d->bdev_file = bdev_file;
313 	d->len = bdev_nr_bytes(file_bdev(bdev_file));
314 	d->map = bl_map_simple;
315 
316 	printk(KERN_INFO "pNFS: using block device %s\n",
317 		file_bdev(bdev_file)->bd_disk->disk_name);
318 	return 0;
319 }
320 
321 static bool
bl_validate_designator(struct pnfs_block_volume * v)322 bl_validate_designator(struct pnfs_block_volume *v)
323 {
324 	switch (v->scsi.designator_type) {
325 	case PS_DESIGNATOR_EUI64:
326 		if (v->scsi.code_set != PS_CODE_SET_BINARY)
327 			return false;
328 
329 		if (v->scsi.designator_len != 8 &&
330 		    v->scsi.designator_len != 10 &&
331 		    v->scsi.designator_len != 16)
332 			return false;
333 
334 		return true;
335 	case PS_DESIGNATOR_NAA:
336 		if (v->scsi.code_set != PS_CODE_SET_BINARY)
337 			return false;
338 
339 		if (v->scsi.designator_len != 8 &&
340 		    v->scsi.designator_len != 16)
341 			return false;
342 
343 		return true;
344 	case PS_DESIGNATOR_T10:
345 	case PS_DESIGNATOR_NAME:
346 		pr_err("pNFS: unsupported designator "
347 			"(code set %d, type %d, len %d.\n",
348 			v->scsi.code_set,
349 			v->scsi.designator_type,
350 			v->scsi.designator_len);
351 		return false;
352 	default:
353 		pr_err("pNFS: invalid designator "
354 			"(code set %d, type %d, len %d.\n",
355 			v->scsi.code_set,
356 			v->scsi.designator_type,
357 			v->scsi.designator_len);
358 		return false;
359 	}
360 }
361 
362 static struct file *
bl_open_path(struct pnfs_block_volume * v,const char * prefix)363 bl_open_path(struct pnfs_block_volume *v, const char *prefix)
364 {
365 	struct file *bdev_file;
366 	const char *devname;
367 
368 	devname = kasprintf(GFP_KERNEL, "/dev/disk/by-id/%s%*phN",
369 			prefix, v->scsi.designator_len, v->scsi.designator);
370 	if (!devname)
371 		return ERR_PTR(-ENOMEM);
372 
373 	bdev_file = bdev_file_open_by_path(devname, BLK_OPEN_READ | BLK_OPEN_WRITE,
374 					NULL, NULL);
375 	if (IS_ERR(bdev_file)) {
376 		dprintk("failed to open device %s (%ld)\n",
377 			devname, PTR_ERR(bdev_file));
378 	}
379 
380 	kfree(devname);
381 	return bdev_file;
382 }
383 
384 static int
bl_parse_scsi(struct nfs_server * server,struct pnfs_block_dev * d,struct pnfs_block_volume * volumes,int idx,gfp_t gfp_mask)385 bl_parse_scsi(struct nfs_server *server, struct pnfs_block_dev *d,
386 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
387 {
388 	struct pnfs_block_volume *v = &volumes[idx];
389 	struct block_device *bdev;
390 	const struct pr_ops *ops;
391 	struct file *bdev_file;
392 	int error;
393 
394 	if (!bl_validate_designator(v))
395 		return -EINVAL;
396 
397 	/*
398 	 * Try to open the RH/Fedora specific dm-mpath udev path first, as the
399 	 * wwn- links will only point to the first discovered SCSI device there.
400 	 * On other distributions like Debian, the default SCSI by-id path will
401 	 * point to the dm-multipath device if one exists.
402 	 */
403 	bdev_file = bl_open_path(v, "dm-uuid-mpath-0x");
404 	if (IS_ERR(bdev_file))
405 		bdev_file = bl_open_path(v, "wwn-0x");
406 	if (IS_ERR(bdev_file))
407 		bdev_file = bl_open_path(v, "nvme-eui.");
408 	if (IS_ERR(bdev_file)) {
409 		pr_warn("pNFS: no device found for volume %*phN\n",
410 			v->scsi.designator_len, v->scsi.designator);
411 		return PTR_ERR(bdev_file);
412 	}
413 	d->bdev_file = bdev_file;
414 	bdev = file_bdev(bdev_file);
415 
416 	d->len = bdev_nr_bytes(bdev);
417 	d->map = bl_map_simple;
418 	d->pr_key = v->scsi.pr_key;
419 
420 	if (d->len == 0)
421 		return -ENODEV;
422 
423 	ops = bdev->bd_disk->fops->pr_ops;
424 	if (!ops) {
425 		pr_err("pNFS: block device %s does not support reservations.",
426 				bdev->bd_disk->disk_name);
427 		error = -EINVAL;
428 		goto out_blkdev_put;
429 	}
430 
431 	return 0;
432 
433 out_blkdev_put:
434 	fput(d->bdev_file);
435 	return error;
436 }
437 
438 static int
bl_parse_slice(struct nfs_server * server,struct pnfs_block_dev * d,struct pnfs_block_volume * volumes,int idx,gfp_t gfp_mask)439 bl_parse_slice(struct nfs_server *server, struct pnfs_block_dev *d,
440 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
441 {
442 	struct pnfs_block_volume *v = &volumes[idx];
443 	int ret;
444 
445 	ret = bl_parse_deviceid(server, d, volumes, v->slice.volume, gfp_mask);
446 	if (ret)
447 		return ret;
448 
449 	d->disk_offset = v->slice.start;
450 	d->len = v->slice.len;
451 	return 0;
452 }
453 
454 static int
bl_parse_concat(struct nfs_server * server,struct pnfs_block_dev * d,struct pnfs_block_volume * volumes,int idx,gfp_t gfp_mask)455 bl_parse_concat(struct nfs_server *server, struct pnfs_block_dev *d,
456 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
457 {
458 	struct pnfs_block_volume *v = &volumes[idx];
459 	u64 len = 0;
460 	int ret, i;
461 
462 	d->children = kcalloc(v->concat.volumes_count,
463 			sizeof(struct pnfs_block_dev), gfp_mask);
464 	if (!d->children)
465 		return -ENOMEM;
466 
467 	for (i = 0; i < v->concat.volumes_count; i++) {
468 		ret = bl_parse_deviceid(server, &d->children[i],
469 				volumes, v->concat.volumes[i], gfp_mask);
470 		if (ret)
471 			return ret;
472 
473 		d->nr_children++;
474 		d->children[i].start += len;
475 		len += d->children[i].len;
476 	}
477 
478 	d->len = len;
479 	d->map = bl_map_concat;
480 	return 0;
481 }
482 
483 static int
bl_parse_stripe(struct nfs_server * server,struct pnfs_block_dev * d,struct pnfs_block_volume * volumes,int idx,gfp_t gfp_mask)484 bl_parse_stripe(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 	u64 len = 0;
489 	int ret, i;
490 
491 	d->children = kcalloc(v->stripe.volumes_count,
492 			sizeof(struct pnfs_block_dev), gfp_mask);
493 	if (!d->children)
494 		return -ENOMEM;
495 
496 	for (i = 0; i < v->stripe.volumes_count; i++) {
497 		ret = bl_parse_deviceid(server, &d->children[i],
498 				volumes, v->stripe.volumes[i], gfp_mask);
499 		if (ret)
500 			return ret;
501 
502 		d->nr_children++;
503 		len += d->children[i].len;
504 	}
505 
506 	d->len = len;
507 	d->chunk_size = v->stripe.chunk_size;
508 	d->map = bl_map_stripe;
509 	return 0;
510 }
511 
512 static int
bl_parse_deviceid(struct nfs_server * server,struct pnfs_block_dev * d,struct pnfs_block_volume * volumes,int idx,gfp_t gfp_mask)513 bl_parse_deviceid(struct nfs_server *server, struct pnfs_block_dev *d,
514 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
515 {
516 	d->type = volumes[idx].type;
517 
518 	switch (d->type) {
519 	case PNFS_BLOCK_VOLUME_SIMPLE:
520 		return bl_parse_simple(server, d, volumes, idx, gfp_mask);
521 	case PNFS_BLOCK_VOLUME_SLICE:
522 		return bl_parse_slice(server, d, volumes, idx, gfp_mask);
523 	case PNFS_BLOCK_VOLUME_CONCAT:
524 		return bl_parse_concat(server, d, volumes, idx, gfp_mask);
525 	case PNFS_BLOCK_VOLUME_STRIPE:
526 		return bl_parse_stripe(server, d, volumes, idx, gfp_mask);
527 	case PNFS_BLOCK_VOLUME_SCSI:
528 		return bl_parse_scsi(server, d, volumes, idx, gfp_mask);
529 	default:
530 		dprintk("unsupported volume type: %d\n", d->type);
531 		return -EIO;
532 	}
533 }
534 
535 struct nfs4_deviceid_node *
bl_alloc_deviceid_node(struct nfs_server * server,struct pnfs_device * pdev,gfp_t gfp_mask)536 bl_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *pdev,
537 		gfp_t gfp_mask)
538 {
539 	struct nfs4_deviceid_node *node = NULL;
540 	struct pnfs_block_volume *volumes;
541 	struct pnfs_block_dev *top;
542 	struct xdr_stream xdr;
543 	struct xdr_buf buf;
544 	struct page *scratch;
545 	int nr_volumes, ret, i;
546 	__be32 *p;
547 
548 	scratch = alloc_page(gfp_mask);
549 	if (!scratch)
550 		goto out;
551 
552 	xdr_init_decode_pages(&xdr, &buf, pdev->pages, pdev->pglen);
553 	xdr_set_scratch_page(&xdr, scratch);
554 
555 	p = xdr_inline_decode(&xdr, sizeof(__be32));
556 	if (!p)
557 		goto out_free_scratch;
558 	nr_volumes = be32_to_cpup(p++);
559 
560 	volumes = kcalloc(nr_volumes, sizeof(struct pnfs_block_volume),
561 			  gfp_mask);
562 	if (!volumes)
563 		goto out_free_scratch;
564 
565 	for (i = 0; i < nr_volumes; i++) {
566 		ret = nfs4_block_decode_volume(&xdr, &volumes[i]);
567 		if (ret < 0)
568 			goto out_free_volumes;
569 	}
570 
571 	top = kzalloc(sizeof(*top), gfp_mask);
572 	if (!top)
573 		goto out_free_volumes;
574 
575 	ret = bl_parse_deviceid(server, top, volumes, nr_volumes - 1, gfp_mask);
576 
577 	node = &top->node;
578 	nfs4_init_deviceid_node(node, server, &pdev->dev_id);
579 	if (ret)
580 		nfs4_mark_deviceid_unavailable(node);
581 
582 out_free_volumes:
583 	kfree(volumes);
584 out_free_scratch:
585 	__free_page(scratch);
586 out:
587 	return node;
588 }
589