xref: /openbmc/linux/fs/nfs/blocklayout/dev.c (revision 7587eb18)
1 /*
2  * Copyright (c) 2014-2016 Christoph Hellwig.
3  */
4 #include <linux/sunrpc/svc.h>
5 #include <linux/blkdev.h>
6 #include <linux/nfs4.h>
7 #include <linux/nfs_fs.h>
8 #include <linux/nfs_xdr.h>
9 #include <linux/pr.h>
10 
11 #include "blocklayout.h"
12 
13 #define NFSDBG_FACILITY		NFSDBG_PNFS_LD
14 
15 static void
16 bl_free_device(struct pnfs_block_dev *dev)
17 {
18 	if (dev->nr_children) {
19 		int i;
20 
21 		for (i = 0; i < dev->nr_children; i++)
22 			bl_free_device(&dev->children[i]);
23 		kfree(dev->children);
24 	} else {
25 		if (dev->pr_registered) {
26 			const struct pr_ops *ops =
27 				dev->bdev->bd_disk->fops->pr_ops;
28 			int error;
29 
30 			error = ops->pr_register(dev->bdev, dev->pr_key, 0,
31 				false);
32 			if (error)
33 				pr_err("failed to unregister PR key.\n");
34 		}
35 
36 		if (dev->bdev)
37 			blkdev_put(dev->bdev, FMODE_READ | FMODE_WRITE);
38 	}
39 }
40 
41 void
42 bl_free_deviceid_node(struct nfs4_deviceid_node *d)
43 {
44 	struct pnfs_block_dev *dev =
45 		container_of(d, struct pnfs_block_dev, node);
46 
47 	bl_free_device(dev);
48 	kfree_rcu(dev, node.rcu);
49 }
50 
51 static int
52 nfs4_block_decode_volume(struct xdr_stream *xdr, struct pnfs_block_volume *b)
53 {
54 	__be32 *p;
55 	int i;
56 
57 	p = xdr_inline_decode(xdr, 4);
58 	if (!p)
59 		return -EIO;
60 	b->type = be32_to_cpup(p++);
61 
62 	switch (b->type) {
63 	case PNFS_BLOCK_VOLUME_SIMPLE:
64 		p = xdr_inline_decode(xdr, 4);
65 		if (!p)
66 			return -EIO;
67 		b->simple.nr_sigs = be32_to_cpup(p++);
68 		if (!b->simple.nr_sigs) {
69 			dprintk("no signature\n");
70 			return -EIO;
71 		}
72 
73 		b->simple.len = 4 + 4;
74 		for (i = 0; i < b->simple.nr_sigs; i++) {
75 			p = xdr_inline_decode(xdr, 8 + 4);
76 			if (!p)
77 				return -EIO;
78 			p = xdr_decode_hyper(p, &b->simple.sigs[i].offset);
79 			b->simple.sigs[i].sig_len = be32_to_cpup(p++);
80 			if (b->simple.sigs[i].sig_len > PNFS_BLOCK_UUID_LEN) {
81 				pr_info("signature too long: %d\n",
82 					b->simple.sigs[i].sig_len);
83 				return -EIO;
84 			}
85 
86 			p = xdr_inline_decode(xdr, b->simple.sigs[i].sig_len);
87 			if (!p)
88 				return -EIO;
89 			memcpy(&b->simple.sigs[i].sig, p,
90 				b->simple.sigs[i].sig_len);
91 
92 			b->simple.len += 8 + 4 + b->simple.sigs[i].sig_len;
93 		}
94 		break;
95 	case PNFS_BLOCK_VOLUME_SLICE:
96 		p = xdr_inline_decode(xdr, 8 + 8 + 4);
97 		if (!p)
98 			return -EIO;
99 		p = xdr_decode_hyper(p, &b->slice.start);
100 		p = xdr_decode_hyper(p, &b->slice.len);
101 		b->slice.volume = be32_to_cpup(p++);
102 		break;
103 	case PNFS_BLOCK_VOLUME_CONCAT:
104 		p = xdr_inline_decode(xdr, 4);
105 		if (!p)
106 			return -EIO;
107 		b->concat.volumes_count = be32_to_cpup(p++);
108 
109 		p = xdr_inline_decode(xdr, b->concat.volumes_count * 4);
110 		if (!p)
111 			return -EIO;
112 		for (i = 0; i < b->concat.volumes_count; i++)
113 			b->concat.volumes[i] = be32_to_cpup(p++);
114 		break;
115 	case PNFS_BLOCK_VOLUME_STRIPE:
116 		p = xdr_inline_decode(xdr, 8 + 4);
117 		if (!p)
118 			return -EIO;
119 		p = xdr_decode_hyper(p, &b->stripe.chunk_size);
120 		b->stripe.volumes_count = be32_to_cpup(p++);
121 
122 		p = xdr_inline_decode(xdr, b->stripe.volumes_count * 4);
123 		if (!p)
124 			return -EIO;
125 		for (i = 0; i < b->stripe.volumes_count; i++)
126 			b->stripe.volumes[i] = be32_to_cpup(p++);
127 		break;
128 	case PNFS_BLOCK_VOLUME_SCSI:
129 		p = xdr_inline_decode(xdr, 4 + 4 + 4);
130 		if (!p)
131 			return -EIO;
132 		b->scsi.code_set = be32_to_cpup(p++);
133 		b->scsi.designator_type = be32_to_cpup(p++);
134 		b->scsi.designator_len = be32_to_cpup(p++);
135 		p = xdr_inline_decode(xdr, b->scsi.designator_len);
136 		if (!p)
137 			return -EIO;
138 		if (b->scsi.designator_len > 256)
139 			return -EIO;
140 		memcpy(&b->scsi.designator, p, b->scsi.designator_len);
141 		p = xdr_inline_decode(xdr, 8);
142 		if (!p)
143 			return -EIO;
144 		p = xdr_decode_hyper(p, &b->scsi.pr_key);
145 		break;
146 	default:
147 		dprintk("unknown volume type!\n");
148 		return -EIO;
149 	}
150 
151 	return 0;
152 }
153 
154 static bool bl_map_simple(struct pnfs_block_dev *dev, u64 offset,
155 		struct pnfs_block_dev_map *map)
156 {
157 	map->start = dev->start;
158 	map->len = dev->len;
159 	map->disk_offset = dev->disk_offset;
160 	map->bdev = dev->bdev;
161 	return true;
162 }
163 
164 static bool bl_map_concat(struct pnfs_block_dev *dev, u64 offset,
165 		struct pnfs_block_dev_map *map)
166 {
167 	int i;
168 
169 	for (i = 0; i < dev->nr_children; i++) {
170 		struct pnfs_block_dev *child = &dev->children[i];
171 
172 		if (child->start > offset ||
173 		    child->start + child->len <= offset)
174 			continue;
175 
176 		child->map(child, offset - child->start, map);
177 		return true;
178 	}
179 
180 	dprintk("%s: ran off loop!\n", __func__);
181 	return false;
182 }
183 
184 static bool bl_map_stripe(struct pnfs_block_dev *dev, u64 offset,
185 		struct pnfs_block_dev_map *map)
186 {
187 	struct pnfs_block_dev *child;
188 	u64 chunk;
189 	u32 chunk_idx;
190 	u64 disk_offset;
191 
192 	chunk = div_u64(offset, dev->chunk_size);
193 	div_u64_rem(chunk, dev->nr_children, &chunk_idx);
194 
195 	if (chunk_idx > dev->nr_children) {
196 		dprintk("%s: invalid chunk idx %d (%lld/%lld)\n",
197 			__func__, chunk_idx, offset, dev->chunk_size);
198 		/* error, should not happen */
199 		return false;
200 	}
201 
202 	/* truncate offset to the beginning of the stripe */
203 	offset = chunk * dev->chunk_size;
204 
205 	/* disk offset of the stripe */
206 	disk_offset = div_u64(offset, dev->nr_children);
207 
208 	child = &dev->children[chunk_idx];
209 	child->map(child, disk_offset, map);
210 
211 	map->start += offset;
212 	map->disk_offset += disk_offset;
213 	map->len = dev->chunk_size;
214 	return true;
215 }
216 
217 static int
218 bl_parse_deviceid(struct nfs_server *server, struct pnfs_block_dev *d,
219 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask);
220 
221 
222 static int
223 bl_parse_simple(struct nfs_server *server, struct pnfs_block_dev *d,
224 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
225 {
226 	struct pnfs_block_volume *v = &volumes[idx];
227 	dev_t dev;
228 
229 	dev = bl_resolve_deviceid(server, v, gfp_mask);
230 	if (!dev)
231 		return -EIO;
232 
233 	d->bdev = blkdev_get_by_dev(dev, FMODE_READ | FMODE_WRITE, NULL);
234 	if (IS_ERR(d->bdev)) {
235 		printk(KERN_WARNING "pNFS: failed to open device %d:%d (%ld)\n",
236 			MAJOR(dev), MINOR(dev), PTR_ERR(d->bdev));
237 		return PTR_ERR(d->bdev);
238 	}
239 
240 
241 	d->len = i_size_read(d->bdev->bd_inode);
242 	d->map = bl_map_simple;
243 
244 	printk(KERN_INFO "pNFS: using block device %s\n",
245 		d->bdev->bd_disk->disk_name);
246 	return 0;
247 }
248 
249 static bool
250 bl_validate_designator(struct pnfs_block_volume *v)
251 {
252 	switch (v->scsi.designator_type) {
253 	case PS_DESIGNATOR_EUI64:
254 		if (v->scsi.code_set != PS_CODE_SET_BINARY)
255 			return false;
256 
257 		if (v->scsi.designator_len != 8 &&
258 		    v->scsi.designator_len != 10 &&
259 		    v->scsi.designator_len != 16)
260 			return false;
261 
262 		return true;
263 	case PS_DESIGNATOR_NAA:
264 		if (v->scsi.code_set != PS_CODE_SET_BINARY)
265 			return false;
266 
267 		if (v->scsi.designator_len != 8 &&
268 		    v->scsi.designator_len != 16)
269 			return false;
270 
271 		return true;
272 	case PS_DESIGNATOR_T10:
273 	case PS_DESIGNATOR_NAME:
274 		pr_err("pNFS: unsupported designator "
275 			"(code set %d, type %d, len %d.\n",
276 			v->scsi.code_set,
277 			v->scsi.designator_type,
278 			v->scsi.designator_len);
279 		return false;
280 	default:
281 		pr_err("pNFS: invalid designator "
282 			"(code set %d, type %d, len %d.\n",
283 			v->scsi.code_set,
284 			v->scsi.designator_type,
285 			v->scsi.designator_len);
286 		return false;
287 	}
288 }
289 
290 static int
291 bl_parse_scsi(struct nfs_server *server, struct pnfs_block_dev *d,
292 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
293 {
294 	struct pnfs_block_volume *v = &volumes[idx];
295 	const struct pr_ops *ops;
296 	const char *devname;
297 	int error;
298 
299 	if (!bl_validate_designator(v))
300 		return -EINVAL;
301 
302 	switch (v->scsi.designator_len) {
303 	case 8:
304 		devname = kasprintf(GFP_KERNEL, "/dev/disk/by-id/wwn-0x%8phN",
305 				v->scsi.designator);
306 		break;
307 	case 12:
308 		devname = kasprintf(GFP_KERNEL, "/dev/disk/by-id/wwn-0x%12phN",
309 				v->scsi.designator);
310 		break;
311 	case 16:
312 		devname = kasprintf(GFP_KERNEL, "/dev/disk/by-id/wwn-0x%16phN",
313 				v->scsi.designator);
314 		break;
315 	default:
316 		return -EINVAL;
317 	}
318 
319 	d->bdev = blkdev_get_by_path(devname, FMODE_READ, NULL);
320 	if (IS_ERR(d->bdev)) {
321 		pr_warn("pNFS: failed to open device %s (%ld)\n",
322 			devname, PTR_ERR(d->bdev));
323 		kfree(devname);
324 		return PTR_ERR(d->bdev);
325 	}
326 
327 	kfree(devname);
328 
329 	d->len = i_size_read(d->bdev->bd_inode);
330 	d->map = bl_map_simple;
331 	d->pr_key = v->scsi.pr_key;
332 
333 	pr_info("pNFS: using block device %s (reservation key 0x%llx)\n",
334 		d->bdev->bd_disk->disk_name, d->pr_key);
335 
336 	ops = d->bdev->bd_disk->fops->pr_ops;
337 	if (!ops) {
338 		pr_err("pNFS: block device %s does not support reservations.",
339 				d->bdev->bd_disk->disk_name);
340 		error = -EINVAL;
341 		goto out_blkdev_put;
342 	}
343 
344 	error = ops->pr_register(d->bdev, 0, d->pr_key, true);
345 	if (error) {
346 		pr_err("pNFS: failed to register key for block device %s.",
347 				d->bdev->bd_disk->disk_name);
348 		goto out_blkdev_put;
349 	}
350 
351 	d->pr_registered = true;
352 	return 0;
353 
354 out_blkdev_put:
355 	blkdev_put(d->bdev, FMODE_READ);
356 	return error;
357 }
358 
359 static int
360 bl_parse_slice(struct nfs_server *server, struct pnfs_block_dev *d,
361 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
362 {
363 	struct pnfs_block_volume *v = &volumes[idx];
364 	int ret;
365 
366 	ret = bl_parse_deviceid(server, d, volumes, v->slice.volume, gfp_mask);
367 	if (ret)
368 		return ret;
369 
370 	d->disk_offset = v->slice.start;
371 	d->len = v->slice.len;
372 	return 0;
373 }
374 
375 static int
376 bl_parse_concat(struct nfs_server *server, struct pnfs_block_dev *d,
377 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
378 {
379 	struct pnfs_block_volume *v = &volumes[idx];
380 	u64 len = 0;
381 	int ret, i;
382 
383 	d->children = kcalloc(v->concat.volumes_count,
384 			sizeof(struct pnfs_block_dev), GFP_KERNEL);
385 	if (!d->children)
386 		return -ENOMEM;
387 
388 	for (i = 0; i < v->concat.volumes_count; i++) {
389 		ret = bl_parse_deviceid(server, &d->children[i],
390 				volumes, v->concat.volumes[i], gfp_mask);
391 		if (ret)
392 			return ret;
393 
394 		d->nr_children++;
395 		d->children[i].start += len;
396 		len += d->children[i].len;
397 	}
398 
399 	d->len = len;
400 	d->map = bl_map_concat;
401 	return 0;
402 }
403 
404 static int
405 bl_parse_stripe(struct nfs_server *server, struct pnfs_block_dev *d,
406 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
407 {
408 	struct pnfs_block_volume *v = &volumes[idx];
409 	u64 len = 0;
410 	int ret, i;
411 
412 	d->children = kcalloc(v->stripe.volumes_count,
413 			sizeof(struct pnfs_block_dev), GFP_KERNEL);
414 	if (!d->children)
415 		return -ENOMEM;
416 
417 	for (i = 0; i < v->stripe.volumes_count; i++) {
418 		ret = bl_parse_deviceid(server, &d->children[i],
419 				volumes, v->stripe.volumes[i], gfp_mask);
420 		if (ret)
421 			return ret;
422 
423 		d->nr_children++;
424 		len += d->children[i].len;
425 	}
426 
427 	d->len = len;
428 	d->chunk_size = v->stripe.chunk_size;
429 	d->map = bl_map_stripe;
430 	return 0;
431 }
432 
433 static int
434 bl_parse_deviceid(struct nfs_server *server, struct pnfs_block_dev *d,
435 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
436 {
437 	switch (volumes[idx].type) {
438 	case PNFS_BLOCK_VOLUME_SIMPLE:
439 		return bl_parse_simple(server, d, volumes, idx, gfp_mask);
440 	case PNFS_BLOCK_VOLUME_SLICE:
441 		return bl_parse_slice(server, d, volumes, idx, gfp_mask);
442 	case PNFS_BLOCK_VOLUME_CONCAT:
443 		return bl_parse_concat(server, d, volumes, idx, gfp_mask);
444 	case PNFS_BLOCK_VOLUME_STRIPE:
445 		return bl_parse_stripe(server, d, volumes, idx, gfp_mask);
446 	case PNFS_BLOCK_VOLUME_SCSI:
447 		return bl_parse_scsi(server, d, volumes, idx, gfp_mask);
448 	default:
449 		dprintk("unsupported volume type: %d\n", volumes[idx].type);
450 		return -EIO;
451 	}
452 }
453 
454 struct nfs4_deviceid_node *
455 bl_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *pdev,
456 		gfp_t gfp_mask)
457 {
458 	struct nfs4_deviceid_node *node = NULL;
459 	struct pnfs_block_volume *volumes;
460 	struct pnfs_block_dev *top;
461 	struct xdr_stream xdr;
462 	struct xdr_buf buf;
463 	struct page *scratch;
464 	int nr_volumes, ret, i;
465 	__be32 *p;
466 
467 	scratch = alloc_page(gfp_mask);
468 	if (!scratch)
469 		goto out;
470 
471 	xdr_init_decode_pages(&xdr, &buf, pdev->pages, pdev->pglen);
472 	xdr_set_scratch_buffer(&xdr, page_address(scratch), PAGE_SIZE);
473 
474 	p = xdr_inline_decode(&xdr, sizeof(__be32));
475 	if (!p)
476 		goto out_free_scratch;
477 	nr_volumes = be32_to_cpup(p++);
478 
479 	volumes = kcalloc(nr_volumes, sizeof(struct pnfs_block_volume),
480 			  gfp_mask);
481 	if (!volumes)
482 		goto out_free_scratch;
483 
484 	for (i = 0; i < nr_volumes; i++) {
485 		ret = nfs4_block_decode_volume(&xdr, &volumes[i]);
486 		if (ret < 0)
487 			goto out_free_volumes;
488 	}
489 
490 	top = kzalloc(sizeof(*top), gfp_mask);
491 	if (!top)
492 		goto out_free_volumes;
493 
494 	ret = bl_parse_deviceid(server, top, volumes, nr_volumes - 1, gfp_mask);
495 	if (ret) {
496 		bl_free_device(top);
497 		kfree(top);
498 		goto out_free_volumes;
499 	}
500 
501 	node = &top->node;
502 	nfs4_init_deviceid_node(node, server, &pdev->dev_id);
503 
504 out_free_volumes:
505 	kfree(volumes);
506 out_free_scratch:
507 	__free_page(scratch);
508 out:
509 	return node;
510 }
511