summaryrefslogtreecommitdiffstats
path: root/block/blk-zoned.c
blob: acb7252c7e81ed3cd0df2e069c15cb3d24d63a23 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
/*
 * Zoned block device handling
 *
 * Copyright (c) 2015, Hannes Reinecke
 * Copyright (c) 2015, SUSE Linux GmbH
 *
 * Copyright (c) 2016, Damien Le Moal
 * Copyright (c) 2016, Western Digital
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/rbtree.h>
#include <linux/blkdev.h>

static inline sector_t blk_zone_start(struct request_queue *q,
				      sector_t sector)
{
	sector_t zone_mask = blk_queue_zone_sectors(q) - 1;

	return sector & ~zone_mask;
}

/*
 * Return true if a request is a write requests that needs zone write locking.
 */
bool blk_req_needs_zone_write_lock(struct request *rq)
{
	if (!rq->q->seq_zones_wlock)
		return false;

	if (blk_rq_is_passthrough(rq))
		return false;

	switch (req_op(rq)) {
	case REQ_OP_WRITE_ZEROES:
	case REQ_OP_WRITE_SAME:
	case REQ_OP_WRITE:
		return blk_rq_zone_is_seq(rq);
	default:
		return false;
	}
}
EXPORT_SYMBOL_GPL(blk_req_needs_zone_write_lock);

void __blk_req_zone_write_lock(struct request *rq)
{
	if (WARN_ON_ONCE(test_and_set_bit(blk_rq_zone_no(rq),
					  rq->q->seq_zones_wlock)))
		return;

	WARN_ON_ONCE(rq->rq_flags & RQF_ZONE_WRITE_LOCKED);
	rq->rq_flags |= RQF_ZONE_WRITE_LOCKED;
}
EXPORT_SYMBOL_GPL(__blk_req_zone_write_lock);

void __blk_req_zone_write_unlock(struct request *rq)
{
	rq->rq_flags &= ~RQF_ZONE_WRITE_LOCKED;
	if (rq->q->seq_zones_wlock)
		WARN_ON_ONCE(!test_and_clear_bit(blk_rq_zone_no(rq),
						 rq->q->seq_zones_wlock));
}
EXPORT_SYMBOL_GPL(__blk_req_zone_write_unlock);

/*
 * Check that a zone report belongs to the partition.
 * If yes, fix its start sector and write pointer, copy it in the
 * zone information array and return true. Return false otherwise.
 */
static bool blkdev_report_zone(struct block_device *bdev,
			       struct blk_zone *rep,
			       struct blk_zone *zone)
{
	sector_t offset = get_start_sect(bdev);

	if (rep->start < offset)
		return false;

	rep->start -= offset;
	if (rep->start + rep->len > bdev->bd_part->nr_sects)
		return false;

	if (rep->type == BLK_ZONE_TYPE_CONVENTIONAL)
		rep->wp = rep->start + rep->len;
	else
		rep->wp -= offset;
	memcpy(zone, rep, sizeof(struct blk_zone));

	return true;
}

/**
 * blkdev_report_zones - Get zones information
 * @bdev:	Target block device
 * @sector:	Sector from which to report zones
 * @zones:	Array of zone structures where to return the zones information
 * @nr_zones:	Number of zone structures in the zone array
 * @gfp_mask:	Memory allocation flags (for bio_alloc)
 *
 * Description:
 *    Get zone information starting from the zone containing @sector.
 *    The number of zone information reported may be less than the number
 *    requested by @nr_zones. The number of zones actually reported is
 *    returned in @nr_zones.
 */
int blkdev_report_zones(struct block_device *bdev,
			sector_t sector,
			struct blk_zone *zones,
			unsigned int *nr_zones,
			gfp_t gfp_mask)
{
	struct request_queue *q = bdev_get_queue(bdev);
	struct blk_zone_report_hdr *hdr;
	unsigned int nrz = *nr_zones;
	struct page *page;
	unsigned int nr_rep;
	size_t rep_bytes;
	unsigned int nr_pages;
	struct bio *bio;
	struct bio_vec *bv;
	unsigned int i, n, nz;
	unsigned int ofst;
	void *addr;
	int ret;

	if (!q)
		return -ENXIO;

	if (!blk_queue_is_zoned(q))
		return -EOPNOTSUPP;

	if (!nrz)
		return 0;

	if (sector > bdev->bd_part->nr_sects) {
		*nr_zones = 0;
		return 0;
	}

	/*
	 * The zone report has a header. So make room for it in the
	 * payload. Also make sure that the report fits in a single BIO
	 * that will not be split down the stack.
	 */
	rep_bytes = sizeof(struct blk_zone_report_hdr) +
		sizeof(struct blk_zone) * nrz;
	rep_bytes = (rep_bytes + PAGE_SIZE - 1) & PAGE_MASK;
	if (rep_bytes > (queue_max_sectors(q) << 9))
		rep_bytes = queue_max_sectors(q) << 9;

	nr_pages = min_t(unsigned int, BIO_MAX_PAGES,
			 rep_bytes >> PAGE_SHIFT);
	nr_pages = min_t(unsigned int, nr_pages,
			 queue_max_segments(q));

	bio = bio_alloc(gfp_mask, nr_pages);
	if (!bio)
		return -ENOMEM;

	bio_set_dev(bio, bdev);
	bio->bi_iter.bi_sector = blk_zone_start(q, sector);
	bio_set_op_attrs(bio, REQ_OP_ZONE_REPORT, 0);

	for (i = 0; i < nr_pages; i++) {
		page = alloc_page(gfp_mask);
		if (!page) {
			ret = -ENOMEM;
			goto out;
		}
		if (!bio_add_page(bio, page, PAGE_SIZE, 0)) {
			__free_page(page);
			break;
		}
	}

	if (i == 0)
		ret = -ENOMEM;
	else
		ret = submit_bio_wait(bio);
	if (ret)
		goto out;

	/*
	 * Process the report result: skip the header and go through the
	 * reported zones to fixup and fixup the zone information for
	 * partitions. At the same time, return the zone information into
	 * the zone array.
	 */
	n = 0;
	nz = 0;
	nr_rep = 0;
	bio_for_each_segment_all(bv, bio, i) {

		if (!bv->bv_page)
			break;

		addr = kmap_atomic(bv->bv_page);

		/* Get header in the first page */
		ofst = 0;
		if (!nr_rep) {
			hdr = (struct blk_zone_report_hdr *) addr;
			nr_rep = hdr->nr_zones;
			ofst = sizeof(struct blk_zone_report_hdr);
		}

		/* Fixup and report zones */
		while (ofst < bv->bv_len &&
		       n < nr_rep && nz < nrz) {
			if (blkdev_report_zone(bdev, addr + ofst, &zones[nz]))
				nz++;
			ofst += sizeof(struct blk_zone);
			n++;
		}

		kunmap_atomic(addr);

		if (n >= nr_rep || nz >= nrz)
			break;

	}

	*nr_zones = nz;
out:
	bio_for_each_segment_all(bv, bio, i)
		__free_page(bv->bv_page);
	bio_put(bio);

	return ret;
}
EXPORT_SYMBOL_GPL(blkdev_report_zones);

/**
 * blkdev_reset_zones - Reset zones write pointer
 * @bdev:	Target block device
 * @sector:	Start sector of the first zone to reset
 * @nr_sectors:	Number of sectors, at least the length of one zone
 * @gfp_mask:	Memory allocation flags (for bio_alloc)
 *
 * Description:
 *    Reset the write pointer of the zones contained in the range
 *    @sector..@sector+@nr_sectors. Specifying the entire disk sector range
 *    is valid, but the specified range should not contain conventional zones.
 */
int blkdev_reset_zones(struct block_device *bdev,
		       sector_t sector, sector_t nr_sectors,
		       gfp_t gfp_mask)
{
	struct request_queue *q = bdev_get_queue(bdev);
	sector_t zone_sectors;
	sector_t end_sector = sector + nr_sectors;
	struct bio *bio;
	int ret;

	if (!q)
		return -ENXIO;

	if (!blk_queue_is_zoned(q))
		return -EOPNOTSUPP;

	if (end_sector > bdev->bd_part->nr_sects)
		/* Out of range */
		return -EINVAL;

	/* Check alignment (handle eventual smaller last zone) */
	zone_sectors = blk_queue_zone_sectors(q);
	if (sector & (zone_sectors - 1))
		return -EINVAL;

	if ((nr_sectors & (zone_sectors - 1)) &&
	    end_sector != bdev->bd_part->nr_sects)
		return -EINVAL;

	while (sector < end_sector) {

		bio = bio_alloc(gfp_mask, 0);
		bio->bi_iter.bi_sector = sector;
		bio_set_dev(bio, bdev);
		bio_set_op_attrs(bio, REQ_OP_ZONE_RESET, 0);

		ret = submit_bio_wait(bio);
		bio_put(bio);

		if (ret)
			return ret;

		sector += zone_sectors;

		/* This may take a while, so be nice to others */
		cond_resched();

	}

	return 0;
}
EXPORT_SYMBOL_GPL(blkdev_reset_zones);

/**
 * BLKREPORTZONE ioctl processing.
 * Called from blkdev_ioctl.
 */
int blkdev_report_zones_ioctl(struct block_device *bdev, fmode_t mode,
			      unsigned int cmd, unsigned long arg)
{
	void __user *argp = (void __user *)arg;
	struct request_queue *q;
	struct blk_zone_report rep;
	struct blk_zone *zones;
	int ret;

	if (!argp)
		return -EINVAL;

	q = bdev_get_queue(bdev);
	if (!q)
		return -ENXIO;

	if (!blk_queue_is_zoned(q))
		return -ENOTTY;

	if (!capable(CAP_SYS_ADMIN))
		return -EACCES;

	if (copy_from_user(&rep, argp, sizeof(struct blk_zone_report)))
		return -EFAULT;

	if (!rep.nr_zones)
		return -EINVAL;

	zones = kcalloc(rep.nr_zones, sizeof(struct blk_zone), GFP_KERNEL);
	if (!zones)
		return -ENOMEM;

	ret = blkdev_report_zones(bdev, rep.sector,
				  zones, &rep.nr_zones,
				  GFP_KERNEL);
	if (ret)
		goto out;

	if (copy_to_user(argp, &rep, sizeof(struct blk_zone_report))) {
		ret = -EFAULT;
		goto out;
	}

	if (rep.nr_zones) {
		if (copy_to_user(argp + sizeof(struct blk_zone_report), zones,
				 sizeof(struct blk_zone) * rep.nr_zones))
			ret = -EFAULT;
	}

 out:
	kfree(zones);

	return ret;
}

/**
 * BLKRESETZONE ioctl processing.
 * Called from blkdev_ioctl.
 */
int blkdev_reset_zones_ioctl(struct block_device *bdev, fmode_t mode,
			     unsigned int cmd, unsigned long arg)
{
	void __user *argp = (void __user *)arg;
	struct request_queue *q;
	struct blk_zone_range zrange;

	if (!argp)
		return -EINVAL;

	q = bdev_get_queue(bdev);
	if (!q)
		return -ENXIO;

	if (!blk_queue_is_zoned(q))
		return -ENOTTY;

	if (!capable(CAP_SYS_ADMIN))
		return -EACCES;

	if (!(mode & FMODE_WRITE))
		return -EBADF;

	if (copy_from_user(&zrange, argp, sizeof(struct blk_zone_range)))
		return -EFAULT;

	return blkdev_reset_zones(bdev, zrange.sector, zrange.nr_sectors,
				  GFP_KERNEL);
}