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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * SCSI Zoned Block commands
4 *
5 * Copyright (C) 2014-2015 SUSE Linux GmbH
6 * Written by: Hannes Reinecke <hare@suse.de>
7 * Modified by: Damien Le Moal <damien.lemoal@hgst.com>
8 * Modified by: Shaun Tancheff <shaun.tancheff@seagate.com>
9 */
10
11#include <linux/blkdev.h>
12#include <linux/vmalloc.h>
13#include <linux/sched/mm.h>
14#include <linux/mutex.h>
15
16#include <linux/unaligned.h>
17
18#include <scsi/scsi.h>
19#include <scsi/scsi_cmnd.h>
20
21#include "sd.h"
22
23#define CREATE_TRACE_POINTS
24#include "sd_trace.h"
25
26/* Whether or not a SCSI zone descriptor describes a gap zone. */
27static bool sd_zbc_is_gap_zone(const u8 buf[64])
28{
29 return (buf[0] & 0xf) == ZBC_ZONE_TYPE_GAP;
30}
31
32/**
33 * sd_zbc_parse_report - Parse a SCSI zone descriptor
34 * @sdkp: SCSI disk pointer.
35 * @buf: SCSI zone descriptor.
36 * @idx: Index of the zone relative to the first zone reported by the current
37 * sd_zbc_report_zones() call.
38 * @cb: Callback function pointer.
39 * @data: Second argument passed to @cb.
40 *
41 * Return: Value returned by @cb.
42 *
43 * Convert a SCSI zone descriptor into struct blk_zone format. Additionally,
44 * call @cb(blk_zone, @data).
45 */
46static int sd_zbc_parse_report(struct scsi_disk *sdkp, const u8 buf[64],
47 unsigned int idx, report_zones_cb cb, void *data)
48{
49 struct scsi_device *sdp = sdkp->device;
50 struct blk_zone zone = { 0 };
51 sector_t start_lba, gran;
52 int ret;
53
54 if (WARN_ON_ONCE(sd_zbc_is_gap_zone(buf)))
55 return -EINVAL;
56
57 zone.type = buf[0] & 0x0f;
58 zone.cond = (buf[1] >> 4) & 0xf;
59 if (buf[1] & 0x01)
60 zone.reset = 1;
61 if (buf[1] & 0x02)
62 zone.non_seq = 1;
63
64 start_lba = get_unaligned_be64(&buf[16]);
65 zone.start = logical_to_sectors(sdp, start_lba);
66 zone.capacity = logical_to_sectors(sdp, get_unaligned_be64(&buf[8]));
67 zone.len = zone.capacity;
68 if (sdkp->zone_starting_lba_gran) {
69 gran = logical_to_sectors(sdp, sdkp->zone_starting_lba_gran);
70 if (zone.len > gran) {
71 sd_printk(KERN_ERR, sdkp,
72 "Invalid zone at LBA %llu with capacity %llu and length %llu; granularity = %llu\n",
73 start_lba,
74 sectors_to_logical(sdp, zone.capacity),
75 sectors_to_logical(sdp, zone.len),
76 sectors_to_logical(sdp, gran));
77 return -EINVAL;
78 }
79 /*
80 * Use the starting LBA granularity instead of the zone length
81 * obtained from the REPORT ZONES command.
82 */
83 zone.len = gran;
84 }
85 if (zone.cond == ZBC_ZONE_COND_FULL)
86 zone.wp = zone.start + zone.len;
87 else
88 zone.wp = logical_to_sectors(sdp, get_unaligned_be64(&buf[24]));
89
90 ret = cb(&zone, idx, data);
91 if (ret)
92 return ret;
93
94 return 0;
95}
96
97/**
98 * sd_zbc_do_report_zones - Issue a REPORT ZONES scsi command.
99 * @sdkp: The target disk
100 * @buf: vmalloc-ed buffer to use for the reply
101 * @buflen: the buffer size
102 * @lba: Start LBA of the report
103 * @partial: Do partial report
104 *
105 * For internal use during device validation.
106 * Using partial=true can significantly speed up execution of a report zones
107 * command because the disk does not have to count all possible report matching
108 * zones and will only report the count of zones fitting in the command reply
109 * buffer.
110 */
111static int sd_zbc_do_report_zones(struct scsi_disk *sdkp, unsigned char *buf,
112 unsigned int buflen, sector_t lba,
113 bool partial)
114{
115 struct scsi_device *sdp = sdkp->device;
116 const int timeout = sdp->request_queue->rq_timeout;
117 struct scsi_sense_hdr sshdr;
118 const struct scsi_exec_args exec_args = {
119 .sshdr = &sshdr,
120 };
121 unsigned char cmd[16];
122 unsigned int rep_len;
123 int result;
124
125 memset(cmd, 0, 16);
126 cmd[0] = ZBC_IN;
127 cmd[1] = ZI_REPORT_ZONES;
128 put_unaligned_be64(lba, &cmd[2]);
129 put_unaligned_be32(buflen, &cmd[10]);
130 if (partial)
131 cmd[14] = ZBC_REPORT_ZONE_PARTIAL;
132
133 result = scsi_execute_cmd(sdp, cmd, REQ_OP_DRV_IN, buf, buflen,
134 timeout, SD_MAX_RETRIES, &exec_args);
135 if (result) {
136 sd_printk(KERN_ERR, sdkp,
137 "REPORT ZONES start lba %llu failed\n", lba);
138 sd_print_result(sdkp, "REPORT ZONES", result);
139 if (result > 0 && scsi_sense_valid(&sshdr))
140 sd_print_sense_hdr(sdkp, &sshdr);
141 return -EIO;
142 }
143
144 rep_len = get_unaligned_be32(&buf[0]);
145 if (rep_len < 64) {
146 sd_printk(KERN_ERR, sdkp,
147 "REPORT ZONES report invalid length %u\n",
148 rep_len);
149 return -EIO;
150 }
151
152 return 0;
153}
154
155/**
156 * sd_zbc_alloc_report_buffer() - Allocate a buffer for report zones reply.
157 * @sdkp: The target disk
158 * @nr_zones: Maximum number of zones to report
159 * @buflen: Size of the buffer allocated
160 *
161 * Try to allocate a reply buffer for the number of requested zones.
162 * The size of the buffer allocated may be smaller than requested to
163 * satify the device constraint (max_hw_sectors, max_segments, etc).
164 *
165 * Return the address of the allocated buffer and update @buflen with
166 * the size of the allocated buffer.
167 */
168static void *sd_zbc_alloc_report_buffer(struct scsi_disk *sdkp,
169 unsigned int nr_zones, size_t *buflen)
170{
171 struct request_queue *q = sdkp->disk->queue;
172 size_t bufsize;
173 void *buf;
174
175 /*
176 * Report zone buffer size should be at most 64B times the number of
177 * zones requested plus the 64B reply header, but should be aligned
178 * to SECTOR_SIZE for ATA devices.
179 * Make sure that this size does not exceed the hardware capabilities.
180 * Furthermore, since the report zone command cannot be split, make
181 * sure that the allocated buffer can always be mapped by limiting the
182 * number of pages allocated to the HBA max segments limit.
183 */
184 nr_zones = min(nr_zones, sdkp->zone_info.nr_zones);
185 bufsize = roundup((nr_zones + 1) * 64, SECTOR_SIZE);
186 bufsize = min_t(size_t, bufsize,
187 queue_max_hw_sectors(q) << SECTOR_SHIFT);
188 bufsize = min_t(size_t, bufsize, queue_max_segments(q) << PAGE_SHIFT);
189
190 while (bufsize >= SECTOR_SIZE) {
191 buf = kvzalloc(bufsize, GFP_KERNEL | __GFP_NORETRY);
192 if (buf) {
193 *buflen = bufsize;
194 return buf;
195 }
196 bufsize = rounddown(bufsize >> 1, SECTOR_SIZE);
197 }
198
199 return NULL;
200}
201
202/**
203 * sd_zbc_zone_sectors - Get the device zone size in number of 512B sectors.
204 * @sdkp: The target disk
205 */
206static inline sector_t sd_zbc_zone_sectors(struct scsi_disk *sdkp)
207{
208 return logical_to_sectors(sdkp->device, sdkp->zone_info.zone_blocks);
209}
210
211/**
212 * sd_zbc_report_zones - SCSI .report_zones() callback.
213 * @disk: Disk to report zones for.
214 * @sector: Start sector.
215 * @nr_zones: Maximum number of zones to report.
216 * @cb: Callback function called to report zone information.
217 * @data: Second argument passed to @cb.
218 *
219 * Called by the block layer to iterate over zone information. See also the
220 * disk->fops->report_zones() calls in block/blk-zoned.c.
221 */
222int sd_zbc_report_zones(struct gendisk *disk, sector_t sector,
223 unsigned int nr_zones, report_zones_cb cb, void *data)
224{
225 struct scsi_disk *sdkp = scsi_disk(disk);
226 sector_t lba = sectors_to_logical(sdkp->device, sector);
227 unsigned int nr, i;
228 unsigned char *buf;
229 u64 zone_length, start_lba;
230 size_t offset, buflen = 0;
231 int zone_idx = 0;
232 int ret;
233
234 if (sdkp->device->type != TYPE_ZBC)
235 /* Not a zoned device */
236 return -EOPNOTSUPP;
237
238 if (!sdkp->capacity)
239 /* Device gone or invalid */
240 return -ENODEV;
241
242 buf = sd_zbc_alloc_report_buffer(sdkp, nr_zones, &buflen);
243 if (!buf)
244 return -ENOMEM;
245
246 while (zone_idx < nr_zones && lba < sdkp->capacity) {
247 ret = sd_zbc_do_report_zones(sdkp, buf, buflen, lba, true);
248 if (ret)
249 goto out;
250
251 offset = 0;
252 nr = min(nr_zones, get_unaligned_be32(&buf[0]) / 64);
253 if (!nr)
254 break;
255
256 for (i = 0; i < nr && zone_idx < nr_zones; i++) {
257 offset += 64;
258 start_lba = get_unaligned_be64(&buf[offset + 16]);
259 zone_length = get_unaligned_be64(&buf[offset + 8]);
260 if ((zone_idx == 0 &&
261 (lba < start_lba ||
262 lba >= start_lba + zone_length)) ||
263 (zone_idx > 0 && start_lba != lba) ||
264 start_lba + zone_length < start_lba) {
265 sd_printk(KERN_ERR, sdkp,
266 "Zone %d at LBA %llu is invalid: %llu + %llu\n",
267 zone_idx, lba, start_lba, zone_length);
268 ret = -EINVAL;
269 goto out;
270 }
271 lba = start_lba + zone_length;
272 if (sd_zbc_is_gap_zone(&buf[offset])) {
273 if (sdkp->zone_starting_lba_gran)
274 continue;
275 sd_printk(KERN_ERR, sdkp,
276 "Gap zone without constant LBA offsets\n");
277 ret = -EINVAL;
278 goto out;
279 }
280
281 ret = sd_zbc_parse_report(sdkp, buf + offset, zone_idx,
282 cb, data);
283 if (ret)
284 goto out;
285
286 zone_idx++;
287 }
288 }
289
290 ret = zone_idx;
291out:
292 kvfree(buf);
293 return ret;
294}
295
296static blk_status_t sd_zbc_cmnd_checks(struct scsi_cmnd *cmd)
297{
298 struct request *rq = scsi_cmd_to_rq(cmd);
299 struct scsi_disk *sdkp = scsi_disk(rq->q->disk);
300 sector_t sector = blk_rq_pos(rq);
301
302 if (sdkp->device->type != TYPE_ZBC)
303 /* Not a zoned device */
304 return BLK_STS_IOERR;
305
306 if (sdkp->device->changed)
307 return BLK_STS_IOERR;
308
309 if (sector & (sd_zbc_zone_sectors(sdkp) - 1))
310 /* Unaligned request */
311 return BLK_STS_IOERR;
312
313 return BLK_STS_OK;
314}
315
316/**
317 * sd_zbc_setup_zone_mgmt_cmnd - Prepare a zone ZBC_OUT command. The operations
318 * can be RESET WRITE POINTER, OPEN, CLOSE or FINISH.
319 * @cmd: the command to setup
320 * @op: Operation to be performed
321 * @all: All zones control
322 *
323 * Called from sd_init_command() for REQ_OP_ZONE_RESET, REQ_OP_ZONE_RESET_ALL,
324 * REQ_OP_ZONE_OPEN, REQ_OP_ZONE_CLOSE or REQ_OP_ZONE_FINISH requests.
325 */
326blk_status_t sd_zbc_setup_zone_mgmt_cmnd(struct scsi_cmnd *cmd,
327 unsigned char op, bool all)
328{
329 struct request *rq = scsi_cmd_to_rq(cmd);
330 sector_t sector = blk_rq_pos(rq);
331 struct scsi_disk *sdkp = scsi_disk(rq->q->disk);
332 sector_t block = sectors_to_logical(sdkp->device, sector);
333 blk_status_t ret;
334
335 ret = sd_zbc_cmnd_checks(cmd);
336 if (ret != BLK_STS_OK)
337 return ret;
338
339 cmd->cmd_len = 16;
340 memset(cmd->cmnd, 0, cmd->cmd_len);
341 cmd->cmnd[0] = ZBC_OUT;
342 cmd->cmnd[1] = op;
343 if (all)
344 cmd->cmnd[14] = 0x1;
345 else
346 put_unaligned_be64(block, &cmd->cmnd[2]);
347
348 rq->timeout = SD_TIMEOUT;
349 cmd->sc_data_direction = DMA_NONE;
350 cmd->transfersize = 0;
351 cmd->allowed = 0;
352
353 return BLK_STS_OK;
354}
355
356/**
357 * sd_zbc_complete - ZBC command post processing.
358 * @cmd: Completed command
359 * @good_bytes: Command reply bytes
360 * @sshdr: command sense header
361 *
362 * Called from sd_done() to handle zone commands errors and updates to the
363 * device queue zone write pointer offset cahce.
364 */
365unsigned int sd_zbc_complete(struct scsi_cmnd *cmd, unsigned int good_bytes,
366 struct scsi_sense_hdr *sshdr)
367{
368 int result = cmd->result;
369 struct request *rq = scsi_cmd_to_rq(cmd);
370
371 if (op_is_zone_mgmt(req_op(rq)) &&
372 result &&
373 sshdr->sense_key == ILLEGAL_REQUEST &&
374 sshdr->asc == 0x24) {
375 /*
376 * INVALID FIELD IN CDB error: a zone management command was
377 * attempted on a conventional zone. Nothing to worry about,
378 * so be quiet about the error.
379 */
380 rq->rq_flags |= RQF_QUIET;
381 }
382
383 return good_bytes;
384}
385
386/**
387 * sd_zbc_check_zoned_characteristics - Check zoned block device characteristics
388 * @sdkp: Target disk
389 * @buf: Buffer where to store the VPD page data
390 *
391 * Read VPD page B6, get information and check that reads are unconstrained.
392 */
393static int sd_zbc_check_zoned_characteristics(struct scsi_disk *sdkp,
394 unsigned char *buf)
395{
396 u64 zone_starting_lba_gran;
397
398 if (scsi_get_vpd_page(sdkp->device, 0xb6, buf, 64)) {
399 sd_printk(KERN_NOTICE, sdkp,
400 "Read zoned characteristics VPD page failed\n");
401 return -ENODEV;
402 }
403
404 if (sdkp->device->type != TYPE_ZBC) {
405 /* Host-aware */
406 sdkp->urswrz = 1;
407 sdkp->zones_optimal_open = get_unaligned_be32(&buf[8]);
408 sdkp->zones_optimal_nonseq = get_unaligned_be32(&buf[12]);
409 sdkp->zones_max_open = 0;
410 return 0;
411 }
412
413 /* Host-managed */
414 sdkp->urswrz = buf[4] & 1;
415 sdkp->zones_optimal_open = 0;
416 sdkp->zones_optimal_nonseq = 0;
417 sdkp->zones_max_open = get_unaligned_be32(&buf[16]);
418 /* Check zone alignment method */
419 switch (buf[23] & 0xf) {
420 case 0:
421 case ZBC_CONSTANT_ZONE_LENGTH:
422 /* Use zone length */
423 break;
424 case ZBC_CONSTANT_ZONE_START_OFFSET:
425 zone_starting_lba_gran = get_unaligned_be64(&buf[24]);
426 if (zone_starting_lba_gran == 0 ||
427 !is_power_of_2(zone_starting_lba_gran) ||
428 logical_to_sectors(sdkp->device, zone_starting_lba_gran) >
429 UINT_MAX) {
430 sd_printk(KERN_ERR, sdkp,
431 "Invalid zone starting LBA granularity %llu\n",
432 zone_starting_lba_gran);
433 return -ENODEV;
434 }
435 sdkp->zone_starting_lba_gran = zone_starting_lba_gran;
436 break;
437 default:
438 sd_printk(KERN_ERR, sdkp, "Invalid zone alignment method\n");
439 return -ENODEV;
440 }
441
442 /*
443 * Check for unconstrained reads: host-managed devices with
444 * constrained reads (drives failing read after write pointer)
445 * are not supported.
446 */
447 if (!sdkp->urswrz) {
448 if (sdkp->first_scan)
449 sd_printk(KERN_NOTICE, sdkp,
450 "constrained reads devices are not supported\n");
451 return -ENODEV;
452 }
453
454 return 0;
455}
456
457/**
458 * sd_zbc_check_capacity - Check the device capacity
459 * @sdkp: Target disk
460 * @buf: command buffer
461 * @zblocks: zone size in logical blocks
462 *
463 * Get the device zone size and check that the device capacity as reported
464 * by READ CAPACITY matches the max_lba value (plus one) of the report zones
465 * command reply for devices with RC_BASIS == 0.
466 *
467 * Returns 0 upon success or an error code upon failure.
468 */
469static int sd_zbc_check_capacity(struct scsi_disk *sdkp, unsigned char *buf,
470 u32 *zblocks)
471{
472 u64 zone_blocks;
473 sector_t max_lba;
474 unsigned char *rec;
475 int ret;
476
477 /* Do a report zone to get max_lba and the size of the first zone */
478 ret = sd_zbc_do_report_zones(sdkp, buf, SD_BUF_SIZE, 0, false);
479 if (ret)
480 return ret;
481
482 if (sdkp->rc_basis == 0) {
483 /* The max_lba field is the capacity of this device */
484 max_lba = get_unaligned_be64(&buf[8]);
485 if (sdkp->capacity != max_lba + 1) {
486 if (sdkp->first_scan)
487 sd_printk(KERN_WARNING, sdkp,
488 "Changing capacity from %llu to max LBA+1 %llu\n",
489 (unsigned long long)sdkp->capacity,
490 (unsigned long long)max_lba + 1);
491 sdkp->capacity = max_lba + 1;
492 }
493 }
494
495 if (sdkp->zone_starting_lba_gran == 0) {
496 /* Get the size of the first reported zone */
497 rec = buf + 64;
498 zone_blocks = get_unaligned_be64(&rec[8]);
499 if (logical_to_sectors(sdkp->device, zone_blocks) > UINT_MAX) {
500 if (sdkp->first_scan)
501 sd_printk(KERN_NOTICE, sdkp,
502 "Zone size too large\n");
503 return -EFBIG;
504 }
505 } else {
506 zone_blocks = sdkp->zone_starting_lba_gran;
507 }
508
509 if (!is_power_of_2(zone_blocks)) {
510 sd_printk(KERN_ERR, sdkp,
511 "Zone size %llu is not a power of two.\n",
512 zone_blocks);
513 return -EINVAL;
514 }
515
516 *zblocks = zone_blocks;
517
518 return 0;
519}
520
521static void sd_zbc_print_zones(struct scsi_disk *sdkp)
522{
523 if (sdkp->device->type != TYPE_ZBC || !sdkp->capacity)
524 return;
525
526 if (sdkp->capacity & (sdkp->zone_info.zone_blocks - 1))
527 sd_printk(KERN_NOTICE, sdkp,
528 "%u zones of %u logical blocks + 1 runt zone\n",
529 sdkp->zone_info.nr_zones - 1,
530 sdkp->zone_info.zone_blocks);
531 else
532 sd_printk(KERN_NOTICE, sdkp,
533 "%u zones of %u logical blocks\n",
534 sdkp->zone_info.nr_zones,
535 sdkp->zone_info.zone_blocks);
536}
537
538/*
539 * Call blk_revalidate_disk_zones() if any of the zoned disk properties have
540 * changed that make it necessary to call that function. Called by
541 * sd_revalidate_disk() after the gendisk capacity has been set.
542 */
543int sd_zbc_revalidate_zones(struct scsi_disk *sdkp)
544{
545 struct gendisk *disk = sdkp->disk;
546 struct request_queue *q = disk->queue;
547 u32 zone_blocks = sdkp->early_zone_info.zone_blocks;
548 unsigned int nr_zones = sdkp->early_zone_info.nr_zones;
549 unsigned int flags;
550 int ret;
551
552 /*
553 * There is nothing to do for regular disks, including host-aware disks
554 * that have partitions.
555 */
556 if (!blk_queue_is_zoned(q))
557 return 0;
558
559 if (sdkp->zone_info.zone_blocks == zone_blocks &&
560 sdkp->zone_info.nr_zones == nr_zones &&
561 disk->nr_zones == nr_zones)
562 return 0;
563
564 sdkp->zone_info.zone_blocks = zone_blocks;
565 sdkp->zone_info.nr_zones = nr_zones;
566
567 flags = memalloc_noio_save();
568 ret = blk_revalidate_disk_zones(disk);
569 memalloc_noio_restore(flags);
570 if (ret) {
571 sdkp->zone_info = (struct zoned_disk_info){ };
572 sdkp->capacity = 0;
573 return ret;
574 }
575
576 sd_zbc_print_zones(sdkp);
577
578 return 0;
579}
580
581/**
582 * sd_zbc_read_zones - Read zone information and update the request queue
583 * @sdkp: SCSI disk pointer.
584 * @lim: queue limits to read into
585 * @buf: 512 byte buffer used for storing SCSI command output.
586 *
587 * Read zone information and update the request queue zone characteristics and
588 * also the zoned device information in *sdkp. Called by sd_revalidate_disk()
589 * before the gendisk capacity has been set.
590 */
591int sd_zbc_read_zones(struct scsi_disk *sdkp, struct queue_limits *lim,
592 u8 buf[SD_BUF_SIZE])
593{
594 unsigned int nr_zones;
595 u32 zone_blocks = 0;
596 int ret;
597
598 if (sdkp->device->type != TYPE_ZBC)
599 return 0;
600
601 lim->features |= BLK_FEAT_ZONED;
602
603 /*
604 * Per ZBC and ZAC specifications, writes in sequential write required
605 * zones of host-managed devices must be aligned to the device physical
606 * block size.
607 */
608 lim->zone_write_granularity = sdkp->physical_block_size;
609
610 /* READ16/WRITE16/SYNC16 is mandatory for ZBC devices */
611 sdkp->device->use_16_for_rw = 1;
612 sdkp->device->use_10_for_rw = 0;
613 sdkp->device->use_16_for_sync = 1;
614
615 /* Check zoned block device characteristics (unconstrained reads) */
616 ret = sd_zbc_check_zoned_characteristics(sdkp, buf);
617 if (ret)
618 goto err;
619
620 /* Check the device capacity reported by report zones */
621 ret = sd_zbc_check_capacity(sdkp, buf, &zone_blocks);
622 if (ret != 0)
623 goto err;
624
625 nr_zones = round_up(sdkp->capacity, zone_blocks) >> ilog2(zone_blocks);
626 sdkp->early_zone_info.nr_zones = nr_zones;
627 sdkp->early_zone_info.zone_blocks = zone_blocks;
628
629 /* The drive satisfies the kernel restrictions: set it up */
630 if (sdkp->zones_max_open == U32_MAX)
631 lim->max_open_zones = 0;
632 else
633 lim->max_open_zones = sdkp->zones_max_open;
634 lim->max_active_zones = 0;
635 lim->chunk_sectors = logical_to_sectors(sdkp->device, zone_blocks);
636
637 return 0;
638
639err:
640 sdkp->capacity = 0;
641
642 return ret;
643}