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 <asm/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/**
27 * sd_zbc_get_zone_wp_offset - Get zone write pointer offset.
28 * @zone: Zone for which to return the write pointer offset.
29 *
30 * Return: offset of the write pointer from the start of the zone.
31 */
32static unsigned int sd_zbc_get_zone_wp_offset(struct blk_zone *zone)
33{
34 if (zone->type == ZBC_ZONE_TYPE_CONV)
35 return 0;
36
37 switch (zone->cond) {
38 case BLK_ZONE_COND_IMP_OPEN:
39 case BLK_ZONE_COND_EXP_OPEN:
40 case BLK_ZONE_COND_CLOSED:
41 return zone->wp - zone->start;
42 case BLK_ZONE_COND_FULL:
43 return zone->len;
44 case BLK_ZONE_COND_EMPTY:
45 case BLK_ZONE_COND_OFFLINE:
46 case BLK_ZONE_COND_READONLY:
47 default:
48 /*
49 * Offline and read-only zones do not have a valid
50 * write pointer. Use 0 as for an empty zone.
51 */
52 return 0;
53 }
54}
55
56/* Whether or not a SCSI zone descriptor describes a gap zone. */
57static bool sd_zbc_is_gap_zone(const u8 buf[64])
58{
59 return (buf[0] & 0xf) == ZBC_ZONE_TYPE_GAP;
60}
61
62/**
63 * sd_zbc_parse_report - Parse a SCSI zone descriptor
64 * @sdkp: SCSI disk pointer.
65 * @buf: SCSI zone descriptor.
66 * @idx: Index of the zone relative to the first zone reported by the current
67 * sd_zbc_report_zones() call.
68 * @cb: Callback function pointer.
69 * @data: Second argument passed to @cb.
70 *
71 * Return: Value returned by @cb.
72 *
73 * Convert a SCSI zone descriptor into struct blk_zone format. Additionally,
74 * call @cb(blk_zone, @data).
75 */
76static int sd_zbc_parse_report(struct scsi_disk *sdkp, const u8 buf[64],
77 unsigned int idx, report_zones_cb cb, void *data)
78{
79 struct scsi_device *sdp = sdkp->device;
80 struct blk_zone zone = { 0 };
81 sector_t start_lba, gran;
82 int ret;
83
84 if (WARN_ON_ONCE(sd_zbc_is_gap_zone(buf)))
85 return -EINVAL;
86
87 zone.type = buf[0] & 0x0f;
88 zone.cond = (buf[1] >> 4) & 0xf;
89 if (buf[1] & 0x01)
90 zone.reset = 1;
91 if (buf[1] & 0x02)
92 zone.non_seq = 1;
93
94 start_lba = get_unaligned_be64(p: &buf[16]);
95 zone.start = logical_to_sectors(sdev: sdp, blocks: start_lba);
96 zone.capacity = logical_to_sectors(sdev: sdp, blocks: get_unaligned_be64(p: &buf[8]));
97 zone.len = zone.capacity;
98 if (sdkp->zone_starting_lba_gran) {
99 gran = logical_to_sectors(sdev: sdp, blocks: sdkp->zone_starting_lba_gran);
100 if (zone.len > gran) {
101 sd_printk(KERN_ERR, sdkp,
102 "Invalid zone at LBA %llu with capacity %llu and length %llu; granularity = %llu\n",
103 start_lba,
104 sectors_to_logical(sdp, zone.capacity),
105 sectors_to_logical(sdp, zone.len),
106 sectors_to_logical(sdp, gran));
107 return -EINVAL;
108 }
109 /*
110 * Use the starting LBA granularity instead of the zone length
111 * obtained from the REPORT ZONES command.
112 */
113 zone.len = gran;
114 }
115 if (zone.cond == ZBC_ZONE_COND_FULL)
116 zone.wp = zone.start + zone.len;
117 else
118 zone.wp = logical_to_sectors(sdev: sdp, blocks: get_unaligned_be64(p: &buf[24]));
119
120 ret = cb(&zone, idx, data);
121 if (ret)
122 return ret;
123
124 if (sdkp->rev_wp_offset)
125 sdkp->rev_wp_offset[idx] = sd_zbc_get_zone_wp_offset(zone: &zone);
126
127 return 0;
128}
129
130/**
131 * sd_zbc_do_report_zones - Issue a REPORT ZONES scsi command.
132 * @sdkp: The target disk
133 * @buf: vmalloc-ed buffer to use for the reply
134 * @buflen: the buffer size
135 * @lba: Start LBA of the report
136 * @partial: Do partial report
137 *
138 * For internal use during device validation.
139 * Using partial=true can significantly speed up execution of a report zones
140 * command because the disk does not have to count all possible report matching
141 * zones and will only report the count of zones fitting in the command reply
142 * buffer.
143 */
144static int sd_zbc_do_report_zones(struct scsi_disk *sdkp, unsigned char *buf,
145 unsigned int buflen, sector_t lba,
146 bool partial)
147{
148 struct scsi_device *sdp = sdkp->device;
149 const int timeout = sdp->request_queue->rq_timeout;
150 struct scsi_sense_hdr sshdr;
151 const struct scsi_exec_args exec_args = {
152 .sshdr = &sshdr,
153 };
154 unsigned char cmd[16];
155 unsigned int rep_len;
156 int result;
157
158 memset(cmd, 0, 16);
159 cmd[0] = ZBC_IN;
160 cmd[1] = ZI_REPORT_ZONES;
161 put_unaligned_be64(val: lba, p: &cmd[2]);
162 put_unaligned_be32(val: buflen, p: &cmd[10]);
163 if (partial)
164 cmd[14] = ZBC_REPORT_ZONE_PARTIAL;
165
166 result = scsi_execute_cmd(sdev: sdp, cmd, opf: REQ_OP_DRV_IN, buffer: buf, bufflen: buflen,
167 timeout, SD_MAX_RETRIES, args: &exec_args);
168 if (result) {
169 sd_printk(KERN_ERR, sdkp,
170 "REPORT ZONES start lba %llu failed\n", lba);
171 sd_print_result(sdkp, msg: "REPORT ZONES", result);
172 if (result > 0 && scsi_sense_valid(sshdr: &sshdr))
173 sd_print_sense_hdr(sdkp, sshdr: &sshdr);
174 return -EIO;
175 }
176
177 rep_len = get_unaligned_be32(p: &buf[0]);
178 if (rep_len < 64) {
179 sd_printk(KERN_ERR, sdkp,
180 "REPORT ZONES report invalid length %u\n",
181 rep_len);
182 return -EIO;
183 }
184
185 return 0;
186}
187
188/**
189 * sd_zbc_alloc_report_buffer() - Allocate a buffer for report zones reply.
190 * @sdkp: The target disk
191 * @nr_zones: Maximum number of zones to report
192 * @buflen: Size of the buffer allocated
193 *
194 * Try to allocate a reply buffer for the number of requested zones.
195 * The size of the buffer allocated may be smaller than requested to
196 * satify the device constraint (max_hw_sectors, max_segments, etc).
197 *
198 * Return the address of the allocated buffer and update @buflen with
199 * the size of the allocated buffer.
200 */
201static void *sd_zbc_alloc_report_buffer(struct scsi_disk *sdkp,
202 unsigned int nr_zones, size_t *buflen)
203{
204 struct request_queue *q = sdkp->disk->queue;
205 size_t bufsize;
206 void *buf;
207
208 /*
209 * Report zone buffer size should be at most 64B times the number of
210 * zones requested plus the 64B reply header, but should be aligned
211 * to SECTOR_SIZE for ATA devices.
212 * Make sure that this size does not exceed the hardware capabilities.
213 * Furthermore, since the report zone command cannot be split, make
214 * sure that the allocated buffer can always be mapped by limiting the
215 * number of pages allocated to the HBA max segments limit.
216 */
217 nr_zones = min(nr_zones, sdkp->zone_info.nr_zones);
218 bufsize = roundup((nr_zones + 1) * 64, SECTOR_SIZE);
219 bufsize = min_t(size_t, bufsize,
220 queue_max_hw_sectors(q) << SECTOR_SHIFT);
221 bufsize = min_t(size_t, bufsize, queue_max_segments(q) << PAGE_SHIFT);
222
223 while (bufsize >= SECTOR_SIZE) {
224 buf = __vmalloc(size: bufsize,
225 GFP_KERNEL | __GFP_ZERO | __GFP_NORETRY);
226 if (buf) {
227 *buflen = bufsize;
228 return buf;
229 }
230 bufsize = rounddown(bufsize >> 1, SECTOR_SIZE);
231 }
232
233 return NULL;
234}
235
236/**
237 * sd_zbc_zone_sectors - Get the device zone size in number of 512B sectors.
238 * @sdkp: The target disk
239 */
240static inline sector_t sd_zbc_zone_sectors(struct scsi_disk *sdkp)
241{
242 return logical_to_sectors(sdev: sdkp->device, blocks: sdkp->zone_info.zone_blocks);
243}
244
245/**
246 * sd_zbc_report_zones - SCSI .report_zones() callback.
247 * @disk: Disk to report zones for.
248 * @sector: Start sector.
249 * @nr_zones: Maximum number of zones to report.
250 * @cb: Callback function called to report zone information.
251 * @data: Second argument passed to @cb.
252 *
253 * Called by the block layer to iterate over zone information. See also the
254 * disk->fops->report_zones() calls in block/blk-zoned.c.
255 */
256int sd_zbc_report_zones(struct gendisk *disk, sector_t sector,
257 unsigned int nr_zones, report_zones_cb cb, void *data)
258{
259 struct scsi_disk *sdkp = scsi_disk(disk);
260 sector_t lba = sectors_to_logical(sdev: sdkp->device, sector);
261 unsigned int nr, i;
262 unsigned char *buf;
263 u64 zone_length, start_lba;
264 size_t offset, buflen = 0;
265 int zone_idx = 0;
266 int ret;
267
268 if (!sd_is_zoned(sdkp))
269 /* Not a zoned device */
270 return -EOPNOTSUPP;
271
272 if (!sdkp->capacity)
273 /* Device gone or invalid */
274 return -ENODEV;
275
276 buf = sd_zbc_alloc_report_buffer(sdkp, nr_zones, buflen: &buflen);
277 if (!buf)
278 return -ENOMEM;
279
280 while (zone_idx < nr_zones && lba < sdkp->capacity) {
281 ret = sd_zbc_do_report_zones(sdkp, buf, buflen, lba, partial: true);
282 if (ret)
283 goto out;
284
285 offset = 0;
286 nr = min(nr_zones, get_unaligned_be32(&buf[0]) / 64);
287 if (!nr)
288 break;
289
290 for (i = 0; i < nr && zone_idx < nr_zones; i++) {
291 offset += 64;
292 start_lba = get_unaligned_be64(p: &buf[offset + 16]);
293 zone_length = get_unaligned_be64(p: &buf[offset + 8]);
294 if ((zone_idx == 0 &&
295 (lba < start_lba ||
296 lba >= start_lba + zone_length)) ||
297 (zone_idx > 0 && start_lba != lba) ||
298 start_lba + zone_length < start_lba) {
299 sd_printk(KERN_ERR, sdkp,
300 "Zone %d at LBA %llu is invalid: %llu + %llu\n",
301 zone_idx, lba, start_lba, zone_length);
302 ret = -EINVAL;
303 goto out;
304 }
305 lba = start_lba + zone_length;
306 if (sd_zbc_is_gap_zone(buf: &buf[offset])) {
307 if (sdkp->zone_starting_lba_gran)
308 continue;
309 sd_printk(KERN_ERR, sdkp,
310 "Gap zone without constant LBA offsets\n");
311 ret = -EINVAL;
312 goto out;
313 }
314
315 ret = sd_zbc_parse_report(sdkp, buf: buf + offset, idx: zone_idx,
316 cb, data);
317 if (ret)
318 goto out;
319
320 zone_idx++;
321 }
322 }
323
324 ret = zone_idx;
325out:
326 kvfree(addr: buf);
327 return ret;
328}
329
330static blk_status_t sd_zbc_cmnd_checks(struct scsi_cmnd *cmd)
331{
332 struct request *rq = scsi_cmd_to_rq(scmd: cmd);
333 struct scsi_disk *sdkp = scsi_disk(disk: rq->q->disk);
334 sector_t sector = blk_rq_pos(rq);
335
336 if (!sd_is_zoned(sdkp))
337 /* Not a zoned device */
338 return BLK_STS_IOERR;
339
340 if (sdkp->device->changed)
341 return BLK_STS_IOERR;
342
343 if (sector & (sd_zbc_zone_sectors(sdkp) - 1))
344 /* Unaligned request */
345 return BLK_STS_IOERR;
346
347 return BLK_STS_OK;
348}
349
350#define SD_ZBC_INVALID_WP_OFST (~0u)
351#define SD_ZBC_UPDATING_WP_OFST (SD_ZBC_INVALID_WP_OFST - 1)
352
353static int sd_zbc_update_wp_offset_cb(struct blk_zone *zone, unsigned int idx,
354 void *data)
355{
356 struct scsi_disk *sdkp = data;
357
358 lockdep_assert_held(&sdkp->zones_wp_offset_lock);
359
360 sdkp->zones_wp_offset[idx] = sd_zbc_get_zone_wp_offset(zone);
361
362 return 0;
363}
364
365/*
366 * An attempt to append a zone triggered an invalid write pointer error.
367 * Reread the write pointer of the zone(s) in which the append failed.
368 */
369static void sd_zbc_update_wp_offset_workfn(struct work_struct *work)
370{
371 struct scsi_disk *sdkp;
372 unsigned long flags;
373 sector_t zno;
374 int ret;
375
376 sdkp = container_of(work, struct scsi_disk, zone_wp_offset_work);
377
378 spin_lock_irqsave(&sdkp->zones_wp_offset_lock, flags);
379 for (zno = 0; zno < sdkp->zone_info.nr_zones; zno++) {
380 if (sdkp->zones_wp_offset[zno] != SD_ZBC_UPDATING_WP_OFST)
381 continue;
382
383 spin_unlock_irqrestore(lock: &sdkp->zones_wp_offset_lock, flags);
384 ret = sd_zbc_do_report_zones(sdkp, buf: sdkp->zone_wp_update_buf,
385 SD_BUF_SIZE,
386 lba: zno * sdkp->zone_info.zone_blocks, partial: true);
387 spin_lock_irqsave(&sdkp->zones_wp_offset_lock, flags);
388 if (!ret)
389 sd_zbc_parse_report(sdkp, buf: sdkp->zone_wp_update_buf + 64,
390 idx: zno, cb: sd_zbc_update_wp_offset_cb,
391 data: sdkp);
392 }
393 spin_unlock_irqrestore(lock: &sdkp->zones_wp_offset_lock, flags);
394
395 scsi_device_put(sdkp->device);
396}
397
398/**
399 * sd_zbc_prepare_zone_append() - Prepare an emulated ZONE_APPEND command.
400 * @cmd: the command to setup
401 * @lba: the LBA to patch
402 * @nr_blocks: the number of LBAs to be written
403 *
404 * Called from sd_setup_read_write_cmnd() for REQ_OP_ZONE_APPEND.
405 * @sd_zbc_prepare_zone_append() handles the necessary zone wrote locking and
406 * patching of the lba for an emulated ZONE_APPEND command.
407 *
408 * In case the cached write pointer offset is %SD_ZBC_INVALID_WP_OFST it will
409 * schedule a REPORT ZONES command and return BLK_STS_IOERR.
410 */
411blk_status_t sd_zbc_prepare_zone_append(struct scsi_cmnd *cmd, sector_t *lba,
412 unsigned int nr_blocks)
413{
414 struct request *rq = scsi_cmd_to_rq(scmd: cmd);
415 struct scsi_disk *sdkp = scsi_disk(disk: rq->q->disk);
416 unsigned int wp_offset, zno = blk_rq_zone_no(rq);
417 unsigned long flags;
418 blk_status_t ret;
419
420 ret = sd_zbc_cmnd_checks(cmd);
421 if (ret != BLK_STS_OK)
422 return ret;
423
424 if (!blk_rq_zone_is_seq(rq))
425 return BLK_STS_IOERR;
426
427 /* Unlock of the write lock will happen in sd_zbc_complete() */
428 if (!blk_req_zone_write_trylock(rq))
429 return BLK_STS_ZONE_RESOURCE;
430
431 spin_lock_irqsave(&sdkp->zones_wp_offset_lock, flags);
432 wp_offset = sdkp->zones_wp_offset[zno];
433 switch (wp_offset) {
434 case SD_ZBC_INVALID_WP_OFST:
435 /*
436 * We are about to schedule work to update a zone write pointer
437 * offset, which will cause the zone append command to be
438 * requeued. So make sure that the scsi device does not go away
439 * while the work is being processed.
440 */
441 if (scsi_device_get(sdkp->device)) {
442 ret = BLK_STS_IOERR;
443 break;
444 }
445 sdkp->zones_wp_offset[zno] = SD_ZBC_UPDATING_WP_OFST;
446 schedule_work(work: &sdkp->zone_wp_offset_work);
447 fallthrough;
448 case SD_ZBC_UPDATING_WP_OFST:
449 ret = BLK_STS_DEV_RESOURCE;
450 break;
451 default:
452 wp_offset = sectors_to_logical(sdev: sdkp->device, sector: wp_offset);
453 if (wp_offset + nr_blocks > sdkp->zone_info.zone_blocks) {
454 ret = BLK_STS_IOERR;
455 break;
456 }
457
458 trace_scsi_prepare_zone_append(cmnd: cmd, lba: *lba, wp_offset);
459 *lba += wp_offset;
460 }
461 spin_unlock_irqrestore(lock: &sdkp->zones_wp_offset_lock, flags);
462 if (ret)
463 blk_req_zone_write_unlock(rq);
464 return ret;
465}
466
467/**
468 * sd_zbc_setup_zone_mgmt_cmnd - Prepare a zone ZBC_OUT command. The operations
469 * can be RESET WRITE POINTER, OPEN, CLOSE or FINISH.
470 * @cmd: the command to setup
471 * @op: Operation to be performed
472 * @all: All zones control
473 *
474 * Called from sd_init_command() for REQ_OP_ZONE_RESET, REQ_OP_ZONE_RESET_ALL,
475 * REQ_OP_ZONE_OPEN, REQ_OP_ZONE_CLOSE or REQ_OP_ZONE_FINISH requests.
476 */
477blk_status_t sd_zbc_setup_zone_mgmt_cmnd(struct scsi_cmnd *cmd,
478 unsigned char op, bool all)
479{
480 struct request *rq = scsi_cmd_to_rq(scmd: cmd);
481 sector_t sector = blk_rq_pos(rq);
482 struct scsi_disk *sdkp = scsi_disk(disk: rq->q->disk);
483 sector_t block = sectors_to_logical(sdev: sdkp->device, sector);
484 blk_status_t ret;
485
486 ret = sd_zbc_cmnd_checks(cmd);
487 if (ret != BLK_STS_OK)
488 return ret;
489
490 cmd->cmd_len = 16;
491 memset(cmd->cmnd, 0, cmd->cmd_len);
492 cmd->cmnd[0] = ZBC_OUT;
493 cmd->cmnd[1] = op;
494 if (all)
495 cmd->cmnd[14] = 0x1;
496 else
497 put_unaligned_be64(val: block, p: &cmd->cmnd[2]);
498
499 rq->timeout = SD_TIMEOUT;
500 cmd->sc_data_direction = DMA_NONE;
501 cmd->transfersize = 0;
502 cmd->allowed = 0;
503
504 return BLK_STS_OK;
505}
506
507static bool sd_zbc_need_zone_wp_update(struct request *rq)
508{
509 switch (req_op(req: rq)) {
510 case REQ_OP_ZONE_APPEND:
511 case REQ_OP_ZONE_FINISH:
512 case REQ_OP_ZONE_RESET:
513 case REQ_OP_ZONE_RESET_ALL:
514 return true;
515 case REQ_OP_WRITE:
516 case REQ_OP_WRITE_ZEROES:
517 return blk_rq_zone_is_seq(rq);
518 default:
519 return false;
520 }
521}
522
523/**
524 * sd_zbc_zone_wp_update - Update cached zone write pointer upon cmd completion
525 * @cmd: Completed command
526 * @good_bytes: Command reply bytes
527 *
528 * Called from sd_zbc_complete() to handle the update of the cached zone write
529 * pointer value in case an update is needed.
530 */
531static unsigned int sd_zbc_zone_wp_update(struct scsi_cmnd *cmd,
532 unsigned int good_bytes)
533{
534 int result = cmd->result;
535 struct request *rq = scsi_cmd_to_rq(scmd: cmd);
536 struct scsi_disk *sdkp = scsi_disk(disk: rq->q->disk);
537 unsigned int zno = blk_rq_zone_no(rq);
538 enum req_op op = req_op(req: rq);
539 unsigned long flags;
540
541 /*
542 * If we got an error for a command that needs updating the write
543 * pointer offset cache, we must mark the zone wp offset entry as
544 * invalid to force an update from disk the next time a zone append
545 * command is issued.
546 */
547 spin_lock_irqsave(&sdkp->zones_wp_offset_lock, flags);
548
549 if (result && op != REQ_OP_ZONE_RESET_ALL) {
550 if (op == REQ_OP_ZONE_APPEND) {
551 /* Force complete completion (no retry) */
552 good_bytes = 0;
553 scsi_set_resid(cmd, resid: blk_rq_bytes(rq));
554 }
555
556 /*
557 * Force an update of the zone write pointer offset on
558 * the next zone append access.
559 */
560 if (sdkp->zones_wp_offset[zno] != SD_ZBC_UPDATING_WP_OFST)
561 sdkp->zones_wp_offset[zno] = SD_ZBC_INVALID_WP_OFST;
562 goto unlock_wp_offset;
563 }
564
565 switch (op) {
566 case REQ_OP_ZONE_APPEND:
567 trace_scsi_zone_wp_update(cmnd: cmd, rq_sector: rq->__sector,
568 wp_offset: sdkp->zones_wp_offset[zno], good_bytes);
569 rq->__sector += sdkp->zones_wp_offset[zno];
570 fallthrough;
571 case REQ_OP_WRITE_ZEROES:
572 case REQ_OP_WRITE:
573 if (sdkp->zones_wp_offset[zno] < sd_zbc_zone_sectors(sdkp))
574 sdkp->zones_wp_offset[zno] +=
575 good_bytes >> SECTOR_SHIFT;
576 break;
577 case REQ_OP_ZONE_RESET:
578 sdkp->zones_wp_offset[zno] = 0;
579 break;
580 case REQ_OP_ZONE_FINISH:
581 sdkp->zones_wp_offset[zno] = sd_zbc_zone_sectors(sdkp);
582 break;
583 case REQ_OP_ZONE_RESET_ALL:
584 memset(sdkp->zones_wp_offset, 0,
585 sdkp->zone_info.nr_zones * sizeof(unsigned int));
586 break;
587 default:
588 break;
589 }
590
591unlock_wp_offset:
592 spin_unlock_irqrestore(lock: &sdkp->zones_wp_offset_lock, flags);
593
594 return good_bytes;
595}
596
597/**
598 * sd_zbc_complete - ZBC command post processing.
599 * @cmd: Completed command
600 * @good_bytes: Command reply bytes
601 * @sshdr: command sense header
602 *
603 * Called from sd_done() to handle zone commands errors and updates to the
604 * device queue zone write pointer offset cahce.
605 */
606unsigned int sd_zbc_complete(struct scsi_cmnd *cmd, unsigned int good_bytes,
607 struct scsi_sense_hdr *sshdr)
608{
609 int result = cmd->result;
610 struct request *rq = scsi_cmd_to_rq(scmd: cmd);
611
612 if (op_is_zone_mgmt(op: req_op(req: rq)) &&
613 result &&
614 sshdr->sense_key == ILLEGAL_REQUEST &&
615 sshdr->asc == 0x24) {
616 /*
617 * INVALID FIELD IN CDB error: a zone management command was
618 * attempted on a conventional zone. Nothing to worry about,
619 * so be quiet about the error.
620 */
621 rq->rq_flags |= RQF_QUIET;
622 } else if (sd_zbc_need_zone_wp_update(rq))
623 good_bytes = sd_zbc_zone_wp_update(cmd, good_bytes);
624
625 if (req_op(req: rq) == REQ_OP_ZONE_APPEND)
626 blk_req_zone_write_unlock(rq);
627
628 return good_bytes;
629}
630
631/**
632 * sd_zbc_check_zoned_characteristics - Check zoned block device characteristics
633 * @sdkp: Target disk
634 * @buf: Buffer where to store the VPD page data
635 *
636 * Read VPD page B6, get information and check that reads are unconstrained.
637 */
638static int sd_zbc_check_zoned_characteristics(struct scsi_disk *sdkp,
639 unsigned char *buf)
640{
641 u64 zone_starting_lba_gran;
642
643 if (scsi_get_vpd_page(sdkp->device, page: 0xb6, buf, buf_len: 64)) {
644 sd_printk(KERN_NOTICE, sdkp,
645 "Read zoned characteristics VPD page failed\n");
646 return -ENODEV;
647 }
648
649 if (sdkp->device->type != TYPE_ZBC) {
650 /* Host-aware */
651 sdkp->urswrz = 1;
652 sdkp->zones_optimal_open = get_unaligned_be32(p: &buf[8]);
653 sdkp->zones_optimal_nonseq = get_unaligned_be32(p: &buf[12]);
654 sdkp->zones_max_open = 0;
655 return 0;
656 }
657
658 /* Host-managed */
659 sdkp->urswrz = buf[4] & 1;
660 sdkp->zones_optimal_open = 0;
661 sdkp->zones_optimal_nonseq = 0;
662 sdkp->zones_max_open = get_unaligned_be32(p: &buf[16]);
663 /* Check zone alignment method */
664 switch (buf[23] & 0xf) {
665 case 0:
666 case ZBC_CONSTANT_ZONE_LENGTH:
667 /* Use zone length */
668 break;
669 case ZBC_CONSTANT_ZONE_START_OFFSET:
670 zone_starting_lba_gran = get_unaligned_be64(p: &buf[24]);
671 if (zone_starting_lba_gran == 0 ||
672 !is_power_of_2(n: zone_starting_lba_gran) ||
673 logical_to_sectors(sdev: sdkp->device, blocks: zone_starting_lba_gran) >
674 UINT_MAX) {
675 sd_printk(KERN_ERR, sdkp,
676 "Invalid zone starting LBA granularity %llu\n",
677 zone_starting_lba_gran);
678 return -ENODEV;
679 }
680 sdkp->zone_starting_lba_gran = zone_starting_lba_gran;
681 break;
682 default:
683 sd_printk(KERN_ERR, sdkp, "Invalid zone alignment method\n");
684 return -ENODEV;
685 }
686
687 /*
688 * Check for unconstrained reads: host-managed devices with
689 * constrained reads (drives failing read after write pointer)
690 * are not supported.
691 */
692 if (!sdkp->urswrz) {
693 if (sdkp->first_scan)
694 sd_printk(KERN_NOTICE, sdkp,
695 "constrained reads devices are not supported\n");
696 return -ENODEV;
697 }
698
699 return 0;
700}
701
702/**
703 * sd_zbc_check_capacity - Check the device capacity
704 * @sdkp: Target disk
705 * @buf: command buffer
706 * @zblocks: zone size in logical blocks
707 *
708 * Get the device zone size and check that the device capacity as reported
709 * by READ CAPACITY matches the max_lba value (plus one) of the report zones
710 * command reply for devices with RC_BASIS == 0.
711 *
712 * Returns 0 upon success or an error code upon failure.
713 */
714static int sd_zbc_check_capacity(struct scsi_disk *sdkp, unsigned char *buf,
715 u32 *zblocks)
716{
717 u64 zone_blocks;
718 sector_t max_lba;
719 unsigned char *rec;
720 int ret;
721
722 /* Do a report zone to get max_lba and the size of the first zone */
723 ret = sd_zbc_do_report_zones(sdkp, buf, SD_BUF_SIZE, lba: 0, partial: false);
724 if (ret)
725 return ret;
726
727 if (sdkp->rc_basis == 0) {
728 /* The max_lba field is the capacity of this device */
729 max_lba = get_unaligned_be64(p: &buf[8]);
730 if (sdkp->capacity != max_lba + 1) {
731 if (sdkp->first_scan)
732 sd_printk(KERN_WARNING, sdkp,
733 "Changing capacity from %llu to max LBA+1 %llu\n",
734 (unsigned long long)sdkp->capacity,
735 (unsigned long long)max_lba + 1);
736 sdkp->capacity = max_lba + 1;
737 }
738 }
739
740 if (sdkp->zone_starting_lba_gran == 0) {
741 /* Get the size of the first reported zone */
742 rec = buf + 64;
743 zone_blocks = get_unaligned_be64(p: &rec[8]);
744 if (logical_to_sectors(sdev: sdkp->device, blocks: zone_blocks) > UINT_MAX) {
745 if (sdkp->first_scan)
746 sd_printk(KERN_NOTICE, sdkp,
747 "Zone size too large\n");
748 return -EFBIG;
749 }
750 } else {
751 zone_blocks = sdkp->zone_starting_lba_gran;
752 }
753
754 if (!is_power_of_2(n: zone_blocks)) {
755 sd_printk(KERN_ERR, sdkp,
756 "Zone size %llu is not a power of two.\n",
757 zone_blocks);
758 return -EINVAL;
759 }
760
761 *zblocks = zone_blocks;
762
763 return 0;
764}
765
766static void sd_zbc_print_zones(struct scsi_disk *sdkp)
767{
768 if (!sd_is_zoned(sdkp) || !sdkp->capacity)
769 return;
770
771 if (sdkp->capacity & (sdkp->zone_info.zone_blocks - 1))
772 sd_printk(KERN_NOTICE, sdkp,
773 "%u zones of %u logical blocks + 1 runt zone\n",
774 sdkp->zone_info.nr_zones - 1,
775 sdkp->zone_info.zone_blocks);
776 else
777 sd_printk(KERN_NOTICE, sdkp,
778 "%u zones of %u logical blocks\n",
779 sdkp->zone_info.nr_zones,
780 sdkp->zone_info.zone_blocks);
781}
782
783static int sd_zbc_init_disk(struct scsi_disk *sdkp)
784{
785 sdkp->zones_wp_offset = NULL;
786 spin_lock_init(&sdkp->zones_wp_offset_lock);
787 sdkp->rev_wp_offset = NULL;
788 mutex_init(&sdkp->rev_mutex);
789 INIT_WORK(&sdkp->zone_wp_offset_work, sd_zbc_update_wp_offset_workfn);
790 sdkp->zone_wp_update_buf = kzalloc(SD_BUF_SIZE, GFP_KERNEL);
791 if (!sdkp->zone_wp_update_buf)
792 return -ENOMEM;
793
794 return 0;
795}
796
797void sd_zbc_free_zone_info(struct scsi_disk *sdkp)
798{
799 if (!sdkp->zone_wp_update_buf)
800 return;
801
802 /* Serialize against revalidate zones */
803 mutex_lock(&sdkp->rev_mutex);
804
805 kvfree(addr: sdkp->zones_wp_offset);
806 sdkp->zones_wp_offset = NULL;
807 kfree(objp: sdkp->zone_wp_update_buf);
808 sdkp->zone_wp_update_buf = NULL;
809
810 sdkp->early_zone_info = (struct zoned_disk_info){ };
811 sdkp->zone_info = (struct zoned_disk_info){ };
812
813 mutex_unlock(lock: &sdkp->rev_mutex);
814}
815
816static void sd_zbc_revalidate_zones_cb(struct gendisk *disk)
817{
818 struct scsi_disk *sdkp = scsi_disk(disk);
819
820 swap(sdkp->zones_wp_offset, sdkp->rev_wp_offset);
821}
822
823/*
824 * Call blk_revalidate_disk_zones() if any of the zoned disk properties have
825 * changed that make it necessary to call that function. Called by
826 * sd_revalidate_disk() after the gendisk capacity has been set.
827 */
828int sd_zbc_revalidate_zones(struct scsi_disk *sdkp)
829{
830 struct gendisk *disk = sdkp->disk;
831 struct request_queue *q = disk->queue;
832 u32 zone_blocks = sdkp->early_zone_info.zone_blocks;
833 unsigned int nr_zones = sdkp->early_zone_info.nr_zones;
834 int ret = 0;
835 unsigned int flags;
836
837 /*
838 * For all zoned disks, initialize zone append emulation data if not
839 * already done. This is necessary also for host-aware disks used as
840 * regular disks due to the presence of partitions as these partitions
841 * may be deleted and the disk zoned model changed back from
842 * BLK_ZONED_NONE to BLK_ZONED_HA.
843 */
844 if (sd_is_zoned(sdkp) && !sdkp->zone_wp_update_buf) {
845 ret = sd_zbc_init_disk(sdkp);
846 if (ret)
847 return ret;
848 }
849
850 /*
851 * There is nothing to do for regular disks, including host-aware disks
852 * that have partitions.
853 */
854 if (!blk_queue_is_zoned(q))
855 return 0;
856
857 /*
858 * Make sure revalidate zones are serialized to ensure exclusive
859 * updates of the scsi disk data.
860 */
861 mutex_lock(&sdkp->rev_mutex);
862
863 if (sdkp->zone_info.zone_blocks == zone_blocks &&
864 sdkp->zone_info.nr_zones == nr_zones &&
865 disk->nr_zones == nr_zones)
866 goto unlock;
867
868 flags = memalloc_noio_save();
869 sdkp->zone_info.zone_blocks = zone_blocks;
870 sdkp->zone_info.nr_zones = nr_zones;
871 sdkp->rev_wp_offset = kvcalloc(n: nr_zones, size: sizeof(u32), GFP_KERNEL);
872 if (!sdkp->rev_wp_offset) {
873 ret = -ENOMEM;
874 memalloc_noio_restore(flags);
875 goto unlock;
876 }
877
878 blk_queue_chunk_sectors(q,
879 logical_to_sectors(sdev: sdkp->device, blocks: zone_blocks));
880 blk_queue_max_zone_append_sectors(q,
881 max_zone_append_sectors: q->limits.max_segments << PAGE_SECTORS_SHIFT);
882
883 ret = blk_revalidate_disk_zones(disk, update_driver_data: sd_zbc_revalidate_zones_cb);
884
885 memalloc_noio_restore(flags);
886 kvfree(addr: sdkp->rev_wp_offset);
887 sdkp->rev_wp_offset = NULL;
888
889 if (ret) {
890 sdkp->zone_info = (struct zoned_disk_info){ };
891 sdkp->capacity = 0;
892 goto unlock;
893 }
894
895 sd_zbc_print_zones(sdkp);
896
897unlock:
898 mutex_unlock(lock: &sdkp->rev_mutex);
899
900 return ret;
901}
902
903/**
904 * sd_zbc_read_zones - Read zone information and update the request queue
905 * @sdkp: SCSI disk pointer.
906 * @buf: 512 byte buffer used for storing SCSI command output.
907 *
908 * Read zone information and update the request queue zone characteristics and
909 * also the zoned device information in *sdkp. Called by sd_revalidate_disk()
910 * before the gendisk capacity has been set.
911 */
912int sd_zbc_read_zones(struct scsi_disk *sdkp, u8 buf[SD_BUF_SIZE])
913{
914 struct gendisk *disk = sdkp->disk;
915 struct request_queue *q = disk->queue;
916 unsigned int nr_zones;
917 u32 zone_blocks = 0;
918 int ret;
919
920 if (!sd_is_zoned(sdkp)) {
921 /*
922 * Device managed or normal SCSI disk, no special handling
923 * required. Nevertheless, free the disk zone information in
924 * case the device type changed.
925 */
926 sd_zbc_free_zone_info(sdkp);
927 return 0;
928 }
929
930 /* READ16/WRITE16/SYNC16 is mandatory for ZBC devices */
931 sdkp->device->use_16_for_rw = 1;
932 sdkp->device->use_10_for_rw = 0;
933 sdkp->device->use_16_for_sync = 1;
934
935 if (!blk_queue_is_zoned(q)) {
936 /*
937 * This can happen for a host aware disk with partitions.
938 * The block device zone model was already cleared by
939 * disk_set_zoned(). Only free the scsi disk zone
940 * information and exit early.
941 */
942 sd_zbc_free_zone_info(sdkp);
943 return 0;
944 }
945
946 /* Check zoned block device characteristics (unconstrained reads) */
947 ret = sd_zbc_check_zoned_characteristics(sdkp, buf);
948 if (ret)
949 goto err;
950
951 /* Check the device capacity reported by report zones */
952 ret = sd_zbc_check_capacity(sdkp, buf, zblocks: &zone_blocks);
953 if (ret != 0)
954 goto err;
955
956 /* The drive satisfies the kernel restrictions: set it up */
957 blk_queue_flag_set(QUEUE_FLAG_ZONE_RESETALL, q);
958 blk_queue_required_elevator_features(q, ELEVATOR_F_ZBD_SEQ_WRITE);
959 if (sdkp->zones_max_open == U32_MAX)
960 disk_set_max_open_zones(disk, max_open_zones: 0);
961 else
962 disk_set_max_open_zones(disk, max_open_zones: sdkp->zones_max_open);
963 disk_set_max_active_zones(disk, max_active_zones: 0);
964 nr_zones = round_up(sdkp->capacity, zone_blocks) >> ilog2(zone_blocks);
965
966 sdkp->early_zone_info.nr_zones = nr_zones;
967 sdkp->early_zone_info.zone_blocks = zone_blocks;
968
969 return 0;
970
971err:
972 sdkp->capacity = 0;
973
974 return ret;
975}
976

source code of linux/drivers/scsi/sd_zbc.c