1// SPDX-License-Identifier: GPL-2.0-or-later
2/*******************************************************************************
3 * Filename: target_core_pscsi.c
4 *
5 * This file contains the generic target mode <-> Linux SCSI subsystem plugin.
6 *
7 * (c) Copyright 2003-2013 Datera, Inc.
8 *
9 * Nicholas A. Bellinger <nab@kernel.org>
10 *
11 ******************************************************************************/
12
13#include <linux/string.h>
14#include <linux/parser.h>
15#include <linux/timer.h>
16#include <linux/blkdev.h>
17#include <linux/blk_types.h>
18#include <linux/slab.h>
19#include <linux/spinlock.h>
20#include <linux/cdrom.h>
21#include <linux/ratelimit.h>
22#include <linux/module.h>
23#include <asm/unaligned.h>
24
25#include <scsi/scsi_device.h>
26#include <scsi/scsi_host.h>
27#include <scsi/scsi_tcq.h>
28
29#include <target/target_core_base.h>
30#include <target/target_core_backend.h>
31
32#include "target_core_alua.h"
33#include "target_core_internal.h"
34#include "target_core_pscsi.h"
35
36static inline struct pscsi_dev_virt *PSCSI_DEV(struct se_device *dev)
37{
38 return container_of(dev, struct pscsi_dev_virt, dev);
39}
40
41static sense_reason_t pscsi_execute_cmd(struct se_cmd *cmd);
42static enum rq_end_io_ret pscsi_req_done(struct request *, blk_status_t);
43
44/* pscsi_attach_hba():
45 *
46 * pscsi_get_sh() used scsi_host_lookup() to locate struct Scsi_Host.
47 * from the passed SCSI Host ID.
48 */
49static int pscsi_attach_hba(struct se_hba *hba, u32 host_id)
50{
51 struct pscsi_hba_virt *phv;
52
53 phv = kzalloc(size: sizeof(struct pscsi_hba_virt), GFP_KERNEL);
54 if (!phv) {
55 pr_err("Unable to allocate struct pscsi_hba_virt\n");
56 return -ENOMEM;
57 }
58 phv->phv_host_id = host_id;
59 phv->phv_mode = PHV_VIRTUAL_HOST_ID;
60
61 hba->hba_ptr = phv;
62
63 pr_debug("CORE_HBA[%d] - TCM SCSI HBA Driver %s on"
64 " Generic Target Core Stack %s\n", hba->hba_id,
65 PSCSI_VERSION, TARGET_CORE_VERSION);
66 pr_debug("CORE_HBA[%d] - Attached SCSI HBA to Generic\n",
67 hba->hba_id);
68
69 return 0;
70}
71
72static void pscsi_detach_hba(struct se_hba *hba)
73{
74 struct pscsi_hba_virt *phv = hba->hba_ptr;
75 struct Scsi_Host *scsi_host = phv->phv_lld_host;
76
77 if (scsi_host) {
78 scsi_host_put(t: scsi_host);
79
80 pr_debug("CORE_HBA[%d] - Detached SCSI HBA: %s from"
81 " Generic Target Core\n", hba->hba_id,
82 (scsi_host->hostt->name) ? (scsi_host->hostt->name) :
83 "Unknown");
84 } else
85 pr_debug("CORE_HBA[%d] - Detached Virtual SCSI HBA"
86 " from Generic Target Core\n", hba->hba_id);
87
88 kfree(objp: phv);
89 hba->hba_ptr = NULL;
90}
91
92static int pscsi_pmode_enable_hba(struct se_hba *hba, unsigned long mode_flag)
93{
94 struct pscsi_hba_virt *phv = hba->hba_ptr;
95 struct Scsi_Host *sh = phv->phv_lld_host;
96 /*
97 * Release the struct Scsi_Host
98 */
99 if (!mode_flag) {
100 if (!sh)
101 return 0;
102
103 phv->phv_lld_host = NULL;
104 phv->phv_mode = PHV_VIRTUAL_HOST_ID;
105
106 pr_debug("CORE_HBA[%d] - Disabled pSCSI HBA Passthrough"
107 " %s\n", hba->hba_id, (sh->hostt->name) ?
108 (sh->hostt->name) : "Unknown");
109
110 scsi_host_put(t: sh);
111 return 0;
112 }
113 /*
114 * Otherwise, locate struct Scsi_Host from the original passed
115 * pSCSI Host ID and enable for phba mode
116 */
117 sh = scsi_host_lookup(hostnum: phv->phv_host_id);
118 if (!sh) {
119 pr_err("pSCSI: Unable to locate SCSI Host for"
120 " phv_host_id: %d\n", phv->phv_host_id);
121 return -EINVAL;
122 }
123
124 phv->phv_lld_host = sh;
125 phv->phv_mode = PHV_LLD_SCSI_HOST_NO;
126
127 pr_debug("CORE_HBA[%d] - Enabled pSCSI HBA Passthrough %s\n",
128 hba->hba_id, (sh->hostt->name) ? (sh->hostt->name) : "Unknown");
129
130 return 1;
131}
132
133static void pscsi_tape_read_blocksize(struct se_device *dev,
134 struct scsi_device *sdev)
135{
136 unsigned char cdb[MAX_COMMAND_SIZE], *buf;
137 int ret;
138
139 buf = kzalloc(size: 12, GFP_KERNEL);
140 if (!buf)
141 goto out_free;
142
143 memset(cdb, 0, MAX_COMMAND_SIZE);
144 cdb[0] = MODE_SENSE;
145 cdb[4] = 0x0c; /* 12 bytes */
146
147 ret = scsi_execute_cmd(sdev, cmd: cdb, opf: REQ_OP_DRV_IN, buffer: buf, bufflen: 12, HZ, retries: 1, NULL);
148 if (ret)
149 goto out_free;
150
151 /*
152 * If MODE_SENSE still returns zero, set the default value to 1024.
153 */
154 sdev->sector_size = get_unaligned_be24(p: &buf[9]);
155out_free:
156 if (!sdev->sector_size)
157 sdev->sector_size = 1024;
158
159 kfree(objp: buf);
160}
161
162static void
163pscsi_set_inquiry_info(struct scsi_device *sdev, struct t10_wwn *wwn)
164{
165 if (sdev->inquiry_len < INQUIRY_LEN)
166 return;
167 /*
168 * Use sdev->inquiry data from drivers/scsi/scsi_scan.c:scsi_add_lun()
169 */
170 BUILD_BUG_ON(sizeof(wwn->vendor) != INQUIRY_VENDOR_LEN + 1);
171 snprintf(buf: wwn->vendor, size: sizeof(wwn->vendor),
172 fmt: "%." __stringify(INQUIRY_VENDOR_LEN) "s", sdev->vendor);
173 BUILD_BUG_ON(sizeof(wwn->model) != INQUIRY_MODEL_LEN + 1);
174 snprintf(buf: wwn->model, size: sizeof(wwn->model),
175 fmt: "%." __stringify(INQUIRY_MODEL_LEN) "s", sdev->model);
176 BUILD_BUG_ON(sizeof(wwn->revision) != INQUIRY_REVISION_LEN + 1);
177 snprintf(buf: wwn->revision, size: sizeof(wwn->revision),
178 fmt: "%." __stringify(INQUIRY_REVISION_LEN) "s", sdev->rev);
179}
180
181static int
182pscsi_get_inquiry_vpd_serial(struct scsi_device *sdev, struct t10_wwn *wwn)
183{
184 unsigned char cdb[MAX_COMMAND_SIZE], *buf;
185 int ret;
186
187 buf = kzalloc(INQUIRY_VPD_SERIAL_LEN, GFP_KERNEL);
188 if (!buf)
189 return -ENOMEM;
190
191 memset(cdb, 0, MAX_COMMAND_SIZE);
192 cdb[0] = INQUIRY;
193 cdb[1] = 0x01; /* Query VPD */
194 cdb[2] = 0x80; /* Unit Serial Number */
195 put_unaligned_be16(INQUIRY_VPD_SERIAL_LEN, p: &cdb[3]);
196
197 ret = scsi_execute_cmd(sdev, cmd: cdb, opf: REQ_OP_DRV_IN, buffer: buf,
198 INQUIRY_VPD_SERIAL_LEN, HZ, retries: 1, NULL);
199 if (ret)
200 goto out_free;
201
202 snprintf(buf: &wwn->unit_serial[0], INQUIRY_VPD_SERIAL_LEN, fmt: "%s", &buf[4]);
203
204 wwn->t10_dev->dev_flags |= DF_FIRMWARE_VPD_UNIT_SERIAL;
205
206 kfree(objp: buf);
207 return 0;
208
209out_free:
210 kfree(objp: buf);
211 return -EPERM;
212}
213
214static void
215pscsi_get_inquiry_vpd_device_ident(struct scsi_device *sdev,
216 struct t10_wwn *wwn)
217{
218 unsigned char cdb[MAX_COMMAND_SIZE], *buf, *page_83;
219 int ident_len, page_len, off = 4, ret;
220 struct t10_vpd *vpd;
221
222 buf = kzalloc(INQUIRY_VPD_SERIAL_LEN, GFP_KERNEL);
223 if (!buf)
224 return;
225
226 memset(cdb, 0, MAX_COMMAND_SIZE);
227 cdb[0] = INQUIRY;
228 cdb[1] = 0x01; /* Query VPD */
229 cdb[2] = 0x83; /* Device Identifier */
230 put_unaligned_be16(INQUIRY_VPD_DEVICE_IDENTIFIER_LEN, p: &cdb[3]);
231
232 ret = scsi_execute_cmd(sdev, cmd: cdb, opf: REQ_OP_DRV_IN, buffer: buf,
233 INQUIRY_VPD_DEVICE_IDENTIFIER_LEN, HZ, retries: 1, NULL);
234 if (ret)
235 goto out;
236
237 page_len = get_unaligned_be16(p: &buf[2]);
238 while (page_len > 0) {
239 /* Grab a pointer to the Identification descriptor */
240 page_83 = &buf[off];
241 ident_len = page_83[3];
242 if (!ident_len) {
243 pr_err("page_83[3]: identifier"
244 " length zero!\n");
245 break;
246 }
247 pr_debug("T10 VPD Identifier Length: %d\n", ident_len);
248
249 vpd = kzalloc(size: sizeof(struct t10_vpd), GFP_KERNEL);
250 if (!vpd) {
251 pr_err("Unable to allocate memory for"
252 " struct t10_vpd\n");
253 goto out;
254 }
255 INIT_LIST_HEAD(list: &vpd->vpd_list);
256
257 transport_set_vpd_proto_id(vpd, page_83);
258 transport_set_vpd_assoc(vpd, page_83);
259
260 if (transport_set_vpd_ident_type(vpd, page_83) < 0) {
261 off += (ident_len + 4);
262 page_len -= (ident_len + 4);
263 kfree(objp: vpd);
264 continue;
265 }
266 if (transport_set_vpd_ident(vpd, page_83) < 0) {
267 off += (ident_len + 4);
268 page_len -= (ident_len + 4);
269 kfree(objp: vpd);
270 continue;
271 }
272
273 list_add_tail(new: &vpd->vpd_list, head: &wwn->t10_vpd_list);
274 off += (ident_len + 4);
275 page_len -= (ident_len + 4);
276 }
277
278out:
279 kfree(objp: buf);
280}
281
282static int pscsi_add_device_to_list(struct se_device *dev,
283 struct scsi_device *sd)
284{
285 struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
286 struct request_queue *q = sd->request_queue;
287
288 pdv->pdv_sd = sd;
289
290 if (!sd->queue_depth) {
291 sd->queue_depth = PSCSI_DEFAULT_QUEUEDEPTH;
292
293 pr_err("Set broken SCSI Device %d:%d:%llu"
294 " queue_depth to %d\n", sd->channel, sd->id,
295 sd->lun, sd->queue_depth);
296 }
297
298 dev->dev_attrib.hw_block_size =
299 min_not_zero((int)sd->sector_size, 512);
300 dev->dev_attrib.hw_max_sectors =
301 min_not_zero(sd->host->max_sectors, queue_max_hw_sectors(q));
302 dev->dev_attrib.hw_queue_depth = sd->queue_depth;
303
304 /*
305 * Setup our standard INQUIRY info into se_dev->t10_wwn
306 */
307 pscsi_set_inquiry_info(sdev: sd, wwn: &dev->t10_wwn);
308
309 /*
310 * Locate VPD WWN Information used for various purposes within
311 * the Storage Engine.
312 */
313 if (!pscsi_get_inquiry_vpd_serial(sdev: sd, wwn: &dev->t10_wwn)) {
314 /*
315 * If VPD Unit Serial returned GOOD status, try
316 * VPD Device Identification page (0x83).
317 */
318 pscsi_get_inquiry_vpd_device_ident(sdev: sd, wwn: &dev->t10_wwn);
319 }
320
321 /*
322 * For TYPE_TAPE, attempt to determine blocksize with MODE_SENSE.
323 */
324 if (sd->type == TYPE_TAPE) {
325 pscsi_tape_read_blocksize(dev, sdev: sd);
326 dev->dev_attrib.hw_block_size = sd->sector_size;
327 }
328 return 0;
329}
330
331static struct se_device *pscsi_alloc_device(struct se_hba *hba,
332 const char *name)
333{
334 struct pscsi_dev_virt *pdv;
335
336 pdv = kzalloc(size: sizeof(struct pscsi_dev_virt), GFP_KERNEL);
337 if (!pdv) {
338 pr_err("Unable to allocate memory for struct pscsi_dev_virt\n");
339 return NULL;
340 }
341
342 pr_debug("PSCSI: Allocated pdv: %p for %s\n", pdv, name);
343 return &pdv->dev;
344}
345
346/*
347 * Called with struct Scsi_Host->host_lock called.
348 */
349static int pscsi_create_type_disk(struct se_device *dev, struct scsi_device *sd)
350 __releases(sh->host_lock)
351{
352 struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
353 struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
354 struct Scsi_Host *sh = sd->host;
355 struct bdev_handle *bdev_handle;
356 int ret;
357
358 if (scsi_device_get(sd)) {
359 pr_err("scsi_device_get() failed for %d:%d:%d:%llu\n",
360 sh->host_no, sd->channel, sd->id, sd->lun);
361 spin_unlock_irq(lock: sh->host_lock);
362 return -EIO;
363 }
364 spin_unlock_irq(lock: sh->host_lock);
365 /*
366 * Claim exclusive struct block_device access to struct scsi_device
367 * for TYPE_DISK and TYPE_ZBC using supplied udev_path
368 */
369 bdev_handle = bdev_open_by_path(path: dev->udev_path,
370 BLK_OPEN_WRITE | BLK_OPEN_READ, holder: pdv, NULL);
371 if (IS_ERR(ptr: bdev_handle)) {
372 pr_err("pSCSI: bdev_open_by_path() failed\n");
373 scsi_device_put(sd);
374 return PTR_ERR(ptr: bdev_handle);
375 }
376 pdv->pdv_bdev_handle = bdev_handle;
377
378 ret = pscsi_add_device_to_list(dev, sd);
379 if (ret) {
380 bdev_release(handle: bdev_handle);
381 scsi_device_put(sd);
382 return ret;
383 }
384
385 pr_debug("CORE_PSCSI[%d] - Added TYPE_%s for %d:%d:%d:%llu\n",
386 phv->phv_host_id, sd->type == TYPE_DISK ? "DISK" : "ZBC",
387 sh->host_no, sd->channel, sd->id, sd->lun);
388 return 0;
389}
390
391/*
392 * Called with struct Scsi_Host->host_lock called.
393 */
394static int pscsi_create_type_nondisk(struct se_device *dev, struct scsi_device *sd)
395 __releases(sh->host_lock)
396{
397 struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
398 struct Scsi_Host *sh = sd->host;
399 int ret;
400
401 if (scsi_device_get(sd)) {
402 pr_err("scsi_device_get() failed for %d:%d:%d:%llu\n",
403 sh->host_no, sd->channel, sd->id, sd->lun);
404 spin_unlock_irq(lock: sh->host_lock);
405 return -EIO;
406 }
407 spin_unlock_irq(lock: sh->host_lock);
408
409 ret = pscsi_add_device_to_list(dev, sd);
410 if (ret) {
411 scsi_device_put(sd);
412 return ret;
413 }
414 pr_debug("CORE_PSCSI[%d] - Added Type: %s for %d:%d:%d:%llu\n",
415 phv->phv_host_id, scsi_device_type(sd->type), sh->host_no,
416 sd->channel, sd->id, sd->lun);
417
418 return 0;
419}
420
421static int pscsi_configure_device(struct se_device *dev)
422{
423 struct se_hba *hba = dev->se_hba;
424 struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
425 struct scsi_device *sd;
426 struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
427 struct Scsi_Host *sh = phv->phv_lld_host;
428 int legacy_mode_enable = 0;
429 int ret;
430
431 if (!(pdv->pdv_flags & PDF_HAS_CHANNEL_ID) ||
432 !(pdv->pdv_flags & PDF_HAS_TARGET_ID) ||
433 !(pdv->pdv_flags & PDF_HAS_LUN_ID)) {
434 pr_err("Missing scsi_channel_id=, scsi_target_id= and"
435 " scsi_lun_id= parameters\n");
436 return -EINVAL;
437 }
438
439 /*
440 * If not running in PHV_LLD_SCSI_HOST_NO mode, locate the
441 * struct Scsi_Host we will need to bring the TCM/pSCSI object online
442 */
443 if (!sh) {
444 if (phv->phv_mode == PHV_LLD_SCSI_HOST_NO) {
445 pr_err("pSCSI: Unable to locate struct"
446 " Scsi_Host for PHV_LLD_SCSI_HOST_NO\n");
447 return -ENODEV;
448 }
449 /*
450 * For the newer PHV_VIRTUAL_HOST_ID struct scsi_device
451 * reference, we enforce that udev_path has been set
452 */
453 if (!(dev->dev_flags & DF_USING_UDEV_PATH)) {
454 pr_err("pSCSI: udev_path attribute has not"
455 " been set before ENABLE=1\n");
456 return -EINVAL;
457 }
458 /*
459 * If no scsi_host_id= was passed for PHV_VIRTUAL_HOST_ID,
460 * use the original TCM hba ID to reference Linux/SCSI Host No
461 * and enable for PHV_LLD_SCSI_HOST_NO mode.
462 */
463 if (!(pdv->pdv_flags & PDF_HAS_VIRT_HOST_ID)) {
464 if (hba->dev_count) {
465 pr_err("pSCSI: Unable to set hba_mode"
466 " with active devices\n");
467 return -EEXIST;
468 }
469
470 if (pscsi_pmode_enable_hba(hba, mode_flag: 1) != 1)
471 return -ENODEV;
472
473 legacy_mode_enable = 1;
474 hba->hba_flags |= HBA_FLAGS_PSCSI_MODE;
475 sh = phv->phv_lld_host;
476 } else {
477 sh = scsi_host_lookup(hostnum: pdv->pdv_host_id);
478 if (!sh) {
479 pr_err("pSCSI: Unable to locate"
480 " pdv_host_id: %d\n", pdv->pdv_host_id);
481 return -EINVAL;
482 }
483 pdv->pdv_lld_host = sh;
484 }
485 } else {
486 if (phv->phv_mode == PHV_VIRTUAL_HOST_ID) {
487 pr_err("pSCSI: PHV_VIRTUAL_HOST_ID set while"
488 " struct Scsi_Host exists\n");
489 return -EEXIST;
490 }
491 }
492
493 spin_lock_irq(lock: sh->host_lock);
494 list_for_each_entry(sd, &sh->__devices, siblings) {
495 if ((pdv->pdv_channel_id != sd->channel) ||
496 (pdv->pdv_target_id != sd->id) ||
497 (pdv->pdv_lun_id != sd->lun))
498 continue;
499 /*
500 * Functions will release the held struct scsi_host->host_lock
501 * before calling pscsi_add_device_to_list() to register
502 * struct scsi_device with target_core_mod.
503 */
504 switch (sd->type) {
505 case TYPE_DISK:
506 case TYPE_ZBC:
507 ret = pscsi_create_type_disk(dev, sd);
508 break;
509 default:
510 ret = pscsi_create_type_nondisk(dev, sd);
511 break;
512 }
513
514 if (ret) {
515 if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
516 scsi_host_put(t: sh);
517 else if (legacy_mode_enable) {
518 pscsi_pmode_enable_hba(hba, mode_flag: 0);
519 hba->hba_flags &= ~HBA_FLAGS_PSCSI_MODE;
520 }
521 pdv->pdv_sd = NULL;
522 return ret;
523 }
524 return 0;
525 }
526 spin_unlock_irq(lock: sh->host_lock);
527
528 pr_err("pSCSI: Unable to locate %d:%d:%d:%d\n", sh->host_no,
529 pdv->pdv_channel_id, pdv->pdv_target_id, pdv->pdv_lun_id);
530
531 if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
532 scsi_host_put(t: sh);
533 else if (legacy_mode_enable) {
534 pscsi_pmode_enable_hba(hba, mode_flag: 0);
535 hba->hba_flags &= ~HBA_FLAGS_PSCSI_MODE;
536 }
537
538 return -ENODEV;
539}
540
541static void pscsi_dev_call_rcu(struct rcu_head *p)
542{
543 struct se_device *dev = container_of(p, struct se_device, rcu_head);
544 struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
545
546 kfree(objp: pdv);
547}
548
549static void pscsi_free_device(struct se_device *dev)
550{
551 call_rcu(head: &dev->rcu_head, func: pscsi_dev_call_rcu);
552}
553
554static void pscsi_destroy_device(struct se_device *dev)
555{
556 struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
557 struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
558 struct scsi_device *sd = pdv->pdv_sd;
559
560 if (sd) {
561 /*
562 * Release exclusive pSCSI internal struct block_device claim for
563 * struct scsi_device with TYPE_DISK or TYPE_ZBC
564 * from pscsi_create_type_disk()
565 */
566 if ((sd->type == TYPE_DISK || sd->type == TYPE_ZBC) &&
567 pdv->pdv_bdev_handle) {
568 bdev_release(handle: pdv->pdv_bdev_handle);
569 pdv->pdv_bdev_handle = NULL;
570 }
571 /*
572 * For HBA mode PHV_LLD_SCSI_HOST_NO, release the reference
573 * to struct Scsi_Host now.
574 */
575 if ((phv->phv_mode == PHV_LLD_SCSI_HOST_NO) &&
576 (phv->phv_lld_host != NULL))
577 scsi_host_put(t: phv->phv_lld_host);
578 else if (pdv->pdv_lld_host)
579 scsi_host_put(t: pdv->pdv_lld_host);
580
581 scsi_device_put(sd);
582
583 pdv->pdv_sd = NULL;
584 }
585}
586
587static void pscsi_complete_cmd(struct se_cmd *cmd, u8 scsi_status,
588 unsigned char *req_sense, int valid_data)
589{
590 struct pscsi_dev_virt *pdv = PSCSI_DEV(dev: cmd->se_dev);
591 struct scsi_device *sd = pdv->pdv_sd;
592 unsigned char *cdb = cmd->priv;
593
594 /*
595 * Special case for REPORT_LUNs which is emulated and not passed on.
596 */
597 if (!cdb)
598 return;
599
600 /*
601 * Hack to make sure that Write-Protect modepage is set if R/O mode is
602 * forced.
603 */
604 if (!cmd->data_length)
605 goto after_mode_sense;
606
607 if (((cdb[0] == MODE_SENSE) || (cdb[0] == MODE_SENSE_10)) &&
608 scsi_status == SAM_STAT_GOOD) {
609 bool read_only = target_lun_is_rdonly(cmd);
610
611 if (read_only) {
612 unsigned char *buf;
613
614 buf = transport_kmap_data_sg(cmd);
615 if (!buf) {
616 ; /* XXX: TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE */
617 } else {
618 if (cdb[0] == MODE_SENSE_10) {
619 if (!(buf[3] & 0x80))
620 buf[3] |= 0x80;
621 } else {
622 if (!(buf[2] & 0x80))
623 buf[2] |= 0x80;
624 }
625
626 transport_kunmap_data_sg(cmd);
627 }
628 }
629 }
630after_mode_sense:
631
632 if (sd->type != TYPE_TAPE || !cmd->data_length)
633 goto after_mode_select;
634
635 /*
636 * Hack to correctly obtain the initiator requested blocksize for
637 * TYPE_TAPE. Since this value is dependent upon each tape media,
638 * struct scsi_device->sector_size will not contain the correct value
639 * by default, so we go ahead and set it so
640 * TRANSPORT(dev)->get_blockdev() returns the correct value to the
641 * storage engine.
642 */
643 if (((cdb[0] == MODE_SELECT) || (cdb[0] == MODE_SELECT_10)) &&
644 scsi_status == SAM_STAT_GOOD) {
645 unsigned char *buf;
646 u16 bdl;
647 u32 blocksize;
648
649 buf = sg_virt(sg: &cmd->t_data_sg[0]);
650 if (!buf) {
651 pr_err("Unable to get buf for scatterlist\n");
652 goto after_mode_select;
653 }
654
655 if (cdb[0] == MODE_SELECT)
656 bdl = buf[3];
657 else
658 bdl = get_unaligned_be16(p: &buf[6]);
659
660 if (!bdl)
661 goto after_mode_select;
662
663 if (cdb[0] == MODE_SELECT)
664 blocksize = get_unaligned_be24(p: &buf[9]);
665 else
666 blocksize = get_unaligned_be24(p: &buf[13]);
667
668 sd->sector_size = blocksize;
669 }
670after_mode_select:
671
672 if (scsi_status == SAM_STAT_CHECK_CONDITION) {
673 transport_copy_sense_to_cmd(cmd, req_sense);
674
675 /*
676 * check for TAPE device reads with
677 * FM/EOM/ILI set, so that we can get data
678 * back despite framework assumption that a
679 * check condition means there is no data
680 */
681 if (sd->type == TYPE_TAPE && valid_data &&
682 cmd->data_direction == DMA_FROM_DEVICE) {
683 /*
684 * is sense data valid, fixed format,
685 * and have FM, EOM, or ILI set?
686 */
687 if (req_sense[0] == 0xf0 && /* valid, fixed format */
688 req_sense[2] & 0xe0 && /* FM, EOM, or ILI */
689 (req_sense[2] & 0xf) == 0) { /* key==NO_SENSE */
690 pr_debug("Tape FM/EOM/ILI status detected. Treat as normal read.\n");
691 cmd->se_cmd_flags |= SCF_TREAT_READ_AS_NORMAL;
692 }
693 }
694 }
695}
696
697enum {
698 Opt_scsi_host_id, Opt_scsi_channel_id, Opt_scsi_target_id,
699 Opt_scsi_lun_id, Opt_err
700};
701
702static match_table_t tokens = {
703 {Opt_scsi_host_id, "scsi_host_id=%d"},
704 {Opt_scsi_channel_id, "scsi_channel_id=%d"},
705 {Opt_scsi_target_id, "scsi_target_id=%d"},
706 {Opt_scsi_lun_id, "scsi_lun_id=%d"},
707 {Opt_err, NULL}
708};
709
710static ssize_t pscsi_set_configfs_dev_params(struct se_device *dev,
711 const char *page, ssize_t count)
712{
713 struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
714 struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
715 char *orig, *ptr, *opts;
716 substring_t args[MAX_OPT_ARGS];
717 int ret = 0, arg, token;
718
719 opts = kstrdup(s: page, GFP_KERNEL);
720 if (!opts)
721 return -ENOMEM;
722
723 orig = opts;
724
725 while ((ptr = strsep(&opts, ",\n")) != NULL) {
726 if (!*ptr)
727 continue;
728
729 token = match_token(ptr, table: tokens, args);
730 switch (token) {
731 case Opt_scsi_host_id:
732 if (phv->phv_mode == PHV_LLD_SCSI_HOST_NO) {
733 pr_err("PSCSI[%d]: Unable to accept"
734 " scsi_host_id while phv_mode =="
735 " PHV_LLD_SCSI_HOST_NO\n",
736 phv->phv_host_id);
737 ret = -EINVAL;
738 goto out;
739 }
740 ret = match_int(args, result: &arg);
741 if (ret)
742 goto out;
743 pdv->pdv_host_id = arg;
744 pr_debug("PSCSI[%d]: Referencing SCSI Host ID:"
745 " %d\n", phv->phv_host_id, pdv->pdv_host_id);
746 pdv->pdv_flags |= PDF_HAS_VIRT_HOST_ID;
747 break;
748 case Opt_scsi_channel_id:
749 ret = match_int(args, result: &arg);
750 if (ret)
751 goto out;
752 pdv->pdv_channel_id = arg;
753 pr_debug("PSCSI[%d]: Referencing SCSI Channel"
754 " ID: %d\n", phv->phv_host_id,
755 pdv->pdv_channel_id);
756 pdv->pdv_flags |= PDF_HAS_CHANNEL_ID;
757 break;
758 case Opt_scsi_target_id:
759 ret = match_int(args, result: &arg);
760 if (ret)
761 goto out;
762 pdv->pdv_target_id = arg;
763 pr_debug("PSCSI[%d]: Referencing SCSI Target"
764 " ID: %d\n", phv->phv_host_id,
765 pdv->pdv_target_id);
766 pdv->pdv_flags |= PDF_HAS_TARGET_ID;
767 break;
768 case Opt_scsi_lun_id:
769 ret = match_int(args, result: &arg);
770 if (ret)
771 goto out;
772 pdv->pdv_lun_id = arg;
773 pr_debug("PSCSI[%d]: Referencing SCSI LUN ID:"
774 " %d\n", phv->phv_host_id, pdv->pdv_lun_id);
775 pdv->pdv_flags |= PDF_HAS_LUN_ID;
776 break;
777 default:
778 break;
779 }
780 }
781
782out:
783 kfree(objp: orig);
784 return (!ret) ? count : ret;
785}
786
787static ssize_t pscsi_show_configfs_dev_params(struct se_device *dev, char *b)
788{
789 struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
790 struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
791 struct scsi_device *sd = pdv->pdv_sd;
792 unsigned char host_id[16];
793 ssize_t bl;
794
795 if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
796 snprintf(buf: host_id, size: 16, fmt: "%d", pdv->pdv_host_id);
797 else
798 snprintf(buf: host_id, size: 16, fmt: "PHBA Mode");
799
800 bl = sprintf(buf: b, fmt: "SCSI Device Bus Location:"
801 " Channel ID: %d Target ID: %d LUN: %d Host ID: %s\n",
802 pdv->pdv_channel_id, pdv->pdv_target_id, pdv->pdv_lun_id,
803 host_id);
804
805 if (sd) {
806 bl += sprintf(buf: b + bl, fmt: " Vendor: %."
807 __stringify(INQUIRY_VENDOR_LEN) "s", sd->vendor);
808 bl += sprintf(buf: b + bl, fmt: " Model: %."
809 __stringify(INQUIRY_MODEL_LEN) "s", sd->model);
810 bl += sprintf(buf: b + bl, fmt: " Rev: %."
811 __stringify(INQUIRY_REVISION_LEN) "s\n", sd->rev);
812 }
813 return bl;
814}
815
816static void pscsi_bi_endio(struct bio *bio)
817{
818 bio_uninit(bio);
819 kfree(objp: bio);
820}
821
822static sense_reason_t
823pscsi_map_sg(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
824 struct request *req)
825{
826 struct pscsi_dev_virt *pdv = PSCSI_DEV(dev: cmd->se_dev);
827 struct bio *bio = NULL;
828 struct page *page;
829 struct scatterlist *sg;
830 u32 data_len = cmd->data_length, i, len, bytes, off;
831 int nr_pages = (cmd->data_length + sgl[0].offset +
832 PAGE_SIZE - 1) >> PAGE_SHIFT;
833 int nr_vecs = 0, rc;
834 int rw = (cmd->data_direction == DMA_TO_DEVICE);
835
836 BUG_ON(!cmd->data_length);
837
838 pr_debug("PSCSI: nr_pages: %d\n", nr_pages);
839
840 for_each_sg(sgl, sg, sgl_nents, i) {
841 page = sg_page(sg);
842 off = sg->offset;
843 len = sg->length;
844
845 pr_debug("PSCSI: i: %d page: %p len: %d off: %d\n", i,
846 page, len, off);
847
848 /*
849 * We only have one page of data in each sg element,
850 * we can not cross a page boundary.
851 */
852 if (off + len > PAGE_SIZE)
853 goto fail;
854
855 if (len > 0 && data_len > 0) {
856 bytes = min_t(unsigned int, len, PAGE_SIZE - off);
857 bytes = min(bytes, data_len);
858
859 if (!bio) {
860new_bio:
861 nr_vecs = bio_max_segs(nr_segs: nr_pages);
862 bio = bio_kmalloc(nr_vecs, GFP_KERNEL);
863 if (!bio)
864 goto fail;
865 bio_init(bio, NULL, table: bio->bi_inline_vecs, max_vecs: nr_vecs,
866 opf: rw ? REQ_OP_WRITE : REQ_OP_READ);
867 bio->bi_end_io = pscsi_bi_endio;
868
869 pr_debug("PSCSI: Allocated bio: %p,"
870 " dir: %s nr_vecs: %d\n", bio,
871 (rw) ? "rw" : "r", nr_vecs);
872 }
873
874 pr_debug("PSCSI: Calling bio_add_pc_page() i: %d"
875 " bio: %p page: %p len: %d off: %d\n", i, bio,
876 page, len, off);
877
878 rc = bio_add_pc_page(pdv->pdv_sd->request_queue,
879 bio, page, bytes, off);
880 pr_debug("PSCSI: bio->bi_vcnt: %d nr_vecs: %d\n",
881 bio_segments(bio), nr_vecs);
882 if (rc != bytes) {
883 pr_debug("PSCSI: Reached bio->bi_vcnt max:"
884 " %d i: %d bio: %p, allocating another"
885 " bio\n", bio->bi_vcnt, i, bio);
886
887 rc = blk_rq_append_bio(rq: req, bio);
888 if (rc) {
889 pr_err("pSCSI: failed to append bio\n");
890 goto fail;
891 }
892
893 goto new_bio;
894 }
895
896 data_len -= bytes;
897 }
898 }
899
900 if (bio) {
901 rc = blk_rq_append_bio(rq: req, bio);
902 if (rc) {
903 pr_err("pSCSI: failed to append bio\n");
904 goto fail;
905 }
906 }
907
908 return 0;
909fail:
910 if (bio)
911 bio_put(bio);
912 while (req->bio) {
913 bio = req->bio;
914 req->bio = bio->bi_next;
915 bio_put(bio);
916 }
917 req->biotail = NULL;
918 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
919}
920
921static sense_reason_t
922pscsi_parse_cdb(struct se_cmd *cmd)
923{
924 if (cmd->se_cmd_flags & SCF_BIDI)
925 return TCM_UNSUPPORTED_SCSI_OPCODE;
926
927 return passthrough_parse_cdb(cmd, exec_cmd: pscsi_execute_cmd);
928}
929
930static sense_reason_t
931pscsi_execute_cmd(struct se_cmd *cmd)
932{
933 struct scatterlist *sgl = cmd->t_data_sg;
934 u32 sgl_nents = cmd->t_data_nents;
935 struct pscsi_dev_virt *pdv = PSCSI_DEV(dev: cmd->se_dev);
936 struct scsi_cmnd *scmd;
937 struct request *req;
938 sense_reason_t ret;
939
940 req = scsi_alloc_request(q: pdv->pdv_sd->request_queue,
941 opf: cmd->data_direction == DMA_TO_DEVICE ?
942 REQ_OP_DRV_OUT : REQ_OP_DRV_IN, flags: 0);
943 if (IS_ERR(ptr: req))
944 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
945
946 if (sgl) {
947 ret = pscsi_map_sg(cmd, sgl, sgl_nents, req);
948 if (ret)
949 goto fail_put_request;
950 }
951
952 req->end_io = pscsi_req_done;
953 req->end_io_data = cmd;
954
955 scmd = blk_mq_rq_to_pdu(rq: req);
956 scmd->cmd_len = scsi_command_size(cmnd: cmd->t_task_cdb);
957 if (scmd->cmd_len > sizeof(scmd->cmnd)) {
958 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
959 goto fail_put_request;
960 }
961 memcpy(scmd->cmnd, cmd->t_task_cdb, scmd->cmd_len);
962
963 if (pdv->pdv_sd->type == TYPE_DISK ||
964 pdv->pdv_sd->type == TYPE_ZBC)
965 req->timeout = PS_TIMEOUT_DISK;
966 else
967 req->timeout = PS_TIMEOUT_OTHER;
968 scmd->allowed = PS_RETRY;
969
970 cmd->priv = scmd->cmnd;
971
972 blk_execute_rq_nowait(rq: req, at_head: cmd->sam_task_attr == TCM_HEAD_TAG);
973
974 return 0;
975
976fail_put_request:
977 blk_mq_free_request(rq: req);
978 return ret;
979}
980
981/* pscsi_get_device_type():
982 *
983 *
984 */
985static u32 pscsi_get_device_type(struct se_device *dev)
986{
987 struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
988 struct scsi_device *sd = pdv->pdv_sd;
989
990 return (sd) ? sd->type : TYPE_NO_LUN;
991}
992
993static sector_t pscsi_get_blocks(struct se_device *dev)
994{
995 struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
996
997 if (pdv->pdv_bdev_handle)
998 return bdev_nr_sectors(bdev: pdv->pdv_bdev_handle->bdev);
999 return 0;
1000}
1001
1002static enum rq_end_io_ret pscsi_req_done(struct request *req,
1003 blk_status_t status)
1004{
1005 struct se_cmd *cmd = req->end_io_data;
1006 struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(rq: req);
1007 enum sam_status scsi_status = scmd->result & 0xff;
1008 int valid_data = cmd->data_length - scmd->resid_len;
1009 u8 *cdb = cmd->priv;
1010
1011 if (scsi_status != SAM_STAT_GOOD) {
1012 pr_debug("PSCSI Status Byte exception at cmd: %p CDB:"
1013 " 0x%02x Result: 0x%08x\n", cmd, cdb[0], scmd->result);
1014 }
1015
1016 pscsi_complete_cmd(cmd, scsi_status, req_sense: scmd->sense_buffer, valid_data);
1017
1018 switch (host_byte(scmd->result)) {
1019 case DID_OK:
1020 target_complete_cmd_with_length(cmd, scsi_status, valid_data);
1021 break;
1022 default:
1023 pr_debug("PSCSI Host Byte exception at cmd: %p CDB:"
1024 " 0x%02x Result: 0x%08x\n", cmd, cdb[0], scmd->result);
1025 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
1026 break;
1027 }
1028
1029 blk_mq_free_request(rq: req);
1030 return RQ_END_IO_NONE;
1031}
1032
1033static const struct target_backend_ops pscsi_ops = {
1034 .name = "pscsi",
1035 .owner = THIS_MODULE,
1036 .transport_flags_default = TRANSPORT_FLAG_PASSTHROUGH |
1037 TRANSPORT_FLAG_PASSTHROUGH_ALUA |
1038 TRANSPORT_FLAG_PASSTHROUGH_PGR,
1039 .attach_hba = pscsi_attach_hba,
1040 .detach_hba = pscsi_detach_hba,
1041 .pmode_enable_hba = pscsi_pmode_enable_hba,
1042 .alloc_device = pscsi_alloc_device,
1043 .configure_device = pscsi_configure_device,
1044 .destroy_device = pscsi_destroy_device,
1045 .free_device = pscsi_free_device,
1046 .parse_cdb = pscsi_parse_cdb,
1047 .set_configfs_dev_params = pscsi_set_configfs_dev_params,
1048 .show_configfs_dev_params = pscsi_show_configfs_dev_params,
1049 .get_device_type = pscsi_get_device_type,
1050 .get_blocks = pscsi_get_blocks,
1051 .tb_dev_attrib_attrs = passthrough_attrib_attrs,
1052};
1053
1054static int __init pscsi_module_init(void)
1055{
1056 return transport_backend_register(&pscsi_ops);
1057}
1058
1059static void __exit pscsi_module_exit(void)
1060{
1061 target_backend_unregister(&pscsi_ops);
1062}
1063
1064MODULE_DESCRIPTION("TCM PSCSI subsystem plugin");
1065MODULE_AUTHOR("nab@Linux-iSCSI.org");
1066MODULE_LICENSE("GPL");
1067
1068module_init(pscsi_module_init);
1069module_exit(pscsi_module_exit);
1070

source code of linux/drivers/target/target_core_pscsi.c