Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / target / target_core_pscsi.c
1 /*******************************************************************************
2  * Filename:  target_core_pscsi.c
3  *
4  * This file contains the generic target mode <-> Linux SCSI subsystem plugin.
5  *
6  * (c) Copyright 2003-2013 Datera, Inc.
7  *
8  * Nicholas A. Bellinger <nab@kernel.org>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or
13  * (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software
22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
23  *
24  ******************************************************************************/
25
26 #include <linux/string.h>
27 #include <linux/parser.h>
28 #include <linux/timer.h>
29 #include <linux/blkdev.h>
30 #include <linux/blk_types.h>
31 #include <linux/slab.h>
32 #include <linux/spinlock.h>
33 #include <linux/genhd.h>
34 #include <linux/cdrom.h>
35 #include <linux/ratelimit.h>
36 #include <linux/module.h>
37 #include <asm/unaligned.h>
38
39 #include <scsi/scsi.h>
40 #include <scsi/scsi_device.h>
41 #include <scsi/scsi_cmnd.h>
42 #include <scsi/scsi_host.h>
43 #include <scsi/scsi_tcq.h>
44
45 #include <target/target_core_base.h>
46 #include <target/target_core_backend.h>
47 #include <target/target_core_backend_configfs.h>
48
49 #include "target_core_alua.h"
50 #include "target_core_pscsi.h"
51
52 #define ISPRINT(a)  ((a >= ' ') && (a <= '~'))
53
54 static inline struct pscsi_dev_virt *PSCSI_DEV(struct se_device *dev)
55 {
56         return container_of(dev, struct pscsi_dev_virt, dev);
57 }
58
59 static struct se_subsystem_api pscsi_template;
60
61 static sense_reason_t pscsi_execute_cmd(struct se_cmd *cmd);
62 static void pscsi_req_done(struct request *, int);
63
64 /*      pscsi_attach_hba():
65  *
66  *      pscsi_get_sh() used scsi_host_lookup() to locate struct Scsi_Host.
67  *      from the passed SCSI Host ID.
68  */
69 static int pscsi_attach_hba(struct se_hba *hba, u32 host_id)
70 {
71         struct pscsi_hba_virt *phv;
72
73         phv = kzalloc(sizeof(struct pscsi_hba_virt), GFP_KERNEL);
74         if (!phv) {
75                 pr_err("Unable to allocate struct pscsi_hba_virt\n");
76                 return -ENOMEM;
77         }
78         phv->phv_host_id = host_id;
79         phv->phv_mode = PHV_VIRTUAL_HOST_ID;
80
81         hba->hba_ptr = phv;
82
83         pr_debug("CORE_HBA[%d] - TCM SCSI HBA Driver %s on"
84                 " Generic Target Core Stack %s\n", hba->hba_id,
85                 PSCSI_VERSION, TARGET_CORE_MOD_VERSION);
86         pr_debug("CORE_HBA[%d] - Attached SCSI HBA to Generic\n",
87                hba->hba_id);
88
89         return 0;
90 }
91
92 static void pscsi_detach_hba(struct se_hba *hba)
93 {
94         struct pscsi_hba_virt *phv = hba->hba_ptr;
95         struct Scsi_Host *scsi_host = phv->phv_lld_host;
96
97         if (scsi_host) {
98                 scsi_host_put(scsi_host);
99
100                 pr_debug("CORE_HBA[%d] - Detached SCSI HBA: %s from"
101                         " Generic Target Core\n", hba->hba_id,
102                         (scsi_host->hostt->name) ? (scsi_host->hostt->name) :
103                         "Unknown");
104         } else
105                 pr_debug("CORE_HBA[%d] - Detached Virtual SCSI HBA"
106                         " from Generic Target Core\n", hba->hba_id);
107
108         kfree(phv);
109         hba->hba_ptr = NULL;
110 }
111
112 static int pscsi_pmode_enable_hba(struct se_hba *hba, unsigned long mode_flag)
113 {
114         struct pscsi_hba_virt *phv = hba->hba_ptr;
115         struct Scsi_Host *sh = phv->phv_lld_host;
116         /*
117          * Release the struct Scsi_Host
118          */
119         if (!mode_flag) {
120                 if (!sh)
121                         return 0;
122
123                 phv->phv_lld_host = NULL;
124                 phv->phv_mode = PHV_VIRTUAL_HOST_ID;
125
126                 pr_debug("CORE_HBA[%d] - Disabled pSCSI HBA Passthrough"
127                         " %s\n", hba->hba_id, (sh->hostt->name) ?
128                         (sh->hostt->name) : "Unknown");
129
130                 scsi_host_put(sh);
131                 return 0;
132         }
133         /*
134          * Otherwise, locate struct Scsi_Host from the original passed
135          * pSCSI Host ID and enable for phba mode
136          */
137         sh = scsi_host_lookup(phv->phv_host_id);
138         if (!sh) {
139                 pr_err("pSCSI: Unable to locate SCSI Host for"
140                         " phv_host_id: %d\n", phv->phv_host_id);
141                 return -EINVAL;
142         }
143
144         phv->phv_lld_host = sh;
145         phv->phv_mode = PHV_LLD_SCSI_HOST_NO;
146
147         pr_debug("CORE_HBA[%d] - Enabled pSCSI HBA Passthrough %s\n",
148                 hba->hba_id, (sh->hostt->name) ? (sh->hostt->name) : "Unknown");
149
150         return 1;
151 }
152
153 static void pscsi_tape_read_blocksize(struct se_device *dev,
154                 struct scsi_device *sdev)
155 {
156         unsigned char cdb[MAX_COMMAND_SIZE], *buf;
157         int ret;
158
159         buf = kzalloc(12, GFP_KERNEL);
160         if (!buf)
161                 return;
162
163         memset(cdb, 0, MAX_COMMAND_SIZE);
164         cdb[0] = MODE_SENSE;
165         cdb[4] = 0x0c; /* 12 bytes */
166
167         ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf, 12, NULL,
168                         HZ, 1, NULL);
169         if (ret)
170                 goto out_free;
171
172         /*
173          * If MODE_SENSE still returns zero, set the default value to 1024.
174          */
175         sdev->sector_size = (buf[9] << 16) | (buf[10] << 8) | (buf[11]);
176         if (!sdev->sector_size)
177                 sdev->sector_size = 1024;
178 out_free:
179         kfree(buf);
180 }
181
182 static void
183 pscsi_set_inquiry_info(struct scsi_device *sdev, struct t10_wwn *wwn)
184 {
185         unsigned char *buf;
186
187         if (sdev->inquiry_len < INQUIRY_LEN)
188                 return;
189
190         buf = sdev->inquiry;
191         if (!buf)
192                 return;
193         /*
194          * Use sdev->inquiry from drivers/scsi/scsi_scan.c:scsi_alloc_sdev()
195          */
196         memcpy(&wwn->vendor[0], &buf[8], sizeof(wwn->vendor));
197         memcpy(&wwn->model[0], &buf[16], sizeof(wwn->model));
198         memcpy(&wwn->revision[0], &buf[32], sizeof(wwn->revision));
199 }
200
201 static int
202 pscsi_get_inquiry_vpd_serial(struct scsi_device *sdev, struct t10_wwn *wwn)
203 {
204         unsigned char cdb[MAX_COMMAND_SIZE], *buf;
205         int ret;
206
207         buf = kzalloc(INQUIRY_VPD_SERIAL_LEN, GFP_KERNEL);
208         if (!buf)
209                 return -ENOMEM;
210
211         memset(cdb, 0, MAX_COMMAND_SIZE);
212         cdb[0] = INQUIRY;
213         cdb[1] = 0x01; /* Query VPD */
214         cdb[2] = 0x80; /* Unit Serial Number */
215         cdb[3] = (INQUIRY_VPD_SERIAL_LEN >> 8) & 0xff;
216         cdb[4] = (INQUIRY_VPD_SERIAL_LEN & 0xff);
217
218         ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf,
219                               INQUIRY_VPD_SERIAL_LEN, NULL, HZ, 1, NULL);
220         if (ret)
221                 goto out_free;
222
223         snprintf(&wwn->unit_serial[0], INQUIRY_VPD_SERIAL_LEN, "%s", &buf[4]);
224
225         wwn->t10_dev->dev_flags |= DF_FIRMWARE_VPD_UNIT_SERIAL;
226
227         kfree(buf);
228         return 0;
229
230 out_free:
231         kfree(buf);
232         return -EPERM;
233 }
234
235 static void
236 pscsi_get_inquiry_vpd_device_ident(struct scsi_device *sdev,
237                 struct t10_wwn *wwn)
238 {
239         unsigned char cdb[MAX_COMMAND_SIZE], *buf, *page_83;
240         int ident_len, page_len, off = 4, ret;
241         struct t10_vpd *vpd;
242
243         buf = kzalloc(INQUIRY_VPD_SERIAL_LEN, GFP_KERNEL);
244         if (!buf)
245                 return;
246
247         memset(cdb, 0, MAX_COMMAND_SIZE);
248         cdb[0] = INQUIRY;
249         cdb[1] = 0x01; /* Query VPD */
250         cdb[2] = 0x83; /* Device Identifier */
251         cdb[3] = (INQUIRY_VPD_DEVICE_IDENTIFIER_LEN >> 8) & 0xff;
252         cdb[4] = (INQUIRY_VPD_DEVICE_IDENTIFIER_LEN & 0xff);
253
254         ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf,
255                               INQUIRY_VPD_DEVICE_IDENTIFIER_LEN,
256                               NULL, HZ, 1, NULL);
257         if (ret)
258                 goto out;
259
260         page_len = (buf[2] << 8) | buf[3];
261         while (page_len > 0) {
262                 /* Grab a pointer to the Identification descriptor */
263                 page_83 = &buf[off];
264                 ident_len = page_83[3];
265                 if (!ident_len) {
266                         pr_err("page_83[3]: identifier"
267                                         " length zero!\n");
268                         break;
269                 }
270                 pr_debug("T10 VPD Identifier Length: %d\n", ident_len);
271
272                 vpd = kzalloc(sizeof(struct t10_vpd), GFP_KERNEL);
273                 if (!vpd) {
274                         pr_err("Unable to allocate memory for"
275                                         " struct t10_vpd\n");
276                         goto out;
277                 }
278                 INIT_LIST_HEAD(&vpd->vpd_list);
279
280                 transport_set_vpd_proto_id(vpd, page_83);
281                 transport_set_vpd_assoc(vpd, page_83);
282
283                 if (transport_set_vpd_ident_type(vpd, page_83) < 0) {
284                         off += (ident_len + 4);
285                         page_len -= (ident_len + 4);
286                         kfree(vpd);
287                         continue;
288                 }
289                 if (transport_set_vpd_ident(vpd, page_83) < 0) {
290                         off += (ident_len + 4);
291                         page_len -= (ident_len + 4);
292                         kfree(vpd);
293                         continue;
294                 }
295
296                 list_add_tail(&vpd->vpd_list, &wwn->t10_vpd_list);
297                 off += (ident_len + 4);
298                 page_len -= (ident_len + 4);
299         }
300
301 out:
302         kfree(buf);
303 }
304
305 static int pscsi_add_device_to_list(struct se_device *dev,
306                 struct scsi_device *sd)
307 {
308         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
309         struct request_queue *q = sd->request_queue;
310
311         pdv->pdv_sd = sd;
312
313         if (!sd->queue_depth) {
314                 sd->queue_depth = PSCSI_DEFAULT_QUEUEDEPTH;
315
316                 pr_err("Set broken SCSI Device %d:%d:%llu"
317                         " queue_depth to %d\n", sd->channel, sd->id,
318                                 sd->lun, sd->queue_depth);
319         }
320
321         dev->dev_attrib.hw_block_size = sd->sector_size;
322         dev->dev_attrib.hw_max_sectors =
323                 min_t(int, sd->host->max_sectors, queue_max_hw_sectors(q));
324         dev->dev_attrib.hw_queue_depth = sd->queue_depth;
325
326         /*
327          * Setup our standard INQUIRY info into se_dev->t10_wwn
328          */
329         pscsi_set_inquiry_info(sd, &dev->t10_wwn);
330
331         /*
332          * Locate VPD WWN Information used for various purposes within
333          * the Storage Engine.
334          */
335         if (!pscsi_get_inquiry_vpd_serial(sd, &dev->t10_wwn)) {
336                 /*
337                  * If VPD Unit Serial returned GOOD status, try
338                  * VPD Device Identification page (0x83).
339                  */
340                 pscsi_get_inquiry_vpd_device_ident(sd, &dev->t10_wwn);
341         }
342
343         /*
344          * For TYPE_TAPE, attempt to determine blocksize with MODE_SENSE.
345          */
346         if (sd->type == TYPE_TAPE)
347                 pscsi_tape_read_blocksize(dev, sd);
348         return 0;
349 }
350
351 static struct se_device *pscsi_alloc_device(struct se_hba *hba,
352                 const char *name)
353 {
354         struct pscsi_dev_virt *pdv;
355
356         pdv = kzalloc(sizeof(struct pscsi_dev_virt), GFP_KERNEL);
357         if (!pdv) {
358                 pr_err("Unable to allocate memory for struct pscsi_dev_virt\n");
359                 return NULL;
360         }
361
362         pr_debug("PSCSI: Allocated pdv: %p for %s\n", pdv, name);
363         return &pdv->dev;
364 }
365
366 /*
367  * Called with struct Scsi_Host->host_lock called.
368  */
369 static int pscsi_create_type_disk(struct se_device *dev, struct scsi_device *sd)
370         __releases(sh->host_lock)
371 {
372         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
373         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
374         struct Scsi_Host *sh = sd->host;
375         struct block_device *bd;
376         int ret;
377
378         if (scsi_device_get(sd)) {
379                 pr_err("scsi_device_get() failed for %d:%d:%d:%llu\n",
380                         sh->host_no, sd->channel, sd->id, sd->lun);
381                 spin_unlock_irq(sh->host_lock);
382                 return -EIO;
383         }
384         spin_unlock_irq(sh->host_lock);
385         /*
386          * Claim exclusive struct block_device access to struct scsi_device
387          * for TYPE_DISK using supplied udev_path
388          */
389         bd = blkdev_get_by_path(dev->udev_path,
390                                 FMODE_WRITE|FMODE_READ|FMODE_EXCL, pdv);
391         if (IS_ERR(bd)) {
392                 pr_err("pSCSI: blkdev_get_by_path() failed\n");
393                 scsi_device_put(sd);
394                 return PTR_ERR(bd);
395         }
396         pdv->pdv_bd = bd;
397
398         ret = pscsi_add_device_to_list(dev, sd);
399         if (ret) {
400                 blkdev_put(pdv->pdv_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL);
401                 scsi_device_put(sd);
402                 return ret;
403         }
404
405         pr_debug("CORE_PSCSI[%d] - Added TYPE_DISK for %d:%d:%d:%llu\n",
406                 phv->phv_host_id, sh->host_no, sd->channel, sd->id, sd->lun);
407         return 0;
408 }
409
410 /*
411  * Called with struct Scsi_Host->host_lock called.
412  */
413 static int pscsi_create_type_rom(struct se_device *dev, struct scsi_device *sd)
414         __releases(sh->host_lock)
415 {
416         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
417         struct Scsi_Host *sh = sd->host;
418         int ret;
419
420         if (scsi_device_get(sd)) {
421                 pr_err("scsi_device_get() failed for %d:%d:%d:%llu\n",
422                         sh->host_no, sd->channel, sd->id, sd->lun);
423                 spin_unlock_irq(sh->host_lock);
424                 return -EIO;
425         }
426         spin_unlock_irq(sh->host_lock);
427
428         ret = pscsi_add_device_to_list(dev, sd);
429         if (ret) {
430                 scsi_device_put(sd);
431                 return ret;
432         }
433         pr_debug("CORE_PSCSI[%d] - Added Type: %s for %d:%d:%d:%llu\n",
434                 phv->phv_host_id, scsi_device_type(sd->type), sh->host_no,
435                 sd->channel, sd->id, sd->lun);
436
437         return 0;
438 }
439
440 /*
441  * Called with struct Scsi_Host->host_lock called.
442  */
443 static int pscsi_create_type_other(struct se_device *dev,
444                 struct scsi_device *sd)
445         __releases(sh->host_lock)
446 {
447         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
448         struct Scsi_Host *sh = sd->host;
449         int ret;
450
451         spin_unlock_irq(sh->host_lock);
452         ret = pscsi_add_device_to_list(dev, sd);
453         if (ret)
454                 return ret;
455
456         pr_debug("CORE_PSCSI[%d] - Added Type: %s for %d:%d:%d:%llu\n",
457                 phv->phv_host_id, scsi_device_type(sd->type), sh->host_no,
458                 sd->channel, sd->id, sd->lun);
459         return 0;
460 }
461
462 static int pscsi_configure_device(struct se_device *dev)
463 {
464         struct se_hba *hba = dev->se_hba;
465         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
466         struct scsi_device *sd;
467         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
468         struct Scsi_Host *sh = phv->phv_lld_host;
469         int legacy_mode_enable = 0;
470         int ret;
471
472         if (!(pdv->pdv_flags & PDF_HAS_CHANNEL_ID) ||
473             !(pdv->pdv_flags & PDF_HAS_TARGET_ID) ||
474             !(pdv->pdv_flags & PDF_HAS_LUN_ID)) {
475                 pr_err("Missing scsi_channel_id=, scsi_target_id= and"
476                         " scsi_lun_id= parameters\n");
477                 return -EINVAL;
478         }
479
480         /*
481          * If not running in PHV_LLD_SCSI_HOST_NO mode, locate the
482          * struct Scsi_Host we will need to bring the TCM/pSCSI object online
483          */
484         if (!sh) {
485                 if (phv->phv_mode == PHV_LLD_SCSI_HOST_NO) {
486                         pr_err("pSCSI: Unable to locate struct"
487                                 " Scsi_Host for PHV_LLD_SCSI_HOST_NO\n");
488                         return -ENODEV;
489                 }
490                 /*
491                  * For the newer PHV_VIRTUAL_HOST_ID struct scsi_device
492                  * reference, we enforce that udev_path has been set
493                  */
494                 if (!(dev->dev_flags & DF_USING_UDEV_PATH)) {
495                         pr_err("pSCSI: udev_path attribute has not"
496                                 " been set before ENABLE=1\n");
497                         return -EINVAL;
498                 }
499                 /*
500                  * If no scsi_host_id= was passed for PHV_VIRTUAL_HOST_ID,
501                  * use the original TCM hba ID to reference Linux/SCSI Host No
502                  * and enable for PHV_LLD_SCSI_HOST_NO mode.
503                  */
504                 if (!(pdv->pdv_flags & PDF_HAS_VIRT_HOST_ID)) {
505                         if (hba->dev_count) {
506                                 pr_err("pSCSI: Unable to set hba_mode"
507                                         " with active devices\n");
508                                 return -EEXIST;
509                         }
510
511                         if (pscsi_pmode_enable_hba(hba, 1) != 1)
512                                 return -ENODEV;
513
514                         legacy_mode_enable = 1;
515                         hba->hba_flags |= HBA_FLAGS_PSCSI_MODE;
516                         sh = phv->phv_lld_host;
517                 } else {
518                         sh = scsi_host_lookup(pdv->pdv_host_id);
519                         if (!sh) {
520                                 pr_err("pSCSI: Unable to locate"
521                                         " pdv_host_id: %d\n", pdv->pdv_host_id);
522                                 return -EINVAL;
523                         }
524                         pdv->pdv_lld_host = sh;
525                 }
526         } else {
527                 if (phv->phv_mode == PHV_VIRTUAL_HOST_ID) {
528                         pr_err("pSCSI: PHV_VIRTUAL_HOST_ID set while"
529                                 " struct Scsi_Host exists\n");
530                         return -EEXIST;
531                 }
532         }
533
534         spin_lock_irq(sh->host_lock);
535         list_for_each_entry(sd, &sh->__devices, siblings) {
536                 if ((pdv->pdv_channel_id != sd->channel) ||
537                     (pdv->pdv_target_id != sd->id) ||
538                     (pdv->pdv_lun_id != sd->lun))
539                         continue;
540                 /*
541                  * Functions will release the held struct scsi_host->host_lock
542                  * before calling calling pscsi_add_device_to_list() to register
543                  * struct scsi_device with target_core_mod.
544                  */
545                 switch (sd->type) {
546                 case TYPE_DISK:
547                         ret = pscsi_create_type_disk(dev, sd);
548                         break;
549                 case TYPE_ROM:
550                         ret = pscsi_create_type_rom(dev, sd);
551                         break;
552                 default:
553                         ret = pscsi_create_type_other(dev, sd);
554                         break;
555                 }
556
557                 if (ret) {
558                         if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
559                                 scsi_host_put(sh);
560                         else if (legacy_mode_enable) {
561                                 pscsi_pmode_enable_hba(hba, 0);
562                                 hba->hba_flags &= ~HBA_FLAGS_PSCSI_MODE;
563                         }
564                         pdv->pdv_sd = NULL;
565                         return ret;
566                 }
567                 return 0;
568         }
569         spin_unlock_irq(sh->host_lock);
570
571         pr_err("pSCSI: Unable to locate %d:%d:%d:%d\n", sh->host_no,
572                 pdv->pdv_channel_id,  pdv->pdv_target_id, pdv->pdv_lun_id);
573
574         if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
575                 scsi_host_put(sh);
576         else if (legacy_mode_enable) {
577                 pscsi_pmode_enable_hba(hba, 0);
578                 hba->hba_flags &= ~HBA_FLAGS_PSCSI_MODE;
579         }
580
581         return -ENODEV;
582 }
583
584 static void pscsi_free_device(struct se_device *dev)
585 {
586         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
587         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
588         struct scsi_device *sd = pdv->pdv_sd;
589
590         if (sd) {
591                 /*
592                  * Release exclusive pSCSI internal struct block_device claim for
593                  * struct scsi_device with TYPE_DISK from pscsi_create_type_disk()
594                  */
595                 if ((sd->type == TYPE_DISK) && pdv->pdv_bd) {
596                         blkdev_put(pdv->pdv_bd,
597                                    FMODE_WRITE|FMODE_READ|FMODE_EXCL);
598                         pdv->pdv_bd = NULL;
599                 }
600                 /*
601                  * For HBA mode PHV_LLD_SCSI_HOST_NO, release the reference
602                  * to struct Scsi_Host now.
603                  */
604                 if ((phv->phv_mode == PHV_LLD_SCSI_HOST_NO) &&
605                     (phv->phv_lld_host != NULL))
606                         scsi_host_put(phv->phv_lld_host);
607                 else if (pdv->pdv_lld_host)
608                         scsi_host_put(pdv->pdv_lld_host);
609
610                 if ((sd->type == TYPE_DISK) || (sd->type == TYPE_ROM))
611                         scsi_device_put(sd);
612
613                 pdv->pdv_sd = NULL;
614         }
615
616         kfree(pdv);
617 }
618
619 static void pscsi_transport_complete(struct se_cmd *cmd, struct scatterlist *sg,
620                                      unsigned char *sense_buffer)
621 {
622         struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
623         struct scsi_device *sd = pdv->pdv_sd;
624         int result;
625         struct pscsi_plugin_task *pt = cmd->priv;
626         unsigned char *cdb;
627         /*
628          * Special case for REPORT_LUNs handling where pscsi_plugin_task has
629          * not been allocated because TCM is handling the emulation directly.
630          */
631         if (!pt)
632                 return;
633
634         cdb = &pt->pscsi_cdb[0];
635         result = pt->pscsi_result;
636         /*
637          * Hack to make sure that Write-Protect modepage is set if R/O mode is
638          * forced.
639          */
640         if (!cmd->se_deve || !cmd->data_length)
641                 goto after_mode_sense;
642
643         if (((cdb[0] == MODE_SENSE) || (cdb[0] == MODE_SENSE_10)) &&
644              (status_byte(result) << 1) == SAM_STAT_GOOD) {
645                 if (cmd->se_deve->lun_flags & TRANSPORT_LUNFLAGS_READ_ONLY) {
646                         unsigned char *buf;
647
648                         buf = transport_kmap_data_sg(cmd);
649                         if (!buf)
650                                 ; /* XXX: TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE */
651
652                         if (cdb[0] == MODE_SENSE_10) {
653                                 if (!(buf[3] & 0x80))
654                                         buf[3] |= 0x80;
655                         } else {
656                                 if (!(buf[2] & 0x80))
657                                         buf[2] |= 0x80;
658                         }
659
660                         transport_kunmap_data_sg(cmd);
661                 }
662         }
663 after_mode_sense:
664
665         if (sd->type != TYPE_TAPE || !cmd->data_length)
666                 goto after_mode_select;
667
668         /*
669          * Hack to correctly obtain the initiator requested blocksize for
670          * TYPE_TAPE.  Since this value is dependent upon each tape media,
671          * struct scsi_device->sector_size will not contain the correct value
672          * by default, so we go ahead and set it so
673          * TRANSPORT(dev)->get_blockdev() returns the correct value to the
674          * storage engine.
675          */
676         if (((cdb[0] == MODE_SELECT) || (cdb[0] == MODE_SELECT_10)) &&
677               (status_byte(result) << 1) == SAM_STAT_GOOD) {
678                 unsigned char *buf;
679                 u16 bdl;
680                 u32 blocksize;
681
682                 buf = sg_virt(&sg[0]);
683                 if (!buf) {
684                         pr_err("Unable to get buf for scatterlist\n");
685                         goto after_mode_select;
686                 }
687
688                 if (cdb[0] == MODE_SELECT)
689                         bdl = (buf[3]);
690                 else
691                         bdl = (buf[6] << 8) | (buf[7]);
692
693                 if (!bdl)
694                         goto after_mode_select;
695
696                 if (cdb[0] == MODE_SELECT)
697                         blocksize = (buf[9] << 16) | (buf[10] << 8) |
698                                         (buf[11]);
699                 else
700                         blocksize = (buf[13] << 16) | (buf[14] << 8) |
701                                         (buf[15]);
702
703                 sd->sector_size = blocksize;
704         }
705 after_mode_select:
706
707         if (sense_buffer && (status_byte(result) & CHECK_CONDITION)) {
708                 memcpy(sense_buffer, pt->pscsi_sense, TRANSPORT_SENSE_BUFFER);
709                 cmd->se_cmd_flags |= SCF_TRANSPORT_TASK_SENSE;
710         }
711 }
712
713 enum {
714         Opt_scsi_host_id, Opt_scsi_channel_id, Opt_scsi_target_id,
715         Opt_scsi_lun_id, Opt_err
716 };
717
718 static match_table_t tokens = {
719         {Opt_scsi_host_id, "scsi_host_id=%d"},
720         {Opt_scsi_channel_id, "scsi_channel_id=%d"},
721         {Opt_scsi_target_id, "scsi_target_id=%d"},
722         {Opt_scsi_lun_id, "scsi_lun_id=%d"},
723         {Opt_err, NULL}
724 };
725
726 static ssize_t pscsi_set_configfs_dev_params(struct se_device *dev,
727                 const char *page, ssize_t count)
728 {
729         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
730         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
731         char *orig, *ptr, *opts;
732         substring_t args[MAX_OPT_ARGS];
733         int ret = 0, arg, token;
734
735         opts = kstrdup(page, GFP_KERNEL);
736         if (!opts)
737                 return -ENOMEM;
738
739         orig = opts;
740
741         while ((ptr = strsep(&opts, ",\n")) != NULL) {
742                 if (!*ptr)
743                         continue;
744
745                 token = match_token(ptr, tokens, args);
746                 switch (token) {
747                 case Opt_scsi_host_id:
748                         if (phv->phv_mode == PHV_LLD_SCSI_HOST_NO) {
749                                 pr_err("PSCSI[%d]: Unable to accept"
750                                         " scsi_host_id while phv_mode =="
751                                         " PHV_LLD_SCSI_HOST_NO\n",
752                                         phv->phv_host_id);
753                                 ret = -EINVAL;
754                                 goto out;
755                         }
756                         ret = match_int(args, &arg);
757                         if (ret)
758                                 goto out;
759                         pdv->pdv_host_id = arg;
760                         pr_debug("PSCSI[%d]: Referencing SCSI Host ID:"
761                                 " %d\n", phv->phv_host_id, pdv->pdv_host_id);
762                         pdv->pdv_flags |= PDF_HAS_VIRT_HOST_ID;
763                         break;
764                 case Opt_scsi_channel_id:
765                         ret = match_int(args, &arg);
766                         if (ret)
767                                 goto out;
768                         pdv->pdv_channel_id = arg;
769                         pr_debug("PSCSI[%d]: Referencing SCSI Channel"
770                                 " ID: %d\n",  phv->phv_host_id,
771                                 pdv->pdv_channel_id);
772                         pdv->pdv_flags |= PDF_HAS_CHANNEL_ID;
773                         break;
774                 case Opt_scsi_target_id:
775                         ret = match_int(args, &arg);
776                         if (ret)
777                                 goto out;
778                         pdv->pdv_target_id = arg;
779                         pr_debug("PSCSI[%d]: Referencing SCSI Target"
780                                 " ID: %d\n", phv->phv_host_id,
781                                 pdv->pdv_target_id);
782                         pdv->pdv_flags |= PDF_HAS_TARGET_ID;
783                         break;
784                 case Opt_scsi_lun_id:
785                         ret = match_int(args, &arg);
786                         if (ret)
787                                 goto out;
788                         pdv->pdv_lun_id = arg;
789                         pr_debug("PSCSI[%d]: Referencing SCSI LUN ID:"
790                                 " %d\n", phv->phv_host_id, pdv->pdv_lun_id);
791                         pdv->pdv_flags |= PDF_HAS_LUN_ID;
792                         break;
793                 default:
794                         break;
795                 }
796         }
797
798 out:
799         kfree(orig);
800         return (!ret) ? count : ret;
801 }
802
803 static ssize_t pscsi_show_configfs_dev_params(struct se_device *dev, char *b)
804 {
805         struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
806         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
807         struct scsi_device *sd = pdv->pdv_sd;
808         unsigned char host_id[16];
809         ssize_t bl;
810         int i;
811
812         if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
813                 snprintf(host_id, 16, "%d", pdv->pdv_host_id);
814         else
815                 snprintf(host_id, 16, "PHBA Mode");
816
817         bl = sprintf(b, "SCSI Device Bus Location:"
818                 " Channel ID: %d Target ID: %d LUN: %d Host ID: %s\n",
819                 pdv->pdv_channel_id, pdv->pdv_target_id, pdv->pdv_lun_id,
820                 host_id);
821
822         if (sd) {
823                 bl += sprintf(b + bl, "        ");
824                 bl += sprintf(b + bl, "Vendor: ");
825                 for (i = 0; i < 8; i++) {
826                         if (ISPRINT(sd->vendor[i]))   /* printable character? */
827                                 bl += sprintf(b + bl, "%c", sd->vendor[i]);
828                         else
829                                 bl += sprintf(b + bl, " ");
830                 }
831                 bl += sprintf(b + bl, " Model: ");
832                 for (i = 0; i < 16; i++) {
833                         if (ISPRINT(sd->model[i]))   /* printable character ? */
834                                 bl += sprintf(b + bl, "%c", sd->model[i]);
835                         else
836                                 bl += sprintf(b + bl, " ");
837                 }
838                 bl += sprintf(b + bl, " Rev: ");
839                 for (i = 0; i < 4; i++) {
840                         if (ISPRINT(sd->rev[i]))   /* printable character ? */
841                                 bl += sprintf(b + bl, "%c", sd->rev[i]);
842                         else
843                                 bl += sprintf(b + bl, " ");
844                 }
845                 bl += sprintf(b + bl, "\n");
846         }
847         return bl;
848 }
849
850 static void pscsi_bi_endio(struct bio *bio, int error)
851 {
852         bio_put(bio);
853 }
854
855 static inline struct bio *pscsi_get_bio(int nr_vecs)
856 {
857         struct bio *bio;
858         /*
859          * Use bio_malloc() following the comment in for bio -> struct request
860          * in block/blk-core.c:blk_make_request()
861          */
862         bio = bio_kmalloc(GFP_KERNEL, nr_vecs);
863         if (!bio) {
864                 pr_err("PSCSI: bio_kmalloc() failed\n");
865                 return NULL;
866         }
867         bio->bi_end_io = pscsi_bi_endio;
868
869         return bio;
870 }
871
872 static sense_reason_t
873 pscsi_map_sg(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
874                 enum dma_data_direction data_direction, struct bio **hbio)
875 {
876         struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
877         struct bio *bio = NULL, *tbio = NULL;
878         struct page *page;
879         struct scatterlist *sg;
880         u32 data_len = cmd->data_length, i, len, bytes, off;
881         int nr_pages = (cmd->data_length + sgl[0].offset +
882                         PAGE_SIZE - 1) >> PAGE_SHIFT;
883         int nr_vecs = 0, rc;
884         int rw = (data_direction == DMA_TO_DEVICE);
885
886         *hbio = NULL;
887
888         pr_debug("PSCSI: nr_pages: %d\n", nr_pages);
889
890         for_each_sg(sgl, sg, sgl_nents, i) {
891                 page = sg_page(sg);
892                 off = sg->offset;
893                 len = sg->length;
894
895                 pr_debug("PSCSI: i: %d page: %p len: %d off: %d\n", i,
896                         page, len, off);
897
898                 /*
899                  * We only have one page of data in each sg element,
900                  * we can not cross a page boundary.
901                  */
902                 if (off + len > PAGE_SIZE)
903                         goto fail;
904
905                 if (len > 0 && data_len > 0) {
906                         bytes = min_t(unsigned int, len, PAGE_SIZE - off);
907                         bytes = min(bytes, data_len);
908
909                         if (!bio) {
910                                 nr_vecs = min_t(int, BIO_MAX_PAGES, nr_pages);
911                                 nr_pages -= nr_vecs;
912                                 /*
913                                  * Calls bio_kmalloc() and sets bio->bi_end_io()
914                                  */
915                                 bio = pscsi_get_bio(nr_vecs);
916                                 if (!bio)
917                                         goto fail;
918
919                                 if (rw)
920                                         bio->bi_rw |= REQ_WRITE;
921
922                                 pr_debug("PSCSI: Allocated bio: %p,"
923                                         " dir: %s nr_vecs: %d\n", bio,
924                                         (rw) ? "rw" : "r", nr_vecs);
925                                 /*
926                                  * Set *hbio pointer to handle the case:
927                                  * nr_pages > BIO_MAX_PAGES, where additional
928                                  * bios need to be added to complete a given
929                                  * command.
930                                  */
931                                 if (!*hbio)
932                                         *hbio = tbio = bio;
933                                 else
934                                         tbio = tbio->bi_next = bio;
935                         }
936
937                         pr_debug("PSCSI: Calling bio_add_pc_page() i: %d"
938                                 " bio: %p page: %p len: %d off: %d\n", i, bio,
939                                 page, len, off);
940
941                         rc = bio_add_pc_page(pdv->pdv_sd->request_queue,
942                                         bio, page, bytes, off);
943                         if (rc != bytes)
944                                 goto fail;
945
946                         pr_debug("PSCSI: bio->bi_vcnt: %d nr_vecs: %d\n",
947                                 bio->bi_vcnt, nr_vecs);
948
949                         if (bio->bi_vcnt > nr_vecs) {
950                                 pr_debug("PSCSI: Reached bio->bi_vcnt max:"
951                                         " %d i: %d bio: %p, allocating another"
952                                         " bio\n", bio->bi_vcnt, i, bio);
953                                 /*
954                                  * Clear the pointer so that another bio will
955                                  * be allocated with pscsi_get_bio() above, the
956                                  * current bio has already been set *tbio and
957                                  * bio->bi_next.
958                                  */
959                                 bio = NULL;
960                         }
961
962                         data_len -= bytes;
963                 }
964         }
965
966         return 0;
967 fail:
968         while (*hbio) {
969                 bio = *hbio;
970                 *hbio = (*hbio)->bi_next;
971                 bio_endio(bio, 0);      /* XXX: should be error */
972         }
973         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
974 }
975
976 static sense_reason_t
977 pscsi_parse_cdb(struct se_cmd *cmd)
978 {
979         if (cmd->se_cmd_flags & SCF_BIDI)
980                 return TCM_UNSUPPORTED_SCSI_OPCODE;
981
982         return passthrough_parse_cdb(cmd, pscsi_execute_cmd);
983 }
984
985 static sense_reason_t
986 pscsi_execute_cmd(struct se_cmd *cmd)
987 {
988         struct scatterlist *sgl = cmd->t_data_sg;
989         u32 sgl_nents = cmd->t_data_nents;
990         enum dma_data_direction data_direction = cmd->data_direction;
991         struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
992         struct pscsi_plugin_task *pt;
993         struct request *req;
994         struct bio *hbio;
995         sense_reason_t ret;
996
997         /*
998          * Dynamically alloc cdb space, since it may be larger than
999          * TCM_MAX_COMMAND_SIZE
1000          */
1001         pt = kzalloc(sizeof(*pt) + scsi_command_size(cmd->t_task_cdb), GFP_KERNEL);
1002         if (!pt) {
1003                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1004         }
1005         cmd->priv = pt;
1006
1007         memcpy(pt->pscsi_cdb, cmd->t_task_cdb,
1008                 scsi_command_size(cmd->t_task_cdb));
1009
1010         if (!sgl) {
1011                 req = blk_get_request(pdv->pdv_sd->request_queue,
1012                                 (data_direction == DMA_TO_DEVICE),
1013                                 GFP_KERNEL);
1014                 if (IS_ERR(req)) {
1015                         pr_err("PSCSI: blk_get_request() failed\n");
1016                         ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1017                         goto fail;
1018                 }
1019
1020                 blk_rq_set_block_pc(req);
1021         } else {
1022                 BUG_ON(!cmd->data_length);
1023
1024                 ret = pscsi_map_sg(cmd, sgl, sgl_nents, data_direction, &hbio);
1025                 if (ret)
1026                         goto fail;
1027
1028                 req = blk_make_request(pdv->pdv_sd->request_queue, hbio,
1029                                        GFP_KERNEL);
1030                 if (IS_ERR(req)) {
1031                         pr_err("pSCSI: blk_make_request() failed\n");
1032                         ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1033                         goto fail_free_bio;
1034                 }
1035         }
1036
1037         req->end_io = pscsi_req_done;
1038         req->end_io_data = cmd;
1039         req->cmd_len = scsi_command_size(pt->pscsi_cdb);
1040         req->cmd = &pt->pscsi_cdb[0];
1041         req->sense = &pt->pscsi_sense[0];
1042         req->sense_len = 0;
1043         if (pdv->pdv_sd->type == TYPE_DISK)
1044                 req->timeout = PS_TIMEOUT_DISK;
1045         else
1046                 req->timeout = PS_TIMEOUT_OTHER;
1047         req->retries = PS_RETRY;
1048
1049         blk_execute_rq_nowait(pdv->pdv_sd->request_queue, NULL, req,
1050                         (cmd->sam_task_attr == TCM_HEAD_TAG),
1051                         pscsi_req_done);
1052
1053         return 0;
1054
1055 fail_free_bio:
1056         while (hbio) {
1057                 struct bio *bio = hbio;
1058                 hbio = hbio->bi_next;
1059                 bio_endio(bio, 0);      /* XXX: should be error */
1060         }
1061         ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1062 fail:
1063         kfree(pt);
1064         return ret;
1065 }
1066
1067 /*      pscsi_get_device_type():
1068  *
1069  *
1070  */
1071 static u32 pscsi_get_device_type(struct se_device *dev)
1072 {
1073         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
1074         struct scsi_device *sd = pdv->pdv_sd;
1075
1076         return (sd) ? sd->type : TYPE_NO_LUN;
1077 }
1078
1079 static sector_t pscsi_get_blocks(struct se_device *dev)
1080 {
1081         struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
1082
1083         if (pdv->pdv_bd && pdv->pdv_bd->bd_part)
1084                 return pdv->pdv_bd->bd_part->nr_sects;
1085
1086         dump_stack();
1087         return 0;
1088 }
1089
1090 static void pscsi_req_done(struct request *req, int uptodate)
1091 {
1092         struct se_cmd *cmd = req->end_io_data;
1093         struct pscsi_plugin_task *pt = cmd->priv;
1094
1095         pt->pscsi_result = req->errors;
1096         pt->pscsi_resid = req->resid_len;
1097
1098         cmd->scsi_status = status_byte(pt->pscsi_result) << 1;
1099         if (cmd->scsi_status) {
1100                 pr_debug("PSCSI Status Byte exception at cmd: %p CDB:"
1101                         " 0x%02x Result: 0x%08x\n", cmd, pt->pscsi_cdb[0],
1102                         pt->pscsi_result);
1103         }
1104
1105         switch (host_byte(pt->pscsi_result)) {
1106         case DID_OK:
1107                 target_complete_cmd(cmd, cmd->scsi_status);
1108                 break;
1109         default:
1110                 pr_debug("PSCSI Host Byte exception at cmd: %p CDB:"
1111                         " 0x%02x Result: 0x%08x\n", cmd, pt->pscsi_cdb[0],
1112                         pt->pscsi_result);
1113                 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
1114                 break;
1115         }
1116
1117         __blk_put_request(req->q, req);
1118         kfree(pt);
1119 }
1120
1121 DEF_TB_DEV_ATTRIB_RO(pscsi, hw_pi_prot_type);
1122 TB_DEV_ATTR_RO(pscsi, hw_pi_prot_type);
1123
1124 DEF_TB_DEV_ATTRIB_RO(pscsi, hw_block_size);
1125 TB_DEV_ATTR_RO(pscsi, hw_block_size);
1126
1127 DEF_TB_DEV_ATTRIB_RO(pscsi, hw_max_sectors);
1128 TB_DEV_ATTR_RO(pscsi, hw_max_sectors);
1129
1130 DEF_TB_DEV_ATTRIB_RO(pscsi, hw_queue_depth);
1131 TB_DEV_ATTR_RO(pscsi, hw_queue_depth);
1132
1133 static struct configfs_attribute *pscsi_backend_dev_attrs[] = {
1134         &pscsi_dev_attrib_hw_pi_prot_type.attr,
1135         &pscsi_dev_attrib_hw_block_size.attr,
1136         &pscsi_dev_attrib_hw_max_sectors.attr,
1137         &pscsi_dev_attrib_hw_queue_depth.attr,
1138         NULL,
1139 };
1140
1141 static struct se_subsystem_api pscsi_template = {
1142         .name                   = "pscsi",
1143         .owner                  = THIS_MODULE,
1144         .transport_flags        = TRANSPORT_FLAG_PASSTHROUGH,
1145         .attach_hba             = pscsi_attach_hba,
1146         .detach_hba             = pscsi_detach_hba,
1147         .pmode_enable_hba       = pscsi_pmode_enable_hba,
1148         .alloc_device           = pscsi_alloc_device,
1149         .configure_device       = pscsi_configure_device,
1150         .free_device            = pscsi_free_device,
1151         .transport_complete     = pscsi_transport_complete,
1152         .parse_cdb              = pscsi_parse_cdb,
1153         .set_configfs_dev_params = pscsi_set_configfs_dev_params,
1154         .show_configfs_dev_params = pscsi_show_configfs_dev_params,
1155         .get_device_type        = pscsi_get_device_type,
1156         .get_blocks             = pscsi_get_blocks,
1157 };
1158
1159 static int __init pscsi_module_init(void)
1160 {
1161         struct target_backend_cits *tbc = &pscsi_template.tb_cits;
1162
1163         target_core_setup_sub_cits(&pscsi_template);
1164         tbc->tb_dev_attrib_cit.ct_attrs = pscsi_backend_dev_attrs;
1165
1166         return transport_subsystem_register(&pscsi_template);
1167 }
1168
1169 static void __exit pscsi_module_exit(void)
1170 {
1171         transport_subsystem_release(&pscsi_template);
1172 }
1173
1174 MODULE_DESCRIPTION("TCM PSCSI subsystem plugin");
1175 MODULE_AUTHOR("nab@Linux-iSCSI.org");
1176 MODULE_LICENSE("GPL");
1177
1178 module_init(pscsi_module_init);
1179 module_exit(pscsi_module_exit);