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Linux 4.1.16
[linux/fpc-iii.git] / drivers / xen / xen-scsiback.c
blobb7f51504f85adc1b5d19d33e48d066bdd60684c5
1 /*
2 * Xen SCSI backend driver
3 *
4 * Copyright (c) 2008, FUJITSU Limited
5 *
6 * Based on the blkback driver code.
7 * Adaption to kernel taget core infrastructure taken from vhost/scsi.c
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License version 2
11 * as published by the Free Software Foundation; or, when distributed
12 * separately from the Linux kernel or incorporated into other
13 * software packages, subject to the following license:
14 *
15 * Permission is hereby granted, free of charge, to any person obtaining a copy
16 * of this source file (the "Software"), to deal in the Software without
17 * restriction, including without limitation the rights to use, copy, modify,
18 * merge, publish, distribute, sublicense, and/or sell copies of the Software,
19 * and to permit persons to whom the Software is furnished to do so, subject to
20 * the following conditions:
21 *
22 * The above copyright notice and this permission notice shall be included in
23 * all copies or substantial portions of the Software.
24 *
25 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
26 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
27 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
28 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
29 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
30 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
31 * IN THE SOFTWARE.
32 */
33
34 #define pr_fmt(fmt) "xen-pvscsi: " fmt
35
36 #include <stdarg.h>
37
38 #include <linux/module.h>
39 #include <linux/utsname.h>
40 #include <linux/interrupt.h>
41 #include <linux/slab.h>
42 #include <linux/wait.h>
43 #include <linux/sched.h>
44 #include <linux/list.h>
45 #include <linux/gfp.h>
46 #include <linux/delay.h>
47 #include <linux/spinlock.h>
48 #include <linux/configfs.h>
49
50 #include <generated/utsrelease.h>
51
52 #include <scsi/scsi.h>
53 #include <scsi/scsi_dbg.h>
54 #include <scsi/scsi_eh.h>
55 #include <scsi/scsi_tcq.h>
56
57 #include <target/target_core_base.h>
58 #include <target/target_core_fabric.h>
59 #include <target/target_core_configfs.h>
60 #include <target/target_core_fabric_configfs.h>
61
62 #include <asm/hypervisor.h>
63
64 #include <xen/xen.h>
65 #include <xen/balloon.h>
66 #include <xen/events.h>
67 #include <xen/xenbus.h>
68 #include <xen/grant_table.h>
69 #include <xen/page.h>
70
71 #include <xen/interface/grant_table.h>
72 #include <xen/interface/io/vscsiif.h>
73
74 #define VSCSI_VERSION "v0.1"
75 #define VSCSI_NAMELEN 32
76
77 struct ids_tuple {
78 unsigned int hst; /* host */
79 unsigned int chn; /* channel */
80 unsigned int tgt; /* target */
81 unsigned int lun; /* LUN */
82 };
83
84 struct v2p_entry {
85 struct ids_tuple v; /* translate from */
86 struct scsiback_tpg *tpg; /* translate to */
87 unsigned int lun;
88 struct kref kref;
89 struct list_head l;
90 };
91
92 struct vscsibk_info {
93 struct xenbus_device *dev;
94
95 domid_t domid;
96 unsigned int irq;
97
98 struct vscsiif_back_ring ring;
99 int ring_error;
100
101 spinlock_t ring_lock;
102 atomic_t nr_unreplied_reqs;
103
104 spinlock_t v2p_lock;
105 struct list_head v2p_entry_lists;
106
107 wait_queue_head_t waiting_to_free;
108 };
109
110 /* theoretical maximum of grants for one request */
111 #define VSCSI_MAX_GRANTS (SG_ALL + VSCSIIF_SG_TABLESIZE)
112
113 /*
114 * VSCSI_GRANT_BATCH is the maximum number of grants to be processed in one
115 * call to map/unmap grants. Don't choose it too large, as there are arrays
116 * with VSCSI_GRANT_BATCH elements allocated on the stack.
117 */
118 #define VSCSI_GRANT_BATCH 16
119
120 struct vscsibk_pend {
121 uint16_t rqid;
122
123 uint8_t cmnd[VSCSIIF_MAX_COMMAND_SIZE];
124 uint8_t cmd_len;
125
126 uint8_t sc_data_direction;
127 uint16_t n_sg; /* real length of SG list */
128 uint16_t n_grants; /* SG pages and potentially SG list */
129 uint32_t data_len;
130 uint32_t result;
131
132 struct vscsibk_info *info;
133 struct v2p_entry *v2p;
134 struct scatterlist *sgl;
135
136 uint8_t sense_buffer[VSCSIIF_SENSE_BUFFERSIZE];
137
138 grant_handle_t grant_handles[VSCSI_MAX_GRANTS];
139 struct page *pages[VSCSI_MAX_GRANTS];
140
141 struct se_cmd se_cmd;
142 };
143
144 struct scsiback_tmr {
145 atomic_t tmr_complete;
146 wait_queue_head_t tmr_wait;
147 };
148
149 struct scsiback_nexus {
150 /* Pointer to TCM session for I_T Nexus */
151 struct se_session *tvn_se_sess;
152 };
153
154 struct scsiback_tport {
155 /* SCSI protocol the tport is providing */
156 u8 tport_proto_id;
157 /* Binary World Wide unique Port Name for pvscsi Target port */
158 u64 tport_wwpn;
159 /* ASCII formatted WWPN for pvscsi Target port */
160 char tport_name[VSCSI_NAMELEN];
161 /* Returned by scsiback_make_tport() */
162 struct se_wwn tport_wwn;
163 };
164
165 struct scsiback_tpg {
166 /* scsiback port target portal group tag for TCM */
167 u16 tport_tpgt;
168 /* track number of TPG Port/Lun Links wrt explicit I_T Nexus shutdown */
169 int tv_tpg_port_count;
170 /* xen-pvscsi references to tpg_nexus, protected by tv_tpg_mutex */
171 int tv_tpg_fe_count;
172 /* list for scsiback_list */
173 struct list_head tv_tpg_list;
174 /* Used to protect access for tpg_nexus */
175 struct mutex tv_tpg_mutex;
176 /* Pointer to the TCM pvscsi I_T Nexus for this TPG endpoint */
177 struct scsiback_nexus *tpg_nexus;
178 /* Pointer back to scsiback_tport */
179 struct scsiback_tport *tport;
180 /* Returned by scsiback_make_tpg() */
181 struct se_portal_group se_tpg;
182 /* alias used in xenstore */
183 char param_alias[VSCSI_NAMELEN];
184 /* list of info structures related to this target portal group */
185 struct list_head info_list;
186 };
187
188 #define SCSIBACK_INVALID_HANDLE (~0)
189
190 static bool log_print_stat;
191 module_param(log_print_stat, bool, 0644);
192
193 static int scsiback_max_buffer_pages = 1024;
194 module_param_named(max_buffer_pages, scsiback_max_buffer_pages, int, 0644);
195 MODULE_PARM_DESC(max_buffer_pages,
196 "Maximum number of free pages to keep in backend buffer");
197
198 static struct kmem_cache *scsiback_cachep;
199 static DEFINE_SPINLOCK(free_pages_lock);
200 static int free_pages_num;
201 static LIST_HEAD(scsiback_free_pages);
202
203 /* Global spinlock to protect scsiback TPG list */
204 static DEFINE_MUTEX(scsiback_mutex);
205 static LIST_HEAD(scsiback_list);
206
207 static const struct target_core_fabric_ops scsiback_ops;
208
209 static void scsiback_get(struct vscsibk_info *info)
210 {
211 atomic_inc(&info->nr_unreplied_reqs);
212 }
213
214 static void scsiback_put(struct vscsibk_info *info)
215 {
216 if (atomic_dec_and_test(&info->nr_unreplied_reqs))
217 wake_up(&info->waiting_to_free);
218 }
219
220 static void put_free_pages(struct page **page, int num)
221 {
222 unsigned long flags;
223 int i = free_pages_num + num, n = num;
224
225 if (num == 0)
226 return;
227 if (i > scsiback_max_buffer_pages) {
228 n = min(num, i - scsiback_max_buffer_pages);
229 gnttab_free_pages(n, page + num - n);
230 n = num - n;
231 }
232 spin_lock_irqsave(&free_pages_lock, flags);
233 for (i = 0; i < n; i++)
234 list_add(&page[i]->lru, &scsiback_free_pages);
235 free_pages_num += n;
236 spin_unlock_irqrestore(&free_pages_lock, flags);
237 }
238
239 static int get_free_page(struct page **page)
240 {
241 unsigned long flags;
242
243 spin_lock_irqsave(&free_pages_lock, flags);
244 if (list_empty(&scsiback_free_pages)) {
245 spin_unlock_irqrestore(&free_pages_lock, flags);
246 return gnttab_alloc_pages(1, page);
247 }
248 page[0] = list_first_entry(&scsiback_free_pages, struct page, lru);
249 list_del(&page[0]->lru);
250 free_pages_num--;
251 spin_unlock_irqrestore(&free_pages_lock, flags);
252 return 0;
253 }
254
255 static unsigned long vaddr_page(struct page *page)
256 {
257 unsigned long pfn = page_to_pfn(page);
258
259 return (unsigned long)pfn_to_kaddr(pfn);
260 }
261
262 static unsigned long vaddr(struct vscsibk_pend *req, int seg)
263 {
264 return vaddr_page(req->pages[seg]);
265 }
266
267 static void scsiback_print_status(char *sense_buffer, int errors,
268 struct vscsibk_pend *pending_req)
269 {
270 struct scsiback_tpg *tpg = pending_req->v2p->tpg;
271
272 pr_err("[%s:%d] cmnd[0]=%02x -> st=%02x msg=%02x host=%02x drv=%02x\n",
273 tpg->tport->tport_name, pending_req->v2p->lun,
274 pending_req->cmnd[0], status_byte(errors), msg_byte(errors),
275 host_byte(errors), driver_byte(errors));
276 }
277
278 static void scsiback_fast_flush_area(struct vscsibk_pend *req)
279 {
280 struct gnttab_unmap_grant_ref unmap[VSCSI_GRANT_BATCH];
281 struct page *pages[VSCSI_GRANT_BATCH];
282 unsigned int i, invcount = 0;
283 grant_handle_t handle;
284 int err;
285
286 kfree(req->sgl);
287 req->sgl = NULL;
288 req->n_sg = 0;
289
290 if (!req->n_grants)
291 return;
292
293 for (i = 0; i < req->n_grants; i++) {
294 handle = req->grant_handles[i];
295 if (handle == SCSIBACK_INVALID_HANDLE)
296 continue;
297 gnttab_set_unmap_op(&unmap[invcount], vaddr(req, i),
298 GNTMAP_host_map, handle);
299 req->grant_handles[i] = SCSIBACK_INVALID_HANDLE;
300 pages[invcount] = req->pages[i];
301 put_page(pages[invcount]);
302 invcount++;
303 if (invcount < VSCSI_GRANT_BATCH)
304 continue;
305 err = gnttab_unmap_refs(unmap, NULL, pages, invcount);
306 BUG_ON(err);
307 invcount = 0;
308 }
309
310 if (invcount) {
311 err = gnttab_unmap_refs(unmap, NULL, pages, invcount);
312 BUG_ON(err);
313 }
314
315 put_free_pages(req->pages, req->n_grants);
316 req->n_grants = 0;
317 }
318
319 static void scsiback_free_translation_entry(struct kref *kref)
320 {
321 struct v2p_entry *entry = container_of(kref, struct v2p_entry, kref);
322 struct scsiback_tpg *tpg = entry->tpg;
323
324 mutex_lock(&tpg->tv_tpg_mutex);
325 tpg->tv_tpg_fe_count--;
326 mutex_unlock(&tpg->tv_tpg_mutex);
327
328 kfree(entry);
329 }
330
331 static void scsiback_do_resp_with_sense(char *sense_buffer, int32_t result,
332 uint32_t resid, struct vscsibk_pend *pending_req)
333 {
334 struct vscsiif_response *ring_res;
335 struct vscsibk_info *info = pending_req->info;
336 int notify;
337 struct scsi_sense_hdr sshdr;
338 unsigned long flags;
339 unsigned len;
340
341 spin_lock_irqsave(&info->ring_lock, flags);
342
343 ring_res = RING_GET_RESPONSE(&info->ring, info->ring.rsp_prod_pvt);
344 info->ring.rsp_prod_pvt++;
345
346 ring_res->rslt = result;
347 ring_res->rqid = pending_req->rqid;
348
349 if (sense_buffer != NULL &&
350 scsi_normalize_sense(sense_buffer, VSCSIIF_SENSE_BUFFERSIZE,
351 &sshdr)) {
352 len = min_t(unsigned, 8 + sense_buffer[7],
353 VSCSIIF_SENSE_BUFFERSIZE);
354 memcpy(ring_res->sense_buffer, sense_buffer, len);
355 ring_res->sense_len = len;
356 } else {
357 ring_res->sense_len = 0;
358 }
359
360 ring_res->residual_len = resid;
361
362 RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&info->ring, notify);
363 spin_unlock_irqrestore(&info->ring_lock, flags);
364
365 if (notify)
366 notify_remote_via_irq(info->irq);
367
368 if (pending_req->v2p)
369 kref_put(&pending_req->v2p->kref,
370 scsiback_free_translation_entry);
371 }
372
373 static void scsiback_cmd_done(struct vscsibk_pend *pending_req)
374 {
375 struct vscsibk_info *info = pending_req->info;
376 unsigned char *sense_buffer;
377 unsigned int resid;
378 int errors;
379
380 sense_buffer = pending_req->sense_buffer;
381 resid = pending_req->se_cmd.residual_count;
382 errors = pending_req->result;
383
384 if (errors && log_print_stat)
385 scsiback_print_status(sense_buffer, errors, pending_req);
386
387 scsiback_fast_flush_area(pending_req);
388 scsiback_do_resp_with_sense(sense_buffer, errors, resid, pending_req);
389 scsiback_put(info);
390 }
391
392 static void scsiback_cmd_exec(struct vscsibk_pend *pending_req)
393 {
394 struct se_cmd *se_cmd = &pending_req->se_cmd;
395 struct se_session *sess = pending_req->v2p->tpg->tpg_nexus->tvn_se_sess;
396 int rc;
397
398 memset(pending_req->sense_buffer, 0, VSCSIIF_SENSE_BUFFERSIZE);
399
400 memset(se_cmd, 0, sizeof(*se_cmd));
401
402 scsiback_get(pending_req->info);
403 rc = target_submit_cmd_map_sgls(se_cmd, sess, pending_req->cmnd,
404 pending_req->sense_buffer, pending_req->v2p->lun,
405 pending_req->data_len, 0,
406 pending_req->sc_data_direction, 0,
407 pending_req->sgl, pending_req->n_sg,
408 NULL, 0, NULL, 0);
409 if (rc < 0) {
410 transport_send_check_condition_and_sense(se_cmd,
411 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
412 transport_generic_free_cmd(se_cmd, 0);
413 }
414 }
415
416 static int scsiback_gnttab_data_map_batch(struct gnttab_map_grant_ref *map,
417 struct page **pg, grant_handle_t *grant, int cnt)
418 {
419 int err, i;
420
421 if (!cnt)
422 return 0;
423
424 err = gnttab_map_refs(map, NULL, pg, cnt);
425 BUG_ON(err);
426 for (i = 0; i < cnt; i++) {
427 if (unlikely(map[i].status != GNTST_okay)) {
428 pr_err("invalid buffer -- could not remap it\n");
429 map[i].handle = SCSIBACK_INVALID_HANDLE;
430 err = -ENOMEM;
431 } else {
432 get_page(pg[i]);
433 }
434 grant[i] = map[i].handle;
435 }
436 return err;
437 }
438
439 static int scsiback_gnttab_data_map_list(struct vscsibk_pend *pending_req,
440 struct scsiif_request_segment *seg, struct page **pg,
441 grant_handle_t *grant, int cnt, u32 flags)
442 {
443 int mapcount = 0, i, err = 0;
444 struct gnttab_map_grant_ref map[VSCSI_GRANT_BATCH];
445 struct vscsibk_info *info = pending_req->info;
446
447 for (i = 0; i < cnt; i++) {
448 if (get_free_page(pg + mapcount)) {
449 put_free_pages(pg, mapcount);
450 pr_err("no grant page\n");
451 return -ENOMEM;
452 }
453 gnttab_set_map_op(&map[mapcount], vaddr_page(pg[mapcount]),
454 flags, seg[i].gref, info->domid);
455 mapcount++;
456 if (mapcount < VSCSI_GRANT_BATCH)
457 continue;
458 err = scsiback_gnttab_data_map_batch(map, pg, grant, mapcount);
459 pg += mapcount;
460 grant += mapcount;
461 pending_req->n_grants += mapcount;
462 if (err)
463 return err;
464 mapcount = 0;
465 }
466 err = scsiback_gnttab_data_map_batch(map, pg, grant, mapcount);
467 pending_req->n_grants += mapcount;
468 return err;
469 }
470
471 static int scsiback_gnttab_data_map(struct vscsiif_request *ring_req,
472 struct vscsibk_pend *pending_req)
473 {
474 u32 flags;
475 int i, err, n_segs, i_seg = 0;
476 struct page **pg;
477 struct scsiif_request_segment *seg;
478 unsigned long end_seg = 0;
479 unsigned int nr_segments = (unsigned int)ring_req->nr_segments;
480 unsigned int nr_sgl = 0;
481 struct scatterlist *sg;
482 grant_handle_t *grant;
483
484 pending_req->n_sg = 0;
485 pending_req->n_grants = 0;
486 pending_req->data_len = 0;
487
488 nr_segments &= ~VSCSIIF_SG_GRANT;
489 if (!nr_segments)
490 return 0;
491
492 if (nr_segments > VSCSIIF_SG_TABLESIZE) {
493 pr_debug("invalid parameter nr_seg = %d\n",
494 ring_req->nr_segments);
495 return -EINVAL;
496 }
497
498 if (ring_req->nr_segments & VSCSIIF_SG_GRANT) {
499 err = scsiback_gnttab_data_map_list(pending_req, ring_req->seg,
500 pending_req->pages, pending_req->grant_handles,
501 nr_segments, GNTMAP_host_map | GNTMAP_readonly);
502 if (err)
503 return err;
504 nr_sgl = nr_segments;
505 nr_segments = 0;
506 for (i = 0; i < nr_sgl; i++) {
507 n_segs = ring_req->seg[i].length /
508 sizeof(struct scsiif_request_segment);
509 if ((unsigned)ring_req->seg[i].offset +
510 (unsigned)ring_req->seg[i].length > PAGE_SIZE ||
511 n_segs * sizeof(struct scsiif_request_segment) !=
512 ring_req->seg[i].length)
513 return -EINVAL;
514 nr_segments += n_segs;
515 }
516 if (nr_segments > SG_ALL) {
517 pr_debug("invalid nr_seg = %d\n", nr_segments);
518 return -EINVAL;
519 }
520 }
521
522 /* free of (sgl) in fast_flush_area() */
523 pending_req->sgl = kmalloc_array(nr_segments,
524 sizeof(struct scatterlist), GFP_KERNEL);
525 if (!pending_req->sgl)
526 return -ENOMEM;
527
528 sg_init_table(pending_req->sgl, nr_segments);
529 pending_req->n_sg = nr_segments;
530
531 flags = GNTMAP_host_map;
532 if (pending_req->sc_data_direction == DMA_TO_DEVICE)
533 flags |= GNTMAP_readonly;
534
535 pg = pending_req->pages + nr_sgl;
536 grant = pending_req->grant_handles + nr_sgl;
537 if (!nr_sgl) {
538 seg = ring_req->seg;
539 err = scsiback_gnttab_data_map_list(pending_req, seg,
540 pg, grant, nr_segments, flags);
541 if (err)
542 return err;
543 } else {
544 for (i = 0; i < nr_sgl; i++) {
545 seg = (struct scsiif_request_segment *)(
546 vaddr(pending_req, i) + ring_req->seg[i].offset);
547 n_segs = ring_req->seg[i].length /
548 sizeof(struct scsiif_request_segment);
549 err = scsiback_gnttab_data_map_list(pending_req, seg,
550 pg, grant, n_segs, flags);
551 if (err)
552 return err;
553 pg += n_segs;
554 grant += n_segs;
555 }
556 end_seg = vaddr(pending_req, 0) + ring_req->seg[0].offset;
557 seg = (struct scsiif_request_segment *)end_seg;
558 end_seg += ring_req->seg[0].length;
559 pg = pending_req->pages + nr_sgl;
560 }
561
562 for_each_sg(pending_req->sgl, sg, nr_segments, i) {
563 sg_set_page(sg, pg[i], seg->length, seg->offset);
564 pending_req->data_len += seg->length;
565 seg++;
566 if (nr_sgl && (unsigned long)seg >= end_seg) {
567 i_seg++;
568 end_seg = vaddr(pending_req, i_seg) +
569 ring_req->seg[i_seg].offset;
570 seg = (struct scsiif_request_segment *)end_seg;
571 end_seg += ring_req->seg[i_seg].length;
572 }
573 if (sg->offset >= PAGE_SIZE ||
574 sg->length > PAGE_SIZE ||
575 sg->offset + sg->length > PAGE_SIZE)
576 return -EINVAL;
577 }
578
579 return 0;
580 }
581
582 static void scsiback_disconnect(struct vscsibk_info *info)
583 {
584 wait_event(info->waiting_to_free,
585 atomic_read(&info->nr_unreplied_reqs) == 0);
586
587 unbind_from_irqhandler(info->irq, info);
588 info->irq = 0;
589 xenbus_unmap_ring_vfree(info->dev, info->ring.sring);
590 }
591
592 static void scsiback_device_action(struct vscsibk_pend *pending_req,
593 enum tcm_tmreq_table act, int tag)
594 {
595 int rc, err = FAILED;
596 struct scsiback_tpg *tpg = pending_req->v2p->tpg;
597 struct se_cmd *se_cmd = &pending_req->se_cmd;
598 struct scsiback_tmr *tmr;
599
600 tmr = kzalloc(sizeof(struct scsiback_tmr), GFP_KERNEL);
601 if (!tmr)
602 goto out;
603
604 init_waitqueue_head(&tmr->tmr_wait);
605
606 transport_init_se_cmd(se_cmd, tpg->se_tpg.se_tpg_tfo,
607 tpg->tpg_nexus->tvn_se_sess, 0, DMA_NONE, TCM_SIMPLE_TAG,
608 &pending_req->sense_buffer[0]);
609
610 rc = core_tmr_alloc_req(se_cmd, tmr, act, GFP_KERNEL);
611 if (rc < 0)
612 goto out;
613
614 se_cmd->se_tmr_req->ref_task_tag = tag;
615
616 if (transport_lookup_tmr_lun(se_cmd, pending_req->v2p->lun) < 0)
617 goto out;
618
619 transport_generic_handle_tmr(se_cmd);
620 wait_event(tmr->tmr_wait, atomic_read(&tmr->tmr_complete));
621
622 err = (se_cmd->se_tmr_req->response == TMR_FUNCTION_COMPLETE) ?
623 SUCCESS : FAILED;
624
625 out:
626 if (tmr) {
627 transport_generic_free_cmd(&pending_req->se_cmd, 1);
628 kfree(tmr);
629 }
630
631 scsiback_do_resp_with_sense(NULL, err, 0, pending_req);
632
633 kmem_cache_free(scsiback_cachep, pending_req);
634 }
635
636 /*
637 Perform virtual to physical translation
638 */
639 static struct v2p_entry *scsiback_do_translation(struct vscsibk_info *info,
640 struct ids_tuple *v)
641 {
642 struct v2p_entry *entry;
643 struct list_head *head = &(info->v2p_entry_lists);
644 unsigned long flags;
645
646 spin_lock_irqsave(&info->v2p_lock, flags);
647 list_for_each_entry(entry, head, l) {
648 if ((entry->v.chn == v->chn) &&
649 (entry->v.tgt == v->tgt) &&
650 (entry->v.lun == v->lun)) {
651 kref_get(&entry->kref);
652 goto out;
653 }
654 }
655 entry = NULL;
656
657 out:
658 spin_unlock_irqrestore(&info->v2p_lock, flags);
659 return entry;
660 }
661
662 static int prepare_pending_reqs(struct vscsibk_info *info,
663 struct vscsiif_request *ring_req,
664 struct vscsibk_pend *pending_req)
665 {
666 struct v2p_entry *v2p;
667 struct ids_tuple vir;
668
669 pending_req->rqid = ring_req->rqid;
670 pending_req->info = info;
671
672 vir.chn = ring_req->channel;
673 vir.tgt = ring_req->id;
674 vir.lun = ring_req->lun;
675
676 v2p = scsiback_do_translation(info, &vir);
677 if (!v2p) {
678 pending_req->v2p = NULL;
679 pr_debug("the v2p of (chn:%d, tgt:%d, lun:%d) doesn't exist.\n",
680 vir.chn, vir.tgt, vir.lun);
681 return -ENODEV;
682 }
683 pending_req->v2p = v2p;
684
685 /* request range check from frontend */
686 pending_req->sc_data_direction = ring_req->sc_data_direction;
687 if ((pending_req->sc_data_direction != DMA_BIDIRECTIONAL) &&
688 (pending_req->sc_data_direction != DMA_TO_DEVICE) &&
689 (pending_req->sc_data_direction != DMA_FROM_DEVICE) &&
690 (pending_req->sc_data_direction != DMA_NONE)) {
691 pr_debug("invalid parameter data_dir = %d\n",
692 pending_req->sc_data_direction);
693 return -EINVAL;
694 }
695
696 pending_req->cmd_len = ring_req->cmd_len;
697 if (pending_req->cmd_len > VSCSIIF_MAX_COMMAND_SIZE) {
698 pr_debug("invalid parameter cmd_len = %d\n",
699 pending_req->cmd_len);
700 return -EINVAL;
701 }
702 memcpy(pending_req->cmnd, ring_req->cmnd, pending_req->cmd_len);
703
704 return 0;
705 }
706
707 static int scsiback_do_cmd_fn(struct vscsibk_info *info)
708 {
709 struct vscsiif_back_ring *ring = &info->ring;
710 struct vscsiif_request ring_req;
711 struct vscsibk_pend *pending_req;
712 RING_IDX rc, rp;
713 int err, more_to_do;
714 uint32_t result;
715
716 rc = ring->req_cons;
717 rp = ring->sring->req_prod;
718 rmb(); /* guest system is accessing ring, too */
719
720 if (RING_REQUEST_PROD_OVERFLOW(ring, rp)) {
721 rc = ring->rsp_prod_pvt;
722 pr_warn("Dom%d provided bogus ring requests (%#x - %#x = %u). Halting ring processing\n",
723 info->domid, rp, rc, rp - rc);
724 info->ring_error = 1;
725 return 0;
726 }
727
728 while ((rc != rp)) {
729 if (RING_REQUEST_CONS_OVERFLOW(ring, rc))
730 break;
731 pending_req = kmem_cache_alloc(scsiback_cachep, GFP_KERNEL);
732 if (!pending_req)
733 return 1;
734
735 ring_req = *RING_GET_REQUEST(ring, rc);
736 ring->req_cons = ++rc;
737
738 err = prepare_pending_reqs(info, &ring_req, pending_req);
739 if (err) {
740 switch (err) {
741 case -ENODEV:
742 result = DID_NO_CONNECT;
743 break;
744 default:
745 result = DRIVER_ERROR;
746 break;
747 }
748 scsiback_do_resp_with_sense(NULL, result << 24, 0,
749 pending_req);
750 kmem_cache_free(scsiback_cachep, pending_req);
751 return 1;
752 }
753
754 switch (ring_req.act) {
755 case VSCSIIF_ACT_SCSI_CDB:
756 if (scsiback_gnttab_data_map(&ring_req, pending_req)) {
757 scsiback_fast_flush_area(pending_req);
758 scsiback_do_resp_with_sense(NULL,
759 DRIVER_ERROR << 24, 0, pending_req);
760 kmem_cache_free(scsiback_cachep, pending_req);
761 } else {
762 scsiback_cmd_exec(pending_req);
763 }
764 break;
765 case VSCSIIF_ACT_SCSI_ABORT:
766 scsiback_device_action(pending_req, TMR_ABORT_TASK,
767 ring_req.ref_rqid);
768 break;
769 case VSCSIIF_ACT_SCSI_RESET:
770 scsiback_device_action(pending_req, TMR_LUN_RESET, 0);
771 break;
772 default:
773 pr_err_ratelimited("invalid request\n");
774 scsiback_do_resp_with_sense(NULL, DRIVER_ERROR << 24,
775 0, pending_req);
776 kmem_cache_free(scsiback_cachep, pending_req);
777 break;
778 }
779
780 /* Yield point for this unbounded loop. */
781 cond_resched();
782 }
783
784 RING_FINAL_CHECK_FOR_REQUESTS(&info->ring, more_to_do);
785 return more_to_do;
786 }
787
788 static irqreturn_t scsiback_irq_fn(int irq, void *dev_id)
789 {
790 struct vscsibk_info *info = dev_id;
791
792 if (info->ring_error)
793 return IRQ_HANDLED;
794
795 while (scsiback_do_cmd_fn(info))
796 cond_resched();
797
798 return IRQ_HANDLED;
799 }
800
801 static int scsiback_init_sring(struct vscsibk_info *info, grant_ref_t ring_ref,
802 evtchn_port_t evtchn)
803 {
804 void *area;
805 struct vscsiif_sring *sring;
806 int err;
807
808 if (info->irq)
809 return -1;
810
811 err = xenbus_map_ring_valloc(info->dev, &ring_ref, 1, &area);
812 if (err)
813 return err;
814
815 sring = (struct vscsiif_sring *)area;
816 BACK_RING_INIT(&info->ring, sring, PAGE_SIZE);
817
818 err = bind_interdomain_evtchn_to_irq(info->domid, evtchn);
819 if (err < 0)
820 goto unmap_page;
821
822 info->irq = err;
823
824 err = request_threaded_irq(info->irq, NULL, scsiback_irq_fn,
825 IRQF_ONESHOT, "vscsiif-backend", info);
826 if (err)
827 goto free_irq;
828
829 return 0;
830
831 free_irq:
832 unbind_from_irqhandler(info->irq, info);
833 info->irq = 0;
834 unmap_page:
835 xenbus_unmap_ring_vfree(info->dev, area);
836
837 return err;
838 }
839
840 static int scsiback_map(struct vscsibk_info *info)
841 {
842 struct xenbus_device *dev = info->dev;
843 unsigned int ring_ref, evtchn;
844 int err;
845
846 err = xenbus_gather(XBT_NIL, dev->otherend,
847 "ring-ref", "%u", &ring_ref,
848 "event-channel", "%u", &evtchn, NULL);
849 if (err) {
850 xenbus_dev_fatal(dev, err, "reading %s ring", dev->otherend);
851 return err;
852 }
853
854 return scsiback_init_sring(info, ring_ref, evtchn);
855 }
856
857 /*
858 Add a new translation entry
859 */
860 static int scsiback_add_translation_entry(struct vscsibk_info *info,
861 char *phy, struct ids_tuple *v)
862 {
863 int err = 0;
864 struct v2p_entry *entry;
865 struct v2p_entry *new;
866 struct list_head *head = &(info->v2p_entry_lists);
867 unsigned long flags;
868 char *lunp;
869 unsigned int lun;
870 struct scsiback_tpg *tpg_entry, *tpg = NULL;
871 char *error = "doesn't exist";
872
873 lunp = strrchr(phy, ':');
874 if (!lunp) {
875 pr_err("illegal format of physical device %s\n", phy);
876 return -EINVAL;
877 }
878 *lunp = 0;
879 lunp++;
880 if (kstrtouint(lunp, 10, &lun) || lun >= TRANSPORT_MAX_LUNS_PER_TPG) {
881 pr_err("lun number not valid: %s\n", lunp);
882 return -EINVAL;
883 }
884
885 mutex_lock(&scsiback_mutex);
886 list_for_each_entry(tpg_entry, &scsiback_list, tv_tpg_list) {
887 if (!strcmp(phy, tpg_entry->tport->tport_name) ||
888 !strcmp(phy, tpg_entry->param_alias)) {
889 spin_lock(&tpg_entry->se_tpg.tpg_lun_lock);
890 if (tpg_entry->se_tpg.tpg_lun_list[lun]->lun_status ==
891 TRANSPORT_LUN_STATUS_ACTIVE) {
892 if (!tpg_entry->tpg_nexus)
893 error = "nexus undefined";
894 else
895 tpg = tpg_entry;
896 }
897 spin_unlock(&tpg_entry->se_tpg.tpg_lun_lock);
898 break;
899 }
900 }
901 if (tpg) {
902 mutex_lock(&tpg->tv_tpg_mutex);
903 tpg->tv_tpg_fe_count++;
904 mutex_unlock(&tpg->tv_tpg_mutex);
905 }
906 mutex_unlock(&scsiback_mutex);
907
908 if (!tpg) {
909 pr_err("%s:%d %s\n", phy, lun, error);
910 return -ENODEV;
911 }
912
913 new = kmalloc(sizeof(struct v2p_entry), GFP_KERNEL);
914 if (new == NULL) {
915 err = -ENOMEM;
916 goto out_free;
917 }
918
919 spin_lock_irqsave(&info->v2p_lock, flags);
920
921 /* Check double assignment to identical virtual ID */
922 list_for_each_entry(entry, head, l) {
923 if ((entry->v.chn == v->chn) &&
924 (entry->v.tgt == v->tgt) &&
925 (entry->v.lun == v->lun)) {
926 pr_warn("Virtual ID is already used. Assignment was not performed.\n");
927 err = -EEXIST;
928 goto out;
929 }
930
931 }
932
933 /* Create a new translation entry and add to the list */
934 kref_init(&new->kref);
935 new->v = *v;
936 new->tpg = tpg;
937 new->lun = lun;
938 list_add_tail(&new->l, head);
939
940 out:
941 spin_unlock_irqrestore(&info->v2p_lock, flags);
942
943 out_free:
944 mutex_lock(&tpg->tv_tpg_mutex);
945 tpg->tv_tpg_fe_count--;
946 mutex_unlock(&tpg->tv_tpg_mutex);
947
948 if (err)
949 kfree(new);
950
951 return err;
952 }
953
954 static void __scsiback_del_translation_entry(struct v2p_entry *entry)
955 {
956 list_del(&entry->l);
957 kref_put(&entry->kref, scsiback_free_translation_entry);
958 }
959
960 /*
961 Delete the translation entry specfied
962 */
963 static int scsiback_del_translation_entry(struct vscsibk_info *info,
964 struct ids_tuple *v)
965 {
966 struct v2p_entry *entry;
967 struct list_head *head = &(info->v2p_entry_lists);
968 unsigned long flags;
969
970 spin_lock_irqsave(&info->v2p_lock, flags);
971 /* Find out the translation entry specified */
972 list_for_each_entry(entry, head, l) {
973 if ((entry->v.chn == v->chn) &&
974 (entry->v.tgt == v->tgt) &&
975 (entry->v.lun == v->lun)) {
976 goto found;
977 }
978 }
979
980 spin_unlock_irqrestore(&info->v2p_lock, flags);
981 return 1;
982
983 found:
984 /* Delete the translation entry specfied */
985 __scsiback_del_translation_entry(entry);
986
987 spin_unlock_irqrestore(&info->v2p_lock, flags);
988 return 0;
989 }
990
991 static void scsiback_do_add_lun(struct vscsibk_info *info, const char *state,
992 char *phy, struct ids_tuple *vir, int try)
993 {
994 if (!scsiback_add_translation_entry(info, phy, vir)) {
995 if (xenbus_printf(XBT_NIL, info->dev->nodename, state,
996 "%d", XenbusStateInitialised)) {
997 pr_err("xenbus_printf error %s\n", state);
998 scsiback_del_translation_entry(info, vir);
999 }
1000 } else if (!try) {
1001 xenbus_printf(XBT_NIL, info->dev->nodename, state,
1002 "%d", XenbusStateClosed);
1003 }
1004 }
1005
1006 static void scsiback_do_del_lun(struct vscsibk_info *info, const char *state,
1007 struct ids_tuple *vir)
1008 {
1009 if (!scsiback_del_translation_entry(info, vir)) {
1010 if (xenbus_printf(XBT_NIL, info->dev->nodename, state,
1011 "%d", XenbusStateClosed))
1012 pr_err("xenbus_printf error %s\n", state);
1013 }
1014 }
1015
1016 #define VSCSIBACK_OP_ADD_OR_DEL_LUN 1
1017 #define VSCSIBACK_OP_UPDATEDEV_STATE 2
1018
1019 static void scsiback_do_1lun_hotplug(struct vscsibk_info *info, int op,
1020 char *ent)
1021 {
1022 int err;
1023 struct ids_tuple vir;
1024 char *val;
1025 int device_state;
1026 char phy[VSCSI_NAMELEN];
1027 char str[64];
1028 char state[64];
1029 struct xenbus_device *dev = info->dev;
1030
1031 /* read status */
1032 snprintf(state, sizeof(state), "vscsi-devs/%s/state", ent);
1033 err = xenbus_scanf(XBT_NIL, dev->nodename, state, "%u", &device_state);
1034 if (XENBUS_EXIST_ERR(err))
1035 return;
1036
1037 /* physical SCSI device */
1038 snprintf(str, sizeof(str), "vscsi-devs/%s/p-dev", ent);
1039 val = xenbus_read(XBT_NIL, dev->nodename, str, NULL);
1040 if (IS_ERR(val)) {
1041 xenbus_printf(XBT_NIL, dev->nodename, state,
1042 "%d", XenbusStateClosed);
1043 return;
1044 }
1045 strlcpy(phy, val, VSCSI_NAMELEN);
1046 kfree(val);
1047
1048 /* virtual SCSI device */
1049 snprintf(str, sizeof(str), "vscsi-devs/%s/v-dev", ent);
1050 err = xenbus_scanf(XBT_NIL, dev->nodename, str, "%u:%u:%u:%u",
1051 &vir.hst, &vir.chn, &vir.tgt, &vir.lun);
1052 if (XENBUS_EXIST_ERR(err)) {
1053 xenbus_printf(XBT_NIL, dev->nodename, state,
1054 "%d", XenbusStateClosed);
1055 return;
1056 }
1057
1058 switch (op) {
1059 case VSCSIBACK_OP_ADD_OR_DEL_LUN:
1060 switch (device_state) {
1061 case XenbusStateInitialising:
1062 scsiback_do_add_lun(info, state, phy, &vir, 0);
1063 break;
1064 case XenbusStateConnected:
1065 scsiback_do_add_lun(info, state, phy, &vir, 1);
1066 break;
1067 case XenbusStateClosing:
1068 scsiback_do_del_lun(info, state, &vir);
1069 break;
1070 default:
1071 break;
1072 }
1073 break;
1074
1075 case VSCSIBACK_OP_UPDATEDEV_STATE:
1076 if (device_state == XenbusStateInitialised) {
1077 /* modify vscsi-devs/dev-x/state */
1078 if (xenbus_printf(XBT_NIL, dev->nodename, state,
1079 "%d", XenbusStateConnected)) {
1080 pr_err("xenbus_printf error %s\n", str);
1081 scsiback_del_translation_entry(info, &vir);
1082 xenbus_printf(XBT_NIL, dev->nodename, state,
1083 "%d", XenbusStateClosed);
1084 }
1085 }
1086 break;
1087 /* When it is necessary, processing is added here. */
1088 default:
1089 break;
1090 }
1091 }
1092
1093 static void scsiback_do_lun_hotplug(struct vscsibk_info *info, int op)
1094 {
1095 int i;
1096 char **dir;
1097 unsigned int ndir = 0;
1098
1099 dir = xenbus_directory(XBT_NIL, info->dev->nodename, "vscsi-devs",
1100 &ndir);
1101 if (IS_ERR(dir))
1102 return;
1103
1104 for (i = 0; i < ndir; i++)
1105 scsiback_do_1lun_hotplug(info, op, dir[i]);
1106
1107 kfree(dir);
1108 }
1109
1110 static void scsiback_frontend_changed(struct xenbus_device *dev,
1111 enum xenbus_state frontend_state)
1112 {
1113 struct vscsibk_info *info = dev_get_drvdata(&dev->dev);
1114
1115 switch (frontend_state) {
1116 case XenbusStateInitialising:
1117 break;
1118
1119 case XenbusStateInitialised:
1120 if (scsiback_map(info))
1121 break;
1122
1123 scsiback_do_lun_hotplug(info, VSCSIBACK_OP_ADD_OR_DEL_LUN);
1124 xenbus_switch_state(dev, XenbusStateConnected);
1125 break;
1126
1127 case XenbusStateConnected:
1128 scsiback_do_lun_hotplug(info, VSCSIBACK_OP_UPDATEDEV_STATE);
1129
1130 if (dev->state == XenbusStateConnected)
1131 break;
1132
1133 xenbus_switch_state(dev, XenbusStateConnected);
1134 break;
1135
1136 case XenbusStateClosing:
1137 if (info->irq)
1138 scsiback_disconnect(info);
1139
1140 xenbus_switch_state(dev, XenbusStateClosing);
1141 break;
1142
1143 case XenbusStateClosed:
1144 xenbus_switch_state(dev, XenbusStateClosed);
1145 if (xenbus_dev_is_online(dev))
1146 break;
1147 /* fall through if not online */
1148 case XenbusStateUnknown:
1149 device_unregister(&dev->dev);
1150 break;
1151
1152 case XenbusStateReconfiguring:
1153 scsiback_do_lun_hotplug(info, VSCSIBACK_OP_ADD_OR_DEL_LUN);
1154 xenbus_switch_state(dev, XenbusStateReconfigured);
1155
1156 break;
1157
1158 default:
1159 xenbus_dev_fatal(dev, -EINVAL, "saw state %d at frontend",
1160 frontend_state);
1161 break;
1162 }
1163 }
1164
1165 /*
1166 Release the translation entry specfied
1167 */
1168 static void scsiback_release_translation_entry(struct vscsibk_info *info)
1169 {
1170 struct v2p_entry *entry, *tmp;
1171 struct list_head *head = &(info->v2p_entry_lists);
1172 unsigned long flags;
1173
1174 spin_lock_irqsave(&info->v2p_lock, flags);
1175
1176 list_for_each_entry_safe(entry, tmp, head, l)
1177 __scsiback_del_translation_entry(entry);
1178
1179 spin_unlock_irqrestore(&info->v2p_lock, flags);
1180 }
1181
1182 static int scsiback_remove(struct xenbus_device *dev)
1183 {
1184 struct vscsibk_info *info = dev_get_drvdata(&dev->dev);
1185
1186 if (info->irq)
1187 scsiback_disconnect(info);
1188
1189 scsiback_release_translation_entry(info);
1190
1191 dev_set_drvdata(&dev->dev, NULL);
1192
1193 return 0;
1194 }
1195
1196 static int scsiback_probe(struct xenbus_device *dev,
1197 const struct xenbus_device_id *id)
1198 {
1199 int err;
1200
1201 struct vscsibk_info *info = kzalloc(sizeof(struct vscsibk_info),
1202 GFP_KERNEL);
1203
1204 pr_debug("%s %p %d\n", __func__, dev, dev->otherend_id);
1205
1206 if (!info) {
1207 xenbus_dev_fatal(dev, -ENOMEM, "allocating backend structure");
1208 return -ENOMEM;
1209 }
1210 info->dev = dev;
1211 dev_set_drvdata(&dev->dev, info);
1212
1213 info->domid = dev->otherend_id;
1214 spin_lock_init(&info->ring_lock);
1215 info->ring_error = 0;
1216 atomic_set(&info->nr_unreplied_reqs, 0);
1217 init_waitqueue_head(&info->waiting_to_free);
1218 info->dev = dev;
1219 info->irq = 0;
1220 INIT_LIST_HEAD(&info->v2p_entry_lists);
1221 spin_lock_init(&info->v2p_lock);
1222
1223 err = xenbus_printf(XBT_NIL, dev->nodename, "feature-sg-grant", "%u",
1224 SG_ALL);
1225 if (err)
1226 xenbus_dev_error(dev, err, "writing feature-sg-grant");
1227
1228 err = xenbus_switch_state(dev, XenbusStateInitWait);
1229 if (err)
1230 goto fail;
1231
1232 return 0;
1233
1234 fail:
1235 pr_warn("%s failed\n", __func__);
1236 scsiback_remove(dev);
1237
1238 return err;
1239 }
1240
1241 static char *scsiback_dump_proto_id(struct scsiback_tport *tport)
1242 {
1243 switch (tport->tport_proto_id) {
1244 case SCSI_PROTOCOL_SAS:
1245 return "SAS";
1246 case SCSI_PROTOCOL_FCP:
1247 return "FCP";
1248 case SCSI_PROTOCOL_ISCSI:
1249 return "iSCSI";
1250 default:
1251 break;
1252 }
1253
1254 return "Unknown";
1255 }
1256
1257 static u8 scsiback_get_fabric_proto_ident(struct se_portal_group *se_tpg)
1258 {
1259 struct scsiback_tpg *tpg = container_of(se_tpg,
1260 struct scsiback_tpg, se_tpg);
1261 struct scsiback_tport *tport = tpg->tport;
1262
1263 switch (tport->tport_proto_id) {
1264 case SCSI_PROTOCOL_SAS:
1265 return sas_get_fabric_proto_ident(se_tpg);
1266 case SCSI_PROTOCOL_FCP:
1267 return fc_get_fabric_proto_ident(se_tpg);
1268 case SCSI_PROTOCOL_ISCSI:
1269 return iscsi_get_fabric_proto_ident(se_tpg);
1270 default:
1271 pr_err("Unknown tport_proto_id: 0x%02x, using SAS emulation\n",
1272 tport->tport_proto_id);
1273 break;
1274 }
1275
1276 return sas_get_fabric_proto_ident(se_tpg);
1277 }
1278
1279 static char *scsiback_get_fabric_wwn(struct se_portal_group *se_tpg)
1280 {
1281 struct scsiback_tpg *tpg = container_of(se_tpg,
1282 struct scsiback_tpg, se_tpg);
1283 struct scsiback_tport *tport = tpg->tport;
1284
1285 return &tport->tport_name[0];
1286 }
1287
1288 static u16 scsiback_get_tag(struct se_portal_group *se_tpg)
1289 {
1290 struct scsiback_tpg *tpg = container_of(se_tpg,
1291 struct scsiback_tpg, se_tpg);
1292 return tpg->tport_tpgt;
1293 }
1294
1295 static u32 scsiback_get_default_depth(struct se_portal_group *se_tpg)
1296 {
1297 return 1;
1298 }
1299
1300 static u32
1301 scsiback_get_pr_transport_id(struct se_portal_group *se_tpg,
1302 struct se_node_acl *se_nacl,
1303 struct t10_pr_registration *pr_reg,
1304 int *format_code,
1305 unsigned char *buf)
1306 {
1307 struct scsiback_tpg *tpg = container_of(se_tpg,
1308 struct scsiback_tpg, se_tpg);
1309 struct scsiback_tport *tport = tpg->tport;
1310
1311 switch (tport->tport_proto_id) {
1312 case SCSI_PROTOCOL_SAS:
1313 return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
1314 format_code, buf);
1315 case SCSI_PROTOCOL_FCP:
1316 return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
1317 format_code, buf);
1318 case SCSI_PROTOCOL_ISCSI:
1319 return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
1320 format_code, buf);
1321 default:
1322 pr_err("Unknown tport_proto_id: 0x%02x, using SAS emulation\n",
1323 tport->tport_proto_id);
1324 break;
1325 }
1326
1327 return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
1328 format_code, buf);
1329 }
1330
1331 static u32
1332 scsiback_get_pr_transport_id_len(struct se_portal_group *se_tpg,
1333 struct se_node_acl *se_nacl,
1334 struct t10_pr_registration *pr_reg,
1335 int *format_code)
1336 {
1337 struct scsiback_tpg *tpg = container_of(se_tpg,
1338 struct scsiback_tpg, se_tpg);
1339 struct scsiback_tport *tport = tpg->tport;
1340
1341 switch (tport->tport_proto_id) {
1342 case SCSI_PROTOCOL_SAS:
1343 return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
1344 format_code);
1345 case SCSI_PROTOCOL_FCP:
1346 return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
1347 format_code);
1348 case SCSI_PROTOCOL_ISCSI:
1349 return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
1350 format_code);
1351 default:
1352 pr_err("Unknown tport_proto_id: 0x%02x, using SAS emulation\n",
1353 tport->tport_proto_id);
1354 break;
1355 }
1356
1357 return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
1358 format_code);
1359 }
1360
1361 static char *
1362 scsiback_parse_pr_out_transport_id(struct se_portal_group *se_tpg,
1363 const char *buf,
1364 u32 *out_tid_len,
1365 char **port_nexus_ptr)
1366 {
1367 struct scsiback_tpg *tpg = container_of(se_tpg,
1368 struct scsiback_tpg, se_tpg);
1369 struct scsiback_tport *tport = tpg->tport;
1370
1371 switch (tport->tport_proto_id) {
1372 case SCSI_PROTOCOL_SAS:
1373 return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
1374 port_nexus_ptr);
1375 case SCSI_PROTOCOL_FCP:
1376 return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
1377 port_nexus_ptr);
1378 case SCSI_PROTOCOL_ISCSI:
1379 return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
1380 port_nexus_ptr);
1381 default:
1382 pr_err("Unknown tport_proto_id: 0x%02x, using SAS emulation\n",
1383 tport->tport_proto_id);
1384 break;
1385 }
1386
1387 return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
1388 port_nexus_ptr);
1389 }
1390
1391 static struct se_wwn *
1392 scsiback_make_tport(struct target_fabric_configfs *tf,
1393 struct config_group *group,
1394 const char *name)
1395 {
1396 struct scsiback_tport *tport;
1397 char *ptr;
1398 u64 wwpn = 0;
1399 int off = 0;
1400
1401 tport = kzalloc(sizeof(struct scsiback_tport), GFP_KERNEL);
1402 if (!tport)
1403 return ERR_PTR(-ENOMEM);
1404
1405 tport->tport_wwpn = wwpn;
1406 /*
1407 * Determine the emulated Protocol Identifier and Target Port Name
1408 * based on the incoming configfs directory name.
1409 */
1410 ptr = strstr(name, "naa.");
1411 if (ptr) {
1412 tport->tport_proto_id = SCSI_PROTOCOL_SAS;
1413 goto check_len;
1414 }
1415 ptr = strstr(name, "fc.");
1416 if (ptr) {
1417 tport->tport_proto_id = SCSI_PROTOCOL_FCP;
1418 off = 3; /* Skip over "fc." */
1419 goto check_len;
1420 }
1421 ptr = strstr(name, "iqn.");
1422 if (ptr) {
1423 tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
1424 goto check_len;
1425 }
1426
1427 pr_err("Unable to locate prefix for emulated Target Port: %s\n", name);
1428 kfree(tport);
1429 return ERR_PTR(-EINVAL);
1430
1431 check_len:
1432 if (strlen(name) >= VSCSI_NAMELEN) {
1433 pr_err("Emulated %s Address: %s, exceeds max: %d\n", name,
1434 scsiback_dump_proto_id(tport), VSCSI_NAMELEN);
1435 kfree(tport);
1436 return ERR_PTR(-EINVAL);
1437 }
1438 snprintf(&tport->tport_name[0], VSCSI_NAMELEN, "%s", &name[off]);
1439
1440 pr_debug("Allocated emulated Target %s Address: %s\n",
1441 scsiback_dump_proto_id(tport), name);
1442
1443 return &tport->tport_wwn;
1444 }
1445
1446 static void scsiback_drop_tport(struct se_wwn *wwn)
1447 {
1448 struct scsiback_tport *tport = container_of(wwn,
1449 struct scsiback_tport, tport_wwn);
1450
1451 pr_debug("Deallocating emulated Target %s Address: %s\n",
1452 scsiback_dump_proto_id(tport), tport->tport_name);
1453
1454 kfree(tport);
1455 }
1456
1457 static struct se_node_acl *
1458 scsiback_alloc_fabric_acl(struct se_portal_group *se_tpg)
1459 {
1460 return kzalloc(sizeof(struct se_node_acl), GFP_KERNEL);
1461 }
1462
1463 static void
1464 scsiback_release_fabric_acl(struct se_portal_group *se_tpg,
1465 struct se_node_acl *se_nacl)
1466 {
1467 kfree(se_nacl);
1468 }
1469
1470 static u32 scsiback_tpg_get_inst_index(struct se_portal_group *se_tpg)
1471 {
1472 return 1;
1473 }
1474
1475 static int scsiback_check_stop_free(struct se_cmd *se_cmd)
1476 {
1477 /*
1478 * Do not release struct se_cmd's containing a valid TMR pointer.
1479 * These will be released directly in scsiback_device_action()
1480 * with transport_generic_free_cmd().
1481 */
1482 if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
1483 return 0;
1484
1485 transport_generic_free_cmd(se_cmd, 0);
1486 return 1;
1487 }
1488
1489 static void scsiback_release_cmd(struct se_cmd *se_cmd)
1490 {
1491 struct vscsibk_pend *pending_req = container_of(se_cmd,
1492 struct vscsibk_pend, se_cmd);
1493
1494 kmem_cache_free(scsiback_cachep, pending_req);
1495 }
1496
1497 static int scsiback_shutdown_session(struct se_session *se_sess)
1498 {
1499 return 0;
1500 }
1501
1502 static void scsiback_close_session(struct se_session *se_sess)
1503 {
1504 }
1505
1506 static u32 scsiback_sess_get_index(struct se_session *se_sess)
1507 {
1508 return 0;
1509 }
1510
1511 static int scsiback_write_pending(struct se_cmd *se_cmd)
1512 {
1513 /* Go ahead and process the write immediately */
1514 target_execute_cmd(se_cmd);
1515
1516 return 0;
1517 }
1518
1519 static int scsiback_write_pending_status(struct se_cmd *se_cmd)
1520 {
1521 return 0;
1522 }
1523
1524 static void scsiback_set_default_node_attrs(struct se_node_acl *nacl)
1525 {
1526 }
1527
1528 static u32 scsiback_get_task_tag(struct se_cmd *se_cmd)
1529 {
1530 struct vscsibk_pend *pending_req = container_of(se_cmd,
1531 struct vscsibk_pend, se_cmd);
1532
1533 return pending_req->rqid;
1534 }
1535
1536 static int scsiback_get_cmd_state(struct se_cmd *se_cmd)
1537 {
1538 return 0;
1539 }
1540
1541 static int scsiback_queue_data_in(struct se_cmd *se_cmd)
1542 {
1543 struct vscsibk_pend *pending_req = container_of(se_cmd,
1544 struct vscsibk_pend, se_cmd);
1545
1546 pending_req->result = SAM_STAT_GOOD;
1547 scsiback_cmd_done(pending_req);
1548 return 0;
1549 }
1550
1551 static int scsiback_queue_status(struct se_cmd *se_cmd)
1552 {
1553 struct vscsibk_pend *pending_req = container_of(se_cmd,
1554 struct vscsibk_pend, se_cmd);
1555
1556 if (se_cmd->sense_buffer &&
1557 ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
1558 (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE)))
1559 pending_req->result = (DRIVER_SENSE << 24) |
1560 SAM_STAT_CHECK_CONDITION;
1561 else
1562 pending_req->result = se_cmd->scsi_status;
1563
1564 scsiback_cmd_done(pending_req);
1565 return 0;
1566 }
1567
1568 static void scsiback_queue_tm_rsp(struct se_cmd *se_cmd)
1569 {
1570 struct se_tmr_req *se_tmr = se_cmd->se_tmr_req;
1571 struct scsiback_tmr *tmr = se_tmr->fabric_tmr_ptr;
1572
1573 atomic_set(&tmr->tmr_complete, 1);
1574 wake_up(&tmr->tmr_wait);
1575 }
1576
1577 static void scsiback_aborted_task(struct se_cmd *se_cmd)
1578 {
1579 }
1580
1581 static ssize_t scsiback_tpg_param_show_alias(struct se_portal_group *se_tpg,
1582 char *page)
1583 {
1584 struct scsiback_tpg *tpg = container_of(se_tpg, struct scsiback_tpg,
1585 se_tpg);
1586 ssize_t rb;
1587
1588 mutex_lock(&tpg->tv_tpg_mutex);
1589 rb = snprintf(page, PAGE_SIZE, "%s\n", tpg->param_alias);
1590 mutex_unlock(&tpg->tv_tpg_mutex);
1591
1592 return rb;
1593 }
1594
1595 static ssize_t scsiback_tpg_param_store_alias(struct se_portal_group *se_tpg,
1596 const char *page, size_t count)
1597 {
1598 struct scsiback_tpg *tpg = container_of(se_tpg, struct scsiback_tpg,
1599 se_tpg);
1600 int len;
1601
1602 if (strlen(page) >= VSCSI_NAMELEN) {
1603 pr_err("param alias: %s, exceeds max: %d\n", page,
1604 VSCSI_NAMELEN);
1605 return -EINVAL;
1606 }
1607
1608 mutex_lock(&tpg->tv_tpg_mutex);
1609 len = snprintf(tpg->param_alias, VSCSI_NAMELEN, "%s", page);
1610 if (tpg->param_alias[len - 1] == '\n')
1611 tpg->param_alias[len - 1] = '\0';
1612 mutex_unlock(&tpg->tv_tpg_mutex);
1613
1614 return count;
1615 }
1616
1617 TF_TPG_PARAM_ATTR(scsiback, alias, S_IRUGO | S_IWUSR);
1618
1619 static struct configfs_attribute *scsiback_param_attrs[] = {
1620 &scsiback_tpg_param_alias.attr,
1621 NULL,
1622 };
1623
1624 static int scsiback_make_nexus(struct scsiback_tpg *tpg,
1625 const char *name)
1626 {
1627 struct se_portal_group *se_tpg;
1628 struct se_session *se_sess;
1629 struct scsiback_nexus *tv_nexus;
1630
1631 mutex_lock(&tpg->tv_tpg_mutex);
1632 if (tpg->tpg_nexus) {
1633 mutex_unlock(&tpg->tv_tpg_mutex);
1634 pr_debug("tpg->tpg_nexus already exists\n");
1635 return -EEXIST;
1636 }
1637 se_tpg = &tpg->se_tpg;
1638
1639 tv_nexus = kzalloc(sizeof(struct scsiback_nexus), GFP_KERNEL);
1640 if (!tv_nexus) {
1641 mutex_unlock(&tpg->tv_tpg_mutex);
1642 return -ENOMEM;
1643 }
1644 /*
1645 * Initialize the struct se_session pointer
1646 */
1647 tv_nexus->tvn_se_sess = transport_init_session(TARGET_PROT_NORMAL);
1648 if (IS_ERR(tv_nexus->tvn_se_sess)) {
1649 mutex_unlock(&tpg->tv_tpg_mutex);
1650 kfree(tv_nexus);
1651 return -ENOMEM;
1652 }
1653 se_sess = tv_nexus->tvn_se_sess;
1654 /*
1655 * Since we are running in 'demo mode' this call with generate a
1656 * struct se_node_acl for the scsiback struct se_portal_group with
1657 * the SCSI Initiator port name of the passed configfs group 'name'.
1658 */
1659 tv_nexus->tvn_se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
1660 se_tpg, (unsigned char *)name);
1661 if (!tv_nexus->tvn_se_sess->se_node_acl) {
1662 mutex_unlock(&tpg->tv_tpg_mutex);
1663 pr_debug("core_tpg_check_initiator_node_acl() failed for %s\n",
1664 name);
1665 goto out;
1666 }
1667 /* Now register the TCM pvscsi virtual I_T Nexus as active. */
1668 transport_register_session(se_tpg, tv_nexus->tvn_se_sess->se_node_acl,
1669 tv_nexus->tvn_se_sess, tv_nexus);
1670 tpg->tpg_nexus = tv_nexus;
1671
1672 mutex_unlock(&tpg->tv_tpg_mutex);
1673 return 0;
1674
1675 out:
1676 transport_free_session(se_sess);
1677 kfree(tv_nexus);
1678 return -ENOMEM;
1679 }
1680
1681 static int scsiback_drop_nexus(struct scsiback_tpg *tpg)
1682 {
1683 struct se_session *se_sess;
1684 struct scsiback_nexus *tv_nexus;
1685
1686 mutex_lock(&tpg->tv_tpg_mutex);
1687 tv_nexus = tpg->tpg_nexus;
1688 if (!tv_nexus) {
1689 mutex_unlock(&tpg->tv_tpg_mutex);
1690 return -ENODEV;
1691 }
1692
1693 se_sess = tv_nexus->tvn_se_sess;
1694 if (!se_sess) {
1695 mutex_unlock(&tpg->tv_tpg_mutex);
1696 return -ENODEV;
1697 }
1698
1699 if (tpg->tv_tpg_port_count != 0) {
1700 mutex_unlock(&tpg->tv_tpg_mutex);
1701 pr_err("Unable to remove xen-pvscsi I_T Nexus with active TPG port count: %d\n",
1702 tpg->tv_tpg_port_count);
1703 return -EBUSY;
1704 }
1705
1706 if (tpg->tv_tpg_fe_count != 0) {
1707 mutex_unlock(&tpg->tv_tpg_mutex);
1708 pr_err("Unable to remove xen-pvscsi I_T Nexus with active TPG frontend count: %d\n",
1709 tpg->tv_tpg_fe_count);
1710 return -EBUSY;
1711 }
1712
1713 pr_debug("Removing I_T Nexus to emulated %s Initiator Port: %s\n",
1714 scsiback_dump_proto_id(tpg->tport),
1715 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1716
1717 /*
1718 * Release the SCSI I_T Nexus to the emulated xen-pvscsi Target Port
1719 */
1720 transport_deregister_session(tv_nexus->tvn_se_sess);
1721 tpg->tpg_nexus = NULL;
1722 mutex_unlock(&tpg->tv_tpg_mutex);
1723
1724 kfree(tv_nexus);
1725 return 0;
1726 }
1727
1728 static ssize_t scsiback_tpg_show_nexus(struct se_portal_group *se_tpg,
1729 char *page)
1730 {
1731 struct scsiback_tpg *tpg = container_of(se_tpg,
1732 struct scsiback_tpg, se_tpg);
1733 struct scsiback_nexus *tv_nexus;
1734 ssize_t ret;
1735
1736 mutex_lock(&tpg->tv_tpg_mutex);
1737 tv_nexus = tpg->tpg_nexus;
1738 if (!tv_nexus) {
1739 mutex_unlock(&tpg->tv_tpg_mutex);
1740 return -ENODEV;
1741 }
1742 ret = snprintf(page, PAGE_SIZE, "%s\n",
1743 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1744 mutex_unlock(&tpg->tv_tpg_mutex);
1745
1746 return ret;
1747 }
1748
1749 static ssize_t scsiback_tpg_store_nexus(struct se_portal_group *se_tpg,
1750 const char *page,
1751 size_t count)
1752 {
1753 struct scsiback_tpg *tpg = container_of(se_tpg,
1754 struct scsiback_tpg, se_tpg);
1755 struct scsiback_tport *tport_wwn = tpg->tport;
1756 unsigned char i_port[VSCSI_NAMELEN], *ptr, *port_ptr;
1757 int ret;
1758 /*
1759 * Shutdown the active I_T nexus if 'NULL' is passed.
1760 */
1761 if (!strncmp(page, "NULL", 4)) {
1762 ret = scsiback_drop_nexus(tpg);
1763 return (!ret) ? count : ret;
1764 }
1765 /*
1766 * Otherwise make sure the passed virtual Initiator port WWN matches
1767 * the fabric protocol_id set in scsiback_make_tport(), and call
1768 * scsiback_make_nexus().
1769 */
1770 if (strlen(page) >= VSCSI_NAMELEN) {
1771 pr_err("Emulated NAA Sas Address: %s, exceeds max: %d\n",
1772 page, VSCSI_NAMELEN);
1773 return -EINVAL;
1774 }
1775 snprintf(&i_port[0], VSCSI_NAMELEN, "%s", page);
1776
1777 ptr = strstr(i_port, "naa.");
1778 if (ptr) {
1779 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
1780 pr_err("Passed SAS Initiator Port %s does not match target port protoid: %s\n",
1781 i_port, scsiback_dump_proto_id(tport_wwn));
1782 return -EINVAL;
1783 }
1784 port_ptr = &i_port[0];
1785 goto check_newline;
1786 }
1787 ptr = strstr(i_port, "fc.");
1788 if (ptr) {
1789 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
1790 pr_err("Passed FCP Initiator Port %s does not match target port protoid: %s\n",
1791 i_port, scsiback_dump_proto_id(tport_wwn));
1792 return -EINVAL;
1793 }
1794 port_ptr = &i_port[3]; /* Skip over "fc." */
1795 goto check_newline;
1796 }
1797 ptr = strstr(i_port, "iqn.");
1798 if (ptr) {
1799 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
1800 pr_err("Passed iSCSI Initiator Port %s does not match target port protoid: %s\n",
1801 i_port, scsiback_dump_proto_id(tport_wwn));
1802 return -EINVAL;
1803 }
1804 port_ptr = &i_port[0];
1805 goto check_newline;
1806 }
1807 pr_err("Unable to locate prefix for emulated Initiator Port: %s\n",
1808 i_port);
1809 return -EINVAL;
1810 /*
1811 * Clear any trailing newline for the NAA WWN
1812 */
1813 check_newline:
1814 if (i_port[strlen(i_port) - 1] == '\n')
1815 i_port[strlen(i_port) - 1] = '\0';
1816
1817 ret = scsiback_make_nexus(tpg, port_ptr);
1818 if (ret < 0)
1819 return ret;
1820
1821 return count;
1822 }
1823
1824 TF_TPG_BASE_ATTR(scsiback, nexus, S_IRUGO | S_IWUSR);
1825
1826 static struct configfs_attribute *scsiback_tpg_attrs[] = {
1827 &scsiback_tpg_nexus.attr,
1828 NULL,
1829 };
1830
1831 static ssize_t
1832 scsiback_wwn_show_attr_version(struct target_fabric_configfs *tf,
1833 char *page)
1834 {
1835 return sprintf(page, "xen-pvscsi fabric module %s on %s/%s on "
1836 UTS_RELEASE"\n",
1837 VSCSI_VERSION, utsname()->sysname, utsname()->machine);
1838 }
1839
1840 TF_WWN_ATTR_RO(scsiback, version);
1841
1842 static struct configfs_attribute *scsiback_wwn_attrs[] = {
1843 &scsiback_wwn_version.attr,
1844 NULL,
1845 };
1846
1847 static char *scsiback_get_fabric_name(void)
1848 {
1849 return "xen-pvscsi";
1850 }
1851
1852 static int scsiback_port_link(struct se_portal_group *se_tpg,
1853 struct se_lun *lun)
1854 {
1855 struct scsiback_tpg *tpg = container_of(se_tpg,
1856 struct scsiback_tpg, se_tpg);
1857
1858 mutex_lock(&tpg->tv_tpg_mutex);
1859 tpg->tv_tpg_port_count++;
1860 mutex_unlock(&tpg->tv_tpg_mutex);
1861
1862 return 0;
1863 }
1864
1865 static void scsiback_port_unlink(struct se_portal_group *se_tpg,
1866 struct se_lun *lun)
1867 {
1868 struct scsiback_tpg *tpg = container_of(se_tpg,
1869 struct scsiback_tpg, se_tpg);
1870
1871 mutex_lock(&tpg->tv_tpg_mutex);
1872 tpg->tv_tpg_port_count--;
1873 mutex_unlock(&tpg->tv_tpg_mutex);
1874 }
1875
1876 static struct se_portal_group *
1877 scsiback_make_tpg(struct se_wwn *wwn,
1878 struct config_group *group,
1879 const char *name)
1880 {
1881 struct scsiback_tport *tport = container_of(wwn,
1882 struct scsiback_tport, tport_wwn);
1883
1884 struct scsiback_tpg *tpg;
1885 u16 tpgt;
1886 int ret;
1887
1888 if (strstr(name, "tpgt_") != name)
1889 return ERR_PTR(-EINVAL);
1890 ret = kstrtou16(name + 5, 10, &tpgt);
1891 if (ret)
1892 return ERR_PTR(ret);
1893
1894 tpg = kzalloc(sizeof(struct scsiback_tpg), GFP_KERNEL);
1895 if (!tpg)
1896 return ERR_PTR(-ENOMEM);
1897
1898 mutex_init(&tpg->tv_tpg_mutex);
1899 INIT_LIST_HEAD(&tpg->tv_tpg_list);
1900 INIT_LIST_HEAD(&tpg->info_list);
1901 tpg->tport = tport;
1902 tpg->tport_tpgt = tpgt;
1903
1904 ret = core_tpg_register(&scsiback_ops, wwn,
1905 &tpg->se_tpg, tpg, TRANSPORT_TPG_TYPE_NORMAL);
1906 if (ret < 0) {
1907 kfree(tpg);
1908 return NULL;
1909 }
1910 mutex_lock(&scsiback_mutex);
1911 list_add_tail(&tpg->tv_tpg_list, &scsiback_list);
1912 mutex_unlock(&scsiback_mutex);
1913
1914 return &tpg->se_tpg;
1915 }
1916
1917 static void scsiback_drop_tpg(struct se_portal_group *se_tpg)
1918 {
1919 struct scsiback_tpg *tpg = container_of(se_tpg,
1920 struct scsiback_tpg, se_tpg);
1921
1922 mutex_lock(&scsiback_mutex);
1923 list_del(&tpg->tv_tpg_list);
1924 mutex_unlock(&scsiback_mutex);
1925 /*
1926 * Release the virtual I_T Nexus for this xen-pvscsi TPG
1927 */
1928 scsiback_drop_nexus(tpg);
1929 /*
1930 * Deregister the se_tpg from TCM.
1931 */
1932 core_tpg_deregister(se_tpg);
1933 kfree(tpg);
1934 }
1935
1936 static int scsiback_check_true(struct se_portal_group *se_tpg)
1937 {
1938 return 1;
1939 }
1940
1941 static int scsiback_check_false(struct se_portal_group *se_tpg)
1942 {
1943 return 0;
1944 }
1945
1946 static const struct target_core_fabric_ops scsiback_ops = {
1947 .module = THIS_MODULE,
1948 .name = "xen-pvscsi",
1949 .get_fabric_name = scsiback_get_fabric_name,
1950 .get_fabric_proto_ident = scsiback_get_fabric_proto_ident,
1951 .tpg_get_wwn = scsiback_get_fabric_wwn,
1952 .tpg_get_tag = scsiback_get_tag,
1953 .tpg_get_default_depth = scsiback_get_default_depth,
1954 .tpg_get_pr_transport_id = scsiback_get_pr_transport_id,
1955 .tpg_get_pr_transport_id_len = scsiback_get_pr_transport_id_len,
1956 .tpg_parse_pr_out_transport_id = scsiback_parse_pr_out_transport_id,
1957 .tpg_check_demo_mode = scsiback_check_true,
1958 .tpg_check_demo_mode_cache = scsiback_check_true,
1959 .tpg_check_demo_mode_write_protect = scsiback_check_false,
1960 .tpg_check_prod_mode_write_protect = scsiback_check_false,
1961 .tpg_alloc_fabric_acl = scsiback_alloc_fabric_acl,
1962 .tpg_release_fabric_acl = scsiback_release_fabric_acl,
1963 .tpg_get_inst_index = scsiback_tpg_get_inst_index,
1964 .check_stop_free = scsiback_check_stop_free,
1965 .release_cmd = scsiback_release_cmd,
1966 .put_session = NULL,
1967 .shutdown_session = scsiback_shutdown_session,
1968 .close_session = scsiback_close_session,
1969 .sess_get_index = scsiback_sess_get_index,
1970 .sess_get_initiator_sid = NULL,
1971 .write_pending = scsiback_write_pending,
1972 .write_pending_status = scsiback_write_pending_status,
1973 .set_default_node_attributes = scsiback_set_default_node_attrs,
1974 .get_task_tag = scsiback_get_task_tag,
1975 .get_cmd_state = scsiback_get_cmd_state,
1976 .queue_data_in = scsiback_queue_data_in,
1977 .queue_status = scsiback_queue_status,
1978 .queue_tm_rsp = scsiback_queue_tm_rsp,
1979 .aborted_task = scsiback_aborted_task,
1980 /*
1981 * Setup callers for generic logic in target_core_fabric_configfs.c
1982 */
1983 .fabric_make_wwn = scsiback_make_tport,
1984 .fabric_drop_wwn = scsiback_drop_tport,
1985 .fabric_make_tpg = scsiback_make_tpg,
1986 .fabric_drop_tpg = scsiback_drop_tpg,
1987 .fabric_post_link = scsiback_port_link,
1988 .fabric_pre_unlink = scsiback_port_unlink,
1989 .fabric_make_np = NULL,
1990 .fabric_drop_np = NULL,
1991 #if 0
1992 .fabric_make_nodeacl = scsiback_make_nodeacl,
1993 .fabric_drop_nodeacl = scsiback_drop_nodeacl,
1994 #endif
1995
1996 .tfc_wwn_attrs = scsiback_wwn_attrs,
1997 .tfc_tpg_base_attrs = scsiback_tpg_attrs,
1998 .tfc_tpg_param_attrs = scsiback_param_attrs,
1999 };
2000
2001 static const struct xenbus_device_id scsiback_ids[] = {
2002 { "vscsi" },
2003 { "" }
2004 };
2005
2006 static struct xenbus_driver scsiback_driver = {
2007 .ids = scsiback_ids,
2008 .probe = scsiback_probe,
2009 .remove = scsiback_remove,
2010 .otherend_changed = scsiback_frontend_changed
2011 };
2012
2013 static void scsiback_init_pend(void *p)
2014 {
2015 struct vscsibk_pend *pend = p;
2016 int i;
2017
2018 memset(pend, 0, sizeof(*pend));
2019 for (i = 0; i < VSCSI_MAX_GRANTS; i++)
2020 pend->grant_handles[i] = SCSIBACK_INVALID_HANDLE;
2021 }
2022
2023 static int __init scsiback_init(void)
2024 {
2025 int ret;
2026
2027 if (!xen_domain())
2028 return -ENODEV;
2029
2030 pr_debug("xen-pvscsi: fabric module %s on %s/%s on "UTS_RELEASE"\n",
2031 VSCSI_VERSION, utsname()->sysname, utsname()->machine);
2032
2033 scsiback_cachep = kmem_cache_create("vscsiif_cache",
2034 sizeof(struct vscsibk_pend), 0, 0, scsiback_init_pend);
2035 if (!scsiback_cachep)
2036 return -ENOMEM;
2037
2038 ret = xenbus_register_backend(&scsiback_driver);
2039 if (ret)
2040 goto out_cache_destroy;
2041
2042 ret = target_register_template(&scsiback_ops);
2043 if (ret)
2044 goto out_unregister_xenbus;
2045
2046 return 0;
2047
2048 out_unregister_xenbus:
2049 xenbus_unregister_driver(&scsiback_driver);
2050 out_cache_destroy:
2051 kmem_cache_destroy(scsiback_cachep);
2052 pr_err("%s: error %d\n", __func__, ret);
2053 return ret;
2054 }
2055
2056 static void __exit scsiback_exit(void)
2057 {
2058 struct page *page;
2059
2060 while (free_pages_num) {
2061 if (get_free_page(&page))
2062 BUG();
2063 gnttab_free_pages(1, &page);
2064 }
2065 target_unregister_template(&scsiback_ops);
2066 xenbus_unregister_driver(&scsiback_driver);
2067 kmem_cache_destroy(scsiback_cachep);
2068 }
2069
2070 module_init(scsiback_init);
2071 module_exit(scsiback_exit);
2072
2073 MODULE_DESCRIPTION("Xen SCSI backend driver");
2074 MODULE_LICENSE("Dual BSD/GPL");
2075 MODULE_ALIAS("xen-backend:vscsi");
2076 MODULE_AUTHOR("Juergen Gross <jgross@suse.com>");
Linux with added FPC-III support