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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_host.h>
53
54#include <target/target_core_base.h>
55#include <target/target_core_fabric.h>
56
57#include <asm/hypervisor.h>
58
59#include <xen/xen.h>
60#include <xen/balloon.h>
61#include <xen/events.h>
62#include <xen/xenbus.h>
63#include <xen/grant_table.h>
64#include <xen/page.h>
65
66#include <xen/interface/grant_table.h>
67#include <xen/interface/io/vscsiif.h>
68
69#define VSCSI_VERSION "v0.1"
70#define VSCSI_NAMELEN 32
71
72struct ids_tuple {
73 unsigned int hst;
74 unsigned int chn;
75 unsigned int tgt;
76 unsigned int lun;
77};
78
79struct v2p_entry {
80 struct ids_tuple v;
81 struct scsiback_tpg *tpg;
82 unsigned int lun;
83 struct kref kref;
84 struct list_head l;
85};
86
87struct vscsibk_info {
88 struct xenbus_device *dev;
89
90 domid_t domid;
91 unsigned int irq;
92
93 struct vscsiif_back_ring ring;
94
95 spinlock_t ring_lock;
96 atomic_t nr_unreplied_reqs;
97
98 spinlock_t v2p_lock;
99 struct list_head v2p_entry_lists;
100
101 wait_queue_head_t waiting_to_free;
102
103 struct gnttab_page_cache free_pages;
104};
105
106
107#define VSCSI_MAX_GRANTS (SG_ALL + VSCSIIF_SG_TABLESIZE)
108
109
110
111
112
113
114#define VSCSI_GRANT_BATCH 16
115
116struct vscsibk_pend {
117 uint16_t rqid;
118
119 uint8_t cmnd[VSCSIIF_MAX_COMMAND_SIZE];
120 uint8_t cmd_len;
121
122 uint8_t sc_data_direction;
123 uint16_t n_sg;
124 uint16_t n_grants;
125 uint32_t data_len;
126 uint32_t result;
127
128 struct vscsibk_info *info;
129 struct v2p_entry *v2p;
130 struct scatterlist *sgl;
131
132 uint8_t sense_buffer[VSCSIIF_SENSE_BUFFERSIZE];
133
134 grant_handle_t grant_handles[VSCSI_MAX_GRANTS];
135 struct page *pages[VSCSI_MAX_GRANTS];
136
137 struct se_cmd se_cmd;
138
139 struct completion tmr_done;
140};
141
142#define VSCSI_DEFAULT_SESSION_TAGS 128
143
144struct scsiback_nexus {
145
146 struct se_session *tvn_se_sess;
147};
148
149struct scsiback_tport {
150
151 u8 tport_proto_id;
152
153 u64 tport_wwpn;
154
155 char tport_name[VSCSI_NAMELEN];
156
157 struct se_wwn tport_wwn;
158};
159
160struct scsiback_tpg {
161
162 u16 tport_tpgt;
163
164 int tv_tpg_port_count;
165
166 int tv_tpg_fe_count;
167
168 struct list_head tv_tpg_list;
169
170 struct mutex tv_tpg_mutex;
171
172 struct scsiback_nexus *tpg_nexus;
173
174 struct scsiback_tport *tport;
175
176 struct se_portal_group se_tpg;
177
178 char param_alias[VSCSI_NAMELEN];
179
180 struct list_head info_list;
181};
182
183#define SCSIBACK_INVALID_HANDLE (~0)
184
185static bool log_print_stat;
186module_param(log_print_stat, bool, 0644);
187
188static int scsiback_max_buffer_pages = 1024;
189module_param_named(max_buffer_pages, scsiback_max_buffer_pages, int, 0644);
190MODULE_PARM_DESC(max_buffer_pages,
191"Maximum number of free pages to keep in backend buffer");
192
193
194static DEFINE_MUTEX(scsiback_mutex);
195static LIST_HEAD(scsiback_list);
196
197static void scsiback_get(struct vscsibk_info *info)
198{
199 atomic_inc(&info->nr_unreplied_reqs);
200}
201
202static void scsiback_put(struct vscsibk_info *info)
203{
204 if (atomic_dec_and_test(&info->nr_unreplied_reqs))
205 wake_up(&info->waiting_to_free);
206}
207
208static unsigned long vaddr_page(struct page *page)
209{
210 unsigned long pfn = page_to_pfn(page);
211
212 return (unsigned long)pfn_to_kaddr(pfn);
213}
214
215static unsigned long vaddr(struct vscsibk_pend *req, int seg)
216{
217 return vaddr_page(req->pages[seg]);
218}
219
220static void scsiback_print_status(char *sense_buffer, int errors,
221 struct vscsibk_pend *pending_req)
222{
223 struct scsiback_tpg *tpg = pending_req->v2p->tpg;
224
225 pr_err("[%s:%d] cmnd[0]=%02x -> st=%02x msg=%02x host=%02x\n",
226 tpg->tport->tport_name, pending_req->v2p->lun,
227 pending_req->cmnd[0], errors & 0xff, COMMAND_COMPLETE,
228 host_byte(errors));
229}
230
231static void scsiback_fast_flush_area(struct vscsibk_pend *req)
232{
233 struct gnttab_unmap_grant_ref unmap[VSCSI_GRANT_BATCH];
234 struct page *pages[VSCSI_GRANT_BATCH];
235 unsigned int i, invcount = 0;
236 grant_handle_t handle;
237 int err;
238
239 kfree(req->sgl);
240 req->sgl = NULL;
241 req->n_sg = 0;
242
243 if (!req->n_grants)
244 return;
245
246 for (i = 0; i < req->n_grants; i++) {
247 handle = req->grant_handles[i];
248 if (handle == SCSIBACK_INVALID_HANDLE)
249 continue;
250 gnttab_set_unmap_op(&unmap[invcount], vaddr(req, i),
251 GNTMAP_host_map, handle);
252 req->grant_handles[i] = SCSIBACK_INVALID_HANDLE;
253 pages[invcount] = req->pages[i];
254 put_page(pages[invcount]);
255 invcount++;
256 if (invcount < VSCSI_GRANT_BATCH)
257 continue;
258 err = gnttab_unmap_refs(unmap, NULL, pages, invcount);
259 BUG_ON(err);
260 invcount = 0;
261 }
262
263 if (invcount) {
264 err = gnttab_unmap_refs(unmap, NULL, pages, invcount);
265 BUG_ON(err);
266 }
267
268 gnttab_page_cache_put(&req->info->free_pages, req->pages,
269 req->n_grants);
270 req->n_grants = 0;
271}
272
273static void scsiback_free_translation_entry(struct kref *kref)
274{
275 struct v2p_entry *entry = container_of(kref, struct v2p_entry, kref);
276 struct scsiback_tpg *tpg = entry->tpg;
277
278 mutex_lock(&tpg->tv_tpg_mutex);
279 tpg->tv_tpg_fe_count--;
280 mutex_unlock(&tpg->tv_tpg_mutex);
281
282 kfree(entry);
283}
284
285static void scsiback_send_response(struct vscsibk_info *info,
286 char *sense_buffer, int32_t result, uint32_t resid,
287 uint16_t rqid)
288{
289 struct vscsiif_response *ring_res;
290 int notify;
291 struct scsi_sense_hdr sshdr;
292 unsigned long flags;
293 unsigned len;
294
295 spin_lock_irqsave(&info->ring_lock, flags);
296
297 ring_res = RING_GET_RESPONSE(&info->ring, info->ring.rsp_prod_pvt);
298 info->ring.rsp_prod_pvt++;
299
300 ring_res->rslt = result;
301 ring_res->rqid = rqid;
302
303 if (sense_buffer != NULL &&
304 scsi_normalize_sense(sense_buffer, VSCSIIF_SENSE_BUFFERSIZE,
305 &sshdr)) {
306 len = min_t(unsigned, 8 + sense_buffer[7],
307 VSCSIIF_SENSE_BUFFERSIZE);
308 memcpy(ring_res->sense_buffer, sense_buffer, len);
309 ring_res->sense_len = len;
310 } else {
311 ring_res->sense_len = 0;
312 }
313
314 ring_res->residual_len = resid;
315
316 RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&info->ring, notify);
317 spin_unlock_irqrestore(&info->ring_lock, flags);
318
319 if (notify)
320 notify_remote_via_irq(info->irq);
321}
322
323static void scsiback_do_resp_with_sense(char *sense_buffer, int32_t result,
324 uint32_t resid, struct vscsibk_pend *pending_req)
325{
326 scsiback_send_response(pending_req->info, sense_buffer, result,
327 resid, pending_req->rqid);
328
329 if (pending_req->v2p)
330 kref_put(&pending_req->v2p->kref,
331 scsiback_free_translation_entry);
332}
333
334static void scsiback_cmd_done(struct vscsibk_pend *pending_req)
335{
336 struct vscsibk_info *info = pending_req->info;
337 unsigned char *sense_buffer;
338 unsigned int resid;
339 int errors;
340
341 sense_buffer = pending_req->sense_buffer;
342 resid = pending_req->se_cmd.residual_count;
343 errors = pending_req->result;
344
345 if (errors && log_print_stat)
346 scsiback_print_status(sense_buffer, errors, pending_req);
347
348 scsiback_fast_flush_area(pending_req);
349 scsiback_do_resp_with_sense(sense_buffer, errors, resid, pending_req);
350 scsiback_put(info);
351
352
353
354
355
356 target_put_sess_cmd(&pending_req->se_cmd);
357}
358
359static void scsiback_cmd_exec(struct vscsibk_pend *pending_req)
360{
361 struct se_cmd *se_cmd = &pending_req->se_cmd;
362 struct se_session *sess = pending_req->v2p->tpg->tpg_nexus->tvn_se_sess;
363
364 scsiback_get(pending_req->info);
365 se_cmd->tag = pending_req->rqid;
366 target_init_cmd(se_cmd, sess, pending_req->sense_buffer,
367 pending_req->v2p->lun, pending_req->data_len, 0,
368 pending_req->sc_data_direction, TARGET_SCF_ACK_KREF);
369
370 if (target_submit_prep(se_cmd, pending_req->cmnd, pending_req->sgl,
371 pending_req->n_sg, NULL, 0, NULL, 0, GFP_KERNEL))
372 return;
373
374 target_submit(se_cmd);
375}
376
377static int scsiback_gnttab_data_map_batch(struct gnttab_map_grant_ref *map,
378 struct page **pg, grant_handle_t *grant, int cnt)
379{
380 int err, i;
381
382 if (!cnt)
383 return 0;
384
385 err = gnttab_map_refs(map, NULL, pg, cnt);
386 for (i = 0; i < cnt; i++) {
387 if (unlikely(map[i].status != GNTST_okay)) {
388 pr_err("invalid buffer -- could not remap it\n");
389 map[i].handle = SCSIBACK_INVALID_HANDLE;
390 if (!err)
391 err = -ENOMEM;
392 } else {
393 get_page(pg[i]);
394 }
395 grant[i] = map[i].handle;
396 }
397 return err;
398}
399
400static int scsiback_gnttab_data_map_list(struct vscsibk_pend *pending_req,
401 struct scsiif_request_segment *seg, struct page **pg,
402 grant_handle_t *grant, int cnt, u32 flags)
403{
404 int mapcount = 0, i, err = 0;
405 struct gnttab_map_grant_ref map[VSCSI_GRANT_BATCH];
406 struct vscsibk_info *info = pending_req->info;
407
408 for (i = 0; i < cnt; i++) {
409 if (gnttab_page_cache_get(&info->free_pages, pg + mapcount)) {
410 gnttab_page_cache_put(&info->free_pages, pg, mapcount);
411 pr_err("no grant page\n");
412 return -ENOMEM;
413 }
414 gnttab_set_map_op(&map[mapcount], vaddr_page(pg[mapcount]),
415 flags, seg[i].gref, info->domid);
416 mapcount++;
417 if (mapcount < VSCSI_GRANT_BATCH)
418 continue;
419 err = scsiback_gnttab_data_map_batch(map, pg, grant, mapcount);
420 pg += mapcount;
421 grant += mapcount;
422 pending_req->n_grants += mapcount;
423 if (err)
424 return err;
425 mapcount = 0;
426 }
427 err = scsiback_gnttab_data_map_batch(map, pg, grant, mapcount);
428 pending_req->n_grants += mapcount;
429 return err;
430}
431
432static int scsiback_gnttab_data_map(struct vscsiif_request *ring_req,
433 struct vscsibk_pend *pending_req)
434{
435 u32 flags;
436 int i, err, n_segs, i_seg = 0;
437 struct page **pg;
438 struct scsiif_request_segment *seg;
439 unsigned long end_seg = 0;
440 unsigned int nr_segments = (unsigned int)ring_req->nr_segments;
441 unsigned int nr_sgl = 0;
442 struct scatterlist *sg;
443 grant_handle_t *grant;
444
445 pending_req->n_sg = 0;
446 pending_req->n_grants = 0;
447 pending_req->data_len = 0;
448
449 nr_segments &= ~VSCSIIF_SG_GRANT;
450 if (!nr_segments)
451 return 0;
452
453 if (nr_segments > VSCSIIF_SG_TABLESIZE) {
454 pr_debug("invalid parameter nr_seg = %d\n",
455 ring_req->nr_segments);
456 return -EINVAL;
457 }
458
459 if (ring_req->nr_segments & VSCSIIF_SG_GRANT) {
460 err = scsiback_gnttab_data_map_list(pending_req, ring_req->seg,
461 pending_req->pages, pending_req->grant_handles,
462 nr_segments, GNTMAP_host_map | GNTMAP_readonly);
463 if (err)
464 return err;
465 nr_sgl = nr_segments;
466 nr_segments = 0;
467 for (i = 0; i < nr_sgl; i++) {
468 n_segs = ring_req->seg[i].length /
469 sizeof(struct scsiif_request_segment);
470 if ((unsigned)ring_req->seg[i].offset +
471 (unsigned)ring_req->seg[i].length > PAGE_SIZE ||
472 n_segs * sizeof(struct scsiif_request_segment) !=
473 ring_req->seg[i].length)
474 return -EINVAL;
475 nr_segments += n_segs;
476 }
477 if (nr_segments > SG_ALL) {
478 pr_debug("invalid nr_seg = %d\n", nr_segments);
479 return -EINVAL;
480 }
481 }
482
483
484 pending_req->sgl = kmalloc_array(nr_segments,
485 sizeof(struct scatterlist), GFP_KERNEL);
486 if (!pending_req->sgl)
487 return -ENOMEM;
488
489 sg_init_table(pending_req->sgl, nr_segments);
490 pending_req->n_sg = nr_segments;
491
492 flags = GNTMAP_host_map;
493 if (pending_req->sc_data_direction == DMA_TO_DEVICE)
494 flags |= GNTMAP_readonly;
495
496 pg = pending_req->pages + nr_sgl;
497 grant = pending_req->grant_handles + nr_sgl;
498 if (!nr_sgl) {
499 seg = ring_req->seg;
500 err = scsiback_gnttab_data_map_list(pending_req, seg,
501 pg, grant, nr_segments, flags);
502 if (err)
503 return err;
504 } else {
505 for (i = 0; i < nr_sgl; i++) {
506 seg = (struct scsiif_request_segment *)(
507 vaddr(pending_req, i) + ring_req->seg[i].offset);
508 n_segs = ring_req->seg[i].length /
509 sizeof(struct scsiif_request_segment);
510 err = scsiback_gnttab_data_map_list(pending_req, seg,
511 pg, grant, n_segs, flags);
512 if (err)
513 return err;
514 pg += n_segs;
515 grant += n_segs;
516 }
517 end_seg = vaddr(pending_req, 0) + ring_req->seg[0].offset;
518 seg = (struct scsiif_request_segment *)end_seg;
519 end_seg += ring_req->seg[0].length;
520 pg = pending_req->pages + nr_sgl;
521 }
522
523 for_each_sg(pending_req->sgl, sg, nr_segments, i) {
524 sg_set_page(sg, pg[i], seg->length, seg->offset);
525 pending_req->data_len += seg->length;
526 seg++;
527 if (nr_sgl && (unsigned long)seg >= end_seg) {
528 i_seg++;
529 end_seg = vaddr(pending_req, i_seg) +
530 ring_req->seg[i_seg].offset;
531 seg = (struct scsiif_request_segment *)end_seg;
532 end_seg += ring_req->seg[i_seg].length;
533 }
534 if (sg->offset >= PAGE_SIZE ||
535 sg->length > PAGE_SIZE ||
536 sg->offset + sg->length > PAGE_SIZE)
537 return -EINVAL;
538 }
539
540 return 0;
541}
542
543static void scsiback_disconnect(struct vscsibk_info *info)
544{
545 wait_event(info->waiting_to_free,
546 atomic_read(&info->nr_unreplied_reqs) == 0);
547
548 unbind_from_irqhandler(info->irq, info);
549 info->irq = 0;
550 xenbus_unmap_ring_vfree(info->dev, info->ring.sring);
551}
552
553static void scsiback_device_action(struct vscsibk_pend *pending_req,
554 enum tcm_tmreq_table act, int tag)
555{
556 struct scsiback_tpg *tpg = pending_req->v2p->tpg;
557 struct scsiback_nexus *nexus = tpg->tpg_nexus;
558 struct se_cmd *se_cmd = &pending_req->se_cmd;
559 u64 unpacked_lun = pending_req->v2p->lun;
560 int rc, err = FAILED;
561
562 init_completion(&pending_req->tmr_done);
563
564 rc = target_submit_tmr(&pending_req->se_cmd, nexus->tvn_se_sess,
565 &pending_req->sense_buffer[0],
566 unpacked_lun, NULL, act, GFP_KERNEL,
567 tag, TARGET_SCF_ACK_KREF);
568 if (rc)
569 goto err;
570
571 wait_for_completion(&pending_req->tmr_done);
572
573 err = (se_cmd->se_tmr_req->response == TMR_FUNCTION_COMPLETE) ?
574 SUCCESS : FAILED;
575
576 scsiback_do_resp_with_sense(NULL, err, 0, pending_req);
577 transport_generic_free_cmd(&pending_req->se_cmd, 0);
578 return;
579
580err:
581 scsiback_do_resp_with_sense(NULL, err, 0, pending_req);
582}
583
584
585
586
587static struct v2p_entry *scsiback_do_translation(struct vscsibk_info *info,
588 struct ids_tuple *v)
589{
590 struct v2p_entry *entry;
591 struct list_head *head = &(info->v2p_entry_lists);
592 unsigned long flags;
593
594 spin_lock_irqsave(&info->v2p_lock, flags);
595 list_for_each_entry(entry, head, l) {
596 if ((entry->v.chn == v->chn) &&
597 (entry->v.tgt == v->tgt) &&
598 (entry->v.lun == v->lun)) {
599 kref_get(&entry->kref);
600 goto out;
601 }
602 }
603 entry = NULL;
604
605out:
606 spin_unlock_irqrestore(&info->v2p_lock, flags);
607 return entry;
608}
609
610static struct vscsibk_pend *scsiback_get_pend_req(struct vscsiif_back_ring *ring,
611 struct v2p_entry *v2p)
612{
613 struct scsiback_tpg *tpg = v2p->tpg;
614 struct scsiback_nexus *nexus = tpg->tpg_nexus;
615 struct se_session *se_sess = nexus->tvn_se_sess;
616 struct vscsibk_pend *req;
617 int tag, cpu, i;
618
619 tag = sbitmap_queue_get(&se_sess->sess_tag_pool, &cpu);
620 if (tag < 0) {
621 pr_err("Unable to obtain tag for vscsiif_request\n");
622 return ERR_PTR(-ENOMEM);
623 }
624
625 req = &((struct vscsibk_pend *)se_sess->sess_cmd_map)[tag];
626 memset(req, 0, sizeof(*req));
627 req->se_cmd.map_tag = tag;
628 req->se_cmd.map_cpu = cpu;
629
630 for (i = 0; i < VSCSI_MAX_GRANTS; i++)
631 req->grant_handles[i] = SCSIBACK_INVALID_HANDLE;
632
633 return req;
634}
635
636static struct vscsibk_pend *prepare_pending_reqs(struct vscsibk_info *info,
637 struct vscsiif_back_ring *ring,
638 struct vscsiif_request *ring_req)
639{
640 struct vscsibk_pend *pending_req;
641 struct v2p_entry *v2p;
642 struct ids_tuple vir;
643
644
645 if ((ring_req->sc_data_direction != DMA_BIDIRECTIONAL) &&
646 (ring_req->sc_data_direction != DMA_TO_DEVICE) &&
647 (ring_req->sc_data_direction != DMA_FROM_DEVICE) &&
648 (ring_req->sc_data_direction != DMA_NONE)) {
649 pr_debug("invalid parameter data_dir = %d\n",
650 ring_req->sc_data_direction);
651 return ERR_PTR(-EINVAL);
652 }
653 if (ring_req->cmd_len > VSCSIIF_MAX_COMMAND_SIZE) {
654 pr_debug("invalid parameter cmd_len = %d\n",
655 ring_req->cmd_len);
656 return ERR_PTR(-EINVAL);
657 }
658
659 vir.chn = ring_req->channel;
660 vir.tgt = ring_req->id;
661 vir.lun = ring_req->lun;
662
663 v2p = scsiback_do_translation(info, &vir);
664 if (!v2p) {
665 pr_debug("the v2p of (chn:%d, tgt:%d, lun:%d) doesn't exist.\n",
666 vir.chn, vir.tgt, vir.lun);
667 return ERR_PTR(-ENODEV);
668 }
669
670 pending_req = scsiback_get_pend_req(ring, v2p);
671 if (IS_ERR(pending_req)) {
672 kref_put(&v2p->kref, scsiback_free_translation_entry);
673 return ERR_PTR(-ENOMEM);
674 }
675 pending_req->rqid = ring_req->rqid;
676 pending_req->info = info;
677 pending_req->v2p = v2p;
678 pending_req->sc_data_direction = ring_req->sc_data_direction;
679 pending_req->cmd_len = ring_req->cmd_len;
680 memcpy(pending_req->cmnd, ring_req->cmnd, pending_req->cmd_len);
681
682 return pending_req;
683}
684
685static int scsiback_do_cmd_fn(struct vscsibk_info *info,
686 unsigned int *eoi_flags)
687{
688 struct vscsiif_back_ring *ring = &info->ring;
689 struct vscsiif_request ring_req;
690 struct vscsibk_pend *pending_req;
691 RING_IDX rc, rp;
692 int more_to_do;
693 uint32_t result;
694
695 rc = ring->req_cons;
696 rp = ring->sring->req_prod;
697 rmb();
698
699 if (RING_REQUEST_PROD_OVERFLOW(ring, rp)) {
700 rc = ring->rsp_prod_pvt;
701 pr_warn("Dom%d provided bogus ring requests (%#x - %#x = %u). Halting ring processing\n",
702 info->domid, rp, rc, rp - rc);
703 return -EINVAL;
704 }
705
706 while ((rc != rp)) {
707 *eoi_flags &= ~XEN_EOI_FLAG_SPURIOUS;
708
709 if (RING_REQUEST_CONS_OVERFLOW(ring, rc))
710 break;
711
712 RING_COPY_REQUEST(ring, rc, &ring_req);
713 ring->req_cons = ++rc;
714
715 pending_req = prepare_pending_reqs(info, ring, &ring_req);
716 if (IS_ERR(pending_req)) {
717 switch (PTR_ERR(pending_req)) {
718 case -ENODEV:
719 result = DID_NO_CONNECT;
720 break;
721 default:
722 result = DID_ERROR;
723 break;
724 }
725 scsiback_send_response(info, NULL, result << 16, 0,
726 ring_req.rqid);
727 return 1;
728 }
729
730 switch (ring_req.act) {
731 case VSCSIIF_ACT_SCSI_CDB:
732 if (scsiback_gnttab_data_map(&ring_req, pending_req)) {
733 scsiback_fast_flush_area(pending_req);
734 scsiback_do_resp_with_sense(NULL,
735 DID_ERROR << 16, 0, pending_req);
736 transport_generic_free_cmd(&pending_req->se_cmd, 0);
737 } else {
738 scsiback_cmd_exec(pending_req);
739 }
740 break;
741 case VSCSIIF_ACT_SCSI_ABORT:
742 scsiback_device_action(pending_req, TMR_ABORT_TASK,
743 ring_req.ref_rqid);
744 break;
745 case VSCSIIF_ACT_SCSI_RESET:
746 scsiback_device_action(pending_req, TMR_LUN_RESET, 0);
747 break;
748 default:
749 pr_err_ratelimited("invalid request\n");
750 scsiback_do_resp_with_sense(NULL, DID_ERROR << 16, 0,
751 pending_req);
752 transport_generic_free_cmd(&pending_req->se_cmd, 0);
753 break;
754 }
755
756
757 cond_resched();
758 }
759
760 gnttab_page_cache_shrink(&info->free_pages, scsiback_max_buffer_pages);
761
762 RING_FINAL_CHECK_FOR_REQUESTS(&info->ring, more_to_do);
763 return more_to_do;
764}
765
766static irqreturn_t scsiback_irq_fn(int irq, void *dev_id)
767{
768 struct vscsibk_info *info = dev_id;
769 int rc;
770 unsigned int eoi_flags = XEN_EOI_FLAG_SPURIOUS;
771
772 while ((rc = scsiback_do_cmd_fn(info, &eoi_flags)) > 0)
773 cond_resched();
774
775
776 if (!rc)
777 xen_irq_lateeoi(irq, eoi_flags);
778
779 return IRQ_HANDLED;
780}
781
782static int scsiback_init_sring(struct vscsibk_info *info, grant_ref_t ring_ref,
783 evtchn_port_t evtchn)
784{
785 void *area;
786 struct vscsiif_sring *sring;
787 int err;
788
789 if (info->irq)
790 return -1;
791
792 err = xenbus_map_ring_valloc(info->dev, &ring_ref, 1, &area);
793 if (err)
794 return err;
795
796 sring = (struct vscsiif_sring *)area;
797 BACK_RING_INIT(&info->ring, sring, PAGE_SIZE);
798
799 err = bind_interdomain_evtchn_to_irq_lateeoi(info->dev, evtchn);
800 if (err < 0)
801 goto unmap_page;
802
803 info->irq = err;
804
805 err = request_threaded_irq(info->irq, NULL, scsiback_irq_fn,
806 IRQF_ONESHOT, "vscsiif-backend", info);
807 if (err)
808 goto free_irq;
809
810 return 0;
811
812free_irq:
813 unbind_from_irqhandler(info->irq, info);
814 info->irq = 0;
815unmap_page:
816 xenbus_unmap_ring_vfree(info->dev, area);
817
818 return err;
819}
820
821static int scsiback_map(struct vscsibk_info *info)
822{
823 struct xenbus_device *dev = info->dev;
824 unsigned int ring_ref;
825 evtchn_port_t evtchn;
826 int err;
827
828 err = xenbus_gather(XBT_NIL, dev->otherend,
829 "ring-ref", "%u", &ring_ref,
830 "event-channel", "%u", &evtchn, NULL);
831 if (err) {
832 xenbus_dev_fatal(dev, err, "reading %s ring", dev->otherend);
833 return err;
834 }
835
836 return scsiback_init_sring(info, ring_ref, evtchn);
837}
838
839
840
841
842static struct v2p_entry *scsiback_chk_translation_entry(
843 struct vscsibk_info *info, struct ids_tuple *v)
844{
845 struct list_head *head = &(info->v2p_entry_lists);
846 struct v2p_entry *entry;
847
848 list_for_each_entry(entry, head, l)
849 if ((entry->v.chn == v->chn) &&
850 (entry->v.tgt == v->tgt) &&
851 (entry->v.lun == v->lun))
852 return entry;
853
854 return NULL;
855}
856
857
858
859
860static 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 *new;
865 unsigned long flags;
866 char *lunp;
867 unsigned long long unpacked_lun;
868 struct se_lun *se_lun;
869 struct scsiback_tpg *tpg_entry, *tpg = NULL;
870 char *error = "doesn't exist";
871
872 lunp = strrchr(phy, ':');
873 if (!lunp) {
874 pr_err("illegal format of physical device %s\n", phy);
875 return -EINVAL;
876 }
877 *lunp = 0;
878 lunp++;
879 err = kstrtoull(lunp, 10, &unpacked_lun);
880 if (err < 0) {
881 pr_err("lun number not valid: %s\n", lunp);
882 return err;
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 mutex_lock(&tpg_entry->se_tpg.tpg_lun_mutex);
890 hlist_for_each_entry(se_lun, &tpg_entry->se_tpg.tpg_lun_hlist, link) {
891 if (se_lun->unpacked_lun == unpacked_lun) {
892 if (!tpg_entry->tpg_nexus)
893 error = "nexus undefined";
894 else
895 tpg = tpg_entry;
896 break;
897 }
898 }
899 mutex_unlock(&tpg_entry->se_tpg.tpg_lun_mutex);
900 break;
901 }
902 }
903 if (tpg) {
904 mutex_lock(&tpg->tv_tpg_mutex);
905 tpg->tv_tpg_fe_count++;
906 mutex_unlock(&tpg->tv_tpg_mutex);
907 }
908 mutex_unlock(&scsiback_mutex);
909
910 if (!tpg) {
911 pr_err("%s:%llu %s\n", phy, unpacked_lun, error);
912 return -ENODEV;
913 }
914
915 new = kmalloc(sizeof(struct v2p_entry), GFP_KERNEL);
916 if (new == NULL) {
917 err = -ENOMEM;
918 goto out_free;
919 }
920
921 spin_lock_irqsave(&info->v2p_lock, flags);
922
923
924 if (scsiback_chk_translation_entry(info, v)) {
925 pr_warn("Virtual ID is already used. Assignment was not performed.\n");
926 err = -EEXIST;
927 goto out;
928 }
929
930
931 kref_init(&new->kref);
932 new->v = *v;
933 new->tpg = tpg;
934 new->lun = unpacked_lun;
935 list_add_tail(&new->l, &info->v2p_entry_lists);
936
937out:
938 spin_unlock_irqrestore(&info->v2p_lock, flags);
939
940out_free:
941 if (err) {
942 mutex_lock(&tpg->tv_tpg_mutex);
943 tpg->tv_tpg_fe_count--;
944 mutex_unlock(&tpg->tv_tpg_mutex);
945 kfree(new);
946 }
947
948 return err;
949}
950
951static void __scsiback_del_translation_entry(struct v2p_entry *entry)
952{
953 list_del(&entry->l);
954 kref_put(&entry->kref, scsiback_free_translation_entry);
955}
956
957
958
959
960static int scsiback_del_translation_entry(struct vscsibk_info *info,
961 struct ids_tuple *v)
962{
963 struct v2p_entry *entry;
964 unsigned long flags;
965 int ret = 0;
966
967 spin_lock_irqsave(&info->v2p_lock, flags);
968
969 entry = scsiback_chk_translation_entry(info, v);
970 if (entry)
971 __scsiback_del_translation_entry(entry);
972 else
973 ret = -ENOENT;
974
975 spin_unlock_irqrestore(&info->v2p_lock, flags);
976 return ret;
977}
978
979static void scsiback_do_add_lun(struct vscsibk_info *info, const char *state,
980 char *phy, struct ids_tuple *vir, int try)
981{
982 struct v2p_entry *entry;
983 unsigned long flags;
984 int err;
985
986 if (try) {
987 spin_lock_irqsave(&info->v2p_lock, flags);
988 entry = scsiback_chk_translation_entry(info, vir);
989 spin_unlock_irqrestore(&info->v2p_lock, flags);
990 if (entry)
991 return;
992 }
993 if (!scsiback_add_translation_entry(info, phy, vir)) {
994 if (xenbus_printf(XBT_NIL, info->dev->nodename, state,
995 "%d", XenbusStateInitialised)) {
996 pr_err("xenbus_printf error %s\n", state);
997 scsiback_del_translation_entry(info, vir);
998 }
999 } else if (!try) {
1000 err = xenbus_printf(XBT_NIL, info->dev->nodename, state,
1001 "%d", XenbusStateClosed);
1002 if (err)
1003 xenbus_dev_error(info->dev, err,
1004 "%s: writing %s", __func__, state);
1005 }
1006}
1007
1008static void scsiback_do_del_lun(struct vscsibk_info *info, const char *state,
1009 struct ids_tuple *vir)
1010{
1011 if (!scsiback_del_translation_entry(info, vir)) {
1012 if (xenbus_printf(XBT_NIL, info->dev->nodename, state,
1013 "%d", XenbusStateClosed))
1014 pr_err("xenbus_printf error %s\n", state);
1015 }
1016}
1017
1018#define VSCSIBACK_OP_ADD_OR_DEL_LUN 1
1019#define VSCSIBACK_OP_UPDATEDEV_STATE 2
1020
1021static void scsiback_do_1lun_hotplug(struct vscsibk_info *info, int op,
1022 char *ent)
1023{
1024 int err;
1025 struct ids_tuple vir;
1026 char *val;
1027 int device_state;
1028 char phy[VSCSI_NAMELEN];
1029 char str[64];
1030 char state[64];
1031 struct xenbus_device *dev = info->dev;
1032
1033
1034 snprintf(state, sizeof(state), "vscsi-devs/%s/state", ent);
1035 err = xenbus_scanf(XBT_NIL, dev->nodename, state, "%u", &device_state);
1036 if (XENBUS_EXIST_ERR(err))
1037 return;
1038
1039
1040 snprintf(str, sizeof(str), "vscsi-devs/%s/p-dev", ent);
1041 val = xenbus_read(XBT_NIL, dev->nodename, str, NULL);
1042 if (IS_ERR(val)) {
1043 err = xenbus_printf(XBT_NIL, dev->nodename, state,
1044 "%d", XenbusStateClosed);
1045 if (err)
1046 xenbus_dev_error(info->dev, err,
1047 "%s: writing %s", __func__, state);
1048 return;
1049 }
1050 strlcpy(phy, val, VSCSI_NAMELEN);
1051 kfree(val);
1052
1053
1054 snprintf(str, sizeof(str), "vscsi-devs/%s/v-dev", ent);
1055 err = xenbus_scanf(XBT_NIL, dev->nodename, str, "%u:%u:%u:%u",
1056 &vir.hst, &vir.chn, &vir.tgt, &vir.lun);
1057 if (XENBUS_EXIST_ERR(err)) {
1058 err = xenbus_printf(XBT_NIL, dev->nodename, state,
1059 "%d", XenbusStateClosed);
1060 if (err)
1061 xenbus_dev_error(info->dev, err,
1062 "%s: writing %s", __func__, state);
1063 return;
1064 }
1065
1066 switch (op) {
1067 case VSCSIBACK_OP_ADD_OR_DEL_LUN:
1068 switch (device_state) {
1069 case XenbusStateInitialising:
1070 scsiback_do_add_lun(info, state, phy, &vir, 0);
1071 break;
1072 case XenbusStateConnected:
1073 scsiback_do_add_lun(info, state, phy, &vir, 1);
1074 break;
1075 case XenbusStateClosing:
1076 scsiback_do_del_lun(info, state, &vir);
1077 break;
1078 default:
1079 break;
1080 }
1081 break;
1082
1083 case VSCSIBACK_OP_UPDATEDEV_STATE:
1084 if (device_state == XenbusStateInitialised) {
1085
1086 if (xenbus_printf(XBT_NIL, dev->nodename, state,
1087 "%d", XenbusStateConnected)) {
1088 pr_err("xenbus_printf error %s\n", str);
1089 scsiback_del_translation_entry(info, &vir);
1090 xenbus_printf(XBT_NIL, dev->nodename, state,
1091 "%d", XenbusStateClosed);
1092 }
1093 }
1094 break;
1095
1096 default:
1097 break;
1098 }
1099}
1100
1101static void scsiback_do_lun_hotplug(struct vscsibk_info *info, int op)
1102{
1103 int i;
1104 char **dir;
1105 unsigned int ndir = 0;
1106
1107 dir = xenbus_directory(XBT_NIL, info->dev->nodename, "vscsi-devs",
1108 &ndir);
1109 if (IS_ERR(dir))
1110 return;
1111
1112 for (i = 0; i < ndir; i++)
1113 scsiback_do_1lun_hotplug(info, op, dir[i]);
1114
1115 kfree(dir);
1116}
1117
1118static void scsiback_frontend_changed(struct xenbus_device *dev,
1119 enum xenbus_state frontend_state)
1120{
1121 struct vscsibk_info *info = dev_get_drvdata(&dev->dev);
1122
1123 switch (frontend_state) {
1124 case XenbusStateInitialising:
1125 break;
1126
1127 case XenbusStateInitialised:
1128 if (scsiback_map(info))
1129 break;
1130
1131 scsiback_do_lun_hotplug(info, VSCSIBACK_OP_ADD_OR_DEL_LUN);
1132 xenbus_switch_state(dev, XenbusStateConnected);
1133 break;
1134
1135 case XenbusStateConnected:
1136 scsiback_do_lun_hotplug(info, VSCSIBACK_OP_UPDATEDEV_STATE);
1137
1138 if (dev->state == XenbusStateConnected)
1139 break;
1140
1141 xenbus_switch_state(dev, XenbusStateConnected);
1142 break;
1143
1144 case XenbusStateClosing:
1145 if (info->irq)
1146 scsiback_disconnect(info);
1147
1148 xenbus_switch_state(dev, XenbusStateClosing);
1149 break;
1150
1151 case XenbusStateClosed:
1152 xenbus_switch_state(dev, XenbusStateClosed);
1153 if (xenbus_dev_is_online(dev))
1154 break;
1155 fallthrough;
1156 case XenbusStateUnknown:
1157 device_unregister(&dev->dev);
1158 break;
1159
1160 case XenbusStateReconfiguring:
1161 scsiback_do_lun_hotplug(info, VSCSIBACK_OP_ADD_OR_DEL_LUN);
1162 xenbus_switch_state(dev, XenbusStateReconfigured);
1163
1164 break;
1165
1166 default:
1167 xenbus_dev_fatal(dev, -EINVAL, "saw state %d at frontend",
1168 frontend_state);
1169 break;
1170 }
1171}
1172
1173
1174
1175
1176static void scsiback_release_translation_entry(struct vscsibk_info *info)
1177{
1178 struct v2p_entry *entry, *tmp;
1179 struct list_head *head = &(info->v2p_entry_lists);
1180 unsigned long flags;
1181
1182 spin_lock_irqsave(&info->v2p_lock, flags);
1183
1184 list_for_each_entry_safe(entry, tmp, head, l)
1185 __scsiback_del_translation_entry(entry);
1186
1187 spin_unlock_irqrestore(&info->v2p_lock, flags);
1188}
1189
1190static int scsiback_remove(struct xenbus_device *dev)
1191{
1192 struct vscsibk_info *info = dev_get_drvdata(&dev->dev);
1193
1194 if (info->irq)
1195 scsiback_disconnect(info);
1196
1197 scsiback_release_translation_entry(info);
1198
1199 gnttab_page_cache_shrink(&info->free_pages, 0);
1200
1201 dev_set_drvdata(&dev->dev, NULL);
1202
1203 return 0;
1204}
1205
1206static int scsiback_probe(struct xenbus_device *dev,
1207 const struct xenbus_device_id *id)
1208{
1209 int err;
1210
1211 struct vscsibk_info *info = kzalloc(sizeof(struct vscsibk_info),
1212 GFP_KERNEL);
1213
1214 pr_debug("%s %p %d\n", __func__, dev, dev->otherend_id);
1215
1216 if (!info) {
1217 xenbus_dev_fatal(dev, -ENOMEM, "allocating backend structure");
1218 return -ENOMEM;
1219 }
1220 info->dev = dev;
1221 dev_set_drvdata(&dev->dev, info);
1222
1223 info->domid = dev->otherend_id;
1224 spin_lock_init(&info->ring_lock);
1225 atomic_set(&info->nr_unreplied_reqs, 0);
1226 init_waitqueue_head(&info->waiting_to_free);
1227 info->dev = dev;
1228 info->irq = 0;
1229 INIT_LIST_HEAD(&info->v2p_entry_lists);
1230 spin_lock_init(&info->v2p_lock);
1231 gnttab_page_cache_init(&info->free_pages);
1232
1233 err = xenbus_printf(XBT_NIL, dev->nodename, "feature-sg-grant", "%u",
1234 SG_ALL);
1235 if (err)
1236 xenbus_dev_error(dev, err, "writing feature-sg-grant");
1237
1238 err = xenbus_switch_state(dev, XenbusStateInitWait);
1239 if (err)
1240 goto fail;
1241
1242 return 0;
1243
1244fail:
1245 pr_warn("%s failed\n", __func__);
1246 scsiback_remove(dev);
1247
1248 return err;
1249}
1250
1251static char *scsiback_dump_proto_id(struct scsiback_tport *tport)
1252{
1253 switch (tport->tport_proto_id) {
1254 case SCSI_PROTOCOL_SAS:
1255 return "SAS";
1256 case SCSI_PROTOCOL_FCP:
1257 return "FCP";
1258 case SCSI_PROTOCOL_ISCSI:
1259 return "iSCSI";
1260 default:
1261 break;
1262 }
1263
1264 return "Unknown";
1265}
1266
1267static char *scsiback_get_fabric_wwn(struct se_portal_group *se_tpg)
1268{
1269 struct scsiback_tpg *tpg = container_of(se_tpg,
1270 struct scsiback_tpg, se_tpg);
1271 struct scsiback_tport *tport = tpg->tport;
1272
1273 return &tport->tport_name[0];
1274}
1275
1276static u16 scsiback_get_tag(struct se_portal_group *se_tpg)
1277{
1278 struct scsiback_tpg *tpg = container_of(se_tpg,
1279 struct scsiback_tpg, se_tpg);
1280 return tpg->tport_tpgt;
1281}
1282
1283static struct se_wwn *
1284scsiback_make_tport(struct target_fabric_configfs *tf,
1285 struct config_group *group,
1286 const char *name)
1287{
1288 struct scsiback_tport *tport;
1289 char *ptr;
1290 u64 wwpn = 0;
1291 int off = 0;
1292
1293 tport = kzalloc(sizeof(struct scsiback_tport), GFP_KERNEL);
1294 if (!tport)
1295 return ERR_PTR(-ENOMEM);
1296
1297 tport->tport_wwpn = wwpn;
1298
1299
1300
1301
1302 ptr = strstr(name, "naa.");
1303 if (ptr) {
1304 tport->tport_proto_id = SCSI_PROTOCOL_SAS;
1305 goto check_len;
1306 }
1307 ptr = strstr(name, "fc.");
1308 if (ptr) {
1309 tport->tport_proto_id = SCSI_PROTOCOL_FCP;
1310 off = 3;
1311 goto check_len;
1312 }
1313 ptr = strstr(name, "iqn.");
1314 if (ptr) {
1315 tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
1316 goto check_len;
1317 }
1318
1319 pr_err("Unable to locate prefix for emulated Target Port: %s\n", name);
1320 kfree(tport);
1321 return ERR_PTR(-EINVAL);
1322
1323check_len:
1324 if (strlen(name) >= VSCSI_NAMELEN) {
1325 pr_err("Emulated %s Address: %s, exceeds max: %d\n", name,
1326 scsiback_dump_proto_id(tport), VSCSI_NAMELEN);
1327 kfree(tport);
1328 return ERR_PTR(-EINVAL);
1329 }
1330 snprintf(&tport->tport_name[0], VSCSI_NAMELEN, "%s", &name[off]);
1331
1332 pr_debug("Allocated emulated Target %s Address: %s\n",
1333 scsiback_dump_proto_id(tport), name);
1334
1335 return &tport->tport_wwn;
1336}
1337
1338static void scsiback_drop_tport(struct se_wwn *wwn)
1339{
1340 struct scsiback_tport *tport = container_of(wwn,
1341 struct scsiback_tport, tport_wwn);
1342
1343 pr_debug("Deallocating emulated Target %s Address: %s\n",
1344 scsiback_dump_proto_id(tport), tport->tport_name);
1345
1346 kfree(tport);
1347}
1348
1349static u32 scsiback_tpg_get_inst_index(struct se_portal_group *se_tpg)
1350{
1351 return 1;
1352}
1353
1354static int scsiback_check_stop_free(struct se_cmd *se_cmd)
1355{
1356 return transport_generic_free_cmd(se_cmd, 0);
1357}
1358
1359static void scsiback_release_cmd(struct se_cmd *se_cmd)
1360{
1361 target_free_tag(se_cmd->se_sess, se_cmd);
1362}
1363
1364static u32 scsiback_sess_get_index(struct se_session *se_sess)
1365{
1366 return 0;
1367}
1368
1369static int scsiback_write_pending(struct se_cmd *se_cmd)
1370{
1371
1372 target_execute_cmd(se_cmd);
1373
1374 return 0;
1375}
1376
1377static void scsiback_set_default_node_attrs(struct se_node_acl *nacl)
1378{
1379}
1380
1381static int scsiback_get_cmd_state(struct se_cmd *se_cmd)
1382{
1383 return 0;
1384}
1385
1386static int scsiback_queue_data_in(struct se_cmd *se_cmd)
1387{
1388 struct vscsibk_pend *pending_req = container_of(se_cmd,
1389 struct vscsibk_pend, se_cmd);
1390
1391 pending_req->result = SAM_STAT_GOOD;
1392 scsiback_cmd_done(pending_req);
1393 return 0;
1394}
1395
1396static int scsiback_queue_status(struct se_cmd *se_cmd)
1397{
1398 struct vscsibk_pend *pending_req = container_of(se_cmd,
1399 struct vscsibk_pend, se_cmd);
1400
1401 if (se_cmd->sense_buffer &&
1402 ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
1403 (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE)))
1404 pending_req->result = SAM_STAT_CHECK_CONDITION;
1405 else
1406 pending_req->result = se_cmd->scsi_status;
1407
1408 scsiback_cmd_done(pending_req);
1409 return 0;
1410}
1411
1412static void scsiback_queue_tm_rsp(struct se_cmd *se_cmd)
1413{
1414 struct vscsibk_pend *pending_req = container_of(se_cmd,
1415 struct vscsibk_pend, se_cmd);
1416
1417 complete(&pending_req->tmr_done);
1418}
1419
1420static void scsiback_aborted_task(struct se_cmd *se_cmd)
1421{
1422}
1423
1424static ssize_t scsiback_tpg_param_alias_show(struct config_item *item,
1425 char *page)
1426{
1427 struct se_portal_group *se_tpg = param_to_tpg(item);
1428 struct scsiback_tpg *tpg = container_of(se_tpg, struct scsiback_tpg,
1429 se_tpg);
1430 ssize_t rb;
1431
1432 mutex_lock(&tpg->tv_tpg_mutex);
1433 rb = snprintf(page, PAGE_SIZE, "%s\n", tpg->param_alias);
1434 mutex_unlock(&tpg->tv_tpg_mutex);
1435
1436 return rb;
1437}
1438
1439static ssize_t scsiback_tpg_param_alias_store(struct config_item *item,
1440 const char *page, size_t count)
1441{
1442 struct se_portal_group *se_tpg = param_to_tpg(item);
1443 struct scsiback_tpg *tpg = container_of(se_tpg, struct scsiback_tpg,
1444 se_tpg);
1445 int len;
1446
1447 if (strlen(page) >= VSCSI_NAMELEN) {
1448 pr_err("param alias: %s, exceeds max: %d\n", page,
1449 VSCSI_NAMELEN);
1450 return -EINVAL;
1451 }
1452
1453 mutex_lock(&tpg->tv_tpg_mutex);
1454 len = snprintf(tpg->param_alias, VSCSI_NAMELEN, "%s", page);
1455 if (tpg->param_alias[len - 1] == '\n')
1456 tpg->param_alias[len - 1] = '\0';
1457 mutex_unlock(&tpg->tv_tpg_mutex);
1458
1459 return count;
1460}
1461
1462CONFIGFS_ATTR(scsiback_tpg_param_, alias);
1463
1464static struct configfs_attribute *scsiback_param_attrs[] = {
1465 &scsiback_tpg_param_attr_alias,
1466 NULL,
1467};
1468
1469static int scsiback_alloc_sess_cb(struct se_portal_group *se_tpg,
1470 struct se_session *se_sess, void *p)
1471{
1472 struct scsiback_tpg *tpg = container_of(se_tpg,
1473 struct scsiback_tpg, se_tpg);
1474
1475 tpg->tpg_nexus = p;
1476 return 0;
1477}
1478
1479static int scsiback_make_nexus(struct scsiback_tpg *tpg,
1480 const char *name)
1481{
1482 struct scsiback_nexus *tv_nexus;
1483 int ret = 0;
1484
1485 mutex_lock(&tpg->tv_tpg_mutex);
1486 if (tpg->tpg_nexus) {
1487 pr_debug("tpg->tpg_nexus already exists\n");
1488 ret = -EEXIST;
1489 goto out_unlock;
1490 }
1491
1492 tv_nexus = kzalloc(sizeof(struct scsiback_nexus), GFP_KERNEL);
1493 if (!tv_nexus) {
1494 ret = -ENOMEM;
1495 goto out_unlock;
1496 }
1497
1498 tv_nexus->tvn_se_sess = target_setup_session(&tpg->se_tpg,
1499 VSCSI_DEFAULT_SESSION_TAGS,
1500 sizeof(struct vscsibk_pend),
1501 TARGET_PROT_NORMAL, name,
1502 tv_nexus, scsiback_alloc_sess_cb);
1503 if (IS_ERR(tv_nexus->tvn_se_sess)) {
1504 kfree(tv_nexus);
1505 ret = -ENOMEM;
1506 goto out_unlock;
1507 }
1508
1509out_unlock:
1510 mutex_unlock(&tpg->tv_tpg_mutex);
1511 return ret;
1512}
1513
1514static int scsiback_drop_nexus(struct scsiback_tpg *tpg)
1515{
1516 struct se_session *se_sess;
1517 struct scsiback_nexus *tv_nexus;
1518
1519 mutex_lock(&tpg->tv_tpg_mutex);
1520 tv_nexus = tpg->tpg_nexus;
1521 if (!tv_nexus) {
1522 mutex_unlock(&tpg->tv_tpg_mutex);
1523 return -ENODEV;
1524 }
1525
1526 se_sess = tv_nexus->tvn_se_sess;
1527 if (!se_sess) {
1528 mutex_unlock(&tpg->tv_tpg_mutex);
1529 return -ENODEV;
1530 }
1531
1532 if (tpg->tv_tpg_port_count != 0) {
1533 mutex_unlock(&tpg->tv_tpg_mutex);
1534 pr_err("Unable to remove xen-pvscsi I_T Nexus with active TPG port count: %d\n",
1535 tpg->tv_tpg_port_count);
1536 return -EBUSY;
1537 }
1538
1539 if (tpg->tv_tpg_fe_count != 0) {
1540 mutex_unlock(&tpg->tv_tpg_mutex);
1541 pr_err("Unable to remove xen-pvscsi I_T Nexus with active TPG frontend count: %d\n",
1542 tpg->tv_tpg_fe_count);
1543 return -EBUSY;
1544 }
1545
1546 pr_debug("Removing I_T Nexus to emulated %s Initiator Port: %s\n",
1547 scsiback_dump_proto_id(tpg->tport),
1548 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1549
1550
1551
1552
1553 target_remove_session(se_sess);
1554 tpg->tpg_nexus = NULL;
1555 mutex_unlock(&tpg->tv_tpg_mutex);
1556
1557 kfree(tv_nexus);
1558 return 0;
1559}
1560
1561static ssize_t scsiback_tpg_nexus_show(struct config_item *item, char *page)
1562{
1563 struct se_portal_group *se_tpg = to_tpg(item);
1564 struct scsiback_tpg *tpg = container_of(se_tpg,
1565 struct scsiback_tpg, se_tpg);
1566 struct scsiback_nexus *tv_nexus;
1567 ssize_t ret;
1568
1569 mutex_lock(&tpg->tv_tpg_mutex);
1570 tv_nexus = tpg->tpg_nexus;
1571 if (!tv_nexus) {
1572 mutex_unlock(&tpg->tv_tpg_mutex);
1573 return -ENODEV;
1574 }
1575 ret = snprintf(page, PAGE_SIZE, "%s\n",
1576 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1577 mutex_unlock(&tpg->tv_tpg_mutex);
1578
1579 return ret;
1580}
1581
1582static ssize_t scsiback_tpg_nexus_store(struct config_item *item,
1583 const char *page, size_t count)
1584{
1585 struct se_portal_group *se_tpg = to_tpg(item);
1586 struct scsiback_tpg *tpg = container_of(se_tpg,
1587 struct scsiback_tpg, se_tpg);
1588 struct scsiback_tport *tport_wwn = tpg->tport;
1589 unsigned char i_port[VSCSI_NAMELEN], *ptr, *port_ptr;
1590 int ret;
1591
1592
1593
1594 if (!strncmp(page, "NULL", 4)) {
1595 ret = scsiback_drop_nexus(tpg);
1596 return (!ret) ? count : ret;
1597 }
1598
1599
1600
1601
1602
1603 if (strlen(page) >= VSCSI_NAMELEN) {
1604 pr_err("Emulated NAA Sas Address: %s, exceeds max: %d\n",
1605 page, VSCSI_NAMELEN);
1606 return -EINVAL;
1607 }
1608 snprintf(&i_port[0], VSCSI_NAMELEN, "%s", page);
1609
1610 ptr = strstr(i_port, "naa.");
1611 if (ptr) {
1612 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
1613 pr_err("Passed SAS Initiator Port %s does not match target port protoid: %s\n",
1614 i_port, scsiback_dump_proto_id(tport_wwn));
1615 return -EINVAL;
1616 }
1617 port_ptr = &i_port[0];
1618 goto check_newline;
1619 }
1620 ptr = strstr(i_port, "fc.");
1621 if (ptr) {
1622 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
1623 pr_err("Passed FCP Initiator Port %s does not match target port protoid: %s\n",
1624 i_port, scsiback_dump_proto_id(tport_wwn));
1625 return -EINVAL;
1626 }
1627 port_ptr = &i_port[3];
1628 goto check_newline;
1629 }
1630 ptr = strstr(i_port, "iqn.");
1631 if (ptr) {
1632 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
1633 pr_err("Passed iSCSI Initiator Port %s does not match target port protoid: %s\n",
1634 i_port, scsiback_dump_proto_id(tport_wwn));
1635 return -EINVAL;
1636 }
1637 port_ptr = &i_port[0];
1638 goto check_newline;
1639 }
1640 pr_err("Unable to locate prefix for emulated Initiator Port: %s\n",
1641 i_port);
1642 return -EINVAL;
1643
1644
1645
1646check_newline:
1647 if (i_port[strlen(i_port) - 1] == '\n')
1648 i_port[strlen(i_port) - 1] = '\0';
1649
1650 ret = scsiback_make_nexus(tpg, port_ptr);
1651 if (ret < 0)
1652 return ret;
1653
1654 return count;
1655}
1656
1657CONFIGFS_ATTR(scsiback_tpg_, nexus);
1658
1659static struct configfs_attribute *scsiback_tpg_attrs[] = {
1660 &scsiback_tpg_attr_nexus,
1661 NULL,
1662};
1663
1664static ssize_t
1665scsiback_wwn_version_show(struct config_item *item, char *page)
1666{
1667 return sprintf(page, "xen-pvscsi fabric module %s on %s/%s on "
1668 UTS_RELEASE"\n",
1669 VSCSI_VERSION, utsname()->sysname, utsname()->machine);
1670}
1671
1672CONFIGFS_ATTR_RO(scsiback_wwn_, version);
1673
1674static struct configfs_attribute *scsiback_wwn_attrs[] = {
1675 &scsiback_wwn_attr_version,
1676 NULL,
1677};
1678
1679static int scsiback_port_link(struct se_portal_group *se_tpg,
1680 struct se_lun *lun)
1681{
1682 struct scsiback_tpg *tpg = container_of(se_tpg,
1683 struct scsiback_tpg, se_tpg);
1684
1685 mutex_lock(&tpg->tv_tpg_mutex);
1686 tpg->tv_tpg_port_count++;
1687 mutex_unlock(&tpg->tv_tpg_mutex);
1688
1689 return 0;
1690}
1691
1692static void scsiback_port_unlink(struct se_portal_group *se_tpg,
1693 struct se_lun *lun)
1694{
1695 struct scsiback_tpg *tpg = container_of(se_tpg,
1696 struct scsiback_tpg, se_tpg);
1697
1698 mutex_lock(&tpg->tv_tpg_mutex);
1699 tpg->tv_tpg_port_count--;
1700 mutex_unlock(&tpg->tv_tpg_mutex);
1701}
1702
1703static struct se_portal_group *
1704scsiback_make_tpg(struct se_wwn *wwn, const char *name)
1705{
1706 struct scsiback_tport *tport = container_of(wwn,
1707 struct scsiback_tport, tport_wwn);
1708
1709 struct scsiback_tpg *tpg;
1710 u16 tpgt;
1711 int ret;
1712
1713 if (strstr(name, "tpgt_") != name)
1714 return ERR_PTR(-EINVAL);
1715 ret = kstrtou16(name + 5, 10, &tpgt);
1716 if (ret)
1717 return ERR_PTR(ret);
1718
1719 tpg = kzalloc(sizeof(struct scsiback_tpg), GFP_KERNEL);
1720 if (!tpg)
1721 return ERR_PTR(-ENOMEM);
1722
1723 mutex_init(&tpg->tv_tpg_mutex);
1724 INIT_LIST_HEAD(&tpg->tv_tpg_list);
1725 INIT_LIST_HEAD(&tpg->info_list);
1726 tpg->tport = tport;
1727 tpg->tport_tpgt = tpgt;
1728
1729 ret = core_tpg_register(wwn, &tpg->se_tpg, tport->tport_proto_id);
1730 if (ret < 0) {
1731 kfree(tpg);
1732 return NULL;
1733 }
1734 mutex_lock(&scsiback_mutex);
1735 list_add_tail(&tpg->tv_tpg_list, &scsiback_list);
1736 mutex_unlock(&scsiback_mutex);
1737
1738 return &tpg->se_tpg;
1739}
1740
1741static void scsiback_drop_tpg(struct se_portal_group *se_tpg)
1742{
1743 struct scsiback_tpg *tpg = container_of(se_tpg,
1744 struct scsiback_tpg, se_tpg);
1745
1746 mutex_lock(&scsiback_mutex);
1747 list_del(&tpg->tv_tpg_list);
1748 mutex_unlock(&scsiback_mutex);
1749
1750
1751
1752 scsiback_drop_nexus(tpg);
1753
1754
1755
1756 core_tpg_deregister(se_tpg);
1757 kfree(tpg);
1758}
1759
1760static int scsiback_check_true(struct se_portal_group *se_tpg)
1761{
1762 return 1;
1763}
1764
1765static int scsiback_check_false(struct se_portal_group *se_tpg)
1766{
1767 return 0;
1768}
1769
1770static const struct target_core_fabric_ops scsiback_ops = {
1771 .module = THIS_MODULE,
1772 .fabric_name = "xen-pvscsi",
1773 .tpg_get_wwn = scsiback_get_fabric_wwn,
1774 .tpg_get_tag = scsiback_get_tag,
1775 .tpg_check_demo_mode = scsiback_check_true,
1776 .tpg_check_demo_mode_cache = scsiback_check_true,
1777 .tpg_check_demo_mode_write_protect = scsiback_check_false,
1778 .tpg_check_prod_mode_write_protect = scsiback_check_false,
1779 .tpg_get_inst_index = scsiback_tpg_get_inst_index,
1780 .check_stop_free = scsiback_check_stop_free,
1781 .release_cmd = scsiback_release_cmd,
1782 .sess_get_index = scsiback_sess_get_index,
1783 .sess_get_initiator_sid = NULL,
1784 .write_pending = scsiback_write_pending,
1785 .set_default_node_attributes = scsiback_set_default_node_attrs,
1786 .get_cmd_state = scsiback_get_cmd_state,
1787 .queue_data_in = scsiback_queue_data_in,
1788 .queue_status = scsiback_queue_status,
1789 .queue_tm_rsp = scsiback_queue_tm_rsp,
1790 .aborted_task = scsiback_aborted_task,
1791
1792
1793
1794 .fabric_make_wwn = scsiback_make_tport,
1795 .fabric_drop_wwn = scsiback_drop_tport,
1796 .fabric_make_tpg = scsiback_make_tpg,
1797 .fabric_drop_tpg = scsiback_drop_tpg,
1798 .fabric_post_link = scsiback_port_link,
1799 .fabric_pre_unlink = scsiback_port_unlink,
1800
1801 .tfc_wwn_attrs = scsiback_wwn_attrs,
1802 .tfc_tpg_base_attrs = scsiback_tpg_attrs,
1803 .tfc_tpg_param_attrs = scsiback_param_attrs,
1804};
1805
1806static const struct xenbus_device_id scsiback_ids[] = {
1807 { "vscsi" },
1808 { "" }
1809};
1810
1811static struct xenbus_driver scsiback_driver = {
1812 .ids = scsiback_ids,
1813 .probe = scsiback_probe,
1814 .remove = scsiback_remove,
1815 .otherend_changed = scsiback_frontend_changed
1816};
1817
1818static int __init scsiback_init(void)
1819{
1820 int ret;
1821
1822 if (!xen_domain())
1823 return -ENODEV;
1824
1825 pr_debug("xen-pvscsi: fabric module %s on %s/%s on "UTS_RELEASE"\n",
1826 VSCSI_VERSION, utsname()->sysname, utsname()->machine);
1827
1828 ret = xenbus_register_backend(&scsiback_driver);
1829 if (ret)
1830 goto out;
1831
1832 ret = target_register_template(&scsiback_ops);
1833 if (ret)
1834 goto out_unregister_xenbus;
1835
1836 return 0;
1837
1838out_unregister_xenbus:
1839 xenbus_unregister_driver(&scsiback_driver);
1840out:
1841 pr_err("%s: error %d\n", __func__, ret);
1842 return ret;
1843}
1844
1845static void __exit scsiback_exit(void)
1846{
1847 target_unregister_template(&scsiback_ops);
1848 xenbus_unregister_driver(&scsiback_driver);
1849}
1850
1851module_init(scsiback_init);
1852module_exit(scsiback_exit);
1853
1854MODULE_DESCRIPTION("Xen SCSI backend driver");
1855MODULE_LICENSE("Dual BSD/GPL");
1856MODULE_ALIAS("xen-backend:vscsi");
1857MODULE_AUTHOR("Juergen Gross <jgross@suse.com>");
1858
