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33
34#define pr_fmt(fmt) "xen-pvscsi: " fmt
35
36#include <linux/module.h>
37#include <linux/utsname.h>
38#include <linux/interrupt.h>
39#include <linux/slab.h>
40#include <linux/wait.h>
41#include <linux/sched.h>
42#include <linux/list.h>
43#include <linux/gfp.h>
44#include <linux/delay.h>
45#include <linux/spinlock.h>
46#include <linux/configfs.h>
47
48#include <generated/utsrelease.h>
49
50#include <scsi/scsi_host.h>
51
52#include <target/target_core_base.h>
53#include <target/target_core_fabric.h>
54
55#include <asm/hypervisor.h>
56
57#include <xen/xen.h>
58#include <xen/balloon.h>
59#include <xen/events.h>
60#include <xen/xenbus.h>
61#include <xen/grant_table.h>
62#include <xen/page.h>
63
64#include <xen/interface/grant_table.h>
65#include <xen/interface/io/vscsiif.h>
66
67#define VSCSI_VERSION "v0.1"
68#define VSCSI_NAMELEN 32
69
70struct ids_tuple {
71 unsigned int hst;
72 unsigned int chn;
73 unsigned int tgt;
74 unsigned int lun;
75};
76
77struct v2p_entry {
78 struct ids_tuple v;
79 struct scsiback_tpg *tpg;
80 unsigned int lun;
81 struct kref kref;
82 struct list_head l;
83};
84
85struct vscsibk_info {
86 struct xenbus_device *dev;
87
88 domid_t domid;
89 unsigned int irq;
90
91 struct vscsiif_back_ring ring;
92
93 spinlock_t ring_lock;
94 atomic_t nr_unreplied_reqs;
95
96 spinlock_t v2p_lock;
97 struct list_head v2p_entry_lists;
98
99 wait_queue_head_t waiting_to_free;
100
101 struct gnttab_page_cache free_pages;
102};
103
104
105#define VSCSI_MAX_GRANTS (SG_ALL + VSCSIIF_SG_TABLESIZE)
106
107
108
109
110
111
112#define VSCSI_GRANT_BATCH 16
113
114struct vscsibk_pend {
115 uint16_t rqid;
116
117 uint8_t cmnd[VSCSIIF_MAX_COMMAND_SIZE];
118 uint8_t cmd_len;
119
120 uint8_t sc_data_direction;
121 uint16_t n_sg;
122 uint16_t n_grants;
123 uint32_t data_len;
124 uint32_t result;
125
126 struct vscsibk_info *info;
127 struct v2p_entry *v2p;
128 struct scatterlist *sgl;
129
130 uint8_t sense_buffer[VSCSIIF_SENSE_BUFFERSIZE];
131
132 grant_handle_t grant_handles[VSCSI_MAX_GRANTS];
133 struct page *pages[VSCSI_MAX_GRANTS];
134
135 struct se_cmd se_cmd;
136
137 struct completion tmr_done;
138};
139
140#define VSCSI_DEFAULT_SESSION_TAGS 128
141
142struct scsiback_nexus {
143
144 struct se_session *tvn_se_sess;
145};
146
147struct scsiback_tport {
148
149 u8 tport_proto_id;
150
151 u64 tport_wwpn;
152
153 char tport_name[VSCSI_NAMELEN];
154
155 struct se_wwn tport_wwn;
156};
157
158struct scsiback_tpg {
159
160 u16 tport_tpgt;
161
162 int tv_tpg_port_count;
163
164 int tv_tpg_fe_count;
165
166 struct list_head tv_tpg_list;
167
168 struct mutex tv_tpg_mutex;
169
170 struct scsiback_nexus *tpg_nexus;
171
172 struct scsiback_tport *tport;
173
174 struct se_portal_group se_tpg;
175
176 char param_alias[VSCSI_NAMELEN];
177
178 struct list_head info_list;
179};
180
181#define SCSIBACK_INVALID_HANDLE (~0)
182
183static bool log_print_stat;
184module_param(log_print_stat, bool, 0644);
185
186static int scsiback_max_buffer_pages = 1024;
187module_param_named(max_buffer_pages, scsiback_max_buffer_pages, int, 0644);
188MODULE_PARM_DESC(max_buffer_pages,
189"Maximum number of free pages to keep in backend buffer");
190
191
192static DEFINE_MUTEX(scsiback_mutex);
193static LIST_HEAD(scsiback_list);
194
195static void scsiback_get(struct vscsibk_info *info)
196{
197 atomic_inc(&info->nr_unreplied_reqs);
198}
199
200static void scsiback_put(struct vscsibk_info *info)
201{
202 if (atomic_dec_and_test(&info->nr_unreplied_reqs))
203 wake_up(&info->waiting_to_free);
204}
205
206static unsigned long vaddr_page(struct page *page)
207{
208 unsigned long pfn = page_to_pfn(page);
209
210 return (unsigned long)pfn_to_kaddr(pfn);
211}
212
213static unsigned long vaddr(struct vscsibk_pend *req, int seg)
214{
215 return vaddr_page(req->pages[seg]);
216}
217
218static void scsiback_print_status(char *sense_buffer, int errors,
219 struct vscsibk_pend *pending_req)
220{
221 struct scsiback_tpg *tpg = pending_req->v2p->tpg;
222
223 pr_err("[%s:%d] cmnd[0]=%02x -> st=%02x msg=%02x host=%02x\n",
224 tpg->tport->tport_name, pending_req->v2p->lun,
225 pending_req->cmnd[0], errors & 0xff, COMMAND_COMPLETE,
226 host_byte(errors));
227}
228
229static void scsiback_fast_flush_area(struct vscsibk_pend *req)
230{
231 struct gnttab_unmap_grant_ref unmap[VSCSI_GRANT_BATCH];
232 struct page *pages[VSCSI_GRANT_BATCH];
233 unsigned int i, invcount = 0;
234 grant_handle_t handle;
235 int err;
236
237 kfree(req->sgl);
238 req->sgl = NULL;
239 req->n_sg = 0;
240
241 if (!req->n_grants)
242 return;
243
244 for (i = 0; i < req->n_grants; i++) {
245 handle = req->grant_handles[i];
246 if (handle == SCSIBACK_INVALID_HANDLE)
247 continue;
248 gnttab_set_unmap_op(&unmap[invcount], vaddr(req, i),
249 GNTMAP_host_map, handle);
250 req->grant_handles[i] = SCSIBACK_INVALID_HANDLE;
251 pages[invcount] = req->pages[i];
252 put_page(pages[invcount]);
253 invcount++;
254 if (invcount < VSCSI_GRANT_BATCH)
255 continue;
256 err = gnttab_unmap_refs(unmap, NULL, pages, invcount);
257 BUG_ON(err);
258 invcount = 0;
259 }
260
261 if (invcount) {
262 err = gnttab_unmap_refs(unmap, NULL, pages, invcount);
263 BUG_ON(err);
264 }
265
266 gnttab_page_cache_put(&req->info->free_pages, req->pages,
267 req->n_grants);
268 req->n_grants = 0;
269}
270
271static void scsiback_free_translation_entry(struct kref *kref)
272{
273 struct v2p_entry *entry = container_of(kref, struct v2p_entry, kref);
274 struct scsiback_tpg *tpg = entry->tpg;
275
276 mutex_lock(&tpg->tv_tpg_mutex);
277 tpg->tv_tpg_fe_count--;
278 mutex_unlock(&tpg->tv_tpg_mutex);
279
280 kfree(entry);
281}
282
283static void scsiback_send_response(struct vscsibk_info *info,
284 char *sense_buffer, int32_t result, uint32_t resid,
285 uint16_t rqid)
286{
287 struct vscsiif_response *ring_res;
288 int notify;
289 struct scsi_sense_hdr sshdr;
290 unsigned long flags;
291 unsigned len;
292
293 spin_lock_irqsave(&info->ring_lock, flags);
294
295 ring_res = RING_GET_RESPONSE(&info->ring, info->ring.rsp_prod_pvt);
296 info->ring.rsp_prod_pvt++;
297
298 ring_res->rslt = result;
299 ring_res->rqid = rqid;
300
301 if (sense_buffer != NULL &&
302 scsi_normalize_sense(sense_buffer, VSCSIIF_SENSE_BUFFERSIZE,
303 &sshdr)) {
304 len = min_t(unsigned, 8 + sense_buffer[7],
305 VSCSIIF_SENSE_BUFFERSIZE);
306 memcpy(ring_res->sense_buffer, sense_buffer, len);
307 ring_res->sense_len = len;
308 } else {
309 ring_res->sense_len = 0;
310 }
311
312 ring_res->residual_len = resid;
313
314 RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&info->ring, notify);
315 spin_unlock_irqrestore(&info->ring_lock, flags);
316
317 if (notify)
318 notify_remote_via_irq(info->irq);
319}
320
321static void scsiback_do_resp_with_sense(char *sense_buffer, int32_t result,
322 uint32_t resid, struct vscsibk_pend *pending_req)
323{
324 scsiback_send_response(pending_req->info, sense_buffer, result,
325 resid, pending_req->rqid);
326
327 if (pending_req->v2p)
328 kref_put(&pending_req->v2p->kref,
329 scsiback_free_translation_entry);
330}
331
332static void scsiback_cmd_done(struct vscsibk_pend *pending_req)
333{
334 struct vscsibk_info *info = pending_req->info;
335 unsigned char *sense_buffer;
336 unsigned int resid;
337 int errors;
338
339 sense_buffer = pending_req->sense_buffer;
340 resid = pending_req->se_cmd.residual_count;
341 errors = pending_req->result;
342
343 if (errors && log_print_stat)
344 scsiback_print_status(sense_buffer, errors, pending_req);
345
346 scsiback_fast_flush_area(pending_req);
347 scsiback_do_resp_with_sense(sense_buffer, errors, resid, pending_req);
348 scsiback_put(info);
349
350
351
352
353
354 target_put_sess_cmd(&pending_req->se_cmd);
355}
356
357static void scsiback_cmd_exec(struct vscsibk_pend *pending_req)
358{
359 struct se_cmd *se_cmd = &pending_req->se_cmd;
360 struct se_session *sess = pending_req->v2p->tpg->tpg_nexus->tvn_se_sess;
361
362 scsiback_get(pending_req->info);
363 se_cmd->tag = pending_req->rqid;
364 target_init_cmd(se_cmd, sess, pending_req->sense_buffer,
365 pending_req->v2p->lun, pending_req->data_len, 0,
366 pending_req->sc_data_direction, TARGET_SCF_ACK_KREF);
367
368 if (target_submit_prep(se_cmd, pending_req->cmnd, pending_req->sgl,
369 pending_req->n_sg, NULL, 0, NULL, 0, GFP_KERNEL))
370 return;
371
372 target_submit(se_cmd);
373}
374
375static int scsiback_gnttab_data_map_batch(struct gnttab_map_grant_ref *map,
376 struct page **pg, grant_handle_t *grant, int cnt)
377{
378 int err, i;
379
380 if (!cnt)
381 return 0;
382
383 err = gnttab_map_refs(map, NULL, pg, cnt);
384 for (i = 0; i < cnt; i++) {
385 if (unlikely(map[i].status != GNTST_okay)) {
386 pr_err("invalid buffer -- could not remap it\n");
387 map[i].handle = SCSIBACK_INVALID_HANDLE;
388 if (!err)
389 err = -ENOMEM;
390 } else {
391 get_page(pg[i]);
392 }
393 grant[i] = map[i].handle;
394 }
395 return err;
396}
397
398static int scsiback_gnttab_data_map_list(struct vscsibk_pend *pending_req,
399 struct scsiif_request_segment *seg, struct page **pg,
400 grant_handle_t *grant, int cnt, u32 flags)
401{
402 int mapcount = 0, i, err = 0;
403 struct gnttab_map_grant_ref map[VSCSI_GRANT_BATCH];
404 struct vscsibk_info *info = pending_req->info;
405
406 for (i = 0; i < cnt; i++) {
407 if (gnttab_page_cache_get(&info->free_pages, pg + mapcount)) {
408 gnttab_page_cache_put(&info->free_pages, pg, mapcount);
409 pr_err("no grant page\n");
410 return -ENOMEM;
411 }
412 gnttab_set_map_op(&map[mapcount], vaddr_page(pg[mapcount]),
413 flags, seg[i].gref, info->domid);
414 mapcount++;
415 if (mapcount < VSCSI_GRANT_BATCH)
416 continue;
417 err = scsiback_gnttab_data_map_batch(map, pg, grant, mapcount);
418 pg += mapcount;
419 grant += mapcount;
420 pending_req->n_grants += mapcount;
421 if (err)
422 return err;
423 mapcount = 0;
424 }
425 err = scsiback_gnttab_data_map_batch(map, pg, grant, mapcount);
426 pending_req->n_grants += mapcount;
427 return err;
428}
429
430static int scsiback_gnttab_data_map(struct vscsiif_request *ring_req,
431 struct vscsibk_pend *pending_req)
432{
433 u32 flags;
434 int i, err, n_segs, i_seg = 0;
435 struct page **pg;
436 struct scsiif_request_segment *seg;
437 unsigned long end_seg = 0;
438 unsigned int nr_segments = (unsigned int)ring_req->nr_segments;
439 unsigned int nr_sgl = 0;
440 struct scatterlist *sg;
441 grant_handle_t *grant;
442
443 pending_req->n_sg = 0;
444 pending_req->n_grants = 0;
445 pending_req->data_len = 0;
446
447 nr_segments &= ~VSCSIIF_SG_GRANT;
448 if (!nr_segments)
449 return 0;
450
451 if (nr_segments > VSCSIIF_SG_TABLESIZE) {
452 pr_debug("invalid parameter nr_seg = %d\n",
453 ring_req->nr_segments);
454 return -EINVAL;
455 }
456
457 if (ring_req->nr_segments & VSCSIIF_SG_GRANT) {
458 err = scsiback_gnttab_data_map_list(pending_req, ring_req->seg,
459 pending_req->pages, pending_req->grant_handles,
460 nr_segments, GNTMAP_host_map | GNTMAP_readonly);
461 if (err)
462 return err;
463 nr_sgl = nr_segments;
464 nr_segments = 0;
465 for (i = 0; i < nr_sgl; i++) {
466 n_segs = ring_req->seg[i].length /
467 sizeof(struct scsiif_request_segment);
468 if ((unsigned)ring_req->seg[i].offset +
469 (unsigned)ring_req->seg[i].length > PAGE_SIZE ||
470 n_segs * sizeof(struct scsiif_request_segment) !=
471 ring_req->seg[i].length)
472 return -EINVAL;
473 nr_segments += n_segs;
474 }
475 if (nr_segments > SG_ALL) {
476 pr_debug("invalid nr_seg = %d\n", nr_segments);
477 return -EINVAL;
478 }
479 }
480
481
482 pending_req->sgl = kmalloc_array(nr_segments,
483 sizeof(struct scatterlist), GFP_KERNEL);
484 if (!pending_req->sgl)
485 return -ENOMEM;
486
487 sg_init_table(pending_req->sgl, nr_segments);
488 pending_req->n_sg = nr_segments;
489
490 flags = GNTMAP_host_map;
491 if (pending_req->sc_data_direction == DMA_TO_DEVICE)
492 flags |= GNTMAP_readonly;
493
494 pg = pending_req->pages + nr_sgl;
495 grant = pending_req->grant_handles + nr_sgl;
496 if (!nr_sgl) {
497 seg = ring_req->seg;
498 err = scsiback_gnttab_data_map_list(pending_req, seg,
499 pg, grant, nr_segments, flags);
500 if (err)
501 return err;
502 } else {
503 for (i = 0; i < nr_sgl; i++) {
504 seg = (struct scsiif_request_segment *)(
505 vaddr(pending_req, i) + ring_req->seg[i].offset);
506 n_segs = ring_req->seg[i].length /
507 sizeof(struct scsiif_request_segment);
508 err = scsiback_gnttab_data_map_list(pending_req, seg,
509 pg, grant, n_segs, flags);
510 if (err)
511 return err;
512 pg += n_segs;
513 grant += n_segs;
514 }
515 end_seg = vaddr(pending_req, 0) + ring_req->seg[0].offset;
516 seg = (struct scsiif_request_segment *)end_seg;
517 end_seg += ring_req->seg[0].length;
518 pg = pending_req->pages + nr_sgl;
519 }
520
521 for_each_sg(pending_req->sgl, sg, nr_segments, i) {
522 sg_set_page(sg, pg[i], seg->length, seg->offset);
523 pending_req->data_len += seg->length;
524 seg++;
525 if (nr_sgl && (unsigned long)seg >= end_seg) {
526 i_seg++;
527 end_seg = vaddr(pending_req, i_seg) +
528 ring_req->seg[i_seg].offset;
529 seg = (struct scsiif_request_segment *)end_seg;
530 end_seg += ring_req->seg[i_seg].length;
531 }
532 if (sg->offset >= PAGE_SIZE ||
533 sg->length > PAGE_SIZE ||
534 sg->offset + sg->length > PAGE_SIZE)
535 return -EINVAL;
536 }
537
538 return 0;
539}
540
541static void scsiback_disconnect(struct vscsibk_info *info)
542{
543 wait_event(info->waiting_to_free,
544 atomic_read(&info->nr_unreplied_reqs) == 0);
545
546 unbind_from_irqhandler(info->irq, info);
547 info->irq = 0;
548 xenbus_unmap_ring_vfree(info->dev, info->ring.sring);
549}
550
551static void scsiback_device_action(struct vscsibk_pend *pending_req,
552 enum tcm_tmreq_table act, int tag)
553{
554 struct scsiback_tpg *tpg = pending_req->v2p->tpg;
555 struct scsiback_nexus *nexus = tpg->tpg_nexus;
556 struct se_cmd *se_cmd = &pending_req->se_cmd;
557 u64 unpacked_lun = pending_req->v2p->lun;
558 int rc, err = FAILED;
559
560 init_completion(&pending_req->tmr_done);
561
562 rc = target_submit_tmr(&pending_req->se_cmd, nexus->tvn_se_sess,
563 &pending_req->sense_buffer[0],
564 unpacked_lun, NULL, act, GFP_KERNEL,
565 tag, TARGET_SCF_ACK_KREF);
566 if (rc)
567 goto err;
568
569 wait_for_completion(&pending_req->tmr_done);
570
571 err = (se_cmd->se_tmr_req->response == TMR_FUNCTION_COMPLETE) ?
572 SUCCESS : FAILED;
573
574 scsiback_do_resp_with_sense(NULL, err, 0, pending_req);
575 transport_generic_free_cmd(&pending_req->se_cmd, 0);
576 return;
577
578err:
579 scsiback_do_resp_with_sense(NULL, err, 0, pending_req);
580}
581
582
583
584
585static struct v2p_entry *scsiback_do_translation(struct vscsibk_info *info,
586 struct ids_tuple *v)
587{
588 struct v2p_entry *entry;
589 struct list_head *head = &(info->v2p_entry_lists);
590 unsigned long flags;
591
592 spin_lock_irqsave(&info->v2p_lock, flags);
593 list_for_each_entry(entry, head, l) {
594 if ((entry->v.chn == v->chn) &&
595 (entry->v.tgt == v->tgt) &&
596 (entry->v.lun == v->lun)) {
597 kref_get(&entry->kref);
598 goto out;
599 }
600 }
601 entry = NULL;
602
603out:
604 spin_unlock_irqrestore(&info->v2p_lock, flags);
605 return entry;
606}
607
608static struct vscsibk_pend *scsiback_get_pend_req(struct vscsiif_back_ring *ring,
609 struct v2p_entry *v2p)
610{
611 struct scsiback_tpg *tpg = v2p->tpg;
612 struct scsiback_nexus *nexus = tpg->tpg_nexus;
613 struct se_session *se_sess = nexus->tvn_se_sess;
614 struct vscsibk_pend *req;
615 int tag, cpu, i;
616
617 tag = sbitmap_queue_get(&se_sess->sess_tag_pool, &cpu);
618 if (tag < 0) {
619 pr_err("Unable to obtain tag for vscsiif_request\n");
620 return ERR_PTR(-ENOMEM);
621 }
622
623 req = &((struct vscsibk_pend *)se_sess->sess_cmd_map)[tag];
624 memset(req, 0, sizeof(*req));
625 req->se_cmd.map_tag = tag;
626 req->se_cmd.map_cpu = cpu;
627
628 for (i = 0; i < VSCSI_MAX_GRANTS; i++)
629 req->grant_handles[i] = SCSIBACK_INVALID_HANDLE;
630
631 return req;
632}
633
634static struct vscsibk_pend *prepare_pending_reqs(struct vscsibk_info *info,
635 struct vscsiif_back_ring *ring,
636 struct vscsiif_request *ring_req)
637{
638 struct vscsibk_pend *pending_req;
639 struct v2p_entry *v2p;
640 struct ids_tuple vir;
641
642
643 if ((ring_req->sc_data_direction != DMA_BIDIRECTIONAL) &&
644 (ring_req->sc_data_direction != DMA_TO_DEVICE) &&
645 (ring_req->sc_data_direction != DMA_FROM_DEVICE) &&
646 (ring_req->sc_data_direction != DMA_NONE)) {
647 pr_debug("invalid parameter data_dir = %d\n",
648 ring_req->sc_data_direction);
649 return ERR_PTR(-EINVAL);
650 }
651 if (ring_req->cmd_len > VSCSIIF_MAX_COMMAND_SIZE) {
652 pr_debug("invalid parameter cmd_len = %d\n",
653 ring_req->cmd_len);
654 return ERR_PTR(-EINVAL);
655 }
656
657 vir.chn = ring_req->channel;
658 vir.tgt = ring_req->id;
659 vir.lun = ring_req->lun;
660
661 v2p = scsiback_do_translation(info, &vir);
662 if (!v2p) {
663 pr_debug("the v2p of (chn:%d, tgt:%d, lun:%d) doesn't exist.\n",
664 vir.chn, vir.tgt, vir.lun);
665 return ERR_PTR(-ENODEV);
666 }
667
668 pending_req = scsiback_get_pend_req(ring, v2p);
669 if (IS_ERR(pending_req)) {
670 kref_put(&v2p->kref, scsiback_free_translation_entry);
671 return ERR_PTR(-ENOMEM);
672 }
673 pending_req->rqid = ring_req->rqid;
674 pending_req->info = info;
675 pending_req->v2p = v2p;
676 pending_req->sc_data_direction = ring_req->sc_data_direction;
677 pending_req->cmd_len = ring_req->cmd_len;
678 memcpy(pending_req->cmnd, ring_req->cmnd, pending_req->cmd_len);
679
680 return pending_req;
681}
682
683static int scsiback_do_cmd_fn(struct vscsibk_info *info,
684 unsigned int *eoi_flags)
685{
686 struct vscsiif_back_ring *ring = &info->ring;
687 struct vscsiif_request ring_req;
688 struct vscsibk_pend *pending_req;
689 RING_IDX rc, rp;
690 int more_to_do;
691 uint32_t result;
692
693 rc = ring->req_cons;
694 rp = ring->sring->req_prod;
695 rmb();
696
697 if (RING_REQUEST_PROD_OVERFLOW(ring, rp)) {
698 rc = ring->rsp_prod_pvt;
699 pr_warn("Dom%d provided bogus ring requests (%#x - %#x = %u). Halting ring processing\n",
700 info->domid, rp, rc, rp - rc);
701 return -EINVAL;
702 }
703
704 while ((rc != rp)) {
705 *eoi_flags &= ~XEN_EOI_FLAG_SPURIOUS;
706
707 if (RING_REQUEST_CONS_OVERFLOW(ring, rc))
708 break;
709
710 RING_COPY_REQUEST(ring, rc, &ring_req);
711 ring->req_cons = ++rc;
712
713 pending_req = prepare_pending_reqs(info, ring, &ring_req);
714 if (IS_ERR(pending_req)) {
715 switch (PTR_ERR(pending_req)) {
716 case -ENODEV:
717 result = DID_NO_CONNECT;
718 break;
719 default:
720 result = DID_ERROR;
721 break;
722 }
723 scsiback_send_response(info, NULL, result << 16, 0,
724 ring_req.rqid);
725 return 1;
726 }
727
728 switch (ring_req.act) {
729 case VSCSIIF_ACT_SCSI_CDB:
730 if (scsiback_gnttab_data_map(&ring_req, pending_req)) {
731 scsiback_fast_flush_area(pending_req);
732 scsiback_do_resp_with_sense(NULL,
733 DID_ERROR << 16, 0, pending_req);
734 transport_generic_free_cmd(&pending_req->se_cmd, 0);
735 } else {
736 scsiback_cmd_exec(pending_req);
737 }
738 break;
739 case VSCSIIF_ACT_SCSI_ABORT:
740 scsiback_device_action(pending_req, TMR_ABORT_TASK,
741 ring_req.ref_rqid);
742 break;
743 case VSCSIIF_ACT_SCSI_RESET:
744 scsiback_device_action(pending_req, TMR_LUN_RESET, 0);
745 break;
746 default:
747 pr_err_ratelimited("invalid request\n");
748 scsiback_do_resp_with_sense(NULL, DID_ERROR << 16, 0,
749 pending_req);
750 transport_generic_free_cmd(&pending_req->se_cmd, 0);
751 break;
752 }
753
754
755 cond_resched();
756 }
757
758 gnttab_page_cache_shrink(&info->free_pages, scsiback_max_buffer_pages);
759
760 RING_FINAL_CHECK_FOR_REQUESTS(&info->ring, more_to_do);
761 return more_to_do;
762}
763
764static irqreturn_t scsiback_irq_fn(int irq, void *dev_id)
765{
766 struct vscsibk_info *info = dev_id;
767 int rc;
768 unsigned int eoi_flags = XEN_EOI_FLAG_SPURIOUS;
769
770 while ((rc = scsiback_do_cmd_fn(info, &eoi_flags)) > 0)
771 cond_resched();
772
773
774 if (!rc)
775 xen_irq_lateeoi(irq, eoi_flags);
776
777 return IRQ_HANDLED;
778}
779
780static int scsiback_init_sring(struct vscsibk_info *info, grant_ref_t ring_ref,
781 evtchn_port_t evtchn)
782{
783 void *area;
784 struct vscsiif_sring *sring;
785 int err;
786
787 if (info->irq)
788 return -1;
789
790 err = xenbus_map_ring_valloc(info->dev, &ring_ref, 1, &area);
791 if (err)
792 return err;
793
794 sring = (struct vscsiif_sring *)area;
795 BACK_RING_INIT(&info->ring, sring, PAGE_SIZE);
796
797 err = bind_interdomain_evtchn_to_irq_lateeoi(info->dev, evtchn);
798 if (err < 0)
799 goto unmap_page;
800
801 info->irq = err;
802
803 err = request_threaded_irq(info->irq, NULL, scsiback_irq_fn,
804 IRQF_ONESHOT, "vscsiif-backend", info);
805 if (err)
806 goto free_irq;
807
808 return 0;
809
810free_irq:
811 unbind_from_irqhandler(info->irq, info);
812 info->irq = 0;
813unmap_page:
814 xenbus_unmap_ring_vfree(info->dev, area);
815
816 return err;
817}
818
819static int scsiback_map(struct vscsibk_info *info)
820{
821 struct xenbus_device *dev = info->dev;
822 unsigned int ring_ref;
823 evtchn_port_t evtchn;
824 int err;
825
826 err = xenbus_gather(XBT_NIL, dev->otherend,
827 "ring-ref", "%u", &ring_ref,
828 "event-channel", "%u", &evtchn, NULL);
829 if (err) {
830 xenbus_dev_fatal(dev, err, "reading %s ring", dev->otherend);
831 return err;
832 }
833
834 return scsiback_init_sring(info, ring_ref, evtchn);
835}
836
837
838
839
840static struct v2p_entry *scsiback_chk_translation_entry(
841 struct vscsibk_info *info, struct ids_tuple *v)
842{
843 struct list_head *head = &(info->v2p_entry_lists);
844 struct v2p_entry *entry;
845
846 list_for_each_entry(entry, head, l)
847 if ((entry->v.chn == v->chn) &&
848 (entry->v.tgt == v->tgt) &&
849 (entry->v.lun == v->lun))
850 return entry;
851
852 return NULL;
853}
854
855
856
857
858static int scsiback_add_translation_entry(struct vscsibk_info *info,
859 char *phy, struct ids_tuple *v)
860{
861 int err = 0;
862 struct v2p_entry *new;
863 unsigned long flags;
864 char *lunp;
865 unsigned long long unpacked_lun;
866 struct se_lun *se_lun;
867 struct scsiback_tpg *tpg_entry, *tpg = NULL;
868 char *error = "doesn't exist";
869
870 lunp = strrchr(phy, ':');
871 if (!lunp) {
872 pr_err("illegal format of physical device %s\n", phy);
873 return -EINVAL;
874 }
875 *lunp = 0;
876 lunp++;
877 err = kstrtoull(lunp, 10, &unpacked_lun);
878 if (err < 0) {
879 pr_err("lun number not valid: %s\n", lunp);
880 return err;
881 }
882
883 mutex_lock(&scsiback_mutex);
884 list_for_each_entry(tpg_entry, &scsiback_list, tv_tpg_list) {
885 if (!strcmp(phy, tpg_entry->tport->tport_name) ||
886 !strcmp(phy, tpg_entry->param_alias)) {
887 mutex_lock(&tpg_entry->se_tpg.tpg_lun_mutex);
888 hlist_for_each_entry(se_lun, &tpg_entry->se_tpg.tpg_lun_hlist, link) {
889 if (se_lun->unpacked_lun == unpacked_lun) {
890 if (!tpg_entry->tpg_nexus)
891 error = "nexus undefined";
892 else
893 tpg = tpg_entry;
894 break;
895 }
896 }
897 mutex_unlock(&tpg_entry->se_tpg.tpg_lun_mutex);
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:%llu %s\n", phy, unpacked_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
922 if (scsiback_chk_translation_entry(info, v)) {
923 pr_warn("Virtual ID is already used. Assignment was not performed.\n");
924 err = -EEXIST;
925 goto out;
926 }
927
928
929 kref_init(&new->kref);
930 new->v = *v;
931 new->tpg = tpg;
932 new->lun = unpacked_lun;
933 list_add_tail(&new->l, &info->v2p_entry_lists);
934
935out:
936 spin_unlock_irqrestore(&info->v2p_lock, flags);
937
938out_free:
939 if (err) {
940 mutex_lock(&tpg->tv_tpg_mutex);
941 tpg->tv_tpg_fe_count--;
942 mutex_unlock(&tpg->tv_tpg_mutex);
943 kfree(new);
944 }
945
946 return err;
947}
948
949static void __scsiback_del_translation_entry(struct v2p_entry *entry)
950{
951 list_del(&entry->l);
952 kref_put(&entry->kref, scsiback_free_translation_entry);
953}
954
955
956
957
958static int scsiback_del_translation_entry(struct vscsibk_info *info,
959 struct ids_tuple *v)
960{
961 struct v2p_entry *entry;
962 unsigned long flags;
963 int ret = 0;
964
965 spin_lock_irqsave(&info->v2p_lock, flags);
966
967 entry = scsiback_chk_translation_entry(info, v);
968 if (entry)
969 __scsiback_del_translation_entry(entry);
970 else
971 ret = -ENOENT;
972
973 spin_unlock_irqrestore(&info->v2p_lock, flags);
974 return ret;
975}
976
977static void scsiback_do_add_lun(struct vscsibk_info *info, const char *state,
978 char *phy, struct ids_tuple *vir, int try)
979{
980 struct v2p_entry *entry;
981 unsigned long flags;
982 int err;
983
984 if (try) {
985 spin_lock_irqsave(&info->v2p_lock, flags);
986 entry = scsiback_chk_translation_entry(info, vir);
987 spin_unlock_irqrestore(&info->v2p_lock, flags);
988 if (entry)
989 return;
990 }
991 if (!scsiback_add_translation_entry(info, phy, vir)) {
992 if (xenbus_printf(XBT_NIL, info->dev->nodename, state,
993 "%d", XenbusStateInitialised)) {
994 pr_err("xenbus_printf error %s\n", state);
995 scsiback_del_translation_entry(info, vir);
996 }
997 } else if (!try) {
998 err = xenbus_printf(XBT_NIL, info->dev->nodename, state,
999 "%d", XenbusStateClosed);
1000 if (err)
1001 xenbus_dev_error(info->dev, err,
1002 "%s: writing %s", __func__, state);
1003 }
1004}
1005
1006static 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
1019static 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
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
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 err = xenbus_printf(XBT_NIL, dev->nodename, state,
1042 "%d", XenbusStateClosed);
1043 if (err)
1044 xenbus_dev_error(info->dev, err,
1045 "%s: writing %s", __func__, state);
1046 return;
1047 }
1048 strlcpy(phy, val, VSCSI_NAMELEN);
1049 kfree(val);
1050
1051
1052 snprintf(str, sizeof(str), "vscsi-devs/%s/v-dev", ent);
1053 err = xenbus_scanf(XBT_NIL, dev->nodename, str, "%u:%u:%u:%u",
1054 &vir.hst, &vir.chn, &vir.tgt, &vir.lun);
1055 if (XENBUS_EXIST_ERR(err)) {
1056 err = xenbus_printf(XBT_NIL, dev->nodename, state,
1057 "%d", XenbusStateClosed);
1058 if (err)
1059 xenbus_dev_error(info->dev, err,
1060 "%s: writing %s", __func__, state);
1061 return;
1062 }
1063
1064 switch (op) {
1065 case VSCSIBACK_OP_ADD_OR_DEL_LUN:
1066 switch (device_state) {
1067 case XenbusStateInitialising:
1068 scsiback_do_add_lun(info, state, phy, &vir, 0);
1069 break;
1070 case XenbusStateConnected:
1071 scsiback_do_add_lun(info, state, phy, &vir, 1);
1072 break;
1073 case XenbusStateClosing:
1074 scsiback_do_del_lun(info, state, &vir);
1075 break;
1076 default:
1077 break;
1078 }
1079 break;
1080
1081 case VSCSIBACK_OP_UPDATEDEV_STATE:
1082 if (device_state == XenbusStateInitialised) {
1083
1084 if (xenbus_printf(XBT_NIL, dev->nodename, state,
1085 "%d", XenbusStateConnected)) {
1086 pr_err("xenbus_printf error %s\n", str);
1087 scsiback_del_translation_entry(info, &vir);
1088 xenbus_printf(XBT_NIL, dev->nodename, state,
1089 "%d", XenbusStateClosed);
1090 }
1091 }
1092 break;
1093
1094 default:
1095 break;
1096 }
1097}
1098
1099static void scsiback_do_lun_hotplug(struct vscsibk_info *info, int op)
1100{
1101 int i;
1102 char **dir;
1103 unsigned int ndir = 0;
1104
1105 dir = xenbus_directory(XBT_NIL, info->dev->nodename, "vscsi-devs",
1106 &ndir);
1107 if (IS_ERR(dir))
1108 return;
1109
1110 for (i = 0; i < ndir; i++)
1111 scsiback_do_1lun_hotplug(info, op, dir[i]);
1112
1113 kfree(dir);
1114}
1115
1116static void scsiback_frontend_changed(struct xenbus_device *dev,
1117 enum xenbus_state frontend_state)
1118{
1119 struct vscsibk_info *info = dev_get_drvdata(&dev->dev);
1120
1121 switch (frontend_state) {
1122 case XenbusStateInitialising:
1123 break;
1124
1125 case XenbusStateInitialised:
1126 if (scsiback_map(info))
1127 break;
1128
1129 scsiback_do_lun_hotplug(info, VSCSIBACK_OP_ADD_OR_DEL_LUN);
1130 xenbus_switch_state(dev, XenbusStateConnected);
1131 break;
1132
1133 case XenbusStateConnected:
1134 scsiback_do_lun_hotplug(info, VSCSIBACK_OP_UPDATEDEV_STATE);
1135
1136 if (dev->state == XenbusStateConnected)
1137 break;
1138
1139 xenbus_switch_state(dev, XenbusStateConnected);
1140 break;
1141
1142 case XenbusStateClosing:
1143 if (info->irq)
1144 scsiback_disconnect(info);
1145
1146 xenbus_switch_state(dev, XenbusStateClosing);
1147 break;
1148
1149 case XenbusStateClosed:
1150 xenbus_switch_state(dev, XenbusStateClosed);
1151 if (xenbus_dev_is_online(dev))
1152 break;
1153 fallthrough;
1154 case XenbusStateUnknown:
1155 device_unregister(&dev->dev);
1156 break;
1157
1158 case XenbusStateReconfiguring:
1159 scsiback_do_lun_hotplug(info, VSCSIBACK_OP_ADD_OR_DEL_LUN);
1160 xenbus_switch_state(dev, XenbusStateReconfigured);
1161
1162 break;
1163
1164 default:
1165 xenbus_dev_fatal(dev, -EINVAL, "saw state %d at frontend",
1166 frontend_state);
1167 break;
1168 }
1169}
1170
1171
1172
1173
1174static void scsiback_release_translation_entry(struct vscsibk_info *info)
1175{
1176 struct v2p_entry *entry, *tmp;
1177 struct list_head *head = &(info->v2p_entry_lists);
1178 unsigned long flags;
1179
1180 spin_lock_irqsave(&info->v2p_lock, flags);
1181
1182 list_for_each_entry_safe(entry, tmp, head, l)
1183 __scsiback_del_translation_entry(entry);
1184
1185 spin_unlock_irqrestore(&info->v2p_lock, flags);
1186}
1187
1188static int scsiback_remove(struct xenbus_device *dev)
1189{
1190 struct vscsibk_info *info = dev_get_drvdata(&dev->dev);
1191
1192 if (info->irq)
1193 scsiback_disconnect(info);
1194
1195 scsiback_release_translation_entry(info);
1196
1197 gnttab_page_cache_shrink(&info->free_pages, 0);
1198
1199 dev_set_drvdata(&dev->dev, NULL);
1200
1201 return 0;
1202}
1203
1204static int scsiback_probe(struct xenbus_device *dev,
1205 const struct xenbus_device_id *id)
1206{
1207 int err;
1208
1209 struct vscsibk_info *info = kzalloc(sizeof(struct vscsibk_info),
1210 GFP_KERNEL);
1211
1212 pr_debug("%s %p %d\n", __func__, dev, dev->otherend_id);
1213
1214 if (!info) {
1215 xenbus_dev_fatal(dev, -ENOMEM, "allocating backend structure");
1216 return -ENOMEM;
1217 }
1218 info->dev = dev;
1219 dev_set_drvdata(&dev->dev, info);
1220
1221 info->domid = dev->otherend_id;
1222 spin_lock_init(&info->ring_lock);
1223 atomic_set(&info->nr_unreplied_reqs, 0);
1224 init_waitqueue_head(&info->waiting_to_free);
1225 info->dev = dev;
1226 info->irq = 0;
1227 INIT_LIST_HEAD(&info->v2p_entry_lists);
1228 spin_lock_init(&info->v2p_lock);
1229 gnttab_page_cache_init(&info->free_pages);
1230
1231 err = xenbus_printf(XBT_NIL, dev->nodename, "feature-sg-grant", "%u",
1232 SG_ALL);
1233 if (err)
1234 xenbus_dev_error(dev, err, "writing feature-sg-grant");
1235
1236 err = xenbus_switch_state(dev, XenbusStateInitWait);
1237 if (err)
1238 goto fail;
1239
1240 return 0;
1241
1242fail:
1243 pr_warn("%s failed\n", __func__);
1244 scsiback_remove(dev);
1245
1246 return err;
1247}
1248
1249static char *scsiback_dump_proto_id(struct scsiback_tport *tport)
1250{
1251 switch (tport->tport_proto_id) {
1252 case SCSI_PROTOCOL_SAS:
1253 return "SAS";
1254 case SCSI_PROTOCOL_FCP:
1255 return "FCP";
1256 case SCSI_PROTOCOL_ISCSI:
1257 return "iSCSI";
1258 default:
1259 break;
1260 }
1261
1262 return "Unknown";
1263}
1264
1265static char *scsiback_get_fabric_wwn(struct se_portal_group *se_tpg)
1266{
1267 struct scsiback_tpg *tpg = container_of(se_tpg,
1268 struct scsiback_tpg, se_tpg);
1269 struct scsiback_tport *tport = tpg->tport;
1270
1271 return &tport->tport_name[0];
1272}
1273
1274static u16 scsiback_get_tag(struct se_portal_group *se_tpg)
1275{
1276 struct scsiback_tpg *tpg = container_of(se_tpg,
1277 struct scsiback_tpg, se_tpg);
1278 return tpg->tport_tpgt;
1279}
1280
1281static struct se_wwn *
1282scsiback_make_tport(struct target_fabric_configfs *tf,
1283 struct config_group *group,
1284 const char *name)
1285{
1286 struct scsiback_tport *tport;
1287 char *ptr;
1288 u64 wwpn = 0;
1289 int off = 0;
1290
1291 tport = kzalloc(sizeof(struct scsiback_tport), GFP_KERNEL);
1292 if (!tport)
1293 return ERR_PTR(-ENOMEM);
1294
1295 tport->tport_wwpn = wwpn;
1296
1297
1298
1299
1300 ptr = strstr(name, "naa.");
1301 if (ptr) {
1302 tport->tport_proto_id = SCSI_PROTOCOL_SAS;
1303 goto check_len;
1304 }
1305 ptr = strstr(name, "fc.");
1306 if (ptr) {
1307 tport->tport_proto_id = SCSI_PROTOCOL_FCP;
1308 off = 3;
1309 goto check_len;
1310 }
1311 ptr = strstr(name, "iqn.");
1312 if (ptr) {
1313 tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
1314 goto check_len;
1315 }
1316
1317 pr_err("Unable to locate prefix for emulated Target Port: %s\n", name);
1318 kfree(tport);
1319 return ERR_PTR(-EINVAL);
1320
1321check_len:
1322 if (strlen(name) >= VSCSI_NAMELEN) {
1323 pr_err("Emulated %s Address: %s, exceeds max: %d\n", name,
1324 scsiback_dump_proto_id(tport), VSCSI_NAMELEN);
1325 kfree(tport);
1326 return ERR_PTR(-EINVAL);
1327 }
1328 snprintf(&tport->tport_name[0], VSCSI_NAMELEN, "%s", &name[off]);
1329
1330 pr_debug("Allocated emulated Target %s Address: %s\n",
1331 scsiback_dump_proto_id(tport), name);
1332
1333 return &tport->tport_wwn;
1334}
1335
1336static void scsiback_drop_tport(struct se_wwn *wwn)
1337{
1338 struct scsiback_tport *tport = container_of(wwn,
1339 struct scsiback_tport, tport_wwn);
1340
1341 pr_debug("Deallocating emulated Target %s Address: %s\n",
1342 scsiback_dump_proto_id(tport), tport->tport_name);
1343
1344 kfree(tport);
1345}
1346
1347static u32 scsiback_tpg_get_inst_index(struct se_portal_group *se_tpg)
1348{
1349 return 1;
1350}
1351
1352static int scsiback_check_stop_free(struct se_cmd *se_cmd)
1353{
1354 return transport_generic_free_cmd(se_cmd, 0);
1355}
1356
1357static void scsiback_release_cmd(struct se_cmd *se_cmd)
1358{
1359 target_free_tag(se_cmd->se_sess, se_cmd);
1360}
1361
1362static u32 scsiback_sess_get_index(struct se_session *se_sess)
1363{
1364 return 0;
1365}
1366
1367static int scsiback_write_pending(struct se_cmd *se_cmd)
1368{
1369
1370 target_execute_cmd(se_cmd);
1371
1372 return 0;
1373}
1374
1375static void scsiback_set_default_node_attrs(struct se_node_acl *nacl)
1376{
1377}
1378
1379static int scsiback_get_cmd_state(struct se_cmd *se_cmd)
1380{
1381 return 0;
1382}
1383
1384static int scsiback_queue_data_in(struct se_cmd *se_cmd)
1385{
1386 struct vscsibk_pend *pending_req = container_of(se_cmd,
1387 struct vscsibk_pend, se_cmd);
1388
1389 pending_req->result = SAM_STAT_GOOD;
1390 scsiback_cmd_done(pending_req);
1391 return 0;
1392}
1393
1394static int scsiback_queue_status(struct se_cmd *se_cmd)
1395{
1396 struct vscsibk_pend *pending_req = container_of(se_cmd,
1397 struct vscsibk_pend, se_cmd);
1398
1399 if (se_cmd->sense_buffer &&
1400 ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
1401 (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE)))
1402 pending_req->result = SAM_STAT_CHECK_CONDITION;
1403 else
1404 pending_req->result = se_cmd->scsi_status;
1405
1406 scsiback_cmd_done(pending_req);
1407 return 0;
1408}
1409
1410static void scsiback_queue_tm_rsp(struct se_cmd *se_cmd)
1411{
1412 struct vscsibk_pend *pending_req = container_of(se_cmd,
1413 struct vscsibk_pend, se_cmd);
1414
1415 complete(&pending_req->tmr_done);
1416}
1417
1418static void scsiback_aborted_task(struct se_cmd *se_cmd)
1419{
1420}
1421
1422static ssize_t scsiback_tpg_param_alias_show(struct config_item *item,
1423 char *page)
1424{
1425 struct se_portal_group *se_tpg = param_to_tpg(item);
1426 struct scsiback_tpg *tpg = container_of(se_tpg, struct scsiback_tpg,
1427 se_tpg);
1428 ssize_t rb;
1429
1430 mutex_lock(&tpg->tv_tpg_mutex);
1431 rb = snprintf(page, PAGE_SIZE, "%s\n", tpg->param_alias);
1432 mutex_unlock(&tpg->tv_tpg_mutex);
1433
1434 return rb;
1435}
1436
1437static ssize_t scsiback_tpg_param_alias_store(struct config_item *item,
1438 const char *page, size_t count)
1439{
1440 struct se_portal_group *se_tpg = param_to_tpg(item);
1441 struct scsiback_tpg *tpg = container_of(se_tpg, struct scsiback_tpg,
1442 se_tpg);
1443 int len;
1444
1445 if (strlen(page) >= VSCSI_NAMELEN) {
1446 pr_err("param alias: %s, exceeds max: %d\n", page,
1447 VSCSI_NAMELEN);
1448 return -EINVAL;
1449 }
1450
1451 mutex_lock(&tpg->tv_tpg_mutex);
1452 len = snprintf(tpg->param_alias, VSCSI_NAMELEN, "%s", page);
1453 if (tpg->param_alias[len - 1] == '\n')
1454 tpg->param_alias[len - 1] = '\0';
1455 mutex_unlock(&tpg->tv_tpg_mutex);
1456
1457 return count;
1458}
1459
1460CONFIGFS_ATTR(scsiback_tpg_param_, alias);
1461
1462static struct configfs_attribute *scsiback_param_attrs[] = {
1463 &scsiback_tpg_param_attr_alias,
1464 NULL,
1465};
1466
1467static int scsiback_alloc_sess_cb(struct se_portal_group *se_tpg,
1468 struct se_session *se_sess, void *p)
1469{
1470 struct scsiback_tpg *tpg = container_of(se_tpg,
1471 struct scsiback_tpg, se_tpg);
1472
1473 tpg->tpg_nexus = p;
1474 return 0;
1475}
1476
1477static int scsiback_make_nexus(struct scsiback_tpg *tpg,
1478 const char *name)
1479{
1480 struct scsiback_nexus *tv_nexus;
1481 int ret = 0;
1482
1483 mutex_lock(&tpg->tv_tpg_mutex);
1484 if (tpg->tpg_nexus) {
1485 pr_debug("tpg->tpg_nexus already exists\n");
1486 ret = -EEXIST;
1487 goto out_unlock;
1488 }
1489
1490 tv_nexus = kzalloc(sizeof(struct scsiback_nexus), GFP_KERNEL);
1491 if (!tv_nexus) {
1492 ret = -ENOMEM;
1493 goto out_unlock;
1494 }
1495
1496 tv_nexus->tvn_se_sess = target_setup_session(&tpg->se_tpg,
1497 VSCSI_DEFAULT_SESSION_TAGS,
1498 sizeof(struct vscsibk_pend),
1499 TARGET_PROT_NORMAL, name,
1500 tv_nexus, scsiback_alloc_sess_cb);
1501 if (IS_ERR(tv_nexus->tvn_se_sess)) {
1502 kfree(tv_nexus);
1503 ret = -ENOMEM;
1504 goto out_unlock;
1505 }
1506
1507out_unlock:
1508 mutex_unlock(&tpg->tv_tpg_mutex);
1509 return ret;
1510}
1511
1512static int scsiback_drop_nexus(struct scsiback_tpg *tpg)
1513{
1514 struct se_session *se_sess;
1515 struct scsiback_nexus *tv_nexus;
1516
1517 mutex_lock(&tpg->tv_tpg_mutex);
1518 tv_nexus = tpg->tpg_nexus;
1519 if (!tv_nexus) {
1520 mutex_unlock(&tpg->tv_tpg_mutex);
1521 return -ENODEV;
1522 }
1523
1524 se_sess = tv_nexus->tvn_se_sess;
1525 if (!se_sess) {
1526 mutex_unlock(&tpg->tv_tpg_mutex);
1527 return -ENODEV;
1528 }
1529
1530 if (tpg->tv_tpg_port_count != 0) {
1531 mutex_unlock(&tpg->tv_tpg_mutex);
1532 pr_err("Unable to remove xen-pvscsi I_T Nexus with active TPG port count: %d\n",
1533 tpg->tv_tpg_port_count);
1534 return -EBUSY;
1535 }
1536
1537 if (tpg->tv_tpg_fe_count != 0) {
1538 mutex_unlock(&tpg->tv_tpg_mutex);
1539 pr_err("Unable to remove xen-pvscsi I_T Nexus with active TPG frontend count: %d\n",
1540 tpg->tv_tpg_fe_count);
1541 return -EBUSY;
1542 }
1543
1544 pr_debug("Removing I_T Nexus to emulated %s Initiator Port: %s\n",
1545 scsiback_dump_proto_id(tpg->tport),
1546 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1547
1548
1549
1550
1551 target_remove_session(se_sess);
1552 tpg->tpg_nexus = NULL;
1553 mutex_unlock(&tpg->tv_tpg_mutex);
1554
1555 kfree(tv_nexus);
1556 return 0;
1557}
1558
1559static ssize_t scsiback_tpg_nexus_show(struct config_item *item, char *page)
1560{
1561 struct se_portal_group *se_tpg = to_tpg(item);
1562 struct scsiback_tpg *tpg = container_of(se_tpg,
1563 struct scsiback_tpg, se_tpg);
1564 struct scsiback_nexus *tv_nexus;
1565 ssize_t ret;
1566
1567 mutex_lock(&tpg->tv_tpg_mutex);
1568 tv_nexus = tpg->tpg_nexus;
1569 if (!tv_nexus) {
1570 mutex_unlock(&tpg->tv_tpg_mutex);
1571 return -ENODEV;
1572 }
1573 ret = snprintf(page, PAGE_SIZE, "%s\n",
1574 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1575 mutex_unlock(&tpg->tv_tpg_mutex);
1576
1577 return ret;
1578}
1579
1580static ssize_t scsiback_tpg_nexus_store(struct config_item *item,
1581 const char *page, size_t count)
1582{
1583 struct se_portal_group *se_tpg = to_tpg(item);
1584 struct scsiback_tpg *tpg = container_of(se_tpg,
1585 struct scsiback_tpg, se_tpg);
1586 struct scsiback_tport *tport_wwn = tpg->tport;
1587 unsigned char i_port[VSCSI_NAMELEN], *ptr, *port_ptr;
1588 int ret;
1589
1590
1591
1592 if (!strncmp(page, "NULL", 4)) {
1593 ret = scsiback_drop_nexus(tpg);
1594 return (!ret) ? count : ret;
1595 }
1596
1597
1598
1599
1600
1601 if (strlen(page) >= VSCSI_NAMELEN) {
1602 pr_err("Emulated NAA Sas Address: %s, exceeds max: %d\n",
1603 page, VSCSI_NAMELEN);
1604 return -EINVAL;
1605 }
1606 snprintf(&i_port[0], VSCSI_NAMELEN, "%s", page);
1607
1608 ptr = strstr(i_port, "naa.");
1609 if (ptr) {
1610 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
1611 pr_err("Passed SAS Initiator Port %s does not match target port protoid: %s\n",
1612 i_port, scsiback_dump_proto_id(tport_wwn));
1613 return -EINVAL;
1614 }
1615 port_ptr = &i_port[0];
1616 goto check_newline;
1617 }
1618 ptr = strstr(i_port, "fc.");
1619 if (ptr) {
1620 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
1621 pr_err("Passed FCP Initiator Port %s does not match target port protoid: %s\n",
1622 i_port, scsiback_dump_proto_id(tport_wwn));
1623 return -EINVAL;
1624 }
1625 port_ptr = &i_port[3];
1626 goto check_newline;
1627 }
1628 ptr = strstr(i_port, "iqn.");
1629 if (ptr) {
1630 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
1631 pr_err("Passed iSCSI Initiator Port %s does not match target port protoid: %s\n",
1632 i_port, scsiback_dump_proto_id(tport_wwn));
1633 return -EINVAL;
1634 }
1635 port_ptr = &i_port[0];
1636 goto check_newline;
1637 }
1638 pr_err("Unable to locate prefix for emulated Initiator Port: %s\n",
1639 i_port);
1640 return -EINVAL;
1641
1642
1643
1644check_newline:
1645 if (i_port[strlen(i_port) - 1] == '\n')
1646 i_port[strlen(i_port) - 1] = '\0';
1647
1648 ret = scsiback_make_nexus(tpg, port_ptr);
1649 if (ret < 0)
1650 return ret;
1651
1652 return count;
1653}
1654
1655CONFIGFS_ATTR(scsiback_tpg_, nexus);
1656
1657static struct configfs_attribute *scsiback_tpg_attrs[] = {
1658 &scsiback_tpg_attr_nexus,
1659 NULL,
1660};
1661
1662static ssize_t
1663scsiback_wwn_version_show(struct config_item *item, char *page)
1664{
1665 return sprintf(page, "xen-pvscsi fabric module %s on %s/%s on "
1666 UTS_RELEASE"\n",
1667 VSCSI_VERSION, utsname()->sysname, utsname()->machine);
1668}
1669
1670CONFIGFS_ATTR_RO(scsiback_wwn_, version);
1671
1672static struct configfs_attribute *scsiback_wwn_attrs[] = {
1673 &scsiback_wwn_attr_version,
1674 NULL,
1675};
1676
1677static int scsiback_port_link(struct se_portal_group *se_tpg,
1678 struct se_lun *lun)
1679{
1680 struct scsiback_tpg *tpg = container_of(se_tpg,
1681 struct scsiback_tpg, se_tpg);
1682
1683 mutex_lock(&tpg->tv_tpg_mutex);
1684 tpg->tv_tpg_port_count++;
1685 mutex_unlock(&tpg->tv_tpg_mutex);
1686
1687 return 0;
1688}
1689
1690static void scsiback_port_unlink(struct se_portal_group *se_tpg,
1691 struct se_lun *lun)
1692{
1693 struct scsiback_tpg *tpg = container_of(se_tpg,
1694 struct scsiback_tpg, se_tpg);
1695
1696 mutex_lock(&tpg->tv_tpg_mutex);
1697 tpg->tv_tpg_port_count--;
1698 mutex_unlock(&tpg->tv_tpg_mutex);
1699}
1700
1701static struct se_portal_group *
1702scsiback_make_tpg(struct se_wwn *wwn, const char *name)
1703{
1704 struct scsiback_tport *tport = container_of(wwn,
1705 struct scsiback_tport, tport_wwn);
1706
1707 struct scsiback_tpg *tpg;
1708 u16 tpgt;
1709 int ret;
1710
1711 if (strstr(name, "tpgt_") != name)
1712 return ERR_PTR(-EINVAL);
1713 ret = kstrtou16(name + 5, 10, &tpgt);
1714 if (ret)
1715 return ERR_PTR(ret);
1716
1717 tpg = kzalloc(sizeof(struct scsiback_tpg), GFP_KERNEL);
1718 if (!tpg)
1719 return ERR_PTR(-ENOMEM);
1720
1721 mutex_init(&tpg->tv_tpg_mutex);
1722 INIT_LIST_HEAD(&tpg->tv_tpg_list);
1723 INIT_LIST_HEAD(&tpg->info_list);
1724 tpg->tport = tport;
1725 tpg->tport_tpgt = tpgt;
1726
1727 ret = core_tpg_register(wwn, &tpg->se_tpg, tport->tport_proto_id);
1728 if (ret < 0) {
1729 kfree(tpg);
1730 return NULL;
1731 }
1732 mutex_lock(&scsiback_mutex);
1733 list_add_tail(&tpg->tv_tpg_list, &scsiback_list);
1734 mutex_unlock(&scsiback_mutex);
1735
1736 return &tpg->se_tpg;
1737}
1738
1739static void scsiback_drop_tpg(struct se_portal_group *se_tpg)
1740{
1741 struct scsiback_tpg *tpg = container_of(se_tpg,
1742 struct scsiback_tpg, se_tpg);
1743
1744 mutex_lock(&scsiback_mutex);
1745 list_del(&tpg->tv_tpg_list);
1746 mutex_unlock(&scsiback_mutex);
1747
1748
1749
1750 scsiback_drop_nexus(tpg);
1751
1752
1753
1754 core_tpg_deregister(se_tpg);
1755 kfree(tpg);
1756}
1757
1758static int scsiback_check_true(struct se_portal_group *se_tpg)
1759{
1760 return 1;
1761}
1762
1763static int scsiback_check_false(struct se_portal_group *se_tpg)
1764{
1765 return 0;
1766}
1767
1768static const struct target_core_fabric_ops scsiback_ops = {
1769 .module = THIS_MODULE,
1770 .fabric_name = "xen-pvscsi",
1771 .tpg_get_wwn = scsiback_get_fabric_wwn,
1772 .tpg_get_tag = scsiback_get_tag,
1773 .tpg_check_demo_mode = scsiback_check_true,
1774 .tpg_check_demo_mode_cache = scsiback_check_true,
1775 .tpg_check_demo_mode_write_protect = scsiback_check_false,
1776 .tpg_check_prod_mode_write_protect = scsiback_check_false,
1777 .tpg_get_inst_index = scsiback_tpg_get_inst_index,
1778 .check_stop_free = scsiback_check_stop_free,
1779 .release_cmd = scsiback_release_cmd,
1780 .sess_get_index = scsiback_sess_get_index,
1781 .sess_get_initiator_sid = NULL,
1782 .write_pending = scsiback_write_pending,
1783 .set_default_node_attributes = scsiback_set_default_node_attrs,
1784 .get_cmd_state = scsiback_get_cmd_state,
1785 .queue_data_in = scsiback_queue_data_in,
1786 .queue_status = scsiback_queue_status,
1787 .queue_tm_rsp = scsiback_queue_tm_rsp,
1788 .aborted_task = scsiback_aborted_task,
1789
1790
1791
1792 .fabric_make_wwn = scsiback_make_tport,
1793 .fabric_drop_wwn = scsiback_drop_tport,
1794 .fabric_make_tpg = scsiback_make_tpg,
1795 .fabric_drop_tpg = scsiback_drop_tpg,
1796 .fabric_post_link = scsiback_port_link,
1797 .fabric_pre_unlink = scsiback_port_unlink,
1798
1799 .tfc_wwn_attrs = scsiback_wwn_attrs,
1800 .tfc_tpg_base_attrs = scsiback_tpg_attrs,
1801 .tfc_tpg_param_attrs = scsiback_param_attrs,
1802};
1803
1804static const struct xenbus_device_id scsiback_ids[] = {
1805 { "vscsi" },
1806 { "" }
1807};
1808
1809static struct xenbus_driver scsiback_driver = {
1810 .ids = scsiback_ids,
1811 .probe = scsiback_probe,
1812 .remove = scsiback_remove,
1813 .otherend_changed = scsiback_frontend_changed
1814};
1815
1816static int __init scsiback_init(void)
1817{
1818 int ret;
1819
1820 if (!xen_domain())
1821 return -ENODEV;
1822
1823 pr_debug("xen-pvscsi: fabric module %s on %s/%s on "UTS_RELEASE"\n",
1824 VSCSI_VERSION, utsname()->sysname, utsname()->machine);
1825
1826 ret = xenbus_register_backend(&scsiback_driver);
1827 if (ret)
1828 goto out;
1829
1830 ret = target_register_template(&scsiback_ops);
1831 if (ret)
1832 goto out_unregister_xenbus;
1833
1834 return 0;
1835
1836out_unregister_xenbus:
1837 xenbus_unregister_driver(&scsiback_driver);
1838out:
1839 pr_err("%s: error %d\n", __func__, ret);
1840 return ret;
1841}
1842
1843static void __exit scsiback_exit(void)
1844{
1845 target_unregister_template(&scsiback_ops);
1846 xenbus_unregister_driver(&scsiback_driver);
1847}
1848
1849module_init(scsiback_init);
1850module_exit(scsiback_exit);
1851
1852MODULE_DESCRIPTION("Xen SCSI backend driver");
1853MODULE_LICENSE("Dual BSD/GPL");
1854MODULE_ALIAS("xen-backend:vscsi");
1855MODULE_AUTHOR("Juergen Gross <jgross@suse.com>");
1856
