ARM: pmu: add support for interrupt-affinity property
[linux/fpc-iii.git] / drivers / xen / xen-scsiback.c
blob9faca6a60bb01b33c311f86b01af239280934a78
1 /*
2 * Xen SCSI backend driver
4 * Copyright (c) 2008, FUJITSU Limited
6 * Based on the blkback driver code.
7 * Adaption to kernel taget core infrastructure taken from vhost/scsi.c
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License version 2
11 * as published by the Free Software Foundation; or, when distributed
12 * separately from the Linux kernel or incorporated into other
13 * software packages, subject to the following license:
15 * Permission is hereby granted, free of charge, to any person obtaining a copy
16 * of this source file (the "Software"), to deal in the Software without
17 * restriction, including without limitation the rights to use, copy, modify,
18 * merge, publish, distribute, sublicense, and/or sell copies of the Software,
19 * and to permit persons to whom the Software is furnished to do so, subject to
20 * the following conditions:
22 * The above copyright notice and this permission notice shall be included in
23 * all copies or substantial portions of the Software.
25 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
26 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
27 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
28 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
29 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
30 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
31 * IN THE SOFTWARE.
34 #include <stdarg.h>
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>
48 #include <generated/utsrelease.h>
50 #include <scsi/scsi.h>
51 #include <scsi/scsi_dbg.h>
52 #include <scsi/scsi_eh.h>
53 #include <scsi/scsi_tcq.h>
55 #include <target/target_core_base.h>
56 #include <target/target_core_fabric.h>
57 #include <target/target_core_configfs.h>
58 #include <target/target_core_fabric_configfs.h>
60 #include <asm/hypervisor.h>
62 #include <xen/xen.h>
63 #include <xen/balloon.h>
64 #include <xen/events.h>
65 #include <xen/xenbus.h>
66 #include <xen/grant_table.h>
67 #include <xen/page.h>
69 #include <xen/interface/grant_table.h>
70 #include <xen/interface/io/vscsiif.h>
72 #define DPRINTK(_f, _a...) \
73 pr_debug("(file=%s, line=%d) " _f, __FILE__ , __LINE__ , ## _a)
75 #define VSCSI_VERSION "v0.1"
76 #define VSCSI_NAMELEN 32
78 struct ids_tuple {
79 unsigned int hst; /* host */
80 unsigned int chn; /* channel */
81 unsigned int tgt; /* target */
82 unsigned int lun; /* LUN */
85 struct v2p_entry {
86 struct ids_tuple v; /* translate from */
87 struct scsiback_tpg *tpg; /* translate to */
88 unsigned int lun;
89 struct kref kref;
90 struct list_head l;
93 struct vscsibk_info {
94 struct xenbus_device *dev;
96 domid_t domid;
97 unsigned int irq;
99 struct vscsiif_back_ring ring;
100 int ring_error;
102 spinlock_t ring_lock;
103 atomic_t nr_unreplied_reqs;
105 spinlock_t v2p_lock;
106 struct list_head v2p_entry_lists;
108 wait_queue_head_t waiting_to_free;
111 /* theoretical maximum of grants for one request */
112 #define VSCSI_MAX_GRANTS (SG_ALL + VSCSIIF_SG_TABLESIZE)
115 * VSCSI_GRANT_BATCH is the maximum number of grants to be processed in one
116 * call to map/unmap grants. Don't choose it too large, as there are arrays
117 * with VSCSI_GRANT_BATCH elements allocated on the stack.
119 #define VSCSI_GRANT_BATCH 16
121 struct vscsibk_pend {
122 uint16_t rqid;
124 uint8_t cmnd[VSCSIIF_MAX_COMMAND_SIZE];
125 uint8_t cmd_len;
127 uint8_t sc_data_direction;
128 uint16_t n_sg; /* real length of SG list */
129 uint16_t n_grants; /* SG pages and potentially SG list */
130 uint32_t data_len;
131 uint32_t result;
133 struct vscsibk_info *info;
134 struct v2p_entry *v2p;
135 struct scatterlist *sgl;
137 uint8_t sense_buffer[VSCSIIF_SENSE_BUFFERSIZE];
139 grant_handle_t grant_handles[VSCSI_MAX_GRANTS];
140 struct page *pages[VSCSI_MAX_GRANTS];
142 struct se_cmd se_cmd;
145 struct scsiback_tmr {
146 atomic_t tmr_complete;
147 wait_queue_head_t tmr_wait;
150 struct scsiback_nexus {
151 /* Pointer to TCM session for I_T Nexus */
152 struct se_session *tvn_se_sess;
155 struct scsiback_tport {
156 /* SCSI protocol the tport is providing */
157 u8 tport_proto_id;
158 /* Binary World Wide unique Port Name for pvscsi Target port */
159 u64 tport_wwpn;
160 /* ASCII formatted WWPN for pvscsi Target port */
161 char tport_name[VSCSI_NAMELEN];
162 /* Returned by scsiback_make_tport() */
163 struct se_wwn tport_wwn;
166 struct scsiback_tpg {
167 /* scsiback port target portal group tag for TCM */
168 u16 tport_tpgt;
169 /* track number of TPG Port/Lun Links wrt explicit I_T Nexus shutdown */
170 int tv_tpg_port_count;
171 /* xen-pvscsi references to tpg_nexus, protected by tv_tpg_mutex */
172 int tv_tpg_fe_count;
173 /* list for scsiback_list */
174 struct list_head tv_tpg_list;
175 /* Used to protect access for tpg_nexus */
176 struct mutex tv_tpg_mutex;
177 /* Pointer to the TCM pvscsi I_T Nexus for this TPG endpoint */
178 struct scsiback_nexus *tpg_nexus;
179 /* Pointer back to scsiback_tport */
180 struct scsiback_tport *tport;
181 /* Returned by scsiback_make_tpg() */
182 struct se_portal_group se_tpg;
183 /* alias used in xenstore */
184 char param_alias[VSCSI_NAMELEN];
185 /* list of info structures related to this target portal group */
186 struct list_head info_list;
189 #define SCSIBACK_INVALID_HANDLE (~0)
191 static bool log_print_stat;
192 module_param(log_print_stat, bool, 0644);
194 static int scsiback_max_buffer_pages = 1024;
195 module_param_named(max_buffer_pages, scsiback_max_buffer_pages, int, 0644);
196 MODULE_PARM_DESC(max_buffer_pages,
197 "Maximum number of free pages to keep in backend buffer");
199 static struct kmem_cache *scsiback_cachep;
200 static DEFINE_SPINLOCK(free_pages_lock);
201 static int free_pages_num;
202 static LIST_HEAD(scsiback_free_pages);
204 /* Global spinlock to protect scsiback TPG list */
205 static DEFINE_MUTEX(scsiback_mutex);
206 static LIST_HEAD(scsiback_list);
208 /* Local pointer to allocated TCM configfs fabric module */
209 static struct target_fabric_configfs *scsiback_fabric_configfs;
211 static void scsiback_get(struct vscsibk_info *info)
213 atomic_inc(&info->nr_unreplied_reqs);
216 static void scsiback_put(struct vscsibk_info *info)
218 if (atomic_dec_and_test(&info->nr_unreplied_reqs))
219 wake_up(&info->waiting_to_free);
222 static void put_free_pages(struct page **page, int num)
224 unsigned long flags;
225 int i = free_pages_num + num, n = num;
227 if (num == 0)
228 return;
229 if (i > scsiback_max_buffer_pages) {
230 n = min(num, i - scsiback_max_buffer_pages);
231 gnttab_free_pages(n, page + num - n);
232 n = num - n;
234 spin_lock_irqsave(&free_pages_lock, flags);
235 for (i = 0; i < n; i++)
236 list_add(&page[i]->lru, &scsiback_free_pages);
237 free_pages_num += n;
238 spin_unlock_irqrestore(&free_pages_lock, flags);
241 static int get_free_page(struct page **page)
243 unsigned long flags;
245 spin_lock_irqsave(&free_pages_lock, flags);
246 if (list_empty(&scsiback_free_pages)) {
247 spin_unlock_irqrestore(&free_pages_lock, flags);
248 return gnttab_alloc_pages(1, page);
250 page[0] = list_first_entry(&scsiback_free_pages, struct page, lru);
251 list_del(&page[0]->lru);
252 free_pages_num--;
253 spin_unlock_irqrestore(&free_pages_lock, flags);
254 return 0;
257 static unsigned long vaddr_page(struct page *page)
259 unsigned long pfn = page_to_pfn(page);
261 return (unsigned long)pfn_to_kaddr(pfn);
264 static unsigned long vaddr(struct vscsibk_pend *req, int seg)
266 return vaddr_page(req->pages[seg]);
269 static void scsiback_print_status(char *sense_buffer, int errors,
270 struct vscsibk_pend *pending_req)
272 struct scsiback_tpg *tpg = pending_req->v2p->tpg;
274 pr_err("xen-pvscsi[%s:%d] cmnd[0]=%02x -> st=%02x msg=%02x host=%02x drv=%02x\n",
275 tpg->tport->tport_name, pending_req->v2p->lun,
276 pending_req->cmnd[0], status_byte(errors), msg_byte(errors),
277 host_byte(errors), driver_byte(errors));
280 static void scsiback_fast_flush_area(struct vscsibk_pend *req)
282 struct gnttab_unmap_grant_ref unmap[VSCSI_GRANT_BATCH];
283 struct page *pages[VSCSI_GRANT_BATCH];
284 unsigned int i, invcount = 0;
285 grant_handle_t handle;
286 int err;
288 kfree(req->sgl);
289 req->sgl = NULL;
290 req->n_sg = 0;
292 if (!req->n_grants)
293 return;
295 for (i = 0; i < req->n_grants; i++) {
296 handle = req->grant_handles[i];
297 if (handle == SCSIBACK_INVALID_HANDLE)
298 continue;
299 gnttab_set_unmap_op(&unmap[invcount], vaddr(req, i),
300 GNTMAP_host_map, handle);
301 req->grant_handles[i] = SCSIBACK_INVALID_HANDLE;
302 pages[invcount] = req->pages[i];
303 put_page(pages[invcount]);
304 invcount++;
305 if (invcount < VSCSI_GRANT_BATCH)
306 continue;
307 err = gnttab_unmap_refs(unmap, NULL, pages, invcount);
308 BUG_ON(err);
309 invcount = 0;
312 if (invcount) {
313 err = gnttab_unmap_refs(unmap, NULL, pages, invcount);
314 BUG_ON(err);
317 put_free_pages(req->pages, req->n_grants);
318 req->n_grants = 0;
321 static void scsiback_free_translation_entry(struct kref *kref)
323 struct v2p_entry *entry = container_of(kref, struct v2p_entry, kref);
324 struct scsiback_tpg *tpg = entry->tpg;
326 mutex_lock(&tpg->tv_tpg_mutex);
327 tpg->tv_tpg_fe_count--;
328 mutex_unlock(&tpg->tv_tpg_mutex);
330 kfree(entry);
333 static void scsiback_do_resp_with_sense(char *sense_buffer, int32_t result,
334 uint32_t resid, struct vscsibk_pend *pending_req)
336 struct vscsiif_response *ring_res;
337 struct vscsibk_info *info = pending_req->info;
338 int notify;
339 struct scsi_sense_hdr sshdr;
340 unsigned long flags;
341 unsigned len;
343 spin_lock_irqsave(&info->ring_lock, flags);
345 ring_res = RING_GET_RESPONSE(&info->ring, info->ring.rsp_prod_pvt);
346 info->ring.rsp_prod_pvt++;
348 ring_res->rslt = result;
349 ring_res->rqid = pending_req->rqid;
351 if (sense_buffer != NULL &&
352 scsi_normalize_sense(sense_buffer, VSCSIIF_SENSE_BUFFERSIZE,
353 &sshdr)) {
354 len = min_t(unsigned, 8 + sense_buffer[7],
355 VSCSIIF_SENSE_BUFFERSIZE);
356 memcpy(ring_res->sense_buffer, sense_buffer, len);
357 ring_res->sense_len = len;
358 } else {
359 ring_res->sense_len = 0;
362 ring_res->residual_len = resid;
364 RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&info->ring, notify);
365 spin_unlock_irqrestore(&info->ring_lock, flags);
367 if (notify)
368 notify_remote_via_irq(info->irq);
370 if (pending_req->v2p)
371 kref_put(&pending_req->v2p->kref,
372 scsiback_free_translation_entry);
375 static void scsiback_cmd_done(struct vscsibk_pend *pending_req)
377 struct vscsibk_info *info = pending_req->info;
378 unsigned char *sense_buffer;
379 unsigned int resid;
380 int errors;
382 sense_buffer = pending_req->sense_buffer;
383 resid = pending_req->se_cmd.residual_count;
384 errors = pending_req->result;
386 if (errors && log_print_stat)
387 scsiback_print_status(sense_buffer, errors, pending_req);
389 scsiback_fast_flush_area(pending_req);
390 scsiback_do_resp_with_sense(sense_buffer, errors, resid, pending_req);
391 scsiback_put(info);
394 static void scsiback_cmd_exec(struct vscsibk_pend *pending_req)
396 struct se_cmd *se_cmd = &pending_req->se_cmd;
397 struct se_session *sess = pending_req->v2p->tpg->tpg_nexus->tvn_se_sess;
398 int rc;
400 memset(pending_req->sense_buffer, 0, VSCSIIF_SENSE_BUFFERSIZE);
402 memset(se_cmd, 0, sizeof(*se_cmd));
404 scsiback_get(pending_req->info);
405 rc = target_submit_cmd_map_sgls(se_cmd, sess, pending_req->cmnd,
406 pending_req->sense_buffer, pending_req->v2p->lun,
407 pending_req->data_len, 0,
408 pending_req->sc_data_direction, 0,
409 pending_req->sgl, pending_req->n_sg,
410 NULL, 0, NULL, 0);
411 if (rc < 0) {
412 transport_send_check_condition_and_sense(se_cmd,
413 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
414 transport_generic_free_cmd(se_cmd, 0);
418 static int scsiback_gnttab_data_map_batch(struct gnttab_map_grant_ref *map,
419 struct page **pg, grant_handle_t *grant, int cnt)
421 int err, i;
423 if (!cnt)
424 return 0;
426 err = gnttab_map_refs(map, NULL, pg, cnt);
427 BUG_ON(err);
428 for (i = 0; i < cnt; i++) {
429 if (unlikely(map[i].status != GNTST_okay)) {
430 pr_err("xen-pvscsi: invalid buffer -- could not remap it\n");
431 map[i].handle = SCSIBACK_INVALID_HANDLE;
432 err = -ENOMEM;
433 } else {
434 get_page(pg[i]);
436 grant[i] = map[i].handle;
438 return err;
441 static int scsiback_gnttab_data_map_list(struct vscsibk_pend *pending_req,
442 struct scsiif_request_segment *seg, struct page **pg,
443 grant_handle_t *grant, int cnt, u32 flags)
445 int mapcount = 0, i, err = 0;
446 struct gnttab_map_grant_ref map[VSCSI_GRANT_BATCH];
447 struct vscsibk_info *info = pending_req->info;
449 for (i = 0; i < cnt; i++) {
450 if (get_free_page(pg + mapcount)) {
451 put_free_pages(pg, mapcount);
452 pr_err("xen-pvscsi: no grant page\n");
453 return -ENOMEM;
455 gnttab_set_map_op(&map[mapcount], vaddr_page(pg[mapcount]),
456 flags, seg[i].gref, info->domid);
457 mapcount++;
458 if (mapcount < VSCSI_GRANT_BATCH)
459 continue;
460 err = scsiback_gnttab_data_map_batch(map, pg, grant, mapcount);
461 pg += mapcount;
462 grant += mapcount;
463 pending_req->n_grants += mapcount;
464 if (err)
465 return err;
466 mapcount = 0;
468 err = scsiback_gnttab_data_map_batch(map, pg, grant, mapcount);
469 pending_req->n_grants += mapcount;
470 return err;
473 static int scsiback_gnttab_data_map(struct vscsiif_request *ring_req,
474 struct vscsibk_pend *pending_req)
476 u32 flags;
477 int i, err, n_segs, i_seg = 0;
478 struct page **pg;
479 struct scsiif_request_segment *seg;
480 unsigned long end_seg = 0;
481 unsigned int nr_segments = (unsigned int)ring_req->nr_segments;
482 unsigned int nr_sgl = 0;
483 struct scatterlist *sg;
484 grant_handle_t *grant;
486 pending_req->n_sg = 0;
487 pending_req->n_grants = 0;
488 pending_req->data_len = 0;
490 nr_segments &= ~VSCSIIF_SG_GRANT;
491 if (!nr_segments)
492 return 0;
494 if (nr_segments > VSCSIIF_SG_TABLESIZE) {
495 DPRINTK("xen-pvscsi: invalid parameter nr_seg = %d\n",
496 ring_req->nr_segments);
497 return -EINVAL;
500 if (ring_req->nr_segments & VSCSIIF_SG_GRANT) {
501 err = scsiback_gnttab_data_map_list(pending_req, ring_req->seg,
502 pending_req->pages, pending_req->grant_handles,
503 nr_segments, GNTMAP_host_map | GNTMAP_readonly);
504 if (err)
505 return err;
506 nr_sgl = nr_segments;
507 nr_segments = 0;
508 for (i = 0; i < nr_sgl; i++) {
509 n_segs = ring_req->seg[i].length /
510 sizeof(struct scsiif_request_segment);
511 if ((unsigned)ring_req->seg[i].offset +
512 (unsigned)ring_req->seg[i].length > PAGE_SIZE ||
513 n_segs * sizeof(struct scsiif_request_segment) !=
514 ring_req->seg[i].length)
515 return -EINVAL;
516 nr_segments += n_segs;
518 if (nr_segments > SG_ALL) {
519 DPRINTK("xen-pvscsi: invalid nr_seg = %d\n",
520 nr_segments);
521 return -EINVAL;
525 /* free of (sgl) in fast_flush_area()*/
526 pending_req->sgl = kmalloc_array(nr_segments,
527 sizeof(struct scatterlist), GFP_KERNEL);
528 if (!pending_req->sgl)
529 return -ENOMEM;
531 sg_init_table(pending_req->sgl, nr_segments);
532 pending_req->n_sg = nr_segments;
534 flags = GNTMAP_host_map;
535 if (pending_req->sc_data_direction == DMA_TO_DEVICE)
536 flags |= GNTMAP_readonly;
538 pg = pending_req->pages + nr_sgl;
539 grant = pending_req->grant_handles + nr_sgl;
540 if (!nr_sgl) {
541 seg = ring_req->seg;
542 err = scsiback_gnttab_data_map_list(pending_req, seg,
543 pg, grant, nr_segments, flags);
544 if (err)
545 return err;
546 } else {
547 for (i = 0; i < nr_sgl; i++) {
548 seg = (struct scsiif_request_segment *)(
549 vaddr(pending_req, i) + ring_req->seg[i].offset);
550 n_segs = ring_req->seg[i].length /
551 sizeof(struct scsiif_request_segment);
552 err = scsiback_gnttab_data_map_list(pending_req, seg,
553 pg, grant, n_segs, flags);
554 if (err)
555 return err;
556 pg += n_segs;
557 grant += n_segs;
559 end_seg = vaddr(pending_req, 0) + ring_req->seg[0].offset;
560 seg = (struct scsiif_request_segment *)end_seg;
561 end_seg += ring_req->seg[0].length;
562 pg = pending_req->pages + nr_sgl;
565 for_each_sg(pending_req->sgl, sg, nr_segments, i) {
566 sg_set_page(sg, pg[i], seg->length, seg->offset);
567 pending_req->data_len += seg->length;
568 seg++;
569 if (nr_sgl && (unsigned long)seg >= end_seg) {
570 i_seg++;
571 end_seg = vaddr(pending_req, i_seg) +
572 ring_req->seg[i_seg].offset;
573 seg = (struct scsiif_request_segment *)end_seg;
574 end_seg += ring_req->seg[i_seg].length;
576 if (sg->offset >= PAGE_SIZE ||
577 sg->length > PAGE_SIZE ||
578 sg->offset + sg->length > PAGE_SIZE)
579 return -EINVAL;
582 return 0;
585 static void scsiback_disconnect(struct vscsibk_info *info)
587 wait_event(info->waiting_to_free,
588 atomic_read(&info->nr_unreplied_reqs) == 0);
590 unbind_from_irqhandler(info->irq, info);
591 info->irq = 0;
592 xenbus_unmap_ring_vfree(info->dev, info->ring.sring);
595 static void scsiback_device_action(struct vscsibk_pend *pending_req,
596 enum tcm_tmreq_table act, int tag)
598 int rc, err = FAILED;
599 struct scsiback_tpg *tpg = pending_req->v2p->tpg;
600 struct se_cmd *se_cmd = &pending_req->se_cmd;
601 struct scsiback_tmr *tmr;
603 tmr = kzalloc(sizeof(struct scsiback_tmr), GFP_KERNEL);
604 if (!tmr)
605 goto out;
607 init_waitqueue_head(&tmr->tmr_wait);
609 transport_init_se_cmd(se_cmd, tpg->se_tpg.se_tpg_tfo,
610 tpg->tpg_nexus->tvn_se_sess, 0, DMA_NONE, TCM_SIMPLE_TAG,
611 &pending_req->sense_buffer[0]);
613 rc = core_tmr_alloc_req(se_cmd, tmr, act, GFP_KERNEL);
614 if (rc < 0)
615 goto out;
617 se_cmd->se_tmr_req->ref_task_tag = tag;
619 if (transport_lookup_tmr_lun(se_cmd, pending_req->v2p->lun) < 0)
620 goto out;
622 transport_generic_handle_tmr(se_cmd);
623 wait_event(tmr->tmr_wait, atomic_read(&tmr->tmr_complete));
625 err = (se_cmd->se_tmr_req->response == TMR_FUNCTION_COMPLETE) ?
626 SUCCESS : FAILED;
628 out:
629 if (tmr) {
630 transport_generic_free_cmd(&pending_req->se_cmd, 1);
631 kfree(tmr);
634 scsiback_do_resp_with_sense(NULL, err, 0, pending_req);
636 kmem_cache_free(scsiback_cachep, pending_req);
640 Perform virtual to physical translation
642 static struct v2p_entry *scsiback_do_translation(struct vscsibk_info *info,
643 struct ids_tuple *v)
645 struct v2p_entry *entry;
646 struct list_head *head = &(info->v2p_entry_lists);
647 unsigned long flags;
649 spin_lock_irqsave(&info->v2p_lock, flags);
650 list_for_each_entry(entry, head, l) {
651 if ((entry->v.chn == v->chn) &&
652 (entry->v.tgt == v->tgt) &&
653 (entry->v.lun == v->lun)) {
654 kref_get(&entry->kref);
655 goto out;
658 entry = NULL;
660 out:
661 spin_unlock_irqrestore(&info->v2p_lock, flags);
662 return entry;
665 static int prepare_pending_reqs(struct vscsibk_info *info,
666 struct vscsiif_request *ring_req,
667 struct vscsibk_pend *pending_req)
669 struct v2p_entry *v2p;
670 struct ids_tuple vir;
672 pending_req->rqid = ring_req->rqid;
673 pending_req->info = info;
675 vir.chn = ring_req->channel;
676 vir.tgt = ring_req->id;
677 vir.lun = ring_req->lun;
679 v2p = scsiback_do_translation(info, &vir);
680 if (!v2p) {
681 pending_req->v2p = NULL;
682 DPRINTK("xen-pvscsi: doesn't exist.\n");
683 return -ENODEV;
685 pending_req->v2p = v2p;
687 /* request range check from frontend */
688 pending_req->sc_data_direction = ring_req->sc_data_direction;
689 if ((pending_req->sc_data_direction != DMA_BIDIRECTIONAL) &&
690 (pending_req->sc_data_direction != DMA_TO_DEVICE) &&
691 (pending_req->sc_data_direction != DMA_FROM_DEVICE) &&
692 (pending_req->sc_data_direction != DMA_NONE)) {
693 DPRINTK("xen-pvscsi: invalid parameter data_dir = %d\n",
694 pending_req->sc_data_direction);
695 return -EINVAL;
698 pending_req->cmd_len = ring_req->cmd_len;
699 if (pending_req->cmd_len > VSCSIIF_MAX_COMMAND_SIZE) {
700 DPRINTK("xen-pvscsi: invalid parameter cmd_len = %d\n",
701 pending_req->cmd_len);
702 return -EINVAL;
704 memcpy(pending_req->cmnd, ring_req->cmnd, pending_req->cmd_len);
706 return 0;
709 static int scsiback_do_cmd_fn(struct vscsibk_info *info)
711 struct vscsiif_back_ring *ring = &info->ring;
712 struct vscsiif_request ring_req;
713 struct vscsibk_pend *pending_req;
714 RING_IDX rc, rp;
715 int err, more_to_do;
716 uint32_t result;
718 rc = ring->req_cons;
719 rp = ring->sring->req_prod;
720 rmb(); /* guest system is accessing ring, too */
722 if (RING_REQUEST_PROD_OVERFLOW(ring, rp)) {
723 rc = ring->rsp_prod_pvt;
724 pr_warn("xen-pvscsi: Dom%d provided bogus ring requests (%#x - %#x = %u). Halting ring processing\n",
725 info->domid, rp, rc, rp - rc);
726 info->ring_error = 1;
727 return 0;
730 while ((rc != rp)) {
731 if (RING_REQUEST_CONS_OVERFLOW(ring, rc))
732 break;
733 pending_req = kmem_cache_alloc(scsiback_cachep, GFP_KERNEL);
734 if (!pending_req)
735 return 1;
737 ring_req = *RING_GET_REQUEST(ring, rc);
738 ring->req_cons = ++rc;
740 err = prepare_pending_reqs(info, &ring_req, pending_req);
741 if (err) {
742 switch (err) {
743 case -ENODEV:
744 result = DID_NO_CONNECT;
745 break;
746 default:
747 result = DRIVER_ERROR;
748 break;
750 scsiback_do_resp_with_sense(NULL, result << 24, 0,
751 pending_req);
752 kmem_cache_free(scsiback_cachep, pending_req);
753 return 1;
756 switch (ring_req.act) {
757 case VSCSIIF_ACT_SCSI_CDB:
758 if (scsiback_gnttab_data_map(&ring_req, pending_req)) {
759 scsiback_fast_flush_area(pending_req);
760 scsiback_do_resp_with_sense(NULL,
761 DRIVER_ERROR << 24, 0, pending_req);
762 kmem_cache_free(scsiback_cachep, pending_req);
763 } else {
764 scsiback_cmd_exec(pending_req);
766 break;
767 case VSCSIIF_ACT_SCSI_ABORT:
768 scsiback_device_action(pending_req, TMR_ABORT_TASK,
769 ring_req.ref_rqid);
770 break;
771 case VSCSIIF_ACT_SCSI_RESET:
772 scsiback_device_action(pending_req, TMR_LUN_RESET, 0);
773 break;
774 default:
775 pr_err_ratelimited("xen-pvscsi: invalid request\n");
776 scsiback_do_resp_with_sense(NULL, DRIVER_ERROR << 24,
777 0, pending_req);
778 kmem_cache_free(scsiback_cachep, pending_req);
779 break;
782 /* Yield point for this unbounded loop. */
783 cond_resched();
786 RING_FINAL_CHECK_FOR_REQUESTS(&info->ring, more_to_do);
787 return more_to_do;
790 static irqreturn_t scsiback_irq_fn(int irq, void *dev_id)
792 struct vscsibk_info *info = dev_id;
794 if (info->ring_error)
795 return IRQ_HANDLED;
797 while (scsiback_do_cmd_fn(info))
798 cond_resched();
800 return IRQ_HANDLED;
803 static int scsiback_init_sring(struct vscsibk_info *info, grant_ref_t ring_ref,
804 evtchn_port_t evtchn)
806 void *area;
807 struct vscsiif_sring *sring;
808 int err;
810 if (info->irq)
811 return -1;
813 err = xenbus_map_ring_valloc(info->dev, ring_ref, &area);
814 if (err)
815 return err;
817 sring = (struct vscsiif_sring *)area;
818 BACK_RING_INIT(&info->ring, sring, PAGE_SIZE);
820 err = bind_interdomain_evtchn_to_irq(info->domid, evtchn);
821 if (err < 0)
822 goto unmap_page;
824 info->irq = err;
826 err = request_threaded_irq(info->irq, NULL, scsiback_irq_fn,
827 IRQF_ONESHOT, "vscsiif-backend", info);
828 if (err)
829 goto free_irq;
831 return 0;
833 free_irq:
834 unbind_from_irqhandler(info->irq, info);
835 info->irq = 0;
836 unmap_page:
837 xenbus_unmap_ring_vfree(info->dev, area);
839 return err;
842 static int scsiback_map(struct vscsibk_info *info)
844 struct xenbus_device *dev = info->dev;
845 unsigned int ring_ref, evtchn;
846 int err;
848 err = xenbus_gather(XBT_NIL, dev->otherend,
849 "ring-ref", "%u", &ring_ref,
850 "event-channel", "%u", &evtchn, NULL);
851 if (err) {
852 xenbus_dev_fatal(dev, err, "reading %s ring", dev->otherend);
853 return err;
856 return scsiback_init_sring(info, ring_ref, evtchn);
860 Add a new translation entry
862 static int scsiback_add_translation_entry(struct vscsibk_info *info,
863 char *phy, struct ids_tuple *v)
865 int err = 0;
866 struct v2p_entry *entry;
867 struct v2p_entry *new;
868 struct list_head *head = &(info->v2p_entry_lists);
869 unsigned long flags;
870 char *lunp;
871 unsigned int lun;
872 struct scsiback_tpg *tpg_entry, *tpg = NULL;
873 char *error = "doesn't exist";
875 lunp = strrchr(phy, ':');
876 if (!lunp) {
877 pr_err("xen-pvscsi: illegal format of physical device %s\n",
878 phy);
879 return -EINVAL;
881 *lunp = 0;
882 lunp++;
883 if (kstrtouint(lunp, 10, &lun) || lun >= TRANSPORT_MAX_LUNS_PER_TPG) {
884 pr_err("xen-pvscsi: lun number not valid: %s\n", lunp);
885 return -EINVAL;
888 mutex_lock(&scsiback_mutex);
889 list_for_each_entry(tpg_entry, &scsiback_list, tv_tpg_list) {
890 if (!strcmp(phy, tpg_entry->tport->tport_name) ||
891 !strcmp(phy, tpg_entry->param_alias)) {
892 spin_lock(&tpg_entry->se_tpg.tpg_lun_lock);
893 if (tpg_entry->se_tpg.tpg_lun_list[lun]->lun_status ==
894 TRANSPORT_LUN_STATUS_ACTIVE) {
895 if (!tpg_entry->tpg_nexus)
896 error = "nexus undefined";
897 else
898 tpg = tpg_entry;
900 spin_unlock(&tpg_entry->se_tpg.tpg_lun_lock);
901 break;
904 if (tpg) {
905 mutex_lock(&tpg->tv_tpg_mutex);
906 tpg->tv_tpg_fe_count++;
907 mutex_unlock(&tpg->tv_tpg_mutex);
909 mutex_unlock(&scsiback_mutex);
911 if (!tpg) {
912 pr_err("xen-pvscsi: %s:%d %s\n", phy, lun, error);
913 return -ENODEV;
916 new = kmalloc(sizeof(struct v2p_entry), GFP_KERNEL);
917 if (new == NULL) {
918 err = -ENOMEM;
919 goto out_free;
922 spin_lock_irqsave(&info->v2p_lock, flags);
924 /* Check double assignment to identical virtual ID */
925 list_for_each_entry(entry, head, l) {
926 if ((entry->v.chn == v->chn) &&
927 (entry->v.tgt == v->tgt) &&
928 (entry->v.lun == v->lun)) {
929 pr_warn("xen-pvscsi: Virtual ID is already used. Assignment was not performed.\n");
930 err = -EEXIST;
931 goto out;
936 /* Create a new translation entry and add to the list */
937 kref_init(&new->kref);
938 new->v = *v;
939 new->tpg = tpg;
940 new->lun = lun;
941 list_add_tail(&new->l, head);
943 out:
944 spin_unlock_irqrestore(&info->v2p_lock, flags);
946 out_free:
947 mutex_lock(&tpg->tv_tpg_mutex);
948 tpg->tv_tpg_fe_count--;
949 mutex_unlock(&tpg->tv_tpg_mutex);
951 if (err)
952 kfree(new);
954 return err;
957 static void __scsiback_del_translation_entry(struct v2p_entry *entry)
959 list_del(&entry->l);
960 kref_put(&entry->kref, scsiback_free_translation_entry);
964 Delete the translation entry specfied
966 static int scsiback_del_translation_entry(struct vscsibk_info *info,
967 struct ids_tuple *v)
969 struct v2p_entry *entry;
970 struct list_head *head = &(info->v2p_entry_lists);
971 unsigned long flags;
973 spin_lock_irqsave(&info->v2p_lock, flags);
974 /* Find out the translation entry specified */
975 list_for_each_entry(entry, head, l) {
976 if ((entry->v.chn == v->chn) &&
977 (entry->v.tgt == v->tgt) &&
978 (entry->v.lun == v->lun)) {
979 goto found;
983 spin_unlock_irqrestore(&info->v2p_lock, flags);
984 return 1;
986 found:
987 /* Delete the translation entry specfied */
988 __scsiback_del_translation_entry(entry);
990 spin_unlock_irqrestore(&info->v2p_lock, flags);
991 return 0;
994 static void scsiback_do_add_lun(struct vscsibk_info *info, const char *state,
995 char *phy, struct ids_tuple *vir)
997 if (!scsiback_add_translation_entry(info, phy, vir)) {
998 if (xenbus_printf(XBT_NIL, info->dev->nodename, state,
999 "%d", XenbusStateInitialised)) {
1000 pr_err("xen-pvscsi: xenbus_printf error %s\n", state);
1001 scsiback_del_translation_entry(info, vir);
1003 } else {
1004 xenbus_printf(XBT_NIL, info->dev->nodename, state,
1005 "%d", XenbusStateClosed);
1009 static void scsiback_do_del_lun(struct vscsibk_info *info, const char *state,
1010 struct ids_tuple *vir)
1012 if (!scsiback_del_translation_entry(info, vir)) {
1013 if (xenbus_printf(XBT_NIL, info->dev->nodename, state,
1014 "%d", XenbusStateClosed))
1015 pr_err("xen-pvscsi: xenbus_printf error %s\n", state);
1019 #define VSCSIBACK_OP_ADD_OR_DEL_LUN 1
1020 #define VSCSIBACK_OP_UPDATEDEV_STATE 2
1022 static void scsiback_do_1lun_hotplug(struct vscsibk_info *info, int op,
1023 char *ent)
1025 int err;
1026 struct ids_tuple vir;
1027 char *val;
1028 int device_state;
1029 char phy[VSCSI_NAMELEN];
1030 char str[64];
1031 char state[64];
1032 struct xenbus_device *dev = info->dev;
1034 /* read status */
1035 snprintf(state, sizeof(state), "vscsi-devs/%s/state", ent);
1036 err = xenbus_scanf(XBT_NIL, dev->nodename, state, "%u", &device_state);
1037 if (XENBUS_EXIST_ERR(err))
1038 return;
1040 /* physical SCSI device */
1041 snprintf(str, sizeof(str), "vscsi-devs/%s/p-dev", ent);
1042 val = xenbus_read(XBT_NIL, dev->nodename, str, NULL);
1043 if (IS_ERR(val)) {
1044 xenbus_printf(XBT_NIL, dev->nodename, state,
1045 "%d", XenbusStateClosed);
1046 return;
1048 strlcpy(phy, val, VSCSI_NAMELEN);
1049 kfree(val);
1051 /* virtual SCSI device */
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 xenbus_printf(XBT_NIL, dev->nodename, state,
1057 "%d", XenbusStateClosed);
1058 return;
1061 switch (op) {
1062 case VSCSIBACK_OP_ADD_OR_DEL_LUN:
1063 if (device_state == XenbusStateInitialising)
1064 scsiback_do_add_lun(info, state, phy, &vir);
1065 if (device_state == XenbusStateClosing)
1066 scsiback_do_del_lun(info, state, &vir);
1067 break;
1069 case VSCSIBACK_OP_UPDATEDEV_STATE:
1070 if (device_state == XenbusStateInitialised) {
1071 /* modify vscsi-devs/dev-x/state */
1072 if (xenbus_printf(XBT_NIL, dev->nodename, state,
1073 "%d", XenbusStateConnected)) {
1074 pr_err("xen-pvscsi: xenbus_printf error %s\n",
1075 str);
1076 scsiback_del_translation_entry(info, &vir);
1077 xenbus_printf(XBT_NIL, dev->nodename, state,
1078 "%d", XenbusStateClosed);
1081 break;
1082 /*When it is necessary, processing is added here.*/
1083 default:
1084 break;
1088 static void scsiback_do_lun_hotplug(struct vscsibk_info *info, int op)
1090 int i;
1091 char **dir;
1092 unsigned int ndir = 0;
1094 dir = xenbus_directory(XBT_NIL, info->dev->nodename, "vscsi-devs",
1095 &ndir);
1096 if (IS_ERR(dir))
1097 return;
1099 for (i = 0; i < ndir; i++)
1100 scsiback_do_1lun_hotplug(info, op, dir[i]);
1102 kfree(dir);
1105 static void scsiback_frontend_changed(struct xenbus_device *dev,
1106 enum xenbus_state frontend_state)
1108 struct vscsibk_info *info = dev_get_drvdata(&dev->dev);
1110 switch (frontend_state) {
1111 case XenbusStateInitialising:
1112 break;
1114 case XenbusStateInitialised:
1115 if (scsiback_map(info))
1116 break;
1118 scsiback_do_lun_hotplug(info, VSCSIBACK_OP_ADD_OR_DEL_LUN);
1119 xenbus_switch_state(dev, XenbusStateConnected);
1120 break;
1122 case XenbusStateConnected:
1123 scsiback_do_lun_hotplug(info, VSCSIBACK_OP_UPDATEDEV_STATE);
1125 if (dev->state == XenbusStateConnected)
1126 break;
1128 xenbus_switch_state(dev, XenbusStateConnected);
1129 break;
1131 case XenbusStateClosing:
1132 if (info->irq)
1133 scsiback_disconnect(info);
1135 xenbus_switch_state(dev, XenbusStateClosing);
1136 break;
1138 case XenbusStateClosed:
1139 xenbus_switch_state(dev, XenbusStateClosed);
1140 if (xenbus_dev_is_online(dev))
1141 break;
1142 /* fall through if not online */
1143 case XenbusStateUnknown:
1144 device_unregister(&dev->dev);
1145 break;
1147 case XenbusStateReconfiguring:
1148 scsiback_do_lun_hotplug(info, VSCSIBACK_OP_ADD_OR_DEL_LUN);
1149 xenbus_switch_state(dev, XenbusStateReconfigured);
1151 break;
1153 default:
1154 xenbus_dev_fatal(dev, -EINVAL, "saw state %d at frontend",
1155 frontend_state);
1156 break;
1161 Release the translation entry specfied
1163 static void scsiback_release_translation_entry(struct vscsibk_info *info)
1165 struct v2p_entry *entry, *tmp;
1166 struct list_head *head = &(info->v2p_entry_lists);
1167 unsigned long flags;
1169 spin_lock_irqsave(&info->v2p_lock, flags);
1171 list_for_each_entry_safe(entry, tmp, head, l)
1172 __scsiback_del_translation_entry(entry);
1174 spin_unlock_irqrestore(&info->v2p_lock, flags);
1177 static int scsiback_remove(struct xenbus_device *dev)
1179 struct vscsibk_info *info = dev_get_drvdata(&dev->dev);
1181 if (info->irq)
1182 scsiback_disconnect(info);
1184 scsiback_release_translation_entry(info);
1186 dev_set_drvdata(&dev->dev, NULL);
1188 return 0;
1191 static int scsiback_probe(struct xenbus_device *dev,
1192 const struct xenbus_device_id *id)
1194 int err;
1196 struct vscsibk_info *info = kzalloc(sizeof(struct vscsibk_info),
1197 GFP_KERNEL);
1199 DPRINTK("%p %d\n", dev, dev->otherend_id);
1201 if (!info) {
1202 xenbus_dev_fatal(dev, -ENOMEM, "allocating backend structure");
1203 return -ENOMEM;
1205 info->dev = dev;
1206 dev_set_drvdata(&dev->dev, info);
1208 info->domid = dev->otherend_id;
1209 spin_lock_init(&info->ring_lock);
1210 info->ring_error = 0;
1211 atomic_set(&info->nr_unreplied_reqs, 0);
1212 init_waitqueue_head(&info->waiting_to_free);
1213 info->dev = dev;
1214 info->irq = 0;
1215 INIT_LIST_HEAD(&info->v2p_entry_lists);
1216 spin_lock_init(&info->v2p_lock);
1218 err = xenbus_printf(XBT_NIL, dev->nodename, "feature-sg-grant", "%u",
1219 SG_ALL);
1220 if (err)
1221 xenbus_dev_error(dev, err, "writing feature-sg-grant");
1223 err = xenbus_switch_state(dev, XenbusStateInitWait);
1224 if (err)
1225 goto fail;
1227 return 0;
1229 fail:
1230 pr_warn("xen-pvscsi: %s failed\n", __func__);
1231 scsiback_remove(dev);
1233 return err;
1236 static char *scsiback_dump_proto_id(struct scsiback_tport *tport)
1238 switch (tport->tport_proto_id) {
1239 case SCSI_PROTOCOL_SAS:
1240 return "SAS";
1241 case SCSI_PROTOCOL_FCP:
1242 return "FCP";
1243 case SCSI_PROTOCOL_ISCSI:
1244 return "iSCSI";
1245 default:
1246 break;
1249 return "Unknown";
1252 static u8 scsiback_get_fabric_proto_ident(struct se_portal_group *se_tpg)
1254 struct scsiback_tpg *tpg = container_of(se_tpg,
1255 struct scsiback_tpg, se_tpg);
1256 struct scsiback_tport *tport = tpg->tport;
1258 switch (tport->tport_proto_id) {
1259 case SCSI_PROTOCOL_SAS:
1260 return sas_get_fabric_proto_ident(se_tpg);
1261 case SCSI_PROTOCOL_FCP:
1262 return fc_get_fabric_proto_ident(se_tpg);
1263 case SCSI_PROTOCOL_ISCSI:
1264 return iscsi_get_fabric_proto_ident(se_tpg);
1265 default:
1266 pr_err("Unknown tport_proto_id: 0x%02x, using SAS emulation\n",
1267 tport->tport_proto_id);
1268 break;
1271 return sas_get_fabric_proto_ident(se_tpg);
1274 static char *scsiback_get_fabric_wwn(struct se_portal_group *se_tpg)
1276 struct scsiback_tpg *tpg = container_of(se_tpg,
1277 struct scsiback_tpg, se_tpg);
1278 struct scsiback_tport *tport = tpg->tport;
1280 return &tport->tport_name[0];
1283 static u16 scsiback_get_tag(struct se_portal_group *se_tpg)
1285 struct scsiback_tpg *tpg = container_of(se_tpg,
1286 struct scsiback_tpg, se_tpg);
1287 return tpg->tport_tpgt;
1290 static u32 scsiback_get_default_depth(struct se_portal_group *se_tpg)
1292 return 1;
1295 static u32
1296 scsiback_get_pr_transport_id(struct se_portal_group *se_tpg,
1297 struct se_node_acl *se_nacl,
1298 struct t10_pr_registration *pr_reg,
1299 int *format_code,
1300 unsigned char *buf)
1302 struct scsiback_tpg *tpg = container_of(se_tpg,
1303 struct scsiback_tpg, se_tpg);
1304 struct scsiback_tport *tport = tpg->tport;
1306 switch (tport->tport_proto_id) {
1307 case SCSI_PROTOCOL_SAS:
1308 return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
1309 format_code, buf);
1310 case SCSI_PROTOCOL_FCP:
1311 return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
1312 format_code, buf);
1313 case SCSI_PROTOCOL_ISCSI:
1314 return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
1315 format_code, buf);
1316 default:
1317 pr_err("Unknown tport_proto_id: 0x%02x, using SAS emulation\n",
1318 tport->tport_proto_id);
1319 break;
1322 return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
1323 format_code, buf);
1326 static u32
1327 scsiback_get_pr_transport_id_len(struct se_portal_group *se_tpg,
1328 struct se_node_acl *se_nacl,
1329 struct t10_pr_registration *pr_reg,
1330 int *format_code)
1332 struct scsiback_tpg *tpg = container_of(se_tpg,
1333 struct scsiback_tpg, se_tpg);
1334 struct scsiback_tport *tport = tpg->tport;
1336 switch (tport->tport_proto_id) {
1337 case SCSI_PROTOCOL_SAS:
1338 return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
1339 format_code);
1340 case SCSI_PROTOCOL_FCP:
1341 return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
1342 format_code);
1343 case SCSI_PROTOCOL_ISCSI:
1344 return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
1345 format_code);
1346 default:
1347 pr_err("Unknown tport_proto_id: 0x%02x, using SAS emulation\n",
1348 tport->tport_proto_id);
1349 break;
1352 return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
1353 format_code);
1356 static char *
1357 scsiback_parse_pr_out_transport_id(struct se_portal_group *se_tpg,
1358 const char *buf,
1359 u32 *out_tid_len,
1360 char **port_nexus_ptr)
1362 struct scsiback_tpg *tpg = container_of(se_tpg,
1363 struct scsiback_tpg, se_tpg);
1364 struct scsiback_tport *tport = tpg->tport;
1366 switch (tport->tport_proto_id) {
1367 case SCSI_PROTOCOL_SAS:
1368 return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
1369 port_nexus_ptr);
1370 case SCSI_PROTOCOL_FCP:
1371 return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
1372 port_nexus_ptr);
1373 case SCSI_PROTOCOL_ISCSI:
1374 return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
1375 port_nexus_ptr);
1376 default:
1377 pr_err("Unknown tport_proto_id: 0x%02x, using SAS emulation\n",
1378 tport->tport_proto_id);
1379 break;
1382 return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
1383 port_nexus_ptr);
1386 static struct se_wwn *
1387 scsiback_make_tport(struct target_fabric_configfs *tf,
1388 struct config_group *group,
1389 const char *name)
1391 struct scsiback_tport *tport;
1392 char *ptr;
1393 u64 wwpn = 0;
1394 int off = 0;
1396 tport = kzalloc(sizeof(struct scsiback_tport), GFP_KERNEL);
1397 if (!tport)
1398 return ERR_PTR(-ENOMEM);
1400 tport->tport_wwpn = wwpn;
1402 * Determine the emulated Protocol Identifier and Target Port Name
1403 * based on the incoming configfs directory name.
1405 ptr = strstr(name, "naa.");
1406 if (ptr) {
1407 tport->tport_proto_id = SCSI_PROTOCOL_SAS;
1408 goto check_len;
1410 ptr = strstr(name, "fc.");
1411 if (ptr) {
1412 tport->tport_proto_id = SCSI_PROTOCOL_FCP;
1413 off = 3; /* Skip over "fc." */
1414 goto check_len;
1416 ptr = strstr(name, "iqn.");
1417 if (ptr) {
1418 tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
1419 goto check_len;
1422 pr_err("Unable to locate prefix for emulated Target Port: %s\n", name);
1423 kfree(tport);
1424 return ERR_PTR(-EINVAL);
1426 check_len:
1427 if (strlen(name) >= VSCSI_NAMELEN) {
1428 pr_err("Emulated %s Address: %s, exceeds max: %d\n", name,
1429 scsiback_dump_proto_id(tport), VSCSI_NAMELEN);
1430 kfree(tport);
1431 return ERR_PTR(-EINVAL);
1433 snprintf(&tport->tport_name[0], VSCSI_NAMELEN, "%s", &name[off]);
1435 pr_debug("xen-pvscsi: Allocated emulated Target %s Address: %s\n",
1436 scsiback_dump_proto_id(tport), name);
1438 return &tport->tport_wwn;
1441 static void scsiback_drop_tport(struct se_wwn *wwn)
1443 struct scsiback_tport *tport = container_of(wwn,
1444 struct scsiback_tport, tport_wwn);
1446 pr_debug("xen-pvscsi: Deallocating emulated Target %s Address: %s\n",
1447 scsiback_dump_proto_id(tport), tport->tport_name);
1449 kfree(tport);
1452 static struct se_node_acl *
1453 scsiback_alloc_fabric_acl(struct se_portal_group *se_tpg)
1455 return kzalloc(sizeof(struct se_node_acl), GFP_KERNEL);
1458 static void
1459 scsiback_release_fabric_acl(struct se_portal_group *se_tpg,
1460 struct se_node_acl *se_nacl)
1462 kfree(se_nacl);
1465 static u32 scsiback_tpg_get_inst_index(struct se_portal_group *se_tpg)
1467 return 1;
1470 static int scsiback_check_stop_free(struct se_cmd *se_cmd)
1473 * Do not release struct se_cmd's containing a valid TMR
1474 * pointer. These will be released directly in scsiback_device_action()
1475 * with transport_generic_free_cmd().
1477 if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
1478 return 0;
1480 transport_generic_free_cmd(se_cmd, 0);
1481 return 1;
1484 static void scsiback_release_cmd(struct se_cmd *se_cmd)
1486 struct vscsibk_pend *pending_req = container_of(se_cmd,
1487 struct vscsibk_pend, se_cmd);
1489 kmem_cache_free(scsiback_cachep, pending_req);
1492 static int scsiback_shutdown_session(struct se_session *se_sess)
1494 return 0;
1497 static void scsiback_close_session(struct se_session *se_sess)
1501 static u32 scsiback_sess_get_index(struct se_session *se_sess)
1503 return 0;
1506 static int scsiback_write_pending(struct se_cmd *se_cmd)
1508 /* Go ahead and process the write immediately */
1509 target_execute_cmd(se_cmd);
1511 return 0;
1514 static int scsiback_write_pending_status(struct se_cmd *se_cmd)
1516 return 0;
1519 static void scsiback_set_default_node_attrs(struct se_node_acl *nacl)
1523 static u32 scsiback_get_task_tag(struct se_cmd *se_cmd)
1525 struct vscsibk_pend *pending_req = container_of(se_cmd,
1526 struct vscsibk_pend, se_cmd);
1528 return pending_req->rqid;
1531 static int scsiback_get_cmd_state(struct se_cmd *se_cmd)
1533 return 0;
1536 static int scsiback_queue_data_in(struct se_cmd *se_cmd)
1538 struct vscsibk_pend *pending_req = container_of(se_cmd,
1539 struct vscsibk_pend, se_cmd);
1541 pending_req->result = SAM_STAT_GOOD;
1542 scsiback_cmd_done(pending_req);
1543 return 0;
1546 static int scsiback_queue_status(struct se_cmd *se_cmd)
1548 struct vscsibk_pend *pending_req = container_of(se_cmd,
1549 struct vscsibk_pend, se_cmd);
1551 if (se_cmd->sense_buffer &&
1552 ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
1553 (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE)))
1554 pending_req->result = (DRIVER_SENSE << 24) |
1555 SAM_STAT_CHECK_CONDITION;
1556 else
1557 pending_req->result = se_cmd->scsi_status;
1559 scsiback_cmd_done(pending_req);
1560 return 0;
1563 static void scsiback_queue_tm_rsp(struct se_cmd *se_cmd)
1565 struct se_tmr_req *se_tmr = se_cmd->se_tmr_req;
1566 struct scsiback_tmr *tmr = se_tmr->fabric_tmr_ptr;
1568 atomic_set(&tmr->tmr_complete, 1);
1569 wake_up(&tmr->tmr_wait);
1572 static void scsiback_aborted_task(struct se_cmd *se_cmd)
1576 static ssize_t scsiback_tpg_param_show_alias(struct se_portal_group *se_tpg,
1577 char *page)
1579 struct scsiback_tpg *tpg = container_of(se_tpg, struct scsiback_tpg,
1580 se_tpg);
1581 ssize_t rb;
1583 mutex_lock(&tpg->tv_tpg_mutex);
1584 rb = snprintf(page, PAGE_SIZE, "%s\n", tpg->param_alias);
1585 mutex_unlock(&tpg->tv_tpg_mutex);
1587 return rb;
1590 static ssize_t scsiback_tpg_param_store_alias(struct se_portal_group *se_tpg,
1591 const char *page, size_t count)
1593 struct scsiback_tpg *tpg = container_of(se_tpg, struct scsiback_tpg,
1594 se_tpg);
1595 int len;
1597 if (strlen(page) >= VSCSI_NAMELEN) {
1598 pr_err("param alias: %s, exceeds max: %d\n", page,
1599 VSCSI_NAMELEN);
1600 return -EINVAL;
1603 mutex_lock(&tpg->tv_tpg_mutex);
1604 len = snprintf(tpg->param_alias, VSCSI_NAMELEN, "%s", page);
1605 if (tpg->param_alias[len - 1] == '\n')
1606 tpg->param_alias[len - 1] = '\0';
1607 mutex_unlock(&tpg->tv_tpg_mutex);
1609 return count;
1612 TF_TPG_PARAM_ATTR(scsiback, alias, S_IRUGO | S_IWUSR);
1614 static struct configfs_attribute *scsiback_param_attrs[] = {
1615 &scsiback_tpg_param_alias.attr,
1616 NULL,
1619 static int scsiback_make_nexus(struct scsiback_tpg *tpg,
1620 const char *name)
1622 struct se_portal_group *se_tpg;
1623 struct se_session *se_sess;
1624 struct scsiback_nexus *tv_nexus;
1626 mutex_lock(&tpg->tv_tpg_mutex);
1627 if (tpg->tpg_nexus) {
1628 mutex_unlock(&tpg->tv_tpg_mutex);
1629 pr_debug("tpg->tpg_nexus already exists\n");
1630 return -EEXIST;
1632 se_tpg = &tpg->se_tpg;
1634 tv_nexus = kzalloc(sizeof(struct scsiback_nexus), GFP_KERNEL);
1635 if (!tv_nexus) {
1636 mutex_unlock(&tpg->tv_tpg_mutex);
1637 return -ENOMEM;
1640 * Initialize the struct se_session pointer
1642 tv_nexus->tvn_se_sess = transport_init_session(TARGET_PROT_NORMAL);
1643 if (IS_ERR(tv_nexus->tvn_se_sess)) {
1644 mutex_unlock(&tpg->tv_tpg_mutex);
1645 kfree(tv_nexus);
1646 return -ENOMEM;
1648 se_sess = tv_nexus->tvn_se_sess;
1650 * Since we are running in 'demo mode' this call with generate a
1651 * struct se_node_acl for the scsiback struct se_portal_group with
1652 * the SCSI Initiator port name of the passed configfs group 'name'.
1654 tv_nexus->tvn_se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
1655 se_tpg, (unsigned char *)name);
1656 if (!tv_nexus->tvn_se_sess->se_node_acl) {
1657 mutex_unlock(&tpg->tv_tpg_mutex);
1658 pr_debug("core_tpg_check_initiator_node_acl() failed for %s\n",
1659 name);
1660 goto out;
1663 * Now register the TCM pvscsi virtual I_T Nexus as active with the
1664 * call to __transport_register_session()
1666 __transport_register_session(se_tpg, tv_nexus->tvn_se_sess->se_node_acl,
1667 tv_nexus->tvn_se_sess, tv_nexus);
1668 tpg->tpg_nexus = tv_nexus;
1670 mutex_unlock(&tpg->tv_tpg_mutex);
1671 return 0;
1673 out:
1674 transport_free_session(se_sess);
1675 kfree(tv_nexus);
1676 return -ENOMEM;
1679 static int scsiback_drop_nexus(struct scsiback_tpg *tpg)
1681 struct se_session *se_sess;
1682 struct scsiback_nexus *tv_nexus;
1684 mutex_lock(&tpg->tv_tpg_mutex);
1685 tv_nexus = tpg->tpg_nexus;
1686 if (!tv_nexus) {
1687 mutex_unlock(&tpg->tv_tpg_mutex);
1688 return -ENODEV;
1691 se_sess = tv_nexus->tvn_se_sess;
1692 if (!se_sess) {
1693 mutex_unlock(&tpg->tv_tpg_mutex);
1694 return -ENODEV;
1697 if (tpg->tv_tpg_port_count != 0) {
1698 mutex_unlock(&tpg->tv_tpg_mutex);
1699 pr_err("Unable to remove xen-pvscsi I_T Nexus with active TPG port count: %d\n",
1700 tpg->tv_tpg_port_count);
1701 return -EBUSY;
1704 if (tpg->tv_tpg_fe_count != 0) {
1705 mutex_unlock(&tpg->tv_tpg_mutex);
1706 pr_err("Unable to remove xen-pvscsi I_T Nexus with active TPG frontend count: %d\n",
1707 tpg->tv_tpg_fe_count);
1708 return -EBUSY;
1711 pr_debug("xen-pvscsi: Removing I_T Nexus to emulated %s Initiator Port: %s\n",
1712 scsiback_dump_proto_id(tpg->tport),
1713 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1716 * Release the SCSI I_T Nexus to the emulated xen-pvscsi Target Port
1718 transport_deregister_session(tv_nexus->tvn_se_sess);
1719 tpg->tpg_nexus = NULL;
1720 mutex_unlock(&tpg->tv_tpg_mutex);
1722 kfree(tv_nexus);
1723 return 0;
1726 static ssize_t scsiback_tpg_show_nexus(struct se_portal_group *se_tpg,
1727 char *page)
1729 struct scsiback_tpg *tpg = container_of(se_tpg,
1730 struct scsiback_tpg, se_tpg);
1731 struct scsiback_nexus *tv_nexus;
1732 ssize_t ret;
1734 mutex_lock(&tpg->tv_tpg_mutex);
1735 tv_nexus = tpg->tpg_nexus;
1736 if (!tv_nexus) {
1737 mutex_unlock(&tpg->tv_tpg_mutex);
1738 return -ENODEV;
1740 ret = snprintf(page, PAGE_SIZE, "%s\n",
1741 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1742 mutex_unlock(&tpg->tv_tpg_mutex);
1744 return ret;
1747 static ssize_t scsiback_tpg_store_nexus(struct se_portal_group *se_tpg,
1748 const char *page,
1749 size_t count)
1751 struct scsiback_tpg *tpg = container_of(se_tpg,
1752 struct scsiback_tpg, se_tpg);
1753 struct scsiback_tport *tport_wwn = tpg->tport;
1754 unsigned char i_port[VSCSI_NAMELEN], *ptr, *port_ptr;
1755 int ret;
1757 * Shutdown the active I_T nexus if 'NULL' is passed..
1759 if (!strncmp(page, "NULL", 4)) {
1760 ret = scsiback_drop_nexus(tpg);
1761 return (!ret) ? count : ret;
1764 * Otherwise make sure the passed virtual Initiator port WWN matches
1765 * the fabric protocol_id set in scsiback_make_tport(), and call
1766 * scsiback_make_nexus().
1768 if (strlen(page) >= VSCSI_NAMELEN) {
1769 pr_err("Emulated NAA Sas Address: %s, exceeds max: %d\n",
1770 page, VSCSI_NAMELEN);
1771 return -EINVAL;
1773 snprintf(&i_port[0], VSCSI_NAMELEN, "%s", page);
1775 ptr = strstr(i_port, "naa.");
1776 if (ptr) {
1777 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
1778 pr_err("Passed SAS Initiator Port %s does not match target port protoid: %s\n",
1779 i_port, scsiback_dump_proto_id(tport_wwn));
1780 return -EINVAL;
1782 port_ptr = &i_port[0];
1783 goto check_newline;
1785 ptr = strstr(i_port, "fc.");
1786 if (ptr) {
1787 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
1788 pr_err("Passed FCP Initiator Port %s does not match target port protoid: %s\n",
1789 i_port, scsiback_dump_proto_id(tport_wwn));
1790 return -EINVAL;
1792 port_ptr = &i_port[3]; /* Skip over "fc." */
1793 goto check_newline;
1795 ptr = strstr(i_port, "iqn.");
1796 if (ptr) {
1797 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
1798 pr_err("Passed iSCSI Initiator Port %s does not match target port protoid: %s\n",
1799 i_port, scsiback_dump_proto_id(tport_wwn));
1800 return -EINVAL;
1802 port_ptr = &i_port[0];
1803 goto check_newline;
1805 pr_err("Unable to locate prefix for emulated Initiator Port: %s\n",
1806 i_port);
1807 return -EINVAL;
1809 * Clear any trailing newline for the NAA WWN
1811 check_newline:
1812 if (i_port[strlen(i_port) - 1] == '\n')
1813 i_port[strlen(i_port) - 1] = '\0';
1815 ret = scsiback_make_nexus(tpg, port_ptr);
1816 if (ret < 0)
1817 return ret;
1819 return count;
1822 TF_TPG_BASE_ATTR(scsiback, nexus, S_IRUGO | S_IWUSR);
1824 static struct configfs_attribute *scsiback_tpg_attrs[] = {
1825 &scsiback_tpg_nexus.attr,
1826 NULL,
1829 static ssize_t
1830 scsiback_wwn_show_attr_version(struct target_fabric_configfs *tf,
1831 char *page)
1833 return sprintf(page, "xen-pvscsi fabric module %s on %s/%s on "
1834 UTS_RELEASE"\n",
1835 VSCSI_VERSION, utsname()->sysname, utsname()->machine);
1838 TF_WWN_ATTR_RO(scsiback, version);
1840 static struct configfs_attribute *scsiback_wwn_attrs[] = {
1841 &scsiback_wwn_version.attr,
1842 NULL,
1845 static char *scsiback_get_fabric_name(void)
1847 return "xen-pvscsi";
1850 static int scsiback_port_link(struct se_portal_group *se_tpg,
1851 struct se_lun *lun)
1853 struct scsiback_tpg *tpg = container_of(se_tpg,
1854 struct scsiback_tpg, se_tpg);
1856 mutex_lock(&tpg->tv_tpg_mutex);
1857 tpg->tv_tpg_port_count++;
1858 mutex_unlock(&tpg->tv_tpg_mutex);
1860 return 0;
1863 static void scsiback_port_unlink(struct se_portal_group *se_tpg,
1864 struct se_lun *lun)
1866 struct scsiback_tpg *tpg = container_of(se_tpg,
1867 struct scsiback_tpg, se_tpg);
1869 mutex_lock(&tpg->tv_tpg_mutex);
1870 tpg->tv_tpg_port_count--;
1871 mutex_unlock(&tpg->tv_tpg_mutex);
1874 static struct se_portal_group *
1875 scsiback_make_tpg(struct se_wwn *wwn,
1876 struct config_group *group,
1877 const char *name)
1879 struct scsiback_tport *tport = container_of(wwn,
1880 struct scsiback_tport, tport_wwn);
1882 struct scsiback_tpg *tpg;
1883 u16 tpgt;
1884 int ret;
1886 if (strstr(name, "tpgt_") != name)
1887 return ERR_PTR(-EINVAL);
1888 ret = kstrtou16(name + 5, 10, &tpgt);
1889 if (ret)
1890 return ERR_PTR(ret);
1892 tpg = kzalloc(sizeof(struct scsiback_tpg), GFP_KERNEL);
1893 if (!tpg)
1894 return ERR_PTR(-ENOMEM);
1896 mutex_init(&tpg->tv_tpg_mutex);
1897 INIT_LIST_HEAD(&tpg->tv_tpg_list);
1898 INIT_LIST_HEAD(&tpg->info_list);
1899 tpg->tport = tport;
1900 tpg->tport_tpgt = tpgt;
1902 ret = core_tpg_register(&scsiback_fabric_configfs->tf_ops, wwn,
1903 &tpg->se_tpg, tpg, TRANSPORT_TPG_TYPE_NORMAL);
1904 if (ret < 0) {
1905 kfree(tpg);
1906 return NULL;
1908 mutex_lock(&scsiback_mutex);
1909 list_add_tail(&tpg->tv_tpg_list, &scsiback_list);
1910 mutex_unlock(&scsiback_mutex);
1912 return &tpg->se_tpg;
1915 static void scsiback_drop_tpg(struct se_portal_group *se_tpg)
1917 struct scsiback_tpg *tpg = container_of(se_tpg,
1918 struct scsiback_tpg, se_tpg);
1920 mutex_lock(&scsiback_mutex);
1921 list_del(&tpg->tv_tpg_list);
1922 mutex_unlock(&scsiback_mutex);
1924 * Release the virtual I_T Nexus for this xen-pvscsi TPG
1926 scsiback_drop_nexus(tpg);
1928 * Deregister the se_tpg from TCM..
1930 core_tpg_deregister(se_tpg);
1931 kfree(tpg);
1934 static int scsiback_check_true(struct se_portal_group *se_tpg)
1936 return 1;
1939 static int scsiback_check_false(struct se_portal_group *se_tpg)
1941 return 0;
1944 static struct target_core_fabric_ops scsiback_ops = {
1945 .get_fabric_name = scsiback_get_fabric_name,
1946 .get_fabric_proto_ident = scsiback_get_fabric_proto_ident,
1947 .tpg_get_wwn = scsiback_get_fabric_wwn,
1948 .tpg_get_tag = scsiback_get_tag,
1949 .tpg_get_default_depth = scsiback_get_default_depth,
1950 .tpg_get_pr_transport_id = scsiback_get_pr_transport_id,
1951 .tpg_get_pr_transport_id_len = scsiback_get_pr_transport_id_len,
1952 .tpg_parse_pr_out_transport_id = scsiback_parse_pr_out_transport_id,
1953 .tpg_check_demo_mode = scsiback_check_true,
1954 .tpg_check_demo_mode_cache = scsiback_check_true,
1955 .tpg_check_demo_mode_write_protect = scsiback_check_false,
1956 .tpg_check_prod_mode_write_protect = scsiback_check_false,
1957 .tpg_alloc_fabric_acl = scsiback_alloc_fabric_acl,
1958 .tpg_release_fabric_acl = scsiback_release_fabric_acl,
1959 .tpg_get_inst_index = scsiback_tpg_get_inst_index,
1960 .check_stop_free = scsiback_check_stop_free,
1961 .release_cmd = scsiback_release_cmd,
1962 .put_session = NULL,
1963 .shutdown_session = scsiback_shutdown_session,
1964 .close_session = scsiback_close_session,
1965 .sess_get_index = scsiback_sess_get_index,
1966 .sess_get_initiator_sid = NULL,
1967 .write_pending = scsiback_write_pending,
1968 .write_pending_status = scsiback_write_pending_status,
1969 .set_default_node_attributes = scsiback_set_default_node_attrs,
1970 .get_task_tag = scsiback_get_task_tag,
1971 .get_cmd_state = scsiback_get_cmd_state,
1972 .queue_data_in = scsiback_queue_data_in,
1973 .queue_status = scsiback_queue_status,
1974 .queue_tm_rsp = scsiback_queue_tm_rsp,
1975 .aborted_task = scsiback_aborted_task,
1977 * Setup callers for generic logic in target_core_fabric_configfs.c
1979 .fabric_make_wwn = scsiback_make_tport,
1980 .fabric_drop_wwn = scsiback_drop_tport,
1981 .fabric_make_tpg = scsiback_make_tpg,
1982 .fabric_drop_tpg = scsiback_drop_tpg,
1983 .fabric_post_link = scsiback_port_link,
1984 .fabric_pre_unlink = scsiback_port_unlink,
1985 .fabric_make_np = NULL,
1986 .fabric_drop_np = NULL,
1987 #if 0
1988 .fabric_make_nodeacl = scsiback_make_nodeacl,
1989 .fabric_drop_nodeacl = scsiback_drop_nodeacl,
1990 #endif
1993 static int scsiback_register_configfs(void)
1995 struct target_fabric_configfs *fabric;
1996 int ret;
1998 pr_debug("xen-pvscsi: fabric module %s on %s/%s on "UTS_RELEASE"\n",
1999 VSCSI_VERSION, utsname()->sysname, utsname()->machine);
2001 * Register the top level struct config_item_type with TCM core
2003 fabric = target_fabric_configfs_init(THIS_MODULE, "xen-pvscsi");
2004 if (IS_ERR(fabric))
2005 return PTR_ERR(fabric);
2008 * Setup fabric->tf_ops from our local scsiback_ops
2010 fabric->tf_ops = scsiback_ops;
2012 * Setup default attribute lists for various fabric->tf_cit_tmpl
2014 fabric->tf_cit_tmpl.tfc_wwn_cit.ct_attrs = scsiback_wwn_attrs;
2015 fabric->tf_cit_tmpl.tfc_tpg_base_cit.ct_attrs = scsiback_tpg_attrs;
2016 fabric->tf_cit_tmpl.tfc_tpg_attrib_cit.ct_attrs = NULL;
2017 fabric->tf_cit_tmpl.tfc_tpg_param_cit.ct_attrs = scsiback_param_attrs;
2018 fabric->tf_cit_tmpl.tfc_tpg_np_base_cit.ct_attrs = NULL;
2019 fabric->tf_cit_tmpl.tfc_tpg_nacl_base_cit.ct_attrs = NULL;
2020 fabric->tf_cit_tmpl.tfc_tpg_nacl_attrib_cit.ct_attrs = NULL;
2021 fabric->tf_cit_tmpl.tfc_tpg_nacl_auth_cit.ct_attrs = NULL;
2022 fabric->tf_cit_tmpl.tfc_tpg_nacl_param_cit.ct_attrs = NULL;
2024 * Register the fabric for use within TCM
2026 ret = target_fabric_configfs_register(fabric);
2027 if (ret < 0) {
2028 target_fabric_configfs_free(fabric);
2029 return ret;
2032 * Setup our local pointer to *fabric
2034 scsiback_fabric_configfs = fabric;
2035 pr_debug("xen-pvscsi: Set fabric -> scsiback_fabric_configfs\n");
2036 return 0;
2039 static void scsiback_deregister_configfs(void)
2041 if (!scsiback_fabric_configfs)
2042 return;
2044 target_fabric_configfs_deregister(scsiback_fabric_configfs);
2045 scsiback_fabric_configfs = NULL;
2046 pr_debug("xen-pvscsi: Cleared scsiback_fabric_configfs\n");
2049 static const struct xenbus_device_id scsiback_ids[] = {
2050 { "vscsi" },
2051 { "" }
2054 static struct xenbus_driver scsiback_driver = {
2055 .ids = scsiback_ids,
2056 .probe = scsiback_probe,
2057 .remove = scsiback_remove,
2058 .otherend_changed = scsiback_frontend_changed
2061 static void scsiback_init_pend(void *p)
2063 struct vscsibk_pend *pend = p;
2064 int i;
2066 memset(pend, 0, sizeof(*pend));
2067 for (i = 0; i < VSCSI_MAX_GRANTS; i++)
2068 pend->grant_handles[i] = SCSIBACK_INVALID_HANDLE;
2071 static int __init scsiback_init(void)
2073 int ret;
2075 if (!xen_domain())
2076 return -ENODEV;
2078 scsiback_cachep = kmem_cache_create("vscsiif_cache",
2079 sizeof(struct vscsibk_pend), 0, 0, scsiback_init_pend);
2080 if (!scsiback_cachep)
2081 return -ENOMEM;
2083 ret = xenbus_register_backend(&scsiback_driver);
2084 if (ret)
2085 goto out_cache_destroy;
2087 ret = scsiback_register_configfs();
2088 if (ret)
2089 goto out_unregister_xenbus;
2091 return 0;
2093 out_unregister_xenbus:
2094 xenbus_unregister_driver(&scsiback_driver);
2095 out_cache_destroy:
2096 kmem_cache_destroy(scsiback_cachep);
2097 pr_err("xen-pvscsi: %s: error %d\n", __func__, ret);
2098 return ret;
2101 static void __exit scsiback_exit(void)
2103 struct page *page;
2105 while (free_pages_num) {
2106 if (get_free_page(&page))
2107 BUG();
2108 gnttab_free_pages(1, &page);
2110 scsiback_deregister_configfs();
2111 xenbus_unregister_driver(&scsiback_driver);
2112 kmem_cache_destroy(scsiback_cachep);
2115 module_init(scsiback_init);
2116 module_exit(scsiback_exit);
2118 MODULE_DESCRIPTION("Xen SCSI backend driver");
2119 MODULE_LICENSE("Dual BSD/GPL");
2120 MODULE_ALIAS("xen-backend:vscsi");
2121 MODULE_AUTHOR("Juergen Gross <jgross@suse.com>");