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
34 #define pr_fmt(fmt) "xen-pvscsi: " fmt
38 #include <linux/module.h>
39 #include <linux/utsname.h>
40 #include <linux/interrupt.h>
41 #include <linux/slab.h>
42 #include <linux/wait.h>
43 #include <linux/sched.h>
44 #include <linux/list.h>
45 #include <linux/gfp.h>
46 #include <linux/delay.h>
47 #include <linux/spinlock.h>
48 #include <linux/configfs.h>
50 #include <generated/utsrelease.h>
52 #include <scsi/scsi_host.h> /* SG_ALL */
54 #include <target/target_core_base.h>
55 #include <target/target_core_fabric.h>
57 #include <asm/hypervisor.h>
60 #include <xen/balloon.h>
61 #include <xen/events.h>
62 #include <xen/xenbus.h>
63 #include <xen/grant_table.h>
66 #include <xen/interface/grant_table.h>
67 #include <xen/interface/io/vscsiif.h>
69 #define VSCSI_VERSION "v0.1"
70 #define VSCSI_NAMELEN 32
73 unsigned int hst; /* host */
74 unsigned int chn; /* channel */
75 unsigned int tgt; /* target */
76 unsigned int lun; /* LUN */
80 struct ids_tuple v; /* translate from */
81 struct scsiback_tpg *tpg; /* translate to */
88 struct xenbus_device *dev;
93 struct vscsiif_back_ring ring;
96 atomic_t nr_unreplied_reqs;
99 struct list_head v2p_entry_lists;
101 wait_queue_head_t waiting_to_free;
103 struct gnttab_page_cache free_pages;
106 /* theoretical maximum of grants for one request */
107 #define VSCSI_MAX_GRANTS (SG_ALL + VSCSIIF_SG_TABLESIZE)
110 * VSCSI_GRANT_BATCH is the maximum number of grants to be processed in one
111 * call to map/unmap grants. Don't choose it too large, as there are arrays
112 * with VSCSI_GRANT_BATCH elements allocated on the stack.
114 #define VSCSI_GRANT_BATCH 16
116 struct vscsibk_pend {
119 uint8_t cmnd[VSCSIIF_MAX_COMMAND_SIZE];
122 uint8_t sc_data_direction;
123 uint16_t n_sg; /* real length of SG list */
124 uint16_t n_grants; /* SG pages and potentially SG list */
128 struct vscsibk_info *info;
129 struct v2p_entry *v2p;
130 struct scatterlist *sgl;
132 uint8_t sense_buffer[VSCSIIF_SENSE_BUFFERSIZE];
134 grant_handle_t grant_handles[VSCSI_MAX_GRANTS];
135 struct page *pages[VSCSI_MAX_GRANTS];
137 struct se_cmd se_cmd;
139 struct completion tmr_done;
142 #define VSCSI_DEFAULT_SESSION_TAGS 128
144 struct scsiback_nexus {
145 /* Pointer to TCM session for I_T Nexus */
146 struct se_session *tvn_se_sess;
149 struct scsiback_tport {
150 /* SCSI protocol the tport is providing */
152 /* Binary World Wide unique Port Name for pvscsi Target port */
154 /* ASCII formatted WWPN for pvscsi Target port */
155 char tport_name[VSCSI_NAMELEN];
156 /* Returned by scsiback_make_tport() */
157 struct se_wwn tport_wwn;
160 struct scsiback_tpg {
161 /* scsiback port target portal group tag for TCM */
163 /* track number of TPG Port/Lun Links wrt explicit I_T Nexus shutdown */
164 int tv_tpg_port_count;
165 /* xen-pvscsi references to tpg_nexus, protected by tv_tpg_mutex */
167 /* list for scsiback_list */
168 struct list_head tv_tpg_list;
169 /* Used to protect access for tpg_nexus */
170 struct mutex tv_tpg_mutex;
171 /* Pointer to the TCM pvscsi I_T Nexus for this TPG endpoint */
172 struct scsiback_nexus *tpg_nexus;
173 /* Pointer back to scsiback_tport */
174 struct scsiback_tport *tport;
175 /* Returned by scsiback_make_tpg() */
176 struct se_portal_group se_tpg;
177 /* alias used in xenstore */
178 char param_alias[VSCSI_NAMELEN];
179 /* list of info structures related to this target portal group */
180 struct list_head info_list;
183 #define SCSIBACK_INVALID_HANDLE (~0)
185 static bool log_print_stat;
186 module_param(log_print_stat, bool, 0644);
188 static int scsiback_max_buffer_pages = 1024;
189 module_param_named(max_buffer_pages, scsiback_max_buffer_pages, int, 0644);
190 MODULE_PARM_DESC(max_buffer_pages,
191 "Maximum number of free pages to keep in backend buffer");
193 /* Global spinlock to protect scsiback TPG list */
194 static DEFINE_MUTEX(scsiback_mutex);
195 static LIST_HEAD(scsiback_list);
197 static void scsiback_get(struct vscsibk_info *info)
199 atomic_inc(&info->nr_unreplied_reqs);
202 static void scsiback_put(struct vscsibk_info *info)
204 if (atomic_dec_and_test(&info->nr_unreplied_reqs))
205 wake_up(&info->waiting_to_free);
208 static unsigned long vaddr_page(struct page *page)
210 unsigned long pfn = page_to_pfn(page);
212 return (unsigned long)pfn_to_kaddr(pfn);
215 static unsigned long vaddr(struct vscsibk_pend *req, int seg)
217 return vaddr_page(req->pages[seg]);
220 static void scsiback_print_status(char *sense_buffer, int errors,
221 struct vscsibk_pend *pending_req)
223 struct scsiback_tpg *tpg = pending_req->v2p->tpg;
225 pr_err("[%s:%d] cmnd[0]=%02x -> st=%02x msg=%02x host=%02x drv=%02x\n",
226 tpg->tport->tport_name, pending_req->v2p->lun,
227 pending_req->cmnd[0], status_byte(errors), msg_byte(errors),
228 host_byte(errors), driver_byte(errors));
231 static void scsiback_fast_flush_area(struct vscsibk_pend *req)
233 struct gnttab_unmap_grant_ref unmap[VSCSI_GRANT_BATCH];
234 struct page *pages[VSCSI_GRANT_BATCH];
235 unsigned int i, invcount = 0;
236 grant_handle_t handle;
246 for (i = 0; i < req->n_grants; i++) {
247 handle = req->grant_handles[i];
248 if (handle == SCSIBACK_INVALID_HANDLE)
250 gnttab_set_unmap_op(&unmap[invcount], vaddr(req, i),
251 GNTMAP_host_map, handle);
252 req->grant_handles[i] = SCSIBACK_INVALID_HANDLE;
253 pages[invcount] = req->pages[i];
254 put_page(pages[invcount]);
256 if (invcount < VSCSI_GRANT_BATCH)
258 err = gnttab_unmap_refs(unmap, NULL, pages, invcount);
264 err = gnttab_unmap_refs(unmap, NULL, pages, invcount);
268 gnttab_page_cache_put(&req->info->free_pages, req->pages,
273 static void scsiback_free_translation_entry(struct kref *kref)
275 struct v2p_entry *entry = container_of(kref, struct v2p_entry, kref);
276 struct scsiback_tpg *tpg = entry->tpg;
278 mutex_lock(&tpg->tv_tpg_mutex);
279 tpg->tv_tpg_fe_count--;
280 mutex_unlock(&tpg->tv_tpg_mutex);
285 static void scsiback_send_response(struct vscsibk_info *info,
286 char *sense_buffer, int32_t result, uint32_t resid,
289 struct vscsiif_response *ring_res;
291 struct scsi_sense_hdr sshdr;
295 spin_lock_irqsave(&info->ring_lock, flags);
297 ring_res = RING_GET_RESPONSE(&info->ring, info->ring.rsp_prod_pvt);
298 info->ring.rsp_prod_pvt++;
300 ring_res->rslt = result;
301 ring_res->rqid = rqid;
303 if (sense_buffer != NULL &&
304 scsi_normalize_sense(sense_buffer, VSCSIIF_SENSE_BUFFERSIZE,
306 len = min_t(unsigned, 8 + sense_buffer[7],
307 VSCSIIF_SENSE_BUFFERSIZE);
308 memcpy(ring_res->sense_buffer, sense_buffer, len);
309 ring_res->sense_len = len;
311 ring_res->sense_len = 0;
314 ring_res->residual_len = resid;
316 RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&info->ring, notify);
317 spin_unlock_irqrestore(&info->ring_lock, flags);
320 notify_remote_via_irq(info->irq);
323 static void scsiback_do_resp_with_sense(char *sense_buffer, int32_t result,
324 uint32_t resid, struct vscsibk_pend *pending_req)
326 scsiback_send_response(pending_req->info, sense_buffer, result,
327 resid, pending_req->rqid);
329 if (pending_req->v2p)
330 kref_put(&pending_req->v2p->kref,
331 scsiback_free_translation_entry);
334 static void scsiback_cmd_done(struct vscsibk_pend *pending_req)
336 struct vscsibk_info *info = pending_req->info;
337 unsigned char *sense_buffer;
341 sense_buffer = pending_req->sense_buffer;
342 resid = pending_req->se_cmd.residual_count;
343 errors = pending_req->result;
345 if (errors && log_print_stat)
346 scsiback_print_status(sense_buffer, errors, pending_req);
348 scsiback_fast_flush_area(pending_req);
349 scsiback_do_resp_with_sense(sense_buffer, errors, resid, pending_req);
352 * Drop the extra KREF_ACK reference taken by target_submit_cmd_map_sgls()
353 * ahead of scsiback_check_stop_free() -> transport_generic_free_cmd()
354 * final se_cmd->cmd_kref put.
356 target_put_sess_cmd(&pending_req->se_cmd);
359 static void scsiback_cmd_exec(struct vscsibk_pend *pending_req)
361 struct se_cmd *se_cmd = &pending_req->se_cmd;
362 struct se_session *sess = pending_req->v2p->tpg->tpg_nexus->tvn_se_sess;
365 scsiback_get(pending_req->info);
366 se_cmd->tag = pending_req->rqid;
367 rc = target_submit_cmd_map_sgls(se_cmd, sess, pending_req->cmnd,
368 pending_req->sense_buffer, pending_req->v2p->lun,
369 pending_req->data_len, 0,
370 pending_req->sc_data_direction, TARGET_SCF_ACK_KREF,
371 pending_req->sgl, pending_req->n_sg,
374 transport_send_check_condition_and_sense(se_cmd,
375 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
376 transport_generic_free_cmd(se_cmd, 0);
380 static int scsiback_gnttab_data_map_batch(struct gnttab_map_grant_ref *map,
381 struct page **pg, grant_handle_t *grant, int cnt)
388 err = gnttab_map_refs(map, NULL, pg, cnt);
390 for (i = 0; i < cnt; i++) {
391 if (unlikely(map[i].status != GNTST_okay)) {
392 pr_err("invalid buffer -- could not remap it\n");
393 map[i].handle = SCSIBACK_INVALID_HANDLE;
398 grant[i] = map[i].handle;
403 static int scsiback_gnttab_data_map_list(struct vscsibk_pend *pending_req,
404 struct scsiif_request_segment *seg, struct page **pg,
405 grant_handle_t *grant, int cnt, u32 flags)
407 int mapcount = 0, i, err = 0;
408 struct gnttab_map_grant_ref map[VSCSI_GRANT_BATCH];
409 struct vscsibk_info *info = pending_req->info;
411 for (i = 0; i < cnt; i++) {
412 if (gnttab_page_cache_get(&info->free_pages, pg + mapcount)) {
413 gnttab_page_cache_put(&info->free_pages, pg, mapcount);
414 pr_err("no grant page\n");
417 gnttab_set_map_op(&map[mapcount], vaddr_page(pg[mapcount]),
418 flags, seg[i].gref, info->domid);
420 if (mapcount < VSCSI_GRANT_BATCH)
422 err = scsiback_gnttab_data_map_batch(map, pg, grant, mapcount);
425 pending_req->n_grants += mapcount;
430 err = scsiback_gnttab_data_map_batch(map, pg, grant, mapcount);
431 pending_req->n_grants += mapcount;
435 static int scsiback_gnttab_data_map(struct vscsiif_request *ring_req,
436 struct vscsibk_pend *pending_req)
439 int i, err, n_segs, i_seg = 0;
441 struct scsiif_request_segment *seg;
442 unsigned long end_seg = 0;
443 unsigned int nr_segments = (unsigned int)ring_req->nr_segments;
444 unsigned int nr_sgl = 0;
445 struct scatterlist *sg;
446 grant_handle_t *grant;
448 pending_req->n_sg = 0;
449 pending_req->n_grants = 0;
450 pending_req->data_len = 0;
452 nr_segments &= ~VSCSIIF_SG_GRANT;
456 if (nr_segments > VSCSIIF_SG_TABLESIZE) {
457 pr_debug("invalid parameter nr_seg = %d\n",
458 ring_req->nr_segments);
462 if (ring_req->nr_segments & VSCSIIF_SG_GRANT) {
463 err = scsiback_gnttab_data_map_list(pending_req, ring_req->seg,
464 pending_req->pages, pending_req->grant_handles,
465 nr_segments, GNTMAP_host_map | GNTMAP_readonly);
468 nr_sgl = nr_segments;
470 for (i = 0; i < nr_sgl; i++) {
471 n_segs = ring_req->seg[i].length /
472 sizeof(struct scsiif_request_segment);
473 if ((unsigned)ring_req->seg[i].offset +
474 (unsigned)ring_req->seg[i].length > PAGE_SIZE ||
475 n_segs * sizeof(struct scsiif_request_segment) !=
476 ring_req->seg[i].length)
478 nr_segments += n_segs;
480 if (nr_segments > SG_ALL) {
481 pr_debug("invalid nr_seg = %d\n", nr_segments);
486 /* free of (sgl) in fast_flush_area() */
487 pending_req->sgl = kmalloc_array(nr_segments,
488 sizeof(struct scatterlist), GFP_KERNEL);
489 if (!pending_req->sgl)
492 sg_init_table(pending_req->sgl, nr_segments);
493 pending_req->n_sg = nr_segments;
495 flags = GNTMAP_host_map;
496 if (pending_req->sc_data_direction == DMA_TO_DEVICE)
497 flags |= GNTMAP_readonly;
499 pg = pending_req->pages + nr_sgl;
500 grant = pending_req->grant_handles + nr_sgl;
503 err = scsiback_gnttab_data_map_list(pending_req, seg,
504 pg, grant, nr_segments, flags);
508 for (i = 0; i < nr_sgl; i++) {
509 seg = (struct scsiif_request_segment *)(
510 vaddr(pending_req, i) + ring_req->seg[i].offset);
511 n_segs = ring_req->seg[i].length /
512 sizeof(struct scsiif_request_segment);
513 err = scsiback_gnttab_data_map_list(pending_req, seg,
514 pg, grant, n_segs, flags);
520 end_seg = vaddr(pending_req, 0) + ring_req->seg[0].offset;
521 seg = (struct scsiif_request_segment *)end_seg;
522 end_seg += ring_req->seg[0].length;
523 pg = pending_req->pages + nr_sgl;
526 for_each_sg(pending_req->sgl, sg, nr_segments, i) {
527 sg_set_page(sg, pg[i], seg->length, seg->offset);
528 pending_req->data_len += seg->length;
530 if (nr_sgl && (unsigned long)seg >= end_seg) {
532 end_seg = vaddr(pending_req, i_seg) +
533 ring_req->seg[i_seg].offset;
534 seg = (struct scsiif_request_segment *)end_seg;
535 end_seg += ring_req->seg[i_seg].length;
537 if (sg->offset >= PAGE_SIZE ||
538 sg->length > PAGE_SIZE ||
539 sg->offset + sg->length > PAGE_SIZE)
546 static void scsiback_disconnect(struct vscsibk_info *info)
548 wait_event(info->waiting_to_free,
549 atomic_read(&info->nr_unreplied_reqs) == 0);
551 unbind_from_irqhandler(info->irq, info);
553 xenbus_unmap_ring_vfree(info->dev, info->ring.sring);
556 static void scsiback_device_action(struct vscsibk_pend *pending_req,
557 enum tcm_tmreq_table act, int tag)
559 struct scsiback_tpg *tpg = pending_req->v2p->tpg;
560 struct scsiback_nexus *nexus = tpg->tpg_nexus;
561 struct se_cmd *se_cmd = &pending_req->se_cmd;
562 u64 unpacked_lun = pending_req->v2p->lun;
563 int rc, err = FAILED;
565 init_completion(&pending_req->tmr_done);
567 rc = target_submit_tmr(&pending_req->se_cmd, nexus->tvn_se_sess,
568 &pending_req->sense_buffer[0],
569 unpacked_lun, NULL, act, GFP_KERNEL,
570 tag, TARGET_SCF_ACK_KREF);
574 wait_for_completion(&pending_req->tmr_done);
576 err = (se_cmd->se_tmr_req->response == TMR_FUNCTION_COMPLETE) ?
579 scsiback_do_resp_with_sense(NULL, err, 0, pending_req);
580 transport_generic_free_cmd(&pending_req->se_cmd, 0);
584 scsiback_do_resp_with_sense(NULL, err, 0, pending_req);
588 Perform virtual to physical translation
590 static struct v2p_entry *scsiback_do_translation(struct vscsibk_info *info,
593 struct v2p_entry *entry;
594 struct list_head *head = &(info->v2p_entry_lists);
597 spin_lock_irqsave(&info->v2p_lock, flags);
598 list_for_each_entry(entry, head, l) {
599 if ((entry->v.chn == v->chn) &&
600 (entry->v.tgt == v->tgt) &&
601 (entry->v.lun == v->lun)) {
602 kref_get(&entry->kref);
609 spin_unlock_irqrestore(&info->v2p_lock, flags);
613 static struct vscsibk_pend *scsiback_get_pend_req(struct vscsiif_back_ring *ring,
614 struct v2p_entry *v2p)
616 struct scsiback_tpg *tpg = v2p->tpg;
617 struct scsiback_nexus *nexus = tpg->tpg_nexus;
618 struct se_session *se_sess = nexus->tvn_se_sess;
619 struct vscsibk_pend *req;
622 tag = sbitmap_queue_get(&se_sess->sess_tag_pool, &cpu);
624 pr_err("Unable to obtain tag for vscsiif_request\n");
625 return ERR_PTR(-ENOMEM);
628 req = &((struct vscsibk_pend *)se_sess->sess_cmd_map)[tag];
629 memset(req, 0, sizeof(*req));
630 req->se_cmd.map_tag = tag;
631 req->se_cmd.map_cpu = cpu;
633 for (i = 0; i < VSCSI_MAX_GRANTS; i++)
634 req->grant_handles[i] = SCSIBACK_INVALID_HANDLE;
639 static struct vscsibk_pend *prepare_pending_reqs(struct vscsibk_info *info,
640 struct vscsiif_back_ring *ring,
641 struct vscsiif_request *ring_req)
643 struct vscsibk_pend *pending_req;
644 struct v2p_entry *v2p;
645 struct ids_tuple vir;
647 /* request range check from frontend */
648 if ((ring_req->sc_data_direction != DMA_BIDIRECTIONAL) &&
649 (ring_req->sc_data_direction != DMA_TO_DEVICE) &&
650 (ring_req->sc_data_direction != DMA_FROM_DEVICE) &&
651 (ring_req->sc_data_direction != DMA_NONE)) {
652 pr_debug("invalid parameter data_dir = %d\n",
653 ring_req->sc_data_direction);
654 return ERR_PTR(-EINVAL);
656 if (ring_req->cmd_len > VSCSIIF_MAX_COMMAND_SIZE) {
657 pr_debug("invalid parameter cmd_len = %d\n",
659 return ERR_PTR(-EINVAL);
662 vir.chn = ring_req->channel;
663 vir.tgt = ring_req->id;
664 vir.lun = ring_req->lun;
666 v2p = scsiback_do_translation(info, &vir);
668 pr_debug("the v2p of (chn:%d, tgt:%d, lun:%d) doesn't exist.\n",
669 vir.chn, vir.tgt, vir.lun);
670 return ERR_PTR(-ENODEV);
673 pending_req = scsiback_get_pend_req(ring, v2p);
674 if (IS_ERR(pending_req)) {
675 kref_put(&v2p->kref, scsiback_free_translation_entry);
676 return ERR_PTR(-ENOMEM);
678 pending_req->rqid = ring_req->rqid;
679 pending_req->info = info;
680 pending_req->v2p = v2p;
681 pending_req->sc_data_direction = ring_req->sc_data_direction;
682 pending_req->cmd_len = ring_req->cmd_len;
683 memcpy(pending_req->cmnd, ring_req->cmnd, pending_req->cmd_len);
688 static int scsiback_do_cmd_fn(struct vscsibk_info *info,
689 unsigned int *eoi_flags)
691 struct vscsiif_back_ring *ring = &info->ring;
692 struct vscsiif_request ring_req;
693 struct vscsibk_pend *pending_req;
699 rp = ring->sring->req_prod;
700 rmb(); /* guest system is accessing ring, too */
702 if (RING_REQUEST_PROD_OVERFLOW(ring, rp)) {
703 rc = ring->rsp_prod_pvt;
704 pr_warn("Dom%d provided bogus ring requests (%#x - %#x = %u). Halting ring processing\n",
705 info->domid, rp, rc, rp - rc);
710 *eoi_flags &= ~XEN_EOI_FLAG_SPURIOUS;
712 if (RING_REQUEST_CONS_OVERFLOW(ring, rc))
715 RING_COPY_REQUEST(ring, rc, &ring_req);
716 ring->req_cons = ++rc;
718 pending_req = prepare_pending_reqs(info, ring, &ring_req);
719 if (IS_ERR(pending_req)) {
720 switch (PTR_ERR(pending_req)) {
722 result = DID_NO_CONNECT;
725 result = DRIVER_ERROR;
728 scsiback_send_response(info, NULL, result << 24, 0,
733 switch (ring_req.act) {
734 case VSCSIIF_ACT_SCSI_CDB:
735 if (scsiback_gnttab_data_map(&ring_req, pending_req)) {
736 scsiback_fast_flush_area(pending_req);
737 scsiback_do_resp_with_sense(NULL,
738 DRIVER_ERROR << 24, 0, pending_req);
739 transport_generic_free_cmd(&pending_req->se_cmd, 0);
741 scsiback_cmd_exec(pending_req);
744 case VSCSIIF_ACT_SCSI_ABORT:
745 scsiback_device_action(pending_req, TMR_ABORT_TASK,
748 case VSCSIIF_ACT_SCSI_RESET:
749 scsiback_device_action(pending_req, TMR_LUN_RESET, 0);
752 pr_err_ratelimited("invalid request\n");
753 scsiback_do_resp_with_sense(NULL, DRIVER_ERROR << 24, 0,
755 transport_generic_free_cmd(&pending_req->se_cmd, 0);
759 /* Yield point for this unbounded loop. */
763 gnttab_page_cache_shrink(&info->free_pages, scsiback_max_buffer_pages);
765 RING_FINAL_CHECK_FOR_REQUESTS(&info->ring, more_to_do);
769 static irqreturn_t scsiback_irq_fn(int irq, void *dev_id)
771 struct vscsibk_info *info = dev_id;
773 unsigned int eoi_flags = XEN_EOI_FLAG_SPURIOUS;
775 while ((rc = scsiback_do_cmd_fn(info, &eoi_flags)) > 0)
778 /* In case of a ring error we keep the event channel masked. */
780 xen_irq_lateeoi(irq, eoi_flags);
785 static int scsiback_init_sring(struct vscsibk_info *info, grant_ref_t ring_ref,
786 evtchn_port_t evtchn)
789 struct vscsiif_sring *sring;
795 err = xenbus_map_ring_valloc(info->dev, &ring_ref, 1, &area);
799 sring = (struct vscsiif_sring *)area;
800 BACK_RING_INIT(&info->ring, sring, PAGE_SIZE);
802 err = bind_interdomain_evtchn_to_irq_lateeoi(info->domid, evtchn);
808 err = request_threaded_irq(info->irq, NULL, scsiback_irq_fn,
809 IRQF_ONESHOT, "vscsiif-backend", info);
816 unbind_from_irqhandler(info->irq, info);
819 xenbus_unmap_ring_vfree(info->dev, area);
824 static int scsiback_map(struct vscsibk_info *info)
826 struct xenbus_device *dev = info->dev;
827 unsigned int ring_ref;
828 evtchn_port_t evtchn;
831 err = xenbus_gather(XBT_NIL, dev->otherend,
832 "ring-ref", "%u", &ring_ref,
833 "event-channel", "%u", &evtchn, NULL);
835 xenbus_dev_fatal(dev, err, "reading %s ring", dev->otherend);
839 return scsiback_init_sring(info, ring_ref, evtchn);
843 Check for a translation entry being present
845 static struct v2p_entry *scsiback_chk_translation_entry(
846 struct vscsibk_info *info, struct ids_tuple *v)
848 struct list_head *head = &(info->v2p_entry_lists);
849 struct v2p_entry *entry;
851 list_for_each_entry(entry, head, l)
852 if ((entry->v.chn == v->chn) &&
853 (entry->v.tgt == v->tgt) &&
854 (entry->v.lun == v->lun))
861 Add a new translation entry
863 static int scsiback_add_translation_entry(struct vscsibk_info *info,
864 char *phy, struct ids_tuple *v)
867 struct v2p_entry *new;
870 unsigned long long unpacked_lun;
871 struct se_lun *se_lun;
872 struct scsiback_tpg *tpg_entry, *tpg = NULL;
873 char *error = "doesn't exist";
875 lunp = strrchr(phy, ':');
877 pr_err("illegal format of physical device %s\n", phy);
882 err = kstrtoull(lunp, 10, &unpacked_lun);
884 pr_err("lun number not valid: %s\n", lunp);
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 mutex_lock(&tpg_entry->se_tpg.tpg_lun_mutex);
893 hlist_for_each_entry(se_lun, &tpg_entry->se_tpg.tpg_lun_hlist, link) {
894 if (se_lun->unpacked_lun == unpacked_lun) {
895 if (!tpg_entry->tpg_nexus)
896 error = "nexus undefined";
902 mutex_unlock(&tpg_entry->se_tpg.tpg_lun_mutex);
907 mutex_lock(&tpg->tv_tpg_mutex);
908 tpg->tv_tpg_fe_count++;
909 mutex_unlock(&tpg->tv_tpg_mutex);
911 mutex_unlock(&scsiback_mutex);
914 pr_err("%s:%llu %s\n", phy, unpacked_lun, error);
918 new = kmalloc(sizeof(struct v2p_entry), GFP_KERNEL);
924 spin_lock_irqsave(&info->v2p_lock, flags);
926 /* Check double assignment to identical virtual ID */
927 if (scsiback_chk_translation_entry(info, v)) {
928 pr_warn("Virtual ID is already used. Assignment was not performed.\n");
933 /* Create a new translation entry and add to the list */
934 kref_init(&new->kref);
937 new->lun = unpacked_lun;
938 list_add_tail(&new->l, &info->v2p_entry_lists);
941 spin_unlock_irqrestore(&info->v2p_lock, flags);
945 mutex_lock(&tpg->tv_tpg_mutex);
946 tpg->tv_tpg_fe_count--;
947 mutex_unlock(&tpg->tv_tpg_mutex);
954 static void __scsiback_del_translation_entry(struct v2p_entry *entry)
957 kref_put(&entry->kref, scsiback_free_translation_entry);
961 Delete the translation entry specified
963 static int scsiback_del_translation_entry(struct vscsibk_info *info,
966 struct v2p_entry *entry;
970 spin_lock_irqsave(&info->v2p_lock, flags);
971 /* Find out the translation entry specified */
972 entry = scsiback_chk_translation_entry(info, v);
974 __scsiback_del_translation_entry(entry);
978 spin_unlock_irqrestore(&info->v2p_lock, flags);
982 static void scsiback_do_add_lun(struct vscsibk_info *info, const char *state,
983 char *phy, struct ids_tuple *vir, int try)
985 struct v2p_entry *entry;
990 spin_lock_irqsave(&info->v2p_lock, flags);
991 entry = scsiback_chk_translation_entry(info, vir);
992 spin_unlock_irqrestore(&info->v2p_lock, flags);
996 if (!scsiback_add_translation_entry(info, phy, vir)) {
997 if (xenbus_printf(XBT_NIL, info->dev->nodename, state,
998 "%d", XenbusStateInitialised)) {
999 pr_err("xenbus_printf error %s\n", state);
1000 scsiback_del_translation_entry(info, vir);
1003 err = xenbus_printf(XBT_NIL, info->dev->nodename, state,
1004 "%d", XenbusStateClosed);
1006 xenbus_dev_error(info->dev, err,
1007 "%s: writing %s", __func__, state);
1011 static void scsiback_do_del_lun(struct vscsibk_info *info, const char *state,
1012 struct ids_tuple *vir)
1014 if (!scsiback_del_translation_entry(info, vir)) {
1015 if (xenbus_printf(XBT_NIL, info->dev->nodename, state,
1016 "%d", XenbusStateClosed))
1017 pr_err("xenbus_printf error %s\n", state);
1021 #define VSCSIBACK_OP_ADD_OR_DEL_LUN 1
1022 #define VSCSIBACK_OP_UPDATEDEV_STATE 2
1024 static void scsiback_do_1lun_hotplug(struct vscsibk_info *info, int op,
1028 struct ids_tuple vir;
1031 char phy[VSCSI_NAMELEN];
1034 struct xenbus_device *dev = info->dev;
1037 snprintf(state, sizeof(state), "vscsi-devs/%s/state", ent);
1038 err = xenbus_scanf(XBT_NIL, dev->nodename, state, "%u", &device_state);
1039 if (XENBUS_EXIST_ERR(err))
1042 /* physical SCSI device */
1043 snprintf(str, sizeof(str), "vscsi-devs/%s/p-dev", ent);
1044 val = xenbus_read(XBT_NIL, dev->nodename, str, NULL);
1046 err = xenbus_printf(XBT_NIL, dev->nodename, state,
1047 "%d", XenbusStateClosed);
1049 xenbus_dev_error(info->dev, err,
1050 "%s: writing %s", __func__, state);
1053 strlcpy(phy, val, VSCSI_NAMELEN);
1056 /* virtual SCSI device */
1057 snprintf(str, sizeof(str), "vscsi-devs/%s/v-dev", ent);
1058 err = xenbus_scanf(XBT_NIL, dev->nodename, str, "%u:%u:%u:%u",
1059 &vir.hst, &vir.chn, &vir.tgt, &vir.lun);
1060 if (XENBUS_EXIST_ERR(err)) {
1061 err = xenbus_printf(XBT_NIL, dev->nodename, state,
1062 "%d", XenbusStateClosed);
1064 xenbus_dev_error(info->dev, err,
1065 "%s: writing %s", __func__, state);
1070 case VSCSIBACK_OP_ADD_OR_DEL_LUN:
1071 switch (device_state) {
1072 case XenbusStateInitialising:
1073 scsiback_do_add_lun(info, state, phy, &vir, 0);
1075 case XenbusStateConnected:
1076 scsiback_do_add_lun(info, state, phy, &vir, 1);
1078 case XenbusStateClosing:
1079 scsiback_do_del_lun(info, state, &vir);
1086 case VSCSIBACK_OP_UPDATEDEV_STATE:
1087 if (device_state == XenbusStateInitialised) {
1088 /* modify vscsi-devs/dev-x/state */
1089 if (xenbus_printf(XBT_NIL, dev->nodename, state,
1090 "%d", XenbusStateConnected)) {
1091 pr_err("xenbus_printf error %s\n", str);
1092 scsiback_del_translation_entry(info, &vir);
1093 xenbus_printf(XBT_NIL, dev->nodename, state,
1094 "%d", XenbusStateClosed);
1098 /* When it is necessary, processing is added here. */
1104 static void scsiback_do_lun_hotplug(struct vscsibk_info *info, int op)
1108 unsigned int ndir = 0;
1110 dir = xenbus_directory(XBT_NIL, info->dev->nodename, "vscsi-devs",
1115 for (i = 0; i < ndir; i++)
1116 scsiback_do_1lun_hotplug(info, op, dir[i]);
1121 static void scsiback_frontend_changed(struct xenbus_device *dev,
1122 enum xenbus_state frontend_state)
1124 struct vscsibk_info *info = dev_get_drvdata(&dev->dev);
1126 switch (frontend_state) {
1127 case XenbusStateInitialising:
1130 case XenbusStateInitialised:
1131 if (scsiback_map(info))
1134 scsiback_do_lun_hotplug(info, VSCSIBACK_OP_ADD_OR_DEL_LUN);
1135 xenbus_switch_state(dev, XenbusStateConnected);
1138 case XenbusStateConnected:
1139 scsiback_do_lun_hotplug(info, VSCSIBACK_OP_UPDATEDEV_STATE);
1141 if (dev->state == XenbusStateConnected)
1144 xenbus_switch_state(dev, XenbusStateConnected);
1147 case XenbusStateClosing:
1149 scsiback_disconnect(info);
1151 xenbus_switch_state(dev, XenbusStateClosing);
1154 case XenbusStateClosed:
1155 xenbus_switch_state(dev, XenbusStateClosed);
1156 if (xenbus_dev_is_online(dev))
1158 fallthrough; /* if not online */
1159 case XenbusStateUnknown:
1160 device_unregister(&dev->dev);
1163 case XenbusStateReconfiguring:
1164 scsiback_do_lun_hotplug(info, VSCSIBACK_OP_ADD_OR_DEL_LUN);
1165 xenbus_switch_state(dev, XenbusStateReconfigured);
1170 xenbus_dev_fatal(dev, -EINVAL, "saw state %d at frontend",
1177 Release the translation entry specfied
1179 static void scsiback_release_translation_entry(struct vscsibk_info *info)
1181 struct v2p_entry *entry, *tmp;
1182 struct list_head *head = &(info->v2p_entry_lists);
1183 unsigned long flags;
1185 spin_lock_irqsave(&info->v2p_lock, flags);
1187 list_for_each_entry_safe(entry, tmp, head, l)
1188 __scsiback_del_translation_entry(entry);
1190 spin_unlock_irqrestore(&info->v2p_lock, flags);
1193 static int scsiback_remove(struct xenbus_device *dev)
1195 struct vscsibk_info *info = dev_get_drvdata(&dev->dev);
1198 scsiback_disconnect(info);
1200 scsiback_release_translation_entry(info);
1202 gnttab_page_cache_shrink(&info->free_pages, 0);
1204 dev_set_drvdata(&dev->dev, NULL);
1209 static int scsiback_probe(struct xenbus_device *dev,
1210 const struct xenbus_device_id *id)
1214 struct vscsibk_info *info = kzalloc(sizeof(struct vscsibk_info),
1217 pr_debug("%s %p %d\n", __func__, dev, dev->otherend_id);
1220 xenbus_dev_fatal(dev, -ENOMEM, "allocating backend structure");
1224 dev_set_drvdata(&dev->dev, info);
1226 info->domid = dev->otherend_id;
1227 spin_lock_init(&info->ring_lock);
1228 atomic_set(&info->nr_unreplied_reqs, 0);
1229 init_waitqueue_head(&info->waiting_to_free);
1232 INIT_LIST_HEAD(&info->v2p_entry_lists);
1233 spin_lock_init(&info->v2p_lock);
1234 gnttab_page_cache_init(&info->free_pages);
1236 err = xenbus_printf(XBT_NIL, dev->nodename, "feature-sg-grant", "%u",
1239 xenbus_dev_error(dev, err, "writing feature-sg-grant");
1241 err = xenbus_switch_state(dev, XenbusStateInitWait);
1248 pr_warn("%s failed\n", __func__);
1249 scsiback_remove(dev);
1254 static char *scsiback_dump_proto_id(struct scsiback_tport *tport)
1256 switch (tport->tport_proto_id) {
1257 case SCSI_PROTOCOL_SAS:
1259 case SCSI_PROTOCOL_FCP:
1261 case SCSI_PROTOCOL_ISCSI:
1270 static char *scsiback_get_fabric_wwn(struct se_portal_group *se_tpg)
1272 struct scsiback_tpg *tpg = container_of(se_tpg,
1273 struct scsiback_tpg, se_tpg);
1274 struct scsiback_tport *tport = tpg->tport;
1276 return &tport->tport_name[0];
1279 static u16 scsiback_get_tag(struct se_portal_group *se_tpg)
1281 struct scsiback_tpg *tpg = container_of(se_tpg,
1282 struct scsiback_tpg, se_tpg);
1283 return tpg->tport_tpgt;
1286 static struct se_wwn *
1287 scsiback_make_tport(struct target_fabric_configfs *tf,
1288 struct config_group *group,
1291 struct scsiback_tport *tport;
1296 tport = kzalloc(sizeof(struct scsiback_tport), GFP_KERNEL);
1298 return ERR_PTR(-ENOMEM);
1300 tport->tport_wwpn = wwpn;
1302 * Determine the emulated Protocol Identifier and Target Port Name
1303 * based on the incoming configfs directory name.
1305 ptr = strstr(name, "naa.");
1307 tport->tport_proto_id = SCSI_PROTOCOL_SAS;
1310 ptr = strstr(name, "fc.");
1312 tport->tport_proto_id = SCSI_PROTOCOL_FCP;
1313 off = 3; /* Skip over "fc." */
1316 ptr = strstr(name, "iqn.");
1318 tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
1322 pr_err("Unable to locate prefix for emulated Target Port: %s\n", name);
1324 return ERR_PTR(-EINVAL);
1327 if (strlen(name) >= VSCSI_NAMELEN) {
1328 pr_err("Emulated %s Address: %s, exceeds max: %d\n", name,
1329 scsiback_dump_proto_id(tport), VSCSI_NAMELEN);
1331 return ERR_PTR(-EINVAL);
1333 snprintf(&tport->tport_name[0], VSCSI_NAMELEN, "%s", &name[off]);
1335 pr_debug("Allocated emulated Target %s Address: %s\n",
1336 scsiback_dump_proto_id(tport), name);
1338 return &tport->tport_wwn;
1341 static void scsiback_drop_tport(struct se_wwn *wwn)
1343 struct scsiback_tport *tport = container_of(wwn,
1344 struct scsiback_tport, tport_wwn);
1346 pr_debug("Deallocating emulated Target %s Address: %s\n",
1347 scsiback_dump_proto_id(tport), tport->tport_name);
1352 static u32 scsiback_tpg_get_inst_index(struct se_portal_group *se_tpg)
1357 static int scsiback_check_stop_free(struct se_cmd *se_cmd)
1359 return transport_generic_free_cmd(se_cmd, 0);
1362 static void scsiback_release_cmd(struct se_cmd *se_cmd)
1364 target_free_tag(se_cmd->se_sess, se_cmd);
1367 static u32 scsiback_sess_get_index(struct se_session *se_sess)
1372 static int scsiback_write_pending(struct se_cmd *se_cmd)
1374 /* Go ahead and process the write immediately */
1375 target_execute_cmd(se_cmd);
1380 static void scsiback_set_default_node_attrs(struct se_node_acl *nacl)
1384 static int scsiback_get_cmd_state(struct se_cmd *se_cmd)
1389 static int scsiback_queue_data_in(struct se_cmd *se_cmd)
1391 struct vscsibk_pend *pending_req = container_of(se_cmd,
1392 struct vscsibk_pend, se_cmd);
1394 pending_req->result = SAM_STAT_GOOD;
1395 scsiback_cmd_done(pending_req);
1399 static int scsiback_queue_status(struct se_cmd *se_cmd)
1401 struct vscsibk_pend *pending_req = container_of(se_cmd,
1402 struct vscsibk_pend, se_cmd);
1404 if (se_cmd->sense_buffer &&
1405 ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
1406 (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE)))
1407 pending_req->result = (DRIVER_SENSE << 24) |
1408 SAM_STAT_CHECK_CONDITION;
1410 pending_req->result = se_cmd->scsi_status;
1412 scsiback_cmd_done(pending_req);
1416 static void scsiback_queue_tm_rsp(struct se_cmd *se_cmd)
1418 struct vscsibk_pend *pending_req = container_of(se_cmd,
1419 struct vscsibk_pend, se_cmd);
1421 complete(&pending_req->tmr_done);
1424 static void scsiback_aborted_task(struct se_cmd *se_cmd)
1428 static ssize_t scsiback_tpg_param_alias_show(struct config_item *item,
1431 struct se_portal_group *se_tpg = param_to_tpg(item);
1432 struct scsiback_tpg *tpg = container_of(se_tpg, struct scsiback_tpg,
1436 mutex_lock(&tpg->tv_tpg_mutex);
1437 rb = snprintf(page, PAGE_SIZE, "%s\n", tpg->param_alias);
1438 mutex_unlock(&tpg->tv_tpg_mutex);
1443 static ssize_t scsiback_tpg_param_alias_store(struct config_item *item,
1444 const char *page, size_t count)
1446 struct se_portal_group *se_tpg = param_to_tpg(item);
1447 struct scsiback_tpg *tpg = container_of(se_tpg, struct scsiback_tpg,
1451 if (strlen(page) >= VSCSI_NAMELEN) {
1452 pr_err("param alias: %s, exceeds max: %d\n", page,
1457 mutex_lock(&tpg->tv_tpg_mutex);
1458 len = snprintf(tpg->param_alias, VSCSI_NAMELEN, "%s", page);
1459 if (tpg->param_alias[len - 1] == '\n')
1460 tpg->param_alias[len - 1] = '\0';
1461 mutex_unlock(&tpg->tv_tpg_mutex);
1466 CONFIGFS_ATTR(scsiback_tpg_param_, alias);
1468 static struct configfs_attribute *scsiback_param_attrs[] = {
1469 &scsiback_tpg_param_attr_alias,
1473 static int scsiback_alloc_sess_cb(struct se_portal_group *se_tpg,
1474 struct se_session *se_sess, void *p)
1476 struct scsiback_tpg *tpg = container_of(se_tpg,
1477 struct scsiback_tpg, se_tpg);
1483 static int scsiback_make_nexus(struct scsiback_tpg *tpg,
1486 struct scsiback_nexus *tv_nexus;
1489 mutex_lock(&tpg->tv_tpg_mutex);
1490 if (tpg->tpg_nexus) {
1491 pr_debug("tpg->tpg_nexus already exists\n");
1496 tv_nexus = kzalloc(sizeof(struct scsiback_nexus), GFP_KERNEL);
1502 tv_nexus->tvn_se_sess = target_setup_session(&tpg->se_tpg,
1503 VSCSI_DEFAULT_SESSION_TAGS,
1504 sizeof(struct vscsibk_pend),
1505 TARGET_PROT_NORMAL, name,
1506 tv_nexus, scsiback_alloc_sess_cb);
1507 if (IS_ERR(tv_nexus->tvn_se_sess)) {
1514 mutex_unlock(&tpg->tv_tpg_mutex);
1518 static int scsiback_drop_nexus(struct scsiback_tpg *tpg)
1520 struct se_session *se_sess;
1521 struct scsiback_nexus *tv_nexus;
1523 mutex_lock(&tpg->tv_tpg_mutex);
1524 tv_nexus = tpg->tpg_nexus;
1526 mutex_unlock(&tpg->tv_tpg_mutex);
1530 se_sess = tv_nexus->tvn_se_sess;
1532 mutex_unlock(&tpg->tv_tpg_mutex);
1536 if (tpg->tv_tpg_port_count != 0) {
1537 mutex_unlock(&tpg->tv_tpg_mutex);
1538 pr_err("Unable to remove xen-pvscsi I_T Nexus with active TPG port count: %d\n",
1539 tpg->tv_tpg_port_count);
1543 if (tpg->tv_tpg_fe_count != 0) {
1544 mutex_unlock(&tpg->tv_tpg_mutex);
1545 pr_err("Unable to remove xen-pvscsi I_T Nexus with active TPG frontend count: %d\n",
1546 tpg->tv_tpg_fe_count);
1550 pr_debug("Removing I_T Nexus to emulated %s Initiator Port: %s\n",
1551 scsiback_dump_proto_id(tpg->tport),
1552 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1555 * Release the SCSI I_T Nexus to the emulated xen-pvscsi Target Port
1557 target_remove_session(se_sess);
1558 tpg->tpg_nexus = NULL;
1559 mutex_unlock(&tpg->tv_tpg_mutex);
1565 static ssize_t scsiback_tpg_nexus_show(struct config_item *item, char *page)
1567 struct se_portal_group *se_tpg = to_tpg(item);
1568 struct scsiback_tpg *tpg = container_of(se_tpg,
1569 struct scsiback_tpg, se_tpg);
1570 struct scsiback_nexus *tv_nexus;
1573 mutex_lock(&tpg->tv_tpg_mutex);
1574 tv_nexus = tpg->tpg_nexus;
1576 mutex_unlock(&tpg->tv_tpg_mutex);
1579 ret = snprintf(page, PAGE_SIZE, "%s\n",
1580 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1581 mutex_unlock(&tpg->tv_tpg_mutex);
1586 static ssize_t scsiback_tpg_nexus_store(struct config_item *item,
1587 const char *page, size_t count)
1589 struct se_portal_group *se_tpg = to_tpg(item);
1590 struct scsiback_tpg *tpg = container_of(se_tpg,
1591 struct scsiback_tpg, se_tpg);
1592 struct scsiback_tport *tport_wwn = tpg->tport;
1593 unsigned char i_port[VSCSI_NAMELEN], *ptr, *port_ptr;
1596 * Shutdown the active I_T nexus if 'NULL' is passed.
1598 if (!strncmp(page, "NULL", 4)) {
1599 ret = scsiback_drop_nexus(tpg);
1600 return (!ret) ? count : ret;
1603 * Otherwise make sure the passed virtual Initiator port WWN matches
1604 * the fabric protocol_id set in scsiback_make_tport(), and call
1605 * scsiback_make_nexus().
1607 if (strlen(page) >= VSCSI_NAMELEN) {
1608 pr_err("Emulated NAA Sas Address: %s, exceeds max: %d\n",
1609 page, VSCSI_NAMELEN);
1612 snprintf(&i_port[0], VSCSI_NAMELEN, "%s", page);
1614 ptr = strstr(i_port, "naa.");
1616 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
1617 pr_err("Passed SAS Initiator Port %s does not match target port protoid: %s\n",
1618 i_port, scsiback_dump_proto_id(tport_wwn));
1621 port_ptr = &i_port[0];
1624 ptr = strstr(i_port, "fc.");
1626 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
1627 pr_err("Passed FCP Initiator Port %s does not match target port protoid: %s\n",
1628 i_port, scsiback_dump_proto_id(tport_wwn));
1631 port_ptr = &i_port[3]; /* Skip over "fc." */
1634 ptr = strstr(i_port, "iqn.");
1636 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
1637 pr_err("Passed iSCSI Initiator Port %s does not match target port protoid: %s\n",
1638 i_port, scsiback_dump_proto_id(tport_wwn));
1641 port_ptr = &i_port[0];
1644 pr_err("Unable to locate prefix for emulated Initiator Port: %s\n",
1648 * Clear any trailing newline for the NAA WWN
1651 if (i_port[strlen(i_port) - 1] == '\n')
1652 i_port[strlen(i_port) - 1] = '\0';
1654 ret = scsiback_make_nexus(tpg, port_ptr);
1661 CONFIGFS_ATTR(scsiback_tpg_, nexus);
1663 static struct configfs_attribute *scsiback_tpg_attrs[] = {
1664 &scsiback_tpg_attr_nexus,
1669 scsiback_wwn_version_show(struct config_item *item, char *page)
1671 return sprintf(page, "xen-pvscsi fabric module %s on %s/%s on "
1673 VSCSI_VERSION, utsname()->sysname, utsname()->machine);
1676 CONFIGFS_ATTR_RO(scsiback_wwn_, version);
1678 static struct configfs_attribute *scsiback_wwn_attrs[] = {
1679 &scsiback_wwn_attr_version,
1683 static int scsiback_port_link(struct se_portal_group *se_tpg,
1686 struct scsiback_tpg *tpg = container_of(se_tpg,
1687 struct scsiback_tpg, se_tpg);
1689 mutex_lock(&tpg->tv_tpg_mutex);
1690 tpg->tv_tpg_port_count++;
1691 mutex_unlock(&tpg->tv_tpg_mutex);
1696 static void scsiback_port_unlink(struct se_portal_group *se_tpg,
1699 struct scsiback_tpg *tpg = container_of(se_tpg,
1700 struct scsiback_tpg, se_tpg);
1702 mutex_lock(&tpg->tv_tpg_mutex);
1703 tpg->tv_tpg_port_count--;
1704 mutex_unlock(&tpg->tv_tpg_mutex);
1707 static struct se_portal_group *
1708 scsiback_make_tpg(struct se_wwn *wwn, const char *name)
1710 struct scsiback_tport *tport = container_of(wwn,
1711 struct scsiback_tport, tport_wwn);
1713 struct scsiback_tpg *tpg;
1717 if (strstr(name, "tpgt_") != name)
1718 return ERR_PTR(-EINVAL);
1719 ret = kstrtou16(name + 5, 10, &tpgt);
1721 return ERR_PTR(ret);
1723 tpg = kzalloc(sizeof(struct scsiback_tpg), GFP_KERNEL);
1725 return ERR_PTR(-ENOMEM);
1727 mutex_init(&tpg->tv_tpg_mutex);
1728 INIT_LIST_HEAD(&tpg->tv_tpg_list);
1729 INIT_LIST_HEAD(&tpg->info_list);
1731 tpg->tport_tpgt = tpgt;
1733 ret = core_tpg_register(wwn, &tpg->se_tpg, tport->tport_proto_id);
1738 mutex_lock(&scsiback_mutex);
1739 list_add_tail(&tpg->tv_tpg_list, &scsiback_list);
1740 mutex_unlock(&scsiback_mutex);
1742 return &tpg->se_tpg;
1745 static void scsiback_drop_tpg(struct se_portal_group *se_tpg)
1747 struct scsiback_tpg *tpg = container_of(se_tpg,
1748 struct scsiback_tpg, se_tpg);
1750 mutex_lock(&scsiback_mutex);
1751 list_del(&tpg->tv_tpg_list);
1752 mutex_unlock(&scsiback_mutex);
1754 * Release the virtual I_T Nexus for this xen-pvscsi TPG
1756 scsiback_drop_nexus(tpg);
1758 * Deregister the se_tpg from TCM.
1760 core_tpg_deregister(se_tpg);
1764 static int scsiback_check_true(struct se_portal_group *se_tpg)
1769 static int scsiback_check_false(struct se_portal_group *se_tpg)
1774 static const struct target_core_fabric_ops scsiback_ops = {
1775 .module = THIS_MODULE,
1776 .fabric_name = "xen-pvscsi",
1777 .tpg_get_wwn = scsiback_get_fabric_wwn,
1778 .tpg_get_tag = scsiback_get_tag,
1779 .tpg_check_demo_mode = scsiback_check_true,
1780 .tpg_check_demo_mode_cache = scsiback_check_true,
1781 .tpg_check_demo_mode_write_protect = scsiback_check_false,
1782 .tpg_check_prod_mode_write_protect = scsiback_check_false,
1783 .tpg_get_inst_index = scsiback_tpg_get_inst_index,
1784 .check_stop_free = scsiback_check_stop_free,
1785 .release_cmd = scsiback_release_cmd,
1786 .sess_get_index = scsiback_sess_get_index,
1787 .sess_get_initiator_sid = NULL,
1788 .write_pending = scsiback_write_pending,
1789 .set_default_node_attributes = scsiback_set_default_node_attrs,
1790 .get_cmd_state = scsiback_get_cmd_state,
1791 .queue_data_in = scsiback_queue_data_in,
1792 .queue_status = scsiback_queue_status,
1793 .queue_tm_rsp = scsiback_queue_tm_rsp,
1794 .aborted_task = scsiback_aborted_task,
1796 * Setup callers for generic logic in target_core_fabric_configfs.c
1798 .fabric_make_wwn = scsiback_make_tport,
1799 .fabric_drop_wwn = scsiback_drop_tport,
1800 .fabric_make_tpg = scsiback_make_tpg,
1801 .fabric_drop_tpg = scsiback_drop_tpg,
1802 .fabric_post_link = scsiback_port_link,
1803 .fabric_pre_unlink = scsiback_port_unlink,
1805 .tfc_wwn_attrs = scsiback_wwn_attrs,
1806 .tfc_tpg_base_attrs = scsiback_tpg_attrs,
1807 .tfc_tpg_param_attrs = scsiback_param_attrs,
1810 static const struct xenbus_device_id scsiback_ids[] = {
1815 static struct xenbus_driver scsiback_driver = {
1816 .ids = scsiback_ids,
1817 .probe = scsiback_probe,
1818 .remove = scsiback_remove,
1819 .otherend_changed = scsiback_frontend_changed
1822 static int __init scsiback_init(void)
1829 pr_debug("xen-pvscsi: fabric module %s on %s/%s on "UTS_RELEASE"\n",
1830 VSCSI_VERSION, utsname()->sysname, utsname()->machine);
1832 ret = xenbus_register_backend(&scsiback_driver);
1836 ret = target_register_template(&scsiback_ops);
1838 goto out_unregister_xenbus;
1842 out_unregister_xenbus:
1843 xenbus_unregister_driver(&scsiback_driver);
1845 pr_err("%s: error %d\n", __func__, ret);
1849 static void __exit scsiback_exit(void)
1851 target_unregister_template(&scsiback_ops);
1852 xenbus_unregister_driver(&scsiback_driver);
1855 module_init(scsiback_init);
1856 module_exit(scsiback_exit);
1858 MODULE_DESCRIPTION("Xen SCSI backend driver");
1859 MODULE_LICENSE("Dual BSD/GPL");
1860 MODULE_ALIAS("xen-backend:vscsi");
1861 MODULE_AUTHOR("Juergen Gross <jgross@suse.com>");