/* * Xen SCSI backend driver * * Copyright (c) 2008, FUJITSU Limited * * Based on the blkback driver code. * Adaption to kernel taget core infrastructure taken from vhost/scsi.c * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License version 2 * as published by the Free Software Foundation; or, when distributed * separately from the Linux kernel or incorporated into other * software packages, subject to the following license: * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this source file (the "Software"), to deal in the Software without * restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, * and to permit persons to whom the Software is furnished to do so, subject to * the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS * IN THE SOFTWARE. */ #define pr_fmt(fmt) "xen-pvscsi: " fmt #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* SG_ALL */ #include #include #include #include #include #include #include #include #include #include #include #define VSCSI_VERSION "v0.1" #define VSCSI_NAMELEN 32 struct ids_tuple { unsigned int hst; /* host */ unsigned int chn; /* channel */ unsigned int tgt; /* target */ unsigned int lun; /* LUN */ }; struct v2p_entry { struct ids_tuple v; /* translate from */ struct scsiback_tpg *tpg; /* translate to */ unsigned int lun; struct kref kref; struct list_head l; }; struct vscsibk_info { struct xenbus_device *dev; domid_t domid; unsigned int irq; struct vscsiif_back_ring ring; int ring_error; spinlock_t ring_lock; atomic_t nr_unreplied_reqs; spinlock_t v2p_lock; struct list_head v2p_entry_lists; wait_queue_head_t waiting_to_free; }; /* theoretical maximum of grants for one request */ #define VSCSI_MAX_GRANTS (SG_ALL + VSCSIIF_SG_TABLESIZE) /* * VSCSI_GRANT_BATCH is the maximum number of grants to be processed in one * call to map/unmap grants. Don't choose it too large, as there are arrays * with VSCSI_GRANT_BATCH elements allocated on the stack. */ #define VSCSI_GRANT_BATCH 16 struct vscsibk_pend { uint16_t rqid; uint8_t cmnd[VSCSIIF_MAX_COMMAND_SIZE]; uint8_t cmd_len; uint8_t sc_data_direction; uint16_t n_sg; /* real length of SG list */ uint16_t n_grants; /* SG pages and potentially SG list */ uint32_t data_len; uint32_t result; struct vscsibk_info *info; struct v2p_entry *v2p; struct scatterlist *sgl; uint8_t sense_buffer[VSCSIIF_SENSE_BUFFERSIZE]; grant_handle_t grant_handles[VSCSI_MAX_GRANTS]; struct page *pages[VSCSI_MAX_GRANTS]; struct se_cmd se_cmd; struct completion tmr_done; }; #define VSCSI_DEFAULT_SESSION_TAGS 128 struct scsiback_nexus { /* Pointer to TCM session for I_T Nexus */ struct se_session *tvn_se_sess; }; struct scsiback_tport { /* SCSI protocol the tport is providing */ u8 tport_proto_id; /* Binary World Wide unique Port Name for pvscsi Target port */ u64 tport_wwpn; /* ASCII formatted WWPN for pvscsi Target port */ char tport_name[VSCSI_NAMELEN]; /* Returned by scsiback_make_tport() */ struct se_wwn tport_wwn; }; struct scsiback_tpg { /* scsiback port target portal group tag for TCM */ u16 tport_tpgt; /* track number of TPG Port/Lun Links wrt explicit I_T Nexus shutdown */ int tv_tpg_port_count; /* xen-pvscsi references to tpg_nexus, protected by tv_tpg_mutex */ int tv_tpg_fe_count; /* list for scsiback_list */ struct list_head tv_tpg_list; /* Used to protect access for tpg_nexus */ struct mutex tv_tpg_mutex; /* Pointer to the TCM pvscsi I_T Nexus for this TPG endpoint */ struct scsiback_nexus *tpg_nexus; /* Pointer back to scsiback_tport */ struct scsiback_tport *tport; /* Returned by scsiback_make_tpg() */ struct se_portal_group se_tpg; /* alias used in xenstore */ char param_alias[VSCSI_NAMELEN]; /* list of info structures related to this target portal group */ struct list_head info_list; }; #define SCSIBACK_INVALID_HANDLE (~0) static bool log_print_stat; module_param(log_print_stat, bool, 0644); static int scsiback_max_buffer_pages = 1024; module_param_named(max_buffer_pages, scsiback_max_buffer_pages, int, 0644); MODULE_PARM_DESC(max_buffer_pages, "Maximum number of free pages to keep in backend buffer"); static DEFINE_SPINLOCK(free_pages_lock); static int free_pages_num; static LIST_HEAD(scsiback_free_pages); /* Global spinlock to protect scsiback TPG list */ static DEFINE_MUTEX(scsiback_mutex); static LIST_HEAD(scsiback_list); static void scsiback_get(struct vscsibk_info *info) { atomic_inc(&info->nr_unreplied_reqs); } static void scsiback_put(struct vscsibk_info *info) { if (atomic_dec_and_test(&info->nr_unreplied_reqs)) wake_up(&info->waiting_to_free); } static void put_free_pages(struct page **page, int num) { unsigned long flags; int i = free_pages_num + num, n = num; if (num == 0) return; if (i > scsiback_max_buffer_pages) { n = min(num, i - scsiback_max_buffer_pages); gnttab_free_pages(n, page + num - n); n = num - n; } spin_lock_irqsave(&free_pages_lock, flags); for (i = 0; i < n; i++) list_add(&page[i]->lru, &scsiback_free_pages); free_pages_num += n; spin_unlock_irqrestore(&free_pages_lock, flags); } static int get_free_page(struct page **page) { unsigned long flags; spin_lock_irqsave(&free_pages_lock, flags); if (list_empty(&scsiback_free_pages)) { spin_unlock_irqrestore(&free_pages_lock, flags); return gnttab_alloc_pages(1, page); } page[0] = list_first_entry(&scsiback_free_pages, struct page, lru); list_del(&page[0]->lru); free_pages_num--; spin_unlock_irqrestore(&free_pages_lock, flags); return 0; } static unsigned long vaddr_page(struct page *page) { unsigned long pfn = page_to_pfn(page); return (unsigned long)pfn_to_kaddr(pfn); } static unsigned long vaddr(struct vscsibk_pend *req, int seg) { return vaddr_page(req->pages[seg]); } static void scsiback_print_status(char *sense_buffer, int errors, struct vscsibk_pend *pending_req) { struct scsiback_tpg *tpg = pending_req->v2p->tpg; pr_err("[%s:%d] cmnd[0]=%02x -> st=%02x msg=%02x host=%02x drv=%02x\n", tpg->tport->tport_name, pending_req->v2p->lun, pending_req->cmnd[0], status_byte(errors), msg_byte(errors), host_byte(errors), driver_byte(errors)); } static void scsiback_fast_flush_area(struct vscsibk_pend *req) { struct gnttab_unmap_grant_ref unmap[VSCSI_GRANT_BATCH]; struct page *pages[VSCSI_GRANT_BATCH]; unsigned int i, invcount = 0; grant_handle_t handle; int err; kfree(req->sgl); req->sgl = NULL; req->n_sg = 0; if (!req->n_grants) return; for (i = 0; i < req->n_grants; i++) { handle = req->grant_handles[i]; if (handle == SCSIBACK_INVALID_HANDLE) continue; gnttab_set_unmap_op(&unmap[invcount], vaddr(req, i), GNTMAP_host_map, handle); req->grant_handles[i] = SCSIBACK_INVALID_HANDLE; pages[invcount] = req->pages[i]; put_page(pages[invcount]); invcount++; if (invcount < VSCSI_GRANT_BATCH) continue; err = gnttab_unmap_refs(unmap, NULL, pages, invcount); BUG_ON(err); invcount = 0; } if (invcount) { err = gnttab_unmap_refs(unmap, NULL, pages, invcount); BUG_ON(err); } put_free_pages(req->pages, req->n_grants); req->n_grants = 0; } static void scsiback_free_translation_entry(struct kref *kref) { struct v2p_entry *entry = container_of(kref, struct v2p_entry, kref); struct scsiback_tpg *tpg = entry->tpg; mutex_lock(&tpg->tv_tpg_mutex); tpg->tv_tpg_fe_count--; mutex_unlock(&tpg->tv_tpg_mutex); kfree(entry); } static void scsiback_send_response(struct vscsibk_info *info, char *sense_buffer, int32_t result, uint32_t resid, uint16_t rqid) { struct vscsiif_response *ring_res; int notify; struct scsi_sense_hdr sshdr; unsigned long flags; unsigned len; spin_lock_irqsave(&info->ring_lock, flags); ring_res = RING_GET_RESPONSE(&info->ring, info->ring.rsp_prod_pvt); info->ring.rsp_prod_pvt++; ring_res->rslt = result; ring_res->rqid = rqid; if (sense_buffer != NULL && scsi_normalize_sense(sense_buffer, VSCSIIF_SENSE_BUFFERSIZE, &sshdr)) { len = min_t(unsigned, 8 + sense_buffer[7], VSCSIIF_SENSE_BUFFERSIZE); memcpy(ring_res->sense_buffer, sense_buffer, len); ring_res->sense_len = len; } else { ring_res->sense_len = 0; } ring_res->residual_len = resid; RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&info->ring, notify); spin_unlock_irqrestore(&info->ring_lock, flags); if (notify) notify_remote_via_irq(info->irq); } static void scsiback_do_resp_with_sense(char *sense_buffer, int32_t result, uint32_t resid, struct vscsibk_pend *pending_req) { scsiback_send_response(pending_req->info, sense_buffer, result, resid, pending_req->rqid); if (pending_req->v2p) kref_put(&pending_req->v2p->kref, scsiback_free_translation_entry); } static void scsiback_cmd_done(struct vscsibk_pend *pending_req) { struct vscsibk_info *info = pending_req->info; unsigned char *sense_buffer; unsigned int resid; int errors; sense_buffer = pending_req->sense_buffer; resid = pending_req->se_cmd.residual_count; errors = pending_req->result; if (errors && log_print_stat) scsiback_print_status(sense_buffer, errors, pending_req); scsiback_fast_flush_area(pending_req); scsiback_do_resp_with_sense(sense_buffer, errors, resid, pending_req); scsiback_put(info); /* * Drop the extra KREF_ACK reference taken by target_submit_cmd_map_sgls() * ahead of scsiback_check_stop_free() -> transport_generic_free_cmd() * final se_cmd->cmd_kref put. */ target_put_sess_cmd(&pending_req->se_cmd); } static void scsiback_cmd_exec(struct vscsibk_pend *pending_req) { struct se_cmd *se_cmd = &pending_req->se_cmd; struct se_session *sess = pending_req->v2p->tpg->tpg_nexus->tvn_se_sess; int rc; scsiback_get(pending_req->info); se_cmd->tag = pending_req->rqid; rc = target_submit_cmd_map_sgls(se_cmd, sess, pending_req->cmnd, pending_req->sense_buffer, pending_req->v2p->lun, pending_req->data_len, 0, pending_req->sc_data_direction, TARGET_SCF_ACK_KREF, pending_req->sgl, pending_req->n_sg, NULL, 0, NULL, 0); if (rc < 0) { transport_send_check_condition_and_sense(se_cmd, TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0); transport_generic_free_cmd(se_cmd, 0); } } static int scsiback_gnttab_data_map_batch(struct gnttab_map_grant_ref *map, struct page **pg, grant_handle_t *grant, int cnt) { int err, i; if (!cnt) return 0; err = gnttab_map_refs(map, NULL, pg, cnt); BUG_ON(err); for (i = 0; i < cnt; i++) { if (unlikely(map[i].status != GNTST_okay)) { pr_err("invalid buffer -- could not remap it\n"); map[i].handle = SCSIBACK_INVALID_HANDLE; err = -ENOMEM; } else { get_page(pg[i]); } grant[i] = map[i].handle; } return err; } static int scsiback_gnttab_data_map_list(struct vscsibk_pend *pending_req, struct scsiif_request_segment *seg, struct page **pg, grant_handle_t *grant, int cnt, u32 flags) { int mapcount = 0, i, err = 0; struct gnttab_map_grant_ref map[VSCSI_GRANT_BATCH]; struct vscsibk_info *info = pending_req->info; for (i = 0; i < cnt; i++) { if (get_free_page(pg + mapcount)) { put_free_pages(pg, mapcount); pr_err("no grant page\n"); return -ENOMEM; } gnttab_set_map_op(&map[mapcount], vaddr_page(pg[mapcount]), flags, seg[i].gref, info->domid); mapcount++; if (mapcount < VSCSI_GRANT_BATCH) continue; err = scsiback_gnttab_data_map_batch(map, pg, grant, mapcount); pg += mapcount; grant += mapcount; pending_req->n_grants += mapcount; if (err) return err; mapcount = 0; } err = scsiback_gnttab_data_map_batch(map, pg, grant, mapcount); pending_req->n_grants += mapcount; return err; } static int scsiback_gnttab_data_map(struct vscsiif_request *ring_req, struct vscsibk_pend *pending_req) { u32 flags; int i, err, n_segs, i_seg = 0; struct page **pg; struct scsiif_request_segment *seg; unsigned long end_seg = 0; unsigned int nr_segments = (unsigned int)ring_req->nr_segments; unsigned int nr_sgl = 0; struct scatterlist *sg; grant_handle_t *grant; pending_req->n_sg = 0; pending_req->n_grants = 0; pending_req->data_len = 0; nr_segments &= ~VSCSIIF_SG_GRANT; if (!nr_segments) return 0; if (nr_segments > VSCSIIF_SG_TABLESIZE) { pr_debug("invalid parameter nr_seg = %d\n", ring_req->nr_segments); return -EINVAL; } if (ring_req->nr_segments & VSCSIIF_SG_GRANT) { err = scsiback_gnttab_data_map_list(pending_req, ring_req->seg, pending_req->pages, pending_req->grant_handles, nr_segments, GNTMAP_host_map | GNTMAP_readonly); if (err) return err; nr_sgl = nr_segments; nr_segments = 0; for (i = 0; i < nr_sgl; i++) { n_segs = ring_req->seg[i].length / sizeof(struct scsiif_request_segment); if ((unsigned)ring_req->seg[i].offset + (unsigned)ring_req->seg[i].length > PAGE_SIZE || n_segs * sizeof(struct scsiif_request_segment) != ring_req->seg[i].length) return -EINVAL; nr_segments += n_segs; } if (nr_segments > SG_ALL) { pr_debug("invalid nr_seg = %d\n", nr_segments); return -EINVAL; } } /* free of (sgl) in fast_flush_area() */ pending_req->sgl = kmalloc_array(nr_segments, sizeof(struct scatterlist), GFP_KERNEL); if (!pending_req->sgl) return -ENOMEM; sg_init_table(pending_req->sgl, nr_segments); pending_req->n_sg = nr_segments; flags = GNTMAP_host_map; if (pending_req->sc_data_direction == DMA_TO_DEVICE) flags |= GNTMAP_readonly; pg = pending_req->pages + nr_sgl; grant = pending_req->grant_handles + nr_sgl; if (!nr_sgl) { seg = ring_req->seg; err = scsiback_gnttab_data_map_list(pending_req, seg, pg, grant, nr_segments, flags); if (err) return err; } else { for (i = 0; i < nr_sgl; i++) { seg = (struct scsiif_request_segment *)( vaddr(pending_req, i) + ring_req->seg[i].offset); n_segs = ring_req->seg[i].length / sizeof(struct scsiif_request_segment); err = scsiback_gnttab_data_map_list(pending_req, seg, pg, grant, n_segs, flags); if (err) return err; pg += n_segs; grant += n_segs; } end_seg = vaddr(pending_req, 0) + ring_req->seg[0].offset; seg = (struct scsiif_request_segment *)end_seg; end_seg += ring_req->seg[0].length; pg = pending_req->pages + nr_sgl; } for_each_sg(pending_req->sgl, sg, nr_segments, i) { sg_set_page(sg, pg[i], seg->length, seg->offset); pending_req->data_len += seg->length; seg++; if (nr_sgl && (unsigned long)seg >= end_seg) { i_seg++; end_seg = vaddr(pending_req, i_seg) + ring_req->seg[i_seg].offset; seg = (struct scsiif_request_segment *)end_seg; end_seg += ring_req->seg[i_seg].length; } if (sg->offset >= PAGE_SIZE || sg->length > PAGE_SIZE || sg->offset + sg->length > PAGE_SIZE) return -EINVAL; } return 0; } static void scsiback_disconnect(struct vscsibk_info *info) { wait_event(info->waiting_to_free, atomic_read(&info->nr_unreplied_reqs) == 0); unbind_from_irqhandler(info->irq, info); info->irq = 0; xenbus_unmap_ring_vfree(info->dev, info->ring.sring); } static void scsiback_device_action(struct vscsibk_pend *pending_req, enum tcm_tmreq_table act, int tag) { struct scsiback_tpg *tpg = pending_req->v2p->tpg; struct scsiback_nexus *nexus = tpg->tpg_nexus; struct se_cmd *se_cmd = &pending_req->se_cmd; u64 unpacked_lun = pending_req->v2p->lun; int rc, err = FAILED; init_completion(&pending_req->tmr_done); rc = target_submit_tmr(&pending_req->se_cmd, nexus->tvn_se_sess, &pending_req->sense_buffer[0], unpacked_lun, NULL, act, GFP_KERNEL, tag, TARGET_SCF_ACK_KREF); if (rc) goto err; wait_for_completion(&pending_req->tmr_done); err = (se_cmd->se_tmr_req->response == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED; scsiback_do_resp_with_sense(NULL, err, 0, pending_req); transport_generic_free_cmd(&pending_req->se_cmd, 0); return; err: scsiback_do_resp_with_sense(NULL, err, 0, pending_req); } /* Perform virtual to physical translation */ static struct v2p_entry *scsiback_do_translation(struct vscsibk_info *info, struct ids_tuple *v) { struct v2p_entry *entry; struct list_head *head = &(info->v2p_entry_lists); unsigned long flags; spin_lock_irqsave(&info->v2p_lock, flags); list_for_each_entry(entry, head, l) { if ((entry->v.chn == v->chn) && (entry->v.tgt == v->tgt) && (entry->v.lun == v->lun)) { kref_get(&entry->kref); goto out; } } entry = NULL; out: spin_unlock_irqrestore(&info->v2p_lock, flags); return entry; } static struct vscsibk_pend *scsiback_get_pend_req(struct vscsiif_back_ring *ring, struct v2p_entry *v2p) { struct scsiback_tpg *tpg = v2p->tpg; struct scsiback_nexus *nexus = tpg->tpg_nexus; struct se_session *se_sess = nexus->tvn_se_sess; struct vscsibk_pend *req; int tag, cpu, i; tag = sbitmap_queue_get(&se_sess->sess_tag_pool, &cpu); if (tag < 0) { pr_err("Unable to obtain tag for vscsiif_request\n"); return ERR_PTR(-ENOMEM); } req = &((struct vscsibk_pend *)se_sess->sess_cmd_map)[tag]; memset(req, 0, sizeof(*req)); req->se_cmd.map_tag = tag; req->se_cmd.map_cpu = cpu; for (i = 0; i < VSCSI_MAX_GRANTS; i++) req->grant_handles[i] = SCSIBACK_INVALID_HANDLE; return req; } static struct vscsibk_pend *prepare_pending_reqs(struct vscsibk_info *info, struct vscsiif_back_ring *ring, struct vscsiif_request *ring_req) { struct vscsibk_pend *pending_req; struct v2p_entry *v2p; struct ids_tuple vir; /* request range check from frontend */ if ((ring_req->sc_data_direction != DMA_BIDIRECTIONAL) && (ring_req->sc_data_direction != DMA_TO_DEVICE) && (ring_req->sc_data_direction != DMA_FROM_DEVICE) && (ring_req->sc_data_direction != DMA_NONE)) { pr_debug("invalid parameter data_dir = %d\n", ring_req->sc_data_direction); return ERR_PTR(-EINVAL); } if (ring_req->cmd_len > VSCSIIF_MAX_COMMAND_SIZE) { pr_debug("invalid parameter cmd_len = %d\n", ring_req->cmd_len); return ERR_PTR(-EINVAL); } vir.chn = ring_req->channel; vir.tgt = ring_req->id; vir.lun = ring_req->lun; v2p = scsiback_do_translation(info, &vir); if (!v2p) { pr_debug("the v2p of (chn:%d, tgt:%d, lun:%d) doesn't exist.\n", vir.chn, vir.tgt, vir.lun); return ERR_PTR(-ENODEV); } pending_req = scsiback_get_pend_req(ring, v2p); if (IS_ERR(pending_req)) { kref_put(&v2p->kref, scsiback_free_translation_entry); return ERR_PTR(-ENOMEM); } pending_req->rqid = ring_req->rqid; pending_req->info = info; pending_req->v2p = v2p; pending_req->sc_data_direction = ring_req->sc_data_direction; pending_req->cmd_len = ring_req->cmd_len; memcpy(pending_req->cmnd, ring_req->cmnd, pending_req->cmd_len); return pending_req; } static int scsiback_do_cmd_fn(struct vscsibk_info *info) { struct vscsiif_back_ring *ring = &info->ring; struct vscsiif_request ring_req; struct vscsibk_pend *pending_req; RING_IDX rc, rp; int more_to_do; uint32_t result; rc = ring->req_cons; rp = ring->sring->req_prod; rmb(); /* guest system is accessing ring, too */ if (RING_REQUEST_PROD_OVERFLOW(ring, rp)) { rc = ring->rsp_prod_pvt; pr_warn("Dom%d provided bogus ring requests (%#x - %#x = %u). Halting ring processing\n", info->domid, rp, rc, rp - rc); info->ring_error = 1; return 0; } while ((rc != rp)) { if (RING_REQUEST_CONS_OVERFLOW(ring, rc)) break; RING_COPY_REQUEST(ring, rc, &ring_req); ring->req_cons = ++rc; pending_req = prepare_pending_reqs(info, ring, &ring_req); if (IS_ERR(pending_req)) { switch (PTR_ERR(pending_req)) { case -ENODEV: result = DID_NO_CONNECT; break; default: result = DRIVER_ERROR; break; } scsiback_send_response(info, NULL, result << 24, 0, ring_req.rqid); return 1; } switch (ring_req.act) { case VSCSIIF_ACT_SCSI_CDB: if (scsiback_gnttab_data_map(&ring_req, pending_req)) { scsiback_fast_flush_area(pending_req); scsiback_do_resp_with_sense(NULL, DRIVER_ERROR << 24, 0, pending_req); transport_generic_free_cmd(&pending_req->se_cmd, 0); } else { scsiback_cmd_exec(pending_req); } break; case VSCSIIF_ACT_SCSI_ABORT: scsiback_device_action(pending_req, TMR_ABORT_TASK, ring_req.ref_rqid); break; case VSCSIIF_ACT_SCSI_RESET: scsiback_device_action(pending_req, TMR_LUN_RESET, 0); break; default: pr_err_ratelimited("invalid request\n"); scsiback_do_resp_with_sense(NULL, DRIVER_ERROR << 24, 0, pending_req); transport_generic_free_cmd(&pending_req->se_cmd, 0); break; } /* Yield point for this unbounded loop. */ cond_resched(); } RING_FINAL_CHECK_FOR_REQUESTS(&info->ring, more_to_do); return more_to_do; } static irqreturn_t scsiback_irq_fn(int irq, void *dev_id) { struct vscsibk_info *info = dev_id; if (info->ring_error) return IRQ_HANDLED; while (scsiback_do_cmd_fn(info)) cond_resched(); return IRQ_HANDLED; } static int scsiback_init_sring(struct vscsibk_info *info, grant_ref_t ring_ref, evtchn_port_t evtchn) { void *area; struct vscsiif_sring *sring; int err; if (info->irq) return -1; err = xenbus_map_ring_valloc(info->dev, &ring_ref, 1, &area); if (err) return err; sring = (struct vscsiif_sring *)area; BACK_RING_INIT(&info->ring, sring, PAGE_SIZE); err = bind_interdomain_evtchn_to_irq(info->domid, evtchn); if (err < 0) goto unmap_page; info->irq = err; err = request_threaded_irq(info->irq, NULL, scsiback_irq_fn, IRQF_ONESHOT, "vscsiif-backend", info); if (err) goto free_irq; return 0; free_irq: unbind_from_irqhandler(info->irq, info); info->irq = 0; unmap_page: xenbus_unmap_ring_vfree(info->dev, area); return err; } static int scsiback_map(struct vscsibk_info *info) { struct xenbus_device *dev = info->dev; unsigned int ring_ref, evtchn; int err; err = xenbus_gather(XBT_NIL, dev->otherend, "ring-ref", "%u", &ring_ref, "event-channel", "%u", &evtchn, NULL); if (err) { xenbus_dev_fatal(dev, err, "reading %s ring", dev->otherend); return err; } return scsiback_init_sring(info, ring_ref, evtchn); } /* Check for a translation entry being present */ static struct v2p_entry *scsiback_chk_translation_entry( struct vscsibk_info *info, struct ids_tuple *v) { struct list_head *head = &(info->v2p_entry_lists); struct v2p_entry *entry; list_for_each_entry(entry, head, l) if ((entry->v.chn == v->chn) && (entry->v.tgt == v->tgt) && (entry->v.lun == v->lun)) return entry; return NULL; } /* Add a new translation entry */ static int scsiback_add_translation_entry(struct vscsibk_info *info, char *phy, struct ids_tuple *v) { int err = 0; struct v2p_entry *new; unsigned long flags; char *lunp; unsigned long long unpacked_lun; struct se_lun *se_lun; struct scsiback_tpg *tpg_entry, *tpg = NULL; char *error = "doesn't exist"; lunp = strrchr(phy, ':'); if (!lunp) { pr_err("illegal format of physical device %s\n", phy); return -EINVAL; } *lunp = 0; lunp++; err = kstrtoull(lunp, 10, &unpacked_lun); if (err < 0) { pr_err("lun number not valid: %s\n", lunp); return err; } mutex_lock(&scsiback_mutex); list_for_each_entry(tpg_entry, &scsiback_list, tv_tpg_list) { if (!strcmp(phy, tpg_entry->tport->tport_name) || !strcmp(phy, tpg_entry->param_alias)) { mutex_lock(&tpg_entry->se_tpg.tpg_lun_mutex); hlist_for_each_entry(se_lun, &tpg_entry->se_tpg.tpg_lun_hlist, link) { if (se_lun->unpacked_lun == unpacked_lun) { if (!tpg_entry->tpg_nexus) error = "nexus undefined"; else tpg = tpg_entry; break; } } mutex_unlock(&tpg_entry->se_tpg.tpg_lun_mutex); break; } } if (tpg) { mutex_lock(&tpg->tv_tpg_mutex); tpg->tv_tpg_fe_count++; mutex_unlock(&tpg->tv_tpg_mutex); } mutex_unlock(&scsiback_mutex); if (!tpg) { pr_err("%s:%llu %s\n", phy, unpacked_lun, error); return -ENODEV; } new = kmalloc(sizeof(struct v2p_entry), GFP_KERNEL); if (new == NULL) { err = -ENOMEM; goto out_free; } spin_lock_irqsave(&info->v2p_lock, flags); /* Check double assignment to identical virtual ID */ if (scsiback_chk_translation_entry(info, v)) { pr_warn("Virtual ID is already used. Assignment was not performed.\n"); err = -EEXIST; goto out; } /* Create a new translation entry and add to the list */ kref_init(&new->kref); new->v = *v; new->tpg = tpg; new->lun = unpacked_lun; list_add_tail(&new->l, &info->v2p_entry_lists); out: spin_unlock_irqrestore(&info->v2p_lock, flags); out_free: if (err) { mutex_lock(&tpg->tv_tpg_mutex); tpg->tv_tpg_fe_count--; mutex_unlock(&tpg->tv_tpg_mutex); kfree(new); } return err; } static void __scsiback_del_translation_entry(struct v2p_entry *entry) { list_del(&entry->l); kref_put(&entry->kref, scsiback_free_translation_entry); } /* Delete the translation entry specified */ static int scsiback_del_translation_entry(struct vscsibk_info *info, struct ids_tuple *v) { struct v2p_entry *entry; unsigned long flags; int ret = 0; spin_lock_irqsave(&info->v2p_lock, flags); /* Find out the translation entry specified */ entry = scsiback_chk_translation_entry(info, v); if (entry) __scsiback_del_translation_entry(entry); else ret = -ENOENT; spin_unlock_irqrestore(&info->v2p_lock, flags); return ret; } static void scsiback_do_add_lun(struct vscsibk_info *info, const char *state, char *phy, struct ids_tuple *vir, int try) { struct v2p_entry *entry; unsigned long flags; int err; if (try) { spin_lock_irqsave(&info->v2p_lock, flags); entry = scsiback_chk_translation_entry(info, vir); spin_unlock_irqrestore(&info->v2p_lock, flags); if (entry) return; } if (!scsiback_add_translation_entry(info, phy, vir)) { if (xenbus_printf(XBT_NIL, info->dev->nodename, state, "%d", XenbusStateInitialised)) { pr_err("xenbus_printf error %s\n", state); scsiback_del_translation_entry(info, vir); } } else if (!try) { err = xenbus_printf(XBT_NIL, info->dev->nodename, state, "%d", XenbusStateClosed); if (err) xenbus_dev_error(info->dev, err, "%s: writing %s", __func__, state); } } static void scsiback_do_del_lun(struct vscsibk_info *info, const char *state, struct ids_tuple *vir) { if (!scsiback_del_translation_entry(info, vir)) { if (xenbus_printf(XBT_NIL, info->dev->nodename, state, "%d", XenbusStateClosed)) pr_err("xenbus_printf error %s\n", state); } } #define VSCSIBACK_OP_ADD_OR_DEL_LUN 1 #define VSCSIBACK_OP_UPDATEDEV_STATE 2 static void scsiback_do_1lun_hotplug(struct vscsibk_info *info, int op, char *ent) { int err; struct ids_tuple vir; char *val; int device_state; char phy[VSCSI_NAMELEN]; char str[64]; char state[64]; struct xenbus_device *dev = info->dev; /* read status */ snprintf(state, sizeof(state), "vscsi-devs/%s/state", ent); err = xenbus_scanf(XBT_NIL, dev->nodename, state, "%u", &device_state); if (XENBUS_EXIST_ERR(err)) return; /* physical SCSI device */ snprintf(str, sizeof(str), "vscsi-devs/%s/p-dev", ent); val = xenbus_read(XBT_NIL, dev->nodename, str, NULL); if (IS_ERR(val)) { err = xenbus_printf(XBT_NIL, dev->nodename, state, "%d", XenbusStateClosed); if (err) xenbus_dev_error(info->dev, err, "%s: writing %s", __func__, state); return; } strlcpy(phy, val, VSCSI_NAMELEN); kfree(val); /* virtual SCSI device */ snprintf(str, sizeof(str), "vscsi-devs/%s/v-dev", ent); err = xenbus_scanf(XBT_NIL, dev->nodename, str, "%u:%u:%u:%u", &vir.hst, &vir.chn, &vir.tgt, &vir.lun); if (XENBUS_EXIST_ERR(err)) { err = xenbus_printf(XBT_NIL, dev->nodename, state, "%d", XenbusStateClosed); if (err) xenbus_dev_error(info->dev, err, "%s: writing %s", __func__, state); return; } switch (op) { case VSCSIBACK_OP_ADD_OR_DEL_LUN: switch (device_state) { case XenbusStateInitialising: scsiback_do_add_lun(info, state, phy, &vir, 0); break; case XenbusStateConnected: scsiback_do_add_lun(info, state, phy, &vir, 1); break; case XenbusStateClosing: scsiback_do_del_lun(info, state, &vir); break; default: break; } break; case VSCSIBACK_OP_UPDATEDEV_STATE: if (device_state == XenbusStateInitialised) { /* modify vscsi-devs/dev-x/state */ if (xenbus_printf(XBT_NIL, dev->nodename, state, "%d", XenbusStateConnected)) { pr_err("xenbus_printf error %s\n", str); scsiback_del_translation_entry(info, &vir); xenbus_printf(XBT_NIL, dev->nodename, state, "%d", XenbusStateClosed); } } break; /* When it is necessary, processing is added here. */ default: break; } } static void scsiback_do_lun_hotplug(struct vscsibk_info *info, int op) { int i; char **dir; unsigned int ndir = 0; dir = xenbus_directory(XBT_NIL, info->dev->nodename, "vscsi-devs", &ndir); if (IS_ERR(dir)) return; for (i = 0; i < ndir; i++) scsiback_do_1lun_hotplug(info, op, dir[i]); kfree(dir); } static void scsiback_frontend_changed(struct xenbus_device *dev, enum xenbus_state frontend_state) { struct vscsibk_info *info = dev_get_drvdata(&dev->dev); switch (frontend_state) { case XenbusStateInitialising: break; case XenbusStateInitialised: if (scsiback_map(info)) break; scsiback_do_lun_hotplug(info, VSCSIBACK_OP_ADD_OR_DEL_LUN); xenbus_switch_state(dev, XenbusStateConnected); break; case XenbusStateConnected: scsiback_do_lun_hotplug(info, VSCSIBACK_OP_UPDATEDEV_STATE); if (dev->state == XenbusStateConnected) break; xenbus_switch_state(dev, XenbusStateConnected); break; case XenbusStateClosing: if (info->irq) scsiback_disconnect(info); xenbus_switch_state(dev, XenbusStateClosing); break; case XenbusStateClosed: xenbus_switch_state(dev, XenbusStateClosed); if (xenbus_dev_is_online(dev)) break; /* fall through - if not online */ case XenbusStateUnknown: device_unregister(&dev->dev); break; case XenbusStateReconfiguring: scsiback_do_lun_hotplug(info, VSCSIBACK_OP_ADD_OR_DEL_LUN); xenbus_switch_state(dev, XenbusStateReconfigured); break; default: xenbus_dev_fatal(dev, -EINVAL, "saw state %d at frontend", frontend_state); break; } } /* Release the translation entry specfied */ static void scsiback_release_translation_entry(struct vscsibk_info *info) { struct v2p_entry *entry, *tmp; struct list_head *head = &(info->v2p_entry_lists); unsigned long flags; spin_lock_irqsave(&info->v2p_lock, flags); list_for_each_entry_safe(entry, tmp, head, l) __scsiback_del_translation_entry(entry); spin_unlock_irqrestore(&info->v2p_lock, flags); } static int scsiback_remove(struct xenbus_device *dev) { struct vscsibk_info *info = dev_get_drvdata(&dev->dev); if (info->irq) scsiback_disconnect(info); scsiback_release_translation_entry(info); dev_set_drvdata(&dev->dev, NULL); return 0; } static int scsiback_probe(struct xenbus_device *dev, const struct xenbus_device_id *id) { int err; struct vscsibk_info *info = kzalloc(sizeof(struct vscsibk_info), GFP_KERNEL); pr_debug("%s %p %d\n", __func__, dev, dev->otherend_id); if (!info) { xenbus_dev_fatal(dev, -ENOMEM, "allocating backend structure"); return -ENOMEM; } info->dev = dev; dev_set_drvdata(&dev->dev, info); info->domid = dev->otherend_id; spin_lock_init(&info->ring_lock); info->ring_error = 0; atomic_set(&info->nr_unreplied_reqs, 0); init_waitqueue_head(&info->waiting_to_free); info->dev = dev; info->irq = 0; INIT_LIST_HEAD(&info->v2p_entry_lists); spin_lock_init(&info->v2p_lock); err = xenbus_printf(XBT_NIL, dev->nodename, "feature-sg-grant", "%u", SG_ALL); if (err) xenbus_dev_error(dev, err, "writing feature-sg-grant"); err = xenbus_switch_state(dev, XenbusStateInitWait); if (err) goto fail; return 0; fail: pr_warn("%s failed\n", __func__); scsiback_remove(dev); return err; } static char *scsiback_dump_proto_id(struct scsiback_tport *tport) { switch (tport->tport_proto_id) { case SCSI_PROTOCOL_SAS: return "SAS"; case SCSI_PROTOCOL_FCP: return "FCP"; case SCSI_PROTOCOL_ISCSI: return "iSCSI"; default: break; } return "Unknown"; } static char *scsiback_get_fabric_wwn(struct se_portal_group *se_tpg) { struct scsiback_tpg *tpg = container_of(se_tpg, struct scsiback_tpg, se_tpg); struct scsiback_tport *tport = tpg->tport; return &tport->tport_name[0]; } static u16 scsiback_get_tag(struct se_portal_group *se_tpg) { struct scsiback_tpg *tpg = container_of(se_tpg, struct scsiback_tpg, se_tpg); return tpg->tport_tpgt; } static struct se_wwn * scsiback_make_tport(struct target_fabric_configfs *tf, struct config_group *group, const char *name) { struct scsiback_tport *tport; char *ptr; u64 wwpn = 0; int off = 0; tport = kzalloc(sizeof(struct scsiback_tport), GFP_KERNEL); if (!tport) return ERR_PTR(-ENOMEM); tport->tport_wwpn = wwpn; /* * Determine the emulated Protocol Identifier and Target Port Name * based on the incoming configfs directory name. */ ptr = strstr(name, "naa."); if (ptr) { tport->tport_proto_id = SCSI_PROTOCOL_SAS; goto check_len; } ptr = strstr(name, "fc."); if (ptr) { tport->tport_proto_id = SCSI_PROTOCOL_FCP; off = 3; /* Skip over "fc." */ goto check_len; } ptr = strstr(name, "iqn."); if (ptr) { tport->tport_proto_id = SCSI_PROTOCOL_ISCSI; goto check_len; } pr_err("Unable to locate prefix for emulated Target Port: %s\n", name); kfree(tport); return ERR_PTR(-EINVAL); check_len: if (strlen(name) >= VSCSI_NAMELEN) { pr_err("Emulated %s Address: %s, exceeds max: %d\n", name, scsiback_dump_proto_id(tport), VSCSI_NAMELEN); kfree(tport); return ERR_PTR(-EINVAL); } snprintf(&tport->tport_name[0], VSCSI_NAMELEN, "%s", &name[off]); pr_debug("Allocated emulated Target %s Address: %s\n", scsiback_dump_proto_id(tport), name); return &tport->tport_wwn; } static void scsiback_drop_tport(struct se_wwn *wwn) { struct scsiback_tport *tport = container_of(wwn, struct scsiback_tport, tport_wwn); pr_debug("Deallocating emulated Target %s Address: %s\n", scsiback_dump_proto_id(tport), tport->tport_name); kfree(tport); } static u32 scsiback_tpg_get_inst_index(struct se_portal_group *se_tpg) { return 1; } static int scsiback_check_stop_free(struct se_cmd *se_cmd) { return transport_generic_free_cmd(se_cmd, 0); } static void scsiback_release_cmd(struct se_cmd *se_cmd) { target_free_tag(se_cmd->se_sess, se_cmd); } static u32 scsiback_sess_get_index(struct se_session *se_sess) { return 0; } static int scsiback_write_pending(struct se_cmd *se_cmd) { /* Go ahead and process the write immediately */ target_execute_cmd(se_cmd); return 0; } static void scsiback_set_default_node_attrs(struct se_node_acl *nacl) { } static int scsiback_get_cmd_state(struct se_cmd *se_cmd) { return 0; } static int scsiback_queue_data_in(struct se_cmd *se_cmd) { struct vscsibk_pend *pending_req = container_of(se_cmd, struct vscsibk_pend, se_cmd); pending_req->result = SAM_STAT_GOOD; scsiback_cmd_done(pending_req); return 0; } static int scsiback_queue_status(struct se_cmd *se_cmd) { struct vscsibk_pend *pending_req = container_of(se_cmd, struct vscsibk_pend, se_cmd); if (se_cmd->sense_buffer && ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) || (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE))) pending_req->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION; else pending_req->result = se_cmd->scsi_status; scsiback_cmd_done(pending_req); return 0; } static void scsiback_queue_tm_rsp(struct se_cmd *se_cmd) { struct vscsibk_pend *pending_req = container_of(se_cmd, struct vscsibk_pend, se_cmd); complete(&pending_req->tmr_done); } static void scsiback_aborted_task(struct se_cmd *se_cmd) { } static ssize_t scsiback_tpg_param_alias_show(struct config_item *item, char *page) { struct se_portal_group *se_tpg = param_to_tpg(item); struct scsiback_tpg *tpg = container_of(se_tpg, struct scsiback_tpg, se_tpg); ssize_t rb; mutex_lock(&tpg->tv_tpg_mutex); rb = snprintf(page, PAGE_SIZE, "%s\n", tpg->param_alias); mutex_unlock(&tpg->tv_tpg_mutex); return rb; } static ssize_t scsiback_tpg_param_alias_store(struct config_item *item, const char *page, size_t count) { struct se_portal_group *se_tpg = param_to_tpg(item); struct scsiback_tpg *tpg = container_of(se_tpg, struct scsiback_tpg, se_tpg); int len; if (strlen(page) >= VSCSI_NAMELEN) { pr_err("param alias: %s, exceeds max: %d\n", page, VSCSI_NAMELEN); return -EINVAL; } mutex_lock(&tpg->tv_tpg_mutex); len = snprintf(tpg->param_alias, VSCSI_NAMELEN, "%s", page); if (tpg->param_alias[len - 1] == '\n') tpg->param_alias[len - 1] = '\0'; mutex_unlock(&tpg->tv_tpg_mutex); return count; } CONFIGFS_ATTR(scsiback_tpg_param_, alias); static struct configfs_attribute *scsiback_param_attrs[] = { &scsiback_tpg_param_attr_alias, NULL, }; static int scsiback_alloc_sess_cb(struct se_portal_group *se_tpg, struct se_session *se_sess, void *p) { struct scsiback_tpg *tpg = container_of(se_tpg, struct scsiback_tpg, se_tpg); tpg->tpg_nexus = p; return 0; } static int scsiback_make_nexus(struct scsiback_tpg *tpg, const char *name) { struct scsiback_nexus *tv_nexus; int ret = 0; mutex_lock(&tpg->tv_tpg_mutex); if (tpg->tpg_nexus) { pr_debug("tpg->tpg_nexus already exists\n"); ret = -EEXIST; goto out_unlock; } tv_nexus = kzalloc(sizeof(struct scsiback_nexus), GFP_KERNEL); if (!tv_nexus) { ret = -ENOMEM; goto out_unlock; } tv_nexus->tvn_se_sess = target_setup_session(&tpg->se_tpg, VSCSI_DEFAULT_SESSION_TAGS, sizeof(struct vscsibk_pend), TARGET_PROT_NORMAL, name, tv_nexus, scsiback_alloc_sess_cb); if (IS_ERR(tv_nexus->tvn_se_sess)) { kfree(tv_nexus); ret = -ENOMEM; goto out_unlock; } out_unlock: mutex_unlock(&tpg->tv_tpg_mutex); return ret; } static int scsiback_drop_nexus(struct scsiback_tpg *tpg) { struct se_session *se_sess; struct scsiback_nexus *tv_nexus; mutex_lock(&tpg->tv_tpg_mutex); tv_nexus = tpg->tpg_nexus; if (!tv_nexus) { mutex_unlock(&tpg->tv_tpg_mutex); return -ENODEV; } se_sess = tv_nexus->tvn_se_sess; if (!se_sess) { mutex_unlock(&tpg->tv_tpg_mutex); return -ENODEV; } if (tpg->tv_tpg_port_count != 0) { mutex_unlock(&tpg->tv_tpg_mutex); pr_err("Unable to remove xen-pvscsi I_T Nexus with active TPG port count: %d\n", tpg->tv_tpg_port_count); return -EBUSY; } if (tpg->tv_tpg_fe_count != 0) { mutex_unlock(&tpg->tv_tpg_mutex); pr_err("Unable to remove xen-pvscsi I_T Nexus with active TPG frontend count: %d\n", tpg->tv_tpg_fe_count); return -EBUSY; } pr_debug("Removing I_T Nexus to emulated %s Initiator Port: %s\n", scsiback_dump_proto_id(tpg->tport), tv_nexus->tvn_se_sess->se_node_acl->initiatorname); /* * Release the SCSI I_T Nexus to the emulated xen-pvscsi Target Port */ target_remove_session(se_sess); tpg->tpg_nexus = NULL; mutex_unlock(&tpg->tv_tpg_mutex); kfree(tv_nexus); return 0; } static ssize_t scsiback_tpg_nexus_show(struct config_item *item, char *page) { struct se_portal_group *se_tpg = to_tpg(item); struct scsiback_tpg *tpg = container_of(se_tpg, struct scsiback_tpg, se_tpg); struct scsiback_nexus *tv_nexus; ssize_t ret; mutex_lock(&tpg->tv_tpg_mutex); tv_nexus = tpg->tpg_nexus; if (!tv_nexus) { mutex_unlock(&tpg->tv_tpg_mutex); return -ENODEV; } ret = snprintf(page, PAGE_SIZE, "%s\n", tv_nexus->tvn_se_sess->se_node_acl->initiatorname); mutex_unlock(&tpg->tv_tpg_mutex); return ret; } static ssize_t scsiback_tpg_nexus_store(struct config_item *item, const char *page, size_t count) { struct se_portal_group *se_tpg = to_tpg(item); struct scsiback_tpg *tpg = container_of(se_tpg, struct scsiback_tpg, se_tpg); struct scsiback_tport *tport_wwn = tpg->tport; unsigned char i_port[VSCSI_NAMELEN], *ptr, *port_ptr; int ret; /* * Shutdown the active I_T nexus if 'NULL' is passed. */ if (!strncmp(page, "NULL", 4)) { ret = scsiback_drop_nexus(tpg); return (!ret) ? count : ret; } /* * Otherwise make sure the passed virtual Initiator port WWN matches * the fabric protocol_id set in scsiback_make_tport(), and call * scsiback_make_nexus(). */ if (strlen(page) >= VSCSI_NAMELEN) { pr_err("Emulated NAA Sas Address: %s, exceeds max: %d\n", page, VSCSI_NAMELEN); return -EINVAL; } snprintf(&i_port[0], VSCSI_NAMELEN, "%s", page); ptr = strstr(i_port, "naa."); if (ptr) { if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) { pr_err("Passed SAS Initiator Port %s does not match target port protoid: %s\n", i_port, scsiback_dump_proto_id(tport_wwn)); return -EINVAL; } port_ptr = &i_port[0]; goto check_newline; } ptr = strstr(i_port, "fc."); if (ptr) { if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) { pr_err("Passed FCP Initiator Port %s does not match target port protoid: %s\n", i_port, scsiback_dump_proto_id(tport_wwn)); return -EINVAL; } port_ptr = &i_port[3]; /* Skip over "fc." */ goto check_newline; } ptr = strstr(i_port, "iqn."); if (ptr) { if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) { pr_err("Passed iSCSI Initiator Port %s does not match target port protoid: %s\n", i_port, scsiback_dump_proto_id(tport_wwn)); return -EINVAL; } port_ptr = &i_port[0]; goto check_newline; } pr_err("Unable to locate prefix for emulated Initiator Port: %s\n", i_port); return -EINVAL; /* * Clear any trailing newline for the NAA WWN */ check_newline: if (i_port[strlen(i_port) - 1] == '\n') i_port[strlen(i_port) - 1] = '\0'; ret = scsiback_make_nexus(tpg, port_ptr); if (ret < 0) return ret; return count; } CONFIGFS_ATTR(scsiback_tpg_, nexus); static struct configfs_attribute *scsiback_tpg_attrs[] = { &scsiback_tpg_attr_nexus, NULL, }; static ssize_t scsiback_wwn_version_show(struct config_item *item, char *page) { return sprintf(page, "xen-pvscsi fabric module %s on %s/%s on " UTS_RELEASE"\n", VSCSI_VERSION, utsname()->sysname, utsname()->machine); } CONFIGFS_ATTR_RO(scsiback_wwn_, version); static struct configfs_attribute *scsiback_wwn_attrs[] = { &scsiback_wwn_attr_version, NULL, }; static int scsiback_port_link(struct se_portal_group *se_tpg, struct se_lun *lun) { struct scsiback_tpg *tpg = container_of(se_tpg, struct scsiback_tpg, se_tpg); mutex_lock(&tpg->tv_tpg_mutex); tpg->tv_tpg_port_count++; mutex_unlock(&tpg->tv_tpg_mutex); return 0; } static void scsiback_port_unlink(struct se_portal_group *se_tpg, struct se_lun *lun) { struct scsiback_tpg *tpg = container_of(se_tpg, struct scsiback_tpg, se_tpg); mutex_lock(&tpg->tv_tpg_mutex); tpg->tv_tpg_port_count--; mutex_unlock(&tpg->tv_tpg_mutex); } static struct se_portal_group * scsiback_make_tpg(struct se_wwn *wwn, const char *name) { struct scsiback_tport *tport = container_of(wwn, struct scsiback_tport, tport_wwn); struct scsiback_tpg *tpg; u16 tpgt; int ret; if (strstr(name, "tpgt_") != name) return ERR_PTR(-EINVAL); ret = kstrtou16(name + 5, 10, &tpgt); if (ret) return ERR_PTR(ret); tpg = kzalloc(sizeof(struct scsiback_tpg), GFP_KERNEL); if (!tpg) return ERR_PTR(-ENOMEM); mutex_init(&tpg->tv_tpg_mutex); INIT_LIST_HEAD(&tpg->tv_tpg_list); INIT_LIST_HEAD(&tpg->info_list); tpg->tport = tport; tpg->tport_tpgt = tpgt; ret = core_tpg_register(wwn, &tpg->se_tpg, tport->tport_proto_id); if (ret < 0) { kfree(tpg); return NULL; } mutex_lock(&scsiback_mutex); list_add_tail(&tpg->tv_tpg_list, &scsiback_list); mutex_unlock(&scsiback_mutex); return &tpg->se_tpg; } static void scsiback_drop_tpg(struct se_portal_group *se_tpg) { struct scsiback_tpg *tpg = container_of(se_tpg, struct scsiback_tpg, se_tpg); mutex_lock(&scsiback_mutex); list_del(&tpg->tv_tpg_list); mutex_unlock(&scsiback_mutex); /* * Release the virtual I_T Nexus for this xen-pvscsi TPG */ scsiback_drop_nexus(tpg); /* * Deregister the se_tpg from TCM. */ core_tpg_deregister(se_tpg); kfree(tpg); } static int scsiback_check_true(struct se_portal_group *se_tpg) { return 1; } static int scsiback_check_false(struct se_portal_group *se_tpg) { return 0; } static const struct target_core_fabric_ops scsiback_ops = { .module = THIS_MODULE, .fabric_name = "xen-pvscsi", .tpg_get_wwn = scsiback_get_fabric_wwn, .tpg_get_tag = scsiback_get_tag, .tpg_check_demo_mode = scsiback_check_true, .tpg_check_demo_mode_cache = scsiback_check_true, .tpg_check_demo_mode_write_protect = scsiback_check_false, .tpg_check_prod_mode_write_protect = scsiback_check_false, .tpg_get_inst_index = scsiback_tpg_get_inst_index, .check_stop_free = scsiback_check_stop_free, .release_cmd = scsiback_release_cmd, .sess_get_index = scsiback_sess_get_index, .sess_get_initiator_sid = NULL, .write_pending = scsiback_write_pending, .set_default_node_attributes = scsiback_set_default_node_attrs, .get_cmd_state = scsiback_get_cmd_state, .queue_data_in = scsiback_queue_data_in, .queue_status = scsiback_queue_status, .queue_tm_rsp = scsiback_queue_tm_rsp, .aborted_task = scsiback_aborted_task, /* * Setup callers for generic logic in target_core_fabric_configfs.c */ .fabric_make_wwn = scsiback_make_tport, .fabric_drop_wwn = scsiback_drop_tport, .fabric_make_tpg = scsiback_make_tpg, .fabric_drop_tpg = scsiback_drop_tpg, .fabric_post_link = scsiback_port_link, .fabric_pre_unlink = scsiback_port_unlink, .tfc_wwn_attrs = scsiback_wwn_attrs, .tfc_tpg_base_attrs = scsiback_tpg_attrs, .tfc_tpg_param_attrs = scsiback_param_attrs, }; static const struct xenbus_device_id scsiback_ids[] = { { "vscsi" }, { "" } }; static struct xenbus_driver scsiback_driver = { .ids = scsiback_ids, .probe = scsiback_probe, .remove = scsiback_remove, .otherend_changed = scsiback_frontend_changed }; static int __init scsiback_init(void) { int ret; if (!xen_domain()) return -ENODEV; pr_debug("xen-pvscsi: fabric module %s on %s/%s on "UTS_RELEASE"\n", VSCSI_VERSION, utsname()->sysname, utsname()->machine); ret = xenbus_register_backend(&scsiback_driver); if (ret) goto out; ret = target_register_template(&scsiback_ops); if (ret) goto out_unregister_xenbus; return 0; out_unregister_xenbus: xenbus_unregister_driver(&scsiback_driver); out: pr_err("%s: error %d\n", __func__, ret); return ret; } static void __exit scsiback_exit(void) { struct page *page; while (free_pages_num) { if (get_free_page(&page)) BUG(); gnttab_free_pages(1, &page); } target_unregister_template(&scsiback_ops); xenbus_unregister_driver(&scsiback_driver); } module_init(scsiback_init); module_exit(scsiback_exit); MODULE_DESCRIPTION("Xen SCSI backend driver"); MODULE_LICENSE("Dual BSD/GPL"); MODULE_ALIAS("xen-backend:vscsi"); MODULE_AUTHOR("Juergen Gross ");