diff options
Diffstat (limited to 'drivers/xen/xen-scsiback.c')
| -rw-r--r-- | drivers/xen/xen-scsiback.c | 361 |
1 files changed, 185 insertions, 176 deletions
diff --git a/drivers/xen/xen-scsiback.c b/drivers/xen/xen-scsiback.c index ad4eb1024d1f..ff932624eaad 100644 --- a/drivers/xen/xen-scsiback.c +++ b/drivers/xen/xen-scsiback.c @@ -141,6 +141,8 @@ struct scsiback_tmr { wait_queue_head_t tmr_wait; }; +#define VSCSI_DEFAULT_SESSION_TAGS 128 + struct scsiback_nexus { /* Pointer to TCM session for I_T Nexus */ struct se_session *tvn_se_sess; @@ -190,7 +192,6 @@ 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 struct kmem_cache *scsiback_cachep; static DEFINE_SPINLOCK(free_pages_lock); static int free_pages_num; static LIST_HEAD(scsiback_free_pages); @@ -321,11 +322,11 @@ static void scsiback_free_translation_entry(struct kref *kref) kfree(entry); } -static void scsiback_do_resp_with_sense(char *sense_buffer, int32_t result, - uint32_t resid, struct vscsibk_pend *pending_req) +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; - struct vscsibk_info *info = pending_req->info; int notify; struct scsi_sense_hdr sshdr; unsigned long flags; @@ -337,7 +338,7 @@ static void scsiback_do_resp_with_sense(char *sense_buffer, int32_t result, info->ring.rsp_prod_pvt++; ring_res->rslt = result; - ring_res->rqid = pending_req->rqid; + ring_res->rqid = rqid; if (sense_buffer != NULL && scsi_normalize_sense(sense_buffer, VSCSIIF_SENSE_BUFFERSIZE, @@ -357,6 +358,13 @@ static void scsiback_do_resp_with_sense(char *sense_buffer, int32_t result, 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, @@ -380,6 +388,12 @@ static void scsiback_cmd_done(struct vscsibk_pend *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) @@ -388,16 +402,12 @@ static void scsiback_cmd_exec(struct vscsibk_pend *pending_req) struct se_session *sess = pending_req->v2p->tpg->tpg_nexus->tvn_se_sess; int rc; - memset(pending_req->sense_buffer, 0, VSCSIIF_SENSE_BUFFERSIZE); - - memset(se_cmd, 0, sizeof(*se_cmd)); - 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, 0, + pending_req->sc_data_direction, TARGET_SCF_ACK_KREF, pending_req->sgl, pending_req->n_sg, NULL, 0, NULL, 0); if (rc < 0) { @@ -586,45 +596,40 @@ static void scsiback_disconnect(struct vscsibk_info *info) static void scsiback_device_action(struct vscsibk_pend *pending_req, enum tcm_tmreq_table act, int tag) { - int rc, err = FAILED; struct scsiback_tpg *tpg = pending_req->v2p->tpg; + struct scsiback_nexus *nexus = tpg->tpg_nexus; struct se_cmd *se_cmd = &pending_req->se_cmd; struct scsiback_tmr *tmr; + u64 unpacked_lun = pending_req->v2p->lun; + int rc, err = FAILED; tmr = kzalloc(sizeof(struct scsiback_tmr), GFP_KERNEL); - if (!tmr) - goto out; + if (!tmr) { + target_put_sess_cmd(se_cmd); + goto err; + } init_waitqueue_head(&tmr->tmr_wait); - transport_init_se_cmd(se_cmd, tpg->se_tpg.se_tpg_tfo, - tpg->tpg_nexus->tvn_se_sess, 0, DMA_NONE, TCM_SIMPLE_TAG, - &pending_req->sense_buffer[0]); - - rc = core_tmr_alloc_req(se_cmd, tmr, act, GFP_KERNEL); - if (rc < 0) - goto out; - - se_cmd->se_tmr_req->ref_task_tag = tag; + rc = target_submit_tmr(&pending_req->se_cmd, nexus->tvn_se_sess, + &pending_req->sense_buffer[0], + unpacked_lun, tmr, act, GFP_KERNEL, + tag, TARGET_SCF_ACK_KREF); + if (rc) + goto err; - if (transport_lookup_tmr_lun(se_cmd, pending_req->v2p->lun) < 0) - goto out; - - transport_generic_handle_tmr(se_cmd); wait_event(tmr->tmr_wait, atomic_read(&tmr->tmr_complete)); err = (se_cmd->se_tmr_req->response == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED; -out: - if (tmr) { - transport_generic_free_cmd(&pending_req->se_cmd, 1); + scsiback_do_resp_with_sense(NULL, err, 0, pending_req); + transport_generic_free_cmd(&pending_req->se_cmd, 1); + return; +err: + if (tmr) kfree(tmr); - } - scsiback_do_resp_with_sense(NULL, err, 0, pending_req); - - kmem_cache_free(scsiback_cachep, pending_req); } /* @@ -653,15 +658,53 @@ out: return entry; } -static int prepare_pending_reqs(struct vscsibk_info *info, - struct vscsiif_request *ring_req, - struct vscsibk_pend *pending_req) +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, i; + + tag = percpu_ida_alloc(&se_sess->sess_tag_pool, TASK_RUNNING); + 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; + + 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; - pending_req->rqid = ring_req->rqid; - pending_req->info = info; + /* 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; @@ -669,33 +712,24 @@ static int prepare_pending_reqs(struct vscsibk_info *info, v2p = scsiback_do_translation(info, &vir); if (!v2p) { - pending_req->v2p = NULL; pr_debug("the v2p of (chn:%d, tgt:%d, lun:%d) doesn't exist.\n", - vir.chn, vir.tgt, vir.lun); - return -ENODEV; + vir.chn, vir.tgt, vir.lun); + return ERR_PTR(-ENODEV); } - pending_req->v2p = v2p; - /* request range check from frontend */ - pending_req->sc_data_direction = ring_req->sc_data_direction; - if ((pending_req->sc_data_direction != DMA_BIDIRECTIONAL) && - (pending_req->sc_data_direction != DMA_TO_DEVICE) && - (pending_req->sc_data_direction != DMA_FROM_DEVICE) && - (pending_req->sc_data_direction != DMA_NONE)) { - pr_debug("invalid parameter data_dir = %d\n", - pending_req->sc_data_direction); - return -EINVAL; + 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; - if (pending_req->cmd_len > VSCSIIF_MAX_COMMAND_SIZE) { - pr_debug("invalid parameter cmd_len = %d\n", - pending_req->cmd_len); - return -EINVAL; - } memcpy(pending_req->cmnd, ring_req->cmnd, pending_req->cmd_len); - return 0; + return pending_req; } static int scsiback_do_cmd_fn(struct vscsibk_info *info) @@ -704,7 +738,7 @@ static int scsiback_do_cmd_fn(struct vscsibk_info *info) struct vscsiif_request ring_req; struct vscsibk_pend *pending_req; RING_IDX rc, rp; - int err, more_to_do; + int more_to_do; uint32_t result; rc = ring->req_cons; @@ -722,16 +756,13 @@ static int scsiback_do_cmd_fn(struct vscsibk_info *info) while ((rc != rp)) { if (RING_REQUEST_CONS_OVERFLOW(ring, rc)) break; - pending_req = kmem_cache_alloc(scsiback_cachep, GFP_KERNEL); - if (!pending_req) - return 1; RING_COPY_REQUEST(ring, rc, &ring_req); ring->req_cons = ++rc; - err = prepare_pending_reqs(info, &ring_req, pending_req); - if (err) { - switch (err) { + 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; @@ -739,9 +770,8 @@ static int scsiback_do_cmd_fn(struct vscsibk_info *info) result = DRIVER_ERROR; break; } - scsiback_do_resp_with_sense(NULL, result << 24, 0, - pending_req); - kmem_cache_free(scsiback_cachep, pending_req); + scsiback_send_response(info, NULL, result << 24, 0, + ring_req.rqid); return 1; } @@ -750,8 +780,8 @@ static int scsiback_do_cmd_fn(struct vscsibk_info *info) 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); - kmem_cache_free(scsiback_cachep, pending_req); + DRIVER_ERROR << 24, 0, pending_req); + transport_generic_free_cmd(&pending_req->se_cmd, 0); } else { scsiback_cmd_exec(pending_req); } @@ -765,9 +795,9 @@ static int scsiback_do_cmd_fn(struct vscsibk_info *info) break; default: pr_err_ratelimited("invalid request\n"); - scsiback_do_resp_with_sense(NULL, DRIVER_ERROR << 24, - 0, pending_req); - kmem_cache_free(scsiback_cachep, pending_req); + scsiback_do_resp_with_sense(NULL, DRIVER_ERROR << 24, 0, + pending_req); + transport_generic_free_cmd(&pending_req->se_cmd, 0); break; } @@ -849,15 +879,31 @@ static int scsiback_map(struct vscsibk_info *info) } /* + 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 *entry; struct v2p_entry *new; - struct list_head *head = &(info->v2p_entry_lists); unsigned long flags; char *lunp; unsigned long long unpacked_lun; @@ -917,15 +963,10 @@ static int scsiback_add_translation_entry(struct vscsibk_info *info, spin_lock_irqsave(&info->v2p_lock, flags); /* Check double assignment to identical virtual ID */ - list_for_each_entry(entry, head, l) { - if ((entry->v.chn == v->chn) && - (entry->v.tgt == v->tgt) && - (entry->v.lun == v->lun)) { - pr_warn("Virtual ID is already used. Assignment was not performed.\n"); - err = -EEXIST; - goto out; - } - + 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 */ @@ -933,18 +974,18 @@ static int scsiback_add_translation_entry(struct vscsibk_info *info, new->v = *v; new->tpg = tpg; new->lun = unpacked_lun; - list_add_tail(&new->l, head); + list_add_tail(&new->l, &info->v2p_entry_lists); out: spin_unlock_irqrestore(&info->v2p_lock, flags); out_free: - mutex_lock(&tpg->tv_tpg_mutex); - tpg->tv_tpg_fe_count--; - mutex_unlock(&tpg->tv_tpg_mutex); - - if (err) + if (err) { + mutex_lock(&tpg->tv_tpg_mutex); + tpg->tv_tpg_fe_count--; + mutex_unlock(&tpg->tv_tpg_mutex); kfree(new); + } return err; } @@ -956,39 +997,40 @@ static void __scsiback_del_translation_entry(struct v2p_entry *entry) } /* - Delete the translation entry specfied + Delete the translation entry specified */ static int scsiback_del_translation_entry(struct vscsibk_info *info, struct ids_tuple *v) { struct v2p_entry *entry; - struct list_head *head = &(info->v2p_entry_lists); unsigned long flags; + int ret = 0; spin_lock_irqsave(&info->v2p_lock, flags); /* Find out the translation entry specified */ - list_for_each_entry(entry, head, l) { - if ((entry->v.chn == v->chn) && - (entry->v.tgt == v->tgt) && - (entry->v.lun == v->lun)) { - goto found; - } - } - - spin_unlock_irqrestore(&info->v2p_lock, flags); - return 1; - -found: - /* Delete the translation entry specfied */ - __scsiback_del_translation_entry(entry); + 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 0; + 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; + + 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)) { @@ -1341,24 +1383,20 @@ static u32 scsiback_tpg_get_inst_index(struct se_portal_group *se_tpg) static int scsiback_check_stop_free(struct se_cmd *se_cmd) { - /* - * Do not release struct se_cmd's containing a valid TMR pointer. - * These will be released directly in scsiback_device_action() - * with transport_generic_free_cmd(). - */ - if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB) - return 0; - - transport_generic_free_cmd(se_cmd, 0); - return 1; + return transport_generic_free_cmd(se_cmd, 0); } static void scsiback_release_cmd(struct se_cmd *se_cmd) { - struct vscsibk_pend *pending_req = container_of(se_cmd, - struct vscsibk_pend, se_cmd); + struct se_session *se_sess = se_cmd->se_sess; + struct se_tmr_req *se_tmr = se_cmd->se_tmr_req; - kmem_cache_free(scsiback_cachep, pending_req); + if (se_tmr && se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB) { + struct scsiback_tmr *tmr = se_tmr->fabric_tmr_ptr; + kfree(tmr); + } + + percpu_ida_free(&se_sess->sess_tag_pool, se_cmd->map_tag); } static int scsiback_shutdown_session(struct se_session *se_sess) @@ -1482,61 +1520,49 @@ static struct configfs_attribute *scsiback_param_attrs[] = { 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 se_portal_group *se_tpg; - struct se_session *se_sess; struct scsiback_nexus *tv_nexus; + int ret = 0; mutex_lock(&tpg->tv_tpg_mutex); if (tpg->tpg_nexus) { - mutex_unlock(&tpg->tv_tpg_mutex); pr_debug("tpg->tpg_nexus already exists\n"); - return -EEXIST; + ret = -EEXIST; + goto out_unlock; } - se_tpg = &tpg->se_tpg; tv_nexus = kzalloc(sizeof(struct scsiback_nexus), GFP_KERNEL); if (!tv_nexus) { - mutex_unlock(&tpg->tv_tpg_mutex); - return -ENOMEM; + ret = -ENOMEM; + goto out_unlock; } - /* - * Initialize the struct se_session pointer - */ - tv_nexus->tvn_se_sess = transport_init_session(TARGET_PROT_NORMAL); + + tv_nexus->tvn_se_sess = target_alloc_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)) { - mutex_unlock(&tpg->tv_tpg_mutex); kfree(tv_nexus); - return -ENOMEM; - } - se_sess = tv_nexus->tvn_se_sess; - /* - * Since we are running in 'demo mode' this call with generate a - * struct se_node_acl for the scsiback struct se_portal_group with - * the SCSI Initiator port name of the passed configfs group 'name'. - */ - tv_nexus->tvn_se_sess->se_node_acl = core_tpg_check_initiator_node_acl( - se_tpg, (unsigned char *)name); - if (!tv_nexus->tvn_se_sess->se_node_acl) { - mutex_unlock(&tpg->tv_tpg_mutex); - pr_debug("core_tpg_check_initiator_node_acl() failed for %s\n", - name); - goto out; + ret = -ENOMEM; + goto out_unlock; } - /* Now register the TCM pvscsi virtual I_T Nexus as active. */ - transport_register_session(se_tpg, tv_nexus->tvn_se_sess->se_node_acl, - tv_nexus->tvn_se_sess, tv_nexus); - tpg->tpg_nexus = tv_nexus; +out_unlock: mutex_unlock(&tpg->tv_tpg_mutex); - return 0; - -out: - transport_free_session(se_sess); - kfree(tv_nexus); - return -ENOMEM; + return ret; } static int scsiback_drop_nexus(struct scsiback_tpg *tpg) @@ -1854,16 +1880,6 @@ static struct xenbus_driver scsiback_driver = { .otherend_changed = scsiback_frontend_changed }; -static void scsiback_init_pend(void *p) -{ - struct vscsibk_pend *pend = p; - int i; - - memset(pend, 0, sizeof(*pend)); - for (i = 0; i < VSCSI_MAX_GRANTS; i++) - pend->grant_handles[i] = SCSIBACK_INVALID_HANDLE; -} - static int __init scsiback_init(void) { int ret; @@ -1874,14 +1890,9 @@ static int __init scsiback_init(void) pr_debug("xen-pvscsi: fabric module %s on %s/%s on "UTS_RELEASE"\n", VSCSI_VERSION, utsname()->sysname, utsname()->machine); - scsiback_cachep = kmem_cache_create("vscsiif_cache", - sizeof(struct vscsibk_pend), 0, 0, scsiback_init_pend); - if (!scsiback_cachep) - return -ENOMEM; - ret = xenbus_register_backend(&scsiback_driver); if (ret) - goto out_cache_destroy; + goto out; ret = target_register_template(&scsiback_ops); if (ret) @@ -1891,8 +1902,7 @@ static int __init scsiback_init(void) out_unregister_xenbus: xenbus_unregister_driver(&scsiback_driver); -out_cache_destroy: - kmem_cache_destroy(scsiback_cachep); +out: pr_err("%s: error %d\n", __func__, ret); return ret; } @@ -1908,7 +1918,6 @@ static void __exit scsiback_exit(void) } target_unregister_template(&scsiback_ops); xenbus_unregister_driver(&scsiback_driver); - kmem_cache_destroy(scsiback_cachep); } module_init(scsiback_init); |