1 /*******************************************************************************
2 * Vhost kernel TCM fabric driver for virtio SCSI initiators
4 * (C) Copyright 2010-2013 Datera, Inc.
5 * (C) Copyright 2010-2012 IBM Corp.
7 * Licensed to the Linux Foundation under the General Public License (GPL) version 2.
9 * Authors: Nicholas A. Bellinger <nab@daterainc.com>
10 * Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
22 ****************************************************************************/
24 #include <linux/module.h>
25 #include <linux/moduleparam.h>
26 #include <generated/utsrelease.h>
27 #include <linux/utsname.h>
28 #include <linux/init.h>
29 #include <linux/slab.h>
30 #include <linux/kthread.h>
31 #include <linux/types.h>
32 #include <linux/string.h>
33 #include <linux/configfs.h>
34 #include <linux/ctype.h>
35 #include <linux/compat.h>
36 #include <linux/eventfd.h>
38 #include <linux/miscdevice.h>
39 #include <asm/unaligned.h>
40 #include <scsi/scsi.h>
41 #include <scsi/scsi_tcq.h>
42 #include <target/target_core_base.h>
43 #include <target/target_core_fabric.h>
44 #include <target/target_core_fabric_configfs.h>
45 #include <target/target_core_configfs.h>
46 #include <target/configfs_macros.h>
47 #include <linux/vhost.h>
48 #include <linux/virtio_scsi.h>
49 #include <linux/llist.h>
50 #include <linux/bitmap.h>
51 #include <linux/percpu_ida.h>
55 #define TCM_VHOST_VERSION "v0.1"
56 #define TCM_VHOST_NAMELEN 256
57 #define TCM_VHOST_MAX_CDB_SIZE 32
58 #define TCM_VHOST_DEFAULT_TAGS 256
59 #define TCM_VHOST_PREALLOC_SGLS 2048
60 #define TCM_VHOST_PREALLOC_PAGES 2048
62 struct vhost_scsi_inflight {
63 /* Wait for the flush operation to finish */
64 struct completion comp;
65 /* Refcount for the inflight reqs */
69 struct tcm_vhost_cmd {
70 /* Descriptor from vhost_get_vq_desc() for virt_queue segment */
72 /* virtio-scsi initiator task attribute */
74 /* virtio-scsi initiator data direction */
75 enum dma_data_direction tvc_data_direction;
76 /* Expected data transfer length from virtio-scsi header */
78 /* The Tag from include/linux/virtio_scsi.h:struct virtio_scsi_cmd_req */
80 /* The number of scatterlists associated with this cmd */
82 /* Saved unpacked SCSI LUN for tcm_vhost_submission_work() */
84 /* Pointer to the SGL formatted memory from virtio-scsi */
85 struct scatterlist *tvc_sgl;
86 struct page **tvc_upages;
87 /* Pointer to response */
88 struct virtio_scsi_cmd_resp __user *tvc_resp;
89 /* Pointer to vhost_scsi for our device */
90 struct vhost_scsi *tvc_vhost;
91 /* Pointer to vhost_virtqueue for the cmd */
92 struct vhost_virtqueue *tvc_vq;
93 /* Pointer to vhost nexus memory */
94 struct tcm_vhost_nexus *tvc_nexus;
95 /* The TCM I/O descriptor that is accessed via container_of() */
96 struct se_cmd tvc_se_cmd;
97 /* work item used for cmwq dispatch to tcm_vhost_submission_work() */
98 struct work_struct work;
99 /* Copy of the incoming SCSI command descriptor block (CDB) */
100 unsigned char tvc_cdb[TCM_VHOST_MAX_CDB_SIZE];
101 /* Sense buffer that will be mapped into outgoing status */
102 unsigned char tvc_sense_buf[TRANSPORT_SENSE_BUFFER];
103 /* Completed commands list, serviced from vhost worker thread */
104 struct llist_node tvc_completion_list;
105 /* Used to track inflight cmd */
106 struct vhost_scsi_inflight *inflight;
109 struct tcm_vhost_nexus {
110 /* Pointer to TCM session for I_T Nexus */
111 struct se_session *tvn_se_sess;
114 struct tcm_vhost_nacl {
115 /* Binary World Wide unique Port Name for Vhost Initiator port */
117 /* ASCII formatted WWPN for Sas Initiator port */
118 char iport_name[TCM_VHOST_NAMELEN];
119 /* Returned by tcm_vhost_make_nodeacl() */
120 struct se_node_acl se_node_acl;
123 struct tcm_vhost_tpg {
124 /* Vhost port target portal group tag for TCM */
126 /* Used to track number of TPG Port/Lun Links wrt to explict I_T Nexus shutdown */
127 int tv_tpg_port_count;
128 /* Used for vhost_scsi device reference to tpg_nexus, protected by tv_tpg_mutex */
129 int tv_tpg_vhost_count;
130 /* list for tcm_vhost_list */
131 struct list_head tv_tpg_list;
132 /* Used to protect access for tpg_nexus */
133 struct mutex tv_tpg_mutex;
134 /* Pointer to the TCM VHost I_T Nexus for this TPG endpoint */
135 struct tcm_vhost_nexus *tpg_nexus;
136 /* Pointer back to tcm_vhost_tport */
137 struct tcm_vhost_tport *tport;
138 /* Returned by tcm_vhost_make_tpg() */
139 struct se_portal_group se_tpg;
140 /* Pointer back to vhost_scsi, protected by tv_tpg_mutex */
141 struct vhost_scsi *vhost_scsi;
144 struct tcm_vhost_tport {
145 /* SCSI protocol the tport is providing */
147 /* Binary World Wide unique Port Name for Vhost Target port */
149 /* ASCII formatted WWPN for Vhost Target port */
150 char tport_name[TCM_VHOST_NAMELEN];
151 /* Returned by tcm_vhost_make_tport() */
152 struct se_wwn tport_wwn;
155 struct tcm_vhost_evt {
156 /* event to be sent to guest */
157 struct virtio_scsi_event event;
158 /* event list, serviced from vhost worker thread */
159 struct llist_node list;
163 VHOST_SCSI_VQ_CTL = 0,
164 VHOST_SCSI_VQ_EVT = 1,
165 VHOST_SCSI_VQ_IO = 2,
169 VHOST_SCSI_FEATURES = VHOST_FEATURES | (1ULL << VIRTIO_SCSI_F_HOTPLUG)
172 #define VHOST_SCSI_MAX_TARGET 256
173 #define VHOST_SCSI_MAX_VQ 128
174 #define VHOST_SCSI_MAX_EVENT 128
176 struct vhost_scsi_virtqueue {
177 struct vhost_virtqueue vq;
179 * Reference counting for inflight reqs, used for flush operation. At
180 * each time, one reference tracks new commands submitted, while we
181 * wait for another one to reach 0.
183 struct vhost_scsi_inflight inflights[2];
185 * Indicate current inflight in use, protected by vq->mutex.
186 * Writers must also take dev mutex and flush under it.
192 /* Protected by vhost_scsi->dev.mutex */
193 struct tcm_vhost_tpg **vs_tpg;
194 char vs_vhost_wwpn[TRANSPORT_IQN_LEN];
196 struct vhost_dev dev;
197 struct vhost_scsi_virtqueue vqs[VHOST_SCSI_MAX_VQ];
199 struct vhost_work vs_completion_work; /* cmd completion work item */
200 struct llist_head vs_completion_list; /* cmd completion queue */
202 struct vhost_work vs_event_work; /* evt injection work item */
203 struct llist_head vs_event_list; /* evt injection queue */
205 bool vs_events_missed; /* any missed events, protected by vq->mutex */
206 int vs_events_nr; /* num of pending events, protected by vq->mutex */
209 /* Local pointer to allocated TCM configfs fabric module */
210 static struct target_fabric_configfs *tcm_vhost_fabric_configfs;
212 static struct workqueue_struct *tcm_vhost_workqueue;
214 /* Global spinlock to protect tcm_vhost TPG list for vhost IOCTL access */
215 static DEFINE_MUTEX(tcm_vhost_mutex);
216 static LIST_HEAD(tcm_vhost_list);
218 static int iov_num_pages(struct iovec *iov)
220 return (PAGE_ALIGN((unsigned long)iov->iov_base + iov->iov_len) -
221 ((unsigned long)iov->iov_base & PAGE_MASK)) >> PAGE_SHIFT;
224 static void tcm_vhost_done_inflight(struct kref *kref)
226 struct vhost_scsi_inflight *inflight;
228 inflight = container_of(kref, struct vhost_scsi_inflight, kref);
229 complete(&inflight->comp);
232 static void tcm_vhost_init_inflight(struct vhost_scsi *vs,
233 struct vhost_scsi_inflight *old_inflight[])
235 struct vhost_scsi_inflight *new_inflight;
236 struct vhost_virtqueue *vq;
239 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
242 mutex_lock(&vq->mutex);
244 /* store old infight */
245 idx = vs->vqs[i].inflight_idx;
247 old_inflight[i] = &vs->vqs[i].inflights[idx];
249 /* setup new infight */
250 vs->vqs[i].inflight_idx = idx ^ 1;
251 new_inflight = &vs->vqs[i].inflights[idx ^ 1];
252 kref_init(&new_inflight->kref);
253 init_completion(&new_inflight->comp);
255 mutex_unlock(&vq->mutex);
259 static struct vhost_scsi_inflight *
260 tcm_vhost_get_inflight(struct vhost_virtqueue *vq)
262 struct vhost_scsi_inflight *inflight;
263 struct vhost_scsi_virtqueue *svq;
265 svq = container_of(vq, struct vhost_scsi_virtqueue, vq);
266 inflight = &svq->inflights[svq->inflight_idx];
267 kref_get(&inflight->kref);
272 static void tcm_vhost_put_inflight(struct vhost_scsi_inflight *inflight)
274 kref_put(&inflight->kref, tcm_vhost_done_inflight);
277 static int tcm_vhost_check_true(struct se_portal_group *se_tpg)
282 static int tcm_vhost_check_false(struct se_portal_group *se_tpg)
287 static char *tcm_vhost_get_fabric_name(void)
292 static u8 tcm_vhost_get_fabric_proto_ident(struct se_portal_group *se_tpg)
294 struct tcm_vhost_tpg *tpg = container_of(se_tpg,
295 struct tcm_vhost_tpg, se_tpg);
296 struct tcm_vhost_tport *tport = tpg->tport;
298 switch (tport->tport_proto_id) {
299 case SCSI_PROTOCOL_SAS:
300 return sas_get_fabric_proto_ident(se_tpg);
301 case SCSI_PROTOCOL_FCP:
302 return fc_get_fabric_proto_ident(se_tpg);
303 case SCSI_PROTOCOL_ISCSI:
304 return iscsi_get_fabric_proto_ident(se_tpg);
306 pr_err("Unknown tport_proto_id: 0x%02x, using"
307 " SAS emulation\n", tport->tport_proto_id);
311 return sas_get_fabric_proto_ident(se_tpg);
314 static char *tcm_vhost_get_fabric_wwn(struct se_portal_group *se_tpg)
316 struct tcm_vhost_tpg *tpg = container_of(se_tpg,
317 struct tcm_vhost_tpg, se_tpg);
318 struct tcm_vhost_tport *tport = tpg->tport;
320 return &tport->tport_name[0];
323 static u16 tcm_vhost_get_tag(struct se_portal_group *se_tpg)
325 struct tcm_vhost_tpg *tpg = container_of(se_tpg,
326 struct tcm_vhost_tpg, se_tpg);
327 return tpg->tport_tpgt;
330 static u32 tcm_vhost_get_default_depth(struct se_portal_group *se_tpg)
336 tcm_vhost_get_pr_transport_id(struct se_portal_group *se_tpg,
337 struct se_node_acl *se_nacl,
338 struct t10_pr_registration *pr_reg,
342 struct tcm_vhost_tpg *tpg = container_of(se_tpg,
343 struct tcm_vhost_tpg, se_tpg);
344 struct tcm_vhost_tport *tport = tpg->tport;
346 switch (tport->tport_proto_id) {
347 case SCSI_PROTOCOL_SAS:
348 return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
350 case SCSI_PROTOCOL_FCP:
351 return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
353 case SCSI_PROTOCOL_ISCSI:
354 return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
357 pr_err("Unknown tport_proto_id: 0x%02x, using"
358 " SAS emulation\n", tport->tport_proto_id);
362 return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
367 tcm_vhost_get_pr_transport_id_len(struct se_portal_group *se_tpg,
368 struct se_node_acl *se_nacl,
369 struct t10_pr_registration *pr_reg,
372 struct tcm_vhost_tpg *tpg = container_of(se_tpg,
373 struct tcm_vhost_tpg, se_tpg);
374 struct tcm_vhost_tport *tport = tpg->tport;
376 switch (tport->tport_proto_id) {
377 case SCSI_PROTOCOL_SAS:
378 return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
380 case SCSI_PROTOCOL_FCP:
381 return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
383 case SCSI_PROTOCOL_ISCSI:
384 return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
387 pr_err("Unknown tport_proto_id: 0x%02x, using"
388 " SAS emulation\n", tport->tport_proto_id);
392 return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
397 tcm_vhost_parse_pr_out_transport_id(struct se_portal_group *se_tpg,
400 char **port_nexus_ptr)
402 struct tcm_vhost_tpg *tpg = container_of(se_tpg,
403 struct tcm_vhost_tpg, se_tpg);
404 struct tcm_vhost_tport *tport = tpg->tport;
406 switch (tport->tport_proto_id) {
407 case SCSI_PROTOCOL_SAS:
408 return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
410 case SCSI_PROTOCOL_FCP:
411 return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
413 case SCSI_PROTOCOL_ISCSI:
414 return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
417 pr_err("Unknown tport_proto_id: 0x%02x, using"
418 " SAS emulation\n", tport->tport_proto_id);
422 return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
426 static struct se_node_acl *
427 tcm_vhost_alloc_fabric_acl(struct se_portal_group *se_tpg)
429 struct tcm_vhost_nacl *nacl;
431 nacl = kzalloc(sizeof(struct tcm_vhost_nacl), GFP_KERNEL);
433 pr_err("Unable to allocate struct tcm_vhost_nacl\n");
437 return &nacl->se_node_acl;
441 tcm_vhost_release_fabric_acl(struct se_portal_group *se_tpg,
442 struct se_node_acl *se_nacl)
444 struct tcm_vhost_nacl *nacl = container_of(se_nacl,
445 struct tcm_vhost_nacl, se_node_acl);
449 static u32 tcm_vhost_tpg_get_inst_index(struct se_portal_group *se_tpg)
454 static void tcm_vhost_release_cmd(struct se_cmd *se_cmd)
456 struct tcm_vhost_cmd *tv_cmd = container_of(se_cmd,
457 struct tcm_vhost_cmd, tvc_se_cmd);
458 struct se_session *se_sess = se_cmd->se_sess;
460 if (tv_cmd->tvc_sgl_count) {
462 for (i = 0; i < tv_cmd->tvc_sgl_count; i++)
463 put_page(sg_page(&tv_cmd->tvc_sgl[i]));
466 tcm_vhost_put_inflight(tv_cmd->inflight);
467 percpu_ida_free(&se_sess->sess_tag_pool, se_cmd->map_tag);
470 static int tcm_vhost_shutdown_session(struct se_session *se_sess)
475 static void tcm_vhost_close_session(struct se_session *se_sess)
480 static u32 tcm_vhost_sess_get_index(struct se_session *se_sess)
485 static int tcm_vhost_write_pending(struct se_cmd *se_cmd)
487 /* Go ahead and process the write immediately */
488 target_execute_cmd(se_cmd);
492 static int tcm_vhost_write_pending_status(struct se_cmd *se_cmd)
497 static void tcm_vhost_set_default_node_attrs(struct se_node_acl *nacl)
502 static u32 tcm_vhost_get_task_tag(struct se_cmd *se_cmd)
507 static int tcm_vhost_get_cmd_state(struct se_cmd *se_cmd)
512 static void vhost_scsi_complete_cmd(struct tcm_vhost_cmd *cmd)
514 struct vhost_scsi *vs = cmd->tvc_vhost;
516 llist_add(&cmd->tvc_completion_list, &vs->vs_completion_list);
518 vhost_work_queue(&vs->dev, &vs->vs_completion_work);
521 static int tcm_vhost_queue_data_in(struct se_cmd *se_cmd)
523 struct tcm_vhost_cmd *cmd = container_of(se_cmd,
524 struct tcm_vhost_cmd, tvc_se_cmd);
525 vhost_scsi_complete_cmd(cmd);
529 static int tcm_vhost_queue_status(struct se_cmd *se_cmd)
531 struct tcm_vhost_cmd *cmd = container_of(se_cmd,
532 struct tcm_vhost_cmd, tvc_se_cmd);
533 vhost_scsi_complete_cmd(cmd);
537 static void tcm_vhost_queue_tm_rsp(struct se_cmd *se_cmd)
542 static void tcm_vhost_free_evt(struct vhost_scsi *vs, struct tcm_vhost_evt *evt)
548 static struct tcm_vhost_evt *
549 tcm_vhost_allocate_evt(struct vhost_scsi *vs,
550 u32 event, u32 reason)
552 struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
553 struct tcm_vhost_evt *evt;
555 if (vs->vs_events_nr > VHOST_SCSI_MAX_EVENT) {
556 vs->vs_events_missed = true;
560 evt = kzalloc(sizeof(*evt), GFP_KERNEL);
562 vq_err(vq, "Failed to allocate tcm_vhost_evt\n");
563 vs->vs_events_missed = true;
567 evt->event.event = event;
568 evt->event.reason = reason;
574 static void vhost_scsi_free_cmd(struct tcm_vhost_cmd *cmd)
576 struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
578 /* TODO locking against target/backend threads? */
579 transport_generic_free_cmd(se_cmd, 0);
583 static int vhost_scsi_check_stop_free(struct se_cmd *se_cmd)
585 return target_put_sess_cmd(se_cmd->se_sess, se_cmd);
589 tcm_vhost_do_evt_work(struct vhost_scsi *vs, struct tcm_vhost_evt *evt)
591 struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
592 struct virtio_scsi_event *event = &evt->event;
593 struct virtio_scsi_event __user *eventp;
597 if (!vq->private_data) {
598 vs->vs_events_missed = true;
603 vhost_disable_notify(&vs->dev, vq);
604 head = vhost_get_vq_desc(&vs->dev, vq, vq->iov,
605 ARRAY_SIZE(vq->iov), &out, &in,
608 vs->vs_events_missed = true;
611 if (head == vq->num) {
612 if (vhost_enable_notify(&vs->dev, vq))
614 vs->vs_events_missed = true;
618 if ((vq->iov[out].iov_len != sizeof(struct virtio_scsi_event))) {
619 vq_err(vq, "Expecting virtio_scsi_event, got %zu bytes\n",
620 vq->iov[out].iov_len);
621 vs->vs_events_missed = true;
625 if (vs->vs_events_missed) {
626 event->event |= VIRTIO_SCSI_T_EVENTS_MISSED;
627 vs->vs_events_missed = false;
630 eventp = vq->iov[out].iov_base;
631 ret = __copy_to_user(eventp, event, sizeof(*event));
633 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
635 vq_err(vq, "Faulted on tcm_vhost_send_event\n");
638 static void tcm_vhost_evt_work(struct vhost_work *work)
640 struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
642 struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
643 struct tcm_vhost_evt *evt;
644 struct llist_node *llnode;
646 mutex_lock(&vq->mutex);
647 llnode = llist_del_all(&vs->vs_event_list);
649 evt = llist_entry(llnode, struct tcm_vhost_evt, list);
650 llnode = llist_next(llnode);
651 tcm_vhost_do_evt_work(vs, evt);
652 tcm_vhost_free_evt(vs, evt);
654 mutex_unlock(&vq->mutex);
657 /* Fill in status and signal that we are done processing this command
659 * This is scheduled in the vhost work queue so we are called with the owner
660 * process mm and can access the vring.
662 static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
664 struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
666 DECLARE_BITMAP(signal, VHOST_SCSI_MAX_VQ);
667 struct virtio_scsi_cmd_resp v_rsp;
668 struct tcm_vhost_cmd *cmd;
669 struct llist_node *llnode;
670 struct se_cmd *se_cmd;
673 bitmap_zero(signal, VHOST_SCSI_MAX_VQ);
674 llnode = llist_del_all(&vs->vs_completion_list);
676 cmd = llist_entry(llnode, struct tcm_vhost_cmd,
677 tvc_completion_list);
678 llnode = llist_next(llnode);
679 se_cmd = &cmd->tvc_se_cmd;
681 pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__,
682 cmd, se_cmd->residual_count, se_cmd->scsi_status);
684 memset(&v_rsp, 0, sizeof(v_rsp));
685 v_rsp.resid = se_cmd->residual_count;
686 /* TODO is status_qualifier field needed? */
687 v_rsp.status = se_cmd->scsi_status;
688 v_rsp.sense_len = se_cmd->scsi_sense_length;
689 memcpy(v_rsp.sense, cmd->tvc_sense_buf,
691 ret = copy_to_user(cmd->tvc_resp, &v_rsp, sizeof(v_rsp));
692 if (likely(ret == 0)) {
693 struct vhost_scsi_virtqueue *q;
694 vhost_add_used(cmd->tvc_vq, cmd->tvc_vq_desc, 0);
695 q = container_of(cmd->tvc_vq, struct vhost_scsi_virtqueue, vq);
697 __set_bit(vq, signal);
699 pr_err("Faulted on virtio_scsi_cmd_resp\n");
701 vhost_scsi_free_cmd(cmd);
705 while ((vq = find_next_bit(signal, VHOST_SCSI_MAX_VQ, vq + 1))
707 vhost_signal(&vs->dev, &vs->vqs[vq].vq);
710 static struct tcm_vhost_cmd *
711 vhost_scsi_get_tag(struct vhost_virtqueue *vq,
712 struct tcm_vhost_tpg *tpg,
713 struct virtio_scsi_cmd_req *v_req,
717 struct tcm_vhost_cmd *cmd;
718 struct tcm_vhost_nexus *tv_nexus;
719 struct se_session *se_sess;
720 struct scatterlist *sg;
724 tv_nexus = tpg->tpg_nexus;
726 pr_err("Unable to locate active struct tcm_vhost_nexus\n");
727 return ERR_PTR(-EIO);
729 se_sess = tv_nexus->tvn_se_sess;
731 tag = percpu_ida_alloc(&se_sess->sess_tag_pool, GFP_KERNEL);
732 cmd = &((struct tcm_vhost_cmd *)se_sess->sess_cmd_map)[tag];
734 pages = cmd->tvc_upages;
735 memset(cmd, 0, sizeof(struct tcm_vhost_cmd));
738 cmd->tvc_upages = pages;
739 cmd->tvc_se_cmd.map_tag = tag;
740 cmd->tvc_tag = v_req->tag;
741 cmd->tvc_task_attr = v_req->task_attr;
742 cmd->tvc_exp_data_len = exp_data_len;
743 cmd->tvc_data_direction = data_direction;
744 cmd->tvc_nexus = tv_nexus;
745 cmd->inflight = tcm_vhost_get_inflight(vq);
751 * Map a user memory range into a scatterlist
753 * Returns the number of scatterlist entries used or -errno on error.
756 vhost_scsi_map_to_sgl(struct tcm_vhost_cmd *tv_cmd,
757 struct scatterlist *sgl,
758 unsigned int sgl_count,
762 unsigned int npages = 0, pages_nr, offset, nbytes;
763 struct scatterlist *sg = sgl;
764 void __user *ptr = iov->iov_base;
765 size_t len = iov->iov_len;
769 if (sgl_count > TCM_VHOST_PREALLOC_SGLS) {
770 pr_err("vhost_scsi_map_to_sgl() psgl_count: %u greater than"
771 " preallocated TCM_VHOST_PREALLOC_SGLS: %u\n",
772 sgl_count, TCM_VHOST_PREALLOC_SGLS);
776 pages_nr = iov_num_pages(iov);
777 if (pages_nr > sgl_count)
780 if (pages_nr > TCM_VHOST_PREALLOC_PAGES) {
781 pr_err("vhost_scsi_map_to_sgl() pages_nr: %u greater than"
782 " preallocated TCM_VHOST_PREALLOC_PAGES: %u\n",
783 pages_nr, TCM_VHOST_PREALLOC_PAGES);
787 pages = tv_cmd->tvc_upages;
789 ret = get_user_pages_fast((unsigned long)ptr, pages_nr, write, pages);
790 /* No pages were pinned */
793 /* Less pages pinned than wanted */
794 if (ret != pages_nr) {
795 for (i = 0; i < ret; i++)
802 offset = (uintptr_t)ptr & ~PAGE_MASK;
803 nbytes = min_t(unsigned int, PAGE_SIZE - offset, len);
804 sg_set_page(sg, pages[npages], nbytes, offset);
816 vhost_scsi_map_iov_to_sgl(struct tcm_vhost_cmd *cmd,
824 struct scatterlist *sg;
827 * Find out how long sglist needs to be
830 for (i = 0; i < niov; i++)
831 sgl_count += iov_num_pages(&iov[i]);
833 /* TODO overflow checking */
836 pr_debug("%s sg %p sgl_count %u\n", __func__, sg, sgl_count);
837 sg_init_table(sg, sgl_count);
839 cmd->tvc_sgl_count = sgl_count;
841 pr_debug("Mapping %u iovecs for %u pages\n", niov, sgl_count);
842 for (i = 0; i < niov; i++) {
843 ret = vhost_scsi_map_to_sgl(cmd, sg, sgl_count, &iov[i],
846 for (i = 0; i < cmd->tvc_sgl_count; i++)
847 put_page(sg_page(&cmd->tvc_sgl[i]));
849 cmd->tvc_sgl_count = 0;
859 static void tcm_vhost_submission_work(struct work_struct *work)
861 struct tcm_vhost_cmd *cmd =
862 container_of(work, struct tcm_vhost_cmd, work);
863 struct tcm_vhost_nexus *tv_nexus;
864 struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
865 struct scatterlist *sg_ptr, *sg_bidi_ptr = NULL;
866 int rc, sg_no_bidi = 0;
868 if (cmd->tvc_sgl_count) {
869 sg_ptr = cmd->tvc_sgl;
870 /* FIXME: Fix BIDI operation in tcm_vhost_submission_work() */
872 if (se_cmd->se_cmd_flags & SCF_BIDI) {
880 tv_nexus = cmd->tvc_nexus;
882 rc = target_submit_cmd_map_sgls(se_cmd, tv_nexus->tvn_se_sess,
883 cmd->tvc_cdb, &cmd->tvc_sense_buf[0],
884 cmd->tvc_lun, cmd->tvc_exp_data_len,
885 cmd->tvc_task_attr, cmd->tvc_data_direction,
886 TARGET_SCF_ACK_KREF, sg_ptr, cmd->tvc_sgl_count,
887 sg_bidi_ptr, sg_no_bidi);
889 transport_send_check_condition_and_sense(se_cmd,
890 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
891 transport_generic_free_cmd(se_cmd, 0);
896 vhost_scsi_send_bad_target(struct vhost_scsi *vs,
897 struct vhost_virtqueue *vq,
898 int head, unsigned out)
900 struct virtio_scsi_cmd_resp __user *resp;
901 struct virtio_scsi_cmd_resp rsp;
904 memset(&rsp, 0, sizeof(rsp));
905 rsp.response = VIRTIO_SCSI_S_BAD_TARGET;
906 resp = vq->iov[out].iov_base;
907 ret = __copy_to_user(resp, &rsp, sizeof(rsp));
909 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
911 pr_err("Faulted on virtio_scsi_cmd_resp\n");
915 vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
917 struct tcm_vhost_tpg **vs_tpg;
918 struct virtio_scsi_cmd_req v_req;
919 struct tcm_vhost_tpg *tpg;
920 struct tcm_vhost_cmd *cmd;
921 u32 exp_data_len, data_first, data_num, data_direction;
926 mutex_lock(&vq->mutex);
928 * We can handle the vq only after the endpoint is setup by calling the
929 * VHOST_SCSI_SET_ENDPOINT ioctl.
931 vs_tpg = vq->private_data;
935 vhost_disable_notify(&vs->dev, vq);
938 head = vhost_get_vq_desc(&vs->dev, vq, vq->iov,
939 ARRAY_SIZE(vq->iov), &out, &in,
941 pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n",
943 /* On error, stop handling until the next kick. */
944 if (unlikely(head < 0))
946 /* Nothing new? Wait for eventfd to tell us they refilled. */
947 if (head == vq->num) {
948 if (unlikely(vhost_enable_notify(&vs->dev, vq))) {
949 vhost_disable_notify(&vs->dev, vq);
955 /* FIXME: BIDI operation */
956 if (out == 1 && in == 1) {
957 data_direction = DMA_NONE;
960 } else if (out == 1 && in > 1) {
961 data_direction = DMA_FROM_DEVICE;
962 data_first = out + 1;
964 } else if (out > 1 && in == 1) {
965 data_direction = DMA_TO_DEVICE;
969 vq_err(vq, "Invalid buffer layout out: %u in: %u\n",
975 * Check for a sane resp buffer so we can report errors to
978 if (unlikely(vq->iov[out].iov_len !=
979 sizeof(struct virtio_scsi_cmd_resp))) {
980 vq_err(vq, "Expecting virtio_scsi_cmd_resp, got %zu"
981 " bytes\n", vq->iov[out].iov_len);
985 if (unlikely(vq->iov[0].iov_len != sizeof(v_req))) {
986 vq_err(vq, "Expecting virtio_scsi_cmd_req, got %zu"
987 " bytes\n", vq->iov[0].iov_len);
990 pr_debug("Calling __copy_from_user: vq->iov[0].iov_base: %p,"
991 " len: %zu\n", vq->iov[0].iov_base, sizeof(v_req));
992 ret = __copy_from_user(&v_req, vq->iov[0].iov_base,
995 vq_err(vq, "Faulted on virtio_scsi_cmd_req\n");
999 /* Extract the tpgt */
1000 target = v_req.lun[1];
1001 tpg = ACCESS_ONCE(vs_tpg[target]);
1003 /* Target does not exist, fail the request */
1004 if (unlikely(!tpg)) {
1005 vhost_scsi_send_bad_target(vs, vq, head, out);
1010 for (i = 0; i < data_num; i++)
1011 exp_data_len += vq->iov[data_first + i].iov_len;
1013 cmd = vhost_scsi_get_tag(vq, tpg, &v_req,
1014 exp_data_len, data_direction);
1016 vq_err(vq, "vhost_scsi_get_tag failed %ld\n",
1020 pr_debug("Allocated tv_cmd: %p exp_data_len: %d, data_direction"
1021 ": %d\n", cmd, exp_data_len, data_direction);
1023 cmd->tvc_vhost = vs;
1025 cmd->tvc_resp = vq->iov[out].iov_base;
1028 * Copy in the recieved CDB descriptor into cmd->tvc_cdb
1029 * that will be used by tcm_vhost_new_cmd_map() and down into
1030 * target_setup_cmd_from_cdb()
1032 memcpy(cmd->tvc_cdb, v_req.cdb, TCM_VHOST_MAX_CDB_SIZE);
1034 * Check that the recieved CDB size does not exceeded our
1035 * hardcoded max for tcm_vhost
1037 /* TODO what if cdb was too small for varlen cdb header? */
1038 if (unlikely(scsi_command_size(cmd->tvc_cdb) >
1039 TCM_VHOST_MAX_CDB_SIZE)) {
1040 vq_err(vq, "Received SCSI CDB with command_size: %d that"
1041 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1042 scsi_command_size(cmd->tvc_cdb),
1043 TCM_VHOST_MAX_CDB_SIZE);
1046 cmd->tvc_lun = ((v_req.lun[2] << 8) | v_req.lun[3]) & 0x3FFF;
1048 pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n",
1049 cmd->tvc_cdb[0], cmd->tvc_lun);
1051 if (data_direction != DMA_NONE) {
1052 ret = vhost_scsi_map_iov_to_sgl(cmd,
1053 &vq->iov[data_first], data_num,
1054 data_direction == DMA_TO_DEVICE);
1055 if (unlikely(ret)) {
1056 vq_err(vq, "Failed to map iov to sgl\n");
1062 * Save the descriptor from vhost_get_vq_desc() to be used to
1063 * complete the virtio-scsi request in TCM callback context via
1064 * tcm_vhost_queue_data_in() and tcm_vhost_queue_status()
1066 cmd->tvc_vq_desc = head;
1068 * Dispatch tv_cmd descriptor for cmwq execution in process
1069 * context provided by tcm_vhost_workqueue. This also ensures
1070 * tv_cmd is executed on the same kworker CPU as this vhost
1071 * thread to gain positive L2 cache locality effects..
1073 INIT_WORK(&cmd->work, tcm_vhost_submission_work);
1074 queue_work(tcm_vhost_workqueue, &cmd->work);
1077 mutex_unlock(&vq->mutex);
1081 vhost_scsi_free_cmd(cmd);
1083 vhost_scsi_send_bad_target(vs, vq, head, out);
1085 mutex_unlock(&vq->mutex);
1088 static void vhost_scsi_ctl_handle_kick(struct vhost_work *work)
1090 pr_debug("%s: The handling func for control queue.\n", __func__);
1094 tcm_vhost_send_evt(struct vhost_scsi *vs,
1095 struct tcm_vhost_tpg *tpg,
1100 struct tcm_vhost_evt *evt;
1102 evt = tcm_vhost_allocate_evt(vs, event, reason);
1107 /* TODO: share lun setup code with virtio-scsi.ko */
1109 * Note: evt->event is zeroed when we allocate it and
1110 * lun[4-7] need to be zero according to virtio-scsi spec.
1112 evt->event.lun[0] = 0x01;
1113 evt->event.lun[1] = tpg->tport_tpgt & 0xFF;
1114 if (lun->unpacked_lun >= 256)
1115 evt->event.lun[2] = lun->unpacked_lun >> 8 | 0x40 ;
1116 evt->event.lun[3] = lun->unpacked_lun & 0xFF;
1119 llist_add(&evt->list, &vs->vs_event_list);
1120 vhost_work_queue(&vs->dev, &vs->vs_event_work);
1123 static void vhost_scsi_evt_handle_kick(struct vhost_work *work)
1125 struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1127 struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1129 mutex_lock(&vq->mutex);
1130 if (!vq->private_data)
1133 if (vs->vs_events_missed)
1134 tcm_vhost_send_evt(vs, NULL, NULL, VIRTIO_SCSI_T_NO_EVENT, 0);
1136 mutex_unlock(&vq->mutex);
1139 static void vhost_scsi_handle_kick(struct vhost_work *work)
1141 struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1143 struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1145 vhost_scsi_handle_vq(vs, vq);
1148 static void vhost_scsi_flush_vq(struct vhost_scsi *vs, int index)
1150 vhost_poll_flush(&vs->vqs[index].vq.poll);
1153 /* Callers must hold dev mutex */
1154 static void vhost_scsi_flush(struct vhost_scsi *vs)
1156 struct vhost_scsi_inflight *old_inflight[VHOST_SCSI_MAX_VQ];
1159 /* Init new inflight and remember the old inflight */
1160 tcm_vhost_init_inflight(vs, old_inflight);
1163 * The inflight->kref was initialized to 1. We decrement it here to
1164 * indicate the start of the flush operation so that it will reach 0
1165 * when all the reqs are finished.
1167 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1168 kref_put(&old_inflight[i]->kref, tcm_vhost_done_inflight);
1170 /* Flush both the vhost poll and vhost work */
1171 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1172 vhost_scsi_flush_vq(vs, i);
1173 vhost_work_flush(&vs->dev, &vs->vs_completion_work);
1174 vhost_work_flush(&vs->dev, &vs->vs_event_work);
1176 /* Wait for all reqs issued before the flush to be finished */
1177 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1178 wait_for_completion(&old_inflight[i]->comp);
1182 * Called from vhost_scsi_ioctl() context to walk the list of available
1183 * tcm_vhost_tpg with an active struct tcm_vhost_nexus
1185 * The lock nesting rule is:
1186 * tcm_vhost_mutex -> vs->dev.mutex -> tpg->tv_tpg_mutex -> vq->mutex
1189 vhost_scsi_set_endpoint(struct vhost_scsi *vs,
1190 struct vhost_scsi_target *t)
1192 struct tcm_vhost_tport *tv_tport;
1193 struct tcm_vhost_tpg *tpg;
1194 struct tcm_vhost_tpg **vs_tpg;
1195 struct vhost_virtqueue *vq;
1196 int index, ret, i, len;
1199 mutex_lock(&tcm_vhost_mutex);
1200 mutex_lock(&vs->dev.mutex);
1202 /* Verify that ring has been setup correctly. */
1203 for (index = 0; index < vs->dev.nvqs; ++index) {
1204 /* Verify that ring has been setup correctly. */
1205 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1211 len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET;
1212 vs_tpg = kzalloc(len, GFP_KERNEL);
1218 memcpy(vs_tpg, vs->vs_tpg, len);
1220 list_for_each_entry(tpg, &tcm_vhost_list, tv_tpg_list) {
1221 mutex_lock(&tpg->tv_tpg_mutex);
1222 if (!tpg->tpg_nexus) {
1223 mutex_unlock(&tpg->tv_tpg_mutex);
1226 if (tpg->tv_tpg_vhost_count != 0) {
1227 mutex_unlock(&tpg->tv_tpg_mutex);
1230 tv_tport = tpg->tport;
1232 if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1233 if (vs->vs_tpg && vs->vs_tpg[tpg->tport_tpgt]) {
1235 mutex_unlock(&tpg->tv_tpg_mutex);
1239 tpg->tv_tpg_vhost_count++;
1240 tpg->vhost_scsi = vs;
1241 vs_tpg[tpg->tport_tpgt] = tpg;
1242 smp_mb__after_atomic_inc();
1245 mutex_unlock(&tpg->tv_tpg_mutex);
1249 memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
1250 sizeof(vs->vs_vhost_wwpn));
1251 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1252 vq = &vs->vqs[i].vq;
1253 mutex_lock(&vq->mutex);
1254 vq->private_data = vs_tpg;
1255 vhost_init_used(vq);
1256 mutex_unlock(&vq->mutex);
1264 * Act as synchronize_rcu to make sure access to
1265 * old vs->vs_tpg is finished.
1267 vhost_scsi_flush(vs);
1269 vs->vs_tpg = vs_tpg;
1272 mutex_unlock(&vs->dev.mutex);
1273 mutex_unlock(&tcm_vhost_mutex);
1278 vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
1279 struct vhost_scsi_target *t)
1281 struct tcm_vhost_tport *tv_tport;
1282 struct tcm_vhost_tpg *tpg;
1283 struct vhost_virtqueue *vq;
1288 mutex_lock(&tcm_vhost_mutex);
1289 mutex_lock(&vs->dev.mutex);
1290 /* Verify that ring has been setup correctly. */
1291 for (index = 0; index < vs->dev.nvqs; ++index) {
1292 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1303 for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1305 tpg = vs->vs_tpg[target];
1309 mutex_lock(&tpg->tv_tpg_mutex);
1310 tv_tport = tpg->tport;
1316 if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1317 pr_warn("tv_tport->tport_name: %s, tpg->tport_tpgt: %hu"
1318 " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
1319 tv_tport->tport_name, tpg->tport_tpgt,
1320 t->vhost_wwpn, t->vhost_tpgt);
1324 tpg->tv_tpg_vhost_count--;
1325 tpg->vhost_scsi = NULL;
1326 vs->vs_tpg[target] = NULL;
1328 mutex_unlock(&tpg->tv_tpg_mutex);
1331 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1332 vq = &vs->vqs[i].vq;
1333 mutex_lock(&vq->mutex);
1334 vq->private_data = NULL;
1335 mutex_unlock(&vq->mutex);
1339 * Act as synchronize_rcu to make sure access to
1340 * old vs->vs_tpg is finished.
1342 vhost_scsi_flush(vs);
1345 WARN_ON(vs->vs_events_nr);
1346 mutex_unlock(&vs->dev.mutex);
1347 mutex_unlock(&tcm_vhost_mutex);
1351 mutex_unlock(&tpg->tv_tpg_mutex);
1353 mutex_unlock(&vs->dev.mutex);
1354 mutex_unlock(&tcm_vhost_mutex);
1358 static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features)
1360 if (features & ~VHOST_SCSI_FEATURES)
1363 mutex_lock(&vs->dev.mutex);
1364 if ((features & (1 << VHOST_F_LOG_ALL)) &&
1365 !vhost_log_access_ok(&vs->dev)) {
1366 mutex_unlock(&vs->dev.mutex);
1369 vs->dev.acked_features = features;
1371 vhost_scsi_flush(vs);
1372 mutex_unlock(&vs->dev.mutex);
1376 static int vhost_scsi_open(struct inode *inode, struct file *f)
1378 struct vhost_scsi *vs;
1379 struct vhost_virtqueue **vqs;
1382 vs = kzalloc(sizeof(*vs), GFP_KERNEL);
1386 vqs = kmalloc(VHOST_SCSI_MAX_VQ * sizeof(*vqs), GFP_KERNEL);
1392 vhost_work_init(&vs->vs_completion_work, vhost_scsi_complete_cmd_work);
1393 vhost_work_init(&vs->vs_event_work, tcm_vhost_evt_work);
1395 vs->vs_events_nr = 0;
1396 vs->vs_events_missed = false;
1398 vqs[VHOST_SCSI_VQ_CTL] = &vs->vqs[VHOST_SCSI_VQ_CTL].vq;
1399 vqs[VHOST_SCSI_VQ_EVT] = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1400 vs->vqs[VHOST_SCSI_VQ_CTL].vq.handle_kick = vhost_scsi_ctl_handle_kick;
1401 vs->vqs[VHOST_SCSI_VQ_EVT].vq.handle_kick = vhost_scsi_evt_handle_kick;
1402 for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++) {
1403 vqs[i] = &vs->vqs[i].vq;
1404 vs->vqs[i].vq.handle_kick = vhost_scsi_handle_kick;
1406 r = vhost_dev_init(&vs->dev, vqs, VHOST_SCSI_MAX_VQ);
1408 tcm_vhost_init_inflight(vs, NULL);
1416 f->private_data = vs;
1420 static int vhost_scsi_release(struct inode *inode, struct file *f)
1422 struct vhost_scsi *vs = f->private_data;
1423 struct vhost_scsi_target t;
1425 mutex_lock(&vs->dev.mutex);
1426 memcpy(t.vhost_wwpn, vs->vs_vhost_wwpn, sizeof(t.vhost_wwpn));
1427 mutex_unlock(&vs->dev.mutex);
1428 vhost_scsi_clear_endpoint(vs, &t);
1429 vhost_dev_stop(&vs->dev);
1430 vhost_dev_cleanup(&vs->dev, false);
1431 /* Jobs can re-queue themselves in evt kick handler. Do extra flush. */
1432 vhost_scsi_flush(vs);
1439 vhost_scsi_ioctl(struct file *f,
1443 struct vhost_scsi *vs = f->private_data;
1444 struct vhost_scsi_target backend;
1445 void __user *argp = (void __user *)arg;
1446 u64 __user *featurep = argp;
1447 u32 __user *eventsp = argp;
1450 int r, abi_version = VHOST_SCSI_ABI_VERSION;
1451 struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1454 case VHOST_SCSI_SET_ENDPOINT:
1455 if (copy_from_user(&backend, argp, sizeof backend))
1457 if (backend.reserved != 0)
1460 return vhost_scsi_set_endpoint(vs, &backend);
1461 case VHOST_SCSI_CLEAR_ENDPOINT:
1462 if (copy_from_user(&backend, argp, sizeof backend))
1464 if (backend.reserved != 0)
1467 return vhost_scsi_clear_endpoint(vs, &backend);
1468 case VHOST_SCSI_GET_ABI_VERSION:
1469 if (copy_to_user(argp, &abi_version, sizeof abi_version))
1472 case VHOST_SCSI_SET_EVENTS_MISSED:
1473 if (get_user(events_missed, eventsp))
1475 mutex_lock(&vq->mutex);
1476 vs->vs_events_missed = events_missed;
1477 mutex_unlock(&vq->mutex);
1479 case VHOST_SCSI_GET_EVENTS_MISSED:
1480 mutex_lock(&vq->mutex);
1481 events_missed = vs->vs_events_missed;
1482 mutex_unlock(&vq->mutex);
1483 if (put_user(events_missed, eventsp))
1486 case VHOST_GET_FEATURES:
1487 features = VHOST_SCSI_FEATURES;
1488 if (copy_to_user(featurep, &features, sizeof features))
1491 case VHOST_SET_FEATURES:
1492 if (copy_from_user(&features, featurep, sizeof features))
1494 return vhost_scsi_set_features(vs, features);
1496 mutex_lock(&vs->dev.mutex);
1497 r = vhost_dev_ioctl(&vs->dev, ioctl, argp);
1498 /* TODO: flush backend after dev ioctl. */
1499 if (r == -ENOIOCTLCMD)
1500 r = vhost_vring_ioctl(&vs->dev, ioctl, argp);
1501 mutex_unlock(&vs->dev.mutex);
1506 #ifdef CONFIG_COMPAT
1507 static long vhost_scsi_compat_ioctl(struct file *f, unsigned int ioctl,
1510 return vhost_scsi_ioctl(f, ioctl, (unsigned long)compat_ptr(arg));
1514 static const struct file_operations vhost_scsi_fops = {
1515 .owner = THIS_MODULE,
1516 .release = vhost_scsi_release,
1517 .unlocked_ioctl = vhost_scsi_ioctl,
1518 #ifdef CONFIG_COMPAT
1519 .compat_ioctl = vhost_scsi_compat_ioctl,
1521 .open = vhost_scsi_open,
1522 .llseek = noop_llseek,
1525 static struct miscdevice vhost_scsi_misc = {
1531 static int __init vhost_scsi_register(void)
1533 return misc_register(&vhost_scsi_misc);
1536 static int vhost_scsi_deregister(void)
1538 return misc_deregister(&vhost_scsi_misc);
1541 static char *tcm_vhost_dump_proto_id(struct tcm_vhost_tport *tport)
1543 switch (tport->tport_proto_id) {
1544 case SCSI_PROTOCOL_SAS:
1546 case SCSI_PROTOCOL_FCP:
1548 case SCSI_PROTOCOL_ISCSI:
1558 tcm_vhost_do_plug(struct tcm_vhost_tpg *tpg,
1559 struct se_lun *lun, bool plug)
1562 struct vhost_scsi *vs = tpg->vhost_scsi;
1563 struct vhost_virtqueue *vq;
1569 mutex_lock(&vs->dev.mutex);
1570 if (!vhost_has_feature(&vs->dev, VIRTIO_SCSI_F_HOTPLUG)) {
1571 mutex_unlock(&vs->dev.mutex);
1576 reason = VIRTIO_SCSI_EVT_RESET_RESCAN;
1578 reason = VIRTIO_SCSI_EVT_RESET_REMOVED;
1580 vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1581 mutex_lock(&vq->mutex);
1582 tcm_vhost_send_evt(vs, tpg, lun,
1583 VIRTIO_SCSI_T_TRANSPORT_RESET, reason);
1584 mutex_unlock(&vq->mutex);
1585 mutex_unlock(&vs->dev.mutex);
1588 static void tcm_vhost_hotplug(struct tcm_vhost_tpg *tpg, struct se_lun *lun)
1590 tcm_vhost_do_plug(tpg, lun, true);
1593 static void tcm_vhost_hotunplug(struct tcm_vhost_tpg *tpg, struct se_lun *lun)
1595 tcm_vhost_do_plug(tpg, lun, false);
1598 static int tcm_vhost_port_link(struct se_portal_group *se_tpg,
1601 struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1602 struct tcm_vhost_tpg, se_tpg);
1604 mutex_lock(&tcm_vhost_mutex);
1606 mutex_lock(&tpg->tv_tpg_mutex);
1607 tpg->tv_tpg_port_count++;
1608 mutex_unlock(&tpg->tv_tpg_mutex);
1610 tcm_vhost_hotplug(tpg, lun);
1612 mutex_unlock(&tcm_vhost_mutex);
1617 static void tcm_vhost_port_unlink(struct se_portal_group *se_tpg,
1620 struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1621 struct tcm_vhost_tpg, se_tpg);
1623 mutex_lock(&tcm_vhost_mutex);
1625 mutex_lock(&tpg->tv_tpg_mutex);
1626 tpg->tv_tpg_port_count--;
1627 mutex_unlock(&tpg->tv_tpg_mutex);
1629 tcm_vhost_hotunplug(tpg, lun);
1631 mutex_unlock(&tcm_vhost_mutex);
1634 static struct se_node_acl *
1635 tcm_vhost_make_nodeacl(struct se_portal_group *se_tpg,
1636 struct config_group *group,
1639 struct se_node_acl *se_nacl, *se_nacl_new;
1640 struct tcm_vhost_nacl *nacl;
1644 /* tcm_vhost_parse_wwn(name, &wwpn, 1) < 0)
1645 return ERR_PTR(-EINVAL); */
1646 se_nacl_new = tcm_vhost_alloc_fabric_acl(se_tpg);
1648 return ERR_PTR(-ENOMEM);
1652 * se_nacl_new may be released by core_tpg_add_initiator_node_acl()
1653 * when converting a NodeACL from demo mode -> explict
1655 se_nacl = core_tpg_add_initiator_node_acl(se_tpg, se_nacl_new,
1657 if (IS_ERR(se_nacl)) {
1658 tcm_vhost_release_fabric_acl(se_tpg, se_nacl_new);
1662 * Locate our struct tcm_vhost_nacl and set the FC Nport WWPN
1664 nacl = container_of(se_nacl, struct tcm_vhost_nacl, se_node_acl);
1665 nacl->iport_wwpn = wwpn;
1670 static void tcm_vhost_drop_nodeacl(struct se_node_acl *se_acl)
1672 struct tcm_vhost_nacl *nacl = container_of(se_acl,
1673 struct tcm_vhost_nacl, se_node_acl);
1674 core_tpg_del_initiator_node_acl(se_acl->se_tpg, se_acl, 1);
1678 static void tcm_vhost_free_cmd_map_res(struct tcm_vhost_nexus *nexus,
1679 struct se_session *se_sess)
1681 struct tcm_vhost_cmd *tv_cmd;
1684 if (!se_sess->sess_cmd_map)
1687 for (i = 0; i < TCM_VHOST_DEFAULT_TAGS; i++) {
1688 tv_cmd = &((struct tcm_vhost_cmd *)se_sess->sess_cmd_map)[i];
1690 kfree(tv_cmd->tvc_sgl);
1691 kfree(tv_cmd->tvc_upages);
1695 static int tcm_vhost_make_nexus(struct tcm_vhost_tpg *tpg,
1698 struct se_portal_group *se_tpg;
1699 struct se_session *se_sess;
1700 struct tcm_vhost_nexus *tv_nexus;
1701 struct tcm_vhost_cmd *tv_cmd;
1704 mutex_lock(&tpg->tv_tpg_mutex);
1705 if (tpg->tpg_nexus) {
1706 mutex_unlock(&tpg->tv_tpg_mutex);
1707 pr_debug("tpg->tpg_nexus already exists\n");
1710 se_tpg = &tpg->se_tpg;
1712 tv_nexus = kzalloc(sizeof(struct tcm_vhost_nexus), GFP_KERNEL);
1714 mutex_unlock(&tpg->tv_tpg_mutex);
1715 pr_err("Unable to allocate struct tcm_vhost_nexus\n");
1719 * Initialize the struct se_session pointer and setup tagpool
1720 * for struct tcm_vhost_cmd descriptors
1722 tv_nexus->tvn_se_sess = transport_init_session_tags(
1723 TCM_VHOST_DEFAULT_TAGS,
1724 sizeof(struct tcm_vhost_cmd));
1725 if (IS_ERR(tv_nexus->tvn_se_sess)) {
1726 mutex_unlock(&tpg->tv_tpg_mutex);
1730 se_sess = tv_nexus->tvn_se_sess;
1731 for (i = 0; i < TCM_VHOST_DEFAULT_TAGS; i++) {
1732 tv_cmd = &((struct tcm_vhost_cmd *)se_sess->sess_cmd_map)[i];
1734 tv_cmd->tvc_sgl = kzalloc(sizeof(struct scatterlist) *
1735 TCM_VHOST_PREALLOC_SGLS, GFP_KERNEL);
1736 if (!tv_cmd->tvc_sgl) {
1737 mutex_unlock(&tpg->tv_tpg_mutex);
1738 pr_err("Unable to allocate tv_cmd->tvc_sgl\n");
1742 tv_cmd->tvc_upages = kzalloc(sizeof(struct page *) *
1743 TCM_VHOST_PREALLOC_PAGES, GFP_KERNEL);
1744 if (!tv_cmd->tvc_upages) {
1745 mutex_unlock(&tpg->tv_tpg_mutex);
1746 pr_err("Unable to allocate tv_cmd->tvc_upages\n");
1751 * Since we are running in 'demo mode' this call with generate a
1752 * struct se_node_acl for the tcm_vhost struct se_portal_group with
1753 * the SCSI Initiator port name of the passed configfs group 'name'.
1755 tv_nexus->tvn_se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
1756 se_tpg, (unsigned char *)name);
1757 if (!tv_nexus->tvn_se_sess->se_node_acl) {
1758 mutex_unlock(&tpg->tv_tpg_mutex);
1759 pr_debug("core_tpg_check_initiator_node_acl() failed"
1764 * Now register the TCM vhost virtual I_T Nexus as active with the
1765 * call to __transport_register_session()
1767 __transport_register_session(se_tpg, tv_nexus->tvn_se_sess->se_node_acl,
1768 tv_nexus->tvn_se_sess, tv_nexus);
1769 tpg->tpg_nexus = tv_nexus;
1771 mutex_unlock(&tpg->tv_tpg_mutex);
1775 tcm_vhost_free_cmd_map_res(tv_nexus, se_sess);
1776 transport_free_session(se_sess);
1781 static int tcm_vhost_drop_nexus(struct tcm_vhost_tpg *tpg)
1783 struct se_session *se_sess;
1784 struct tcm_vhost_nexus *tv_nexus;
1786 mutex_lock(&tpg->tv_tpg_mutex);
1787 tv_nexus = tpg->tpg_nexus;
1789 mutex_unlock(&tpg->tv_tpg_mutex);
1793 se_sess = tv_nexus->tvn_se_sess;
1795 mutex_unlock(&tpg->tv_tpg_mutex);
1799 if (tpg->tv_tpg_port_count != 0) {
1800 mutex_unlock(&tpg->tv_tpg_mutex);
1801 pr_err("Unable to remove TCM_vhost I_T Nexus with"
1802 " active TPG port count: %d\n",
1803 tpg->tv_tpg_port_count);
1807 if (tpg->tv_tpg_vhost_count != 0) {
1808 mutex_unlock(&tpg->tv_tpg_mutex);
1809 pr_err("Unable to remove TCM_vhost I_T Nexus with"
1810 " active TPG vhost count: %d\n",
1811 tpg->tv_tpg_vhost_count);
1815 pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated"
1816 " %s Initiator Port: %s\n", tcm_vhost_dump_proto_id(tpg->tport),
1817 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1819 tcm_vhost_free_cmd_map_res(tv_nexus, se_sess);
1821 * Release the SCSI I_T Nexus to the emulated vhost Target Port
1823 transport_deregister_session(tv_nexus->tvn_se_sess);
1824 tpg->tpg_nexus = NULL;
1825 mutex_unlock(&tpg->tv_tpg_mutex);
1831 static ssize_t tcm_vhost_tpg_show_nexus(struct se_portal_group *se_tpg,
1834 struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1835 struct tcm_vhost_tpg, se_tpg);
1836 struct tcm_vhost_nexus *tv_nexus;
1839 mutex_lock(&tpg->tv_tpg_mutex);
1840 tv_nexus = tpg->tpg_nexus;
1842 mutex_unlock(&tpg->tv_tpg_mutex);
1845 ret = snprintf(page, PAGE_SIZE, "%s\n",
1846 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1847 mutex_unlock(&tpg->tv_tpg_mutex);
1852 static ssize_t tcm_vhost_tpg_store_nexus(struct se_portal_group *se_tpg,
1856 struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1857 struct tcm_vhost_tpg, se_tpg);
1858 struct tcm_vhost_tport *tport_wwn = tpg->tport;
1859 unsigned char i_port[TCM_VHOST_NAMELEN], *ptr, *port_ptr;
1862 * Shutdown the active I_T nexus if 'NULL' is passed..
1864 if (!strncmp(page, "NULL", 4)) {
1865 ret = tcm_vhost_drop_nexus(tpg);
1866 return (!ret) ? count : ret;
1869 * Otherwise make sure the passed virtual Initiator port WWN matches
1870 * the fabric protocol_id set in tcm_vhost_make_tport(), and call
1871 * tcm_vhost_make_nexus().
1873 if (strlen(page) >= TCM_VHOST_NAMELEN) {
1874 pr_err("Emulated NAA Sas Address: %s, exceeds"
1875 " max: %d\n", page, TCM_VHOST_NAMELEN);
1878 snprintf(&i_port[0], TCM_VHOST_NAMELEN, "%s", page);
1880 ptr = strstr(i_port, "naa.");
1882 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
1883 pr_err("Passed SAS Initiator Port %s does not"
1884 " match target port protoid: %s\n", i_port,
1885 tcm_vhost_dump_proto_id(tport_wwn));
1888 port_ptr = &i_port[0];
1891 ptr = strstr(i_port, "fc.");
1893 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
1894 pr_err("Passed FCP Initiator Port %s does not"
1895 " match target port protoid: %s\n", i_port,
1896 tcm_vhost_dump_proto_id(tport_wwn));
1899 port_ptr = &i_port[3]; /* Skip over "fc." */
1902 ptr = strstr(i_port, "iqn.");
1904 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
1905 pr_err("Passed iSCSI Initiator Port %s does not"
1906 " match target port protoid: %s\n", i_port,
1907 tcm_vhost_dump_proto_id(tport_wwn));
1910 port_ptr = &i_port[0];
1913 pr_err("Unable to locate prefix for emulated Initiator Port:"
1917 * Clear any trailing newline for the NAA WWN
1920 if (i_port[strlen(i_port)-1] == '\n')
1921 i_port[strlen(i_port)-1] = '\0';
1923 ret = tcm_vhost_make_nexus(tpg, port_ptr);
1930 TF_TPG_BASE_ATTR(tcm_vhost, nexus, S_IRUGO | S_IWUSR);
1932 static struct configfs_attribute *tcm_vhost_tpg_attrs[] = {
1933 &tcm_vhost_tpg_nexus.attr,
1937 static struct se_portal_group *
1938 tcm_vhost_make_tpg(struct se_wwn *wwn,
1939 struct config_group *group,
1942 struct tcm_vhost_tport *tport = container_of(wwn,
1943 struct tcm_vhost_tport, tport_wwn);
1945 struct tcm_vhost_tpg *tpg;
1949 if (strstr(name, "tpgt_") != name)
1950 return ERR_PTR(-EINVAL);
1951 if (kstrtoul(name + 5, 10, &tpgt) || tpgt > UINT_MAX)
1952 return ERR_PTR(-EINVAL);
1954 tpg = kzalloc(sizeof(struct tcm_vhost_tpg), GFP_KERNEL);
1956 pr_err("Unable to allocate struct tcm_vhost_tpg");
1957 return ERR_PTR(-ENOMEM);
1959 mutex_init(&tpg->tv_tpg_mutex);
1960 INIT_LIST_HEAD(&tpg->tv_tpg_list);
1962 tpg->tport_tpgt = tpgt;
1964 ret = core_tpg_register(&tcm_vhost_fabric_configfs->tf_ops, wwn,
1965 &tpg->se_tpg, tpg, TRANSPORT_TPG_TYPE_NORMAL);
1970 mutex_lock(&tcm_vhost_mutex);
1971 list_add_tail(&tpg->tv_tpg_list, &tcm_vhost_list);
1972 mutex_unlock(&tcm_vhost_mutex);
1974 return &tpg->se_tpg;
1977 static void tcm_vhost_drop_tpg(struct se_portal_group *se_tpg)
1979 struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1980 struct tcm_vhost_tpg, se_tpg);
1982 mutex_lock(&tcm_vhost_mutex);
1983 list_del(&tpg->tv_tpg_list);
1984 mutex_unlock(&tcm_vhost_mutex);
1986 * Release the virtual I_T Nexus for this vhost TPG
1988 tcm_vhost_drop_nexus(tpg);
1990 * Deregister the se_tpg from TCM..
1992 core_tpg_deregister(se_tpg);
1996 static struct se_wwn *
1997 tcm_vhost_make_tport(struct target_fabric_configfs *tf,
1998 struct config_group *group,
2001 struct tcm_vhost_tport *tport;
2006 /* if (tcm_vhost_parse_wwn(name, &wwpn, 1) < 0)
2007 return ERR_PTR(-EINVAL); */
2009 tport = kzalloc(sizeof(struct tcm_vhost_tport), GFP_KERNEL);
2011 pr_err("Unable to allocate struct tcm_vhost_tport");
2012 return ERR_PTR(-ENOMEM);
2014 tport->tport_wwpn = wwpn;
2016 * Determine the emulated Protocol Identifier and Target Port Name
2017 * based on the incoming configfs directory name.
2019 ptr = strstr(name, "naa.");
2021 tport->tport_proto_id = SCSI_PROTOCOL_SAS;
2024 ptr = strstr(name, "fc.");
2026 tport->tport_proto_id = SCSI_PROTOCOL_FCP;
2027 off = 3; /* Skip over "fc." */
2030 ptr = strstr(name, "iqn.");
2032 tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
2036 pr_err("Unable to locate prefix for emulated Target Port:"
2039 return ERR_PTR(-EINVAL);
2042 if (strlen(name) >= TCM_VHOST_NAMELEN) {
2043 pr_err("Emulated %s Address: %s, exceeds"
2044 " max: %d\n", name, tcm_vhost_dump_proto_id(tport),
2047 return ERR_PTR(-EINVAL);
2049 snprintf(&tport->tport_name[0], TCM_VHOST_NAMELEN, "%s", &name[off]);
2051 pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target"
2052 " %s Address: %s\n", tcm_vhost_dump_proto_id(tport), name);
2054 return &tport->tport_wwn;
2057 static void tcm_vhost_drop_tport(struct se_wwn *wwn)
2059 struct tcm_vhost_tport *tport = container_of(wwn,
2060 struct tcm_vhost_tport, tport_wwn);
2062 pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target"
2063 " %s Address: %s\n", tcm_vhost_dump_proto_id(tport),
2070 tcm_vhost_wwn_show_attr_version(struct target_fabric_configfs *tf,
2073 return sprintf(page, "TCM_VHOST fabric module %s on %s/%s"
2074 "on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname,
2075 utsname()->machine);
2078 TF_WWN_ATTR_RO(tcm_vhost, version);
2080 static struct configfs_attribute *tcm_vhost_wwn_attrs[] = {
2081 &tcm_vhost_wwn_version.attr,
2085 static struct target_core_fabric_ops tcm_vhost_ops = {
2086 .get_fabric_name = tcm_vhost_get_fabric_name,
2087 .get_fabric_proto_ident = tcm_vhost_get_fabric_proto_ident,
2088 .tpg_get_wwn = tcm_vhost_get_fabric_wwn,
2089 .tpg_get_tag = tcm_vhost_get_tag,
2090 .tpg_get_default_depth = tcm_vhost_get_default_depth,
2091 .tpg_get_pr_transport_id = tcm_vhost_get_pr_transport_id,
2092 .tpg_get_pr_transport_id_len = tcm_vhost_get_pr_transport_id_len,
2093 .tpg_parse_pr_out_transport_id = tcm_vhost_parse_pr_out_transport_id,
2094 .tpg_check_demo_mode = tcm_vhost_check_true,
2095 .tpg_check_demo_mode_cache = tcm_vhost_check_true,
2096 .tpg_check_demo_mode_write_protect = tcm_vhost_check_false,
2097 .tpg_check_prod_mode_write_protect = tcm_vhost_check_false,
2098 .tpg_alloc_fabric_acl = tcm_vhost_alloc_fabric_acl,
2099 .tpg_release_fabric_acl = tcm_vhost_release_fabric_acl,
2100 .tpg_get_inst_index = tcm_vhost_tpg_get_inst_index,
2101 .release_cmd = tcm_vhost_release_cmd,
2102 .check_stop_free = vhost_scsi_check_stop_free,
2103 .shutdown_session = tcm_vhost_shutdown_session,
2104 .close_session = tcm_vhost_close_session,
2105 .sess_get_index = tcm_vhost_sess_get_index,
2106 .sess_get_initiator_sid = NULL,
2107 .write_pending = tcm_vhost_write_pending,
2108 .write_pending_status = tcm_vhost_write_pending_status,
2109 .set_default_node_attributes = tcm_vhost_set_default_node_attrs,
2110 .get_task_tag = tcm_vhost_get_task_tag,
2111 .get_cmd_state = tcm_vhost_get_cmd_state,
2112 .queue_data_in = tcm_vhost_queue_data_in,
2113 .queue_status = tcm_vhost_queue_status,
2114 .queue_tm_rsp = tcm_vhost_queue_tm_rsp,
2116 * Setup callers for generic logic in target_core_fabric_configfs.c
2118 .fabric_make_wwn = tcm_vhost_make_tport,
2119 .fabric_drop_wwn = tcm_vhost_drop_tport,
2120 .fabric_make_tpg = tcm_vhost_make_tpg,
2121 .fabric_drop_tpg = tcm_vhost_drop_tpg,
2122 .fabric_post_link = tcm_vhost_port_link,
2123 .fabric_pre_unlink = tcm_vhost_port_unlink,
2124 .fabric_make_np = NULL,
2125 .fabric_drop_np = NULL,
2126 .fabric_make_nodeacl = tcm_vhost_make_nodeacl,
2127 .fabric_drop_nodeacl = tcm_vhost_drop_nodeacl,
2130 static int tcm_vhost_register_configfs(void)
2132 struct target_fabric_configfs *fabric;
2135 pr_debug("TCM_VHOST fabric module %s on %s/%s"
2136 " on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname,
2137 utsname()->machine);
2139 * Register the top level struct config_item_type with TCM core
2141 fabric = target_fabric_configfs_init(THIS_MODULE, "vhost");
2142 if (IS_ERR(fabric)) {
2143 pr_err("target_fabric_configfs_init() failed\n");
2144 return PTR_ERR(fabric);
2147 * Setup fabric->tf_ops from our local tcm_vhost_ops
2149 fabric->tf_ops = tcm_vhost_ops;
2151 * Setup default attribute lists for various fabric->tf_cit_tmpl
2153 TF_CIT_TMPL(fabric)->tfc_wwn_cit.ct_attrs = tcm_vhost_wwn_attrs;
2154 TF_CIT_TMPL(fabric)->tfc_tpg_base_cit.ct_attrs = tcm_vhost_tpg_attrs;
2155 TF_CIT_TMPL(fabric)->tfc_tpg_attrib_cit.ct_attrs = NULL;
2156 TF_CIT_TMPL(fabric)->tfc_tpg_param_cit.ct_attrs = NULL;
2157 TF_CIT_TMPL(fabric)->tfc_tpg_np_base_cit.ct_attrs = NULL;
2158 TF_CIT_TMPL(fabric)->tfc_tpg_nacl_base_cit.ct_attrs = NULL;
2159 TF_CIT_TMPL(fabric)->tfc_tpg_nacl_attrib_cit.ct_attrs = NULL;
2160 TF_CIT_TMPL(fabric)->tfc_tpg_nacl_auth_cit.ct_attrs = NULL;
2161 TF_CIT_TMPL(fabric)->tfc_tpg_nacl_param_cit.ct_attrs = NULL;
2163 * Register the fabric for use within TCM
2165 ret = target_fabric_configfs_register(fabric);
2167 pr_err("target_fabric_configfs_register() failed"
2168 " for TCM_VHOST\n");
2172 * Setup our local pointer to *fabric
2174 tcm_vhost_fabric_configfs = fabric;
2175 pr_debug("TCM_VHOST[0] - Set fabric -> tcm_vhost_fabric_configfs\n");
2179 static void tcm_vhost_deregister_configfs(void)
2181 if (!tcm_vhost_fabric_configfs)
2184 target_fabric_configfs_deregister(tcm_vhost_fabric_configfs);
2185 tcm_vhost_fabric_configfs = NULL;
2186 pr_debug("TCM_VHOST[0] - Cleared tcm_vhost_fabric_configfs\n");
2189 static int __init tcm_vhost_init(void)
2193 * Use our own dedicated workqueue for submitting I/O into
2194 * target core to avoid contention within system_wq.
2196 tcm_vhost_workqueue = alloc_workqueue("tcm_vhost", 0, 0);
2197 if (!tcm_vhost_workqueue)
2200 ret = vhost_scsi_register();
2202 goto out_destroy_workqueue;
2204 ret = tcm_vhost_register_configfs();
2206 goto out_vhost_scsi_deregister;
2210 out_vhost_scsi_deregister:
2211 vhost_scsi_deregister();
2212 out_destroy_workqueue:
2213 destroy_workqueue(tcm_vhost_workqueue);
2218 static void tcm_vhost_exit(void)
2220 tcm_vhost_deregister_configfs();
2221 vhost_scsi_deregister();
2222 destroy_workqueue(tcm_vhost_workqueue);
2225 MODULE_DESCRIPTION("VHOST_SCSI series fabric driver");
2226 MODULE_ALIAS("tcm_vhost");
2227 MODULE_LICENSE("GPL");
2228 module_init(tcm_vhost_init);
2229 module_exit(tcm_vhost_exit);