/*******************************************************************************
* Vhost kernel TCM fabric driver for virtio SCSI initiators
*
* (C) Copyright 2010-2012 RisingTide Systems LLC.
* (C) Copyright 2010-2012 IBM Corp.
*
* Licensed to the Linux Foundation under the General Public License (GPL) version 2.
*
* Authors: Nicholas A. Bellinger <nab@risingtidesystems.com>
* Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
****************************************************************************/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <generated/utsrelease.h>
#include <linux/utsname.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/kthread.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/configfs.h>
#include <linux/ctype.h>
#include <linux/compat.h>
#include <linux/eventfd.h>
#include <linux/fs.h>
#include <linux/miscdevice.h>
#include <asm/unaligned.h>
#include <scsi/scsi.h>
#include <scsi/scsi_tcq.h>
#include <target/target_core_base.h>
#include <target/target_core_fabric.h>
#include <target/target_core_fabric_configfs.h>
#include <target/target_core_configfs.h>
#include <target/configfs_macros.h>
#include <linux/vhost.h>
#include <linux/virtio_scsi.h>
#include <linux/llist.h>
#include <linux/bitmap.h>
#include "vhost.c"
#include "vhost.h"
#define TCM_VHOST_VERSION "v0.1"
#define TCM_VHOST_NAMELEN 256
#define TCM_VHOST_MAX_CDB_SIZE 32
struct vhost_scsi_inflight {
/* Wait for the flush operation to finish */
struct completion comp;
/* Refcount for the inflight reqs */
struct kref kref;
};
struct tcm_vhost_cmd {
/* Descriptor from vhost_get_vq_desc() for virt_queue segment */
int tvc_vq_desc;
/* virtio-scsi initiator task attribute */
int tvc_task_attr;
/* virtio-scsi initiator data direction */
enum dma_data_direction tvc_data_direction;
/* Expected data transfer length from virtio-scsi header */
u32 tvc_exp_data_len;
/* The Tag from include/linux/virtio_scsi.h:struct virtio_scsi_cmd_req */
u64 tvc_tag;
/* The number of scatterlists associated with this cmd */
u32 tvc_sgl_count;
/* Saved unpacked SCSI LUN for tcm_vhost_submission_work() */
u32 tvc_lun;
/* Pointer to the SGL formatted memory from virtio-scsi */
struct scatterlist *tvc_sgl;
/* Pointer to response */
struct virtio_scsi_cmd_resp __user *tvc_resp;
/* Pointer to vhost_scsi for our device */
struct vhost_scsi *tvc_vhost;
/* Pointer to vhost_virtqueue for the cmd */
struct vhost_virtqueue *tvc_vq;
/* Pointer to vhost nexus memory */
struct tcm_vhost_nexus *tvc_nexus;
/* The TCM I/O descriptor that is accessed via container_of() */
struct se_cmd tvc_se_cmd;
/* work item used for cmwq dispatch to tcm_vhost_submission_work() */
struct work_struct work;
/* Copy of the incoming SCSI command descriptor block (CDB) */
unsigned char tvc_cdb[TCM_VHOST_MAX_CDB_SIZE];
/* Sense buffer that will be mapped into outgoing status */
unsigned char tvc_sense_buf[TRANSPORT_SENSE_BUFFER];
/* Completed commands list, serviced from vhost worker thread */
struct llist_node tvc_completion_list;
/* Used to track inflight cmd */
struct vhost_scsi_inflight *inflight;
};
struct tcm_vhost_nexus {
/* Pointer to TCM session for I_T Nexus */
struct se_session *tvn_se_sess;
};
struct tcm_vhost_nacl {
/* Binary World Wide unique Port Name for Vhost Initiator port */
u64 iport_wwpn;
/* ASCII formatted WWPN for Sas Initiator port */
char iport_name[TCM_VHOST_NAMELEN];
/* Returned by tcm_vhost_make_nodeacl() */
struct se_node_acl se_node_acl;
};
struct vhost_scsi;
struct tcm_vhost_tpg {
/* Vhost port target portal group tag for TCM */
u16 tport_tpgt;
/* Used to track number of TPG Port/Lun Links wrt to explict I_T Nexus shutdown */
int tv_tpg_port_count;
/* Used for vhost_scsi device reference to tpg_nexus, protected by tv_tpg_mutex */
int tv_tpg_vhost_count;
/* list for tcm_vhost_list */
struct list_head tv_tpg_list;
/* Used to protect access for tpg_nexus */
struct mutex tv_tpg_mutex;
/* Pointer to the TCM VHost I_T Nexus for this TPG endpoint */
struct tcm_vhost_nexus *tpg_nexus;
/* Pointer back to tcm_vhost_tport */
struct tcm_vhost_tport *tport;
/* Returned by tcm_vhost_make_tpg() */
struct se_portal_group se_tpg;
/* Pointer back to vhost_scsi, protected by tv_tpg_mutex */
struct vhost_scsi *vhost_scsi;
};
struct tcm_vhost_tport {
/* SCSI protocol the tport is providing */
u8 tport_proto_id;
/* Binary World Wide unique Port Name for Vhost Target port */
u64 tport_wwpn;
/* ASCII formatted WWPN for Vhost Target port */
char tport_name[TCM_VHOST_NAMELEN];
/* Returned by tcm_vhost_make_tport() */
struct se_wwn tport_wwn;
};
struct tcm_vhost_evt {
/* event to be sent to guest */
struct virtio_scsi_event event;
/* event list, serviced from vhost worker thread */
struct llist_node list;
};
enum {
VHOST_SCSI_VQ_CTL = 0,
VHOST_SCSI_VQ_EVT = 1,
VHOST_SCSI_VQ_IO = 2,
};
enum {
VHOST_SCSI_FEATURES = VHOST_FEATURES | (1ULL << VIRTIO_SCSI_F_HOTPLUG)
};
#define VHOST_SCSI_MAX_TARGET 256
#define VHOST_SCSI_MAX_VQ 128
#define VHOST_SCSI_MAX_EVENT 128
struct vhost_scsi_virtqueue {
struct vhost_virtqueue vq;
/*
* Reference counting for inflight reqs, used for flush operation. At
* each time, one reference tracks new commands submitted, while we
* wait for another one to reach 0.
*/
struct vhost_scsi_inflight inflights[2];
/*
* Indicate current inflight in use, protected by vq->mutex.
* Writers must also take dev mutex and flush under it.
*/
int inflight_idx;
};
struct vhost_scsi {
/* Protected by vhost_scsi->dev.mutex */
struct tcm_vhost_tpg **vs_tpg;
char vs_vhost_wwpn[TRANSPORT_IQN_LEN];
struct vhost_dev dev;
struct vhost_scsi_virtqueue vqs[VHOST_SCSI_MAX_VQ];
struct vhost_work vs_completion_work; /* cmd completion work item */
struct llist_head vs_completion_list; /* cmd completion queue */
struct vhost_work vs_event_work; /* evt injection work item */
struct llist_head vs_event_list; /* evt injection queue */
bool vs_events_missed; /* any missed events, protected by vq->mutex */
int vs_events_nr; /* num of pending events, protected by vq->mutex */
};
/* Local pointer to allocated TCM configfs fabric module */
static struct target_fabric_configfs *tcm_vhost_fabric_configfs;
static struct workqueue_struct *tcm_vhost_workqueue;
/* Global spinlock to protect tcm_vhost TPG list for vhost IOCTL access */
static DEFINE_MUTEX(tcm_vhost_mutex);
static LIST_HEAD(tcm_vhost_list);
static int iov_num_pages(struct iovec *iov)
{
return (PAGE_ALIGN((unsigned long)iov->iov_base + iov->iov_len) -
((unsigned long)iov->iov_base & PAGE_MASK)) >> PAGE_SHIFT;
}
void tcm_vhost_done_inflight(struct kref *kref)
{
struct vhost_scsi_inflight *inflight;
inflight = container_of(kref, struct vhost_scsi_inflight, kref);
complete(&inflight->comp);
}
static void tcm_vhost_init_inflight(struct vhost_scsi *vs,
struct vhost_scsi_inflight *old_inflight[])
{
struct vhost_scsi_inflight *new_inflight;
struct vhost_virtqueue *vq;
int idx, i;
for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
vq = &vs->vqs[i].vq;
mutex_lock(&vq->mutex);
/* store old infight */
idx = vs->vqs[i].inflight_idx;
if (old_inflight)
old_inflight[i] = &vs->vqs[i].inflights[idx];
/* setup new infight */
vs->vqs[i].inflight_idx = idx ^ 1;
new_inflight = &vs->vqs[i].inflights[idx ^ 1];
kref_init(&new_inflight->kref);
init_completion(&new_inflight->comp);
mutex_unlock(&vq->mutex);
}
}
static struct vhost_scsi_inflight *
tcm_vhost_get_inflight(struct vhost_virtqueue *vq)
{
struct vhost_scsi_inflight *inflight;
struct vhost_scsi_virtqueue *svq;
svq = container_of(vq, struct vhost_scsi_virtqueue, vq);
inflight = &svq->inflights[svq->inflight_idx];
kref_get(&inflight->kref);
return inflight;
}
static void tcm_vhost_put_inflight(struct vhost_scsi_inflight *inflight)
{
kref_put(&inflight->kref, tcm_vhost_done_inflight);
}
static int tcm_vhost_check_true(struct se_portal_group *se_tpg)
{
return 1;
}
static int tcm_vhost_check_false(struct se_portal_group *se_tpg)
{
return 0;
}
static char *tcm_vhost_get_fabric_name(void)
{
return "vhost";
}
static u8 tcm_vhost_get_fabric_proto_ident(struct se_portal_group *se_tpg)
{
struct tcm_vhost_tpg *tpg = container_of(se_tpg,
struct tcm_vhost_tpg, se_tpg);
struct tcm_vhost_tport *tport = tpg->tport;
switch (tport->tport_proto_id) {
case SCSI_PROTOCOL_SAS:
return sas_get_fabric_proto_ident(se_tpg);
case SCSI_PROTOCOL_FCP:
return fc_get_fabric_proto_ident(se_tpg);
case SCSI_PROTOCOL_ISCSI:
return iscsi_get_fabric_proto_ident(se_tpg);
default:
pr_err("Unknown tport_proto_id: 0x%02x, using"
" SAS emulation\n", tport->tport_proto_id);
break;
}
return sas_get_fabric_proto_ident(se_tpg);
}
static char *tcm_vhost_get_fabric_wwn(struct se_portal_group *se_tpg)
{
struct tcm_vhost_tpg *tpg = container_of(se_tpg,
struct tcm_vhost_tpg, se_tpg);
struct tcm_vhost_tport *tport = tpg->tport;
return &tport->tport_name[0];
}
static u16 tcm_vhost_get_tag(struct se_portal_group *se_tpg)
{
struct tcm_vhost_tpg *tpg = container_of(se_tpg,
struct tcm_vhost_tpg, se_tpg);
return tpg->tport_tpgt;
}
static u32 tcm_vhost_get_default_depth(struct se_portal_group *se_tpg)
{
return 1;
}
static u32 tcm_vhost_get_pr_transport_id(struct se_portal_group *se_tpg,
struct se_node_acl *se_nacl,
struct t10_pr_registration *pr_reg,
int *format_code,
unsigned char *buf)
{
struct tcm_vhost_tpg *tpg = container_of(se_tpg,
struct tcm_vhost_tpg, se_tpg);
struct tcm_vhost_tport *tport = tpg->tport;
switch (tport->tport_proto_id) {
case SCSI_PROTOCOL_SAS:
return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
format_code, buf);
case SCSI_PROTOCOL_FCP:
return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
format_code, buf);
case SCSI_PROTOCOL_ISCSI:
return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
format_code, buf);
default:
pr_err("Unknown tport_proto_id: 0x%02x, using"
" SAS emulation\n", tport->tport_proto_id);
break;
}
return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
format_code, buf);
}
static u32 tcm_vhost_get_pr_transport_id_len(struct se_portal_group *se_tpg,
struct se_node_acl *se_nacl,
struct t10_pr_registration *pr_reg,
int *format_code)
{
struct tcm_vhost_tpg *tpg = container_of(se_tpg,
struct tcm_vhost_tpg, se_tpg);
struct tcm_vhost_tport *tport = tpg->tport;
switch (tport->tport_proto_id) {
case SCSI_PROTOCOL_SAS:
return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
format_code);
case SCSI_PROTOCOL_FCP:
return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
format_code);
case SCSI_PROTOCOL_ISCSI:
return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
format_code);
default:
pr_err("Unknown tport_proto_id: 0x%02x, using"
" SAS emulation\n", tport->tport_proto_id);
break;
}
return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
format_code);
}
static char *tcm_vhost_parse_pr_out_transport_id(struct se_portal_group *se_tpg,
const char *buf,
u32 *out_tid_len,
char **port_nexus_ptr)
{
struct tcm_vhost_tpg *tpg = container_of(se_tpg,
struct tcm_vhost_tpg, se_tpg);
struct tcm_vhost_tport *tport = tpg->tport;
switch (tport->tport_proto_id) {
case SCSI_PROTOCOL_SAS:
return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
port_nexus_ptr);
case SCSI_PROTOCOL_FCP:
return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
port_nexus_ptr);
case SCSI_PROTOCOL_ISCSI:
return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
port_nexus_ptr);
default:
pr_err("Unknown tport_proto_id: 0x%02x, using"
" SAS emulation\n", tport->tport_proto_id);
break;
}
return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
port_nexus_ptr);
}
static struct se_node_acl *tcm_vhost_alloc_fabric_acl(
struct se_portal_group *se_tpg)
{
struct tcm_vhost_nacl *nacl;
nacl = kzalloc(sizeof(struct tcm_vhost_nacl), GFP_KERNEL);
if (!nacl) {
pr_err("Unable to allocate struct tcm_vhost_nacl\n");
return NULL;
}
return &nacl->se_node_acl;
}
static void tcm_vhost_release_fabric_acl(struct se_portal_group *se_tpg,
struct se_node_acl *se_nacl)
{
struct tcm_vhost_nacl *nacl = container_of(se_nacl,
struct tcm_vhost_nacl, se_node_acl);
kfree(nacl);
}
static u32 tcm_vhost_tpg_get_inst_index(struct se_portal_group *se_tpg)
{
return 1;
}
static void tcm_vhost_release_cmd(struct se_cmd *se_cmd)
{
return;
}
static int tcm_vhost_shutdown_session(struct se_session *se_sess)
{
return 0;
}
static void tcm_vhost_close_session(struct se_session *se_sess)
{
return;
}
static u32 tcm_vhost_sess_get_index(struct se_session *se_sess)
{
return 0;
}
static int tcm_vhost_write_pending(struct se_cmd *se_cmd)
{
/* Go ahead and process the write immediately */
target_execute_cmd(se_cmd);
return 0;
}
static int tcm_vhost_write_pending_status(struct se_cmd *se_cmd)
{
return 0;
}
static void tcm_vhost_set_default_node_attrs(struct se_node_acl *nacl)
{
return;
}
static u32 tcm_vhost_get_task_tag(struct se_cmd *se_cmd)
{
return 0;
}
static int tcm_vhost_get_cmd_state(struct se_cmd *se_cmd)
{
return 0;
}
static void vhost_scsi_complete_cmd(struct tcm_vhost_cmd *tv_cmd)
{
struct vhost_scsi *vs = tv_cmd->tvc_vhost;
llist_add(&tv_cmd->tvc_completion_list, &vs->vs_completion_list);
vhost_work_queue(&vs->dev, &vs->vs_completion_work);
}
static int tcm_vhost_queue_data_in(struct se_cmd *se_cmd)
{
struct tcm_vhost_cmd *tv_cmd = container_of(se_cmd,
struct tcm_vhost_cmd, tvc_se_cmd);
vhost_scsi_complete_cmd(tv_cmd);
return 0;
}
static int tcm_vhost_queue_status(struct se_cmd *se_cmd)
{
struct tcm_vhost_cmd *tv_cmd = container_of(se_cmd,
struct tcm_vhost_cmd, tvc_se_cmd);
vhost_scsi_complete_cmd(tv_cmd);
return 0;
}
static int tcm_vhost_queue_tm_rsp(struct se_cmd *se_cmd)
{
return 0;
}
static void tcm_vhost_free_evt(struct vhost_scsi *vs, struct tcm_vhost_evt *evt)
{
vs->vs_events_nr--;
kfree(evt);
}
static struct tcm_vhost_evt *tcm_vhost_allocate_evt(struct vhost_scsi *vs,
u32 event, u32 reason)
{
struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
struct tcm_vhost_evt *evt;
if (vs->vs_events_nr > VHOST_SCSI_MAX_EVENT) {
vs->vs_events_missed = true;
return NULL;
}
evt = kzalloc(sizeof(*evt), GFP_KERNEL);
if (!evt) {
vq_err(vq, "Failed to allocate tcm_vhost_evt\n");
vs->vs_events_missed = true;
return NULL;
}
evt->event.event = event;
evt->event.reason = reason;
vs->vs_events_nr++;
return evt;
}
static void vhost_scsi_free_cmd(struct tcm_vhost_cmd *tv_cmd)
{
struct se_cmd *se_cmd = &tv_cmd->tvc_se_cmd;
/* TODO locking against target/backend threads? */
transport_generic_free_cmd(se_cmd, 1);
if (tv_cmd->tvc_sgl_count) {
u32 i;
for (i = 0; i < tv_cmd->tvc_sgl_count; i++)
put_page(sg_page(&tv_cmd->tvc_sgl[i]));
kfree(tv_cmd->tvc_sgl);
}
tcm_vhost_put_inflight(tv_cmd->inflight);
kfree(tv_cmd);
}
static void tcm_vhost_do_evt_work(struct vhost_scsi *vs,
struct tcm_vhost_evt *evt)
{
struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
struct virtio_scsi_event *event = &evt->event;
struct virtio_scsi_event __user *eventp;
unsigned out, in;
int head, ret;
if (!vq->private_data) {
vs->vs_events_missed = true;
return;
}
again:
vhost_disable_notify(&vs->dev, vq);
head = vhost_get_vq_desc(&vs->dev, vq, vq->iov,
ARRAY_SIZE(vq->iov), &out, &in,
NULL, NULL);
if (head < 0) {
vs->vs_events_missed = true;
return;
}
if (head == vq->num) {
if (vhost_enable_notify(&vs->dev, vq))
goto again;
vs->vs_events_missed = true;
return;
}
if ((vq->iov[out].iov_len != sizeof(struct virtio_scsi_event))) {
vq_err(vq, "Expecting virtio_scsi_event, got %zu bytes\n",
vq->iov[out].iov_len);
vs->vs_events_missed = true;
return;
}
if (vs->vs_events_missed) {
event->event |= VIRTIO_SCSI_T_EVENTS_MISSED;
vs->vs_events_missed = false;
}
eventp = vq->iov[out].iov_base;
ret = __copy_to_user(eventp, event, sizeof(*event));
if (!ret)
vhost_add_used_and_signal(&vs->dev, vq, head, 0);
else
vq_err(vq, "Faulted on tcm_vhost_send_event\n");
}
static void tcm_vhost_evt_work(struct vhost_work *work)
{
struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
vs_event_work);
struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
struct tcm_vhost_evt *evt;
struct llist_node *llnode;
mutex_lock(&vq->mutex);
llnode = llist_del_all(&vs->vs_event_list);
while (llnode) {
evt = llist_entry(llnode, struct tcm_vhost_evt, list);
llnode = llist_next(llnode);
tcm_vhost_do_evt_work(vs, evt);
tcm_vhost_free_evt(vs, evt);
}
mutex_unlock(&vq->mutex);
}
/* Fill in status and signal that we are done processing this command
*
* This is scheduled in the vhost work queue so we are called with the owner
* process mm and can access the vring.
*/
static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
{
struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
vs_completion_work);
DECLARE_BITMAP(signal, VHOST_SCSI_MAX_VQ);
struct virtio_scsi_cmd_resp v_rsp;
struct tcm_vhost_cmd *tv_cmd;
struct llist_node *llnode;
struct se_cmd *se_cmd;
int ret, vq;
bitmap_zero(signal, VHOST_SCSI_MAX_VQ);
llnode = llist_del_all(&vs->vs_completion_list);
while (llnode) {
tv_cmd = llist_entry(llnode, struct tcm_vhost_cmd,
tvc_completion_list);
llnode = llist_next(llnode);
se_cmd = &tv_cmd->tvc_se_cmd;
pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__,
tv_cmd, se_cmd->residual_count, se_cmd->scsi_status);
memset(&v_rsp, 0, sizeof(v_rsp));
v_rsp.resid = se_cmd->residual_count;
/* TODO is status_qualifier field needed? */
v_rsp.status = se_cmd->scsi_status;
v_rsp.sense_len = se_cmd->scsi_sense_length;
memcpy(v_rsp.sense, tv_cmd->tvc_sense_buf,
v_rsp.sense_len);
ret = copy_to_user(tv_cmd->tvc_resp, &v_rsp, sizeof(v_rsp));
if (likely(ret == 0)) {
struct vhost_scsi_virtqueue *q;
vhost_add_used(tv_cmd->tvc_vq, tv_cmd->tvc_vq_desc, 0);
q = container_of(tv_cmd->tvc_vq, struct vhost_scsi_virtqueue, vq);
vq = q - vs->vqs;
__set_bit(vq, signal);
} else
pr_err("Faulted on virtio_scsi_cmd_resp\n");
vhost_scsi_free_cmd(tv_cmd);
}
vq = -1;
while ((vq = find_next_bit(signal, VHOST_SCSI_MAX_VQ, vq + 1))
< VHOST_SCSI_MAX_VQ)
vhost_signal(&vs->dev, &vs->vqs[vq].vq);
}
static struct tcm_vhost_cmd *vhost_scsi_allocate_cmd(
struct vhost_virtqueue *vq,
struct tcm_vhost_tpg *tv_tpg,
struct virtio_scsi_cmd_req *v_req,
u32 exp_data_len,
int data_direction)
{
struct tcm_vhost_cmd *tv_cmd;
struct tcm_vhost_nexus *tv_nexus;
tv_nexus = tv_tpg->tpg_nexus;
if (!tv_nexus) {
pr_err("Unable to locate active struct tcm_vhost_nexus\n");
return ERR_PTR(-EIO);
}
tv_cmd = kzalloc(sizeof(struct tcm_vhost_cmd), GFP_ATOMIC);
if (!tv_cmd) {
pr_err("Unable to allocate struct tcm_vhost_cmd\n");
return ERR_PTR(-ENOMEM);
}
tv_cmd->tvc_tag = v_req->tag;
tv_cmd->tvc_task_attr = v_req->task_attr;
tv_cmd->tvc_exp_data_len = exp_data_len;
tv_cmd->tvc_data_direction = data_direction;
tv_cmd->tvc_nexus = tv_nexus;
tv_cmd->inflight = tcm_vhost_get_inflight(vq);
return tv_cmd;
}
/*
* Map a user memory range into a scatterlist
*
* Returns the number of scatterlist entries used or -errno on error.
*/
static int vhost_scsi_map_to_sgl(struct scatterlist *sgl,
unsigned int sgl_count, struct iovec *iov, int write)
{
unsigned int npages = 0, pages_nr, offset, nbytes;
struct scatterlist *sg = sgl;
void __user *ptr = iov->iov_base;
size_t len = iov->iov_len;
struct page **pages;
int ret, i;
pages_nr = iov_num_pages(iov);
if (pages_nr > sgl_count)
return -ENOBUFS;
pages = kmalloc(pages_nr * sizeof(struct page *), GFP_KERNEL);
if (!pages)
return -ENOMEM;
ret = get_user_pages_fast((unsigned long)ptr, pages_nr, write, pages);
/* No pages were pinned */
if (ret < 0)
goto out;
/* Less pages pinned than wanted */
if (ret != pages_nr) {
for (i = 0; i < ret; i++)
put_page(pages[i]);
ret = -EFAULT;
goto out;
}
while (len > 0) {
offset = (uintptr_t)ptr & ~PAGE_MASK;
nbytes = min_t(unsigned int, PAGE_SIZE - offset, len);
sg_set_page(sg, pages[npages], nbytes, offset);
ptr += nbytes;
len -= nbytes;
sg++;
npages++;
}
out:
kfree(pages);
return ret;
}
static int vhost_scsi_map_iov_to_sgl(struct tcm_vhost_cmd *tv_cmd,
struct iovec *iov, unsigned int niov, int write)
{
int ret;
unsigned int i;
u32 sgl_count;
struct scatterlist *sg;
/*
* Find out how long sglist needs to be
*/
sgl_count = 0;
for (i = 0; i < niov; i++)
sgl_count += iov_num_pages(&iov[i]);
/* TODO overflow checking */
sg = kmalloc(sizeof(tv_cmd->tvc_sgl[0]) * sgl_count, GFP_ATOMIC);
if (!sg)
return -ENOMEM;
pr_debug("%s sg %p sgl_count %u is_err %d\n", __func__,
sg, sgl_count, !sg);
sg_init_table(sg, sgl_count);
tv_cmd->tvc_sgl = sg;
tv_cmd->tvc_sgl_count = sgl_count;
pr_debug("Mapping %u iovecs for %u pages\n", niov, sgl_count);
for (i = 0; i < niov; i++) {
ret = vhost_scsi_map_to_sgl(sg, sgl_count, &iov[i], write);
if (ret < 0) {
for (i = 0; i < tv_cmd->tvc_sgl_count; i++)
put_page(sg_page(&tv_cmd->tvc_sgl[i]));
kfree(tv_cmd->tvc_sgl);
tv_cmd->tvc_sgl = NULL;
tv_cmd->tvc_sgl_count = 0;
return ret;
}
sg += ret;
sgl_count -= ret;
}
return 0;
}
static void tcm_vhost_submission_work(struct work_struct *work)
{
struct tcm_vhost_cmd *tv_cmd =
container_of(work, struct tcm_vhost_cmd, work);
struct tcm_vhost_nexus *tv_nexus;
struct se_cmd *se_cmd = &tv_cmd->tvc_se_cmd;
struct scatterlist *sg_ptr, *sg_bidi_ptr = NULL;
int rc, sg_no_bidi = 0;
if (tv_cmd->tvc_sgl_count) {
sg_ptr = tv_cmd->tvc_sgl;
/* FIXME: Fix BIDI operation in tcm_vhost_submission_work() */
#if 0
if (se_cmd->se_cmd_flags & SCF_BIDI) {
sg_bidi_ptr = NULL;
sg_no_bidi = 0;
}
#endif
} else {
sg_ptr = NULL;
}
tv_nexus = tv_cmd->tvc_nexus;
rc = target_submit_cmd_map_sgls(se_cmd, tv_nexus->tvn_se_sess,
tv_cmd->tvc_cdb, &tv_cmd->tvc_sense_buf[0],
tv_cmd->tvc_lun, tv_cmd->tvc_exp_data_len,
tv_cmd->tvc_task_attr, tv_cmd->tvc_data_direction,
0, sg_ptr, tv_cmd->tvc_sgl_count,
sg_bidi_ptr, sg_no_bidi);
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 void vhost_scsi_send_bad_target(struct vhost_scsi *vs,
struct vhost_virtqueue *vq, int head, unsigned out)
{
struct virtio_scsi_cmd_resp __user *resp;
struct virtio_scsi_cmd_resp rsp;
int ret;
memset(&rsp, 0, sizeof(rsp));
rsp.response = VIRTIO_SCSI_S_BAD_TARGET;
resp = vq->iov[out].iov_base;
ret = __copy_to_user(resp, &rsp, sizeof(rsp));
if (!ret)
vhost_add_used_and_signal(&vs->dev, vq, head, 0);
else
pr_err("Faulted on virtio_scsi_cmd_resp\n");
}
static void vhost_scsi_handle_vq(struct vhost_scsi *vs,
struct vhost_virtqueue *vq)
{
struct tcm_vhost_tpg **vs_tpg;
struct virtio_scsi_cmd_req v_req;
struct tcm_vhost_tpg *tv_tpg;
struct tcm_vhost_cmd *tv_cmd;
u32 exp_data_len, data_first, data_num, data_direction;
unsigned out, in, i;
int head, ret;
u8 target;
/*
* We can handle the vq only after the endpoint is setup by calling the
* VHOST_SCSI_SET_ENDPOINT ioctl.
*
* TODO: Check that we are running from vhost_worker which acts
* as read-side critical section for vhost kind of RCU.
* See the comments in struct vhost_virtqueue in drivers/vhost/vhost.h
*/
vs_tpg = rcu_dereference_check(vq->private_data, 1);
if (!vs_tpg)
return;
mutex_lock(&vq->mutex);
vhost_disable_notify(&vs->dev, vq);
for (;;) {
head = vhost_get_vq_desc(&vs->dev, vq, vq->iov,
ARRAY_SIZE(vq->iov), &out, &in,
NULL, NULL);
pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n",
head, out, in);
/* On error, stop handling until the next kick. */
if (unlikely(head < 0))
break;
/* Nothing new? Wait for eventfd to tell us they refilled. */
if (head == vq->num) {
if (unlikely(vhost_enable_notify(&vs->dev, vq))) {
vhost_disable_notify(&vs->dev, vq);
continue;
}
break;
}
/* FIXME: BIDI operation */
if (out == 1 && in == 1) {
data_direction = DMA_NONE;
data_first = 0;
data_num = 0;
} else if (out == 1 && in > 1) {
data_direction = DMA_FROM_DEVICE;
data_first = out + 1;
data_num = in - 1;
} else if (out > 1 && in == 1) {
data_direction = DMA_TO_DEVICE;
data_first = 1;
data_num = out - 1;
} else {
vq_err(vq, "Invalid buffer layout out: %u in: %u\n",
out, in);
break;
}
/*
* Check for a sane resp buffer so we can report errors to
* the guest.
*/
if (unlikely(vq->iov[out].iov_len !=
sizeof(struct virtio_scsi_cmd_resp))) {
vq_err(vq, "Expecting virtio_scsi_cmd_resp, got %zu"
" bytes\n", vq->iov[out].iov_len);
break;
}
if (unlikely(vq->iov[0].iov_len != sizeof(v_req))) {
vq_err(vq, "Expecting virtio_scsi_cmd_req, got %zu"
" bytes\n", vq->iov[0].iov_len);
break;
}
pr_debug("Calling __copy_from_user: vq->iov[0].iov_base: %p,"
" len: %zu\n", vq->iov[0].iov_base, sizeof(v_req));
ret = __copy_from_user(&v_req, vq->iov[0].iov_base,
sizeof(v_req));
if (unlikely(ret)) {
vq_err(vq, "Faulted on virtio_scsi_cmd_req\n");
break;
}
/* Extract the tpgt */
target = v_req.lun[1];
tv_tpg = ACCESS_ONCE(vs_tpg[target]);
/* Target does not exist, fail the request */
if (unlikely(!tv_tpg)) {
vhost_scsi_send_bad_target(vs, vq, head, out);
continue;
}
exp_data_len = 0;
for (i = 0; i < data_num; i++)
exp_data_len += vq->iov[data_first + i].iov_len;
tv_cmd = vhost_scsi_allocate_cmd(vq, tv_tpg, &v_req,
exp_data_len, data_direction);
if (IS_ERR(tv_cmd)) {
vq_err(vq, "vhost_scsi_allocate_cmd failed %ld\n",
PTR_ERR(tv_cmd));
goto err_cmd;
}
pr_debug("Allocated tv_cmd: %p exp_data_len: %d, data_direction"
": %d\n", tv_cmd, exp_data_len, data_direction);
tv_cmd->tvc_vhost = vs;
tv_cmd->tvc_vq = vq;
tv_cmd->tvc_resp = vq->iov[out].iov_base;
/*
* Copy in the recieved CDB descriptor into tv_cmd->tvc_cdb
* that will be used by tcm_vhost_new_cmd_map() and down into
* target_setup_cmd_from_cdb()
*/
memcpy(tv_cmd->tvc_cdb, v_req.cdb, TCM_VHOST_MAX_CDB_SIZE);
/*
* Check that the recieved CDB size does not exceeded our
* hardcoded max for tcm_vhost
*/
/* TODO what if cdb was too small for varlen cdb header? */
if (unlikely(scsi_command_size(tv_cmd->tvc_cdb) >
TCM_VHOST_MAX_CDB_SIZE)) {
vq_err(vq, "Received SCSI CDB with command_size: %d that"
" exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
scsi_command_size(tv_cmd->tvc_cdb),
TCM_VHOST_MAX_CDB_SIZE);
goto err_free;
}
tv_cmd->tvc_lun = ((v_req.lun[2] << 8) | v_req.lun[3]) & 0x3FFF;
pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n",
tv_cmd->tvc_cdb[0], tv_cmd->tvc_lun);
if (data_direction != DMA_NONE) {
ret = vhost_scsi_map_iov_to_sgl(tv_cmd,
&vq->iov[data_first], data_num,
data_direction == DMA_TO_DEVICE);
if (unlikely(ret)) {
vq_err(vq, "Failed to map iov to sgl\n");
goto err_free;
}
}
/*
* Save the descriptor from vhost_get_vq_desc() to be used to
* complete the virtio-scsi request in TCM callback context via
* tcm_vhost_queue_data_in() and tcm_vhost_queue_status()
*/
tv_cmd->tvc_vq_desc = head;
/*
* Dispatch tv_cmd descriptor for cmwq execution in process
* context provided by tcm_vhost_workqueue. This also ensures
* tv_cmd is executed on the same kworker CPU as this vhost
* thread to gain positive L2 cache locality effects..
*/
INIT_WORK(&tv_cmd->work, tcm_vhost_submission_work);
queue_work(tcm_vhost_workqueue, &tv_cmd->work);
}
mutex_unlock(&vq->mutex);
return;
err_free:
vhost_scsi_free_cmd(tv_cmd);
err_cmd:
vhost_scsi_send_bad_target(vs, vq, head, out);
mutex_unlock(&vq->mutex);
}
static void vhost_scsi_ctl_handle_kick(struct vhost_work *work)
{
pr_debug("%s: The handling func for control queue.\n", __func__);
}
static void tcm_vhost_send_evt(struct vhost_scsi *vs, struct tcm_vhost_tpg *tpg,
struct se_lun *lun, u32 event, u32 reason)
{
struct tcm_vhost_evt *evt;
evt = tcm_vhost_allocate_evt(vs, event, reason);
if (!evt)
return;
if (tpg && lun) {
/* TODO: share lun setup code with virtio-scsi.ko */
/*
* Note: evt->event is zeroed when we allocate it and
* lun[4-7] need to be zero according to virtio-scsi spec.
*/
evt->event.lun[0] = 0x01;
evt->event.lun[1] = tpg->tport_tpgt & 0xFF;
if (lun->unpacked_lun >= 256)
evt->event.lun[2] = lun->unpacked_lun >> 8 | 0x40 ;
evt->event.lun[3] = lun->unpacked_lun & 0xFF;
}
llist_add(&evt->list, &vs->vs_event_list);
vhost_work_queue(&vs->dev, &vs->vs_event_work);
}
static void vhost_scsi_evt_handle_kick(struct vhost_work *work)
{
struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
poll.work);
struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
mutex_lock(&vq->mutex);
if (!vq->private_data)
goto out;
if (vs->vs_events_missed)
tcm_vhost_send_evt(vs, NULL, NULL, VIRTIO_SCSI_T_NO_EVENT, 0);
out:
mutex_unlock(&vq->mutex);
}
static void vhost_scsi_handle_kick(struct vhost_work *work)
{
struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
poll.work);
struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
vhost_scsi_handle_vq(vs, vq);
}
static void vhost_scsi_flush_vq(struct vhost_scsi *vs, int index)
{
vhost_poll_flush(&vs->vqs[index].vq.poll);
}
/* Callers must hold dev mutex */
static void vhost_scsi_flush(struct vhost_scsi *vs)
{
struct vhost_scsi_inflight *old_inflight[VHOST_SCSI_MAX_VQ];
int i;
/* Init new inflight and remember the old inflight */
tcm_vhost_init_inflight(vs, old_inflight);
/*
* The inflight->kref was initialized to 1. We decrement it here to
* indicate the start of the flush operation so that it will reach 0
* when all the reqs are finished.
*/
for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
kref_put(&old_inflight[i]->kref, tcm_vhost_done_inflight);
/* Flush both the vhost poll and vhost work */
for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
vhost_scsi_flush_vq(vs, i);
vhost_work_flush(&vs->dev, &vs->vs_completion_work);
vhost_work_flush(&vs->dev, &vs->vs_event_work);
/* Wait for all reqs issued before the flush to be finished */
for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
wait_for_completion(&old_inflight[i]->comp);
}
/*
* Called from vhost_scsi_ioctl() context to walk the list of available
* tcm_vhost_tpg with an active struct tcm_vhost_nexus
*
* The lock nesting rule is:
* tcm_vhost_mutex -> vs->dev.mutex -> tpg->tv_tpg_mutex -> vq->mutex
*/
static int vhost_scsi_set_endpoint(
struct vhost_scsi *vs,
struct vhost_scsi_target *t)
{
struct tcm_vhost_tport *tv_tport;
struct tcm_vhost_tpg *tv_tpg;
struct tcm_vhost_tpg **vs_tpg;
struct vhost_virtqueue *vq;
int index, ret, i, len;
bool match = false;
mutex_lock(&tcm_vhost_mutex);
mutex_lock(&vs->dev.mutex);
/* Verify that ring has been setup correctly. */
for (index = 0; index < vs->dev.nvqs; ++index) {
/* Verify that ring has been setup correctly. */
if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
ret = -EFAULT;
goto out;
}
}
len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET;
vs_tpg = kzalloc(len, GFP_KERNEL);
if (!vs_tpg) {
ret = -ENOMEM;
goto out;
}
if (vs->vs_tpg)
memcpy(vs_tpg, vs->vs_tpg, len);
list_for_each_entry(tv_tpg, &tcm_vhost_list, tv_tpg_list) {
mutex_lock(&tv_tpg->tv_tpg_mutex);
if (!tv_tpg->tpg_nexus) {
mutex_unlock(&tv_tpg->tv_tpg_mutex);
continue;
}
if (tv_tpg->tv_tpg_vhost_count != 0) {
mutex_unlock(&tv_tpg->tv_tpg_mutex);
continue;
}
tv_tport = tv_tpg->tport;
if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
if (vs->vs_tpg && vs->vs_tpg[tv_tpg->tport_tpgt]) {
kfree(vs_tpg);
mutex_unlock(&tv_tpg->tv_tpg_mutex);
ret = -EEXIST;
goto out;
}
tv_tpg->tv_tpg_vhost_count++;
tv_tpg->vhost_scsi = vs;
vs_tpg[tv_tpg->tport_tpgt] = tv_tpg;
smp_mb__after_atomic_inc();
match = true;
}
mutex_unlock(&tv_tpg->tv_tpg_mutex);
}
if (match) {
memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
sizeof(vs->vs_vhost_wwpn));
for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
vq = &vs->vqs[i].vq;
/* Flushing the vhost_work acts as synchronize_rcu */
mutex_lock(&vq->mutex);
rcu_assign_pointer(vq->private_data, vs_tpg);
vhost_init_used(vq);
mutex_unlock(&vq->mutex);
}
ret = 0;
} else {
ret = -EEXIST;
}
/*
* Act as synchronize_rcu to make sure access to
* old vs->vs_tpg is finished.
*/
vhost_scsi_flush(vs);
kfree(vs->vs_tpg);
vs->vs_tpg = vs_tpg;
out:
mutex_unlock(&vs->dev.mutex);
mutex_unlock(&tcm_vhost_mutex);
return ret;
}
static int vhost_scsi_clear_endpoint(
struct vhost_scsi *vs,
struct vhost_scsi_target *t)
{
struct tcm_vhost_tport *tv_tport;
struct tcm_vhost_tpg *tv_tpg;
struct vhost_virtqueue *vq;
bool match = false;
int index, ret, i;
u8 target;
mutex_lock(&tcm_vhost_mutex);
mutex_lock(&vs->dev.mutex);
/* Verify that ring has been setup correctly. */
for (index = 0; index < vs->dev.nvqs; ++index) {
if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
ret = -EFAULT;
goto err_dev;
}
}
if (!vs->vs_tpg) {
ret = 0;
goto err_dev;
}
for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
target = i;
tv_tpg = vs->vs_tpg[target];
if (!tv_tpg)
continue;
mutex_lock(&tv_tpg->tv_tpg_mutex);
tv_tport = tv_tpg->tport;
if (!tv_tport) {
ret = -ENODEV;
goto err_tpg;
}
if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
pr_warn("tv_tport->tport_name: %s, tv_tpg->tport_tpgt: %hu"
" does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
tv_tport->tport_name, tv_tpg->tport_tpgt,
t->vhost_wwpn, t->vhost_tpgt);
ret = -EINVAL;
goto err_tpg;
}
tv_tpg->tv_tpg_vhost_count--;
tv_tpg->vhost_scsi = NULL;
vs->vs_tpg[target] = NULL;
match = true;
mutex_unlock(&tv_tpg->tv_tpg_mutex);
}
if (match) {
for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
vq = &vs->vqs[i].vq;
/* Flushing the vhost_work acts as synchronize_rcu */
mutex_lock(&vq->mutex);
rcu_assign_pointer(vq->private_data, NULL);
mutex_unlock(&vq->mutex);
}
}
/*
* Act as synchronize_rcu to make sure access to
* old vs->vs_tpg is finished.
*/
vhost_scsi_flush(vs);
kfree(vs->vs_tpg);
vs->vs_tpg = NULL;
WARN_ON(vs->vs_events_nr);
mutex_unlock(&vs->dev.mutex);
mutex_unlock(&tcm_vhost_mutex);
return 0;
err_tpg:
mutex_unlock(&tv_tpg->tv_tpg_mutex);
err_dev:
mutex_unlock(&vs->dev.mutex);
mutex_unlock(&tcm_vhost_mutex);
return ret;
}
static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features)
{
if (features & ~VHOST_SCSI_FEATURES)
return -EOPNOTSUPP;
mutex_lock(&vs->dev.mutex);
if ((features & (1 << VHOST_F_LOG_ALL)) &&
!vhost_log_access_ok(&vs->dev)) {
mutex_unlock(&vs->dev.mutex);
return -EFAULT;
}
vs->dev.acked_features = features;
smp_wmb();
vhost_scsi_flush(vs);
mutex_unlock(&vs->dev.mutex);
return 0;
}
static int vhost_scsi_open(struct inode *inode, struct file *f)
{
struct vhost_scsi *s;
struct vhost_virtqueue **vqs;
int r, i;
s = kzalloc(sizeof(*s), GFP_KERNEL);
if (!s)
return -ENOMEM;
vqs = kmalloc(VHOST_SCSI_MAX_VQ * sizeof(*vqs), GFP_KERNEL);
if (!vqs) {
kfree(s);
return -ENOMEM;
}
vhost_work_init(&s->vs_completion_work, vhost_scsi_complete_cmd_work);
vhost_work_init(&s->vs_event_work, tcm_vhost_evt_work);
s->vs_events_nr = 0;
s->vs_events_missed = false;
vqs[VHOST_SCSI_VQ_CTL] = &s->vqs[VHOST_SCSI_VQ_CTL].vq;
vqs[VHOST_SCSI_VQ_EVT] = &s->vqs[VHOST_SCSI_VQ_EVT].vq;
s->vqs[VHOST_SCSI_VQ_CTL].vq.handle_kick = vhost_scsi_ctl_handle_kick;
s->vqs[VHOST_SCSI_VQ_EVT].vq.handle_kick = vhost_scsi_evt_handle_kick;
for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++) {
vqs[i] = &s->vqs[i].vq;
s->vqs[i].vq.handle_kick = vhost_scsi_handle_kick;
}
r = vhost_dev_init(&s->dev, vqs, VHOST_SCSI_MAX_VQ);
tcm_vhost_init_inflight(s, NULL);
if (r < 0) {
kfree(vqs);
kfree(s);
return r;
}
f->private_data = s;
return 0;
}
static int vhost_scsi_release(struct inode *inode, struct file *f)
{
struct vhost_scsi *s = f->private_data;
struct vhost_scsi_target t;
mutex_lock(&s->dev.mutex);
memcpy(t.vhost_wwpn, s->vs_vhost_wwpn, sizeof(t.vhost_wwpn));
mutex_unlock(&s->dev.mutex);
vhost_scsi_clear_endpoint(s, &t);
vhost_dev_stop(&s->dev);
vhost_dev_cleanup(&s->dev, false);
/* Jobs can re-queue themselves in evt kick handler. Do extra flush. */
vhost_scsi_flush(s);
kfree(s->dev.vqs);
kfree(s);
return 0;
}
static long vhost_scsi_ioctl(struct file *f, unsigned int ioctl,
unsigned long arg)
{
struct vhost_scsi *vs = f->private_data;
struct vhost_scsi_target backend;
void __user *argp = (void __user *)arg;
u64 __user *featurep = argp;
u32 __user *eventsp = argp;
u32 events_missed;
u64 features;
int r, abi_version = VHOST_SCSI_ABI_VERSION;
struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
switch (ioctl) {
case VHOST_SCSI_SET_ENDPOINT:
if (copy_from_user(&backend, argp, sizeof backend))
return -EFAULT;
if (backend.reserved != 0)
return -EOPNOTSUPP;
return vhost_scsi_set_endpoint(vs, &backend);
case VHOST_SCSI_CLEAR_ENDPOINT:
if (copy_from_user(&backend, argp, sizeof backend))
return -EFAULT;
if (backend.reserved != 0)
return -EOPNOTSUPP;
return vhost_scsi_clear_endpoint(vs, &backend);
case VHOST_SCSI_GET_ABI_VERSION:
if (copy_to_user(argp, &abi_version, sizeof abi_version))
return -EFAULT;
return 0;
case VHOST_SCSI_SET_EVENTS_MISSED:
if (get_user(events_missed, eventsp))
return -EFAULT;
mutex_lock(&vq->mutex);
vs->vs_events_missed = events_missed;
mutex_unlock(&vq->mutex);
return 0;
case VHOST_SCSI_GET_EVENTS_MISSED:
mutex_lock(&vq->mutex);
events_missed = vs->vs_events_missed;
mutex_unlock(&vq->mutex);
if (put_user(events_missed, eventsp))
return -EFAULT;
return 0;
case VHOST_GET_FEATURES:
features = VHOST_SCSI_FEATURES;
if (copy_to_user(featurep, &features, sizeof features))
return -EFAULT;
return 0;
case VHOST_SET_FEATURES:
if (copy_from_user(&features, featurep, sizeof features))
return -EFAULT;
return vhost_scsi_set_features(vs, features);
default:
mutex_lock(&vs->dev.mutex);
r = vhost_dev_ioctl(&vs->dev, ioctl, argp);
/* TODO: flush backend after dev ioctl. */
if (r == -ENOIOCTLCMD)
r = vhost_vring_ioctl(&vs->dev, ioctl, argp);
mutex_unlock(&vs->dev.mutex);
return r;
}
}
#ifdef CONFIG_COMPAT
static long vhost_scsi_compat_ioctl(struct file *f, unsigned int ioctl,
unsigned long arg)
{
return vhost_scsi_ioctl(f, ioctl, (unsigned long)compat_ptr(arg));
}
#endif
static const struct file_operations vhost_scsi_fops = {
.owner = THIS_MODULE,
.release = vhost_scsi_release,
.unlocked_ioctl = vhost_scsi_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = vhost_scsi_compat_ioctl,
#endif
.open = vhost_scsi_open,
.llseek = noop_llseek,
};
static struct miscdevice vhost_scsi_misc = {
MISC_DYNAMIC_MINOR,
"vhost-scsi",
&vhost_scsi_fops,
};
static int __init vhost_scsi_register(void)
{
return misc_register(&vhost_scsi_misc);
}
static int vhost_scsi_deregister(void)
{
return misc_deregister(&vhost_scsi_misc);
}
static char *tcm_vhost_dump_proto_id(struct tcm_vhost_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 void tcm_vhost_do_plug(struct tcm_vhost_tpg *tpg,
struct se_lun *lun, bool plug)
{
struct vhost_scsi *vs = tpg->vhost_scsi;
struct vhost_virtqueue *vq;
u32 reason;
if (!vs)
return;
mutex_lock(&vs->dev.mutex);
if (!vhost_has_feature(&vs->dev, VIRTIO_SCSI_F_HOTPLUG)) {
mutex_unlock(&vs->dev.mutex);
return;
}
if (plug)
reason = VIRTIO_SCSI_EVT_RESET_RESCAN;
else
reason = VIRTIO_SCSI_EVT_RESET_REMOVED;
vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
mutex_lock(&vq->mutex);
tcm_vhost_send_evt(vs, tpg, lun,
VIRTIO_SCSI_T_TRANSPORT_RESET, reason);
mutex_unlock(&vq->mutex);
mutex_unlock(&vs->dev.mutex);
}
static void tcm_vhost_hotplug(struct tcm_vhost_tpg *tpg, struct se_lun *lun)
{
tcm_vhost_do_plug(tpg, lun, true);
}
static void tcm_vhost_hotunplug(struct tcm_vhost_tpg *tpg, struct se_lun *lun)
{
tcm_vhost_do_plug(tpg, lun, false);
}
static int tcm_vhost_port_link(struct se_portal_group *se_tpg,
struct se_lun *lun)
{
struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg,
struct tcm_vhost_tpg, se_tpg);
mutex_lock(&tcm_vhost_mutex);
mutex_lock(&tv_tpg->tv_tpg_mutex);
tv_tpg->tv_tpg_port_count++;
mutex_unlock(&tv_tpg->tv_tpg_mutex);
tcm_vhost_hotplug(tv_tpg, lun);
mutex_unlock(&tcm_vhost_mutex);
return 0;
}
static void tcm_vhost_port_unlink(struct se_portal_group *se_tpg,
struct se_lun *lun)
{
struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg,
struct tcm_vhost_tpg, se_tpg);
mutex_lock(&tcm_vhost_mutex);
mutex_lock(&tv_tpg->tv_tpg_mutex);
tv_tpg->tv_tpg_port_count--;
mutex_unlock(&tv_tpg->tv_tpg_mutex);
tcm_vhost_hotunplug(tv_tpg, lun);
mutex_unlock(&tcm_vhost_mutex);
}
static struct se_node_acl *tcm_vhost_make_nodeacl(
struct se_portal_group *se_tpg,
struct config_group *group,
const char *name)
{
struct se_node_acl *se_nacl, *se_nacl_new;
struct tcm_vhost_nacl *nacl;
u64 wwpn = 0;
u32 nexus_depth;
/* tcm_vhost_parse_wwn(name, &wwpn, 1) < 0)
return ERR_PTR(-EINVAL); */
se_nacl_new = tcm_vhost_alloc_fabric_acl(se_tpg);
if (!se_nacl_new)
return ERR_PTR(-ENOMEM);
nexus_depth = 1;
/*
* se_nacl_new may be released by core_tpg_add_initiator_node_acl()
* when converting a NodeACL from demo mode -> explict
*/
se_nacl = core_tpg_add_initiator_node_acl(se_tpg, se_nacl_new,
name, nexus_depth);
if (IS_ERR(se_nacl)) {
tcm_vhost_release_fabric_acl(se_tpg, se_nacl_new);
return se_nacl;
}
/*
* Locate our struct tcm_vhost_nacl and set the FC Nport WWPN
*/
nacl = container_of(se_nacl, struct tcm_vhost_nacl, se_node_acl);
nacl->iport_wwpn = wwpn;
return se_nacl;
}
static void tcm_vhost_drop_nodeacl(struct se_node_acl *se_acl)
{
struct tcm_vhost_nacl *nacl = container_of(se_acl,
struct tcm_vhost_nacl, se_node_acl);
core_tpg_del_initiator_node_acl(se_acl->se_tpg, se_acl, 1);
kfree(nacl);
}
static int tcm_vhost_make_nexus(struct tcm_vhost_tpg *tv_tpg,
const char *name)
{
struct se_portal_group *se_tpg;
struct tcm_vhost_nexus *tv_nexus;
mutex_lock(&tv_tpg->tv_tpg_mutex);
if (tv_tpg->tpg_nexus) {
mutex_unlock(&tv_tpg->tv_tpg_mutex);
pr_debug("tv_tpg->tpg_nexus already exists\n");
return -EEXIST;
}
se_tpg = &tv_tpg->se_tpg;
tv_nexus = kzalloc(sizeof(struct tcm_vhost_nexus), GFP_KERNEL);
if (!tv_nexus) {
mutex_unlock(&tv_tpg->tv_tpg_mutex);
pr_err("Unable to allocate struct tcm_vhost_nexus\n");
return -ENOMEM;
}
/*
* Initialize the struct se_session pointer
*/
tv_nexus->tvn_se_sess = transport_init_session();
if (IS_ERR(tv_nexus->tvn_se_sess)) {
mutex_unlock(&tv_tpg->tv_tpg_mutex);
kfree(tv_nexus);
return -ENOMEM;
}
/*
* Since we are running in 'demo mode' this call with generate a
* struct se_node_acl for the tcm_vhost 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(&tv_tpg->tv_tpg_mutex);
pr_debug("core_tpg_check_initiator_node_acl() failed"
" for %s\n", name);
transport_free_session(tv_nexus->tvn_se_sess);
kfree(tv_nexus);
return -ENOMEM;
}
/*
* Now register the TCM vhost virtual I_T Nexus as active with the
* call to __transport_register_session()
*/
__transport_register_session(se_tpg, tv_nexus->tvn_se_sess->se_node_acl,
tv_nexus->tvn_se_sess, tv_nexus);
tv_tpg->tpg_nexus = tv_nexus;
mutex_unlock(&tv_tpg->tv_tpg_mutex);
return 0;
}
static int tcm_vhost_drop_nexus(struct tcm_vhost_tpg *tpg)
{
struct se_session *se_sess;
struct tcm_vhost_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 TCM_vhost I_T Nexus with"
" active TPG port count: %d\n",
tpg->tv_tpg_port_count);
return -EBUSY;
}
if (tpg->tv_tpg_vhost_count != 0) {
mutex_unlock(&tpg->tv_tpg_mutex);
pr_err("Unable to remove TCM_vhost I_T Nexus with"
" active TPG vhost count: %d\n",
tpg->tv_tpg_vhost_count);
return -EBUSY;
}
pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated"
" %s Initiator Port: %s\n", tcm_vhost_dump_proto_id(tpg->tport),
tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
/*
* Release the SCSI I_T Nexus to the emulated vhost Target Port
*/
transport_deregister_session(tv_nexus->tvn_se_sess);
tpg->tpg_nexus = NULL;
mutex_unlock(&tpg->tv_tpg_mutex);
kfree(tv_nexus);
return 0;
}
static ssize_t tcm_vhost_tpg_show_nexus(struct se_portal_group *se_tpg,
char *page)
{
struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg,
struct tcm_vhost_tpg, se_tpg);
struct tcm_vhost_nexus *tv_nexus;
ssize_t ret;
mutex_lock(&tv_tpg->tv_tpg_mutex);
tv_nexus = tv_tpg->tpg_nexus;
if (!tv_nexus) {
mutex_unlock(&tv_tpg->tv_tpg_mutex);
return -ENODEV;
}
ret = snprintf(page, PAGE_SIZE, "%s\n",
tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
mutex_unlock(&tv_tpg->tv_tpg_mutex);
return ret;
}
static ssize_t tcm_vhost_tpg_store_nexus(struct se_portal_group *se_tpg,
const char *page,
size_t count)
{
struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg,
struct tcm_vhost_tpg, se_tpg);
struct tcm_vhost_tport *tport_wwn = tv_tpg->tport;
unsigned char i_port[TCM_VHOST_NAMELEN], *ptr, *port_ptr;
int ret;
/*
* Shutdown the active I_T nexus if 'NULL' is passed..
*/
if (!strncmp(page, "NULL", 4)) {
ret = tcm_vhost_drop_nexus(tv_tpg);
return (!ret) ? count : ret;
}
/*
* Otherwise make sure the passed virtual Initiator port WWN matches
* the fabric protocol_id set in tcm_vhost_make_tport(), and call
* tcm_vhost_make_nexus().
*/
if (strlen(page) >= TCM_VHOST_NAMELEN) {
pr_err("Emulated NAA Sas Address: %s, exceeds"
" max: %d\n", page, TCM_VHOST_NAMELEN);
return -EINVAL;
}
snprintf(&i_port[0], TCM_VHOST_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,
tcm_vhost_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,
tcm_vhost_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,
tcm_vhost_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 = tcm_vhost_make_nexus(tv_tpg, port_ptr);
if (ret < 0)
return ret;
return count;
}
TF_TPG_BASE_ATTR(tcm_vhost, nexus, S_IRUGO | S_IWUSR);
static struct configfs_attribute *tcm_vhost_tpg_attrs[] = {
&tcm_vhost_tpg_nexus.attr,
NULL,
};
static struct se_portal_group *tcm_vhost_make_tpg(struct se_wwn *wwn,
struct config_group *group,
const char *name)
{
struct tcm_vhost_tport *tport = container_of(wwn,
struct tcm_vhost_tport, tport_wwn);
struct tcm_vhost_tpg *tpg;
unsigned long tpgt;
int ret;
if (strstr(name, "tpgt_") != name)
return ERR_PTR(-EINVAL);
if (kstrtoul(name + 5, 10, &tpgt) || tpgt > UINT_MAX)
return ERR_PTR(-EINVAL);
tpg = kzalloc(sizeof(struct tcm_vhost_tpg), GFP_KERNEL);
if (!tpg) {
pr_err("Unable to allocate struct tcm_vhost_tpg");
return ERR_PTR(-ENOMEM);
}
mutex_init(&tpg->tv_tpg_mutex);
INIT_LIST_HEAD(&tpg->tv_tpg_list);
tpg->tport = tport;
tpg->tport_tpgt = tpgt;
ret = core_tpg_register(&tcm_vhost_fabric_configfs->tf_ops, wwn,
&tpg->se_tpg, tpg, TRANSPORT_TPG_TYPE_NORMAL);
if (ret < 0) {
kfree(tpg);
return NULL;
}
mutex_lock(&tcm_vhost_mutex);
list_add_tail(&tpg->tv_tpg_list, &tcm_vhost_list);
mutex_unlock(&tcm_vhost_mutex);
return &tpg->se_tpg;
}
static void tcm_vhost_drop_tpg(struct se_portal_group *se_tpg)
{
struct tcm_vhost_tpg *tpg = container_of(se_tpg,
struct tcm_vhost_tpg, se_tpg);
mutex_lock(&tcm_vhost_mutex);
list_del(&tpg->tv_tpg_list);
mutex_unlock(&tcm_vhost_mutex);
/*
* Release the virtual I_T Nexus for this vhost TPG
*/
tcm_vhost_drop_nexus(tpg);
/*
* Deregister the se_tpg from TCM..
*/
core_tpg_deregister(se_tpg);
kfree(tpg);
}
static struct se_wwn *tcm_vhost_make_tport(struct target_fabric_configfs *tf,
struct config_group *group,
const char *name)
{
struct tcm_vhost_tport *tport;
char *ptr;
u64 wwpn = 0;
int off = 0;
/* if (tcm_vhost_parse_wwn(name, &wwpn, 1) < 0)
return ERR_PTR(-EINVAL); */
tport = kzalloc(sizeof(struct tcm_vhost_tport), GFP_KERNEL);
if (!tport) {
pr_err("Unable to allocate struct tcm_vhost_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) >= TCM_VHOST_NAMELEN) {
pr_err("Emulated %s Address: %s, exceeds"
" max: %d\n", name, tcm_vhost_dump_proto_id(tport),
TCM_VHOST_NAMELEN);
kfree(tport);
return ERR_PTR(-EINVAL);
}
snprintf(&tport->tport_name[0], TCM_VHOST_NAMELEN, "%s", &name[off]);
pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target"
" %s Address: %s\n", tcm_vhost_dump_proto_id(tport), name);
return &tport->tport_wwn;
}
static void tcm_vhost_drop_tport(struct se_wwn *wwn)
{
struct tcm_vhost_tport *tport = container_of(wwn,
struct tcm_vhost_tport, tport_wwn);
pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target"
" %s Address: %s\n", tcm_vhost_dump_proto_id(tport),
tport->tport_name);
kfree(tport);
}
static ssize_t tcm_vhost_wwn_show_attr_version(
struct target_fabric_configfs *tf,
char *page)
{
return sprintf(page, "TCM_VHOST fabric module %s on %s/%s"
"on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname,
utsname()->machine);
}
TF_WWN_ATTR_RO(tcm_vhost, version);
static struct configfs_attribute *tcm_vhost_wwn_attrs[] = {
&tcm_vhost_wwn_version.attr,
NULL,
};
static struct target_core_fabric_ops tcm_vhost_ops = {
.get_fabric_name = tcm_vhost_get_fabric_name,
.get_fabric_proto_ident = tcm_vhost_get_fabric_proto_ident,
.tpg_get_wwn = tcm_vhost_get_fabric_wwn,
.tpg_get_tag = tcm_vhost_get_tag,
.tpg_get_default_depth = tcm_vhost_get_default_depth,
.tpg_get_pr_transport_id = tcm_vhost_get_pr_transport_id,
.tpg_get_pr_transport_id_len = tcm_vhost_get_pr_transport_id_len,
.tpg_parse_pr_out_transport_id = tcm_vhost_parse_pr_out_transport_id,
.tpg_check_demo_mode = tcm_vhost_check_true,
.tpg_check_demo_mode_cache = tcm_vhost_check_true,
.tpg_check_demo_mode_write_protect = tcm_vhost_check_false,
.tpg_check_prod_mode_write_protect = tcm_vhost_check_false,
.tpg_alloc_fabric_acl = tcm_vhost_alloc_fabric_acl,
.tpg_release_fabric_acl = tcm_vhost_release_fabric_acl,
.tpg_get_inst_index = tcm_vhost_tpg_get_inst_index,
.release_cmd = tcm_vhost_release_cmd,
.shutdown_session = tcm_vhost_shutdown_session,
.close_session = tcm_vhost_close_session,
.sess_get_index = tcm_vhost_sess_get_index,
.sess_get_initiator_sid = NULL,
.write_pending = tcm_vhost_write_pending,
.write_pending_status = tcm_vhost_write_pending_status,
.set_default_node_attributes = tcm_vhost_set_default_node_attrs,
.get_task_tag = tcm_vhost_get_task_tag,
.get_cmd_state = tcm_vhost_get_cmd_state,
.queue_data_in = tcm_vhost_queue_data_in,
.queue_status = tcm_vhost_queue_status,
.queue_tm_rsp = tcm_vhost_queue_tm_rsp,
/*
* Setup callers for generic logic in target_core_fabric_configfs.c
*/
.fabric_make_wwn = tcm_vhost_make_tport,
.fabric_drop_wwn = tcm_vhost_drop_tport,
.fabric_make_tpg = tcm_vhost_make_tpg,
.fabric_drop_tpg = tcm_vhost_drop_tpg,
.fabric_post_link = tcm_vhost_port_link,
.fabric_pre_unlink = tcm_vhost_port_unlink,
.fabric_make_np = NULL,
.fabric_drop_np = NULL,
.fabric_make_nodeacl = tcm_vhost_make_nodeacl,
.fabric_drop_nodeacl = tcm_vhost_drop_nodeacl,
};
static int tcm_vhost_register_configfs(void)
{
struct target_fabric_configfs *fabric;
int ret;
pr_debug("TCM_VHOST fabric module %s on %s/%s"
" on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname,
utsname()->machine);
/*
* Register the top level struct config_item_type with TCM core
*/
fabric = target_fabric_configfs_init(THIS_MODULE, "vhost");
if (IS_ERR(fabric)) {
pr_err("target_fabric_configfs_init() failed\n");
return PTR_ERR(fabric);
}
/*
* Setup fabric->tf_ops from our local tcm_vhost_ops
*/
fabric->tf_ops = tcm_vhost_ops;
/*
* Setup default attribute lists for various fabric->tf_cit_tmpl
*/
TF_CIT_TMPL(fabric)->tfc_wwn_cit.ct_attrs = tcm_vhost_wwn_attrs;
TF_CIT_TMPL(fabric)->tfc_tpg_base_cit.ct_attrs = tcm_vhost_tpg_attrs;
TF_CIT_TMPL(fabric)->tfc_tpg_attrib_cit.ct_attrs = NULL;
TF_CIT_TMPL(fabric)->tfc_tpg_param_cit.ct_attrs = NULL;
TF_CIT_TMPL(fabric)->tfc_tpg_np_base_cit.ct_attrs = NULL;
TF_CIT_TMPL(fabric)->tfc_tpg_nacl_base_cit.ct_attrs = NULL;
TF_CIT_TMPL(fabric)->tfc_tpg_nacl_attrib_cit.ct_attrs = NULL;
TF_CIT_TMPL(fabric)->tfc_tpg_nacl_auth_cit.ct_attrs = NULL;
TF_CIT_TMPL(fabric)->tfc_tpg_nacl_param_cit.ct_attrs = NULL;
/*
* Register the fabric for use within TCM
*/
ret = target_fabric_configfs_register(fabric);
if (ret < 0) {
pr_err("target_fabric_configfs_register() failed"
" for TCM_VHOST\n");
return ret;
}
/*
* Setup our local pointer to *fabric
*/
tcm_vhost_fabric_configfs = fabric;
pr_debug("TCM_VHOST[0] - Set fabric -> tcm_vhost_fabric_configfs\n");
return 0;
};
static void tcm_vhost_deregister_configfs(void)
{
if (!tcm_vhost_fabric_configfs)
return;
target_fabric_configfs_deregister(tcm_vhost_fabric_configfs);
tcm_vhost_fabric_configfs = NULL;
pr_debug("TCM_VHOST[0] - Cleared tcm_vhost_fabric_configfs\n");
};
static int __init tcm_vhost_init(void)
{
int ret = -ENOMEM;
/*
* Use our own dedicated workqueue for submitting I/O into
* target core to avoid contention within system_wq.
*/
tcm_vhost_workqueue = alloc_workqueue("tcm_vhost", 0, 0);
if (!tcm_vhost_workqueue)
goto out;
ret = vhost_scsi_register();
if (ret < 0)
goto out_destroy_workqueue;
ret = tcm_vhost_register_configfs();
if (ret < 0)
goto out_vhost_scsi_deregister;
return 0;
out_vhost_scsi_deregister:
vhost_scsi_deregister();
out_destroy_workqueue:
destroy_workqueue(tcm_vhost_workqueue);
out:
return ret;
};
static void tcm_vhost_exit(void)
{
tcm_vhost_deregister_configfs();
vhost_scsi_deregister();
destroy_workqueue(tcm_vhost_workqueue);
};
MODULE_DESCRIPTION("VHOST_SCSI series fabric driver");
MODULE_ALIAS("tcm_vhost");
MODULE_LICENSE("GPL");
module_init(tcm_vhost_init);
module_exit(tcm_vhost_exit);