linux-stable/drivers/vhost/scsi.c
Sudhakar Panneerselvam 5ae6a6a915 scsi: vhost: Notify TCM about the maximum sg entries supported per command
vhost-scsi pre-allocates the maximum sg entries per command and if a
command requires more than VHOST_SCSI_PREALLOC_SGLS entries, then that
command is failed by it. This patch lets vhost communicate the max sg limit
when it registers vhost_scsi_ops with TCM. With this change, TCM would
report the max sg entries through "Block Limits" VPD page which will be
typically queried by the SCSI initiator during device discovery. By knowing
this limit, the initiator could ensure the maximum transfer length is less
than or equal to what is reported by vhost-scsi.

Link: https://lore.kernel.org/r/1590166317-953-1-git-send-email-sudhakar.panneerselvam@oracle.com
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Sudhakar Panneerselvam <sudhakar.panneerselvam@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-26 15:52:08 -04:00

2363 lines
61 KiB
C

/*******************************************************************************
* Vhost kernel TCM fabric driver for virtio SCSI initiators
*
* (C) Copyright 2010-2013 Datera, Inc.
* (C) Copyright 2010-2012 IBM Corp.
*
* Licensed to the Linux Foundation under the General Public License (GPL) version 2.
*
* Authors: Nicholas A. Bellinger <nab@daterainc.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/vmalloc.h>
#include <linux/miscdevice.h>
#include <asm/unaligned.h>
#include <scsi/scsi_common.h>
#include <scsi/scsi_proto.h>
#include <target/target_core_base.h>
#include <target/target_core_fabric.h>
#include <linux/vhost.h>
#include <linux/virtio_scsi.h>
#include <linux/llist.h>
#include <linux/bitmap.h>
#include "vhost.h"
#define VHOST_SCSI_VERSION "v0.1"
#define VHOST_SCSI_NAMELEN 256
#define VHOST_SCSI_MAX_CDB_SIZE 32
#define VHOST_SCSI_DEFAULT_TAGS 256
#define VHOST_SCSI_PREALLOC_SGLS 2048
#define VHOST_SCSI_PREALLOC_UPAGES 2048
#define VHOST_SCSI_PREALLOC_PROT_SGLS 2048
/* Max number of requests before requeueing the job.
* Using this limit prevents one virtqueue from starving others with
* request.
*/
#define VHOST_SCSI_WEIGHT 256
struct vhost_scsi_inflight {
/* Wait for the flush operation to finish */
struct completion comp;
/* Refcount for the inflight reqs */
struct kref kref;
};
struct vhost_scsi_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 response incoming iovecs */
int tvc_in_iovs;
/* 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;
u32 tvc_prot_sgl_count;
/* Saved unpacked SCSI LUN for vhost_scsi_submission_work() */
u32 tvc_lun;
/* Pointer to the SGL formatted memory from virtio-scsi */
struct scatterlist *tvc_sgl;
struct scatterlist *tvc_prot_sgl;
struct page **tvc_upages;
/* Pointer to response header iovec */
struct iovec tvc_resp_iov;
/* 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 vhost_scsi_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 vhost_scsi_submission_work() */
struct work_struct work;
/* Copy of the incoming SCSI command descriptor block (CDB) */
unsigned char tvc_cdb[VHOST_SCSI_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 vhost_scsi_nexus {
/* Pointer to TCM session for I_T Nexus */
struct se_session *tvn_se_sess;
};
struct vhost_scsi_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;
/* Used for enabling T10-PI with legacy devices */
int tv_fabric_prot_type;
/* list for vhost_scsi_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 vhost_scsi_nexus *tpg_nexus;
/* Pointer back to vhost_scsi_tport */
struct vhost_scsi_tport *tport;
/* Returned by vhost_scsi_make_tpg() */
struct se_portal_group se_tpg;
/* Pointer back to vhost_scsi, protected by tv_tpg_mutex */
struct vhost_scsi *vhost_scsi;
};
struct vhost_scsi_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[VHOST_SCSI_NAMELEN];
/* Returned by vhost_scsi_make_tport() */
struct se_wwn tport_wwn;
};
struct vhost_scsi_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,
};
/* Note: can't set VIRTIO_F_VERSION_1 yet, since that implies ANY_LAYOUT. */
enum {
VHOST_SCSI_FEATURES = VHOST_FEATURES | (1ULL << VIRTIO_SCSI_F_HOTPLUG) |
(1ULL << VIRTIO_SCSI_F_T10_PI)
};
#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 vhost_scsi_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 */
};
/*
* Context for processing request and control queue operations.
*/
struct vhost_scsi_ctx {
int head;
unsigned int out, in;
size_t req_size, rsp_size;
size_t out_size, in_size;
u8 *target, *lunp;
void *req;
struct iov_iter out_iter;
};
static struct workqueue_struct *vhost_scsi_workqueue;
/* Global spinlock to protect vhost_scsi TPG list for vhost IOCTL access */
static DEFINE_MUTEX(vhost_scsi_mutex);
static LIST_HEAD(vhost_scsi_list);
static void vhost_scsi_done_inflight(struct kref *kref)
{
struct vhost_scsi_inflight *inflight;
inflight = container_of(kref, struct vhost_scsi_inflight, kref);
complete(&inflight->comp);
}
static void vhost_scsi_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 *
vhost_scsi_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 vhost_scsi_put_inflight(struct vhost_scsi_inflight *inflight)
{
kref_put(&inflight->kref, vhost_scsi_done_inflight);
}
static int vhost_scsi_check_true(struct se_portal_group *se_tpg)
{
return 1;
}
static int vhost_scsi_check_false(struct se_portal_group *se_tpg)
{
return 0;
}
static char *vhost_scsi_get_fabric_wwn(struct se_portal_group *se_tpg)
{
struct vhost_scsi_tpg *tpg = container_of(se_tpg,
struct vhost_scsi_tpg, se_tpg);
struct vhost_scsi_tport *tport = tpg->tport;
return &tport->tport_name[0];
}
static u16 vhost_scsi_get_tpgt(struct se_portal_group *se_tpg)
{
struct vhost_scsi_tpg *tpg = container_of(se_tpg,
struct vhost_scsi_tpg, se_tpg);
return tpg->tport_tpgt;
}
static int vhost_scsi_check_prot_fabric_only(struct se_portal_group *se_tpg)
{
struct vhost_scsi_tpg *tpg = container_of(se_tpg,
struct vhost_scsi_tpg, se_tpg);
return tpg->tv_fabric_prot_type;
}
static u32 vhost_scsi_tpg_get_inst_index(struct se_portal_group *se_tpg)
{
return 1;
}
static void vhost_scsi_release_cmd(struct se_cmd *se_cmd)
{
struct vhost_scsi_cmd *tv_cmd = container_of(se_cmd,
struct vhost_scsi_cmd, tvc_se_cmd);
struct se_session *se_sess = tv_cmd->tvc_nexus->tvn_se_sess;
int i;
if (tv_cmd->tvc_sgl_count) {
for (i = 0; i < tv_cmd->tvc_sgl_count; i++)
put_page(sg_page(&tv_cmd->tvc_sgl[i]));
}
if (tv_cmd->tvc_prot_sgl_count) {
for (i = 0; i < tv_cmd->tvc_prot_sgl_count; i++)
put_page(sg_page(&tv_cmd->tvc_prot_sgl[i]));
}
vhost_scsi_put_inflight(tv_cmd->inflight);
target_free_tag(se_sess, se_cmd);
}
static u32 vhost_scsi_sess_get_index(struct se_session *se_sess)
{
return 0;
}
static int vhost_scsi_write_pending(struct se_cmd *se_cmd)
{
/* Go ahead and process the write immediately */
target_execute_cmd(se_cmd);
return 0;
}
static void vhost_scsi_set_default_node_attrs(struct se_node_acl *nacl)
{
return;
}
static int vhost_scsi_get_cmd_state(struct se_cmd *se_cmd)
{
return 0;
}
static void vhost_scsi_complete_cmd(struct vhost_scsi_cmd *cmd)
{
struct vhost_scsi *vs = cmd->tvc_vhost;
llist_add(&cmd->tvc_completion_list, &vs->vs_completion_list);
vhost_work_queue(&vs->dev, &vs->vs_completion_work);
}
static int vhost_scsi_queue_data_in(struct se_cmd *se_cmd)
{
struct vhost_scsi_cmd *cmd = container_of(se_cmd,
struct vhost_scsi_cmd, tvc_se_cmd);
vhost_scsi_complete_cmd(cmd);
return 0;
}
static int vhost_scsi_queue_status(struct se_cmd *se_cmd)
{
struct vhost_scsi_cmd *cmd = container_of(se_cmd,
struct vhost_scsi_cmd, tvc_se_cmd);
vhost_scsi_complete_cmd(cmd);
return 0;
}
static void vhost_scsi_queue_tm_rsp(struct se_cmd *se_cmd)
{
return;
}
static void vhost_scsi_aborted_task(struct se_cmd *se_cmd)
{
return;
}
static void vhost_scsi_free_evt(struct vhost_scsi *vs, struct vhost_scsi_evt *evt)
{
vs->vs_events_nr--;
kfree(evt);
}
static struct vhost_scsi_evt *
vhost_scsi_allocate_evt(struct vhost_scsi *vs,
u32 event, u32 reason)
{
struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
struct vhost_scsi_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 vhost_scsi_evt\n");
vs->vs_events_missed = true;
return NULL;
}
evt->event.event = cpu_to_vhost32(vq, event);
evt->event.reason = cpu_to_vhost32(vq, reason);
vs->vs_events_nr++;
return evt;
}
static void vhost_scsi_free_cmd(struct vhost_scsi_cmd *cmd)
{
struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
/* TODO locking against target/backend threads? */
transport_generic_free_cmd(se_cmd, 0);
}
static int vhost_scsi_check_stop_free(struct se_cmd *se_cmd)
{
return target_put_sess_cmd(se_cmd);
}
static void
vhost_scsi_do_evt_work(struct vhost_scsi *vs, struct vhost_scsi_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(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 |= cpu_to_vhost32(vq, 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 vhost_scsi_send_event\n");
}
static void vhost_scsi_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 vhost_scsi_evt *evt, *t;
struct llist_node *llnode;
mutex_lock(&vq->mutex);
llnode = llist_del_all(&vs->vs_event_list);
llist_for_each_entry_safe(evt, t, llnode, list) {
vhost_scsi_do_evt_work(vs, evt);
vhost_scsi_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 vhost_scsi_cmd *cmd, *t;
struct llist_node *llnode;
struct se_cmd *se_cmd;
struct iov_iter iov_iter;
int ret, vq;
bitmap_zero(signal, VHOST_SCSI_MAX_VQ);
llnode = llist_del_all(&vs->vs_completion_list);
llist_for_each_entry_safe(cmd, t, llnode, tvc_completion_list) {
se_cmd = &cmd->tvc_se_cmd;
pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__,
cmd, se_cmd->residual_count, se_cmd->scsi_status);
memset(&v_rsp, 0, sizeof(v_rsp));
v_rsp.resid = cpu_to_vhost32(cmd->tvc_vq, se_cmd->residual_count);
/* TODO is status_qualifier field needed? */
v_rsp.status = se_cmd->scsi_status;
v_rsp.sense_len = cpu_to_vhost32(cmd->tvc_vq,
se_cmd->scsi_sense_length);
memcpy(v_rsp.sense, cmd->tvc_sense_buf,
se_cmd->scsi_sense_length);
iov_iter_init(&iov_iter, READ, &cmd->tvc_resp_iov,
cmd->tvc_in_iovs, sizeof(v_rsp));
ret = copy_to_iter(&v_rsp, sizeof(v_rsp), &iov_iter);
if (likely(ret == sizeof(v_rsp))) {
struct vhost_scsi_virtqueue *q;
vhost_add_used(cmd->tvc_vq, cmd->tvc_vq_desc, 0);
q = container_of(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(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 vhost_scsi_cmd *
vhost_scsi_get_tag(struct vhost_virtqueue *vq, struct vhost_scsi_tpg *tpg,
unsigned char *cdb, u64 scsi_tag, u16 lun, u8 task_attr,
u32 exp_data_len, int data_direction)
{
struct vhost_scsi_cmd *cmd;
struct vhost_scsi_nexus *tv_nexus;
struct se_session *se_sess;
struct scatterlist *sg, *prot_sg;
struct page **pages;
int tag, cpu;
tv_nexus = tpg->tpg_nexus;
if (!tv_nexus) {
pr_err("Unable to locate active struct vhost_scsi_nexus\n");
return ERR_PTR(-EIO);
}
se_sess = tv_nexus->tvn_se_sess;
tag = sbitmap_queue_get(&se_sess->sess_tag_pool, &cpu);
if (tag < 0) {
pr_err("Unable to obtain tag for vhost_scsi_cmd\n");
return ERR_PTR(-ENOMEM);
}
cmd = &((struct vhost_scsi_cmd *)se_sess->sess_cmd_map)[tag];
sg = cmd->tvc_sgl;
prot_sg = cmd->tvc_prot_sgl;
pages = cmd->tvc_upages;
memset(cmd, 0, sizeof(*cmd));
cmd->tvc_sgl = sg;
cmd->tvc_prot_sgl = prot_sg;
cmd->tvc_upages = pages;
cmd->tvc_se_cmd.map_tag = tag;
cmd->tvc_se_cmd.map_cpu = cpu;
cmd->tvc_tag = scsi_tag;
cmd->tvc_lun = lun;
cmd->tvc_task_attr = task_attr;
cmd->tvc_exp_data_len = exp_data_len;
cmd->tvc_data_direction = data_direction;
cmd->tvc_nexus = tv_nexus;
cmd->inflight = vhost_scsi_get_inflight(vq);
memcpy(cmd->tvc_cdb, cdb, VHOST_SCSI_MAX_CDB_SIZE);
return 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 vhost_scsi_cmd *cmd,
struct iov_iter *iter,
struct scatterlist *sgl,
bool write)
{
struct page **pages = cmd->tvc_upages;
struct scatterlist *sg = sgl;
ssize_t bytes;
size_t offset;
unsigned int npages = 0;
bytes = iov_iter_get_pages(iter, pages, LONG_MAX,
VHOST_SCSI_PREALLOC_UPAGES, &offset);
/* No pages were pinned */
if (bytes <= 0)
return bytes < 0 ? bytes : -EFAULT;
iov_iter_advance(iter, bytes);
while (bytes) {
unsigned n = min_t(unsigned, PAGE_SIZE - offset, bytes);
sg_set_page(sg++, pages[npages++], n, offset);
bytes -= n;
offset = 0;
}
return npages;
}
static int
vhost_scsi_calc_sgls(struct iov_iter *iter, size_t bytes, int max_sgls)
{
int sgl_count = 0;
if (!iter || !iter->iov) {
pr_err("%s: iter->iov is NULL, but expected bytes: %zu"
" present\n", __func__, bytes);
return -EINVAL;
}
sgl_count = iov_iter_npages(iter, 0xffff);
if (sgl_count > max_sgls) {
pr_err("%s: requested sgl_count: %d exceeds pre-allocated"
" max_sgls: %d\n", __func__, sgl_count, max_sgls);
return -EINVAL;
}
return sgl_count;
}
static int
vhost_scsi_iov_to_sgl(struct vhost_scsi_cmd *cmd, bool write,
struct iov_iter *iter,
struct scatterlist *sg, int sg_count)
{
struct scatterlist *p = sg;
int ret;
while (iov_iter_count(iter)) {
ret = vhost_scsi_map_to_sgl(cmd, iter, sg, write);
if (ret < 0) {
while (p < sg) {
struct page *page = sg_page(p++);
if (page)
put_page(page);
}
return ret;
}
sg += ret;
}
return 0;
}
static int
vhost_scsi_mapal(struct vhost_scsi_cmd *cmd,
size_t prot_bytes, struct iov_iter *prot_iter,
size_t data_bytes, struct iov_iter *data_iter)
{
int sgl_count, ret;
bool write = (cmd->tvc_data_direction == DMA_FROM_DEVICE);
if (prot_bytes) {
sgl_count = vhost_scsi_calc_sgls(prot_iter, prot_bytes,
VHOST_SCSI_PREALLOC_PROT_SGLS);
if (sgl_count < 0)
return sgl_count;
sg_init_table(cmd->tvc_prot_sgl, sgl_count);
cmd->tvc_prot_sgl_count = sgl_count;
pr_debug("%s prot_sg %p prot_sgl_count %u\n", __func__,
cmd->tvc_prot_sgl, cmd->tvc_prot_sgl_count);
ret = vhost_scsi_iov_to_sgl(cmd, write, prot_iter,
cmd->tvc_prot_sgl,
cmd->tvc_prot_sgl_count);
if (ret < 0) {
cmd->tvc_prot_sgl_count = 0;
return ret;
}
}
sgl_count = vhost_scsi_calc_sgls(data_iter, data_bytes,
VHOST_SCSI_PREALLOC_SGLS);
if (sgl_count < 0)
return sgl_count;
sg_init_table(cmd->tvc_sgl, sgl_count);
cmd->tvc_sgl_count = sgl_count;
pr_debug("%s data_sg %p data_sgl_count %u\n", __func__,
cmd->tvc_sgl, cmd->tvc_sgl_count);
ret = vhost_scsi_iov_to_sgl(cmd, write, data_iter,
cmd->tvc_sgl, cmd->tvc_sgl_count);
if (ret < 0) {
cmd->tvc_sgl_count = 0;
return ret;
}
return 0;
}
static int vhost_scsi_to_tcm_attr(int attr)
{
switch (attr) {
case VIRTIO_SCSI_S_SIMPLE:
return TCM_SIMPLE_TAG;
case VIRTIO_SCSI_S_ORDERED:
return TCM_ORDERED_TAG;
case VIRTIO_SCSI_S_HEAD:
return TCM_HEAD_TAG;
case VIRTIO_SCSI_S_ACA:
return TCM_ACA_TAG;
default:
break;
}
return TCM_SIMPLE_TAG;
}
static void vhost_scsi_submission_work(struct work_struct *work)
{
struct vhost_scsi_cmd *cmd =
container_of(work, struct vhost_scsi_cmd, work);
struct vhost_scsi_nexus *tv_nexus;
struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
struct scatterlist *sg_ptr, *sg_prot_ptr = NULL;
int rc;
/* FIXME: BIDI operation */
if (cmd->tvc_sgl_count) {
sg_ptr = cmd->tvc_sgl;
if (cmd->tvc_prot_sgl_count)
sg_prot_ptr = cmd->tvc_prot_sgl;
else
se_cmd->prot_pto = true;
} else {
sg_ptr = NULL;
}
tv_nexus = cmd->tvc_nexus;
se_cmd->tag = 0;
rc = target_submit_cmd_map_sgls(se_cmd, tv_nexus->tvn_se_sess,
cmd->tvc_cdb, &cmd->tvc_sense_buf[0],
cmd->tvc_lun, cmd->tvc_exp_data_len,
vhost_scsi_to_tcm_attr(cmd->tvc_task_attr),
cmd->tvc_data_direction, TARGET_SCF_ACK_KREF,
sg_ptr, cmd->tvc_sgl_count, NULL, 0, sg_prot_ptr,
cmd->tvc_prot_sgl_count);
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 int
vhost_scsi_get_desc(struct vhost_scsi *vs, struct vhost_virtqueue *vq,
struct vhost_scsi_ctx *vc)
{
int ret = -ENXIO;
vc->head = vhost_get_vq_desc(vq, vq->iov,
ARRAY_SIZE(vq->iov), &vc->out, &vc->in,
NULL, NULL);
pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n",
vc->head, vc->out, vc->in);
/* On error, stop handling until the next kick. */
if (unlikely(vc->head < 0))
goto done;
/* Nothing new? Wait for eventfd to tell us they refilled. */
if (vc->head == vq->num) {
if (unlikely(vhost_enable_notify(&vs->dev, vq))) {
vhost_disable_notify(&vs->dev, vq);
ret = -EAGAIN;
}
goto done;
}
/*
* Get the size of request and response buffers.
* FIXME: Not correct for BIDI operation
*/
vc->out_size = iov_length(vq->iov, vc->out);
vc->in_size = iov_length(&vq->iov[vc->out], vc->in);
/*
* Copy over the virtio-scsi request header, which for a
* ANY_LAYOUT enabled guest may span multiple iovecs, or a
* single iovec may contain both the header + outgoing
* WRITE payloads.
*
* copy_from_iter() will advance out_iter, so that it will
* point at the start of the outgoing WRITE payload, if
* DMA_TO_DEVICE is set.
*/
iov_iter_init(&vc->out_iter, WRITE, vq->iov, vc->out, vc->out_size);
ret = 0;
done:
return ret;
}
static int
vhost_scsi_chk_size(struct vhost_virtqueue *vq, struct vhost_scsi_ctx *vc)
{
if (unlikely(vc->in_size < vc->rsp_size)) {
vq_err(vq,
"Response buf too small, need min %zu bytes got %zu",
vc->rsp_size, vc->in_size);
return -EINVAL;
} else if (unlikely(vc->out_size < vc->req_size)) {
vq_err(vq,
"Request buf too small, need min %zu bytes got %zu",
vc->req_size, vc->out_size);
return -EIO;
}
return 0;
}
static int
vhost_scsi_get_req(struct vhost_virtqueue *vq, struct vhost_scsi_ctx *vc,
struct vhost_scsi_tpg **tpgp)
{
int ret = -EIO;
if (unlikely(!copy_from_iter_full(vc->req, vc->req_size,
&vc->out_iter))) {
vq_err(vq, "Faulted on copy_from_iter_full\n");
} else if (unlikely(*vc->lunp != 1)) {
/* virtio-scsi spec requires byte 0 of the lun to be 1 */
vq_err(vq, "Illegal virtio-scsi lun: %u\n", *vc->lunp);
} else {
struct vhost_scsi_tpg **vs_tpg, *tpg;
vs_tpg = vq->private_data; /* validated at handler entry */
tpg = READ_ONCE(vs_tpg[*vc->target]);
if (unlikely(!tpg)) {
vq_err(vq, "Target 0x%x does not exist\n", *vc->target);
} else {
if (tpgp)
*tpgp = tpg;
ret = 0;
}
}
return ret;
}
static void
vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
{
struct vhost_scsi_tpg **vs_tpg, *tpg;
struct virtio_scsi_cmd_req v_req;
struct virtio_scsi_cmd_req_pi v_req_pi;
struct vhost_scsi_ctx vc;
struct vhost_scsi_cmd *cmd;
struct iov_iter in_iter, prot_iter, data_iter;
u64 tag;
u32 exp_data_len, data_direction;
int ret, prot_bytes, c = 0;
u16 lun;
u8 task_attr;
bool t10_pi = vhost_has_feature(vq, VIRTIO_SCSI_F_T10_PI);
void *cdb;
mutex_lock(&vq->mutex);
/*
* We can handle the vq only after the endpoint is setup by calling the
* VHOST_SCSI_SET_ENDPOINT ioctl.
*/
vs_tpg = vq->private_data;
if (!vs_tpg)
goto out;
memset(&vc, 0, sizeof(vc));
vc.rsp_size = sizeof(struct virtio_scsi_cmd_resp);
vhost_disable_notify(&vs->dev, vq);
do {
ret = vhost_scsi_get_desc(vs, vq, &vc);
if (ret)
goto err;
/*
* Setup pointers and values based upon different virtio-scsi
* request header if T10_PI is enabled in KVM guest.
*/
if (t10_pi) {
vc.req = &v_req_pi;
vc.req_size = sizeof(v_req_pi);
vc.lunp = &v_req_pi.lun[0];
vc.target = &v_req_pi.lun[1];
} else {
vc.req = &v_req;
vc.req_size = sizeof(v_req);
vc.lunp = &v_req.lun[0];
vc.target = &v_req.lun[1];
}
/*
* Validate the size of request and response buffers.
* Check for a sane response buffer so we can report
* early errors back to the guest.
*/
ret = vhost_scsi_chk_size(vq, &vc);
if (ret)
goto err;
ret = vhost_scsi_get_req(vq, &vc, &tpg);
if (ret)
goto err;
ret = -EIO; /* bad target on any error from here on */
/*
* Determine data_direction by calculating the total outgoing
* iovec sizes + incoming iovec sizes vs. virtio-scsi request +
* response headers respectively.
*
* For DMA_TO_DEVICE this is out_iter, which is already pointing
* to the right place.
*
* For DMA_FROM_DEVICE, the iovec will be just past the end
* of the virtio-scsi response header in either the same
* or immediately following iovec.
*
* Any associated T10_PI bytes for the outgoing / incoming
* payloads are included in calculation of exp_data_len here.
*/
prot_bytes = 0;
if (vc.out_size > vc.req_size) {
data_direction = DMA_TO_DEVICE;
exp_data_len = vc.out_size - vc.req_size;
data_iter = vc.out_iter;
} else if (vc.in_size > vc.rsp_size) {
data_direction = DMA_FROM_DEVICE;
exp_data_len = vc.in_size - vc.rsp_size;
iov_iter_init(&in_iter, READ, &vq->iov[vc.out], vc.in,
vc.rsp_size + exp_data_len);
iov_iter_advance(&in_iter, vc.rsp_size);
data_iter = in_iter;
} else {
data_direction = DMA_NONE;
exp_data_len = 0;
}
/*
* If T10_PI header + payload is present, setup prot_iter values
* and recalculate data_iter for vhost_scsi_mapal() mapping to
* host scatterlists via get_user_pages_fast().
*/
if (t10_pi) {
if (v_req_pi.pi_bytesout) {
if (data_direction != DMA_TO_DEVICE) {
vq_err(vq, "Received non zero pi_bytesout,"
" but wrong data_direction\n");
goto err;
}
prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesout);
} else if (v_req_pi.pi_bytesin) {
if (data_direction != DMA_FROM_DEVICE) {
vq_err(vq, "Received non zero pi_bytesin,"
" but wrong data_direction\n");
goto err;
}
prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesin);
}
/*
* Set prot_iter to data_iter and truncate it to
* prot_bytes, and advance data_iter past any
* preceeding prot_bytes that may be present.
*
* Also fix up the exp_data_len to reflect only the
* actual data payload length.
*/
if (prot_bytes) {
exp_data_len -= prot_bytes;
prot_iter = data_iter;
iov_iter_truncate(&prot_iter, prot_bytes);
iov_iter_advance(&data_iter, prot_bytes);
}
tag = vhost64_to_cpu(vq, v_req_pi.tag);
task_attr = v_req_pi.task_attr;
cdb = &v_req_pi.cdb[0];
lun = ((v_req_pi.lun[2] << 8) | v_req_pi.lun[3]) & 0x3FFF;
} else {
tag = vhost64_to_cpu(vq, v_req.tag);
task_attr = v_req.task_attr;
cdb = &v_req.cdb[0];
lun = ((v_req.lun[2] << 8) | v_req.lun[3]) & 0x3FFF;
}
/*
* Check that the received CDB size does not exceeded our
* hardcoded max for vhost-scsi, then get a pre-allocated
* cmd descriptor for the new virtio-scsi tag.
*
* TODO what if cdb was too small for varlen cdb header?
*/
if (unlikely(scsi_command_size(cdb) > VHOST_SCSI_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(cdb), VHOST_SCSI_MAX_CDB_SIZE);
goto err;
}
cmd = vhost_scsi_get_tag(vq, tpg, cdb, tag, lun, task_attr,
exp_data_len + prot_bytes,
data_direction);
if (IS_ERR(cmd)) {
vq_err(vq, "vhost_scsi_get_tag failed %ld\n",
PTR_ERR(cmd));
goto err;
}
cmd->tvc_vhost = vs;
cmd->tvc_vq = vq;
cmd->tvc_resp_iov = vq->iov[vc.out];
cmd->tvc_in_iovs = vc.in;
pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n",
cmd->tvc_cdb[0], cmd->tvc_lun);
pr_debug("cmd: %p exp_data_len: %d, prot_bytes: %d data_direction:"
" %d\n", cmd, exp_data_len, prot_bytes, data_direction);
if (data_direction != DMA_NONE) {
if (unlikely(vhost_scsi_mapal(cmd, prot_bytes,
&prot_iter, exp_data_len,
&data_iter))) {
vq_err(vq, "Failed to map iov to sgl\n");
vhost_scsi_release_cmd(&cmd->tvc_se_cmd);
goto err;
}
}
/*
* Save the descriptor from vhost_get_vq_desc() to be used to
* complete the virtio-scsi request in TCM callback context via
* vhost_scsi_queue_data_in() and vhost_scsi_queue_status()
*/
cmd->tvc_vq_desc = vc.head;
/*
* Dispatch cmd descriptor for cmwq execution in process
* context provided by vhost_scsi_workqueue. This also ensures
* cmd is executed on the same kworker CPU as this vhost
* thread to gain positive L2 cache locality effects.
*/
INIT_WORK(&cmd->work, vhost_scsi_submission_work);
queue_work(vhost_scsi_workqueue, &cmd->work);
ret = 0;
err:
/*
* ENXIO: No more requests, or read error, wait for next kick
* EINVAL: Invalid response buffer, drop the request
* EIO: Respond with bad target
* EAGAIN: Pending request
*/
if (ret == -ENXIO)
break;
else if (ret == -EIO)
vhost_scsi_send_bad_target(vs, vq, vc.head, vc.out);
} while (likely(!vhost_exceeds_weight(vq, ++c, 0)));
out:
mutex_unlock(&vq->mutex);
}
static void
vhost_scsi_send_tmf_reject(struct vhost_scsi *vs,
struct vhost_virtqueue *vq,
struct vhost_scsi_ctx *vc)
{
struct virtio_scsi_ctrl_tmf_resp rsp;
struct iov_iter iov_iter;
int ret;
pr_debug("%s\n", __func__);
memset(&rsp, 0, sizeof(rsp));
rsp.response = VIRTIO_SCSI_S_FUNCTION_REJECTED;
iov_iter_init(&iov_iter, READ, &vq->iov[vc->out], vc->in, sizeof(rsp));
ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter);
if (likely(ret == sizeof(rsp)))
vhost_add_used_and_signal(&vs->dev, vq, vc->head, 0);
else
pr_err("Faulted on virtio_scsi_ctrl_tmf_resp\n");
}
static void
vhost_scsi_send_an_resp(struct vhost_scsi *vs,
struct vhost_virtqueue *vq,
struct vhost_scsi_ctx *vc)
{
struct virtio_scsi_ctrl_an_resp rsp;
struct iov_iter iov_iter;
int ret;
pr_debug("%s\n", __func__);
memset(&rsp, 0, sizeof(rsp)); /* event_actual = 0 */
rsp.response = VIRTIO_SCSI_S_OK;
iov_iter_init(&iov_iter, READ, &vq->iov[vc->out], vc->in, sizeof(rsp));
ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter);
if (likely(ret == sizeof(rsp)))
vhost_add_used_and_signal(&vs->dev, vq, vc->head, 0);
else
pr_err("Faulted on virtio_scsi_ctrl_an_resp\n");
}
static void
vhost_scsi_ctl_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
{
union {
__virtio32 type;
struct virtio_scsi_ctrl_an_req an;
struct virtio_scsi_ctrl_tmf_req tmf;
} v_req;
struct vhost_scsi_ctx vc;
size_t typ_size;
int ret, c = 0;
mutex_lock(&vq->mutex);
/*
* We can handle the vq only after the endpoint is setup by calling the
* VHOST_SCSI_SET_ENDPOINT ioctl.
*/
if (!vq->private_data)
goto out;
memset(&vc, 0, sizeof(vc));
vhost_disable_notify(&vs->dev, vq);
do {
ret = vhost_scsi_get_desc(vs, vq, &vc);
if (ret)
goto err;
/*
* Get the request type first in order to setup
* other parameters dependent on the type.
*/
vc.req = &v_req.type;
typ_size = sizeof(v_req.type);
if (unlikely(!copy_from_iter_full(vc.req, typ_size,
&vc.out_iter))) {
vq_err(vq, "Faulted on copy_from_iter tmf type\n");
/*
* The size of the response buffer depends on the
* request type and must be validated against it.
* Since the request type is not known, don't send
* a response.
*/
continue;
}
switch (v_req.type) {
case VIRTIO_SCSI_T_TMF:
vc.req = &v_req.tmf;
vc.req_size = sizeof(struct virtio_scsi_ctrl_tmf_req);
vc.rsp_size = sizeof(struct virtio_scsi_ctrl_tmf_resp);
vc.lunp = &v_req.tmf.lun[0];
vc.target = &v_req.tmf.lun[1];
break;
case VIRTIO_SCSI_T_AN_QUERY:
case VIRTIO_SCSI_T_AN_SUBSCRIBE:
vc.req = &v_req.an;
vc.req_size = sizeof(struct virtio_scsi_ctrl_an_req);
vc.rsp_size = sizeof(struct virtio_scsi_ctrl_an_resp);
vc.lunp = &v_req.an.lun[0];
vc.target = NULL;
break;
default:
vq_err(vq, "Unknown control request %d", v_req.type);
continue;
}
/*
* Validate the size of request and response buffers.
* Check for a sane response buffer so we can report
* early errors back to the guest.
*/
ret = vhost_scsi_chk_size(vq, &vc);
if (ret)
goto err;
/*
* Get the rest of the request now that its size is known.
*/
vc.req += typ_size;
vc.req_size -= typ_size;
ret = vhost_scsi_get_req(vq, &vc, NULL);
if (ret)
goto err;
if (v_req.type == VIRTIO_SCSI_T_TMF)
vhost_scsi_send_tmf_reject(vs, vq, &vc);
else
vhost_scsi_send_an_resp(vs, vq, &vc);
err:
/*
* ENXIO: No more requests, or read error, wait for next kick
* EINVAL: Invalid response buffer, drop the request
* EIO: Respond with bad target
* EAGAIN: Pending request
*/
if (ret == -ENXIO)
break;
else if (ret == -EIO)
vhost_scsi_send_bad_target(vs, vq, vc.head, vc.out);
} while (likely(!vhost_exceeds_weight(vq, ++c, 0)));
out:
mutex_unlock(&vq->mutex);
}
static void vhost_scsi_ctl_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);
pr_debug("%s: The handling func for control queue.\n", __func__);
vhost_scsi_ctl_handle_vq(vs, vq);
}
static void
vhost_scsi_send_evt(struct vhost_scsi *vs,
struct vhost_scsi_tpg *tpg,
struct se_lun *lun,
u32 event,
u32 reason)
{
struct vhost_scsi_evt *evt;
evt = vhost_scsi_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;
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)
vhost_scsi_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 */
vhost_scsi_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, vhost_scsi_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
* vhost_scsi_tpg with an active struct vhost_scsi_nexus
*
* The lock nesting rule is:
* vhost_scsi_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 se_portal_group *se_tpg;
struct vhost_scsi_tport *tv_tport;
struct vhost_scsi_tpg *tpg;
struct vhost_scsi_tpg **vs_tpg;
struct vhost_virtqueue *vq;
int index, ret, i, len;
bool match = false;
mutex_lock(&vhost_scsi_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(tpg, &vhost_scsi_list, tv_tpg_list) {
mutex_lock(&tpg->tv_tpg_mutex);
if (!tpg->tpg_nexus) {
mutex_unlock(&tpg->tv_tpg_mutex);
continue;
}
if (tpg->tv_tpg_vhost_count != 0) {
mutex_unlock(&tpg->tv_tpg_mutex);
continue;
}
tv_tport = tpg->tport;
if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
if (vs->vs_tpg && vs->vs_tpg[tpg->tport_tpgt]) {
kfree(vs_tpg);
mutex_unlock(&tpg->tv_tpg_mutex);
ret = -EEXIST;
goto out;
}
/*
* In order to ensure individual vhost-scsi configfs
* groups cannot be removed while in use by vhost ioctl,
* go ahead and take an explicit se_tpg->tpg_group.cg_item
* dependency now.
*/
se_tpg = &tpg->se_tpg;
ret = target_depend_item(&se_tpg->tpg_group.cg_item);
if (ret) {
pr_warn("target_depend_item() failed: %d\n", ret);
kfree(vs_tpg);
mutex_unlock(&tpg->tv_tpg_mutex);
goto out;
}
tpg->tv_tpg_vhost_count++;
tpg->vhost_scsi = vs;
vs_tpg[tpg->tport_tpgt] = tpg;
match = true;
}
mutex_unlock(&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;
mutex_lock(&vq->mutex);
vq->private_data = vs_tpg;
vhost_vq_init_access(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(&vhost_scsi_mutex);
return ret;
}
static int
vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
struct vhost_scsi_target *t)
{
struct se_portal_group *se_tpg;
struct vhost_scsi_tport *tv_tport;
struct vhost_scsi_tpg *tpg;
struct vhost_virtqueue *vq;
bool match = false;
int index, ret, i;
u8 target;
mutex_lock(&vhost_scsi_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;
tpg = vs->vs_tpg[target];
if (!tpg)
continue;
mutex_lock(&tpg->tv_tpg_mutex);
tv_tport = 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, tpg->tport_tpgt: %hu"
" does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
tv_tport->tport_name, tpg->tport_tpgt,
t->vhost_wwpn, t->vhost_tpgt);
ret = -EINVAL;
goto err_tpg;
}
tpg->tv_tpg_vhost_count--;
tpg->vhost_scsi = NULL;
vs->vs_tpg[target] = NULL;
match = true;
mutex_unlock(&tpg->tv_tpg_mutex);
/*
* Release se_tpg->tpg_group.cg_item configfs dependency now
* to allow vhost-scsi WWPN se_tpg->tpg_group shutdown to occur.
*/
se_tpg = &tpg->se_tpg;
target_undepend_item(&se_tpg->tpg_group.cg_item);
}
if (match) {
for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
vq = &vs->vqs[i].vq;
mutex_lock(&vq->mutex);
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(&vhost_scsi_mutex);
return 0;
err_tpg:
mutex_unlock(&tpg->tv_tpg_mutex);
err_dev:
mutex_unlock(&vs->dev.mutex);
mutex_unlock(&vhost_scsi_mutex);
return ret;
}
static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features)
{
struct vhost_virtqueue *vq;
int i;
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;
}
for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
vq = &vs->vqs[i].vq;
mutex_lock(&vq->mutex);
vq->acked_features = features;
mutex_unlock(&vq->mutex);
}
mutex_unlock(&vs->dev.mutex);
return 0;
}
static int vhost_scsi_open(struct inode *inode, struct file *f)
{
struct vhost_scsi *vs;
struct vhost_virtqueue **vqs;
int r = -ENOMEM, i;
vs = kzalloc(sizeof(*vs), GFP_KERNEL | __GFP_NOWARN | __GFP_RETRY_MAYFAIL);
if (!vs) {
vs = vzalloc(sizeof(*vs));
if (!vs)
goto err_vs;
}
vqs = kmalloc_array(VHOST_SCSI_MAX_VQ, sizeof(*vqs), GFP_KERNEL);
if (!vqs)
goto err_vqs;
vhost_work_init(&vs->vs_completion_work, vhost_scsi_complete_cmd_work);
vhost_work_init(&vs->vs_event_work, vhost_scsi_evt_work);
vs->vs_events_nr = 0;
vs->vs_events_missed = false;
vqs[VHOST_SCSI_VQ_CTL] = &vs->vqs[VHOST_SCSI_VQ_CTL].vq;
vqs[VHOST_SCSI_VQ_EVT] = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
vs->vqs[VHOST_SCSI_VQ_CTL].vq.handle_kick = vhost_scsi_ctl_handle_kick;
vs->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] = &vs->vqs[i].vq;
vs->vqs[i].vq.handle_kick = vhost_scsi_handle_kick;
}
vhost_dev_init(&vs->dev, vqs, VHOST_SCSI_MAX_VQ, UIO_MAXIOV,
VHOST_SCSI_WEIGHT, 0, NULL);
vhost_scsi_init_inflight(vs, NULL);
f->private_data = vs;
return 0;
err_vqs:
kvfree(vs);
err_vs:
return r;
}
static int vhost_scsi_release(struct inode *inode, struct file *f)
{
struct vhost_scsi *vs = f->private_data;
struct vhost_scsi_target t;
mutex_lock(&vs->dev.mutex);
memcpy(t.vhost_wwpn, vs->vs_vhost_wwpn, sizeof(t.vhost_wwpn));
mutex_unlock(&vs->dev.mutex);
vhost_scsi_clear_endpoint(vs, &t);
vhost_dev_stop(&vs->dev);
vhost_dev_cleanup(&vs->dev);
/* Jobs can re-queue themselves in evt kick handler. Do extra flush. */
vhost_scsi_flush(vs);
kfree(vs->dev.vqs);
kvfree(vs);
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;
}
}
static const struct file_operations vhost_scsi_fops = {
.owner = THIS_MODULE,
.release = vhost_scsi_release,
.unlocked_ioctl = vhost_scsi_ioctl,
.compat_ioctl = compat_ptr_ioctl,
.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 void vhost_scsi_deregister(void)
{
misc_deregister(&vhost_scsi_misc);
}
static char *vhost_scsi_dump_proto_id(struct vhost_scsi_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
vhost_scsi_do_plug(struct vhost_scsi_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 (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);
if (vhost_has_feature(vq, VIRTIO_SCSI_F_HOTPLUG))
vhost_scsi_send_evt(vs, tpg, lun,
VIRTIO_SCSI_T_TRANSPORT_RESET, reason);
mutex_unlock(&vq->mutex);
mutex_unlock(&vs->dev.mutex);
}
static void vhost_scsi_hotplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
{
vhost_scsi_do_plug(tpg, lun, true);
}
static void vhost_scsi_hotunplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
{
vhost_scsi_do_plug(tpg, lun, false);
}
static int vhost_scsi_port_link(struct se_portal_group *se_tpg,
struct se_lun *lun)
{
struct vhost_scsi_tpg *tpg = container_of(se_tpg,
struct vhost_scsi_tpg, se_tpg);
mutex_lock(&vhost_scsi_mutex);
mutex_lock(&tpg->tv_tpg_mutex);
tpg->tv_tpg_port_count++;
mutex_unlock(&tpg->tv_tpg_mutex);
vhost_scsi_hotplug(tpg, lun);
mutex_unlock(&vhost_scsi_mutex);
return 0;
}
static void vhost_scsi_port_unlink(struct se_portal_group *se_tpg,
struct se_lun *lun)
{
struct vhost_scsi_tpg *tpg = container_of(se_tpg,
struct vhost_scsi_tpg, se_tpg);
mutex_lock(&vhost_scsi_mutex);
mutex_lock(&tpg->tv_tpg_mutex);
tpg->tv_tpg_port_count--;
mutex_unlock(&tpg->tv_tpg_mutex);
vhost_scsi_hotunplug(tpg, lun);
mutex_unlock(&vhost_scsi_mutex);
}
static void vhost_scsi_free_cmd_map_res(struct se_session *se_sess)
{
struct vhost_scsi_cmd *tv_cmd;
unsigned int i;
if (!se_sess->sess_cmd_map)
return;
for (i = 0; i < VHOST_SCSI_DEFAULT_TAGS; i++) {
tv_cmd = &((struct vhost_scsi_cmd *)se_sess->sess_cmd_map)[i];
kfree(tv_cmd->tvc_sgl);
kfree(tv_cmd->tvc_prot_sgl);
kfree(tv_cmd->tvc_upages);
}
}
static ssize_t vhost_scsi_tpg_attrib_fabric_prot_type_store(
struct config_item *item, const char *page, size_t count)
{
struct se_portal_group *se_tpg = attrib_to_tpg(item);
struct vhost_scsi_tpg *tpg = container_of(se_tpg,
struct vhost_scsi_tpg, se_tpg);
unsigned long val;
int ret = kstrtoul(page, 0, &val);
if (ret) {
pr_err("kstrtoul() returned %d for fabric_prot_type\n", ret);
return ret;
}
if (val != 0 && val != 1 && val != 3) {
pr_err("Invalid vhost_scsi fabric_prot_type: %lu\n", val);
return -EINVAL;
}
tpg->tv_fabric_prot_type = val;
return count;
}
static ssize_t vhost_scsi_tpg_attrib_fabric_prot_type_show(
struct config_item *item, char *page)
{
struct se_portal_group *se_tpg = attrib_to_tpg(item);
struct vhost_scsi_tpg *tpg = container_of(se_tpg,
struct vhost_scsi_tpg, se_tpg);
return sprintf(page, "%d\n", tpg->tv_fabric_prot_type);
}
CONFIGFS_ATTR(vhost_scsi_tpg_attrib_, fabric_prot_type);
static struct configfs_attribute *vhost_scsi_tpg_attrib_attrs[] = {
&vhost_scsi_tpg_attrib_attr_fabric_prot_type,
NULL,
};
static int vhost_scsi_nexus_cb(struct se_portal_group *se_tpg,
struct se_session *se_sess, void *p)
{
struct vhost_scsi_cmd *tv_cmd;
unsigned int i;
for (i = 0; i < VHOST_SCSI_DEFAULT_TAGS; i++) {
tv_cmd = &((struct vhost_scsi_cmd *)se_sess->sess_cmd_map)[i];
tv_cmd->tvc_sgl = kcalloc(VHOST_SCSI_PREALLOC_SGLS,
sizeof(struct scatterlist),
GFP_KERNEL);
if (!tv_cmd->tvc_sgl) {
pr_err("Unable to allocate tv_cmd->tvc_sgl\n");
goto out;
}
tv_cmd->tvc_upages = kcalloc(VHOST_SCSI_PREALLOC_UPAGES,
sizeof(struct page *),
GFP_KERNEL);
if (!tv_cmd->tvc_upages) {
pr_err("Unable to allocate tv_cmd->tvc_upages\n");
goto out;
}
tv_cmd->tvc_prot_sgl = kcalloc(VHOST_SCSI_PREALLOC_PROT_SGLS,
sizeof(struct scatterlist),
GFP_KERNEL);
if (!tv_cmd->tvc_prot_sgl) {
pr_err("Unable to allocate tv_cmd->tvc_prot_sgl\n");
goto out;
}
}
return 0;
out:
vhost_scsi_free_cmd_map_res(se_sess);
return -ENOMEM;
}
static int vhost_scsi_make_nexus(struct vhost_scsi_tpg *tpg,
const char *name)
{
struct vhost_scsi_nexus *tv_nexus;
mutex_lock(&tpg->tv_tpg_mutex);
if (tpg->tpg_nexus) {
mutex_unlock(&tpg->tv_tpg_mutex);
pr_debug("tpg->tpg_nexus already exists\n");
return -EEXIST;
}
tv_nexus = kzalloc(sizeof(*tv_nexus), GFP_KERNEL);
if (!tv_nexus) {
mutex_unlock(&tpg->tv_tpg_mutex);
pr_err("Unable to allocate struct vhost_scsi_nexus\n");
return -ENOMEM;
}
/*
* Since we are running in 'demo mode' this call with generate a
* struct se_node_acl for the vhost_scsi struct se_portal_group with
* the SCSI Initiator port name of the passed configfs group 'name'.
*/
tv_nexus->tvn_se_sess = target_setup_session(&tpg->se_tpg,
VHOST_SCSI_DEFAULT_TAGS,
sizeof(struct vhost_scsi_cmd),
TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS,
(unsigned char *)name, tv_nexus,
vhost_scsi_nexus_cb);
if (IS_ERR(tv_nexus->tvn_se_sess)) {
mutex_unlock(&tpg->tv_tpg_mutex);
kfree(tv_nexus);
return -ENOMEM;
}
tpg->tpg_nexus = tv_nexus;
mutex_unlock(&tpg->tv_tpg_mutex);
return 0;
}
static int vhost_scsi_drop_nexus(struct vhost_scsi_tpg *tpg)
{
struct se_session *se_sess;
struct vhost_scsi_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", vhost_scsi_dump_proto_id(tpg->tport),
tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
vhost_scsi_free_cmd_map_res(se_sess);
/*
* Release the SCSI I_T Nexus to the emulated vhost Target Port
*/
target_remove_session(se_sess);
tpg->tpg_nexus = NULL;
mutex_unlock(&tpg->tv_tpg_mutex);
kfree(tv_nexus);
return 0;
}
static ssize_t vhost_scsi_tpg_nexus_show(struct config_item *item, char *page)
{
struct se_portal_group *se_tpg = to_tpg(item);
struct vhost_scsi_tpg *tpg = container_of(se_tpg,
struct vhost_scsi_tpg, se_tpg);
struct vhost_scsi_nexus *tv_nexus;
ssize_t ret;
mutex_lock(&tpg->tv_tpg_mutex);
tv_nexus = tpg->tpg_nexus;
if (!tv_nexus) {
mutex_unlock(&tpg->tv_tpg_mutex);
return -ENODEV;
}
ret = snprintf(page, PAGE_SIZE, "%s\n",
tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
mutex_unlock(&tpg->tv_tpg_mutex);
return ret;
}
static ssize_t vhost_scsi_tpg_nexus_store(struct config_item *item,
const char *page, size_t count)
{
struct se_portal_group *se_tpg = to_tpg(item);
struct vhost_scsi_tpg *tpg = container_of(se_tpg,
struct vhost_scsi_tpg, se_tpg);
struct vhost_scsi_tport *tport_wwn = tpg->tport;
unsigned char i_port[VHOST_SCSI_NAMELEN], *ptr, *port_ptr;
int ret;
/*
* Shutdown the active I_T nexus if 'NULL' is passed..
*/
if (!strncmp(page, "NULL", 4)) {
ret = vhost_scsi_drop_nexus(tpg);
return (!ret) ? count : ret;
}
/*
* Otherwise make sure the passed virtual Initiator port WWN matches
* the fabric protocol_id set in vhost_scsi_make_tport(), and call
* vhost_scsi_make_nexus().
*/
if (strlen(page) >= VHOST_SCSI_NAMELEN) {
pr_err("Emulated NAA Sas Address: %s, exceeds"
" max: %d\n", page, VHOST_SCSI_NAMELEN);
return -EINVAL;
}
snprintf(&i_port[0], VHOST_SCSI_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,
vhost_scsi_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,
vhost_scsi_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,
vhost_scsi_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 = vhost_scsi_make_nexus(tpg, port_ptr);
if (ret < 0)
return ret;
return count;
}
CONFIGFS_ATTR(vhost_scsi_tpg_, nexus);
static struct configfs_attribute *vhost_scsi_tpg_attrs[] = {
&vhost_scsi_tpg_attr_nexus,
NULL,
};
static struct se_portal_group *
vhost_scsi_make_tpg(struct se_wwn *wwn, const char *name)
{
struct vhost_scsi_tport *tport = container_of(wwn,
struct vhost_scsi_tport, tport_wwn);
struct vhost_scsi_tpg *tpg;
u16 tpgt;
int ret;
if (strstr(name, "tpgt_") != name)
return ERR_PTR(-EINVAL);
if (kstrtou16(name + 5, 10, &tpgt) || tpgt >= VHOST_SCSI_MAX_TARGET)
return ERR_PTR(-EINVAL);
tpg = kzalloc(sizeof(*tpg), GFP_KERNEL);
if (!tpg) {
pr_err("Unable to allocate struct vhost_scsi_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(wwn, &tpg->se_tpg, tport->tport_proto_id);
if (ret < 0) {
kfree(tpg);
return NULL;
}
mutex_lock(&vhost_scsi_mutex);
list_add_tail(&tpg->tv_tpg_list, &vhost_scsi_list);
mutex_unlock(&vhost_scsi_mutex);
return &tpg->se_tpg;
}
static void vhost_scsi_drop_tpg(struct se_portal_group *se_tpg)
{
struct vhost_scsi_tpg *tpg = container_of(se_tpg,
struct vhost_scsi_tpg, se_tpg);
mutex_lock(&vhost_scsi_mutex);
list_del(&tpg->tv_tpg_list);
mutex_unlock(&vhost_scsi_mutex);
/*
* Release the virtual I_T Nexus for this vhost TPG
*/
vhost_scsi_drop_nexus(tpg);
/*
* Deregister the se_tpg from TCM..
*/
core_tpg_deregister(se_tpg);
kfree(tpg);
}
static struct se_wwn *
vhost_scsi_make_tport(struct target_fabric_configfs *tf,
struct config_group *group,
const char *name)
{
struct vhost_scsi_tport *tport;
char *ptr;
u64 wwpn = 0;
int off = 0;
/* if (vhost_scsi_parse_wwn(name, &wwpn, 1) < 0)
return ERR_PTR(-EINVAL); */
tport = kzalloc(sizeof(*tport), GFP_KERNEL);
if (!tport) {
pr_err("Unable to allocate struct vhost_scsi_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) >= VHOST_SCSI_NAMELEN) {
pr_err("Emulated %s Address: %s, exceeds"
" max: %d\n", name, vhost_scsi_dump_proto_id(tport),
VHOST_SCSI_NAMELEN);
kfree(tport);
return ERR_PTR(-EINVAL);
}
snprintf(&tport->tport_name[0], VHOST_SCSI_NAMELEN, "%s", &name[off]);
pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target"
" %s Address: %s\n", vhost_scsi_dump_proto_id(tport), name);
return &tport->tport_wwn;
}
static void vhost_scsi_drop_tport(struct se_wwn *wwn)
{
struct vhost_scsi_tport *tport = container_of(wwn,
struct vhost_scsi_tport, tport_wwn);
pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target"
" %s Address: %s\n", vhost_scsi_dump_proto_id(tport),
tport->tport_name);
kfree(tport);
}
static ssize_t
vhost_scsi_wwn_version_show(struct config_item *item, char *page)
{
return sprintf(page, "TCM_VHOST fabric module %s on %s/%s"
"on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
utsname()->machine);
}
CONFIGFS_ATTR_RO(vhost_scsi_wwn_, version);
static struct configfs_attribute *vhost_scsi_wwn_attrs[] = {
&vhost_scsi_wwn_attr_version,
NULL,
};
static const struct target_core_fabric_ops vhost_scsi_ops = {
.module = THIS_MODULE,
.fabric_name = "vhost",
.max_data_sg_nents = VHOST_SCSI_PREALLOC_SGLS,
.tpg_get_wwn = vhost_scsi_get_fabric_wwn,
.tpg_get_tag = vhost_scsi_get_tpgt,
.tpg_check_demo_mode = vhost_scsi_check_true,
.tpg_check_demo_mode_cache = vhost_scsi_check_true,
.tpg_check_demo_mode_write_protect = vhost_scsi_check_false,
.tpg_check_prod_mode_write_protect = vhost_scsi_check_false,
.tpg_check_prot_fabric_only = vhost_scsi_check_prot_fabric_only,
.tpg_get_inst_index = vhost_scsi_tpg_get_inst_index,
.release_cmd = vhost_scsi_release_cmd,
.check_stop_free = vhost_scsi_check_stop_free,
.sess_get_index = vhost_scsi_sess_get_index,
.sess_get_initiator_sid = NULL,
.write_pending = vhost_scsi_write_pending,
.set_default_node_attributes = vhost_scsi_set_default_node_attrs,
.get_cmd_state = vhost_scsi_get_cmd_state,
.queue_data_in = vhost_scsi_queue_data_in,
.queue_status = vhost_scsi_queue_status,
.queue_tm_rsp = vhost_scsi_queue_tm_rsp,
.aborted_task = vhost_scsi_aborted_task,
/*
* Setup callers for generic logic in target_core_fabric_configfs.c
*/
.fabric_make_wwn = vhost_scsi_make_tport,
.fabric_drop_wwn = vhost_scsi_drop_tport,
.fabric_make_tpg = vhost_scsi_make_tpg,
.fabric_drop_tpg = vhost_scsi_drop_tpg,
.fabric_post_link = vhost_scsi_port_link,
.fabric_pre_unlink = vhost_scsi_port_unlink,
.tfc_wwn_attrs = vhost_scsi_wwn_attrs,
.tfc_tpg_base_attrs = vhost_scsi_tpg_attrs,
.tfc_tpg_attrib_attrs = vhost_scsi_tpg_attrib_attrs,
};
static int __init vhost_scsi_init(void)
{
int ret = -ENOMEM;
pr_debug("TCM_VHOST fabric module %s on %s/%s"
" on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
utsname()->machine);
/*
* Use our own dedicated workqueue for submitting I/O into
* target core to avoid contention within system_wq.
*/
vhost_scsi_workqueue = alloc_workqueue("vhost_scsi", 0, 0);
if (!vhost_scsi_workqueue)
goto out;
ret = vhost_scsi_register();
if (ret < 0)
goto out_destroy_workqueue;
ret = target_register_template(&vhost_scsi_ops);
if (ret < 0)
goto out_vhost_scsi_deregister;
return 0;
out_vhost_scsi_deregister:
vhost_scsi_deregister();
out_destroy_workqueue:
destroy_workqueue(vhost_scsi_workqueue);
out:
return ret;
};
static void vhost_scsi_exit(void)
{
target_unregister_template(&vhost_scsi_ops);
vhost_scsi_deregister();
destroy_workqueue(vhost_scsi_workqueue);
};
MODULE_DESCRIPTION("VHOST_SCSI series fabric driver");
MODULE_ALIAS("tcm_vhost");
MODULE_LICENSE("GPL");
module_init(vhost_scsi_init);
module_exit(vhost_scsi_exit);