linux-stable/drivers/vhost/scsi.c
Mike Christie 0869419947 scsi: target: core: Add gfp_t arg to target_cmd_init_cdb()
tcm_loop could be used like a normal block device, so we can't use
GFP_KERNEL and should use GFP_NOIO. This adds a gfp_t arg to
target_cmd_init_cdb() and converts the users. For every driver but loop
GFP_KERNEL is kept.

This will also be useful in subsequent patches where loop needs to do
target_submit_prep() from interrupt context to get a ref to the se_device,
and so it will need to use GFP_ATOMIC.

Link: https://lore.kernel.org/r/20210227170006.5077-16-michael.christie@oracle.com
Tested-by: Laurence Oberman <loberman@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-03-04 17:37:02 -05:00

2524 lines
66 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_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 list_head tmf_queue;
};
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_cmd *scsi_cmds;
struct sbitmap scsi_tags;
int max_cmds;
};
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 */
};
struct vhost_scsi_tmf {
struct vhost_work vwork;
struct vhost_scsi_tpg *tpg;
struct vhost_scsi *vhost;
struct vhost_scsi_virtqueue *svq;
struct list_head queue_entry;
struct se_cmd se_cmd;
u8 scsi_resp;
struct vhost_scsi_inflight *inflight;
struct iovec resp_iov;
int in_iovs;
int vq_desc;
};
/*
* 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_res(struct se_cmd *se_cmd)
{
struct vhost_scsi_cmd *tv_cmd = container_of(se_cmd,
struct vhost_scsi_cmd, tvc_se_cmd);
struct vhost_scsi_virtqueue *svq = container_of(tv_cmd->tvc_vq,
struct vhost_scsi_virtqueue, vq);
struct vhost_scsi_inflight *inflight = tv_cmd->inflight;
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]));
}
sbitmap_clear_bit(&svq->scsi_tags, se_cmd->map_tag);
vhost_scsi_put_inflight(inflight);
}
static void vhost_scsi_release_tmf_res(struct vhost_scsi_tmf *tmf)
{
struct vhost_scsi_tpg *tpg = tmf->tpg;
struct vhost_scsi_inflight *inflight = tmf->inflight;
mutex_lock(&tpg->tv_tpg_mutex);
list_add_tail(&tpg->tmf_queue, &tmf->queue_entry);
mutex_unlock(&tpg->tv_tpg_mutex);
vhost_scsi_put_inflight(inflight);
}
static void vhost_scsi_release_cmd(struct se_cmd *se_cmd)
{
if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB) {
struct vhost_scsi_tmf *tmf = container_of(se_cmd,
struct vhost_scsi_tmf, se_cmd);
vhost_work_queue(&tmf->vhost->dev, &tmf->vwork);
} else {
struct vhost_scsi_cmd *cmd = container_of(se_cmd,
struct vhost_scsi_cmd, tvc_se_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 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 int vhost_scsi_queue_data_in(struct se_cmd *se_cmd)
{
transport_generic_free_cmd(se_cmd, 0);
return 0;
}
static int vhost_scsi_queue_status(struct se_cmd *se_cmd)
{
transport_generic_free_cmd(se_cmd, 0);
return 0;
}
static void vhost_scsi_queue_tm_rsp(struct se_cmd *se_cmd)
{
struct vhost_scsi_tmf *tmf = container_of(se_cmd, struct vhost_scsi_tmf,
se_cmd);
tmf->scsi_resp = se_cmd->se_tmr_req->response;
transport_generic_free_cmd(&tmf->se_cmd, 0);
}
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 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 (!vhost_vq_get_backend(vq)) {
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_release_cmd_res(se_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_cmd(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_virtqueue *svq = container_of(vq,
struct vhost_scsi_virtqueue, vq);
struct vhost_scsi_cmd *cmd;
struct vhost_scsi_nexus *tv_nexus;
struct scatterlist *sg, *prot_sg;
struct page **pages;
int tag;
tv_nexus = tpg->tpg_nexus;
if (!tv_nexus) {
pr_err("Unable to locate active struct vhost_scsi_nexus\n");
return ERR_PTR(-EIO);
}
tag = sbitmap_get(&svq->scsi_tags);
if (tag < 0) {
pr_err("Unable to obtain tag for vhost_scsi_cmd\n");
return ERR_PTR(-ENOMEM);
}
cmd = &svq->scsi_cmds[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_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;
/* 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;
target_init_cmd(se_cmd, tv_nexus->tvn_se_sess, &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);
if (target_submit_prep(se_cmd, cmd->tvc_cdb, sg_ptr,
cmd->tvc_sgl_count, NULL, 0, sg_prot_ptr,
cmd->tvc_prot_sgl_count, GFP_KERNEL))
return;
target_submit(se_cmd);
}
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 = vhost_vq_get_backend(vq); /* 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 u16 vhost_buf_to_lun(u8 *lun_buf)
{
return ((lun_buf[2] << 8) | lun_buf[3]) & 0x3FFF;
}
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 = vhost_vq_get_backend(vq);
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 = vhost_buf_to_lun(v_req_pi.lun);
} else {
tag = vhost64_to_cpu(vq, v_req.tag);
task_attr = v_req.task_attr;
cdb = &v_req.cdb[0];
lun = vhost_buf_to_lun(v_req.lun);
}
/*
* 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_cmd(vq, tpg, cdb, tag, lun, task_attr,
exp_data_len + prot_bytes,
data_direction);
if (IS_ERR(cmd)) {
vq_err(vq, "vhost_scsi_get_cmd 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_res(&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_resp(struct vhost_scsi *vs, struct vhost_virtqueue *vq,
int in_iovs, int vq_desc, struct iovec *resp_iov,
int tmf_resp_code)
{
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 = tmf_resp_code;
iov_iter_init(&iov_iter, READ, resp_iov, in_iovs, sizeof(rsp));
ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter);
if (likely(ret == sizeof(rsp)))
vhost_add_used_and_signal(&vs->dev, vq, vq_desc, 0);
else
pr_err("Faulted on virtio_scsi_ctrl_tmf_resp\n");
}
static void vhost_scsi_tmf_resp_work(struct vhost_work *work)
{
struct vhost_scsi_tmf *tmf = container_of(work, struct vhost_scsi_tmf,
vwork);
int resp_code;
if (tmf->scsi_resp == TMR_FUNCTION_COMPLETE)
resp_code = VIRTIO_SCSI_S_FUNCTION_SUCCEEDED;
else
resp_code = VIRTIO_SCSI_S_FUNCTION_REJECTED;
vhost_scsi_send_tmf_resp(tmf->vhost, &tmf->svq->vq, tmf->in_iovs,
tmf->vq_desc, &tmf->resp_iov, resp_code);
vhost_scsi_release_tmf_res(tmf);
}
static void
vhost_scsi_handle_tmf(struct vhost_scsi *vs, struct vhost_scsi_tpg *tpg,
struct vhost_virtqueue *vq,
struct virtio_scsi_ctrl_tmf_req *vtmf,
struct vhost_scsi_ctx *vc)
{
struct vhost_scsi_virtqueue *svq = container_of(vq,
struct vhost_scsi_virtqueue, vq);
struct vhost_scsi_tmf *tmf;
if (vhost32_to_cpu(vq, vtmf->subtype) !=
VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET)
goto send_reject;
if (!tpg->tpg_nexus || !tpg->tpg_nexus->tvn_se_sess) {
pr_err("Unable to locate active struct vhost_scsi_nexus for LUN RESET.\n");
goto send_reject;
}
mutex_lock(&tpg->tv_tpg_mutex);
if (list_empty(&tpg->tmf_queue)) {
pr_err("Missing reserve TMF. Could not handle LUN RESET.\n");
mutex_unlock(&tpg->tv_tpg_mutex);
goto send_reject;
}
tmf = list_first_entry(&tpg->tmf_queue, struct vhost_scsi_tmf,
queue_entry);
list_del_init(&tmf->queue_entry);
mutex_unlock(&tpg->tv_tpg_mutex);
tmf->tpg = tpg;
tmf->vhost = vs;
tmf->svq = svq;
tmf->resp_iov = vq->iov[vc->out];
tmf->vq_desc = vc->head;
tmf->in_iovs = vc->in;
tmf->inflight = vhost_scsi_get_inflight(vq);
if (target_submit_tmr(&tmf->se_cmd, tpg->tpg_nexus->tvn_se_sess, NULL,
vhost_buf_to_lun(vtmf->lun), NULL,
TMR_LUN_RESET, GFP_KERNEL, 0,
TARGET_SCF_ACK_KREF) < 0) {
vhost_scsi_release_tmf_res(tmf);
goto send_reject;
}
return;
send_reject:
vhost_scsi_send_tmf_resp(vs, vq, vc->in, vc->head, &vq->iov[vc->out],
VIRTIO_SCSI_S_FUNCTION_REJECTED);
}
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)
{
struct vhost_scsi_tpg *tpg;
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 (!vhost_vq_get_backend(vq))
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 (vhost32_to_cpu(vq, 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, &tpg);
if (ret)
goto err;
if (v_req.type == VIRTIO_SCSI_T_TMF)
vhost_scsi_handle_tmf(vs, tpg, vq, &v_req.tmf, &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 (!vhost_vq_get_backend(vq))
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);
}
static void vhost_scsi_destroy_vq_cmds(struct vhost_virtqueue *vq)
{
struct vhost_scsi_virtqueue *svq = container_of(vq,
struct vhost_scsi_virtqueue, vq);
struct vhost_scsi_cmd *tv_cmd;
unsigned int i;
if (!svq->scsi_cmds)
return;
for (i = 0; i < svq->max_cmds; i++) {
tv_cmd = &svq->scsi_cmds[i];
kfree(tv_cmd->tvc_sgl);
kfree(tv_cmd->tvc_prot_sgl);
kfree(tv_cmd->tvc_upages);
}
sbitmap_free(&svq->scsi_tags);
kfree(svq->scsi_cmds);
svq->scsi_cmds = NULL;
}
static int vhost_scsi_setup_vq_cmds(struct vhost_virtqueue *vq, int max_cmds)
{
struct vhost_scsi_virtqueue *svq = container_of(vq,
struct vhost_scsi_virtqueue, vq);
struct vhost_scsi_cmd *tv_cmd;
unsigned int i;
if (svq->scsi_cmds)
return 0;
if (sbitmap_init_node(&svq->scsi_tags, max_cmds, -1, GFP_KERNEL,
NUMA_NO_NODE, false, true))
return -ENOMEM;
svq->max_cmds = max_cmds;
svq->scsi_cmds = kcalloc(max_cmds, sizeof(*tv_cmd), GFP_KERNEL);
if (!svq->scsi_cmds) {
sbitmap_free(&svq->scsi_tags);
return -ENOMEM;
}
for (i = 0; i < max_cmds; i++) {
tv_cmd = &svq->scsi_cmds[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_destroy_vq_cmds(vq);
return -ENOMEM;
}
/*
* 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]) {
mutex_unlock(&tpg->tv_tpg_mutex);
ret = -EEXIST;
goto undepend;
}
/*
* 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);
mutex_unlock(&tpg->tv_tpg_mutex);
goto undepend;
}
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 = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++) {
vq = &vs->vqs[i].vq;
if (!vhost_vq_is_setup(vq))
continue;
ret = vhost_scsi_setup_vq_cmds(vq, vq->num);
if (ret)
goto destroy_vq_cmds;
}
for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
vq = &vs->vqs[i].vq;
mutex_lock(&vq->mutex);
vhost_vq_set_backend(vq, 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;
goto out;
destroy_vq_cmds:
for (i--; i >= VHOST_SCSI_VQ_IO; i--) {
if (!vhost_vq_get_backend(&vs->vqs[i].vq))
vhost_scsi_destroy_vq_cmds(&vs->vqs[i].vq);
}
undepend:
for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
tpg = vs_tpg[i];
if (tpg) {
tpg->tv_tpg_vhost_count--;
target_undepend_item(&tpg->se_tpg.tpg_group.cg_item);
}
}
kfree(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);
vhost_vq_set_backend(vq, NULL);
mutex_unlock(&vq->mutex);
/*
* Make sure cmds are not running before tearing them
* down.
*/
vhost_scsi_flush(vs);
vhost_scsi_destroy_vq_cmds(vq);
}
}
/*
* 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 = kvzalloc(sizeof(*vs), GFP_KERNEL);
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, true, 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);
struct vhost_scsi_tmf *tmf;
tmf = kzalloc(sizeof(*tmf), GFP_KERNEL);
if (!tmf)
return -ENOMEM;
INIT_LIST_HEAD(&tmf->queue_entry);
vhost_work_init(&tmf->vwork, vhost_scsi_tmf_resp_work);
mutex_lock(&vhost_scsi_mutex);
mutex_lock(&tpg->tv_tpg_mutex);
tpg->tv_tpg_port_count++;
list_add_tail(&tmf->queue_entry, &tpg->tmf_queue);
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);
struct vhost_scsi_tmf *tmf;
mutex_lock(&vhost_scsi_mutex);
mutex_lock(&tpg->tv_tpg_mutex);
tpg->tv_tpg_port_count--;
tmf = list_first_entry(&tpg->tmf_queue, struct vhost_scsi_tmf,
queue_entry);
list_del(&tmf->queue_entry);
kfree(tmf);
mutex_unlock(&tpg->tv_tpg_mutex);
vhost_scsi_hotunplug(tpg, lun);
mutex_unlock(&vhost_scsi_mutex);
}
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_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, 0, 0,
TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS,
(unsigned char *)name, tv_nexus, NULL);
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);
/*
* 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);
INIT_LIST_HEAD(&tpg->tmf_queue);
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);