numam-spdk/lib/vhost/vhost_blk.c
Darek Stojaczyk 6e77b0b68d vhost: make poll group refcount per-session
Change the way we increase poll group reference counts
for round-robin scheduling.

So far we used to increase them whenever someone called
vhost_get_poll_group() and this worked fine for Vhost-Block
which picks a new poll group for each session. Vhost-SCSI,
however, picks only one poll group for all sessions on
a vhost device. This means that some threads will have
multiple Vhost-SCSI pollers but will still appear to the
vhost scheduler as if they had only one.

To fix it, increase poll group refcnt only when sessions
are really being started - in vhost_session_start_done().

Change-Id: I60f0d2101239e5a91138a5afd30c51dc1ccf7c2e
Signed-off-by: Darek Stojaczyk <dariusz.stojaczyk@intel.com>
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/466733
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Vitaliy Mysak <vitaliy.mysak@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Changpeng Liu <changpeng.liu@intel.com>
2019-09-09 01:39:41 +00:00

1050 lines
30 KiB
C

/*-
* BSD LICENSE
*
* Copyright(c) Intel Corporation. All rights reserved.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Intel Corporation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <linux/virtio_blk.h>
#include "spdk/env.h"
#include "spdk/bdev.h"
#include "spdk/bdev_module.h"
#include "spdk/conf.h"
#include "spdk/thread.h"
#include "spdk/likely.h"
#include "spdk/string.h"
#include "spdk/util.h"
#include "spdk/vhost.h"
#include "vhost_internal.h"
struct spdk_vhost_blk_task {
struct spdk_bdev_io *bdev_io;
struct spdk_vhost_blk_session *bvsession;
struct spdk_vhost_virtqueue *vq;
volatile uint8_t *status;
uint16_t req_idx;
/* for io wait */
struct spdk_bdev_io_wait_entry bdev_io_wait;
/* If set, the task is currently used for I/O processing. */
bool used;
/** Number of bytes that were written. */
uint32_t used_len;
uint16_t iovcnt;
struct iovec iovs[SPDK_VHOST_IOVS_MAX];
};
struct spdk_vhost_blk_dev {
struct spdk_vhost_dev vdev;
struct spdk_bdev *bdev;
struct spdk_bdev_desc *bdev_desc;
bool readonly;
};
struct spdk_vhost_blk_session {
/* The parent session must be the very first field in this struct */
struct spdk_vhost_session vsession;
struct spdk_vhost_blk_dev *bvdev;
struct spdk_poller *requestq_poller;
struct spdk_io_channel *io_channel;
struct spdk_poller *stop_poller;
};
/* forward declaration */
static const struct spdk_vhost_dev_backend vhost_blk_device_backend;
static int
process_blk_request(struct spdk_vhost_blk_task *task,
struct spdk_vhost_blk_session *bvsession,
struct spdk_vhost_virtqueue *vq);
static void
blk_task_finish(struct spdk_vhost_blk_task *task)
{
assert(task->bvsession->vsession.task_cnt > 0);
task->bvsession->vsession.task_cnt--;
task->used = false;
}
static void
invalid_blk_request(struct spdk_vhost_blk_task *task, uint8_t status)
{
if (task->status) {
*task->status = status;
}
vhost_vq_used_ring_enqueue(&task->bvsession->vsession, task->vq, task->req_idx,
task->used_len);
blk_task_finish(task);
SPDK_DEBUGLOG(SPDK_LOG_VHOST_BLK_DATA, "Invalid request (status=%" PRIu8")\n", status);
}
/*
* Process task's descriptor chain and setup data related fields.
* Return
* total size of suplied buffers
*
* FIXME: Make this function return to rd_cnt and wr_cnt
*/
static int
blk_iovs_setup(struct spdk_vhost_blk_session *bvsession, struct spdk_vhost_virtqueue *vq,
uint16_t req_idx, struct iovec *iovs, uint16_t *iovs_cnt, uint32_t *length)
{
struct spdk_vhost_session *vsession = &bvsession->vsession;
struct spdk_vhost_dev *vdev = vsession->vdev;
struct vring_desc *desc, *desc_table;
uint16_t out_cnt = 0, cnt = 0;
uint32_t desc_table_size, len = 0;
uint32_t desc_handled_cnt;
int rc;
rc = vhost_vq_get_desc(vsession, vq, req_idx, &desc, &desc_table, &desc_table_size);
if (rc != 0) {
SPDK_ERRLOG("%s: invalid descriptor at index %"PRIu16".\n", vdev->name, req_idx);
return -1;
}
desc_handled_cnt = 0;
while (1) {
/*
* Maximum cnt reached?
* Should not happen if request is well formatted, otherwise this is a BUG.
*/
if (spdk_unlikely(cnt == *iovs_cnt)) {
SPDK_DEBUGLOG(SPDK_LOG_VHOST_BLK, "%s: max IOVs in request reached (req_idx = %"PRIu16").\n",
vsession->name, req_idx);
return -1;
}
if (spdk_unlikely(vhost_vring_desc_to_iov(vsession, iovs, &cnt, desc))) {
SPDK_DEBUGLOG(SPDK_LOG_VHOST_BLK, "%s: invalid descriptor %" PRIu16" (req_idx = %"PRIu16").\n",
vsession->name, req_idx, cnt);
return -1;
}
len += desc->len;
out_cnt += vhost_vring_desc_is_wr(desc);
rc = vhost_vring_desc_get_next(&desc, desc_table, desc_table_size);
if (rc != 0) {
SPDK_ERRLOG("%s: descriptor chain at index %"PRIu16" terminated unexpectedly.\n",
vsession->name, req_idx);
return -1;
} else if (desc == NULL) {
break;
}
desc_handled_cnt++;
if (spdk_unlikely(desc_handled_cnt > desc_table_size)) {
/* Break a cycle and report an error, if any. */
SPDK_ERRLOG("%s: found a cycle in the descriptor chain: desc_table_size = %d, desc_handled_cnt = %d.\n",
vsession->name, desc_table_size, desc_handled_cnt);
return -1;
}
}
/*
* There must be least two descriptors.
* First contain request so it must be readable.
* Last descriptor contain buffer for response so it must be writable.
*/
if (spdk_unlikely(out_cnt == 0 || cnt < 2)) {
return -1;
}
*length = len;
*iovs_cnt = cnt;
return 0;
}
static void
blk_request_finish(bool success, struct spdk_vhost_blk_task *task)
{
*task->status = success ? VIRTIO_BLK_S_OK : VIRTIO_BLK_S_IOERR;
vhost_vq_used_ring_enqueue(&task->bvsession->vsession, task->vq, task->req_idx,
task->used_len);
SPDK_DEBUGLOG(SPDK_LOG_VHOST_BLK, "Finished task (%p) req_idx=%d\n status: %s\n", task,
task->req_idx, success ? "OK" : "FAIL");
blk_task_finish(task);
}
static void
blk_request_complete_cb(struct spdk_bdev_io *bdev_io, bool success, void *cb_arg)
{
struct spdk_vhost_blk_task *task = cb_arg;
spdk_bdev_free_io(bdev_io);
blk_request_finish(success, task);
}
static void
blk_request_resubmit(void *arg)
{
struct spdk_vhost_blk_task *task = (struct spdk_vhost_blk_task *)arg;
int rc = 0;
rc = process_blk_request(task, task->bvsession, task->vq);
if (rc == 0) {
SPDK_DEBUGLOG(SPDK_LOG_VHOST_BLK, "====== Task %p resubmitted ======\n", task);
} else {
SPDK_DEBUGLOG(SPDK_LOG_VHOST_BLK, "====== Task %p failed ======\n", task);
}
}
static inline void
blk_request_queue_io(struct spdk_vhost_blk_task *task)
{
int rc;
struct spdk_vhost_blk_session *bvsession = task->bvsession;
struct spdk_bdev *bdev = bvsession->bvdev->bdev;
task->bdev_io_wait.bdev = bdev;
task->bdev_io_wait.cb_fn = blk_request_resubmit;
task->bdev_io_wait.cb_arg = task;
rc = spdk_bdev_queue_io_wait(bdev, bvsession->io_channel, &task->bdev_io_wait);
if (rc != 0) {
SPDK_ERRLOG("%s: failed to queue I/O, rc=%d\n", bvsession->vsession.name, rc);
invalid_blk_request(task, VIRTIO_BLK_S_IOERR);
}
}
static int
process_blk_request(struct spdk_vhost_blk_task *task,
struct spdk_vhost_blk_session *bvsession,
struct spdk_vhost_virtqueue *vq)
{
struct spdk_vhost_blk_dev *bvdev = bvsession->bvdev;
const struct virtio_blk_outhdr *req;
struct virtio_blk_discard_write_zeroes *desc;
struct iovec *iov;
uint32_t type;
uint32_t payload_len;
uint64_t flush_bytes;
int rc;
if (blk_iovs_setup(bvsession, vq, task->req_idx, task->iovs, &task->iovcnt, &payload_len)) {
SPDK_DEBUGLOG(SPDK_LOG_VHOST_BLK, "Invalid request (req_idx = %"PRIu16").\n", task->req_idx);
/* Only READ and WRITE are supported for now. */
invalid_blk_request(task, VIRTIO_BLK_S_UNSUPP);
return -1;
}
iov = &task->iovs[0];
if (spdk_unlikely(iov->iov_len != sizeof(*req))) {
SPDK_DEBUGLOG(SPDK_LOG_VHOST_BLK,
"First descriptor size is %zu but expected %zu (req_idx = %"PRIu16").\n",
iov->iov_len, sizeof(*req), task->req_idx);
invalid_blk_request(task, VIRTIO_BLK_S_UNSUPP);
return -1;
}
req = iov->iov_base;
iov = &task->iovs[task->iovcnt - 1];
if (spdk_unlikely(iov->iov_len != 1)) {
SPDK_DEBUGLOG(SPDK_LOG_VHOST_BLK,
"Last descriptor size is %zu but expected %d (req_idx = %"PRIu16").\n",
iov->iov_len, 1, task->req_idx);
invalid_blk_request(task, VIRTIO_BLK_S_UNSUPP);
return -1;
}
task->status = iov->iov_base;
payload_len -= sizeof(*req) + sizeof(*task->status);
task->iovcnt -= 2;
type = req->type;
#ifdef VIRTIO_BLK_T_BARRIER
/* Don't care about barier for now (as QEMU's virtio-blk do). */
type &= ~VIRTIO_BLK_T_BARRIER;
#endif
switch (type) {
case VIRTIO_BLK_T_IN:
case VIRTIO_BLK_T_OUT:
if (spdk_unlikely(payload_len == 0 || (payload_len & (512 - 1)) != 0)) {
SPDK_ERRLOG("%s - passed IO buffer is not multiple of 512b (req_idx = %"PRIu16").\n",
type ? "WRITE" : "READ", task->req_idx);
invalid_blk_request(task, VIRTIO_BLK_S_UNSUPP);
return -1;
}
if (type == VIRTIO_BLK_T_IN) {
task->used_len = payload_len + sizeof(*task->status);
rc = spdk_bdev_readv(bvdev->bdev_desc, bvsession->io_channel,
&task->iovs[1], task->iovcnt, req->sector * 512,
payload_len, blk_request_complete_cb, task);
} else if (!bvdev->readonly) {
task->used_len = sizeof(*task->status);
rc = spdk_bdev_writev(bvdev->bdev_desc, bvsession->io_channel,
&task->iovs[1], task->iovcnt, req->sector * 512,
payload_len, blk_request_complete_cb, task);
} else {
SPDK_DEBUGLOG(SPDK_LOG_VHOST_BLK, "Device is in read-only mode!\n");
rc = -1;
}
if (rc) {
if (rc == -ENOMEM) {
SPDK_DEBUGLOG(SPDK_LOG_VHOST_BLK, "No memory, start to queue io.\n");
blk_request_queue_io(task);
} else {
invalid_blk_request(task, VIRTIO_BLK_S_IOERR);
return -1;
}
}
break;
case VIRTIO_BLK_T_DISCARD:
desc = task->iovs[1].iov_base;
if (payload_len != sizeof(*desc)) {
SPDK_NOTICELOG("Invalid discard payload size: %u\n", payload_len);
invalid_blk_request(task, VIRTIO_BLK_S_IOERR);
return -1;
}
rc = spdk_bdev_unmap(bvdev->bdev_desc, bvsession->io_channel,
desc->sector * 512, desc->num_sectors * 512,
blk_request_complete_cb, task);
if (rc) {
if (rc == -ENOMEM) {
SPDK_DEBUGLOG(SPDK_LOG_VHOST_BLK, "No memory, start to queue io.\n");
blk_request_queue_io(task);
} else {
invalid_blk_request(task, VIRTIO_BLK_S_IOERR);
return -1;
}
}
break;
case VIRTIO_BLK_T_WRITE_ZEROES:
desc = task->iovs[1].iov_base;
if (payload_len != sizeof(*desc)) {
SPDK_NOTICELOG("Invalid write zeroes payload size: %u\n", payload_len);
invalid_blk_request(task, VIRTIO_BLK_S_IOERR);
return -1;
}
/* Zeroed and Unmap the range, SPDK doen't support it. */
if (desc->flags & VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP) {
SPDK_NOTICELOG("Can't support Write Zeroes with Unmap flag\n");
invalid_blk_request(task, VIRTIO_BLK_S_UNSUPP);
return -1;
}
rc = spdk_bdev_write_zeroes(bvdev->bdev_desc, bvsession->io_channel,
desc->sector * 512, desc->num_sectors * 512,
blk_request_complete_cb, task);
if (rc) {
if (rc == -ENOMEM) {
SPDK_DEBUGLOG(SPDK_LOG_VHOST_BLK, "No memory, start to queue io.\n");
blk_request_queue_io(task);
} else {
invalid_blk_request(task, VIRTIO_BLK_S_IOERR);
return -1;
}
}
break;
case VIRTIO_BLK_T_FLUSH:
flush_bytes = spdk_bdev_get_num_blocks(bvdev->bdev) * spdk_bdev_get_block_size(bvdev->bdev);
if (req->sector != 0) {
SPDK_NOTICELOG("sector must be zero for flush command\n");
invalid_blk_request(task, VIRTIO_BLK_S_IOERR);
return -1;
}
rc = spdk_bdev_flush(bvdev->bdev_desc, bvsession->io_channel,
0, flush_bytes,
blk_request_complete_cb, task);
if (rc) {
if (rc == -ENOMEM) {
SPDK_DEBUGLOG(SPDK_LOG_VHOST_BLK, "No memory, start to queue io.\n");
blk_request_queue_io(task);
} else {
invalid_blk_request(task, VIRTIO_BLK_S_IOERR);
return -1;
}
}
break;
case VIRTIO_BLK_T_GET_ID:
if (!task->iovcnt || !payload_len) {
invalid_blk_request(task, VIRTIO_BLK_S_UNSUPP);
return -1;
}
task->used_len = spdk_min((size_t)VIRTIO_BLK_ID_BYTES, task->iovs[1].iov_len);
spdk_strcpy_pad(task->iovs[1].iov_base, spdk_bdev_get_product_name(bvdev->bdev),
task->used_len, ' ');
blk_request_finish(true, task);
break;
default:
SPDK_DEBUGLOG(SPDK_LOG_VHOST_BLK, "Not supported request type '%"PRIu32"'.\n", type);
invalid_blk_request(task, VIRTIO_BLK_S_UNSUPP);
return -1;
}
return 0;
}
static void
process_vq(struct spdk_vhost_blk_session *bvsession, struct spdk_vhost_virtqueue *vq)
{
struct spdk_vhost_blk_task *task;
struct spdk_vhost_session *vsession = &bvsession->vsession;
int rc;
uint16_t reqs[32];
uint16_t reqs_cnt, i;
reqs_cnt = vhost_vq_avail_ring_get(vq, reqs, SPDK_COUNTOF(reqs));
if (!reqs_cnt) {
return;
}
for (i = 0; i < reqs_cnt; i++) {
SPDK_DEBUGLOG(SPDK_LOG_VHOST_BLK, "====== Starting processing request idx %"PRIu16"======\n",
reqs[i]);
if (spdk_unlikely(reqs[i] >= vq->vring.size)) {
SPDK_ERRLOG("%s: request idx '%"PRIu16"' exceeds virtqueue size (%"PRIu16").\n",
vsession->name, reqs[i], vq->vring.size);
vhost_vq_used_ring_enqueue(vsession, vq, reqs[i], 0);
continue;
}
task = &((struct spdk_vhost_blk_task *)vq->tasks)[reqs[i]];
if (spdk_unlikely(task->used)) {
SPDK_ERRLOG("%s: request with idx '%"PRIu16"' is already pending.\n",
vsession->name, reqs[i]);
vhost_vq_used_ring_enqueue(vsession, vq, reqs[i], 0);
continue;
}
vsession->task_cnt++;
task->used = true;
task->iovcnt = SPDK_COUNTOF(task->iovs);
task->status = NULL;
task->used_len = 0;
rc = process_blk_request(task, bvsession, vq);
if (rc == 0) {
SPDK_DEBUGLOG(SPDK_LOG_VHOST_BLK, "====== Task %p req_idx %d submitted ======\n", task,
reqs[i]);
} else {
SPDK_DEBUGLOG(SPDK_LOG_VHOST_BLK, "====== Task %p req_idx %d failed ======\n", task, reqs[i]);
}
}
}
static int
vdev_worker(void *arg)
{
struct spdk_vhost_blk_session *bvsession = arg;
struct spdk_vhost_session *vsession = &bvsession->vsession;
uint16_t q_idx;
for (q_idx = 0; q_idx < vsession->max_queues; q_idx++) {
process_vq(bvsession, &vsession->virtqueue[q_idx]);
}
vhost_session_used_signal(vsession);
return -1;
}
static void
no_bdev_process_vq(struct spdk_vhost_blk_session *bvsession, struct spdk_vhost_virtqueue *vq)
{
struct spdk_vhost_session *vsession = &bvsession->vsession;
struct iovec iovs[SPDK_VHOST_IOVS_MAX];
uint32_t length;
uint16_t iovcnt, req_idx;
if (vhost_vq_avail_ring_get(vq, &req_idx, 1) != 1) {
return;
}
iovcnt = SPDK_COUNTOF(iovs);
if (blk_iovs_setup(bvsession, vq, req_idx, iovs, &iovcnt, &length) == 0) {
*(volatile uint8_t *)iovs[iovcnt - 1].iov_base = VIRTIO_BLK_S_IOERR;
SPDK_DEBUGLOG(SPDK_LOG_VHOST_BLK_DATA, "Aborting request %" PRIu16"\n", req_idx);
}
vhost_vq_used_ring_enqueue(vsession, vq, req_idx, 0);
}
static int
no_bdev_vdev_worker(void *arg)
{
struct spdk_vhost_blk_session *bvsession = arg;
struct spdk_vhost_session *vsession = &bvsession->vsession;
uint16_t q_idx;
for (q_idx = 0; q_idx < vsession->max_queues; q_idx++) {
no_bdev_process_vq(bvsession, &vsession->virtqueue[q_idx]);
}
vhost_session_used_signal(vsession);
if (vsession->task_cnt == 0 && bvsession->io_channel) {
spdk_put_io_channel(bvsession->io_channel);
bvsession->io_channel = NULL;
}
return -1;
}
static struct spdk_vhost_blk_session *
to_blk_session(struct spdk_vhost_session *vsession)
{
assert(vsession->vdev->backend == &vhost_blk_device_backend);
return (struct spdk_vhost_blk_session *)vsession;
}
static struct spdk_vhost_blk_dev *
to_blk_dev(struct spdk_vhost_dev *vdev)
{
if (vdev == NULL) {
return NULL;
}
if (vdev->backend != &vhost_blk_device_backend) {
SPDK_ERRLOG("%s: not a vhost-blk device\n", vdev->name);
return NULL;
}
return SPDK_CONTAINEROF(vdev, struct spdk_vhost_blk_dev, vdev);
}
struct spdk_bdev *
spdk_vhost_blk_get_dev(struct spdk_vhost_dev *vdev)
{
struct spdk_vhost_blk_dev *bvdev = to_blk_dev(vdev);
assert(bvdev != NULL);
return bvdev->bdev;
}
static void
vhost_dev_bdev_remove_cpl_cb(struct spdk_vhost_dev *vdev, void *ctx)
{
/* All sessions have been notified, time to close the bdev */
struct spdk_vhost_blk_dev *bvdev = to_blk_dev(vdev);
assert(bvdev != NULL);
spdk_bdev_close(bvdev->bdev_desc);
bvdev->bdev_desc = NULL;
bvdev->bdev = NULL;
}
static int
vhost_session_bdev_remove_cb(struct spdk_vhost_dev *vdev,
struct spdk_vhost_session *vsession,
void *ctx)
{
struct spdk_vhost_blk_session *bvsession;
bvsession = (struct spdk_vhost_blk_session *)vsession;
if (bvsession->requestq_poller) {
spdk_poller_unregister(&bvsession->requestq_poller);
bvsession->requestq_poller = spdk_poller_register(no_bdev_vdev_worker, bvsession, 0);
}
return 0;
}
static void
bdev_remove_cb(void *remove_ctx)
{
struct spdk_vhost_blk_dev *bvdev = remove_ctx;
SPDK_WARNLOG("%s: hot-removing bdev - all further requests will fail.\n",
bvdev->vdev.name);
spdk_vhost_lock();
vhost_dev_foreach_session(&bvdev->vdev, vhost_session_bdev_remove_cb,
vhost_dev_bdev_remove_cpl_cb, NULL);
spdk_vhost_unlock();
}
static void
free_task_pool(struct spdk_vhost_blk_session *bvsession)
{
struct spdk_vhost_session *vsession = &bvsession->vsession;
struct spdk_vhost_virtqueue *vq;
uint16_t i;
for (i = 0; i < vsession->max_queues; i++) {
vq = &vsession->virtqueue[i];
if (vq->tasks == NULL) {
continue;
}
spdk_free(vq->tasks);
vq->tasks = NULL;
}
}
static int
alloc_task_pool(struct spdk_vhost_blk_session *bvsession)
{
struct spdk_vhost_session *vsession = &bvsession->vsession;
struct spdk_vhost_virtqueue *vq;
struct spdk_vhost_blk_task *task;
uint32_t task_cnt;
uint16_t i;
uint32_t j;
for (i = 0; i < vsession->max_queues; i++) {
vq = &vsession->virtqueue[i];
if (vq->vring.desc == NULL) {
continue;
}
task_cnt = vq->vring.size;
if (task_cnt > SPDK_VHOST_MAX_VQ_SIZE) {
/* sanity check */
SPDK_ERRLOG("%s: virtuque %"PRIu16" is too big. (size = %"PRIu32", max = %"PRIu32")\n",
vsession->name, i, task_cnt, SPDK_VHOST_MAX_VQ_SIZE);
free_task_pool(bvsession);
return -1;
}
vq->tasks = spdk_zmalloc(sizeof(struct spdk_vhost_blk_task) * task_cnt,
SPDK_CACHE_LINE_SIZE, NULL,
SPDK_ENV_LCORE_ID_ANY, SPDK_MALLOC_DMA);
if (vq->tasks == NULL) {
SPDK_ERRLOG("%s: failed to allocate %"PRIu32" tasks for virtqueue %"PRIu16"\n",
vsession->name, task_cnt, i);
free_task_pool(bvsession);
return -1;
}
for (j = 0; j < task_cnt; j++) {
task = &((struct spdk_vhost_blk_task *)vq->tasks)[j];
task->bvsession = bvsession;
task->req_idx = j;
task->vq = vq;
}
}
return 0;
}
static int
vhost_blk_start_cb(struct spdk_vhost_dev *vdev,
struct spdk_vhost_session *vsession, void *unused)
{
struct spdk_vhost_blk_session *bvsession = to_blk_session(vsession);
struct spdk_vhost_blk_dev *bvdev;
int i, rc = 0;
bvdev = to_blk_dev(vdev);
assert(bvdev != NULL);
bvsession->bvdev = bvdev;
/* validate all I/O queues are in a contiguous index range */
for (i = 0; i < vsession->max_queues; i++) {
if (vsession->virtqueue[i].vring.desc == NULL) {
SPDK_ERRLOG("%s: queue %"PRIu32" is empty\n", vsession->name, i);
rc = -1;
goto out;
}
}
rc = alloc_task_pool(bvsession);
if (rc != 0) {
SPDK_ERRLOG("%s: failed to alloc task pool.\n", vsession->name);
goto out;
}
if (bvdev->bdev) {
bvsession->io_channel = spdk_bdev_get_io_channel(bvdev->bdev_desc);
if (!bvsession->io_channel) {
free_task_pool(bvsession);
SPDK_ERRLOG("%s: I/O channel allocation failed\n", vsession->name);
rc = -1;
goto out;
}
}
bvsession->requestq_poller = spdk_poller_register(bvdev->bdev ? vdev_worker : no_bdev_vdev_worker,
bvsession, 0);
SPDK_INFOLOG(SPDK_LOG_VHOST, "%s: started poller on lcore %d\n",
vsession->name, spdk_env_get_current_core());
out:
vhost_session_start_done(vsession, rc);
return rc;
}
static int
vhost_blk_start(struct spdk_vhost_session *vsession)
{
struct vhost_poll_group *pg;
pg = vhost_get_poll_group(vsession->vdev->cpumask);
return vhost_session_send_event(pg, vsession, vhost_blk_start_cb,
3, "start session");
}
static int
destroy_session_poller_cb(void *arg)
{
struct spdk_vhost_blk_session *bvsession = arg;
struct spdk_vhost_session *vsession = &bvsession->vsession;
int i;
if (vsession->task_cnt > 0) {
return -1;
}
if (spdk_vhost_trylock() != 0) {
return -1;
}
for (i = 0; i < vsession->max_queues; i++) {
vsession->virtqueue[i].next_event_time = 0;
vhost_vq_used_signal(vsession, &vsession->virtqueue[i]);
}
SPDK_INFOLOG(SPDK_LOG_VHOST, "%s: stopping poller on lcore %d\n",
vsession->name, spdk_env_get_current_core());
if (bvsession->io_channel) {
spdk_put_io_channel(bvsession->io_channel);
bvsession->io_channel = NULL;
}
free_task_pool(bvsession);
spdk_poller_unregister(&bvsession->stop_poller);
vhost_session_stop_done(vsession, 0);
spdk_vhost_unlock();
return -1;
}
static int
vhost_blk_stop_cb(struct spdk_vhost_dev *vdev,
struct spdk_vhost_session *vsession, void *unused)
{
struct spdk_vhost_blk_session *bvsession = to_blk_session(vsession);
spdk_poller_unregister(&bvsession->requestq_poller);
bvsession->stop_poller = spdk_poller_register(destroy_session_poller_cb,
bvsession, 1000);
return 0;
}
static int
vhost_blk_stop(struct spdk_vhost_session *vsession)
{
return vhost_session_send_event(vsession->poll_group, vsession,
vhost_blk_stop_cb, 3, "stop session");
}
static void
vhost_blk_dump_info_json(struct spdk_vhost_dev *vdev, struct spdk_json_write_ctx *w)
{
struct spdk_bdev *bdev = spdk_vhost_blk_get_dev(vdev);
struct spdk_vhost_blk_dev *bvdev;
bvdev = to_blk_dev(vdev);
assert(bvdev != NULL);
spdk_json_write_named_object_begin(w, "block");
spdk_json_write_named_bool(w, "readonly", bvdev->readonly);
spdk_json_write_name(w, "bdev");
if (bdev) {
spdk_json_write_string(w, spdk_bdev_get_name(bdev));
} else {
spdk_json_write_null(w);
}
spdk_json_write_object_end(w);
}
static void
vhost_blk_write_config_json(struct spdk_vhost_dev *vdev, struct spdk_json_write_ctx *w)
{
struct spdk_vhost_blk_dev *bvdev;
bvdev = to_blk_dev(vdev);
assert(bvdev != NULL);
if (!bvdev->bdev) {
return;
}
spdk_json_write_object_begin(w);
spdk_json_write_named_string(w, "method", "construct_vhost_blk_controller");
spdk_json_write_named_object_begin(w, "params");
spdk_json_write_named_string(w, "ctrlr", vdev->name);
spdk_json_write_named_string(w, "dev_name", spdk_bdev_get_name(bvdev->bdev));
spdk_json_write_named_string(w, "cpumask", spdk_cpuset_fmt(vdev->cpumask));
spdk_json_write_named_bool(w, "readonly", bvdev->readonly);
spdk_json_write_object_end(w);
spdk_json_write_object_end(w);
}
static int vhost_blk_destroy(struct spdk_vhost_dev *dev);
static int
vhost_blk_get_config(struct spdk_vhost_dev *vdev, uint8_t *config,
uint32_t len)
{
struct virtio_blk_config blkcfg;
struct spdk_vhost_blk_dev *bvdev;
struct spdk_bdev *bdev;
uint32_t blk_size;
uint64_t blkcnt;
bvdev = to_blk_dev(vdev);
assert(bvdev != NULL);
bdev = bvdev->bdev;
if (bdev == NULL) {
/* We can't just return -1 here as this GET_CONFIG message might
* be caused by a QEMU VM reboot. Returning -1 will indicate an
* error to QEMU, who might then decide to terminate itself.
* We don't want that. A simple reboot shouldn't break the system.
*
* Presenting a block device with block size 0 and block count 0
* doesn't cause any problems on QEMU side and the virtio-pci
* device is even still available inside the VM, but there will
* be no block device created for it - the kernel drivers will
* silently reject it.
*/
blk_size = 0;
blkcnt = 0;
} else {
blk_size = spdk_bdev_get_block_size(bdev);
blkcnt = spdk_bdev_get_num_blocks(bdev);
if (spdk_bdev_get_buf_align(bdev) > 1) {
blkcfg.size_max = SPDK_BDEV_LARGE_BUF_MAX_SIZE;
blkcfg.seg_max = spdk_min(SPDK_VHOST_IOVS_MAX - 2 - 1, BDEV_IO_NUM_CHILD_IOV - 2 - 1);
} else {
blkcfg.size_max = 131072;
/* -2 for REQ and RESP and -1 for region boundary splitting */
blkcfg.seg_max = SPDK_VHOST_IOVS_MAX - 2 - 1;
}
}
memset(&blkcfg, 0, sizeof(blkcfg));
blkcfg.blk_size = blk_size;
/* minimum I/O size in blocks */
blkcfg.min_io_size = 1;
/* expressed in 512 Bytes sectors */
blkcfg.capacity = (blkcnt * blk_size) / 512;
/* QEMU can overwrite this value when started */
blkcfg.num_queues = SPDK_VHOST_MAX_VQUEUES;
if (bdev && spdk_bdev_io_type_supported(bdev, SPDK_BDEV_IO_TYPE_UNMAP)) {
/* 16MiB, expressed in 512 Bytes */
blkcfg.max_discard_sectors = 32768;
blkcfg.max_discard_seg = 1;
blkcfg.discard_sector_alignment = blk_size / 512;
}
if (bdev && spdk_bdev_io_type_supported(bdev, SPDK_BDEV_IO_TYPE_WRITE_ZEROES)) {
blkcfg.max_write_zeroes_sectors = 32768;
blkcfg.max_write_zeroes_seg = 1;
}
memcpy(config, &blkcfg, spdk_min(len, sizeof(blkcfg)));
return 0;
}
static const struct spdk_vhost_dev_backend vhost_blk_device_backend = {
.virtio_features = SPDK_VHOST_FEATURES |
(1ULL << VIRTIO_BLK_F_SIZE_MAX) | (1ULL << VIRTIO_BLK_F_SEG_MAX) |
(1ULL << VIRTIO_BLK_F_GEOMETRY) | (1ULL << VIRTIO_BLK_F_RO) |
(1ULL << VIRTIO_BLK_F_BLK_SIZE) | (1ULL << VIRTIO_BLK_F_TOPOLOGY) |
(1ULL << VIRTIO_BLK_F_BARRIER) | (1ULL << VIRTIO_BLK_F_SCSI) |
(1ULL << VIRTIO_BLK_F_FLUSH) | (1ULL << VIRTIO_BLK_F_CONFIG_WCE) |
(1ULL << VIRTIO_BLK_F_MQ) | (1ULL << VIRTIO_BLK_F_DISCARD) |
(1ULL << VIRTIO_BLK_F_WRITE_ZEROES),
.disabled_features = SPDK_VHOST_DISABLED_FEATURES | (1ULL << VIRTIO_BLK_F_GEOMETRY) |
(1ULL << VIRTIO_BLK_F_RO) | (1ULL << VIRTIO_BLK_F_FLUSH) | (1ULL << VIRTIO_BLK_F_CONFIG_WCE) |
(1ULL << VIRTIO_BLK_F_BARRIER) | (1ULL << VIRTIO_BLK_F_SCSI) | (1ULL << VIRTIO_BLK_F_DISCARD) |
(1ULL << VIRTIO_BLK_F_WRITE_ZEROES),
.session_ctx_size = sizeof(struct spdk_vhost_blk_session) - sizeof(struct spdk_vhost_session),
.start_session = vhost_blk_start,
.stop_session = vhost_blk_stop,
.vhost_get_config = vhost_blk_get_config,
.dump_info_json = vhost_blk_dump_info_json,
.write_config_json = vhost_blk_write_config_json,
.remove_device = vhost_blk_destroy,
};
int
vhost_blk_controller_construct(void)
{
struct spdk_conf_section *sp;
unsigned ctrlr_num;
char *bdev_name;
char *cpumask;
char *name;
bool readonly;
for (sp = spdk_conf_first_section(NULL); sp != NULL; sp = spdk_conf_next_section(sp)) {
if (!spdk_conf_section_match_prefix(sp, "VhostBlk")) {
continue;
}
if (sscanf(spdk_conf_section_get_name(sp), "VhostBlk%u", &ctrlr_num) != 1) {
SPDK_ERRLOG("Section '%s' has non-numeric suffix.\n",
spdk_conf_section_get_name(sp));
return -1;
}
name = spdk_conf_section_get_val(sp, "Name");
if (name == NULL) {
SPDK_ERRLOG("VhostBlk%u: missing Name\n", ctrlr_num);
return -1;
}
cpumask = spdk_conf_section_get_val(sp, "Cpumask");
readonly = spdk_conf_section_get_boolval(sp, "ReadOnly", false);
bdev_name = spdk_conf_section_get_val(sp, "Dev");
if (bdev_name == NULL) {
continue;
}
if (spdk_vhost_blk_construct(name, cpumask, bdev_name, readonly) < 0) {
return -1;
}
}
return 0;
}
int
spdk_vhost_blk_construct(const char *name, const char *cpumask, const char *dev_name, bool readonly)
{
struct spdk_vhost_blk_dev *bvdev = NULL;
struct spdk_bdev *bdev;
uint64_t features = 0;
int ret = 0;
spdk_vhost_lock();
bdev = spdk_bdev_get_by_name(dev_name);
if (bdev == NULL) {
SPDK_ERRLOG("%s: bdev '%s' not found\n",
name, dev_name);
ret = -ENODEV;
goto out;
}
bvdev = calloc(1, sizeof(*bvdev));
if (bvdev == NULL) {
ret = -ENOMEM;
goto out;
}
ret = spdk_bdev_open(bdev, true, bdev_remove_cb, bvdev, &bvdev->bdev_desc);
if (ret != 0) {
SPDK_ERRLOG("%s: could not open bdev '%s', error=%d\n",
name, dev_name, ret);
goto out;
}
bvdev->bdev = bdev;
bvdev->readonly = readonly;
ret = vhost_dev_register(&bvdev->vdev, name, cpumask, &vhost_blk_device_backend);
if (ret != 0) {
spdk_bdev_close(bvdev->bdev_desc);
goto out;
}
if (spdk_bdev_io_type_supported(bdev, SPDK_BDEV_IO_TYPE_UNMAP)) {
features |= (1ULL << VIRTIO_BLK_F_DISCARD);
}
if (spdk_bdev_io_type_supported(bdev, SPDK_BDEV_IO_TYPE_WRITE_ZEROES)) {
features |= (1ULL << VIRTIO_BLK_F_WRITE_ZEROES);
}
if (readonly) {
features |= (1ULL << VIRTIO_BLK_F_RO);
}
if (spdk_bdev_io_type_supported(bdev, SPDK_BDEV_IO_TYPE_FLUSH)) {
features |= (1ULL << VIRTIO_BLK_F_FLUSH);
}
if (features && rte_vhost_driver_enable_features(bvdev->vdev.path, features)) {
SPDK_ERRLOG("%s: failed to enable features 0x%"PRIx64"\n", name, features);
if (vhost_dev_unregister(&bvdev->vdev) != 0) {
SPDK_ERRLOG("%s: failed to remove device\n", name);
}
spdk_bdev_close(bvdev->bdev_desc);
ret = -1;
goto out;
}
SPDK_INFOLOG(SPDK_LOG_VHOST, "%s: using bdev '%s'\n", name, dev_name);
out:
if (ret != 0 && bvdev) {
free(bvdev);
}
spdk_vhost_unlock();
return ret;
}
static int
vhost_blk_destroy(struct spdk_vhost_dev *vdev)
{
struct spdk_vhost_blk_dev *bvdev = to_blk_dev(vdev);
int rc;
assert(bvdev != NULL);
rc = vhost_dev_unregister(&bvdev->vdev);
if (rc != 0) {
return rc;
}
if (bvdev->bdev_desc) {
spdk_bdev_close(bvdev->bdev_desc);
bvdev->bdev_desc = NULL;
}
bvdev->bdev = NULL;
free(bvdev);
return 0;
}
SPDK_LOG_REGISTER_COMPONENT("vhost_blk", SPDK_LOG_VHOST_BLK)
SPDK_LOG_REGISTER_COMPONENT("vhost_blk_data", SPDK_LOG_VHOST_BLK_DATA)