DPDK  20.11.3
examples/vhost_blk/blk.c
/* SPDX-License-Identifier: BSD-3-Clause
* Copyright(c) 2010-2019 Intel Corporation
*/
#include <stdio.h>
#include <stdint.h>
#include <unistd.h>
#include <assert.h>
#include <ctype.h>
#include <string.h>
#include <stddef.h>
#include <rte_atomic.h>
#include <rte_cycles.h>
#include <rte_log.h>
#include <rte_malloc.h>
#include <rte_byteorder.h>
#include <rte_string_fns.h>
#include "vhost_blk.h"
#include "blk_spec.h"
static void
vhost_strcpy_pad(void *dst, const char *src, size_t size, int pad)
{
size_t len;
len = strlen(src);
if (len < size) {
memcpy(dst, src, len);
memset((char *)dst + len, pad, size - len);
} else {
memcpy(dst, src, size);
}
}
static int
vhost_bdev_blk_readwrite(struct vhost_block_dev *bdev,
struct vhost_blk_task *task,
uint64_t lba_512, __rte_unused uint32_t xfer_len)
{
uint32_t i;
uint64_t offset;
uint32_t nbytes = 0;
offset = lba_512 * 512;
/* iovs[0] is the head and iovs[iovs_cnt - 1] is the tail
* Middle is the data range
*/
for (i = 1; i < task->iovs_cnt - 1; i++) {
if (task->dxfer_dir == BLK_DIR_TO_DEV)
memcpy(bdev->data + offset, task->iovs[i].iov_base,
task->iovs[i].iov_len);
else
memcpy(task->iovs[i].iov_base, bdev->data + offset,
task->iovs[i].iov_len);
offset += task->iovs[i].iov_len;
nbytes += task->iovs[i].iov_len;
}
return nbytes;
}
int
vhost_bdev_process_blk_commands(struct vhost_block_dev *bdev,
struct vhost_blk_task *task)
{
size_t used_len;
if (unlikely(task->data_len > (bdev->blockcnt * bdev->blocklen))) {
fprintf(stderr, "read or write beyond capacity\n");
return VIRTIO_BLK_S_UNSUPP;
}
switch (task->req->type) {
case VIRTIO_BLK_T_IN:
if (unlikely(task->data_len == 0 ||
(task->data_len & (512 - 1)) != 0)) {
fprintf(stderr,
"%s - passed IO buffer is not multiple of 512b"
"(req_idx = %"PRIu16").\n",
task->req->type ? "WRITE" : "READ",
task->req_idx);
return VIRTIO_BLK_S_UNSUPP;
}
task->dxfer_dir = BLK_DIR_FROM_DEV;
vhost_bdev_blk_readwrite(bdev, task,
task->req->sector, task->data_len);
break;
case VIRTIO_BLK_T_OUT:
if (unlikely(task->data_len == 0 ||
(task->data_len & (512 - 1)) != 0)) {
fprintf(stderr,
"%s - passed IO buffer is not multiple of 512b"
"(req_idx = %"PRIu16").\n",
task->req->type ? "WRITE" : "READ",
task->req_idx);
return VIRTIO_BLK_S_UNSUPP;
}
task->dxfer_dir = BLK_DIR_TO_DEV;
vhost_bdev_blk_readwrite(bdev, task,
task->req->sector, task->data_len);
break;
case VIRTIO_BLK_T_GET_ID:
if (!task->iovs_cnt || task->data_len)
return VIRTIO_BLK_S_UNSUPP;
used_len = RTE_MIN((size_t)VIRTIO_BLK_ID_BYTES, task->data_len);
vhost_strcpy_pad(task->iovs[0].iov_base,
bdev->product_name, used_len, ' ');
break;
default:
fprintf(stderr, "unsupported cmd\n");
return VIRTIO_BLK_S_UNSUPP;
}
return VIRTIO_BLK_S_OK;
}