Function vhost_user_set_log_base

dpdk/lib/vhost/vhost_user.c:2286–2382

}

static int
vhost_user_set_log_base(struct virtio_net **pdev,
			struct vhu_msg_context *ctx,
			int main_fd __rte_unused)
{
	struct virtio_net *dev = *pdev;
	int fd = ctx->fds[0];
	uint64_t size, off;
	uint64_t alignment;
	void *addr;
	uint32_t i;

	if (validate_msg_fds(dev, ctx, 1) != 0)
		return RTE_VHOST_MSG_RESULT_ERR;

	if (fd < 0) {
		VHOST_LOG_CONFIG(dev->ifname, ERR, "invalid log fd: %d\n", fd);
		return RTE_VHOST_MSG_RESULT_ERR;
	}

	if (ctx->msg.size != sizeof(VhostUserLog)) {
		VHOST_LOG_CONFIG(dev->ifname, ERR,
			"invalid log base msg size: %"PRId32" != %d\n",
			ctx->msg.size, (int)sizeof(VhostUserLog));
		goto close_msg_fds;
	}

	size = ctx->msg.payload.log.mmap_size;
	off  = ctx->msg.payload.log.mmap_offset;

	/* Check for mmap size and offset overflow. */
	if (off >= -size) {
		VHOST_LOG_CONFIG(dev->ifname, ERR,
			"log offset %#"PRIx64" and log size %#"PRIx64" overflow\n",
			off, size);
		goto close_msg_fds;
	}

	VHOST_LOG_CONFIG(dev->ifname, INFO,
		"log mmap size: %"PRId64", offset: %"PRId64"\n",
		size, off);

	/*
	 * mmap from 0 to workaround a hugepage mmap bug: mmap will
	 * fail when offset is not page size aligned.
	 */
	addr = mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, off);
	alignment = get_blk_size(fd);
	close(fd);
	if (addr == MAP_FAILED) {
		VHOST_LOG_CONFIG(dev->ifname, ERR, "mmap log base failed!\n");
		return RTE_VHOST_MSG_RESULT_ERR;
	}

	/*
	 * Free previously mapped log memory on occasionally
	 * multiple VHOST_USER_SET_LOG_BASE.
	 */