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Diffstat (limited to 'drivers/net/virtio/virtio_user/vhost_kernel.c')
-rw-r--r--drivers/net/virtio/virtio_user/vhost_kernel.c403
1 files changed, 403 insertions, 0 deletions
diff --git a/drivers/net/virtio/virtio_user/vhost_kernel.c b/drivers/net/virtio/virtio_user/vhost_kernel.c
new file mode 100644
index 00000000..68d28b13
--- /dev/null
+++ b/drivers/net/virtio/virtio_user/vhost_kernel.c
@@ -0,0 +1,403 @@
+/*-
+ * BSD LICENSE
+ *
+ * Copyright(c) 2016 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 <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+#include <rte_memory.h>
+#include <rte_eal_memconfig.h>
+
+#include "vhost.h"
+#include "virtio_user_dev.h"
+#include "vhost_kernel_tap.h"
+
+struct vhost_memory_kernel {
+ uint32_t nregions;
+ uint32_t padding;
+ struct vhost_memory_region regions[0];
+};
+
+/* vhost kernel ioctls */
+#define VHOST_VIRTIO 0xAF
+#define VHOST_GET_FEATURES _IOR(VHOST_VIRTIO, 0x00, __u64)
+#define VHOST_SET_FEATURES _IOW(VHOST_VIRTIO, 0x00, __u64)
+#define VHOST_SET_OWNER _IO(VHOST_VIRTIO, 0x01)
+#define VHOST_RESET_OWNER _IO(VHOST_VIRTIO, 0x02)
+#define VHOST_SET_MEM_TABLE _IOW(VHOST_VIRTIO, 0x03, struct vhost_memory_kernel)
+#define VHOST_SET_LOG_BASE _IOW(VHOST_VIRTIO, 0x04, __u64)
+#define VHOST_SET_LOG_FD _IOW(VHOST_VIRTIO, 0x07, int)
+#define VHOST_SET_VRING_NUM _IOW(VHOST_VIRTIO, 0x10, struct vhost_vring_state)
+#define VHOST_SET_VRING_ADDR _IOW(VHOST_VIRTIO, 0x11, struct vhost_vring_addr)
+#define VHOST_SET_VRING_BASE _IOW(VHOST_VIRTIO, 0x12, struct vhost_vring_state)
+#define VHOST_GET_VRING_BASE _IOWR(VHOST_VIRTIO, 0x12, struct vhost_vring_state)
+#define VHOST_SET_VRING_KICK _IOW(VHOST_VIRTIO, 0x20, struct vhost_vring_file)
+#define VHOST_SET_VRING_CALL _IOW(VHOST_VIRTIO, 0x21, struct vhost_vring_file)
+#define VHOST_SET_VRING_ERR _IOW(VHOST_VIRTIO, 0x22, struct vhost_vring_file)
+#define VHOST_NET_SET_BACKEND _IOW(VHOST_VIRTIO, 0x30, struct vhost_vring_file)
+
+static uint64_t max_regions = 64;
+
+static void
+get_vhost_kernel_max_regions(void)
+{
+ int fd;
+ char buf[20] = {'\0'};
+
+ fd = open("/sys/module/vhost/parameters/max_mem_regions", O_RDONLY);
+ if (fd < 0)
+ return;
+
+ if (read(fd, buf, sizeof(buf) - 1) > 0)
+ max_regions = strtoull(buf, NULL, 10);
+
+ close(fd);
+}
+
+static uint64_t vhost_req_user_to_kernel[] = {
+ [VHOST_USER_SET_OWNER] = VHOST_SET_OWNER,
+ [VHOST_USER_RESET_OWNER] = VHOST_RESET_OWNER,
+ [VHOST_USER_SET_FEATURES] = VHOST_SET_FEATURES,
+ [VHOST_USER_GET_FEATURES] = VHOST_GET_FEATURES,
+ [VHOST_USER_SET_VRING_CALL] = VHOST_SET_VRING_CALL,
+ [VHOST_USER_SET_VRING_NUM] = VHOST_SET_VRING_NUM,
+ [VHOST_USER_SET_VRING_BASE] = VHOST_SET_VRING_BASE,
+ [VHOST_USER_GET_VRING_BASE] = VHOST_GET_VRING_BASE,
+ [VHOST_USER_SET_VRING_ADDR] = VHOST_SET_VRING_ADDR,
+ [VHOST_USER_SET_VRING_KICK] = VHOST_SET_VRING_KICK,
+ [VHOST_USER_SET_MEM_TABLE] = VHOST_SET_MEM_TABLE,
+};
+
+/* By default, vhost kernel module allows 64 regions, but DPDK allows
+ * 256 segments. As a relief, below function merges those virtually
+ * adjacent memsegs into one region.
+ */
+static struct vhost_memory_kernel *
+prepare_vhost_memory_kernel(void)
+{
+ uint32_t i, j, k = 0;
+ struct rte_memseg *seg;
+ struct vhost_memory_region *mr;
+ struct vhost_memory_kernel *vm;
+
+ vm = malloc(sizeof(struct vhost_memory_kernel) +
+ max_regions *
+ sizeof(struct vhost_memory_region));
+ if (!vm)
+ return NULL;
+
+ for (i = 0; i < RTE_MAX_MEMSEG; ++i) {
+ seg = &rte_eal_get_configuration()->mem_config->memseg[i];
+ if (!seg->addr)
+ break;
+
+ int new_region = 1;
+
+ for (j = 0; j < k; ++j) {
+ mr = &vm->regions[j];
+
+ if (mr->userspace_addr + mr->memory_size ==
+ (uint64_t)(uintptr_t)seg->addr) {
+ mr->memory_size += seg->len;
+ new_region = 0;
+ break;
+ }
+
+ if ((uint64_t)(uintptr_t)seg->addr + seg->len ==
+ mr->userspace_addr) {
+ mr->guest_phys_addr =
+ (uint64_t)(uintptr_t)seg->addr;
+ mr->userspace_addr =
+ (uint64_t)(uintptr_t)seg->addr;
+ mr->memory_size += seg->len;
+ new_region = 0;
+ break;
+ }
+ }
+
+ if (new_region == 0)
+ continue;
+
+ mr = &vm->regions[k++];
+ /* use vaddr here! */
+ mr->guest_phys_addr = (uint64_t)(uintptr_t)seg->addr;
+ mr->userspace_addr = (uint64_t)(uintptr_t)seg->addr;
+ mr->memory_size = seg->len;
+ mr->mmap_offset = 0;
+
+ if (k >= max_regions) {
+ free(vm);
+ return NULL;
+ }
+ }
+
+ vm->nregions = k;
+ vm->padding = 0;
+ return vm;
+}
+
+/* with below features, vhost kernel does not need to do the checksum and TSO,
+ * these info will be passed to virtio_user through virtio net header.
+ */
+#define VHOST_KERNEL_GUEST_OFFLOADS_MASK \
+ ((1ULL << VIRTIO_NET_F_GUEST_CSUM) | \
+ (1ULL << VIRTIO_NET_F_GUEST_TSO4) | \
+ (1ULL << VIRTIO_NET_F_GUEST_TSO6) | \
+ (1ULL << VIRTIO_NET_F_GUEST_ECN) | \
+ (1ULL << VIRTIO_NET_F_GUEST_UFO))
+
+/* with below features, when flows from virtio_user to vhost kernel
+ * (1) if flows goes up through the kernel networking stack, it does not need
+ * to verify checksum, which can save CPU cycles;
+ * (2) if flows goes through a Linux bridge and outside from an interface
+ * (kernel driver), checksum and TSO will be done by GSO in kernel or even
+ * offloaded into real physical device.
+ */
+#define VHOST_KERNEL_HOST_OFFLOADS_MASK \
+ ((1ULL << VIRTIO_NET_F_HOST_TSO4) | \
+ (1ULL << VIRTIO_NET_F_HOST_TSO6) | \
+ (1ULL << VIRTIO_NET_F_CSUM))
+
+static int
+tap_supporte_mq(void)
+{
+ int tapfd;
+ unsigned int tap_features;
+
+ tapfd = open(PATH_NET_TUN, O_RDWR);
+ if (tapfd < 0) {
+ PMD_DRV_LOG(ERR, "fail to open %s: %s",
+ PATH_NET_TUN, strerror(errno));
+ return -1;
+ }
+
+ if (ioctl(tapfd, TUNGETFEATURES, &tap_features) == -1) {
+ PMD_DRV_LOG(ERR, "TUNGETFEATURES failed: %s", strerror(errno));
+ close(tapfd);
+ return -1;
+ }
+
+ close(tapfd);
+ return tap_features & IFF_MULTI_QUEUE;
+}
+
+static int
+vhost_kernel_ioctl(struct virtio_user_dev *dev,
+ enum vhost_user_request req,
+ void *arg)
+{
+ int ret = -1;
+ unsigned int i;
+ uint64_t req_kernel;
+ struct vhost_memory_kernel *vm = NULL;
+ int vhostfd;
+ unsigned int queue_sel;
+
+ PMD_DRV_LOG(INFO, "%s", vhost_msg_strings[req]);
+
+ req_kernel = vhost_req_user_to_kernel[req];
+
+ if (req_kernel == VHOST_SET_MEM_TABLE) {
+ vm = prepare_vhost_memory_kernel();
+ if (!vm)
+ return -1;
+ arg = (void *)vm;
+ }
+
+ if (req_kernel == VHOST_SET_FEATURES) {
+ /* We don't need memory protection here */
+ *(uint64_t *)arg &= ~(1ULL << VIRTIO_F_IOMMU_PLATFORM);
+
+ /* VHOST kernel does not know about below flags */
+ *(uint64_t *)arg &= ~VHOST_KERNEL_GUEST_OFFLOADS_MASK;
+ *(uint64_t *)arg &= ~VHOST_KERNEL_HOST_OFFLOADS_MASK;
+
+ *(uint64_t *)arg &= ~(1ULL << VIRTIO_NET_F_MQ);
+ }
+
+ switch (req_kernel) {
+ case VHOST_SET_VRING_NUM:
+ case VHOST_SET_VRING_ADDR:
+ case VHOST_SET_VRING_BASE:
+ case VHOST_GET_VRING_BASE:
+ case VHOST_SET_VRING_KICK:
+ case VHOST_SET_VRING_CALL:
+ queue_sel = *(unsigned int *)arg;
+ vhostfd = dev->vhostfds[queue_sel / 2];
+ *(unsigned int *)arg = queue_sel % 2;
+ PMD_DRV_LOG(DEBUG, "vhostfd=%d, index=%u",
+ vhostfd, *(unsigned int *)arg);
+ break;
+ default:
+ vhostfd = -1;
+ }
+ if (vhostfd == -1) {
+ for (i = 0; i < dev->max_queue_pairs; ++i) {
+ if (dev->vhostfds[i] < 0)
+ continue;
+
+ ret = ioctl(dev->vhostfds[i], req_kernel, arg);
+ if (ret < 0)
+ break;
+ }
+ } else {
+ ret = ioctl(vhostfd, req_kernel, arg);
+ }
+
+ if (!ret && req_kernel == VHOST_GET_FEATURES) {
+ /* with tap as the backend, all these features are supported
+ * but not claimed by vhost-net, so we add them back when
+ * reporting to upper layer.
+ */
+ *((uint64_t *)arg) |= VHOST_KERNEL_GUEST_OFFLOADS_MASK;
+ *((uint64_t *)arg) |= VHOST_KERNEL_HOST_OFFLOADS_MASK;
+
+ /* vhost_kernel will not declare this feature, but it does
+ * support multi-queue.
+ */
+ if (tap_supporte_mq())
+ *(uint64_t *)arg |= (1ull << VIRTIO_NET_F_MQ);
+ }
+
+ if (vm)
+ free(vm);
+
+ if (ret < 0)
+ PMD_DRV_LOG(ERR, "%s failed: %s",
+ vhost_msg_strings[req], strerror(errno));
+
+ return ret;
+}
+
+/**
+ * Set up environment to talk with a vhost kernel backend.
+ *
+ * @return
+ * - (-1) if fail to set up;
+ * - (>=0) if successful.
+ */
+static int
+vhost_kernel_setup(struct virtio_user_dev *dev)
+{
+ int vhostfd;
+ uint32_t i;
+
+ get_vhost_kernel_max_regions();
+
+ for (i = 0; i < dev->max_queue_pairs; ++i) {
+ vhostfd = open(dev->path, O_RDWR);
+ if (vhostfd < 0) {
+ PMD_DRV_LOG(ERR, "fail to open %s, %s",
+ dev->path, strerror(errno));
+ return -1;
+ }
+
+ dev->vhostfds[i] = vhostfd;
+ }
+
+ return 0;
+}
+
+static int
+vhost_kernel_set_backend(int vhostfd, int tapfd)
+{
+ struct vhost_vring_file f;
+
+ f.fd = tapfd;
+ f.index = 0;
+ if (ioctl(vhostfd, VHOST_NET_SET_BACKEND, &f) < 0) {
+ PMD_DRV_LOG(ERR, "VHOST_NET_SET_BACKEND fails, %s",
+ strerror(errno));
+ return -1;
+ }
+
+ f.index = 1;
+ if (ioctl(vhostfd, VHOST_NET_SET_BACKEND, &f) < 0) {
+ PMD_DRV_LOG(ERR, "VHOST_NET_SET_BACKEND fails, %s",
+ strerror(errno));
+ return -1;
+ }
+
+ return 0;
+}
+
+static int
+vhost_kernel_enable_queue_pair(struct virtio_user_dev *dev,
+ uint16_t pair_idx,
+ int enable)
+{
+ int hdr_size;
+ int vhostfd;
+ int tapfd;
+ int req_mq = (dev->max_queue_pairs > 1);
+
+ vhostfd = dev->vhostfds[pair_idx];
+
+ if (!enable) {
+ if (dev->tapfds[pair_idx] >= 0) {
+ close(dev->tapfds[pair_idx]);
+ dev->tapfds[pair_idx] = -1;
+ }
+ return vhost_kernel_set_backend(vhostfd, -1);
+ } else if (dev->tapfds[pair_idx] >= 0) {
+ return 0;
+ }
+
+ if ((dev->features & (1ULL << VIRTIO_NET_F_MRG_RXBUF)) ||
+ (dev->features & (1ULL << VIRTIO_F_VERSION_1)))
+ hdr_size = sizeof(struct virtio_net_hdr_mrg_rxbuf);
+ else
+ hdr_size = sizeof(struct virtio_net_hdr);
+
+ tapfd = vhost_kernel_open_tap(&dev->ifname, hdr_size, req_mq);
+ if (tapfd < 0) {
+ PMD_DRV_LOG(ERR, "fail to open tap for vhost kernel");
+ return -1;
+ }
+
+ if (vhost_kernel_set_backend(vhostfd, tapfd) < 0) {
+ PMD_DRV_LOG(ERR, "fail to set backend for vhost kernel");
+ close(tapfd);
+ return -1;
+ }
+
+ dev->tapfds[pair_idx] = tapfd;
+ return 0;
+}
+
+struct virtio_user_backend_ops ops_kernel = {
+ .setup = vhost_kernel_setup,
+ .send_request = vhost_kernel_ioctl,
+ .enable_qp = vhost_kernel_enable_queue_pair
+};