Imported Upstream version 17.05

Change-Id: Id1e419c5a214e4a18739663b91f0f9a549f1fdc6
Signed-off-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>

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
+};