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authorDaniel Baumann <mail@daniel-baumann.ch>2025-06-06 10:05:23 +0000
committerDaniel Baumann <mail@daniel-baumann.ch>2025-06-06 10:05:23 +0000
commit755cc582a2473d06f3a2131d506d0311cc70e9f9 (patch)
tree3efb1ddb8d57bbb4539ac0d229b384871c57820f /hw/virtio/vhost-backend.c
parentInitial commit. (diff)
downloadqemu-upstream.tar.xz
qemu-upstream.zip
Adding upstream version 1:7.2+dfsg.upstream/1%7.2+dfsgupstream
Signed-off-by: Daniel Baumann <mail@daniel-baumann.ch>
Diffstat (limited to 'hw/virtio/vhost-backend.c')
-rw-r--r--hw/virtio/vhost-backend.c410
1 files changed, 410 insertions, 0 deletions
diff --git a/hw/virtio/vhost-backend.c b/hw/virtio/vhost-backend.c
new file mode 100644
index 00000000..8e581575
--- /dev/null
+++ b/hw/virtio/vhost-backend.c
@@ -0,0 +1,410 @@
+/*
+ * vhost-backend
+ *
+ * Copyright (c) 2013 Virtual Open Systems Sarl.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#include "qemu/osdep.h"
+#include "hw/virtio/vhost.h"
+#include "hw/virtio/vhost-backend.h"
+#include "qemu/error-report.h"
+#include "qemu/main-loop.h"
+#include "standard-headers/linux/vhost_types.h"
+
+#include "hw/virtio/vhost-vdpa.h"
+#ifdef CONFIG_VHOST_KERNEL
+#include <linux/vhost.h>
+#include <sys/ioctl.h>
+
+static int vhost_kernel_call(struct vhost_dev *dev, unsigned long int request,
+ void *arg)
+{
+ int fd = (uintptr_t) dev->opaque;
+ int ret;
+
+ assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_KERNEL);
+
+ ret = ioctl(fd, request, arg);
+ return ret < 0 ? -errno : ret;
+}
+
+static int vhost_kernel_init(struct vhost_dev *dev, void *opaque, Error **errp)
+{
+ assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_KERNEL);
+
+ dev->opaque = opaque;
+
+ return 0;
+}
+
+static int vhost_kernel_cleanup(struct vhost_dev *dev)
+{
+ int fd = (uintptr_t) dev->opaque;
+
+ assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_KERNEL);
+
+ return close(fd) < 0 ? -errno : 0;
+}
+
+static int vhost_kernel_memslots_limit(struct vhost_dev *dev)
+{
+ int limit = 64;
+ char *s;
+
+ if (g_file_get_contents("/sys/module/vhost/parameters/max_mem_regions",
+ &s, NULL, NULL)) {
+ uint64_t val = g_ascii_strtoull(s, NULL, 10);
+ if (val < INT_MAX && val > 0) {
+ g_free(s);
+ return val;
+ }
+ error_report("ignoring invalid max_mem_regions value in vhost module:"
+ " %s", s);
+ }
+ g_free(s);
+ return limit;
+}
+
+static int vhost_kernel_net_set_backend(struct vhost_dev *dev,
+ struct vhost_vring_file *file)
+{
+ return vhost_kernel_call(dev, VHOST_NET_SET_BACKEND, file);
+}
+
+static int vhost_kernel_scsi_set_endpoint(struct vhost_dev *dev,
+ struct vhost_scsi_target *target)
+{
+ return vhost_kernel_call(dev, VHOST_SCSI_SET_ENDPOINT, target);
+}
+
+static int vhost_kernel_scsi_clear_endpoint(struct vhost_dev *dev,
+ struct vhost_scsi_target *target)
+{
+ return vhost_kernel_call(dev, VHOST_SCSI_CLEAR_ENDPOINT, target);
+}
+
+static int vhost_kernel_scsi_get_abi_version(struct vhost_dev *dev, int *version)
+{
+ return vhost_kernel_call(dev, VHOST_SCSI_GET_ABI_VERSION, version);
+}
+
+static int vhost_kernel_set_log_base(struct vhost_dev *dev, uint64_t base,
+ struct vhost_log *log)
+{
+ return vhost_kernel_call(dev, VHOST_SET_LOG_BASE, &base);
+}
+
+static int vhost_kernel_set_mem_table(struct vhost_dev *dev,
+ struct vhost_memory *mem)
+{
+ return vhost_kernel_call(dev, VHOST_SET_MEM_TABLE, mem);
+}
+
+static int vhost_kernel_set_vring_addr(struct vhost_dev *dev,
+ struct vhost_vring_addr *addr)
+{
+ return vhost_kernel_call(dev, VHOST_SET_VRING_ADDR, addr);
+}
+
+static int vhost_kernel_set_vring_endian(struct vhost_dev *dev,
+ struct vhost_vring_state *ring)
+{
+ return vhost_kernel_call(dev, VHOST_SET_VRING_ENDIAN, ring);
+}
+
+static int vhost_kernel_set_vring_num(struct vhost_dev *dev,
+ struct vhost_vring_state *ring)
+{
+ return vhost_kernel_call(dev, VHOST_SET_VRING_NUM, ring);
+}
+
+static int vhost_kernel_set_vring_base(struct vhost_dev *dev,
+ struct vhost_vring_state *ring)
+{
+ return vhost_kernel_call(dev, VHOST_SET_VRING_BASE, ring);
+}
+
+static int vhost_kernel_get_vring_base(struct vhost_dev *dev,
+ struct vhost_vring_state *ring)
+{
+ return vhost_kernel_call(dev, VHOST_GET_VRING_BASE, ring);
+}
+
+static int vhost_kernel_set_vring_kick(struct vhost_dev *dev,
+ struct vhost_vring_file *file)
+{
+ return vhost_kernel_call(dev, VHOST_SET_VRING_KICK, file);
+}
+
+static int vhost_kernel_set_vring_call(struct vhost_dev *dev,
+ struct vhost_vring_file *file)
+{
+ return vhost_kernel_call(dev, VHOST_SET_VRING_CALL, file);
+}
+
+static int vhost_kernel_set_vring_err(struct vhost_dev *dev,
+ struct vhost_vring_file *file)
+{
+ return vhost_kernel_call(dev, VHOST_SET_VRING_ERR, file);
+}
+
+static int vhost_kernel_set_vring_busyloop_timeout(struct vhost_dev *dev,
+ struct vhost_vring_state *s)
+{
+ return vhost_kernel_call(dev, VHOST_SET_VRING_BUSYLOOP_TIMEOUT, s);
+}
+
+static int vhost_kernel_set_features(struct vhost_dev *dev,
+ uint64_t features)
+{
+ return vhost_kernel_call(dev, VHOST_SET_FEATURES, &features);
+}
+
+static int vhost_kernel_set_backend_cap(struct vhost_dev *dev)
+{
+ uint64_t features;
+ uint64_t f = 0x1ULL << VHOST_BACKEND_F_IOTLB_MSG_V2;
+ int r;
+
+ if (vhost_kernel_call(dev, VHOST_GET_BACKEND_FEATURES, &features)) {
+ return 0;
+ }
+
+ features &= f;
+ r = vhost_kernel_call(dev, VHOST_SET_BACKEND_FEATURES,
+ &features);
+ if (r) {
+ return 0;
+ }
+
+ dev->backend_cap = features;
+
+ return 0;
+}
+
+static int vhost_kernel_get_features(struct vhost_dev *dev,
+ uint64_t *features)
+{
+ return vhost_kernel_call(dev, VHOST_GET_FEATURES, features);
+}
+
+static int vhost_kernel_set_owner(struct vhost_dev *dev)
+{
+ return vhost_kernel_call(dev, VHOST_SET_OWNER, NULL);
+}
+
+static int vhost_kernel_reset_device(struct vhost_dev *dev)
+{
+ return vhost_kernel_call(dev, VHOST_RESET_OWNER, NULL);
+}
+
+static int vhost_kernel_get_vq_index(struct vhost_dev *dev, int idx)
+{
+ assert(idx >= dev->vq_index && idx < dev->vq_index + dev->nvqs);
+
+ return idx - dev->vq_index;
+}
+
+static int vhost_kernel_vsock_set_guest_cid(struct vhost_dev *dev,
+ uint64_t guest_cid)
+{
+ return vhost_kernel_call(dev, VHOST_VSOCK_SET_GUEST_CID, &guest_cid);
+}
+
+static int vhost_kernel_vsock_set_running(struct vhost_dev *dev, int start)
+{
+ return vhost_kernel_call(dev, VHOST_VSOCK_SET_RUNNING, &start);
+}
+
+static void vhost_kernel_iotlb_read(void *opaque)
+{
+ struct vhost_dev *dev = opaque;
+ ssize_t len;
+
+ if (dev->backend_cap &
+ (0x1ULL << VHOST_BACKEND_F_IOTLB_MSG_V2)) {
+ struct vhost_msg_v2 msg;
+
+ while ((len = read((uintptr_t)dev->opaque, &msg, sizeof msg)) > 0) {
+ if (len < sizeof msg) {
+ error_report("Wrong vhost message len: %d", (int)len);
+ break;
+ }
+ if (msg.type != VHOST_IOTLB_MSG_V2) {
+ error_report("Unknown vhost iotlb message type");
+ break;
+ }
+
+ vhost_backend_handle_iotlb_msg(dev, &msg.iotlb);
+ }
+ } else {
+ struct vhost_msg msg;
+
+ while ((len = read((uintptr_t)dev->opaque, &msg, sizeof msg)) > 0) {
+ if (len < sizeof msg) {
+ error_report("Wrong vhost message len: %d", (int)len);
+ break;
+ }
+ if (msg.type != VHOST_IOTLB_MSG) {
+ error_report("Unknown vhost iotlb message type");
+ break;
+ }
+
+ vhost_backend_handle_iotlb_msg(dev, &msg.iotlb);
+ }
+ }
+}
+
+static int vhost_kernel_send_device_iotlb_msg(struct vhost_dev *dev,
+ struct vhost_iotlb_msg *imsg)
+{
+ if (dev->backend_cap & (1ULL << VHOST_BACKEND_F_IOTLB_MSG_V2)) {
+ struct vhost_msg_v2 msg = {};
+
+ msg.type = VHOST_IOTLB_MSG_V2;
+ msg.iotlb = *imsg;
+
+ if (write((uintptr_t)dev->opaque, &msg, sizeof msg) != sizeof msg) {
+ error_report("Fail to update device iotlb");
+ return -EFAULT;
+ }
+ } else {
+ struct vhost_msg msg = {};
+
+ msg.type = VHOST_IOTLB_MSG;
+ msg.iotlb = *imsg;
+
+ if (write((uintptr_t)dev->opaque, &msg, sizeof msg) != sizeof msg) {
+ error_report("Fail to update device iotlb");
+ return -EFAULT;
+ }
+ }
+
+ return 0;
+}
+
+static void vhost_kernel_set_iotlb_callback(struct vhost_dev *dev,
+ int enabled)
+{
+ if (enabled)
+ qemu_set_fd_handler((uintptr_t)dev->opaque,
+ vhost_kernel_iotlb_read, NULL, dev);
+ else
+ qemu_set_fd_handler((uintptr_t)dev->opaque, NULL, NULL, NULL);
+}
+
+const VhostOps kernel_ops = {
+ .backend_type = VHOST_BACKEND_TYPE_KERNEL,
+ .vhost_backend_init = vhost_kernel_init,
+ .vhost_backend_cleanup = vhost_kernel_cleanup,
+ .vhost_backend_memslots_limit = vhost_kernel_memslots_limit,
+ .vhost_net_set_backend = vhost_kernel_net_set_backend,
+ .vhost_scsi_set_endpoint = vhost_kernel_scsi_set_endpoint,
+ .vhost_scsi_clear_endpoint = vhost_kernel_scsi_clear_endpoint,
+ .vhost_scsi_get_abi_version = vhost_kernel_scsi_get_abi_version,
+ .vhost_set_log_base = vhost_kernel_set_log_base,
+ .vhost_set_mem_table = vhost_kernel_set_mem_table,
+ .vhost_set_vring_addr = vhost_kernel_set_vring_addr,
+ .vhost_set_vring_endian = vhost_kernel_set_vring_endian,
+ .vhost_set_vring_num = vhost_kernel_set_vring_num,
+ .vhost_set_vring_base = vhost_kernel_set_vring_base,
+ .vhost_get_vring_base = vhost_kernel_get_vring_base,
+ .vhost_set_vring_kick = vhost_kernel_set_vring_kick,
+ .vhost_set_vring_call = vhost_kernel_set_vring_call,
+ .vhost_set_vring_err = vhost_kernel_set_vring_err,
+ .vhost_set_vring_busyloop_timeout =
+ vhost_kernel_set_vring_busyloop_timeout,
+ .vhost_set_features = vhost_kernel_set_features,
+ .vhost_get_features = vhost_kernel_get_features,
+ .vhost_set_backend_cap = vhost_kernel_set_backend_cap,
+ .vhost_set_owner = vhost_kernel_set_owner,
+ .vhost_reset_device = vhost_kernel_reset_device,
+ .vhost_get_vq_index = vhost_kernel_get_vq_index,
+ .vhost_vsock_set_guest_cid = vhost_kernel_vsock_set_guest_cid,
+ .vhost_vsock_set_running = vhost_kernel_vsock_set_running,
+ .vhost_set_iotlb_callback = vhost_kernel_set_iotlb_callback,
+ .vhost_send_device_iotlb_msg = vhost_kernel_send_device_iotlb_msg,
+};
+#endif
+
+int vhost_backend_update_device_iotlb(struct vhost_dev *dev,
+ uint64_t iova, uint64_t uaddr,
+ uint64_t len,
+ IOMMUAccessFlags perm)
+{
+ struct vhost_iotlb_msg imsg;
+
+ imsg.iova = iova;
+ imsg.uaddr = uaddr;
+ imsg.size = len;
+ imsg.type = VHOST_IOTLB_UPDATE;
+
+ switch (perm) {
+ case IOMMU_RO:
+ imsg.perm = VHOST_ACCESS_RO;
+ break;
+ case IOMMU_WO:
+ imsg.perm = VHOST_ACCESS_WO;
+ break;
+ case IOMMU_RW:
+ imsg.perm = VHOST_ACCESS_RW;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ if (dev->vhost_ops && dev->vhost_ops->vhost_send_device_iotlb_msg)
+ return dev->vhost_ops->vhost_send_device_iotlb_msg(dev, &imsg);
+
+ return -ENODEV;
+}
+
+int vhost_backend_invalidate_device_iotlb(struct vhost_dev *dev,
+ uint64_t iova, uint64_t len)
+{
+ struct vhost_iotlb_msg imsg;
+
+ imsg.iova = iova;
+ imsg.size = len;
+ imsg.type = VHOST_IOTLB_INVALIDATE;
+
+ if (dev->vhost_ops && dev->vhost_ops->vhost_send_device_iotlb_msg)
+ return dev->vhost_ops->vhost_send_device_iotlb_msg(dev, &imsg);
+
+ return -ENODEV;
+}
+
+int vhost_backend_handle_iotlb_msg(struct vhost_dev *dev,
+ struct vhost_iotlb_msg *imsg)
+{
+ int ret = 0;
+
+ if (unlikely(!dev->vdev)) {
+ error_report("Unexpected IOTLB message when virtio device is stopped");
+ return -EINVAL;
+ }
+
+ switch (imsg->type) {
+ case VHOST_IOTLB_MISS:
+ ret = vhost_device_iotlb_miss(dev, imsg->iova,
+ imsg->perm != VHOST_ACCESS_RO);
+ break;
+ case VHOST_IOTLB_ACCESS_FAIL:
+ /* FIXME: report device iotlb error */
+ error_report("Access failure IOTLB message type not supported");
+ ret = -ENOTSUP;
+ break;
+ case VHOST_IOTLB_UPDATE:
+ case VHOST_IOTLB_INVALIDATE:
+ default:
+ error_report("Unexpected IOTLB message type");
+ ret = -EINVAL;
+ break;
+ }
+
+ return ret;
+}