@@ -118,6 +118,8 @@ typedef enum VhostUserBackendRequest {
VHOST_USER_BACKEND_SHARED_OBJECT_LOOKUP = 8,
VHOST_USER_BACKEND_SHMEM_MAP = 9,
VHOST_USER_BACKEND_SHMEM_UNMAP = 10,
+ VHOST_USER_BACKEND_MEM_READ = 11,
+ VHOST_USER_BACKEND_MEM_WRITE = 12,
VHOST_USER_BACKEND_MAX
} VhostUserBackendRequest;
@@ -145,6 +147,12 @@ typedef struct VhostUserShMemConfig {
uint64_t memory_sizes[VHOST_MEMORY_BASELINE_NREGIONS];
} VhostUserShMemConfig;
+typedef struct VhostUserMemRWMsg {
+ uint64_t guest_address;
+ uint32_t size;
+ uint8_t data[];
+} VhostUserMemRWMsg;
+
typedef struct VhostUserLog {
uint64_t mmap_size;
uint64_t mmap_offset;
@@ -253,6 +261,7 @@ typedef union {
VhostUserTransferDeviceState transfer_state;
VhostUserMMap mmap;
VhostUserShMemConfig shmem;
+ VhostUserMemRWMsg mem_rw;
} VhostUserPayload;
typedef struct VhostUserMsg {
@@ -1871,6 +1880,22 @@ vhost_user_backend_handle_shmem_unmap(struct vhost_dev *dev,
return 0;
}
+static int
+vhost_user_backend_handle_mem_read(struct vhost_dev *dev,
+ VhostUserMemRWMsg *mem_rw)
+{
+ /* TODO */
+ return -EPERM;
+}
+
+static int
+vhost_user_backend_handle_mem_write(struct vhost_dev *dev,
+ VhostUserMemRWMsg *mem_rw)
+{
+ /* TODO */
+ return -EPERM;
+}
+
static void close_backend_channel(struct vhost_user *u)
{
g_source_destroy(u->backend_src);
@@ -1946,6 +1971,12 @@ static gboolean backend_read(QIOChannel *ioc, GIOCondition condition,
case VHOST_USER_BACKEND_SHMEM_UNMAP:
ret = vhost_user_backend_handle_shmem_unmap(dev, &payload.mmap);
break;
+ case VHOST_USER_BACKEND_MEM_READ:
+ ret = vhost_user_backend_handle_mem_read(dev, &payload.mem_rw);
+ break;
+ case VHOST_USER_BACKEND_MEM_WRITE:
+ ret = vhost_user_backend_handle_mem_write(dev, &payload.mem_rw);
+ break;
default:
error_report("Received unexpected msg type: %d.", hdr.request);
ret = -EINVAL;
@@ -1651,6 +1651,90 @@ vu_shmem_unmap(VuDev *dev, uint8_t shmid, uint64_t fd_offset,
return vu_process_message_reply(dev, &vmsg);
}
+bool
+vu_send_mem_read(VuDev *dev, uint64_t guest_addr, uint32_t size,
+ uint8_t *data)
+{
+ VhostUserMsg msg_reply;
+ VhostUserMsg msg = {
+ .request = VHOST_USER_BACKEND_MEM_READ,
+ .size = sizeof(msg.payload.mem_rw),
+ .flags = VHOST_USER_VERSION | VHOST_USER_NEED_REPLY_MASK,
+ .payload = {
+ .mem_rw = {
+ .guest_address = guest_addr,
+ .size = size,
+ }
+ }
+ };
+
+ pthread_mutex_lock(&dev->backend_mutex);
+ if (!vu_message_write(dev, dev->backend_fd, &msg)) {
+ goto out_err;
+ }
+
+ if (!vu_message_read_default(dev, dev->backend_fd, &msg_reply)) {
+ goto out_err;
+ }
+
+ if (msg_reply.request != msg.request) {
+ DPRINT("Received unexpected msg type. Expected %d, received %d",
+ msg.request, msg_reply.request);
+ goto out_err;
+ }
+
+ if (msg_reply.payload.mem_rw.size != size) {
+ DPRINT("Received unexpected number of bytes in the response. "
+ "Expected %d, received %d",
+ size, msg_reply.payload.mem_rw.size);
+ goto out_err;
+ }
+
+ data = malloc(msg_reply.payload.mem_rw.size);
+ if (!data) {
+ DPRINT("Failed to malloc read memory data");
+ goto out_err;
+ }
+
+ memcpy(data, msg_reply.payload.mem_rw.data, size);
+ pthread_mutex_unlock(&dev->backend_mutex);
+ return true;
+
+out_err:
+ pthread_mutex_unlock(&dev->backend_mutex);
+ return false;
+}
+
+bool
+vu_send_mem_write(VuDev *dev, uint64_t guest_addr, uint32_t size,
+ uint8_t *data)
+{
+ VhostUserMsg msg = {
+ .request = VHOST_USER_BACKEND_MEM_WRITE,
+ .size = sizeof(msg.payload.mem_rw),
+ .flags = VHOST_USER_VERSION,
+ .payload = {
+ .mem_rw = {
+ .guest_address = guest_addr,
+ .size = size,
+ }
+ }
+ };
+ memcpy(msg.payload.mem_rw.data, data, size);
+
+ if (vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_REPLY_ACK)) {
+ msg.flags |= VHOST_USER_NEED_REPLY_MASK;
+ }
+
+ if (!vu_message_write(dev, dev->backend_fd, &msg)) {
+ pthread_mutex_unlock(&dev->backend_mutex);
+ return false;
+ }
+
+ /* Also unlocks the backend_mutex */
+ return vu_process_message_reply(dev, &msg);
+}
+
static bool
vu_set_vring_call_exec(VuDev *dev, VhostUserMsg *vmsg)
{
@@ -129,6 +129,8 @@ typedef enum VhostUserBackendRequest {
VHOST_USER_BACKEND_SHARED_OBJECT_LOOKUP = 8,
VHOST_USER_BACKEND_SHMEM_MAP = 9,
VHOST_USER_BACKEND_SHMEM_UNMAP = 10,
+ VHOST_USER_BACKEND_MEM_READ = 11,
+ VHOST_USER_BACKEND_MEM_WRITE = 12,
VHOST_USER_BACKEND_MAX
} VhostUserBackendRequest;
@@ -152,6 +154,12 @@ typedef struct VhostUserMemRegMsg {
VhostUserMemoryRegion region;
} VhostUserMemRegMsg;
+typedef struct VhostUserMemRWMsg {
+ uint64_t guest_address;
+ uint32_t size;
+ uint8_t data[];
+} VhostUserMemRWMsg;
+
typedef struct VhostUserLog {
uint64_t mmap_size;
uint64_t mmap_offset;
@@ -235,6 +243,7 @@ typedef struct VhostUserMsg {
VhostUserInflight inflight;
VhostUserShared object;
VhostUserMMap mmap;
+ VhostUserMemRWMsg mem_rw;
} payload;
int fds[VHOST_MEMORY_BASELINE_NREGIONS];
@@ -650,6 +659,35 @@ bool vu_shmem_map(VuDev *dev, uint8_t shmid, uint64_t fd_offset,
bool vu_shmem_unmap(VuDev *dev, uint8_t shmid, uint64_t fd_offset,
uint64_t shm_offset, uint64_t len);
+/**
+ * vu_send_mem_read:
+ * @dev: a VuDev context
+ * @guest_addr: guest physical address to read
+ * @size: number of bytes to read
+ * @data: head of an unitialized bytes array
+ *
+ * Reads `size` bytes of `guest_addr` in the frontend and stores
+ * them in `data`.
+ *
+ * Returns: TRUE on success, FALSE on failure.
+ */
+bool vu_send_mem_read(VuDev *dev, uint64_t guest_addr, uint32_t size,
+ uint8_t *data);
+
+/**
+ * vu_send_mem_write:
+ * @dev: a VuDev context
+ * @guest_addr: guest physical address to write
+ * @size: number of bytes to write
+ * @data: head of an array with `size` bytes to write
+ *
+ * Writes `size` bytes from `data` into `guest_addr` in the frontend.
+ *
+ * Returns: TRUE on success, FALSE on failure.
+ */
+bool vu_send_mem_write(VuDev *dev, uint64_t guest_addr, uint32_t size,
+ uint8_t *data);
+
/**
* vu_queue_set_notification:
* @dev: a VuDev context
With SHMEM_MAP messages, sharing descriptors between devices will cause that these devices do not see the mappings, and fail to access these memory regions. To solve this, introduce MEM_READ/WRITE requests that will get triggered as a fallback when vhost-user memory translation fails. Signed-off-by: Albert Esteve <aesteve@redhat.com> --- hw/virtio/vhost-user.c | 31 +++++++++ subprojects/libvhost-user/libvhost-user.c | 84 +++++++++++++++++++++++ subprojects/libvhost-user/libvhost-user.h | 38 ++++++++++ 3 files changed, 153 insertions(+)