diff --git a/docs/interop/vhost-user.txt b/docs/interop/vhost-user.txt index d49444e0373744f6781e98795b68da976c110ede..0875ef4ec3437337a568c0cde63a3df5df446cac 100644 --- a/docs/interop/vhost-user.txt +++ b/docs/interop/vhost-user.txt @@ -119,6 +119,19 @@ Depending on the request type, payload can be: - 3: IOTLB invalidate - 4: IOTLB access fail + * Virtio device config space + ----------------------------------- + | offset | size | flags | payload | + ----------------------------------- + + Offset: a 32-bit offset of virtio device's configuration space + Size: a 32-bit configuration space access size in bytes + Flags: a 32-bit value: + - 0: Vhost master messages used for writeable fields + - 1: Vhost master messages used for live migration + Payload: Size bytes array holding the contents of the virtio + device's configuration space + In QEMU the vhost-user message is implemented with the following struct: typedef struct VhostUserMsg { @@ -132,6 +145,7 @@ typedef struct VhostUserMsg { VhostUserMemory memory; VhostUserLog log; struct vhost_iotlb_msg iotlb; + VhostUserConfig config; }; } QEMU_PACKED VhostUserMsg; @@ -623,6 +637,32 @@ Master message types and expect this message once (per VQ) during device configuration (ie. before the master starts the VQ). + * VHOST_USER_GET_CONFIG + + Id: 24 + Equivalent ioctl: N/A + Master payload: virtio device config space + Slave payload: virtio device config space + + Submitted by the vhost-user master to fetch the contents of the virtio + device configuration space, vhost-user slave's payload size MUST match + master's request, vhost-user slave uses zero length of payload to + indicate an error to vhost-user master. The vhost-user master may + cache the contents to avoid repeated VHOST_USER_GET_CONFIG calls. + +* VHOST_USER_SET_CONFIG + + Id: 25 + Equivalent ioctl: N/A + Master payload: virtio device config space + Slave payload: N/A + + Submitted by the vhost-user master when the Guest changes the virtio + device configuration space and also can be used for live migration + on the destination host. The vhost-user slave must check the flags + field, and slaves MUST NOT accept SET_CONFIG for read-only + configuration space fields unless the live migration bit is set. + Slave message types ------------------- @@ -641,6 +681,21 @@ Slave message types This request should be send only when VIRTIO_F_IOMMU_PLATFORM feature has been successfully negotiated. +* VHOST_USER_SLAVE_CONFIG_CHANGE_MSG + + Id: 2 + Equivalent ioctl: N/A + Slave payload: N/A + Master payload: N/A + + Vhost-user slave sends such messages to notify that the virtio device's + configuration space has changed, for those host devices which can support + such feature, host driver can send VHOST_USER_GET_CONFIG message to slave + to get the latest content. If VHOST_USER_PROTOCOL_F_REPLY_ACK is + negotiated, and slave set the VHOST_USER_NEED_REPLY flag, master must + respond with zero when operation is successfully completed, or non-zero + otherwise. + VHOST_USER_PROTOCOL_F_REPLY_ACK: ------------------------------- The original vhost-user specification only demands replies for certain diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c index 093675ed98fa2546566678aa682589b5905a786f..8b946880fe7ff2588aa7efcb39ab44f84db0f8dd 100644 --- a/hw/virtio/vhost-user.c +++ b/hw/virtio/vhost-user.c @@ -26,6 +26,11 @@ #define VHOST_MEMORY_MAX_NREGIONS 8 #define VHOST_USER_F_PROTOCOL_FEATURES 30 +/* + * Maximum size of virtio device config space + */ +#define VHOST_USER_MAX_CONFIG_SIZE 256 + enum VhostUserProtocolFeature { VHOST_USER_PROTOCOL_F_MQ = 0, VHOST_USER_PROTOCOL_F_LOG_SHMFD = 1, @@ -65,12 +70,15 @@ typedef enum VhostUserRequest { VHOST_USER_SET_SLAVE_REQ_FD = 21, VHOST_USER_IOTLB_MSG = 22, VHOST_USER_SET_VRING_ENDIAN = 23, + VHOST_USER_GET_CONFIG = 24, + VHOST_USER_SET_CONFIG = 25, VHOST_USER_MAX } VhostUserRequest; typedef enum VhostUserSlaveRequest { VHOST_USER_SLAVE_NONE = 0, VHOST_USER_SLAVE_IOTLB_MSG = 1, + VHOST_USER_SLAVE_CONFIG_CHANGE_MSG = 2, VHOST_USER_SLAVE_MAX } VhostUserSlaveRequest; @@ -92,6 +100,18 @@ typedef struct VhostUserLog { uint64_t mmap_offset; } VhostUserLog; +typedef struct VhostUserConfig { + uint32_t offset; + uint32_t size; + uint32_t flags; + uint8_t region[VHOST_USER_MAX_CONFIG_SIZE]; +} VhostUserConfig; + +static VhostUserConfig c __attribute__ ((unused)); +#define VHOST_USER_CONFIG_HDR_SIZE (sizeof(c.offset) \ + + sizeof(c.size) \ + + sizeof(c.flags)) + typedef struct VhostUserMsg { VhostUserRequest request; @@ -109,6 +129,7 @@ typedef struct VhostUserMsg { VhostUserMemory memory; VhostUserLog log; struct vhost_iotlb_msg iotlb; + VhostUserConfig config; } payload; } QEMU_PACKED VhostUserMsg; @@ -608,6 +629,21 @@ static int vhost_user_reset_device(struct vhost_dev *dev) return 0; } +static int vhost_user_slave_handle_config_change(struct vhost_dev *dev) +{ + int ret = -1; + + if (!dev->config_ops) { + return -1; + } + + if (dev->config_ops->vhost_dev_config_notifier) { + ret = dev->config_ops->vhost_dev_config_notifier(dev); + } + + return ret; +} + static void slave_read(void *opaque) { struct vhost_dev *dev = opaque; @@ -640,6 +676,9 @@ static void slave_read(void *opaque) case VHOST_USER_SLAVE_IOTLB_MSG: ret = vhost_backend_handle_iotlb_msg(dev, &msg.payload.iotlb); break; + case VHOST_USER_SLAVE_CONFIG_CHANGE_MSG : + ret = vhost_user_slave_handle_config_change(dev); + break; default: error_report("Received unexpected msg type."); ret = -EINVAL; @@ -922,6 +961,83 @@ static void vhost_user_set_iotlb_callback(struct vhost_dev *dev, int enabled) /* No-op as the receive channel is not dedicated to IOTLB messages. */ } +static int vhost_user_get_config(struct vhost_dev *dev, uint8_t *config, + uint32_t config_len) +{ + VhostUserMsg msg = { + msg.request = VHOST_USER_GET_CONFIG, + msg.flags = VHOST_USER_VERSION, + msg.size = VHOST_USER_CONFIG_HDR_SIZE + config_len, + }; + + if (config_len > VHOST_USER_MAX_CONFIG_SIZE) { + return -1; + } + + msg.payload.config.offset = 0; + msg.payload.config.size = config_len; + if (vhost_user_write(dev, &msg, NULL, 0) < 0) { + return -1; + } + + if (vhost_user_read(dev, &msg) < 0) { + return -1; + } + + if (msg.request != VHOST_USER_GET_CONFIG) { + error_report("Received unexpected msg type. Expected %d received %d", + VHOST_USER_GET_CONFIG, msg.request); + return -1; + } + + if (msg.size != VHOST_USER_CONFIG_HDR_SIZE + config_len) { + error_report("Received bad msg size."); + return -1; + } + + memcpy(config, msg.payload.config.region, config_len); + + return 0; +} + +static int vhost_user_set_config(struct vhost_dev *dev, const uint8_t *data, + uint32_t offset, uint32_t size, uint32_t flags) +{ + uint8_t *p; + bool reply_supported = virtio_has_feature(dev->protocol_features, + VHOST_USER_PROTOCOL_F_REPLY_ACK); + + VhostUserMsg msg = { + msg.request = VHOST_USER_SET_CONFIG, + msg.flags = VHOST_USER_VERSION, + msg.size = VHOST_USER_CONFIG_HDR_SIZE + size, + }; + + if (reply_supported) { + msg.flags |= VHOST_USER_NEED_REPLY_MASK; + } + + if (size > VHOST_USER_MAX_CONFIG_SIZE) { + return -1; + } + + msg.payload.config.offset = offset, + msg.payload.config.size = size, + msg.payload.config.flags = flags, + p = msg.payload.config.region; + memcpy(p, data, size); + + if (vhost_user_write(dev, &msg, NULL, 0) < 0) { + return -1; + } + + if (reply_supported) { + return process_message_reply(dev, &msg); + } + + return 0; +} + const VhostOps user_ops = { .backend_type = VHOST_BACKEND_TYPE_USER, .vhost_backend_init = vhost_user_init, @@ -948,4 +1064,6 @@ const VhostOps user_ops = { .vhost_net_set_mtu = vhost_user_net_set_mtu, .vhost_set_iotlb_callback = vhost_user_set_iotlb_callback, .vhost_send_device_iotlb_msg = vhost_user_send_device_iotlb_msg, + .vhost_get_config = vhost_user_get_config, + .vhost_set_config = vhost_user_set_config, }; diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c index e4290ce93d923beede690f4b6bf68c52ab41e8d0..386aef85be9cf41ea3a11793668568a0e22157ab 100644 --- a/hw/virtio/vhost.c +++ b/hw/virtio/vhost.c @@ -1505,6 +1505,38 @@ void vhost_ack_features(struct vhost_dev *hdev, const int *feature_bits, } } +int vhost_dev_get_config(struct vhost_dev *hdev, uint8_t *config, + uint32_t config_len) +{ + assert(hdev->vhost_ops); + + if (hdev->vhost_ops->vhost_get_config) { + return hdev->vhost_ops->vhost_get_config(hdev, config, config_len); + } + + return -1; +} + +int vhost_dev_set_config(struct vhost_dev *hdev, const uint8_t *data, + uint32_t offset, uint32_t size, uint32_t flags) +{ + assert(hdev->vhost_ops); + + if (hdev->vhost_ops->vhost_set_config) { + return hdev->vhost_ops->vhost_set_config(hdev, data, offset, + size, flags); + } + + return -1; +} + +void vhost_dev_set_config_notifier(struct vhost_dev *hdev, + const VhostDevConfigOps *ops) +{ + assert(hdev->vhost_ops); + hdev->config_ops = ops; +} + /* Host notifiers must be enabled at this point. */ int vhost_dev_start(struct vhost_dev *hdev, VirtIODevice *vdev) { diff --git a/include/hw/virtio/vhost-backend.h b/include/hw/virtio/vhost-backend.h index a7a5f22bc6d66963d85be59145663c7c4fd39ce1..592254f40dc565b74de130606b5d3604f65145f9 100644 --- a/include/hw/virtio/vhost-backend.h +++ b/include/hw/virtio/vhost-backend.h @@ -20,6 +20,11 @@ typedef enum VhostBackendType { VHOST_BACKEND_TYPE_MAX = 3, } VhostBackendType; +typedef enum VhostSetConfigType { + VHOST_SET_CONFIG_TYPE_MASTER = 0, + VHOST_SET_CONFIG_TYPE_MIGRATION = 1, +} VhostSetConfigType; + struct vhost_dev; struct vhost_log; struct vhost_memory; @@ -84,6 +89,11 @@ typedef void (*vhost_set_iotlb_callback_op)(struct vhost_dev *dev, int enabled); typedef int (*vhost_send_device_iotlb_msg_op)(struct vhost_dev *dev, struct vhost_iotlb_msg *imsg); +typedef int (*vhost_set_config_op)(struct vhost_dev *dev, const uint8_t *data, + uint32_t offset, uint32_t size, + uint32_t flags); +typedef int (*vhost_get_config_op)(struct vhost_dev *dev, uint8_t *config, + uint32_t config_len); typedef struct VhostOps { VhostBackendType backend_type; @@ -118,6 +128,8 @@ typedef struct VhostOps { vhost_vsock_set_running_op vhost_vsock_set_running; vhost_set_iotlb_callback_op vhost_set_iotlb_callback; vhost_send_device_iotlb_msg_op vhost_send_device_iotlb_msg; + vhost_get_config_op vhost_get_config; + vhost_set_config_op vhost_set_config; } VhostOps; extern const VhostOps user_ops; diff --git a/include/hw/virtio/vhost.h b/include/hw/virtio/vhost.h index 467dc7794b45f78f0c7032a842128fc9beaf3dfa..1dc2d73d765798a7bff950e7a90a642377884009 100644 --- a/include/hw/virtio/vhost.h +++ b/include/hw/virtio/vhost.h @@ -46,6 +46,12 @@ struct vhost_iommu { QLIST_ENTRY(vhost_iommu) iommu_next; }; +typedef struct VhostDevConfigOps { + /* Vhost device config space changed callback + */ + int (*vhost_dev_config_notifier)(struct vhost_dev *dev); +} VhostDevConfigOps; + struct vhost_memory; struct vhost_dev { VirtIODevice *vdev; @@ -76,6 +82,7 @@ struct vhost_dev { QLIST_ENTRY(vhost_dev) entry; QLIST_HEAD(, vhost_iommu) iommu_list; IOMMUNotifier n; + const VhostDevConfigOps *config_ops; }; int vhost_dev_init(struct vhost_dev *hdev, void *opaque, @@ -106,4 +113,12 @@ int vhost_net_set_backend(struct vhost_dev *hdev, struct vhost_vring_file *file); int vhost_device_iotlb_miss(struct vhost_dev *dev, uint64_t iova, int write); +int vhost_dev_get_config(struct vhost_dev *dev, uint8_t *config, + uint32_t config_len); +int vhost_dev_set_config(struct vhost_dev *dev, const uint8_t *data, + uint32_t offset, uint32_t size, uint32_t flags); +/* notifier callback in case vhost device config space changed + */ +void vhost_dev_set_config_notifier(struct vhost_dev *dev, + const VhostDevConfigOps *ops); #endif