On Wed, May 24, 2023 at 11:13:32AM +0200, Albert Esteve wrote: > Add new vhost-user protocol message > `VHOST_USER_BACKEND_SHARED_OBJECT`. This new > message is sent from vhost-user back-ends > to interact with the virtio-dmabuf table > in order to add, remove, or lookup for > virtio dma-buf shared objects. > > The action taken in the front-end depends > on the type stored in the payload struct. > > In the libvhost-user library add helper > functions to allow sending messages to > interact with the virtio shared objects > hash table. > > Signed-off-by: Albert Esteve <aest...@redhat.com> > --- > docs/interop/vhost-user.rst | 15 ++++ > hw/virtio/vhost-user.c | 68 ++++++++++++++++++ > subprojects/libvhost-user/libvhost-user.c | 88 +++++++++++++++++++++++ > subprojects/libvhost-user/libvhost-user.h | 56 +++++++++++++++ > 4 files changed, 227 insertions(+) > > diff --git a/docs/interop/vhost-user.rst b/docs/interop/vhost-user.rst > index 5a070adbc1..d3d8db41e5 100644 > --- a/docs/interop/vhost-user.rst > +++ b/docs/interop/vhost-user.rst > @@ -1528,6 +1528,21 @@ is sent by the front-end. > > The state.num field is currently reserved and must be set to 0. > > +``VHOST_USER_BACKEND_SHARED_OBJECT`` > + :id: 6 > + :equivalent ioctl: N/A > + :request payload: ``struct VhostUserShared`` > + :reply payload: ``struct VhostUserShared`` (only for ``LOOKUP`` requests) > + > + Backends that need to interact with the virtio-dmabuf shared table API > + can send this message. The operation is determined by the ``type`` member > + of the payload struct. The valid values for the operation type are > + ``VHOST_SHARED_OBJECT_*`` members, i.e., ``ADD``, ``LOOKUP``, and > ``REMOVE``. > + ``LOOKUP`` operations require the ``VHOST_USER_NEED_REPLY_MASK`` flag to be > + set by the back-end, and the front-end will then send the dma-buf fd as > + a response if the UUID matches an object in the table, or a negative value > + otherwise. > + > .. _reply_ack: > > VHOST_USER_PROTOCOL_F_REPLY_ACK > diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c > index 74a2a28663..5ac5f0eafd 100644 > --- a/hw/virtio/vhost-user.c > +++ b/hw/virtio/vhost-user.c > @@ -10,6 +10,7 @@ > > #include "qemu/osdep.h" > #include "qapi/error.h" > +#include "hw/virtio/virtio-dmabuf.h" > #include "hw/virtio/vhost.h" > #include "hw/virtio/vhost-user.h" > #include "hw/virtio/vhost-backend.h" > @@ -20,6 +21,7 @@ > #include "sysemu/kvm.h" > #include "qemu/error-report.h" > #include "qemu/main-loop.h" > +#include "qemu/uuid.h" > #include "qemu/sockets.h" > #include "sysemu/runstate.h" > #include "sysemu/cryptodev.h" > @@ -128,6 +130,7 @@ typedef enum VhostUserSlaveRequest { > VHOST_USER_BACKEND_IOTLB_MSG = 1, > VHOST_USER_BACKEND_CONFIG_CHANGE_MSG = 2, > VHOST_USER_BACKEND_VRING_HOST_NOTIFIER_MSG = 3, > + VHOST_USER_BACKEND_SHARED_OBJECT = 6, > VHOST_USER_BACKEND_MAX > } VhostUserSlaveRequest; > > @@ -190,6 +193,18 @@ typedef struct VhostUserInflight { > uint16_t queue_size; > } VhostUserInflight; > > +typedef enum VhostUserSharedType { > + VHOST_SHARED_OBJECT_ADD = 0, > + VHOST_SHARED_OBJECT_LOOKUP, > + VHOST_SHARED_OBJECT_REMOVE, > +} VhostUserSharedType; > + > +typedef struct VhostUserShared { > + unsigned char uuid[16]; > + VhostUserSharedType type; > + int dmabuf_fd; > +} VhostUserShared; > + > typedef struct { > VhostUserRequest request; > > @@ -214,6 +229,7 @@ typedef union { > VhostUserCryptoSession session; > VhostUserVringArea area; > VhostUserInflight inflight; > + VhostUserShared object; > } VhostUserPayload; > > typedef struct VhostUserMsg { > @@ -1582,6 +1598,52 @@ static int > vhost_user_slave_handle_vring_host_notifier(struct vhost_dev *dev, > return 0; > } > > +static int vhost_user_backend_handle_shared_object(VhostUserShared *object) > +{ > + QemuUUID uuid;
Can we initialize it here? uuid = { .data = object->uuid } ? Also, pls put space after variable declaration. > + memcpy(uuid.data, object->uuid, sizeof(object->uuid)); > + > + switch (object->type) { > + case VHOST_SHARED_OBJECT_ADD: > + return virtio_add_dmabuf(&uuid, object->dmabuf_fd); > + case VHOST_SHARED_OBJECT_LOOKUP: > + object->dmabuf_fd = virtio_lookup_dmabuf(&uuid); > + if (object->dmabuf_fd < 0) { > + return object->dmabuf_fd; > + } > + break; > + case VHOST_SHARED_OBJECT_REMOVE: > + return virtio_remove_resource(&uuid); > + } > + I couldn't figure out why, but if I commit this then run checkpatch, like this ./scripts/checkpatch.pl HEAD~1..HEAD then it is unhappy about the : in case. Any idea why? > + return 0; > +} > + > +static bool > +vhost_user_backend_send_dmabuf_fd(QIOChannel *ioc, VhostUserHeader *hdr, > + VhostUserPayload *payload) > +{ > + Error *local_err = NULL; > + struct iovec iov[2]; > + if (hdr->flags & VHOST_USER_NEED_REPLY_MASK) { > + hdr->flags &= ~VHOST_USER_NEED_REPLY_MASK; > + hdr->flags |= VHOST_USER_REPLY_MASK; > + > + hdr->size = sizeof(payload->object); > + > + iov[0].iov_base = hdr; > + iov[0].iov_len = VHOST_USER_HDR_SIZE; > + iov[1].iov_base = payload; > + iov[1].iov_len = hdr->size; > + > + if (qio_channel_writev_all(ioc, iov, ARRAY_SIZE(iov), &local_err)) { > + error_report_err(local_err); > + return false; > + } > + } > + return true; > +} > + > static void close_slave_channel(struct vhost_user *u) > { > g_source_destroy(u->slave_src); > @@ -1639,6 +1701,12 @@ static gboolean slave_read(QIOChannel *ioc, > GIOCondition condition, > ret = vhost_user_slave_handle_vring_host_notifier(dev, &payload.area, > fd ? fd[0] : -1); > break; > + case VHOST_USER_BACKEND_SHARED_OBJECT: > + ret = vhost_user_backend_handle_shared_object(&payload.object); > + if (!vhost_user_backend_send_dmabuf_fd(ioc, &hdr, &payload)) { > + goto err; > + } > + break; > default: > error_report("Received unexpected msg type: %d.", hdr.request); > ret = -EINVAL; > diff --git a/subprojects/libvhost-user/libvhost-user.c > b/subprojects/libvhost-user/libvhost-user.c > index 8fb61e2df2..27f16d292a 100644 > --- a/subprojects/libvhost-user/libvhost-user.c > +++ b/subprojects/libvhost-user/libvhost-user.c > @@ -1403,6 +1403,94 @@ bool vu_set_queue_host_notifier(VuDev *dev, VuVirtq > *vq, int fd, > return vu_process_message_reply(dev, &vmsg); > } > > +bool > +vu_get_shared_object(VuDev *dev, unsigned char uuid[UUID_LEN], int > *dmabuf_fd) > +{ > + bool result = false; > + VhostUserMsg msg_reply; > + VhostUserMsg msg = { > + .request = VHOST_USER_BACKEND_SHARED_OBJECT, > + .size = sizeof(msg.payload.object), > + .flags = VHOST_USER_VERSION | VHOST_USER_NEED_REPLY_MASK, > + .payload.object = { > + .type = VHOST_SHARED_OBJECT_LOOKUP, > + }, > + }; > + > + memcpy(msg.payload.object.uuid, uuid, sizeof(uuid[0]) * UUID_LEN); > + > + pthread_mutex_lock(&dev->slave_mutex); > + if (!vu_message_write(dev, dev->slave_fd, &msg)) { > + goto out; > + } > + > + if (!vu_message_read_default(dev, dev->slave_fd, &msg_reply)) { > + goto out; > + } > + > + if (msg_reply.request != msg.request) { > + DPRINT("Received unexpected msg type. Expected %d, received %d", > + msg.request, msg_reply.request); > + goto out; > + } > + > + *dmabuf_fd = msg_reply.payload.object.dmabuf_fd; > + result = *dmabuf_fd > 0; > +out: > + pthread_mutex_unlock(&dev->slave_mutex); > + > + return result; > +} > + > +static bool > +vu_send_message(VuDev *dev, VhostUserMsg *vmsg) > +{ > + bool result = false; > + pthread_mutex_lock(&dev->slave_mutex); > + if (!vu_message_write(dev, dev->slave_fd, vmsg)) { > + goto out; > + } > + > + result = true; > +out: > + pthread_mutex_unlock(&dev->slave_mutex); > + > + return result; > +} > + > +bool > +vu_add_shared_object(VuDev *dev, unsigned char uuid[UUID_LEN], int dmabuf_fd) > +{ > + VhostUserMsg msg = { > + .request = VHOST_USER_BACKEND_SHARED_OBJECT, > + .size = sizeof(msg.payload.object), > + .flags = VHOST_USER_VERSION, > + .payload.object = { > + .dmabuf_fd = dmabuf_fd, > + .type = VHOST_SHARED_OBJECT_ADD, > + }, > + }; > + memcpy(msg.payload.object.uuid, uuid, sizeof(uuid[0]) * UUID_LEN); > + > + return vu_send_message(dev, &msg); > +} > + > +bool > +vu_rm_shared_object(VuDev *dev, unsigned char uuid[UUID_LEN]) > +{ > + VhostUserMsg msg = { > + .request = VHOST_USER_BACKEND_SHARED_OBJECT, > + .size = sizeof(msg.payload.object), > + .flags = VHOST_USER_VERSION, > + .payload.object = { > + .type = VHOST_SHARED_OBJECT_REMOVE, > + }, > + }; > + memcpy(msg.payload.object.uuid, uuid, sizeof(uuid[0]) * UUID_LEN); > + > + return vu_send_message(dev, &msg); > +} > + > static bool > vu_set_vring_call_exec(VuDev *dev, VhostUserMsg *vmsg) > { > diff --git a/subprojects/libvhost-user/libvhost-user.h > b/subprojects/libvhost-user/libvhost-user.h > index 49208cceaa..a43d115bd7 100644 > --- a/subprojects/libvhost-user/libvhost-user.h > +++ b/subprojects/libvhost-user/libvhost-user.h > @@ -119,6 +119,7 @@ typedef enum VhostUserSlaveRequest { > VHOST_USER_BACKEND_VRING_HOST_NOTIFIER_MSG = 3, > VHOST_USER_BACKEND_VRING_CALL = 4, > VHOST_USER_BACKEND_VRING_ERR = 5, > + VHOST_USER_BACKEND_SHARED_OBJECT = 6, > VHOST_USER_BACKEND_MAX > } VhostUserSlaveRequest; > > @@ -172,6 +173,20 @@ typedef struct VhostUserInflight { > uint16_t queue_size; > } VhostUserInflight; > > +typedef enum VhostUserSharedType { > + VHOST_SHARED_OBJECT_ADD = 0, > + VHOST_SHARED_OBJECT_LOOKUP, > + VHOST_SHARED_OBJECT_REMOVE, > +} VhostUserSharedType; > + > +#define UUID_LEN 16 > + > +typedef struct VhostUserShared { > + unsigned char uuid[UUID_LEN]; > + VhostUserSharedType type; > + int dmabuf_fd; > +} VhostUserShared; > + > #if defined(_WIN32) && (defined(__x86_64__) || defined(__i386__)) > # define VU_PACKED __attribute__((gcc_struct, packed)) > #else > @@ -199,6 +214,7 @@ typedef struct VhostUserMsg { > VhostUserConfig config; > VhostUserVringArea area; > VhostUserInflight inflight; > + VhostUserShared object; > } payload; > > int fds[VHOST_MEMORY_BASELINE_NREGIONS]; > @@ -539,6 +555,46 @@ void vu_set_queue_handler(VuDev *dev, VuVirtq *vq, > bool vu_set_queue_host_notifier(VuDev *dev, VuVirtq *vq, int fd, > int size, int offset); > > +/** > + * vu_get_shared_object: > + * @dev: a VuDev context > + * @uuid: UUID of the shared object > + * @dmabuf_fd: output dma-buf file descriptor > + * > + * Lookup for a virtio shared object (i.e., dma-buf fd) associated with the > + * received UUID. Result, if found, is stored in the dmabuf_fd argument. > + * > + * Returns: whether the virtio object was found. > + */ > +bool vu_get_shared_object(VuDev *dev, unsigned char uuid[UUID_LEN], > + int *dmabuf_fd); > + > +/** > + * vu_add_shared_object: > + * @dev: a VuDev context > + * @uuid: UUID of the shared object > + * @dmabuf_fd: output dma-buf file descriptor > + * > + * Stores a new shared object (i.e., dma-buf fd) in the hash table, and > + * associates it with the received UUID. > + * > + * Returns: TRUE on success, FALSE on failure. > + */ > +bool vu_add_shared_object(VuDev *dev, unsigned char uuid[UUID_LEN], > + int dmabuf_fd); > + > +/** > + * vu_rm_shared_object: > + * @dev: a VuDev context > + * @uuid: UUID of the shared object > + * > + * Removes a shared object (i.e., dma-buf fd) associated with the > + * received UUID from the hash table. > + * > + * Returns: TRUE on success, FALSE on failure. > + */ > +bool vu_rm_shared_object(VuDev *dev, unsigned char uuid[UUID_LEN]); > + > /** > * vu_queue_set_notification: > * @dev: a VuDev context > -- > 2.40.0