diff options
| -rw-r--r-- | epoll_type.h | 2 | ||||
| -rw-r--r-- | passt.c | 4 | ||||
| -rw-r--r-- | vhost_user.c | 81 | ||||
| -rw-r--r-- | virtio.h | 2 | ||||
| -rw-r--r-- | vu_common.c | 49 | ||||
| -rw-r--r-- | vu_common.h | 1 |
6 files changed, 138 insertions, 1 deletions
diff --git a/epoll_type.h b/epoll_type.h index f3ef415..fd9eac3 100644 --- a/epoll_type.h +++ b/epoll_type.h @@ -40,6 +40,8 @@ enum epoll_type { EPOLL_TYPE_VHOST_CMD, /* vhost-user kick event socket */ EPOLL_TYPE_VHOST_KICK, + /* vhost-user migration socket */ + EPOLL_TYPE_VHOST_MIGRATION, EPOLL_NUM_TYPES, }; @@ -75,6 +75,7 @@ char *epoll_type_str[] = { [EPOLL_TYPE_TAP_LISTEN] = "listening qemu socket", [EPOLL_TYPE_VHOST_CMD] = "vhost-user command socket", [EPOLL_TYPE_VHOST_KICK] = "vhost-user kick socket", + [EPOLL_TYPE_VHOST_MIGRATION] = "vhost-user migration socket", }; static_assert(ARRAY_SIZE(epoll_type_str) == EPOLL_NUM_TYPES, "epoll_type_str[] doesn't match enum epoll_type"); @@ -356,6 +357,9 @@ loop: case EPOLL_TYPE_VHOST_KICK: vu_kick_cb(c.vdev, ref, &now); break; + case EPOLL_TYPE_VHOST_MIGRATION: + vu_migrate(c.vdev, eventmask); + break; default: /* Can't happen */ ASSERT(0); diff --git a/vhost_user.c b/vhost_user.c index 90c46d5..11b0b44 100644 --- a/vhost_user.c +++ b/vhost_user.c @@ -982,6 +982,78 @@ static bool vu_set_vring_enable_exec(struct vu_dev *vdev, } /** + * vu_set_migration_watch() -- Add the migration file descriptor to + * to the passt epoll file descriptor + * @vdev: vhost-user device + * @fd: File descriptor to add + * @direction: Direction of the migration (save or load backend state) + */ +static void vu_set_migration_watch(const struct vu_dev *vdev, int fd, + int direction) +{ + union epoll_ref ref = { + .type = EPOLL_TYPE_VHOST_MIGRATION, + .fd = fd, + }; + struct epoll_event ev = { 0 }; + + ev.data.u64 = ref.u64; + switch (direction) { + case VHOST_USER_TRANSFER_STATE_DIRECTION_SAVE: + ev.events = EPOLLOUT; + break; + case VHOST_USER_TRANSFER_STATE_DIRECTION_LOAD: + ev.events = EPOLLIN; + break; + default: + ASSERT(0); + } + + epoll_ctl(vdev->context->epollfd, EPOLL_CTL_ADD, ref.fd, &ev); +} + +/** + * vu_set_device_state_fd_exec() -- Set the device state migration channel + * @vdev: vhost-user device + * @vmsg: vhost-user message + * + * Return: True as the reply contains 0 to indicate success + * and set bit 8 as we don't provide our own fd. + */ +static bool vu_set_device_state_fd_exec(struct vu_dev *vdev, + struct vhost_user_msg *msg) +{ + unsigned int direction = msg->payload.transfer_state.direction; + unsigned int phase = msg->payload.transfer_state.phase; + + if (msg->fd_num != 1) + die("Invalid device_state_fd message"); + + if (phase != VHOST_USER_TRANSFER_STATE_PHASE_STOPPED) + die("Invalid device_state_fd phase: %d", phase); + + if (direction != VHOST_USER_TRANSFER_STATE_DIRECTION_SAVE && + direction != VHOST_USER_TRANSFER_STATE_DIRECTION_LOAD) + die("Invalide device_state_fd direction: %d", direction); + + if (vdev->device_state_fd != -1) { + vu_remove_watch(vdev, vdev->device_state_fd); + close(vdev->device_state_fd); + } + + vdev->device_state_fd = msg->fds[0]; + vdev->device_state_result = -1; + vu_set_migration_watch(vdev, vdev->device_state_fd, direction); + + debug("Got device_state_fd: %d", vdev->device_state_fd); + + /* We don't provide a new fd for the data transfer */ + vmsg_set_reply_u64(msg, VHOST_USER_VRING_NOFD_MASK); + + return true; +} + +/** * vu_check_device_state_exec() -- Return device state migration result * @vdev: vhost-user device * @vmsg: vhost-user message @@ -1019,6 +1091,7 @@ void vu_init(struct ctx *c) } c->vdev->log_table = NULL; c->vdev->log_call_fd = -1; + c->vdev->device_state_fd = -1; c->vdev->device_state_result = -1; } @@ -1069,7 +1142,12 @@ void vu_cleanup(struct vu_dev *vdev) vu_close_log(vdev); - vdev->device_state_result = -1; + if (vdev->device_state_fd != -1) { + vu_remove_watch(vdev, vdev->device_state_fd); + close(vdev->device_state_fd); + vdev->device_state_fd = -1; + vdev->device_state_result = -1; + } } /** @@ -1100,6 +1178,7 @@ static bool (*vu_handle[VHOST_USER_MAX])(struct vu_dev *vdev, [VHOST_USER_SET_VRING_CALL] = vu_set_vring_call_exec, [VHOST_USER_SET_VRING_ERR] = vu_set_vring_err_exec, [VHOST_USER_SET_VRING_ENABLE] = vu_set_vring_enable_exec, + [VHOST_USER_SET_DEVICE_STATE_FD] = vu_set_device_state_fd_exec, [VHOST_USER_CHECK_DEVICE_STATE] = vu_check_device_state_exec, }; @@ -106,6 +106,7 @@ struct vu_dev_region { * @log_call_fd: Eventfd to report logging update * @log_size: Size of the logging memory region * @log_table: Base of the logging memory region + * @device_state_fd: Device state migration channel * @device_state_result: Device state migration result */ struct vu_dev { @@ -118,6 +119,7 @@ struct vu_dev { int log_call_fd; uint64_t log_size; uint8_t *log_table; + int device_state_fd; int device_state_result; }; diff --git a/vu_common.c b/vu_common.c index 16e7e76..3142b58 100644 --- a/vu_common.c +++ b/vu_common.c @@ -281,3 +281,52 @@ err: return -1; } + +/** + * vu_migrate() -- Send/receive passt insternal state to/from QEMU + * @vdev: vhost-user device + * @events: epoll events + */ +void vu_migrate(struct vu_dev *vdev, uint32_t events) +{ + int ret; + + /* TODO: collect/set passt internal state + * and use vdev->device_state_fd to send/receive it + */ + debug("vu_migrate fd %d events %x", vdev->device_state_fd, events); + if (events & EPOLLOUT) { + debug("Saving backend state"); + + /* send some stuff */ + ret = write(vdev->device_state_fd, "PASST", 6); + /* value to be returned by VHOST_USER_CHECK_DEVICE_STATE */ + vdev->device_state_result = ret == -1 ? -1 : 0; + /* Closing the file descriptor signals the end of transfer */ + epoll_ctl(vdev->context->epollfd, EPOLL_CTL_DEL, + vdev->device_state_fd, NULL); + close(vdev->device_state_fd); + vdev->device_state_fd = -1; + } else if (events & EPOLLIN) { + char buf[6]; + + debug("Loading backend state"); + /* read some stuff */ + ret = read(vdev->device_state_fd, buf, sizeof(buf)); + /* value to be returned by VHOST_USER_CHECK_DEVICE_STATE */ + if (ret != sizeof(buf)) { + vdev->device_state_result = -1; + } else { + ret = strncmp(buf, "PASST", sizeof(buf)); + vdev->device_state_result = ret == 0 ? 0 : -1; + } + } else if (events & EPOLLHUP) { + debug("Closing migration channel"); + + /* The end of file signals the end of the transfer. */ + epoll_ctl(vdev->context->epollfd, EPOLL_CTL_DEL, + vdev->device_state_fd, NULL); + close(vdev->device_state_fd); + vdev->device_state_fd = -1; + } +} diff --git a/vu_common.h b/vu_common.h index bd70faf..d56c021 100644 --- a/vu_common.h +++ b/vu_common.h @@ -57,4 +57,5 @@ void vu_flush(const struct vu_dev *vdev, struct vu_virtq *vq, void vu_kick_cb(struct vu_dev *vdev, union epoll_ref ref, const struct timespec *now); int vu_send_single(const struct ctx *c, const void *buf, size_t size); +void vu_migrate(struct vu_dev *vdev, uint32_t events); #endif /* VU_COMMON_H */ |