X-Git-Url: https://gerrit.opnfv.org/gerrit/gitweb?a=blobdiff_plain;f=qemu%2Fhw%2Fvirtio%2Fvhost-user.c;h=5914e85107011ec03373f1bbb86aec7d2120da97;hb=a14b48d18a9ed03ec191cf16b162206998a895ce;hp=e7ab8293d1b842a6b0c76c52cd0da28394ac692b;hpb=e44e3482bdb4d0ebde2d8b41830ac2cdb07948fb;p=kvmfornfv.git diff --git a/qemu/hw/virtio/vhost-user.c b/qemu/hw/virtio/vhost-user.c index e7ab8293d..5914e8510 100644 --- a/qemu/hw/virtio/vhost-user.c +++ b/qemu/hw/virtio/vhost-user.c @@ -8,22 +8,35 @@ * */ +#include "qemu/osdep.h" +#include "qapi/error.h" #include "hw/virtio/vhost.h" #include "hw/virtio/vhost-backend.h" +#include "hw/virtio/virtio-net.h" #include "sysemu/char.h" #include "sysemu/kvm.h" #include "qemu/error-report.h" #include "qemu/sockets.h" #include "exec/ram_addr.h" +#include "migration/migration.h" -#include -#include #include #include #include #include #define VHOST_MEMORY_MAX_NREGIONS 8 +#define VHOST_USER_F_PROTOCOL_FEATURES 30 + +enum VhostUserProtocolFeature { + VHOST_USER_PROTOCOL_F_MQ = 0, + VHOST_USER_PROTOCOL_F_LOG_SHMFD = 1, + VHOST_USER_PROTOCOL_F_RARP = 2, + + VHOST_USER_PROTOCOL_F_MAX +}; + +#define VHOST_USER_PROTOCOL_FEATURE_MASK ((1 << VHOST_USER_PROTOCOL_F_MAX) - 1) typedef enum VhostUserRequest { VHOST_USER_NONE = 0, @@ -41,6 +54,11 @@ typedef enum VhostUserRequest { VHOST_USER_SET_VRING_KICK = 12, VHOST_USER_SET_VRING_CALL = 13, VHOST_USER_SET_VRING_ERR = 14, + VHOST_USER_GET_PROTOCOL_FEATURES = 15, + VHOST_USER_SET_PROTOCOL_FEATURES = 16, + VHOST_USER_GET_QUEUE_NUM = 17, + VHOST_USER_SET_VRING_ENABLE = 18, + VHOST_USER_SEND_RARP = 19, VHOST_USER_MAX } VhostUserRequest; @@ -57,6 +75,11 @@ typedef struct VhostUserMemory { VhostUserMemoryRegion regions[VHOST_MEMORY_MAX_NREGIONS]; } VhostUserMemory; +typedef struct VhostUserLog { + uint64_t mmap_size; + uint64_t mmap_offset; +} VhostUserLog; + typedef struct VhostUserMsg { VhostUserRequest request; @@ -71,7 +94,8 @@ typedef struct VhostUserMsg { struct vhost_vring_state state; struct vhost_vring_addr addr; VhostUserMemory memory; - }; + VhostUserLog log; + } payload; } QEMU_PACKED VhostUserMsg; static VhostUserMsg m __attribute__ ((unused)); @@ -89,37 +113,6 @@ static bool ioeventfd_enabled(void) return kvm_enabled() && kvm_eventfds_enabled(); } -static unsigned long int ioctl_to_vhost_user_request[VHOST_USER_MAX] = { - -1, /* VHOST_USER_NONE */ - VHOST_GET_FEATURES, /* VHOST_USER_GET_FEATURES */ - VHOST_SET_FEATURES, /* VHOST_USER_SET_FEATURES */ - VHOST_SET_OWNER, /* VHOST_USER_SET_OWNER */ - VHOST_RESET_OWNER, /* VHOST_USER_RESET_OWNER */ - VHOST_SET_MEM_TABLE, /* VHOST_USER_SET_MEM_TABLE */ - VHOST_SET_LOG_BASE, /* VHOST_USER_SET_LOG_BASE */ - VHOST_SET_LOG_FD, /* VHOST_USER_SET_LOG_FD */ - VHOST_SET_VRING_NUM, /* VHOST_USER_SET_VRING_NUM */ - VHOST_SET_VRING_ADDR, /* VHOST_USER_SET_VRING_ADDR */ - VHOST_SET_VRING_BASE, /* VHOST_USER_SET_VRING_BASE */ - VHOST_GET_VRING_BASE, /* VHOST_USER_GET_VRING_BASE */ - VHOST_SET_VRING_KICK, /* VHOST_USER_SET_VRING_KICK */ - VHOST_SET_VRING_CALL, /* VHOST_USER_SET_VRING_CALL */ - VHOST_SET_VRING_ERR /* VHOST_USER_SET_VRING_ERR */ -}; - -static VhostUserRequest vhost_user_request_translate(unsigned long int request) -{ - VhostUserRequest idx; - - for (idx = 0; idx < VHOST_USER_MAX; idx++) { - if (ioctl_to_vhost_user_request[idx] == request) { - break; - } - } - - return (idx == VHOST_USER_MAX) ? VHOST_USER_NONE : idx; -} - static int vhost_user_read(struct vhost_dev *dev, VhostUserMsg *msg) { CharDriverState *chr = dev->opaque; @@ -128,8 +121,8 @@ static int vhost_user_read(struct vhost_dev *dev, VhostUserMsg *msg) r = qemu_chr_fe_read_all(chr, p, size); if (r != size) { - error_report("Failed to read msg header. Read %d instead of %d.", r, - size); + error_report("Failed to read msg header. Read %d instead of %d." + " Original request %d.", r, size, msg->request); goto fail; } @@ -166,12 +159,35 @@ fail: return -1; } +static bool vhost_user_one_time_request(VhostUserRequest request) +{ + switch (request) { + case VHOST_USER_SET_OWNER: + case VHOST_USER_RESET_OWNER: + case VHOST_USER_SET_MEM_TABLE: + case VHOST_USER_GET_QUEUE_NUM: + return true; + default: + return false; + } +} + +/* most non-init callers ignore the error */ static int vhost_user_write(struct vhost_dev *dev, VhostUserMsg *msg, int *fds, int fd_num) { CharDriverState *chr = dev->opaque; int size = VHOST_USER_HDR_SIZE + msg->size; + /* + * For non-vring specific requests, like VHOST_USER_SET_MEM_TABLE, + * we just need send it once in the first time. For later such + * request, we just ignore it. + */ + if (vhost_user_one_time_request(msg->request) && dev->vq_index != 0) { + return 0; + } + if (fd_num) { qemu_chr_fe_set_msgfds(chr, fds, fd_num); } @@ -180,157 +196,364 @@ static int vhost_user_write(struct vhost_dev *dev, VhostUserMsg *msg, 0 : -1; } -static int vhost_user_call(struct vhost_dev *dev, unsigned long int request, - void *arg) +static int vhost_user_set_log_base(struct vhost_dev *dev, uint64_t base, + struct vhost_log *log) { - VhostUserMsg msg; - VhostUserRequest msg_request; - struct vhost_vring_file *file = 0; - int need_reply = 0; int fds[VHOST_MEMORY_MAX_NREGIONS]; - int i, fd; size_t fd_num = 0; + bool shmfd = virtio_has_feature(dev->protocol_features, + VHOST_USER_PROTOCOL_F_LOG_SHMFD); + VhostUserMsg msg = { + .request = VHOST_USER_SET_LOG_BASE, + .flags = VHOST_USER_VERSION, + .payload.log.mmap_size = log->size * sizeof(*(log->log)), + .payload.log.mmap_offset = 0, + .size = sizeof(msg.payload.log), + }; - assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER); + if (shmfd && log->fd != -1) { + fds[fd_num++] = log->fd; + } - msg_request = vhost_user_request_translate(request); - msg.request = msg_request; - msg.flags = VHOST_USER_VERSION; - msg.size = 0; + vhost_user_write(dev, &msg, fds, fd_num); - switch (request) { - case VHOST_GET_FEATURES: - need_reply = 1; - break; - - case VHOST_SET_FEATURES: - case VHOST_SET_LOG_BASE: - msg.u64 = *((__u64 *) arg); - msg.size = sizeof(m.u64); - break; - - case VHOST_SET_OWNER: - case VHOST_RESET_OWNER: - break; - - case VHOST_SET_MEM_TABLE: - for (i = 0; i < dev->mem->nregions; ++i) { - struct vhost_memory_region *reg = dev->mem->regions + i; - ram_addr_t ram_addr; - - assert((uintptr_t)reg->userspace_addr == reg->userspace_addr); - qemu_ram_addr_from_host((void *)(uintptr_t)reg->userspace_addr, &ram_addr); - fd = qemu_get_ram_fd(ram_addr); - if (fd > 0) { - msg.memory.regions[fd_num].userspace_addr = reg->userspace_addr; - msg.memory.regions[fd_num].memory_size = reg->memory_size; - msg.memory.regions[fd_num].guest_phys_addr = reg->guest_phys_addr; - msg.memory.regions[fd_num].mmap_offset = reg->userspace_addr - - (uintptr_t) qemu_get_ram_block_host_ptr(ram_addr); - assert(fd_num < VHOST_MEMORY_MAX_NREGIONS); - fds[fd_num++] = fd; - } + if (shmfd) { + msg.size = 0; + if (vhost_user_read(dev, &msg) < 0) { + return 0; } - msg.memory.nregions = fd_num; - - if (!fd_num) { - error_report("Failed initializing vhost-user memory map, " - "consider using -object memory-backend-file share=on"); + if (msg.request != VHOST_USER_SET_LOG_BASE) { + error_report("Received unexpected msg type. " + "Expected %d received %d", + VHOST_USER_SET_LOG_BASE, msg.request); return -1; } + } - msg.size = sizeof(m.memory.nregions); - msg.size += sizeof(m.memory.padding); - msg.size += fd_num * sizeof(VhostUserMemoryRegion); - - break; - - case VHOST_SET_LOG_FD: - fds[fd_num++] = *((int *) arg); - break; - - case VHOST_SET_VRING_NUM: - case VHOST_SET_VRING_BASE: - memcpy(&msg.state, arg, sizeof(struct vhost_vring_state)); - msg.size = sizeof(m.state); - break; - - case VHOST_GET_VRING_BASE: - memcpy(&msg.state, arg, sizeof(struct vhost_vring_state)); - msg.size = sizeof(m.state); - need_reply = 1; - break; - - case VHOST_SET_VRING_ADDR: - memcpy(&msg.addr, arg, sizeof(struct vhost_vring_addr)); - msg.size = sizeof(m.addr); - break; - - case VHOST_SET_VRING_KICK: - case VHOST_SET_VRING_CALL: - case VHOST_SET_VRING_ERR: - file = arg; - msg.u64 = file->index & VHOST_USER_VRING_IDX_MASK; - msg.size = sizeof(m.u64); - if (ioeventfd_enabled() && file->fd > 0) { - fds[fd_num++] = file->fd; - } else { - msg.u64 |= VHOST_USER_VRING_NOFD_MASK; + return 0; +} + +static int vhost_user_set_mem_table(struct vhost_dev *dev, + struct vhost_memory *mem) +{ + int fds[VHOST_MEMORY_MAX_NREGIONS]; + int i, fd; + size_t fd_num = 0; + VhostUserMsg msg = { + .request = VHOST_USER_SET_MEM_TABLE, + .flags = VHOST_USER_VERSION, + }; + + for (i = 0; i < dev->mem->nregions; ++i) { + struct vhost_memory_region *reg = dev->mem->regions + i; + ram_addr_t ram_addr; + + assert((uintptr_t)reg->userspace_addr == reg->userspace_addr); + qemu_ram_addr_from_host((void *)(uintptr_t)reg->userspace_addr, + &ram_addr); + fd = qemu_get_ram_fd(ram_addr); + if (fd > 0) { + msg.payload.memory.regions[fd_num].userspace_addr = reg->userspace_addr; + msg.payload.memory.regions[fd_num].memory_size = reg->memory_size; + msg.payload.memory.regions[fd_num].guest_phys_addr = reg->guest_phys_addr; + msg.payload.memory.regions[fd_num].mmap_offset = reg->userspace_addr - + (uintptr_t) qemu_get_ram_block_host_ptr(ram_addr); + assert(fd_num < VHOST_MEMORY_MAX_NREGIONS); + fds[fd_num++] = fd; } - break; - default: - error_report("vhost-user trying to send unhandled ioctl"); + } + + msg.payload.memory.nregions = fd_num; + + if (!fd_num) { + error_report("Failed initializing vhost-user memory map, " + "consider using -object memory-backend-file share=on"); return -1; - break; } - if (vhost_user_write(dev, &msg, fds, fd_num) < 0) { + msg.size = sizeof(msg.payload.memory.nregions); + msg.size += sizeof(msg.payload.memory.padding); + msg.size += fd_num * sizeof(VhostUserMemoryRegion); + + vhost_user_write(dev, &msg, fds, fd_num); + + return 0; +} + +static int vhost_user_set_vring_addr(struct vhost_dev *dev, + struct vhost_vring_addr *addr) +{ + VhostUserMsg msg = { + .request = VHOST_USER_SET_VRING_ADDR, + .flags = VHOST_USER_VERSION, + .payload.addr = *addr, + .size = sizeof(msg.payload.addr), + }; + + vhost_user_write(dev, &msg, NULL, 0); + + return 0; +} + +static int vhost_user_set_vring_endian(struct vhost_dev *dev, + struct vhost_vring_state *ring) +{ + error_report("vhost-user trying to send unhandled ioctl"); + return -1; +} + +static int vhost_set_vring(struct vhost_dev *dev, + unsigned long int request, + struct vhost_vring_state *ring) +{ + VhostUserMsg msg = { + .request = request, + .flags = VHOST_USER_VERSION, + .payload.state = *ring, + .size = sizeof(msg.payload.state), + }; + + vhost_user_write(dev, &msg, NULL, 0); + + return 0; +} + +static int vhost_user_set_vring_num(struct vhost_dev *dev, + struct vhost_vring_state *ring) +{ + return vhost_set_vring(dev, VHOST_USER_SET_VRING_NUM, ring); +} + +static int vhost_user_set_vring_base(struct vhost_dev *dev, + struct vhost_vring_state *ring) +{ + return vhost_set_vring(dev, VHOST_USER_SET_VRING_BASE, ring); +} + +static int vhost_user_set_vring_enable(struct vhost_dev *dev, int enable) +{ + int i; + + if (!virtio_has_feature(dev->features, VHOST_USER_F_PROTOCOL_FEATURES)) { + return -1; + } + + for (i = 0; i < dev->nvqs; ++i) { + struct vhost_vring_state state = { + .index = dev->vq_index + i, + .num = enable, + }; + + vhost_set_vring(dev, VHOST_USER_SET_VRING_ENABLE, &state); + } + + return 0; +} + +static int vhost_user_get_vring_base(struct vhost_dev *dev, + struct vhost_vring_state *ring) +{ + VhostUserMsg msg = { + .request = VHOST_USER_GET_VRING_BASE, + .flags = VHOST_USER_VERSION, + .payload.state = *ring, + .size = sizeof(msg.payload.state), + }; + + vhost_user_write(dev, &msg, NULL, 0); + + if (vhost_user_read(dev, &msg) < 0) { return 0; } - if (need_reply) { - if (vhost_user_read(dev, &msg) < 0) { - return 0; - } + if (msg.request != VHOST_USER_GET_VRING_BASE) { + error_report("Received unexpected msg type. Expected %d received %d", + VHOST_USER_GET_VRING_BASE, msg.request); + return -1; + } - if (msg_request != msg.request) { - error_report("Received unexpected msg type." - " Expected %d received %d", msg_request, msg.request); - return -1; - } + if (msg.size != sizeof(msg.payload.state)) { + error_report("Received bad msg size."); + return -1; + } - switch (msg_request) { - case VHOST_USER_GET_FEATURES: - if (msg.size != sizeof(m.u64)) { - error_report("Received bad msg size."); - return -1; - } - *((__u64 *) arg) = msg.u64; - break; - case VHOST_USER_GET_VRING_BASE: - if (msg.size != sizeof(m.state)) { - error_report("Received bad msg size."); - return -1; - } - memcpy(arg, &msg.state, sizeof(struct vhost_vring_state)); - break; - default: - error_report("Received unexpected msg type."); - return -1; - break; - } + *ring = msg.payload.state; + + return 0; +} + +static int vhost_set_vring_file(struct vhost_dev *dev, + VhostUserRequest request, + struct vhost_vring_file *file) +{ + int fds[VHOST_MEMORY_MAX_NREGIONS]; + size_t fd_num = 0; + VhostUserMsg msg = { + .request = request, + .flags = VHOST_USER_VERSION, + .payload.u64 = file->index & VHOST_USER_VRING_IDX_MASK, + .size = sizeof(msg.payload.u64), + }; + + if (ioeventfd_enabled() && file->fd > 0) { + fds[fd_num++] = file->fd; + } else { + msg.payload.u64 |= VHOST_USER_VRING_NOFD_MASK; } + vhost_user_write(dev, &msg, fds, fd_num); + + return 0; +} + +static int vhost_user_set_vring_kick(struct vhost_dev *dev, + struct vhost_vring_file *file) +{ + return vhost_set_vring_file(dev, VHOST_USER_SET_VRING_KICK, file); +} + +static int vhost_user_set_vring_call(struct vhost_dev *dev, + struct vhost_vring_file *file) +{ + return vhost_set_vring_file(dev, VHOST_USER_SET_VRING_CALL, file); +} + +static int vhost_user_set_u64(struct vhost_dev *dev, int request, uint64_t u64) +{ + VhostUserMsg msg = { + .request = request, + .flags = VHOST_USER_VERSION, + .payload.u64 = u64, + .size = sizeof(msg.payload.u64), + }; + + vhost_user_write(dev, &msg, NULL, 0); + + return 0; +} + +static int vhost_user_set_features(struct vhost_dev *dev, + uint64_t features) +{ + return vhost_user_set_u64(dev, VHOST_USER_SET_FEATURES, features); +} + +static int vhost_user_set_protocol_features(struct vhost_dev *dev, + uint64_t features) +{ + return vhost_user_set_u64(dev, VHOST_USER_SET_PROTOCOL_FEATURES, features); +} + +static int vhost_user_get_u64(struct vhost_dev *dev, int request, uint64_t *u64) +{ + VhostUserMsg msg = { + .request = request, + .flags = VHOST_USER_VERSION, + }; + + if (vhost_user_one_time_request(request) && dev->vq_index != 0) { + return 0; + } + + vhost_user_write(dev, &msg, NULL, 0); + + if (vhost_user_read(dev, &msg) < 0) { + return 0; + } + + if (msg.request != request) { + error_report("Received unexpected msg type. Expected %d received %d", + request, msg.request); + return -1; + } + + if (msg.size != sizeof(msg.payload.u64)) { + error_report("Received bad msg size."); + return -1; + } + + *u64 = msg.payload.u64; + + return 0; +} + +static int vhost_user_get_features(struct vhost_dev *dev, uint64_t *features) +{ + return vhost_user_get_u64(dev, VHOST_USER_GET_FEATURES, features); +} + +static int vhost_user_set_owner(struct vhost_dev *dev) +{ + VhostUserMsg msg = { + .request = VHOST_USER_SET_OWNER, + .flags = VHOST_USER_VERSION, + }; + + vhost_user_write(dev, &msg, NULL, 0); + + return 0; +} + +static int vhost_user_reset_device(struct vhost_dev *dev) +{ + VhostUserMsg msg = { + .request = VHOST_USER_RESET_OWNER, + .flags = VHOST_USER_VERSION, + }; + + vhost_user_write(dev, &msg, NULL, 0); + return 0; } static int vhost_user_init(struct vhost_dev *dev, void *opaque) { + uint64_t features; + int err; + assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER); dev->opaque = opaque; + err = vhost_user_get_features(dev, &features); + if (err < 0) { + return err; + } + + if (virtio_has_feature(features, VHOST_USER_F_PROTOCOL_FEATURES)) { + dev->backend_features |= 1ULL << VHOST_USER_F_PROTOCOL_FEATURES; + + err = vhost_user_get_u64(dev, VHOST_USER_GET_PROTOCOL_FEATURES, + &features); + if (err < 0) { + return err; + } + + dev->protocol_features = features & VHOST_USER_PROTOCOL_FEATURE_MASK; + err = vhost_user_set_protocol_features(dev, dev->protocol_features); + if (err < 0) { + return err; + } + + /* query the max queues we support if backend supports Multiple Queue */ + if (dev->protocol_features & (1ULL << VHOST_USER_PROTOCOL_F_MQ)) { + err = vhost_user_get_u64(dev, VHOST_USER_GET_QUEUE_NUM, + &dev->max_queues); + if (err < 0) { + return err; + } + } + } + + if (dev->migration_blocker == NULL && + !virtio_has_feature(dev->protocol_features, + VHOST_USER_PROTOCOL_F_LOG_SHMFD)) { + error_setg(&dev->migration_blocker, + "Migration disabled: vhost-user backend lacks " + "VHOST_USER_PROTOCOL_F_LOG_SHMFD feature."); + } + return 0; } @@ -343,9 +566,92 @@ static int vhost_user_cleanup(struct vhost_dev *dev) return 0; } +static int vhost_user_get_vq_index(struct vhost_dev *dev, int idx) +{ + assert(idx >= dev->vq_index && idx < dev->vq_index + dev->nvqs); + + return idx; +} + +static int vhost_user_memslots_limit(struct vhost_dev *dev) +{ + return VHOST_MEMORY_MAX_NREGIONS; +} + +static bool vhost_user_requires_shm_log(struct vhost_dev *dev) +{ + assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER); + + return virtio_has_feature(dev->protocol_features, + VHOST_USER_PROTOCOL_F_LOG_SHMFD); +} + +static int vhost_user_migration_done(struct vhost_dev *dev, char* mac_addr) +{ + VhostUserMsg msg = { 0 }; + int err; + + assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER); + + /* If guest supports GUEST_ANNOUNCE do nothing */ + if (virtio_has_feature(dev->acked_features, VIRTIO_NET_F_GUEST_ANNOUNCE)) { + return 0; + } + + /* if backend supports VHOST_USER_PROTOCOL_F_RARP ask it to send the RARP */ + if (virtio_has_feature(dev->protocol_features, + VHOST_USER_PROTOCOL_F_RARP)) { + msg.request = VHOST_USER_SEND_RARP; + msg.flags = VHOST_USER_VERSION; + memcpy((char *)&msg.payload.u64, mac_addr, 6); + msg.size = sizeof(msg.payload.u64); + + err = vhost_user_write(dev, &msg, NULL, 0); + return err; + } + return -1; +} + +static bool vhost_user_can_merge(struct vhost_dev *dev, + uint64_t start1, uint64_t size1, + uint64_t start2, uint64_t size2) +{ + ram_addr_t ram_addr; + int mfd, rfd; + MemoryRegion *mr; + + mr = qemu_ram_addr_from_host((void *)(uintptr_t)start1, &ram_addr); + assert(mr); + mfd = qemu_get_ram_fd(ram_addr); + + mr = qemu_ram_addr_from_host((void *)(uintptr_t)start2, &ram_addr); + assert(mr); + rfd = qemu_get_ram_fd(ram_addr); + + return mfd == rfd; +} + const VhostOps user_ops = { .backend_type = VHOST_BACKEND_TYPE_USER, - .vhost_call = vhost_user_call, .vhost_backend_init = vhost_user_init, - .vhost_backend_cleanup = vhost_user_cleanup - }; + .vhost_backend_cleanup = vhost_user_cleanup, + .vhost_backend_memslots_limit = vhost_user_memslots_limit, + .vhost_set_log_base = vhost_user_set_log_base, + .vhost_set_mem_table = vhost_user_set_mem_table, + .vhost_set_vring_addr = vhost_user_set_vring_addr, + .vhost_set_vring_endian = vhost_user_set_vring_endian, + .vhost_set_vring_num = vhost_user_set_vring_num, + .vhost_set_vring_base = vhost_user_set_vring_base, + .vhost_get_vring_base = vhost_user_get_vring_base, + .vhost_set_vring_kick = vhost_user_set_vring_kick, + .vhost_set_vring_call = vhost_user_set_vring_call, + .vhost_set_features = vhost_user_set_features, + .vhost_get_features = vhost_user_get_features, + .vhost_set_owner = vhost_user_set_owner, + .vhost_reset_device = vhost_user_reset_device, + .vhost_get_vq_index = vhost_user_get_vq_index, + .vhost_set_vring_enable = vhost_user_set_vring_enable, + .vhost_requires_shm_log = vhost_user_requires_shm_log, + .vhost_migration_done = vhost_user_migration_done, + .vhost_backend_can_merge = vhost_user_can_merge, +};