diff options
Diffstat (limited to 'subprojects/libvhost-user/libvhost-user.c')
| -rw-r--r-- | subprojects/libvhost-user/libvhost-user.c | 2883 |
1 files changed, 2883 insertions, 0 deletions
diff --git a/subprojects/libvhost-user/libvhost-user.c b/subprojects/libvhost-user/libvhost-user.c new file mode 100644 index 0000000000..fab7ca17ee --- /dev/null +++ b/subprojects/libvhost-user/libvhost-user.c @@ -0,0 +1,2883 @@ +/* + * Vhost User library + * + * Copyright IBM, Corp. 2007 + * Copyright (c) 2016 Red Hat, Inc. + * + * Authors: + * Anthony Liguori <aliguori@us.ibm.com> + * Marc-AndrĂ© Lureau <mlureau@redhat.com> + * Victor Kaplansky <victork@redhat.com> + * + * This work is licensed under the terms of the GNU GPL, version 2 or + * later. See the COPYING file in the top-level directory. + */ + +/* this code avoids GLib dependency */ +#include <stdlib.h> +#include <stdio.h> +#include <unistd.h> +#include <stdarg.h> +#include <errno.h> +#include <string.h> +#include <assert.h> +#include <inttypes.h> +#include <sys/types.h> +#include <sys/socket.h> +#include <sys/eventfd.h> +#include <sys/mman.h> +#include <endian.h> + +#if defined(__linux__) +#include <sys/syscall.h> +#include <fcntl.h> +#include <sys/ioctl.h> +#include <linux/vhost.h> + +#ifdef __NR_userfaultfd +#include <linux/userfaultfd.h> +#endif + +#endif + +#include "qemu/atomic.h" + +#include "libvhost-user.h" + +/* usually provided by GLib */ +#ifndef MIN +#define MIN(x, y) ({ \ + typeof(x) _min1 = (x); \ + typeof(y) _min2 = (y); \ + (void) (&_min1 == &_min2); \ + _min1 < _min2 ? _min1 : _min2; }) +#endif + +/* Round number down to multiple */ +#define ALIGN_DOWN(n, m) ((n) / (m) * (m)) + +/* Round number up to multiple */ +#define ALIGN_UP(n, m) ALIGN_DOWN((n) + (m) - 1, (m)) + +#ifndef unlikely +#define unlikely(x) __builtin_expect(!!(x), 0) +#endif + +/* Align each region to cache line size in inflight buffer */ +#define INFLIGHT_ALIGNMENT 64 + +/* The version of inflight buffer */ +#define INFLIGHT_VERSION 1 + +/* The version of the protocol we support */ +#define VHOST_USER_VERSION 1 +#define LIBVHOST_USER_DEBUG 0 + +#define DPRINT(...) \ + do { \ + if (LIBVHOST_USER_DEBUG) { \ + fprintf(stderr, __VA_ARGS__); \ + } \ + } while (0) + +static inline +bool has_feature(uint64_t features, unsigned int fbit) +{ + assert(fbit < 64); + return !!(features & (1ULL << fbit)); +} + +static inline +bool vu_has_feature(VuDev *dev, + unsigned int fbit) +{ + return has_feature(dev->features, fbit); +} + +static inline bool vu_has_protocol_feature(VuDev *dev, unsigned int fbit) +{ + return has_feature(dev->protocol_features, fbit); +} + +static const char * +vu_request_to_string(unsigned int req) +{ +#define REQ(req) [req] = #req + static const char *vu_request_str[] = { + REQ(VHOST_USER_NONE), + REQ(VHOST_USER_GET_FEATURES), + REQ(VHOST_USER_SET_FEATURES), + REQ(VHOST_USER_SET_OWNER), + REQ(VHOST_USER_RESET_OWNER), + REQ(VHOST_USER_SET_MEM_TABLE), + REQ(VHOST_USER_SET_LOG_BASE), + REQ(VHOST_USER_SET_LOG_FD), + REQ(VHOST_USER_SET_VRING_NUM), + REQ(VHOST_USER_SET_VRING_ADDR), + REQ(VHOST_USER_SET_VRING_BASE), + REQ(VHOST_USER_GET_VRING_BASE), + REQ(VHOST_USER_SET_VRING_KICK), + REQ(VHOST_USER_SET_VRING_CALL), + REQ(VHOST_USER_SET_VRING_ERR), + REQ(VHOST_USER_GET_PROTOCOL_FEATURES), + REQ(VHOST_USER_SET_PROTOCOL_FEATURES), + REQ(VHOST_USER_GET_QUEUE_NUM), + REQ(VHOST_USER_SET_VRING_ENABLE), + REQ(VHOST_USER_SEND_RARP), + REQ(VHOST_USER_NET_SET_MTU), + REQ(VHOST_USER_SET_SLAVE_REQ_FD), + REQ(VHOST_USER_IOTLB_MSG), + REQ(VHOST_USER_SET_VRING_ENDIAN), + REQ(VHOST_USER_GET_CONFIG), + REQ(VHOST_USER_SET_CONFIG), + REQ(VHOST_USER_POSTCOPY_ADVISE), + REQ(VHOST_USER_POSTCOPY_LISTEN), + REQ(VHOST_USER_POSTCOPY_END), + REQ(VHOST_USER_GET_INFLIGHT_FD), + REQ(VHOST_USER_SET_INFLIGHT_FD), + REQ(VHOST_USER_GPU_SET_SOCKET), + REQ(VHOST_USER_VRING_KICK), + REQ(VHOST_USER_GET_MAX_MEM_SLOTS), + REQ(VHOST_USER_ADD_MEM_REG), + REQ(VHOST_USER_REM_MEM_REG), + REQ(VHOST_USER_MAX), + }; +#undef REQ + + if (req < VHOST_USER_MAX) { + return vu_request_str[req]; + } else { + return "unknown"; + } +} + +static void +vu_panic(VuDev *dev, const char *msg, ...) +{ + char *buf = NULL; + va_list ap; + + va_start(ap, msg); + if (vasprintf(&buf, msg, ap) < 0) { + buf = NULL; + } + va_end(ap); + + dev->broken = true; + dev->panic(dev, buf); + free(buf); + + /* + * FIXME: + * find a way to call virtio_error, or perhaps close the connection? + */ +} + +/* Translate guest physical address to our virtual address. */ +void * +vu_gpa_to_va(VuDev *dev, uint64_t *plen, uint64_t guest_addr) +{ + int i; + + if (*plen == 0) { + return NULL; + } + + /* Find matching memory region. */ + for (i = 0; i < dev->nregions; i++) { + VuDevRegion *r = &dev->regions[i]; + + if ((guest_addr >= r->gpa) && (guest_addr < (r->gpa + r->size))) { + if ((guest_addr + *plen) > (r->gpa + r->size)) { + *plen = r->gpa + r->size - guest_addr; + } + return (void *)(uintptr_t) + guest_addr - r->gpa + r->mmap_addr + r->mmap_offset; + } + } + + return NULL; +} + +/* Translate qemu virtual address to our virtual address. */ +static void * +qva_to_va(VuDev *dev, uint64_t qemu_addr) +{ + int i; + + /* Find matching memory region. */ + for (i = 0; i < dev->nregions; i++) { + VuDevRegion *r = &dev->regions[i]; + + if ((qemu_addr >= r->qva) && (qemu_addr < (r->qva + r->size))) { + return (void *)(uintptr_t) + qemu_addr - r->qva + r->mmap_addr + r->mmap_offset; + } + } + + return NULL; +} + +static void +vmsg_close_fds(VhostUserMsg *vmsg) +{ + int i; + + for (i = 0; i < vmsg->fd_num; i++) { + close(vmsg->fds[i]); + } +} + +/* Set reply payload.u64 and clear request flags and fd_num */ +static void vmsg_set_reply_u64(VhostUserMsg *vmsg, uint64_t val) +{ + vmsg->flags = 0; /* defaults will be set by vu_send_reply() */ + vmsg->size = sizeof(vmsg->payload.u64); + vmsg->payload.u64 = val; + vmsg->fd_num = 0; +} + +/* A test to see if we have userfault available */ +static bool +have_userfault(void) +{ +#if defined(__linux__) && defined(__NR_userfaultfd) &&\ + defined(UFFD_FEATURE_MISSING_SHMEM) &&\ + defined(UFFD_FEATURE_MISSING_HUGETLBFS) + /* Now test the kernel we're running on really has the features */ + int ufd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK); + struct uffdio_api api_struct; + if (ufd < 0) { + return false; + } + + api_struct.api = UFFD_API; + api_struct.features = UFFD_FEATURE_MISSING_SHMEM | + UFFD_FEATURE_MISSING_HUGETLBFS; + if (ioctl(ufd, UFFDIO_API, &api_struct)) { + close(ufd); + return false; + } + close(ufd); + return true; + +#else + return false; +#endif +} + +static bool +vu_message_read_default(VuDev *dev, int conn_fd, VhostUserMsg *vmsg) +{ + char control[CMSG_SPACE(VHOST_MEMORY_BASELINE_NREGIONS * sizeof(int))] = {}; + struct iovec iov = { + .iov_base = (char *)vmsg, + .iov_len = VHOST_USER_HDR_SIZE, + }; + struct msghdr msg = { + .msg_iov = &iov, + .msg_iovlen = 1, + .msg_control = control, + .msg_controllen = sizeof(control), + }; + size_t fd_size; + struct cmsghdr *cmsg; + int rc; + + do { + rc = recvmsg(conn_fd, &msg, 0); + } while (rc < 0 && (errno == EINTR || errno == EAGAIN)); + + if (rc < 0) { + vu_panic(dev, "Error while recvmsg: %s", strerror(errno)); + return false; + } + + vmsg->fd_num = 0; + for (cmsg = CMSG_FIRSTHDR(&msg); + cmsg != NULL; + cmsg = CMSG_NXTHDR(&msg, cmsg)) + { + if (cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SCM_RIGHTS) { + fd_size = cmsg->cmsg_len - CMSG_LEN(0); + vmsg->fd_num = fd_size / sizeof(int); + memcpy(vmsg->fds, CMSG_DATA(cmsg), fd_size); + break; + } + } + + if (vmsg->size > sizeof(vmsg->payload)) { + vu_panic(dev, + "Error: too big message request: %d, size: vmsg->size: %u, " + "while sizeof(vmsg->payload) = %zu\n", + vmsg->request, vmsg->size, sizeof(vmsg->payload)); + goto fail; + } + + if (vmsg->size) { + do { + rc = read(conn_fd, &vmsg->payload, vmsg->size); + } while (rc < 0 && (errno == EINTR || errno == EAGAIN)); + + if (rc <= 0) { + vu_panic(dev, "Error while reading: %s", strerror(errno)); + goto fail; + } + + assert(rc == vmsg->size); + } + + return true; + +fail: + vmsg_close_fds(vmsg); + + return false; +} + +static bool +vu_message_write(VuDev *dev, int conn_fd, VhostUserMsg *vmsg) +{ + int rc; + uint8_t *p = (uint8_t *)vmsg; + char control[CMSG_SPACE(VHOST_MEMORY_BASELINE_NREGIONS * sizeof(int))] = {}; + struct iovec iov = { + .iov_base = (char *)vmsg, + .iov_len = VHOST_USER_HDR_SIZE, + }; + struct msghdr msg = { + .msg_iov = &iov, + .msg_iovlen = 1, + .msg_control = control, + }; + struct cmsghdr *cmsg; + + memset(control, 0, sizeof(control)); + assert(vmsg->fd_num <= VHOST_MEMORY_BASELINE_NREGIONS); + if (vmsg->fd_num > 0) { + size_t fdsize = vmsg->fd_num * sizeof(int); + msg.msg_controllen = CMSG_SPACE(fdsize); + cmsg = CMSG_FIRSTHDR(&msg); + cmsg->cmsg_len = CMSG_LEN(fdsize); + cmsg->cmsg_level = SOL_SOCKET; + cmsg->cmsg_type = SCM_RIGHTS; + memcpy(CMSG_DATA(cmsg), vmsg->fds, fdsize); + } else { + msg.msg_controllen = 0; + } + + do { + rc = sendmsg(conn_fd, &msg, 0); + } while (rc < 0 && (errno == EINTR || errno == EAGAIN)); + + if (vmsg->size) { + do { + if (vmsg->data) { + rc = write(conn_fd, vmsg->data, vmsg->size); + } else { + rc = write(conn_fd, p + VHOST_USER_HDR_SIZE, vmsg->size); + } + } while (rc < 0 && (errno == EINTR || errno == EAGAIN)); + } + + if (rc <= 0) { + vu_panic(dev, "Error while writing: %s", strerror(errno)); + return false; + } + + return true; +} + +static bool +vu_send_reply(VuDev *dev, int conn_fd, VhostUserMsg *vmsg) +{ + /* Set the version in the flags when sending the reply */ + vmsg->flags &= ~VHOST_USER_VERSION_MASK; + vmsg->flags |= VHOST_USER_VERSION; + vmsg->flags |= VHOST_USER_REPLY_MASK; + + return vu_message_write(dev, conn_fd, vmsg); +} + +/* + * Processes a reply on the slave channel. + * Entered with slave_mutex held and releases it before exit. + * Returns true on success. + */ +static bool +vu_process_message_reply(VuDev *dev, const VhostUserMsg *vmsg) +{ + VhostUserMsg msg_reply; + bool result = false; + + if ((vmsg->flags & VHOST_USER_NEED_REPLY_MASK) == 0) { + result = true; + goto out; + } + + if (!vu_message_read_default(dev, dev->slave_fd, &msg_reply)) { + goto out; + } + + if (msg_reply.request != vmsg->request) { + DPRINT("Received unexpected msg type. Expected %d received %d", + vmsg->request, msg_reply.request); + goto out; + } + + result = msg_reply.payload.u64 == 0; + +out: + pthread_mutex_unlock(&dev->slave_mutex); + return result; +} + +/* Kick the log_call_fd if required. */ +static void +vu_log_kick(VuDev *dev) +{ + if (dev->log_call_fd != -1) { + DPRINT("Kicking the QEMU's log...\n"); + if (eventfd_write(dev->log_call_fd, 1) < 0) { + vu_panic(dev, "Error writing eventfd: %s", strerror(errno)); + } + } +} + +static void +vu_log_page(uint8_t *log_table, uint64_t page) +{ + DPRINT("Logged dirty guest page: %"PRId64"\n", page); + qatomic_or(&log_table[page / 8], 1 << (page % 8)); +} + +static void +vu_log_write(VuDev *dev, uint64_t address, uint64_t length) +{ + uint64_t page; + + if (!(dev->features & (1ULL << VHOST_F_LOG_ALL)) || + !dev->log_table || !length) { + return; + } + + assert(dev->log_size > ((address + length - 1) / VHOST_LOG_PAGE / 8)); + + page = address / VHOST_LOG_PAGE; + while (page * VHOST_LOG_PAGE < address + length) { + vu_log_page(dev->log_table, page); + page += 1; + } + + vu_log_kick(dev); +} + +static void +vu_kick_cb(VuDev *dev, int condition, void *data) +{ + int index = (intptr_t)data; + VuVirtq *vq = &dev->vq[index]; + int sock = vq->kick_fd; + eventfd_t kick_data; + ssize_t rc; + + rc = eventfd_read(sock, &kick_data); + if (rc == -1) { + vu_panic(dev, "kick eventfd_read(): %s", strerror(errno)); + dev->remove_watch(dev, dev->vq[index].kick_fd); + } else { + DPRINT("Got kick_data: %016"PRIx64" handler:%p idx:%d\n", + kick_data, vq->handler, index); + if (vq->handler) { + vq->handler(dev, index); + } + } +} + +static bool +vu_get_features_exec(VuDev *dev, VhostUserMsg *vmsg) +{ + vmsg->payload.u64 = + /* + * The following VIRTIO feature bits are supported by our virtqueue + * implementation: + */ + 1ULL << VIRTIO_F_NOTIFY_ON_EMPTY | + 1ULL << VIRTIO_RING_F_INDIRECT_DESC | + 1ULL << VIRTIO_RING_F_EVENT_IDX | + 1ULL << VIRTIO_F_VERSION_1 | + + /* vhost-user feature bits */ + 1ULL << VHOST_F_LOG_ALL | + 1ULL << VHOST_USER_F_PROTOCOL_FEATURES; + + if (dev->iface->get_features) { + vmsg->payload.u64 |= dev->iface->get_features(dev); + } + + vmsg->size = sizeof(vmsg->payload.u64); + vmsg->fd_num = 0; + + DPRINT("Sending back to guest u64: 0x%016"PRIx64"\n", vmsg->payload.u64); + + return true; +} + +static void +vu_set_enable_all_rings(VuDev *dev, bool enabled) +{ + uint16_t i; + + for (i = 0; i < dev->max_queues; i++) { + dev->vq[i].enable = enabled; + } +} + +static bool +vu_set_features_exec(VuDev *dev, VhostUserMsg *vmsg) +{ + DPRINT("u64: 0x%016"PRIx64"\n", vmsg->payload.u64); + + dev->features = vmsg->payload.u64; + if (!vu_has_feature(dev, VIRTIO_F_VERSION_1)) { + /* + * We only support devices conforming to VIRTIO 1.0 or + * later + */ + vu_panic(dev, "virtio legacy devices aren't supported by libvhost-user"); + return false; + } + + if (!(dev->features & VHOST_USER_F_PROTOCOL_FEATURES)) { + vu_set_enable_all_rings(dev, true); + } + + if (dev->iface->set_features) { + dev->iface->set_features(dev, dev->features); + } + + return false; +} + +static bool +vu_set_owner_exec(VuDev *dev, VhostUserMsg *vmsg) +{ + return false; +} + +static void +vu_close_log(VuDev *dev) +{ + if (dev->log_table) { + if (munmap(dev->log_table, dev->log_size) != 0) { + perror("close log munmap() error"); + } + + dev->log_table = NULL; + } + if (dev->log_call_fd != -1) { + close(dev->log_call_fd); + dev->log_call_fd = -1; + } +} + +static bool +vu_reset_device_exec(VuDev *dev, VhostUserMsg *vmsg) +{ + vu_set_enable_all_rings(dev, false); + + return false; +} + +static bool +map_ring(VuDev *dev, VuVirtq *vq) +{ + vq->vring.desc = qva_to_va(dev, vq->vra.desc_user_addr); + vq->vring.used = qva_to_va(dev, vq->vra.used_user_addr); + vq->vring.avail = qva_to_va(dev, vq->vra.avail_user_addr); + + DPRINT("Setting virtq addresses:\n"); + DPRINT(" vring_desc at %p\n", vq->vring.desc); + DPRINT(" vring_used at %p\n", vq->vring.used); + DPRINT(" vring_avail at %p\n", vq->vring.avail); + + return !(vq->vring.desc && vq->vring.used && vq->vring.avail); +} + +static bool +generate_faults(VuDev *dev) { + int i; + for (i = 0; i < dev->nregions; i++) { + VuDevRegion *dev_region = &dev->regions[i]; + int ret; +#ifdef UFFDIO_REGISTER + /* + * We should already have an open ufd. Mark each memory + * range as ufd. + * Discard any mapping we have here; note I can't use MADV_REMOVE + * or fallocate to make the hole since I don't want to lose + * data that's already arrived in the shared process. + * TODO: How to do hugepage + */ + ret = madvise((void *)(uintptr_t)dev_region->mmap_addr, + dev_region->size + dev_region->mmap_offset, + MADV_DONTNEED); + if (ret) { + fprintf(stderr, + "%s: Failed to madvise(DONTNEED) region %d: %s\n", + __func__, i, strerror(errno)); + } + /* + * Turn off transparent hugepages so we dont get lose wakeups + * in neighbouring pages. + * TODO: Turn this backon later. + */ + ret = madvise((void *)(uintptr_t)dev_region->mmap_addr, + dev_region->size + dev_region->mmap_offset, + MADV_NOHUGEPAGE); + if (ret) { + /* + * Note: This can happen legally on kernels that are configured + * without madvise'able hugepages + */ + fprintf(stderr, + "%s: Failed to madvise(NOHUGEPAGE) region %d: %s\n", + __func__, i, strerror(errno)); + } + struct uffdio_register reg_struct; + reg_struct.range.start = (uintptr_t)dev_region->mmap_addr; + reg_struct.range.len = dev_region->size + dev_region->mmap_offset; + reg_struct.mode = UFFDIO_REGISTER_MODE_MISSING; + + if (ioctl(dev->postcopy_ufd, UFFDIO_REGISTER, ®_struct)) { + vu_panic(dev, "%s: Failed to userfault region %d " + "@%p + size:%zx offset: %zx: (ufd=%d)%s\n", + __func__, i, + dev_region->mmap_addr, + dev_region->size, dev_region->mmap_offset, + dev->postcopy_ufd, strerror(errno)); + return false; + } + if (!(reg_struct.ioctls & ((__u64)1 << _UFFDIO_COPY))) { + vu_panic(dev, "%s Region (%d) doesn't support COPY", + __func__, i); + return false; + } + DPRINT("%s: region %d: Registered userfault for %" + PRIx64 " + %" PRIx64 "\n", __func__, i, + (uint64_t)reg_struct.range.start, + (uint64_t)reg_struct.range.len); + /* Now it's registered we can let the client at it */ + if (mprotect((void *)(uintptr_t)dev_region->mmap_addr, + dev_region->size + dev_region->mmap_offset, + PROT_READ | PROT_WRITE)) { + vu_panic(dev, "failed to mprotect region %d for postcopy (%s)", + i, strerror(errno)); + return false; + } + /* TODO: Stash 'zero' support flags somewhere */ +#endif + } + + return true; +} + +static bool +vu_add_mem_reg(VuDev *dev, VhostUserMsg *vmsg) { + int i; + bool track_ramblocks = dev->postcopy_listening; + VhostUserMemoryRegion m = vmsg->payload.memreg.region, *msg_region = &m; + VuDevRegion *dev_region = &dev->regions[dev->nregions]; + void *mmap_addr; + + /* + * If we are in postcopy mode and we receive a u64 payload with a 0 value + * we know all the postcopy client bases have been received, and we + * should start generating faults. + */ + if (track_ramblocks && + vmsg->size == sizeof(vmsg->payload.u64) && + vmsg->payload.u64 == 0) { + (void)generate_faults(dev); + return false; + } + + DPRINT("Adding region: %u\n", dev->nregions); + DPRINT(" guest_phys_addr: 0x%016"PRIx64"\n", + msg_region->guest_phys_addr); + DPRINT(" memory_size: 0x%016"PRIx64"\n", + msg_region->memory_size); + DPRINT(" userspace_addr 0x%016"PRIx64"\n", + msg_region->userspace_addr); + DPRINT(" mmap_offset 0x%016"PRIx64"\n", + msg_region->mmap_offset); + + dev_region->gpa = msg_region->guest_phys_addr; + dev_region->size = msg_region->memory_size; + dev_region->qva = msg_region->userspace_addr; + dev_region->mmap_offset = msg_region->mmap_offset; + + /* + * We don't use offset argument of mmap() since the + * mapped address has to be page aligned, and we use huge + * pages. + */ + if (track_ramblocks) { + /* + * In postcopy we're using PROT_NONE here to catch anyone + * accessing it before we userfault. + */ + mmap_addr = mmap(0, dev_region->size + dev_region->mmap_offset, + PROT_NONE, MAP_SHARED, + vmsg->fds[0], 0); + } else { + mmap_addr = mmap(0, dev_region->size + dev_region->mmap_offset, + PROT_READ | PROT_WRITE, MAP_SHARED, vmsg->fds[0], + 0); + } + + if (mmap_addr == MAP_FAILED) { + vu_panic(dev, "region mmap error: %s", strerror(errno)); + } else { + dev_region->mmap_addr = (uint64_t)(uintptr_t)mmap_addr; + DPRINT(" mmap_addr: 0x%016"PRIx64"\n", + dev_region->mmap_addr); + } + + close(vmsg->fds[0]); + + if (track_ramblocks) { + /* + * Return the address to QEMU so that it can translate the ufd + * fault addresses back. + */ + msg_region->userspace_addr = (uintptr_t)(mmap_addr + + dev_region->mmap_offset); + + /* Send the message back to qemu with the addresses filled in. */ + vmsg->fd_num = 0; + if (!vu_send_reply(dev, dev->sock, vmsg)) { + vu_panic(dev, "failed to respond to add-mem-region for postcopy"); + return false; + } + + DPRINT("Successfully added new region in postcopy\n"); + dev->nregions++; + return false; + + } else { + for (i = 0; i < dev->max_queues; i++) { + if (dev->vq[i].vring.desc) { + if (map_ring(dev, &dev->vq[i])) { + vu_panic(dev, "remapping queue %d for new memory region", + i); + } + } + } + + DPRINT("Successfully added new region\n"); + dev->nregions++; + vmsg_set_reply_u64(vmsg, 0); + return true; + } +} + +static inline bool reg_equal(VuDevRegion *vudev_reg, + VhostUserMemoryRegion *msg_reg) +{ + if (vudev_reg->gpa == msg_reg->guest_phys_addr && + vudev_reg->qva == msg_reg->userspace_addr && + vudev_reg->size == msg_reg->memory_size) { + return true; + } + + return false; +} + +static bool +vu_rem_mem_reg(VuDev *dev, VhostUserMsg *vmsg) { + int i, j; + bool found = false; + VuDevRegion shadow_regions[VHOST_USER_MAX_RAM_SLOTS] = {}; + VhostUserMemoryRegion m = vmsg->payload.memreg.region, *msg_region = &m; + + DPRINT("Removing region:\n"); + DPRINT(" guest_phys_addr: 0x%016"PRIx64"\n", + msg_region->guest_phys_addr); + DPRINT(" memory_size: 0x%016"PRIx64"\n", + msg_region->memory_size); + DPRINT(" userspace_addr 0x%016"PRIx64"\n", + msg_region->userspace_addr); + DPRINT(" mmap_offset 0x%016"PRIx64"\n", + msg_region->mmap_offset); + + for (i = 0, j = 0; i < dev->nregions; i++) { + if (!reg_equal(&dev->regions[i], msg_region)) { + shadow_regions[j].gpa = dev->regions[i].gpa; + shadow_regions[j].size = dev->regions[i].size; + shadow_regions[j].qva = dev->regions[i].qva; + shadow_regions[j].mmap_offset = dev->regions[i].mmap_offset; + j++; + } else { + found = true; + VuDevRegion *r = &dev->regions[i]; + void *m = (void *) (uintptr_t) r->mmap_addr; + + if (m) { + munmap(m, r->size + r->mmap_offset); + } + } + } + + if (found) { + memcpy(dev->regions, shadow_regions, + sizeof(VuDevRegion) * VHOST_USER_MAX_RAM_SLOTS); + DPRINT("Successfully removed a region\n"); + dev->nregions--; + vmsg_set_reply_u64(vmsg, 0); + } else { + vu_panic(dev, "Specified region not found\n"); + } + + return true; +} + +static bool +vu_set_mem_table_exec_postcopy(VuDev *dev, VhostUserMsg *vmsg) +{ + int i; + VhostUserMemory m = vmsg->payload.memory, *memory = &m; + dev->nregions = memory->nregions; + + DPRINT("Nregions: %u\n", memory->nregions); + for (i = 0; i < dev->nregions; i++) { + void *mmap_addr; + VhostUserMemoryRegion *msg_region = &memory->regions[i]; + VuDevRegion *dev_region = &dev->regions[i]; + + DPRINT("Region %d\n", i); + DPRINT(" guest_phys_addr: 0x%016"PRIx64"\n", + msg_region->guest_phys_addr); + DPRINT(" memory_size: 0x%016"PRIx64"\n", + msg_region->memory_size); + DPRINT(" userspace_addr 0x%016"PRIx64"\n", + msg_region->userspace_addr); + DPRINT(" mmap_offset 0x%016"PRIx64"\n", + msg_region->mmap_offset); + + dev_region->gpa = msg_region->guest_phys_addr; + dev_region->size = msg_region->memory_size; + dev_region->qva = msg_region->userspace_addr; + dev_region->mmap_offset = msg_region->mmap_offset; + + /* We don't use offset argument of mmap() since the + * mapped address has to be page aligned, and we use huge + * pages. + * In postcopy we're using PROT_NONE here to catch anyone + * accessing it before we userfault + */ + mmap_addr = mmap(0, dev_region->size + dev_region->mmap_offset, + PROT_NONE, MAP_SHARED, + vmsg->fds[i], 0); + + if (mmap_addr == MAP_FAILED) { + vu_panic(dev, "region mmap error: %s", strerror(errno)); + } else { + dev_region->mmap_addr = (uint64_t)(uintptr_t)mmap_addr; + DPRINT(" mmap_addr: 0x%016"PRIx64"\n", + dev_region->mmap_addr); + } + + /* Return the address to QEMU so that it can translate the ufd + * fault addresses back. + */ + msg_region->userspace_addr = (uintptr_t)(mmap_addr + + dev_region->mmap_offset); + close(vmsg->fds[i]); + } + + /* Send the message back to qemu with the addresses filled in */ + vmsg->fd_num = 0; + if (!vu_send_reply(dev, dev->sock, vmsg)) { + vu_panic(dev, "failed to respond to set-mem-table for postcopy"); + return false; + } + + /* Wait for QEMU to confirm that it's registered the handler for the + * faults. + */ + if (!dev->read_msg(dev, dev->sock, vmsg) || + vmsg->size != sizeof(vmsg->payload.u64) || + vmsg->payload.u64 != 0) { + vu_panic(dev, "failed to receive valid ack for postcopy set-mem-table"); + return false; + } + + /* OK, now we can go and register the memory and generate faults */ + (void)generate_faults(dev); + + return false; +} + +static bool +vu_set_mem_table_exec(VuDev *dev, VhostUserMsg *vmsg) +{ + int i; + VhostUserMemory m = vmsg->payload.memory, *memory = &m; + + for (i = 0; i < dev->nregions; i++) { + VuDevRegion *r = &dev->regions[i]; + void *m = (void *) (uintptr_t) r->mmap_addr; + + if (m) { + munmap(m, r->size + r->mmap_offset); + } + } + dev->nregions = memory->nregions; + + if (dev->postcopy_listening) { + return vu_set_mem_table_exec_postcopy(dev, vmsg); + } + + DPRINT("Nregions: %u\n", memory->nregions); + for (i = 0; i < dev->nregions; i++) { + void *mmap_addr; + VhostUserMemoryRegion *msg_region = &memory->regions[i]; + VuDevRegion *dev_region = &dev->regions[i]; + + DPRINT("Region %d\n", i); + DPRINT(" guest_phys_addr: 0x%016"PRIx64"\n", + msg_region->guest_phys_addr); + DPRINT(" memory_size: 0x%016"PRIx64"\n", + msg_region->memory_size); + DPRINT(" userspace_addr 0x%016"PRIx64"\n", + msg_region->userspace_addr); + DPRINT(" mmap_offset 0x%016"PRIx64"\n", + msg_region->mmap_offset); + + dev_region->gpa = msg_region->guest_phys_addr; + dev_region->size = msg_region->memory_size; + dev_region->qva = msg_region->userspace_addr; + dev_region->mmap_offset = msg_region->mmap_offset; + + /* We don't use offset argument of mmap() since the + * mapped address has to be page aligned, and we use huge + * pages. */ + mmap_addr = mmap(0, dev_region->size + dev_region->mmap_offset, + PROT_READ | PROT_WRITE, MAP_SHARED, + vmsg->fds[i], 0); + + if (mmap_addr == MAP_FAILED) { + vu_panic(dev, "region mmap error: %s", strerror(errno)); + } else { + dev_region->mmap_addr = (uint64_t)(uintptr_t)mmap_addr; + DPRINT(" mmap_addr: 0x%016"PRIx64"\n", + dev_region->mmap_addr); + } + + close(vmsg->fds[i]); + } + + for (i = 0; i < dev->max_queues; i++) { + if (dev->vq[i].vring.desc) { + if (map_ring(dev, &dev->vq[i])) { + vu_panic(dev, "remapping queue %d during setmemtable", i); + } + } + } + + return false; +} + +static bool +vu_set_log_base_exec(VuDev *dev, VhostUserMsg *vmsg) +{ + int fd; + uint64_t log_mmap_size, log_mmap_offset; + void *rc; + + if (vmsg->fd_num != 1 || + vmsg->size != sizeof(vmsg->payload.log)) { + vu_panic(dev, "Invalid log_base message"); + return true; + } + + fd = vmsg->fds[0]; + log_mmap_offset = vmsg->payload.log.mmap_offset; + log_mmap_size = vmsg->payload.log.mmap_size; + DPRINT("Log mmap_offset: %"PRId64"\n", log_mmap_offset); + DPRINT("Log mmap_size: %"PRId64"\n", log_mmap_size); + + rc = mmap(0, log_mmap_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, + log_mmap_offset); + close(fd); + if (rc == MAP_FAILED) { + perror("log mmap error"); + } + + if (dev->log_table) { + munmap(dev->log_table, dev->log_size); + } + dev->log_table = rc; + dev->log_size = log_mmap_size; + + vmsg->size = sizeof(vmsg->payload.u64); + vmsg->fd_num = 0; + + return true; +} + +static bool +vu_set_log_fd_exec(VuDev *dev, VhostUserMsg *vmsg) +{ + if (vmsg->fd_num != 1) { + vu_panic(dev, "Invalid log_fd message"); + return false; + } + + if (dev->log_call_fd != -1) { + close(dev->log_call_fd); + } + dev->log_call_fd = vmsg->fds[0]; + DPRINT("Got log_call_fd: %d\n", vmsg->fds[0]); + + return false; +} + +static bool +vu_set_vring_num_exec(VuDev *dev, VhostUserMsg *vmsg) +{ + unsigned int index = vmsg->payload.state.index; + unsigned int num = vmsg->payload.state.num; + + DPRINT("State.index: %u\n", index); + DPRINT("State.num: %u\n", num); + dev->vq[index].vring.num = num; + + return false; +} + +static bool +vu_set_vring_addr_exec(VuDev *dev, VhostUserMsg *vmsg) +{ + struct vhost_vring_addr addr = vmsg->payload.addr, *vra = &addr; + unsigned int index = vra->index; + VuVirtq *vq = &dev->vq[index]; + + DPRINT("vhost_vring_addr:\n"); + DPRINT(" index: %d\n", vra->index); + DPRINT(" flags: %d\n", vra->flags); + DPRINT(" desc_user_addr: 0x%016" PRIx64 "\n", vra->desc_user_addr); + DPRINT(" used_user_addr: 0x%016" PRIx64 "\n", vra->used_user_addr); + DPRINT(" avail_user_addr: 0x%016" PRIx64 "\n", vra->avail_user_addr); + DPRINT(" log_guest_addr: 0x%016" PRIx64 "\n", vra->log_guest_addr); + + vq->vra = *vra; + vq->vring.flags = vra->flags; + vq->vring.log_guest_addr = vra->log_guest_addr; + + + if (map_ring(dev, vq)) { + vu_panic(dev, "Invalid vring_addr message"); + return false; + } + + vq->used_idx = le16toh(vq->vring.used->idx); + + if (vq->last_avail_idx != vq->used_idx) { + bool resume = dev->iface->queue_is_processed_in_order && + dev->iface->queue_is_processed_in_order(dev, index); + + DPRINT("Last avail index != used index: %u != %u%s\n", + vq->last_avail_idx, vq->used_idx, + resume ? ", resuming" : ""); + + if (resume) { + vq->shadow_avail_idx = vq->last_avail_idx = vq->used_idx; + } + } + + return false; +} + +static bool +vu_set_vring_base_exec(VuDev *dev, VhostUserMsg *vmsg) +{ + unsigned int index = vmsg->payload.state.index; + unsigned int num = vmsg->payload.state.num; + + DPRINT("State.index: %u\n", index); + DPRINT("State.num: %u\n", num); + dev->vq[index].shadow_avail_idx = dev->vq[index].last_avail_idx = num; + + return false; +} + +static bool +vu_get_vring_base_exec(VuDev *dev, VhostUserMsg *vmsg) +{ + unsigned int index = vmsg->payload.state.index; + + DPRINT("State.index: %u\n", index); + vmsg->payload.state.num = dev->vq[index].last_avail_idx; + vmsg->size = sizeof(vmsg->payload.state); + + dev->vq[index].started = false; + if (dev->iface->queue_set_started) { + dev->iface->queue_set_started(dev, index, false); + } + + if (dev->vq[index].call_fd != -1) { + close(dev->vq[index].call_fd); + dev->vq[index].call_fd = -1; + } + if (dev->vq[index].kick_fd != -1) { + dev->remove_watch(dev, dev->vq[index].kick_fd); + close(dev->vq[index].kick_fd); + dev->vq[index].kick_fd = -1; + } + + return true; +} + +static bool +vu_check_queue_msg_file(VuDev *dev, VhostUserMsg *vmsg) +{ + int index = vmsg->payload.u64 & VHOST_USER_VRING_IDX_MASK; + bool nofd = vmsg->payload.u64 & VHOST_USER_VRING_NOFD_MASK; + + if (index >= dev->max_queues) { + vmsg_close_fds(vmsg); + vu_panic(dev, "Invalid queue index: %u", index); + return false; + } + + if (nofd) { + vmsg_close_fds(vmsg); + return true; + } + + if (vmsg->fd_num != 1) { + vmsg_close_fds(vmsg); + vu_panic(dev, "Invalid fds in request: %d", vmsg->request); + return false; + } + + return true; +} + +static int +inflight_desc_compare(const void *a, const void *b) +{ + VuVirtqInflightDesc *desc0 = (VuVirtqInflightDesc *)a, + *desc1 = (VuVirtqInflightDesc *)b; + + if (desc1->counter > desc0->counter && + (desc1->counter - desc0->counter) < VIRTQUEUE_MAX_SIZE * 2) { + return 1; + } + + return -1; +} + +static int +vu_check_queue_inflights(VuDev *dev, VuVirtq *vq) +{ + int i = 0; + + if (!vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD)) { + return 0; + } + + if (unlikely(!vq->inflight)) { + return -1; + } + + if (unlikely(!vq->inflight->version)) { + /* initialize the buffer */ + vq->inflight->version = INFLIGHT_VERSION; + return 0; + } + + vq->used_idx = le16toh(vq->vring.used->idx); + vq->resubmit_num = 0; + vq->resubmit_list = NULL; + vq->counter = 0; + + if (unlikely(vq->inflight->used_idx != vq->used_idx)) { + vq->inflight->desc[vq->inflight->last_batch_head].inflight = 0; + + barrier(); + + vq->inflight->used_idx = vq->used_idx; + } + + for (i = 0; i < vq->inflight->desc_num; i++) { + if (vq->inflight->desc[i].inflight == 1) { + vq->inuse++; + } + } + + vq->shadow_avail_idx = vq->last_avail_idx = vq->inuse + vq->used_idx; + + if (vq->inuse) { + vq->resubmit_list = calloc(vq->inuse, sizeof(VuVirtqInflightDesc)); + if (!vq->resubmit_list) { + return -1; + } + + for (i = 0; i < vq->inflight->desc_num; i++) { + if (vq->inflight->desc[i].inflight) { + vq->resubmit_list[vq->resubmit_num].index = i; + vq->resubmit_list[vq->resubmit_num].counter = + vq->inflight->desc[i].counter; + vq->resubmit_num++; + } + } + + if (vq->resubmit_num > 1) { + qsort(vq->resubmit_list, vq->resubmit_num, + sizeof(VuVirtqInflightDesc), inflight_desc_compare); + } + vq->counter = vq->resubmit_list[0].counter + 1; + } + + /* in case of I/O hang after reconnecting */ + if (eventfd_write(vq->kick_fd, 1)) { + return -1; + } + + return 0; +} + +static bool +vu_set_vring_kick_exec(VuDev *dev, VhostUserMsg *vmsg) +{ + int index = vmsg->payload.u64 & VHOST_USER_VRING_IDX_MASK; + bool nofd = vmsg->payload.u64 & VHOST_USER_VRING_NOFD_MASK; + + DPRINT("u64: 0x%016"PRIx64"\n", vmsg->payload.u64); + + if (!vu_check_queue_msg_file(dev, vmsg)) { + return false; + } + + if (dev->vq[index].kick_fd != -1) { + dev->remove_watch(dev, dev->vq[index].kick_fd); + close(dev->vq[index].kick_fd); + dev->vq[index].kick_fd = -1; + } + + dev->vq[index].kick_fd = nofd ? -1 : vmsg->fds[0]; + DPRINT("Got kick_fd: %d for vq: %d\n", dev->vq[index].kick_fd, index); + + dev->vq[index].started = true; + if (dev->iface->queue_set_started) { + dev->iface->queue_set_started(dev, index, true); + } + + if (dev->vq[index].kick_fd != -1 && dev->vq[index].handler) { + dev->set_watch(dev, dev->vq[index].kick_fd, VU_WATCH_IN, + vu_kick_cb, (void *)(long)index); + + DPRINT("Waiting for kicks on fd: %d for vq: %d\n", + dev->vq[index].kick_fd, index); + } + + if (vu_check_queue_inflights(dev, &dev->vq[index])) { + vu_panic(dev, "Failed to check inflights for vq: %d\n", index); + } + + return false; +} + +void vu_set_queue_handler(VuDev *dev, VuVirtq *vq, + vu_queue_handler_cb handler) +{ + int qidx = vq - dev->vq; + + vq->handler = handler; + if (vq->kick_fd >= 0) { + if (handler) { + dev->set_watch(dev, vq->kick_fd, VU_WATCH_IN, + vu_kick_cb, (void *)(long)qidx); + } else { + dev->remove_watch(dev, vq->kick_fd); + } + } +} + +bool vu_set_queue_host_notifier(VuDev *dev, VuVirtq *vq, int fd, + int size, int offset) +{ + int qidx = vq - dev->vq; + int fd_num = 0; + VhostUserMsg vmsg = { + .request = VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG, + .flags = VHOST_USER_VERSION | VHOST_USER_NEED_REPLY_MASK, + .size = sizeof(vmsg.payload.area), + .payload.area = { + .u64 = qidx & VHOST_USER_VRING_IDX_MASK, + .size = size, + .offset = offset, + }, + }; + + if (fd == -1) { + vmsg.payload.area.u64 |= VHOST_USER_VRING_NOFD_MASK; + } else { + vmsg.fds[fd_num++] = fd; + } + + vmsg.fd_num = fd_num; + + if (!vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD)) { + return false; + } + + pthread_mutex_lock(&dev->slave_mutex); + if (!vu_message_write(dev, dev->slave_fd, &vmsg)) { + pthread_mutex_unlock(&dev->slave_mutex); + return false; + } + + /* Also unlocks the slave_mutex */ + return vu_process_message_reply(dev, &vmsg); +} + +static bool +vu_set_vring_call_exec(VuDev *dev, VhostUserMsg *vmsg) +{ + int index = vmsg->payload.u64 & VHOST_USER_VRING_IDX_MASK; + bool nofd = vmsg->payload.u64 & VHOST_USER_VRING_NOFD_MASK; + + DPRINT("u64: 0x%016"PRIx64"\n", vmsg->payload.u64); + + if (!vu_check_queue_msg_file(dev, vmsg)) { + return false; + } + + if (dev->vq[index].call_fd != -1) { + close(dev->vq[index].call_fd); + dev->vq[index].call_fd = -1; + } + + dev->vq[index].call_fd = nofd ? -1 : vmsg->fds[0]; + + /* in case of I/O hang after reconnecting */ + if (dev->vq[index].call_fd != -1 && eventfd_write(vmsg->fds[0], 1)) { + return -1; + } + + DPRINT("Got call_fd: %d for vq: %d\n", dev->vq[index].call_fd, index); + + return false; +} + +static bool +vu_set_vring_err_exec(VuDev *dev, VhostUserMsg *vmsg) +{ + int index = vmsg->payload.u64 & VHOST_USER_VRING_IDX_MASK; + bool nofd = vmsg->payload.u64 & VHOST_USER_VRING_NOFD_MASK; + + DPRINT("u64: 0x%016"PRIx64"\n", vmsg->payload.u64); + + if (!vu_check_queue_msg_file(dev, vmsg)) { + return false; + } + + if (dev->vq[index].err_fd != -1) { + close(dev->vq[index].err_fd); + dev->vq[index].err_fd = -1; + } + + dev->vq[index].err_fd = nofd ? -1 : vmsg->fds[0]; + + return false; +} + +static bool +vu_get_protocol_features_exec(VuDev *dev, VhostUserMsg *vmsg) +{ + /* + * Note that we support, but intentionally do not set, + * VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS. This means that + * a device implementation can return it in its callback + * (get_protocol_features) if it wants to use this for + * simulation, but it is otherwise not desirable (if even + * implemented by the master.) + */ + uint64_t features = 1ULL << VHOST_USER_PROTOCOL_F_MQ | + 1ULL << VHOST_USER_PROTOCOL_F_LOG_SHMFD | + 1ULL << VHOST_USER_PROTOCOL_F_SLAVE_REQ | + 1ULL << VHOST_USER_PROTOCOL_F_HOST_NOTIFIER | + 1ULL << VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD | + 1ULL << VHOST_USER_PROTOCOL_F_REPLY_ACK | + 1ULL << VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS; + + if (have_userfault()) { + features |= 1ULL << VHOST_USER_PROTOCOL_F_PAGEFAULT; + } + + if (dev->iface->get_config && dev->iface->set_config) { + features |= 1ULL << VHOST_USER_PROTOCOL_F_CONFIG; + } + + if (dev->iface->get_protocol_features) { + features |= dev->iface->get_protocol_features(dev); + } + + vmsg_set_reply_u64(vmsg, features); + return true; +} + +static bool +vu_set_protocol_features_exec(VuDev *dev, VhostUserMsg *vmsg) +{ + uint64_t features = vmsg->payload.u64; + + DPRINT("u64: 0x%016"PRIx64"\n", features); + + dev->protocol_features = vmsg->payload.u64; + + if (vu_has_protocol_feature(dev, + VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS) && + (!vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_SLAVE_REQ) || + !vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_REPLY_ACK))) { + /* + * The use case for using messages for kick/call is simulation, to make + * the kick and call synchronous. To actually get that behaviour, both + * of the other features are required. + * Theoretically, one could use only kick messages, or do them without + * having F_REPLY_ACK, but too many (possibly pending) messages on the + * socket will eventually cause the master to hang, to avoid this in + * scenarios where not desired enforce that the settings are in a way + * that actually enables the simulation case. + */ + vu_panic(dev, + "F_IN_BAND_NOTIFICATIONS requires F_SLAVE_REQ && F_REPLY_ACK"); + return false; + } + + if (dev->iface->set_protocol_features) { + dev->iface->set_protocol_features(dev, features); + } + + return false; +} + +static bool +vu_get_queue_num_exec(VuDev *dev, VhostUserMsg *vmsg) +{ + vmsg_set_reply_u64(vmsg, dev->max_queues); + return true; +} + +static bool +vu_set_vring_enable_exec(VuDev *dev, VhostUserMsg *vmsg) +{ + unsigned int index = vmsg->payload.state.index; + unsigned int enable = vmsg->payload.state.num; + + DPRINT("State.index: %u\n", index); + DPRINT("State.enable: %u\n", enable); + + if (index >= dev->max_queues) { + vu_panic(dev, "Invalid vring_enable index: %u", index); + return false; + } + + dev->vq[index].enable = enable; + return false; +} + +static bool +vu_set_slave_req_fd(VuDev *dev, VhostUserMsg *vmsg) +{ + if (vmsg->fd_num != 1) { + vu_panic(dev, "Invalid slave_req_fd message (%d fd's)", vmsg->fd_num); + return false; + } + + if (dev->slave_fd != -1) { + close(dev->slave_fd); + } + dev->slave_fd = vmsg->fds[0]; + DPRINT("Got slave_fd: %d\n", vmsg->fds[0]); + + return false; +} + +static bool +vu_get_config(VuDev *dev, VhostUserMsg *vmsg) +{ + int ret = -1; + + if (dev->iface->get_config) { + ret = dev->iface->get_config(dev, vmsg->payload.config.region, + vmsg->payload.config.size); + } + + if (ret) { + /* resize to zero to indicate an error to master */ + vmsg->size = 0; + } + + return true; +} + +static bool +vu_set_config(VuDev *dev, VhostUserMsg *vmsg) +{ + int ret = -1; + + if (dev->iface->set_config) { + ret = dev->iface->set_config(dev, vmsg->payload.config.region, + vmsg->payload.config.offset, + vmsg->payload.config.size, + vmsg->payload.config.flags); + if (ret) { + vu_panic(dev, "Set virtio configuration space failed"); + } + } + + return false; +} + +static bool +vu_set_postcopy_advise(VuDev *dev, VhostUserMsg *vmsg) +{ + dev->postcopy_ufd = -1; +#ifdef UFFDIO_API + struct uffdio_api api_struct; + + dev->postcopy_ufd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK); + vmsg->size = 0; +#endif + + if (dev->postcopy_ufd == -1) { + vu_panic(dev, "Userfaultfd not available: %s", strerror(errno)); + goto out; + } + +#ifdef UFFDIO_API + api_struct.api = UFFD_API; + api_struct.features = 0; + if (ioctl(dev->postcopy_ufd, UFFDIO_API, &api_struct)) { + vu_panic(dev, "Failed UFFDIO_API: %s", strerror(errno)); + close(dev->postcopy_ufd); + dev->postcopy_ufd = -1; + goto out; + } + /* TODO: Stash feature flags somewhere */ +#endif + +out: + /* Return a ufd to the QEMU */ + vmsg->fd_num = 1; + vmsg->fds[0] = dev->postcopy_ufd; + return true; /* = send a reply */ +} + +static bool +vu_set_postcopy_listen(VuDev *dev, VhostUserMsg *vmsg) +{ + if (dev->nregions) { + vu_panic(dev, "Regions already registered at postcopy-listen"); + vmsg_set_reply_u64(vmsg, -1); + return true; + } + dev->postcopy_listening = true; + + vmsg_set_reply_u64(vmsg, 0); + return true; +} + +static bool +vu_set_postcopy_end(VuDev *dev, VhostUserMsg *vmsg) +{ + DPRINT("%s: Entry\n", __func__); + dev->postcopy_listening = false; + if (dev->postcopy_ufd > 0) { + close(dev->postcopy_ufd); + dev->postcopy_ufd = -1; + DPRINT("%s: Done close\n", __func__); + } + + vmsg_set_reply_u64(vmsg, 0); + DPRINT("%s: exit\n", __func__); + return true; +} + +static inline uint64_t +vu_inflight_queue_size(uint16_t queue_size) +{ + return ALIGN_UP(sizeof(VuDescStateSplit) * queue_size + + sizeof(uint16_t), INFLIGHT_ALIGNMENT); +} + +#ifdef MFD_ALLOW_SEALING +static void * +memfd_alloc(const char *name, size_t size, unsigned int flags, int *fd) +{ + void *ptr; + int ret; + + *fd = memfd_create(name, MFD_ALLOW_SEALING); + if (*fd < 0) { + return NULL; + } + + ret = ftruncate(*fd, size); + if (ret < 0) { + close(*fd); + return NULL; + } + + ret = fcntl(*fd, F_ADD_SEALS, flags); + if (ret < 0) { + close(*fd); + return NULL; + } + + ptr = mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, *fd, 0); + if (ptr == MAP_FAILED) { + close(*fd); + return NULL; + } + + return ptr; +} +#endif + +static bool +vu_get_inflight_fd(VuDev *dev, VhostUserMsg *vmsg) +{ + int fd = -1; + void *addr = NULL; + uint64_t mmap_size; + uint16_t num_queues, queue_size; + + if (vmsg->size != sizeof(vmsg->payload.inflight)) { + vu_panic(dev, "Invalid get_inflight_fd message:%d", vmsg->size); + vmsg->payload.inflight.mmap_size = 0; + return true; + } + + num_queues = vmsg->payload.inflight.num_queues; + queue_size = vmsg->payload.inflight.queue_size; + + DPRINT("set_inflight_fd num_queues: %"PRId16"\n", num_queues); + DPRINT("set_inflight_fd queue_size: %"PRId16"\n", queue_size); + + mmap_size = vu_inflight_queue_size(queue_size) * num_queues; + +#ifdef MFD_ALLOW_SEALING + addr = memfd_alloc("vhost-inflight", mmap_size, + F_SEAL_GROW | F_SEAL_SHRINK | F_SEAL_SEAL, + &fd); +#else + vu_panic(dev, "Not implemented: memfd support is missing"); +#endif + + if (!addr) { + vu_panic(dev, "Failed to alloc vhost inflight area"); + vmsg->payload.inflight.mmap_size = 0; + return true; + } + + memset(addr, 0, mmap_size); + + dev->inflight_info.addr = addr; + dev->inflight_info.size = vmsg->payload.inflight.mmap_size = mmap_size; + dev->inflight_info.fd = vmsg->fds[0] = fd; + vmsg->fd_num = 1; + vmsg->payload.inflight.mmap_offset = 0; + + DPRINT("send inflight mmap_size: %"PRId64"\n", + vmsg->payload.inflight.mmap_size); + DPRINT("send inflight mmap offset: %"PRId64"\n", + vmsg->payload.inflight.mmap_offset); + + return true; +} + +static bool +vu_set_inflight_fd(VuDev *dev, VhostUserMsg *vmsg) +{ + int fd, i; + uint64_t mmap_size, mmap_offset; + uint16_t num_queues, queue_size; + void *rc; + + if (vmsg->fd_num != 1 || + vmsg->size != sizeof(vmsg->payload.inflight)) { + vu_panic(dev, "Invalid set_inflight_fd message size:%d fds:%d", + vmsg->size, vmsg->fd_num); + return false; + } + + fd = vmsg->fds[0]; + mmap_size = vmsg->payload.inflight.mmap_size; + mmap_offset = vmsg->payload.inflight.mmap_offset; + num_queues = vmsg->payload.inflight.num_queues; + queue_size = vmsg->payload.inflight.queue_size; + + DPRINT("set_inflight_fd mmap_size: %"PRId64"\n", mmap_size); + DPRINT("set_inflight_fd mmap_offset: %"PRId64"\n", mmap_offset); + DPRINT("set_inflight_fd num_queues: %"PRId16"\n", num_queues); + DPRINT("set_inflight_fd queue_size: %"PRId16"\n", queue_size); + + rc = mmap(0, mmap_size, PROT_READ | PROT_WRITE, MAP_SHARED, + fd, mmap_offset); + + if (rc == MAP_FAILED) { + vu_panic(dev, "set_inflight_fd mmap error: %s", strerror(errno)); + return false; + } + + if (dev->inflight_info.fd) { + close(dev->inflight_info.fd); + } + + if (dev->inflight_info.addr) { + munmap(dev->inflight_info.addr, dev->inflight_info.size); + } + + dev->inflight_info.fd = fd; + dev->inflight_info.addr = rc; + dev->inflight_info.size = mmap_size; + + for (i = 0; i < num_queues; i++) { + dev->vq[i].inflight = (VuVirtqInflight *)rc; + dev->vq[i].inflight->desc_num = queue_size; + rc = (void *)((char *)rc + vu_inflight_queue_size(queue_size)); + } + + return false; +} + +static bool +vu_handle_vring_kick(VuDev *dev, VhostUserMsg *vmsg) +{ + unsigned int index = vmsg->payload.state.index; + + if (index >= dev->max_queues) { + vu_panic(dev, "Invalid queue index: %u", index); + return false; + } + + DPRINT("Got kick message: handler:%p idx:%u\n", + dev->vq[index].handler, index); + + if (!dev->vq[index].started) { + dev->vq[index].started = true; + + if (dev->iface->queue_set_started) { + dev->iface->queue_set_started(dev, index, true); + } + } + + if (dev->vq[index].handler) { + dev->vq[index].handler(dev, index); + } + + return false; +} + +static bool vu_handle_get_max_memslots(VuDev *dev, VhostUserMsg *vmsg) +{ + vmsg->flags = VHOST_USER_REPLY_MASK | VHOST_USER_VERSION; + vmsg->size = sizeof(vmsg->payload.u64); + vmsg->payload.u64 = VHOST_USER_MAX_RAM_SLOTS; + vmsg->fd_num = 0; + + if (!vu_message_write(dev, dev->sock, vmsg)) { + vu_panic(dev, "Failed to send max ram slots: %s\n", strerror(errno)); + } + + DPRINT("u64: 0x%016"PRIx64"\n", (uint64_t) VHOST_USER_MAX_RAM_SLOTS); + + return false; +} + +static bool +vu_process_message(VuDev *dev, VhostUserMsg *vmsg) +{ + int do_reply = 0; + + /* Print out generic part of the request. */ + DPRINT("================ Vhost user message ================\n"); + DPRINT("Request: %s (%d)\n", vu_request_to_string(vmsg->request), + vmsg->request); + DPRINT("Flags: 0x%x\n", vmsg->flags); + DPRINT("Size: %u\n", vmsg->size); + + if (vmsg->fd_num) { + int i; + DPRINT("Fds:"); + for (i = 0; i < vmsg->fd_num; i++) { + DPRINT(" %d", vmsg->fds[i]); + } + DPRINT("\n"); + } + + if (dev->iface->process_msg && + dev->iface->process_msg(dev, vmsg, &do_reply)) { + return do_reply; + } + + switch (vmsg->request) { + case VHOST_USER_GET_FEATURES: + return vu_get_features_exec(dev, vmsg); + case VHOST_USER_SET_FEATURES: + return vu_set_features_exec(dev, vmsg); + case VHOST_USER_GET_PROTOCOL_FEATURES: + return vu_get_protocol_features_exec(dev, vmsg); + case VHOST_USER_SET_PROTOCOL_FEATURES: + return vu_set_protocol_features_exec(dev, vmsg); + case VHOST_USER_SET_OWNER: + return vu_set_owner_exec(dev, vmsg); + case VHOST_USER_RESET_OWNER: + return vu_reset_device_exec(dev, vmsg); + case VHOST_USER_SET_MEM_TABLE: + return vu_set_mem_table_exec(dev, vmsg); + case VHOST_USER_SET_LOG_BASE: + return vu_set_log_base_exec(dev, vmsg); + case VHOST_USER_SET_LOG_FD: + return vu_set_log_fd_exec(dev, vmsg); + case VHOST_USER_SET_VRING_NUM: + return vu_set_vring_num_exec(dev, vmsg); + case VHOST_USER_SET_VRING_ADDR: + return vu_set_vring_addr_exec(dev, vmsg); + case VHOST_USER_SET_VRING_BASE: + return vu_set_vring_base_exec(dev, vmsg); + case VHOST_USER_GET_VRING_BASE: + return vu_get_vring_base_exec(dev, vmsg); + case VHOST_USER_SET_VRING_KICK: + return vu_set_vring_kick_exec(dev, vmsg); + case VHOST_USER_SET_VRING_CALL: + return vu_set_vring_call_exec(dev, vmsg); + case VHOST_USER_SET_VRING_ERR: + return vu_set_vring_err_exec(dev, vmsg); + case VHOST_USER_GET_QUEUE_NUM: + return vu_get_queue_num_exec(dev, vmsg); + case VHOST_USER_SET_VRING_ENABLE: + return vu_set_vring_enable_exec(dev, vmsg); + case VHOST_USER_SET_SLAVE_REQ_FD: + return vu_set_slave_req_fd(dev, vmsg); + case VHOST_USER_GET_CONFIG: + return vu_get_config(dev, vmsg); + case VHOST_USER_SET_CONFIG: + return vu_set_config(dev, vmsg); + case VHOST_USER_NONE: + /* if you need processing before exit, override iface->process_msg */ + exit(0); + case VHOST_USER_POSTCOPY_ADVISE: + return vu_set_postcopy_advise(dev, vmsg); + case VHOST_USER_POSTCOPY_LISTEN: + return vu_set_postcopy_listen(dev, vmsg); + case VHOST_USER_POSTCOPY_END: + return vu_set_postcopy_end(dev, vmsg); + case VHOST_USER_GET_INFLIGHT_FD: + return vu_get_inflight_fd(dev, vmsg); + case VHOST_USER_SET_INFLIGHT_FD: + return vu_set_inflight_fd(dev, vmsg); + case VHOST_USER_VRING_KICK: + return vu_handle_vring_kick(dev, vmsg); + case VHOST_USER_GET_MAX_MEM_SLOTS: + return vu_handle_get_max_memslots(dev, vmsg); + case VHOST_USER_ADD_MEM_REG: + return vu_add_mem_reg(dev, vmsg); + case VHOST_USER_REM_MEM_REG: + return vu_rem_mem_reg(dev, vmsg); + default: + vmsg_close_fds(vmsg); + vu_panic(dev, "Unhandled request: %d", vmsg->request); + } + + return false; +} + +bool +vu_dispatch(VuDev *dev) +{ + VhostUserMsg vmsg = { 0, }; + int reply_requested; + bool need_reply, success = false; + + if (!dev->read_msg(dev, dev->sock, &vmsg)) { + goto end; + } + + need_reply = vmsg.flags & VHOST_USER_NEED_REPLY_MASK; + + reply_requested = vu_process_message(dev, &vmsg); + if (!reply_requested && need_reply) { + vmsg_set_reply_u64(&vmsg, 0); + reply_requested = 1; + } + + if (!reply_requested) { + success = true; + goto end; + } + + if (!vu_send_reply(dev, dev->sock, &vmsg)) { + goto end; + } + + success = true; + +end: + free(vmsg.data); + return success; +} + +void +vu_deinit(VuDev *dev) +{ + int i; + + for (i = 0; i < dev->nregions; i++) { + VuDevRegion *r = &dev->regions[i]; + void *m = (void *) (uintptr_t) r->mmap_addr; + if (m != MAP_FAILED) { + munmap(m, r->size + r->mmap_offset); + } + } + dev->nregions = 0; + + for (i = 0; i < dev->max_queues; i++) { + VuVirtq *vq = &dev->vq[i]; + + if (vq->call_fd != -1) { + close(vq->call_fd); + vq->call_fd = -1; + } + + if (vq->kick_fd != -1) { + dev->remove_watch(dev, vq->kick_fd); + close(vq->kick_fd); + vq->kick_fd = -1; + } + + if (vq->err_fd != -1) { + close(vq->err_fd); + vq->err_fd = -1; + } + + if (vq->resubmit_list) { + free(vq->resubmit_list); + vq->resubmit_list = NULL; + } + + vq->inflight = NULL; + } + + if (dev->inflight_info.addr) { + munmap(dev->inflight_info.addr, dev->inflight_info.size); + dev->inflight_info.addr = NULL; + } + + if (dev->inflight_info.fd > 0) { + close(dev->inflight_info.fd); + dev->inflight_info.fd = -1; + } + + vu_close_log(dev); + if (dev->slave_fd != -1) { + close(dev->slave_fd); + dev->slave_fd = -1; + } + pthread_mutex_destroy(&dev->slave_mutex); + + if (dev->sock != -1) { + close(dev->sock); + } + + free(dev->vq); + dev->vq = NULL; +} + +bool +vu_init(VuDev *dev, + uint16_t max_queues, + int socket, + vu_panic_cb panic, + vu_read_msg_cb read_msg, + vu_set_watch_cb set_watch, + vu_remove_watch_cb remove_watch, + const VuDevIface *iface) +{ + uint16_t i; + + assert(max_queues > 0); + assert(socket >= 0); + assert(set_watch); + assert(remove_watch); + assert(iface); + assert(panic); + + memset(dev, 0, sizeof(*dev)); + + dev->sock = socket; + dev->panic = panic; + dev->read_msg = read_msg ? read_msg : vu_message_read_default; + dev->set_watch = set_watch; + dev->remove_watch = remove_watch; + dev->iface = iface; + dev->log_call_fd = -1; + pthread_mutex_init(&dev->slave_mutex, NULL); + dev->slave_fd = -1; + dev->max_queues = max_queues; + + dev->vq = malloc(max_queues * sizeof(dev->vq[0])); + if (!dev->vq) { + DPRINT("%s: failed to malloc virtqueues\n", __func__); + return false; + } + + for (i = 0; i < max_queues; i++) { + dev->vq[i] = (VuVirtq) { + .call_fd = -1, .kick_fd = -1, .err_fd = -1, + .notification = true, + }; + } + + return true; +} + +VuVirtq * +vu_get_queue(VuDev *dev, int qidx) +{ + assert(qidx < dev->max_queues); + return &dev->vq[qidx]; +} + +bool +vu_queue_enabled(VuDev *dev, VuVirtq *vq) +{ + return vq->enable; +} + +bool +vu_queue_started(const VuDev *dev, const VuVirtq *vq) +{ + return vq->started; +} + +static inline uint16_t +vring_avail_flags(VuVirtq *vq) +{ + return le16toh(vq->vring.avail->flags); +} + +static inline uint16_t +vring_avail_idx(VuVirtq *vq) +{ + vq->shadow_avail_idx = le16toh(vq->vring.avail->idx); + + return vq->shadow_avail_idx; +} + +static inline uint16_t +vring_avail_ring(VuVirtq *vq, int i) +{ + return le16toh(vq->vring.avail->ring[i]); +} + +static inline uint16_t +vring_get_used_event(VuVirtq *vq) +{ + return vring_avail_ring(vq, vq->vring.num); +} + +static int +virtqueue_num_heads(VuDev *dev, VuVirtq *vq, unsigned int idx) +{ + uint16_t num_heads = vring_avail_idx(vq) - idx; + + /* Check it isn't doing very strange things with descriptor numbers. */ + if (num_heads > vq->vring.num) { + vu_panic(dev, "Guest moved used index from %u to %u", + idx, vq->shadow_avail_idx); + return -1; + } + if (num_heads) { + /* On success, callers read a descriptor at vq->last_avail_idx. + * Make sure descriptor read does not bypass avail index read. */ + smp_rmb(); + } + + return num_heads; +} + +static bool +virtqueue_get_head(VuDev *dev, VuVirtq *vq, + unsigned int idx, unsigned int *head) +{ + /* Grab the next descriptor number they're advertising, and increment + * the index we've seen. */ + *head = vring_avail_ring(vq, idx % vq->vring.num); + + /* If their number is silly, that's a fatal mistake. */ + if (*head >= vq->vring.num) { + vu_panic(dev, "Guest says index %u is available", *head); + return false; + } + + return true; +} + +static int +virtqueue_read_indirect_desc(VuDev *dev, struct vring_desc *desc, + uint64_t addr, size_t len) +{ + struct vring_desc *ori_desc; + uint64_t read_len; + + if (len > (VIRTQUEUE_MAX_SIZE * sizeof(struct vring_desc))) { + return -1; + } + + if (len == 0) { + return -1; + } + + while (len) { + read_len = len; + ori_desc = vu_gpa_to_va(dev, &read_len, addr); + if (!ori_desc) { + return -1; + } + + memcpy(desc, ori_desc, read_len); + len -= read_len; + addr += read_len; + desc += read_len; + } + + return 0; +} + +enum { + VIRTQUEUE_READ_DESC_ERROR = -1, + VIRTQUEUE_READ_DESC_DONE = 0, /* end of chain */ + VIRTQUEUE_READ_DESC_MORE = 1, /* more buffers in chain */ +}; + +static int +virtqueue_read_next_desc(VuDev *dev, struct vring_desc *desc, + int i, unsigned int max, unsigned int *next) +{ + /* If this descriptor says it doesn't chain, we're done. */ + if (!(le16toh(desc[i].flags) & VRING_DESC_F_NEXT)) { + return VIRTQUEUE_READ_DESC_DONE; + } + + /* Check they're not leading us off end of descriptors. */ + *next = le16toh(desc[i].next); + /* Make sure compiler knows to grab that: we don't want it changing! */ + smp_wmb(); + + if (*next >= max) { + vu_panic(dev, "Desc next is %u", *next); + return VIRTQUEUE_READ_DESC_ERROR; + } + + return VIRTQUEUE_READ_DESC_MORE; +} + +void +vu_queue_get_avail_bytes(VuDev *dev, VuVirtq *vq, unsigned int *in_bytes, + unsigned int *out_bytes, + unsigned max_in_bytes, unsigned max_out_bytes) +{ + unsigned int idx; + unsigned int total_bufs, in_total, out_total; + int rc; + + idx = vq->last_avail_idx; + + total_bufs = in_total = out_total = 0; + if (unlikely(dev->broken) || + unlikely(!vq->vring.avail)) { + goto done; + } + + while ((rc = virtqueue_num_heads(dev, vq, idx)) > 0) { + unsigned int max, desc_len, num_bufs, indirect = 0; + uint64_t desc_addr, read_len; + struct vring_desc *desc; + struct vring_desc desc_buf[VIRTQUEUE_MAX_SIZE]; + unsigned int i; + + max = vq->vring.num; + num_bufs = total_bufs; + if (!virtqueue_get_head(dev, vq, idx++, &i)) { + goto err; + } + desc = vq->vring.desc; + + if (le16toh(desc[i].flags) & VRING_DESC_F_INDIRECT) { + if (le32toh(desc[i].len) % sizeof(struct vring_desc)) { + vu_panic(dev, "Invalid size for indirect buffer table"); + goto err; + } + + /* If we've got too many, that implies a descriptor loop. */ + if (num_bufs >= max) { + vu_panic(dev, "Looped descriptor"); + goto err; + } + + /* loop over the indirect descriptor table */ + indirect = 1; + desc_addr = le64toh(desc[i].addr); + desc_len = le32toh(desc[i].len); + max = desc_len / sizeof(struct vring_desc); + read_len = desc_len; + desc = vu_gpa_to_va(dev, &read_len, desc_addr); + if (unlikely(desc && read_len != desc_len)) { + /* Failed to use zero copy */ + desc = NULL; + if (!virtqueue_read_indirect_desc(dev, desc_buf, + desc_addr, + desc_len)) { + desc = desc_buf; + } + } + if (!desc) { + vu_panic(dev, "Invalid indirect buffer table"); + goto err; + } + num_bufs = i = 0; + } + + do { + /* If we've got too many, that implies a descriptor loop. */ + if (++num_bufs > max) { + vu_panic(dev, "Looped descriptor"); + goto err; + } + + if (le16toh(desc[i].flags) & VRING_DESC_F_WRITE) { + in_total += le32toh(desc[i].len); + } else { + out_total += le32toh(desc[i].len); + } + if (in_total >= max_in_bytes && out_total >= max_out_bytes) { + goto done; + } + rc = virtqueue_read_next_desc(dev, desc, i, max, &i); + } while (rc == VIRTQUEUE_READ_DESC_MORE); + + if (rc == VIRTQUEUE_READ_DESC_ERROR) { + goto err; + } + + if (!indirect) { + total_bufs = num_bufs; + } else { + total_bufs++; + } + } + if (rc < 0) { + goto err; + } +done: + if (in_bytes) { + *in_bytes = in_total; + } + if (out_bytes) { + *out_bytes = out_total; + } + return; + +err: + in_total = out_total = 0; + goto done; +} + +bool +vu_queue_avail_bytes(VuDev *dev, VuVirtq *vq, unsigned int in_bytes, + unsigned int out_bytes) +{ + unsigned int in_total, out_total; + + vu_queue_get_avail_bytes(dev, vq, &in_total, &out_total, + in_bytes, out_bytes); + + return in_bytes <= in_total && out_bytes <= out_total; +} + +/* Fetch avail_idx from VQ memory only when we really need to know if + * guest has added some buffers. */ +bool +vu_queue_empty(VuDev *dev, VuVirtq *vq) +{ + if (unlikely(dev->broken) || + unlikely(!vq->vring.avail)) { + return true; + } + + if (vq->shadow_avail_idx != vq->last_avail_idx) { + return false; + } + + return vring_avail_idx(vq) == vq->last_avail_idx; +} + +static bool +vring_notify(VuDev *dev, VuVirtq *vq) +{ + uint16_t old, new; + bool v; + + /* We need to expose used array entries before checking used event. */ + smp_mb(); + + /* Always notify when queue is empty (when feature acknowledge) */ + if (vu_has_feature(dev, VIRTIO_F_NOTIFY_ON_EMPTY) && + !vq->inuse && vu_queue_empty(dev, vq)) { + return true; + } + + if (!vu_has_feature(dev, VIRTIO_RING_F_EVENT_IDX)) { + return !(vring_avail_flags(vq) & VRING_AVAIL_F_NO_INTERRUPT); + } + + v = vq->signalled_used_valid; + vq->signalled_used_valid = true; + old = vq->signalled_used; + new = vq->signalled_used = vq->used_idx; + return !v || vring_need_event(vring_get_used_event(vq), new, old); +} + +static void _vu_queue_notify(VuDev *dev, VuVirtq *vq, bool sync) +{ + if (unlikely(dev->broken) || + unlikely(!vq->vring.avail)) { + return; + } + + if (!vring_notify(dev, vq)) { + DPRINT("skipped notify...\n"); + return; + } + + if (vq->call_fd < 0 && + vu_has_protocol_feature(dev, + VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS) && + vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_SLAVE_REQ)) { + VhostUserMsg vmsg = { + .request = VHOST_USER_SLAVE_VRING_CALL, + .flags = VHOST_USER_VERSION, + .size = sizeof(vmsg.payload.state), + .payload.state = { + .index = vq - dev->vq, + }, + }; + bool ack = sync && + vu_has_protocol_feature(dev, + VHOST_USER_PROTOCOL_F_REPLY_ACK); + + if (ack) { + vmsg.flags |= VHOST_USER_NEED_REPLY_MASK; + } + + vu_message_write(dev, dev->slave_fd, &vmsg); + if (ack) { + vu_message_read_default(dev, dev->slave_fd, &vmsg); + } + return; + } + + if (eventfd_write(vq->call_fd, 1) < 0) { + vu_panic(dev, "Error writing eventfd: %s", strerror(errno)); + } +} + +void vu_queue_notify(VuDev *dev, VuVirtq *vq) +{ + _vu_queue_notify(dev, vq, false); +} + +void vu_queue_notify_sync(VuDev *dev, VuVirtq *vq) +{ + _vu_queue_notify(dev, vq, true); +} + +static inline void +vring_used_flags_set_bit(VuVirtq *vq, int mask) +{ + uint16_t *flags; + + flags = (uint16_t *)((char*)vq->vring.used + + offsetof(struct vring_used, flags)); + *flags = htole16(le16toh(*flags) | mask); +} + +static inline void +vring_used_flags_unset_bit(VuVirtq *vq, int mask) +{ + uint16_t *flags; + + flags = (uint16_t *)((char*)vq->vring.used + + offsetof(struct vring_used, flags)); + *flags = htole16(le16toh(*flags) & ~mask); +} + +static inline void +vring_set_avail_event(VuVirtq *vq, uint16_t val) +{ + uint16_t *avail; + + if (!vq->notification) { + return; + } + + avail = (uint16_t *)&vq->vring.used->ring[vq->vring.num]; + *avail = htole16(val); +} + +void +vu_queue_set_notification(VuDev *dev, VuVirtq *vq, int enable) +{ + vq->notification = enable; + if (vu_has_feature(dev, VIRTIO_RING_F_EVENT_IDX)) { + vring_set_avail_event(vq, vring_avail_idx(vq)); + } else if (enable) { + vring_used_flags_unset_bit(vq, VRING_USED_F_NO_NOTIFY); + } else { + vring_used_flags_set_bit(vq, VRING_USED_F_NO_NOTIFY); + } + if (enable) { + /* Expose avail event/used flags before caller checks the avail idx. */ + smp_mb(); + } +} + +static bool +virtqueue_map_desc(VuDev *dev, + unsigned int *p_num_sg, struct iovec *iov, + unsigned int max_num_sg, bool is_write, + uint64_t pa, size_t sz) +{ + unsigned num_sg = *p_num_sg; + + assert(num_sg <= max_num_sg); + + if (!sz) { + vu_panic(dev, "virtio: zero sized buffers are not allowed"); + return false; + } + + while (sz) { + uint64_t len = sz; + + if (num_sg == max_num_sg) { + vu_panic(dev, "virtio: too many descriptors in indirect table"); + return false; + } + + iov[num_sg].iov_base = vu_gpa_to_va(dev, &len, pa); + if (iov[num_sg].iov_base == NULL) { + vu_panic(dev, "virtio: invalid address for buffers"); + return false; + } + iov[num_sg].iov_len = len; + num_sg++; + sz -= len; + pa += len; + } + + *p_num_sg = num_sg; + return true; +} + +static void * +virtqueue_alloc_element(size_t sz, + unsigned out_num, unsigned in_num) +{ + VuVirtqElement *elem; + size_t in_sg_ofs = ALIGN_UP(sz, __alignof__(elem->in_sg[0])); + size_t out_sg_ofs = in_sg_ofs + in_num * sizeof(elem->in_sg[0]); + size_t out_sg_end = out_sg_ofs + out_num * sizeof(elem->out_sg[0]); + + assert(sz >= sizeof(VuVirtqElement)); + elem = malloc(out_sg_end); + elem->out_num = out_num; + elem->in_num = in_num; + elem->in_sg = (void *)elem + in_sg_ofs; + elem->out_sg = (void *)elem + out_sg_ofs; + return elem; +} + +static void * +vu_queue_map_desc(VuDev *dev, VuVirtq *vq, unsigned int idx, size_t sz) +{ + struct vring_desc *desc = vq->vring.desc; + uint64_t desc_addr, read_len; + unsigned int desc_len; + unsigned int max = vq->vring.num; + unsigned int i = idx; + VuVirtqElement *elem; + unsigned int out_num = 0, in_num = 0; + struct iovec iov[VIRTQUEUE_MAX_SIZE]; + struct vring_desc desc_buf[VIRTQUEUE_MAX_SIZE]; + int rc; + + if (le16toh(desc[i].flags) & VRING_DESC_F_INDIRECT) { + if (le32toh(desc[i].len) % sizeof(struct vring_desc)) { + vu_panic(dev, "Invalid size for indirect buffer table"); + return NULL; + } + + /* loop over the indirect descriptor table */ + desc_addr = le64toh(desc[i].addr); + desc_len = le32toh(desc[i].len); + max = desc_len / sizeof(struct vring_desc); + read_len = desc_len; + desc = vu_gpa_to_va(dev, &read_len, desc_addr); + if (unlikely(desc && read_len != desc_len)) { + /* Failed to use zero copy */ + desc = NULL; + if (!virtqueue_read_indirect_desc(dev, desc_buf, + desc_addr, + desc_len)) { + desc = desc_buf; + } + } + if (!desc) { + vu_panic(dev, "Invalid indirect buffer table"); + return NULL; + } + i = 0; + } + + /* Collect all the descriptors */ + do { + if (le16toh(desc[i].flags) & VRING_DESC_F_WRITE) { + if (!virtqueue_map_desc(dev, &in_num, iov + out_num, + VIRTQUEUE_MAX_SIZE - out_num, true, + le64toh(desc[i].addr), + le32toh(desc[i].len))) { + return NULL; + } + } else { + if (in_num) { + vu_panic(dev, "Incorrect order for descriptors"); + return NULL; + } + if (!virtqueue_map_desc(dev, &out_num, iov, + VIRTQUEUE_MAX_SIZE, false, + le64toh(desc[i].addr), + le32toh(desc[i].len))) { + return NULL; + } + } + + /* If we've got too many, that implies a descriptor loop. */ + if ((in_num + out_num) > max) { + vu_panic(dev, "Looped descriptor"); + return NULL; + } + rc = virtqueue_read_next_desc(dev, desc, i, max, &i); + } while (rc == VIRTQUEUE_READ_DESC_MORE); + + if (rc == VIRTQUEUE_READ_DESC_ERROR) { + vu_panic(dev, "read descriptor error"); + return NULL; + } + + /* Now copy what we have collected and mapped */ + elem = virtqueue_alloc_element(sz, out_num, in_num); + elem->index = idx; + for (i = 0; i < out_num; i++) { + elem->out_sg[i] = iov[i]; + } + for (i = 0; i < in_num; i++) { + elem->in_sg[i] = iov[out_num + i]; + } + + return elem; +} + +static int +vu_queue_inflight_get(VuDev *dev, VuVirtq *vq, int desc_idx) +{ + if (!vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD)) { + return 0; + } + + if (unlikely(!vq->inflight)) { + return -1; + } + + vq->inflight->desc[desc_idx].counter = vq->counter++; + vq->inflight->desc[desc_idx].inflight = 1; + + return 0; +} + +static int +vu_queue_inflight_pre_put(VuDev *dev, VuVirtq *vq, int desc_idx) +{ + if (!vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD)) { + return 0; + } + + if (unlikely(!vq->inflight)) { + return -1; + } + + vq->inflight->last_batch_head = desc_idx; + + return 0; +} + +static int +vu_queue_inflight_post_put(VuDev *dev, VuVirtq *vq, int desc_idx) +{ + if (!vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD)) { + return 0; + } + + if (unlikely(!vq->inflight)) { + return -1; + } + + barrier(); + + vq->inflight->desc[desc_idx].inflight = 0; + + barrier(); + + vq->inflight->used_idx = vq->used_idx; + + return 0; +} + +void * +vu_queue_pop(VuDev *dev, VuVirtq *vq, size_t sz) +{ + int i; + unsigned int head; + VuVirtqElement *elem; + + if (unlikely(dev->broken) || + unlikely(!vq->vring.avail)) { + return NULL; + } + + if (unlikely(vq->resubmit_list && vq->resubmit_num > 0)) { + i = (--vq->resubmit_num); + elem = vu_queue_map_desc(dev, vq, vq->resubmit_list[i].index, sz); + + if (!vq->resubmit_num) { + free(vq->resubmit_list); + vq->resubmit_list = NULL; + } + + return elem; + } + + if (vu_queue_empty(dev, vq)) { + return NULL; + } + /* + * Needed after virtio_queue_empty(), see comment in + * virtqueue_num_heads(). + */ + smp_rmb(); + + if (vq->inuse >= vq->vring.num) { + vu_panic(dev, "Virtqueue size exceeded"); + return NULL; + } + + if (!virtqueue_get_head(dev, vq, vq->last_avail_idx++, &head)) { + return NULL; + } + + if (vu_has_feature(dev, VIRTIO_RING_F_EVENT_IDX)) { + vring_set_avail_event(vq, vq->last_avail_idx); + } + + elem = vu_queue_map_desc(dev, vq, head, sz); + + if (!elem) { + return NULL; + } + + vq->inuse++; + + vu_queue_inflight_get(dev, vq, head); + + return elem; +} + +static void +vu_queue_detach_element(VuDev *dev, VuVirtq *vq, VuVirtqElement *elem, + size_t len) +{ + vq->inuse--; + /* unmap, when DMA support is added */ +} + +void +vu_queue_unpop(VuDev *dev, VuVirtq *vq, VuVirtqElement *elem, + size_t len) +{ + vq->last_avail_idx--; + vu_queue_detach_element(dev, vq, elem, len); +} + +bool +vu_queue_rewind(VuDev *dev, VuVirtq *vq, unsigned int num) +{ + if (num > vq->inuse) { + return false; + } + vq->last_avail_idx -= num; + vq->inuse -= num; + return true; +} + +static inline +void vring_used_write(VuDev *dev, VuVirtq *vq, + struct vring_used_elem *uelem, int i) +{ + struct vring_used *used = vq->vring.used; + + used->ring[i] = *uelem; + vu_log_write(dev, vq->vring.log_guest_addr + + offsetof(struct vring_used, ring[i]), + sizeof(used->ring[i])); +} + + +static void +vu_log_queue_fill(VuDev *dev, VuVirtq *vq, + const VuVirtqElement *elem, + unsigned int len) +{ + struct vring_desc *desc = vq->vring.desc; + unsigned int i, max, min, desc_len; + uint64_t desc_addr, read_len; + struct vring_desc desc_buf[VIRTQUEUE_MAX_SIZE]; + unsigned num_bufs = 0; + + max = vq->vring.num; + i = elem->index; + + if (le16toh(desc[i].flags) & VRING_DESC_F_INDIRECT) { + if (le32toh(desc[i].len) % sizeof(struct vring_desc)) { + vu_panic(dev, "Invalid size for indirect buffer table"); + return; + } + + /* loop over the indirect descriptor table */ + desc_addr = le64toh(desc[i].addr); + desc_len = le32toh(desc[i].len); + max = desc_len / sizeof(struct vring_desc); + read_len = desc_len; + desc = vu_gpa_to_va(dev, &read_len, desc_addr); + if (unlikely(desc && read_len != desc_len)) { + /* Failed to use zero copy */ + desc = NULL; + if (!virtqueue_read_indirect_desc(dev, desc_buf, + desc_addr, + desc_len)) { + desc = desc_buf; + } + } + if (!desc) { + vu_panic(dev, "Invalid indirect buffer table"); + return; + } + i = 0; + } + + do { + if (++num_bufs > max) { + vu_panic(dev, "Looped descriptor"); + return; + } + + if (le16toh(desc[i].flags) & VRING_DESC_F_WRITE) { + min = MIN(le32toh(desc[i].len), len); + vu_log_write(dev, le64toh(desc[i].addr), min); + len -= min; + } + + } while (len > 0 && + (virtqueue_read_next_desc(dev, desc, i, max, &i) + == VIRTQUEUE_READ_DESC_MORE)); +} + +void +vu_queue_fill(VuDev *dev, VuVirtq *vq, + const VuVirtqElement *elem, + unsigned int len, unsigned int idx) +{ + struct vring_used_elem uelem; + + if (unlikely(dev->broken) || + unlikely(!vq->vring.avail)) { + return; + } + + vu_log_queue_fill(dev, vq, elem, len); + + idx = (idx + vq->used_idx) % vq->vring.num; + + uelem.id = htole32(elem->index); + uelem.len = htole32(len); + vring_used_write(dev, vq, &uelem, idx); +} + +static inline +void vring_used_idx_set(VuDev *dev, VuVirtq *vq, uint16_t val) +{ + vq->vring.used->idx = htole16(val); + vu_log_write(dev, + vq->vring.log_guest_addr + offsetof(struct vring_used, idx), + sizeof(vq->vring.used->idx)); + + vq->used_idx = val; +} + +void +vu_queue_flush(VuDev *dev, VuVirtq *vq, unsigned int count) +{ + uint16_t old, new; + + if (unlikely(dev->broken) || + unlikely(!vq->vring.avail)) { + return; + } + + /* Make sure buffer is written before we update index. */ + smp_wmb(); + + old = vq->used_idx; + new = old + count; + vring_used_idx_set(dev, vq, new); + vq->inuse -= count; + if (unlikely((int16_t)(new - vq->signalled_used) < (uint16_t)(new - old))) { + vq->signalled_used_valid = false; + } +} + +void +vu_queue_push(VuDev *dev, VuVirtq *vq, + const VuVirtqElement *elem, unsigned int len) +{ + vu_queue_fill(dev, vq, elem, len, 0); + vu_queue_inflight_pre_put(dev, vq, elem->index); + vu_queue_flush(dev, vq, 1); + vu_queue_inflight_post_put(dev, vq, elem->index); +} |