blob: e089d4d546cfe65c0cc72175347bb1ca18b434bd [file] [log] [blame]
/*
* VDUSE (vDPA Device in Userspace) library
*
* Copyright (C) 2022 Bytedance Inc. and/or its affiliates. All rights reserved.
* Portions of codes and concepts borrowed from libvhost-user.c, so:
* Copyright IBM, Corp. 2007
* Copyright (c) 2016 Red Hat, Inc.
*
* Author:
* Xie Yongji <xieyongji@bytedance.com>
* Anthony Liguori <aliguori@us.ibm.com>
* Marc-André 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.
*/
#include <stdlib.h>
#include <stdio.h>
#include <stdbool.h>
#include <stddef.h>
#include <errno.h>
#include <string.h>
#include <assert.h>
#include <endian.h>
#include <unistd.h>
#include <limits.h>
#include <fcntl.h>
#include <inttypes.h>
#include <sys/ioctl.h>
#include <sys/eventfd.h>
#include <sys/mman.h>
#include "include/atomic.h"
#include "linux-headers/linux/virtio_ring.h"
#include "linux-headers/linux/virtio_config.h"
#include "linux-headers/linux/vduse.h"
#include "libvduse.h"
#define VDUSE_VQ_ALIGN 4096
#define MAX_IOVA_REGIONS 256
#define LOG_ALIGNMENT 64
/* 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
typedef struct VduseDescStateSplit {
uint8_t inflight;
uint8_t padding[5];
uint16_t next;
uint64_t counter;
} VduseDescStateSplit;
typedef struct VduseVirtqLogInflight {
uint64_t features;
uint16_t version;
uint16_t desc_num;
uint16_t last_batch_head;
uint16_t used_idx;
VduseDescStateSplit desc[];
} VduseVirtqLogInflight;
typedef struct VduseVirtqLog {
VduseVirtqLogInflight inflight;
} VduseVirtqLog;
typedef struct VduseVirtqInflightDesc {
uint16_t index;
uint64_t counter;
} VduseVirtqInflightDesc;
typedef struct VduseRing {
unsigned int num;
uint64_t desc_addr;
uint64_t avail_addr;
uint64_t used_addr;
struct vring_desc *desc;
struct vring_avail *avail;
struct vring_used *used;
} VduseRing;
struct VduseVirtq {
VduseRing vring;
uint16_t last_avail_idx;
uint16_t shadow_avail_idx;
uint16_t used_idx;
uint16_t signalled_used;
bool signalled_used_valid;
int index;
int inuse;
bool ready;
int fd;
VduseDev *dev;
VduseVirtqInflightDesc *resubmit_list;
uint16_t resubmit_num;
uint64_t counter;
VduseVirtqLog *log;
};
typedef struct VduseIovaRegion {
uint64_t iova;
uint64_t size;
uint64_t mmap_offset;
uint64_t mmap_addr;
} VduseIovaRegion;
struct VduseDev {
VduseVirtq *vqs;
VduseIovaRegion regions[MAX_IOVA_REGIONS];
int num_regions;
char *name;
uint32_t device_id;
uint32_t vendor_id;
uint16_t num_queues;
uint16_t queue_size;
uint64_t features;
const VduseOps *ops;
int fd;
int ctrl_fd;
void *priv;
void *log;
};
static inline size_t vduse_vq_log_size(uint16_t queue_size)
{
return ALIGN_UP(sizeof(VduseDescStateSplit) * queue_size +
sizeof(VduseVirtqLogInflight), LOG_ALIGNMENT);
}
static void *vduse_log_get(const char *filename, size_t size)
{
void *ptr = MAP_FAILED;
int fd;
fd = open(filename, O_RDWR | O_CREAT, 0600);
if (fd == -1) {
return MAP_FAILED;
}
if (ftruncate(fd, size) == -1) {
goto out;
}
ptr = mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
out:
close(fd);
return ptr;
}
static inline bool has_feature(uint64_t features, unsigned int fbit)
{
assert(fbit < 64);
return !!(features & (1ULL << fbit));
}
static inline bool vduse_dev_has_feature(VduseDev *dev, unsigned int fbit)
{
return has_feature(dev->features, fbit);
}
uint64_t vduse_get_virtio_features(void)
{
return (1ULL << VIRTIO_F_IOMMU_PLATFORM) |
(1ULL << VIRTIO_F_VERSION_1) |
(1ULL << VIRTIO_F_NOTIFY_ON_EMPTY) |
(1ULL << VIRTIO_RING_F_EVENT_IDX) |
(1ULL << VIRTIO_RING_F_INDIRECT_DESC);
}
VduseDev *vduse_queue_get_dev(VduseVirtq *vq)
{
return vq->dev;
}
int vduse_queue_get_fd(VduseVirtq *vq)
{
return vq->fd;
}
void *vduse_dev_get_priv(VduseDev *dev)
{
return dev->priv;
}
VduseVirtq *vduse_dev_get_queue(VduseDev *dev, int index)
{
return &dev->vqs[index];
}
int vduse_dev_get_fd(VduseDev *dev)
{
return dev->fd;
}
static int vduse_inject_irq(VduseDev *dev, int index)
{
return ioctl(dev->fd, VDUSE_VQ_INJECT_IRQ, &index);
}
static int inflight_desc_compare(const void *a, const void *b)
{
VduseVirtqInflightDesc *desc0 = (VduseVirtqInflightDesc *)a,
*desc1 = (VduseVirtqInflightDesc *)b;
if (desc1->counter > desc0->counter &&
(desc1->counter - desc0->counter) < VIRTQUEUE_MAX_SIZE * 2) {
return 1;
}
return -1;
}
static int vduse_queue_check_inflights(VduseVirtq *vq)
{
int i = 0;
VduseDev *dev = vq->dev;
vq->used_idx = le16toh(vq->vring.used->idx);
vq->resubmit_num = 0;
vq->resubmit_list = NULL;
vq->counter = 0;
if (unlikely(vq->log->inflight.used_idx != vq->used_idx)) {
if (vq->log->inflight.last_batch_head > VIRTQUEUE_MAX_SIZE) {
return -1;
}
vq->log->inflight.desc[vq->log->inflight.last_batch_head].inflight = 0;
barrier();
vq->log->inflight.used_idx = vq->used_idx;
}
for (i = 0; i < vq->log->inflight.desc_num; i++) {
if (vq->log->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(VduseVirtqInflightDesc));
if (!vq->resubmit_list) {
return -1;
}
for (i = 0; i < vq->log->inflight.desc_num; i++) {
if (vq->log->inflight.desc[i].inflight) {
vq->resubmit_list[vq->resubmit_num].index = i;
vq->resubmit_list[vq->resubmit_num].counter =
vq->log->inflight.desc[i].counter;
vq->resubmit_num++;
}
}
if (vq->resubmit_num > 1) {
qsort(vq->resubmit_list, vq->resubmit_num,
sizeof(VduseVirtqInflightDesc), inflight_desc_compare);
}
vq->counter = vq->resubmit_list[0].counter + 1;
}
vduse_inject_irq(dev, vq->index);
return 0;
}
static int vduse_queue_inflight_get(VduseVirtq *vq, int desc_idx)
{
vq->log->inflight.desc[desc_idx].counter = vq->counter++;
barrier();
vq->log->inflight.desc[desc_idx].inflight = 1;
return 0;
}
static int vduse_queue_inflight_pre_put(VduseVirtq *vq, int desc_idx)
{
vq->log->inflight.last_batch_head = desc_idx;
return 0;
}
static int vduse_queue_inflight_post_put(VduseVirtq *vq, int desc_idx)
{
vq->log->inflight.desc[desc_idx].inflight = 0;
barrier();
vq->log->inflight.used_idx = vq->used_idx;
return 0;
}
static void vduse_iova_remove_region(VduseDev *dev, uint64_t start,
uint64_t last)
{
int i;
if (last == start) {
return;
}
for (i = 0; i < MAX_IOVA_REGIONS; i++) {
if (!dev->regions[i].mmap_addr) {
continue;
}
if (start <= dev->regions[i].iova &&
last >= (dev->regions[i].iova + dev->regions[i].size - 1)) {
munmap((void *)(uintptr_t)dev->regions[i].mmap_addr,
dev->regions[i].mmap_offset + dev->regions[i].size);
dev->regions[i].mmap_addr = 0;
dev->num_regions--;
}
}
}
static int vduse_iova_add_region(VduseDev *dev, int fd,
uint64_t offset, uint64_t start,
uint64_t last, int prot)
{
int i;
uint64_t size = last - start + 1;
void *mmap_addr = mmap(0, size + offset, prot, MAP_SHARED, fd, 0);
if (mmap_addr == MAP_FAILED) {
close(fd);
return -EINVAL;
}
for (i = 0; i < MAX_IOVA_REGIONS; i++) {
if (!dev->regions[i].mmap_addr) {
dev->regions[i].mmap_addr = (uint64_t)(uintptr_t)mmap_addr;
dev->regions[i].mmap_offset = offset;
dev->regions[i].iova = start;
dev->regions[i].size = size;
dev->num_regions++;
break;
}
}
assert(i < MAX_IOVA_REGIONS);
close(fd);
return 0;
}
static int perm_to_prot(uint8_t perm)
{
int prot = 0;
switch (perm) {
case VDUSE_ACCESS_WO:
prot |= PROT_WRITE;
break;
case VDUSE_ACCESS_RO:
prot |= PROT_READ;
break;
case VDUSE_ACCESS_RW:
prot |= PROT_READ | PROT_WRITE;
break;
default:
break;
}
return prot;
}
static inline void *iova_to_va(VduseDev *dev, uint64_t *plen, uint64_t iova)
{
int i, ret;
struct vduse_iotlb_entry entry;
for (i = 0; i < MAX_IOVA_REGIONS; i++) {
VduseIovaRegion *r = &dev->regions[i];
if (!r->mmap_addr) {
continue;
}
if ((iova >= r->iova) && (iova < (r->iova + r->size))) {
if ((iova + *plen) > (r->iova + r->size)) {
*plen = r->iova + r->size - iova;
}
return (void *)(uintptr_t)(iova - r->iova +
r->mmap_addr + r->mmap_offset);
}
}
entry.start = iova;
entry.last = iova + 1;
ret = ioctl(dev->fd, VDUSE_IOTLB_GET_FD, &entry);
if (ret < 0) {
return NULL;
}
if (!vduse_iova_add_region(dev, ret, entry.offset, entry.start,
entry.last, perm_to_prot(entry.perm))) {
return iova_to_va(dev, plen, iova);
}
return NULL;
}
static inline uint16_t vring_avail_flags(VduseVirtq *vq)
{
return le16toh(vq->vring.avail->flags);
}
static inline uint16_t vring_avail_idx(VduseVirtq *vq)
{
vq->shadow_avail_idx = le16toh(vq->vring.avail->idx);
return vq->shadow_avail_idx;
}
static inline uint16_t vring_avail_ring(VduseVirtq *vq, int i)
{
return le16toh(vq->vring.avail->ring[i]);
}
static inline uint16_t vring_get_used_event(VduseVirtq *vq)
{
return vring_avail_ring(vq, vq->vring.num);
}
static bool vduse_queue_get_head(VduseVirtq *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) {
fprintf(stderr, "Guest says index %u is available\n", *head);
return false;
}
return true;
}
static int
vduse_queue_read_indirect_desc(VduseDev *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 = iova_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 vduse_queue_read_next_desc(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 = desc[i].next;
/* Make sure compiler knows to grab that: we don't want it changing! */
smp_wmb();
if (*next >= max) {
fprintf(stderr, "Desc next is %u\n", *next);
return VIRTQUEUE_READ_DESC_ERROR;
}
return VIRTQUEUE_READ_DESC_MORE;
}
/*
* Fetch avail_idx from VQ memory only when we really need to know if
* guest has added some buffers.
*/
static bool vduse_queue_empty(VduseVirtq *vq)
{
if (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 vduse_queue_should_notify(VduseVirtq *vq)
{
VduseDev *dev = vq->dev;
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 (vduse_dev_has_feature(dev, VIRTIO_F_NOTIFY_ON_EMPTY) &&
!vq->inuse && vduse_queue_empty(vq)) {
return true;
}
if (!vduse_dev_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);
}
void vduse_queue_notify(VduseVirtq *vq)
{
VduseDev *dev = vq->dev;
if (unlikely(!vq->vring.avail)) {
return;
}
if (!vduse_queue_should_notify(vq)) {
return;
}
if (vduse_inject_irq(dev, vq->index) < 0) {
fprintf(stderr, "Error inject irq for vq %d: %s\n",
vq->index, strerror(errno));
}
}
static inline void vring_set_avail_event(VduseVirtq *vq, uint16_t val)
{
*((uint16_t *)&vq->vring.used->ring[vq->vring.num]) = htole16(val);
}
static bool vduse_queue_map_single_desc(VduseVirtq *vq, 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;
VduseDev *dev = vq->dev;
assert(num_sg <= max_num_sg);
if (!sz) {
fprintf(stderr, "virtio: zero sized buffers are not allowed\n");
return false;
}
while (sz) {
uint64_t len = sz;
if (num_sg == max_num_sg) {
fprintf(stderr,
"virtio: too many descriptors in indirect table\n");
return false;
}
iov[num_sg].iov_base = iova_to_va(dev, &len, pa);
if (iov[num_sg].iov_base == NULL) {
fprintf(stderr, "virtio: invalid address for buffers\n");
return false;
}
iov[num_sg++].iov_len = len;
sz -= len;
pa += len;
}
*p_num_sg = num_sg;
return true;
}
static void *vduse_queue_alloc_element(size_t sz, unsigned out_num,
unsigned in_num)
{
VduseVirtqElement *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(VduseVirtqElement));
elem = malloc(out_sg_end);
if (!elem) {
return NULL;
}
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 *vduse_queue_map_desc(VduseVirtq *vq, unsigned int idx, size_t sz)
{
struct vring_desc *desc = vq->vring.desc;
VduseDev *dev = vq->dev;
uint64_t desc_addr, read_len;
unsigned int desc_len;
unsigned int max = vq->vring.num;
unsigned int i = idx;
VduseVirtqElement *elem;
struct iovec iov[VIRTQUEUE_MAX_SIZE];
struct vring_desc desc_buf[VIRTQUEUE_MAX_SIZE];
unsigned int out_num = 0, in_num = 0;
int rc;
if (le16toh(desc[i].flags) & VRING_DESC_F_INDIRECT) {
if (le32toh(desc[i].len) % sizeof(struct vring_desc)) {
fprintf(stderr, "Invalid size for indirect buffer table\n");
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 = iova_to_va(dev, &read_len, desc_addr);
if (unlikely(desc && read_len != desc_len)) {
/* Failed to use zero copy */
desc = NULL;
if (!vduse_queue_read_indirect_desc(dev, desc_buf,
desc_addr,
desc_len)) {
desc = desc_buf;
}
}
if (!desc) {
fprintf(stderr, "Invalid indirect buffer table\n");
return NULL;
}
i = 0;
}
/* Collect all the descriptors */
do {
if (le16toh(desc[i].flags) & VRING_DESC_F_WRITE) {
if (!vduse_queue_map_single_desc(vq, &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) {
fprintf(stderr, "Incorrect order for descriptors\n");
return NULL;
}
if (!vduse_queue_map_single_desc(vq, &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) {
fprintf(stderr, "Looped descriptor\n");
return NULL;
}
rc = vduse_queue_read_next_desc(desc, i, max, &i);
} while (rc == VIRTQUEUE_READ_DESC_MORE);
if (rc == VIRTQUEUE_READ_DESC_ERROR) {
fprintf(stderr, "read descriptor error\n");
return NULL;
}
/* Now copy what we have collected and mapped */
elem = vduse_queue_alloc_element(sz, out_num, in_num);
if (!elem) {
fprintf(stderr, "read descriptor error\n");
return NULL;
}
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;
}
void *vduse_queue_pop(VduseVirtq *vq, size_t sz)
{
unsigned int head;
VduseVirtqElement *elem;
VduseDev *dev = vq->dev;
int i;
if (unlikely(!vq->vring.avail)) {
return NULL;
}
if (unlikely(vq->resubmit_list && vq->resubmit_num > 0)) {
i = (--vq->resubmit_num);
elem = vduse_queue_map_desc(vq, vq->resubmit_list[i].index, sz);
if (!vq->resubmit_num) {
free(vq->resubmit_list);
vq->resubmit_list = NULL;
}
return elem;
}
if (vduse_queue_empty(vq)) {
return NULL;
}
/* Needed after virtio_queue_empty() */
smp_rmb();
if (vq->inuse >= vq->vring.num) {
fprintf(stderr, "Virtqueue size exceeded: %d\n", vq->inuse);
return NULL;
}
if (!vduse_queue_get_head(vq, vq->last_avail_idx++, &head)) {
return NULL;
}
if (vduse_dev_has_feature(dev, VIRTIO_RING_F_EVENT_IDX)) {
vring_set_avail_event(vq, vq->last_avail_idx);
}
elem = vduse_queue_map_desc(vq, head, sz);
if (!elem) {
return NULL;
}
vq->inuse++;
vduse_queue_inflight_get(vq, head);
return elem;
}
static inline void vring_used_write(VduseVirtq *vq,
struct vring_used_elem *uelem, int i)
{
struct vring_used *used = vq->vring.used;
used->ring[i] = *uelem;
}
static void vduse_queue_fill(VduseVirtq *vq, const VduseVirtqElement *elem,
unsigned int len, unsigned int idx)
{
struct vring_used_elem uelem;
if (unlikely(!vq->vring.used)) {
return;
}
idx = (idx + vq->used_idx) % vq->vring.num;
uelem.id = htole32(elem->index);
uelem.len = htole32(len);
vring_used_write(vq, &uelem, idx);
}
static inline void vring_used_idx_set(VduseVirtq *vq, uint16_t val)
{
vq->vring.used->idx = htole16(val);
vq->used_idx = val;
}
static void vduse_queue_flush(VduseVirtq *vq, unsigned int count)
{
uint16_t old, new;
if (unlikely(!vq->vring.used)) {
return;
}
/* Make sure buffer is written before we update index. */
smp_wmb();
old = vq->used_idx;
new = old + count;
vring_used_idx_set(vq, new);
vq->inuse -= count;
if (unlikely((int16_t)(new - vq->signalled_used) < (uint16_t)(new - old))) {
vq->signalled_used_valid = false;
}
}
void vduse_queue_push(VduseVirtq *vq, const VduseVirtqElement *elem,
unsigned int len)
{
vduse_queue_fill(vq, elem, len, 0);
vduse_queue_inflight_pre_put(vq, elem->index);
vduse_queue_flush(vq, 1);
vduse_queue_inflight_post_put(vq, elem->index);
}
static int vduse_queue_update_vring(VduseVirtq *vq, uint64_t desc_addr,
uint64_t avail_addr, uint64_t used_addr)
{
struct VduseDev *dev = vq->dev;
uint64_t len;
len = sizeof(struct vring_desc);
vq->vring.desc = iova_to_va(dev, &len, desc_addr);
if (len != sizeof(struct vring_desc)) {
return -EINVAL;
}
len = sizeof(struct vring_avail);
vq->vring.avail = iova_to_va(dev, &len, avail_addr);
if (len != sizeof(struct vring_avail)) {
return -EINVAL;
}
len = sizeof(struct vring_used);
vq->vring.used = iova_to_va(dev, &len, used_addr);
if (len != sizeof(struct vring_used)) {
return -EINVAL;
}
if (!vq->vring.desc || !vq->vring.avail || !vq->vring.used) {
fprintf(stderr, "Failed to get vq[%d] iova mapping\n", vq->index);
return -EINVAL;
}
return 0;
}
static void vduse_queue_enable(VduseVirtq *vq)
{
struct VduseDev *dev = vq->dev;
struct vduse_vq_info vq_info;
struct vduse_vq_eventfd vq_eventfd;
int fd;
vq_info.index = vq->index;
if (ioctl(dev->fd, VDUSE_VQ_GET_INFO, &vq_info)) {
fprintf(stderr, "Failed to get vq[%d] info: %s\n",
vq->index, strerror(errno));
return;
}
if (!vq_info.ready) {
return;
}
vq->vring.num = vq_info.num;
vq->vring.desc_addr = vq_info.desc_addr;
vq->vring.avail_addr = vq_info.driver_addr;
vq->vring.used_addr = vq_info.device_addr;
if (vduse_queue_update_vring(vq, vq_info.desc_addr,
vq_info.driver_addr, vq_info.device_addr)) {
fprintf(stderr, "Failed to update vring for vq[%d]\n", vq->index);
return;
}
fd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
if (fd < 0) {
fprintf(stderr, "Failed to init eventfd for vq[%d]\n", vq->index);
return;
}
vq_eventfd.index = vq->index;
vq_eventfd.fd = fd;
if (ioctl(dev->fd, VDUSE_VQ_SETUP_KICKFD, &vq_eventfd)) {
fprintf(stderr, "Failed to setup kick fd for vq[%d]\n", vq->index);
close(fd);
return;
}
vq->fd = fd;
vq->signalled_used_valid = false;
vq->ready = true;
if (vduse_queue_check_inflights(vq)) {
fprintf(stderr, "Failed to check inflights for vq[%d]\n", vq->index);
close(fd);
return;
}
dev->ops->enable_queue(dev, vq);
}
static void vduse_queue_disable(VduseVirtq *vq)
{
struct VduseDev *dev = vq->dev;
struct vduse_vq_eventfd eventfd;
if (!vq->ready) {
return;
}
dev->ops->disable_queue(dev, vq);
eventfd.index = vq->index;
eventfd.fd = VDUSE_EVENTFD_DEASSIGN;
ioctl(dev->fd, VDUSE_VQ_SETUP_KICKFD, &eventfd);
close(vq->fd);
assert(vq->inuse == 0);
vq->vring.num = 0;
vq->vring.desc_addr = 0;
vq->vring.avail_addr = 0;
vq->vring.used_addr = 0;
vq->vring.desc = 0;
vq->vring.avail = 0;
vq->vring.used = 0;
vq->ready = false;
vq->fd = -1;
}
static void vduse_dev_start_dataplane(VduseDev *dev)
{
int i;
if (ioctl(dev->fd, VDUSE_DEV_GET_FEATURES, &dev->features)) {
fprintf(stderr, "Failed to get features: %s\n", strerror(errno));
return;
}
assert(vduse_dev_has_feature(dev, VIRTIO_F_VERSION_1));
for (i = 0; i < dev->num_queues; i++) {
vduse_queue_enable(&dev->vqs[i]);
}
}
static void vduse_dev_stop_dataplane(VduseDev *dev)
{
size_t log_size = dev->num_queues * vduse_vq_log_size(VIRTQUEUE_MAX_SIZE);
int i;
for (i = 0; i < dev->num_queues; i++) {
vduse_queue_disable(&dev->vqs[i]);
}
if (dev->log) {
memset(dev->log, 0, log_size);
}
dev->features = 0;
vduse_iova_remove_region(dev, 0, ULONG_MAX);
}
int vduse_dev_handler(VduseDev *dev)
{
struct vduse_dev_request req;
struct vduse_dev_response resp = { 0 };
VduseVirtq *vq;
int i, ret;
ret = read(dev->fd, &req, sizeof(req));
if (ret != sizeof(req)) {
fprintf(stderr, "Read request error [%d]: %s\n",
ret, strerror(errno));
return -errno;
}
resp.request_id = req.request_id;
switch (req.type) {
case VDUSE_GET_VQ_STATE:
vq = &dev->vqs[req.vq_state.index];
resp.vq_state.split.avail_index = vq->last_avail_idx;
resp.result = VDUSE_REQ_RESULT_OK;
break;
case VDUSE_SET_STATUS:
if (req.s.status & VIRTIO_CONFIG_S_DRIVER_OK) {
vduse_dev_start_dataplane(dev);
} else if (req.s.status == 0) {
vduse_dev_stop_dataplane(dev);
}
resp.result = VDUSE_REQ_RESULT_OK;
break;
case VDUSE_UPDATE_IOTLB:
/* The iova will be updated by iova_to_va() later, so just remove it */
vduse_iova_remove_region(dev, req.iova.start, req.iova.last);
for (i = 0; i < dev->num_queues; i++) {
VduseVirtq *vq = &dev->vqs[i];
if (vq->ready) {
if (vduse_queue_update_vring(vq, vq->vring.desc_addr,
vq->vring.avail_addr,
vq->vring.used_addr)) {
fprintf(stderr, "Failed to update vring for vq[%d]\n",
vq->index);
}
}
}
resp.result = VDUSE_REQ_RESULT_OK;
break;
default:
resp.result = VDUSE_REQ_RESULT_FAILED;
break;
}
ret = write(dev->fd, &resp, sizeof(resp));
if (ret != sizeof(resp)) {
fprintf(stderr, "Write request %d error [%d]: %s\n",
req.type, ret, strerror(errno));
return -errno;
}
return 0;
}
int vduse_dev_update_config(VduseDev *dev, uint32_t size,
uint32_t offset, char *buffer)
{
int ret;
struct vduse_config_data *data;
data = malloc(offsetof(struct vduse_config_data, buffer) + size);
if (!data) {
return -ENOMEM;
}
data->offset = offset;
data->length = size;
memcpy(data->buffer, buffer, size);
ret = ioctl(dev->fd, VDUSE_DEV_SET_CONFIG, data);
free(data);
if (ret) {
return -errno;
}
if (ioctl(dev->fd, VDUSE_DEV_INJECT_CONFIG_IRQ)) {
return -errno;
}
return 0;
}
int vduse_dev_setup_queue(VduseDev *dev, int index, int max_size)
{
VduseVirtq *vq = &dev->vqs[index];
struct vduse_vq_config vq_config = { 0 };
if (max_size > VIRTQUEUE_MAX_SIZE) {
return -EINVAL;
}
vq_config.index = vq->index;
vq_config.max_size = max_size;
if (ioctl(dev->fd, VDUSE_VQ_SETUP, &vq_config)) {
return -errno;
}
vduse_queue_enable(vq);
return 0;
}
int vduse_set_reconnect_log_file(VduseDev *dev, const char *filename)
{
size_t log_size = dev->num_queues * vduse_vq_log_size(VIRTQUEUE_MAX_SIZE);
void *log;
int i;
dev->log = log = vduse_log_get(filename, log_size);
if (log == MAP_FAILED) {
fprintf(stderr, "Failed to get vduse log\n");
return -EINVAL;
}
for (i = 0; i < dev->num_queues; i++) {
dev->vqs[i].log = log;
dev->vqs[i].log->inflight.desc_num = VIRTQUEUE_MAX_SIZE;
log = (void *)((char *)log + vduse_vq_log_size(VIRTQUEUE_MAX_SIZE));
}
return 0;
}
static int vduse_dev_init_vqs(VduseDev *dev, uint16_t num_queues)
{
VduseVirtq *vqs;
int i;
vqs = calloc(sizeof(VduseVirtq), num_queues);
if (!vqs) {
return -ENOMEM;
}
for (i = 0; i < num_queues; i++) {
vqs[i].index = i;
vqs[i].dev = dev;
vqs[i].fd = -1;
}
dev->vqs = vqs;
return 0;
}
static int vduse_dev_init(VduseDev *dev, const char *name,
uint16_t num_queues, const VduseOps *ops,
void *priv)
{
char *dev_path, *dev_name;
int ret, fd;
dev_path = malloc(strlen(name) + strlen("/dev/vduse/") + 1);
if (!dev_path) {
return -ENOMEM;
}
sprintf(dev_path, "/dev/vduse/%s", name);
fd = open(dev_path, O_RDWR);
free(dev_path);
if (fd < 0) {
fprintf(stderr, "Failed to open vduse dev %s: %s\n",
name, strerror(errno));
return -errno;
}
if (ioctl(fd, VDUSE_DEV_GET_FEATURES, &dev->features)) {
fprintf(stderr, "Failed to get features: %s\n", strerror(errno));
close(fd);
return -errno;
}
dev_name = strdup(name);
if (!dev_name) {
close(fd);
return -ENOMEM;
}
ret = vduse_dev_init_vqs(dev, num_queues);
if (ret) {
free(dev_name);
close(fd);
return ret;
}
dev->name = dev_name;
dev->num_queues = num_queues;
dev->fd = fd;
dev->ops = ops;
dev->priv = priv;
return 0;
}
static inline bool vduse_name_is_invalid(const char *name)
{
return strlen(name) >= VDUSE_NAME_MAX || strstr(name, "..");
}
VduseDev *vduse_dev_create_by_fd(int fd, uint16_t num_queues,
const VduseOps *ops, void *priv)
{
VduseDev *dev;
int ret;
if (!ops || !ops->enable_queue || !ops->disable_queue) {
fprintf(stderr, "Invalid parameter for vduse\n");
return NULL;
}
dev = calloc(sizeof(VduseDev), 1);
if (!dev) {
fprintf(stderr, "Failed to allocate vduse device\n");
return NULL;
}
if (ioctl(fd, VDUSE_DEV_GET_FEATURES, &dev->features)) {
fprintf(stderr, "Failed to get features: %s\n", strerror(errno));
free(dev);
return NULL;
}
ret = vduse_dev_init_vqs(dev, num_queues);
if (ret) {
fprintf(stderr, "Failed to init vqs\n");
free(dev);
return NULL;
}
dev->num_queues = num_queues;
dev->fd = fd;
dev->ops = ops;
dev->priv = priv;
return dev;
}
VduseDev *vduse_dev_create_by_name(const char *name, uint16_t num_queues,
const VduseOps *ops, void *priv)
{
VduseDev *dev;
int ret;
if (!name || vduse_name_is_invalid(name) || !ops ||
!ops->enable_queue || !ops->disable_queue) {
fprintf(stderr, "Invalid parameter for vduse\n");
return NULL;
}
dev = calloc(sizeof(VduseDev), 1);
if (!dev) {
fprintf(stderr, "Failed to allocate vduse device\n");
return NULL;
}
ret = vduse_dev_init(dev, name, num_queues, ops, priv);
if (ret < 0) {
fprintf(stderr, "Failed to init vduse device %s: %s\n",
name, strerror(-ret));
free(dev);
return NULL;
}
return dev;
}
VduseDev *vduse_dev_create(const char *name, uint32_t device_id,
uint32_t vendor_id, uint64_t features,
uint16_t num_queues, uint32_t config_size,
char *config, const VduseOps *ops, void *priv)
{
VduseDev *dev;
int ret, ctrl_fd;
uint64_t version;
struct vduse_dev_config *dev_config;
size_t size = offsetof(struct vduse_dev_config, config);
if (!name || vduse_name_is_invalid(name) ||
!has_feature(features, VIRTIO_F_VERSION_1) || !config ||
!config_size || !ops || !ops->enable_queue || !ops->disable_queue) {
fprintf(stderr, "Invalid parameter for vduse\n");
return NULL;
}
dev = calloc(sizeof(VduseDev), 1);
if (!dev) {
fprintf(stderr, "Failed to allocate vduse device\n");
return NULL;
}
ctrl_fd = open("/dev/vduse/control", O_RDWR);
if (ctrl_fd < 0) {
fprintf(stderr, "Failed to open /dev/vduse/control: %s\n",
strerror(errno));
goto err_ctrl;
}
version = VDUSE_API_VERSION;
if (ioctl(ctrl_fd, VDUSE_SET_API_VERSION, &version)) {
fprintf(stderr, "Failed to set api version %" PRIu64 ": %s\n",
version, strerror(errno));
goto err_dev;
}
dev_config = calloc(size + config_size, 1);
if (!dev_config) {
fprintf(stderr, "Failed to allocate config space\n");
goto err_dev;
}
assert(!vduse_name_is_invalid(name));
strcpy(dev_config->name, name);
dev_config->device_id = device_id;
dev_config->vendor_id = vendor_id;
dev_config->features = features;
dev_config->vq_num = num_queues;
dev_config->vq_align = VDUSE_VQ_ALIGN;
dev_config->config_size = config_size;
memcpy(dev_config->config, config, config_size);
ret = ioctl(ctrl_fd, VDUSE_CREATE_DEV, dev_config);
free(dev_config);
if (ret && errno != EEXIST) {
fprintf(stderr, "Failed to create vduse device %s: %s\n",
name, strerror(errno));
goto err_dev;
}
dev->ctrl_fd = ctrl_fd;
ret = vduse_dev_init(dev, name, num_queues, ops, priv);
if (ret < 0) {
fprintf(stderr, "Failed to init vduse device %s: %s\n",
name, strerror(-ret));
goto err;
}
return dev;
err:
ioctl(ctrl_fd, VDUSE_DESTROY_DEV, name);
err_dev:
close(ctrl_fd);
err_ctrl:
free(dev);
return NULL;
}
int vduse_dev_destroy(VduseDev *dev)
{
size_t log_size = dev->num_queues * vduse_vq_log_size(VIRTQUEUE_MAX_SIZE);
int i, ret = 0;
if (dev->log) {
munmap(dev->log, log_size);
}
for (i = 0; i < dev->num_queues; i++) {
free(dev->vqs[i].resubmit_list);
}
free(dev->vqs);
if (dev->fd >= 0) {
close(dev->fd);
dev->fd = -1;
}
if (dev->ctrl_fd >= 0) {
if (ioctl(dev->ctrl_fd, VDUSE_DESTROY_DEV, dev->name)) {
ret = -errno;
}
close(dev->ctrl_fd);
dev->ctrl_fd = -1;
}
free(dev->name);
free(dev);
return ret;
}