blob: 78eaa64bda17b5ce4bc58fa243c21b4276b1d929 [file] [log] [blame]
#include "kvm/virtio-rng.h"
#include "kvm/virtio-pci-dev.h"
#include "kvm/virtio.h"
#include "kvm/util.h"
#include "kvm/kvm.h"
#include "kvm/threadpool.h"
#include "kvm/guest_compat.h"
#include <linux/virtio_ring.h>
#include <linux/virtio_rng.h>
#include <linux/list.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <pthread.h>
#include <linux/kernel.h>
#define NUM_VIRT_QUEUES 1
#define VIRTIO_RNG_QUEUE_SIZE 128
struct rng_dev_job {
struct virt_queue *vq;
struct rng_dev *rdev;
struct thread_pool__job job_id;
};
struct rng_dev {
struct list_head list;
struct virtio_device vdev;
int fd;
/* virtio queue */
struct virt_queue vqs[NUM_VIRT_QUEUES];
struct rng_dev_job jobs[NUM_VIRT_QUEUES];
};
static LIST_HEAD(rdevs);
static int compat_id = -1;
static u8 *get_config(struct kvm *kvm, void *dev)
{
/* Unused */
return 0;
}
static u32 get_host_features(struct kvm *kvm, void *dev)
{
/* Unused */
return 0;
}
static void set_guest_features(struct kvm *kvm, void *dev, u32 features)
{
/* Unused */
}
static bool virtio_rng_do_io_request(struct kvm *kvm, struct rng_dev *rdev, struct virt_queue *queue)
{
struct iovec iov[VIRTIO_RNG_QUEUE_SIZE];
ssize_t len = 0;
u16 out, in, head;
head = virt_queue__get_iov(queue, iov, &out, &in, kvm);
len = readv(rdev->fd, iov, in);
if (len < 0 && errno == EAGAIN)
len = 0;
virt_queue__set_used_elem(queue, head, len);
return true;
}
static void virtio_rng_do_io(struct kvm *kvm, void *param)
{
struct rng_dev_job *job = param;
struct virt_queue *vq = job->vq;
struct rng_dev *rdev = job->rdev;
while (virt_queue__available(vq))
virtio_rng_do_io_request(kvm, rdev, vq);
rdev->vdev.ops->signal_vq(kvm, &rdev->vdev, vq - rdev->vqs);
}
static int init_vq(struct kvm *kvm, void *dev, u32 vq, u32 page_size, u32 align,
u32 pfn)
{
struct rng_dev *rdev = dev;
struct virt_queue *queue;
struct rng_dev_job *job;
void *p;
compat__remove_message(compat_id);
queue = &rdev->vqs[vq];
queue->pfn = pfn;
p = virtio_get_vq(kvm, queue->pfn, page_size);
job = &rdev->jobs[vq];
vring_init(&queue->vring, VIRTIO_RNG_QUEUE_SIZE, p, align);
virtio_init_device_vq(&rdev->vdev, queue);
*job = (struct rng_dev_job) {
.vq = queue,
.rdev = rdev,
};
thread_pool__init_job(&job->job_id, kvm, virtio_rng_do_io, job);
return 0;
}
static int notify_vq(struct kvm *kvm, void *dev, u32 vq)
{
struct rng_dev *rdev = dev;
thread_pool__do_job(&rdev->jobs[vq].job_id);
return 0;
}
static struct virt_queue *get_vq(struct kvm *kvm, void *dev, u32 vq)
{
struct rng_dev *rdev = dev;
return &rdev->vqs[vq];
}
static int get_size_vq(struct kvm *kvm, void *dev, u32 vq)
{
return VIRTIO_RNG_QUEUE_SIZE;
}
static int set_size_vq(struct kvm *kvm, void *dev, u32 vq, int size)
{
/* FIXME: dynamic */
return size;
}
static int get_vq_count(struct kvm *kvm, void *dev)
{
return NUM_VIRT_QUEUES;
}
static struct virtio_ops rng_dev_virtio_ops = {
.get_config = get_config,
.get_host_features = get_host_features,
.set_guest_features = set_guest_features,
.init_vq = init_vq,
.notify_vq = notify_vq,
.get_vq = get_vq,
.get_size_vq = get_size_vq,
.set_size_vq = set_size_vq,
.get_vq_count = get_vq_count,
};
int virtio_rng__init(struct kvm *kvm)
{
struct rng_dev *rdev;
int r;
if (!kvm->cfg.virtio_rng)
return 0;
rdev = malloc(sizeof(*rdev));
if (rdev == NULL)
return -ENOMEM;
rdev->fd = open("/dev/random", O_RDONLY | O_NONBLOCK);
if (rdev->fd < 0) {
r = rdev->fd;
goto cleanup;
}
r = virtio_init(kvm, rdev, &rdev->vdev, &rng_dev_virtio_ops,
VIRTIO_DEFAULT_TRANS(kvm), PCI_DEVICE_ID_VIRTIO_RNG,
VIRTIO_ID_RNG, PCI_CLASS_RNG);
if (r < 0)
goto cleanup;
list_add_tail(&rdev->list, &rdevs);
if (compat_id == -1)
compat_id = virtio_compat_add_message("virtio-rng", "CONFIG_HW_RANDOM_VIRTIO");
return 0;
cleanup:
close(rdev->fd);
free(rdev);
return r;
}
virtio_dev_init(virtio_rng__init);
int virtio_rng__exit(struct kvm *kvm)
{
struct rng_dev *rdev, *tmp;
list_for_each_entry_safe(rdev, tmp, &rdevs, list) {
list_del(&rdev->list);
rdev->vdev.ops->exit(kvm, &rdev->vdev);
free(rdev);
}
return 0;
}
virtio_dev_exit(virtio_rng__exit);