tools/virtio: virtio_test tool

This is the userspace part of the tool: it includes a bunch of stubs for
linux APIs, somewhat simular to linuxsched. This makes it possible to
recompile the ring code in userspace.

A small test example is implemented combining this with vhost_test
module.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Michael S. Tsirkin 2010-11-29 19:16:37 +02:00
parent 71ccc212e5
commit 4e53f78e5b
5 changed files with 487 additions and 0 deletions

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tools/virtio/Makefile Normal file
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all: test mod
test: virtio_test
virtio_test: virtio_ring.o virtio_test.o
CFLAGS += -g -O2 -Wall -I. -I ../../usr/include/ -Wno-pointer-sign -fno-strict-overflow -MMD
vpath %.c ../../drivers/virtio
mod:
${MAKE} -C `pwd`/../.. M=`pwd`/vhost_test
.PHONY: all test mod clean
clean:
${RM} *.o vhost_test/*.o vhost_test/.*.cmd \
vhost_test/Module.symvers vhost_test/modules.order *.d
-include *.d

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#ifndef LINUX_DEVICE_H
#endif

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#ifndef LINUX_SLAB_H
#endif

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tools/virtio/linux/virtio.h Normal file
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#ifndef LINUX_VIRTIO_H
#define LINUX_VIRTIO_H
#include <stdbool.h>
#include <stdlib.h>
#include <stddef.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include <linux/types.h>
#include <errno.h>
typedef unsigned long long dma_addr_t;
struct scatterlist {
unsigned long page_link;
unsigned int offset;
unsigned int length;
dma_addr_t dma_address;
};
struct page {
unsigned long long dummy;
};
#define BUG_ON(__BUG_ON_cond) assert(!(__BUG_ON_cond))
/* Physical == Virtual */
#define virt_to_phys(p) ((unsigned long)p)
#define phys_to_virt(a) ((void *)(unsigned long)(a))
/* Page address: Virtual / 4K */
#define virt_to_page(p) ((struct page*)((virt_to_phys(p) / 4096) * \
sizeof(struct page)))
#define offset_in_page(p) (((unsigned long)p) % 4096)
#define sg_phys(sg) ((sg->page_link & ~0x3) / sizeof(struct page) * 4096 + \
sg->offset)
static inline void sg_mark_end(struct scatterlist *sg)
{
/*
* Set termination bit, clear potential chain bit
*/
sg->page_link |= 0x02;
sg->page_link &= ~0x01;
}
static inline void sg_init_table(struct scatterlist *sgl, unsigned int nents)
{
memset(sgl, 0, sizeof(*sgl) * nents);
sg_mark_end(&sgl[nents - 1]);
}
static inline void sg_assign_page(struct scatterlist *sg, struct page *page)
{
unsigned long page_link = sg->page_link & 0x3;
/*
* In order for the low bit stealing approach to work, pages
* must be aligned at a 32-bit boundary as a minimum.
*/
BUG_ON((unsigned long) page & 0x03);
sg->page_link = page_link | (unsigned long) page;
}
static inline void sg_set_page(struct scatterlist *sg, struct page *page,
unsigned int len, unsigned int offset)
{
sg_assign_page(sg, page);
sg->offset = offset;
sg->length = len;
}
static inline void sg_set_buf(struct scatterlist *sg, const void *buf,
unsigned int buflen)
{
sg_set_page(sg, virt_to_page(buf), buflen, offset_in_page(buf));
}
static inline void sg_init_one(struct scatterlist *sg, const void *buf, unsigned int buflen)
{
sg_init_table(sg, 1);
sg_set_buf(sg, buf, buflen);
}
typedef __u16 u16;
typedef enum {
GFP_KERNEL,
GFP_ATOMIC,
} gfp_t;
typedef enum {
IRQ_NONE,
IRQ_HANDLED
} irqreturn_t;
static inline void *kmalloc(size_t s, gfp_t gfp)
{
return malloc(s);
}
static inline void kfree(void *p)
{
free(p);
}
#define container_of(ptr, type, member) ({ \
const typeof( ((type *)0)->member ) *__mptr = (ptr); \
(type *)( (char *)__mptr - offsetof(type,member) );})
#define uninitialized_var(x) x = x
# ifndef likely
# define likely(x) (__builtin_expect(!!(x), 1))
# endif
# ifndef unlikely
# define unlikely(x) (__builtin_expect(!!(x), 0))
# endif
#define pr_err(format, ...) fprintf (stderr, format, ## __VA_ARGS__)
#ifdef DEBUG
#define pr_debug(format, ...) fprintf (stderr, format, ## __VA_ARGS__)
#else
#define pr_debug(format, ...) do {} while (0)
#endif
#define dev_err(dev, format, ...) fprintf (stderr, format, ## __VA_ARGS__)
#define dev_warn(dev, format, ...) fprintf (stderr, format, ## __VA_ARGS__)
/* TODO: empty stubs for now. Broken but enough for virtio_ring.c */
#define list_add_tail(a, b) do {} while (0)
#define list_del(a) do {} while (0)
#define BIT_WORD(nr) ((nr) / BITS_PER_LONG)
#define BITS_PER_BYTE 8
#define BITS_PER_LONG (sizeof(long) * BITS_PER_BYTE)
#define BIT_MASK(nr) (1UL << ((nr) % BITS_PER_LONG))
/* TODO: Not atomic as it should be:
* we don't use this for anything important. */
static inline void clear_bit(int nr, volatile unsigned long *addr)
{
unsigned long mask = BIT_MASK(nr);
unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
*p &= ~mask;
}
static inline int test_bit(int nr, const volatile unsigned long *addr)
{
return 1UL & (addr[BIT_WORD(nr)] >> (nr & (BITS_PER_LONG-1)));
}
/* The only feature we care to support */
#define virtio_has_feature(dev, feature) \
test_bit((feature), (dev)->features)
/* end of stubs */
struct virtio_device {
void *dev;
unsigned long features[1];
};
struct virtqueue {
/* TODO: commented as list macros are empty stubs for now.
* Broken but enough for virtio_ring.c
* struct list_head list; */
void (*callback)(struct virtqueue *vq);
const char *name;
struct virtio_device *vdev;
void *priv;
};
#define EXPORT_SYMBOL_GPL(__EXPORT_SYMBOL_GPL_name) \
void __EXPORT_SYMBOL_GPL##__EXPORT_SYMBOL_GPL_name() { \
}
#define MODULE_LICENSE(__MODULE_LICENSE_value) \
const char *__MODULE_LICENSE_name = __MODULE_LICENSE_value
#define CONFIG_SMP
#if defined(__i386__) || defined(__x86_64__)
#define barrier() asm volatile("" ::: "memory")
#define mb() __sync_synchronize()
#define smp_mb() mb()
# define smp_rmb() barrier()
# define smp_wmb() barrier()
#else
#error Please fill in barrier macros
#endif
/* Interfaces exported by virtio_ring. */
int virtqueue_add_buf_gfp(struct virtqueue *vq,
struct scatterlist sg[],
unsigned int out_num,
unsigned int in_num,
void *data,
gfp_t gfp);
static inline int virtqueue_add_buf(struct virtqueue *vq,
struct scatterlist sg[],
unsigned int out_num,
unsigned int in_num,
void *data)
{
return virtqueue_add_buf_gfp(vq, sg, out_num, in_num, data, GFP_ATOMIC);
}
void virtqueue_kick(struct virtqueue *vq);
void *virtqueue_get_buf(struct virtqueue *vq, unsigned int *len);
void virtqueue_disable_cb(struct virtqueue *vq);
bool virtqueue_enable_cb(struct virtqueue *vq);
void *virtqueue_detach_unused_buf(struct virtqueue *vq);
struct virtqueue *vring_new_virtqueue(unsigned int num,
unsigned int vring_align,
struct virtio_device *vdev,
void *pages,
void (*notify)(struct virtqueue *vq),
void (*callback)(struct virtqueue *vq),
const char *name);
void vring_del_virtqueue(struct virtqueue *vq);
#endif

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tools/virtio/virtio_test.c Normal file
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#define _GNU_SOURCE
#include <getopt.h>
#include <string.h>
#include <poll.h>
#include <sys/eventfd.h>
#include <stdlib.h>
#include <assert.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <fcntl.h>
#include <linux/vhost.h>
#include <linux/virtio.h>
#include <linux/virtio_ring.h>
#include "../../drivers/vhost/test.h"
struct vq_info {
int kick;
int call;
int num;
int idx;
void *ring;
/* copy used for control */
struct vring vring;
struct virtqueue *vq;
};
struct vdev_info {
struct virtio_device vdev;
int control;
struct pollfd fds[1];
struct vq_info vqs[1];
int nvqs;
void *buf;
size_t buf_size;
struct vhost_memory *mem;
};
void vq_notify(struct virtqueue *vq)
{
struct vq_info *info = vq->priv;
unsigned long long v = 1;
int r;
r = write(info->kick, &v, sizeof v);
assert(r == sizeof v);
}
void vq_callback(struct virtqueue *vq)
{
}
void vhost_vq_setup(struct vdev_info *dev, struct vq_info *info)
{
struct vhost_vring_state state = { .index = info->idx };
struct vhost_vring_file file = { .index = info->idx };
unsigned long long features = dev->vdev.features[0];
struct vhost_vring_addr addr = {
.index = info->idx,
.desc_user_addr = (uint64_t)(unsigned long)info->vring.desc,
.avail_user_addr = (uint64_t)(unsigned long)info->vring.avail,
.used_user_addr = (uint64_t)(unsigned long)info->vring.used,
};
int r;
r = ioctl(dev->control, VHOST_SET_FEATURES, &features);
assert(r >= 0);
state.num = info->vring.num;
r = ioctl(dev->control, VHOST_SET_VRING_NUM, &state);
assert(r >= 0);
state.num = 0;
r = ioctl(dev->control, VHOST_SET_VRING_BASE, &state);
assert(r >= 0);
r = ioctl(dev->control, VHOST_SET_VRING_ADDR, &addr);
assert(r >= 0);
file.fd = info->kick;
r = ioctl(dev->control, VHOST_SET_VRING_KICK, &file);
assert(r >= 0);
file.fd = info->call;
r = ioctl(dev->control, VHOST_SET_VRING_CALL, &file);
assert(r >= 0);
}
static void vq_info_add(struct vdev_info *dev, int num)
{
struct vq_info *info = &dev->vqs[dev->nvqs];
int r;
info->idx = dev->nvqs;
info->kick = eventfd(0, EFD_NONBLOCK);
info->call = eventfd(0, EFD_NONBLOCK);
r = posix_memalign(&info->ring, 4096, vring_size(num, 4096));
assert(r >= 0);
memset(info->ring, 0, vring_size(num, 4096));
vring_init(&info->vring, num, info->ring, 4096);
info->vq = vring_new_virtqueue(info->vring.num, 4096, &dev->vdev, info->ring,
vq_notify, vq_callback, "test");
assert(info->vq);
info->vq->priv = info;
vhost_vq_setup(dev, info);
dev->fds[info->idx].fd = info->call;
dev->fds[info->idx].events = POLLIN;
dev->nvqs++;
}
static void vdev_info_init(struct vdev_info* dev, unsigned long long features)
{
int r;
memset(dev, 0, sizeof *dev);
dev->vdev.features[0] = features;
dev->vdev.features[1] = features >> 32;
dev->buf_size = 1024;
dev->buf = malloc(dev->buf_size);
assert(dev->buf);
dev->control = open("/dev/vhost-test", O_RDWR);
assert(dev->control >= 0);
r = ioctl(dev->control, VHOST_SET_OWNER, NULL);
assert(r >= 0);
dev->mem = malloc(offsetof(struct vhost_memory, regions) +
sizeof dev->mem->regions[0]);
assert(dev->mem);
memset(dev->mem, 0, offsetof(struct vhost_memory, regions) +
sizeof dev->mem->regions[0]);
dev->mem->nregions = 1;
dev->mem->regions[0].guest_phys_addr = (long)dev->buf;
dev->mem->regions[0].userspace_addr = (long)dev->buf;
dev->mem->regions[0].memory_size = dev->buf_size;
r = ioctl(dev->control, VHOST_SET_MEM_TABLE, dev->mem);
assert(r >= 0);
}
/* TODO: this is pretty bad: we get a cache line bounce
* for the wait queue on poll and another one on read,
* plus the read which is there just to clear the
* current state. */
static void wait_for_interrupt(struct vdev_info *dev)
{
int i;
unsigned long long val;
poll(dev->fds, dev->nvqs, -1);
for (i = 0; i < dev->nvqs; ++i)
if (dev->fds[i].revents & POLLIN) {
read(dev->fds[i].fd, &val, sizeof val);
}
}
static void run_test(struct vdev_info *dev, struct vq_info *vq, int bufs)
{
struct scatterlist sl;
long started = 0, completed = 0;
long completed_before;
int r, test = 1;
unsigned len;
long long spurious = 0;
r = ioctl(dev->control, VHOST_TEST_RUN, &test);
assert(r >= 0);
for (;;) {
virtqueue_disable_cb(vq->vq);
completed_before = completed;
do {
if (started < bufs) {
sg_init_one(&sl, dev->buf, dev->buf_size);
r = virtqueue_add_buf(vq->vq, &sl, 1, 0,
dev->buf + started);
if (likely(r >= 0)) {
++started;
virtqueue_kick(vq->vq);
}
} else
r = -1;
/* Flush out completed bufs if any */
if (virtqueue_get_buf(vq->vq, &len)) {
++completed;
r = 0;
}
} while (r >= 0);
if (completed == completed_before)
++spurious;
assert(completed <= bufs);
assert(started <= bufs);
if (completed == bufs)
break;
if (virtqueue_enable_cb(vq->vq)) {
wait_for_interrupt(dev);
}
}
test = 0;
r = ioctl(dev->control, VHOST_TEST_RUN, &test);
assert(r >= 0);
fprintf(stderr, "spurious wakeus: 0x%llx\n", spurious);
}
const char optstring[] = "h";
const struct option longopts[] = {
{
.name = "help",
.val = 'h',
},
{
.name = "indirect",
.val = 'I',
},
{
.name = "no-indirect",
.val = 'i',
},
{
}
};
static void help()
{
fprintf(stderr, "Usage: virtio_test [--help] [--no-indirect]\n");
}
int main(int argc, char **argv)
{
struct vdev_info dev;
unsigned long long features = 1ULL << VIRTIO_RING_F_INDIRECT_DESC;
int o;
for (;;) {
o = getopt_long(argc, argv, optstring, longopts, NULL);
switch (o) {
case -1:
goto done;
case '?':
help();
exit(2);
case 'h':
help();
goto done;
case 'i':
features &= ~(1ULL << VIRTIO_RING_F_INDIRECT_DESC);
break;
default:
assert(0);
break;
}
}
done:
vdev_info_init(&dev, features);
vq_info_add(&dev, 256);
run_test(&dev, &dev.vqs[0], 0x100000);
return 0;
}