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/*
* Copyright (c) 2022, Nutanix Inc. All rights reserved.
* Author: Thanos Makatos <thanos@nutanix.com>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of Nutanix nor the names of its contributors may be
* used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
*/
/*
* shadow_ioeventfd_server.c: an example of how to use a shadow ioeventfd.
* There is no Linux kernel driver, use samples/shadow_ioeventfd_speed_test.c
* in the guest instead.
*/
#include <stdio.h>
#include <err.h>
#include <stdlib.h>
#include <errno.h>
#include <assert.h>
#include <sys/poll.h>
#include <sys/eventfd.h>
#include <sys/mman.h>
#include <sys/syscall.h>
#include "libvfio-user.h"
#include "common.h"
static void
_log(vfu_ctx_t *vfu_ctx UNUSED, int level UNUSED, char const *msg)
{
fprintf(stderr, "%s\n", msg);
}
static ssize_t
bar0_cb(vfu_ctx_t *vfu_ctx UNUSED, char * const buf UNUSED,
size_t count UNUSED, loff_t offset UNUSED,
const bool is_write UNUSED)
{
return count;
}
int
main(int argc, char *argv[])
{
int ret;
vfu_ctx_t *vfu_ctx;
struct pollfd fds[2]; /* one for vfu_ctx, one for shadow_ioeventfd */
int fd, bar0_fd;
if (argc != 2) {
errx(EXIT_FAILURE, "missing vfio-user socket path");
}
vfu_ctx = vfu_create_ctx(VFU_TRANS_SOCK, argv[1],
LIBVFIO_USER_FLAG_ATTACH_NB, NULL,
VFU_DEV_TYPE_PCI);
if (vfu_ctx == NULL) {
err(EXIT_FAILURE, "failed to initialize device emulation");
}
ret = vfu_setup_log(vfu_ctx, _log, LOG_ERR);
if (ret < 0) {
err(EXIT_FAILURE, "failed to setup log");
}
ret = vfu_pci_init(vfu_ctx, VFU_PCI_TYPE_CONVENTIONAL,
PCI_HEADER_TYPE_NORMAL, 0);
if (ret < 0) {
err(EXIT_FAILURE, "vfu_pci_init() failed");
}
vfu_pci_set_id(vfu_ctx, 0x4e58, 0, 0x0, 0x0);
ret = vfu_setup_region(vfu_ctx, VFU_PCI_DEV_BAR0_REGION_IDX,
sysconf(_SC_PAGE_SIZE), &bar0_cb,
VFU_REGION_FLAG_RW | VFU_REGION_FLAG_MEM, NULL, 0,
-1, 0);
if (ret < 0) {
err(EXIT_FAILURE, "failed to setup region");
}
ret = vfu_realize_ctx(vfu_ctx);
if (ret < 0) {
err(EXIT_FAILURE, "failed to realize device");
}
fds[0] = (struct pollfd) {
.fd = vfu_get_poll_fd(vfu_ctx),
.events = POLLIN | POLLOUT
};
ret = poll(fds, 1, -1);
assert(ret == 1);
ret = vfu_attach_ctx(vfu_ctx);
if (ret < 0) {
err(EXIT_FAILURE, "failed to attach device");
}
fd = eventfd(0, 0);
if (fd == -1) {
err(EXIT_FAILURE, "failed to create eventfd");
}
bar0_fd = syscall(SYS_memfd_create, "BAR0", 0);
if (bar0_fd == -1) {
err(EXIT_FAILURE, "failed to create BAR0 file");
}
ret = ftruncate(bar0_fd, sysconf(_SC_PAGESIZE));
if (ret == -1) {
err(EXIT_FAILURE, "failed to truncate BAR0 file");
}
ret = vfu_create_ioeventfd(vfu_ctx, VFU_PCI_DEV_BAR0_REGION_IDX,
fd, 0, 4,
0, false, bar0_fd, 0);
if (ret == -1) {
err(EXIT_FAILURE, "failed to create shadow ioeventfd");
}
fds[0] = (struct pollfd) {
.fd = vfu_get_poll_fd(vfu_ctx),
.events = POLLIN
};
fds[1] = (struct pollfd) {
.fd = fd,
.events = POLLIN
};
do {
ret = poll(fds, 2, -1);
if (ret < 0) {
err(EXIT_FAILURE, "failed to poll(2)");
}
assert(ret > 0);
if (fds[0].revents & (POLLIN)) {
ret = vfu_run_ctx(vfu_ctx);
if (ret < 0) {
if (errno == EAGAIN) {
continue;
}
if (errno == ENOTCONN) {
return 0;
}
err(EXIT_FAILURE, "vfu_run_ctx() failed");
}
}
if (fds[1].revents & POLLIN) {
eventfd_t value;
eventfd_read(fd, &value);
bar0_cb(vfu_ctx, NULL, 4, 0, true);
}
} while (true);
return 0;
}
/* ex: set tabstop=4 shiftwidth=4 softtabstop=4 expandtab: */
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