Add vhost-user as a vhost backend.
The initialization takes a chardev backed by a unix domain socket. It should implement qemu_fe_set_msgfds in order to be able to pass file descriptors to the remote process. Each ioctl request of vhost-kernel has a vhost-user message equivalent, which is sent over the control socket. The general approach is to copy the data from the supplied argument pointer to a designated field in the message. If a file descriptor is to be passed it will be placed in the fds array for inclusion in the sendmsg control header. VHOST_SET_MEM_TABLE ignores the supplied vhost_memory structure and scans the global ram_list for ram blocks with a valid fd field set. This would be set when the '-object memory-file' option with share=on property is used. Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com> Signed-off-by: Nikolay Nikolaev <n.nikolaev@virtualopensystems.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Nikolay Nikolaev
Michael S. Tsirkin
parent
1a1bfac9ee
commit
5f6f6664bf
@ -5,4 +5,4 @@ common-obj-y += virtio-mmio.o
|
||||
common-obj-$(CONFIG_VIRTIO_BLK_DATA_PLANE) += dataplane/
|
||||
|
||||
obj-y += virtio.o virtio-balloon.o
|
||||
obj-$(CONFIG_LINUX) += vhost.o vhost-backend.o
|
||||
obj-$(CONFIG_LINUX) += vhost.o vhost-backend.o vhost-user.o
|
||||
|
||||
@ -14,6 +14,8 @@
|
||||
|
||||
#include <sys/ioctl.h>
|
||||
|
||||
extern const VhostOps user_ops;
|
||||
|
||||
static int vhost_kernel_call(struct vhost_dev *dev, unsigned long int request,
|
||||
void *arg)
|
||||
{
|
||||
@ -57,6 +59,9 @@ int vhost_set_backend_type(struct vhost_dev *dev, VhostBackendType backend_type)
|
||||
case VHOST_BACKEND_TYPE_KERNEL:
|
||||
dev->vhost_ops = &kernel_ops;
|
||||
break;
|
||||
case VHOST_BACKEND_TYPE_USER:
|
||||
dev->vhost_ops = &user_ops;
|
||||
break;
|
||||
default:
|
||||
error_report("Unknown vhost backend type\n");
|
||||
r = -1;
|
||||
|
||||
342
hw/virtio/vhost-user.c
Normal file
342
hw/virtio/vhost-user.c
Normal file
@ -0,0 +1,342 @@
|
||||
/*
|
||||
* vhost-user
|
||||
*
|
||||
* Copyright (c) 2013 Virtual Open Systems Sarl.
|
||||
*
|
||||
* 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 "hw/virtio/vhost.h"
|
||||
#include "hw/virtio/vhost-backend.h"
|
||||
#include "sysemu/char.h"
|
||||
#include "sysemu/kvm.h"
|
||||
#include "qemu/error-report.h"
|
||||
#include "qemu/sockets.h"
|
||||
|
||||
#include <fcntl.h>
|
||||
#include <unistd.h>
|
||||
#include <sys/ioctl.h>
|
||||
#include <sys/socket.h>
|
||||
#include <sys/un.h>
|
||||
#include <linux/vhost.h>
|
||||
|
||||
#define VHOST_MEMORY_MAX_NREGIONS 8
|
||||
|
||||
typedef enum VhostUserRequest {
|
||||
VHOST_USER_NONE = 0,
|
||||
VHOST_USER_GET_FEATURES = 1,
|
||||
VHOST_USER_SET_FEATURES = 2,
|
||||
VHOST_USER_SET_OWNER = 3,
|
||||
VHOST_USER_RESET_OWNER = 4,
|
||||
VHOST_USER_SET_MEM_TABLE = 5,
|
||||
VHOST_USER_SET_LOG_BASE = 6,
|
||||
VHOST_USER_SET_LOG_FD = 7,
|
||||
VHOST_USER_SET_VRING_NUM = 8,
|
||||
VHOST_USER_SET_VRING_ADDR = 9,
|
||||
VHOST_USER_SET_VRING_BASE = 10,
|
||||
VHOST_USER_GET_VRING_BASE = 11,
|
||||
VHOST_USER_SET_VRING_KICK = 12,
|
||||
VHOST_USER_SET_VRING_CALL = 13,
|
||||
VHOST_USER_SET_VRING_ERR = 14,
|
||||
VHOST_USER_MAX
|
||||
} VhostUserRequest;
|
||||
|
||||
typedef struct VhostUserMemoryRegion {
|
||||
uint64_t guest_phys_addr;
|
||||
uint64_t memory_size;
|
||||
uint64_t userspace_addr;
|
||||
} VhostUserMemoryRegion;
|
||||
|
||||
typedef struct VhostUserMemory {
|
||||
uint32_t nregions;
|
||||
uint32_t padding;
|
||||
VhostUserMemoryRegion regions[VHOST_MEMORY_MAX_NREGIONS];
|
||||
} VhostUserMemory;
|
||||
|
||||
typedef struct VhostUserMsg {
|
||||
VhostUserRequest request;
|
||||
|
||||
#define VHOST_USER_VERSION_MASK (0x3)
|
||||
#define VHOST_USER_REPLY_MASK (0x1<<2)
|
||||
uint32_t flags;
|
||||
uint32_t size; /* the following payload size */
|
||||
union {
|
||||
#define VHOST_USER_VRING_IDX_MASK (0xff)
|
||||
#define VHOST_USER_VRING_NOFD_MASK (0x1<<8)
|
||||
uint64_t u64;
|
||||
struct vhost_vring_state state;
|
||||
struct vhost_vring_addr addr;
|
||||
VhostUserMemory memory;
|
||||
};
|
||||
} QEMU_PACKED VhostUserMsg;
|
||||
|
||||
static VhostUserMsg m __attribute__ ((unused));
|
||||
#define VHOST_USER_HDR_SIZE (sizeof(m.request) \
|
||||
+ sizeof(m.flags) \
|
||||
+ sizeof(m.size))
|
||||
|
||||
#define VHOST_USER_PAYLOAD_SIZE (sizeof(m) - VHOST_USER_HDR_SIZE)
|
||||
|
||||
/* The version of the protocol we support */
|
||||
#define VHOST_USER_VERSION (0x1)
|
||||
|
||||
static bool ioeventfd_enabled(void)
|
||||
{
|
||||
return kvm_enabled() && kvm_eventfds_enabled();
|
||||
}
|
||||
|
||||
static unsigned long int ioctl_to_vhost_user_request[VHOST_USER_MAX] = {
|
||||
-1, /* VHOST_USER_NONE */
|
||||
VHOST_GET_FEATURES, /* VHOST_USER_GET_FEATURES */
|
||||
VHOST_SET_FEATURES, /* VHOST_USER_SET_FEATURES */
|
||||
VHOST_SET_OWNER, /* VHOST_USER_SET_OWNER */
|
||||
VHOST_RESET_OWNER, /* VHOST_USER_RESET_OWNER */
|
||||
VHOST_SET_MEM_TABLE, /* VHOST_USER_SET_MEM_TABLE */
|
||||
VHOST_SET_LOG_BASE, /* VHOST_USER_SET_LOG_BASE */
|
||||
VHOST_SET_LOG_FD, /* VHOST_USER_SET_LOG_FD */
|
||||
VHOST_SET_VRING_NUM, /* VHOST_USER_SET_VRING_NUM */
|
||||
VHOST_SET_VRING_ADDR, /* VHOST_USER_SET_VRING_ADDR */
|
||||
VHOST_SET_VRING_BASE, /* VHOST_USER_SET_VRING_BASE */
|
||||
VHOST_GET_VRING_BASE, /* VHOST_USER_GET_VRING_BASE */
|
||||
VHOST_SET_VRING_KICK, /* VHOST_USER_SET_VRING_KICK */
|
||||
VHOST_SET_VRING_CALL, /* VHOST_USER_SET_VRING_CALL */
|
||||
VHOST_SET_VRING_ERR /* VHOST_USER_SET_VRING_ERR */
|
||||
};
|
||||
|
||||
static VhostUserRequest vhost_user_request_translate(unsigned long int request)
|
||||
{
|
||||
VhostUserRequest idx;
|
||||
|
||||
for (idx = 0; idx < VHOST_USER_MAX; idx++) {
|
||||
if (ioctl_to_vhost_user_request[idx] == request) {
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
return (idx == VHOST_USER_MAX) ? VHOST_USER_NONE : idx;
|
||||
}
|
||||
|
||||
static int vhost_user_read(struct vhost_dev *dev, VhostUserMsg *msg)
|
||||
{
|
||||
CharDriverState *chr = dev->opaque;
|
||||
uint8_t *p = (uint8_t *) msg;
|
||||
int r, size = VHOST_USER_HDR_SIZE;
|
||||
|
||||
r = qemu_chr_fe_read_all(chr, p, size);
|
||||
if (r != size) {
|
||||
error_report("Failed to read msg header. Read %d instead of %d.\n", r,
|
||||
size);
|
||||
goto fail;
|
||||
}
|
||||
|
||||
/* validate received flags */
|
||||
if (msg->flags != (VHOST_USER_REPLY_MASK | VHOST_USER_VERSION)) {
|
||||
error_report("Failed to read msg header."
|
||||
" Flags 0x%x instead of 0x%x.\n", msg->flags,
|
||||
VHOST_USER_REPLY_MASK | VHOST_USER_VERSION);
|
||||
goto fail;
|
||||
}
|
||||
|
||||
/* validate message size is sane */
|
||||
if (msg->size > VHOST_USER_PAYLOAD_SIZE) {
|
||||
error_report("Failed to read msg header."
|
||||
" Size %d exceeds the maximum %zu.\n", msg->size,
|
||||
VHOST_USER_PAYLOAD_SIZE);
|
||||
goto fail;
|
||||
}
|
||||
|
||||
if (msg->size) {
|
||||
p += VHOST_USER_HDR_SIZE;
|
||||
size = msg->size;
|
||||
r = qemu_chr_fe_read_all(chr, p, size);
|
||||
if (r != size) {
|
||||
error_report("Failed to read msg payload."
|
||||
" Read %d instead of %d.\n", r, msg->size);
|
||||
goto fail;
|
||||
}
|
||||
}
|
||||
|
||||
return 0;
|
||||
|
||||
fail:
|
||||
return -1;
|
||||
}
|
||||
|
||||
static int vhost_user_write(struct vhost_dev *dev, VhostUserMsg *msg,
|
||||
int *fds, int fd_num)
|
||||
{
|
||||
CharDriverState *chr = dev->opaque;
|
||||
int size = VHOST_USER_HDR_SIZE + msg->size;
|
||||
|
||||
if (fd_num) {
|
||||
qemu_chr_fe_set_msgfds(chr, fds, fd_num);
|
||||
}
|
||||
|
||||
return qemu_chr_fe_write_all(chr, (const uint8_t *) msg, size) == size ?
|
||||
0 : -1;
|
||||
}
|
||||
|
||||
static int vhost_user_call(struct vhost_dev *dev, unsigned long int request,
|
||||
void *arg)
|
||||
{
|
||||
VhostUserMsg msg;
|
||||
VhostUserRequest msg_request;
|
||||
RAMBlock *block = 0;
|
||||
struct vhost_vring_file *file = 0;
|
||||
int need_reply = 0;
|
||||
int fds[VHOST_MEMORY_MAX_NREGIONS];
|
||||
size_t fd_num = 0;
|
||||
|
||||
assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER);
|
||||
|
||||
msg_request = vhost_user_request_translate(request);
|
||||
msg.request = msg_request;
|
||||
msg.flags = VHOST_USER_VERSION;
|
||||
msg.size = 0;
|
||||
|
||||
switch (request) {
|
||||
case VHOST_GET_FEATURES:
|
||||
need_reply = 1;
|
||||
break;
|
||||
|
||||
case VHOST_SET_FEATURES:
|
||||
case VHOST_SET_LOG_BASE:
|
||||
msg.u64 = *((__u64 *) arg);
|
||||
msg.size = sizeof(m.u64);
|
||||
break;
|
||||
|
||||
case VHOST_SET_OWNER:
|
||||
case VHOST_RESET_OWNER:
|
||||
break;
|
||||
|
||||
case VHOST_SET_MEM_TABLE:
|
||||
QTAILQ_FOREACH(block, &ram_list.blocks, next)
|
||||
{
|
||||
if (block->fd > 0) {
|
||||
msg.memory.regions[fd_num].userspace_addr =
|
||||
(uintptr_t) block->host;
|
||||
msg.memory.regions[fd_num].memory_size = block->length;
|
||||
msg.memory.regions[fd_num].guest_phys_addr = block->offset;
|
||||
fds[fd_num++] = block->fd;
|
||||
}
|
||||
}
|
||||
|
||||
msg.memory.nregions = fd_num;
|
||||
|
||||
if (!fd_num) {
|
||||
error_report("Failed initializing vhost-user memory map\n"
|
||||
"consider using -object memory-backend-file share=on\n");
|
||||
return -1;
|
||||
}
|
||||
|
||||
msg.size = sizeof(m.memory.nregions);
|
||||
msg.size += sizeof(m.memory.padding);
|
||||
msg.size += fd_num * sizeof(VhostUserMemoryRegion);
|
||||
|
||||
break;
|
||||
|
||||
case VHOST_SET_LOG_FD:
|
||||
fds[fd_num++] = *((int *) arg);
|
||||
break;
|
||||
|
||||
case VHOST_SET_VRING_NUM:
|
||||
case VHOST_SET_VRING_BASE:
|
||||
memcpy(&msg.state, arg, sizeof(struct vhost_vring_state));
|
||||
msg.size = sizeof(m.state);
|
||||
break;
|
||||
|
||||
case VHOST_GET_VRING_BASE:
|
||||
memcpy(&msg.state, arg, sizeof(struct vhost_vring_state));
|
||||
msg.size = sizeof(m.state);
|
||||
need_reply = 1;
|
||||
break;
|
||||
|
||||
case VHOST_SET_VRING_ADDR:
|
||||
memcpy(&msg.addr, arg, sizeof(struct vhost_vring_addr));
|
||||
msg.size = sizeof(m.addr);
|
||||
break;
|
||||
|
||||
case VHOST_SET_VRING_KICK:
|
||||
case VHOST_SET_VRING_CALL:
|
||||
case VHOST_SET_VRING_ERR:
|
||||
file = arg;
|
||||
msg.u64 = file->index & VHOST_USER_VRING_IDX_MASK;
|
||||
msg.size = sizeof(m.u64);
|
||||
if (ioeventfd_enabled() && file->fd > 0) {
|
||||
fds[fd_num++] = file->fd;
|
||||
} else {
|
||||
msg.u64 |= VHOST_USER_VRING_NOFD_MASK;
|
||||
}
|
||||
break;
|
||||
default:
|
||||
error_report("vhost-user trying to send unhandled ioctl\n");
|
||||
return -1;
|
||||
break;
|
||||
}
|
||||
|
||||
if (vhost_user_write(dev, &msg, fds, fd_num) < 0) {
|
||||
return 0;
|
||||
}
|
||||
|
||||
if (need_reply) {
|
||||
if (vhost_user_read(dev, &msg) < 0) {
|
||||
return 0;
|
||||
}
|
||||
|
||||
if (msg_request != msg.request) {
|
||||
error_report("Received unexpected msg type."
|
||||
" Expected %d received %d\n", msg_request, msg.request);
|
||||
return -1;
|
||||
}
|
||||
|
||||
switch (msg_request) {
|
||||
case VHOST_USER_GET_FEATURES:
|
||||
if (msg.size != sizeof(m.u64)) {
|
||||
error_report("Received bad msg size.\n");
|
||||
return -1;
|
||||
}
|
||||
*((__u64 *) arg) = msg.u64;
|
||||
break;
|
||||
case VHOST_USER_GET_VRING_BASE:
|
||||
if (msg.size != sizeof(m.state)) {
|
||||
error_report("Received bad msg size.\n");
|
||||
return -1;
|
||||
}
|
||||
memcpy(arg, &msg.state, sizeof(struct vhost_vring_state));
|
||||
break;
|
||||
default:
|
||||
error_report("Received unexpected msg type.\n");
|
||||
return -1;
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int vhost_user_init(struct vhost_dev *dev, void *opaque)
|
||||
{
|
||||
assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER);
|
||||
|
||||
dev->opaque = opaque;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int vhost_user_cleanup(struct vhost_dev *dev)
|
||||
{
|
||||
assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER);
|
||||
|
||||
dev->opaque = 0;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
const VhostOps user_ops = {
|
||||
.backend_type = VHOST_BACKEND_TYPE_USER,
|
||||
.vhost_call = vhost_user_call,
|
||||
.vhost_backend_init = vhost_user_init,
|
||||
.vhost_backend_cleanup = vhost_user_cleanup
|
||||
};
|
||||
Loading…
Reference in New Issue
Block a user