um: virtio: Implement VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS
Implement in-band notifications that are necessary for running vhost-user devices under externally synchronized time-travel mode (which is in a follow-up patch). This feature makes what usually should be eventfd notifications in-band messages. We'll prefer this feature, under the assumption that only a few (simulation) devices will ever support it, since it's not very efficient. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Richard Weinberger <richard@nod.at>
This commit is contained in:
Johannes Berg
Richard Weinberger
parent
4b786e24ca
commit
dd9ada5627
|
|
@ -10,9 +10,10 @@
|
|||
/* Feature bits */
|
||||
#define VHOST_USER_F_PROTOCOL_FEATURES 30
|
||||
/* Protocol feature bits */
|
||||
#define VHOST_USER_PROTOCOL_F_REPLY_ACK 3
|
||||
#define VHOST_USER_PROTOCOL_F_SLAVE_REQ 5
|
||||
#define VHOST_USER_PROTOCOL_F_CONFIG 9
|
||||
#define VHOST_USER_PROTOCOL_F_REPLY_ACK 3
|
||||
#define VHOST_USER_PROTOCOL_F_SLAVE_REQ 5
|
||||
#define VHOST_USER_PROTOCOL_F_CONFIG 9
|
||||
#define VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS 14
|
||||
/* Vring state index masks */
|
||||
#define VHOST_USER_VRING_INDEX_MASK 0xff
|
||||
#define VHOST_USER_VRING_POLL_MASK BIT(8)
|
||||
|
|
@ -24,7 +25,8 @@
|
|||
/* Supported protocol features */
|
||||
#define VHOST_USER_SUPPORTED_PROTOCOL_F (BIT_ULL(VHOST_USER_PROTOCOL_F_REPLY_ACK) | \
|
||||
BIT_ULL(VHOST_USER_PROTOCOL_F_SLAVE_REQ) | \
|
||||
BIT_ULL(VHOST_USER_PROTOCOL_F_CONFIG))
|
||||
BIT_ULL(VHOST_USER_PROTOCOL_F_CONFIG) | \
|
||||
BIT_ULL(VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS))
|
||||
|
||||
enum vhost_user_request {
|
||||
VHOST_USER_GET_FEATURES = 1,
|
||||
|
|
@ -52,12 +54,14 @@ enum vhost_user_request {
|
|||
VHOST_USER_SET_VRING_ENDIAN = 23,
|
||||
VHOST_USER_GET_CONFIG = 24,
|
||||
VHOST_USER_SET_CONFIG = 25,
|
||||
VHOST_USER_VRING_KICK = 35,
|
||||
};
|
||||
|
||||
enum vhost_user_slave_request {
|
||||
VHOST_USER_SLAVE_IOTLB_MSG = 1,
|
||||
VHOST_USER_SLAVE_CONFIG_CHANGE_MSG = 2,
|
||||
VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG = 3,
|
||||
VHOST_USER_SLAVE_VRING_CALL = 4,
|
||||
};
|
||||
|
||||
struct vhost_user_header {
|
||||
|
|
|
|||
|
|
@ -53,6 +53,7 @@ struct virtio_uml_device {
|
|||
struct virtio_device vdev;
|
||||
struct platform_device *pdev;
|
||||
|
||||
spinlock_t sock_lock;
|
||||
int sock, req_fd;
|
||||
u64 features;
|
||||
u64 protocol_features;
|
||||
|
|
@ -189,6 +190,7 @@ static int vhost_user_send(struct virtio_uml_device *vu_dev,
|
|||
int *fds, size_t num_fds)
|
||||
{
|
||||
size_t size = sizeof(msg->header) + msg->header.size;
|
||||
unsigned long flags;
|
||||
bool request_ack;
|
||||
int rc;
|
||||
|
||||
|
|
@ -207,24 +209,28 @@ static int vhost_user_send(struct virtio_uml_device *vu_dev,
|
|||
if (request_ack)
|
||||
msg->header.flags |= VHOST_USER_FLAG_NEED_REPLY;
|
||||
|
||||
spin_lock_irqsave(&vu_dev->sock_lock, flags);
|
||||
rc = full_sendmsg_fds(vu_dev->sock, msg, size, fds, num_fds);
|
||||
if (rc < 0)
|
||||
return rc;
|
||||
goto out;
|
||||
|
||||
if (request_ack) {
|
||||
uint64_t status;
|
||||
|
||||
rc = vhost_user_recv_u64(vu_dev, &status);
|
||||
if (rc)
|
||||
return rc;
|
||||
goto out;
|
||||
|
||||
if (status) {
|
||||
vu_err(vu_dev, "slave reports error: %llu\n", status);
|
||||
return -EIO;
|
||||
rc = -EIO;
|
||||
goto out;
|
||||
}
|
||||
}
|
||||
|
||||
return 0;
|
||||
out:
|
||||
spin_unlock_irqrestore(&vu_dev->sock_lock, flags);
|
||||
return rc;
|
||||
}
|
||||
|
||||
static int vhost_user_send_no_payload(struct virtio_uml_device *vu_dev,
|
||||
|
|
@ -324,6 +330,7 @@ static void vhost_user_reply(struct virtio_uml_device *vu_dev,
|
|||
static irqreturn_t vu_req_interrupt(int irq, void *data)
|
||||
{
|
||||
struct virtio_uml_device *vu_dev = data;
|
||||
struct virtqueue *vq;
|
||||
int response = 1;
|
||||
struct {
|
||||
struct vhost_user_msg msg;
|
||||
|
|
@ -343,6 +350,15 @@ static irqreturn_t vu_req_interrupt(int irq, void *data)
|
|||
virtio_config_changed(&vu_dev->vdev);
|
||||
response = 0;
|
||||
break;
|
||||
case VHOST_USER_SLAVE_VRING_CALL:
|
||||
virtio_device_for_each_vq((&vu_dev->vdev), vq) {
|
||||
if (vq->index == msg.msg.payload.vring_state.index) {
|
||||
response = 0;
|
||||
vring_interrupt(0 /* ignored */, vq);
|
||||
break;
|
||||
}
|
||||
}
|
||||
break;
|
||||
case VHOST_USER_SLAVE_IOTLB_MSG:
|
||||
/* not supported - VIRTIO_F_IOMMU_PLATFORM */
|
||||
case VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG:
|
||||
|
|
@ -684,6 +700,15 @@ static bool vu_notify(struct virtqueue *vq)
|
|||
const uint64_t n = 1;
|
||||
int rc;
|
||||
|
||||
if (info->kick_fd < 0) {
|
||||
struct virtio_uml_device *vu_dev;
|
||||
|
||||
vu_dev = to_virtio_uml_device(vq->vdev);
|
||||
|
||||
return vhost_user_set_vring_state(vu_dev, VHOST_USER_VRING_KICK,
|
||||
vq->index, 0) == 0;
|
||||
}
|
||||
|
||||
do {
|
||||
rc = os_write_file(info->kick_fd, &n, sizeof(n));
|
||||
} while (rc == -EINTR);
|
||||
|
|
@ -749,10 +774,13 @@ static void vu_del_vq(struct virtqueue *vq)
|
|||
{
|
||||
struct virtio_uml_vq_info *info = vq->priv;
|
||||
|
||||
um_free_irq(VIRTIO_IRQ, vq);
|
||||
if (info->call_fd >= 0) {
|
||||
um_free_irq(VIRTIO_IRQ, vq);
|
||||
os_close_file(info->call_fd);
|
||||
}
|
||||
|
||||
os_close_file(info->call_fd);
|
||||
os_close_file(info->kick_fd);
|
||||
if (info->kick_fd >= 0)
|
||||
os_close_file(info->kick_fd);
|
||||
|
||||
vring_del_virtqueue(vq);
|
||||
kfree(info);
|
||||
|
|
@ -782,6 +810,15 @@ static int vu_setup_vq_call_fd(struct virtio_uml_device *vu_dev,
|
|||
int call_fds[2];
|
||||
int rc;
|
||||
|
||||
/* no call FD needed/desired in this case */
|
||||
if (vu_dev->protocol_features &
|
||||
BIT_ULL(VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS) &&
|
||||
vu_dev->protocol_features &
|
||||
BIT_ULL(VHOST_USER_PROTOCOL_F_SLAVE_REQ)) {
|
||||
info->call_fd = -1;
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Use a pipe for call fd, since SIGIO is not supported for eventfd */
|
||||
rc = os_pipe(call_fds, true, true);
|
||||
if (rc < 0)
|
||||
|
|
@ -838,10 +875,15 @@ static struct virtqueue *vu_setup_vq(struct virtio_device *vdev,
|
|||
vq->priv = info;
|
||||
num = virtqueue_get_vring_size(vq);
|
||||
|
||||
rc = os_eventfd(0, 0);
|
||||
if (rc < 0)
|
||||
goto error_kick;
|
||||
info->kick_fd = rc;
|
||||
if (vu_dev->protocol_features &
|
||||
BIT_ULL(VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS)) {
|
||||
info->kick_fd = -1;
|
||||
} else {
|
||||
rc = os_eventfd(0, 0);
|
||||
if (rc < 0)
|
||||
goto error_kick;
|
||||
info->kick_fd = rc;
|
||||
}
|
||||
|
||||
rc = vu_setup_vq_call_fd(vu_dev, vq);
|
||||
if (rc)
|
||||
|
|
@ -866,10 +908,13 @@ static struct virtqueue *vu_setup_vq(struct virtio_device *vdev,
|
|||
return vq;
|
||||
|
||||
error_setup:
|
||||
um_free_irq(VIRTIO_IRQ, vq);
|
||||
os_close_file(info->call_fd);
|
||||
if (info->call_fd >= 0) {
|
||||
um_free_irq(VIRTIO_IRQ, vq);
|
||||
os_close_file(info->call_fd);
|
||||
}
|
||||
error_call:
|
||||
os_close_file(info->kick_fd);
|
||||
if (info->kick_fd >= 0)
|
||||
os_close_file(info->kick_fd);
|
||||
error_kick:
|
||||
vring_del_virtqueue(vq);
|
||||
error_create:
|
||||
|
|
@ -908,10 +953,12 @@ static int vu_find_vqs(struct virtio_device *vdev, unsigned nvqs,
|
|||
list_for_each_entry(vq, &vdev->vqs, list) {
|
||||
struct virtio_uml_vq_info *info = vq->priv;
|
||||
|
||||
rc = vhost_user_set_vring_kick(vu_dev, vq->index,
|
||||
info->kick_fd);
|
||||
if (rc)
|
||||
goto error_setup;
|
||||
if (info->kick_fd >= 0) {
|
||||
rc = vhost_user_set_vring_kick(vu_dev, vq->index,
|
||||
info->kick_fd);
|
||||
if (rc)
|
||||
goto error_setup;
|
||||
}
|
||||
|
||||
rc = vhost_user_set_vring_enable(vu_dev, vq->index, true);
|
||||
if (rc)
|
||||
|
|
@ -1008,6 +1055,8 @@ static int virtio_uml_probe(struct platform_device *pdev)
|
|||
return rc;
|
||||
vu_dev->sock = rc;
|
||||
|
||||
spin_lock_init(&vu_dev->sock_lock);
|
||||
|
||||
rc = vhost_user_init(vu_dev);
|
||||
if (rc)
|
||||
goto error_init;
|
||||
|
|
|
|||
Loading…
Reference in New Issue