Add support for the new avail_event feature in vhost_net and vhost test modules. Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx> --- drivers/vhost/net.c | 12 ++++---- drivers/vhost/test.c | 6 ++-- drivers/vhost/vhost.c | 65 +++++++++++++++++++++++++++++++++++++------------ drivers/vhost/vhost.h | 17 +++++++------ 4 files changed, 67 insertions(+), 33 deletions(-) diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index 2f7c76a..e224a92 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -144,7 +144,7 @@ static void handle_tx(struct vhost_net *net) } mutex_lock(&vq->mutex); - vhost_disable_notify(vq); + vhost_disable_notify(&net->dev, vq); if (wmem < sock->sk->sk_sndbuf / 2) tx_poll_stop(net); @@ -166,8 +166,8 @@ static void handle_tx(struct vhost_net *net) set_bit(SOCK_ASYNC_NOSPACE, &sock->flags); break; } - if (unlikely(vhost_enable_notify(vq))) { - vhost_disable_notify(vq); + if (unlikely(vhost_enable_notify(&net->dev, vq))) { + vhost_disable_notify(&net->dev, vq); continue; } break; @@ -315,7 +315,7 @@ static void handle_rx(struct vhost_net *net) return; mutex_lock(&vq->mutex); - vhost_disable_notify(vq); + vhost_disable_notify(&net->dev, vq); vhost_hlen = vq->vhost_hlen; sock_hlen = vq->sock_hlen; @@ -334,10 +334,10 @@ static void handle_rx(struct vhost_net *net) break; /* OK, now we need to know about added descriptors. */ if (!headcount) { - if (unlikely(vhost_enable_notify(vq))) { + if (unlikely(vhost_enable_notify(&net->dev, vq))) { /* They have slipped one in as we were * doing that: check again. */ - vhost_disable_notify(vq); + vhost_disable_notify(&net->dev, vq); continue; } /* Nothing new? Wait for eventfd to tell us diff --git a/drivers/vhost/test.c b/drivers/vhost/test.c index 099f302..734e1d7 100644 --- a/drivers/vhost/test.c +++ b/drivers/vhost/test.c @@ -49,7 +49,7 @@ static void handle_vq(struct vhost_test *n) return; mutex_lock(&vq->mutex); - vhost_disable_notify(vq); + vhost_disable_notify(&n->dev, vq); for (;;) { head = vhost_get_vq_desc(&n->dev, vq, vq->iov, @@ -61,8 +61,8 @@ static void handle_vq(struct vhost_test *n) break; /* Nothing new? Wait for eventfd to tell us they refilled. */ if (head == vq->num) { - if (unlikely(vhost_enable_notify(vq))) { - vhost_disable_notify(vq); + if (unlikely(vhost_enable_notify(&n->dev, vq))) { + vhost_disable_notify(&n->dev, vq); continue; } break; diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index e33d5a3..2aea4cb 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -38,6 +38,7 @@ enum { }; #define vhost_used_event(vq) ((u16 __user *)&vq->avail->ring[vq->num]) +#define vhost_avail_event(vq) ((u16 __user *)&vq->used->ring[vq->num]) static void vhost_poll_func(struct file *file, wait_queue_head_t *wqh, poll_table *pt) @@ -499,11 +500,12 @@ static int vq_access_ok(struct vhost_dev *d, unsigned int num, struct vring_used __user *used) { size_t sa = vhost_has_feature(d, VIRTIO_RING_F_USED_EVENT_IDX) ? 2 : 0; + size_t su = vhost_has_feature(d, VIRTIO_RING_F_AVAIL_EVENT_IDX) ? 2 : 0; return access_ok(VERIFY_READ, desc, num * sizeof *desc) && access_ok(VERIFY_READ, avail, sizeof *avail + num * sizeof *avail->ring + sa) && access_ok(VERIFY_WRITE, used, - sizeof *used + num * sizeof *used->ring); + sizeof *used + num * sizeof *used->ring + su); } /* Can we log writes? */ @@ -519,9 +521,11 @@ int vhost_log_access_ok(struct vhost_dev *dev) /* Verify access for write logging. */ /* Caller should have vq mutex and device mutex */ -static int vq_log_access_ok(struct vhost_virtqueue *vq, void __user *log_base) +static int vq_log_access_ok(struct vhost_dev *d, struct vhost_virtqueue *vq, + void __user *log_base) { struct vhost_memory *mp; + size_t s = vhost_has_feature(d, VIRTIO_RING_F_AVAIL_EVENT_IDX) ? 2 : 0; mp = rcu_dereference_protected(vq->dev->memory, lockdep_is_held(&vq->mutex)); @@ -529,7 +533,7 @@ static int vq_log_access_ok(struct vhost_virtqueue *vq, void __user *log_base) vhost_has_feature(vq->dev, VHOST_F_LOG_ALL)) && (!vq->log_used || log_access_ok(log_base, vq->log_addr, sizeof *vq->used + - vq->num * sizeof *vq->used->ring)); + vq->num * sizeof *vq->used->ring + s)); } /* Can we start vq? */ @@ -537,7 +541,7 @@ static int vq_log_access_ok(struct vhost_virtqueue *vq, void __user *log_base) int vhost_vq_access_ok(struct vhost_virtqueue *vq) { return vq_access_ok(vq->dev, vq->num, vq->desc, vq->avail, vq->used) && - vq_log_access_ok(vq, vq->log_base); + vq_log_access_ok(vq->dev, vq, vq->log_base); } static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m) @@ -824,7 +828,7 @@ long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, unsigned long arg) vq = d->vqs + i; mutex_lock(&vq->mutex); /* If ring is inactive, will check when it's enabled. */ - if (vq->private_data && !vq_log_access_ok(vq, base)) + if (vq->private_data && !vq_log_access_ok(d, vq, base)) r = -EFAULT; else vq->log_base = base; @@ -1225,6 +1229,10 @@ int vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq, /* On success, increment avail index. */ vq->last_avail_idx++; + + /* Assume notifications from guest are disabled at this point, + * if they aren't we would need to update avail_event index. */ + BUG_ON(!(vq->used_flags & VRING_USED_F_NO_NOTIFY)); return head; } @@ -1414,7 +1422,7 @@ void vhost_add_used_and_signal_n(struct vhost_dev *dev, } /* OK, now we need to know about added descriptors. */ -bool vhost_enable_notify(struct vhost_virtqueue *vq) +bool vhost_enable_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) { u16 avail_idx; int r; @@ -1422,11 +1430,34 @@ bool vhost_enable_notify(struct vhost_virtqueue *vq) if (!(vq->used_flags & VRING_USED_F_NO_NOTIFY)) return false; vq->used_flags &= ~VRING_USED_F_NO_NOTIFY; - r = put_user(vq->used_flags, &vq->used->flags); - if (r) { - vq_err(vq, "Failed to enable notification at %p: %d\n", - &vq->used->flags, r); - return false; + if (!vhost_has_feature(dev, VIRTIO_RING_F_AVAIL_EVENT_IDX)) { + r = put_user(vq->used_flags, &vq->used->flags); + if (r) { + vq_err(vq, "Failed to enable notification at %p: %d\n", + &vq->used->flags, r); + return false; + } + } else { + r = put_user(vq->last_avail_idx, vhost_avail_event(vq)); + if (r) { + vq_err(vq, "Failed to update avail event index at %p: %d\n", + vhost_avail_event(vq), r); + return false; + } + } + if (unlikely(vq->log_used)) { + void __user *used; + /* Make sure data is seen before log. */ + smp_wmb(); + used = vhost_has_feature(dev, VIRTIO_RING_F_AVAIL_EVENT_IDX) ? + &vq->used->flags : vhost_avail_event(vq); + /* Log used flags or event index entry write. Both are 16 bit + * fields. */ + log_write(vq->log_base, vq->log_addr + + (used - (void __user *)vq->used), + sizeof(u16)); + if (vq->log_ctx) + eventfd_signal(vq->log_ctx, 1); } /* They could have slipped one in as we were doing that: make * sure it's written, then check again. */ @@ -1442,15 +1473,17 @@ bool vhost_enable_notify(struct vhost_virtqueue *vq) } /* We don't need to be notified again. */ -void vhost_disable_notify(struct vhost_virtqueue *vq) +void vhost_disable_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) { int r; if (vq->used_flags & VRING_USED_F_NO_NOTIFY) return; vq->used_flags |= VRING_USED_F_NO_NOTIFY; - r = put_user(vq->used_flags, &vq->used->flags); - if (r) - vq_err(vq, "Failed to enable notification at %p: %d\n", - &vq->used->flags, r); + if (!vhost_has_feature(dev, VIRTIO_RING_F_AVAIL_EVENT_IDX)) { + r = put_user(vq->used_flags, &vq->used->flags); + if (r) + vq_err(vq, "Failed to enable notification at %p: %d\n", + &vq->used->flags, r); + } } diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index 5825ac6..edf84be 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -155,8 +155,8 @@ void vhost_add_used_and_signal(struct vhost_dev *, struct vhost_virtqueue *, void vhost_add_used_and_signal_n(struct vhost_dev *, struct vhost_virtqueue *, struct vring_used_elem *heads, unsigned count); void vhost_signal(struct vhost_dev *, struct vhost_virtqueue *); -void vhost_disable_notify(struct vhost_virtqueue *); -bool vhost_enable_notify(struct vhost_virtqueue *); +void vhost_disable_notify(struct vhost_dev *, struct vhost_virtqueue *); +bool vhost_enable_notify(struct vhost_dev *, struct vhost_virtqueue *); int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log, unsigned int log_num, u64 len); @@ -168,12 +168,13 @@ int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log, } while (0) enum { - VHOST_FEATURES = (1 << VIRTIO_F_NOTIFY_ON_EMPTY) | - (1 << VIRTIO_RING_F_INDIRECT_DESC) | - (1 << VIRTIO_RING_F_USED_EVENT_IDX) | - (1 << VHOST_F_LOG_ALL) | - (1 << VHOST_NET_F_VIRTIO_NET_HDR) | - (1 << VIRTIO_NET_F_MRG_RXBUF), + VHOST_FEATURES = (1ULL << VIRTIO_F_NOTIFY_ON_EMPTY) | + (1ULL << VIRTIO_RING_F_INDIRECT_DESC) | + (1ULL << VIRTIO_RING_F_USED_EVENT_IDX) | + (1ULL << VIRTIO_RING_F_AVAIL_EVENT_IDX) | + (1ULL << VHOST_F_LOG_ALL) | + (1ULL << VHOST_NET_F_VIRTIO_NET_HDR) | + (1ULL << VIRTIO_NET_F_MRG_RXBUF), }; static inline bool vhost_has_feature(struct vhost_dev *dev, int bit) -- 1.7.5.53.gc233e -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html