dpdk/SOURCES/0002-net-virtio-add-packed-...

142 lines
3.8 KiB
Diff

From 652a2e3a1ba0db81ae1814e8c3cb989e9e89c4e0 Mon Sep 17 00:00:00 2001
From: Jens Freimann <jfreimann@redhat.com>
Date: Mon, 17 Dec 2018 22:31:31 +0100
Subject: [PATCH 02/18] net/virtio: add packed virtqueue helpers
[ upstream commit e9f4feb7e6225f671b59375aff44b9d576121577 ]
Add helper functions to set/clear and check descriptor flags.
Signed-off-by: Jens Freimann <jfreimann@redhat.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
(cherry picked from commit e9f4feb7e6225f671b59375aff44b9d576121577)
Signed-off-by: Jens Freimann <jfreimann@redhat.com>
---
drivers/net/virtio/virtio_pci.h | 6 +++
drivers/net/virtio/virtqueue.h | 72 ++++++++++++++++++++++++++++++++-
2 files changed, 76 insertions(+), 2 deletions(-)
diff --git a/drivers/net/virtio/virtio_pci.h b/drivers/net/virtio/virtio_pci.h
index 4c975a531..b22b62dad 100644
--- a/drivers/net/virtio/virtio_pci.h
+++ b/drivers/net/virtio/virtio_pci.h
@@ -315,6 +315,12 @@ vtpci_with_feature(struct virtio_hw *hw, uint64_t bit)
return (hw->guest_features & (1ULL << bit)) != 0;
}
+static inline int
+vtpci_packed_queue(struct virtio_hw *hw)
+{
+ return vtpci_with_feature(hw, VIRTIO_F_RING_PACKED);
+}
+
/*
* Function declaration from virtio_pci.c
*/
diff --git a/drivers/net/virtio/virtqueue.h b/drivers/net/virtio/virtqueue.h
index 1525c7d10..c32812427 100644
--- a/drivers/net/virtio/virtqueue.h
+++ b/drivers/net/virtio/virtqueue.h
@@ -251,6 +251,31 @@ struct virtio_tx_region {
__attribute__((__aligned__(16)));
};
+static inline int
+desc_is_used(struct vring_packed_desc *desc, struct virtqueue *vq)
+{
+ uint16_t used, avail, flags;
+
+ flags = desc->flags;
+ used = !!(flags & VRING_DESC_F_USED(1));
+ avail = !!(flags & VRING_DESC_F_AVAIL(1));
+
+ return avail == used && used == vq->used_wrap_counter;
+}
+
+
+static inline void
+vring_desc_init_packed(struct virtqueue *vq, int n)
+{
+ int i;
+ for (i = 0; i < n - 1; i++) {
+ vq->ring_packed.desc_packed[i].id = i;
+ vq->vq_descx[i].next = i + 1;
+ }
+ vq->ring_packed.desc_packed[i].id = i;
+ vq->vq_descx[i].next = VQ_RING_DESC_CHAIN_END;
+}
+
/* Chain all the descriptors in the ring with an END */
static inline void
vring_desc_init(struct vring_desc *dp, uint16_t n)
@@ -262,13 +287,53 @@ vring_desc_init(struct vring_desc *dp, uint16_t n)
dp[i].next = VQ_RING_DESC_CHAIN_END;
}
+/**
+ * Tell the backend not to interrupt us.
+ */
+static inline void
+virtqueue_disable_intr_packed(struct virtqueue *vq)
+{
+ uint16_t *event_flags = &vq->ring_packed.driver_event->desc_event_flags;
+
+ *event_flags = RING_EVENT_FLAGS_DISABLE;
+}
+
+
/**
* Tell the backend not to interrupt us.
*/
static inline void
virtqueue_disable_intr(struct virtqueue *vq)
{
- vq->vq_ring.avail->flags |= VRING_AVAIL_F_NO_INTERRUPT;
+ if (vtpci_packed_queue(vq->hw))
+ virtqueue_disable_intr_packed(vq);
+ else
+ vq->vq_ring.avail->flags |= VRING_AVAIL_F_NO_INTERRUPT;
+}
+
+/**
+ * Tell the backend to interrupt. Implementation for packed virtqueues.
+ */
+static inline void
+virtqueue_enable_intr_packed(struct virtqueue *vq)
+{
+ uint16_t *event_flags = &vq->ring_packed.driver_event->desc_event_flags;
+
+
+ if (vq->event_flags_shadow == RING_EVENT_FLAGS_DISABLE) {
+ virtio_wmb();
+ vq->event_flags_shadow = RING_EVENT_FLAGS_ENABLE;
+ *event_flags = vq->event_flags_shadow;
+ }
+}
+
+/**
+ * Tell the backend to interrupt. Implementation for split virtqueues.
+ */
+static inline void
+virtqueue_enable_intr_split(struct virtqueue *vq)
+{
+ vq->vq_ring.avail->flags &= (~VRING_AVAIL_F_NO_INTERRUPT);
}
/**
@@ -277,7 +342,10 @@ virtqueue_disable_intr(struct virtqueue *vq)
static inline void
virtqueue_enable_intr(struct virtqueue *vq)
{
- vq->vq_ring.avail->flags &= (~VRING_AVAIL_F_NO_INTERRUPT);
+ if (vtpci_packed_queue(vq->hw))
+ virtqueue_enable_intr_packed(vq);
+ else
+ virtqueue_enable_intr_split(vq);
}
/**
--
2.21.0