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-rw-r--r--virtio-v1.0-wd01-part1-specification.txt29
1 files changed, 13 insertions, 16 deletions
diff --git a/virtio-v1.0-wd01-part1-specification.txt b/virtio-v1.0-wd01-part1-specification.txt
index 9af2072..e6f23ff 100644
--- a/virtio-v1.0-wd01-part1-specification.txt
+++ b/virtio-v1.0-wd01-part1-specification.txt
@@ -1373,9 +1373,7 @@ the different features the driver negotiated.
Often a driver will suppress transmission interrupts using the
VRING_AVAIL_F_NO_INTERRUPT flag (see "2.4.2. Receiving Used Buffers From
The Device") and check for used packets in the transmit path of following
-packets. However, it will still receive interrupts if the
-VIRTIO_F_NOTIFY_ON_EMPTY feature is negotiated, indicating that
-the transmission queue is completely emptied.
+packets.
The normal behavior in this interrupt handler is to retrieve and
new descriptors from the used ring and free the corresponding
@@ -2583,18 +2581,7 @@ contents of the event field. The following events are defined:
2.5. Reserved Feature Bits
=========================
-Currently there are five device-independent feature bits defined:
-
- VIRTIO_F_NOTIFY_ON_EMPTY (24) Negotiating this feature
- indicates that the driver wants an interrupt if the device runs
- out of available descriptors on a virtqueue, even though
- interrupts are suppressed using the VRING_AVAIL_F_NO_INTERRUPT
- flag or the used_event field. An example of this is the
- networking driver: it doesn't need to know every time a packet
- is transmitted, but it does need to free the transmitted
- packets a finite time after they are transmitted. It can avoid
- using a timer if the device interrupts it when all the packets
- are transmitted.
+Currently there are four device-independent feature bits defined:
VIRTIO_F_RING_INDIRECT_DESC (28) Negotiating this feature indicates
that the driver can use descriptors with the VRING_DESC_F_INDIRECT
@@ -2624,11 +2611,21 @@ and should not be used.
Legacy or transitional devices may offer the following:
+VIRTIO_F_NOTIFY_ON_EMPTY (24) Negotiating this feature
+ indicates that the driver wants an interrupt if the device runs
+ out of available descriptors on a virtqueue, even though
+ interrupts are suppressed using the VRING_AVAIL_F_NO_INTERRUPT
+ flag or the used_event field. An example of this is the
+ networking driver: it doesn't need to know every time a packet
+ is transmitted, but it does need to free the transmitted
+ packets a finite time after they are transmitted. It can avoid
+ using a timer if the device interrupts it when all the packets
+ are transmitted.
+
VIRTIO_F_ANY_LAYOUT (27) This feature indicates that the device
accepts arbitrary descriptor layouts, as described in Section
"2.1.4.2.1. Legacy Interface: Message Framing".
-
2.6. virtio_ring.h
=================