On Tue, 22 Nov 2011 20:36:22 +0200, "Michael S. Tsirkin" <mst@xxxxxxxxxx> wrote:
> Here's an updated vesion.
> I'm alternating between updating the spec and the driver,
> spec update to follow.
Don't touch the spec yet, we have a long way to go :(
I want the ability for driver to set the ring size, and the device to
set the alignment. That's a bigger change than you have here. I
imagine it almost rips the driver into two completely different drivers.
This is the kind of thing I had in mind, for the header. Want me to
code up the rest?
(I've avoided adding the constants for the new layout: a struct is more
compact and more descriptive).
Cheers,
Rusty.
diff --git a/include/linux/virtio_pci.h b/include/linux/virtio_pci.h
--- a/include/linux/virtio_pci.h
+++ b/include/linux/virtio_pci.h
@@ -42,56 +42,74 @@
#include <linux/virtio_config.h>
/* A 32-bit r/o bitmask of the features supported by the host */
-#define VIRTIO_PCI_HOST_FEATURES 0
+#define VIRTIO_PCI_LEGACY_HOST_FEATURES 0
/* A 32-bit r/w bitmask of features activated by the guest */
-#define VIRTIO_PCI_GUEST_FEATURES 4
+#define VIRTIO_PCI_LEGACY_GUEST_FEATURES 4
/* A 32-bit r/w PFN for the currently selected queue */
-#define VIRTIO_PCI_QUEUE_PFN 8
+#define VIRTIO_PCI_LEGACY_QUEUE_PFN 8
/* A 16-bit r/o queue size for the currently selected queue */
-#define VIRTIO_PCI_QUEUE_NUM 12
+#define VIRTIO_PCI_LEGACY_QUEUE_NUM 12
/* A 16-bit r/w queue selector */
-#define VIRTIO_PCI_QUEUE_SEL 14
+#define VIRTIO_PCI_LEGACY_QUEUE_SEL 14
/* A 16-bit r/w queue notifier */
-#define VIRTIO_PCI_QUEUE_NOTIFY 16
+#define VIRTIO_PCI_LEGACY_QUEUE_NOTIFY 16
/* An 8-bit device status register. */
-#define VIRTIO_PCI_STATUS 18
+#define VIRTIO_PCI_LEGACY_STATUS 18
/* An 8-bit r/o interrupt status register. Reading the value will return the
* current contents of the ISR and will also clear it. This is effectively
* a read-and-acknowledge. */
-#define VIRTIO_PCI_ISR 19
-
-/* The bit of the ISR which indicates a device configuration change. */
-#define VIRTIO_PCI_ISR_CONFIG 0x2
+#define VIRTIO_PCI_LEGACY_ISR 19
/* MSI-X registers: only enabled if MSI-X is enabled. */
/* A 16-bit vector for configuration changes. */
-#define VIRTIO_MSI_CONFIG_VECTOR 20
+#define VIRTIO_MSI_LEGACY_CONFIG_VECTOR 20
/* A 16-bit vector for selected queue notifications. */
-#define VIRTIO_MSI_QUEUE_VECTOR 22
-/* Vector value used to disable MSI for queue */
-#define VIRTIO_MSI_NO_VECTOR 0xffff
+#define VIRTIO_MSI_LEGACY_QUEUE_VECTOR 22
/* The remaining space is defined by each driver as the per-driver
* configuration space */
-#define VIRTIO_PCI_CONFIG(dev) ((dev)->msix_enabled ? 24 : 20)
+#define VIRTIO_PCI_LEGACY_CONFIG(dev) ((dev)->msix_enabled ? 24 : 20)
+
+/* How many bits to shift physical queue address written to QUEUE_PFN.
+ * 12 is historical, and due to x86 page size. */
+#define VIRTIO_PCI_LEGACY_QUEUE_ADDR_SHIFT 12
+
+/* The alignment to use between consumer and producer parts of vring.
+ * x86 pagesize again. */
+#define VIRTIO_PCI_LEGACY_VRING_ALIGN 4096
+
+#ifndef __KERNEL__
+/* Don't break compile of old userspace code. These will go away. */
+#define VIRTIO_PCI_HOST_FEATURES VIRTIO_PCI_LEGACY_HOST_FEATURES
+#define VIRTIO_PCI_GUEST_FEATURES VIRTIO_PCI_LEGACY_GUEST_FEATURES
+#define VIRTIO_PCI_LEGACY_QUEUE_PFN VIRTIO_PCI_QUEUE_PFN
+#define VIRTIO_PCI_LEGACY_QUEUE_NUM VIRTIO_PCI_QUEUE_NUM
+#define VIRTIO_PCI_LEGACY_QUEUE_SEL VIRTIO_PCI_QUEUE_SEL
+#define VIRTIO_PCI_LEGACY_QUEUE_NOTIFY VIRTIO_PCI_QUEUE_NOTIFY
+#define VIRTIO_PCI_LEGACY_STATUS VIRTIO_PCI_STATUS
+#define VIRTIO_PCI_LEGACY_ISR VIRTIO_PCI_ISR
+#define VIRTIO_MSI_LEGACY_CONFIG_VECTOR VIRTIO_MSI_CONFIG_VECTOR
+#define VIRTIO_MSI_LEGACY_QUEUE_VECTOR VIRTIO_MSI_QUEUE_VECTOR
+#define VIRTIO_PCI_LEGACY_CONFIG(dev) VIRTIO_PCI_CONFIG(dev)
+#define VIRTIO_PCI_LEGACY_QUEUE_ADDR_SHIFT VIRTIO_PCI_QUEUE_ADDR_SHIFT
+#define VIRTIO_PCI_LEGACY_VRING_ALIGN VIRTIO_PCI_VRING_ALIGN
+#endif /* ...!KERNEL */
/* Virtio ABI version, this must match exactly */
#define VIRTIO_PCI_ABI_VERSION 0
-/* How many bits to shift physical queue address written to QUEUE_PFN.
- * 12 is historical, and due to x86 page size. */
-#define VIRTIO_PCI_QUEUE_ADDR_SHIFT 12
+/* Vector value used to disable MSI for queue */
+#define VIRTIO_MSI_NO_VECTOR 0xffff
-/* The alignment to use between consumer and producer parts of vring.
- * x86 pagesize again. */
-#define VIRTIO_PCI_VRING_ALIGN 4096
+/* The bit of the ISR which indicates a device configuration change. */
+#define VIRTIO_PCI_ISR_CONFIG 0x2
/*
* Layout for Virtio PCI vendor specific capability (little-endian):
@@ -133,4 +151,20 @@
#define VIRTIO_PCI_CAP_CFG_OFF_MASK 0xffffffff
#define VIRTIO_PCI_CAP_CFG_OFF_SHIFT 0
+/* Fields in VIRTIO_PCI_CAP_COMMON_CFG: */
+struct virtio_pci_common_cfg {
+ /* About the whole device. */
+ __u64 device_features; /* read-only */
+ __u64 guest_features; /* read-write */
+ __u64 queue_address; /* read-write */
+ __u16 msix_config; /* read-write */
+ __u8 device_status; /* read-write */
+ __u8 unused;
+
+ /* About a specific virtqueue. */
+ __u16 queue_select; /* read-write */
+ __u16 queue_align; /* read-write, power of 2. */
+ __u16 queue_size; /* read-write, power of 2. */
+ __u16 queue_msix_vector;/* read-write */
+};
#endif
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