[RFC PATCH v4 06/10] vfio: Define device specific irq type capability

Yan Zhao
2020-05-18T03:00:48Z

From: Tina Zhang <tina.zhang@intel.com>

Cap the number of irqs with fixed indexes and use capability chains
to chain device specific irqs.

v2:
- Irq capability index starts from 1.

Signed-off-by: Tina Zhang <tina.zhang@intel.com>
Signed-off-by: Eric Auger <eric.auger@redhat.com>
---
include/uapi/linux/vfio.h | 19 ++++++++++++++++++-
1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
index 0fe7c9a6f211..2d0d85c7c4d4 100644
--- a/include/uapi/linux/vfio.h
+++ b/include/uapi/linux/vfio.h
@@ -683,11 +683,27 @@ struct vfio_irq_info {
#define VFIO_IRQ_INFO_MASKABLE (1 << 1)
#define VFIO_IRQ_INFO_AUTOMASKED (1 << 2)
#define VFIO_IRQ_INFO_NORESIZE (1 << 3)
+#define VFIO_IRQ_INFO_FLAG_CAPS (1 << 4) /* Info supports caps */
__u32 index; /* IRQ index */
__u32 count; /* Number of IRQs within this index */
+ __u32 cap_offset; /* Offset within info struct of first cap */
};
#define VFIO_DEVICE_GET_IRQ_INFO _IO(VFIO_TYPE, VFIO_BASE + 9)

+/*
+ * The irq type capability allows irqs unique to a specific device or
+ * class of devices to be exposed.
+ *
+ * The structures below define version 1 of this capability.
+ */
+#define VFIO_IRQ_INFO_CAP_TYPE 1
+
+struct vfio_irq_info_cap_type {
+ struct vfio_info_cap_header header;
+ __u32 type; /* global per bus driver */
+ __u32 subtype; /* type specific */
+};
+
/**
* VFIO_DEVICE_SET_IRQS - _IOW(VFIO_TYPE, VFIO_BASE + 10, struct vfio_irq_set)
*
@@ -789,7 +805,8 @@ enum {
VFIO_PCI_MSIX_IRQ_INDEX,
VFIO_PCI_ERR_IRQ_INDEX,
VFIO_PCI_REQ_IRQ_INDEX,
- VFIO_PCI_NUM_IRQS
+ VFIO_PCI_NUM_IRQS = 5 /* Fixed user ABI, IRQ indexes >=5 use */
+ /* device specific cap to define content */
};

/*
--
2.17.1