Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Eric Auger <eric.auger@redhat.com>
To:     eric.auger.pro@gmail.com, eric.auger@redhat.com,
        iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu, joro@8bytes.org,
        alex.williamson@redhat.com, jacob.jun.pan@linux.intel.com,
        yi.l.liu@intel.com, jean-philippe.brucker@arm.com,
        will.deacon@arm.com, robin.murphy@arm.com
Cc:     kevin.tian@intel.com, ashok.raj@intel.com, marc.zyngier@arm.com,
        peter.maydell@linaro.org, vincent.stehle@arm.com,
        zhangfei.gao@gmail.com, tina.zhang@intel.com
Subject: [PATCH v9 07/11] vfio: Use capability chains to handle device specific irq
Date:   Thu, 11 Jul 2019 15:56:21 +0200
Message-Id: <20190711135625.20684-8-eric.auger@redhat.com>
In-Reply-To: <20190711135625.20684-1-eric.auger@redhat.com>
References: <20190711135625.20684-1-eric.auger@redhat.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

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

Caps the number of irqs with fixed indexes and uses capability chains
to chain device specific irqs.

Signed-off-by: Tina Zhang <tina.zhang@intel.com>
Signed-off-by: Eric Auger <eric.auger@redhat.com>
[Eric: Put cap_offset at the end of the vfio_irq_info struct,
remove GFX IRQ at the moment and remove any reference to this latter
in the commit message]

---
---
 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 bec761edae9b..b53714ae02c5 100644
--- a/include/uapi/linux/vfio.h
+++ b/include/uapi/linux/vfio.h
@@ -452,11 +452,27 @@ 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      3
+
+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)
  *
@@ -558,7 +574,8 @@ 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 */
 };
 
 /*
-- 
2.20.1