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From: "Michael S. Tsirkin" <mst@redhat.com>
To: virtualization@lists.linux-foundation.org, kvm@vger.kernel.org
Cc: David Howells <dhowells@redhat.com>,
	"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
	linux-kernel@vger.kernel.org, Dave Jones <davej@redhat.com>
Subject: [PATCH] virtio_pci: fix capability format, comments
Date: Tue, 28 May 2013 11:08:16 +0300	[thread overview]
Message-ID: <20130528080816.GA23399@redhat.com> (raw)

- queue size can actually be 0 which is not a power of 2
- fix capability format. PCI spec says:
	The layout of the information is vendor specific, except that the byte
	immediately following the “Next” pointer in the capability structure is
	defined to be a length field.
	This length field provides the number of bytes in the capability
	structure (including the ID and Next pointer bytes).

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---

This patch is on top of the new layout branch, too

 include/uapi/linux/virtio_pci.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/include/uapi/linux/virtio_pci.h b/include/uapi/linux/virtio_pci.h
index cda688f..a5ef8cd 100644
--- a/include/uapi/linux/virtio_pci.h
+++ b/include/uapi/linux/virtio_pci.h
@@ -129,6 +129,7 @@
 struct virtio_pci_cap {
 	__u8 cap_vndr;	/* Generic PCI field: PCI_CAP_ID_VNDR */
 	__u8 cap_next;	/* Generic PCI field: next ptr. */
+	__u8 cap_len;	/* Generic PCI field: capability length */
 	__u8 cfg_type;	/* One of the VIRTIO_PCI_CAP_*_CFG. */
 	__u8 bar;		/* Where to find it. */
 	__le32 offset;	/* Offset within bar. */
@@ -154,7 +155,7 @@ struct virtio_pci_common_cfg {
 
 	/* About a specific virtqueue. */
 	__le16 queue_select;		/* read-write */
-	__le16 queue_size;		/* read-write, power of 2. */
+	__le16 queue_size;		/* read-write, power of 2, or 0. */
 	__le16 queue_msix_vector;	/* read-write */
 	__le16 queue_enable;		/* read-write */
 	__le16 queue_notify_off;	/* read-only */
-- 
MST
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WARNING: multiple messages have this Message-ID (diff)
From: "Michael S. Tsirkin" <mst@redhat.com>
To: virtualization@lists.linux-foundation.org, kvm@vger.kernel.org
Cc: Rusty Russell <rusty@rustcorp.com.au>,
	"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
	David Howells <dhowells@redhat.com>,
	Dave Jones <davej@redhat.com>,
	linux-kernel@vger.kernel.org
Subject: [PATCH] virtio_pci: fix capability format, comments
Date: Tue, 28 May 2013 11:08:16 +0300	[thread overview]
Message-ID: <20130528080816.GA23399@redhat.com> (raw)

- queue size can actually be 0 which is not a power of 2
- fix capability format. PCI spec says:
	The layout of the information is vendor specific, except that the byte
	immediately following the “Next” pointer in the capability structure is
	defined to be a length field.
	This length field provides the number of bytes in the capability
	structure (including the ID and Next pointer bytes).

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---

This patch is on top of the new layout branch, too

 include/uapi/linux/virtio_pci.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/include/uapi/linux/virtio_pci.h b/include/uapi/linux/virtio_pci.h
index cda688f..a5ef8cd 100644
--- a/include/uapi/linux/virtio_pci.h
+++ b/include/uapi/linux/virtio_pci.h
@@ -129,6 +129,7 @@
 struct virtio_pci_cap {
 	__u8 cap_vndr;	/* Generic PCI field: PCI_CAP_ID_VNDR */
 	__u8 cap_next;	/* Generic PCI field: next ptr. */
+	__u8 cap_len;	/* Generic PCI field: capability length */
 	__u8 cfg_type;	/* One of the VIRTIO_PCI_CAP_*_CFG. */
 	__u8 bar;		/* Where to find it. */
 	__le32 offset;	/* Offset within bar. */
@@ -154,7 +155,7 @@ struct virtio_pci_common_cfg {
 
 	/* About a specific virtqueue. */
 	__le16 queue_select;		/* read-write */
-	__le16 queue_size;		/* read-write, power of 2. */
+	__le16 queue_size;		/* read-write, power of 2, or 0. */
 	__le16 queue_msix_vector;	/* read-write */
 	__le16 queue_enable;		/* read-write */
 	__le16 queue_notify_off;	/* read-only */
-- 
MST

             reply	other threads:[~2013-05-28  8:08 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-05-28  8:08 Michael S. Tsirkin [this message]
2013-05-28  8:08 ` [PATCH] virtio_pci: fix capability format, comments Michael S. Tsirkin
2013-05-30  1:33 ` Rusty Russell
2013-05-30  1:33   ` Rusty Russell

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