From: "Michael S. Tsirkin" <mst@redhat.com>
To: linux-kernel@vger.kernel.org
Cc: Jason Wang <jasowang@redhat.com>,
virtualization@lists.linux-foundation.org
Subject: [PATCH v5 07/12] virtio: add legacy init/size APIs
Date: Mon, 6 Apr 2020 17:35:07 -0400 [thread overview]
Message-ID: <20200406213314.248038-8-mst@redhat.com> (raw)
In-Reply-To: <20200406213314.248038-1-mst@redhat.com>
vring_init/vring_size (in the uapi directory) are kept
around to solely avoid breaking old userspace builds.
It's not actually part of the UAPI - it was kept in the UAPI
header by mistake, and using it in kernel isn't necessary
and prevents us from making changes safely.
In particular, the APIs actually assume the legacy layout.
Add an internal kernel-only vring_legacy_init/vring_legacy_size.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
include/linux/virtio_ring.h | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)
diff --git a/include/linux/virtio_ring.h b/include/linux/virtio_ring.h
index c3f9ca054250..766d70bca492 100644
--- a/include/linux/virtio_ring.h
+++ b/include/linux/virtio_ring.h
@@ -140,4 +140,22 @@ void vring_del_virtqueue(struct virtqueue *vq);
void vring_transport_features(struct virtio_device *vdev);
irqreturn_t vring_interrupt(int irq, void *_vq);
+
+static inline void vring_legacy_init(struct vring *vr, unsigned int num, void *p,
+ unsigned long align)
+{
+ vr->num = num;
+ vr->desc = p;
+ vr->avail = (struct vring_avail *)((char *)p + num * sizeof(struct vring_desc));
+ vr->used = (void *)(((uintptr_t)&vr->avail->ring[num] + sizeof(__virtio16)
+ + align-1) & ~(align - 1));
+}
+
+static inline unsigned vring_legacy_size(unsigned int num, unsigned long align)
+{
+ return ((sizeof(struct vring_desc) * num + sizeof(__virtio16) * (3 + num)
+ + align - 1) & ~(align - 1))
+ + sizeof(__virtio16) * 3 + sizeof(struct vring_used_elem) * num;
+}
+
#endif /* _LINUX_VIRTIO_RING_H */
--
MST
next prev parent reply other threads:[~2020-04-06 21:35 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-04-06 21:34 [PATCH v5 00/12] virtio: alignment issues Michael S. Tsirkin
2020-04-06 21:34 ` [PATCH v5 01/12] tools/virtio: define aligned attribute Michael S. Tsirkin
2020-04-06 21:34 ` [PATCH v5 02/12] tools/virtio: make asm/barrier.h self contained Michael S. Tsirkin
2020-04-06 21:34 ` [PATCH v5 03/12] tools/virtio: define __KERNEL__ Michael S. Tsirkin
2020-04-06 21:35 ` [PATCH v5 04/12] virtio: add VIRTIO_RING_NO_LEGACY Michael S. Tsirkin
2020-04-06 21:35 ` [PATCH v5 05/12] virtio: stop using legacy struct vring in kernel Michael S. Tsirkin
2020-04-06 21:35 ` [PATCH v5 06/12] vhost: force spec specified alignment on types Michael S. Tsirkin
2020-04-06 21:35 ` Michael S. Tsirkin [this message]
2020-04-06 21:35 ` [PATCH v5 08/12] virtio_ring: switch to virtio_legacy_init/size Michael S. Tsirkin
2020-04-06 21:35 ` [PATCH v5 09/12] tools/virtio: " Michael S. Tsirkin
2020-04-06 21:35 ` [PATCH v5 10/12] vop: " Michael S. Tsirkin
2020-04-06 21:35 ` [PATCH v5 11/12] remoteproc: " Michael S. Tsirkin
2020-04-06 21:35 ` [PATCH v5 12/12] mellanox: " Michael S. Tsirkin
2020-04-06 21:57 ` Andy Shevchenko
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200406213314.248038-8-mst@redhat.com \
--to=mst@redhat.com \
--cc=jasowang@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=virtualization@lists.linux-foundation.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).