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 v7 11/19] virtio: add legacy init/size APIs
Date: Mon, 6 Apr 2020 21:07:49 -0400 [thread overview]
Message-ID: <20200407010700.446571-12-mst@redhat.com> (raw)
In-Reply-To: <20200407010700.446571-1-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:[~2020-04-07 1:07 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-04-07 1:07 [PATCH v7 00/19] virtio: alignment issues Michael S. Tsirkin
2020-04-07 1:07 ` [PATCH v7 01/19] tools/virtio: define aligned attribute Michael S. Tsirkin
2020-04-07 1:07 ` [PATCH v7 02/19] tools/virtio: make asm/barrier.h self contained Michael S. Tsirkin
2020-04-07 1:07 ` [PATCH v7 03/19] tools/virtio: define __KERNEL__ Michael S. Tsirkin
2020-04-07 1:07 ` [PATCH v7 04/19] virtio: add VIRTIO_RING_NO_LEGACY Michael S. Tsirkin
2020-04-07 1:07 ` [PATCH v7 05/19] virtgpu: pull in uaccess.h Michael S. Tsirkin
2020-04-07 1:07 ` [PATCH v7 06/19] virtio-rng: pull in slab.h Michael S. Tsirkin
2020-04-07 1:07 ` [PATCH v7 07/19] remoteproc: " Michael S. Tsirkin
2020-04-07 1:07 ` [PATCH v7 08/19] virtio_input: " Michael S. Tsirkin
2020-04-07 1:07 ` [PATCH v7 09/19] virtio: stop using legacy struct vring in kernel Michael S. Tsirkin
2020-04-07 1:07 ` [PATCH v7 10/19] vhost: force spec specified alignment on types Michael S. Tsirkin
2020-04-07 1:07 ` Michael S. Tsirkin [this message]
2020-04-07 1:07 ` [PATCH v7 12/19] virtio_ring: switch to virtio_legacy_init/size Michael S. Tsirkin
2020-04-07 1:07 ` [PATCH v7 13/19] tools/virtio: " Michael S. Tsirkin
2020-04-07 1:07 ` [PATCH v7 14/19] vop: " Michael S. Tsirkin
2020-04-07 1:08 ` [PATCH v7 15/19] remoteproc: " Michael S. Tsirkin
2020-04-07 1:08 ` [PATCH v7 16/19] mellanox: " Michael S. Tsirkin
2020-04-07 1:08 ` [PATCH v7 17/19] vhost: option to fetch descriptors through an independent struct Michael S. Tsirkin
2020-04-07 1:08 ` [PATCH v7 18/19] vhost: use batched version by default Michael S. Tsirkin
2020-04-07 1:08 ` [PATCH v7 19/19] vhost: batching fetches Michael S. Tsirkin
2020-04-07 3:41 ` [PATCH v7 00/19] virtio: alignment issues Jason Wang
2020-04-07 9:48 ` Michael S. Tsirkin
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