similar to: Opposite return values in vringh_notify_enable_kern() and virtqueue_enable_cb().

From: Sjur Br?ndeland <sjur.brandeland at stericsson.com> This patch-set introduces the CAIF Virtio Link layer driver. This driver depends on Rusty's new host virtio ring implementation, so this patch-set is based on the vringh branch in Rusty's git. Regards, Sjur cc: Rusty Russell <rusty at rustcorp.com.au> cc: Ohad Ben-Cohen <ohad at wizery.com> cc: David S. Miller

From: Sjur Br?ndeland <sjur.brandeland at stericsson.com> This patch-set introduces the CAIF Virtio Link layer driver. This driver depends on Rusty's new host virtio ring implementation, so this patch-set is based on the vringh branch in Rusty's git. Regards, Sjur cc: Rusty Russell <rusty at rustcorp.com.au> cc: Ohad Ben-Cohen <ohad at wizery.com> cc: David S. Miller

Getting use of virtio rings correct is tricky, and a recent patch saw an implementation of in-kernel rings (as separate from userspace). This patch attempts to abstract the business of dealing with the virtio ring layout from the access (userspace or direct); to do this, we use function pointers, which gcc inlines correctly. Signed-off-by: Rusty Russell <rusty at rustcorp.com.au> ---

Getting use of virtio rings correct is tricky, and a recent patch saw an implementation of in-kernel rings (as separate from userspace). This patch attempts to abstract the business of dealing with the virtio ring layout from the access (userspace or direct); to do this, we use function pointers, which gcc inlines correctly. Signed-off-by: Rusty Russell <rusty at rustcorp.com.au> ---

From: Sjur Br?ndeland <sjur.brandeland at stericsson.com> This driver depends on Rusty's new host virtio ring implementation, so this patch-set is based on the vringh branch in Rusty's git. Changes since V1: - Use the new iov helper functions, and simplify iov handling. However this triggers compile warnings, as it takes struct iov while kernel api uses struct kiov - Introduced

From: Sjur Br?ndeland <sjur.brandeland at stericsson.com> This driver depends on Rusty's new host virtio ring implementation, so this patch-set is based on the vringh branch in Rusty's git. Changes since V1: - Use the new iov helper functions, and simplify iov handling. However this triggers compile warnings, as it takes struct iov while kernel api uses struct kiov - Introduced

Check on the correct return value from vringh_notify_enable_kern(). It returns false if more packets are available, not true. Signed-off-by: Sjur Br?ndeland <sjur.brandeland at stericsson.com> --- Hi, This patch applies to Rusty's virtio-next branch. Thanks, Sjur drivers/net/caif/caif_virtio.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git

Check on the correct return value from vringh_notify_enable_kern(). It returns false if more packets are available, not true. Signed-off-by: Sjur Br?ndeland <sjur.brandeland at stericsson.com> --- Hi, This patch applies to Rusty's virtio-next branch. Thanks, Sjur drivers/net/caif/caif_virtio.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git

This introduces vringh, which are generic accessors for virtio rings (host side). There's a host-side implementation in vhost, but it assumes that the rings are in userspace, and is tied to the vhost implementation. I have patches to adapt it to use vringh, but I'm pushing this in the next merge window for Sjur, who has CAIF patches which need it. This also includes a test program in

This introduces vringh, which are generic accessors for virtio rings (host side). There's a host-side implementation in vhost, but it assumes that the rings are in userspace, and is tied to the vhost implementation. I have patches to adapt it to use vringh, but I'm pushing this in the next merge window for Sjur, who has CAIF patches which need it. This also includes a test program in

From: Sjur Br?ndeland <sjur.brandeland at stericsson.com> Add wrappers for the host vrings to support loose coupling between the virtio device and driver. A new struct vringh_config_ops with the functions find_vrhs() and del_vrhs() is added to the virtio_device struct. This enables virtio drivers to manage virtio host rings without detailed knowledge of how the vrings are created and

From: Sjur Br?ndeland <sjur.brandeland at stericsson.com> Add wrappers for the host vrings to support loose coupling between the virtio device and driver. A new struct vringh_config_ops with the functions find_vrhs() and del_vrhs() is added to the virtio_device struct. This enables virtio drivers to manage virtio host rings without detailed knowledge of how the vrings are created and

Implement the vringh callback functions in order to manage host virito rings and handle kicks. This allows virtio device to request host-virtio-rings. Signed-off-by: Sjur Br?ndeland <sjur.brandeland at stericsson.com> --- Hi Ohad and Rusty, This v2 version is simpler, more readable and verbose (+50 lines) compared to the previous patch. This patch probably should to go via Rusty's

Implement the vringh callback functions in order to manage host virito rings and handle kicks. This allows virtio device to request host-virtio-rings. Signed-off-by: Sjur Br?ndeland <sjur.brandeland at stericsson.com> --- Hi Ohad and Rusty, This v2 version is simpler, more readable and verbose (+50 lines) compared to the previous patch. This patch probably should to go via Rusty's

From: Sjur Br?ndeland <sjur.brandeland at stericsson.com> Add wrappers for the host vrings to support loose coupling between the virtio device and driver. The functions find_vrhs() and del_vrhs() are added to struct virtio_config_ops to manage the host vrings. The function vringh_notify() is added so the guest can be kicked when buffers are added to the used-ring. This enables the virtio

From: Sjur Br?ndeland <sjur.brandeland at stericsson.com> Add wrappers for the host vrings to support loose coupling between the virtio device and driver. The functions find_vrhs() and del_vrhs() are added to struct virtio_config_ops to manage the host vrings. The function vringh_notify() is added so the guest can be kicked when buffers are added to the used-ring. This enables the virtio

struct vring (in the uapi directory) and supporting APIs 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 struct vring, add

This adds a way to check ring empty state after enable_cb outside any locks. Will be used by virtio_net. Note: there's room for more optimization: caller is likely to have a memory barrier already, which means we might be able to get rid of a barrier here. Deferring this optimization until we do some benchmarking. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> ---

This adds a way to check ring empty state after enable_cb outside any locks. Will be used by virtio_net. Note: there's room for more optimization: caller is likely to have a memory barrier already, which means we might be able to get rid of a barrier here. Deferring this optimization until we do some benchmarking. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> ---

Jason Wang <jasowang at redhat.com> writes: > We currently does: > > bufs = (avail->idx - last_used_idx) * 3 / 4; > > This is ok now since we only try to enable the delayed callbacks when > the queue is about to be full. This may not work well when there is > only one pending buffer in the virtqueue (this may be the case after > tx interrupt was enabled). Since