Re: [RFC PATCH 0/2] Enhance RPMsg buffer management

[Mathieu Poirier <mathieu.poirier@linaro.org>]

On Fri, Nov 14, 2025 at 10:46:38AM -0800, Tanmay Shah wrote:
> Take rx and tx buffer size from virtio device config space in the
> resource table. This allows each firmware to configure RPMsg buffer size
> as needed in each direction.
> 
> Original seris:
> https://lore.kernel.org/all/1548949280-31794-1-git-send-email-xiaoxiang@xiaomi.com/
> 
> Following modificaitons are done to the original series:
>   - Separate dma allocation is not done for tx and rx buffers. Instead
>     allocated chunk of memory is split between tx and rx buffers.
>   - If vdev doesn't support VIRTIO_RPMSG_F_BUFSZ feature then use the 
>     default size of 512 bytes for buffers
>   - Change MAX_RPMSG_BUF_SIZE to DEFAULT_RPMSG_BUF_SIZE
>   - move virtio_rpmsg.h from uapi to linux dir
>   - RPMsg buffer size must be set to hold rpmsg header at minimum in the
>     vdev config space of the firmware.
>   - align total buf size to page size when allocating and deallocating
>     memory
> 
> Xiang Xiao (2):
>   rpmsg: virtio_rpmsg_bus: allow the different vring size for send/recv
>   rpmsg: virtio_rpmsg_bus: get buffer size from config space
> 
>  drivers/rpmsg/virtio_rpmsg_bus.c | 105 ++++++++++++++++++++-----------
>  include/linux/virtio_rpmsg.h     |  24 +++++++
>  2 files changed, 93 insertions(+), 36 deletions(-)
>  create mode 100644 include/linux/virtio_rpmsg.h
>

This set is going somewhere.  Please address the comments that were received and
send a new revision.

Apologies for the long review delay.
Mathieu
 
> 
> base-commit: f982fbb1a6ca3553c15763ad9eb2beeae78d3684
> -- 
> 2.34.1
>