RE: [RFC 09/11] HID: hyperv: Make ringbuffer at least take two pages

[Michael Kelley]

From: Boqun Feng <boqun.feng@xxxxxxxxx> Sent: Monday, July 20, 2020 6:42 PM
> 
> When PAGE_SIZE > HV_HYP_PAGE_SIZE, we need the ringbuffer size to be at
> least 2 * PAGE_SIZE: one page for the header and at least one page of
> the data part (because of the alignment requirement for double mapping).
> 
> So make sure the ringbuffer sizes to be at least 2 * PAGE_SIZE when
> using vmbus_open() to establish the vmbus connection.
> 
> Signed-off-by: Boqun Feng <boqun.feng@xxxxxxxxx>
> ---
>  drivers/hid/hid-hyperv.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/hid/hid-hyperv.c b/drivers/hid/hid-hyperv.c
> index 0b6ee1dee625..36c5e157c691 100644
> --- a/drivers/hid/hid-hyperv.c
> +++ b/drivers/hid/hid-hyperv.c
> @@ -104,8 +104,8 @@ struct synthhid_input_report {
> 
>  #pragma pack(pop)
> 
> -#define INPUTVSC_SEND_RING_BUFFER_SIZE		(40 * 1024)
> -#define INPUTVSC_RECV_RING_BUFFER_SIZE		(40 * 1024)
> +#define INPUTVSC_SEND_RING_BUFFER_SIZE		(128 * 1024)
> +#define INPUTVSC_RECV_RING_BUFFER_SIZE		(128 * 1024)

Use max(40 * 1024, 2 * PAGE_SIZE) like in patch 8 of the series?

> 
> 
>  enum pipe_prot_msg_type {
> --
> 2.27.0