From: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Sent: Wednesday, January 10, 2024 10:38 AM
>
> The second half of the if statement is basically duplicated. It doesn't
> need to be treated as a special case. We could do something like below.
> I deliberately didn't delete the tabs. Also I haven't tested it.
Indeed! I looked at the history, and this function has been
structured with the duplication since sometime in 2010, which
pre-dates my involvement by several years. I don't know of
any reason why the duplication is needed, and agree it could
be eliminated.
Assuming Markus is OK with my proposal on the handling of
memory allocation failures, a single patch could simplify this
function quite a bit.
Dan -- do you want to create and submit the patch? I'll test the
code on Hyper-V. Or I can create, test, and submit the patch with
a "Suggested-by: Dan Carpenter".
Michael
>
> regards,
> dan carpenter
>
> diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c
> index 56f7e06c673e..2ba65f9ad3f1 100644
> --- a/drivers/hv/channel.c
> +++ b/drivers/hv/channel.c
> @@ -328,9 +328,9 @@ static int create_gpadl_header(enum hv_gpadl_type type, void *kbuffer,
> sizeof(struct gpa_range);
> pfncount = pfnsize / sizeof(u64);
>
> - if (pagecount > pfncount) {
> - /* we need a gpadl body */
> - /* fill in the header */
> + if (pagecount < pfncount)
> + pfncount = pagecount;
> +
> msgsize = sizeof(struct vmbus_channel_msginfo) +
> sizeof(struct vmbus_channel_gpadl_header) +
> sizeof(struct gpa_range) + pfncount * sizeof(u64);
> @@ -410,31 +410,6 @@ static int create_gpadl_header(enum hv_gpadl_type type, void *kbuffer,
> pfnsum += pfncurr;
> pfnleft -= pfncurr;
> }
> - } else {
> - /* everything fits in a header */
> - msgsize = sizeof(struct vmbus_channel_msginfo) +
> - sizeof(struct vmbus_channel_gpadl_header) +
> - sizeof(struct gpa_range) + pagecount * sizeof(u64);
> - msgheader = kzalloc(msgsize, GFP_KERNEL);
> - if (msgheader == NULL)
> - goto nomem;
> -
> - INIT_LIST_HEAD(&msgheader->submsglist);
> - msgheader->msgsize = msgsize;
> -
> - gpadl_header = (struct vmbus_channel_gpadl_header *)
> - msgheader->msg;
> - gpadl_header->rangecount = 1;
> - gpadl_header->range_buflen = sizeof(struct gpa_range) +
> - pagecount * sizeof(u64);
> - gpadl_header->range[0].byte_offset = 0;
> - gpadl_header->range[0].byte_count = hv_gpadl_size(type, size);
> - for (i = 0; i < pagecount; i++)
> - gpadl_header->range[0].pfn_array[i] = hv_gpadl_hvpfn(
> - type, kbuffer, size, send_offset, i);
> -
> - *msginfo = msgheader;
> - }
>
> return 0;
> nomem:
