drivers:hv: Allow for MMIO claims that span ACPI _CRS records

This patch makes 16GB GPUs work in Hyper-V VMs, since, for
compatibility reasons, the Hyper-V BIOS lists MMIO ranges in 2GB
chunks in its root bus's _CRS object.

Signed-off-by: Jake Oshins <jakeo@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Jake Oshins 2015-12-14 16:01:52 -08:00 committed by Greg Kroah-Hartman
parent d6f591e339
commit 40f26f3168

View file

@ -1063,12 +1063,28 @@ static acpi_status vmbus_walk_resources(struct acpi_resource *res, void *ctx)
new_res->start = start;
new_res->end = end;
/*
* Stick ranges from higher in address space at the front of the list.
* If two ranges are adjacent, merge them.
*/
do {
if (!*old_res) {
*old_res = new_res;
break;
}
if (((*old_res)->end + 1) == new_res->start) {
(*old_res)->end = new_res->end;
kfree(new_res);
break;
}
if ((*old_res)->start == new_res->end + 1) {
(*old_res)->start = new_res->start;
kfree(new_res);
break;
}
if ((*old_res)->end < new_res->start) {
new_res->sibling = *old_res;
if (prev_res)