iommu/amd: Optimize iommu_unmap_page for new fetch_pte interface

Now that fetch_pte returns the page-size of the pte, this
function can be optimized a lot.

Tested-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This commit is contained in:
Joerg Roedel 2015-04-01 14:58:49 +02:00
parent 3039ca1b1c
commit 71b390e9be

View File

@ -1428,8 +1428,8 @@ static unsigned long iommu_unmap_page(struct protection_domain *dom,
unsigned long bus_addr,
unsigned long page_size)
{
unsigned long long unmap_size, unmapped;
unsigned long pte_pgsize;
unsigned long long unmapped;
unsigned long unmap_size;
u64 *pte;
BUG_ON(!is_power_of_2(page_size));
@ -1438,28 +1438,12 @@ static unsigned long iommu_unmap_page(struct protection_domain *dom,
while (unmapped < page_size) {
pte = fetch_pte(dom, bus_addr, &pte_pgsize);
pte = fetch_pte(dom, bus_addr, &unmap_size);
if (!pte) {
/*
* No PTE for this address
* move forward in 4kb steps
*/
unmap_size = PAGE_SIZE;
} else if (PM_PTE_LEVEL(*pte) == 0) {
/* 4kb PTE found for this address */
unmap_size = PAGE_SIZE;
*pte = 0ULL;
} else {
int count, i;
if (pte) {
int i, count;
/* Large PTE found which maps this address */
unmap_size = PTE_PAGE_SIZE(*pte);
/* Only unmap from the first pte in the page */
if ((unmap_size - 1) & bus_addr)
break;
count = PAGE_SIZE_PTE_COUNT(unmap_size);
count = PAGE_SIZE_PTE_COUNT(unmap_size);
for (i = 0; i < count; i++)
pte[i] = 0ULL;
}