return 0;
}
-// For an address on a page of size page_size, compute the actual alignment
-// of the physical page it maps to
-int compute_physical_alignment(addr_t va, addr_t pa, uint32_t page_size)
-{
- addr_t va_offset, pa_base;
- switch (page_size) {
- case PAGE_SIZE_1GB:
- va_offset = PAGE_OFFSET_1GB(va);
- break;
- case PAGE_SIZE_4MB:
- va_offset = PAGE_OFFSET_4MB(va);
- break;
- case PAGE_SIZE_2MB:
- va_offset = PAGE_OFFSET_2MB(va);
- break;
- case PAGE_SIZE_4KB:
- return 1;
- default:
- PrintError("Invalid page size in %s.\n", __FUNCTION__);
- return 0;
- }
-
- pa_base = pa - va_offset;
-
- if (PAGE_OFFSET_1GB(pa_base) == 0) {
- return PAGE_SIZE_1GB;
- } else if (PAGE_OFFSET_4MB(pa_base) == 0) {
- return PAGE_SIZE_4MB;
- } else if (PAGE_OFFSET_2MB(pa_base) == 0) {
- return PAGE_SIZE_2MB;
- } else if (PAGE_OFFSET_4KB(pa_base) == 0) {
- return PAGE_SIZE_4KB;
- } else {
- PrintError("Incorrection alignment setup or calculation in %s.\n", __FUNCTION__);
- return 0;
- }
-}
-
static int handle_pde_shadow_pagefault_64(struct guest_info * info, addr_t fault_addr, pf_error_t error_code,
pde64_t * shadow_pd, pde64_t * guest_pd) {
pt_access_status_t guest_pde_access;
if (shadow_pde_access == PT_ACCESS_NOT_PRESENT) {
// Check if we can use large pages and the guest memory is properly aligned
// to potentially use a large page
- if (info->use_large_pages && guest_pde->large_page) {
- // Check underlying physical memory map to see if a large page is viable
+
+ if ((info->use_large_pages == 1) && (guest_pde->large_page == 1)) {
addr_t guest_pa = BASE_TO_PAGE_ADDR_2MB(((pde64_2MB_t *)guest_pde)->page_base_addr);
- if ((compute_physical_alignment(fault_addr, guest_pa, PAGE_SIZE_2MB) >= PAGE_SIZE_2MB)
- && (v3_get_max_page_size(info, guest_pa, PAGE_SIZE_2MB) >= PAGE_SIZE_2MB)) {
- // should be able to use a large page.
- if (handle_2MB_shadow_pagefault_pde_64(info, fault_addr, error_code, shadow_pde_access,
- (pde64_2MB_t *)shadow_pde, (pde64_2MB_t *)guest_pde) == 0) {
- return 0;
- } else {
- PrintError("Error handling large pagefault with large page\n");
- return -1;
+ uint32_t page_size = v3_get_max_page_size(info, guest_pa, LONG);
+
+ if (page_size == PAGE_SIZE_2MB) {
+ if (handle_2MB_shadow_pagefault_pde_64(info, fault_addr, error_code, shadow_pde_access,
+ (pde64_2MB_t *)shadow_pde, (pde64_2MB_t *)guest_pde) == -1) {
+ PrintError("Error handling large pagefault with large page\n");
+ return -1;
}
- } else {
- PrintDebug("Alignment or underlying physical memory map doesn't allow use of a large page.\n");
+
+ return 0;
}
// Fallthrough to handle the region with small pages
}
shadow_pde->present = 1;
shadow_pde->user_page = guest_pde->user_page;
-
if (guest_pde->large_page == 0) {
shadow_pde->writable = guest_pde->writable;
} else {