if (shadow_pde_access == PT_ACCESS_NOT_PRESENT) {
- if (info->use_large_pages && guest_pde->large_page) {
+ if ((info->use_large_pages == 1) && (guest_pde->large_page == 1)) {
// Check underlying physical memory map to see if a large page is viable
- addr_t guest_pa = BASE_TO_PAGE_ADDR_4MB(((pde32_4MB_t *)guest_pde)->page_base_addr);
- addr_t host_pa;
- if (v3_get_max_page_size(info, guest_pa, PAGE_SIZE_4MB) < PAGE_SIZE_4MB) {
- PrintDebug("Underlying physical memory map doesn't allow use of a large page.\n");
- // Fallthrough to small pages
- } else if ((v3_gpa_to_hpa(info, guest_pa, &host_pa) != 0)
- || (v3_compute_page_alignment(host_pa) < PAGE_SIZE_4MB)) {
- PrintDebug("Host memory alignment doesn't allow use of a large page.\n");
- // Fallthrough to small pages
- } else if (handle_4MB_shadow_pagefault_pde_32(info, fault_addr, error_code, shadow_pde_access,
- (pde32_4MB_t *)shadow_pde, (pde32_4MB_t *)guest_pde) == 0) {
+ addr_t guest_pa = BASE_TO_PAGE_ADDR_4MB(((pde32_4MB_t *)guest_pde)->page_base_addr);
+ uint32_t page_size = v3_get_max_page_size(info, guest_pa, PROTECTED);
+
+ if (page_size == PAGE_SIZE_4MB) {
+ PrintError("using large page for fault_addr %p (gpa=%p)\n", (void *)fault_addr, (void *)guest_pa);
+ if (handle_4MB_shadow_pagefault_pde_32(info, fault_addr, error_code, shadow_pde_access,
+ (pde32_4MB_t *)shadow_pde, (pde32_4MB_t *)guest_pde) == -1) {
+ PrintError("Error handling large pagefault with large page\n");
+ return -1;
+ }
+
return 0;
- } else {
- PrintError("Error handling large pagefault with large page\n");
- return -1;
- }
- // Fallthrough to handle the region with small pages
+ }
}
struct shadow_page_data * shdw_page = create_new_shadow_pt(info);
}
}
-
// VMM Specific options
shadow_pde->write_through = guest_pde->write_through;
shadow_pde->cache_disable = guest_pde->cache_disable;
guest_pde->accessed = 1;
-
shadow_pde->pt_base_addr = PAGE_BASE_ADDR(shdw_page->page_pa);
} else {
shadow_pt = (pte32_t *)V3_VAddr((void *)BASE_TO_PAGE_ADDR(shadow_pde->pt_base_addr));
}
-
-
+
if (guest_pde->large_page == 0) {
if (v3_gpa_to_hva(info, BASE_TO_PAGE_ADDR(guest_pde->pt_base_addr), (addr_t*)&guest_pt) == -1) {
// Machine check the guest
return -1;
}
- PrintDebug("\tMapping shadow page (%p)\n", (void *)BASE_TO_PAGE_ADDR(shadow_pte->page_base_addr));
+ PrintError("shadow PA = %p\n", (void *)shadow_pa);
+
large_guest_pde->vmm_info = V3_LARGE_PG; /* For invalidations */
large_shadow_pde->page_base_addr = PAGE_BASE_ADDR_4MB(shadow_pa);
large_shadow_pde->present = 1;
large_shadow_pde->user_page = 1;
+ PrintDebug("\tMapping shadow page (%p)\n", (void *)BASE_TO_PAGE_ADDR_4MB(large_shadow_pde->page_base_addr));
+
if (shdw_reg->flags.write == 0) {
large_shadow_pde->writable = 0;
} else {
entry->host_addr = host_addr;
-
entry->flags.read = 1;
entry->flags.write = 1;
entry->flags.exec = 1;
static inline
struct v3_mem_region * __insert_mem_region(struct v3_vm_info * vm,
- struct v3_mem_region * region) {
+ struct v3_mem_region * region) {
struct rb_node ** p = &(vm->mem_map.mem_regions.rb_node);
struct rb_node * parent = NULL;
struct v3_mem_region * tmp_region;
-/* Given an address, find the successor region. If the address is within a region, return that
- * region. Input is an address, because the address may not have a region associated with it.
- *
- * Returns a region following or touching the given address. If address is invalid, NULL is
- * returned, else the base region is returned if no region exists at or after the given address.
+/* This returns the next memory region based on a given address.
+ * If the address falls inside a sub region, that region is returned.
+ * If the address falls outside a sub region, the next sub region is returned
+ * NOTE that we have to be careful about core_ids here...
*/
-struct v3_mem_region * v3_get_next_mem_region( struct v3_vm_info * vm, uint16_t core_id, addr_t guest_addr) {
- struct rb_node * current_n = vm->mem_map.mem_regions.rb_node;
- struct rb_node * successor_n = NULL; /* left-most node greater than guest_addr */
- struct v3_mem_region * current_r = NULL;
-
- /* current_n tries to find the region containing guest_addr, going right when smaller and left when
- * greater. Each time current_n becomes greater than guest_addr, update successor <- current_n.
- * current_n becomes successively closer to guest_addr than the previous time it was greater
- * than guest_addr.
- */
-
- /* | is address, ---- is region, + is intersection */
- while (current_n) {
- current_r = rb_entry(current_n, struct v3_mem_region, tree_node);
- if (current_r->guest_start > guest_addr) { /* | ---- */
- successor_n = current_n;
- current_n = current_n->rb_left;
+static struct v3_mem_region * get_next_mem_region( struct v3_vm_info * vm, uint16_t core_id, addr_t guest_addr) {
+ struct rb_node * n = vm->mem_map.mem_regions.rb_node;
+ struct v3_mem_region * reg = NULL;
+ struct v3_mem_region * parent = NULL;
+
+ while (n) {
+
+ reg = rb_entry(n, struct v3_mem_region, tree_node);
+
+ if (guest_addr < reg->guest_start) {
+ n = n->rb_left;
+ } else if (guest_addr >= reg->guest_end) {
+ n = n->rb_right;
} else {
- if (current_r->guest_end > guest_addr) {
- return current_r; /* +--- or --+- */
+ if (reg->core_id == V3_MEM_CORE_ANY) {
+ // found relevant region, it's available on all cores
+ return reg;
+ } else if (core_id == reg->core_id) {
+ // found relevant region, it's available on the indicated core
+ return reg;
+ } else if (core_id < reg->core_id) {
+ // go left, core too big
+ n = n->rb_left;
+ } else if (core_id > reg->core_id) {
+ // go right, core too small
+ n = n->rb_right;
+ } else {
+ PrintError("v3_get_mem_region: Impossible!\n");
+ return NULL;
}
- current_n = current_n->rb_right; /* ---- | */
+ }
+
+ if ((reg->core_id == core_id) || (reg->core_id == V3_MEM_CORE_ANY)) {
+ parent = reg;
}
}
- /* Address does not have its own region. Check if it's a valid address in the base region */
- if (guest_addr >= vm->mem_map.base_region.guest_end) {
- PrintError("%s: Guest Address Exceeds Base Memory Size (ga=%p), (limit=%p)\n",
- __FUNCTION__, (void *)guest_addr, (void *)vm->mem_map.base_region.guest_end);
- v3_print_mem_map(vm);
- return NULL;
+ if (parent->guest_start > guest_addr) {
+ return parent;
+ } else if (parent->guest_end < guest_addr) {
+ struct rb_node * node = &(parent->tree_node);
+
+ while ((node = v3_rb_next(node)) != NULL) {
+ struct v3_mem_region * next_reg = rb_entry(node, struct v3_mem_region, tree_node);
+
+ if ((next_reg->core_id == V3_MEM_CORE_ANY) ||
+ (next_reg->core_id == core_id)) {
+
+ // This check is not strictly necessary, but it makes it clearer
+ if (next_reg->guest_start > guest_addr) {
+ return next_reg;
+ }
+ }
+ }
}
- return &(vm->mem_map.base_region);
+ return NULL;
}
+/* Given an address region of memory, find if there are any regions that overlap with it.
+ * This checks that the range lies in a single region, and returns that region if it does,
+ * this can be either the base region or a sub region.
+ * IF there are multiple regions in the range then it returns NULL
+ */
+static struct v3_mem_region * get_overlapping_region(struct v3_vm_info * vm, uint16_t core_id,
+ addr_t start_gpa, addr_t end_gpa) {
+ struct v3_mem_region * start_region = v3_get_mem_region(vm, core_id, start_gpa);
+
+ if (start_region == NULL) {
+ PrintError("Invalid memory region\n");
+ return NULL;
+ }
+
+
+ if (start_region->guest_end < end_gpa) {
+ // Region ends before range
+ return NULL;
+ } else if (start_region->flags.base == 0) {
+ // sub region overlaps range
+ return start_region;
+ } else {
+ // Base region, now we have to scan forward for the next sub region
+ struct v3_mem_region * next_reg = get_next_mem_region(vm, core_id, start_gpa);
+
+ if (next_reg == NULL) {
+ // no sub regions after start_addr, base region is ok
+ return start_region;
+ } else if (next_reg->guest_start >= end_gpa) {
+ // Next sub region begins outside range
+ return start_region;
+ } else {
+ return NULL;
+ }
+ }
+
+
+ // Should never get here
+ return NULL;
+}
+
+
+
+
+
void v3_delete_mem_region(struct v3_vm_info * vm, struct v3_mem_region * reg) {
int i = 0;
}
// Determine if a given address can be handled by a large page of the requested size
-uint32_t v3_get_max_page_size(struct guest_info * core, addr_t fault_addr, uint32_t req_size) {
- addr_t pg_start = 0UL, pg_end = 0UL; // large page containing the faulting addres
- struct v3_mem_region * pg_next_reg = NULL; // next immediate mem reg after page start addr
+uint32_t v3_get_max_page_size(struct guest_info * core, addr_t page_addr, v3_cpu_mode_t mode) {
+ addr_t pg_start = 0;
+ addr_t pg_end = 0;
uint32_t page_size = PAGE_SIZE_4KB;
+ struct v3_mem_region * reg = NULL;
- /* If the guest has been configured for large pages, then we must check for hooked regions of
- * memory which may overlap with the large page containing the faulting address (due to
- * potentially differing access policies in place for e.g. i/o devices and APIC). A large page
- * can be used if a) no region overlaps the page [or b) a region does overlap but fully contains
- * the page]. The [bracketed] text pertains to the #if 0'd code below, state D. TODO modify this
- * note if someone decides to enable this optimization. It can be tested with the SeaStar
- * mapping.
- *
- * Examples: (CAPS regions are returned by v3_get_next_mem_region; state A returns the base reg)
- *
- * |region| |region| 2MiB mapped (state A)
- * |reg| |REG| 2MiB mapped (state B)
- * |region| |reg| |REG| |region| |reg| 4KiB mapped (state C)
- * |reg| |reg| |--REGION---| [2MiB mapped (state D)]
- * |--------------------------------------------| RAM
- * ^ fault addr
- * |----|----|----|----|----|page|----|----|----| 2MB pages
- * >>>>>>>>>>>>>>>>>>>> search space
- */
-
-
- // guest page maps to a host page + offset (so when we shift, it aligns with a host page)
- switch (req_size) {
- case PAGE_SIZE_4KB:
- return PAGE_SIZE_4KB;
- case PAGE_SIZE_2MB:
- pg_start = PAGE_ADDR_2MB(fault_addr);
- pg_end = (pg_start + PAGE_SIZE_2MB);
- break;
- case PAGE_SIZE_4MB:
- pg_start = PAGE_ADDR_4MB(fault_addr);
- pg_end = (pg_start + PAGE_SIZE_4MB);
- break;
- case PAGE_SIZE_1GB:
- pg_start = PAGE_ADDR_1GB(fault_addr);
- pg_end = (pg_start + PAGE_SIZE_1GB);
- break;
- default:
- PrintError("Invalid large page size requested.\n");
- return -1;
- }
-
- //PrintDebug("%s: page [%p,%p) contains address\n", __FUNCTION__, (void *)pg_start, (void *)pg_end);
- pg_next_reg = v3_get_next_mem_region(core->vm_info, core->cpu_id, pg_start);
+ PrintError("Getting max page size for addr %p\n", (void *)page_addr);
+
+ switch (mode) {
+ case PROTECTED:
+ if (core->use_large_pages == 1) {
+ pg_start = PAGE_ADDR_4MB(page_addr);
+ pg_end = (pg_start + PAGE_SIZE_4MB);
- if (pg_next_reg == NULL) {
- PrintError("%s: Error: address not in base region, %p\n", __FUNCTION__, (void *)fault_addr);
- return PAGE_SIZE_4KB;
- }
+ reg = get_overlapping_region(core->vm_info, core->cpu_id, pg_start, pg_end);
- if (pg_next_reg->flags.base == 1) {
- page_size = req_size; // State A
- //PrintDebug("%s: base region [%p,%p) contains page.\n", __FUNCTION__,
- // (void *)pg_next_reg->guest_start, (void *)pg_next_reg->guest_end);
- } else {
-#if 0 // State B/C and D optimization
- if ((pg_next_reg->guest_end >= pg_end) &&
- ((pg_next_reg->guest_start >= pg_end) || (pg_next_reg->guest_start <= pg_start))) {
- page_size = req_size;
- }
+ if ((reg) && ((reg->host_addr % PAGE_SIZE_4MB) == 0)) {
+ page_size = PAGE_SIZE_4MB;
+ }
+ }
+ break;
+ case PROTECTED_PAE:
+ if (core->use_large_pages == 1) {
+ pg_start = PAGE_ADDR_2MB(page_addr);
+ pg_end = (pg_start + PAGE_SIZE_2MB);
- PrintDebug("%s: region [%p,%p) %s partially overlap with page\n", __FUNCTION__,
- (void *)pg_next_reg->guest_start, (void *)pg_next_reg->guest_end,
- (page_size == req_size) ? "does not" : "does");
+ reg = get_overlapping_region(core->vm_info, core->cpu_id, pg_start, pg_end);
-#else // State B/C
- if (pg_next_reg->guest_start >= pg_end) {
-
- page_size = req_size;
- }
+ if ((reg) && ((reg->host_addr % PAGE_SIZE_2MB) == 0)) {
+ page_size = PAGE_SIZE_2MB;
+ }
+ }
+ break;
+ case LONG:
+ case LONG_32_COMPAT:
+ case LONG_16_COMPAT:
+ if (core->use_giant_pages == 1) {
+ pg_start = PAGE_ADDR_1GB(page_addr);
+ pg_end = (pg_start + PAGE_SIZE_1GB);
+
+ reg = get_overlapping_region(core->vm_info, core->cpu_id, pg_start, pg_end);
+
+ if ((reg) && ((reg->host_addr % PAGE_SIZE_1GB) == 0)) {
+ page_size = PAGE_SIZE_1GB;
+ break;
+ }
+ }
- PrintDebug("%s: region [%p,%p) %s overlap with page\n", __FUNCTION__,
- (void *)pg_next_reg->guest_start, (void *)pg_next_reg->guest_end,
- (page_size == req_size) ? "does not" : "does");
+ if (core->use_large_pages == 1) {
+ pg_start = PAGE_ADDR_2MB(page_addr);
+ pg_end = (pg_start + PAGE_SIZE_2MB);
-#endif
+ reg = get_overlapping_region(core->vm_info, core->cpu_id, pg_start, pg_end);
+
+ if ((reg) && ((reg->host_addr % PAGE_SIZE_2MB) == 0)) {
+ page_size = PAGE_SIZE_2MB;
+ }
+ }
+ break;
+ default:
+ PrintError("Invalid CPU mode: %s\n", v3_cpu_mode_to_str(v3_get_vm_cpu_mode(core)));
+ return -1;
}
+
+ PrintError("Returning PAGE size = %d\n", page_size);
return page_size;
}
-// For an address on a page of size page_size, compute the actual alignment
-// of the physical page it maps to
-uint32_t v3_compute_page_alignment(addr_t page_addr)
-{
- if (PAGE_OFFSET_1GB(page_addr) == 0) {
- return PAGE_SIZE_1GB;
- } else if (PAGE_OFFSET_4MB(page_addr) == 0) {
- return PAGE_SIZE_4MB;
- } else if (PAGE_OFFSET_2MB(page_addr) == 0) {
- return PAGE_SIZE_2MB;
- } else if (PAGE_OFFSET_4KB(page_addr) == 0) {
- return PAGE_SIZE_4KB;
- } else {
- PrintError("Non-page aligned address passed to %s.\n", __FUNCTION__);
- return 0;
- }
-}
+
void v3_print_mem_map(struct v3_vm_info * vm) {
struct rb_node * node = v3_rb_first(&(vm->mem_map.mem_regions));
