+/*
+ * This file is part of the Palacios Virtual Machine Monitor developed
+ * by the V3VEE Project with funding from the United States National
+ * Science Foundation and the Department of Energy.
+ *
+ * The V3VEE Project is a joint project between Northwestern University
+ * and the University of New Mexico. You can find out more at
+ * http://www.v3vee.org
+ *
+ * Copyright (c) 2008, Jack Lange <jarusl@cs.northwestern.edu>
+ * Copyright (c) 2008, The V3VEE Project <http://www.v3vee.org>
+ * All rights reserved.
+ *
+ * Author: Jack Lange <jarusl@cs.northwestern.edu>
+ *
+ * This is free software. You are permitted to use,
+ * redistribute, and modify it as specified in the file "V3VEE_LICENSE".
+ */
+
+
#include <palacios/vmm_shadow_paging.h>
#include <palacios/vmm.h>
#include <palacios/vm_guest_mem.h>
#include <palacios/vmm_decoder.h>
+#include <palacios/vmm_ctrl_regs.h>
+
+#include <palacios/vmm_hashtable.h>
-#ifndef DEBUG_SHADOW_PAGING
+#include <palacios/vmm_direct_paging.h>
+
+
+#ifdef CONFIG_SHADOW_PAGING_TELEMETRY
+#include <palacios/vmm_telemetry.h>
+#endif
+
+#ifdef CONFIG_SYMBIOTIC_SWAP
+#include <palacios/vmm_sym_swap.h>
+#endif
+
+#ifndef CONFIG_DEBUG_SHADOW_PAGING
#undef PrintDebug
#define PrintDebug(fmt, args...)
#endif
***/
-
-
-static int handle_shadow_pte32_fault(struct guest_info* info,
- addr_t fault_addr,
- pf_error_t error_code,
- pte32_t * shadow_pte,
- pte32_t * guest_pte);
-
-static int handle_shadow_pagefault32(struct guest_info * info, addr_t fault_addr, pf_error_t error_code);
-
-int init_shadow_page_state(struct guest_info * info) {
- struct shadow_page_state * state = &(info->shdw_pg_state);
- state->guest_mode = PDE32;
- state->shadow_mode = PDE32;
+struct shadow_page_data {
+ v3_reg_t cr3;
+ addr_t page_pa;
- state->guest_cr3 = 0;
- state->shadow_cr3 = 0;
+ struct list_head page_list_node;
+};
- return 0;
-}
-int handle_shadow_pagefault(struct guest_info * info, addr_t fault_addr, pf_error_t error_code) {
-
- if (info->mem_mode == PHYSICAL_MEM) {
- // If paging is not turned on we need to handle the special cases
- return handle_special_page_fault(info, fault_addr, fault_addr, error_code);
- } else if (info->mem_mode == VIRTUAL_MEM) {
-
- switch (info->cpu_mode) {
- case PROTECTED:
- return handle_shadow_pagefault32(info, fault_addr, error_code);
- break;
- case PROTECTED_PAE:
- case LONG:
- default:
- PrintError("Unhandled CPU Mode\n");
- return -1;
- }
- } else {
- PrintError("Invalid Memory mode\n");
- return -1;
- }
-}
-addr_t create_new_shadow_pt32() {
- void * host_pde = 0;
+static struct shadow_page_data * create_new_shadow_pt(struct guest_info * info);
+static int inject_guest_pf(struct guest_info * info, addr_t fault_addr, pf_error_t error_code);
+static int is_guest_pf(pt_access_status_t guest_access, pt_access_status_t shadow_access);
- host_pde = V3_AllocPages(1);
- memset(host_pde, 0, PAGE_SIZE);
- return (addr_t)host_pde;
-}
-
-
-static void inject_guest_pf(struct guest_info * info, addr_t fault_addr, pf_error_t error_code) {
- info->ctrl_regs.cr2 = fault_addr;
- v3_raise_exception_with_error(info, PF_EXCEPTION, *(uint_t *)&error_code);
-}
-
-
-static int is_guest_pf(pt_access_status_t guest_access, pt_access_status_t shadow_access) {
- /* basically the reasoning is that there can be multiple reasons for a page fault:
- If there is a permissions failure for a page present in the guest _BUT_
- the reason for the fault was that the page is not present in the shadow,
- _THEN_ we have to map the shadow page in and reexecute, this will generate
- a permissions fault which is _THEN_ valid to send to the guest
- _UNLESS_ both the guest and shadow have marked the page as not present
-
- whew...
- */
- if (guest_access != PT_ACCESS_OK) {
- // Guest Access Error
-
- if ((shadow_access != PT_ENTRY_NOT_PRESENT) &&
- (guest_access != PT_ENTRY_NOT_PRESENT)) {
- // aka (guest permission error)
- return 1;
- }
+#include "vmm_shadow_paging_32.h"
+#include "vmm_shadow_paging_32pae.h"
+#include "vmm_shadow_paging_64.h"
- if ((shadow_access == PT_ENTRY_NOT_PRESENT) &&
- (guest_access == PT_ENTRY_NOT_PRESENT)) {
- // Page tables completely blank, handle guest first
- return 1;
- }
- // Otherwise we'll handle the guest fault later...?
- }
- return 0;
+#ifdef CONFIG_SHADOW_PAGING_TELEMETRY
+static void telemetry_cb(struct guest_info * info, void * private_data, char * hdr) {
+ V3_Print("%s Guest Page faults: %d\n", hdr, info->shdw_pg_state.guest_faults);
}
+#endif
-
-/* The guest status checks have already been done,
- * only special case shadow checks remain
- */
-static int handle_large_pagefault32(struct guest_info * info,
- addr_t fault_addr, pf_error_t error_code,
- pte32_t * shadow_pt, pde32_4MB_t * large_guest_pde)
-{
- pt_access_status_t shadow_pte_access = can_access_pte32(shadow_pt, fault_addr, error_code);
- pte32_t * shadow_pte = (pte32_t *)&(shadow_pt[PTE32_INDEX(fault_addr)]);
+int v3_init_shadow_page_state(struct guest_info * info) {
+ struct shadow_page_state * state = &(info->shdw_pg_state);
- if (shadow_pte_access == PT_ACCESS_OK) {
- // Inconsistent state...
- // Guest Re-Entry will flush tables and everything should now workd
- PrintDebug("Inconsistent state... Guest re-entry should flush tlb\n");
- return 0;
- }
-
-
- if (shadow_pte_access == PT_ENTRY_NOT_PRESENT) {
- // Get the guest physical address of the fault
- addr_t guest_fault_pa = PDE32_4MB_T_ADDR(*large_guest_pde) + PD32_4MB_PAGE_OFFSET(fault_addr);
- host_region_type_t host_page_type = get_shadow_addr_type(info, guest_fault_pa);
-
-
- if (host_page_type == HOST_REGION_INVALID) {
- // Inject a machine check in the guest
- PrintDebug("Invalid Guest Address in page table (0x%x)\n", guest_fault_pa);
- v3_raise_exception(info, MC_EXCEPTION);
- return 0;
- }
-
- if (host_page_type == HOST_REGION_PHYSICAL_MEMORY) {
- addr_t shadow_pa = get_shadow_addr(info, guest_fault_pa);
+ state->guest_cr3 = 0;
+ state->guest_cr0 = 0;
+ state->guest_efer.value = 0x0LL;
- shadow_pte->page_base_addr = PT32_BASE_ADDR(shadow_pa);
+ INIT_LIST_HEAD(&(state->page_list));
- shadow_pte->present = 1;
-
- /* We are assuming that the PDE entry has precedence
- * so the Shadow PDE will mirror the guest PDE settings,
- * and we don't have to worry about them here
- * Allow everything
- */
- shadow_pte->user_page = 1;
- shadow_pte->writable = 1;
-
- //set according to VMM policy
- shadow_pte->write_through = 0;
- shadow_pte->cache_disable = 0;
- shadow_pte->global_page = 0;
- //
-
- } else {
- // Handle hooked pages as well as other special pages
- if (handle_special_page_fault(info, fault_addr, PT32_PAGE_ADDR(guest_fault_pa), error_code) == -1) {
- PrintError("Special Page Fault handler returned error for address: %x\n", fault_addr);
- return -1;
- }
+#ifdef CONFIG_SHADOW_PAGING_TELEMETRY
+ if (info->enable_telemetry) {
+ v3_add_telemetry_cb(info, telemetry_cb, NULL);
}
- } else {
- PrintError("Error in large page fault handler...\n");
- PrintError("This case should have been handled at the top level handler\n");
- return -1;
- }
-
- PrintDebug("Returning from large page fault handler\n");
- return 0;
-}
-
-
-static int handle_shadow_pagefault32(struct guest_info * info, addr_t fault_addr, pf_error_t error_code) {
- pde32_t * guest_pd = NULL;
- pde32_t * shadow_pd = (pde32_t *)CR3_TO_PDE32(info->shdw_pg_state.shadow_cr3);
- addr_t guest_cr3 = CR3_TO_PDE32(info->shdw_pg_state.guest_cr3);
- pt_access_status_t guest_pde_access;
- pt_access_status_t shadow_pde_access;
- pde32_t * guest_pde = NULL;
- pde32_t * shadow_pde = (pde32_t *)&(shadow_pd[PDE32_INDEX(fault_addr)]);
-
- PrintDebug("Shadow page fault handler\n");
-
- if (guest_pa_to_host_va(info, guest_cr3, (addr_t*)&guest_pd) == -1) {
- PrintError("Invalid Guest PDE Address: 0x%x\n", guest_cr3);
- return -1;
- }
-
- guest_pde = (pde32_t *)&(guest_pd[PDE32_INDEX(fault_addr)]);
-
-
- // Check the guest page permissions
- guest_pde_access = can_access_pde32(guest_pd, fault_addr, error_code);
-
- // Check the shadow page permissions
- shadow_pde_access = can_access_pde32(shadow_pd, fault_addr, error_code);
+#endif
- /* Was the page fault caused by the Guest's page tables? */
- if (is_guest_pf(guest_pde_access, shadow_pde_access) == 1) {
- PrintDebug("Injecting PDE pf to guest: (guest access error=%d) (pf error code=%d)\n",
- guest_pde_access, error_code);
- inject_guest_pf(info, fault_addr, error_code);
return 0;
- }
-
-
- if (shadow_pde_access == PT_ENTRY_NOT_PRESENT)
- {
- pte32_t * shadow_pt = (pte32_t *)create_new_shadow_pt32();
-
- shadow_pde->present = 1;
- shadow_pde->user_page = guest_pde->user_page;
- // shadow_pde->large_page = guest_pde->large_page;
- shadow_pde->large_page = 0;
-
-
- // VMM Specific options
- shadow_pde->write_through = 0;
- shadow_pde->cache_disable = 0;
- shadow_pde->global_page = 0;
- //
-
- guest_pde->accessed = 1;
-
- shadow_pde->pt_base_addr = PD32_BASE_ADDR(shadow_pt);
-
- if (guest_pde->large_page == 0) {
- shadow_pde->writable = guest_pde->writable;
- } else {
- ((pde32_4MB_t *)guest_pde)->dirty = 0;
- shadow_pde->writable = 0;
- }
- }
- else if (shadow_pde_access == PT_ACCESS_OK)
- {
- //
- // PTE fault
- //
- pte32_t * shadow_pt = (pte32_t *)PDE32_T_ADDR((*shadow_pde));
-
- if (guest_pde->large_page == 0) {
- pte32_t * guest_pt = NULL;
- if (guest_pa_to_host_va(info, PDE32_T_ADDR((*guest_pde)), (addr_t*)&guest_pt) == -1) {
- // Machine check the guest
- PrintDebug("Invalid Guest PTE Address: 0x%x\n", PDE32_T_ADDR((*guest_pde)));
- v3_raise_exception(info, MC_EXCEPTION);
- return 0;
- }
-
- if (handle_shadow_pte32_fault(info, fault_addr, error_code, shadow_pt, guest_pt) == -1) {
- PrintError("Error handling Page fault caused by PTE\n");
- return -1;
- }
- } else if (guest_pde->large_page == 1) {
- if (handle_large_pagefault32(info, fault_addr, error_code, shadow_pt, (pde32_4MB_t *)guest_pde) == -1) {
- PrintError("Error handling large pagefault\n");
- return -1;
- }
- }
- }
- else if ((shadow_pde_access == PT_WRITE_ERROR) &&
- (guest_pde->large_page == 1) &&
- (((pde32_4MB_t *)guest_pde)->dirty == 0))
- {
- //
- // Page Directory Entry marked read-only
- // Its a large page and we need to update the dirty bit in the guest
- //
- PrintDebug("Large page write error... Setting dirty bit and returning\n");
- ((pde32_4MB_t *)guest_pde)->dirty = 1;
- shadow_pde->writable = guest_pde->writable;
- return 0;
-
- }
- else if (shadow_pde_access == PT_USER_ERROR)
- {
- //
- // Page Directory Entry marked non-user
- //
- PrintDebug("Shadow Paging User access error (shadow_pde_access=0x%x, guest_pde_access=0x%x)\n",
- shadow_pde_access, guest_pde_access);
- inject_guest_pf(info, fault_addr, error_code);
- return 0;
- }
- else
- {
- // inject page fault in guest
- inject_guest_pf(info, fault_addr, error_code);
- PrintDebug("Unknown Error occurred (shadow_pde_access=%d)\n", shadow_pde_access);
- PrintDebug("Manual Says to inject page fault into guest\n");
-#ifdef DEBUG_SHADOW_PAGING
- PrintDebug("Guest PDE: (access=%d)\n\t", guest_pde_access);
- PrintPDE32(fault_addr, guest_pde);
- PrintDebug("Shadow PDE: (access=%d)\n\t", shadow_pde_access);
- PrintPDE32(fault_addr, shadow_pde);
-#endif
-
- return 0;
- }
-
- PrintDebug("Returning end of PDE function (rip=%x)\n", info->rip);
- return 0;
}
-/*
- * We assume the the guest pte pointer has already been translated to a host virtual address
- */
-static int handle_shadow_pte32_fault(struct guest_info * info,
- addr_t fault_addr,
- pf_error_t error_code,
- pte32_t * shadow_pt,
- pte32_t * guest_pt) {
-
- pt_access_status_t guest_pte_access;
- pt_access_status_t shadow_pte_access;
- pte32_t * guest_pte = (pte32_t *)&(guest_pt[PTE32_INDEX(fault_addr)]);;
- pte32_t * shadow_pte = (pte32_t *)&(shadow_pt[PTE32_INDEX(fault_addr)]);
-
-
- // Check the guest page permissions
- guest_pte_access = can_access_pte32(guest_pt, fault_addr, error_code);
+// Reads the guest CR3 register
+// creates new shadow page tables
+// updates the shadow CR3 register to point to the new pts
+int v3_activate_shadow_pt(struct guest_info * info) {
+ switch (v3_get_vm_cpu_mode(info)) {
+
+ case PROTECTED:
+ return activate_shadow_pt_32(info);
+ case PROTECTED_PAE:
+ return activate_shadow_pt_32pae(info);
+ case LONG:
+ case LONG_32_COMPAT:
+ case LONG_16_COMPAT:
+ return activate_shadow_pt_64(info);
+ default:
+ PrintError("Invalid CPU mode: %s\n", v3_cpu_mode_to_str(v3_get_vm_cpu_mode(info)));
+ return -1;
+ }
- // Check the shadow page permissions
- shadow_pte_access = can_access_pte32(shadow_pt, fault_addr, error_code);
-
-#ifdef DEBUG_SHADOW_PAGING
- PrintDebug("Guest PTE: (access=%d)\n\t", guest_pte_access);
- PrintPTE32(fault_addr, guest_pte);
- PrintDebug("Shadow PTE: (access=%d)\n\t", shadow_pte_access);
- PrintPTE32(fault_addr, shadow_pte);
-#endif
-
- /* Was the page fault caused by the Guest's page tables? */
- if (is_guest_pf(guest_pte_access, shadow_pte_access) == 1) {
- PrintDebug("Access error injecting pf to guest (guest access error=%d) (pf error code=%d)\n",
- guest_pte_access, *(uint_t*)&error_code);
- inject_guest_pf(info, fault_addr, error_code);
- return 0;
- }
-
-
- if (shadow_pte_access == PT_ACCESS_OK) {
- // Inconsistent state...
- // Guest Re-Entry will flush page tables and everything should now work
- PrintDebug("Inconsistent state... Guest re-entry should flush tlb\n");
return 0;
- }
-
-
- if (shadow_pte_access == PT_ENTRY_NOT_PRESENT) {
+}
- addr_t guest_pa = PTE32_T_ADDR((*guest_pte));
- // Page Table Entry Not Present
- host_region_type_t host_page_type = get_shadow_addr_type(info, guest_pa);
+// This must flush any caches
+// and reset the cr3 value to the correct value
+int v3_invalidate_shadow_pts(struct guest_info * info) {
+ return v3_activate_shadow_pt(info);
+}
- if (host_page_type == HOST_REGION_INVALID) {
- // Inject a machine check in the guest
- PrintDebug("Invalid Guest Address in page table (0x%x)\n", guest_pa);
- v3_raise_exception(info, MC_EXCEPTION);
- return 0;
- }
- // else...
-
- if (host_page_type == HOST_REGION_PHYSICAL_MEMORY) {
- addr_t shadow_pa = get_shadow_addr(info, guest_pa);
-
- shadow_pte->page_base_addr = PT32_BASE_ADDR(shadow_pa);
-
- shadow_pte->present = guest_pte->present;
- shadow_pte->user_page = guest_pte->user_page;
-
- //set according to VMM policy
- shadow_pte->write_through = 0;
- shadow_pte->cache_disable = 0;
- shadow_pte->global_page = 0;
- //
-
- guest_pte->accessed = 1;
-
- if (guest_pte->dirty == 1) {
- shadow_pte->writable = guest_pte->writable;
- } else if ((guest_pte->dirty == 0) && (error_code.write == 1)) {
- shadow_pte->writable = guest_pte->writable;
- guest_pte->dirty = 1;
- } else if ((guest_pte->dirty = 0) && (error_code.write == 0)) {
- shadow_pte->writable = 0;
- }
+int v3_handle_shadow_pagefault(struct guest_info * info, addr_t fault_addr, pf_error_t error_code) {
+
+ if (v3_get_vm_mem_mode(info) == PHYSICAL_MEM) {
+ // If paging is not turned on we need to handle the special cases
+ return v3_handle_passthrough_pagefault(info, fault_addr, error_code);
+ } else if (v3_get_vm_mem_mode(info) == VIRTUAL_MEM) {
+
+ switch (v3_get_vm_cpu_mode(info)) {
+ case PROTECTED:
+ return handle_shadow_pagefault_32(info, fault_addr, error_code);
+ break;
+ case PROTECTED_PAE:
+ return handle_shadow_pagefault_32pae(info, fault_addr, error_code);
+ case LONG:
+ case LONG_32_COMPAT:
+ case LONG_16_COMPAT:
+ return handle_shadow_pagefault_64(info, fault_addr, error_code);
+ break;
+ default:
+ PrintError("Unhandled CPU Mode: %s\n", v3_cpu_mode_to_str(v3_get_vm_cpu_mode(info)));
+ return -1;
+ }
} else {
- // Page fault handled by hook functions
- if (handle_special_page_fault(info, fault_addr, guest_pa, error_code) == -1) {
- PrintError("Special Page fault handler returned error for address: %x\n", fault_addr);
+ PrintError("Invalid Memory mode\n");
return -1;
- }
}
-
- } else if ((shadow_pte_access == PT_WRITE_ERROR) &&
- (guest_pte->dirty == 0)) {
-
- PrintDebug("Shadow PTE Write Error\n");
- guest_pte->dirty = 1;
- shadow_pte->writable = guest_pte->writable;
- return 0;
-
- } else {
- // Inject page fault into the guest
- inject_guest_pf(info, fault_addr, error_code);
- PrintError("PTE Page fault fell through... Not sure if this should ever happen\n");
- PrintError("Manual Says to inject page fault into guest\n");
- return -1;
- }
-
- PrintDebug("Returning end of function\n");
- return 0;
}
+int v3_handle_shadow_invlpg(struct guest_info * info) {
+ uchar_t instr[15];
+ struct x86_instr dec_instr;
+ int ret = 0;
+ addr_t vaddr = 0;
-
-
-
-/* Currently Does not work with Segmentation!!! */
-int handle_shadow_invlpg(struct guest_info * info) {
- if (info->mem_mode != VIRTUAL_MEM) {
- // Paging must be turned on...
- // should handle with some sort of fault I think
- PrintError("ERROR: INVLPG called in non paged mode\n");
- return -1;
- }
-
-
- if (info->cpu_mode == PROTECTED) {
- char instr[15];
- int ret;
- int index = 0;
-
- ret = read_guest_va_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr);
- if (ret != 15) {
- PrintError("Could not read instruction 0x%x (ret=%d)\n", info->rip, ret);
- return -1;
+ if (v3_get_vm_mem_mode(info) != VIRTUAL_MEM) {
+ // Paging must be turned on...
+ // should handle with some sort of fault I think
+ PrintError("ERROR: INVLPG called in non paged mode\n");
+ return -1;
}
-
- /* Can INVLPG work with Segments?? */
- while (is_prefix_byte(instr[index])) {
- index++;
+ if (v3_get_vm_mem_mode(info) == PHYSICAL_MEM) {
+ ret = read_guest_pa_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr);
+ } else {
+ ret = read_guest_va_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr);
}
-
-
- if ((instr[index] == (uchar_t)0x0f) &&
- (instr[index + 1] == (uchar_t)0x01)) {
- addr_t first_operand;
- addr_t second_operand;
- operand_type_t addr_type;
- addr_t guest_cr3 = CR3_TO_PDE32(info->shdw_pg_state.guest_cr3);
-
- pde32_t * guest_pd = NULL;
-
- if (guest_pa_to_host_va(info, guest_cr3, (addr_t*)&guest_pd) == -1) {
- PrintError("Invalid Guest PDE Address: 0x%x\n", guest_cr3);
+ if (ret == -1) {
+ PrintError("Could not read instruction into buffer\n");
return -1;
- }
+ }
-
+ if (v3_decode(info, (addr_t)instr, &dec_instr) == -1) {
+ PrintError("Decoding Error\n");
+ return -1;
+ }
+
+ if ((dec_instr.op_type != V3_OP_INVLPG) ||
+ (dec_instr.num_operands != 1) ||
+ (dec_instr.dst_operand.type != MEM_OPERAND)) {
+ PrintError("Decoder Error: Not a valid INVLPG instruction...\n");
+ return -1;
+ }
+ vaddr = dec_instr.dst_operand.operand;
+
+ info->rip += dec_instr.instr_length;
+
+ switch (v3_get_vm_cpu_mode(info)) {
+ case PROTECTED:
+ return handle_shadow_invlpg_32(info, vaddr);
+ case PROTECTED_PAE:
+ return handle_shadow_invlpg_32pae(info, vaddr);
+ case LONG:
+ case LONG_32_COMPAT:
+ case LONG_16_COMPAT:
+ return handle_shadow_invlpg_64(info, vaddr);
+ default:
+ PrintError("Invalid CPU mode: %s\n", v3_cpu_mode_to_str(v3_get_vm_cpu_mode(info)));
+ return -1;
+ }
+}
- index += 2;
- addr_type = decode_operands32(&(info->vm_regs), instr + index, &index, &first_operand, &second_operand, REG32);
- if (addr_type == MEM_OPERAND) {
- pde32_t * shadow_pd = (pde32_t *)CR3_TO_PDE32(info->shdw_pg_state.shadow_cr3);
- pde32_t * shadow_pde = (pde32_t *)&shadow_pd[PDE32_INDEX(first_operand)];
- pde32_t * guest_pde;
- //PrintDebug("PDE Index=%d\n", PDE32_INDEX(first_operand));
- //PrintDebug("FirstOperand = %x\n", first_operand);
+static struct shadow_page_data * create_new_shadow_pt(struct guest_info * info) {
+ struct shadow_page_state * state = &(info->shdw_pg_state);
+ v3_reg_t cur_cr3 = info->ctrl_regs.cr3;
+ struct shadow_page_data * page_tail = NULL;
+ addr_t shdw_page = 0;
- PrintDebug("Invalidating page for %x\n", first_operand);
+ if (!list_empty(&(state->page_list))) {
+ page_tail = list_tail_entry(&(state->page_list), struct shadow_page_data, page_list_node);
+
+ if (page_tail->cr3 != cur_cr3) {
+ PrintDebug("Reusing old shadow Page: %p (cur_CR3=%p)(page_cr3=%p) \n",
+ (void *)(addr_t)page_tail->page_pa,
+ (void *)(addr_t)cur_cr3,
+ (void *)(addr_t)(page_tail->cr3));
- guest_pde = (pde32_t *)&(guest_pd[PDE32_INDEX(first_operand)]);
+ list_move(&(page_tail->page_list_node), &(state->page_list));
- if (guest_pde->large_page == 1) {
- shadow_pde->present = 0;
- PrintDebug("Invalidating Large Page\n");
- } else {
-
- if (shadow_pde->present == 1) {
- pte32_t * shadow_pt = (pte32_t *)PDE32_T_ADDR((*shadow_pde));
- pte32_t * shadow_pte = (pte32_t *)&shadow_pt[PTE32_INDEX(first_operand)];
+ memset(V3_VAddr((void *)(page_tail->page_pa)), 0, PAGE_SIZE_4KB);
-#ifdef DEBUG_SHADOW_PAGING
- PrintDebug("Setting not present\n");
- PrintPTE32(first_operand, shadow_pte);
-#endif
- shadow_pte->present = 0;
- }
+ return page_tail;
}
-
- info->rip += index;
-
- } else {
- PrintError("Invalid Operand type\n");
- return -1;
- }
- } else {
- PrintError("invalid Instruction Opcode\n");
- PrintTraceMemDump(instr, 15);
- return -1;
}
- }
- return 0;
-}
+ // else
+ page_tail = (struct shadow_page_data *)V3_Malloc(sizeof(struct shadow_page_data));
+ page_tail->page_pa = (addr_t)V3_AllocPages(1);
-/*
+ PrintDebug("Allocating new shadow Page: %p (cur_cr3=%p)\n",
+ (void *)(addr_t)page_tail->page_pa,
+ (void *)(addr_t)cur_cr3);
+ page_tail->cr3 = cur_cr3;
+ list_add(&(page_tail->page_list_node), &(state->page_list));
-static int create_pd32_nonaligned_4MB_page(struct guest_info * info, pte32_t * pt, addr_t guest_addr, pde32_4MB_t * large_shadow_pde) {
- uint_t i = 0;
- pte32_t * pte_cursor;
- addr_t guest_pa = 0;
+ shdw_page = (addr_t)V3_VAddr((void *)(page_tail->page_pa));
+ memset((void *)shdw_page, 0, PAGE_SIZE_4KB);
- for (i = 0; i < 1024; i++) {
- guest_pa = guest_addr + (PAGE_SIZE * i);
- host_region_type_t host_page_type = get_shadow_addr_type(info, guest_pa);
-
- pte_cursor = &(pt[i]);
+ return page_tail;
+}
- if (host_page_type == HOST_REGION_INVALID) {
- // Currently we don't support this, but in theory we could
- PrintError("Invalid Host Memory Type\n");
- return -1;
- } else if (host_page_type == HOST_REGION_PHYSICAL_MEMORY) {
- addr_t shadow_pa = get_shadow_addr(info, guest_pa);
+static int inject_guest_pf(struct guest_info * info, addr_t fault_addr, pf_error_t error_code) {
+ info->ctrl_regs.cr2 = fault_addr;
- pte_cursor->page_base_addr = PT32_BASE_ADDR(shadow_pa);
- pte_cursor->present = 1;
- pte_cursor->writable = large_shadow_pde->writable;
- pte_cursor->user_page = large_shadow_pde->user_page;
- pte_cursor->write_through = 0;
- pte_cursor->cache_disable = 0;
- pte_cursor->global_page = 0;
+#ifdef CONFIG_SHADOW_PAGING_TELEMETRY
+ info->shdw_pg_state.guest_faults++;
+#endif
- } else {
- PrintError("Unsupported Host Memory Type\n");
- return -1;
- }
- }
- return 0;
+ return v3_raise_exception_with_error(info, PF_EXCEPTION, *(uint_t *)&error_code);
}
-static int handle_large_pagefault32(struct guest_info * info,
- pde32_t * guest_pde, pde32_t * shadow_pde,
- addr_t fault_addr, pf_error_t error_code ) {
- struct shadow_region * mem_reg;
- pde32_4MB_t * large_guest_pde = (pde32_4MB_t *)guest_pde;
- pde32_4MB_t * large_shadow_pde = (pde32_4MB_t *)shadow_pde;
- host_region_type_t host_page_type;
- addr_t guest_start_addr = PDE32_4MB_T_ADDR(*large_guest_pde);
- // addr_t guest_end_addr = guest_start_addr + PAGE_SIZE_4MB; // start address + 4MB
-
-
- // Check that the Guest PDE entry points to valid memory
- // else Machine Check the guest
- PrintDebug("Large Page: Page Base Addr=%x\n", guest_start_addr);
-
- host_page_type = get_shadow_addr_type(info, guest_start_addr);
-
- if (host_page_type == HOST_REGION_INVALID) {
- PrintError("Invalid guest address in large page (0x%x)\n", guest_start_addr);
- v3_raise_exception(info, MC_EXCEPTION);
- return -1;
- }
-
- // else...
+static int is_guest_pf(pt_access_status_t guest_access, pt_access_status_t shadow_access) {
+ /* basically the reasoning is that there can be multiple reasons for a page fault:
+ If there is a permissions failure for a page present in the guest _BUT_
+ the reason for the fault was that the page is not present in the shadow,
+ _THEN_ we have to map the shadow page in and reexecute, this will generate
+ a permissions fault which is _THEN_ valid to send to the guest
+ _UNLESS_ both the guest and shadow have marked the page as not present
+
+ whew...
+ */
+ if (guest_access != PT_ACCESS_OK) {
+ // Guest Access Error
+
+ if ((shadow_access != PT_ACCESS_NOT_PRESENT) &&
+ (guest_access != PT_ACCESS_NOT_PRESENT)) {
+ // aka (guest permission error)
+ return 1;
+ }
- if (host_page_type == HOST_REGION_PHYSICAL_MEMORY) {
+ /*
+ if ((shadow_access == PT_ACCESS_NOT_PRESENT) &&
+ (guest_access == PT_ACCESS_NOT_PRESENT)) {
+ // Page tables completely blank, handle guest first
+ return 1;
+ }
+ */
- addr_t host_start_addr = 0;
- addr_t region_end_addr = 0;
-
- // Check for a large enough region in host memory
- mem_reg = get_shadow_region_by_addr(&(info->mem_map), guest_start_addr);
- PrintDebug("Host region: host_addr=%x (guest_start=%x, end=%x)\n",
- mem_reg->host_addr, mem_reg->guest_start, mem_reg->guest_end);
- host_start_addr = mem_reg->host_addr + (guest_start_addr - mem_reg->guest_start);
- region_end_addr = mem_reg->host_addr + (mem_reg->guest_end - mem_reg->guest_start);
-
- PrintDebug("Host Start Addr=%x; Region End Addr=%x\n", host_start_addr, region_end_addr);
-
-
- //4f
- if (large_guest_pde->dirty == 1) { // dirty
- large_shadow_pde->writable = guest_pde->writable;
- } else if (error_code.write == 1) { // not dirty, access is write
- large_shadow_pde->writable = guest_pde->writable;
- large_guest_pde->dirty = 1;
- } else { // not dirty, access is read
- large_shadow_pde->writable = 0;
- }
-
-
- // Check if the region is at least an additional 4MB
-
-
- //4b.
- if ((PD32_4MB_PAGE_OFFSET(host_start_addr) == 0) &&
- (region_end_addr >= host_start_addr + PAGE_SIZE_4MB)) { // if 4MB boundary
- large_shadow_pde->page_base_addr = PD32_4MB_BASE_ADDR(host_start_addr);
- } else { // else generate 4k pages
- pte32_t * shadow_pt = NULL;
- PrintDebug("Handling non aligned large page\n");
-
- shadow_pde->large_page = 0;
-
- shadow_pt = create_new_shadow_pt32();
-
- if (create_pd32_nonaligned_4MB_page(info, shadow_pt, guest_start_addr, large_shadow_pde) == -1) {
- PrintError("Non Aligned Large Page Error\n");
- V3_Free(shadow_pt);
- return -1;
- }
-
-
-#ifdef DEBUG_SHADOW_PAGING
- PrintDebug("non-aligned Shadow PT\n");
- PrintPT32(PT32_PAGE_ADDR(fault_addr), shadow_pt);
-#endif
- shadow_pde->pt_base_addr = PD32_BASE_ADDR(shadow_pt);
- }
-
- } else {
- // Handle hooked pages as well as other special pages
- if (handle_special_page_fault(info, fault_addr, guest_start_addr, error_code) == -1) {
- PrintError("Special Page Fault handler returned error for address: %x\n", fault_addr);
- return -1;
+ if (guest_access == PT_ACCESS_NOT_PRESENT) {
+ // Page tables completely blank, handle guest first
+ return 1;
+ }
+
+ // Otherwise we'll handle the guest fault later...?
}
- }
- return 0;
+ return 0;
}
-*/
+
+
