+/*
+ * 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>
+
+#include <palacios/vmm_direct_paging.h>
+
+#ifndef DEBUG_SHADOW_PAGING
+#undef PrintDebug
+#define PrintDebug(fmt, args...)
+#endif
-extern struct vmm_os_hooks * os_hooks;
+/***
+ *** There be dragons
+ ***/
-int init_shadow_page_state(struct shadow_page_state * state) {
- state->guest_mode = PDE32;
- state->shadow_mode = PDE32;
+
+struct shadow_page_data {
+ v3_reg_t cr3;
+ addr_t page_pa;
+
+ struct list_head page_list_node;
+};
+
+
+DEFINE_HASHTABLE_INSERT(add_pte_map, addr_t, addr_t);
+DEFINE_HASHTABLE_SEARCH(find_pte_map, addr_t, addr_t);
+//DEFINE_HASHTABLE_REMOVE(del_pte_map, addr_t, addr_t, 0);
+
+
+
+static uint_t pte_hash_fn(addr_t key) {
+ return hash_long(key, 32);
+}
+
+static int pte_equals(addr_t key1, addr_t key2) {
+ return (key1 == key2);
+}
+
+static struct shadow_page_data * create_new_shadow_pt(struct guest_info * info);
+static void 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);
+
+
+#include "vmm_shadow_paging_32.h"
+#include "vmm_shadow_paging_32pae.h"
+#include "vmm_shadow_paging_64.h"
+
+
+
+int v3_init_shadow_page_state(struct guest_info * info) {
+ struct shadow_page_state * state = &(info->shdw_pg_state);
state->guest_cr3 = 0;
- state->shadow_cr3 = 0;
+ state->guest_cr0 = 0;
+
+ INIT_LIST_HEAD(&(state->page_list));
+
+ state->cached_ptes = NULL;
+ state->cached_cr3 = 0;
+
+ return 0;
+}
+
+
+
+// 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_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_cpu_mode(info)));
+ return -1;
+ }
+
+ return 0;
+}
+
+int v3_activate_passthrough_pt(struct guest_info * info) {
+ // For now... But we need to change this....
+ // As soon as shadow paging becomes active the passthrough tables are hosed
+ // So this will cause chaos if it is called at that time
+
+ info->ctrl_regs.cr3 = *(addr_t*)&(info->direct_map_pt);
+ //PrintError("Activate Passthrough Page tables not implemented\n");
return 0;
}
-int handle_shadow_pagefault(struct guest_info * info, addr_t fault_addr, pf_error_t error_code) {
- if (info->cpu_mode == PROTECTED_PG) {
- return handle_shadow_pagefault32(info, fault_addr, error_code);
+
+
+int v3_handle_shadow_pagefault(struct guest_info * info, addr_t fault_addr, pf_error_t error_code) {
+
+ if (v3_get_mem_mode(info) == PHYSICAL_MEM) {
+ // If paging is not turned on we need to handle the special cases
+ return v3_handle_shadow_pagefault_physical_mode(info, fault_addr, error_code);
+ } else if (v3_get_mem_mode(info) == VIRTUAL_MEM) {
+
+ switch (v3_get_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_cpu_mode(info)));
+ return -1;
+ }
} else {
+ PrintError("Invalid Memory mode\n");
return -1;
}
}
-int handle_shadow_pagefault32(struct guest_info * info, addr_t fault_addr, pf_error_t error_code) {
- pde32_t * guest_pde = NULL;
- pde32_t * shadow_pde = (pde32_t *)CR3_TO_PDE32(info->shdw_pg_state.shadow_cr3);
- addr_t guest_cr3 = CR3_TO_PDE32(info->shdw_pg_state.guest_cr3);
+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;
- if (guest_pa_to_host_va(info, guest_cr3, (addr_t*)&guest_pde) == -1) {
+ if (v3_get_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;
}
- if (error_code.present == 0) {
- // Faulted because page was not present...
- if (shadow_pde[PDE32_INDEX(fault_addr)].present) {
-
-
- } else {
- return -1;
- }
+ if (v3_get_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 (ret == -1) {
+ PrintError("Could not read instruction into buffer\n");
+ return -1;
}
- // Checks:
- // Shadow PDE
- // Guest PDE
- // Shadow PTE
- // Guest PTE
- // Mem Map
+ if (v3_decode(info, (addr_t)instr, &dec_instr) == -1) {
+ PrintError("Decoding Error\n");
+ return -1;
+ }
- 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_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_cpu_mode(info)));
+ return -1;
+ }
}
-addr_t create_new_shadow_pt32(struct guest_info * info) {
- void * host_pde = 0;
- V3_AllocPages(host_pde, 1);
- memset(host_pde, 0, PAGE_SIZE);
- return (addr_t)host_pde;
-}
+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;
+ 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 *) page_tail->page_pa, (void *)cur_cr3, (void *)(page_tail->cr3));
+ list_move(&(page_tail->page_list_node), &(state->page_list));
+ memset(V3_VAddr((void *)(page_tail->page_pa)), 0, PAGE_SIZE_4KB);
-addr_t setup_shadow_pt32(struct guest_info * info, addr_t virt_cr3) {
- addr_t cr3_guest_addr = CR3_TO_PDE32(virt_cr3);
- pde32_t * guest_pde;
- pde32_t * host_pde = NULL;
- int i;
-
- // Setup up guest_pde to point to the PageDir in host addr
- if (guest_pa_to_host_va(info, cr3_guest_addr, (addr_t*)&guest_pde) == -1) {
- return 0;
- }
-
- V3_AllocPages(host_pde, 1);
- memset(host_pde, 0, PAGE_SIZE);
- for (i = 0; i < MAX_PDE32_ENTRIES; i++) {
- if (guest_pde[i].present == 1) {
- addr_t pt_host_addr;
- addr_t host_pte;
+ return page_tail;
+ }
+ }
- if (guest_pa_to_host_va(info, PDE32_T_ADDR(guest_pde[i]), &pt_host_addr) == -1) {
- return 0;
- }
+ // else
- if ((host_pte = setup_shadow_pte32(info, pt_host_addr)) == 0) {
- return 0;
- }
+ page_tail = (struct shadow_page_data *)V3_Malloc(sizeof(struct shadow_page_data));
+ page_tail->page_pa = (addr_t)V3_AllocPages(1);
- host_pde[i].present = 1;
- host_pde[i].pt_base_addr = PD32_BASE_ADDR(host_pte);
+ PrintDebug("Allocating new shadow Page: %p (cur_cr3=%p)\n", (void *)page_tail->page_pa, (void *)cur_cr3);
- //
- // Set Page DIR flags
- //
- }
- }
+ page_tail->cr3 = cur_cr3;
+ list_add(&(page_tail->page_list_node), &(state->page_list));
- PrintDebugPageTables(host_pde);
+ shdw_page = (addr_t)V3_VAddr((void *)(page_tail->page_pa));
+ memset((void *)shdw_page, 0, PAGE_SIZE_4KB);
- return (addr_t)host_pde;
+ return page_tail;
}
+static void inject_guest_pf(struct guest_info * info, addr_t fault_addr, pf_error_t error_code) {
+ if (info->enable_profiler) {
+ info->profiler.guest_pf_cnt++;
+ }
-addr_t setup_shadow_pte32(struct guest_info * info, addr_t pt_host_addr) {
- pte32_t * guest_pte = (pte32_t *)pt_host_addr;
- pte32_t * host_pte = NULL;
- int i;
+ info->ctrl_regs.cr2 = fault_addr;
+ v3_raise_exception_with_error(info, PF_EXCEPTION, *(uint_t *)&error_code);
+}
- V3_AllocPages(host_pte, 1);
- memset(host_pte, 0, PAGE_SIZE);
- for (i = 0; i < MAX_PTE32_ENTRIES; i++) {
- if (guest_pte[i].present == 1) {
- addr_t guest_pa = PTE32_T_ADDR(guest_pte[i]);
- shadow_mem_type_t page_type;
- addr_t host_pa = 0;
+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
- page_type = get_shadow_addr_type(info, guest_pa);
+ whew...
+ */
+ if (guest_access != PT_ACCESS_OK) {
+ // Guest Access Error
- if (page_type == HOST_REGION_PHYSICAL_MEMORY) {
- host_pa = get_shadow_addr(info, guest_pa);
- } else {
-
- //
- // Setup various memory types
- //
- }
+ if ((shadow_access != PT_ACCESS_NOT_PRESENT) &&
+ (guest_access != PT_ACCESS_NOT_PRESENT)) {
+ // aka (guest permission error)
+ return 1;
+ }
- host_pte[i].page_base_addr = PT32_BASE_ADDR(host_pa);
- host_pte[i].present = 1;
+ if ((shadow_access == PT_ACCESS_NOT_PRESENT) &&
+ (guest_access == PT_ACCESS_NOT_PRESENT)) {
+ // Page tables completely blank, handle guest first
+ return 1;
}
+
+ // Otherwise we'll handle the guest fault later...?
}
- return (addr_t)host_pte;
+ return 0;
}
