X-Git-Url: http://v3vee.org/palacios/gitweb/gitweb.cgi?a=blobdiff_plain;f=palacios%2Fsrc%2Fpalacios%2Fvmm_shadow_paging.c;h=6a0b3be9053632b01c9db701531a00d3428068ee;hb=53f181096ad02cde9f79e30e2238ddad43ede574;hp=57fade1b85509dae5e90c2bebf3988642f547423;hpb=2b1f4ef19d766727f873476861c64339c8836a40;p=palacios.git diff --git a/palacios/src/palacios/vmm_shadow_paging.c b/palacios/src/palacios/vmm_shadow_paging.c index 57fade1..6a0b3be 100644 --- a/palacios/src/palacios/vmm_shadow_paging.c +++ b/palacios/src/palacios/vmm_shadow_paging.c @@ -1,147 +1,334 @@ +/* + * 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 + * Copyright (c) 2008, The V3VEE Project + * All rights reserved. + * + * Author: Jack Lange + * + * This is free software. You are permitted to use, + * redistribute, and modify it as specified in the file "V3VEE_LICENSE". + */ + + #include #include #include +#include +#include + +#include + +#ifndef DEBUG_SHADOW_PAGING +#undef PrintDebug +#define PrintDebug(fmt, args...) +#endif + + +/*** + *** There be dragons + ***/ + + +struct guest_table { + addr_t cr3; + struct list_head link; +}; + + +struct backptr { + addr_t ptr; + struct list_head link; +}; + + +struct shadow_page_data { + addr_t ptr; + addr_t guest_addr; + + struct list_head backptrs; + struct list_head guest_tables; +}; + + + + +//DEFINE_HASHTABLE_INSERT(add_cr3_to_cache, addr_t, struct hashtable *); +//DEFINE_HASHTABLE_SEARCH(find_cr3_in_cache, addr_t, struct hashtable *); +//DEFINE_HASHTABLE_REMOVE(del_cr3_from_cache, addr_t, struct hashtable *, 0); + + +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 addr_t create_new_shadow_pt(); +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); + -extern struct vmm_os_hooks * os_hooks; +#include "vmm_shadow_paging_32.h" +#include "vmm_shadow_paging_32pae.h" +#include "vmm_shadow_paging_64.h" -int init_shadow_page_state(struct shadow_page_state * state) { - state->guest_mode = PDE32; - state->shadow_mode = PDE32; + +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; + + state->cached_ptes = NULL; 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); - } else { + + + + + + +// 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 (info->cpu_mode) { + + 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: %d\n", info->cpu_mode); return -1; } + + return 0; } -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_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; +} - if (guest_pa_to_host_va(info, guest_cr3, (addr_t*)&guest_pde) == -1) { - return -1; - } - if (error_code.present == 0) { - // Faulted because page was not present... - if (shadow_pde[PDE32_INDEX(fault_addr)].present) { - - - } else { - return -1; - } - } - // Checks: - // Shadow PDE - // Guest PDE - // Shadow PTE - // Guest PTE - // Mem Map +int v3_handle_shadow_pagefault(struct guest_info * info, addr_t fault_addr, pf_error_t error_code) { - return -1; + if (info->mem_mode == PHYSICAL_MEM) { + // If paging is not turned on we need to handle the special cases + +#ifdef DEBUG_SHADOW_PAGING + PrintHostPageTree(info->cpu_mode, fault_addr, info->ctrl_regs.cr3); + PrintGuestPageTree(info, fault_addr, info->shdw_pg_state.guest_cr3); +#endif + + 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_pagefault_32(info, fault_addr, error_code); + break; + case PROTECTED_PAE: + return handle_shadow_pagefault_32pae(info, fault_addr, error_code); + case LONG: + return handle_shadow_pagefault_64(info, fault_addr, error_code); + break; + default: + PrintError("Unhandled CPU Mode\n"); + return -1; + } + } else { + PrintError("Invalid Memory mode\n"); + return -1; + } } -addr_t create_new_shadow_pt32(struct guest_info * info) { + +static addr_t create_new_shadow_pt() { void * host_pde = 0; - V3_AllocPages(host_pde, 1); + host_pde = V3_VAddr(V3_AllocPages(1)); memset(host_pde, 0, PAGE_SIZE); return (addr_t)host_pde; } - - -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; +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++; } - - 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; - if (guest_pa_to_host_va(info, PDE32_T_ADDR(guest_pde[i]), &pt_host_addr) == -1) { - return 0; - } + info->ctrl_regs.cr2 = fault_addr; + v3_raise_exception_with_error(info, PF_EXCEPTION, *(uint_t *)&error_code); +} - if ((host_pte = setup_shadow_pte32(info, pt_host_addr)) == 0) { - return 0; - } - host_pde[i].present = 1; - host_pde[i].pt_base_addr = PD32_BASE_ADDR(host_pte); +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; + } - // - // Set Page DIR flags - // + if ((shadow_access == PT_ACCESS_NOT_PRESENT) && + (guest_access == PT_ACCESS_NOT_PRESENT)) { + // Page tables completely blank, handle guest first + return 1; } - } - PrintDebugPageTables(host_pde); + // Otherwise we'll handle the guest fault later...? + } - return (addr_t)host_pde; + return 0; } -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; - 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; - page_type = get_shadow_addr_type(info, guest_pa); - if (page_type == HOST_REGION_PHYSICAL_MEMORY) { - host_pa = get_shadow_addr(info, guest_pa); - } else { - - // - // Setup various memory types - // - } - host_pte[i].page_base_addr = PT32_BASE_ADDR(host_pa); - host_pte[i].present = 1; - } + + + + +/* Currently Does not work with Segmentation!!! */ +int v3_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) { + PrintError("Unsupported CPU mode (mode=%s)\n", v3_cpu_mode_to_str(info->cpu_mode)); + return -1; + } + + uchar_t instr[15]; + int index = 0; + + int 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%p (ret=%d)\n", (void *)(addr_t)(info->rip), ret); + return -1; } + + + /* Can INVLPG work with Segments?? */ + while (is_prefix_byte(instr[index])) { + index++; + } + + + if( (instr[index + 0] != (uchar_t) 0x0f) || + (instr[index + 1] != (uchar_t) 0x01) ) { + PrintError("invalid Instruction Opcode\n"); + PrintTraceMemDump(instr, 15); + return -1; + } + + addr_t first_operand; + addr_t second_operand; + addr_t guest_cr3 = CR3_TO_PDE32_PA(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%p\n", (void *)guest_cr3); + return -1; + } + + index += 2; - return (addr_t)host_pte; + v3_operand_type_t addr_type = decode_operands32(&(info->vm_regs), instr + index, &index, &first_operand, &second_operand, REG32); + + if (addr_type != MEM_OPERAND) { + PrintError("Invalid Operand type\n"); + return -1; + } + + pde32_t * shadow_pd = (pde32_t *)CR3_TO_PDE32_VA(info->ctrl_regs.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); + + PrintDebug("Invalidating page for %p\n", (void *)first_operand); + + guest_pde = (pde32_t *)&(guest_pd[PDE32_INDEX(first_operand)]); + + 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 *)(addr_t)BASE_TO_PAGE_ADDR(shadow_pde->pt_base_addr); + pte32_t * shadow_pte = (pte32_t *) V3_VAddr( (void*) &shadow_pt[PTE32_INDEX(first_operand)] ); + +#ifdef DEBUG_SHADOW_PAGING + PrintDebug("Setting not present\n"); + PrintPTEntry(PAGE_PT32, first_operand, shadow_pte); +#endif + + shadow_pte->present = 0; + } + + info->rip += index; + + return 0; }