X-Git-Url: http://v3vee.org/palacios/gitweb/gitweb.cgi?p=palacios.git;a=blobdiff_plain;f=palacios%2Fsrc%2Fpalacios%2Fvmm_shadow_paging.c;h=eeb493bc841b5e6380d0bdec559ae14b9667be85;hp=6a0b3be9053632b01c9db701531a00d3428068ee;hb=316c417125ed34aaa60f9fc5486a6d8dec4fb361;hpb=53f181096ad02cde9f79e30e2238ddad43ede574 diff --git a/palacios/src/palacios/vmm_shadow_paging.c b/palacios/src/palacios/vmm_shadow_paging.c index 6a0b3be..eeb493b 100644 --- a/palacios/src/palacios/vmm_shadow_paging.c +++ b/palacios/src/palacios/vmm_shadow_paging.c @@ -28,7 +28,13 @@ #include -#ifndef DEBUG_SHADOW_PAGING +#include + +#ifdef CONFIG_SYMBIOTIC_SWAP +#include +#endif + +#ifndef CONFIG_DEBUG_SHADOW_PAGING #undef PrintDebug #define PrintDebug(fmt, args...) #endif @@ -39,50 +45,17 @@ ***/ -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; + v3_reg_t cr3; + addr_t page_pa; + + struct list_head page_list_node; }; - -//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 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); @@ -93,242 +66,230 @@ static int is_guest_pf(pt_access_status_t guest_access, pt_access_status_t shado int v3_init_shadow_page_state(struct guest_info * info) { - struct shadow_page_state * state = &(info->shdw_pg_state); + struct shadow_page_state * state = &(info->shdw_pg_state); - state->guest_cr3 = 0; - state->guest_cr0 = 0; - - state->cached_ptes = NULL; + state->guest_cr3 = 0; + state->guest_cr0 = 0; + state->guest_efer.value = 0x0LL; - return 0; + INIT_LIST_HEAD(&(state->page_list)); + + 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 (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; + 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; + } + + 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; +// 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); } - int v3_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 - -#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; + 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 { + PrintError("Invalid Memory mode\n"); + return -1; } - } else { - PrintError("Invalid Memory mode\n"); - return -1; - } } +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; -static addr_t create_new_shadow_pt() { - void * host_pde = 0; + 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; + } + + 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 (ret == -1) { + PrintError("Could not read instruction into buffer\n"); + return -1; + } - host_pde = V3_VAddr(V3_AllocPages(1)); - memset(host_pde, 0, PAGE_SIZE); + 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; + } - return (addr_t)host_pde; + 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; + } } -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++; - } - info->ctrl_regs.cr2 = fault_addr; - v3_raise_exception_with_error(info, PF_EXCEPTION, *(uint_t *)&error_code); -} +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; -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 (!list_empty(&(state->page_list))) { + page_tail = list_tail_entry(&(state->page_list), struct shadow_page_data, page_list_node); - if ((shadow_access != PT_ACCESS_NOT_PRESENT) && - (guest_access != PT_ACCESS_NOT_PRESENT)) { - // aka (guest permission error) - return 1; - } + 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)); - if ((shadow_access == PT_ACCESS_NOT_PRESENT) && - (guest_access == PT_ACCESS_NOT_PRESENT)) { - // Page tables completely blank, handle guest first - return 1; - } + list_move(&(page_tail->page_list_node), &(state->page_list)); - // Otherwise we'll handle the guest fault later...? - } + memset(V3_VAddr((void *)(page_tail->page_pa)), 0, PAGE_SIZE_4KB); - return 0; -} + return page_tail; + } + } + // 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)); + shdw_page = (addr_t)V3_VAddr((void *)(page_tail->page_pa)); + memset((void *)shdw_page, 0, PAGE_SIZE_4KB); + return page_tail; +} +static int inject_guest_pf(struct guest_info * info, addr_t fault_addr, pf_error_t error_code) { +#ifdef CONFIG_PROFILE_VMM + if (info->enable_profiler) { + info->profiler.guest_pf_cnt++; + } +#endif + info->ctrl_regs.cr2 = fault_addr; -/* 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 v3_raise_exception_with_error(info, PF_EXCEPTION, *(uint_t *)&error_code); +} - 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; + +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 ((shadow_access == PT_ACCESS_NOT_PRESENT) && + (guest_access == PT_ACCESS_NOT_PRESENT)) { + // Page tables completely blank, handle guest first + 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...? } - - info->rip += index; - - return 0; + + return 0; }