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=0afc383269000e456d57847a5cdfc6c5d86a1973;hp=4e6b573bae38193b98fb59a277c6c612e72a089c;hb=0e097100a26bc43eb8964734fa43130fc4c71429;hpb=ff90d0325fbbecf4d2acef912e830a711526c913 diff --git a/palacios/src/palacios/vmm_shadow_paging.c b/palacios/src/palacios/vmm_shadow_paging.c index 4e6b573..0afc383 100644 --- a/palacios/src/palacios/vmm_shadow_paging.c +++ b/palacios/src/palacios/vmm_shadow_paging.c @@ -26,7 +26,20 @@ #include #include -#ifndef DEBUG_SHADOW_PAGING +#include + +#include + + +#ifdef CONFIG_SHADOW_PAGING_TELEMETRY +#include +#endif + +#ifdef CONFIG_SYMBIOTIC_SWAP +#include +#endif + +#ifndef CONFIG_DEBUG_SHADOW_PAGING #undef PrintDebug #define PrintDebug(fmt, args...) #endif @@ -37,1046 +50,262 @@ ***/ +struct shadow_page_data { + 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 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); -static uint_t pte_hash_fn(addr_t key) { - return hash_long(key, 32); -} +#include "vmm_shadow_paging_32.h" +#include "vmm_shadow_paging_32pae.h" +#include "vmm_shadow_paging_64.h" -static int pte_equals(addr_t key1, addr_t key2) { - return (key1 == key2); -} -static uint_t cr3_hash_fn(addr_t key) { - return hash_long(key, 32); -} -static int cr3_equals(addr_t key1, addr_t key2) { - return (key1 == key2); +#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 -static int activate_shadow_pt_32(struct guest_info * info); -static int activate_shadow_pt_32pae(struct guest_info * info); -static int activate_shadow_pt_64(struct guest_info * info); - - -static int handle_shadow_pagefault_32(struct guest_info * info, addr_t fault_addr, pf_error_t error_code); -static int handle_shadow_pagefault_32pae(struct guest_info * info, addr_t fault_addr, pf_error_t error_code); -static int handle_shadow_pagefault_64(struct guest_info * info, addr_t fault_addr, pf_error_t error_code); - - -static int cache_page_tables_32(struct guest_info * info, addr_t pde); - 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->cr3_cache = create_hashtable(0, &cr3_hash_fn, &cr3_equals); - - state->cached_cr3 = 0; - state->cached_ptes = NULL; - - return 0; -} - - - - -/* - For now we'll do something a little more lightweight -int cache_page_tables32(struct guest_info * info, addr_t pde) { - struct shadow_page_state * state = &(info->shdw_pg_state); - addr_t pde_host_addr; - pde32_t * tmp_pde; - struct hashtable * pte_cache = NULL; - int i = 0; - - - pte_cache = (struct hashtable *)find_cr3_in_cache(state->cr3_cache, pde); - if (pte_cache != NULL) { - PrintError("CR3 already present in cache\n"); - state->current_ptes = pte_cache; - return 1; - } else { - PrintError("Creating new CR3 cache entry\n"); - pte_cache = create_hashtable(0, &pte_hash_fn, &pte_equals); - state->current_ptes = pte_cache; - add_cr3_to_cache(state->cr3_cache, pde, pte_cache); - } - - if (guest_pa_to_host_va(info, pde, &pde_host_addr) == -1) { - PrintError("Could not lookup host address of guest PDE\n"); - return -1; - } - - tmp_pde = (pde32_t *)pde_host_addr; - - add_pte_map(pte_cache, pde, pde_host_addr); + state->guest_cr3 = 0; + state->guest_cr0 = 0; + state->guest_efer.value = 0x0LL; + INIT_LIST_HEAD(&(state->page_list)); - for (i = 0; i < MAX_PDE32_ENTRIES; i++) { - if ((tmp_pde[i].present) && (tmp_pde[i].large_page == 0)) { - addr_t pte_host_addr; - - if (guest_pa_to_host_va(info, (addr_t)(PDE32_T_ADDR(tmp_pde[i])), &pte_host_addr) == -1) { - PrintError("Could not lookup host address of guest PDE\n"); - return -1; - } - - add_pte_map(pte_cache, (addr_t)(PDE32_T_ADDR(tmp_pde[i])), pte_host_addr); - } - } - - - return 0; -} -*/ - - -int v3_cache_page_tables(struct guest_info * info, addr_t cr3) { - switch(v3_get_cpu_mode(info)) { - case PROTECTED: - return cache_page_tables_32(info, CR3_TO_PDE32_PA(cr3)); - default: - return -1; - } -} - -static int cache_page_tables_32(struct guest_info * info, addr_t pde) { - struct shadow_page_state * state = &(info->shdw_pg_state); - addr_t pde_host_addr; - pde32_t * tmp_pde; - struct hashtable * pte_cache = NULL; - int i = 0; - - if (pde == state->cached_cr3) { - return 1; - } - - if (state->cached_ptes != NULL) { - hashtable_destroy(state->cached_ptes, 0, 0); - state->cached_ptes = NULL; - } - - state->cached_cr3 = pde; - - pte_cache = create_hashtable(0, &pte_hash_fn, &pte_equals); - state->cached_ptes = pte_cache; - - if (guest_pa_to_host_va(info, pde, &pde_host_addr) == -1) { - PrintError("Could not lookup host address of guest PDE\n"); - return -1; - } - - tmp_pde = (pde32_t *)pde_host_addr; - - add_pte_map(pte_cache, pde, pde_host_addr); - - - for (i = 0; i < MAX_PDE32_ENTRIES; i++) { - if ((tmp_pde[i].present) && (tmp_pde[i].large_page == 0)) { - addr_t pte_host_addr; - - if (guest_pa_to_host_va(info, (addr_t)(BASE_TO_PAGE_ADDR(tmp_pde[i].pt_base_addr)), &pte_host_addr) == -1) { - PrintError("Could not lookup host address of guest PDE\n"); - return -1; - } - - add_pte_map(pte_cache, (addr_t)(BASE_TO_PAGE_ADDR(tmp_pde[i].pt_base_addr)), pte_host_addr); +#ifdef CONFIG_SHADOW_PAGING_TELEMETRY + if (info->enable_telemetry) { + v3_add_telemetry_cb(info, telemetry_cb, NULL); } - } - - return 0; - -} - - - -int v3_replace_shdw_page32(struct guest_info * info, addr_t location, pte32_t * new_page, pte32_t * old_page) { - pde32_t * shadow_pd = (pde32_t *)CR3_TO_PDE32_VA(info->ctrl_regs.cr3); - pde32_t * shadow_pde = (pde32_t *)&(shadow_pd[PDE32_INDEX(location)]); - - if (shadow_pde->large_page == 0) { - pte32_t * shadow_pt = (pte32_t *)(addr_t)BASE_TO_PAGE_ADDR(shadow_pde->pt_base_addr); - pte32_t * shadow_pte = (pte32_t *)&(shadow_pt[PTE32_INDEX(location)]); - - //if (shadow_pte->present == 1) { - *(uint_t *)old_page = *(uint_t *)shadow_pte; - //} - - *(uint_t *)shadow_pte = *(uint_t *)new_page; - - } else { - // currently unhandled - PrintError("Replacing large shadow pages not implemented\n"); - return -1; - } - - return 0; -} - - - - - -// We assume that shdw_pg_state.guest_cr3 is pointing to the page tables we want to activate -// We also assume that the CPU mode has not changed during this page table transition -static int activate_shadow_pt_32(struct guest_info * info) { - struct cr3_32 * shadow_cr3 = (struct cr3_32 *)&(info->ctrl_regs.cr3); - struct cr3_32 * guest_cr3 = (struct cr3_32 *)&(info->shdw_pg_state.guest_cr3); - int cached = 0; - - // Check if shadow page tables are in the cache - cached = cache_page_tables_32(info, CR3_TO_PDE32_PA(*(addr_t *)guest_cr3)); - - if (cached == -1) { - PrintError("CR3 Cache failed\n"); - return -1; - } else if (cached == 0) { - addr_t shadow_pt; - - PrintDebug("New CR3 is different - flushing shadow page table %p\n", shadow_cr3 ); - delete_page_tables_32(CR3_TO_PDE32_VA(*(uint_t*)shadow_cr3)); - - shadow_pt = v3_create_new_shadow_pt(); - - shadow_cr3->pdt_base_addr = (addr_t)V3_PAddr((void *)(addr_t)PAGE_BASE_ADDR(shadow_pt)); - PrintDebug( "Created new shadow page table %p\n", (void *)(addr_t)shadow_cr3->pdt_base_addr ); - } else { - PrintDebug("Reusing cached shadow Page table\n"); - } - - shadow_cr3->pwt = guest_cr3->pwt; - shadow_cr3->pcd = guest_cr3->pcd; +#endif - return 0; -} - -static int activate_shadow_pt_32pae(struct guest_info * info) { - PrintError("Activating 32 bit PAE page tables not implemented\n"); - return -1; + return 0; } -static int activate_shadow_pt_64(struct guest_info * info) { - struct cr3_64 * shadow_cr3 = (struct cr3_64 *)&(info->ctrl_regs.cr3); - struct cr3_64 * guest_cr3 = (struct cr3_64 *)&(info->shdw_pg_state.guest_cr3); - int cached = 0; - - return -1; - // Check if shadow page tables are in the cache - cached = cache_page_tables_64(info, CR3_TO_PDE32_PA(*(addr_t *)guest_cr3)); - - if (cached == -1) { - PrintError("CR3 Cache failed\n"); - return -1; - } else if (cached == 0) { - addr_t shadow_pt; - - PrintDebug("New CR3 is different - flushing shadow page table %p\n", shadow_cr3 ); - delete_page_tables_32(CR3_TO_PDE32_VA(*(uint_t*)shadow_cr3)); - - shadow_pt = v3_create_new_shadow_pt(); - - shadow_cr3->pdt_base_addr = (addr_t)V3_PAddr((void *)(addr_t)PAGE_BASE_ADDR(shadow_pt)); - PrintDebug( "Created new shadow page table %p\n", (void *)(addr_t)shadow_cr3->pdt_base_addr ); - } else { - PrintDebug("Reusing cached shadow Page table\n"); - } - - shadow_cr3->pwt = guest_cr3->pwt; - shadow_cr3->pcd = guest_cr3->pcd; - - 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 - PrintPageTree(info->cpu_mode, fault_addr, info->ctrl_regs.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; - } } -addr_t v3_create_new_shadow_pt() { - void * host_pde = 0; - host_pde = V3_VAddr(V3_AllocPages(1)); - memset(host_pde, 0, PAGE_SIZE); +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; - 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_ACCESS_NOT_PRESENT) && - (guest_access != PT_ACCESS_NOT_PRESENT)) { - // aka (guest permission error) - 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; } - if ((shadow_access == PT_ACCESS_NOT_PRESENT) && - (guest_access == PT_ACCESS_NOT_PRESENT)) { - // Page tables completely blank, handle guest first - 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); } - // Otherwise we'll handle the guest fault later...? - } - - return 0; -} - - - - -/* - * * - * * - * * 64 bit Page table fault handlers - * * - * * - */ - -static int handle_shadow_pagefault_64(struct guest_info * info, addr_t fault_addr, pf_error_t error_code) { - pt_access_status_t guest_access; - pt_access_status_t shadow_access; - int ret; - PrintDebug("64 bit shadow page fault\n"); - - ret = v3_check_guest_pt_32(info, info->shdw_pg_state.guest_cr3, fault_addr, error_code, &guest_access); - - PrintDebug("Guest Access Check: %d (access=%d)\n", ret, guest_access); - - ret = v3_check_host_pt_32(info->ctrl_regs.cr3, fault_addr, error_code, &shadow_access); - - PrintDebug("Shadow Access Check: %d (access=%d)\n", ret, shadow_access); - - - PrintError("64 bit shadow paging not implemented\n"); - return -1; -} - - -/* - * * - * * - * * 32 bit PAE Page table fault handlers - * * - * * - */ - -static int handle_shadow_pagefault_32pae(struct guest_info * info, addr_t fault_addr, pf_error_t error_code) { - PrintError("32 bit PAE shadow paging not implemented\n"); - return -1; -} - - - - - - - -/* - * * - * * - * * 32 bit Page table fault handlers - * * - * * - */ -static int handle_large_pagefault_32(struct guest_info * info, - addr_t fault_addr, pf_error_t error_code, - pte32_t * shadow_pt, pde32_4MB_t * large_guest_pde); - -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); - - -static int handle_shadow_pagefault_32(struct guest_info * info, addr_t fault_addr, pf_error_t error_code) { - pde32_t * guest_pd = NULL; - pde32_t * shadow_pd = CR3_TO_PDE32_VA(info->ctrl_regs.cr3); - addr_t guest_cr3 = CR3_TO_PDE32_PA(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: %p\n", (void*) fault_addr ); - - 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; - } - - guest_pde = (pde32_t *)&(guest_pd[PDE32_INDEX(fault_addr)]); - - - // Check the guest page permissions - guest_pde_access = v3_can_access_pde32(guest_pd, fault_addr, error_code); - - // Check the shadow page permissions - shadow_pde_access = v3_can_access_pde32(shadow_pd, fault_addr, error_code); - - /* 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", - *(uint_t *)&guest_pde_access, *(uint_t *)&error_code); - inject_guest_pf(info, fault_addr, error_code); - return 0; - } - - - if (shadow_pde_access == PT_ACCESS_NOT_PRESENT) - { - pte32_t * shadow_pt = (pte32_t *)v3_create_new_shadow_pt(); - - 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 = PAGE_BASE_ADDR((addr_t)V3_PAddr(shadow_pt)); - - if (guest_pde->large_page == 0) { - shadow_pde->writable = guest_pde->writable; - } else { - // ?? What if guest pde is dirty a this point? - ((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 *)V3_VAddr( (void*)(addr_t) BASE_TO_PAGE_ADDR(shadow_pde->pt_base_addr) ); - - if (guest_pde->large_page == 0) { - pte32_t * guest_pt = NULL; - if (guest_pa_to_host_va(info, BASE_TO_PAGE_ADDR(guest_pde->pt_base_addr), (addr_t*)&guest_pt) == -1) { - // Machine check the guest - PrintDebug("Invalid Guest PTE Address: 0x%p\n", (void *)BASE_TO_PAGE_ADDR(guest_pde->pt_base_addr)); - 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_pagefault_32(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_ACCESS_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_ACCESS_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; + if (ret == -1) { + PrintError("Could not read instruction into buffer\n"); + return -1; } - 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; + if (v3_decode(info, (addr_t)instr, &dec_instr) == -1) { + PrintError("Decoding Error\n"); + return -1; } - - PrintDebug("Returning end of PDE function (rip=%p)\n", (void *)(addr_t)(info->rip)); - return 0; -} - - - -/* The guest status checks have already been done, - * only special case shadow checks remain - */ -static int handle_large_pagefault_32(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 = v3_can_access_pte32(shadow_pt, fault_addr, error_code); - pte32_t * shadow_pte = (pte32_t *)&(shadow_pt[PTE32_INDEX(fault_addr)]); - 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_ACCESS_NOT_PRESENT) { - // Get the guest physical address of the fault - addr_t guest_fault_pa = BASE_TO_PAGE_ADDR_4MB(large_guest_pde->page_base_addr) + PAGE_OFFSET_4MB(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%p)\n", (void *)guest_fault_pa); - v3_raise_exception(info, MC_EXCEPTION); - return 0; - } - - if (host_page_type == HOST_REGION_PHYSICAL_MEMORY) { - struct shadow_page_state * state = &(info->shdw_pg_state); - addr_t shadow_pa = get_shadow_addr(info, guest_fault_pa); - - shadow_pte->page_base_addr = PAGE_BASE_ADDR(shadow_pa); - - 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; - - if (find_pte_map(state->cached_ptes, PAGE_ADDR(guest_fault_pa)) != NULL) { - // Check if the entry is a page table... - PrintDebug("Marking page as Guest Page Table (large page)\n"); - shadow_pte->vmm_info = PT32_GUEST_PT; - shadow_pte->writable = 0; - } else { - 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, guest_fault_pa, error_code) == -1) { - PrintError("Special Page Fault handler returned error for address: %p\n", (void *)fault_addr); + 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; - } } - } else if ((shadow_pte_access == PT_ACCESS_WRITE_ERROR) && - (shadow_pte->vmm_info == PT32_GUEST_PT)) { - struct shadow_page_state * state = &(info->shdw_pg_state); - PrintDebug("Write operation on Guest PAge Table Page (large page)\n"); - state->cached_cr3 = 0; - shadow_pte->writable = 1; - - } 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; + 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; + } } -/* - * 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 = v3_can_access_pte32(guest_pt, fault_addr, error_code); - - // Check the shadow page permissions - shadow_pte_access = v3_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_ACCESS_NOT_PRESENT) { +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; - addr_t guest_pa = BASE_TO_PAGE_ADDR((addr_t)(guest_pte->page_base_addr)) + PAGE_OFFSET(fault_addr); + 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)); - // Page Table Entry Not Present - PrintDebug("guest_pa =%p\n", (void *)guest_pa); + list_move(&(page_tail->page_list_node), &(state->page_list)); - host_region_type_t host_page_type = get_shadow_addr_type(info, guest_pa); + memset(V3_VAddr((void *)(page_tail->page_pa)), 0, PAGE_SIZE_4KB); - if (host_page_type == HOST_REGION_INVALID) { - // Inject a machine check in the guest - PrintDebug("Invalid Guest Address in page table (0x%p)\n", (void *)guest_pa); - v3_raise_exception(info, MC_EXCEPTION); - return 0; - } - // else... - - if (host_page_type == HOST_REGION_PHYSICAL_MEMORY) { - struct shadow_page_state * state = &(info->shdw_pg_state); - addr_t shadow_pa = get_shadow_addr(info, guest_pa); - - shadow_pte->page_base_addr = PAGE_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 (find_pte_map(state->cached_ptes, PAGE_ADDR(guest_pa)) != NULL) { - // Check if the entry is a page table... - PrintDebug("Marking page as Guest Page Table %d\n", shadow_pte->writable); - shadow_pte->vmm_info = PT32_GUEST_PT; - } - - 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; - - if (shadow_pte->vmm_info == PT32_GUEST_PT) { - // Well that was quick... - struct shadow_page_state * state = &(info->shdw_pg_state); - PrintDebug("Immediate Write operation on Guest PAge Table Page\n"); - state->cached_cr3 = 0; + return page_tail; } - - } else if ((guest_pte->dirty == 0) && (error_code.write == 0)) { // was = - shadow_pte->writable = 0; - } - - - - } 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: %p\n", (void *)fault_addr); - return -1; - } } - } else if ((shadow_pte_access == PT_ACCESS_WRITE_ERROR) && - (guest_pte->dirty == 0)) { - - PrintDebug("Shadow PTE Write Error\n"); - guest_pte->dirty = 1; - shadow_pte->writable = guest_pte->writable; - - if (shadow_pte->vmm_info == PT32_GUEST_PT) { - struct shadow_page_state * state = &(info->shdw_pg_state); - PrintDebug("Write operation on Guest PAge Table Page\n"); - state->cached_cr3 = 0; - } - - 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; -} - + // 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); -/* 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; - - 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"); - PrintPTE32(first_operand, shadow_pte ); -#endif - - shadow_pte->present = 0; - } - - info->rip += index; - - return 0; + return page_tail; } -/* - - -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; +static int inject_guest_pf(struct guest_info * info, addr_t fault_addr, pf_error_t error_code) { + info->ctrl_regs.cr2 = fault_addr; - 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]); - - 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); - - - 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... - - if (host_page_type == HOST_REGION_PHYSICAL_MEMORY) { +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; + } - 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 ((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...? } - } - return 0; + return 0; } -*/ + +