#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
***/
-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);
+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);
-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);
+#include "vmm_shadow_paging_32.h"
+#include "vmm_shadow_paging_32pae.h"
+#include "vmm_shadow_paging_64.h"
-static uint_t pte_hash_fn(addr_t key) {
- return hash_long(key, 32);
+#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);
}
-
-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);
-}
-
-
-
-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);
+#endif
-static int cache_page_tables_32(struct guest_info * info, addr_t pde);
-static int cache_page_tables_64(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;
+ state->guest_cr3 = 0;
+ state->guest_cr0 = 0;
+ state->guest_efer.value = 0x0LL;
- 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);
+ 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)(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;
-
-}
-
-
-static int cache_page_tables_64(struct guest_info * info, addr_t pde) {
- return -1;
-}
-
-
-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;
-}
-
-static int activate_shadow_pt_64_cb(page_type_t type, addr_t vaddr, addr_t page_ptr, addr_t page_pa, void * private_data) {
- PrintDebug("CB: Page: %p->%p (host_ptr=%p), Type: %s\n", (void *)vaddr, (void *)page_pa, (void *)page_ptr, v3_page_type_to_str(type));
- return 0;
+ 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;
-
- v3_walk_guest_pt_64(info, info->shdw_pg_state.guest_cr3, activate_shadow_pt_64_cb, NULL);
-
-
-
- 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->pml4t_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->pml4t_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
- 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;
- }
}
-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) {
- 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 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);
+ if (ret == -1) {
+ PrintError("Could not read instruction into buffer\n");
+ return -1;
+ }
- PrintDebug("Shadow Access Check: %d (access=%d)\n", ret, shadow_access);
+ 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;
+ }
- 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;
+ 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 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 *)(addr_t)page_tail->page_pa,
+ (void *)(addr_t)cur_cr3,
+ (void *)(addr_t)(page_tail->cr3));
+ list_move(&(page_tail->page_list_node), &(state->page_list));
-/*
- * *
- * *
- * * 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;
- }
+ memset(V3_VAddr((void *)(page_tail->page_pa)), 0, PAGE_SIZE_4KB);
-
- 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) {
- pte32_t * guest_pt = NULL;
- shadow_pde->writable = guest_pde->writable;
-
- 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;
+ return page_tail;
}
- } 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;
- }
- 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);
- PrintPTEntry(PAGE_PD32, fault_addr, guest_pde);
- PrintDebug("Shadow PDE: (access=%d)\n\t", shadow_pde_access);
- PrintPTEntry(PAGE_PD32, fault_addr, shadow_pde);
-#endif
- return 0;
- }
-
- 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)]);
- addr_t guest_fault_pa = BASE_TO_PAGE_ADDR_4MB(large_guest_pde->page_base_addr) + PAGE_OFFSET_4MB(fault_addr);
-
- struct v3_shadow_region * shdw_reg = v3_get_shadow_region(info, guest_fault_pa);
-
-
- if ((shdw_reg == NULL) ||
- (shdw_reg->host_type == SHDW_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 -1;
- }
-
- 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;
- }
+ // else
-
- if (shadow_pte_access == PT_ACCESS_NOT_PRESENT) {
- // Get the guest physical address of the fault
-
- if ((shdw_reg->host_type == SHDW_REGION_ALLOCATED) ||
- (shdw_reg->host_type == SHDW_REGION_WRITE_HOOK)) {
- struct shadow_page_state * state = &(info->shdw_pg_state);
- addr_t shadow_pa = v3_get_shadow_addr(shdw_reg, 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 if (shdw_reg->host_type == SHDW_REGION_WRITE_HOOK) {
- 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) {
+ page_tail = (struct shadow_page_data *)V3_Malloc(sizeof(struct shadow_page_data));
+ page_tail->page_pa = (addr_t)V3_AllocPages(1);
- if (v3_handle_mem_full_hook(info, fault_addr, guest_fault_pa, shdw_reg, 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) {
+ PrintDebug("Allocating new shadow Page: %p (cur_cr3=%p)\n",
+ (void *)(addr_t)page_tail->page_pa,
+ (void *)(addr_t)cur_cr3);
- if (shdw_reg->host_type == SHDW_REGION_WRITE_HOOK) {
+ page_tail->cr3 = cur_cr3;
+ list_add(&(page_tail->page_list_node), &(state->page_list));
- if (v3_handle_mem_wr_hook(info, fault_addr, guest_fault_pa, shdw_reg, error_code) == -1) {
- PrintError("Special Page Fault handler returned error for address: %p\n", (void *)fault_addr);
- return -1;
- }
- } else 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 (large page)\n");
- state->cached_cr3 = 0;
- shadow_pte->writable = 1;
- }
+ shdw_page = (addr_t)V3_VAddr((void *)(page_tail->page_pa));
+ memset((void *)shdw_page, 0, PAGE_SIZE_4KB);
- } 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;
+ return page_tail;
}
+static int inject_guest_pf(struct guest_info * info, addr_t fault_addr, pf_error_t error_code) {
+ info->ctrl_regs.cr2 = fault_addr;
-
-/*
- * 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)]);
- addr_t guest_pa = BASE_TO_PAGE_ADDR((addr_t)(guest_pte->page_base_addr)) + PAGE_OFFSET(fault_addr);
-
- struct v3_shadow_region * shdw_reg = v3_get_shadow_region(info, guest_pa);
-
- if ((shdw_reg == NULL) ||
- (shdw_reg->host_type == SHDW_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;
- }
-
- // 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);
- PrintPTEntry(PAGE_PT32, fault_addr, guest_pte);
- PrintDebug("Shadow PTE: (access=%d)\n\t", shadow_pte_access);
- PrintPTEntry(PAGE_PT32, fault_addr, shadow_pte);
+#ifdef CONFIG_SHADOW_PAGING_TELEMETRY
+ info->shdw_pg_state.guest_faults++;
#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) {
- // Page Table Entry Not Present
- PrintDebug("guest_pa =%p\n", (void *)guest_pa);
-
- if ((shdw_reg->host_type == SHDW_REGION_ALLOCATED) ||
- (shdw_reg->host_type == SHDW_REGION_WRITE_HOOK)) {
- struct shadow_page_state * state = &(info->shdw_pg_state);
- addr_t shadow_pa = v3_get_shadow_addr(shdw_reg, 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 (shdw_reg->host_type == SHDW_REGION_WRITE_HOOK) {
- shadow_pte->writable = 0;
- } else 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;
- }
- } else if ((guest_pte->dirty == 0) && (error_code.write == 0)) { // was =
- shadow_pte->writable = 0;
- }
+ return v3_raise_exception_with_error(info, PF_EXCEPTION, *(uint_t *)&error_code);
+}
- } else {
- // Page fault handled by hook functions
- if (v3_handle_mem_full_hook(info, fault_addr, guest_pa, shdw_reg, 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)) {
+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...
*/
- } else if (shadow_pte_access == PT_ACCESS_WRITE_ERROR) {
- guest_pte->dirty = 1;
+ if (guest_access != PT_ACCESS_OK) {
+ // Guest Access Error
- if (shdw_reg->host_type == SHDW_REGION_WRITE_HOOK) {
- if (v3_handle_mem_wr_hook(info, fault_addr, guest_pa, shdw_reg, error_code) == -1) {
- PrintError("Special Page fault handler returned error for address: %p\n", (void *)fault_addr);
- return -1;
- }
- } else {
- PrintDebug("Shadow PTE Write Error\n");
- shadow_pte->writable = guest_pte->writable;
- }
+ if ((shadow_access != PT_ACCESS_NOT_PRESENT) &&
+ (guest_access != PT_ACCESS_NOT_PRESENT)) {
+ // aka (guest permission error)
+ return 1;
+ }
- 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;
+ /*
+ 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;
-
- } 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;
-}
-
-
-
-
-
-
-/* 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");
- PrintPTEntry(PAGE_PT32, first_operand, shadow_pte);
-#endif
-
- shadow_pte->present = 0;
- }
-
- info->rip += index;
-
- return 0;
}
