X-Git-Url: http://v3vee.org/palacios/gitweb/gitweb.cgi?a=blobdiff_plain;f=palacios%2Fsrc%2Fpalacios%2Fvmm_shadow_paging.c;h=05d913d9193493eb71dd8ebe60b0c435cbf61e13;hb=101529b6eae500272347287df43ec51aa003d0aa;hp=9e70bb2ac040a3dbe79456b79fb98998e7e40a6b;hpb=a5c5675571882a9b8a7594ef07fe303b195ef9ae;p=palacios.git diff --git a/palacios/src/palacios/vmm_shadow_paging.c b/palacios/src/palacios/vmm_shadow_paging.c index 9e70bb2..05d913d 100644 --- a/palacios/src/palacios/vmm_shadow_paging.c +++ b/palacios/src/palacios/vmm_shadow_paging.c @@ -1,3 +1,7 @@ +/* (c) 2008, Jack Lange */ +/* (c) 2008, The V3VEE Project */ + + #include @@ -18,6 +22,36 @@ + +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 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 handle_shadow_pte32_fault(struct guest_info* info, addr_t fault_addr, pf_error_t error_code, @@ -34,9 +68,145 @@ int init_shadow_page_state(struct guest_info * info) { state->guest_cr3 = 0; state->shadow_cr3 = 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); + + + 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 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; + + 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_pa(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_pa(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_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(info->shdw_pg_state.shadow_cr3); + pde32_t * shadow_pde = (pde32_t *)&(shadow_pd[PDE32_INDEX(location)]); + + if (shadow_pde->large_page == 0) { + pte32_t * shadow_pt = (pte32_t *)PDE32_T_ADDR((*shadow_pde)); + 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 + return -1; + } + return 0; } + + + + + int handle_shadow_pagefault(struct guest_info * info, addr_t fault_addr, pf_error_t error_code) { if (info->mem_mode == PHYSICAL_MEM) { @@ -142,6 +312,7 @@ static int handle_large_pagefault32(struct guest_info * info, } 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 = PT32_BASE_ADDR(shadow_pa); @@ -154,7 +325,16 @@ static int handle_large_pagefault32(struct guest_info * info, * Allow everything */ shadow_pte->user_page = 1; - shadow_pte->writable = 1; + + if (find_pte_map(state->cached_ptes, PT32_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; @@ -164,11 +344,19 @@ static int handle_large_pagefault32(struct guest_info * info, } else { // Handle hooked pages as well as other special pages - if (handle_special_page_fault(info, fault_addr, PT32_PAGE_ADDR(guest_fault_pa), error_code) == -1) { + if (handle_special_page_fault(info, fault_addr, guest_fault_pa, error_code) == -1) { PrintError("Special Page Fault handler returned error for address: %x\n", fault_addr); return -1; } } + } else if ((shadow_pte_access == PT_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"); @@ -276,6 +464,7 @@ static int handle_shadow_pagefault32(struct guest_info * info, addr_t fault_addr // 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; @@ -361,7 +550,7 @@ static int handle_shadow_pte32_fault(struct guest_info * info, if (shadow_pte_access == PT_ENTRY_NOT_PRESENT) { - addr_t guest_pa = PTE32_T_ADDR((*guest_pte)); + addr_t guest_pa = PTE32_T_ADDR((*guest_pte)) + PT32_PAGE_OFFSET(fault_addr); // Page Table Entry Not Present @@ -377,6 +566,7 @@ static int handle_shadow_pte32_fault(struct guest_info * info, // 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 = PT32_BASE_ADDR(shadow_pa); @@ -392,14 +582,31 @@ static int handle_shadow_pte32_fault(struct guest_info * info, guest_pte->accessed = 1; + if (find_pte_map(state->cached_ptes, PT32_PAGE_ADDR(guest_pa)) != NULL) { + // Check if the entry is a page table... + PrintDebug("Marking page as Guest Page Table\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; + } + } else if ((guest_pte->dirty = 0) && (error_code.write == 0)) { shadow_pte->writable = 0; } + + + } else { // Page fault handled by hook functions if (handle_special_page_fault(info, fault_addr, guest_pa, error_code) == -1) { @@ -414,6 +621,13 @@ static int handle_shadow_pte32_fault(struct guest_info * info, 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 {