X-Git-Url: http://v3vee.org/palacios/gitweb/gitweb.cgi?a=blobdiff_plain;f=palacios%2Fsrc%2Fpalacios%2Fvmm_shadow_paging.c;h=e6bad8a470ae9a2ab1bca5bd96f58398be430bac;hb=ae2948e2c649d8e63252d4b665f29b268858294e;hp=0f98acf733dcb60b1e6750eb9c175e13fa9be03b;hpb=42fa79cec8ed9c44392a71c6253edab3abcb900e;p=palacios.git diff --git a/palacios/src/palacios/vmm_shadow_paging.c b/palacios/src/palacios/vmm_shadow_paging.c index 0f98acf..e6bad8a 100644 --- a/palacios/src/palacios/vmm_shadow_paging.c +++ b/palacios/src/palacios/vmm_shadow_paging.c @@ -39,34 +39,14 @@ ***/ -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); @@ -81,7 +61,7 @@ static int pte_equals(addr_t key1, addr_t key2) { return (key1 == key2); } -static addr_t create_new_shadow_pt(); +static addr_t create_new_shadow_pt(struct guest_info * info); static void inject_guest_pf(struct guest_info * info, addr_t fault_addr, pf_error_t error_code); static int is_guest_pf(pt_access_status_t guest_access, pt_access_status_t shadow_access); @@ -98,6 +78,8 @@ int v3_init_shadow_page_state(struct guest_info * info) { state->guest_cr3 = 0; state->guest_cr0 = 0; + INIT_LIST_HEAD(&(state->page_list)); + state->cached_ptes = NULL; state->cached_cr3 = 0; @@ -168,67 +150,6 @@ int v3_handle_shadow_pagefault(struct guest_info * info, addr_t fault_addr, pf_e } - -static addr_t create_new_shadow_pt() { - void * host_pde = 0; - - host_pde = V3_VAddr(V3_AllocPages(1)); - memset(host_pde, 0, PAGE_SIZE); - - 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 ((shadow_access == PT_ACCESS_NOT_PRESENT) && - (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; -} - - - - - - - - - - int v3_handle_shadow_invlpg(struct guest_info * info) { uchar_t instr[15]; struct x86_instr dec_instr; @@ -284,3 +205,83 @@ int v3_handle_shadow_invlpg(struct guest_info * info) { } } + + + +static addr_t 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) { + page_tail->cr3 = cur_cr3; + list_move(&(page_tail->page_list_node), &(state->page_list)); + + memset(V3_VAddr((void *)(page_tail->page_pa)), 0, PAGE_SIZE_4KB); + PrintDebug("Reusing old shadow Page\n"); + + return (addr_t)V3_VAddr((void *)(page_tail->page_pa)); + } + } + + // else + + page_tail = (struct shadow_page_data *)V3_Malloc(sizeof(struct shadow_page_data)); + page_tail->page_pa = (addr_t)V3_AllocPages(1); + + 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 shdw_page; +} + + +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 ((shadow_access == PT_ACCESS_NOT_PRESENT) && + (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; +} + +