X-Git-Url: https://scm.lunaixsky.com/lunaix-os.git/blobdiff_plain/8c6f505faaa66e18cdca108dca549d4ad806a077..b91be0033265b5b6bd716bd39cb0971da41906c4:/lunaix-os/kernel/asm/x86/pfault.c diff --git a/lunaix-os/kernel/asm/x86/pfault.c b/lunaix-os/kernel/asm/x86/pfault.c deleted file mode 100644 index 610c1cb..0000000 --- a/lunaix-os/kernel/asm/x86/pfault.c +++ /dev/null @@ -1,158 +0,0 @@ -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#include - -static void -kprintf(const char* fmt, ...) -{ - va_list args; - va_start(args, fmt); - __kprintf("PFAULT", fmt, args); - va_end(args); -} - -#define COW_MASK (REGION_RSHARED | REGION_READ | REGION_WRITE) - -extern void -__print_panic_msg(const char* msg, const isr_param* param); - -void -intr_routine_page_fault(const isr_param* param) -{ - uintptr_t ptr = cpu_rcr2(); - if (!ptr) { - goto segv_term; - } - - v_mapping mapping; - if (!vmm_lookup(ptr, &mapping)) { - goto segv_term; - } - - if (!SEL_RPL(param->execp->cs)) { - // 如果是内核页错误…… - if (do_kernel(&mapping)) { - return; - } - // 如果不是,那么看看内核是不是需要用户页。 - } - - struct mm_region* hit_region = region_get(&__current->mm.regions, ptr); - - if (!hit_region) { - // 当你凝视深渊时…… - goto segv_term; - } - - volatile x86_pte_t* pte = &PTE_MOUNTED(VMS_SELF, ptr >> 12); - if (PG_IS_PRESENT(*pte)) { - if ((hit_region->attr & COW_MASK) == COW_MASK) { - // normal page fault, do COW - cpu_invplg(pte); - uintptr_t pa = - (uintptr_t)vmm_dup_page(__current->pid, PG_ENTRY_ADDR(*pte)); - pmm_free_page(__current->pid, *pte & ~0xFFF); - *pte = (*pte & 0xFFF & ~PG_DIRTY) | pa | PG_WRITE; - goto resolved; - } - // impossible cases or accessing privileged page - goto segv_term; - } - - // an anonymous page and not present - // -> a new page need to be alloc - if ((hit_region->attr & REGION_ANON)) { - if (!PG_IS_PRESENT(*pte)) { - cpu_invplg(pte); - uintptr_t pa = pmm_alloc_page(__current->pid, 0); - if (!pa) { - goto oom; - } - - *pte = *pte | pa | PG_PRESENT; - memset(PG_ALIGN(ptr), 0, PG_SIZE); - goto resolved; - } - // permission denied on anon page (e.g., write on readonly page) - goto segv_term; - } - - // if mfile is set (Non-anonymous), then it is a mem map - if (hit_region->mfile && !PG_IS_PRESENT(*pte)) { - struct v_file* file = hit_region->mfile; - - ptr = PG_ALIGN(ptr); - - u32_t offset = (ptr - hit_region->start) + hit_region->foff; - uintptr_t pa = pmm_alloc_page(__current->pid, 0); - - if (!pa) { - goto oom; - } - - cpu_invplg(pte); - *pte = (*pte & 0xFFF) | pa | PG_PRESENT; - - memset(ptr, 0, PG_SIZE); - - int errno = 0; - if (hit_region->init_page) { - errno = hit_region->init_page(hit_region, ptr, offset); - } else { - errno = file->ops->read_page(file->inode, ptr, PG_SIZE, offset); - } - - if (errno < 0) { - kprintf(KERROR "fail to populate page (%d)\n", errno); - goto segv_term; - } - - *pte &= ~PG_DIRTY; - - goto resolved; - } - - // page not present, might be a chance to introduce swap file? - __print_panic_msg("WIP page fault route", param); - while (1) - ; - -oom: - kprintf(KERROR "out of memory\n"); -segv_term: - kprintf(KERROR "(pid: %d) Segmentation fault on %p (%p:%p)\n", - __current->pid, - ptr, - param->execp->cs, - param->execp->eip); - __SIGSET(__current->sig_pending, _SIGSEGV); - schedule(); - // should not reach - while (1) - ; - -resolved: - cpu_invplg(ptr); - return; -} - -int -do_kernel(v_mapping* mapping) -{ - uintptr_t addr = mapping->va; - - // TODO - - return 0; -done: - return 1; -} \ No newline at end of file