X-Git-Url: https://scm.lunaixsky.com/lunaix-os.git/blobdiff_plain/728194869c3dc89b0e1c625480d486ada309ae40..620a2ee90a60979955c318cc1b37741184137bd6:/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 index 34589cb..fcf3739 100644 --- a/lunaix-os/kernel/asm/x86/pfault.c +++ b/lunaix-os/kernel/asm/x86/pfault.c @@ -1,5 +1,6 @@ #include #include +#include #include #include #include @@ -17,6 +18,8 @@ kprintf(const char* fmt, ...) va_end(args); } +#define COW_MASK (REGION_RSHARED | REGION_READ | REGION_WRITE) + extern void __print_panic_msg(const char* msg, const isr_param* param); @@ -48,17 +51,16 @@ intr_routine_page_fault(const isr_param* param) goto segv_term; } - x86_pte_t* pte = PTE_MOUNTED(PD_REFERENCED, ptr >> 12); - if (*pte & PG_PRESENT) { - if ((hit_region->attr & REGION_PERM_MASK) == - (REGION_RSHARED | REGION_READ)) { + x86_pte_t* pte = &PTE_MOUNTED(PD_REFERENCED, ptr >> 12); + if ((*pte & PG_PRESENT)) { + 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) | pa | PG_WRITE; - return; + goto resolved; } // impossible cases or accessing privileged page goto segv_term; @@ -68,15 +70,18 @@ intr_routine_page_fault(const isr_param* param) // Invalid location goto segv_term; } + uintptr_t loc = *pte & ~0xfff; - // a writable page, not present, pte attr is not null - // and no indication of cached page -> a new page need to be alloc + + // a writable page, not present, not cached, pte attr is not null + // -> a new page need to be alloc if ((hit_region->attr & REGION_WRITE) && (*pte & 0xfff) && !loc) { cpu_invplg(pte); uintptr_t pa = pmm_alloc_page(__current->pid, 0); *pte = *pte | pa | PG_PRESENT; - return; + goto resolved; } + // page not present, bring it from disk or somewhere else __print_panic_msg("WIP page fault route", param); while (1) @@ -88,8 +93,15 @@ segv_term: ptr, param->cs, param->eip); - terminate_proc(LXSEGFAULT); + __SIGSET(__current->sig_pending, _SIGSEGV); + schedule(); // should not reach + while (1) + ; + +resolved: + cpu_invplg(ptr); + return; } int