X-Git-Url: https://scm.lunaixsky.com/lunaix-os.git/blobdiff_plain/9d62069fd52fa2108b677ffadc7f6138c7641757..f13e160f6aa2f74895ecf1f65099265643836210:/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 6df3182..7b8a12b 100644 --- a/lunaix-os/kernel/asm/x86/pfault.c +++ b/lunaix-os/kernel/asm/x86/pfault.c @@ -1,14 +1,16 @@ #include #include -#include #include #include #include #include #include +#include #include #include +#include + static void kprintf(const char* fmt, ...) { @@ -52,7 +54,7 @@ intr_routine_page_fault(const isr_param* param) } volatile x86_pte_t* pte = &PTE_MOUNTED(PD_REFERENCED, ptr >> 12); - if ((*pte & PG_PRESENT)) { + if (PG_PRESENTED(*pte)) { if ((hit_region->attr & COW_MASK) == COW_MASK) { // normal page fault, do COW cpu_invplg(pte); @@ -66,27 +68,56 @@ intr_routine_page_fault(const isr_param* param) goto segv_term; } - if (!(*pte)) { - // Invalid location + // an anonymous page and not present + // -> a new page need to be alloc + if ((hit_region->attr & REGION_ANON)) { + if (!PG_PRESENTED(*pte)) { + cpu_invplg(pte); + uintptr_t pa = pmm_alloc_page(__current->pid, 0); + if (!pa) { + goto oom; + } + + *pte = *pte | pa | PG_PRESENT; + goto resolved; + } + // permission denied on anon page goto segv_term; } - uintptr_t loc = *pte & ~0xfff; + // if mfile is set (Non-anonymous), then it is a mem map + if (hit_region->mfile && !PG_PRESENTED(*pte)) { + struct v_file* file = hit_region->mfile; + u32_t offset = + (ptr - hit_region->start) & (PG_SIZE - 1) + hit_region->offset; + uintptr_t pa = pmm_alloc_page(__current->pid, 0); + + if (!pa) { + goto oom; + } - // 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; + *pte = (*pte & 0xFFF) | pa | PG_PRESENT; + + ptr = ptr & ~(PG_SIZE - 1); + memset(ptr, 0, PG_SIZE); + + int errno = file->ops->read_page(file->inode, ptr, PG_SIZE, offset); + if (errno < 0) { + kprintf(KERROR "fail to read page (%d)\n", errno); + goto segv_term; + } + goto resolved; } - // page not present, bring it from disk or somewhere else + // 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, @@ -108,14 +139,8 @@ int do_kernel(v_mapping* mapping) { uintptr_t addr = mapping->va; - if (addr >= KHEAP_START && addr < PROC_START) { - // This is kernel heap page - uintptr_t pa = pmm_alloc_page(KERNEL_PID, 0); - *mapping->pte = (*mapping->pte & 0xfff) | pa | PG_PRESENT; - cpu_invplg(mapping->pte); - cpu_invplg(addr); - goto done; - } + + // TODO return 0; done: