feat: (vm) memory mapping support: mmap/munmap

[lunaix-os.git] / 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 9e124445de45ce370e74afeb53748b1a1ee19c42..64986190bddf58c85cc5c2cc3c792267d6730151 100644 (file)
--- a/lunaix-os/kernel/asm/x86/pfault.c
+++ b/lunaix-os/kernel/asm/x86/pfault.c
@@ -41,17 +41,17 @@ intr_routine_page_fault(const isr_param* param)
         if (do_kernel(&mapping)) {
             return;
         }
         if (do_kernel(&mapping)) {
             return;
         }

-        goto segv_term;
+        // 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) {
     }
 
     struct mm_region* hit_region = region_get(&__current->mm.regions, ptr);
 
     if (!hit_region) {

-        // Into the void...
+        // 当你凝视深渊时……

         goto segv_term;
     }
 
         goto segv_term;
     }
 

-    x86_pte_t* pte = &PTE_MOUNTED(PD_REFERENCED, ptr >> 12);
+    volatile 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
     if ((*pte & PG_PRESENT)) {
         if ((hit_region->attr & COW_MASK) == COW_MASK) {
             // normal page fault, do COW


@@ -66,10 +66,10 @@ intr_routine_page_fault(const isr_param* param)
         goto segv_term;
     }
 
         goto segv_term;
     }
 

-    if (!(*pte)) {
-        // Invalid location
-        goto segv_term;
-    }
+    // if (!(*pte)) {
+    //     // Invalid location
+    //     goto segv_term;
+    // }

 
     uintptr_t loc = *pte & ~0xfff;
 
 
     uintptr_t loc = *pte & ~0xfff;
 


@@ -78,22 +78,50 @@ intr_routine_page_fault(const isr_param* param)
     if ((hit_region->attr & REGION_WRITE) && (*pte & 0xfff) && !loc) {
         cpu_invplg(pte);
         uintptr_t pa = pmm_alloc_page(__current->pid, 0);
     if ((hit_region->attr & REGION_WRITE) && (*pte & 0xfff) && !loc) {
         cpu_invplg(pte);
         uintptr_t pa = pmm_alloc_page(__current->pid, 0);

+        if (!pa) {
+            goto oom;
+        }
+

         *pte = *pte | pa | PG_PRESENT;
         goto resolved;
     }
 
         *pte = *pte | pa | PG_PRESENT;
         goto resolved;
     }
 

+    // if mfile is set, then it is a mem map
+    if (hit_region->mfile) {
+        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;
+        }
+
+        cpu_invplg(pte);
+        *pte = *pte | pa | PG_PRESENT;
+        int errno = file->ops->read_page(
+          file->inode, ptr & (PG_SIZE - 1), 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
     __print_panic_msg("WIP page fault route", param);
     while (1)
         ;
 
     // page not present, bring it from disk or somewhere else
     __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->cs,
             param->eip);
 segv_term:
     kprintf(KERROR "(pid: %d) Segmentation fault on %p (%p:%p)\n",
             __current->pid,
             ptr,
             param->cs,
             param->eip);

-    signal_send(__current->pid, _SIGSEGV);
+    __SIGSET(__current->sig_pending, _SIGSEGV);

     schedule();
     // should not reach
     while (1)
     schedule();
     // should not reach
     while (1)


@@ -108,14 +136,8 @@ int
 do_kernel(v_mapping* mapping)
 {
     uintptr_t addr = mapping->va;
 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:
 
     return 0;
 done: