feat: No more kernel page table switching upon interrupt.

[lunaix-os.git] / lunaix-os / kernel / mm / vmm.c

diff --git a/lunaix-os/kernel/mm/vmm.c b/lunaix-os/kernel/mm/vmm.c
index 0aa09b8ee6c33fc942e66ed06f768c64f57f8e11..5e407ff52915656a412eabb3c4a837e1c9d1b8a3 100644 (file)
--- a/lunaix-os/kernel/mm/vmm.c
+++ b/lunaix-os/kernel/mm/vmm.c
@@ -1,7 +1,5 @@
 #include <hal/cpu.h>
 #include <klibc/string.h>
 #include <hal/cpu.h>
 #include <klibc/string.h>

-#include <lunaix/mm/page.h>
-#include <lunaix/mm/pmm.h>

 #include <lunaix/mm/vmm.h>
 #include <lunaix/spike.h>
 
 #include <lunaix/mm/vmm.h>
 #include <lunaix/spike.h>
 


@@ -16,7 +14,7 @@ vmm_init()
 x86_page_table*
 vmm_init_pd()
 {
 x86_page_table*
 vmm_init_pd()
 {

-    x86_page_table* dir = (x86_page_table*)pmm_alloc_page();
+    x86_page_table* dir = (x86_page_table*)pmm_alloc_page(KERNEL_PID, PP_FGPERSIST);

     for (size_t i = 0; i < PG_MAX_ENTRIES; i++) {
         dir->entry[i] = PTE_NULL;
     }
     for (size_t i = 0; i < PG_MAX_ENTRIES; i++) {
         dir->entry[i] = PTE_NULL;
     }


@@ -28,7 +26,8 @@ vmm_init_pd()
 }
 
 int
 }
 
 int

-__vmm_map_internal(uint32_t l1_inx,
+__vmm_map_internal(pid_t pid, 
+                   uint32_t l1_inx,

                    uint32_t l2_inx,
                    uintptr_t pa,
                    pt_attr attr,
                    uint32_t l2_inx,
                    uintptr_t pa,
                    pt_attr attr,


@@ -41,14 +40,15 @@ __vmm_map_internal(uint32_t l1_inx,
     assert(attr <= 128);
 
     if (!l1pt->entry[l1_inx]) {
     assert(attr <= 128);
 
     if (!l1pt->entry[l1_inx]) {

-        x86_page_table* new_l1pt_pa = pmm_alloc_page();
+        x86_page_table* new_l1pt_pa = pmm_alloc_page(pid, PP_FGPERSIST);

 
         // 物理内存已满！
         if (!new_l1pt_pa) {
             return 0;
         }
 
 
         // 物理内存已满！
         if (!new_l1pt_pa) {
             return 0;
         }
 

-        l1pt->entry[l1_inx] = NEW_L1_ENTRY(attr, new_l1pt_pa);
+        // This must be writable
+        l1pt->entry[l1_inx] = NEW_L1_ENTRY(attr | PG_WRITE, new_l1pt_pa);

         memset((void*)L2_VADDR(l1_inx), 0, PG_SIZE);
     }
 
         memset((void*)L2_VADDR(l1_inx), 0, PG_SIZE);
     }
 


@@ -57,9 +57,11 @@ __vmm_map_internal(uint32_t l1_inx,
         if (!forced) {
             return 0;
         }
         if (!forced) {
             return 0;
         }

-        if (HAS_FLAGS(l2pte, PG_PRESENT)) {
-            assert_msg(pmm_free_page(GET_PG_ADDR(l2pte)), "fail to release physical page");
-        }
+    }
+
+    if ((HAS_FLAGS(attr, PG_PRESENT))) {
+        // add one on reference count, regardless of existence.
+        pmm_ref_page(pid, pa);

     }
 
     l2pt->entry[l2_inx] = NEW_L2_ENTRY(attr, pa);
     }
 
     l2pt->entry[l2_inx] = NEW_L2_ENTRY(attr, pa);


@@ -68,7 +70,7 @@ __vmm_map_internal(uint32_t l1_inx,
 }
 
 void*
 }
 
 void*

-vmm_map_page(void* va, void* pa, pt_attr tattr)
+vmm_map_page(pid_t pid, void* va, void* pa, pt_attr tattr)

 {
     // 显然，对空指针进行映射没有意义。
     if (!pa || !va) {
 {
     // 显然，对空指针进行映射没有意义。
     if (!pa || !va) {


@@ -92,8 +94,7 @@ vmm_map_page(void* va, void* pa, pt_attr tattr)
             l2pt = (x86_page_table*)L2_VADDR(l1_index);
         }
         // 页表有空位，只需要开辟一个新的 PTE (Level 2)
             l2pt = (x86_page_table*)L2_VADDR(l1_index);
         }
         // 页表有空位，只需要开辟一个新的 PTE (Level 2)

-        if (l2pt && !l2pt->entry[l2_index]) {
-            l2pt->entry[l2_index] = NEW_L2_ENTRY(tattr, pa);
+        if (__vmm_map_internal(pid, l1_index, l2_index, pa, tattr, false)) {

             return (void*)V_ADDR(l1_index, l2_index, PG_OFFSET(va));
         }
         l2_index++;
             return (void*)V_ADDR(l1_index, l2_index, PG_OFFSET(va));
         }
         l2_index++;


@@ -104,7 +105,7 @@ vmm_map_page(void* va, void* pa, pt_attr tattr)
         return NULL;
     }
 
         return NULL;
     }
 

-    if (!__vmm_map_internal(l1_index, l2_index, (uintptr_t)pa, tattr, false)) {
+    if (!__vmm_map_internal(pid, l1_index, l2_index, (uintptr_t)pa, tattr, false)) {

         return NULL;
     }
 
         return NULL;
     }
 


@@ -112,7 +113,7 @@ vmm_map_page(void* va, void* pa, pt_attr tattr)
 }
 
 void*
 }
 
 void*

-vmm_fmap_page(void* va, void* pa, pt_attr tattr)
+vmm_fmap_page(pid_t pid, void* va, void* pa, pt_attr tattr)

 {
     if (!pa || !va) {
         return NULL;
 {
     if (!pa || !va) {
         return NULL;


@@ -123,42 +124,44 @@ vmm_fmap_page(void* va, void* pa, pt_attr tattr)
     uint32_t l1_index = L1_INDEX(va);
     uint32_t l2_index = L2_INDEX(va);
 
     uint32_t l1_index = L1_INDEX(va);
     uint32_t l2_index = L2_INDEX(va);
 

-    if (!__vmm_map_internal(l1_index, l2_index, (uintptr_t)pa, tattr, true)) {
+    if (!__vmm_map_internal(pid, l1_index, l2_index, (uintptr_t)pa, tattr, true)) {

         return NULL;
     }
 
     cpu_invplg(va);
 
         return NULL;
     }
 
     cpu_invplg(va);
 

-    return (void*)V_ADDR(l1_index, l2_index, PG_OFFSET(va));
+    return va;

 }
 
 void*
 }
 
 void*

-vmm_alloc_page(void* vpn, pt_attr tattr)
+vmm_alloc_page(pid_t pid, void* vpn, void** pa, pt_attr tattr, pp_attr_t pattr)

 {
 {

-    void* pp = pmm_alloc_page();
-    void* result = vmm_map_page(vpn, pp, tattr);
+    void* pp = pmm_alloc_page(pid, pattr);
+    void* result = vmm_map_page(pid, vpn, pp, tattr);

     if (!result) {
     if (!result) {

-        pmm_free_page(pp);
+        pmm_free_page(pp, pid);

     }
     }

+    pa ? (*pa = pp) : 0;

     return result;
 }
 
 int
     return result;
 }
 
 int

-vmm_alloc_pages(void* va, size_t sz, pt_attr tattr)
+vmm_alloc_pages(pid_t pid, void* va, size_t sz, pt_attr tattr, pp_attr_t pattr)

 {
     assert((uintptr_t)va % PG_SIZE == 0) assert(sz % PG_SIZE == 0);
 
     void* va_ = va;
     for (size_t i = 0; i < (sz >> PG_SIZE_BITS); i++, va_ += PG_SIZE) {
 {
     assert((uintptr_t)va % PG_SIZE == 0) assert(sz % PG_SIZE == 0);
 
     void* va_ = va;
     for (size_t i = 0; i < (sz >> PG_SIZE_BITS); i++, va_ += PG_SIZE) {

-        void* pp = pmm_alloc_page();
+        void* pp = pmm_alloc_page(pid, pattr);

         uint32_t l1_index = L1_INDEX(va_);
         uint32_t l2_index = L2_INDEX(va_);
         if (!pp || !__vmm_map_internal(
         uint32_t l1_index = L1_INDEX(va_);
         uint32_t l2_index = L2_INDEX(va_);
         if (!pp || !__vmm_map_internal(

+                     pid,

                      l1_index, l2_index, (uintptr_t)pp, tattr, false)) {
             // if one failed, release previous allocated pages.
             va_ = va;
             for (size_t j = 0; j < i; j++, va_ += PG_SIZE) {
                      l1_index, l2_index, (uintptr_t)pp, tattr, false)) {
             // if one failed, release previous allocated pages.
             va_ = va;
             for (size_t j = 0; j < i; j++, va_ += PG_SIZE) {

-                vmm_unmap_page(va_);
+                vmm_unmap_page(pid, va_);

             }
 
             return false;
             }
 
             return false;


@@ -168,8 +171,8 @@ vmm_alloc_pages(void* va, size_t sz, pt_attr tattr)
     return true;
 }
 
     return true;
 }
 

-void
-vmm_set_mapping(void* va, void* pa, pt_attr attr) {
+int
+vmm_set_mapping(pid_t pid, void* va, void* pa, pt_attr attr) {

     assert(((uintptr_t)va & 0xFFFU) == 0);
 
     uint32_t l1_index = L1_INDEX(va);
     assert(((uintptr_t)va & 0xFFFU) == 0);
 
     uint32_t l1_index = L1_INDEX(va);


@@ -177,15 +180,15 @@ vmm_set_mapping(void* va, void* pa, pt_attr attr) {
 
     // prevent map of recursive mapping region
     if (l1_index == 1023) {
 
     // prevent map of recursive mapping region
     if (l1_index == 1023) {

-        return;
+        return 0;

     }
     
     }
     

-    __vmm_map_internal(l1_index, l2_index, (uintptr_t)pa, attr, false);
+    __vmm_map_internal(pid, l1_index, l2_index, (uintptr_t)pa, attr, false);
+    return 1;

 }
 
 void
 }
 
 void

-vmm_unmap_page(void* va)
-{
+__vmm_unmap_internal(pid_t pid, void* va, int free_ppage) {

     assert(((uintptr_t)va & 0xFFFU) == 0);
 
     uint32_t l1_index = L1_INDEX(va);
     assert(((uintptr_t)va & 0xFFFU) == 0);
 
     uint32_t l1_index = L1_INDEX(va);


@@ -203,14 +206,25 @@ vmm_unmap_page(void* va)
     if (l1pte) {
         x86_page_table* l2pt = (x86_page_table*)L2_VADDR(l1_index);
         x86_pte_t l2pte = l2pt->entry[l2_index];
     if (l1pte) {
         x86_page_table* l2pt = (x86_page_table*)L2_VADDR(l1_index);
         x86_pte_t l2pte = l2pt->entry[l2_index];

-        if (IS_CACHED(l2pte)) {
-            pmm_free_page((void*)l2pte);
+        if (IS_CACHED(l2pte) && free_ppage) {
+            pmm_free_page(pid, (void*)l2pte);

         }
         cpu_invplg(va);
         l2pt->entry[l2_index] = PTE_NULL;
     }
 }
 
         }
         cpu_invplg(va);
         l2pt->entry[l2_index] = PTE_NULL;
     }
 }
 

+void
+vmm_unset_mapping(void* va) {
+    __vmm_unmap_internal(0, va, false);
+}
+
+void
+vmm_unmap_page(pid_t pid, void* va)
+{
+    __vmm_unmap_internal(pid, va, true);
+}
+

 v_mapping
 vmm_lookup(void* va)
 {
 v_mapping
 vmm_lookup(void* va)
 {


@@ -224,12 +238,13 @@ vmm_lookup(void* va)
 
     v_mapping mapping = { .flags = 0, .pa = 0, .pn = 0 };
     if (l1pte) {
 
     v_mapping mapping = { .flags = 0, .pa = 0, .pn = 0 };
     if (l1pte) {

-        x86_pte_t l2pte =
-          ((x86_page_table*)L2_VADDR(l1_index))->entry[l2_index];
+        x86_pte_t* l2pte =
+          &((x86_page_table*)L2_VADDR(l1_index))->entry[l2_index];

         if (l2pte) {
         if (l2pte) {

-            mapping.flags = PG_ENTRY_FLAGS(l2pte);
-            mapping.pa = PG_ENTRY_ADDR(l2pte);
+            mapping.flags = PG_ENTRY_FLAGS(*l2pte);
+            mapping.pa = PG_ENTRY_ADDR(*l2pte);

             mapping.pn = mapping.pa >> PG_SIZE_BITS;
             mapping.pn = mapping.pa >> PG_SIZE_BITS;

+            mapping.pte = l2pte;

         }
     }
 
         }
     }
 


@@ -240,4 +255,19 @@ void*
 vmm_v2p(void* va)
 {
     return (void*)vmm_lookup(va).pa;
 vmm_v2p(void* va)
 {
     return (void*)vmm_lookup(va).pa;

+}
+
+void*
+vmm_mount_pd(uintptr_t mnt, void* pde) {
+    x86_page_table* l1pt = (x86_page_table*)L1_BASE_VADDR;
+    l1pt->entry[(mnt >> 22)] = NEW_L1_ENTRY(T_SELF_REF_PERM, pde);
+    cpu_invplg(mnt);
+    return mnt;
+}
+
+void*
+vmm_unmount_pd(uintptr_t mnt) {
+    x86_page_table* l1pt = (x86_page_table*)L1_BASE_VADDR;
+    l1pt->entry[(mnt >> 22)] = 0;
+    cpu_invplg(mnt);

 }
\ No newline at end of file
 }
\ No newline at end of file