A Total Overhaul on the Lunaix's Virtual Memory Model (#26)

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

diff --git a/lunaix-os/kernel/mm/dmm.c b/lunaix-os/kernel/mm/dmm.c
index cb87202e82c33c18a373dcffb5f7def06bbca515..f665e9d023863dbe0c709873edfe52c27a04683c 100644 (file)
--- a/lunaix-os/kernel/mm/dmm.c
+++ b/lunaix-os/kernel/mm/dmm.c
@@ -1,102 +1,62 @@
-/**
- * @file dmm.c
- * @author Lunaixsky
- * @brief Dynamic memory manager for heap. This design do not incorporate any\
- * specific implementation of malloc family. The main purpose of this routines
- * is to provide handy method to initialize & grow the heap as needed by
- * upstream implementation.
- *
- * This is designed to be portable, so it can serve as syscalls to malloc/free
- * in the c std lib.
- *
- * @version 0.2
- * @date 2022-03-3
- *
- * @copyright Copyright (c) Lunaixsky 2022
- *
- */
-
-#include <lunaix/mm/dmm.h>
-#include <lunaix/mm/page.h>
+#include <lunaix/mm/mmap.h>
 #include <lunaix/mm/vmm.h>
+#include <lunaix/process.h>
 #include <lunaix/status.h>
 
 #include <lunaix/spike.h>
 #include <lunaix/syscall.h>
+#include <lunaix/syscall_utils.h>
 
-extern void __kernel_heap_start;
-
-__DEFINE_LXSYSCALL1(int, sbrk, size_t, size)
-{
-    heap_context_t* uheap = &__current->mm.u_heap;
-    mutex_lock(&uheap->lock);
-    void* r = lxsbrk(uheap, size, PG_ALLOW_USER);
-    mutex_unlock(&uheap->lock);
-    return r;
-}
-
-__DEFINE_LXSYSCALL1(void*, brk, void*, addr)
+void
+__heap_copied(struct mm_region* region)
 {
-    heap_context_t* uheap = &__current->mm.u_heap;
-    mutex_lock(&uheap->lock);
-    int r = lxbrk(uheap, addr, PG_ALLOW_USER);
-    mutex_unlock(&uheap->lock);
-    return r;
+    mm_index((void**)&region->proc_vms->heap, region);
 }
 
 int
-dmm_init(heap_context_t* heap)
+create_heap(struct proc_mm* pvms, ptr_t addr)
 {
-    assert((uintptr_t)heap->start % BOUNDARY == 0);
-
-    heap->brk = heap->start;
-    mutex_init(&heap->lock);
-
-    int perm = PG_ALLOW_USER;
-    if (heap->brk >= &__kernel_heap_start) {
-        perm = 0;
+    struct mmap_param map_param = { .pvms = pvms,
+                                    .vms_mnt = VMS_SELF,
+                                    .flags = MAP_ANON | MAP_PRIVATE,
+                                    .type = REGION_TYPE_HEAP,
+                                    .proct = PROT_READ | PROT_WRITE,
+                                    .mlen = PAGE_SIZE };
+    int status = 0;
+    struct mm_region* heap;
+    if ((status = mmap_user(NULL, &heap, addr, NULL, &map_param))) {
+        return status;
     }
 
-    return vmm_set_mapping(PD_REFERENCED, heap->brk, 0, PG_WRITE | perm) !=
-           NULL;
-}
+    heap->region_copied = __heap_copied;
+    mm_index((void**)&pvms->heap, heap);
 
-int
-lxbrk(heap_context_t* heap, void* addr, int user)
-{
-    return -(lxsbrk(heap, addr - heap->brk, user) == (void*)-1);
+    return status;
 }
 
-void*
-lxsbrk(heap_context_t* heap, size_t size, int user)
+__DEFINE_LXSYSCALL1(void*, sbrk, ssize_t, incr)
 {
-    if (size == 0) {
-        return heap->brk;
-    }
-
-    void* current_brk = heap->brk;
+    struct proc_mm* pvms = vmspace(__current);
+    struct mm_region* heap = pvms->heap;
 
-    // The upper bound of our next brk of heap given the size.
-    // This will be used to calculate the page we need to allocate.
-    void* next = current_brk + ROUNDUP(size, BOUNDARY);
-
-    // any invalid situations
-    if (next >= heap->max_addr || next < current_brk) {
-        __current->k_status = LXINVLDPTR;
-        return (void*)-1;
+    assert(heap);
+    int err = mem_adjust_inplace(&pvms->regions, heap, heap->end + incr);
+    if (err) {
+        return (void*)DO_STATUS(err);
     }
+    return (void*)heap->end;
+}
+
+__DEFINE_LXSYSCALL1(int, brk, void*, addr)
+{
+    struct proc_mm* pvms = vmspace(__current);
+    struct mm_region* heap = pvms->heap;
 
-    uintptr_t diff = PG_ALIGN(next) - PG_ALIGN(current_brk);
-    if (diff) {
-        // if next do require new pages to be mapped
-        for (size_t i = 0; i < diff; i += PG_SIZE) {
-            vmm_set_mapping(PD_REFERENCED,
-                            PG_ALIGN(current_brk) + PG_SIZE + i,
-                            0,
-                            PG_WRITE | user);
-        }
+    if (!heap) {
+        return DO_STATUS(create_heap(pvms, (ptr_t)addr));
     }
 
-    heap->brk += size;
-    return current_brk;
+    assert(heap);
+    int err = mem_adjust_inplace(&pvms->regions, heap, (ptr_t)addr);
+    return DO_STATUS(err);
 }
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