🆕 内核线程（在kernel_thtread函数中调用test_mm会产生问题）

2025-06-18 08:06:32 +00:00 · 2022-02-10 13:45:38 +08:00
parent 39ddc21ca5
commit 67633eb04e
12 changed files with 752 additions and 83 deletions
--- a/kernel/mm/mm.c
+++ b/kernel/mm/mm.c
@ -159,7 +159,7 @@ void mm_init()
    {
        struct Zone *z = memory_management_struct.zones_struct + i;
        //printk_color(ORANGE, BLACK, "zone_addr_start:%#18lx, zone_addr_end:%#18lx, zone_length:%#18lx, pages_group:%#18lx, count_pages:%#18lx\n",
-         //            z->zone_addr_start, z->zone_addr_end, z->zone_length, z->pages_group, z->count_pages);
+        //            z->zone_addr_start, z->zone_addr_end, z->zone_length, z->pages_group, z->count_pages);

        // 1GB以上的内存空间不做映射
        if (z->zone_addr_start == 0x100000000)
@ -180,7 +180,7 @@ void mm_init()
        page_init(memory_management_struct.pages_struct + j, PAGE_PGT_MAPPED | PAGE_KERNEL | PAGE_KERNEL_INIT | PAGE_ACTIVE);
    }

-    ul *cr3 = get_CR3();
+    global_CR3 = get_CR3();

    /*
    printk_color(INDIGO, BLACK, "cr3:\t%#018lx\n", cr3);
@ -188,9 +188,11 @@ void mm_init()
    printk_color(INDIGO, BLACK, "**cr3:\t%#018lx\n", *phys_2_virt(*(phys_2_virt(cr3)) & (~0xff)) & (~0xff));
    */

+   /*
    // 消除一致性页表映射，将页目录（PML4E）的前10项清空
    for (int i = 0; i < 10; ++i)
-        *(phys_2_virt(cr3) + i) = 0UL;
+        *(phys_2_virt(global_CR3) + i) = 0UL;
+        */

    flush_tlb();

@ -241,7 +243,7 @@ unsigned long page_init(struct Page *page, ul flags)
 /**
 * @brief 从已初始化的页结构中搜索符合申请条件的、连续num个struct page
 * 
- * @param zone_select 选择内存区域, 可选项：dma, mapped in pgt, unmapped in pgt
+ * @param zone_select 选择内存区域, 可选项：dma, mapped in pgt(normal), unmapped in pgt
 * @param num 需要申请的连续内存页的数量 num<=64
 * @param flags 将页面属性设置成flag
 * @return struct Page* 
@ -310,4 +312,36 @@ struct Page *alloc_pages(unsigned int zone_select, int num, ul flags)
            }
        }
    }
+    return NULL;
+}
+
+unsigned long page_clean(struct Page *p)
+{
+    if (!p->attr)
+        p->attr = 0;
+    else if ((p->attr & PAGE_REFERENCED) || (p->attr & PAGE_K_SHARE_TO_U))
+    {
+        // 被引用的页或内核共享给用户态的页
+        --p->ref_counts;
+        --p->zone->total_pages_link;
+
+        // 当引用为0时
+        if (!p->ref_counts)
+        {
+            p->attr = 0;
+            --p->zone->count_pages_using;
+            ++p->zone->count_pages_free;
+        }
+    }
+    else
+    {
+        // 将bmp复位
+        *(memory_management_struct.bmp + ((p->addr_phys >> PAGE_2M_SHIFT) >> 6)) &= ~(1UL << ((p->addr_phys >> PAGE_2M_SHIFT) % 64));
+
+        p->attr = 0;
+        p->ref_counts = 0;
+        --p->zone->count_pages_using;
+        ++p->zone->count_pages_free;
+        --p->zone->total_pages_link;
+    }
 }
--- a/kernel/mm/mm.h
+++ b/kernel/mm/mm.h
@ -7,7 +7,7 @@
 #define PTRS_PER_PGT 512

 // 内核层的起始地址
-#define KERNEL_BASE_ADDR 0xffff800000000000
+#define KERNEL_BASE_ADDR ((unsigned long)0xffff800000000000)

 #define PAGE_4K_SHIFT 12
 #define PAGE_2M_SHIFT 21
@ -29,14 +29,18 @@
 // 虚拟地址与物理地址转换
 #define virt_2_phys(addr) ((unsigned long)(addr)-KERNEL_BASE_ADDR)
 #define phys_2_virt(addr) ((unsigned long *)((unsigned long)(addr) + KERNEL_BASE_ADDR))
+#define Phy_To_Virt(addr) ((unsigned long *)((unsigned long)(addr) + KERNEL_BASE_ADDR))
+
+#define Virt_To_2M_Page(kaddr) (memory_management_struct.pages_struct + (virt_2_phys(kaddr) >> PAGE_2M_SHIFT))
+#define Phy_to_2M_Page(kaddr) (memory_management_struct.pages_struct + ((unsigned long)(kaddr) >> PAGE_2M_SHIFT))

 // ===== 内存区域属性 =====
 // DMA区域
-#define ZONE_DMA (1<<0)
+#define ZONE_DMA (1 << 0)
 // 已在页表中映射的区域
-#define ZONE_NORMAL (1<<1)
+#define ZONE_NORMAL (1 << 1)
 // 未在页表中映射的区域
-#define ZONE_UNMAPPED_IN_PGT (1<<2)
+#define ZONE_UNMAPPED_IN_PGT (1 << 2)

 // ===== 页面属性 =====
 // 页面在页表中已被映射
@ -60,23 +64,21 @@
 // slab内存分配器的页
 #define PAGE_SLAB (1 << 9)

-
 /**
 * @brief 刷新TLB的宏定义
 * 由于任何写入cr3的操作都会刷新TLB，因此这个宏定义可以刷新TLB
 */
-#define flush_tlb()                \
-    do                             \
-    {                              \
-        ul tmp;                    \
-        __asm__ __volatile__(      \
-            "movq %%cr3, %0\n\t"   \
-            "movq %0, %%cr3\n\t"   \
+#define flush_tlb()                 \
+    do                              \
+    {                               \
+        ul tmp;                     \
+        __asm__ __volatile__(       \
+            "movq %%cr3, %0\n\t"    \
+            "movq %0, %%cr3\n\t"    \
            : "=r"(tmp)::"memory"); \
-                                   \
+                                    \
    } while (0);

-
 // Address Range Descriptor Structure 地址范围描述符
 struct ARDS
 {
@ -155,32 +157,39 @@ extern struct memory_desc memory_management_struct;
 // 导出内核程序的几个段的起止地址
 extern char _text;
 extern char _etext;
+extern char _data;
 extern char _edata;
+extern char _rodata;
+extern char _erodata;
+extern char _bss;
+extern char _ebss;
 extern char _end;

 // 每个区域的索引

 int ZONE_DMA_INDEX = 0;
-int ZONE_NORMAL_INDEX = 0;  //low 1GB RAM ,was mapped in pagetable
-int ZONE_UNMAPED_INDEX = 0; //above 1GB RAM,unmapped in pagetable
+int ZONE_NORMAL_INDEX = 0;  // low 1GB RAM ,was mapped in pagetable
+int ZONE_UNMAPED_INDEX = 0; // above 1GB RAM,unmapped in pagetable
+
+ul *global_CR3 = NULL;

 // 初始化内存管理单元
 void mm_init();

 /**
 * @brief 初始化内存页
- * 
+ *
 * @param page 内存页结构体
 * @param flags 标志位
 * 对于新页面： 初始化struct page
 * 对于当前页面属性/flags中含有引用属性或共享属性时，则只增加struct page和struct zone的被引用计数。否则就只是添加页表属性，并置位bmp的相应位。
- * @return unsigned long 
+ * @return unsigned long
 */
 unsigned long page_init(struct Page *page, ul flags);

 /**
 * @brief 读取CR3寄存器的值（存储了页目录的基地址）
- * 
+ *
 * @return unsigned*  cr3的值的指针
 */
 unsigned long *get_CR3()
@ -194,10 +203,27 @@ unsigned long *get_CR3()

 /**
 * @brief 从已初始化的页结构中搜索符合申请条件的、连续num个struct page
- * 
- * @param zone_select 选择内存区域, 可选项：dma, mapped in pgt, unmapped in pgt
+ *
+ * @param zone_select 选择内存区域, 可选项：dma, mapped in pgt(normal), unmapped in pgt
 * @param num 需要申请的内存页的数量 num<=64
 * @param flags 将页面属性设置成flag
- * @return struct Page* 
+ * @return struct Page*
 */
-struct Page* alloc_pages(unsigned int zone_select, int num, ul flags);
+struct Page *alloc_pages(unsigned int zone_select, int num, ul flags);
+
+/**
+ * @brief 释放内存页
+ *
+ * @param page 内存页结构体
+ * @return unsigned long
+ */
+unsigned long page_clean(struct Page *page);
+
+/**
+ * @brief 内存页表结构体
+ *
+ */
+typedef struct
+{
+    unsigned long pml4t;
+} pml4t_t;