From: acevest <zhaoyanbai@126.com>
Date: Wed, 21 Aug 2024 07:47:56 +0000 (+0800)
Subject: 更改alloc_pages接口返回值
X-Git-Url: http://zhaoyanbai.com/repos/%22http:/www.isc.org/icons/zpipe.c?a=commitdiff_plain;h=7b01bd07632c4f2264440dc3d93fff3cdcac82eb;p=kernel.git

更改alloc_pages接口返回值
---

diff --git a/drivers/ide.c b/drivers/ide.c
index fa65c10..7985baa 100644
--- a/drivers/ide.c
+++ b/drivers/ide.c
@@ -70,7 +70,7 @@ void ide_pci_init(pci_device_t *pci) {
         ide_pci_controller[i].bus_cmd = iobase + PCI_IDE_CMD;
         ide_pci_controller[i].bus_status = iobase + PCI_IDE_STATUS;
         ide_pci_controller[i].bus_prdt = iobase + PCI_IDE_PRDT;
-        ide_pci_controller[i].prdt = (prdte_t *)alloc_one_page(0);
+        ide_pci_controller[i].prdt = (prdte_t *)page2va(alloc_one_page(0));
 
         ide_pci_controller[i].pci = pci;
     }
diff --git a/fs/buffer.c b/fs/buffer.c
index 823d38f..597eae6 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -213,7 +213,7 @@ void init_buffer() {
         page_t *page = NULL;
         for (int j = 0; j < MAX_BBUFFER_CNT; j++) {
             if (page_left_space < blocksize) {
-                data = (void *)(alloc_one_page(0));
+                data = (void *)page2va(alloc_one_page(0));
                 page = va2page(data);
             }
 
diff --git a/include/page.h b/include/page.h
index 30e2238..bbe407d 100644
--- a/include/page.h
+++ b/include/page.h
@@ -103,14 +103,14 @@ typedef unsigned long pte_t;
 #define PAGE_UP(page) (((unsigned long)page + PAGE_SIZE - 1) & PAGE_MASK)
 #define PAGE_DOWN PAGE_ALIGN
 
-#define PAGE_FLAGS(addr) ((addr)-PAGE_ALIGN(addr))
+#define PAGE_FLAGS(addr) ((addr) - PAGE_ALIGN(addr))
 
 #define va2pa(x) (((unsigned long)(x)) - PAGE_OFFSET)
 #define pa2va(x) ((void *)(((unsigned long)(x)) + PAGE_OFFSET))
 
 // pfn: page frame number
 #define pa2pfn(addr) ((addr) >> PAGE_SHIFT)
-#define pfn2pa(pfn) ((pfn) << PAGE_SHIFT)
+#define pfn2pa(pfn) ((void *)((pfn) << PAGE_SHIFT))
 
 #define va2pfn(addr) pa2pfn(va2pa(addr))
 #define pfn2va(pfn) pa2va(pfn2pa(pfn))
@@ -155,6 +155,7 @@ typedef struct page {
 } page_t;
 
 void *page2va(page_t *page);
+void *page2pa(page_t *page);
 page_t *_va2page(unsigned long addr);
 page_t *_pa2page(unsigned long addr);
 
@@ -181,7 +182,7 @@ typedef struct free_area {
     list_head_t free_list;
 } free_area_t;
 
-unsigned long alloc_pages(unsigned int gfp_mask, unsigned int order);
+page_t *alloc_pages(unsigned int gfp_mask, unsigned int order);
 void free_pages(unsigned long addr);
 
 #define alloc_one_page(gfp_mask) alloc_pages(gfp_mask, 0)
diff --git a/kernel/exec.c b/kernel/exec.c
index cac3df4..0a328c3 100644
--- a/kernel/exec.c
+++ b/kernel/exec.c
@@ -35,7 +35,7 @@ void put_paging(unsigned long vaddr, unsigned long paddr, unsigned long flags) {
     pte_t *page_table = (pte_t *)PAGE_ALIGN(page_dir[npde]);
 
     if (page_table == 0) {
-        page_table = (pte_t *)alloc_one_page(0);
+        page_table = (pte_t *)page2va(alloc_one_page(0));
         memset(page_table, 0, PAGE_SIZE);
         page_table = (pte_t *)va2pa(page_table);
         assert(page_table != 0);
@@ -56,7 +56,7 @@ int sysc_exec(const char *path, char *const argv[]) {
 
     ext2_read_inode(ino, &inode);
 
-    Elf32_Ehdr *ehdr = (Elf32_Ehdr *)alloc_one_page(0);
+    Elf32_Ehdr *ehdr = (Elf32_Ehdr *)(page2va(alloc_one_page(0)));
     assert(ehdr != 0);
     ext2_read_data(&inode, 0, PAGE_SIZE, (char *)ehdr);
     printk("%08x\n", *((unsigned long *)ehdr->e_ident));
@@ -68,8 +68,8 @@ int sysc_exec(const char *path, char *const argv[]) {
         Elf32_Phdr *phdr;
         phdr = (Elf32_Phdr *)(((unsigned long)ehdr) + ehdr->e_phoff + (i * ehdr->e_phentsize));
 
-        printk("Type %08x Off %08x Va %08x Pa %08x Fsz %08x Mmsz %08x\n", phdr->p_type, phdr->p_offset, phdr->p_vaddr, phdr->p_paddr, phdr->p_filesz,
-               phdr->p_memsz);
+        printk("Type %08x Off %08x Va %08x Pa %08x Fsz %08x Mmsz %08x\n", phdr->p_type, phdr->p_offset, phdr->p_vaddr,
+               phdr->p_paddr, phdr->p_filesz, phdr->p_memsz);
 
         unsigned long vaddr = phdr->p_vaddr;
         unsigned long offset = phdr->p_offset;
diff --git a/kernel/fork.c b/kernel/fork.c
index ab6d887..c4e1b46 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -39,7 +39,7 @@ int do_fork(pt_regs_t *regs, unsigned long flags) {
     list_add(&tsk->list, &all_tasks);
     irq_restore(iflags);
 
-    tsk->cr3 = va2pa((unsigned long)alloc_one_page(0));
+    tsk->cr3 = (uint32_t)page2pa(alloc_one_page(0));
     assert(tsk->cr3 != 0);
 
     unsigned int i, j;
@@ -67,7 +67,7 @@ int do_fork(pt_regs_t *regs, unsigned long flags) {
         // 这里不用再为每个PDE拷贝一次PageTable，只需要拷贝PageDirectory并将其低于768的写权限去掉
         // 同时需要修改缺页异常doPageFault的逻辑
         if (PAGE_ALIGN(spde) != 0) {
-            dpde = alloc_one_page(0);
+            dpde = page2va(alloc_one_page(0));
             assert(dpde != 0);
             memset((void *)dpde, 0, PAGE_SIZE);
             dpde = PAGE_FLAGS(spde) | (unsigned long)va2pa(dpde);
@@ -102,7 +102,7 @@ int do_fork(pt_regs_t *regs, unsigned long flags) {
         strcpy(tsk->name, (char *)(child_regs->eax));
         child_regs->eax = 0;
     } else {
-        child_regs->eip = *((unsigned long *)&&fork_child);
+        child_regs->eip = *((unsigned long *) && fork_child);
     }
 
     // 这一句已经不需要了，通过fork_child已经能给子进程返回0了
diff --git a/kernel/task_user.c b/kernel/task_user.c
index cb8b880..8356609 100644
--- a/kernel/task_user.c
+++ b/kernel/task_user.c
@@ -63,10 +63,10 @@ void user_task_entry() {
     current->priority = 7;
 
     unsigned long ring3_text_page = va2pa(ring3_entry);
-    unsigned long ring3_bss_page = va2pa(alloc_one_page(0));
+    unsigned long ring3_bss_page = (unsigned long)page2pa(alloc_one_page(0));
 
-    unsigned long *pt_text_page = (unsigned long *)(alloc_one_page(0));
-    unsigned long *pt_bss_page = (unsigned long *)(alloc_one_page(0));
+    unsigned long *pt_text_page = (unsigned long *)page2va(alloc_one_page(0));
+    unsigned long *pt_bss_page = (unsigned long *)page2va(alloc_one_page(0));
 
     unsigned long *p = (unsigned long *)(pa2va(current->cr3));
 
diff --git a/mm/buddy.c b/mm/buddy.c
index 15dd0ee..7463ebd 100644
--- a/mm/buddy.c
+++ b/mm/buddy.c
@@ -46,15 +46,16 @@ page_t *_pa2page(unsigned long paddr) {
 }
 
 void *page2va(page_t *page) { return pfn2va((page)-buddy_system.page_map); }
+void *page2pa(page_t *page) { return pfn2pa((page)-buddy_system.page_map); }
 
 page_t *__alloc_pages(unsigned int order) {
     //
     page_t *page = 0;
-    page_t *buddy = 0;
     free_area_t *area;
-    unsigned long size;
     unsigned int select_order;
     unsigned int i;
+
+    // 找到首个满足 >= order的page块
     for (select_order = order; select_order < MAX_ORDER; ++select_order) {
         area = buddy_system.free_area + select_order;
         if (!list_empty(&(area->free_list))) {
@@ -65,25 +66,28 @@ page_t *__alloc_pages(unsigned int order) {
     return 0;
 
 found:
+    // 从链表取下这个连续的page块
     page = list_entry(area->free_list.next, page_t, lru);
     list_del(&(page->lru));
     ClearPagePrivate(page);
     page->private = 0;
     area->free_count--;
 
+    // 二分这个page块，把空闲的挂到对应的order队列上
+    // 直到得到order大小的page块
     while (select_order > order) {
         area--;
         select_order--;
-        size = 1UL << select_order;
+        unsigned long buddy_offset = 1UL << select_order;
 
-        buddy = page + size;
-        list_add(&(buddy->lru), &(area->free_list));
+        page_t *buddy_page = page + buddy_offset;
+        list_add(&(buddy_page->lru), &(area->free_list));
         area->free_count++;
-        buddy->private = select_order;
-        SetPagePrivate(buddy);
+        buddy_page->private = select_order;
+        SetPagePrivate(buddy_page);
     }
 
-    //
+    // 初始化这一连续的page块
     for (i = 0; i < (1UL << order); ++i) {
         page_t *p = page + i;
         p->head_page = page;
@@ -95,7 +99,7 @@ found:
     return page;
 }
 
-unsigned long alloc_pages(unsigned int gfp_mask, unsigned int order) {
+page_t *alloc_pages(unsigned int gfp_mask, unsigned int order) {
     // gfp_mask
     // ...
 
@@ -104,8 +108,10 @@ unsigned long alloc_pages(unsigned int gfp_mask, unsigned int order) {
     page_t *page = __alloc_pages(order);
     irq_restore(flags);
 
-    unsigned long addr = (unsigned long)page2va(page);
-    return addr;
+    // unsigned long addr = (unsigned long)page2va(page);
+    // return addr;
+
+    return page;
 }
 
 void __free_pages(page_t *page, unsigned int order) {
@@ -190,8 +196,7 @@ void init_buddy_system() {
     buddy_system.page_map = alloc_from_bootmem(page_map_size, "buddy");
     if (0 == buddy_system.page_map) {
         printk("can not go on playing...\n");
-        while (1)
-            ;
+        while (1);
     }
 
     buddy_system.page_map_end = buddy_system.page_map + pfn_cnt + 1;
diff --git a/mm/mm.c b/mm/mm.c
index 71deb05..8fa0dce 100644
--- a/mm/mm.c
+++ b/mm/mm.c
@@ -50,7 +50,7 @@ void init_paging() {
     // 最大限制内存1G
     for (pfn = pa2pfn(BOOT_INIT_PAGETBL_CNT << 22); pfn < bootmem_data.max_pfn; ++pfn) {
         unsigned long ti = pfn % PAGE_PTE_CNT;
-        unsigned long page_addr = pfn2pa(pfn);
+        unsigned long page_addr = (unsigned long)pfn2pa(pfn);
         if (ti == 0) {
             pgtb_addr = (unsigned long *)alloc_from_bootmem(PAGE_SIZE, "paging");
             if (0 == pgtb_addr) {
diff --git a/mm/page.c b/mm/page.c
index 925580b..3b27a8d 100644
--- a/mm/page.c
+++ b/mm/page.c
@@ -21,14 +21,14 @@ void do_no_page(void *addr) {
     pde_t *page_dir = (pde_t *)pa2va(current->cr3);
     pte_t *page_tbl = 0;
 
-    unsigned long page = alloc_one_page(0);
+    unsigned long page = (unsigned long)page2va(alloc_one_page(0));
     assert(page != 0);
 
     int npde = get_npde(addr);
     int npte = get_npte(addr);
 
     if (page_dir[npde] == 0) {
-        page_tbl = (pte_t *)alloc_one_page(0);
+        page_tbl = (pte_t *)page2va(alloc_one_page(0));
         assert(page_tbl != 0);
 
         memset((void *)page_tbl, 0, PAGE_SIZE);
@@ -57,7 +57,7 @@ void do_wp_page(void *addr) {
     // 如果是因为PDE被写保护
     if (*pde & PDE_RW == 0) {
         // 1. 分配一个页表
-        unsigned long newtbl = alloc_one_page(0);
+        unsigned long newtbl = (unsigned long)page2va(alloc_one_page(0));
         assert(newtbl != 0);
 
         // 2. 拷贝页表
@@ -88,7 +88,7 @@ void do_wp_page(void *addr) {
     // 如果PTE的位置被写保护
     if (*pte & PTE_RW == 0) {
         // 1. 分配一个页表
-        unsigned long newaddr = alloc_one_page(0);
+        unsigned long newaddr = (unsigned long)page2va(alloc_one_page(0));
         assert(newaddr != 0);
 
         // 2. 拷贝页表
@@ -113,7 +113,7 @@ void do_wp_page(void *addr) {
         page->count--;
         unsigned long flags = PAGE_FLAGS(page_tbl[npte]);
         unsigned long wp_va_addr = (unsigned long)pa2va(wp_pa_addr);
-        unsigned long newtbl = alloc_one_page(0);
+        unsigned long newtbl = (unsigned long) page2va(alloc_one_page(0));
         assert(newtbl != 0);
 
         memcpy((void *)newtbl, (void *)wp_va_addr, PAGE_SIZE);
diff --git a/mm/slub.c b/mm/slub.c
index d700130..92e48e8 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -28,21 +28,14 @@ page_t *get_partial(kmem_cache_t *cache, gfp_t gfpflags) {
 
 // 从伙伴系统批发页，并将之初始化成一个链表
 page_t *new_slub(kmem_cache_t *cache, gfp_t gfpflags) {
-    // alloc pages from buddy system
-    unsigned long bgn = alloc_pages(gfpflags, cache->order);
-    unsigned long end = 0;
-
-    // 找到该页的管理结构
-    page_t *page = va2page(bgn);
-
-    //
+    page_t *page = alloc_pages(gfpflags, cache->order);
     if (0 == page) {
         return 0;
     }
 
-    end = bgn + cache->objects * cache->size;
+    unsigned long bgn = (unsigned long)page2va(page);
+    unsigned long end = bgn + cache->objects * cache->size;
 
-#if 1
     unsigned long last = bgn;
     unsigned long addr;
 
@@ -55,15 +48,6 @@ page_t *new_slub(kmem_cache_t *cache, gfp_t gfpflags) {
 
     // 最后一个赋值为0
     *((void **)last) = 0;
-#else
-    unsigned long addr;
-    for (addr = bgn; addr < end; addr += cache->size) {
-        *(unsigned long *)addr = addr + cache->size;
-    }
-
-    addr = end - cache->size;
-    *(unsigned long *)addr = 0;
-#endif
 
     page->freelist = (void **)bgn;
     page->inuse = 0;