DragonOS-Community/DragonOS
4
1
Fork 0
mirror of https://github.com/DragonOS-Community/DragonOS.git synced 2025-06-18 20:36:31 +00:00
Code Issues Releases Wiki Activity

new: vma反向映射

Browse Source
This commit is contained in:
fslongjin
2022-08-15 01:42:34 +08:00
parent f3cd2b7777
commit 1dd9195d69
20 changed files with 486 additions and 245 deletions
Download Patch File Download Diff File Expand all files Collapse all files

57
kernel/mm/mmap.c
View File

@ -306,17 +306,17 @@ void mm_unmap_proc_table(ul proc_page_table_addr, bool is_phys, ul virt_addr_sta
}
/**
* @brief 创建VMA，并将物理地址映射到指定的虚拟地址处
* @brief 创建VMA
*
* @param mm 要绑定的内存空间分布结构体
* @param vaddr 起始虚拟地址
* @param length 长度（字节）
* @param paddr 起始物理地址
* @param vm_flags vma的标志
* @param vm_ops vma的操作接口
* @param res_vma 返回的vma指针
* @return int 错误码
*/
int mm_map_vma(struct mm_struct *mm, uint64_t vaddr, uint64_t length, uint64_t paddr, vm_flags_t vm_flags, struct vm_operations_t *vm_ops)
int mm_create_vma(struct mm_struct *mm, uint64_t vaddr, uint64_t length, vm_flags_t vm_flags, struct vm_operations_t *vm_ops, struct vm_area_struct **res_vma)
{
int retval = 0;
struct vm_area_struct *vma = vm_area_alloc(mm);
@ -327,19 +327,50 @@ int mm_map_vma(struct mm_struct *mm, uint64_t vaddr, uint64_t length, uint64_t p
vma->vm_start = vaddr;
vma->vm_end = vaddr + length;
// 将vma与对应的anon_vma进行绑定
struct Page * pg = Phy_to_2M_Page(paddr);
// 将VMA加入链表
// 将VMA加入mm的链表
retval = vma_insert(mm, vma);
if (retval == -EEXIST) // 之前已经存在了相同的vma，直接返回
{
*res_vma = vma_find(mm, vma->vm_start);
kfree(vma);
return -EEXIST;
}
*res_vma = vma;
return 0;
}
/**
* @brief 将指定的物理地址映射到指定的vma处
*
* @param vma 要进行映射的VMA结构体
* @param paddr 起始物理地址
* @return int 错误码
*/
int mm_map_vma(struct vm_area_struct *vma, uint64_t paddr)
{
int retval = 0;
// 获取物理地址对应的页面
struct Page *pg = Phy_to_2M_Page(paddr);
if (unlikely(pg->anon_vma == NULL)) // 若页面不存在anon_vma，则为页面创建anon_vma
{
uint64_t rflags;
// todo: 查明为什么在mm_init中，spin init之后，pg会变为0
spin_init(&pg->op_lock);
spin_lock_irqsave(&pg->op_lock, rflags);
if (unlikely(pg->anon_vma == NULL))
__anon_vma_create_alloc(pg, false);
spin_unlock_irqrestore(&pg->op_lock, rflags);
}
barrier();
// 将anon vma与vma进行绑定
__anon_vma_add(pg->anon_vma, vma);
barrier();
uint64_t length = vma->vm_end - vma->vm_start;
// ==== 将地址映射到页表 ====
uint64_t len_4k = length % PAGE_2M_SIZE;
uint64_t len_2m = length - len_4k;
// ==== 将地址映射到页表
/*
todo: 限制页面的读写权限
*/
@ -348,12 +379,12 @@ int mm_map_vma(struct mm_struct *mm, uint64_t vaddr, uint64_t length, uint64_t p
if (likely(len_2m > 0))
{
uint64_t page_flags = 0;
if (vm_flags & VM_USER)
if (vma->vm_flags & VM_USER)
page_flags = PAGE_USER_PAGE;
else
page_flags = PAGE_KERNEL_PAGE;
// 这里直接设置user标志位为false，因为该函数内部会对其进行自动校正
retval = mm_map_proc_page_table((uint64_t)mm->pgd, true, vaddr, paddr, len_2m, page_flags, false, false, false);
retval = mm_map_proc_page_table((uint64_t)vma->vm_mm->pgd, true, vma->vm_start, paddr, len_2m, page_flags, false, false, false);
if (unlikely(retval != 0))
goto failed;
}
@ -363,12 +394,12 @@ int mm_map_vma(struct mm_struct *mm, uint64_t vaddr, uint64_t length, uint64_t p
len_4k = ALIGN(len_4k, PAGE_4K_SIZE);
uint64_t page_flags = 0;
if (vm_flags & VM_USER)
if (vma->vm_flags & VM_USER)
page_flags = PAGE_USER_4K_PAGE;
else
page_flags = PAGE_KERNEL_4K_PAGE;
// 这里直接设置user标志位为false，因为该函数内部会对其进行自动校正
retval = mm_map_proc_page_table((uint64_t)mm->pgd, true, vaddr + len_2m, paddr + len_2m, len_4k, page_flags, false, false, true);
retval = mm_map_proc_page_table((uint64_t)vma->vm_mm->pgd, true, vma->vm_start + len_2m, paddr + len_2m, len_4k, page_flags, false, false, true);
if (unlikely(retval != 0))
goto failed;
}
@ -376,9 +407,7 @@ int mm_map_vma(struct mm_struct *mm, uint64_t vaddr, uint64_t length, uint64_t p
flush_tlb();
return 0;
failed:;
kdebug("failed.");
__vma_unlink_list(mm, vma);
vm_area_free(vma);
kdebug("map VMA failed.");
return retval;
}