DragonOS-Community/DragonOS
4
1
Fork 0
mirror of https://github.com/DragonOS-Community/DragonOS.git synced 2025-06-20 10:06:31 +00:00
Code Issues Releases Wiki Activity

new: 映射vma

Browse Source
This commit is contained in:
fslongjin
2022-08-11 22:15:53 +08:00
parent 8d39334e39
commit 51bc465a25
9 changed files with 326 additions and 88 deletions
Download Patch File Download Diff File Expand all files Collapse all files

104
kernel/mm/mmap.c
View File

@ -1,5 +1,6 @@
#include "mm.h"
#include "slab.h"
#include "internal.h"
#include <common/compiler.h>
extern uint64_t mm_total_2M_pages;
@ -72,10 +73,16 @@ int mm_map_proc_page_table(ul proc_page_table_addr, bool is_phys, ul virt_addr_s
// 计算线性地址对应的pml4页表项的地址
mm_pgt_entry_num_t pgt_num;
mm_calculate_entry_num(length, &pgt_num);
// kdebug("ent1=%d ent2=%d ent3=%d, ent4=%d", pgt_num.num_PML4E, pgt_num.num_PDPTE, pgt_num.num_PDE, pgt_num.num_PTE);
// 已映射的内存大小
uint64_t length_mapped = 0;
// 对user标志位进行校正
if (flags & PAGE_U_S)
user = true;
else
user = false;
uint64_t pml4e_id = ((virt_addr_start >> PAGE_GDT_SHIFT) & 0x1ff);
uint64_t *pml4_ptr;
if (is_phys)
@ -192,7 +199,6 @@ failed:;
return -EFAULT;
}
/**
* @brief 从页表中清除虚拟地址的映射
*
@ -262,7 +268,7 @@ void mm_unmap_proc_table(ul proc_page_table_addr, bool is_phys, ul virt_addr_sta
ul *pde_ptr = pd_ptr + pde_id;
// 存在4级页表
if (unlikely(((*pde_ptr) & (1 << 7)) == 0))
if (((*pde_ptr) & (1 << 7)) == 0)
{
// 存在4K页
uint64_t pte_id = (((virt_addr_start + length_unmapped) >> PAGE_4K_SHIFT) & 0x1ff);
@ -291,7 +297,7 @@ void mm_unmap_proc_table(ul proc_page_table_addr, bool is_phys, ul virt_addr_sta
// 3级页表已经空了，释放页表
if (unlikely(mm_check_page_table(pd_ptr)) == 0)
kfree(pd_ptr);
kfree(pd_ptr);
}
// 2级页表已经空了，释放页表
if (unlikely(mm_check_page_table(pdpt_ptr)) == 0)
@ -299,3 +305,93 @@ void mm_unmap_proc_table(ul proc_page_table_addr, bool is_phys, ul virt_addr_sta
}
flush_tlb();
}
/**
* @brief 创建VMA，并将物理地址映射到指定的虚拟地址处
*
* @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
* @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 retval = 0;
struct vm_area_struct *vma = vm_area_alloc(mm);
if (unlikely(vma == NULL))
return -ENOMEM;
vma->vm_ops = vm_ops;
vma->vm_flags = vm_flags;
vma->vm_start = vaddr;
vma->vm_end = vaddr + length;
// 将VMA加入链表
__vma_link_list(mm, vma, mm->vmas);
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
*/
// 先映射2M页
if (likely(len_2m > 0))
{
uint64_t page_flags = 0;
if (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);
if (unlikely(retval != 0))
goto failed;
}
if (likely(len_4k > 0))
{
len_4k = ALIGN(len_4k, PAGE_4K_SIZE);
uint64_t page_flags = 0;
if (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);
if (unlikely(retval != 0))
goto failed;
}
flush_tlb();
return 0;
failed:;
__vma_unlink_list(mm, vma);
vm_area_free(vma);
return retval;
}
/**
* @brief 在页表中取消指定的vma的映射
*
* @param mm 指定的mm
* @param vma 待取消映射的vma
* @param paddr 返回的被取消映射的起始物理地址
* @return int 返回码
*/
int mm_umap_vma(struct mm_struct *mm, struct vm_area_struct *vma, uint64_t *paddr)
{
// 确保vma对应的mm与指定的mm相一致
if (unlikely(vma->vm_mm != mm))
return -EINVAL;
if (paddr != NULL)
*paddr = __mm_get_paddr(mm, vma->vm_start);
mm_unmap_proc_table((uint64_t)mm->pgd, true, vma->vm_start, vma->vm_end - vma->vm_start);
return 0;
}