X-Git-Url: https://scm.lunaixsky.com/lunaix-os.git/blobdiff_plain/e141fd4dcd5effc2dbe59a498d7ea274b7199147..2803826a2373620dbfce8a5bff1e6a01dd594953:/lunaix-os/kernel/mm/vmm.c diff --git a/lunaix-os/kernel/mm/vmm.c b/lunaix-os/kernel/mm/vmm.c index 364332e..fe3d65c 100644 --- a/lunaix-os/kernel/mm/vmm.c +++ b/lunaix-os/kernel/mm/vmm.c @@ -1,143 +1,146 @@ -#include -#include +#include +#include #include -#include - -// TODO: Move these nasty inline asm stuff into hal -// These should be arch dependent -ptd_t* get_pd() { - ptd_t* pd; - #ifdef __ARCH_IA32 - __asm__( - "movl %%cr3, %0\n" - "andl $0xfffff000, %0" - : "=r"(pd) - ); - #endif - return P2V(pd); -} - -void set_pd(ptd_t* pd) { - #ifdef __ARCH_IA32 - __asm__( - "movl %0, %%eax\n" - "andl $0xfffff000, %%eax\n" - "movl %%eax, %%cr3\n" - : - : "r" (pd) - ); - #endif -} +#include +#include -void vmm_init() { - // TODO: something here? +void +vmm_init() +{ + // XXX: something here? } -ptd_t* vmm_init_pd() { - ptd_t* dir = pmm_alloc_page(); - for (size_t i = 0; i < 1024; i++) - { - dir[i] = 0; +x86_page_table* +vmm_init_pd() +{ + x86_page_table* dir = + (x86_page_table*)pmm_alloc_page(KERNEL_PID, PP_FGPERSIST); + for (size_t i = 0; i < PG_MAX_ENTRIES; i++) { + dir->entry[i] = PTE_NULL; } - - // 自己映射自己，方便我们在软件层面进行查表地址转换 - dir[1023] = PDE(T_SELF_REF_PERM, dir); + + // 递归映射，方便我们在软件层面进行查表地址转换 + dir->entry[PG_MAX_ENTRIES - 1] = NEW_L1_ENTRY(T_SELF_REF_PERM, dir); return dir; } -void* vmm_map_page(void* va, void* pa, pt_attr dattr, pt_attr tattr) { - // 显然，对空指针进行映射没有意义。 - if (!pa || !va) { - return NULL; - } - - uintptr_t pd_offset = PD_INDEX(va); - uintptr_t pt_offset = PT_INDEX(va); - ptd_t* ptd = (ptd_t*)PTD_BASE_VADDR; - - // 在页表与页目录中找到一个可用的空位进行映射（位于va或其附近） - ptd_t* pde = ptd[pd_offset]; - pt_t* pt = (uintptr_t)PT_VADDR(pd_offset); - while (pde && pd_offset < 1024) { - if (pt_offset == 1024) { - pd_offset++; - pt_offset = 0; - pde = ptd[pd_offset]; - pt = (pt_t*)PT_VADDR(pd_offset); +int +vmm_set_mapping(uintptr_t mnt, + uintptr_t va, + uintptr_t pa, + pt_attr attr, + int options) +{ + assert((uintptr_t)va % PG_SIZE == 0); + + uintptr_t l1_inx = L1_INDEX(va); + uintptr_t l2_inx = L2_INDEX(va); + x86_page_table* l1pt = (x86_page_table*)(mnt | (1023 << 12)); + x86_page_table* l2pt = (x86_page_table*)(mnt | (l1_inx << 12)); + + // See if attr make sense + assert(attr <= 128); + + if (!l1pt->entry[l1_inx]) { + x86_page_table* new_l1pt_pa = pmm_alloc_page(KERNEL_PID, PP_FGPERSIST); + + // 物理内存已满！ + if (!new_l1pt_pa) { + return 0; } - // 页表有空位，只需要开辟一个新的 PTE - if (pt && !pt[pt_offset]) { - pt[pt_offset] = PTE(tattr, pa); - return V_ADDR(pd_offset, pt_offset, PG_OFFSET(va)); + + // This must be writable + l1pt->entry[l1_inx] = + NEW_L1_ENTRY(attr | PG_WRITE | PG_PRESENT, new_l1pt_pa); + + memset((void*)l2pt, 0, PG_SIZE); + } else { + x86_pte_t pte = l2pt->entry[l2_inx]; + if (pte && (options & VMAP_IGNORE)) { + return 1; } - pt_offset++; } - - // 页目录与所有页表已满！ - if (pd_offset > 1024) { - return NULL; + + if (mnt == PD_REFERENCED) { + cpu_invplg(va); } - // 页目录有空位，需要开辟一个新的 PDE - uint8_t* new_pt_pa = pmm_alloc_page(); - - // 物理内存已满！ - if (!new_pt_pa) { - return NULL; + if ((options & VMAP_NOMAP)) { + return 1; } - - ptd[pd_offset] = PDE(dattr, new_pt_pa); - - memset((void*)PT_VADDR(pd_offset), 0, PM_PAGE_SIZE); - pt[pt_offset] = PTE(tattr, pa); - return V_ADDR(pd_offset, pt_offset, PG_OFFSET(va)); + l2pt->entry[l2_inx] = NEW_L2_ENTRY(attr, pa); + return 1; } -void* vmm_alloc_page(void* vpn, pt_attr dattr, pt_attr tattr) { - void* pp = pmm_alloc_page(); - void* result = vmm_map_page(vpn, pp, dattr, tattr); - if (!result) { - pmm_free_page(pp); +uintptr_t +vmm_del_mapping(uintptr_t mnt, uintptr_t va) +{ + assert(((uintptr_t)va & 0xFFFU) == 0); + + uint32_t l1_index = L1_INDEX(va); + uint32_t l2_index = L2_INDEX(va); + + // prevent unmap of recursive mapping region + if (l1_index == 1023) { + return 0; } - return result; -} -void vmm_unmap_page(void* vpn) { - uintptr_t pd_offset = PD_INDEX(vpn); - uintptr_t pt_offset = PT_INDEX(vpn); - ptd_t* self_pde = PTD_BASE_VADDR; - - ptd_t pde = self_pde[pd_offset]; - - if (pde) { - pt_t* pt = (pt_t*)PT_VADDR(pd_offset); - uint32_t pte = pt[pt_offset]; - if (IS_CACHED(pte) && pmm_free_page(pte)) { - // 刷新TLB - #ifdef __ARCH_IA32 - __asm__("invlpg (%0)" :: "r"((uintptr_t)vpn) : "memory"); - #endif - } - pt[pt_offset] = 0; + x86_page_table* l1pt = (x86_page_table*)(mnt | (1023 << 12)); + + x86_pte_t l1pte = l1pt->entry[l1_index]; + + if (l1pte) { + x86_page_table* l2pt = (x86_page_table*)(mnt | (l1_index << 12)); + x86_pte_t l2pte = l2pt->entry[l2_index]; + + cpu_invplg(va); + l2pt->entry[l2_index] = PTE_NULL; + + return PG_ENTRY_ADDR(l2pte); } + + return 0; } -void* vmm_v2p(void* va) { - uintptr_t pd_offset = PD_INDEX(va); - uintptr_t pt_offset = PT_INDEX(va); - uintptr_t po = PG_OFFSET(va); - ptd_t* self_pde = PTD_BASE_VADDR; - - ptd_t pde = self_pde[pd_offset]; - if (pde) { - pt_t pte = ((pt_t*)PT_VADDR(pd_offset))[pt_offset]; - if (pte) { - uintptr_t ppn = pte >> 12; - return (void*)P_ADDR(ppn, po); +int +vmm_lookup(uintptr_t va, v_mapping* mapping) +{ + uint32_t l1_index = L1_INDEX(va); + uint32_t l2_index = L2_INDEX(va); + + x86_page_table* l1pt = (x86_page_table*)L1_BASE_VADDR; + x86_pte_t l1pte = l1pt->entry[l1_index]; + + if (l1pte) { + x86_pte_t* l2pte = + &((x86_page_table*)L2_VADDR(l1_index))->entry[l2_index]; + if (l2pte) { + mapping->flags = PG_ENTRY_FLAGS(*l2pte); + mapping->pa = PG_ENTRY_ADDR(*l2pte); + mapping->pn = mapping->pa >> PG_SIZE_BITS; + mapping->pte = l2pte; + mapping->va = va; + return 1; } } + return 0; +} + +void* +vmm_mount_pd(uintptr_t mnt, void* pde) +{ + x86_page_table* l1pt = (x86_page_table*)L1_BASE_VADDR; + l1pt->entry[(mnt >> 22)] = NEW_L1_ENTRY(T_SELF_REF_PERM, pde); + cpu_invplg(mnt); + return mnt; +} - return NULL; +void* +vmm_unmount_pd(uintptr_t mnt) +{ + x86_page_table* l1pt = (x86_page_table*)L1_BASE_VADDR; + l1pt->entry[(mnt >> 22)] = 0; + cpu_invplg(mnt); } \ No newline at end of file