X-Git-Url: https://scm.lunaixsky.com/lunaix-os.git/blobdiff_plain/0067bc210e621ccda286092d081a7890d65e1c18..d251b620d312e819923e55e223e0eb43b72a3bc6:/lunaix-os/kernel/process.c diff --git a/lunaix-os/kernel/process.c b/lunaix-os/kernel/process.c index 29cff62..c4e348f 100644 --- a/lunaix-os/kernel/process.c +++ b/lunaix-os/kernel/process.c @@ -1,136 +1,239 @@ -#include -#include -#include +#include #include -#include #include -#include +#include +#include +#include +#include #include +#include +#include +#include LOG_MODULE("PROC") -void* __dup_pagetable(pid_t pid, uintptr_t mount_point) { +void* +__dup_pagetable(pid_t pid, uintptr_t mount_point) +{ void* ptd_pp = pmm_alloc_page(pid, PP_FGPERSIST); - x86_page_table* ptd = vmm_fmap_page(pid, PG_MOUNT_1, ptd_pp, PG_PREM_RW); - x86_page_table* pptd = (x86_page_table*) (mount_point | (0x3FF << 12)); + vmm_set_mapping(PD_REFERENCED, PG_MOUNT_1, ptd_pp, PG_PREM_RW, VMAP_NULL); - for (size_t i = 0; i < PG_MAX_ENTRIES - 1; i++) - { + x86_page_table* ptd = PG_MOUNT_1; + x86_page_table* pptd = (x86_page_table*)(mount_point | (0x3FF << 12)); + + for (size_t i = 0; i < PG_MAX_ENTRIES - 1; i++) { x86_pte_t ptde = pptd->entry[i]; if (!ptde || !(ptde & PG_PRESENT)) { ptd->entry[i] = ptde; continue; } - - x86_page_table* ppt = (x86_page_table*) (mount_point | (i << 12)); + void* pt_pp = pmm_alloc_page(pid, PP_FGPERSIST); - x86_page_table* pt = vmm_fmap_page(pid, PG_MOUNT_2, pt_pp, PG_PREM_RW); + vmm_set_mapping( + PD_REFERENCED, PG_MOUNT_2, pt_pp, PG_PREM_RW, VMAP_NULL); - for (size_t j = 0; j < PG_MAX_ENTRIES; j++) - { + x86_page_table* ppt = (x86_page_table*)(mount_point | (i << 12)); + x86_page_table* pt = PG_MOUNT_2; + + for (size_t j = 0; j < PG_MAX_ENTRIES; j++) { x86_pte_t pte = ppt->entry[j]; - pmm_ref_page(pid, pte & ~0xfff); + pmm_ref_page(pid, PG_ENTRY_ADDR(pte)); pt->entry[j] = pte; } ptd->entry[i] = (uintptr_t)pt_pp | PG_PREM_RW; } - + ptd->entry[PG_MAX_ENTRIES - 1] = NEW_L1_ENTRY(T_SELF_REF_PERM, ptd_pp); return ptd_pp; } -void* dup_pagetable(pid_t pid) { +void +__del_pagetable(pid_t pid, uintptr_t mount_point) +{ + x86_page_table* pptd = (x86_page_table*)(mount_point | (0x3FF << 12)); + + for (size_t i = 0; i < PG_MAX_ENTRIES - 1; i++) { + x86_pte_t ptde = pptd->entry[i]; + if (!ptde || !(ptde & PG_PRESENT)) { + continue; + } + + x86_page_table* ppt = (x86_page_table*)(mount_point | (i << 12)); + + for (size_t j = 0; j < PG_MAX_ENTRIES; j++) { + x86_pte_t pte = ppt->entry[j]; + // free the 4KB data page + if ((pte & PG_PRESENT)) { + pmm_free_page(pid, PG_ENTRY_ADDR(pte)); + } + } + // free the L2 page table + pmm_free_page(pid, PG_ENTRY_ADDR(ptde)); + } + // free the L1 directory + pmm_free_page(pid, PG_ENTRY_ADDR(pptd->entry[PG_MAX_ENTRIES - 1])); +} + +void* +dup_pagetable(pid_t pid) +{ return __dup_pagetable(pid, PD_REFERENCED); } -__DEFINE_LXSYSCALL(void, fork) { - dup_proc(); +__DEFINE_LXSYSCALL(pid_t, fork) +{ + return dup_proc(); } -__DEFINE_LXSYSCALL(pid_t, getpid) { +__DEFINE_LXSYSCALL(pid_t, getpid) +{ return __current->pid; } -__DEFINE_LXSYSCALL(pid_t, getppid) { +__DEFINE_LXSYSCALL(pid_t, getppid) +{ return __current->parent->pid; } -void dup_proc() { - pid_t pid = alloc_pid(); +__DEFINE_LXSYSCALL(pid_t, getpgid) +{ + return __current->pgid; +} + +__DEFINE_LXSYSCALL2(int, setpgid, pid_t, pid, pid_t, pgid) +{ + struct proc_info* proc = pid ? get_process(pid) : __current; + + if (!proc) { + __current->k_status = LXINVL; + return -1; + } + + pgid = pgid ? pgid : proc->pid; + + struct proc_info* gruppenfuhrer = get_process(pgid); + + if (!gruppenfuhrer || proc->pgid == proc->pid) { + __current->k_status = LXINVL; + return -1; + } + + llist_delete(&proc->grp_member); + llist_append(&gruppenfuhrer->grp_member, &proc->grp_member); + + proc->pgid = pgid; + return 0; +} + +void +init_proc(struct proc_info* pcb) +{ + memset(pcb, 0, sizeof(*pcb)); - struct proc_info pcb = (struct proc_info) { - .created = clock_systime(), - .pid = pid, - .mm = __current->mm, - .intr_ctx = __current->intr_ctx, - .parent = __current - }; + pcb->pid = alloc_pid(); + pcb->created = clock_systime(); + pcb->state = PROC_CREATED; + pcb->pgid = pcb->pid; +} - setup_proc_mem(&pcb, PD_MOUNT_1); //挂载点#1是当前进程的页表 +pid_t +dup_proc() +{ + struct proc_info pcb; + init_proc(&pcb); + pcb.mm = __current->mm; + pcb.intr_ctx = __current->intr_ctx; + pcb.parent = __current; + +#ifdef USE_KERNEL_PG + setup_proc_mem(&pcb, PD_MOUNT_1); //挂载点#1是当前进程的页表 +#else + setup_proc_mem(&pcb, PD_REFERENCED); +#endif // 根据 mm_region 进一步配置页表 - if (__current->mm.regions) { - struct mm_region *pos, *n; - llist_for_each(pos, n, &__current->mm.regions->head, head) { - region_add(&pcb, pos->start, pos->end, pos->attr); - - // 如果写共享,则不作处理。 - if ((pos->attr & REGION_WSHARED)) { - continue; - } + if (!__current->mm.regions) { + goto not_copy; + } - uintptr_t start_vpn = PG_ALIGN(pos->start) >> 12; - uintptr_t end_vpn = PG_ALIGN(pos->end) >> 12; - for (size_t i = start_vpn; i < end_vpn; i++) - { - x86_pte_t *curproc = &((x86_page_table*)(PD_MOUNT_1 | ((i & 0xffc00) << 2)))->entry[i & 0x3ff]; - x86_pte_t *newproc = &((x86_page_table*)(PD_MOUNT_2 | ((i & 0xffc00) << 2)))->entry[i & 0x3ff]; - - if (pos->attr == REGION_RSHARED) { - // 如果读共享,则将两者的都标注为只读,那么任何写入都将会应用COW策略。 - *curproc = *curproc & ~PG_WRITE; - *newproc = *newproc & ~PG_WRITE; - } - else { - // 如果是私有页,则将该页从新进程中移除。 - *newproc = 0; - } + llist_init_head(&pcb.mm.regions); + struct mm_region *pos, *n; + llist_for_each(pos, n, &__current->mm.regions->head, head) + { + region_add(&pcb, pos->start, pos->end, pos->attr); + + // 如果写共享,则不作处理。 + if ((pos->attr & REGION_WSHARED)) { + continue; + } + + uintptr_t start_vpn = PG_ALIGN(pos->start) >> 12; + uintptr_t end_vpn = PG_ALIGN(pos->end) >> 12; + for (size_t i = start_vpn; i < end_vpn; i++) { + x86_pte_t* curproc = &PTE_MOUNTED(PD_MOUNT_1, i); + x86_pte_t* newproc = &PTE_MOUNTED(PD_MOUNT_2, i); + cpu_invplg(newproc); + + if (pos->attr == REGION_RSHARED) { + // 如果读共享,则将两者的都标注为只读,那么任何写入都将会应用COW策略。 + cpu_invplg(curproc); + *curproc = *curproc & ~PG_WRITE; + *newproc = *newproc & ~PG_WRITE; + } else { + // 如果是私有页,则将该页从新进程中移除。 + *newproc = 0; } } } - + +not_copy: vmm_unmount_pd(PD_MOUNT_2); // 正如同fork,返回两次。 pcb.intr_ctx.registers.eax = 0; - __current->intr_ctx.registers.eax = pid; push_process(&pcb); + + return pcb.pid; } extern void __kernel_end; -void setup_proc_mem(struct proc_info* proc, uintptr_t usedMnt) { +void +setup_proc_mem(struct proc_info* proc, uintptr_t usedMnt) +{ // copy the entire kernel page table pid_t pid = proc->pid; void* pt_copy = __dup_pagetable(pid, usedMnt); - vmm_mount_pd(PD_MOUNT_2, pt_copy); // 将新进程的页表挂载到挂载点#2 + vmm_mount_pd(PD_MOUNT_2, pt_copy); // 将新进程的页表挂载到挂载点#2 // copy the kernel stack - for (size_t i = KSTACK_START >> 12; i <= KSTACK_TOP >> 12; i++) - { - x86_pte_t *ppte = &((x86_page_table*)(PD_MOUNT_2 | ((i & 0xffc00) << 2)))->entry[i & 0x3ff]; - void* ppa = vmm_dup_page(pid, PG_ENTRY_ADDR(*ppte)); - *ppte = (*ppte & 0xfff) | (uintptr_t)ppa; + for (size_t i = KSTACK_START >> 12; i <= KSTACK_TOP >> 12; i++) { + volatile x86_pte_t* ppte = &PTE_MOUNTED(PD_MOUNT_2, i); + + /* + This is a fucking nightmare, the TLB caching keep the rewrite to PTE + from updating. Even the Nightmare Moon the Evil is far less nasty + than this. It took me hours of debugging to figure this out. + + In the name of Celestia our glorious goddess, I will fucking HATE + the TLB for the rest of my LIFE! + */ + cpu_invplg(ppte); + + x86_pte_t p = *ppte; + void* ppa = vmm_dup_page(pid, PG_ENTRY_ADDR(p)); + *ppte = (p & 0xfff) | (uintptr_t)ppa; } // 我们不需要分配内核的区域,因为所有的内核代码和数据段只能通过系统调用来访问,任何非法的访问 // 都会导致eip落在区域外面,从而segmentation fault. - - // 定义用户栈区域,但是不分配实际的物理页。我们会在Page fault handler里面实现动态分配物理页的逻辑。(虚拟内存的好处!) + + // 定义用户栈区域,但是不分配实际的物理页。我们会在Page fault + // handler里面实现动态分配物理页的逻辑。(虚拟内存的好处!) // FIXME: 这里应该放到spawn_proc里面。 // region_add(proc, USTACK_END, USTACK_SIZE, REGION_PRIVATE | REGION_RW);