// copy_mm - process "proc" duplicate OR share process "current"'s mm according clone_flags // - if clone_flags & CLONE_VM, then "share" ; else "duplicate" static int copy_mm(uint32_t clone_flags, struct proc_struct *proc) { struct mm_struct *mm, *oldmm = current->mm; /* current is a kernel thread */ if (oldmm == NULL) { return 0; } if (clone_flags & CLONE_VM) { mm = oldmm; goto good_mm; } int ret = -E_NO_MEM; if ((mm = mm_create()) == NULL) { goto bad_mm; } if (setup_pgdir(mm) != 0) { goto bad_pgdir_cleanup_mm; } lock_mm(oldmm); { ret = dup_mmap(mm, oldmm); } unlock_mm(oldmm); if (ret != 0) { goto bad_dup_cleanup_mmap; } good_mm: if (mm != oldmm) { mm->brk_start = oldmm->brk_start; mm->brk = oldmm->brk; bool intr_flag; local_intr_save(intr_flag); { list_add(&(proc_mm_list), &(mm->proc_mm_link)); } local_intr_restore(intr_flag); } mm_count_inc(mm); proc->mm = mm; set_pgdir (proc, mm->pgdir); return 0; bad_dup_cleanup_mmap: exit_mmap(mm); put_pgdir(mm); bad_pgdir_cleanup_mm: mm_destroy(mm); bad_mm: return ret; }
int do_execve(const char *filename, const char **argv, const char **envp) { static_assert(EXEC_MAX_ARG_LEN >= FS_MAX_FPATH_LEN); struct mm_struct *mm = current->mm; char local_name[PROC_NAME_LEN + 1]; memset(local_name, 0, sizeof(local_name)); char *kargv[EXEC_MAX_ARG_NUM], *kenvp[EXEC_MAX_ENV_NUM]; const char *path; int ret = -E_INVAL; lock_mm(mm); #if 0 if (name == NULL) { snprintf(local_name, sizeof(local_name), "<null> %d", current->pid); } else { if (!copy_string(mm, local_name, name, sizeof(local_name))) { unlock_mm(mm); return ret; } } #endif snprintf(local_name, sizeof(local_name), "<null> %d", current->pid); int argc = 0, envc = 0; if ((ret = copy_kargv(mm, kargv, argv, EXEC_MAX_ARG_NUM, &argc)) != 0) { unlock_mm(mm); return ret; } if ((ret = copy_kargv(mm, kenvp, envp, EXEC_MAX_ENV_NUM, &envc)) != 0) { unlock_mm(mm); put_kargv(argc, kargv); return ret; } #if 0 int i; kprintf("## fn %s\n", filename); kprintf("## argc %d\n", argc); for(i=0;i<argc;i++) kprintf("## %08x %s\n", kargv[i], kargv[i]); kprintf("## envc %d\n", envc); for(i=0;i<envc;i++) kprintf("## %08x %s\n", kenvp[i], kenvp[i]); #endif //path = argv[0]; //copy_from_user (mm, &path, argv, sizeof (char*), 0); path = filename; unlock_mm(mm); /* linux never do this */ //fs_closeall(current->fs_struct); /* sysfile_open will check the first argument path, thus we have to use a user-space pointer, and argv[0] may be incorrect */ int fd; if ((ret = fd = sysfile_open(path, O_RDONLY)) < 0) { goto execve_exit; } if (mm != NULL) { mm->lapic = -1; mp_set_mm_pagetable(NULL); if (mm_count_dec(mm) == 0) { exit_mmap(mm); put_pgdir(mm); bool intr_flag; local_intr_save(intr_flag); { list_del(&(mm->proc_mm_link)); } local_intr_restore(intr_flag); mm_destroy(mm); } current->mm = NULL; } put_sem_queue(current); ret = -E_NO_MEM; /* init signal */ put_sighand(current); if ((current->signal_info.sighand = sighand_create()) == NULL) { goto execve_exit; } sighand_count_inc(current->signal_info.sighand); put_signal(current); if ((current->signal_info.signal = signal_create()) == NULL) { goto execve_exit; } signal_count_inc(current->signal_info.signal); if ((current->sem_queue = sem_queue_create()) == NULL) { goto execve_exit; } sem_queue_count_inc(current->sem_queue); if ((ret = load_icode(fd, argc, kargv, envc, kenvp)) != 0) { goto execve_exit; } set_proc_name(current, local_name); if (do_execve_arch_hook (argc, kargv) < 0) goto execve_exit; put_kargv(argc, kargv); return 0; execve_exit: put_kargv(argc, kargv); put_kargv(envc, kenvp); /* exec should return -1 if failed */ //return ret; do_exit(ret); panic("already exit: %e.\n", ret); }
static int load_icode(int fd, int argc, char **kargv, int envc, char **kenvp) { assert(argc >= 0 && argc <= EXEC_MAX_ARG_NUM); assert(envc >= 0 && envc <= EXEC_MAX_ENV_NUM); if (current->mm != NULL) { panic("load_icode: current->mm must be empty.\n"); } int ret = -E_NO_MEM; struct mm_struct *mm; if ((mm = mm_create()) == NULL) { goto bad_mm; } if (setup_pgdir(mm) != 0) { goto bad_pgdir_cleanup_mm; } mm->brk_start = 0; struct Page *page; struct elfhdr __elf, *elf = &__elf; if ((ret = load_icode_read(fd, elf, sizeof(struct elfhdr), 0)) != 0) { goto bad_elf_cleanup_pgdir; } if (elf->e_magic != ELF_MAGIC) { ret = -E_INVAL_ELF; goto bad_elf_cleanup_pgdir; } struct proghdr __ph, *ph = &__ph; uint32_t vm_flags, phnum; pte_perm_t perm = 0; for (phnum = 0; phnum < elf->e_phnum; phnum ++) { off_t phoff = elf->e_phoff + sizeof(struct proghdr) * phnum; if ((ret = load_icode_read(fd, ph, sizeof(struct proghdr), phoff)) != 0) { goto bad_cleanup_mmap; } if (ph->p_type != ELF_PT_LOAD) { continue ; } if (ph->p_filesz > ph->p_memsz) { ret = -E_INVAL_ELF; goto bad_cleanup_mmap; } vm_flags = 0; ptep_set_u_read(&perm); if (ph->p_flags & ELF_PF_X) vm_flags |= VM_EXEC; if (ph->p_flags & ELF_PF_W) vm_flags |= VM_WRITE; if (ph->p_flags & ELF_PF_R) vm_flags |= VM_READ; if (vm_flags & VM_WRITE) ptep_set_u_write(&perm); if ((ret = mm_map(mm, ph->p_va, ph->p_memsz, vm_flags, NULL)) != 0) { goto bad_cleanup_mmap; } if (mm->brk_start < ph->p_va + ph->p_memsz) { mm->brk_start = ph->p_va + ph->p_memsz; } off_t offset = ph->p_offset; size_t off, size; uintptr_t start = ph->p_va, end, la = ROUNDDOWN(start, PGSIZE); end = ph->p_va + ph->p_filesz; while (start < end) { if ((page = pgdir_alloc_page(mm->pgdir, la, perm)) == NULL) { ret = -E_NO_MEM; goto bad_cleanup_mmap; } off = start - la, size = PGSIZE - off, la += PGSIZE; if (end < la) { size -= la - end; } if ((ret = load_icode_read(fd, page2kva(page) + off, size, offset)) != 0) { goto bad_cleanup_mmap; } start += size, offset += size; } end = ph->p_va + ph->p_memsz; if (start < la) { /* ph->p_memsz == ph->p_filesz */ if (start == end) { continue ; } off = start + PGSIZE - la, size = PGSIZE - off; if (end < la) { size -= la - end; } memset(page2kva(page) + off, 0, size); start += size; assert((end < la && start == end) || (end >= la && start == la)); } while (start < end) { if ((page = pgdir_alloc_page(mm->pgdir, la, perm)) == NULL) { ret = -E_NO_MEM; goto bad_cleanup_mmap; } off = start - la, size = PGSIZE - off, la += PGSIZE; if (end < la) { size -= la - end; } memset(page2kva(page) + off, 0, size); start += size; } } sysfile_close(fd); mm->brk_start = mm->brk = ROUNDUP(mm->brk_start, PGSIZE); /* setup user stack */ vm_flags = VM_READ | VM_WRITE | VM_STACK; if ((ret = mm_map(mm, USTACKTOP - USTACKSIZE, USTACKSIZE, vm_flags, NULL)) != 0) { goto bad_cleanup_mmap; } bool intr_flag; local_intr_save(intr_flag); { list_add(&(proc_mm_list), &(mm->proc_mm_link)); } local_intr_restore(intr_flag); mm_count_inc(mm); current->mm = mm; set_pgdir(current, mm->pgdir); mm->lapic = pls_read(lapic_id); mp_set_mm_pagetable(mm); if (init_new_context (current, elf, argc, kargv, envc, kenvp) < 0) goto bad_cleanup_mmap; ret = 0; out: return ret; bad_cleanup_mmap: exit_mmap(mm); bad_elf_cleanup_pgdir: put_pgdir(mm); bad_pgdir_cleanup_mm: mm_destroy(mm); bad_mm: goto out; }
// __do_exit - cause a thread exit (use do_exit, do_exit_thread instead) // 1. call exit_mmap & put_pgdir & mm_destroy to free the almost all memory space of process // 2. set process' state as PROC_ZOMBIE, then call wakeup_proc(parent) to ask parent reclaim itself. // 3. call scheduler to switch to other process static int __do_exit(void) { if (current == idleproc) { panic("idleproc exit.\n"); } if (current == initproc) { panic("initproc exit.\n"); } struct mm_struct *mm = current->mm; if (mm != NULL) { mm->lapic = -1; mp_set_mm_pagetable(NULL); if (mm_count_dec(mm) == 0) { exit_mmap(mm); put_pgdir(mm); bool intr_flag; local_intr_save(intr_flag); { list_del(&(mm->proc_mm_link)); } local_intr_restore(intr_flag); mm_destroy(mm); } current->mm = NULL; } put_sighand(current); put_signal(current); put_fs(current); put_sem_queue(current); current->state = PROC_ZOMBIE; bool intr_flag; struct proc_struct *proc, *parent; local_intr_save(intr_flag); { proc = parent = current->parent; do { if (proc->wait_state == WT_CHILD) { wakeup_proc(proc); } proc = next_thread(proc); } while (proc != parent); if ((parent = next_thread(current)) == current) { parent = initproc; } de_thread(current); while (current->cptr != NULL) { proc = current->cptr; current->cptr = proc->optr; proc->yptr = NULL; if ((proc->optr = parent->cptr) != NULL) { parent->cptr->yptr = proc; } proc->parent = parent; parent->cptr = proc; if (proc->state == PROC_ZOMBIE) { if (parent->wait_state == WT_CHILD) { wakeup_proc(parent); } } } } wakeup_queue(&(current->event_box.wait_queue), WT_INTERRUPTED, 1); local_intr_restore(intr_flag); schedule(); panic("__do_exit will not return!! %d %d.\n", current->pid, current->exit_code); }
static int load_icode(int fd, int argc, char **kargv, int envc, char **kenvp) { assert(argc >= 0 && argc <= EXEC_MAX_ARG_NUM); assert(envc >= 0 && envc <= EXEC_MAX_ENV_NUM); if (current->mm != NULL) { panic("load_icode: current->mm must be empty.\n"); } int ret = -E_NO_MEM; //#ifdef UCONFIG_BIONIC_LIBC uint32_t real_entry; //#endif //UCONFIG_BIONIC_LIBC struct mm_struct *mm; if ((mm = mm_create()) == NULL) { goto bad_mm; } if (setup_pgdir(mm) != 0) { goto bad_pgdir_cleanup_mm; } mm->brk_start = 0; struct Page *page; struct elfhdr __elf, *elf = &__elf; if ((ret = load_icode_read(fd, elf, sizeof(struct elfhdr), 0)) != 0) { goto bad_elf_cleanup_pgdir; } if (elf->e_magic != ELF_MAGIC) { ret = -E_INVAL_ELF; goto bad_elf_cleanup_pgdir; } //#ifdef UCONFIG_BIONIC_LIBC real_entry = elf->e_entry; uint32_t load_address, load_address_flag = 0; //#endif //UCONFIG_BIONIC_LIBC struct proghdr __ph, *ph = &__ph; uint32_t vm_flags, phnum; pte_perm_t perm = 0; //#ifdef UCONFIG_BIONIC_LIBC uint32_t is_dynamic = 0, interp_idx; uint32_t bias = 0; //#endif //UCONFIG_BIONIC_LIBC for (phnum = 0; phnum < elf->e_phnum; phnum++) { off_t phoff = elf->e_phoff + sizeof(struct proghdr) * phnum; if ((ret = load_icode_read(fd, ph, sizeof(struct proghdr), phoff)) != 0) { goto bad_cleanup_mmap; } if (ph->p_type == ELF_PT_INTERP) { is_dynamic = 1; interp_idx = phnum; continue; } if (ph->p_type != ELF_PT_LOAD) { continue; } if (ph->p_filesz > ph->p_memsz) { ret = -E_INVAL_ELF; goto bad_cleanup_mmap; } if (ph->p_va == 0 && !bias) { bias = 0x00008000; } if ((ret = map_ph(fd, ph, mm, &bias, 0)) != 0) { kprintf("load address: 0x%08x size: %d\n", ph->p_va, ph->p_memsz); goto bad_cleanup_mmap; } if (load_address_flag == 0) load_address = ph->p_va + bias; ++load_address_flag; /*********************************************/ /* vm_flags = 0; ptep_set_u_read(&perm); if (ph->p_flags & ELF_PF_X) vm_flags |= VM_EXEC; if (ph->p_flags & ELF_PF_W) vm_flags |= VM_WRITE; if (ph->p_flags & ELF_PF_R) vm_flags |= VM_READ; if (vm_flags & VM_WRITE) ptep_set_u_write(&perm); if ((ret = mm_map(mm, ph->p_va, ph->p_memsz, vm_flags, NULL)) != 0) { goto bad_cleanup_mmap; } if (mm->brk_start < ph->p_va + ph->p_memsz) { mm->brk_start = ph->p_va + ph->p_memsz; } off_t offset = ph->p_offset; size_t off, size; uintptr_t start = ph->p_va, end, la = ROUNDDOWN(start, PGSIZE); end = ph->p_va + ph->p_filesz; while (start < end) { if ((page = pgdir_alloc_page(mm->pgdir, la, perm)) == NULL) { ret = -E_NO_MEM; goto bad_cleanup_mmap; } off = start - la, size = PGSIZE - off, la += PGSIZE; if (end < la) { size -= la - end; } if ((ret = load_icode_read(fd, page2kva(page) + off, size, offset)) != 0) { goto bad_cleanup_mmap; } start += size, offset += size; } end = ph->p_va + ph->p_memsz; if (start < la) { // ph->p_memsz == ph->p_filesz if (start == end) { continue ; } off = start + PGSIZE - la, size = PGSIZE - off; if (end < la) { size -= la - end; } memset(page2kva(page) + off, 0, size); start += size; assert((end < la && start == end) || (end >= la && start == la)); } while (start < end) { if ((page = pgdir_alloc_page(mm->pgdir, la, perm)) == NULL) { ret = -E_NO_MEM; goto bad_cleanup_mmap; } off = start - la, size = PGSIZE - off, la += PGSIZE; if (end < la) { size -= la - end; } memset(page2kva(page) + off, 0, size); start += size; } */ /**************************************/ } mm->brk_start = mm->brk = ROUNDUP(mm->brk_start, PGSIZE); /* setup user stack */ vm_flags = VM_READ | VM_WRITE | VM_STACK; if ((ret = mm_map(mm, USTACKTOP - USTACKSIZE, USTACKSIZE, vm_flags, NULL)) != 0) { goto bad_cleanup_mmap; } if (is_dynamic) { elf->e_entry += bias; bias = 0; off_t phoff = elf->e_phoff + sizeof(struct proghdr) * interp_idx; if ((ret = load_icode_read(fd, ph, sizeof(struct proghdr), phoff)) != 0) { goto bad_cleanup_mmap; } char *interp_path = (char *)kmalloc(ph->p_filesz); load_icode_read(fd, interp_path, ph->p_filesz, ph->p_offset); int interp_fd = sysfile_open(interp_path, O_RDONLY); assert(interp_fd >= 0); struct elfhdr interp___elf, *interp_elf = &interp___elf; assert((ret = load_icode_read(interp_fd, interp_elf, sizeof(struct elfhdr), 0)) == 0); assert(interp_elf->e_magic == ELF_MAGIC); struct proghdr interp___ph, *interp_ph = &interp___ph; uint32_t interp_phnum; uint32_t va_min = 0xffffffff, va_max = 0; for (interp_phnum = 0; interp_phnum < interp_elf->e_phnum; ++interp_phnum) { off_t interp_phoff = interp_elf->e_phoff + sizeof(struct proghdr) * interp_phnum; assert((ret = load_icode_read(interp_fd, interp_ph, sizeof(struct proghdr), interp_phoff)) == 0); if (interp_ph->p_type != ELF_PT_LOAD) { continue; } if (va_min > interp_ph->p_va) va_min = interp_ph->p_va; if (va_max < interp_ph->p_va + interp_ph->p_memsz) va_max = interp_ph->p_va + interp_ph->p_memsz; } bias = get_unmapped_area(mm, va_max - va_min + 1 + PGSIZE); bias = ROUNDUP(bias, PGSIZE); for (interp_phnum = 0; interp_phnum < interp_elf->e_phnum; ++interp_phnum) { off_t interp_phoff = interp_elf->e_phoff + sizeof(struct proghdr) * interp_phnum; assert((ret = load_icode_read(interp_fd, interp_ph, sizeof(struct proghdr), interp_phoff)) == 0); if (interp_ph->p_type != ELF_PT_LOAD) { continue; } assert((ret = map_ph(interp_fd, interp_ph, mm, &bias, 1)) == 0); } real_entry = interp_elf->e_entry + bias; sysfile_close(interp_fd); kfree(interp_path); } sysfile_close(fd); bool intr_flag; local_intr_save(intr_flag); { list_add(&(proc_mm_list), &(mm->proc_mm_link)); } local_intr_restore(intr_flag); mm_count_inc(mm); current->mm = mm; set_pgdir(current, mm->pgdir); mm->cpuid = myid(); mp_set_mm_pagetable(mm); if (!is_dynamic) { real_entry += bias; } #ifdef UCONFIG_BIONIC_LIBC if (init_new_context_dynamic(current, elf, argc, kargv, envc, kenvp, is_dynamic, real_entry, load_address, bias) < 0) goto bad_cleanup_mmap; #else if (init_new_context(current, elf, argc, kargv, envc, kenvp) < 0) goto bad_cleanup_mmap; #endif //UCONFIG_BIONIC_LIBC ret = 0; out: return ret; bad_cleanup_mmap: exit_mmap(mm); bad_elf_cleanup_pgdir: put_pgdir(mm); bad_pgdir_cleanup_mm: mm_destroy(mm); bad_mm: goto out; }