/* * Allocate a new mm structure and copy contents from the * mm structure of the passed in task structure. */ struct mm_struct *dup_mm(struct task_struct *tsk) { struct mm_struct *mm, *oldmm = current->mm; int err; if (!oldmm) return NULL; mm = allocate_mm(); if (!mm) goto fail_nomem; memcpy(mm, oldmm, sizeof(*mm)); mm_init_cpumask(mm); #ifdef CONFIG_TRANSPARENT_HUGEPAGE mm->pmd_huge_pte = NULL; #endif uprobe_reset_state(mm); if (!mm_init(mm, tsk)) goto fail_nomem; if (init_new_context(tsk, mm)) goto fail_nocontext; dup_mm_exe_file(oldmm, mm); err = dup_mmap(mm, oldmm); if (err) goto free_pt; mm->hiwater_rss = get_mm_rss(mm); mm->hiwater_vm = mm->total_vm; if (mm->binfmt && !try_module_get(mm->binfmt->module)) goto free_pt; return mm; free_pt: /* don't put binfmt in mmput, we haven't got module yet */ mm->binfmt = NULL; mmput(mm); fail_nomem: return NULL; fail_nocontext: /* * If init_new_context() failed, we cannot use mmput() to free the mm * because it calls destroy_context() */ mm_free_pgd(mm); free_mm(mm); return NULL; }
/* * Allocate a new mm structure and copy contents from the * mm structure of the passed in task structure. */ struct mm_struct *dup_mm(struct task_struct *tsk) { struct mm_struct *mm, *oldmm = current->mm; int err; if (!oldmm) return NULL; mm = allocate_mm(); if (!mm) goto fail_nomem; memcpy(mm, oldmm, sizeof(*mm)); mm_init_cpumask(mm); /* Initializing for Swap token stuff */ mm->token_priority = 0; mm->last_interval = 0; #ifdef CONFIG_TRANSPARENT_HUGEPAGE mm->pmd_huge_pte = NULL; #endif uprobe_reset_state(mm); if (!mm_init(mm, tsk)) goto fail_nomem; if (init_new_context(tsk, mm)) goto fail_nocontext; dup_mm_exe_file(oldmm, mm); err = dup_mmap(mm, oldmm); if (err) goto free_pt; #ifdef CONFIG_HOMECACHE { /* Reset vm_pid on all vmas. In the new mm_struct, we * want to switch anything that was associated with * the parent to be associated with the child, and * clear everything else. */ struct vm_area_struct *mpnt; down_write_nested(&mm->mmap_sem, SINGLE_DEPTH_NESTING); for (mpnt = mm->mmap; mpnt; mpnt = mpnt->vm_next) { if (mpnt->vm_pid == current->pid) mpnt->vm_pid = tsk->pid; else mpnt->vm_pid = 0; } up_write(&mm->mmap_sem); } #endif mm->hiwater_rss = get_mm_rss(mm); mm->hiwater_vm = mm->total_vm; if (mm->binfmt && !try_module_get(mm->binfmt->module)) goto free_pt; return mm; free_pt: /* don't put binfmt in mmput, we haven't got module yet */ mm->binfmt = NULL; mmput(mm); fail_nomem: return NULL; fail_nocontext: /* * If init_new_context() failed, we cannot use mmput() to free the mm * because it calls destroy_context() */ mm_free_pgd(mm); free_mm(mm); return NULL; }