X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=kernel%2Ffork.c;h=28a74015198899c3511f3daedbb2412c750c4fe4;hb=4ed53a5af75d858bd224c2cdd7604e347a63218f;hp=163325af8179adc71c9fbce52a4ffcb6fe9bac56;hpb=3e26c149c358529b1605f8959341d34bc4b880a3;p=safe%2Fjmp%2Flinux-2.6 diff --git a/kernel/fork.c b/kernel/fork.c index 163325a..28a7401 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -29,7 +29,7 @@ #include #include #include -#include +#include #include #include #include @@ -50,6 +50,7 @@ #include #include #include +#include #include #include @@ -116,7 +117,7 @@ EXPORT_SYMBOL(free_task); void __put_task_struct(struct task_struct *tsk) { - WARN_ON(!(tsk->exit_state & (EXIT_DEAD | EXIT_ZOMBIE))); + WARN_ON(!tsk->exit_state); WARN_ON(atomic_read(&tsk->usage)); WARN_ON(tsk == current); @@ -205,7 +206,7 @@ static struct task_struct *dup_task_struct(struct task_struct *orig) } #ifdef CONFIG_MMU -static inline int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm) +static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm) { struct vm_area_struct *mpnt, *tmp, **pprev; struct rb_node **rb_link, *rb_parent; @@ -268,7 +269,7 @@ static inline int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm) get_file(file); if (tmp->vm_flags & VM_DENYWRITE) atomic_dec(&inode->i_writecount); - + /* insert tmp into the share list, just after mpnt */ spin_lock(&file->f_mapping->i_mmap_lock); tmp->vm_truncate_count = mpnt->vm_truncate_count; @@ -331,7 +332,7 @@ static inline void mm_free_pgd(struct mm_struct * mm) #define mm_free_pgd(mm) #endif /* CONFIG_MMU */ - __cacheline_aligned_in_smp DEFINE_SPINLOCK(mmlist_lock); +__cacheline_aligned_in_smp DEFINE_SPINLOCK(mmlist_lock); #define allocate_mm() (kmem_cache_alloc(mm_cachep, GFP_KERNEL)) #define free_mm(mm) (kmem_cache_free(mm_cachep, (mm))) @@ -583,7 +584,7 @@ fail_nomem: return retval; } -static inline struct fs_struct *__copy_fs_struct(struct fs_struct *old) +static struct fs_struct *__copy_fs_struct(struct fs_struct *old) { struct fs_struct *fs = kmem_cache_alloc(fs_cachep, GFP_KERNEL); /* We don't need to lock fs - think why ;-) */ @@ -615,7 +616,7 @@ struct fs_struct *copy_fs_struct(struct fs_struct *old) EXPORT_SYMBOL_GPL(copy_fs_struct); -static inline int copy_fs(unsigned long clone_flags, struct task_struct * tsk) +static int copy_fs(unsigned long clone_flags, struct task_struct *tsk) { if (clone_flags & CLONE_FS) { atomic_inc(¤t->fs->count); @@ -738,8 +739,8 @@ static struct files_struct *dup_fd(struct files_struct *oldf, int *errorp) /* compute the remainder to be cleared */ size = (new_fdt->max_fds - open_files) * sizeof(struct file *); - /* This is long word aligned thus could use a optimized version */ - memset(new_fds, 0, size); + /* This is long word aligned thus could use a optimized version */ + memset(new_fds, 0, size); if (new_fdt->max_fds > open_files) { int left = (new_fdt->max_fds-open_files)/8; @@ -818,7 +819,7 @@ int unshare_files(void) EXPORT_SYMBOL(unshare_files); -static inline int copy_sighand(unsigned long clone_flags, struct task_struct * tsk) +static int copy_sighand(unsigned long clone_flags, struct task_struct *tsk) { struct sighand_struct *sig; @@ -841,7 +842,7 @@ void __cleanup_sighand(struct sighand_struct *sighand) kmem_cache_free(sighand_cachep, sighand); } -static inline int copy_signal(unsigned long clone_flags, struct task_struct * tsk) +static int copy_signal(unsigned long clone_flags, struct task_struct *tsk) { struct signal_struct *sig; int ret; @@ -923,7 +924,7 @@ void __cleanup_signal(struct signal_struct *sig) kmem_cache_free(signal_cachep, sig); } -static inline void cleanup_signal(struct task_struct *tsk) +static void cleanup_signal(struct task_struct *tsk) { struct signal_struct *sig = tsk->signal; @@ -933,7 +934,7 @@ static inline void cleanup_signal(struct task_struct *tsk) __cleanup_signal(sig); } -static inline void copy_flags(unsigned long clone_flags, struct task_struct *p) +static void copy_flags(unsigned long clone_flags, struct task_struct *p) { unsigned long new_flags = p->flags; @@ -942,16 +943,17 @@ static inline void copy_flags(unsigned long clone_flags, struct task_struct *p) if (!(clone_flags & CLONE_PTRACE)) p->ptrace = 0; p->flags = new_flags; + clear_freeze_flag(p); } asmlinkage long sys_set_tid_address(int __user *tidptr) { current->clear_child_tid = tidptr; - return current->pid; + return task_pid_vnr(current); } -static inline void rt_mutex_init_task(struct task_struct *p) +static void rt_mutex_init_task(struct task_struct *p) { spin_lock_init(&p->pi_lock); #ifdef CONFIG_RT_MUTEXES @@ -972,12 +974,12 @@ static struct task_struct *copy_process(unsigned long clone_flags, unsigned long stack_start, struct pt_regs *regs, unsigned long stack_size, - int __user *parent_tidptr, int __user *child_tidptr, struct pid *pid) { int retval; - struct task_struct *p = NULL; + struct task_struct *p; + int cgroup_callbacks_done = 0; if ((clone_flags & (CLONE_NEWNS|CLONE_FS)) == (CLONE_NEWNS|CLONE_FS)) return ERR_PTR(-EINVAL); @@ -1041,12 +1043,6 @@ static struct task_struct *copy_process(unsigned long clone_flags, p->did_exec = 0; delayacct_tsk_init(p); /* Must remain after dup_task_struct() */ copy_flags(clone_flags, p); - p->pid = pid_nr(pid); - retval = -EFAULT; - if (clone_flags & CLONE_PARENT_SETTID) - if (put_user(p->pid, parent_tidptr)) - goto bad_fork_cleanup_delays_binfmt; - INIT_LIST_HEAD(&p->children); INIT_LIST_HEAD(&p->sibling); p->vfork_done = NULL; @@ -1058,6 +1054,10 @@ static struct task_struct *copy_process(unsigned long clone_flags, p->utime = cputime_zero; p->stime = cputime_zero; p->gtime = cputime_zero; + p->utimescaled = cputime_zero; + p->stimescaled = cputime_zero; + p->prev_utime = cputime_zero; + p->prev_stime = cputime_zero; #ifdef CONFIG_TASK_XACCT p->rchar = 0; /* I/O counter: bytes read */ @@ -1068,28 +1068,29 @@ static struct task_struct *copy_process(unsigned long clone_flags, task_io_accounting_init(p); acct_clear_integrals(p); - p->it_virt_expires = cputime_zero; + p->it_virt_expires = cputime_zero; p->it_prof_expires = cputime_zero; - p->it_sched_expires = 0; - INIT_LIST_HEAD(&p->cpu_timers[0]); - INIT_LIST_HEAD(&p->cpu_timers[1]); - INIT_LIST_HEAD(&p->cpu_timers[2]); + p->it_sched_expires = 0; + INIT_LIST_HEAD(&p->cpu_timers[0]); + INIT_LIST_HEAD(&p->cpu_timers[1]); + INIT_LIST_HEAD(&p->cpu_timers[2]); p->lock_depth = -1; /* -1 = no lock */ do_posix_clock_monotonic_gettime(&p->start_time); p->real_start_time = p->start_time; monotonic_to_bootbased(&p->real_start_time); +#ifdef CONFIG_SECURITY p->security = NULL; +#endif p->io_context = NULL; - p->io_wait = NULL; p->audit_context = NULL; - cpuset_fork(p); + cgroup_fork(p); #ifdef CONFIG_NUMA p->mempolicy = mpol_copy(p->mempolicy); if (IS_ERR(p->mempolicy)) { retval = PTR_ERR(p->mempolicy); p->mempolicy = NULL; - goto bad_fork_cleanup_cpuset; + goto bad_fork_cleanup_cgroup; } mpol_fix_fork_child_flag(p); #endif @@ -1122,10 +1123,6 @@ static struct task_struct *copy_process(unsigned long clone_flags, p->blocked_on = NULL; /* not blocked yet */ #endif - p->tgid = p->pid; - if (clone_flags & CLONE_THREAD) - p->tgid = current->tgid; - if ((retval = security_task_alloc(p))) goto bad_fork_cleanup_policy; if ((retval = audit_alloc(p))) @@ -1151,18 +1148,37 @@ static struct task_struct *copy_process(unsigned long clone_flags, if (retval) goto bad_fork_cleanup_namespaces; + if (pid != &init_struct_pid) { + retval = -ENOMEM; + pid = alloc_pid(task_active_pid_ns(p)); + if (!pid) + goto bad_fork_cleanup_namespaces; + + if (clone_flags & CLONE_NEWPID) { + retval = pid_ns_prepare_proc(task_active_pid_ns(p)); + if (retval < 0) + goto bad_fork_free_pid; + } + } + + p->pid = pid_nr(pid); + p->tgid = p->pid; + if (clone_flags & CLONE_THREAD) + p->tgid = current->tgid; + p->set_child_tid = (clone_flags & CLONE_CHILD_SETTID) ? child_tidptr : NULL; /* * Clear TID on mm_release()? */ p->clear_child_tid = (clone_flags & CLONE_CHILD_CLEARTID) ? child_tidptr: NULL; +#ifdef CONFIG_FUTEX p->robust_list = NULL; #ifdef CONFIG_COMPAT p->compat_robust_list = NULL; #endif INIT_LIST_HEAD(&p->pi_state_list); p->pi_state_cache = NULL; - +#endif /* * sigaltstack should be cleared when sharing the same VM */ @@ -1199,6 +1215,12 @@ static struct task_struct *copy_process(unsigned long clone_flags, /* Perform scheduler related setup. Assign this task to a CPU. */ sched_fork(p, clone_flags); + /* Now that the task is set up, run cgroup callbacks if + * necessary. We need to run them before the task is visible + * on the tasklist. */ + cgroup_fork_callbacks(p); + cgroup_callbacks_done = 1; + /* Need tasklist lock for parent etc handling! */ write_lock_irq(&tasklist_lock); @@ -1236,12 +1258,12 @@ static struct task_struct *copy_process(unsigned long clone_flags, * A fatal signal pending means that current will exit, so the new * thread can't slip out of an OOM kill (or normal SIGKILL). */ - recalc_sigpending(); + recalc_sigpending(); if (signal_pending(current)) { spin_unlock(¤t->sighand->siglock); write_unlock_irq(&tasklist_lock); retval = -ERESTARTNOINTR; - goto bad_fork_cleanup_namespaces; + goto bad_fork_free_pid; } if (clone_flags & CLONE_THREAD) { @@ -1270,11 +1292,22 @@ static struct task_struct *copy_process(unsigned long clone_flags, __ptrace_link(p, current->parent); if (thread_group_leader(p)) { - p->signal->tty = current->signal->tty; - p->signal->pgrp = process_group(current); - set_signal_session(p->signal, process_session(current)); - attach_pid(p, PIDTYPE_PGID, task_pgrp(current)); - attach_pid(p, PIDTYPE_SID, task_session(current)); + if (clone_flags & CLONE_NEWPID) { + p->nsproxy->pid_ns->child_reaper = p; + p->signal->tty = NULL; + set_task_pgrp(p, p->pid); + set_task_session(p, p->pid); + attach_pid(p, PIDTYPE_PGID, pid); + attach_pid(p, PIDTYPE_SID, pid); + } else { + p->signal->tty = current->signal->tty; + set_task_pgrp(p, task_pgrp_nr(current)); + set_task_session(p, task_session_nr(current)); + attach_pid(p, PIDTYPE_PGID, + task_pgrp(current)); + attach_pid(p, PIDTYPE_SID, + task_session(current)); + } list_add_tail_rcu(&p->tasks, &init_task.tasks); __get_cpu_var(process_counts)++; @@ -1287,8 +1320,12 @@ static struct task_struct *copy_process(unsigned long clone_flags, spin_unlock(¤t->sighand->siglock); write_unlock_irq(&tasklist_lock); proc_fork_connector(p); + cgroup_post_fork(p); return p; +bad_fork_free_pid: + if (pid != &init_struct_pid) + free_pid(pid); bad_fork_cleanup_namespaces: exit_task_namespaces(p); bad_fork_cleanup_keys: @@ -1313,10 +1350,9 @@ bad_fork_cleanup_security: bad_fork_cleanup_policy: #ifdef CONFIG_NUMA mpol_free(p->mempolicy); -bad_fork_cleanup_cpuset: +bad_fork_cleanup_cgroup: #endif - cpuset_exit(p); -bad_fork_cleanup_delays_binfmt: + cgroup_exit(p, cgroup_callbacks_done); delayacct_tsk_free(p); if (p->binfmt) module_put(p->binfmt->module); @@ -1343,7 +1379,7 @@ struct task_struct * __cpuinit fork_idle(int cpu) struct task_struct *task; struct pt_regs regs; - task = copy_process(CLONE_VM, 0, idle_regs(®s), 0, NULL, NULL, + task = copy_process(CLONE_VM, 0, idle_regs(®s), 0, NULL, &init_struct_pid); if (!IS_ERR(task)) init_idle(task, cpu); @@ -1351,7 +1387,7 @@ struct task_struct * __cpuinit fork_idle(int cpu) return task; } -static inline int fork_traceflag (unsigned clone_flags) +static int fork_traceflag(unsigned clone_flags) { if (clone_flags & CLONE_UNTRACED) return 0; @@ -1382,19 +1418,16 @@ long do_fork(unsigned long clone_flags, { struct task_struct *p; int trace = 0; - struct pid *pid = alloc_pid(); long nr; - if (!pid) - return -EAGAIN; - nr = pid->nr; if (unlikely(current->ptrace)) { trace = fork_traceflag (clone_flags); if (trace) clone_flags |= CLONE_PTRACE; } - p = copy_process(clone_flags, stack_start, regs, stack_size, parent_tidptr, child_tidptr, pid); + p = copy_process(clone_flags, stack_start, regs, stack_size, + child_tidptr, NULL); /* * Do this prior waking up the new thread - the thread pointer * might get invalid after that point, if the thread exits quickly. @@ -1402,6 +1435,17 @@ long do_fork(unsigned long clone_flags, if (!IS_ERR(p)) { struct completion vfork; + /* + * this is enough to call pid_nr_ns here, but this if + * improves optimisation of regular fork() + */ + nr = (clone_flags & CLONE_NEWPID) ? + task_pid_nr_ns(p, current->nsproxy->pid_ns) : + task_pid_vnr(p); + + if (clone_flags & CLONE_PARENT_SETTID) + put_user(nr, parent_tidptr); + if (clone_flags & CLONE_VFORK) { p->vfork_done = &vfork; init_completion(&vfork); @@ -1435,7 +1479,6 @@ long do_fork(unsigned long clone_flags, } } } else { - free_pid(pid); nr = PTR_ERR(p); } return nr; @@ -1445,8 +1488,7 @@ long do_fork(unsigned long clone_flags, #define ARCH_MIN_MMSTRUCT_ALIGN 0 #endif -static void sighand_ctor(void *data, struct kmem_cache *cachep, - unsigned long flags) +static void sighand_ctor(struct kmem_cache *cachep, void *data) { struct sighand_struct *sighand = data; @@ -1481,7 +1523,7 @@ void __init proc_caches_init(void) * Check constraints on flags passed to the unshare system call and * force unsharing of additional process context as appropriate. */ -static inline void check_unshare_flags(unsigned long *flags_ptr) +static void check_unshare_flags(unsigned long *flags_ptr) { /* * If unsharing a thread from a thread group, must also @@ -1613,7 +1655,7 @@ asmlinkage long sys_unshare(unsigned long unshare_flags) struct mm_struct *mm, *new_mm = NULL, *active_mm = NULL; struct files_struct *fd, *new_fd = NULL; struct sem_undo_list *new_ulist = NULL; - struct nsproxy *new_nsproxy = NULL, *old_nsproxy = NULL; + struct nsproxy *new_nsproxy = NULL; check_unshare_flags(&unshare_flags); @@ -1643,14 +1685,13 @@ asmlinkage long sys_unshare(unsigned long unshare_flags) if (new_fs || new_mm || new_fd || new_ulist || new_nsproxy) { - task_lock(current); - if (new_nsproxy) { - old_nsproxy = current->nsproxy; - current->nsproxy = new_nsproxy; - new_nsproxy = old_nsproxy; + switch_task_namespaces(current, new_nsproxy); + new_nsproxy = NULL; } + task_lock(current); + if (new_fs) { fs = current->fs; current->fs = new_fs;