X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=include%2Flinux%2Fpid.h;h=49f1c2f66e951bc7e226a5809450af8714c80473;hb=609162850db11dfe3b23f43b36888aa8b3ad7685;hp=c5fee61bfb4f9c691eeadbf07b48e741b7483d01;hpb=7af5729474b5b8ad385adadab78d6e723e7655a3;p=safe%2Fjmp%2Flinux-2.6 diff --git a/include/linux/pid.h b/include/linux/pid.h index c5fee61..49f1c2f 100644 --- a/include/linux/pid.h +++ b/include/linux/pid.h @@ -48,7 +48,7 @@ enum pid_type */ struct upid { - /* Try to keep pid_chain in the same cacheline as nr for find_pid */ + /* Try to keep pid_chain in the same cacheline as nr for find_vpid */ int nr; struct pid_namespace *ns; struct hlist_node pid_chain; @@ -57,13 +57,10 @@ struct upid { struct pid { atomic_t count; - /* Try to keep pid_chain in the same cacheline as nr for find_pid */ - int nr; - struct hlist_node pid_chain; + unsigned int level; /* lists of tasks that use this pid */ struct hlist_head tasks[PIDTYPE_MAX]; struct rcu_head rcu; - int level; struct upid numbers[1]; }; @@ -82,10 +79,9 @@ static inline struct pid *get_pid(struct pid *pid) return pid; } -extern void FASTCALL(put_pid(struct pid *pid)); -extern struct task_struct *FASTCALL(pid_task(struct pid *pid, enum pid_type)); -extern struct task_struct *FASTCALL(get_pid_task(struct pid *pid, - enum pid_type)); +extern void put_pid(struct pid *pid); +extern struct task_struct *pid_task(struct pid *pid, enum pid_type); +extern struct task_struct *get_pid_task(struct pid *pid, enum pid_type); extern struct pid *get_task_pid(struct task_struct *task, enum pid_type type); @@ -93,34 +89,63 @@ extern struct pid *get_task_pid(struct task_struct *task, enum pid_type type); * attach_pid() and detach_pid() must be called with the tasklist_lock * write-held. */ -extern int FASTCALL(attach_pid(struct task_struct *task, - enum pid_type type, struct pid *pid)); -extern void FASTCALL(detach_pid(struct task_struct *task, enum pid_type)); -extern void FASTCALL(transfer_pid(struct task_struct *old, - struct task_struct *new, enum pid_type)); +extern void attach_pid(struct task_struct *task, enum pid_type type, + struct pid *pid); +extern void detach_pid(struct task_struct *task, enum pid_type); +extern void change_pid(struct task_struct *task, enum pid_type, + struct pid *pid); +extern void transfer_pid(struct task_struct *old, struct task_struct *new, + enum pid_type); + +struct pid_namespace; +extern struct pid_namespace init_pid_ns; /* * look up a PID in the hash table. Must be called with the tasklist_lock * or rcu_read_lock() held. + * + * find_pid_ns() finds the pid in the namespace specified + * find_vpid() finr the pid by its virtual id, i.e. in the current namespace + * + * see also find_task_by_vpid() set in include/linux/sched.h */ -extern struct pid *FASTCALL(find_pid(int nr)); +extern struct pid *find_pid_ns(int nr, struct pid_namespace *ns); +extern struct pid *find_vpid(int nr); /* * Lookup a PID in the hash table, and return with it's count elevated. */ extern struct pid *find_get_pid(int nr); -extern struct pid *find_ge_pid(int nr); +extern struct pid *find_ge_pid(int nr, struct pid_namespace *); +int next_pidmap(struct pid_namespace *pid_ns, int last); extern struct pid *alloc_pid(struct pid_namespace *ns); -extern void FASTCALL(free_pid(struct pid *pid)); +extern void free_pid(struct pid *pid); + +/* + * ns_of_pid() returns the pid namespace in which the specified pid was + * allocated. + * + * NOTE: + * ns_of_pid() is expected to be called for a process (task) that has + * an attached 'struct pid' (see attach_pid(), detach_pid()) i.e @pid + * is expected to be non-NULL. If @pid is NULL, caller should handle + * the resulting NULL pid-ns. + */ +static inline struct pid_namespace *ns_of_pid(struct pid *pid) +{ + struct pid_namespace *ns = NULL; + if (pid) + ns = pid->numbers[pid->level].ns; + return ns; +} /* * the helpers to get the pid's id seen from different namespaces * * pid_nr() : global id, i.e. the id seen from the init namespace; - * pid_vnr() : virtual id, i.e. the id seen from the namespace this pid - * belongs to. this only makes sence when called in the - * context of the task that belongs to the same namespace; + * pid_vnr() : virtual id, i.e. the id seen from the pid namespace of + * current. * pid_nr_ns() : id seen from the ns specified. * * see also task_xid_nr() etc in include/linux/sched.h @@ -135,24 +160,32 @@ static inline pid_t pid_nr(struct pid *pid) } pid_t pid_nr_ns(struct pid *pid, struct pid_namespace *ns); - -static inline pid_t pid_vnr(struct pid *pid) -{ - pid_t nr = 0; - if (pid) - nr = pid->numbers[pid->level].nr; - return nr; -} +pid_t pid_vnr(struct pid *pid); #define do_each_pid_task(pid, type, task) \ do { \ struct hlist_node *pos___; \ - if (pid != NULL) \ + if ((pid) != NULL) \ hlist_for_each_entry_rcu((task), pos___, \ - &pid->tasks[type], pids[type].node) { + &(pid)->tasks[type], pids[type].node) { + /* + * Both old and new leaders may be attached to + * the same pid in the middle of de_thread(). + */ #define while_each_pid_task(pid, type, task) \ + if (type == PIDTYPE_PID) \ + break; \ } \ } while (0) +#define do_each_pid_thread(pid, type, task) \ + do_each_pid_task(pid, type, task) { \ + struct task_struct *tg___ = task; \ + do { + +#define while_each_pid_thread(pid, type, task) \ + } while_each_thread(tg___, task); \ + task = tg___; \ + } while_each_pid_task(pid, type, task) #endif /* _LINUX_PID_H */