* allocation scenario when all but one out of 1 million PIDs possible are
* allocated already: the scanning of 32 list entries and at most PAGE_SIZE
* bytes. The typical fastpath is a single successful setbit. Freeing is O(1).
+ *
+ * Pid namespaces:
+ * (C) 2007 Pavel Emelyanov <xemul@openvz.org>, OpenVZ, SWsoft Inc.
+ * (C) 2007 Sukadev Bhattiprolu <sukadev@us.ibm.com>, IBM
+ * Many thanks to Oleg Nesterov for comments and help
+ *
*/
#include <linux/mm.h>
#include <linux/hash.h>
#include <linux/pid_namespace.h>
#include <linux/init_task.h>
+#include <linux/syscalls.h>
#define pid_hashfn(nr, ns) \
hash_long((unsigned long)nr + (unsigned long)ns, pidhash_shift)
return -1;
}
-static int next_pidmap(struct pid_namespace *pid_ns, int last)
+int next_pidmap(struct pid_namespace *pid_ns, int last)
{
int offset;
struct pidmap *map, *end;
get_pid_ns(ns);
pid->level = ns->level;
- pid->nr = pid->numbers[0].nr;
atomic_set(&pid->count, 1);
for (type = 0; type < PIDTYPE_MAX; ++type)
INIT_HLIST_HEAD(&pid->tasks[type]);
}
EXPORT_SYMBOL_GPL(find_pid_ns);
+struct pid *find_vpid(int nr)
+{
+ return find_pid_ns(nr, current->nsproxy->pid_ns);
+}
+EXPORT_SYMBOL_GPL(find_vpid);
+
+struct pid *find_pid(int nr)
+{
+ return find_pid_ns(nr, &init_pid_ns);
+}
+EXPORT_SYMBOL_GPL(find_pid);
+
/*
* attach_pid() must be called with the tasklist_lock write-held.
*/
}
return result;
}
+EXPORT_SYMBOL(pid_task);
/*
* Must be called under rcu_read_lock() or with tasklist_lock read-held.
EXPORT_SYMBOL(find_task_by_pid_type_ns);
+struct task_struct *find_task_by_pid(pid_t nr)
+{
+ return find_task_by_pid_type_ns(PIDTYPE_PID, nr, &init_pid_ns);
+}
+EXPORT_SYMBOL(find_task_by_pid);
+
+struct task_struct *find_task_by_vpid(pid_t vnr)
+{
+ return find_task_by_pid_type_ns(PIDTYPE_PID, vnr,
+ current->nsproxy->pid_ns);
+}
+EXPORT_SYMBOL(find_task_by_vpid);
+
+struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns)
+{
+ return find_task_by_pid_type_ns(PIDTYPE_PID, nr, ns);
+}
+EXPORT_SYMBOL(find_task_by_pid_ns);
+
struct pid *get_task_pid(struct task_struct *task, enum pid_type type)
{
struct pid *pid;
return nr;
}
+pid_t task_pid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
+{
+ return pid_nr_ns(task_pid(tsk), ns);
+}
+EXPORT_SYMBOL(task_pid_nr_ns);
+
+pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
+{
+ return pid_nr_ns(task_tgid(tsk), ns);
+}
+EXPORT_SYMBOL(task_tgid_nr_ns);
+
+pid_t task_pgrp_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
+{
+ return pid_nr_ns(task_pgrp(tsk), ns);
+}
+EXPORT_SYMBOL(task_pgrp_nr_ns);
+
+pid_t task_session_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
+{
+ return pid_nr_ns(task_session(tsk), ns);
+}
+EXPORT_SYMBOL(task_session_nr_ns);
+
/*
* Used by proc to find the first pid that is greater then or equal to nr.
*
}
EXPORT_SYMBOL_GPL(find_get_pid);
-struct pid_cache {
- int nr_ids;
- char name[16];
- struct kmem_cache *cachep;
- struct list_head list;
-};
-
-static LIST_HEAD(pid_caches_lh);
-static DEFINE_MUTEX(pid_caches_mutex);
-
-/*
- * creates the kmem cache to allocate pids from.
- * @nr_ids: the number of numerical ids this pid will have to carry
- */
-
-static struct kmem_cache *create_pid_cachep(int nr_ids)
-{
- struct pid_cache *pcache;
- struct kmem_cache *cachep;
-
- mutex_lock(&pid_caches_mutex);
- list_for_each_entry (pcache, &pid_caches_lh, list)
- if (pcache->nr_ids == nr_ids)
- goto out;
-
- pcache = kmalloc(sizeof(struct pid_cache), GFP_KERNEL);
- if (pcache == NULL)
- goto err_alloc;
-
- snprintf(pcache->name, sizeof(pcache->name), "pid_%d", nr_ids);
- cachep = kmem_cache_create(pcache->name,
- /* FIXME add numerical ids here */
- sizeof(struct pid), 0, SLAB_HWCACHE_ALIGN, NULL);
- if (cachep == NULL)
- goto err_cachep;
-
- pcache->nr_ids = nr_ids;
- pcache->cachep = cachep;
- list_add(&pcache->list, &pid_caches_lh);
-out:
- mutex_unlock(&pid_caches_mutex);
- return pcache->cachep;
-
-err_cachep:
- kfree(pcache);
-err_alloc:
- mutex_unlock(&pid_caches_mutex);
- return NULL;
-}
-
-struct pid_namespace *copy_pid_ns(unsigned long flags, struct pid_namespace *old_ns)
-{
- BUG_ON(!old_ns);
- get_pid_ns(old_ns);
- return old_ns;
-}
-
-void free_pid_ns(struct kref *kref)
-{
- struct pid_namespace *ns;
-
- ns = container_of(kref, struct pid_namespace, kref);
- kfree(ns);
-}
-
/*
* The pid hash table is scaled according to the amount of memory in the
* machine. From a minimum of 16 slots up to 4096 slots at one gigabyte or
set_bit(0, init_pid_ns.pidmap[0].page);
atomic_dec(&init_pid_ns.pidmap[0].nr_free);
- init_pid_ns.pid_cachep = create_pid_cachep(1);
- if (init_pid_ns.pid_cachep == NULL)
- panic("Can't create pid_1 cachep\n");
+ init_pid_ns.pid_cachep = KMEM_CACHE(pid,
+ SLAB_HWCACHE_ALIGN | SLAB_PANIC);
}
projects / powerpc.git / blobdiff