1 files changed, 84 insertions, 49 deletions

diff --git a/kernel/fork.c b/kernel/fork.c
index 2ce28f165e31..ddafdfac9456 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -29,7 +29,7 @@
 #include <linux/nsproxy.h>
 #include <linux/capability.h>
 #include <linux/cpu.h>
-#include <linux/cpuset.h>
+#include <linux/cgroup.h>
 #include <linux/security.h>
 #include <linux/swap.h>
 #include <linux/syscalls.h>
@@ -50,6 +50,7 @@
 #include <linux/taskstats_kern.h>
 #include <linux/random.h>
 #include <linux/tty.h>
+#include <linux/proc_fs.h>
 
 #include <asm/pgtable.h>
 #include <asm/pgalloc.h>
@@ -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;
@@ -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(&current->fs->count);
@@ -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;
 
@@ -949,10 +950,10 @@ 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
@@ -973,12 +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);
@@ -1042,12 +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;
@@ -1087,13 +1082,13 @@ static struct task_struct *copy_process(unsigned long clone_flags,
 #endif
         p->io_context = 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
@@ -1126,10 +1121,6 @@ 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)))
@@ -1155,6 +1146,24 @@ 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()?
@@ -1204,6 +1213,12 @@ 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);
 
@@ -1246,7 +1261,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
                 spin_unlock(&current->sighand->siglock);
                 write_unlock_irq(&tasklist_lock);
                 retval = -ERESTARTNOINTR;
-                goto bad_fork_cleanup_namespaces;
+                goto bad_fork_free_pid;
         }
 
         if (clone_flags & CLONE_THREAD) {
@@ -1275,11 +1290,22 @@ 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)++;
@@ -1292,8 +1318,12 @@ static struct task_struct *copy_process(unsigned long clone_flags,
         spin_unlock(&current->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:
@@ -1318,10 +1348,9 @@ 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);
@@ -1348,7 +1377,7 @@ struct task_struct * __cpuinit fork_idle(int cpu)
         struct task_struct *task;
         struct pt_regs regs;
 
-        task = copy_process(CLONE_VM, 0, idle_regs(&regs), 0, NULL, NULL,
+        task = copy_process(CLONE_VM, 0, idle_regs(&regs), 0, NULL,
                                 &init_struct_pid);
         if (!IS_ERR(task))
                 init_idle(task, cpu);
@@ -1356,7 +1385,7 @@ 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;
@@ -1387,19 +1416,16 @@ 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.
@@ -1407,6 +1433,17 @@ 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);
@@ -1440,7 +1477,6 @@ long do_fork(unsigned long clone_flags,
                         }
                 }
         } else {
-                free_pid(pid);
                 nr = PTR_ERR(p);
         }
         return nr;
@@ -1485,7 +1521,7 @@ 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
@@ -1617,7 +1653,7 @@ 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);
 
@@ -1647,14 +1683,13 @@ 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;