]> nv-tegra.nvidia Code Review - linux-2.6.git/blobdiff - kernel/sys.c
9p: eliminate callback complexity
[linux-2.6.git] / kernel / sys.c
index 2b8e2daa9d953e3242cf2843cdebc088cf40d9b9..0bc8fa3c2288110b49fad4e9eaab2326f52c69f7 100644 (file)
 #ifndef SET_ENDIAN
 # define SET_ENDIAN(a,b)       (-EINVAL)
 #endif
+#ifndef GET_TSC_CTL
+# define GET_TSC_CTL(a)                (-EINVAL)
+#endif
+#ifndef SET_TSC_CTL
+# define SET_TSC_CTL(a)                (-EINVAL)
+#endif
 
 /*
  * this is where the system-wide overflow UID and GID are defined, for
@@ -163,9 +169,9 @@ asmlinkage long sys_setpriority(int which, int who, int niceval)
                                pgrp = find_vpid(who);
                        else
                                pgrp = task_pgrp(current);
-                       do_each_pid_task(pgrp, PIDTYPE_PGID, p) {
+                       do_each_pid_thread(pgrp, PIDTYPE_PGID, p) {
                                error = set_one_prio(p, niceval, error);
-                       } while_each_pid_task(pgrp, PIDTYPE_PGID, p);
+                       } while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
                        break;
                case PRIO_USER:
                        user = current->user;
@@ -223,11 +229,11 @@ asmlinkage long sys_getpriority(int which, int who)
                                pgrp = find_vpid(who);
                        else
                                pgrp = task_pgrp(current);
-                       do_each_pid_task(pgrp, PIDTYPE_PGID, p) {
+                       do_each_pid_thread(pgrp, PIDTYPE_PGID, p) {
                                niceval = 20 - task_nice(p);
                                if (niceval > retval)
                                        retval = niceval;
-                       } while_each_pid_task(pgrp, PIDTYPE_PGID, p);
+                       } while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
                        break;
                case PRIO_USER:
                        user = current->user;
@@ -268,7 +274,7 @@ void emergency_restart(void)
 }
 EXPORT_SYMBOL_GPL(emergency_restart);
 
-static void kernel_restart_prepare(char *cmd)
+void kernel_restart_prepare(char *cmd)
 {
        blocking_notifier_call_chain(&reboot_notifier_list, SYS_RESTART, cmd);
        system_state = SYSTEM_RESTART;
@@ -295,26 +301,6 @@ void kernel_restart(char *cmd)
 }
 EXPORT_SYMBOL_GPL(kernel_restart);
 
-/**
- *     kernel_kexec - reboot the system
- *
- *     Move into place and start executing a preloaded standalone
- *     executable.  If nothing was preloaded return an error.
- */
-static void kernel_kexec(void)
-{
-#ifdef CONFIG_KEXEC
-       struct kimage *image;
-       image = xchg(&kexec_image, NULL);
-       if (!image)
-               return;
-       kernel_restart_prepare(NULL);
-       printk(KERN_EMERG "Starting new kernel\n");
-       machine_shutdown();
-       machine_kexec(image);
-#endif
-}
-
 static void kernel_shutdown_prepare(enum system_states state)
 {
        blocking_notifier_call_chain(&reboot_notifier_list,
@@ -419,10 +405,15 @@ asmlinkage long sys_reboot(int magic1, int magic2, unsigned int cmd, void __user
                kernel_restart(buffer);
                break;
 
+#ifdef CONFIG_KEXEC
        case LINUX_REBOOT_CMD_KEXEC:
-               kernel_kexec();
-               unlock_kernel();
-               return -EINVAL;
+               {
+                       int ret;
+                       ret = kernel_kexec();
+                       unlock_kernel();
+                       return ret;
+               }
+#endif
 
 #ifdef CONFIG_HIBERNATION
        case LINUX_REBOOT_CMD_SW_SUSPEND:
@@ -916,8 +907,8 @@ asmlinkage long sys_setpgid(pid_t pid, pid_t pgid)
 {
        struct task_struct *p;
        struct task_struct *group_leader = current->group_leader;
-       int err = -EINVAL;
-       struct pid_namespace *ns;
+       struct pid *pgrp;
+       int err;
 
        if (!pid)
                pid = task_pid_vnr(group_leader);
@@ -929,12 +920,10 @@ asmlinkage long sys_setpgid(pid_t pid, pid_t pgid)
        /* From this point forward we keep holding onto the tasklist lock
         * so that our parent does not change from under us. -DaveM
         */
-       ns = current->nsproxy->pid_ns;
-
        write_lock_irq(&tasklist_lock);
 
        err = -ESRCH;
-       p = find_task_by_pid_ns(pid, ns);
+       p = find_task_by_vpid(pid);
        if (!p)
                goto out;
 
@@ -942,7 +931,7 @@ asmlinkage long sys_setpgid(pid_t pid, pid_t pgid)
        if (!thread_group_leader(p))
                goto out;
 
-       if (p->real_parent->tgid == group_leader->tgid) {
+       if (same_thread_group(p->real_parent, group_leader)) {
                err = -EPERM;
                if (task_session(p) != task_session(group_leader))
                        goto out;
@@ -959,10 +948,12 @@ asmlinkage long sys_setpgid(pid_t pid, pid_t pgid)
        if (p->signal->leader)
                goto out;
 
+       pgrp = task_pid(p);
        if (pgid != pid) {
                struct task_struct *g;
 
-               g = find_task_by_pid_type_ns(PIDTYPE_PGID, pgid, ns);
+               pgrp = find_vpid(pgid);
+               g = pid_task(pgrp, PIDTYPE_PGID);
                if (!g || task_session(g) != task_session(group_leader))
                        goto out;
        }
@@ -971,13 +962,9 @@ asmlinkage long sys_setpgid(pid_t pid, pid_t pgid)
        if (err)
                goto out;
 
-       if (task_pgrp_nr_ns(p, ns) != pgid) {
-               struct pid *pid;
-
-               detach_pid(p, PIDTYPE_PGID);
-               pid = find_vpid(pgid);
-               attach_pid(p, PIDTYPE_PGID, pid);
-               set_task_pgrp(p, pid_nr(pid));
+       if (task_pgrp(p) != pgrp) {
+               change_pid(p, PIDTYPE_PGID, pgrp);
+               set_task_pgrp(p, pid_nr(pgrp));
        }
 
        err = 0;
@@ -989,94 +976,93 @@ out:
 
 asmlinkage long sys_getpgid(pid_t pid)
 {
+       struct task_struct *p;
+       struct pid *grp;
+       int retval;
+
+       rcu_read_lock();
        if (!pid)
-               return task_pgrp_vnr(current);
+               grp = task_pgrp(current);
        else {
-               int retval;
-               struct task_struct *p;
-               struct pid_namespace *ns;
-
-               ns = current->nsproxy->pid_ns;
-
-               read_lock(&tasklist_lock);
-               p = find_task_by_pid_ns(pid, ns);
                retval = -ESRCH;
-               if (p) {
-                       retval = security_task_getpgid(p);
-                       if (!retval)
-                               retval = task_pgrp_nr_ns(p, ns);
-               }
-               read_unlock(&tasklist_lock);
-               return retval;
+               p = find_task_by_vpid(pid);
+               if (!p)
+                       goto out;
+               grp = task_pgrp(p);
+               if (!grp)
+                       goto out;
+
+               retval = security_task_getpgid(p);
+               if (retval)
+                       goto out;
        }
+       retval = pid_vnr(grp);
+out:
+       rcu_read_unlock();
+       return retval;
 }
 
 #ifdef __ARCH_WANT_SYS_GETPGRP
 
 asmlinkage long sys_getpgrp(void)
 {
-       /* SMP - assuming writes are word atomic this is fine */
-       return task_pgrp_vnr(current);
+       return sys_getpgid(0);
 }
 
 #endif
 
 asmlinkage long sys_getsid(pid_t pid)
 {
+       struct task_struct *p;
+       struct pid *sid;
+       int retval;
+
+       rcu_read_lock();
        if (!pid)
-               return task_session_vnr(current);
+               sid = task_session(current);
        else {
-               int retval;
-               struct task_struct *p;
-               struct pid_namespace *ns;
-
-               ns = current->nsproxy->pid_ns;
-
-               read_lock(&tasklist_lock);
-               p = find_task_by_pid_ns(pid, ns);
                retval = -ESRCH;
-               if (p) {
-                       retval = security_task_getsid(p);
-                       if (!retval)
-                               retval = task_session_nr_ns(p, ns);
-               }
-               read_unlock(&tasklist_lock);
-               return retval;
+               p = find_task_by_vpid(pid);
+               if (!p)
+                       goto out;
+               sid = task_session(p);
+               if (!sid)
+                       goto out;
+
+               retval = security_task_getsid(p);
+               if (retval)
+                       goto out;
        }
+       retval = pid_vnr(sid);
+out:
+       rcu_read_unlock();
+       return retval;
 }
 
 asmlinkage long sys_setsid(void)
 {
        struct task_struct *group_leader = current->group_leader;
-       pid_t session;
+       struct pid *sid = task_pid(group_leader);
+       pid_t session = pid_vnr(sid);
        int err = -EPERM;
 
        write_lock_irq(&tasklist_lock);
-
        /* Fail if I am already a session leader */
        if (group_leader->signal->leader)
                goto out;
 
-       session = group_leader->pid;
        /* Fail if a process group id already exists that equals the
         * proposed session id.
-        *
-        * Don't check if session id == 1 because kernel threads use this
-        * session id and so the check will always fail and make it so
-        * init cannot successfully call setsid.
         */
-       if (session > 1 && find_task_by_pid_type_ns(PIDTYPE_PGID,
-                               session, &init_pid_ns))
+       if (pid_task(sid, PIDTYPE_PGID))
                goto out;
 
        group_leader->signal->leader = 1;
-       __set_special_pids(session, session);
+       __set_special_pids(sid);
 
-       spin_lock(&group_leader->sighand->siglock);
-       group_leader->signal->tty = NULL;
-       spin_unlock(&group_leader->sighand->siglock);
+       proc_clear_tty(group_leader);
 
-       err = task_pgrp_vnr(group_leader);
+       err = session;
 out:
        write_unlock_irq(&tasklist_lock);
        return err;
@@ -1145,16 +1131,16 @@ static int groups_to_user(gid_t __user *grouplist,
     struct group_info *group_info)
 {
        int i;
-       int count = group_info->ngroups;
+       unsigned int count = group_info->ngroups;
 
        for (i = 0; i < group_info->nblocks; i++) {
-               int cp_count = min(NGROUPS_PER_BLOCK, count);
-               int off = i * NGROUPS_PER_BLOCK;
-               int len = cp_count * sizeof(*grouplist);
+               unsigned int cp_count = min(NGROUPS_PER_BLOCK, count);
+               unsigned int len = cp_count * sizeof(*grouplist);
 
-               if (copy_to_user(grouplist+off, group_info->blocks[i], len))
+               if (copy_to_user(grouplist, group_info->blocks[i], len))
                        return -EFAULT;
 
+               grouplist += NGROUPS_PER_BLOCK;
                count -= cp_count;
        }
        return 0;
@@ -1165,16 +1151,16 @@ static int groups_from_user(struct group_info *group_info,
     gid_t __user *grouplist)
 {
        int i;
-       int count = group_info->ngroups;
+       unsigned int count = group_info->ngroups;
 
        for (i = 0; i < group_info->nblocks; i++) {
-               int cp_count = min(NGROUPS_PER_BLOCK, count);
-               int off = i * NGROUPS_PER_BLOCK;
-               int len = cp_count * sizeof(*grouplist);
+               unsigned int cp_count = min(NGROUPS_PER_BLOCK, count);
+               unsigned int len = cp_count * sizeof(*grouplist);
 
-               if (copy_from_user(group_info->blocks[i], grouplist+off, len))
+               if (copy_from_user(group_info->blocks[i], grouplist, len))
                        return -EFAULT;
 
+               grouplist += NGROUPS_PER_BLOCK;
                count -= cp_count;
        }
        return 0;
@@ -1340,8 +1326,6 @@ EXPORT_SYMBOL(in_egroup_p);
 
 DECLARE_RWSEM(uts_sem);
 
-EXPORT_SYMBOL(uts_sem);
-
 asmlinkage long sys_newuname(struct new_utsname __user * name)
 {
        int errno = 0;
@@ -1365,8 +1349,10 @@ asmlinkage long sys_sethostname(char __user *name, int len)
        down_write(&uts_sem);
        errno = -EFAULT;
        if (!copy_from_user(tmp, name, len)) {
-               memcpy(utsname()->nodename, tmp, len);
-               utsname()->nodename[len] = 0;
+               struct new_utsname *u = utsname();
+
+               memcpy(u->nodename, tmp, len);
+               memset(u->nodename + len, 0, sizeof(u->nodename) - len);
                errno = 0;
        }
        up_write(&uts_sem);
@@ -1378,15 +1364,17 @@ asmlinkage long sys_sethostname(char __user *name, int len)
 asmlinkage long sys_gethostname(char __user *name, int len)
 {
        int i, errno;
+       struct new_utsname *u;
 
        if (len < 0)
                return -EINVAL;
        down_read(&uts_sem);
-       i = 1 + strlen(utsname()->nodename);
+       u = utsname();
+       i = 1 + strlen(u->nodename);
        if (i > len)
                i = len;
        errno = 0;
-       if (copy_to_user(name, utsname()->nodename, i))
+       if (copy_to_user(name, u->nodename, i))
                errno = -EFAULT;
        up_read(&uts_sem);
        return errno;
@@ -1411,8 +1399,10 @@ asmlinkage long sys_setdomainname(char __user *name, int len)
        down_write(&uts_sem);
        errno = -EFAULT;
        if (!copy_from_user(tmp, name, len)) {
-               memcpy(utsname()->domainname, tmp, len);
-               utsname()->domainname[len] = 0;
+               struct new_utsname *u = utsname();
+
+               memcpy(u->domainname, tmp, len);
+               memset(u->domainname + len, 0, sizeof(u->domainname) - len);
                errno = 0;
        }
        up_write(&uts_sem);
@@ -1466,14 +1456,22 @@ asmlinkage long sys_setrlimit(unsigned int resource, struct rlimit __user *rlim)
                return -EINVAL;
        if (copy_from_user(&new_rlim, rlim, sizeof(*rlim)))
                return -EFAULT;
-       if (new_rlim.rlim_cur > new_rlim.rlim_max)
-               return -EINVAL;
        old_rlim = current->signal->rlim + resource;
        if ((new_rlim.rlim_max > old_rlim->rlim_max) &&
            !capable(CAP_SYS_RESOURCE))
                return -EPERM;
-       if (resource == RLIMIT_NOFILE && new_rlim.rlim_max > sysctl_nr_open)
-               return -EPERM;
+
+       if (resource == RLIMIT_NOFILE) {
+               if (new_rlim.rlim_max == RLIM_INFINITY)
+                       new_rlim.rlim_max = sysctl_nr_open;
+               if (new_rlim.rlim_cur == RLIM_INFINITY)
+                       new_rlim.rlim_cur = sysctl_nr_open;
+               if (new_rlim.rlim_max > sysctl_nr_open)
+                       return -EPERM;
+       }
+
+       if (new_rlim.rlim_cur > new_rlim.rlim_max)
+               return -EINVAL;
 
        retval = security_task_setrlimit(resource, &new_rlim);
        if (retval)
@@ -1554,6 +1552,19 @@ out:
  *
  */
 
+static void accumulate_thread_rusage(struct task_struct *t, struct rusage *r,
+                                    cputime_t *utimep, cputime_t *stimep)
+{
+       *utimep = cputime_add(*utimep, t->utime);
+       *stimep = cputime_add(*stimep, t->stime);
+       r->ru_nvcsw += t->nvcsw;
+       r->ru_nivcsw += t->nivcsw;
+       r->ru_minflt += t->min_flt;
+       r->ru_majflt += t->maj_flt;
+       r->ru_inblock += task_io_get_inblock(t);
+       r->ru_oublock += task_io_get_oublock(t);
+}
+
 static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
 {
        struct task_struct *t;
@@ -1563,12 +1574,14 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
        memset((char *) r, 0, sizeof *r);
        utime = stime = cputime_zero;
 
-       rcu_read_lock();
-       if (!lock_task_sighand(p, &flags)) {
-               rcu_read_unlock();
-               return;
+       if (who == RUSAGE_THREAD) {
+               accumulate_thread_rusage(p, r, &utime, &stime);
+               goto out;
        }
 
+       if (!lock_task_sighand(p, &flags))
+               return;
+
        switch (who) {
                case RUSAGE_BOTH:
                case RUSAGE_CHILDREN:
@@ -1595,14 +1608,7 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
                        r->ru_oublock += p->signal->oublock;
                        t = p;
                        do {
-                               utime = cputime_add(utime, t->utime);
-                               stime = cputime_add(stime, t->stime);
-                               r->ru_nvcsw += t->nvcsw;
-                               r->ru_nivcsw += t->nivcsw;
-                               r->ru_minflt += t->min_flt;
-                               r->ru_majflt += t->maj_flt;
-                               r->ru_inblock += task_io_get_inblock(t);
-                               r->ru_oublock += task_io_get_oublock(t);
+                               accumulate_thread_rusage(t, r, &utime, &stime);
                                t = next_thread(t);
                        } while (t != p);
                        break;
@@ -1610,10 +1616,9 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
                default:
                        BUG();
        }
-
        unlock_task_sighand(p, &flags);
-       rcu_read_unlock();
 
+out:
        cputime_to_timeval(utime, &r->ru_utime);
        cputime_to_timeval(stime, &r->ru_stime);
 }
@@ -1627,7 +1632,8 @@ int getrusage(struct task_struct *p, int who, struct rusage __user *ru)
 
 asmlinkage long sys_getrusage(int who, struct rusage __user *ru)
 {
-       if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN)
+       if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN &&
+           who != RUSAGE_THREAD)
                return -EINVAL;
        return getrusage(current, who, ru);
 }
@@ -1641,10 +1647,9 @@ asmlinkage long sys_umask(int mask)
 asmlinkage long sys_prctl(int option, unsigned long arg2, unsigned long arg3,
                          unsigned long arg4, unsigned long arg5)
 {
-       long error;
+       long error = 0;
 
-       error = security_task_prctl(option, arg2, arg3, arg4, arg5);
-       if (error)
+       if (security_task_prctl(option, arg2, arg3, arg4, arg5, &error))
                return error;
 
        switch (option) {
@@ -1691,23 +1696,10 @@ asmlinkage long sys_prctl(int option, unsigned long arg2, unsigned long arg3,
                        error = PR_TIMING_STATISTICAL;
                        break;
                case PR_SET_TIMING:
-                       if (arg2 == PR_TIMING_STATISTICAL)
-                               error = 0;
-                       else
+                       if (arg2 != PR_TIMING_STATISTICAL)
                                error = -EINVAL;
                        break;
 
-               case PR_GET_KEEPCAPS:
-                       if (current->keep_capabilities)
-                               error = 1;
-                       break;
-               case PR_SET_KEEPCAPS:
-                       if (arg2 != 0 && arg2 != 1) {
-                               error = -EINVAL;
-                               break;
-                       }
-                       current->keep_capabilities = arg2;
-                       break;
                case PR_SET_NAME: {
                        struct task_struct *me = current;
                        unsigned char ncomm[sizeof(me->comm)];
@@ -1741,18 +1733,12 @@ asmlinkage long sys_prctl(int option, unsigned long arg2, unsigned long arg3,
                case PR_SET_SECCOMP:
                        error = prctl_set_seccomp(arg2);
                        break;
-
-               case PR_CAPBSET_READ:
-                       if (!cap_valid(arg2))
-                               return -EINVAL;
-                       return !!cap_raised(current->cap_bset, arg2);
-               case PR_CAPBSET_DROP:
-#ifdef CONFIG_SECURITY_FILE_CAPABILITIES
-                       return cap_prctl_drop(arg2);
-#else
-                       return -EINVAL;
-#endif
-
+               case PR_GET_TSC:
+                       error = GET_TSC_CTL(arg2);
+                       break;
+               case PR_SET_TSC:
+                       error = SET_TSC_CTL(arg2);
+                       break;
                default:
                        error = -EINVAL;
                        break;
@@ -1804,7 +1790,7 @@ int orderly_poweroff(bool force)
                goto out;
        }
 
-       info = call_usermodehelper_setup(argv[0], argv, envp);
+       info = call_usermodehelper_setup(argv[0], argv, envp, GFP_ATOMIC);
        if (info == NULL) {
                argv_free(argv);
                goto out;