Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable

[pandora-kernel.git] / fs / ioprio.c

diff --git a/fs/ioprio.c b/fs/ioprio.c
index 2f7d05c..7da2a06 100644 (file)
--- a/fs/ioprio.c
+++ b/fs/ioprio.c
@@ -103,22 +103,15 @@ SYSCALL_DEFINE3(ioprio_set, int, which, int, who, int, ioprio)
        }
 
        ret = -ESRCH;
-       /*
-        * We want IOPRIO_WHO_PGRP/IOPRIO_WHO_USER to be "atomic",
-        * so we can't use rcu_read_lock(). See re-copy of ->ioprio
-        * in copy_process().
-        */
-       read_lock(&tasklist_lock);
+       rcu_read_lock();
        switch (which) {
                case IOPRIO_WHO_PROCESS:
-                       rcu_read_lock();
                        if (!who)
                                p = current;
                        else
                                p = find_task_by_vpid(who);
                        if (p)
                                ret = set_task_ioprio(p, ioprio);
-                       rcu_read_unlock();
                        break;
                case IOPRIO_WHO_PGRP:
                        if (!who)
@@ -141,12 +134,7 @@ SYSCALL_DEFINE3(ioprio_set, int, which, int, who, int, ioprio)
                                break;
 
                        do_each_thread(g, p) {
-                               int match;
-
-                               rcu_read_lock();
-                               match = __task_cred(p)->uid == who;
-                               rcu_read_unlock();
-                               if (!match)
+                               if (__task_cred(p)->uid != who)
                                        continue;
                                ret = set_task_ioprio(p, ioprio);
                                if (ret)
@@ -160,7 +148,7 @@ free_uid:
                        ret = -EINVAL;
        }
 
-       read_unlock(&tasklist_lock);
+       rcu_read_unlock();
        return ret;
 }
 
@@ -204,17 +192,15 @@ SYSCALL_DEFINE2(ioprio_get, int, which, int, who)
        int ret = -ESRCH;
        int tmpio;
 
-       read_lock(&tasklist_lock);
+       rcu_read_lock();
        switch (which) {
                case IOPRIO_WHO_PROCESS:
-                       rcu_read_lock();
                        if (!who)
                                p = current;
                        else
                                p = find_task_by_vpid(who);
                        if (p)
                                ret = get_task_ioprio(p);
-                       rcu_read_unlock();
                        break;
                case IOPRIO_WHO_PGRP:
                        if (!who)
@@ -241,12 +227,7 @@ SYSCALL_DEFINE2(ioprio_get, int, which, int, who)
                                break;
 
                        do_each_thread(g, p) {
-                               int match;
-
-                               rcu_read_lock();
-                               match = __task_cred(p)->uid == user->uid;
-                               rcu_read_unlock();
-                               if (!match)
+                               if (__task_cred(p)->uid != user->uid)
                                        continue;
                                tmpio = get_task_ioprio(p);
                                if (tmpio < 0)
@@ -264,6 +245,6 @@ SYSCALL_DEFINE2(ioprio_get, int, which, int, who)
                        ret = -EINVAL;
        }
 
-       read_unlock(&tasklist_lock);
+       rcu_read_unlock();
        return ret;
 }