Patched in Tegra support.

1 files changed, 25 insertions, 16 deletions

diff --git a/fs/ioprio.c b/fs/ioprio.c
index e50170ca7c3..7da2a06508e 100644
--- a/fs/ioprio.c
+++ b/fs/ioprio.c
@@ -21,7 +21,6 @@
  */
 #include <linux/gfp.h>
 #include <linux/kernel.h>
-#include <linux/export.h>
 #include <linux/ioprio.h>
 #include <linux/blkdev.h>
 #include <linux/capability.h>
@@ -37,8 +36,8 @@ int set_task_ioprio(struct task_struct *task, int ioprio)
 
         rcu_read_lock();
         tcred = __task_cred(task);
-        if (!uid_eq(tcred->uid, cred->euid) &&
-            !uid_eq(tcred->uid, cred->uid) && !capable(CAP_SYS_NICE)) {
+        if (tcred->uid != cred->euid &&
+            tcred->uid != cred->uid && !capable(CAP_SYS_NICE)) {
                 rcu_read_unlock();
                 return -EPERM;
         }
@@ -48,12 +47,28 @@ int set_task_ioprio(struct task_struct *task, int ioprio)
         if (err)
                 return err;
 
-        ioc = get_task_io_context(task, GFP_ATOMIC, NUMA_NO_NODE);
-        if (ioc) {
+        task_lock(task);
+        do {
+                ioc = task->io_context;
+                /* see wmb() in current_io_context() */
+                smp_read_barrier_depends();
+                if (ioc)
+                        break;
+
+                ioc = alloc_io_context(GFP_ATOMIC, -1);
+                if (!ioc) {
+                        err = -ENOMEM;
+                        break;
+                }
+                task->io_context = ioc;
+        } while (1);
+
+        if (!err) {
                 ioc->ioprio = ioprio;
-                put_io_context(ioc);
+                ioc->ioprio_changed = 1;
         }
 
+        task_unlock(task);
         return err;
 }
 EXPORT_SYMBOL_GPL(set_task_ioprio);
@@ -65,7 +80,6 @@ SYSCALL_DEFINE3(ioprio_set, int, which, int, who, int, ioprio)
         struct task_struct *p, *g;
         struct user_struct *user;
         struct pid *pgrp;
-        kuid_t uid;
         int ret;
 
         switch (class) {
@@ -111,19 +125,16 @@ SYSCALL_DEFINE3(ioprio_set, int, which, int, who, int, ioprio)
                         } while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
                         break;
                 case IOPRIO_WHO_USER:
-                        uid = make_kuid(current_user_ns(), who);
-                        if (!uid_valid(uid))
-                                break;
                         if (!who)
                                 user = current_user();
                         else
-                                user = find_user(uid);
+                                user = find_user(who);
 
                         if (!user)
                                 break;
 
                         do_each_thread(g, p) {
-                                if (!uid_eq(task_uid(p), uid))
+                                if (__task_cred(p)->uid != who)
                                         continue;
                                 ret = set_task_ioprio(p, ioprio);
                                 if (ret)
@@ -178,7 +189,6 @@ SYSCALL_DEFINE2(ioprio_get, int, which, int, who)
         struct task_struct *g, *p;
         struct user_struct *user;
         struct pid *pgrp;
-        kuid_t uid;
         int ret = -ESRCH;
         int tmpio;
 
@@ -208,17 +218,16 @@ SYSCALL_DEFINE2(ioprio_get, int, which, int, who)
                         } while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
                         break;
                 case IOPRIO_WHO_USER:
-                        uid = make_kuid(current_user_ns(), who);
                         if (!who)
                                 user = current_user();
                         else
-                                user = find_user(uid);
+                                user = find_user(who);
 
                         if (!user)
                                 break;
 
                         do_each_thread(g, p) {
-                                if (!uid_eq(task_uid(p), user->uid))
+                                if (__task_cred(p)->uid != user->uid)
                                         continue;
                                 tmpio = get_task_ioprio(p);
                                 if (tmpio < 0)