sched_rr_get_interval(): move compat to native, get rid of set_fs()

switch to using timespec64 internally, while we are at it

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/kernel/compat.c b/kernel/compat.c
index a46a4a4..d1cee65 100644 (file)
--- a/kernel/compat.c
+++ b/kernel/compat.c
@@ -562,22 +562,6 @@ COMPAT_SYSCALL_DEFINE4(migrate_pages, compat_pid_t, pid,
 }
 #endif
 
-COMPAT_SYSCALL_DEFINE2(sched_rr_get_interval,
-                      compat_pid_t, pid,
-                      struct compat_timespec __user *, interval)
-{
-       struct timespec t;
-       int ret;
-       mm_segment_t old_fs = get_fs();
-
-       set_fs(KERNEL_DS);
-       ret = sys_sched_rr_get_interval(pid, (struct timespec __user *)&t);
-       set_fs(old_fs);
-       if (compat_put_timespec(&t, interval))
-               return -EFAULT;
-       return ret;
-}
-
 /*
  * Allocate user-space memory for the duration of a single system call,
  * in order to marshall parameters inside a compat thunk.

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 18a6966..e74f0a5 100644 (file)
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -16,6 +16,7 @@
 #include <linux/init_task.h>
 #include <linux/context_tracking.h>
 #include <linux/rcupdate_wait.h>
+#include <linux/compat.h>
 
 #include <linux/blkdev.h>
 #include <linux/kprobes.h>
@@ -5098,13 +5099,11 @@ SYSCALL_DEFINE1(sched_get_priority_min, int, policy)
  * Return: On success, 0 and the timeslice is in @interval. Otherwise,
  * an error code.
  */
-SYSCALL_DEFINE2(sched_rr_get_interval, pid_t, pid,
-               struct timespec __user *, interval)
+static int sched_rr_get_interval(pid_t pid, struct timespec64 *t)
 {
        struct task_struct *p;
        unsigned int time_slice;
        struct rq_flags rf;
-       struct timespec t;
        struct rq *rq;
        int retval;
 
@@ -5128,15 +5127,40 @@ SYSCALL_DEFINE2(sched_rr_get_interval, pid_t, pid,
        task_rq_unlock(rq, p, &rf);
 
        rcu_read_unlock();
-       jiffies_to_timespec(time_slice, &t);
-       retval = copy_to_user(interval, &t, sizeof(t)) ? -EFAULT : 0;
-       return retval;
+       jiffies_to_timespec64(time_slice, t);
+       return 0;
 
 out_unlock:
        rcu_read_unlock();
        return retval;
 }
 
+SYSCALL_DEFINE2(sched_rr_get_interval, pid_t, pid,
+               struct timespec __user *, interval)
+{
+       struct timespec64 t;
+       int retval = sched_rr_get_interval(pid, &t);
+
+       if (retval == 0)
+               retval = put_timespec64(&t, interval);
+
+       return retval;
+}
+
+#ifdef CONFIG_COMPAT
+COMPAT_SYSCALL_DEFINE2(sched_rr_get_interval,
+                      compat_pid_t, pid,
+                      struct compat_timespec __user *, interval)
+{
+       struct timespec64 t;
+       int retval = sched_rr_get_interval(pid, &t);
+
+       if (retval == 0)
+               retval = compat_put_timespec64(&t, interval);
+       return retval;
+}
+#endif
+
 void sched_show_task(struct task_struct *p)
 {
        unsigned long free = 0;