summaryrefslogtreecommitdiffstats
path: root/kernel/sys.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/sys.c')
-rw-r--r--kernel/sys.c31
1 files changed, 31 insertions, 0 deletions
diff --git a/kernel/sys.c b/kernel/sys.c
index e236f98f7ec..3f894775488 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -28,6 +28,7 @@
#include <linux/tty.h>
#include <linux/signal.h>
#include <linux/cn_proc.h>
+#include <linux/getcpu.h>
#include <linux/compat.h>
#include <linux/syscalls.h>
@@ -2062,3 +2063,33 @@ asmlinkage long sys_prctl(int option, unsigned long arg2, unsigned long arg3,
}
return error;
}
+
+asmlinkage long sys_getcpu(unsigned __user *cpup, unsigned __user *nodep,
+ struct getcpu_cache __user *cache)
+{
+ int err = 0;
+ int cpu = raw_smp_processor_id();
+ if (cpup)
+ err |= put_user(cpu, cpup);
+ if (nodep)
+ err |= put_user(cpu_to_node(cpu), nodep);
+ if (cache) {
+ /*
+ * The cache is not needed for this implementation,
+ * but make sure user programs pass something
+ * valid. vsyscall implementations can instead make
+ * good use of the cache. Only use t0 and t1 because
+ * these are available in both 32bit and 64bit ABI (no
+ * need for a compat_getcpu). 32bit has enough
+ * padding
+ */
+ unsigned long t0, t1;
+ get_user(t0, &cache->t0);
+ get_user(t1, &cache->t1);
+ t0++;
+ t1++;
+ put_user(t0, &cache->t0);
+ put_user(t1, &cache->t1);
+ }
+ return err ? -EFAULT : 0;
+}