maccess,probe_kernel: Allow arch specific override probe_kernel_(read|write)

Some archs such as blackfin, would like to have an arch specific
probe_kernel_read() and probe_kernel_write() implementation which can
fall back to the generic implementation if no special operations are
needed.

CC: Thomas Gleixner <tglx@linutronix.de>
CC: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
diff --git a/include/linux/uaccess.h b/include/linux/uaccess.h
index 6b58367..d512d98 100644
--- a/include/linux/uaccess.h
+++ b/include/linux/uaccess.h
@@ -94,6 +94,7 @@
  * happens, handle that and return -EFAULT.
  */
 extern long probe_kernel_read(void *dst, void *src, size_t size);
+extern long __probe_kernel_read(void *dst, void *src, size_t size);
 
 /*
  * probe_kernel_write(): safely attempt to write to a location
@@ -104,6 +105,7 @@
  * Safely write to address @dst from the buffer at @src.  If a kernel fault
  * happens, handle that and return -EFAULT.
  */
-extern long probe_kernel_write(void *dst, void *src, size_t size);
+extern long notrace probe_kernel_write(void *dst, void *src, size_t size);
+extern long notrace __probe_kernel_write(void *dst, void *src, size_t size);
 
 #endif		/* __LINUX_UACCESS_H__ */