From: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Date: Thu, 1 Apr 2021 12:56:35 +0000 (+0200)
Subject: MIPS: uaccess: Added __get/__put_kernel_nofault
X-Git-Tag: accepted/tizen/unified/20230118.172025~7338^2~36
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=08ee3a009f49ac160cf8df0b65aa7dc299c811b2;p=platform%2Fkernel%2Flinux-rpi.git

MIPS: uaccess: Added __get/__put_kernel_nofault

Added __get/__put_kernel_nofault as preparation for removing
get/set_fs.

Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---

diff --git a/arch/mips/include/asm/uaccess.h b/arch/mips/include/asm/uaccess.h
index d273a38..c5cab0b 100644
--- a/arch/mips/include/asm/uaccess.h
+++ b/arch/mips/include/asm/uaccess.h
@@ -355,6 +355,18 @@ do {									\
 	(val) = __gu_tmp.t;						\
 }
 
+#define HAVE_GET_KERNEL_NOFAULT
+
+#define __get_kernel_nofault(dst, src, type, err_label)			\
+do {									\
+	int __gu_err;							\
+									\
+	__get_kernel_common(*((type *)(dst)), sizeof(type),		\
+			    (__force type *)(src));			\
+	if (unlikely(__gu_err))						\
+		goto err_label;						\
+} while (0)
+
 #ifndef CONFIG_EVA
 #define __put_kernel_common(ptr, size) __put_user_common(ptr, size)
 #else
@@ -483,6 +495,18 @@ do {									\
 
 extern void __put_user_unknown(void);
 
+#define __put_kernel_nofault(dst, src, type, err_label)			\
+do {									\
+	type __pu_val;					\
+	int __pu_err = 0;						\
+									\
+	__pu_val = *(__force type *)(src);				\
+	__put_kernel_common(((type *)(dst)), sizeof(type));		\
+	if (unlikely(__pu_err))						\
+		goto err_label;						\
+} while (0)
+
+
 /*
  * We're generating jump to subroutines which will be outside the range of
  * jump instructions
diff --git a/arch/mips/mm/Makefile b/arch/mips/mm/Makefile
index fa1f729..4acc4f3 100644
--- a/arch/mips/mm/Makefile
+++ b/arch/mips/mm/Makefile
@@ -22,6 +22,10 @@ else
 obj-y				+= uasm-mips.o
 endif
 
+ifndef CONFIG_EVA
+obj-y				+= maccess.o
+endif
+
 obj-$(CONFIG_32BIT)		+= ioremap.o pgtable-32.o
 obj-$(CONFIG_64BIT)		+= ioremap64.o pgtable-64.o
 obj-$(CONFIG_HIGHMEM)		+= highmem.o
diff --git a/arch/mips/mm/maccess.c b/arch/mips/mm/maccess.c
new file mode 100644
index 0000000..5817384
--- /dev/null
+++ b/arch/mips/mm/maccess.c
@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/uaccess.h>
+#include <linux/kernel.h>
+
+bool copy_from_kernel_nofault_allowed(const void *unsafe_src, size_t size)
+{
+	/* highest bit set means kernel space */
+	return (unsigned long)unsafe_src >> (BITS_PER_LONG - 1);
+}