MIPS: lib: strncpy_user: Add EVA support

In non-EVA mode, strncpy_from_user* aliases are used for the
strncpy_from_kernel* symbols since the code is identical. In EVA
mode, new strcpy_from_user* symbols are used which use the EVA
specific instructions to load values from userspace.
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>

arch/mips/kernel/mips_ksyms.c

@@ -16,6 +16,10 @@
 #include <asm/ftrace.h>
 
 extern void *__bzero(void *__s, size_t __count);
+extern long __strncpy_from_kernel_nocheck_asm(char *__to,
+					      const char *__from, long __len);
+extern long __strncpy_from_kernel_asm(char *__to, const char *__from,
+				      long __len);
 extern long __strncpy_from_user_nocheck_asm(char *__to,
 					    const char *__from, long __len);
 extern long __strncpy_from_user_asm(char *__to, const char *__from,
@@ -48,6 +52,8 @@ EXPORT_SYMBOL(copy_page);
 EXPORT_SYMBOL(__copy_user);
 EXPORT_SYMBOL(__copy_user_inatomic);
 EXPORT_SYMBOL(__bzero);
+EXPORT_SYMBOL(__strncpy_from_kernel_nocheck_asm);
+EXPORT_SYMBOL(__strncpy_from_kernel_asm);
 EXPORT_SYMBOL(__strncpy_from_user_nocheck_asm);
 EXPORT_SYMBOL(__strncpy_from_user_asm);
 EXPORT_SYMBOL(__strlen_kernel_nocheck_asm);

arch/mips/lib/strncpy_user.S

@@ -38,7 +38,11 @@ FEXPORT(__strncpy_from_\func\()_nocheck_asm)
 	.set		noreorder
 	move		t0, zero
 	move		v1, a1
+.ifeqs "\func","kernel"
 1:	EX(lbu, v0, (v1), .Lfault\@)
+.else
+1:	EX(lbue, v0, (v1), .Lfault\@)
+.endif
 	PTR_ADDIU	v1, 1
 	R10KCBARRIER(0(ra))
 	beqz		v0, 2f
@@ -63,4 +67,19 @@ FEXPORT(__strncpy_from_\func\()_nocheck_asm)
 
 	.endm
 
+#ifndef CONFIG_EVA
+	/* Set aliases */
+	.global __strncpy_from_user_asm
+	.global __strncpy_from_user_nocheck_asm
+	.set __strncpy_from_user_asm, __strncpy_from_kernel_asm
+	.set __strncpy_from_user_nocheck_asm, __strncpy_from_kernel_nocheck_asm
+#endif
+
+__BUILD_STRNCPY_ASM kernel
+
+#ifdef CONFIG_EVA
+	.set push
+	.set eva
 __BUILD_STRNCPY_ASM user
+	.set pop
+#endif