s390/uaccess: always run the kernel in home space

Simplify the uaccess code by removing the user_mode=home option.
The kernel will now always run in the home space mode.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

4 files changed, 1 insertions, 338 deletions

diff --git a/arch/s390/lib/Makefile b/arch/s390/lib/Makefile
index e506c5fb6f6a..b068729e50ac 100644
--- a/arch/s390/lib/Makefile
+++ b/arch/s390/lib/Makefile
@@ -2,7 +2,7 @@
 # Makefile for s390-specific library files..
 #
 
-lib-y += delay.o string.o uaccess_std.o uaccess_pt.o find.o
+lib-y += delay.o string.o uaccess_pt.o find.o
 obj-$(CONFIG_32BIT) += div64.o qrnnd.o ucmpdi2.o mem32.o
 obj-$(CONFIG_64BIT) += mem64.o
 lib-$(CONFIG_64BIT) += uaccess_mvcos.o
diff --git a/arch/s390/lib/uaccess_mvcos.c b/arch/s390/lib/uaccess_mvcos.c
index 1829742bf479..4b7993bf69b9 100644
--- a/arch/s390/lib/uaccess_mvcos.c
+++ b/arch/s390/lib/uaccess_mvcos.c
@@ -65,13 +65,6 @@ static size_t copy_from_user_mvcos(size_t size, const void __user *ptr, void *x)
 	return size;
 }
 
-static size_t copy_from_user_mvcos_check(size_t size, const void __user *ptr, void *x)
-{
-	if (size <= 256)
-		return copy_from_user_std(size, ptr, x);
-	return copy_from_user_mvcos(size, ptr, x);
-}
-
 static size_t copy_to_user_mvcos(size_t size, void __user *ptr, const void *x)
 {
 	register unsigned long reg0 asm("0") = 0x810000UL;
@@ -101,14 +94,6 @@ static size_t copy_to_user_mvcos(size_t size, void __user *ptr, const void *x)
 	return size;
 }
 
-static size_t copy_to_user_mvcos_check(size_t size, void __user *ptr,
-				       const void *x)
-{
-	if (size <= 256)
-		return copy_to_user_std(size, ptr, x);
-	return copy_to_user_mvcos(size, ptr, x);
-}
-
 static size_t copy_in_user_mvcos(size_t size, void __user *to,
 				 const void __user *from)
 {
@@ -201,23 +186,8 @@ static size_t strncpy_from_user_mvcos(size_t count, const char __user *src,
 }
 
 struct uaccess_ops uaccess_mvcos = {
-	.copy_from_user = copy_from_user_mvcos_check,
-	.copy_from_user_small = copy_from_user_std,
-	.copy_to_user = copy_to_user_mvcos_check,
-	.copy_to_user_small = copy_to_user_std,
-	.copy_in_user = copy_in_user_mvcos,
-	.clear_user = clear_user_mvcos,
-	.strnlen_user = strnlen_user_std,
-	.strncpy_from_user = strncpy_from_user_std,
-	.futex_atomic_op = futex_atomic_op_std,
-	.futex_atomic_cmpxchg = futex_atomic_cmpxchg_std,
-};
-
-struct uaccess_ops uaccess_mvcos_switch = {
 	.copy_from_user = copy_from_user_mvcos,
-	.copy_from_user_small = copy_from_user_mvcos,
 	.copy_to_user = copy_to_user_mvcos,
-	.copy_to_user_small = copy_to_user_mvcos,
 	.copy_in_user = copy_in_user_mvcos,
 	.clear_user = clear_user_mvcos,
 	.strnlen_user = strnlen_user_mvcos,
diff --git a/arch/s390/lib/uaccess_pt.c b/arch/s390/lib/uaccess_pt.c
index 1694d738b175..97e03caf7825 100644
--- a/arch/s390/lib/uaccess_pt.c
+++ b/arch/s390/lib/uaccess_pt.c
@@ -461,9 +461,7 @@ int futex_atomic_cmpxchg_pt(u32 *uval, u32 __user *uaddr,
 
 struct uaccess_ops uaccess_pt = {
 	.copy_from_user		= copy_from_user_pt,
-	.copy_from_user_small	= copy_from_user_pt,
 	.copy_to_user		= copy_to_user_pt,
-	.copy_to_user_small	= copy_to_user_pt,
 	.copy_in_user		= copy_in_user_pt,
 	.clear_user		= clear_user_pt,
 	.strnlen_user		= strnlen_user_pt,
diff --git a/arch/s390/lib/uaccess_std.c b/arch/s390/lib/uaccess_std.c
deleted file mode 100644
index 4a75d475b06a..000000000000
--- a/arch/s390/lib/uaccess_std.c
+++ /dev/null
@@ -1,305 +0,0 @@
-/*
- *  Standard user space access functions based on mvcp/mvcs and doing
- *  interesting things in the secondary space mode.
- *
- *    Copyright IBM Corp. 2006
- *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
- *		 Gerald Schaefer (gerald.schaefer@de.ibm.com)
- */
-
-#include <linux/errno.h>
-#include <linux/mm.h>
-#include <linux/uaccess.h>
-#include <asm/futex.h>
-#include "uaccess.h"
-
-#ifndef CONFIG_64BIT
-#define AHI	"ahi"
-#define ALR	"alr"
-#define CLR	"clr"
-#define LHI	"lhi"
-#define SLR	"slr"
-#else
-#define AHI	"aghi"
-#define ALR	"algr"
-#define CLR	"clgr"
-#define LHI	"lghi"
-#define SLR	"slgr"
-#endif
-
-size_t copy_from_user_std(size_t size, const void __user *ptr, void *x)
-{
-	unsigned long tmp1, tmp2;
-
-	tmp1 = -256UL;
-	asm volatile(
-		"0: mvcp  0(%0,%2),0(%1),%3\n"
-		"10:jz    8f\n"
-		"1:"ALR"  %0,%3\n"
-		"   la    %1,256(%1)\n"
-		"   la    %2,256(%2)\n"
-		"2: mvcp  0(%0,%2),0(%1),%3\n"
-		"11:jnz   1b\n"
-		"   j     8f\n"
-		"3: la    %4,255(%1)\n"	/* %4 = ptr + 255 */
-		"  "LHI"  %3,-4096\n"
-		"   nr    %4,%3\n"	/* %4 = (ptr + 255) & -4096 */
-		"  "SLR"  %4,%1\n"
-		"  "CLR"  %0,%4\n"	/* copy crosses next page boundary? */
-		"   jnh   5f\n"
-		"4: mvcp  0(%4,%2),0(%1),%3\n"
-		"12:"SLR"  %0,%4\n"
-		"  "ALR"  %2,%4\n"
-		"5:"LHI"  %4,-1\n"
-		"  "ALR"  %4,%0\n"	/* copy remaining size, subtract 1 */
-		"   bras  %3,7f\n"	/* memset loop */
-		"   xc    0(1,%2),0(%2)\n"
-		"6: xc    0(256,%2),0(%2)\n"
-		"   la    %2,256(%2)\n"
-		"7:"AHI"  %4,-256\n"
-		"   jnm   6b\n"
-		"   ex    %4,0(%3)\n"
-		"   j     9f\n"
-		"8:"SLR"  %0,%0\n"
-		"9: \n"
-		EX_TABLE(0b,3b) EX_TABLE(2b,3b) EX_TABLE(4b,5b)
-		EX_TABLE(10b,3b) EX_TABLE(11b,3b) EX_TABLE(12b,5b)
-		: "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2)
-		: : "cc", "memory");
-	return size;
-}
-
-static size_t copy_from_user_std_check(size_t size, const void __user *ptr,
-				       void *x)
-{
-	if (size <= 1024)
-		return copy_from_user_std(size, ptr, x);
-	return copy_from_user_pt(size, ptr, x);
-}
-
-size_t copy_to_user_std(size_t size, void __user *ptr, const void *x)
-{
-	unsigned long tmp1, tmp2;
-
-	tmp1 = -256UL;
-	asm volatile(
-		"0: mvcs  0(%0,%1),0(%2),%3\n"
-		"7: jz    5f\n"
-		"1:"ALR"  %0,%3\n"
-		"   la    %1,256(%1)\n"
-		"   la    %2,256(%2)\n"
-		"2: mvcs  0(%0,%1),0(%2),%3\n"
-		"8: jnz   1b\n"
-		"   j     5f\n"
-		"3: la    %4,255(%1)\n" /* %4 = ptr + 255 */
-		"  "LHI"  %3,-4096\n"
-		"   nr    %4,%3\n"	/* %4 = (ptr + 255) & -4096 */
-		"  "SLR"  %4,%1\n"
-		"  "CLR"  %0,%4\n"	/* copy crosses next page boundary? */
-		"   jnh   6f\n"
-		"4: mvcs  0(%4,%1),0(%2),%3\n"
-		"9:"SLR"  %0,%4\n"
-		"   j     6f\n"
-		"5:"SLR"  %0,%0\n"
-		"6: \n"
-		EX_TABLE(0b,3b) EX_TABLE(2b,3b) EX_TABLE(4b,6b)
-		EX_TABLE(7b,3b) EX_TABLE(8b,3b) EX_TABLE(9b,6b)
-		: "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2)
-		: : "cc", "memory");
-	return size;
-}
-
-static size_t copy_to_user_std_check(size_t size, void __user *ptr,
-				     const void *x)
-{
-	if (size <= 1024)
-		return copy_to_user_std(size, ptr, x);
-	return copy_to_user_pt(size, ptr, x);
-}
-
-static size_t copy_in_user_std(size_t size, void __user *to,
-			       const void __user *from)
-{
-	unsigned long tmp1;
-
-	asm volatile(
-		"   sacf  256\n"
-		"  "AHI"  %0,-1\n"
-		"   jo    5f\n"
-		"   bras  %3,3f\n"
-		"0:"AHI"  %0,257\n"
-		"1: mvc   0(1,%1),0(%2)\n"
-		"   la    %1,1(%1)\n"
-		"   la    %2,1(%2)\n"
-		"  "AHI"  %0,-1\n"
-		"   jnz   1b\n"
-		"   j     5f\n"
-		"2: mvc   0(256,%1),0(%2)\n"
-		"   la    %1,256(%1)\n"
-		"   la    %2,256(%2)\n"
-		"3:"AHI"  %0,-256\n"
-		"   jnm   2b\n"
-		"4: ex    %0,1b-0b(%3)\n"
-		"5: "SLR"  %0,%0\n"
-		"6: sacf  0\n"
-		EX_TABLE(1b,6b) EX_TABLE(2b,0b) EX_TABLE(4b,0b)
-		: "+a" (size), "+a" (to), "+a" (from), "=a" (tmp1)
-		: : "cc", "memory");
-	return size;
-}
-
-static size_t clear_user_std(size_t size, void __user *to)
-{
-	unsigned long tmp1, tmp2;
-
-	asm volatile(
-		"   sacf  256\n"
-		"  "AHI"  %0,-1\n"
-		"   jo    5f\n"
-		"   bras  %3,3f\n"
-		"   xc    0(1,%1),0(%1)\n"
-		"0:"AHI"  %0,257\n"
-		"   la    %2,255(%1)\n" /* %2 = ptr + 255 */
-		"   srl   %2,12\n"
-		"   sll   %2,12\n"	/* %2 = (ptr + 255) & -4096 */
-		"  "SLR"  %2,%1\n"
-		"  "CLR"  %0,%2\n"	/* clear crosses next page boundary? */
-		"   jnh   5f\n"
-		"  "AHI"  %2,-1\n"
-		"1: ex    %2,0(%3)\n"
-		"  "AHI"  %2,1\n"
-		"  "SLR"  %0,%2\n"
-		"   j     5f\n"
-		"2: xc    0(256,%1),0(%1)\n"
-		"   la    %1,256(%1)\n"
-		"3:"AHI"  %0,-256\n"
-		"   jnm   2b\n"
-		"4: ex    %0,0(%3)\n"
-		"5: "SLR"  %0,%0\n"
-		"6: sacf  0\n"
-		EX_TABLE(1b,6b) EX_TABLE(2b,0b) EX_TABLE(4b,0b)
-		: "+a" (size), "+a" (to), "=a" (tmp1), "=a" (tmp2)
-		: : "cc", "memory");
-	return size;
-}
-
-size_t strnlen_user_std(size_t size, const char __user *src)
-{
-	register unsigned long reg0 asm("0") = 0UL;
-	unsigned long tmp1, tmp2;
-
-	if (unlikely(!size))
-		return 0;
-	asm volatile(
-		"   la    %2,0(%1)\n"
-		"   la    %3,0(%0,%1)\n"
-		"  "SLR"  %0,%0\n"
-		"   sacf  256\n"
-		"0: srst  %3,%2\n"
-		"   jo    0b\n"
-		"   la    %0,1(%3)\n"	/* strnlen_user results includes \0 */
-		"  "SLR"  %0,%1\n"
-		"1: sacf  0\n"
-		EX_TABLE(0b,1b)
-		: "+a" (size), "+a" (src), "=a" (tmp1), "=a" (tmp2)
-		: "d" (reg0) : "cc", "memory");
-	return size;
-}
-
-size_t strncpy_from_user_std(size_t count, const char __user *src, char *dst)
-{
-	size_t done, len, offset, len_str;
-
-	if (unlikely(!count))
-		return 0;
-	done = 0;
-	do {
-		offset = (size_t)src & ~PAGE_MASK;
-		len = min(count - done, PAGE_SIZE - offset);
-		if (copy_from_user_std(len, src, dst))
-			return -EFAULT;
-		len_str = strnlen(dst, len);
-		done += len_str;
-		src += len_str;
-		dst += len_str;
-	} while ((len_str == len) && (done < count));
-	return done;
-}
-
-#define __futex_atomic_op(insn, ret, oldval, newval, uaddr, oparg)	\
-	asm volatile(							\
-		"   sacf  256\n"					\
-		"0: l     %1,0(%6)\n"					\
-		"1:"insn						\
-		"2: cs    %1,%2,0(%6)\n"				\
-		"3: jl    1b\n"						\
-		"   lhi   %0,0\n"					\
-		"4: sacf  0\n"						\
-		EX_TABLE(0b,4b) EX_TABLE(2b,4b) EX_TABLE(3b,4b)		\
-		: "=d" (ret), "=&d" (oldval), "=&d" (newval),		\
-		  "=m" (*uaddr)						\
-		: "0" (-EFAULT), "d" (oparg), "a" (uaddr),		\
-		  "m" (*uaddr) : "cc");
-
-int futex_atomic_op_std(int op, u32 __user *uaddr, int oparg, int *old)
-{
-	int oldval = 0, newval, ret;
-
-	switch (op) {
-	case FUTEX_OP_SET:
-		__futex_atomic_op("lr %2,%5\n",
-				  ret, oldval, newval, uaddr, oparg);
-		break;
-	case FUTEX_OP_ADD:
-		__futex_atomic_op("lr %2,%1\nar %2,%5\n",
-				  ret, oldval, newval, uaddr, oparg);
-		break;
-	case FUTEX_OP_OR:
-		__futex_atomic_op("lr %2,%1\nor %2,%5\n",
-				  ret, oldval, newval, uaddr, oparg);
-		break;
-	case FUTEX_OP_ANDN:
-		__futex_atomic_op("lr %2,%1\nnr %2,%5\n",
-				  ret, oldval, newval, uaddr, oparg);
-		break;
-	case FUTEX_OP_XOR:
-		__futex_atomic_op("lr %2,%1\nxr %2,%5\n",
-				  ret, oldval, newval, uaddr, oparg);
-		break;
-	default:
-		ret = -ENOSYS;
-	}
-	*old = oldval;
-	return ret;
-}
-
-int futex_atomic_cmpxchg_std(u32 *uval, u32 __user *uaddr,
-			     u32 oldval, u32 newval)
-{
-	int ret;
-
-	asm volatile(
-		"   sacf 256\n"
-		"0: cs   %1,%4,0(%5)\n"
-		"1: la   %0,0\n"
-		"2: sacf 0\n"
-		EX_TABLE(0b,2b) EX_TABLE(1b,2b)
-		: "=d" (ret), "+d" (oldval), "=m" (*uaddr)
-		: "0" (-EFAULT), "d" (newval), "a" (uaddr), "m" (*uaddr)
-		: "cc", "memory" );
-	*uval = oldval;
-	return ret;
-}
-
-struct uaccess_ops uaccess_std = {
-	.copy_from_user = copy_from_user_std_check,
-	.copy_from_user_small = copy_from_user_std,
-	.copy_to_user = copy_to_user_std_check,
-	.copy_to_user_small = copy_to_user_std,
-	.copy_in_user = copy_in_user_std,
-	.clear_user = clear_user_std,
-	.strnlen_user = strnlen_user_std,
-	.strncpy_from_user = strncpy_from_user_std,
-	.futex_atomic_op = futex_atomic_op_std,
-	.futex_atomic_cmpxchg = futex_atomic_cmpxchg_std,
-};