From: Gerald Schaefer <[email protected]>
[S390] Use alternative user-copy operations for new hardware.
This introduces new user-copy operations which are optimized for
copying more than 256 Bytes on new hardware.
Signed-off-by: Gerald Schaefer <[email protected]>
Signed-off-by: Martin Schwidefsky <[email protected]>
---
arch/s390/kernel/head64.S | 13 +++
arch/s390/kernel/setup.c | 6 +
arch/s390/lib/Makefile | 1
arch/s390/lib/uaccess_mvcos.c | 156 ++++++++++++++++++++++++++++++++++++++++++
include/asm-s390/setup.h | 2
include/asm-s390/uaccess.h | 1
6 files changed, 178 insertions(+), 1 deletion(-)
diff -urpN linux-2.6/arch/s390/kernel/head64.S linux-2.6-patched/arch/s390/kernel/head64.S
--- linux-2.6/arch/s390/kernel/head64.S 2006-09-12 10:57:46.000000000 +0200
+++ linux-2.6-patched/arch/s390/kernel/head64.S 2006-09-12 10:57:59.000000000 +0200
@@ -250,6 +250,19 @@ startup_continue:
oi 7(%r12),0x80 # set IDTE flag
0:
+#
+# find out if we have the MVCOS instruction
+#
+ la %r1,0f-.LPG1(%r13) # set program check address
+ stg %r1,__LC_PGM_NEW_PSW+8
+ .short 0xc800 # mvcos 0(%r0),0(%r0),%r0
+ .short 0x0000
+ .short 0x0000
+0: tm 0x8f,0x13 # special-operation exception?
+ bno 1f-.LPG1(%r13) # if yes, MVCOS is present
+ oi 6(%r12),2 # set MVCOS flag
+1:
+
lpswe .Lentry-.LPG1(13) # jump to _stext in primary-space,
# virtual and never return ...
.align 16
diff -urpN linux-2.6/arch/s390/kernel/setup.c linux-2.6-patched/arch/s390/kernel/setup.c
--- linux-2.6/arch/s390/kernel/setup.c 2006-09-12 10:57:59.000000000 +0200
+++ linux-2.6-patched/arch/s390/kernel/setup.c 2006-09-12 10:57:59.000000000 +0200
@@ -647,7 +647,11 @@ setup_arch(char **cmdline_p)
memory_end = memory_size;
- memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
+ if (MACHINE_HAS_MVCOS)
+ memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
+ else
+ memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
+
parse_early_param();
#ifndef CONFIG_64BIT
diff -urpN linux-2.6/arch/s390/lib/Makefile linux-2.6-patched/arch/s390/lib/Makefile
--- linux-2.6/arch/s390/lib/Makefile 2006-09-12 10:57:59.000000000 +0200
+++ linux-2.6-patched/arch/s390/lib/Makefile 2006-09-12 10:57:59.000000000 +0200
@@ -5,4 +5,5 @@
EXTRA_AFLAGS := -traditional
lib-y += delay.o string.o uaccess_std.o
+lib-$(CONFIG_64BIT) += uaccess_mvcos.o
lib-$(CONFIG_SMP) += spinlock.o
diff -urpN linux-2.6/arch/s390/lib/uaccess_mvcos.c linux-2.6-patched/arch/s390/lib/uaccess_mvcos.c
--- linux-2.6/arch/s390/lib/uaccess_mvcos.c 1970-01-01 01:00:00.000000000 +0100
+++ linux-2.6-patched/arch/s390/lib/uaccess_mvcos.c 2006-09-12 10:57:59.000000000 +0200
@@ -0,0 +1,156 @@
+/*
+ * arch/s390/lib/uaccess_mvcos.c
+ *
+ * Optimized user space space access functions based on mvcos.
+ *
+ * Copyright (C) IBM Corp. 2006
+ * Author(s): Martin Schwidefsky ([email protected]),
+ * Gerald Schaefer ([email protected])
+ */
+
+#include <linux/errno.h>
+#include <linux/mm.h>
+#include <asm/uaccess.h>
+#include <asm/futex.h>
+
+#ifndef __s390x__
+#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_mvcos(size_t size, const void __user *ptr, void *x)
+{
+ register unsigned long reg0 asm("0") = 0x81UL;
+ unsigned long tmp1, tmp2;
+
+ tmp1 = -4096UL;
+ asm volatile(
+ "0: .insn ss,0xc80000000000,0(%0,%2),0(%1),0\n"
+ " jz 4f\n"
+ "1:"ALR" %0,%3\n"
+ " "SLR" %1,%3\n"
+ " "SLR" %2,%3\n"
+ " j 0b\n"
+ "2: la %4,4095(%1)\n"/* %4 = ptr + 4095 */
+ " nr %4,%3\n" /* %4 = (ptr + 4095) & -4096 */
+ " "SLR" %4,%1\n"
+ " "CLR" %0,%4\n" /* copy crosses next page boundary? */
+ " jnh 5f\n"
+ "3: .insn ss,0xc80000000000,0(%4,%2),0(%1),0\n"
+ " "SLR" %0,%4\n"
+ " j 5f\n"
+ "4:"SLR" %0,%0\n"
+ "5: \n"
+ EX_TABLE(0b,2b) EX_TABLE(3b,5b)
+ : "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2)
+ : "d" (reg0) : "cc", "memory");
+ return size;
+}
+
+size_t copy_to_user_mvcos(size_t size, void __user *ptr, const void *x)
+{
+ register unsigned long reg0 asm("0") = 0x810000UL;
+ unsigned long tmp1, tmp2;
+
+ tmp1 = -4096UL;
+ asm volatile(
+ "0: .insn ss,0xc80000000000,0(%0,%1),0(%2),0\n"
+ " jz 4f\n"
+ "1:"ALR" %0,%3\n"
+ " "SLR" %1,%3\n"
+ " "SLR" %2,%3\n"
+ " j 0b\n"
+ "2: la %4,4095(%1)\n"/* %4 = ptr + 4095 */
+ " nr %4,%3\n" /* %4 = (ptr + 4095) & -4096 */
+ " "SLR" %4,%1\n"
+ " "CLR" %0,%4\n" /* copy crosses next page boundary? */
+ " jnh 5f\n"
+ "3: .insn ss,0xc80000000000,0(%4,%1),0(%2),0\n"
+ " "SLR" %0,%4\n"
+ " j 5f\n"
+ "4:"SLR" %0,%0\n"
+ "5: \n"
+ EX_TABLE(0b,2b) EX_TABLE(3b,5b)
+ : "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2)
+ : "d" (reg0) : "cc", "memory");
+ return size;
+}
+
+size_t copy_in_user_mvcos(size_t size, void __user *to, const void __user *from)
+{
+ register unsigned long reg0 asm("0") = 0x810081UL;
+ unsigned long tmp1, tmp2;
+
+ tmp1 = -4096UL;
+ /* FIXME: copy with reduced length. */
+ asm volatile(
+ "0: .insn ss,0xc80000000000,0(%0,%1),0(%2),0\n"
+ " jz 2f\n"
+ "1:"ALR" %0,%3\n"
+ " "SLR" %1,%3\n"
+ " "SLR" %2,%3\n"
+ " j 0b\n"
+ "2:"SLR" %0,%0\n"
+ "3: \n"
+ EX_TABLE(0b,3b)
+ : "+a" (size), "+a" (to), "+a" (from), "+a" (tmp1), "=a" (tmp2)
+ : "d" (reg0) : "cc", "memory");
+ return size;
+}
+
+size_t clear_user_mvcos(size_t size, void __user *to)
+{
+ register unsigned long reg0 asm("0") = 0x810000UL;
+ unsigned long tmp1, tmp2;
+
+ tmp1 = -4096UL;
+ asm volatile(
+ "0: .insn ss,0xc80000000000,0(%0,%1),0(%4),0\n"
+ " jz 4f\n"
+ "1:"ALR" %0,%2\n"
+ " "SLR" %1,%2\n"
+ " j 0b\n"
+ "2: la %3,4095(%1)\n"/* %4 = to + 4095 */
+ " nr %3,%2\n" /* %4 = (to + 4095) & -4096 */
+ " "SLR" %3,%1\n"
+ " "CLR" %0,%3\n" /* copy crosses next page boundary? */
+ " jnh 5f\n"
+ "3: .insn ss,0xc80000000000,0(%3,%1),0(%4),0\n"
+ " "SLR" %0,%3\n"
+ " j 5f\n"
+ "4:"SLR" %0,%0\n"
+ "5: \n"
+ EX_TABLE(0b,2b) EX_TABLE(3b,5b)
+ : "+a" (size), "+a" (to), "+a" (tmp1), "=a" (tmp2)
+ : "a" (empty_zero_page), "d" (reg0) : "cc", "memory");
+ return size;
+}
+
+extern size_t copy_from_user_std_small(size_t, const void __user *, void *);
+extern size_t copy_to_user_std_small(size_t, void __user *, const void *);
+extern size_t strnlen_user_std(size_t, const char __user *);
+extern size_t strncpy_from_user_std(size_t, const char __user *, char *);
+extern int futex_atomic_op(int, int __user *, int, int *);
+extern int futex_atomic_cmpxchg(int __user *, int, int);
+
+struct uaccess_ops uaccess_mvcos = {
+ .copy_from_user = copy_from_user_mvcos,
+ .copy_from_user_small = copy_from_user_std_small,
+ .copy_to_user = copy_to_user_mvcos,
+ .copy_to_user_small = copy_to_user_std_small,
+ .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,
+ .futex_atomic_cmpxchg = futex_atomic_cmpxchg,
+};
diff -urpN linux-2.6/include/asm-s390/setup.h linux-2.6-patched/include/asm-s390/setup.h
--- linux-2.6/include/asm-s390/setup.h 2006-09-12 10:57:46.000000000 +0200
+++ linux-2.6-patched/include/asm-s390/setup.h 2006-09-12 10:57:59.000000000 +0200
@@ -44,10 +44,12 @@ extern unsigned long machine_flags;
#define MACHINE_HAS_IEEE (machine_flags & 2)
#define MACHINE_HAS_CSP (machine_flags & 8)
#define MACHINE_HAS_DIAG44 (1)
+#define MACHINE_HAS_MVCOS (0)
#else /* __s390x__ */
#define MACHINE_HAS_IEEE (1)
#define MACHINE_HAS_CSP (1)
#define MACHINE_HAS_DIAG44 (machine_flags & 32)
+#define MACHINE_HAS_MVCOS (machine_flags & 512)
#endif /* __s390x__ */
diff -urpN linux-2.6/include/asm-s390/uaccess.h linux-2.6-patched/include/asm-s390/uaccess.h
--- linux-2.6/include/asm-s390/uaccess.h 2006-09-12 10:57:59.000000000 +0200
+++ linux-2.6-patched/include/asm-s390/uaccess.h 2006-09-12 10:57:59.000000000 +0200
@@ -100,6 +100,7 @@ struct uaccess_ops {
extern struct uaccess_ops uaccess;
extern struct uaccess_ops uaccess_std;
+extern struct uaccess_ops uaccess_mvcos;
static inline int __put_user_fn(size_t size, void __user *ptr, void *x)
{