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* [patch 0/2] vdso support for s390
@ 2008-10-15 17:45 Martin Schwidefsky
  2008-10-15 17:45 ` [patch 1/2] arch_setup_additional_pages arguments Martin Schwidefsky
  2008-10-15 17:45 ` [patch 2/2] introduce vdso on s390 Martin Schwidefsky
  0 siblings, 2 replies; 5+ messages in thread
From: Martin Schwidefsky @ 2008-10-15 17:45 UTC (permalink / raw)
  To: linux-kernel, linux-s390, linux-arch; +Cc: Heiko Carstens

Greetings,
the two patches in this series add a vdso to s390 for three system calls:
1) gettimeofday
2) clock_getres for CLOCK_REALTIME and CLOCK_MONOTONIC
3) clock_gettime for CLOCK_REALTIME and CLOCK_MONOTONIC
The vdso code for gettimeofday is about 4-5 times faster than the system
call. Similar results for clock_gettime.

The first of the two patches changes the arch_setup_additional_pages
function. The second argument is unused and can be removed. For the
s390 vdso I want to know if the elf executable is dynamically linked
or not. Only if an interpreter is used the vdso is mapped. This adds
a second argument to arch_setup_additional_pages again but with a
different semantic.

-- 
blue skies,
   Martin.

"Reality continues to ruin my life." - Calvin.


^ permalink raw reply	[flat|nested] 5+ messages in thread

* [patch 1/2] arch_setup_additional_pages arguments
  2008-10-15 17:45 [patch 0/2] vdso support for s390 Martin Schwidefsky
@ 2008-10-15 17:45 ` Martin Schwidefsky
  2008-10-15 17:45 ` [patch 2/2] introduce vdso on s390 Martin Schwidefsky
  1 sibling, 0 replies; 5+ messages in thread
From: Martin Schwidefsky @ 2008-10-15 17:45 UTC (permalink / raw)
  To: linux-kernel, linux-s390, linux-arch; +Cc: Heiko Carstens, Martin Schwidefsky

[-- Attachment #1: 100-vdso-dynobj.diff --]
[-- Type: text/plain, Size: 5486 bytes --]

From: Martin Schwidefsky <schwidefsky@de.ibm.com>

arch_setup_additional_pages currently gets two arguments, the binary
format descripton and an indication if the process uses an executable
stack or not. The second argument is not used by anybody, it could
be removed without replacement.

What actually does make sense is to pass an indication if the process
uses the elf interpreter or not. The glibc code will not use anything
from the vdso if the process does not use the dynamic linker, so for
statically linked binaries the architecture backend can choose not
to map the vdso.

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

 arch/powerpc/include/asm/elf.h     |    2 +-
 arch/powerpc/kernel/vdso.c         |    3 +--
 arch/sh/include/asm/elf.h          |    2 +-
 arch/sh/kernel/vsyscall/vsyscall.c |    3 +--
 arch/x86/vdso/vdso32-setup.c       |    2 +-
 arch/x86/vdso/vma.c                |    2 +-
 fs/binfmt_elf.c                    |    2 +-
 include/asm-x86/elf.h              |    2 +-
 8 files changed, 8 insertions(+), 10 deletions(-)

Index: quilt-2.6/arch/powerpc/include/asm/elf.h
===================================================================
--- quilt-2.6.orig/arch/powerpc/include/asm/elf.h
+++ quilt-2.6/arch/powerpc/include/asm/elf.h
@@ -267,7 +267,7 @@ extern int ucache_bsize;
 #define ARCH_HAS_SETUP_ADDITIONAL_PAGES
 struct linux_binprm;
 extern int arch_setup_additional_pages(struct linux_binprm *bprm,
-				       int executable_stack);
+				       int uses_interp);
 #define VDSO_AUX_ENT(a,b) NEW_AUX_ENT(a,b);
 
 #endif /* __KERNEL__ */
Index: quilt-2.6/arch/powerpc/kernel/vdso.c
===================================================================
--- quilt-2.6.orig/arch/powerpc/kernel/vdso.c
+++ quilt-2.6/arch/powerpc/kernel/vdso.c
@@ -184,8 +184,7 @@ static void dump_vdso_pages(struct vm_ar
  * This is called from binfmt_elf, we create the special vma for the
  * vDSO and insert it into the mm struct tree
  */
-int arch_setup_additional_pages(struct linux_binprm *bprm,
-				int executable_stack)
+int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 {
 	struct mm_struct *mm = current->mm;
 	struct page **vdso_pagelist;
Index: quilt-2.6/arch/sh/include/asm/elf.h
===================================================================
--- quilt-2.6.orig/arch/sh/include/asm/elf.h
+++ quilt-2.6/arch/sh/include/asm/elf.h
@@ -202,7 +202,7 @@ extern int dump_task_fpu (struct task_st
 #define ARCH_HAS_SETUP_ADDITIONAL_PAGES
 struct linux_binprm;
 extern int arch_setup_additional_pages(struct linux_binprm *bprm,
-				       int executable_stack);
+				       int uses_interp);
 
 extern unsigned int vdso_enabled;
 extern void __kernel_vsyscall;
Index: quilt-2.6/arch/sh/kernel/vsyscall/vsyscall.c
===================================================================
--- quilt-2.6.orig/arch/sh/kernel/vsyscall/vsyscall.c
+++ quilt-2.6/arch/sh/kernel/vsyscall/vsyscall.c
@@ -59,8 +59,7 @@ int __init vsyscall_init(void)
 }
 
 /* Setup a VMA at program startup for the vsyscall page */
-int arch_setup_additional_pages(struct linux_binprm *bprm,
-				int executable_stack)
+int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 {
 	struct mm_struct *mm = current->mm;
 	unsigned long addr;
Index: quilt-2.6/arch/x86/vdso/vdso32-setup.c
===================================================================
--- quilt-2.6.orig/arch/x86/vdso/vdso32-setup.c
+++ quilt-2.6/arch/x86/vdso/vdso32-setup.c
@@ -310,7 +310,7 @@ int __init sysenter_setup(void)
 }
 
 /* Setup a VMA at program startup for the vsyscall page */
-int arch_setup_additional_pages(struct linux_binprm *bprm, int exstack)
+int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 {
 	struct mm_struct *mm = current->mm;
 	unsigned long addr;
Index: quilt-2.6/arch/x86/vdso/vma.c
===================================================================
--- quilt-2.6.orig/arch/x86/vdso/vma.c
+++ quilt-2.6/arch/x86/vdso/vma.c
@@ -98,7 +98,7 @@ static unsigned long vdso_addr(unsigned 
 
 /* Setup a VMA at program startup for the vsyscall page.
    Not called for compat tasks */
-int arch_setup_additional_pages(struct linux_binprm *bprm, int exstack)
+int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 {
 	struct mm_struct *mm = current->mm;
 	unsigned long addr;
Index: quilt-2.6/fs/binfmt_elf.c
===================================================================
--- quilt-2.6.orig/fs/binfmt_elf.c
+++ quilt-2.6/fs/binfmt_elf.c
@@ -949,7 +949,7 @@ static int load_elf_binary(struct linux_
 	set_binfmt(&elf_format);
 
 #ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES
-	retval = arch_setup_additional_pages(bprm, executable_stack);
+	retval = arch_setup_additional_pages(bprm, !!elf_interpreter);
 	if (retval < 0) {
 		send_sig(SIGKILL, current, 0);
 		goto out;
Index: quilt-2.6/include/asm-x86/elf.h
===================================================================
--- quilt-2.6.orig/include/asm-x86/elf.h
+++ quilt-2.6/include/asm-x86/elf.h
@@ -325,7 +325,7 @@ struct linux_binprm;
 
 #define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1
 extern int arch_setup_additional_pages(struct linux_binprm *bprm,
-				       int executable_stack);
+				       int uses_interp);
 
 extern int syscall32_setup_pages(struct linux_binprm *, int exstack);
 #define compat_arch_setup_additional_pages	syscall32_setup_pages

-- 
blue skies,
   Martin.

"Reality continues to ruin my life." - Calvin.


^ permalink raw reply	[flat|nested] 5+ messages in thread

* [patch 2/2] introduce vdso on s390
  2008-10-15 17:45 [patch 0/2] vdso support for s390 Martin Schwidefsky
  2008-10-15 17:45 ` [patch 1/2] arch_setup_additional_pages arguments Martin Schwidefsky
@ 2008-10-15 17:45 ` Martin Schwidefsky
  2008-10-17 15:34   ` Bastian Blank
  1 sibling, 1 reply; 5+ messages in thread
From: Martin Schwidefsky @ 2008-10-15 17:45 UTC (permalink / raw)
  To: linux-kernel, linux-s390, linux-arch; +Cc: Heiko Carstens, Martin Schwidefsky

[-- Attachment #1: 101-vdso-s390.diff --]
[-- Type: text/plain, Size: 41291 bytes --]

From: Martin Schwidefsky <schwidefsky@de.ibm.com>

Add a vdso to speed up gettimeofday and clock_getres/clock_gettime for
CLOCK_REALTIME/CLOCK_MONOTONIC.

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

 arch/s390/Kconfig                        |    3 
 arch/s390/include/asm/auxvec.h           |    2 
 arch/s390/include/asm/elf.h              |   16 ++
 arch/s390/include/asm/mmu.h              |    1 
 arch/s390/include/asm/page.h             |    2 
 arch/s390/include/asm/vdso.h             |   39 +++++
 arch/s390/kernel/Makefile                |    9 -
 arch/s390/kernel/asm-offsets.c           |   15 ++
 arch/s390/kernel/time.c                  |   31 ++++
 arch/s390/kernel/vdso.c                  |  232 +++++++++++++++++++++++++++++++
 arch/s390/kernel/vdso32/Makefile         |   55 +++++++
 arch/s390/kernel/vdso32/clock_getres.S   |   39 +++++
 arch/s390/kernel/vdso32/clock_gettime.S  |  128 +++++++++++++++++
 arch/s390/kernel/vdso32/gettimeofday.S   |   82 ++++++++++
 arch/s390/kernel/vdso32/note.S           |   12 +
 arch/s390/kernel/vdso32/vdso32.lds.S     |  138 ++++++++++++++++++
 arch/s390/kernel/vdso32/vdso32_wrapper.S |   13 +
 arch/s390/kernel/vdso64/Makefile         |   55 +++++++
 arch/s390/kernel/vdso64/clock_getres.S   |   39 +++++
 arch/s390/kernel/vdso64/clock_gettime.S  |   89 +++++++++++
 arch/s390/kernel/vdso64/gettimeofday.S   |   56 +++++++
 arch/s390/kernel/vdso64/note.S           |   12 +
 arch/s390/kernel/vdso64/vdso64.lds.S     |  138 ++++++++++++++++++
 arch/s390/kernel/vdso64/vdso64_wrapper.S |   13 +
 24 files changed, 1217 insertions(+), 2 deletions(-)

Index: quilt-2.6/arch/s390/include/asm/auxvec.h
===================================================================
--- quilt-2.6.orig/arch/s390/include/asm/auxvec.h
+++ quilt-2.6/arch/s390/include/asm/auxvec.h
@@ -1,4 +1,6 @@
 #ifndef __ASMS390_AUXVEC_H
 #define __ASMS390_AUXVEC_H
 
+#define AT_SYSINFO_EHDR		33
+
 #endif
Index: quilt-2.6/arch/s390/include/asm/elf.h
===================================================================
--- quilt-2.6.orig/arch/s390/include/asm/elf.h
+++ quilt-2.6/arch/s390/include/asm/elf.h
@@ -120,6 +120,10 @@ typedef s390_compat_regs compat_elf_greg
 #include <asm/system.h>		/* for save_access_regs */
 #include <asm/mmu_context.h>
 
+#include <asm/vdso.h>
+
+extern unsigned int vdso_enabled;
+
 /*
  * This is used to ensure we don't load something for the wrong architecture.
  */
@@ -193,4 +197,16 @@ do {							\
 	current->mm->context.noexec == 0;		\
 })
 
+#define ARCH_DLINFO							    \
+do {									    \
+	if (vdso_enabled)						    \
+		NEW_AUX_ENT(AT_SYSINFO_EHDR,				    \
+			    (unsigned long)current->mm->context.vdso_base); \
+} while (0)
+
+struct linux_binprm;
+
+#define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1
+int arch_setup_additional_pages(struct linux_binprm *, int);
+
 #endif
Index: quilt-2.6/arch/s390/include/asm/mmu.h
===================================================================
--- quilt-2.6.orig/arch/s390/include/asm/mmu.h
+++ quilt-2.6/arch/s390/include/asm/mmu.h
@@ -6,6 +6,7 @@ typedef struct {
 	struct list_head pgtable_list;
 	unsigned long asce_bits;
 	unsigned long asce_limit;
+	unsigned long vdso_base;
 	int noexec;
 	int has_pgste;	 /* The mmu context has extended page tables */
 	int alloc_pgste; /* cloned contexts will have extended page tables */
Index: quilt-2.6/arch/s390/include/asm/page.h
===================================================================
--- quilt-2.6.orig/arch/s390/include/asm/page.h
+++ quilt-2.6/arch/s390/include/asm/page.h
@@ -152,4 +152,6 @@ void arch_alloc_page(struct page *page, 
 #include <asm-generic/memory_model.h>
 #include <asm-generic/page.h>
 
+#define __HAVE_ARCH_GATE_AREA 1
+
 #endif /* _S390_PAGE_H */
Index: quilt-2.6/arch/s390/include/asm/vdso.h
===================================================================
--- /dev/null
+++ quilt-2.6/arch/s390/include/asm/vdso.h
@@ -0,0 +1,39 @@
+#ifndef __S390_VDSO_H__
+#define __S390_VDSO_H__
+
+#ifdef __KERNEL__
+
+/* Default link addresses for the vDSOs */
+#define VDSO32_LBASE	0
+#define VDSO64_LBASE	0
+
+#define VDSO_VERSION_STRING	LINUX_2.6.26
+
+#ifndef __ASSEMBLY__
+
+/*
+ * Note about this structure:
+ *
+ * NEVER USE THIS IN USERSPACE CODE DIRECTLY. The layout of this
+ * structure is supposed to be known only to the function in the vdso
+ * itself and may change without notice.
+ */
+
+struct vdso_data {
+	__u64 tb_update_count;		/* Timebase atomicity ctr	0x00 */
+	__u64 xtime_tod_stamp;		/* TOD clock for xtime		0x08 */
+	__u64 xtime_clock_sec;		/* Kernel time			0x10 */
+	__u64 xtime_clock_nsec;		/*				0x18 */
+	__u64 wtom_clock_sec;		/* Wall to monotonic clock	0x20 */
+	__u64 wtom_clock_nsec;		/*				0x28 */
+	__u32 tz_minuteswest;		/* Minutes west of Greenwich	0x30 */
+	__u32 tz_dsttime;		/* Type of dst correction	0x34 */
+};
+
+extern struct vdso_data *vdso_data;
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* __KERNEL__ */
+
+#endif /* __S390_VDSO_H__ */
Index: quilt-2.6/arch/s390/Kconfig
===================================================================
--- quilt-2.6.orig/arch/s390/Kconfig
+++ quilt-2.6/arch/s390/Kconfig
@@ -43,6 +43,9 @@ config GENERIC_HWEIGHT
 config GENERIC_TIME
 	def_bool y
 
+config GENERIC_TIME_VSYSCALL
+	def_bool y
+
 config GENERIC_CLOCKEVENTS
 	def_bool y
 
Index: quilt-2.6/arch/s390/kernel/asm-offsets.c
===================================================================
--- quilt-2.6.orig/arch/s390/kernel/asm-offsets.c
+++ quilt-2.6/arch/s390/kernel/asm-offsets.c
@@ -6,6 +6,7 @@
 
 #include <linux/sched.h>
 #include <linux/kbuild.h>
+#include <asm/vdso.h>
 
 int main(void)
 {
@@ -38,5 +39,19 @@ int main(void)
 	DEFINE(__SF_BACKCHAIN, offsetof(struct stack_frame, back_chain));
 	DEFINE(__SF_GPRS, offsetof(struct stack_frame, gprs));
 	DEFINE(__SF_EMPTY, offsetof(struct stack_frame, empty1));
+	BLANK();
+	/* timeval/timezone offsets for use by vdso */
+	DEFINE(__VDSO_UPD_COUNT, offsetof(struct vdso_data, tb_update_count));
+	DEFINE(__VDSO_XTIME_STAMP, offsetof(struct vdso_data, xtime_tod_stamp));
+	DEFINE(__VDSO_XTIME_SEC, offsetof(struct vdso_data, xtime_clock_sec));
+	DEFINE(__VDSO_XTIME_NSEC, offsetof(struct vdso_data, xtime_clock_nsec));
+	DEFINE(__VDSO_WTOM_SEC, offsetof(struct vdso_data, wtom_clock_sec));
+	DEFINE(__VDSO_WTOM_NSEC, offsetof(struct vdso_data, wtom_clock_nsec));
+	DEFINE(__VDSO_TIMEZONE, offsetof(struct vdso_data, tz_minuteswest));
+	/* constants used by the vdso */
+	DEFINE(CLOCK_REALTIME, CLOCK_REALTIME);
+	DEFINE(CLOCK_MONOTONIC, CLOCK_MONOTONIC);
+	DEFINE(CLOCK_REALTIME_RES, MONOTONIC_RES_NSEC);
+
 	return 0;
 }
Index: quilt-2.6/arch/s390/kernel/Makefile
===================================================================
--- quilt-2.6.orig/arch/s390/kernel/Makefile
+++ quilt-2.6/arch/s390/kernel/Makefile
@@ -13,8 +13,9 @@ CFLAGS_smp.o	:= -Wno-nonnull
 CFLAGS_ptrace.o		+= -DUTS_MACHINE='"$(UTS_MACHINE)"'
 
 obj-y	:=  bitmap.o traps.o time.o process.o base.o early.o \
-            setup.o sys_s390.o ptrace.o signal.o cpcmd.o ebcdic.o \
-	    s390_ext.o debug.o irq.o ipl.o dis.o diag.o mem_detect.o
+	    setup.o sys_s390.o ptrace.o signal.o cpcmd.o ebcdic.o \
+	    s390_ext.o debug.o irq.o ipl.o dis.o diag.o mem_detect.o \
+	    vdso.o
 
 obj-y	+= $(if $(CONFIG_64BIT),entry64.o,entry.o)
 obj-y	+= $(if $(CONFIG_64BIT),reipl64.o,reipl.o)
@@ -39,3 +40,7 @@ S390_KEXEC_OBJS := machine_kexec.o crash
 S390_KEXEC_OBJS += $(if $(CONFIG_64BIT),relocate_kernel64.o,relocate_kernel.o)
 obj-$(CONFIG_KEXEC) += $(S390_KEXEC_OBJS)
 
+# vdso
+obj-$(CONFIG_64BIT)		+= vdso64/
+obj-$(CONFIG_32BIT)		+= vdso32/
+obj-$(CONFIG_COMPAT)		+= vdso32/
Index: quilt-2.6/arch/s390/kernel/time.c
===================================================================
--- quilt-2.6.orig/arch/s390/kernel/time.c
+++ quilt-2.6/arch/s390/kernel/time.c
@@ -36,6 +36,7 @@
 #include <asm/delay.h>
 #include <asm/s390_ext.h>
 #include <asm/div64.h>
+#include <asm/vdso.h>
 #include <asm/irq.h>
 #include <asm/irq_regs.h>
 #include <asm/timer.h>
@@ -223,6 +224,36 @@ static struct clocksource clocksource_to
 };
 
 
+void update_vsyscall(struct timespec *wall_time, struct clocksource *clock)
+{
+	if (clock != &clocksource_tod)
+		return;
+
+	/* Make userspace gettimeofday spin until we're done. */
+	++vdso_data->tb_update_count;
+	smp_mb();
+	vdso_data->xtime_tod_stamp = clock->cycle_last;
+	vdso_data->xtime_clock_sec = xtime.tv_sec;
+	vdso_data->xtime_clock_nsec = xtime.tv_nsec;
+	vdso_data->wtom_clock_sec = wall_to_monotonic.tv_sec;
+	vdso_data->wtom_clock_nsec = wall_to_monotonic.tv_nsec;
+	smp_wmb();
+	++(vdso_data->tb_update_count);
+}
+
+extern struct timezone sys_tz;
+
+void update_vsyscall_tz(void)
+{
+	/* Make userspace gettimeofday spin until we're done. */
+	++vdso_data->tb_update_count;
+	smp_mb();
+	vdso_data->tz_minuteswest = sys_tz.tz_minuteswest;
+	vdso_data->tz_dsttime = sys_tz.tz_dsttime;
+	smp_mb();
+	++vdso_data->tb_update_count;
+}
+
 /*
  * Initialize the TOD clock and the CPU timer of
  * the boot cpu.
Index: quilt-2.6/arch/s390/kernel/vdso32/clock_getres.S
===================================================================
--- /dev/null
+++ quilt-2.6/arch/s390/kernel/vdso32/clock_getres.S
@@ -0,0 +1,39 @@
+/*
+ * Userland implementation of clock_getres() for 32 bits processes in a
+ * s390 kernel for use in the vDSO
+ *
+ *  Copyright IBM Corp. 2008
+ *  Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License (version 2 only)
+ * as published by the Free Software Foundation.
+ */
+#include <asm/vdso.h>
+#include <asm/asm-offsets.h>
+#include <asm/unistd.h>
+
+	.text
+	.align 4
+	.globl __kernel_clock_getres
+	.type  __kernel_clock_getres,@function
+__kernel_clock_getres:
+	.cfi_startproc
+	chi	%r2,CLOCK_REALTIME
+	je	0f
+	chi	%r2,CLOCK_MONOTONIC
+	jne	3f
+0:	ltr	%r3,%r3
+	jz	2f				/* res == NULL */
+	basr	%r1,0
+1:	l	%r0,4f-1b(%r1)
+	xc	0(4,%r3),0(%r3)			/* set tp->tv_sec to zero */
+	st	%r0,4(%r3)			/* store tp->tv_usec */
+2:	lhi	%r2,0
+	br	%r14
+3:	lhi	%r1,__NR_clock_getres		/* fallback to svc */
+	svc	0
+	br	%r14
+4:	.long	CLOCK_REALTIME_RES
+	.cfi_endproc
+	.size	__kernel_clock_getres,.-__kernel_clock_getres
Index: quilt-2.6/arch/s390/kernel/vdso32/clock_gettime.S
===================================================================
--- /dev/null
+++ quilt-2.6/arch/s390/kernel/vdso32/clock_gettime.S
@@ -0,0 +1,128 @@
+/*
+ * Userland implementation of clock_gettime() for 32 bits processes in a
+ * s390 kernel for use in the vDSO
+ *
+ *  Copyright IBM Corp. 2008
+ *  Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License (version 2 only)
+ * as published by the Free Software Foundation.
+ */
+#include <asm/vdso.h>
+#include <asm/asm-offsets.h>
+#include <asm/unistd.h>
+
+	.text
+	.align 4
+	.globl __kernel_clock_gettime
+	.type  __kernel_clock_gettime,@function
+__kernel_clock_gettime:
+	.cfi_startproc
+	basr	%r5,0
+0:	al	%r5,21f-0b(%r5)			/* get &_vdso_data */
+	chi	%r2,CLOCK_REALTIME
+	je	10f
+	chi	%r2,CLOCK_MONOTONIC
+	jne	19f
+
+	/* CLOCK_MONOTONIC */
+	ltr	%r3,%r3
+	jz	9f				/* tp == NULL */
+1:	l	%r4,__VDSO_UPD_COUNT+4(%r5)	/* load update counter */
+	tml	%r4,0x0001			/* pending update ? loop */
+	jnz	1b
+	stck	24(%r15)			/* Store TOD clock */
+	lm	%r0,%r1,24(%r15)
+	s	%r0,__VDSO_XTIME_STAMP(%r5)	/* TOD - cycle_last */
+	sl	%r1,__VDSO_XTIME_STAMP+4(%r5)
+	brc	3,2f
+	ahi	%r0,-1
+2:	mhi	%r0,1000			/* cyc2ns(clock,cycle_delta) */
+	lr	%r2,%r0
+	lhi	%r0,1000
+	ltr	%r1,%r1
+	mr	%r0,%r0
+	jnm	3f
+	ahi	%r0,1000
+3:	alr	%r0,%r2
+	srdl	%r0,12
+	al	%r0,__VDSO_XTIME_NSEC(%r5)	/*  + xtime */
+	al	%r1,__VDSO_XTIME_NSEC+4(%r5)
+	brc	12,4f
+	ahi	%r0,1
+4:	l	%r2,__VDSO_XTIME_SEC+4(%r5)
+	al	%r0,__VDSO_WTOM_NSEC(%r5)	/*  + wall_to_monotonic */
+	al	%r1,__VDSO_WTOM_NSEC+4(%r5)
+	brc	12,5f
+	ahi	%r0,1
+5:	al	%r2,__VDSO_WTOM_SEC+4(%r5)
+	cl	%r4,__VDSO_UPD_COUNT+4(%r5)	/* check update counter */
+	jne	1b
+	basr	%r5,0
+6:	ltr	%r0,%r0
+	jnz	7f
+	cl	%r1,20f-6b(%r5)
+	jl	8f
+7:	ahi	%r2,1
+	sl	%r1,20f-6b(%r5)
+	brc	3,6b
+	ahi	%r0,-1
+	j	6b
+8:	st	%r2,0(%r3)			/* store tp->tv_sec */
+	st	%r1,4(%r3)			/* store tp->tv_nsec */
+9:	lhi	%r2,0
+	br	%r14
+
+	/* CLOCK_REALTIME */
+10:	ltr	%r3,%r3				/* tp == NULL */
+	jz	18f
+11:	l	%r4,__VDSO_UPD_COUNT+4(%r5)	/* load update counter */
+	tml	%r4,0x0001			/* pending update ? loop */
+	jnz	11b
+	stck	24(%r15)			/* Store TOD clock */
+	lm	%r0,%r1,24(%r15)
+	s	%r0,__VDSO_XTIME_STAMP(%r5)	/* TOD - cycle_last */
+	sl	%r1,__VDSO_XTIME_STAMP+4(%r5)
+	brc	3,12f
+	ahi	%r0,-1
+12:	mhi	%r0,1000			/* cyc2ns(clock,cycle_delta) */
+	lr	%r2,%r0
+	lhi	%r0,1000
+	ltr	%r1,%r1
+	mr	%r0,%r0
+	jnm	13f
+	ahi	%r0,1000
+13:	alr	%r0,%r2
+	srdl	%r0,12
+	al	%r0,__VDSO_XTIME_NSEC(%r5)	/*  + xtime */
+	al	%r1,__VDSO_XTIME_NSEC+4(%r5)
+	brc	12,14f
+	ahi	%r0,1
+14:	l	%r2,__VDSO_XTIME_SEC+4(%r5)
+	cl	%r4,__VDSO_UPD_COUNT+4(%r5)	/* check update counter */
+	jne	11b
+	basr	%r5,0
+15:	ltr	%r0,%r0
+	jnz	16f
+	cl	%r1,20f-15b(%r5)
+	jl	17f
+16:	ahi	%r2,1
+	sl	%r1,20f-15b(%r5)
+	brc	3,15b
+	ahi	%r0,-1
+	j	15b
+17:	st	%r2,0(%r3)			/* store tp->tv_sec */
+	st	%r1,4(%r3)			/* store tp->tv_nsec */
+18:	lhi	%r2,0
+	br	%r14
+
+	/* Fallback to system call */
+19:	lhi	%r1,__NR_clock_gettime
+	svc	0
+	br	%r14
+
+20:	.long	1000000000
+21:	.long	_vdso_data - 0b
+	.cfi_endproc
+	.size	__kernel_clock_gettime,.-__kernel_clock_gettime
Index: quilt-2.6/arch/s390/kernel/vdso32/gettimeofday.S
===================================================================
--- /dev/null
+++ quilt-2.6/arch/s390/kernel/vdso32/gettimeofday.S
@@ -0,0 +1,82 @@
+/*
+ * Userland implementation of gettimeofday() for 32 bits processes in a
+ * s390 kernel for use in the vDSO
+ *
+ *  Copyright IBM Corp. 2008
+ *  Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License (version 2 only)
+ * as published by the Free Software Foundation.
+ */
+#include <asm/vdso.h>
+#include <asm/asm-offsets.h>
+#include <asm/unistd.h>
+
+#include <asm/vdso.h>
+#include <asm/asm-offsets.h>
+#include <asm/unistd.h>
+
+	.text
+	.align 4
+	.globl __kernel_gettimeofday
+	.type  __kernel_gettimeofday,@function
+__kernel_gettimeofday:
+	.cfi_startproc
+	basr	%r5,0
+0:	al	%r5,13f-0b(%r5)			/* get &_vdso_data */
+1:	ltr	%r3,%r3				/* check if tz is NULL */
+	je	2f
+	mvc	0(8,%r3),__VDSO_TIMEZONE(%r5)
+2:	ltr	%r2,%r2				/* check if tv is NULL */
+	je	10f
+	l	%r4,__VDSO_UPD_COUNT+4(%r5)	/* load update counter */
+	tml	%r4,0x0001			/* pending update ? loop */
+	jnz	1b
+	stck	24(%r15)			/* Store TOD clock */
+	lm	%r0,%r1,24(%r15)
+	s	%r0,__VDSO_XTIME_STAMP(%r5)	/* TOD - cycle_last */
+	sl	%r1,__VDSO_XTIME_STAMP+4(%r5)
+	brc	3,3f
+	ahi	%r0,-1
+3:	mhi	%r0,1000			/* cyc2ns(clock,cycle_delta) */
+	st	%r0,24(%r15)
+	lhi	%r0,1000
+	ltr	%r1,%r1
+	mr	%r0,%r0
+	jnm	4f
+	ahi	%r0,1000
+4:	al	%r0,24(%r15)
+	srdl	%r0,12
+	al	%r0,__VDSO_XTIME_NSEC(%r5)	/*  + xtime */
+	al	%r1,__VDSO_XTIME_NSEC+4(%r5)
+	brc	12,5f
+	ahi	%r0,1
+5:	mvc	24(4,%r15),__VDSO_XTIME_SEC+4(%r5)
+	cl	%r4,__VDSO_UPD_COUNT+4(%r5)	/* check update counter */
+	jne	1b
+	l	%r4,24(%r15)			/* get tv_sec from stack */
+	basr	%r5,0
+6:	ltr	%r0,%r0
+	jnz	7f
+	cl	%r1,11f-6b(%r5)
+	jl	8f
+7:	ahi	%r4,1
+	sl	%r1,11f-6b(%r5)
+	brc	3,6b
+	ahi	%r0,-1
+	j	6b
+8:	st	%r4,0(%r2)			/* store tv->tv_sec */
+	ltr	%r1,%r1
+	m	%r0,12f-6b(%r5)
+	jnm	9f
+	al	%r0,12f-6b(%r5)
+9:	srl	%r0,6
+	st	%r0,4(%r2)			/* store tv->tv_usec */
+10:	slr	%r2,%r2
+	br	%r14
+11:	.long	1000000000
+12:	.long	274877907
+13:	.long	_vdso_data - 0b
+	.cfi_endproc
+	.size	__kernel_gettimeofday,.-__kernel_gettimeofday
Index: quilt-2.6/arch/s390/kernel/vdso32/Makefile
===================================================================
--- /dev/null
+++ quilt-2.6/arch/s390/kernel/vdso32/Makefile
@@ -0,0 +1,55 @@
+# List of files in the vdso, has to be asm only for now
+
+obj-vdso32 = gettimeofday.o clock_getres.o clock_gettime.o note.o
+
+# Build rules
+
+targets := $(obj-vdso32) vdso32.so vdso32.so.dbg
+obj-vdso32 := $(addprefix $(obj)/, $(obj-vdso32))
+
+KBUILD_AFLAGS_31 := $(filter-out -m64,$(KBUILD_AFLAGS))
+KBUILD_AFLAGS_31 += -m31 -s
+
+KBUILD_CFLAGS_31 := $(filter-out -m64,$(KBUILD_CFLAGS))
+KBUILD_CFLAGS_31 += -m31 -fPIC -shared -fno-common -fno-builtin
+KBUILD_CFLAGS_31 += -nostdlib -Wl,-soname=linux-vdso32.so.1 \
+			$(call ld-option, -Wl$(comma)--hash-style=sysv)
+
+$(targets:%=$(obj)/%.dbg): KBUILD_CFLAGS = $(KBUILD_CFLAGS_31)
+$(targets:%=$(obj)/%.dbg): KBUILD_AFLAGS = $(KBUILD_AFLAGS_31)
+
+obj-y += vdso32_wrapper.o
+extra-y += vdso32.lds
+CPPFLAGS_vdso32.lds += -P -C -U$(ARCH)
+
+# Force dependency (incbin is bad)
+$(obj)/vdso32_wrapper.o : $(obj)/vdso32.so
+
+# link rule for the .so file, .lds has to be first
+$(obj)/vdso32.so.dbg: $(src)/vdso32.lds $(obj-vdso32)
+	$(call if_changed,vdso32ld)
+
+# strip rule for the .so file
+$(obj)/%.so: OBJCOPYFLAGS := -S
+$(obj)/%.so: $(obj)/%.so.dbg FORCE
+	$(call if_changed,objcopy)
+
+# assembly rules for the .S files
+$(obj-vdso32): %.o: %.S
+	$(call if_changed_dep,vdso32as)
+
+# actual build commands
+quiet_cmd_vdso32ld = VDSO32L $@
+      cmd_vdso32ld = $(CC) $(c_flags) -Wl,-T $^ -o $@
+quiet_cmd_vdso32as = VDSO32A $@
+      cmd_vdso32as = $(CC) $(a_flags) -c -o $@ $<
+
+# install commands for the unstripped file
+quiet_cmd_vdso_install = INSTALL $@
+      cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@
+
+vdso32.so: $(obj)/vdso32.so.dbg
+	@mkdir -p $(MODLIB)/vdso
+	$(call cmd,vdso_install)
+
+vdso_install: vdso32.so
Index: quilt-2.6/arch/s390/kernel/vdso32/note.S
===================================================================
--- /dev/null
+++ quilt-2.6/arch/s390/kernel/vdso32/note.S
@@ -0,0 +1,12 @@
+/*
+ * This supplies .note.* sections to go into the PT_NOTE inside the vDSO text.
+ * Here we can supply some information useful to userland.
+ */
+
+#include <linux/uts.h>
+#include <linux/version.h>
+#include <linux/elfnote.h>
+
+ELFNOTE_START(Linux, 0, "a")
+	.long LINUX_VERSION_CODE
+ELFNOTE_END
Index: quilt-2.6/arch/s390/kernel/vdso32/vdso32.lds.S
===================================================================
--- /dev/null
+++ quilt-2.6/arch/s390/kernel/vdso32/vdso32.lds.S
@@ -0,0 +1,138 @@
+/*
+ * This is the infamous ld script for the 32 bits vdso
+ * library
+ */
+#include <asm/vdso.h>
+
+OUTPUT_FORMAT("elf32-s390", "elf32-s390", "elf32-s390")
+OUTPUT_ARCH(s390:31-bit)
+ENTRY(_start)
+
+SECTIONS
+{
+	. = VDSO32_LBASE + SIZEOF_HEADERS;
+
+	.hash		: { *(.hash) }			:text
+	.gnu.hash	: { *(.gnu.hash) }
+	.dynsym		: { *(.dynsym) }
+	.dynstr		: { *(.dynstr) }
+	.gnu.version	: { *(.gnu.version) }
+	.gnu.version_d	: { *(.gnu.version_d) }
+	.gnu.version_r	: { *(.gnu.version_r) }
+
+	.note		: { *(.note.*) }		:text	:note
+
+	. = ALIGN(16);
+	.text		: {
+		*(.text .stub .text.* .gnu.linkonce.t.*)
+	} :text
+	PROVIDE(__etext = .);
+	PROVIDE(_etext = .);
+	PROVIDE(etext = .);
+
+	/*
+	 * Other stuff is appended to the text segment:
+	 */
+	.rodata		: { *(.rodata .rodata.* .gnu.linkonce.r.*) }
+	.rodata1	: { *(.rodata1) }
+
+	.dynamic	: { *(.dynamic) }		:text	:dynamic
+
+	.eh_frame_hdr	: { *(.eh_frame_hdr) }		:text	:eh_frame_hdr
+	.eh_frame	: { KEEP (*(.eh_frame)) }	:text
+	.gcc_except_table : { *(.gcc_except_table .gcc_except_table.*) }
+
+	.rela.dyn ALIGN(8) : { *(.rela.dyn) }
+	.got ALIGN(8)	: { *(.got .toc) }
+
+	_end = .;
+	PROVIDE(end = .);
+
+	/*
+	 * Stabs debugging sections are here too.
+	 */
+	.stab	       0 : { *(.stab) }
+	.stabstr       0 : { *(.stabstr) }
+	.stab.excl     0 : { *(.stab.excl) }
+	.stab.exclstr  0 : { *(.stab.exclstr) }
+	.stab.index    0 : { *(.stab.index) }
+	.stab.indexstr 0 : { *(.stab.indexstr) }
+	.comment       0 : { *(.comment) }
+
+	/*
+	 * DWARF debug sections.
+	 * Symbols in the DWARF debugging sections are relative to the
+	 * beginning of the section so we begin them at 0.
+	 */
+	/* DWARF 1 */
+	.debug		0 : { *(.debug) }
+	.line		0 : { *(.line) }
+	/* GNU DWARF 1 extensions */
+	.debug_srcinfo	0 : { *(.debug_srcinfo) }
+	.debug_sfnames	0 : { *(.debug_sfnames) }
+	/* DWARF 1.1 and DWARF 2 */
+	.debug_aranges	0 : { *(.debug_aranges) }
+	.debug_pubnames 0 : { *(.debug_pubnames) }
+	/* DWARF 2 */
+	.debug_info	0 : { *(.debug_info .gnu.linkonce.wi.*) }
+	.debug_abbrev	0 : { *(.debug_abbrev) }
+	.debug_line	0 : { *(.debug_line) }
+	.debug_frame	0 : { *(.debug_frame) }
+	.debug_str	0 : { *(.debug_str) }
+	.debug_loc	0 : { *(.debug_loc) }
+	.debug_macinfo	0 : { *(.debug_macinfo) }
+	/* SGI/MIPS DWARF 2 extensions */
+	.debug_weaknames 0 : { *(.debug_weaknames) }
+	.debug_funcnames 0 : { *(.debug_funcnames) }
+	.debug_typenames 0 : { *(.debug_typenames) }
+	.debug_varnames  0 : { *(.debug_varnames) }
+	/* DWARF 3 */
+	.debug_pubtypes 0 : { *(.debug_pubtypes) }
+	.debug_ranges	0 : { *(.debug_ranges) }
+	.gnu.attributes 0 : { KEEP (*(.gnu.attributes)) }
+
+	. = ALIGN(4096);
+	PROVIDE(_vdso_data = .);
+
+	/DISCARD/	: {
+		*(.note.GNU-stack)
+		*(.branch_lt)
+		*(.data .data.* .gnu.linkonce.d.* .sdata*)
+		*(.bss .sbss .dynbss .dynsbss)
+	}
+}
+
+/*
+ * Very old versions of ld do not recognize this name token; use the constant.
+ */
+#define PT_GNU_EH_FRAME	0x6474e550
+
+/*
+ * We must supply the ELF program headers explicitly to get just one
+ * PT_LOAD segment, and set the flags explicitly to make segments read-only.
+ */
+PHDRS
+{
+	text		PT_LOAD FILEHDR PHDRS FLAGS(5);	/* PF_R|PF_X */
+	dynamic		PT_DYNAMIC FLAGS(4);		/* PF_R */
+	note		PT_NOTE FLAGS(4);		/* PF_R */
+	eh_frame_hdr	PT_GNU_EH_FRAME;
+}
+
+/*
+ * This controls what symbols we export from the DSO.
+ */
+VERSION
+{
+	VDSO_VERSION_STRING {
+	global:
+		/*
+		 * Has to be there for the kernel to find
+		 */
+		__kernel_gettimeofday;
+		__kernel_clock_gettime;
+		__kernel_clock_getres;
+
+	local: *;
+	};
+}
Index: quilt-2.6/arch/s390/kernel/vdso32/vdso32_wrapper.S
===================================================================
--- /dev/null
+++ quilt-2.6/arch/s390/kernel/vdso32/vdso32_wrapper.S
@@ -0,0 +1,13 @@
+#include <linux/init.h>
+#include <asm/page.h>
+
+	.section ".data.page_aligned"
+
+	.globl vdso32_start, vdso32_end
+	.balign PAGE_SIZE
+vdso32_start:
+	.incbin "arch/s390/kernel/vdso32/vdso32.so"
+	.balign PAGE_SIZE
+vdso32_end:
+
+	.previous
Index: quilt-2.6/arch/s390/kernel/vdso64/clock_getres.S
===================================================================
--- /dev/null
+++ quilt-2.6/arch/s390/kernel/vdso64/clock_getres.S
@@ -0,0 +1,39 @@
+/*
+ * Userland implementation of clock_getres() for 64 bits processes in a
+ * s390 kernel for use in the vDSO
+ *
+ *  Copyright IBM Corp. 2008
+ *  Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License (version 2 only)
+ * as published by the Free Software Foundation.
+ */
+#include <asm/vdso.h>
+#include <asm/asm-offsets.h>
+#include <asm/unistd.h>
+
+	.text
+	.align 4
+	.globl __kernel_clock_getres
+	.type  __kernel_clock_getres,@function
+__kernel_clock_getres:
+	.cfi_startproc
+	cghi	%r2,CLOCK_REALTIME
+	je	0f
+	cghi	%r2,CLOCK_MONOTONIC
+	jne	2f
+0:	ltgr	%r3,%r3
+	jz	1f				/* res == NULL */
+	larl	%r1,3f
+	lg	%r0,0(%r1)
+	xc	0(8,%r3),0(%r3)			/* set tp->tv_sec to zero */
+	stg	%r0,8(%r3)			/* store tp->tv_usec */
+1:	lghi	%r2,0
+	br	%r14
+2:	lghi	%r1,__NR_clock_getres		/* fallback to svc */
+	svc	0
+	br	%r14
+3:	.quad	CLOCK_REALTIME_RES
+	.cfi_endproc
+	.size	__kernel_clock_getres,.-__kernel_clock_getres
Index: quilt-2.6/arch/s390/kernel/vdso64/clock_gettime.S
===================================================================
--- /dev/null
+++ quilt-2.6/arch/s390/kernel/vdso64/clock_gettime.S
@@ -0,0 +1,89 @@
+/*
+ * Userland implementation of clock_gettime() for 64 bits processes in a
+ * s390 kernel for use in the vDSO
+ *
+ *  Copyright IBM Corp. 2008
+ *  Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License (version 2 only)
+ * as published by the Free Software Foundation.
+ */
+#include <asm/vdso.h>
+#include <asm/asm-offsets.h>
+#include <asm/unistd.h>
+
+	.text
+	.align 4
+	.globl __kernel_clock_gettime
+	.type  __kernel_clock_gettime,@function
+__kernel_clock_gettime:
+	.cfi_startproc
+	larl	%r5,_vdso_data
+	cghi	%r2,CLOCK_REALTIME
+	je	4f
+	cghi	%r2,CLOCK_MONOTONIC
+	jne	9f
+
+	/* CLOCK_MONOTONIC */
+	ltgr	%r3,%r3
+	jz	3f				/* tp == NULL */
+0:	lg	%r4,__VDSO_UPD_COUNT(%r5)	/* load update counter */
+	tmll	%r4,0x0001			/* pending update ? loop */
+	jnz	0b
+	stck	48(%r15)			/* Store TOD clock */
+	lg	%r1,48(%r15)
+	sg	%r1,__VDSO_XTIME_STAMP(%r5)	/* TOD - cycle_last */
+	mghi	%r1,1000
+	srlg	%r1,%r1,12			/* cyc2ns(clock,cycle_delta) */
+	alg	%r1,__VDSO_XTIME_NSEC(%r5)	/*  + xtime */
+	lg	%r0,__VDSO_XTIME_SEC(%r5)
+	alg	%r1,__VDSO_WTOM_NSEC(%r5)	/*  + wall_to_monotonic */
+	alg	%r0,__VDSO_WTOM_SEC(%r5)
+	clg	%r4,__VDSO_UPD_COUNT(%r5)	/* check update counter */
+	jne	0b
+	larl	%r5,10f
+1:	clg	%r1,0(%r5)
+	jl	2f
+	slg	%r1,0(%r5)
+	aghi	%r0,1
+	j	1b
+2:	stg	%r0,0(%r3)			/* store tp->tv_sec */
+	stg	%r1,8(%r3)			/* store tp->tv_nsec */
+3:	lghi	%r2,0
+	br	%r14
+
+	/* CLOCK_REALTIME */
+4:	ltr	%r3,%r3				/* tp == NULL */
+	jz	8f
+5:	lg	%r4,__VDSO_UPD_COUNT(%r5)	/* load update counter */
+	tmll	%r4,0x0001			/* pending update ? loop */
+	jnz	5b
+	stck	48(%r15)			/* Store TOD clock */
+	lg	%r1,48(%r15)
+	sg	%r1,__VDSO_XTIME_STAMP(%r5)	/* TOD - cycle_last */
+	mghi	%r1,1000
+	srlg	%r1,%r1,12			/* cyc2ns(clock,cycle_delta) */
+	alg	%r1,__VDSO_XTIME_NSEC(%r5)	/*  + xtime */
+	lg	%r0,__VDSO_XTIME_SEC(%r5)
+	clg	%r4,__VDSO_UPD_COUNT(%r5)	/* check update counter */
+	jne	5b
+	larl	%r5,10f
+6:	clg	%r1,0(%r5)
+	jl	7f
+	slg	%r1,0(%r5)
+	aghi	%r0,1
+	j	6b
+7:	stg	%r0,0(%r3)			/* store tp->tv_sec */
+	stg	%r1,8(%r3)			/* store tp->tv_nsec */
+8:	lghi	%r2,0
+	br	%r14
+
+	/* Fallback to system call */
+9:	lghi	%r1,__NR_clock_gettime
+	svc	0
+	br	%r14
+
+10:	.quad	1000000000
+	.cfi_endproc
+	.size	__kernel_clock_gettime,.-__kernel_clock_gettime
Index: quilt-2.6/arch/s390/kernel/vdso64/gettimeofday.S
===================================================================
--- /dev/null
+++ quilt-2.6/arch/s390/kernel/vdso64/gettimeofday.S
@@ -0,0 +1,56 @@
+/*
+ * Userland implementation of gettimeofday() for 64 bits processes in a
+ * s390 kernel for use in the vDSO
+ *
+ *  Copyright IBM Corp. 2008
+ *  Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License (version 2 only)
+ * as published by the Free Software Foundation.
+ */
+#include <asm/vdso.h>
+#include <asm/asm-offsets.h>
+#include <asm/unistd.h>
+
+	.text
+	.align 4
+	.globl __kernel_gettimeofday
+	.type  __kernel_gettimeofday,@function
+__kernel_gettimeofday:
+	.cfi_startproc
+	larl	%r5,_vdso_data
+0:	ltgr	%r3,%r3				/* check if tz is NULL */
+	je	1f
+	mvc	0(8,%r3),__VDSO_TIMEZONE(%r5)
+1:	ltgr	%r2,%r2				/* check if tv is NULL */
+	je	4f
+	lg	%r4,__VDSO_UPD_COUNT(%r5)	/* load update counter */
+	tmll	%r4,0x0001			/* pending update ? loop */
+	jnz	0b
+	stck	48(%r15)			/* Store TOD clock */
+	lg	%r1,48(%r15)
+	sg	%r1,__VDSO_XTIME_STAMP(%r5)	/* TOD - cycle_last */
+	mghi	%r1,1000
+	srlg	%r1,%r1,12			/* cyc2ns(clock,cycle_delta) */
+	alg	%r1,__VDSO_XTIME_NSEC(%r5)	/*  + xtime.tv_nsec */
+	lg	%r0,__VDSO_XTIME_SEC(%r5)	/* xtime.tv_sec */
+	clg	%r4,__VDSO_UPD_COUNT(%r5)	/* check update counter */
+	jne	0b
+	larl	%r5,5f
+2:	clg	%r1,0(%r5)
+	jl	3f
+	slg	%r1,0(%r5)
+	aghi	%r0,1
+	j	2b
+3:	stg	%r0,0(%r2)			/* store tv->tv_sec */
+	slgr	%r0,%r0				/* tv_nsec -> tv_usec */
+	ml	%r0,8(%r5)
+	srlg	%r0,%r0,6
+	stg	%r0,8(%r2)			/* store tv->tv_usec */
+4:	lghi	%r2,0
+	br	%r14
+5:	.quad	1000000000
+	.long	274877907
+	.cfi_endproc
+	.size	__kernel_gettimeofday,.-__kernel_gettimeofday
Index: quilt-2.6/arch/s390/kernel/vdso64/Makefile
===================================================================
--- /dev/null
+++ quilt-2.6/arch/s390/kernel/vdso64/Makefile
@@ -0,0 +1,55 @@
+# List of files in the vdso, has to be asm only for now
+
+obj-vdso64 = gettimeofday.o clock_getres.o clock_gettime.o note.o
+
+# Build rules
+
+targets := $(obj-vdso64) vdso64.so vdso64.so.dbg
+obj-vdso64 := $(addprefix $(obj)/, $(obj-vdso64))
+
+KBUILD_AFLAGS_64 := $(filter-out -m64,$(KBUILD_AFLAGS))
+KBUILD_AFLAGS_64 += -m64 -s
+
+KBUILD_CFLAGS_64 := $(filter-out -m64,$(KBUILD_CFLAGS))
+KBUILD_CFLAGS_64 += -m64 -fPIC -shared -fno-common -fno-builtin
+KBUILD_CFLAGS_64 += -nostdlib -Wl,-soname=linux-vdso64.so.1 \
+			$(call ld-option, -Wl$(comma)--hash-style=sysv)
+
+$(targets:%=$(obj)/%.dbg): KBUILD_CFLAGS = $(KBUILD_CFLAGS_64)
+$(targets:%=$(obj)/%.dbg): KBUILD_AFLAGS = $(KBUILD_AFLAGS_64)
+
+obj-y += vdso64_wrapper.o
+extra-y += vdso64.lds
+CPPFLAGS_vdso64.lds += -P -C -U$(ARCH)
+
+# Force dependency (incbin is bad)
+$(obj)/vdso64_wrapper.o : $(obj)/vdso64.so
+
+# link rule for the .so file, .lds has to be first
+$(obj)/vdso64.so.dbg: $(src)/vdso64.lds $(obj-vdso64)
+	$(call if_changed,vdso64ld)
+
+# strip rule for the .so file
+$(obj)/%.so: OBJCOPYFLAGS := -S
+$(obj)/%.so: $(obj)/%.so.dbg FORCE
+	$(call if_changed,objcopy)
+
+# assembly rules for the .S files
+$(obj-vdso64): %.o: %.S
+	$(call if_changed_dep,vdso64as)
+
+# actual build commands
+quiet_cmd_vdso64ld = VDSO64L $@
+      cmd_vdso64ld = $(CC) $(c_flags) -Wl,-T $^ -o $@
+quiet_cmd_vdso64as = VDSO64A $@
+      cmd_vdso64as = $(CC) $(a_flags) -c -o $@ $<
+
+# install commands for the unstripped file
+quiet_cmd_vdso_install = INSTALL $@
+      cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@
+
+vdso64.so: $(obj)/vdso64.so.dbg
+	@mkdir -p $(MODLIB)/vdso
+	$(call cmd,vdso_install)
+
+vdso_install: vdso64.so
Index: quilt-2.6/arch/s390/kernel/vdso64/note.S
===================================================================
--- /dev/null
+++ quilt-2.6/arch/s390/kernel/vdso64/note.S
@@ -0,0 +1,12 @@
+/*
+ * This supplies .note.* sections to go into the PT_NOTE inside the vDSO text.
+ * Here we can supply some information useful to userland.
+ */
+
+#include <linux/uts.h>
+#include <linux/version.h>
+#include <linux/elfnote.h>
+
+ELFNOTE_START(Linux, 0, "a")
+	.long LINUX_VERSION_CODE
+ELFNOTE_END
Index: quilt-2.6/arch/s390/kernel/vdso64/vdso64.lds.S
===================================================================
--- /dev/null
+++ quilt-2.6/arch/s390/kernel/vdso64/vdso64.lds.S
@@ -0,0 +1,138 @@
+/*
+ * This is the infamous ld script for the 64 bits vdso
+ * library
+ */
+#include <asm/vdso.h>
+
+OUTPUT_FORMAT("elf64-s390", "elf64-s390", "elf64-s390")
+OUTPUT_ARCH(s390:64-bit)
+ENTRY(_start)
+
+SECTIONS
+{
+	. = VDSO64_LBASE + SIZEOF_HEADERS;
+
+	.hash		: { *(.hash) }			:text
+	.gnu.hash	: { *(.gnu.hash) }
+	.dynsym		: { *(.dynsym) }
+	.dynstr		: { *(.dynstr) }
+	.gnu.version	: { *(.gnu.version) }
+	.gnu.version_d	: { *(.gnu.version_d) }
+	.gnu.version_r	: { *(.gnu.version_r) }
+
+	.note		: { *(.note.*) }		:text	:note
+
+	. = ALIGN(16);
+	.text		: {
+		*(.text .stub .text.* .gnu.linkonce.t.*)
+	} :text
+	PROVIDE(__etext = .);
+	PROVIDE(_etext = .);
+	PROVIDE(etext = .);
+
+	/*
+	 * Other stuff is appended to the text segment:
+	 */
+	.rodata		: { *(.rodata .rodata.* .gnu.linkonce.r.*) }
+	.rodata1	: { *(.rodata1) }
+
+	.dynamic	: { *(.dynamic) }		:text	:dynamic
+
+	.eh_frame_hdr	: { *(.eh_frame_hdr) }		:text	:eh_frame_hdr
+	.eh_frame	: { KEEP (*(.eh_frame)) }	:text
+	.gcc_except_table : { *(.gcc_except_table .gcc_except_table.*) }
+
+	.rela.dyn ALIGN(8) : { *(.rela.dyn) }
+	.got ALIGN(8)	: { *(.got .toc) }
+
+	_end = .;
+	PROVIDE(end = .);
+
+	/*
+	 * Stabs debugging sections are here too.
+	 */
+	.stab	       0 : { *(.stab) }
+	.stabstr       0 : { *(.stabstr) }
+	.stab.excl     0 : { *(.stab.excl) }
+	.stab.exclstr  0 : { *(.stab.exclstr) }
+	.stab.index    0 : { *(.stab.index) }
+	.stab.indexstr 0 : { *(.stab.indexstr) }
+	.comment       0 : { *(.comment) }
+
+	/*
+	 * DWARF debug sections.
+	 * Symbols in the DWARF debugging sections are relative to the
+	 * beginning of the section so we begin them at 0.
+	 */
+	/* DWARF 1 */
+	.debug		0 : { *(.debug) }
+	.line		0 : { *(.line) }
+	/* GNU DWARF 1 extensions */
+	.debug_srcinfo	0 : { *(.debug_srcinfo) }
+	.debug_sfnames	0 : { *(.debug_sfnames) }
+	/* DWARF 1.1 and DWARF 2 */
+	.debug_aranges	0 : { *(.debug_aranges) }
+	.debug_pubnames 0 : { *(.debug_pubnames) }
+	/* DWARF 2 */
+	.debug_info	0 : { *(.debug_info .gnu.linkonce.wi.*) }
+	.debug_abbrev	0 : { *(.debug_abbrev) }
+	.debug_line	0 : { *(.debug_line) }
+	.debug_frame	0 : { *(.debug_frame) }
+	.debug_str	0 : { *(.debug_str) }
+	.debug_loc	0 : { *(.debug_loc) }
+	.debug_macinfo	0 : { *(.debug_macinfo) }
+	/* SGI/MIPS DWARF 2 extensions */
+	.debug_weaknames 0 : { *(.debug_weaknames) }
+	.debug_funcnames 0 : { *(.debug_funcnames) }
+	.debug_typenames 0 : { *(.debug_typenames) }
+	.debug_varnames  0 : { *(.debug_varnames) }
+	/* DWARF 3 */
+	.debug_pubtypes 0 : { *(.debug_pubtypes) }
+	.debug_ranges	0 : { *(.debug_ranges) }
+	.gnu.attributes 0 : { KEEP (*(.gnu.attributes)) }
+
+	. = ALIGN(4096);
+	PROVIDE(_vdso_data = .);
+
+	/DISCARD/	: {
+		*(.note.GNU-stack)
+		*(.branch_lt)
+		*(.data .data.* .gnu.linkonce.d.* .sdata*)
+		*(.bss .sbss .dynbss .dynsbss)
+	}
+}
+
+/*
+ * Very old versions of ld do not recognize this name token; use the constant.
+ */
+#define PT_GNU_EH_FRAME	0x6474e550
+
+/*
+ * We must supply the ELF program headers explicitly to get just one
+ * PT_LOAD segment, and set the flags explicitly to make segments read-only.
+ */
+PHDRS
+{
+	text		PT_LOAD FILEHDR PHDRS FLAGS(5);	/* PF_R|PF_X */
+	dynamic		PT_DYNAMIC FLAGS(4);		/* PF_R */
+	note		PT_NOTE FLAGS(4);		/* PF_R */
+	eh_frame_hdr	PT_GNU_EH_FRAME;
+}
+
+/*
+ * This controls what symbols we export from the DSO.
+ */
+VERSION
+{
+	VDSO_VERSION_STRING {
+	global:
+		/*
+		 * Has to be there for the kernel to find
+		 */
+		__kernel_gettimeofday;
+		__kernel_clock_gettime;
+		__kernel_clock_getres;
+
+	local: *;
+	};
+}
Index: quilt-2.6/arch/s390/kernel/vdso64/vdso64_wrapper.S
===================================================================
--- /dev/null
+++ quilt-2.6/arch/s390/kernel/vdso64/vdso64_wrapper.S
@@ -0,0 +1,13 @@
+#include <linux/init.h>
+#include <asm/page.h>
+
+	.section ".data.page_aligned"
+
+	.globl vdso64_start, vdso64_end
+	.balign PAGE_SIZE
+vdso64_start:
+	.incbin "arch/s390/kernel/vdso64/vdso64.so"
+	.balign PAGE_SIZE
+vdso64_end:
+
+	.previous
Index: quilt-2.6/arch/s390/kernel/vdso.c
===================================================================
--- /dev/null
+++ quilt-2.6/arch/s390/kernel/vdso.c
@@ -0,0 +1,232 @@
+/*
+ * vdso setup for s390
+ *
+ *  Copyright IBM Corp. 2008
+ *  Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License (version 2 only)
+ * as published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/stddef.h>
+#include <linux/unistd.h>
+#include <linux/slab.h>
+#include <linux/user.h>
+#include <linux/elf.h>
+#include <linux/security.h>
+#include <linux/bootmem.h>
+
+#include <asm/pgtable.h>
+#include <asm/system.h>
+#include <asm/processor.h>
+#include <asm/mmu.h>
+#include <asm/mmu_context.h>
+#include <asm/sections.h>
+#include <asm/vdso.h>
+
+/* Max supported size for symbol names */
+#define MAX_SYMNAME	64
+
+#if defined(CONFIG_32BIT) || defined(CONFIG_COMPAT)
+extern char vdso32_start, vdso32_end;
+static void *vdso32_kbase = &vdso32_start;
+static unsigned int vdso32_pages;
+static struct page **vdso32_pagelist;
+#endif
+
+#ifdef CONFIG_64BIT
+extern char vdso64_start, vdso64_end;
+static void *vdso64_kbase = &vdso64_start;
+static unsigned int vdso64_pages;
+static struct page **vdso64_pagelist;
+#endif /* CONFIG_64BIT */
+
+/*
+ * Should the kernel map a VDSO page into processes and pass its
+ * address down to glibc upon exec()?
+ */
+unsigned int __read_mostly vdso_enabled = 1;
+
+static int __init vdso_setup(char *s)
+{
+	vdso_enabled = simple_strtoul(s, NULL, 0);
+	return 1;
+}
+__setup("vdso=", vdso_setup);
+
+/*
+ * The vdso data page
+ */
+static union {
+	struct vdso_data	data;
+	u8			page[PAGE_SIZE];
+} vdso_data_store __attribute__((__section__(".data.page_aligned")));
+struct vdso_data *vdso_data = &vdso_data_store.data;
+
+/*
+ * This is called from binfmt_elf, we create the special vma for the
+ * vDSO and insert it into the mm struct tree
+ */
+int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
+{
+	struct mm_struct *mm = current->mm;
+	struct page **vdso_pagelist;
+	unsigned long vdso_pages;
+	unsigned long vdso_base;
+	int rc;
+
+	/*
+	 * Only map the vdso for dynamically linked elf binaries.
+	 */
+	if (!uses_interp)
+		return 0;
+
+	vdso_base = mm->mmap_base;
+#ifdef CONFIG_64BIT
+	vdso_pagelist = vdso64_pagelist;
+	vdso_pages = vdso64_pages;
+#ifdef CONFIG_COMPAT
+	if (test_thread_flag(TIF_31BIT)) {
+		vdso_pagelist = vdso32_pagelist;
+		vdso_pages = vdso32_pages;
+	}
+#endif
+#else
+	vdso_pagelist = vdso32_pagelist;
+	vdso_pages = vdso32_pages;
+#endif
+
+	/*
+	 * vDSO has a problem and was disabled, just don't "enable" it for
+	 * the process
+	 */
+	if (vdso_pages == 0)
+		return 0;
+
+	current->mm->context.vdso_base = 0;
+
+	/*
+	 * pick a base address for the vDSO in process space. We try to put
+	 * it at vdso_base which is the "natural" base for it, but we might
+	 * fail and end up putting it elsewhere.
+	 */
+	down_write(&mm->mmap_sem);
+	vdso_base = get_unmapped_area(NULL, vdso_base,
+				      vdso_pages << PAGE_SHIFT, 0, 0);
+	if (IS_ERR_VALUE(vdso_base)) {
+		rc = vdso_base;
+		goto out_up;
+	}
+
+	/*
+	 * our vma flags don't have VM_WRITE so by default, the process
+	 * isn't allowed to write those pages.
+	 * gdb can break that with ptrace interface, and thus trigger COW
+	 * on those pages but it's then your responsibility to never do that
+	 * on the "data" page of the vDSO or you'll stop getting kernel
+	 * updates and your nice userland gettimeofday will be totally dead.
+	 * It's fine to use that for setting breakpoints in the vDSO code
+	 * pages though
+	 *
+	 * Make sure the vDSO gets into every core dump.
+	 * Dumping its contents makes post-mortem fully interpretable later
+	 * without matching up the same kernel and hardware config to see
+	 * what PC values meant.
+	 */
+	rc = install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT,
+				     VM_READ|VM_EXEC|
+				     VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC|
+				     VM_ALWAYSDUMP,
+				     vdso_pagelist);
+	if (rc)
+		goto out_up;
+
+	/* Put vDSO base into mm struct */
+	current->mm->context.vdso_base = vdso_base;
+
+	up_write(&mm->mmap_sem);
+	return 0;
+
+out_up:
+	up_write(&mm->mmap_sem);
+	return rc;
+}
+
+const char *arch_vma_name(struct vm_area_struct *vma)
+{
+	if (vma->vm_mm && vma->vm_start == vma->vm_mm->context.vdso_base)
+		return "[vdso]";
+	return NULL;
+}
+
+static int __init vdso_init(void)
+{
+	int i;
+
+#if defined(CONFIG_32BIT) || defined(CONFIG_COMPAT)
+	/* Calculate the size of the 32 bit vDSO */
+	vdso32_pages = ((&vdso32_end - &vdso32_start
+			 + PAGE_SIZE - 1) >> PAGE_SHIFT) + 1;
+
+	/* Make sure pages are in the correct state */
+	vdso32_pagelist = kzalloc(sizeof(struct page *) * (vdso32_pages + 1),
+				  GFP_KERNEL);
+	BUG_ON(vdso32_pagelist == NULL);
+	for (i = 0; i < vdso32_pages - 1; i++) {
+		struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
+		ClearPageReserved(pg);
+		get_page(pg);
+		vdso32_pagelist[i] = pg;
+	}
+	vdso32_pagelist[vdso32_pages - 1] = virt_to_page(vdso_data);
+	vdso32_pagelist[vdso32_pages] = NULL;
+#endif
+
+#ifdef CONFIG_64BIT
+	/* Calculate the size of the 64 bit vDSO */
+	vdso64_pages = ((&vdso64_end - &vdso64_start
+			 + PAGE_SIZE - 1) >> PAGE_SHIFT) + 1;
+
+	/* Make sure pages are in the correct state */
+	vdso64_pagelist = kzalloc(sizeof(struct page *) * (vdso64_pages + 1),
+				  GFP_KERNEL);
+	BUG_ON(vdso64_pagelist == NULL);
+	for (i = 0; i < vdso64_pages - 1; i++) {
+		struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
+		ClearPageReserved(pg);
+		get_page(pg);
+		vdso64_pagelist[i] = pg;
+	}
+	vdso64_pagelist[vdso64_pages - 1] = virt_to_page(vdso_data);
+	vdso64_pagelist[vdso64_pages] = NULL;
+#endif /* CONFIG_64BIT */
+
+	get_page(virt_to_page(vdso_data));
+
+	smp_wmb();
+
+	return 0;
+}
+arch_initcall(vdso_init);
+
+int in_gate_area_no_task(unsigned long addr)
+{
+	return 0;
+}
+
+int in_gate_area(struct task_struct *task, unsigned long addr)
+{
+	return 0;
+}
+
+struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
+{
+	return NULL;
+}

-- 
blue skies,
   Martin.

"Reality continues to ruin my life." - Calvin.


^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [patch 2/2] introduce vdso on s390
  2008-10-15 17:45 ` [patch 2/2] introduce vdso on s390 Martin Schwidefsky
@ 2008-10-17 15:34   ` Bastian Blank
  2008-10-20 13:06     ` Heiko Carstens
  0 siblings, 1 reply; 5+ messages in thread
From: Bastian Blank @ 2008-10-17 15:34 UTC (permalink / raw)
  To: Martin Schwidefsky; +Cc: linux-kernel, linux-s390, linux-arch, Heiko Carstens

On Wed, Oct 15, 2008 at 07:45:08PM +0200, Martin Schwidefsky wrote:
> +void update_vsyscall(struct timespec *wall_time, struct clocksource *clock)
> +{
> +	if (clock != &clocksource_tod)
> +		return;
> +
> +	/* Make userspace gettimeofday spin until we're done. */
> +	++vdso_data->tb_update_count;
> +	smp_mb();
> +	vdso_data->xtime_tod_stamp = clock->cycle_last;
> +	vdso_data->xtime_clock_sec = xtime.tv_sec;
> +	vdso_data->xtime_clock_nsec = xtime.tv_nsec;
> +	vdso_data->wtom_clock_sec = wall_to_monotonic.tv_sec;
> +	vdso_data->wtom_clock_nsec = wall_to_monotonic.tv_nsec;
> +	smp_wmb();

Different barriers?

> +	++(vdso_data->tb_update_count);

Why ++(...)?

Bastian

-- 
Either one of us, by himself, is expendable.  Both of us are not.
		-- Kirk, "The Devil in the Dark", stardate 3196.1

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [patch 2/2] introduce vdso on s390
  2008-10-17 15:34   ` Bastian Blank
@ 2008-10-20 13:06     ` Heiko Carstens
  0 siblings, 0 replies; 5+ messages in thread
From: Heiko Carstens @ 2008-10-20 13:06 UTC (permalink / raw)
  To: Bastian Blank, Martin Schwidefsky, linux-kernel, linux-s390, linux-arch

On Fri, Oct 17, 2008 at 05:34:36PM +0200, Bastian Blank wrote:
> On Wed, Oct 15, 2008 at 07:45:08PM +0200, Martin Schwidefsky wrote:
> > +void update_vsyscall(struct timespec *wall_time, struct clocksource *clock)
> > +{
> > +	if (clock != &clocksource_tod)
> > +		return;
> > +
> > +	/* Make userspace gettimeofday spin until we're done. */
> > +	++vdso_data->tb_update_count;
> > +	smp_mb();
> > +	vdso_data->xtime_tod_stamp = clock->cycle_last;
> > +	vdso_data->xtime_clock_sec = xtime.tv_sec;
> > +	vdso_data->xtime_clock_nsec = xtime.tv_nsec;
> > +	vdso_data->wtom_clock_sec = wall_to_monotonic.tv_sec;
> > +	vdso_data->wtom_clock_nsec = wall_to_monotonic.tv_nsec;
> > +	smp_wmb();
> 
> Different barriers?

Doesn't matter. They are all the same anyway on s390. But I changed it to
smp_wmb instead.

> > +	++(vdso_data->tb_update_count);
>
> Why ++(...)?

Removed the braces.

^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2008-10-20 13:07 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2008-10-15 17:45 [patch 0/2] vdso support for s390 Martin Schwidefsky
2008-10-15 17:45 ` [patch 1/2] arch_setup_additional_pages arguments Martin Schwidefsky
2008-10-15 17:45 ` [patch 2/2] introduce vdso on s390 Martin Schwidefsky
2008-10-17 15:34   ` Bastian Blank
2008-10-20 13:06     ` Heiko Carstens

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