[S390] introduce vdso on s390
authorMartin Schwidefsky <schwidefsky@de.ibm.com>
Thu, 25 Dec 2008 12:38:36 +0000 (13:38 +0100)
committerMartin Schwidefsky <schwidefsky@de.ibm.com>
Thu, 25 Dec 2008 12:38:55 +0000 (13:38 +0100)
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>
24 files changed:
arch/s390/Kconfig
arch/s390/include/asm/auxvec.h
arch/s390/include/asm/elf.h
arch/s390/include/asm/mmu.h
arch/s390/include/asm/page.h
arch/s390/include/asm/vdso.h [new file with mode: 0644]
arch/s390/kernel/Makefile
arch/s390/kernel/asm-offsets.c
arch/s390/kernel/time.c
arch/s390/kernel/vdso.c [new file with mode: 0644]
arch/s390/kernel/vdso32/Makefile [new file with mode: 0644]
arch/s390/kernel/vdso32/clock_getres.S [new file with mode: 0644]
arch/s390/kernel/vdso32/clock_gettime.S [new file with mode: 0644]
arch/s390/kernel/vdso32/gettimeofday.S [new file with mode: 0644]
arch/s390/kernel/vdso32/note.S [new file with mode: 0644]
arch/s390/kernel/vdso32/vdso32.lds.S [new file with mode: 0644]
arch/s390/kernel/vdso32/vdso32_wrapper.S [new file with mode: 0644]
arch/s390/kernel/vdso64/Makefile [new file with mode: 0644]
arch/s390/kernel/vdso64/clock_getres.S [new file with mode: 0644]
arch/s390/kernel/vdso64/clock_gettime.S [new file with mode: 0644]
arch/s390/kernel/vdso64/gettimeofday.S [new file with mode: 0644]
arch/s390/kernel/vdso64/note.S [new file with mode: 0644]
arch/s390/kernel/vdso64/vdso64.lds.S [new file with mode: 0644]
arch/s390/kernel/vdso64/vdso64_wrapper.S [new file with mode: 0644]

index 8116a33..37bb373 100644 (file)
@@ -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 0d34072..a1f153e 100644 (file)
@@ -1,4 +1,6 @@
 #ifndef __ASMS390_AUXVEC_H
 #define __ASMS390_AUXVEC_H
 
+#define AT_SYSINFO_EHDR                33
+
 #endif
index 261785a..d480f39 100644 (file)
@@ -120,6 +120,10 @@ typedef s390_compat_regs compat_elf_gregset_t;
 #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.
  */
@@ -191,4 +195,16 @@ 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 d2b4ff8..3b59216 100644 (file)
@@ -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 991ba93..32e8f6a 100644 (file)
@@ -152,4 +152,6 @@ void arch_alloc_page(struct page *page, int order);
 #include <asm-generic/memory_model.h>
 #include <asm-generic/page.h>
 
+#define __HAVE_ARCH_GATE_AREA 1
+
 #endif /* _S390_PAGE_H */
diff --git a/arch/s390/include/asm/vdso.h b/arch/s390/include/asm/vdso.h
new file mode 100644 (file)
index 0000000..a44f4fe
--- /dev/null
@@ -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 50f657e..235b948 100644 (file)
@@ -14,7 +14,8 @@ 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
+           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.o
 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 3d144e6..e641f60 100644 (file)
@@ -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 eccefbb..b73bbf3 100644 (file)
@@ -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_tod = {
 };
 
 
+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_wmb();
+       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_wmb();
+       vdso_data->tz_minuteswest = sys_tz.tz_minuteswest;
+       vdso_data->tz_dsttime = sys_tz.tz_dsttime;
+       smp_wmb();
+       ++vdso_data->tb_update_count;
+}
+
 /*
  * Initialize the TOD clock and the CPU timer of
  * the boot cpu.
diff --git a/arch/s390/kernel/vdso.c b/arch/s390/kernel/vdso.c
new file mode 100644 (file)
index 0000000..10a6cce
--- /dev/null
@@ -0,0 +1,234 @@
+/*
+ * 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;
+
+       if (!vdso_enabled)
+               return 0;
+       /*
+        * 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;
+}
diff --git a/arch/s390/kernel/vdso32/Makefile b/arch/s390/kernel/vdso32/Makefile
new file mode 100644 (file)
index 0000000..ca78ad6
--- /dev/null
@@ -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
diff --git a/arch/s390/kernel/vdso32/clock_getres.S b/arch/s390/kernel/vdso32/clock_getres.S
new file mode 100644 (file)
index 0000000..9532c4e
--- /dev/null
@@ -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
diff --git a/arch/s390/kernel/vdso32/clock_gettime.S b/arch/s390/kernel/vdso32/clock_gettime.S
new file mode 100644 (file)
index 0000000..4a98909
--- /dev/null
@@ -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
diff --git a/arch/s390/kernel/vdso32/gettimeofday.S b/arch/s390/kernel/vdso32/gettimeofday.S
new file mode 100644 (file)
index 0000000..c32f29c
--- /dev/null
@@ -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
diff --git a/arch/s390/kernel/vdso32/note.S b/arch/s390/kernel/vdso32/note.S
new file mode 100644 (file)
index 0000000..79a071e
--- /dev/null
@@ -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
diff --git a/arch/s390/kernel/vdso32/vdso32.lds.S b/arch/s390/kernel/vdso32/vdso32.lds.S
new file mode 100644 (file)
index 0000000..a8c379f
--- /dev/null
@@ -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: *;
+       };
+}
diff --git a/arch/s390/kernel/vdso32/vdso32_wrapper.S b/arch/s390/kernel/vdso32/vdso32_wrapper.S
new file mode 100644 (file)
index 0000000..61639a8
--- /dev/null
@@ -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
diff --git a/arch/s390/kernel/vdso64/Makefile b/arch/s390/kernel/vdso64/Makefile
new file mode 100644 (file)
index 0000000..6fc8e82
--- /dev/null
@@ -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
diff --git a/arch/s390/kernel/vdso64/clock_getres.S b/arch/s390/kernel/vdso64/clock_getres.S
new file mode 100644 (file)
index 0000000..488e31a
--- /dev/null
@@ -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
diff --git a/arch/s390/kernel/vdso64/clock_gettime.S b/arch/s390/kernel/vdso64/clock_gettime.S
new file mode 100644 (file)
index 0000000..738a410
--- /dev/null
@@ -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
diff --git a/arch/s390/kernel/vdso64/gettimeofday.S b/arch/s390/kernel/vdso64/gettimeofday.S
new file mode 100644 (file)
index 0000000..f873e75
--- /dev/null
@@ -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
diff --git a/arch/s390/kernel/vdso64/note.S b/arch/s390/kernel/vdso64/note.S
new file mode 100644 (file)
index 0000000..79a071e
--- /dev/null
@@ -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
diff --git a/arch/s390/kernel/vdso64/vdso64.lds.S b/arch/s390/kernel/vdso64/vdso64.lds.S
new file mode 100644 (file)
index 0000000..9f5979d
--- /dev/null
@@ -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: *;
+       };
+}
diff --git a/arch/s390/kernel/vdso64/vdso64_wrapper.S b/arch/s390/kernel/vdso64/vdso64_wrapper.S
new file mode 100644 (file)
index 0000000..d8e2ac1
--- /dev/null
@@ -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