From: Thomas Gleixner <tglx@linutronix.de>
Date: Thu, 11 Oct 2007 09:14:33 +0000 (+0200)
Subject: x86_64: prepare shared kernel/vsyscall.c
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=21a44007745783d8997ed115852a42fb2613bf9a;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git
x86_64: prepare shared kernel/vsyscall.c
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
diff --git a/arch/x86_64/kernel/Makefile b/arch/x86_64/kernel/Makefile
index 14316a259aea..a5ff38d5097c 100644
--- a/arch/x86_64/kernel/Makefile
+++ b/arch/x86_64/kernel/Makefile
@@ -6,7 +6,7 @@ extra-y := head.o head64.o init_task.o vmlinux.lds
EXTRA_AFLAGS := -traditional
obj-y := process.o signal.o entry.o traps_64.o irq.o \
ptrace.o time.o ioport.o ldt.o setup_64.o i8259_64.o sys_x86_64.o \
- x8664_ksyms.o i387.o syscall.o vsyscall.o \
+ x8664_ksyms.o i387.o syscall.o vsyscall_64.o \
setup64.o bootflag.o e820_64.o reboot.o quirks.o i8237.o \
pci-dma_64.o pci-nommu.o alternative.o hpet_64.o tsc.o bugs.o \
perfctr-watchdog.o
@@ -46,7 +46,7 @@ obj-y += intel_cacheinfo.o
obj-y += addon_cpuid_features.o
obj-y += pcspeaker.o
-CFLAGS_vsyscall.o := $(PROFILING) -g0
+CFLAGS_vsyscall_64.o := $(PROFILING) -g0
therm_throt-y += ../../i386/kernel/cpu/mcheck/therm_throt.o
bootflag-y += ../../i386/kernel/bootflag.o
diff --git a/arch/x86_64/kernel/vsyscall.c b/arch/x86_64/kernel/vsyscall.c
deleted file mode 100644
index 06c34949bfdc..000000000000
--- a/arch/x86_64/kernel/vsyscall.c
+++ /dev/null
@@ -1,349 +0,0 @@
-/*
- * linux/arch/x86_64/kernel/vsyscall.c
- *
- * Copyright (C) 2001 Andrea Arcangeli <andrea@suse.de> SuSE
- * Copyright 2003 Andi Kleen, SuSE Labs.
- *
- * Thanks to hpa@transmeta.com for some useful hint.
- * Special thanks to Ingo Molnar for his early experience with
- * a different vsyscall implementation for Linux/IA32 and for the name.
- *
- * vsyscall 1 is located at -10Mbyte, vsyscall 2 is located
- * at virtual address -10Mbyte+1024bytes etc... There are at max 4
- * vsyscalls. One vsyscall can reserve more than 1 slot to avoid
- * jumping out of line if necessary. We cannot add more with this
- * mechanism because older kernels won't return -ENOSYS.
- * If we want more than four we need a vDSO.
- *
- * Note: the concept clashes with user mode linux. If you use UML and
- * want per guest time just set the kernel.vsyscall64 sysctl to 0.
- */
-
-#include <linux/time.h>
-#include <linux/init.h>
-#include <linux/kernel.h>
-#include <linux/timer.h>
-#include <linux/seqlock.h>
-#include <linux/jiffies.h>
-#include <linux/sysctl.h>
-#include <linux/clocksource.h>
-#include <linux/getcpu.h>
-#include <linux/cpu.h>
-#include <linux/smp.h>
-#include <linux/notifier.h>
-
-#include <asm/vsyscall.h>
-#include <asm/pgtable.h>
-#include <asm/page.h>
-#include <asm/unistd.h>
-#include <asm/fixmap.h>
-#include <asm/errno.h>
-#include <asm/io.h>
-#include <asm/segment.h>
-#include <asm/desc.h>
-#include <asm/topology.h>
-#include <asm/vgtod.h>
-
-#define __vsyscall(nr) __attribute__ ((unused,__section__(".vsyscall_" #nr)))
-#define __syscall_clobber "r11","rcx","memory"
-#define __pa_vsymbol(x) \
- ({unsigned long v; \
- extern char __vsyscall_0; \
- asm("" : "=r" (v) : "0" (x)); \
- ((v - VSYSCALL_FIRST_PAGE) + __pa_symbol(&__vsyscall_0)); })
-
-/*
- * vsyscall_gtod_data contains data that is :
- * - readonly from vsyscalls
- * - writen by timer interrupt or systcl (/proc/sys/kernel/vsyscall64)
- * Try to keep this structure as small as possible to avoid cache line ping pongs
- */
-int __vgetcpu_mode __section_vgetcpu_mode;
-
-struct vsyscall_gtod_data __vsyscall_gtod_data __section_vsyscall_gtod_data =
-{
- .lock = SEQLOCK_UNLOCKED,
- .sysctl_enabled = 1,
-};
-
-void update_vsyscall(struct timespec *wall_time, struct clocksource *clock)
-{
- unsigned long flags;
-
- write_seqlock_irqsave(&vsyscall_gtod_data.lock, flags);
- /* copy vsyscall data */
- vsyscall_gtod_data.clock.vread = clock->vread;
- vsyscall_gtod_data.clock.cycle_last = clock->cycle_last;
- vsyscall_gtod_data.clock.mask = clock->mask;
- vsyscall_gtod_data.clock.mult = clock->mult;
- vsyscall_gtod_data.clock.shift = clock->shift;
- vsyscall_gtod_data.wall_time_sec = wall_time->tv_sec;
- vsyscall_gtod_data.wall_time_nsec = wall_time->tv_nsec;
- vsyscall_gtod_data.sys_tz = sys_tz;
- vsyscall_gtod_data.wall_time_nsec = wall_time->tv_nsec;
- vsyscall_gtod_data.wall_to_monotonic = wall_to_monotonic;
- write_sequnlock_irqrestore(&vsyscall_gtod_data.lock, flags);
-}
-
-/* RED-PEN may want to readd seq locking, but then the variable should be
- * write-once.
- */
-static __always_inline void do_get_tz(struct timezone * tz)
-{
- *tz = __vsyscall_gtod_data.sys_tz;
-}
-
-static __always_inline int gettimeofday(struct timeval *tv, struct timezone *tz)
-{
- int ret;
- asm volatile("vsysc2: syscall"
- : "=a" (ret)
- : "0" (__NR_gettimeofday),"D" (tv),"S" (tz)
- : __syscall_clobber );
- return ret;
-}
-
-static __always_inline long time_syscall(long *t)
-{
- long secs;
- asm volatile("vsysc1: syscall"
- : "=a" (secs)
- : "0" (__NR_time),"D" (t) : __syscall_clobber);
- return secs;
-}
-
-static __always_inline void do_vgettimeofday(struct timeval * tv)
-{
- cycle_t now, base, mask, cycle_delta;
- unsigned seq;
- unsigned long mult, shift, nsec;
- cycle_t (*vread)(void);
- do {
- seq = read_seqbegin(&__vsyscall_gtod_data.lock);
-
- vread = __vsyscall_gtod_data.clock.vread;
- if (unlikely(!__vsyscall_gtod_data.sysctl_enabled || !vread)) {
- gettimeofday(tv,NULL);
- return;
- }
- now = vread();
- base = __vsyscall_gtod_data.clock.cycle_last;
- mask = __vsyscall_gtod_data.clock.mask;
- mult = __vsyscall_gtod_data.clock.mult;
- shift = __vsyscall_gtod_data.clock.shift;
-
- tv->tv_sec = __vsyscall_gtod_data.wall_time_sec;
- nsec = __vsyscall_gtod_data.wall_time_nsec;
- } while (read_seqretry(&__vsyscall_gtod_data.lock, seq));
-
- /* calculate interval: */
- cycle_delta = (now - base) & mask;
- /* convert to nsecs: */
- nsec += (cycle_delta * mult) >> shift;
-
- while (nsec >= NSEC_PER_SEC) {
- tv->tv_sec += 1;
- nsec -= NSEC_PER_SEC;
- }
- tv->tv_usec = nsec / NSEC_PER_USEC;
-}
-
-int __vsyscall(0) vgettimeofday(struct timeval * tv, struct timezone * tz)
-{
- if (tv)
- do_vgettimeofday(tv);
- if (tz)
- do_get_tz(tz);
- return 0;
-}
-
-/* This will break when the xtime seconds get inaccurate, but that is
- * unlikely */
-time_t __vsyscall(1) vtime(time_t *t)
-{
- struct timeval tv;
- time_t result;
- if (unlikely(!__vsyscall_gtod_data.sysctl_enabled))
- return time_syscall(t);
-
- vgettimeofday(&tv, 0);
- result = tv.tv_sec;
- if (t)
- *t = result;
- return result;
-}
-
-/* Fast way to get current CPU and node.
- This helps to do per node and per CPU caches in user space.
- The result is not guaranteed without CPU affinity, but usually
- works out because the scheduler tries to keep a thread on the same
- CPU.
-
- tcache must point to a two element sized long array.
- All arguments can be NULL. */
-long __vsyscall(2)
-vgetcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *tcache)
-{
- unsigned int dummy, p;
- unsigned long j = 0;
-
- /* Fast cache - only recompute value once per jiffies and avoid
- relatively costly rdtscp/cpuid otherwise.
- This works because the scheduler usually keeps the process
- on the same CPU and this syscall doesn't guarantee its
- results anyways.
- We do this here because otherwise user space would do it on
- its own in a likely inferior way (no access to jiffies).
- If you don't like it pass NULL. */
- if (tcache && tcache->blob[0] == (j = __jiffies)) {
- p = tcache->blob[1];
- } else if (__vgetcpu_mode == VGETCPU_RDTSCP) {
- /* Load per CPU data from RDTSCP */
- rdtscp(dummy, dummy, p);
- } else {
- /* Load per CPU data from GDT */
- asm("lsl %1,%0" : "=r" (p) : "r" (__PER_CPU_SEG));
- }
- if (tcache) {
- tcache->blob[0] = j;
- tcache->blob[1] = p;
- }
- if (cpu)
- *cpu = p & 0xfff;
- if (node)
- *node = p >> 12;
- return 0;
-}
-
-long __vsyscall(3) venosys_1(void)
-{
- return -ENOSYS;
-}
-
-#ifdef CONFIG_SYSCTL
-
-#define SYSCALL 0x050f
-#define NOP2 0x9090
-
-/*
- * NOP out syscall in vsyscall page when not needed.
- */
-static int vsyscall_sysctl_change(ctl_table *ctl, int write, struct file * filp,
- void __user *buffer, size_t *lenp, loff_t *ppos)
-{
- extern u16 vsysc1, vsysc2;
- u16 __iomem *map1;
- u16 __iomem *map2;
- int ret = proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
- if (!write)
- return ret;
- /* gcc has some trouble with __va(__pa()), so just do it this
- way. */
- map1 = ioremap(__pa_vsymbol(&vsysc1), 2);
- if (!map1)
- return -ENOMEM;
- map2 = ioremap(__pa_vsymbol(&vsysc2), 2);
- if (!map2) {
- ret = -ENOMEM;
- goto out;
- }
- if (!vsyscall_gtod_data.sysctl_enabled) {
- writew(SYSCALL, map1);
- writew(SYSCALL, map2);
- } else {
- writew(NOP2, map1);
- writew(NOP2, map2);
- }
- iounmap(map2);
-out:
- iounmap(map1);
- return ret;
-}
-
-static int vsyscall_sysctl_nostrat(ctl_table *t, int __user *name, int nlen,
- void __user *oldval, size_t __user *oldlenp,
- void __user *newval, size_t newlen)
-{
- return -ENOSYS;
-}
-
-static ctl_table kernel_table2[] = {
- { .ctl_name = 99, .procname = "vsyscall64",
- .data = &vsyscall_gtod_data.sysctl_enabled, .maxlen = sizeof(int),
- .mode = 0644,
- .strategy = vsyscall_sysctl_nostrat,
- .proc_handler = vsyscall_sysctl_change },
- {}
-};
-
-static ctl_table kernel_root_table2[] = {
- { .ctl_name = CTL_KERN, .procname = "kernel", .mode = 0555,
- .child = kernel_table2 },
- {}
-};
-
-#endif
-
-/* Assume __initcall executes before all user space. Hopefully kmod
- doesn't violate that. We'll find out if it does. */
-static void __cpuinit vsyscall_set_cpu(int cpu)
-{
- unsigned long *d;
- unsigned long node = 0;
-#ifdef CONFIG_NUMA
- node = cpu_to_node[cpu];
-#endif
- if (cpu_has(&cpu_data[cpu], X86_FEATURE_RDTSCP))
- write_rdtscp_aux((node << 12) | cpu);
-
- /* Store cpu number in limit so that it can be loaded quickly
- in user space in vgetcpu.
- 12 bits for the CPU and 8 bits for the node. */
- d = (unsigned long *)(cpu_gdt(cpu) + GDT_ENTRY_PER_CPU);
- *d = 0x0f40000000000ULL;
- *d |= cpu;
- *d |= (node & 0xf) << 12;
- *d |= (node >> 4) << 48;
-}
-
-static void __cpuinit cpu_vsyscall_init(void *arg)
-{
- /* preemption should be already off */
- vsyscall_set_cpu(raw_smp_processor_id());
-}
-
-static int __cpuinit
-cpu_vsyscall_notifier(struct notifier_block *n, unsigned long action, void *arg)
-{
- long cpu = (long)arg;
- if (action == CPU_ONLINE || action == CPU_ONLINE_FROZEN)
- smp_call_function_single(cpu, cpu_vsyscall_init, NULL, 0, 1);
- return NOTIFY_DONE;
-}
-
-static void __init map_vsyscall(void)
-{
- extern char __vsyscall_0;
- unsigned long physaddr_page0 = __pa_symbol(&__vsyscall_0);
-
- /* Note that VSYSCALL_MAPPED_PAGES must agree with the code below. */
- __set_fixmap(VSYSCALL_FIRST_PAGE, physaddr_page0, PAGE_KERNEL_VSYSCALL);
-}
-
-static int __init vsyscall_init(void)
-{
- BUG_ON(((unsigned long) &vgettimeofday !=
- VSYSCALL_ADDR(__NR_vgettimeofday)));
- BUG_ON((unsigned long) &vtime != VSYSCALL_ADDR(__NR_vtime));
- BUG_ON((VSYSCALL_ADDR(0) != __fix_to_virt(VSYSCALL_FIRST_PAGE)));
- BUG_ON((unsigned long) &vgetcpu != VSYSCALL_ADDR(__NR_vgetcpu));
- map_vsyscall();
-#ifdef CONFIG_SYSCTL
- register_sysctl_table(kernel_root_table2);
-#endif
- on_each_cpu(cpu_vsyscall_init, NULL, 0, 1);
- hotcpu_notifier(cpu_vsyscall_notifier, 0);
- return 0;
-}
-
-__initcall(vsyscall_init);
diff --git a/arch/x86_64/kernel/vsyscall_64.c b/arch/x86_64/kernel/vsyscall_64.c
new file mode 100644
index 000000000000..06c34949bfdc
--- /dev/null
+++ b/arch/x86_64/kernel/vsyscall_64.c
@@ -0,0 +1,349 @@
+/*
+ * linux/arch/x86_64/kernel/vsyscall.c
+ *
+ * Copyright (C) 2001 Andrea Arcangeli <andrea@suse.de> SuSE
+ * Copyright 2003 Andi Kleen, SuSE Labs.
+ *
+ * Thanks to hpa@transmeta.com for some useful hint.
+ * Special thanks to Ingo Molnar for his early experience with
+ * a different vsyscall implementation for Linux/IA32 and for the name.
+ *
+ * vsyscall 1 is located at -10Mbyte, vsyscall 2 is located
+ * at virtual address -10Mbyte+1024bytes etc... There are at max 4
+ * vsyscalls. One vsyscall can reserve more than 1 slot to avoid
+ * jumping out of line if necessary. We cannot add more with this
+ * mechanism because older kernels won't return -ENOSYS.
+ * If we want more than four we need a vDSO.
+ *
+ * Note: the concept clashes with user mode linux. If you use UML and
+ * want per guest time just set the kernel.vsyscall64 sysctl to 0.
+ */
+
+#include <linux/time.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/timer.h>
+#include <linux/seqlock.h>
+#include <linux/jiffies.h>
+#include <linux/sysctl.h>
+#include <linux/clocksource.h>
+#include <linux/getcpu.h>
+#include <linux/cpu.h>
+#include <linux/smp.h>
+#include <linux/notifier.h>
+
+#include <asm/vsyscall.h>
+#include <asm/pgtable.h>
+#include <asm/page.h>
+#include <asm/unistd.h>
+#include <asm/fixmap.h>
+#include <asm/errno.h>
+#include <asm/io.h>
+#include <asm/segment.h>
+#include <asm/desc.h>
+#include <asm/topology.h>
+#include <asm/vgtod.h>
+
+#define __vsyscall(nr) __attribute__ ((unused,__section__(".vsyscall_" #nr)))
+#define __syscall_clobber "r11","rcx","memory"
+#define __pa_vsymbol(x) \
+ ({unsigned long v; \
+ extern char __vsyscall_0; \
+ asm("" : "=r" (v) : "0" (x)); \
+ ((v - VSYSCALL_FIRST_PAGE) + __pa_symbol(&__vsyscall_0)); })
+
+/*
+ * vsyscall_gtod_data contains data that is :
+ * - readonly from vsyscalls
+ * - writen by timer interrupt or systcl (/proc/sys/kernel/vsyscall64)
+ * Try to keep this structure as small as possible to avoid cache line ping pongs
+ */
+int __vgetcpu_mode __section_vgetcpu_mode;
+
+struct vsyscall_gtod_data __vsyscall_gtod_data __section_vsyscall_gtod_data =
+{
+ .lock = SEQLOCK_UNLOCKED,
+ .sysctl_enabled = 1,
+};
+
+void update_vsyscall(struct timespec *wall_time, struct clocksource *clock)
+{
+ unsigned long flags;
+
+ write_seqlock_irqsave(&vsyscall_gtod_data.lock, flags);
+ /* copy vsyscall data */
+ vsyscall_gtod_data.clock.vread = clock->vread;
+ vsyscall_gtod_data.clock.cycle_last = clock->cycle_last;
+ vsyscall_gtod_data.clock.mask = clock->mask;
+ vsyscall_gtod_data.clock.mult = clock->mult;
+ vsyscall_gtod_data.clock.shift = clock->shift;
+ vsyscall_gtod_data.wall_time_sec = wall_time->tv_sec;
+ vsyscall_gtod_data.wall_time_nsec = wall_time->tv_nsec;
+ vsyscall_gtod_data.sys_tz = sys_tz;
+ vsyscall_gtod_data.wall_time_nsec = wall_time->tv_nsec;
+ vsyscall_gtod_data.wall_to_monotonic = wall_to_monotonic;
+ write_sequnlock_irqrestore(&vsyscall_gtod_data.lock, flags);
+}
+
+/* RED-PEN may want to readd seq locking, but then the variable should be
+ * write-once.
+ */
+static __always_inline void do_get_tz(struct timezone * tz)
+{
+ *tz = __vsyscall_gtod_data.sys_tz;
+}
+
+static __always_inline int gettimeofday(struct timeval *tv, struct timezone *tz)
+{
+ int ret;
+ asm volatile("vsysc2: syscall"
+ : "=a" (ret)
+ : "0" (__NR_gettimeofday),"D" (tv),"S" (tz)
+ : __syscall_clobber );
+ return ret;
+}
+
+static __always_inline long time_syscall(long *t)
+{
+ long secs;
+ asm volatile("vsysc1: syscall"
+ : "=a" (secs)
+ : "0" (__NR_time),"D" (t) : __syscall_clobber);
+ return secs;
+}
+
+static __always_inline void do_vgettimeofday(struct timeval * tv)
+{
+ cycle_t now, base, mask, cycle_delta;
+ unsigned seq;
+ unsigned long mult, shift, nsec;
+ cycle_t (*vread)(void);
+ do {
+ seq = read_seqbegin(&__vsyscall_gtod_data.lock);
+
+ vread = __vsyscall_gtod_data.clock.vread;
+ if (unlikely(!__vsyscall_gtod_data.sysctl_enabled || !vread)) {
+ gettimeofday(tv,NULL);
+ return;
+ }
+ now = vread();
+ base = __vsyscall_gtod_data.clock.cycle_last;
+ mask = __vsyscall_gtod_data.clock.mask;
+ mult = __vsyscall_gtod_data.clock.mult;
+ shift = __vsyscall_gtod_data.clock.shift;
+
+ tv->tv_sec = __vsyscall_gtod_data.wall_time_sec;
+ nsec = __vsyscall_gtod_data.wall_time_nsec;
+ } while (read_seqretry(&__vsyscall_gtod_data.lock, seq));
+
+ /* calculate interval: */
+ cycle_delta = (now - base) & mask;
+ /* convert to nsecs: */
+ nsec += (cycle_delta * mult) >> shift;
+
+ while (nsec >= NSEC_PER_SEC) {
+ tv->tv_sec += 1;
+ nsec -= NSEC_PER_SEC;
+ }
+ tv->tv_usec = nsec / NSEC_PER_USEC;
+}
+
+int __vsyscall(0) vgettimeofday(struct timeval * tv, struct timezone * tz)
+{
+ if (tv)
+ do_vgettimeofday(tv);
+ if (tz)
+ do_get_tz(tz);
+ return 0;
+}
+
+/* This will break when the xtime seconds get inaccurate, but that is
+ * unlikely */
+time_t __vsyscall(1) vtime(time_t *t)
+{
+ struct timeval tv;
+ time_t result;
+ if (unlikely(!__vsyscall_gtod_data.sysctl_enabled))
+ return time_syscall(t);
+
+ vgettimeofday(&tv, 0);
+ result = tv.tv_sec;
+ if (t)
+ *t = result;
+ return result;
+}
+
+/* Fast way to get current CPU and node.
+ This helps to do per node and per CPU caches in user space.
+ The result is not guaranteed without CPU affinity, but usually
+ works out because the scheduler tries to keep a thread on the same
+ CPU.
+
+ tcache must point to a two element sized long array.
+ All arguments can be NULL. */
+long __vsyscall(2)
+vgetcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *tcache)
+{
+ unsigned int dummy, p;
+ unsigned long j = 0;
+
+ /* Fast cache - only recompute value once per jiffies and avoid
+ relatively costly rdtscp/cpuid otherwise.
+ This works because the scheduler usually keeps the process
+ on the same CPU and this syscall doesn't guarantee its
+ results anyways.
+ We do this here because otherwise user space would do it on
+ its own in a likely inferior way (no access to jiffies).
+ If you don't like it pass NULL. */
+ if (tcache && tcache->blob[0] == (j = __jiffies)) {
+ p = tcache->blob[1];
+ } else if (__vgetcpu_mode == VGETCPU_RDTSCP) {
+ /* Load per CPU data from RDTSCP */
+ rdtscp(dummy, dummy, p);
+ } else {
+ /* Load per CPU data from GDT */
+ asm("lsl %1,%0" : "=r" (p) : "r" (__PER_CPU_SEG));
+ }
+ if (tcache) {
+ tcache->blob[0] = j;
+ tcache->blob[1] = p;
+ }
+ if (cpu)
+ *cpu = p & 0xfff;
+ if (node)
+ *node = p >> 12;
+ return 0;
+}
+
+long __vsyscall(3) venosys_1(void)
+{
+ return -ENOSYS;
+}
+
+#ifdef CONFIG_SYSCTL
+
+#define SYSCALL 0x050f
+#define NOP2 0x9090
+
+/*
+ * NOP out syscall in vsyscall page when not needed.
+ */
+static int vsyscall_sysctl_change(ctl_table *ctl, int write, struct file * filp,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ extern u16 vsysc1, vsysc2;
+ u16 __iomem *map1;
+ u16 __iomem *map2;
+ int ret = proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
+ if (!write)
+ return ret;
+ /* gcc has some trouble with __va(__pa()), so just do it this
+ way. */
+ map1 = ioremap(__pa_vsymbol(&vsysc1), 2);
+ if (!map1)
+ return -ENOMEM;
+ map2 = ioremap(__pa_vsymbol(&vsysc2), 2);
+ if (!map2) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ if (!vsyscall_gtod_data.sysctl_enabled) {
+ writew(SYSCALL, map1);
+ writew(SYSCALL, map2);
+ } else {
+ writew(NOP2, map1);
+ writew(NOP2, map2);
+ }
+ iounmap(map2);
+out:
+ iounmap(map1);
+ return ret;
+}
+
+static int vsyscall_sysctl_nostrat(ctl_table *t, int __user *name, int nlen,
+ void __user *oldval, size_t __user *oldlenp,
+ void __user *newval, size_t newlen)
+{
+ return -ENOSYS;
+}
+
+static ctl_table kernel_table2[] = {
+ { .ctl_name = 99, .procname = "vsyscall64",
+ .data = &vsyscall_gtod_data.sysctl_enabled, .maxlen = sizeof(int),
+ .mode = 0644,
+ .strategy = vsyscall_sysctl_nostrat,
+ .proc_handler = vsyscall_sysctl_change },
+ {}
+};
+
+static ctl_table kernel_root_table2[] = {
+ { .ctl_name = CTL_KERN, .procname = "kernel", .mode = 0555,
+ .child = kernel_table2 },
+ {}
+};
+
+#endif
+
+/* Assume __initcall executes before all user space. Hopefully kmod
+ doesn't violate that. We'll find out if it does. */
+static void __cpuinit vsyscall_set_cpu(int cpu)
+{
+ unsigned long *d;
+ unsigned long node = 0;
+#ifdef CONFIG_NUMA
+ node = cpu_to_node[cpu];
+#endif
+ if (cpu_has(&cpu_data[cpu], X86_FEATURE_RDTSCP))
+ write_rdtscp_aux((node << 12) | cpu);
+
+ /* Store cpu number in limit so that it can be loaded quickly
+ in user space in vgetcpu.
+ 12 bits for the CPU and 8 bits for the node. */
+ d = (unsigned long *)(cpu_gdt(cpu) + GDT_ENTRY_PER_CPU);
+ *d = 0x0f40000000000ULL;
+ *d |= cpu;
+ *d |= (node & 0xf) << 12;
+ *d |= (node >> 4) << 48;
+}
+
+static void __cpuinit cpu_vsyscall_init(void *arg)
+{
+ /* preemption should be already off */
+ vsyscall_set_cpu(raw_smp_processor_id());
+}
+
+static int __cpuinit
+cpu_vsyscall_notifier(struct notifier_block *n, unsigned long action, void *arg)
+{
+ long cpu = (long)arg;
+ if (action == CPU_ONLINE || action == CPU_ONLINE_FROZEN)
+ smp_call_function_single(cpu, cpu_vsyscall_init, NULL, 0, 1);
+ return NOTIFY_DONE;
+}
+
+static void __init map_vsyscall(void)
+{
+ extern char __vsyscall_0;
+ unsigned long physaddr_page0 = __pa_symbol(&__vsyscall_0);
+
+ /* Note that VSYSCALL_MAPPED_PAGES must agree with the code below. */
+ __set_fixmap(VSYSCALL_FIRST_PAGE, physaddr_page0, PAGE_KERNEL_VSYSCALL);
+}
+
+static int __init vsyscall_init(void)
+{
+ BUG_ON(((unsigned long) &vgettimeofday !=
+ VSYSCALL_ADDR(__NR_vgettimeofday)));
+ BUG_ON((unsigned long) &vtime != VSYSCALL_ADDR(__NR_vtime));
+ BUG_ON((VSYSCALL_ADDR(0) != __fix_to_virt(VSYSCALL_FIRST_PAGE)));
+ BUG_ON((unsigned long) &vgetcpu != VSYSCALL_ADDR(__NR_vgetcpu));
+ map_vsyscall();
+#ifdef CONFIG_SYSCTL
+ register_sysctl_table(kernel_root_table2);
+#endif
+ on_each_cpu(cpu_vsyscall_init, NULL, 0, 1);
+ hotcpu_notifier(cpu_vsyscall_notifier, 0);
+ return 0;
+}
+
+__initcall(vsyscall_init);