/*
- * linux/arch/x86_64/kernel/vsyscall.c
- *
* Copyright (C) 2001 Andrea Arcangeli <andrea@suse.de> SuSE
* Copyright 2003 Andi Kleen, SuSE Labs.
*
* want per guest time just set the kernel.vsyscall64 sysctl to 0.
*/
+/* Protect userspace from profiling */
+#ifdef CONFIG_TRACE_UNLIKELY_PROFILE
+# undef likely
+# undef unlikely
+# define likely(x) likely_notrace(x)
+# define unlikely(x) unlikely_notrace(x)
+#endif
+
#include <linux/time.h>
#include <linux/init.h>
#include <linux/kernel.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)); })
+#define __vsyscall(nr) \
+ __attribute__ ((unused, __section__(".vsyscall_" #nr))) notrace
+#define __syscall_clobber "r11","cx","memory"
/*
* vsyscall_gtod_data contains data that is :
* - readonly from vsyscalls
- * - writen by timer interrupt or systcl (/proc/sys/kernel/vsyscall64)
+ * - written 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;
.sysctl_enabled = 1,
};
+void update_vsyscall_tz(void)
+{
+ unsigned long flags;
+
+ write_seqlock_irqsave(&vsyscall_gtod_data.lock, flags);
+ /* sys_tz has changed */
+ vsyscall_gtod_data.sys_tz = sys_tz;
+ write_sequnlock_irqrestore(&vsyscall_gtod_data.lock, flags);
+}
+
void update_vsyscall(struct timespec *wall_time, struct clocksource *clock)
{
unsigned long flags;
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);
}
static __always_inline int gettimeofday(struct timeval *tv, struct timezone *tz)
{
int ret;
- asm volatile("vsysc2: syscall"
+ asm volatile("syscall"
: "=a" (ret)
: "0" (__NR_gettimeofday),"D" (tv),"S" (tz)
: __syscall_clobber );
static __always_inline long time_syscall(long *t)
{
long secs;
- asm volatile("vsysc1: syscall"
+ asm volatile("syscall"
: "=a" (secs)
: "0" (__NR_time),"D" (t) : __syscall_clobber);
return secs;
if (unlikely(!__vsyscall_gtod_data.sysctl_enabled))
return time_syscall(t);
- vgettimeofday(&tv, 0);
+ vgettimeofday(&tv, NULL);
result = tv.tv_sec;
if (t)
*t = result;
long __vsyscall(2)
vgetcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *tcache)
{
- unsigned int dummy, p;
+ unsigned int p;
unsigned long j = 0;
/* Fast cache - only recompute value once per jiffies and avoid
p = tcache->blob[1];
} else if (__vgetcpu_mode == VGETCPU_RDTSCP) {
/* Load per CPU data from RDTSCP */
- rdtscp(dummy, dummy, p);
+ native_read_tscp(&p);
} else {
/* Load per CPU data from GDT */
asm("lsl %1,%0" : "=r" (p) : "r" (__PER_CPU_SEG));
return 0;
}
-long __vsyscall(3) venosys_1(void)
+static 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)
+static int
+vsyscall_sysctl_change(ctl_table *ctl, int write, struct file * filp,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
{
- return -ENOSYS;
+ return proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
}
static ctl_table kernel_table2[] = {
- { .ctl_name = 99, .procname = "vsyscall64",
+ { .procname = "vsyscall64",
.data = &vsyscall_gtod_data.sysctl_enabled, .maxlen = sizeof(int),
.mode = 0644,
- .strategy = vsyscall_sysctl_nostrat,
.proc_handler = vsyscall_sysctl_change },
{}
};
.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 d;
unsigned long node = 0;
#ifdef CONFIG_NUMA
- node = cpu_to_node[cpu];
+ node = cpu_to_node(cpu);
#endif
- if (cpu_has(&cpu_data[cpu], X86_FEATURE_RDTSCP))
+ 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;
+ d = 0x0f40000000000ULL;
+ d |= cpu;
+ d |= (node & 0xf) << 12;
+ d |= (node >> 4) << 48;
+ write_gdt_entry(get_cpu_gdt_table(cpu), GDT_ENTRY_PER_CPU, &d, DESCTYPE_S);
}
static void __cpuinit cpu_vsyscall_init(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);
+ smp_call_function_single(cpu, cpu_vsyscall_init, NULL, 1);
return NOTIFY_DONE;
}
-static void __init map_vsyscall(void)
+void __init map_vsyscall(void)
{
extern char __vsyscall_0;
unsigned long physaddr_page0 = __pa_symbol(&__vsyscall_0);
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);
+ on_each_cpu(cpu_vsyscall_init, NULL, 1);
hotcpu_notifier(cpu_vsyscall_notifier, 0);
return 0;
}