x86: fix vsyscall wreckage

[sfrench/cifs-2.6.git] / arch / x86 / kernel / vsyscall_64.c

diff --git a/arch/x86/kernel/vsyscall_64.c b/arch/x86/kernel/vsyscall_64.c
index 93847d848157b6bd8b14d3314d342fb889aca543..b6be812fac0502cd2caccc19dcec0a147a0dc3fa 100644 (file)
--- a/arch/x86/kernel/vsyscall_64.c
+++ b/arch/x86/kernel/vsyscall_64.c
@@ -43,17 +43,12 @@
 #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 __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;
@@ -64,6 +59,16 @@ struct vsyscall_gtod_data __vsyscall_gtod_data __section_vsyscall_gtod_data =
        .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;
@@ -77,8 +82,6 @@ void update_vsyscall(struct timespec *wall_time, struct clocksource *clock)
        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);
 }
@@ -94,7 +97,7 @@ static __always_inline void do_get_tz(struct timezone * tz)
 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 );
@@ -104,7 +107,7 @@ static __always_inline int gettimeofday(struct timeval *tv, struct timezone *tz)
 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;
@@ -164,7 +167,7 @@ time_t __vsyscall(1) vtime(time_t *t)
        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;
@@ -182,7 +185,7 @@ time_t __vsyscall(1) vtime(time_t *t)
 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
@@ -197,7 +200,7 @@ vgetcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *tcache)
                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));
@@ -219,58 +222,10 @@ long __vsyscall(3) venosys_1(void)
 }
 
 #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",
+       { .procname = "vsyscall64",
          .data = &vsyscall_gtod_data.sysctl_enabled, .maxlen = sizeof(int),
-         .mode = 0644,
-         .strategy = vsyscall_sysctl_nostrat,
-         .proc_handler = vsyscall_sysctl_change },
+         .mode = 0644 },
        {}
 };
 
@@ -279,7 +234,6 @@ static ctl_table kernel_root_table2[] = {
          .child = kernel_table2 },
        {}
 };
-
 #endif
 
 /* Assume __initcall executes before all user space. Hopefully kmod
@@ -289,15 +243,15 @@ static void __cpuinit vsyscall_set_cpu(int cpu)
        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 = (unsigned long *)(get_cpu_gdt_table(cpu) + GDT_ENTRY_PER_CPU);
        *d = 0x0f40000000000ULL;
        *d |= cpu;
        *d |= (node & 0xf) << 12;
@@ -319,7 +273,7 @@ cpu_vsyscall_notifier(struct notifier_block *n, unsigned long action, void *arg)
        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);
@@ -335,7 +289,6 @@ static int __init vsyscall_init(void)
        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