[PATCH] uml: move libc-dependent time code

The serial UML OS-abstraction layer patch (um/kernel dir).

This moves all systemcalls from time.c file under os-Linux dir and joins
time.c and tine_kernel.c files

Signed-off-by: Gennady Sharapov <Gennady.V.Sharapov@intel.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 76 insertions, 48 deletions

diff --git a/arch/um/kernel/time_kern.c b/arch/um/kernel/time_kern.c
index 020ca79b8d33..6712ffad0242 100644
--- a/arch/um/kernel/time_kern.c
+++ b/arch/um/kernel/time_kern.c
@@ -1,4 +1,4 @@
-/* 
+/*
  * Copyright (C) 2000 Jeff Dike (jdike@karaya.com)
  * Licensed under the GPL
  */
@@ -13,12 +13,12 @@
 #include "linux/interrupt.h"
 #include "linux/init.h"
 #include "linux/delay.h"
+#include "linux/hrtimer.h"
 #include "asm/irq.h"
 #include "asm/param.h"
 #include "asm/current.h"
 #include "kern_util.h"
 #include "user_util.h"
-#include "time_user.h"
 #include "mode.h"
 #include "os.h"
 
@@ -39,7 +39,7 @@ unsigned long long sched_clock(void)
 int timer_irq_inited = 0;
 
 static int first_tick;
-static unsigned long long prev_usecs;
+static unsigned long long prev_nsecs;
 #ifdef CONFIG_UML_REAL_TIME_CLOCK
 static long long delta;                 /* Deviation per interval */
 #endif
@@ -58,23 +58,23 @@ void timer_irq(union uml_pt_regs *regs)
         if(first_tick){
 #ifdef CONFIG_UML_REAL_TIME_CLOCK
                 /* We've had 1 tick */
-                unsigned long long usecs = os_usecs();
+                unsigned long long nsecs = os_nsecs();
 
-                delta += usecs - prev_usecs;
-                prev_usecs = usecs;
+                delta += nsecs - prev_nsecs;
+                prev_nsecs = nsecs;
 
                 /* Protect against the host clock being set backwards */
                 if(delta < 0)
                         delta = 0;
 
-                ticks += (delta * HZ) / MILLION;
-                delta -= (ticks * MILLION) / HZ;
+                ticks += (delta * HZ) / BILLION;
+                delta -= (ticks * BILLION) / HZ;
 #else
                 ticks = 1;
 #endif
         }
         else {
-                prev_usecs = os_usecs();
+                prev_nsecs = os_nsecs();
                 first_tick = 1;
         }
 
@@ -88,45 +88,99 @@ void boot_timer_handler(int sig)
 {
         struct pt_regs regs;
 
-        CHOOSE_MODE((void) 
+        CHOOSE_MODE((void)
                     (UPT_SC(&regs.regs) = (struct sigcontext *) (&sig + 1)),
                     (void) (regs.regs.skas.is_user = 0));
         do_timer(&regs);
 }
 
+static DEFINE_SPINLOCK(timer_spinlock);
+
+static unsigned long long local_offset = 0;
+
+static inline unsigned long long get_time(void)
+{
+        unsigned long long nsecs;
+        unsigned long flags;
+
+        spin_lock_irqsave(&timer_spinlock, flags);
+        nsecs = os_nsecs();
+        nsecs += local_offset;
+        spin_unlock_irqrestore(&timer_spinlock, flags);
+
+        return nsecs;
+}
+
 irqreturn_t um_timer(int irq, void *dev, struct pt_regs *regs)
 {
+        unsigned long long nsecs;
         unsigned long flags;
 
         do_timer(regs);
+
         write_seqlock_irqsave(&xtime_lock, flags);
-        timer();
+        nsecs = get_time() + local_offset;
+        xtime.tv_sec = nsecs / NSEC_PER_SEC;
+        xtime.tv_nsec = nsecs - xtime.tv_sec * NSEC_PER_SEC;
         write_sequnlock_irqrestore(&xtime_lock, flags);
+
         return(IRQ_HANDLED);
 }
 
 long um_time(int __user *tloc)
 {
-        struct timeval now;
+        long ret = get_time() / NSEC_PER_SEC;
 
-        do_gettimeofday(&now);
-        if (tloc) {
-                if (put_user(now.tv_sec, tloc))
-                        now.tv_sec = -EFAULT;
-        }
-        return now.tv_sec;
+        if((tloc != NULL) && put_user(ret, tloc))
+                return -EFAULT;
+
+        return ret;
+}
+
+void do_gettimeofday(struct timeval *tv)
+{
+        unsigned long long nsecs = get_time();
+
+        tv->tv_sec = nsecs / NSEC_PER_SEC;
+        /* Careful about calculations here - this was originally done as
+         * (nsecs - tv->tv_sec * NSEC_PER_SEC) / NSEC_PER_USEC
+         * which gave bogus (> 1000000) values.  Dunno why, suspect gcc
+         * (4.0.0) miscompiled it, or there's a subtle 64/32-bit conversion
+         * problem that I missed.
+         */
+        nsecs -= tv->tv_sec * NSEC_PER_SEC;
+        tv->tv_usec = (unsigned long) nsecs / NSEC_PER_USEC;
+}
+
+static inline void set_time(unsigned long long nsecs)
+{
+        unsigned long long now;
+        unsigned long flags;
+
+        spin_lock_irqsave(&timer_spinlock, flags);
+        now = os_nsecs();
+        local_offset = nsecs - now;
+        spin_unlock_irqrestore(&timer_spinlock, flags);
+
+        clock_was_set();
 }
 
 long um_stime(int __user *tptr)
 {
         int value;
-        struct timespec new;
 
         if (get_user(value, tptr))
                 return -EFAULT;
-        new.tv_sec = value;
-        new.tv_nsec = 0;
-        do_settimeofday(&new);
+
+        set_time((unsigned long long) value * NSEC_PER_SEC);
+
+        return 0;
+}
+
+int do_settimeofday(struct timespec *tv)
+{
+        set_time((unsigned long long) tv->tv_sec * NSEC_PER_SEC + tv->tv_nsec);
+
         return 0;
 }
 
@@ -142,21 +196,6 @@ void timer_handler(int sig, union uml_pt_regs *regs)
                 timer_irq(regs);
 }
 
-static DEFINE_SPINLOCK(timer_spinlock);
-
-unsigned long time_lock(void)
-{
-        unsigned long flags;
-
-        spin_lock_irqsave(&timer_spinlock, flags);
-        return(flags);
-}
-
-void time_unlock(unsigned long flags)
-{
-        spin_unlock_irqrestore(&timer_spinlock, flags);
-}
-
 int __init timer_init(void)
 {
         int err;
@@ -171,14 +210,3 @@ int __init timer_init(void)
 }
 
 __initcall(timer_init);
-
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-file-style: "linux"
- * End:
- */