Merge ../linux-2.6-watchdog-mm

[pandora-kernel.git] / arch / i386 / kernel / apm.c

diff --git a/arch/i386/kernel/apm.c b/arch/i386/kernel/apm.c
index ff9ce4b..1990169 100644 (file)
--- a/arch/i386/kernel/apm.c
+++ b/arch/i386/kernel/apm.c
@@ -198,7 +198,7 @@
  *   (APM) BIOS Interface Specification, Revision 1.2, February 1996.
  *
  * [This document is available from Microsoft at:
- *    http://www.microsoft.com/hwdev/busbios/amp_12.htm]
+ *    http://www.microsoft.com/whdc/archive/amp_12.mspx]
  */
 
 #include <linux/module.h>
@@ -225,11 +225,13 @@
 #include <linux/smp_lock.h>
 #include <linux/dmi.h>
 #include <linux/suspend.h>
+#include <linux/kthread.h>
 
 #include <asm/system.h>
 #include <asm/uaccess.h>
 #include <asm/desc.h>
 #include <asm/i8253.h>
+#include <asm/paravirt.h>
 
 #include "io_ports.h"
 
@@ -402,8 +404,6 @@ static int                  realmode_power_off = 1;
 #else
 static int                     realmode_power_off;
 #endif
-static int                     exit_kapmd __read_mostly;
-static int                     kapmd_running __read_mostly;
 #ifdef CONFIG_APM_ALLOW_INTS
 static int                     allow_ints = 1;
 #else
@@ -419,6 +419,8 @@ static const struct desc_struct     bad_bios_desc = { 0, 0x00409200 };
 
 static const char              driver_version[] = "1.16ac";    /* no spaces */
 
+static struct task_struct *kapmd_task;
+
 /*
  *     APM event names taken from the APM 1.2 specification. These are
  *     the message codes that the BIOS uses to tell us about events
@@ -539,11 +541,30 @@ static inline void apm_restore_cpus(cpumask_t mask)
  * Also, we KNOW that for the non error case of apm_bios_call, there
  * is no useful data returned in the low order 8 bits of eax.
  */
-#define APM_DO_CLI     \
-       if (apm_info.allow_ints) \
-               local_irq_enable(); \
-       else \
+
+static inline unsigned long __apm_irq_save(void)
+{
+       unsigned long flags;
+       local_save_flags(flags);
+       if (apm_info.allow_ints) {
+               if (irqs_disabled_flags(flags))
+                       local_irq_enable();
+       } else
+               local_irq_disable();
+
+       return flags;
+}
+
+#define apm_irq_save(flags) \
+       do { flags = __apm_irq_save(); } while (0)
+
+static inline void apm_irq_restore(unsigned long flags)
+{
+       if (irqs_disabled_flags(flags))
                local_irq_disable();
+       else if (irqs_disabled())
+               local_irq_enable();
+}
 
 #ifdef APM_ZERO_SEGS
 #      define APM_DECL_SEGS \
@@ -595,12 +616,11 @@ static u8 apm_bios_call(u32 func, u32 ebx_in, u32 ecx_in,
        save_desc_40 = gdt[0x40 / 8];
        gdt[0x40 / 8] = bad_bios_desc;
 
-       local_save_flags(flags);
-       APM_DO_CLI;
+       apm_irq_save(flags);
        APM_DO_SAVE_SEGS;
        apm_bios_call_asm(func, ebx_in, ecx_in, eax, ebx, ecx, edx, esi);
        APM_DO_RESTORE_SEGS;
-       local_irq_restore(flags);
+       apm_irq_restore(flags);
        gdt[0x40 / 8] = save_desc_40;
        put_cpu();
        apm_restore_cpus(cpus);
@@ -639,12 +659,11 @@ static u8 apm_bios_call_simple(u32 func, u32 ebx_in, u32 ecx_in, u32 *eax)
        save_desc_40 = gdt[0x40 / 8];
        gdt[0x40 / 8] = bad_bios_desc;
 
-       local_save_flags(flags);
-       APM_DO_CLI;
+       apm_irq_save(flags);
        APM_DO_SAVE_SEGS;
        error = apm_bios_call_simple_asm(func, ebx_in, ecx_in, eax);
        APM_DO_RESTORE_SEGS;
-       local_irq_restore(flags);
+       apm_irq_restore(flags);
        gdt[0x40 / 8] = save_desc_40;
        put_cpu();
        apm_restore_cpus(cpus);
@@ -766,7 +785,11 @@ static int apm_do_idle(void)
        polling = !!(current_thread_info()->status & TS_POLLING);
        if (polling) {
                current_thread_info()->status &= ~TS_POLLING;
-               smp_mb__after_clear_bit();
+               /*
+                * TS_POLLING-cleared state must be visible before we
+                * test NEED_RESCHED:
+                */
+               smp_mb();
        }
        if (!need_resched()) {
                idled = 1;
@@ -1423,7 +1446,7 @@ static void apm_mainloop(void)
        set_current_state(TASK_INTERRUPTIBLE);
        for (;;) {
                schedule_timeout(APM_CHECK_TIMEOUT);
-               if (exit_kapmd)
+               if (kthread_should_stop())
                        break;
                /*
                 * Ok, check all events, check for idle (and mark us sleeping
@@ -1585,7 +1608,7 @@ static int do_open(struct inode * inode, struct file * filp)
 {
        struct apm_user *       as;
 
-       as = (struct apm_user *)kmalloc(sizeof(*as), GFP_KERNEL);
+       as = kmalloc(sizeof(*as), GFP_KERNEL);
        if (as == NULL) {
                printk(KERN_ERR "apm: cannot allocate struct of size %d bytes\n",
                       sizeof(*as));
@@ -1706,12 +1729,6 @@ static int apm(void *unused)
        char *          power_stat;
        char *          bat_stat;
 
-       kapmd_running = 1;
-
-       daemonize("kapmd");
-
-       current->flags |= PF_NOFREEZE;
-
 #ifdef CONFIG_SMP
        /* 2002/08/01 - WT
         * This is to avoid random crashes at boot time during initialization
@@ -1821,7 +1838,6 @@ static int apm(void *unused)
                console_blank_hook = NULL;
 #endif
        }
-       kapmd_running = 0;
 
        return 0;
 }
@@ -2220,11 +2236,11 @@ static int __init apm_init(void)
 {
        struct proc_dir_entry *apm_proc;
        struct desc_struct *gdt;
-       int ret;
+       int err;
 
        dmi_check_system(apm_dmi_table);
 
-       if (apm_info.bios.version == 0) {
+       if (apm_info.bios.version == 0 || paravirt_enabled()) {
                printk(KERN_INFO "apm: BIOS not found.\n");
                return -ENODEV;
        }
@@ -2329,12 +2345,17 @@ static int __init apm_init(void)
        if (apm_proc)
                apm_proc->owner = THIS_MODULE;
 
-       ret = kernel_thread(apm, NULL, CLONE_KERNEL | SIGCHLD);
-       if (ret < 0) {
-               printk(KERN_ERR "apm: disabled - Unable to start kernel thread.\n");
+       kapmd_task = kthread_create(apm, NULL, "kapmd");
+       if (IS_ERR(kapmd_task)) {
+               printk(KERN_ERR "apm: disabled - Unable to start kernel "
+                               "thread.\n");
+               err = PTR_ERR(kapmd_task);
+               kapmd_task = NULL;
                remove_proc_entry("apm", NULL);
-               return -ENOMEM;
+               return err;
        }
+       kapmd_task->flags |= PF_NOFREEZE;
+       wake_up_process(kapmd_task);
 
        if (num_online_cpus() > 1 && !smp ) {
                printk(KERN_NOTICE
@@ -2384,9 +2405,10 @@ static void __exit apm_exit(void)
        remove_proc_entry("apm", NULL);
        if (power_off)
                pm_power_off = NULL;
-       exit_kapmd = 1;
-       while (kapmd_running)
-               schedule();
+       if (kapmd_task) {
+               kthread_stop(kapmd_task);
+               kapmd_task = NULL;
+       }
 #ifdef CONFIG_PM_LEGACY
        pm_active = 0;
 #endif