Merge branch 'for-2.6.25' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus...

[linux-2.6-omap-h63xx.git] / arch / x86 / kernel / suspend_64.c

diff --git a/arch/x86/kernel/suspend_64.c b/arch/x86/kernel/suspend_64.c
index 2e5efaaf8800ee2d402aca5b0b9bb1a00061458e..7ac7130022f1a73926a392ee2a83d1c366d29164 100644 (file)
--- a/arch/x86/kernel/suspend_64.c
+++ b/arch/x86/kernel/suspend_64.c
@@ -17,9 +17,26 @@
 /* References to section boundaries */
 extern const void __nosave_begin, __nosave_end;
 
+static void fix_processor_context(void);
+
 struct saved_context saved_context;
 
-void __save_processor_state(struct saved_context *ctxt)
+/**
+ *     __save_processor_state - save CPU registers before creating a
+ *             hibernation image and before restoring the memory state from it
+ *     @ctxt - structure to store the registers contents in
+ *
+ *     NOTE: If there is a CPU register the modification of which by the
+ *     boot kernel (ie. the kernel used for loading the hibernation image)
+ *     might affect the operations of the restored target kernel (ie. the one
+ *     saved in the hibernation image), then its contents must be saved by this
+ *     function.  In other words, if kernel A is hibernated and different
+ *     kernel B is used for loading the hibernation image into memory, the
+ *     kernel A's __save_processor_state() function must save all registers
+ *     needed by kernel A, so that it can operate correctly after the resume
+ *     regardless of what kernel B does in the meantime.
+ */
+static void __save_processor_state(struct saved_context *ctxt)
 {
        kernel_fpu_begin();
 
@@ -69,7 +86,12 @@ static void do_fpu_end(void)
        kernel_fpu_end();
 }
 
-void __restore_processor_state(struct saved_context *ctxt)
+/**
+ *     __restore_processor_state - restore the contents of CPU registers saved
+ *             by __save_processor_state()
+ *     @ctxt - structure to load the registers contents from
+ */
+static void __restore_processor_state(struct saved_context *ctxt)
 {
        /*
         * control registers
@@ -113,14 +135,19 @@ void restore_processor_state(void)
        __restore_processor_state(&saved_context);
 }
 
-void fix_processor_context(void)
+static void fix_processor_context(void)
 {
        int cpu = smp_processor_id();
        struct tss_struct *t = &per_cpu(init_tss, cpu);
 
-       set_tss_desc(cpu,t);    /* This just modifies memory; should not be necessary. But... This is necessary, because 386 hardware has concept of busy TSS or some similar stupidity. */
+       /*
+        * This just modifies memory; should not be necessary. But... This
+        * is necessary, because 386 hardware has concept of busy TSS or some
+        * similar stupidity.
+        */
+       set_tss_desc(cpu, t);
 
-       cpu_gdt(cpu)[GDT_ENTRY_TSS].type = 9;
+       get_cpu_gdt_table(cpu)[GDT_ENTRY_TSS].type = 9;
 
        syscall_init();                         /* This sets MSR_*STAR and related */
        load_TR_desc();                         /* This does ltr */
@@ -138,7 +165,6 @@ void fix_processor_context(void)
                 loaddebug(&current->thread, 6);
                 loaddebug(&current->thread, 7);
        }
-
 }
 
 #ifdef CONFIG_HIBERNATION