Re: [PATCH] [19/48] Suspend2 2.1.9.8 for 2.6.12:510-version-specific-mac.patch

From: Nigel Cunningham
Date: Wed Jul 06 2005 - 00:43:27 EST


Hi.

This patch came from Hu Gang.

Regards,

Nigel

On Wed, 2005-07-06 at 12:20, Nigel Cunningham wrote:
> diff -ruNp 520-version-specific-x86_64.patch-old/arch/x86_64/kernel/asm-offsets.c 520-version-specific-x86_64.patch-new/arch/x86_64/kernel/asm-offsets.c
> --- 520-version-specific-x86_64.patch-old/arch/x86_64/kernel/asm-offsets.c 2005-06-20 11:46:49.000000000 +1000
> +++ 520-version-specific-x86_64.patch-new/arch/x86_64/kernel/asm-offsets.c 2005-07-04 23:14:19.000000000 +1000
> @@ -62,8 +62,10 @@ int main(void)
> offsetof (struct rt_sigframe32, uc.uc_mcontext));
> BLANK();
> #endif
> +#ifdef CONFIG_PM
> DEFINE(pbe_address, offsetof(struct pbe, address));
> DEFINE(pbe_orig_address, offsetof(struct pbe, orig_address));
> DEFINE(pbe_next, offsetof(struct pbe, next));
> +#endif
> return 0;
> }
> diff -ruNp 520-version-specific-x86_64.patch-old/arch/x86_64/kernel/Makefile 520-version-specific-x86_64.patch-new/arch/x86_64/kernel/Makefile
> --- 520-version-specific-x86_64.patch-old/arch/x86_64/kernel/Makefile 2005-06-20 11:46:49.000000000 +1000
> +++ 520-version-specific-x86_64.patch-new/arch/x86_64/kernel/Makefile 2005-07-04 23:14:19.000000000 +1000
> @@ -22,6 +22,7 @@ obj-$(CONFIG_X86_IO_APIC) += io_apic.o m
> genapic.o genapic_cluster.o genapic_flat.o
> obj-$(CONFIG_PM) += suspend.o
> obj-$(CONFIG_SOFTWARE_SUSPEND) += suspend_asm.o
> +obj-$(CONFIG_SUSPEND2) += suspend2.o
> obj-$(CONFIG_CPU_FREQ) += cpufreq/
> obj-$(CONFIG_EARLY_PRINTK) += early_printk.o
> obj-$(CONFIG_GART_IOMMU) += pci-gart.o aperture.o
> diff -ruNp 520-version-specific-x86_64.patch-old/arch/x86_64/kernel/suspend.c 520-version-specific-x86_64.patch-new/arch/x86_64/kernel/suspend.c
> --- 520-version-specific-x86_64.patch-old/arch/x86_64/kernel/suspend.c 2004-11-03 21:53:44.000000000 +1100
> +++ 520-version-specific-x86_64.patch-new/arch/x86_64/kernel/suspend.c 2005-07-04 23:14:19.000000000 +1000
> @@ -26,6 +26,7 @@
> #include <asm/tlbflush.h>
> #include <asm/io.h>
> #include <asm/proto.h>
> +#include <asm/i387.h>
>
> struct saved_context saved_context;
>
> @@ -35,6 +36,8 @@ unsigned long saved_context_r08, saved_c
> unsigned long saved_context_r12, saved_context_r13, saved_context_r14, saved_context_r15;
> unsigned long saved_context_eflags;
>
> +void fix_processor_context(void);
> +
> void __save_processor_state(struct saved_context *ctxt)
> {
> kernel_fpu_begin();
> diff -ruNp 520-version-specific-x86_64.patch-old/arch/x86_64/mm/init.c 520-version-specific-x86_64.patch-new/arch/x86_64/mm/init.c
> --- 520-version-specific-x86_64.patch-old/arch/x86_64/mm/init.c 2005-06-20 11:46:49.000000000 +1000
> +++ 520-version-specific-x86_64.patch-new/arch/x86_64/mm/init.c 2005-07-04 23:14:19.000000000 +1000
> @@ -618,3 +618,22 @@ int in_gate_area_no_task(unsigned long a
> {
> return (addr >= VSYSCALL_START) && (addr < VSYSCALL_END);
> }
> +
> +#if defined(CONFIG_PM_DISK) || defined(CONFIG_SOFTWARE_SUSPEND) || defined(CONFIG_SUSPEND2)
> +/*
> + * Software suspend & friends need this for resume because things like the intel-agp
> + * driver might have split up a kernel 4MB mapping.
> + */
> +char __nosavedata swsusp_pg_dir[PAGE_SIZE]
> + __attribute__ ((aligned (PAGE_SIZE)));
> +
> +static inline void save_pg_dir(void)
> +{
> + memcpy(swsusp_pg_dir, swapper_pg_dir, PAGE_SIZE);
> +}
> +#else
> +static inline void save_pg_dir(void)
> +{
> +}
> +#endif
> +
> diff -ruNp 520-version-specific-x86_64.patch-old/include/asm-x86_64/suspend2.h 520-version-specific-x86_64.patch-new/include/asm-x86_64/suspend2.h
> --- 520-version-specific-x86_64.patch-old/include/asm-x86_64/suspend2.h 1970-01-01 10:00:00.000000000 +1000
> +++ 520-version-specific-x86_64.patch-new/include/asm-x86_64/suspend2.h 2005-07-05 23:56:15.000000000 +1000
> @@ -0,0 +1,432 @@
> + /*
> + * Copyright 2005 Nigel Cunningham <nigel@xxxxxxxxxxxx>
> + * Based on code
> + * Copyright 2001-2002 Pavel Machek <pavel@xxxxxxx>
> + * Based on code
> + * Copyright 2001 Patrick Mochel <mochel@xxxxxxxx>
> + */
> +#include <linux/irq.h>
> +#include <asm/desc.h>
> +#include <asm/i387.h>
> +#include <asm/tlbflush.h>
> +#include <asm/desc.h>
> +#include <asm/suspend.h>
> +#undef inline
> +#define inline __inline__ __attribute__((always_inline))
> +
> +/* image of the saved processor states */
> +struct suspend2_saved_context {
> + unsigned long eax, ebx, ecx, edx;
> + unsigned long esp, ebp, esi, edi;
> + unsigned long r8, r9, r10, r11;
> + unsigned long r12, r13, r14, r15;
> +
> +#if 0
> + u16 es, fs, gs, ss;
> + u32 cr0, cr2, cr3, cr4;
> + u16 gdt_pad;
> + u16 gdt_limit;
> + u32 gdt_base;
> + u16 idt_pad;
> + u16 idt_limit;
> + u32 idt_base;
> + u16 ldt;
> + u16 tss;
> + u32 tr;
> + u32 safety;
> + u32 return_address;
> +#endif
> + unsigned long eflags;
> +} __attribute__((packed));
> +
> +extern struct suspend2_saved_context suspend2_saved_context; /* temporary storage */
> +
> +#ifdef CONFIG_MTRR
> +/* MTRR functions */
> +extern int mtrr_save(void);
> +extern int mtrr_restore_one_cpu(void);
> +extern void mtrr_restore_finish(void);
> +#else
> +#define mtrr_save() do { } while(0)
> +#define mtrr_restore_one_cpu() do { } while(0)
> +#define mtrr_restore_finish() do { } while(0)
> +#endif
> +
> +#ifndef CONFIG_SMP
> +#undef cpu_clear
> +#define cpu_clear(a, b) do { } while(0)
> +#endif
> +
> +extern struct suspend2_saved_context suspend2_saved_context; /* temporary storage */
> +
> +/*
> + * save_processor_context
> + *
> + * Save the state of the processor before we go to sleep.
> + *
> + * return_stack is the value of the stack pointer (%esp) as the caller sees it.
> + * A good way could not be found to obtain it from here (don't want to make _too_
> + * many assumptions about the layout of the stack this far down.) Also, the
> + * handy little __builtin_frame_pointer(level) where level > 0, is blatantly
> + * buggy - it returns the value of the stack at the proper location, not the
> + * location, like it should (as of gcc 2.91.66)
> + *
> + * Note that the context and timing of this function is pretty critical.
> + * With a minimal amount of things going on in the caller and in here, gcc
> + * does a good job of being just a dumb compiler. Watch the assembly output
> + * if anything changes, though, and make sure everything is going in the right
> + * place.
> + */
> +static inline void suspend2_save_processor_context(void)
> +{
> + /*
> + * save the general registers.
> + * note that gcc has constructs to specify output of certain registers,
> + * but they're not used here, because it assumes that you want to modify
> + * those registers, so it tries to be smart and save them beforehand.
> + * It's really not necessary, and kinda fishy (check the assembly output),
> + * so it's avoided.
> + */
> + asm volatile ("movl %%rsp, (%0)" : "=m" (suspend2_saved_context.esp));
> + asm volatile ("movl %%rax, (%0)" : "=m" (suspend2_saved_context.eax));
> + asm volatile ("movl %%rbx, (%0)" : "=m" (suspend2_saved_context.ebx));
> + asm volatile ("movl %%rcx, (%0)" : "=m" (suspend2_saved_context.ecx));
> + asm volatile ("movl %%rdx, (%0)" : "=m" (suspend2_saved_context.edx));
> + asm volatile ("movl %%rbp, (%0)" : "=m" (suspend2_saved_context.ebp));
> + asm volatile ("movl %%rsi, (%0)" : "=m" (suspend2_saved_context.esi));
> + asm volatile ("movl %%rdi, (%0)" : "=m" (suspend2_saved_context.edi));
> + asm volatile ("movl %%r8, (%0)" : "=m" (suspend2_saved_context.r8));
> + asm volatile ("movl %%r9, (%0)" : "=m" (suspend2_saved_context.r9));
> + asm volatile ("movl %%r10, (%0)" : "=m" (suspend2_saved_context.r10));
> + asm volatile ("movl %%r11, (%0)" : "=m" (suspend2_saved_context.r11));
> + asm volatile ("movl %%r12, (%0)" : "=m" (suspend2_saved_context.r12));
> + asm volatile ("movl %%r13, (%0)" : "=m" (suspend2_saved_context.r13));
> + asm volatile ("movl %%r14, (%0)" : "=m" (suspend2_saved_context.r14));
> + asm volatile ("movl %%r15, (%0)" : "=m" (suspend2_saved_context.r15));
> +
> + /*
> + * eflags
> + */
> + asm volatile ("pushfl ; popl (%0)" : "=m" (suspend2_saved_context.eflags));
> +
> + kernel_fpu_begin();
> +
> + /*
> + * descriptor tables
> + */
> + asm volatile ("sgdt (%0)" : "=m" (suspend2_saved_context.gdt_limit));
> + asm volatile ("sidt (%0)" : "=m" (suspend2_saved_context.idt_limit));
> + asm volatile ("sldt (%0)" : "=m" (suspend2_saved_context.ldt));
> + asm volatile ("str (%0)" : "=m" (suspend2_saved_context.tr));
> +
> + /*
> + * segment registers
> + */
> + asm volatile ("movw %%ds, %0" : "=r" (suspend2_saved_context.ds));
> + asm volatile ("movw %%es, %0" : "=r" (suspend2_saved_context.es));
> + asm volatile ("movw %%fs, %0" : "=r" (suspend2_saved_context.fs));
> + asm volatile ("movw %%gs, %0" : "=r" (suspend2_saved_context.gs));
> + asm volatile ("movw %%ss, %0" : "=r" (suspend2_saved_context.ss));
> +
> + rdmsrl(MSR_FS_BASE, suspend2_saved_context.fs_base);
> + rdmsrl(MSR_GS_BASE, suspend2_saved_context.gs_base);
> + rdmsrl(MSR_KERNEL_GS_BASE, suspend2_saved_context.gs_kernel_base);
> +
> + /*
> + * control registers
> + */
> + asm volatile ("movl %%cr0, %0" : "=r" (suspend2_saved_context.cr0));
> + asm volatile ("movl %%cr2, %0" : "=r" (suspend2_saved_context.cr2));
> + asm volatile ("movl %%cr3, %0" : "=r" (suspend2_saved_context.cr3));
> + asm volatile ("movl %%cr4, %0" : "=r" (suspend2_saved_context.cr4));
> +
> +}
> +
> +static void fix_processor_context(void)
> +{
> + int nr = _smp_processor_id();
> + struct tss_struct * t = &per_cpu(init_tss,nr);
> +
> + set_tss_desc(nr,t); /* This just modifies memory; should not be neccessary. But... This is neccessary, because 386 hardware has concept of busy tsc or some similar stupidity. */
> + cpu_gdt_table[nr][GDT_ENTRY_TSS].type = 9;
> +
> + syscall_init(); /* This sets MSR_*STAR and related */
> + load_TR_desc();
> + load_LDT(&current->active_mm->context); /* This does lldt */
> +
> + /*
> + * Now maybe reload the debug registers
> + */
> + if (current->thread.debugreg7){
> + loaddebug(&current->thread, 0);
> + loaddebug(&current->thread, 1);
> + loaddebug(&current->thread, 2);
> + loaddebug(&current->thread, 3);
> + /* no 4 and 5 */
> + loaddebug(&current->thread, 6);
> + loaddebug(&current->thread, 7);
> + }
> +}
> +
> +static void do_fpu_end(void)
> +{
> + /* restore FPU regs if necessary */
> + /* Do it out of line so that gcc does not move cr0 load to some stupid place */
> + kernel_fpu_end();
> + mxcsr_feature_mask_init();
> +}
> +
> +/*
> + * restore_processor_context
> + *
> + * Restore the processor context as it was before we went to sleep
> + * - descriptor tables
> + * - control registers
> + * - segment registers
> + * - flags
> + *
> + * Note that it is critical that this function is declared inline.
> + * It was separated out from restore_state to make that function
> + * a little clearer, but it needs to be inlined because we won't have a
> + * stack when we get here (so we can't push a return address).
> + */
> +static inline void restore_processor_context(void)
> +{
> + /*
> + * first restore %ds, so we can access our data properly
> + */
> + //asm volatile ("movw %0, %%ds" :: "r" ((u16)__KERNEL_DS));
> +
> + __flush_tlb_global(); /* INLINE? */
> +
> + asm volatile ("movl $24, %eax");
> + asm volatile ("movl %eax, %ds");
> +
> + /*
> + * the other general registers
> + *
> + * note that even though gcc has constructs to specify memory
> + * input into certain registers, it will try to be too smart
> + * and save them at the beginning of the function. This is esp.
> + * bad since we don't have a stack set up when we enter, and we
> + * want to preserve the values on exit. So, we set them manually.
> + */
> + asm volatile ("movl %0, %%rsp" :: "m" (suspend2_saved_context.esp));
> + asm volatile ("movl %0, %%rbp" :: "m" (suspend2_saved_context.ebp));
> + //asm volatile ("movl %0, %%eax" :: "m" (suspend2_saved_context.eax));
> + asm volatile ("movl %0, %%rbx" :: "m" (suspend2_saved_context.ebx));
> + asm volatile ("movl %0, %%rcx" :: "m" (suspend2_saved_context.ecx));
> + asm volatile ("movl %0, %%rdx" :: "m" (suspend2_saved_context.edx));
> + asm volatile ("movl %0, %%rsi" :: "m" (suspend2_saved_context.esi));
> + asm volatile ("movl %0, %%rdi" :: "m" (suspend2_saved_context.edi));
> + asm volatile ("movl %0, %%r8" :: "m" (suspend2_saved_context.r8));
> + asm volatile ("movl %0, %%r9" :: "m" (suspend2_saved_context.r9));
> + asm volatile ("movl %0, %%r10" :: "m" (suspend2_saved_context.r10));
> + asm volatile ("movl %0, %%r11" :: "m" (suspend2_saved_context.r11));
> + asm volatile ("movl %0, %%r12" :: "m" (suspend2_saved_context.r12));
> + asm volatile ("movl %0, %%r13" :: "m" (suspend2_saved_context.r13));
> + asm volatile ("movl %0, %%r14" :: "m" (suspend2_saved_context.r14));
> + asm volatile ("movl %0, %%r15" :: "m" (suspend2_saved_context.r15));
> +
> + /*
> + * the flags
> + */
> + asm volatile ("pushl %0 ; popfl" :: "m" (suspend2_saved_context.eflags));
> +
> + asm volatile ("xorq %rax, %rax");
> +
> + /*
> + * control registers
> + */
> + asm volatile ("movl %0, %%cr4" :: "r" (suspend2_saved_context.cr4));
> + asm volatile ("movl %0, %%cr3" :: "r" (suspend2_saved_context.cr3));
> + asm volatile ("movl %0, %%cr2" :: "r" (suspend2_saved_context.cr2));
> + asm volatile ("movl %0, %%cr0" :: "r" (suspend2_saved_context.cr0));
> +
> + /*
> + * segment registers
> + */
> + asm volatile ("movw %0, %%ds" :: "r" (suspend2_saved_context.ds));
> + asm volatile ("movw %0, %%es" :: "r" (suspend2_saved_context.es));
> + asm volatile ("movw %0, %%fs" :: "r" (suspend2_saved_context.fs));
> + load_gs_index(suspend2_saved_context.gs);
> + asm volatile ("movw %0, %%ss" :: "r" (suspend2_saved_context.ss));
> +
> + wrmsrl(MSR_FS_BASE, suspend2_saved_context.fs_base);
> + wrmsrl(MSR_GS_BASE, suspend2_saved_context.gs_base);
> + wrmsrl(MSR_KERNEL_GS_BASE, suspend2_saved_context.gs_kernel_base);
> +
> + /*
> + * now restore the descriptor tables to their proper values
> + * ltr is done in fix_processor_context().
> + */
> +
> + asm volatile ("lgdt (%0)" :: "m" (suspend2_saved_context.gdt_limit));
> + asm volatile ("lidt (%0)" :: "m" (suspend2_saved_context.idt_limit));
> + asm volatile ("lldt (%0)" :: "m" (suspend2_saved_context.ldt));
> +
> + fix_processor_context();
> +
> + do_fpu_end();
> +}
> +
> +#if defined(CONFIG_SUSPEND2) || defined(CONFIG_SMP)
> +extern atomic_t suspend_cpu_counter __nosavedata;
> +extern unsigned char * my_saved_context __nosavedata;
> +static unsigned long c_loops_per_jiffy_ref[NR_CPUS] __nosavedata;
> +#endif
> +
> +#ifdef CONFIG_SUSPEND2
> +#ifndef CONFIG_SMP
> +extern unsigned long loops_per_jiffy;
> +volatile static unsigned long cpu_khz_ref __nosavedata = 0;
> +#endif
> +
> +/*
> + * APIC support: These routines save the APIC
> + * configuration for the CPU on which they are
> + * being executed
> + */
> +extern void suspend_apic_save_state(void);
> +extern void suspend_apic_reload_state(void);
> +
> +#ifdef CONFIG_SMP
> +/* ------------------------------------------------
> + * BEGIN Irq affinity code, based on code from LKCD.
> + *
> + * IRQ affinity support:
> + * Save and restore IRQ affinities, and set them
> + * all to CPU 0.
> + *
> + * Section between dashes taken from LKCD code.
> + * Perhaps we should be working toward a shared library
> + * of such routines for kexec, lkcd, software suspend
> + * and whatever other similar projects there are?
> + */
> +
> +extern irq_desc_t irq_desc[];
> +extern cpumask_t irq_affinity[];
> +extern cpumask_t saved_affinity[NR_IRQS];
> +
> +/*
> + * Routine to save the old irq affinities and change affinities of all irqs to
> + * the dumping cpu.
> + */
> +static void save_and_set_irq_affinity(void)
> +{
> + int i;
> + int cpu = _smp_processor_id();
> +
> + memcpy(saved_affinity, irq_affinity, NR_IRQS * sizeof(cpumask_t));
> + for (i = 0; i < NR_IRQS; i++) {
> + if (irq_desc[i].handler == NULL)
> + continue;
> + irq_affinity[i] = cpumask_of_cpu(cpu);
> + if (irq_desc[i].handler->set_affinity != NULL)
> + irq_desc[i].handler->set_affinity(i, irq_affinity[i]);
> + }
> +}
> +
> +/*
> + * Restore old irq affinities.
> + */
> +static void reset_irq_affinity(void)
> +{
> + int i;
> +
> + memcpy(irq_affinity, saved_affinity, NR_IRQS * sizeof(cpumask_t));
> + for (i = 0; i < NR_IRQS; i++) {
> + if (irq_desc[i].handler == NULL)
> + continue;
> + if (irq_desc[i].handler->set_affinity != NULL)
> + irq_desc[i].handler->set_affinity(i, irq_affinity[i]);
> + }
> +}
> +
> +/*
> + * END of IRQ affinity code, based on LKCD code.
> + * -----------------------------------------------------------------
> + */
> +#else
> +#define save_and_set_irq_affinity() do { } while(0)
> +#define reset_irq_affinity() do { } while(0)
> +#endif
> +
> +static inline void suspend2_pre_copy(void)
> +{
> + /*
> + * Save the irq affinities before we freeze the
> + * other processors!
> + */
> + save_and_set_irq_affinity();
> + mtrr_save();
> +}
> +
> +static inline void suspend2_post_copy(void)
> +{
> +}
> +
> +static inline void suspend2_pre_copyback(void)
> +{
> +
> + /* Send all IRQs to CPU 0. We will replace the saved affinities
> + * with the suspend-time ones when we copy the original kernel
> + * back in place
> + */
> + save_and_set_irq_affinity();
> +
> + c_loops_per_jiffy_ref[_smp_processor_id()] = current_cpu_data.loops_per_jiffy;
> +#ifndef CONFIG_SMP
> + cpu_khz_ref = cpu_khz;
> + c_loops_per_jiffy_ref[_smp_processor_id()] = loops_per_jiffy;
> +#endif
> +
> + /* We want to run from swsusp_pg_dir, since swsusp_pg_dir is stored in constant
> + * place in memory
> + */
> +
> + __asm__( "movl %%ecx,%%cr3\n" ::"c"(__pa(swsusp_pg_dir)));
> + __asm__( "leaq init_level4_pgt(%rip),%rax");
> + __asm__( "subq $__START_KERNEL_map,%rax");
> + __asm__( "movq %rax,%cr3");
> +}
> +
> +static inline void suspend2_restore_processor_context(void)
> +{
> + restore_processor_context();
> +}
> +
> +static inline void suspend2_flush_caches(void)
> +{
> + cpu_clear(_smp_processor_id(), per_cpu(cpu_tlbstate, _smp_processor_id()).active_mm->cpu_vm_mask);
> + wbinvd();
> + __flush_tlb_all();
> +
> +}
> +
> +static inline void suspend2_post_copyback(void)
> +{
> + mtrr_restore_one_cpu();
> +
> + /* Get other CPUs to restore their contexts and flush their tlbs. */
> + clear_suspend_state(SUSPEND_FREEZE_SMP);
> +
> + do {
> + cpu_relax();
> + barrier();
> + } while (atomic_read(&suspend_cpu_counter));
> + mtrr_restore_finish();
> +
> + BUG_ON(!irqs_disabled());
> +
> + /* put the irq affinity tables back */
> + reset_irq_affinity();
> +
> + current_cpu_data.loops_per_jiffy = c_loops_per_jiffy_ref[_smp_processor_id()];
> +#ifndef CONFIG_SMP
> + loops_per_jiffy = c_loops_per_jiffy_ref[_smp_processor_id()];
> + cpu_khz = cpu_khz_ref;
> +#endif
> +}
> +
> +#endif
> diff -ruNp 520-version-specific-x86_64.patch-old/include/asm-x86_64/suspend.h 520-version-specific-x86_64.patch-new/include/asm-x86_64/suspend.h
> --- 520-version-specific-x86_64.patch-old/include/asm-x86_64/suspend.h 2005-06-20 11:47:28.000000000 +1000
> +++ 520-version-specific-x86_64.patch-new/include/asm-x86_64/suspend.h 2005-07-04 23:14:19.000000000 +1000
> @@ -43,7 +43,7 @@ extern unsigned long saved_context_eflag
> : /* no output */ \
> :"r" ((thread)->debugreg##register))
>
> -extern void fix_processor_context(void);
> +/* extern void fix_processor_context(void); */
>
> #ifdef CONFIG_ACPI_SLEEP
> extern unsigned long saved_eip;
>
> -
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--
Evolution.
Enumerate the requirements.
Consider the interdependencies.
Calculate the probabilities.
Be amazed that people believe it happened.

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