From: Glauber de Oliveira Costa Date: Wed, 30 Jan 2008 12:31:08 +0000 (+0100) Subject: x86: move switch_to macro to system.h X-Git-Tag: v2.6.25-rc1~1143^2~630 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0a3b4d151a8e57f50ce5a12c7ea5ec9965cf0b5a;p=linux-2.6 x86: move switch_to macro to system.h This patch moves the switch_to() macro to system.h As those macros are fundamentally different between i386 and x86_64, they are enclosed around an ifdef. Signed-off-by: Glauber de Oliveira Costa Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner --- diff --git a/include/asm-x86/system.h b/include/asm-x86/system.h index 4c15eb11a9..ba3403f1d0 100644 --- a/include/asm-x86/system.h +++ b/include/asm-x86/system.h @@ -6,8 +6,69 @@ #include #ifdef CONFIG_X86_32 +#define AT_VECTOR_SIZE_ARCH 2 /* entries in ARCH_DLINFO */ + +struct task_struct; /* one of the stranger aspects of C forward declarations */ +extern struct task_struct *FASTCALL(__switch_to(struct task_struct *prev, + struct task_struct *next)); + +/* + * Saving eflags is important. It switches not only IOPL between tasks, + * it also protects other tasks from NT leaking through sysenter etc. + */ +#define switch_to(prev, next, last) do { \ + unsigned long esi, edi; \ + asm volatile("pushfl\n\t" /* Save flags */ \ + "pushl %%ebp\n\t" \ + "movl %%esp,%0\n\t" /* save ESP */ \ + "movl %5,%%esp\n\t" /* restore ESP */ \ + "movl $1f,%1\n\t" /* save EIP */ \ + "pushl %6\n\t" /* restore EIP */ \ + "jmp __switch_to\n" \ + "1:\t" \ + "popl %%ebp\n\t" \ + "popfl" \ + :"=m" (prev->thread.sp), "=m" (prev->thread.ip), \ + "=a" (last), "=S" (esi), "=D" (edi) \ + :"m" (next->thread.sp), "m" (next->thread.ip), \ + "2" (prev), "d" (next)); \ +} while (0) + # include "system_32.h" #else +#define __SAVE(reg, offset) "movq %%" #reg ",(14-" #offset ")*8(%%rsp)\n\t" +#define __RESTORE(reg, offset) "movq (14-" #offset ")*8(%%rsp),%%" #reg "\n\t" + +/* frame pointer must be last for get_wchan */ +#define SAVE_CONTEXT "pushf ; pushq %%rbp ; movq %%rsi,%%rbp\n\t" +#define RESTORE_CONTEXT "movq %%rbp,%%rsi ; popq %%rbp ; popf\t" + +#define __EXTRA_CLOBBER \ + , "rcx", "rbx", "rdx", "r8", "r9", "r10", "r11", \ + "r12", "r13", "r14", "r15" + +/* Save restore flags to clear handle leaking NT */ +#define switch_to(prev, next, last) \ + asm volatile(SAVE_CONTEXT \ + "movq %%rsp,%P[threadrsp](%[prev])\n\t" /* save RSP */ \ + "movq %P[threadrsp](%[next]),%%rsp\n\t" /* restore RSP */ \ + "call __switch_to\n\t" \ + ".globl thread_return\n" \ + "thread_return:\n\t" \ + "movq %%gs:%P[pda_pcurrent],%%rsi\n\t" \ + "movq %P[thread_info](%%rsi),%%r8\n\t" \ + LOCK_PREFIX "btr %[tif_fork],%P[ti_flags](%%r8)\n\t" \ + "movq %%rax,%%rdi\n\t" \ + "jc ret_from_fork\n\t" \ + RESTORE_CONTEXT \ + : "=a" (last) \ + : [next] "S" (next), [prev] "D" (prev), \ + [threadrsp] "i" (offsetof(struct task_struct, thread.sp)), \ + [ti_flags] "i" (offsetof(struct thread_info, flags)), \ + [tif_fork] "i" (TIF_FORK), \ + [thread_info] "i" (offsetof(struct task_struct, stack)), \ + [pda_pcurrent] "i" (offsetof(struct x8664_pda, pcurrent)) \ + : "memory", "cc" __EXTRA_CLOBBER) # include "system_64.h" #endif diff --git a/include/asm-x86/system_32.h b/include/asm-x86/system_32.h index 7da0716fb3..83af46443b 100644 --- a/include/asm-x86/system_32.h +++ b/include/asm-x86/system_32.h @@ -5,37 +5,6 @@ #include #include -#ifdef __KERNEL__ -#define AT_VECTOR_SIZE_ARCH 2 /* entries in ARCH_DLINFO */ - -struct task_struct; /* one of the stranger aspects of C forward declarations.. */ -extern struct task_struct * FASTCALL(__switch_to(struct task_struct *prev, struct task_struct *next)); - -/* - * Saving eflags is important. It switches not only IOPL between tasks, - * it also protects other tasks from NT leaking through sysenter etc. - */ -#define switch_to(prev,next,last) do { \ - unsigned long esi,edi; \ - asm volatile("pushfl\n\t" /* Save flags */ \ - "pushl %%ebp\n\t" \ - "movl %%esp,%0\n\t" /* save ESP */ \ - "movl %5,%%esp\n\t" /* restore ESP */ \ - "movl $1f,%1\n\t" /* save EIP */ \ - "pushl %6\n\t" /* restore EIP */ \ - "jmp __switch_to\n" \ - "1:\t" \ - "popl %%ebp\n\t" \ - "popfl" \ - :"=m" (prev->thread.sp),"=m" (prev->thread.ip), \ - "=a" (last),"=S" (esi),"=D" (edi) \ - :"m" (next->thread.sp),"m" (next->thread.ip), \ - "2" (prev), "d" (next)); \ -} while (0) - -#endif /* __KERNEL__ */ - - #include /* diff --git a/include/asm-x86/system_64.h b/include/asm-x86/system_64.h index 9def35eb75..97fa251ccb 100644 --- a/include/asm-x86/system_64.h +++ b/include/asm-x86/system_64.h @@ -4,49 +4,6 @@ #include #include -#ifdef __KERNEL__ - -/* entries in ARCH_DLINFO: */ -#ifdef CONFIG_IA32_EMULATION -# define AT_VECTOR_SIZE_ARCH 2 -#else -# define AT_VECTOR_SIZE_ARCH 1 -#endif - -#define __SAVE(reg,offset) "movq %%" #reg ",(14-" #offset ")*8(%%rsp)\n\t" -#define __RESTORE(reg,offset) "movq (14-" #offset ")*8(%%rsp),%%" #reg "\n\t" - -/* frame pointer must be last for get_wchan */ -#define SAVE_CONTEXT "pushf ; pushq %%rbp ; movq %%rsi,%%rbp\n\t" -#define RESTORE_CONTEXT "movq %%rbp,%%rsi ; popq %%rbp ; popf\t" - -#define __EXTRA_CLOBBER \ - ,"rcx","rbx","rdx","r8","r9","r10","r11","r12","r13","r14","r15" - -/* Save restore flags to clear handle leaking NT */ -#define switch_to(prev,next,last) \ - asm volatile(SAVE_CONTEXT \ - "movq %%rsp,%P[threadrsp](%[prev])\n\t" /* save RSP */ \ - "movq %P[threadrsp](%[next]),%%rsp\n\t" /* restore RSP */ \ - "call __switch_to\n\t" \ - ".globl thread_return\n" \ - "thread_return:\n\t" \ - "movq %%gs:%P[pda_pcurrent],%%rsi\n\t" \ - "movq %P[thread_info](%%rsi),%%r8\n\t" \ - LOCK_PREFIX "btr %[tif_fork],%P[ti_flags](%%r8)\n\t" \ - "movq %%rax,%%rdi\n\t" \ - "jc ret_from_fork\n\t" \ - RESTORE_CONTEXT \ - : "=a" (last) \ - : [next] "S" (next), [prev] "D" (prev), \ - [threadrsp] "i" (offsetof(struct task_struct, thread.sp)), \ - [ti_flags] "i" (offsetof(struct thread_info, flags)),\ - [tif_fork] "i" (TIF_FORK), \ - [thread_info] "i" (offsetof(struct task_struct, stack)), \ - [pda_pcurrent] "i" (offsetof(struct x8664_pda, pcurrent)) \ - : "memory", "cc" __EXTRA_CLOBBER) - -#endif /* __KERNEL__ */ static inline unsigned long read_cr8(void) {