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1 #ifndef _ASM_X86_PROCESSOR_H
2 #define _ASM_X86_PROCESSOR_H
3
4 #include <asm/processor-flags.h>
5
6 /* Forward declaration, a strange C thing */
7 struct task_struct;
8 struct mm_struct;
9
10 #include <asm/vm86.h>
11 #include <asm/math_emu.h>
12 #include <asm/segment.h>
13 #include <asm/types.h>
14 #include <asm/sigcontext.h>
15 #include <asm/current.h>
16 #include <asm/cpufeature.h>
17 #include <asm/system.h>
18 #include <asm/page.h>
19 #include <asm/percpu.h>
20 #include <asm/msr.h>
21 #include <asm/desc_defs.h>
22 #include <asm/nops.h>
23 #include <asm/ds.h>
24
25 #include <linux/personality.h>
26 #include <linux/cpumask.h>
27 #include <linux/cache.h>
28 #include <linux/threads.h>
29 #include <linux/init.h>
30
31 /*
32 * Default implementation of macro that returns current
33 * instruction pointer ("program counter").
34 */
35 static inline void *current_text_addr(void)
36 {
37 void *pc;
38
39 asm volatile("mov $1f, %0; 1:":"=r" (pc));
40
41 return pc;
42 }
43
44 #ifdef CONFIG_X86_VSMP
45 # define ARCH_MIN_TASKALIGN (1 << INTERNODE_CACHE_SHIFT)
46 # define ARCH_MIN_MMSTRUCT_ALIGN (1 << INTERNODE_CACHE_SHIFT)
47 #else
48 # define ARCH_MIN_TASKALIGN 16
49 # define ARCH_MIN_MMSTRUCT_ALIGN 0
50 #endif
51
52 /*
53 * CPU type and hardware bug flags. Kept separately for each CPU.
54 * Members of this structure are referenced in head.S, so think twice
55 * before touching them. [mj]
56 */
57
58 struct cpuinfo_x86 {
59 __u8 x86; /* CPU family */
60 __u8 x86_vendor; /* CPU vendor */
61 __u8 x86_model;
62 __u8 x86_mask;
63 #ifdef CONFIG_X86_32
64 char wp_works_ok; /* It doesn't on 386's */
65
66 /* Problems on some 486Dx4's and old 386's: */
67 char hlt_works_ok;
68 char hard_math;
69 char rfu;
70 char fdiv_bug;
71 char f00f_bug;
72 char coma_bug;
73 char pad0;
74 #else
75 /* Number of 4K pages in DTLB/ITLB combined(in pages): */
76 int x86_tlbsize;
77 __u8 x86_virt_bits;
78 __u8 x86_phys_bits;
79 #endif
80 /* CPUID returned core id bits: */
81 __u8 x86_coreid_bits;
82 /* Max extended CPUID function supported: */
83 __u32 extended_cpuid_level;
84 /* Maximum supported CPUID level, -1=no CPUID: */
85 int cpuid_level;
86 __u32 x86_capability[NCAPINTS];
87 char x86_vendor_id[16];
88 char x86_model_id[64];
89 /* in KB - valid for CPUS which support this call: */
90 int x86_cache_size;
91 int x86_cache_alignment; /* In bytes */
92 int x86_power;
93 unsigned long loops_per_jiffy;
94 #ifdef CONFIG_SMP
95 /* cpus sharing the last level cache: */
96 cpumask_t llc_shared_map;
97 #endif
98 /* cpuid returned max cores value: */
99 u16 x86_max_cores;
100 u16 apicid;
101 u16 initial_apicid;
102 u16 x86_clflush_size;
103 #ifdef CONFIG_SMP
104 /* number of cores as seen by the OS: */
105 u16 booted_cores;
106 /* Physical processor id: */
107 u16 phys_proc_id;
108 /* Core id: */
109 u16 cpu_core_id;
110 /* Index into per_cpu list: */
111 u16 cpu_index;
112 #endif
113 unsigned int x86_hyper_vendor;
114 } __attribute__((__aligned__(SMP_CACHE_BYTES)));
115
116 #define X86_VENDOR_INTEL 0
117 #define X86_VENDOR_CYRIX 1
118 #define X86_VENDOR_AMD 2
119 #define X86_VENDOR_UMC 3
120 #define X86_VENDOR_CENTAUR 5
121 #define X86_VENDOR_TRANSMETA 7
122 #define X86_VENDOR_NSC 8
123 #define X86_VENDOR_NUM 9
124
125 #define X86_VENDOR_UNKNOWN 0xff
126
127 #define X86_HYPER_VENDOR_NONE 0
128 #define X86_HYPER_VENDOR_VMWARE 1
129
130 /*
131 * capabilities of CPUs
132 */
133 extern struct cpuinfo_x86 boot_cpu_data;
134 extern struct cpuinfo_x86 new_cpu_data;
135
136 extern struct tss_struct doublefault_tss;
137 extern __u32 cleared_cpu_caps[NCAPINTS];
138
139 #ifdef CONFIG_SMP
140 DECLARE_PER_CPU(struct cpuinfo_x86, cpu_info);
141 #define cpu_data(cpu) per_cpu(cpu_info, cpu)
142 #define current_cpu_data __get_cpu_var(cpu_info)
143 #else
144 #define cpu_data(cpu) boot_cpu_data
145 #define current_cpu_data boot_cpu_data
146 #endif
147
148 extern const struct seq_operations cpuinfo_op;
149
150 static inline int hlt_works(int cpu)
151 {
152 #ifdef CONFIG_X86_32
153 return cpu_data(cpu).hlt_works_ok;
154 #else
155 return 1;
156 #endif
157 }
158
159 #define cache_line_size() (boot_cpu_data.x86_cache_alignment)
160
161 extern void cpu_detect(struct cpuinfo_x86 *c);
162
163 extern struct pt_regs *idle_regs(struct pt_regs *);
164
165 extern void early_cpu_init(void);
166 extern void identify_boot_cpu(void);
167 extern void identify_secondary_cpu(struct cpuinfo_x86 *);
168 extern void print_cpu_info(struct cpuinfo_x86 *);
169 extern void init_scattered_cpuid_features(struct cpuinfo_x86 *c);
170 extern unsigned int init_intel_cacheinfo(struct cpuinfo_x86 *c);
171 extern unsigned short num_cache_leaves;
172
173 extern void detect_extended_topology(struct cpuinfo_x86 *c);
174 extern void detect_ht(struct cpuinfo_x86 *c);
175
176 static inline void native_cpuid(unsigned int *eax, unsigned int *ebx,
177 unsigned int *ecx, unsigned int *edx)
178 {
179 /* ecx is often an input as well as an output. */
180 asm("cpuid"
181 : "=a" (*eax),
182 "=b" (*ebx),
183 "=c" (*ecx),
184 "=d" (*edx)
185 : "0" (*eax), "2" (*ecx));
186 }
187
188 static inline void load_cr3(pgd_t *pgdir)
189 {
190 write_cr3(__pa(pgdir));
191 }
192
193 #ifdef CONFIG_X86_32
194 /* This is the TSS defined by the hardware. */
195 struct x86_hw_tss {
196 unsigned short back_link, __blh;
197 unsigned long sp0;
198 unsigned short ss0, __ss0h;
199 unsigned long sp1;
200 /* ss1 caches MSR_IA32_SYSENTER_CS: */
201 unsigned short ss1, __ss1h;
202 unsigned long sp2;
203 unsigned short ss2, __ss2h;
204 unsigned long __cr3;
205 unsigned long ip;
206 unsigned long flags;
207 unsigned long ax;
208 unsigned long cx;
209 unsigned long dx;
210 unsigned long bx;
211 unsigned long sp;
212 unsigned long bp;
213 unsigned long si;
214 unsigned long di;
215 unsigned short es, __esh;
216 unsigned short cs, __csh;
217 unsigned short ss, __ssh;
218 unsigned short ds, __dsh;
219 unsigned short fs, __fsh;
220 unsigned short gs, __gsh;
221 unsigned short ldt, __ldth;
222 unsigned short trace;
223 unsigned short io_bitmap_base;
224
225 } __attribute__((packed));
226 #else
227 struct x86_hw_tss {
228 u32 reserved1;
229 u64 sp0;
230 u64 sp1;
231 u64 sp2;
232 u64 reserved2;
233 u64 ist[7];
234 u32 reserved3;
235 u32 reserved4;
236 u16 reserved5;
237 u16 io_bitmap_base;
238
239 } __attribute__((packed)) ____cacheline_aligned;
240 #endif
241
242 /*
243 * IO-bitmap sizes:
244 */
245 #define IO_BITMAP_BITS 65536
246 #define IO_BITMAP_BYTES (IO_BITMAP_BITS/8)
247 #define IO_BITMAP_LONGS (IO_BITMAP_BYTES/sizeof(long))
248 #define IO_BITMAP_OFFSET offsetof(struct tss_struct, io_bitmap)
249 #define INVALID_IO_BITMAP_OFFSET 0x8000
250 #define INVALID_IO_BITMAP_OFFSET_LAZY 0x9000
251
252 struct tss_struct {
253 /*
254 * The hardware state:
255 */
256 struct x86_hw_tss x86_tss;
257
258 /*
259 * The extra 1 is there because the CPU will access an
260 * additional byte beyond the end of the IO permission
261 * bitmap. The extra byte must be all 1 bits, and must
262 * be within the limit.
263 */
264 unsigned long io_bitmap[IO_BITMAP_LONGS + 1];
265 /*
266 * Cache the current maximum and the last task that used the bitmap:
267 */
268 unsigned long io_bitmap_max;
269 struct thread_struct *io_bitmap_owner;
270
271 /*
272 * .. and then another 0x100 bytes for the emergency kernel stack:
273 */
274 unsigned long stack[64];
275
276 } ____cacheline_aligned;
277
278 DECLARE_PER_CPU(struct tss_struct, init_tss);
279
280 /*
281 * Save the original ist values for checking stack pointers during debugging
282 */
283 struct orig_ist {
284 unsigned long ist[7];
285 };
286
287 #define MXCSR_DEFAULT 0x1f80
288
289 struct i387_fsave_struct {
290 u32 cwd; /* FPU Control Word */
291 u32 swd; /* FPU Status Word */
292 u32 twd; /* FPU Tag Word */
293 u32 fip; /* FPU IP Offset */
294 u32 fcs; /* FPU IP Selector */
295 u32 foo; /* FPU Operand Pointer Offset */
296 u32 fos; /* FPU Operand Pointer Selector */
297
298 /* 8*10 bytes for each FP-reg = 80 bytes: */
299 u32 st_space[20];
300
301 /* Software status information [not touched by FSAVE ]: */
302 u32 status;
303 };
304
305 struct i387_fxsave_struct {
306 u16 cwd; /* Control Word */
307 u16 swd; /* Status Word */
308 u16 twd; /* Tag Word */
309 u16 fop; /* Last Instruction Opcode */
310 union {
311 struct {
312 u64 rip; /* Instruction Pointer */
313 u64 rdp; /* Data Pointer */
314 };
315 struct {
316 u32 fip; /* FPU IP Offset */
317 u32 fcs; /* FPU IP Selector */
318 u32 foo; /* FPU Operand Offset */
319 u32 fos; /* FPU Operand Selector */
320 };
321 };
322 u32 mxcsr; /* MXCSR Register State */
323 u32 mxcsr_mask; /* MXCSR Mask */
324
325 /* 8*16 bytes for each FP-reg = 128 bytes: */
326 u32 st_space[32];
327
328 /* 16*16 bytes for each XMM-reg = 256 bytes: */
329 u32 xmm_space[64];
330
331 u32 padding[12];
332
333 union {
334 u32 padding1[12];
335 u32 sw_reserved[12];
336 };
337
338 } __attribute__((aligned(16)));
339
340 struct i387_soft_struct {
341 u32 cwd;
342 u32 swd;
343 u32 twd;
344 u32 fip;
345 u32 fcs;
346 u32 foo;
347 u32 fos;
348 /* 8*10 bytes for each FP-reg = 80 bytes: */
349 u32 st_space[20];
350 u8 ftop;
351 u8 changed;
352 u8 lookahead;
353 u8 no_update;
354 u8 rm;
355 u8 alimit;
356 struct math_emu_info *info;
357 u32 entry_eip;
358 };
359
360 struct xsave_hdr_struct {
361 u64 xstate_bv;
362 u64 reserved1[2];
363 u64 reserved2[5];
364 } __attribute__((packed));
365
366 struct xsave_struct {
367 struct i387_fxsave_struct i387;
368 struct xsave_hdr_struct xsave_hdr;
369 /* new processor state extensions will go here */
370 } __attribute__ ((packed, aligned (64)));
371
372 union thread_xstate {
373 struct i387_fsave_struct fsave;
374 struct i387_fxsave_struct fxsave;
375 struct i387_soft_struct soft;
376 struct xsave_struct xsave;
377 };
378
379 #ifdef CONFIG_X86_64
380 DECLARE_PER_CPU(struct orig_ist, orig_ist);
381
382 union irq_stack_union {
383 char irq_stack[IRQ_STACK_SIZE];
384 /*
385 * GCC hardcodes the stack canary as %gs:40. Since the
386 * irq_stack is the object at %gs:0, we reserve the bottom
387 * 48 bytes of the irq stack for the canary.
388 */
389 struct {
390 char gs_base[40];
391 unsigned long stack_canary;
392 };
393 };
394
395 DECLARE_PER_CPU(union irq_stack_union, irq_stack_union);
396 DECLARE_INIT_PER_CPU(irq_stack_union);
397
398 DECLARE_PER_CPU(char *, irq_stack_ptr);
399 #else /* X86_64 */
400 #ifdef CONFIG_CC_STACKPROTECTOR
401 DECLARE_PER_CPU(unsigned long, stack_canary);
402 #endif
403 #endif /* X86_64 */
404
405 extern void print_cpu_info(struct cpuinfo_x86 *);
406 extern unsigned int xstate_size;
407 extern void free_thread_xstate(struct task_struct *);
408 extern struct kmem_cache *task_xstate_cachep;
409 extern void init_scattered_cpuid_features(struct cpuinfo_x86 *c);
410 extern unsigned int init_intel_cacheinfo(struct cpuinfo_x86 *c);
411 extern unsigned short num_cache_leaves;
412
413 struct thread_struct {
414 /* Cached TLS descriptors: */
415 struct desc_struct tls_array[GDT_ENTRY_TLS_ENTRIES];
416 unsigned long sp0;
417 unsigned long sp;
418 #ifdef CONFIG_X86_32
419 unsigned long sysenter_cs;
420 #else
421 unsigned long usersp; /* Copy from PDA */
422 unsigned short es;
423 unsigned short ds;
424 unsigned short fsindex;
425 unsigned short gsindex;
426 #endif
427 unsigned long ip;
428 unsigned long fs;
429 unsigned long gs;
430 /* Hardware debugging registers: */
431 unsigned long debugreg0;
432 unsigned long debugreg1;
433 unsigned long debugreg2;
434 unsigned long debugreg3;
435 unsigned long debugreg6;
436 unsigned long debugreg7;
437 /* Fault info: */
438 unsigned long cr2;
439 unsigned long trap_no;
440 unsigned long error_code;
441 /* floating point and extended processor state */
442 union thread_xstate *xstate;
443 #ifdef CONFIG_X86_32
444 /* Virtual 86 mode info */
445 struct vm86_struct __user *vm86_info;
446 unsigned long screen_bitmap;
447 unsigned long v86flags;
448 unsigned long v86mask;
449 unsigned long saved_sp0;
450 unsigned int saved_fs;
451 unsigned int saved_gs;
452 #endif
453 /* IO permissions: */
454 unsigned long *io_bitmap_ptr;
455 unsigned long iopl;
456 /* Max allowed port in the bitmap, in bytes: */
457 unsigned io_bitmap_max;
458 /* MSR_IA32_DEBUGCTLMSR value to switch in if TIF_DEBUGCTLMSR is set. */
459 unsigned long debugctlmsr;
460 #ifdef CONFIG_X86_DS
461 /* Debug Store context; see include/asm-x86/ds.h; goes into MSR_IA32_DS_AREA */
462 struct ds_context *ds_ctx;
463 #endif /* CONFIG_X86_DS */
464 #ifdef CONFIG_X86_PTRACE_BTS
465 /* the signal to send on a bts buffer overflow */
466 unsigned int bts_ovfl_signal;
467 #endif /* CONFIG_X86_PTRACE_BTS */
468 };
469
470 static inline unsigned long native_get_debugreg(int regno)
471 {
472 unsigned long val = 0; /* Damn you, gcc! */
473
474 switch (regno) {
475 case 0:
476 asm("mov %%db0, %0" :"=r" (val));
477 break;
478 case 1:
479 asm("mov %%db1, %0" :"=r" (val));
480 break;
481 case 2:
482 asm("mov %%db2, %0" :"=r" (val));
483 break;
484 case 3:
485 asm("mov %%db3, %0" :"=r" (val));
486 break;
487 case 6:
488 asm("mov %%db6, %0" :"=r" (val));
489 break;
490 case 7:
491 asm("mov %%db7, %0" :"=r" (val));
492 break;
493 default:
494 BUG();
495 }
496 return val;
497 }
498
499 static inline void native_set_debugreg(int regno, unsigned long value)
500 {
501 switch (regno) {
502 case 0:
503 asm("mov %0, %%db0" ::"r" (value));
504 break;
505 case 1:
506 asm("mov %0, %%db1" ::"r" (value));
507 break;
508 case 2:
509 asm("mov %0, %%db2" ::"r" (value));
510 break;
511 case 3:
512 asm("mov %0, %%db3" ::"r" (value));
513 break;
514 case 6:
515 asm("mov %0, %%db6" ::"r" (value));
516 break;
517 case 7:
518 asm("mov %0, %%db7" ::"r" (value));
519 break;
520 default:
521 BUG();
522 }
523 }
524
525 /*
526 * Set IOPL bits in EFLAGS from given mask
527 */
528 static inline void native_set_iopl_mask(unsigned mask)
529 {
530 #ifdef CONFIG_X86_32
531 unsigned int reg;
532
533 asm volatile ("pushfl;"
534 "popl %0;"
535 "andl %1, %0;"
536 "orl %2, %0;"
537 "pushl %0;"
538 "popfl"
539 : "=&r" (reg)
540 : "i" (~X86_EFLAGS_IOPL), "r" (mask));
541 #endif
542 }
543
544 static inline void
545 native_load_sp0(struct tss_struct *tss, struct thread_struct *thread)
546 {
547 tss->x86_tss.sp0 = thread->sp0;
548 #ifdef CONFIG_X86_32
549 /* Only happens when SEP is enabled, no need to test "SEP"arately: */
550 if (unlikely(tss->x86_tss.ss1 != thread->sysenter_cs)) {
551 tss->x86_tss.ss1 = thread->sysenter_cs;
552 wrmsr(MSR_IA32_SYSENTER_CS, thread->sysenter_cs, 0);
553 }
554 #endif
555 }
556
557 static inline void native_swapgs(void)
558 {
559 #ifdef CONFIG_X86_64
560 asm volatile("swapgs" ::: "memory");
561 #endif
562 }
563
564 #ifdef CONFIG_PARAVIRT
565 #include <asm/paravirt.h>
566 #else
567 #define __cpuid native_cpuid
568 #define paravirt_enabled() 0
569
570 /*
571 * These special macros can be used to get or set a debugging register
572 */
573 #define get_debugreg(var, register) \
574 (var) = native_get_debugreg(register)
575 #define set_debugreg(value, register) \
576 native_set_debugreg(register, value)
577
578 static inline void load_sp0(struct tss_struct *tss,
579 struct thread_struct *thread)
580 {
581 native_load_sp0(tss, thread);
582 }
583
584 #define set_iopl_mask native_set_iopl_mask
585 #endif /* CONFIG_PARAVIRT */
586
587 /*
588 * Save the cr4 feature set we're using (ie
589 * Pentium 4MB enable and PPro Global page
590 * enable), so that any CPU's that boot up
591 * after us can get the correct flags.
592 */
593 extern unsigned long mmu_cr4_features;
594
595 static inline void set_in_cr4(unsigned long mask)
596 {
597 unsigned cr4;
598
599 mmu_cr4_features |= mask;
600 cr4 = read_cr4();
601 cr4 |= mask;
602 write_cr4(cr4);
603 }
604
605 static inline void clear_in_cr4(unsigned long mask)
606 {
607 unsigned cr4;
608
609 mmu_cr4_features &= ~mask;
610 cr4 = read_cr4();
611 cr4 &= ~mask;
612 write_cr4(cr4);
613 }
614
615 typedef struct {
616 unsigned long seg;
617 } mm_segment_t;
618
619
620 /*
621 * create a kernel thread without removing it from tasklists
622 */
623 extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
624
625 /* Free all resources held by a thread. */
626 extern void release_thread(struct task_struct *);
627
628 /* Prepare to copy thread state - unlazy all lazy state */
629 extern void prepare_to_copy(struct task_struct *tsk);
630
631 unsigned long get_wchan(struct task_struct *p);
632
633 /*
634 * Generic CPUID function
635 * clear %ecx since some cpus (Cyrix MII) do not set or clear %ecx
636 * resulting in stale register contents being returned.
637 */
638 static inline void cpuid(unsigned int op,
639 unsigned int *eax, unsigned int *ebx,
640 unsigned int *ecx, unsigned int *edx)
641 {
642 *eax = op;
643 *ecx = 0;
644 __cpuid(eax, ebx, ecx, edx);
645 }
646
647 /* Some CPUID calls want 'count' to be placed in ecx */
648 static inline void cpuid_count(unsigned int op, int count,
649 unsigned int *eax, unsigned int *ebx,
650 unsigned int *ecx, unsigned int *edx)
651 {
652 *eax = op;
653 *ecx = count;
654 __cpuid(eax, ebx, ecx, edx);
655 }
656
657 /*
658 * CPUID functions returning a single datum
659 */
660 static inline unsigned int cpuid_eax(unsigned int op)
661 {
662 unsigned int eax, ebx, ecx, edx;
663
664 cpuid(op, &eax, &ebx, &ecx, &edx);
665
666 return eax;
667 }
668
669 static inline unsigned int cpuid_ebx(unsigned int op)
670 {
671 unsigned int eax, ebx, ecx, edx;
672
673 cpuid(op, &eax, &ebx, &ecx, &edx);
674
675 return ebx;
676 }
677
678 static inline unsigned int cpuid_ecx(unsigned int op)
679 {
680 unsigned int eax, ebx, ecx, edx;
681
682 cpuid(op, &eax, &ebx, &ecx, &edx);
683
684 return ecx;
685 }
686
687 static inline unsigned int cpuid_edx(unsigned int op)
688 {
689 unsigned int eax, ebx, ecx, edx;
690
691 cpuid(op, &eax, &ebx, &ecx, &edx);
692
693 return edx;
694 }
695
696 /* REP NOP (PAUSE) is a good thing to insert into busy-wait loops. */
697 static inline void rep_nop(void)
698 {
699 asm volatile("rep; nop" ::: "memory");
700 }
701
702 static inline void cpu_relax(void)
703 {
704 rep_nop();
705 }
706
707 /* Stop speculative execution: */
708 static inline void sync_core(void)
709 {
710 int tmp;
711
712 asm volatile("cpuid" : "=a" (tmp) : "0" (1)
713 : "ebx", "ecx", "edx", "memory");
714 }
715
716 static inline void __monitor(const void *eax, unsigned long ecx,
717 unsigned long edx)
718 {
719 /* "monitor %eax, %ecx, %edx;" */
720 asm volatile(".byte 0x0f, 0x01, 0xc8;"
721 :: "a" (eax), "c" (ecx), "d"(edx));
722 }
723
724 static inline void __mwait(unsigned long eax, unsigned long ecx)
725 {
726 /* "mwait %eax, %ecx;" */
727 asm volatile(".byte 0x0f, 0x01, 0xc9;"
728 :: "a" (eax), "c" (ecx));
729 }
730
731 static inline void __sti_mwait(unsigned long eax, unsigned long ecx)
732 {
733 trace_hardirqs_on();
734 /* "mwait %eax, %ecx;" */
735 asm volatile("sti; .byte 0x0f, 0x01, 0xc9;"
736 :: "a" (eax), "c" (ecx));
737 }
738
739 extern void mwait_idle_with_hints(unsigned long eax, unsigned long ecx);
740
741 extern void select_idle_routine(const struct cpuinfo_x86 *c);
742
743 extern unsigned long boot_option_idle_override;
744 extern unsigned long idle_halt;
745 extern unsigned long idle_nomwait;
746
747 /*
748 * on systems with caches, caches must be flashed as the absolute
749 * last instruction before going into a suspended halt. Otherwise,
750 * dirty data can linger in the cache and become stale on resume,
751 * leading to strange errors.
752 *
753 * perform a variety of operations to guarantee that the compiler
754 * will not reorder instructions. wbinvd itself is serializing
755 * so the processor will not reorder.
756 *
757 * Systems without cache can just go into halt.
758 */
759 static inline void wbinvd_halt(void)
760 {
761 mb();
762 /* check for clflush to determine if wbinvd is legal */
763 if (cpu_has_clflush)
764 asm volatile("cli; wbinvd; 1: hlt; jmp 1b" : : : "memory");
765 else
766 while (1)
767 halt();
768 }
769
770 extern void enable_sep_cpu(void);
771 extern int sysenter_setup(void);
772
773 /* Defined in head.S */
774 extern struct desc_ptr early_gdt_descr;
775
776 extern void cpu_set_gdt(int);
777 extern void switch_to_new_gdt(int);
778 extern void load_percpu_segment(int);
779 extern void cpu_init(void);
780
781 static inline unsigned long get_debugctlmsr(void)
782 {
783 unsigned long debugctlmsr = 0;
784
785 #ifndef CONFIG_X86_DEBUGCTLMSR
786 if (boot_cpu_data.x86 < 6)
787 return 0;
788 #endif
789 rdmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
790
791 return debugctlmsr;
792 }
793
794 static inline void update_debugctlmsr(unsigned long debugctlmsr)
795 {
796 #ifndef CONFIG_X86_DEBUGCTLMSR
797 if (boot_cpu_data.x86 < 6)
798 return;
799 #endif
800 wrmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
801 }
802
803 /*
804 * from system description table in BIOS. Mostly for MCA use, but
805 * others may find it useful:
806 */
807 extern unsigned int machine_id;
808 extern unsigned int machine_submodel_id;
809 extern unsigned int BIOS_revision;
810
811 /* Boot loader type from the setup header: */
812 extern int bootloader_type;
813
814 extern char ignore_fpu_irq;
815
816 #define HAVE_ARCH_PICK_MMAP_LAYOUT 1
817 #define ARCH_HAS_PREFETCHW
818 #define ARCH_HAS_SPINLOCK_PREFETCH
819
820 #ifdef CONFIG_X86_32
821 # define BASE_PREFETCH ASM_NOP4
822 # define ARCH_HAS_PREFETCH
823 #else
824 # define BASE_PREFETCH "prefetcht0 (%1)"
825 #endif
826
827 /*
828 * Prefetch instructions for Pentium III (+) and AMD Athlon (+)
829 *
830 * It's not worth to care about 3dnow prefetches for the K6
831 * because they are microcoded there and very slow.
832 */
833 static inline void prefetch(const void *x)
834 {
835 alternative_input(BASE_PREFETCH,
836 "prefetchnta (%1)",
837 X86_FEATURE_XMM,
838 "r" (x));
839 }
840
841 /*
842 * 3dnow prefetch to get an exclusive cache line.
843 * Useful for spinlocks to avoid one state transition in the
844 * cache coherency protocol:
845 */
846 static inline void prefetchw(const void *x)
847 {
848 alternative_input(BASE_PREFETCH,
849 "prefetchw (%1)",
850 X86_FEATURE_3DNOW,
851 "r" (x));
852 }
853
854 static inline void spin_lock_prefetch(const void *x)
855 {
856 prefetchw(x);
857 }
858
859 #ifdef CONFIG_X86_32
860 /*
861 * User space process size: 3GB (default).
862 */
863 #define TASK_SIZE PAGE_OFFSET
864 #define STACK_TOP TASK_SIZE
865 #define STACK_TOP_MAX STACK_TOP
866
867 #define INIT_THREAD { \
868 .sp0 = sizeof(init_stack) + (long)&init_stack, \
869 .vm86_info = NULL, \
870 .sysenter_cs = __KERNEL_CS, \
871 .io_bitmap_ptr = NULL, \
872 .fs = __KERNEL_PERCPU, \
873 }
874
875 /*
876 * Note that the .io_bitmap member must be extra-big. This is because
877 * the CPU will access an additional byte beyond the end of the IO
878 * permission bitmap. The extra byte must be all 1 bits, and must
879 * be within the limit.
880 */
881 #define INIT_TSS { \
882 .x86_tss = { \
883 .sp0 = sizeof(init_stack) + (long)&init_stack, \
884 .ss0 = __KERNEL_DS, \
885 .ss1 = __KERNEL_CS, \
886 .io_bitmap_base = INVALID_IO_BITMAP_OFFSET, \
887 }, \
888 .io_bitmap = { [0 ... IO_BITMAP_LONGS] = ~0 }, \
889 }
890
891 extern unsigned long thread_saved_pc(struct task_struct *tsk);
892
893 #define THREAD_SIZE_LONGS (THREAD_SIZE/sizeof(unsigned long))
894 #define KSTK_TOP(info) \
895 ({ \
896 unsigned long *__ptr = (unsigned long *)(info); \
897 (unsigned long)(&__ptr[THREAD_SIZE_LONGS]); \
898 })
899
900 /*
901 * The below -8 is to reserve 8 bytes on top of the ring0 stack.
902 * This is necessary to guarantee that the entire "struct pt_regs"
903 * is accessable even if the CPU haven't stored the SS/ESP registers
904 * on the stack (interrupt gate does not save these registers
905 * when switching to the same priv ring).
906 * Therefore beware: accessing the ss/esp fields of the
907 * "struct pt_regs" is possible, but they may contain the
908 * completely wrong values.
909 */
910 #define task_pt_regs(task) \
911 ({ \
912 struct pt_regs *__regs__; \
913 __regs__ = (struct pt_regs *)(KSTK_TOP(task_stack_page(task))-8); \
914 __regs__ - 1; \
915 })
916
917 #define KSTK_ESP(task) (task_pt_regs(task)->sp)
918
919 #else
920 /*
921 * User space process size. 47bits minus one guard page.
922 */
923 #define TASK_SIZE64 ((1UL << 47) - PAGE_SIZE)
924
925 /* This decides where the kernel will search for a free chunk of vm
926 * space during mmap's.
927 */
928 #define IA32_PAGE_OFFSET ((current->personality & ADDR_LIMIT_3GB) ? \
929 0xc0000000 : 0xFFFFe000)
930
931 #define TASK_SIZE (test_thread_flag(TIF_IA32) ? \
932 IA32_PAGE_OFFSET : TASK_SIZE64)
933 #define TASK_SIZE_OF(child) ((test_tsk_thread_flag(child, TIF_IA32)) ? \
934 IA32_PAGE_OFFSET : TASK_SIZE64)
935
936 #define STACK_TOP TASK_SIZE
937 #define STACK_TOP_MAX TASK_SIZE64
938
939 #define INIT_THREAD { \
940 .sp0 = (unsigned long)&init_stack + sizeof(init_stack) \
941 }
942
943 #define INIT_TSS { \
944 .x86_tss.sp0 = (unsigned long)&init_stack + sizeof(init_stack) \
945 }
946
947 /*
948 * Return saved PC of a blocked thread.
949 * What is this good for? it will be always the scheduler or ret_from_fork.
950 */
951 #define thread_saved_pc(t) (*(unsigned long *)((t)->thread.sp - 8))
952
953 #define task_pt_regs(tsk) ((struct pt_regs *)(tsk)->thread.sp0 - 1)
954 #define KSTK_ESP(tsk) -1 /* sorry. doesn't work for syscall. */
955 #endif /* CONFIG_X86_64 */
956
957 extern void start_thread(struct pt_regs *regs, unsigned long new_ip,
958 unsigned long new_sp);
959
960 /*
961 * This decides where the kernel will search for a free chunk of vm
962 * space during mmap's.
963 */
964 #define TASK_UNMAPPED_BASE (PAGE_ALIGN(TASK_SIZE / 3))
965
966 #define KSTK_EIP(task) (task_pt_regs(task)->ip)
967
968 /* Get/set a process' ability to use the timestamp counter instruction */
969 #define GET_TSC_CTL(adr) get_tsc_mode((adr))
970 #define SET_TSC_CTL(val) set_tsc_mode((val))
971
972 extern int get_tsc_mode(unsigned long adr);
973 extern int set_tsc_mode(unsigned int val);
974
975 #endif /* _ASM_X86_PROCESSOR_H */