xref: /openbmc/linux/arch/x86/include/asm/processor.h (revision c8dbaa22)
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 struct vm86;
10 
11 #include <asm/math_emu.h>
12 #include <asm/segment.h>
13 #include <asm/types.h>
14 #include <uapi/asm/sigcontext.h>
15 #include <asm/current.h>
16 #include <asm/cpufeatures.h>
17 #include <asm/page.h>
18 #include <asm/pgtable_types.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/special_insns.h>
24 #include <asm/fpu/types.h>
25 
26 #include <linux/personality.h>
27 #include <linux/cache.h>
28 #include <linux/threads.h>
29 #include <linux/math64.h>
30 #include <linux/err.h>
31 #include <linux/irqflags.h>
32 
33 /*
34  * We handle most unaligned accesses in hardware.  On the other hand
35  * unaligned DMA can be quite expensive on some Nehalem processors.
36  *
37  * Based on this we disable the IP header alignment in network drivers.
38  */
39 #define NET_IP_ALIGN	0
40 
41 #define HBP_NUM 4
42 /*
43  * Default implementation of macro that returns current
44  * instruction pointer ("program counter").
45  */
46 static inline void *current_text_addr(void)
47 {
48 	void *pc;
49 
50 	asm volatile("mov $1f, %0; 1:":"=r" (pc));
51 
52 	return pc;
53 }
54 
55 /*
56  * These alignment constraints are for performance in the vSMP case,
57  * but in the task_struct case we must also meet hardware imposed
58  * alignment requirements of the FPU state:
59  */
60 #ifdef CONFIG_X86_VSMP
61 # define ARCH_MIN_TASKALIGN		(1 << INTERNODE_CACHE_SHIFT)
62 # define ARCH_MIN_MMSTRUCT_ALIGN	(1 << INTERNODE_CACHE_SHIFT)
63 #else
64 # define ARCH_MIN_TASKALIGN		__alignof__(union fpregs_state)
65 # define ARCH_MIN_MMSTRUCT_ALIGN	0
66 #endif
67 
68 enum tlb_infos {
69 	ENTRIES,
70 	NR_INFO
71 };
72 
73 extern u16 __read_mostly tlb_lli_4k[NR_INFO];
74 extern u16 __read_mostly tlb_lli_2m[NR_INFO];
75 extern u16 __read_mostly tlb_lli_4m[NR_INFO];
76 extern u16 __read_mostly tlb_lld_4k[NR_INFO];
77 extern u16 __read_mostly tlb_lld_2m[NR_INFO];
78 extern u16 __read_mostly tlb_lld_4m[NR_INFO];
79 extern u16 __read_mostly tlb_lld_1g[NR_INFO];
80 
81 /*
82  *  CPU type and hardware bug flags. Kept separately for each CPU.
83  *  Members of this structure are referenced in head_32.S, so think twice
84  *  before touching them. [mj]
85  */
86 
87 struct cpuinfo_x86 {
88 	__u8			x86;		/* CPU family */
89 	__u8			x86_vendor;	/* CPU vendor */
90 	__u8			x86_model;
91 	__u8			x86_mask;
92 #ifdef CONFIG_X86_64
93 	/* Number of 4K pages in DTLB/ITLB combined(in pages): */
94 	int			x86_tlbsize;
95 #endif
96 	__u8			x86_virt_bits;
97 	__u8			x86_phys_bits;
98 	/* CPUID returned core id bits: */
99 	__u8			x86_coreid_bits;
100 	__u8			cu_id;
101 	/* Max extended CPUID function supported: */
102 	__u32			extended_cpuid_level;
103 	/* Maximum supported CPUID level, -1=no CPUID: */
104 	int			cpuid_level;
105 	__u32			x86_capability[NCAPINTS + NBUGINTS];
106 	char			x86_vendor_id[16];
107 	char			x86_model_id[64];
108 	/* in KB - valid for CPUS which support this call: */
109 	int			x86_cache_size;
110 	int			x86_cache_alignment;	/* In bytes */
111 	/* Cache QoS architectural values: */
112 	int			x86_cache_max_rmid;	/* max index */
113 	int			x86_cache_occ_scale;	/* scale to bytes */
114 	int			x86_power;
115 	unsigned long		loops_per_jiffy;
116 	/* cpuid returned max cores value: */
117 	u16			 x86_max_cores;
118 	u16			apicid;
119 	u16			initial_apicid;
120 	u16			x86_clflush_size;
121 	/* number of cores as seen by the OS: */
122 	u16			booted_cores;
123 	/* Physical processor id: */
124 	u16			phys_proc_id;
125 	/* Logical processor id: */
126 	u16			logical_proc_id;
127 	/* Core id: */
128 	u16			cpu_core_id;
129 	/* Index into per_cpu list: */
130 	u16			cpu_index;
131 	u32			microcode;
132 } __randomize_layout;
133 
134 struct cpuid_regs {
135 	u32 eax, ebx, ecx, edx;
136 };
137 
138 enum cpuid_regs_idx {
139 	CPUID_EAX = 0,
140 	CPUID_EBX,
141 	CPUID_ECX,
142 	CPUID_EDX,
143 };
144 
145 #define X86_VENDOR_INTEL	0
146 #define X86_VENDOR_CYRIX	1
147 #define X86_VENDOR_AMD		2
148 #define X86_VENDOR_UMC		3
149 #define X86_VENDOR_CENTAUR	5
150 #define X86_VENDOR_TRANSMETA	7
151 #define X86_VENDOR_NSC		8
152 #define X86_VENDOR_NUM		9
153 
154 #define X86_VENDOR_UNKNOWN	0xff
155 
156 /*
157  * capabilities of CPUs
158  */
159 extern struct cpuinfo_x86	boot_cpu_data;
160 extern struct cpuinfo_x86	new_cpu_data;
161 
162 extern struct tss_struct	doublefault_tss;
163 extern __u32			cpu_caps_cleared[NCAPINTS];
164 extern __u32			cpu_caps_set[NCAPINTS];
165 
166 #ifdef CONFIG_SMP
167 DECLARE_PER_CPU_READ_MOSTLY(struct cpuinfo_x86, cpu_info);
168 #define cpu_data(cpu)		per_cpu(cpu_info, cpu)
169 #else
170 #define cpu_info		boot_cpu_data
171 #define cpu_data(cpu)		boot_cpu_data
172 #endif
173 
174 extern const struct seq_operations cpuinfo_op;
175 
176 #define cache_line_size()	(boot_cpu_data.x86_cache_alignment)
177 
178 extern void cpu_detect(struct cpuinfo_x86 *c);
179 
180 extern void early_cpu_init(void);
181 extern void identify_boot_cpu(void);
182 extern void identify_secondary_cpu(struct cpuinfo_x86 *);
183 extern void print_cpu_info(struct cpuinfo_x86 *);
184 void print_cpu_msr(struct cpuinfo_x86 *);
185 extern void init_scattered_cpuid_features(struct cpuinfo_x86 *c);
186 extern u32 get_scattered_cpuid_leaf(unsigned int level,
187 				    unsigned int sub_leaf,
188 				    enum cpuid_regs_idx reg);
189 extern unsigned int init_intel_cacheinfo(struct cpuinfo_x86 *c);
190 extern void init_amd_cacheinfo(struct cpuinfo_x86 *c);
191 
192 extern void detect_extended_topology(struct cpuinfo_x86 *c);
193 extern void detect_ht(struct cpuinfo_x86 *c);
194 
195 #ifdef CONFIG_X86_32
196 extern int have_cpuid_p(void);
197 #else
198 static inline int have_cpuid_p(void)
199 {
200 	return 1;
201 }
202 #endif
203 static inline void native_cpuid(unsigned int *eax, unsigned int *ebx,
204 				unsigned int *ecx, unsigned int *edx)
205 {
206 	/* ecx is often an input as well as an output. */
207 	asm volatile("cpuid"
208 	    : "=a" (*eax),
209 	      "=b" (*ebx),
210 	      "=c" (*ecx),
211 	      "=d" (*edx)
212 	    : "0" (*eax), "2" (*ecx)
213 	    : "memory");
214 }
215 
216 #define native_cpuid_reg(reg)					\
217 static inline unsigned int native_cpuid_##reg(unsigned int op)	\
218 {								\
219 	unsigned int eax = op, ebx, ecx = 0, edx;		\
220 								\
221 	native_cpuid(&eax, &ebx, &ecx, &edx);			\
222 								\
223 	return reg;						\
224 }
225 
226 /*
227  * Native CPUID functions returning a single datum.
228  */
229 native_cpuid_reg(eax)
230 native_cpuid_reg(ebx)
231 native_cpuid_reg(ecx)
232 native_cpuid_reg(edx)
233 
234 /*
235  * Friendlier CR3 helpers.
236  */
237 static inline unsigned long read_cr3_pa(void)
238 {
239 	return __read_cr3() & CR3_ADDR_MASK;
240 }
241 
242 static inline void load_cr3(pgd_t *pgdir)
243 {
244 	write_cr3(__pa(pgdir));
245 }
246 
247 #ifdef CONFIG_X86_32
248 /* This is the TSS defined by the hardware. */
249 struct x86_hw_tss {
250 	unsigned short		back_link, __blh;
251 	unsigned long		sp0;
252 	unsigned short		ss0, __ss0h;
253 	unsigned long		sp1;
254 
255 	/*
256 	 * We don't use ring 1, so ss1 is a convenient scratch space in
257 	 * the same cacheline as sp0.  We use ss1 to cache the value in
258 	 * MSR_IA32_SYSENTER_CS.  When we context switch
259 	 * MSR_IA32_SYSENTER_CS, we first check if the new value being
260 	 * written matches ss1, and, if it's not, then we wrmsr the new
261 	 * value and update ss1.
262 	 *
263 	 * The only reason we context switch MSR_IA32_SYSENTER_CS is
264 	 * that we set it to zero in vm86 tasks to avoid corrupting the
265 	 * stack if we were to go through the sysenter path from vm86
266 	 * mode.
267 	 */
268 	unsigned short		ss1;	/* MSR_IA32_SYSENTER_CS */
269 
270 	unsigned short		__ss1h;
271 	unsigned long		sp2;
272 	unsigned short		ss2, __ss2h;
273 	unsigned long		__cr3;
274 	unsigned long		ip;
275 	unsigned long		flags;
276 	unsigned long		ax;
277 	unsigned long		cx;
278 	unsigned long		dx;
279 	unsigned long		bx;
280 	unsigned long		sp;
281 	unsigned long		bp;
282 	unsigned long		si;
283 	unsigned long		di;
284 	unsigned short		es, __esh;
285 	unsigned short		cs, __csh;
286 	unsigned short		ss, __ssh;
287 	unsigned short		ds, __dsh;
288 	unsigned short		fs, __fsh;
289 	unsigned short		gs, __gsh;
290 	unsigned short		ldt, __ldth;
291 	unsigned short		trace;
292 	unsigned short		io_bitmap_base;
293 
294 } __attribute__((packed));
295 #else
296 struct x86_hw_tss {
297 	u32			reserved1;
298 	u64			sp0;
299 	u64			sp1;
300 	u64			sp2;
301 	u64			reserved2;
302 	u64			ist[7];
303 	u32			reserved3;
304 	u32			reserved4;
305 	u16			reserved5;
306 	u16			io_bitmap_base;
307 
308 } __attribute__((packed));
309 #endif
310 
311 /*
312  * IO-bitmap sizes:
313  */
314 #define IO_BITMAP_BITS			65536
315 #define IO_BITMAP_BYTES			(IO_BITMAP_BITS/8)
316 #define IO_BITMAP_LONGS			(IO_BITMAP_BYTES/sizeof(long))
317 #define IO_BITMAP_OFFSET		offsetof(struct tss_struct, io_bitmap)
318 #define INVALID_IO_BITMAP_OFFSET	0x8000
319 
320 struct tss_struct {
321 	/*
322 	 * The hardware state:
323 	 */
324 	struct x86_hw_tss	x86_tss;
325 
326 	/*
327 	 * The extra 1 is there because the CPU will access an
328 	 * additional byte beyond the end of the IO permission
329 	 * bitmap. The extra byte must be all 1 bits, and must
330 	 * be within the limit.
331 	 */
332 	unsigned long		io_bitmap[IO_BITMAP_LONGS + 1];
333 
334 #ifdef CONFIG_X86_32
335 	/*
336 	 * Space for the temporary SYSENTER stack.
337 	 */
338 	unsigned long		SYSENTER_stack_canary;
339 	unsigned long		SYSENTER_stack[64];
340 #endif
341 
342 } ____cacheline_aligned;
343 
344 DECLARE_PER_CPU_SHARED_ALIGNED(struct tss_struct, cpu_tss);
345 
346 /*
347  * sizeof(unsigned long) coming from an extra "long" at the end
348  * of the iobitmap.
349  *
350  * -1? seg base+limit should be pointing to the address of the
351  * last valid byte
352  */
353 #define __KERNEL_TSS_LIMIT	\
354 	(IO_BITMAP_OFFSET + IO_BITMAP_BYTES + sizeof(unsigned long) - 1)
355 
356 #ifdef CONFIG_X86_32
357 DECLARE_PER_CPU(unsigned long, cpu_current_top_of_stack);
358 #endif
359 
360 /*
361  * Save the original ist values for checking stack pointers during debugging
362  */
363 struct orig_ist {
364 	unsigned long		ist[7];
365 };
366 
367 #ifdef CONFIG_X86_64
368 DECLARE_PER_CPU(struct orig_ist, orig_ist);
369 
370 union irq_stack_union {
371 	char irq_stack[IRQ_STACK_SIZE];
372 	/*
373 	 * GCC hardcodes the stack canary as %gs:40.  Since the
374 	 * irq_stack is the object at %gs:0, we reserve the bottom
375 	 * 48 bytes of the irq stack for the canary.
376 	 */
377 	struct {
378 		char gs_base[40];
379 		unsigned long stack_canary;
380 	};
381 };
382 
383 DECLARE_PER_CPU_FIRST(union irq_stack_union, irq_stack_union) __visible;
384 DECLARE_INIT_PER_CPU(irq_stack_union);
385 
386 DECLARE_PER_CPU(char *, irq_stack_ptr);
387 DECLARE_PER_CPU(unsigned int, irq_count);
388 extern asmlinkage void ignore_sysret(void);
389 #else	/* X86_64 */
390 #ifdef CONFIG_CC_STACKPROTECTOR
391 /*
392  * Make sure stack canary segment base is cached-aligned:
393  *   "For Intel Atom processors, avoid non zero segment base address
394  *    that is not aligned to cache line boundary at all cost."
395  * (Optim Ref Manual Assembly/Compiler Coding Rule 15.)
396  */
397 struct stack_canary {
398 	char __pad[20];		/* canary at %gs:20 */
399 	unsigned long canary;
400 };
401 DECLARE_PER_CPU_ALIGNED(struct stack_canary, stack_canary);
402 #endif
403 /*
404  * per-CPU IRQ handling stacks
405  */
406 struct irq_stack {
407 	u32                     stack[THREAD_SIZE/sizeof(u32)];
408 } __aligned(THREAD_SIZE);
409 
410 DECLARE_PER_CPU(struct irq_stack *, hardirq_stack);
411 DECLARE_PER_CPU(struct irq_stack *, softirq_stack);
412 #endif	/* X86_64 */
413 
414 extern unsigned int fpu_kernel_xstate_size;
415 extern unsigned int fpu_user_xstate_size;
416 
417 struct perf_event;
418 
419 typedef struct {
420 	unsigned long		seg;
421 } mm_segment_t;
422 
423 struct thread_struct {
424 	/* Cached TLS descriptors: */
425 	struct desc_struct	tls_array[GDT_ENTRY_TLS_ENTRIES];
426 	unsigned long		sp0;
427 	unsigned long		sp;
428 #ifdef CONFIG_X86_32
429 	unsigned long		sysenter_cs;
430 #else
431 	unsigned short		es;
432 	unsigned short		ds;
433 	unsigned short		fsindex;
434 	unsigned short		gsindex;
435 #endif
436 
437 	u32			status;		/* thread synchronous flags */
438 
439 #ifdef CONFIG_X86_64
440 	unsigned long		fsbase;
441 	unsigned long		gsbase;
442 #else
443 	/*
444 	 * XXX: this could presumably be unsigned short.  Alternatively,
445 	 * 32-bit kernels could be taught to use fsindex instead.
446 	 */
447 	unsigned long fs;
448 	unsigned long gs;
449 #endif
450 
451 	/* Save middle states of ptrace breakpoints */
452 	struct perf_event	*ptrace_bps[HBP_NUM];
453 	/* Debug status used for traps, single steps, etc... */
454 	unsigned long           debugreg6;
455 	/* Keep track of the exact dr7 value set by the user */
456 	unsigned long           ptrace_dr7;
457 	/* Fault info: */
458 	unsigned long		cr2;
459 	unsigned long		trap_nr;
460 	unsigned long		error_code;
461 #ifdef CONFIG_VM86
462 	/* Virtual 86 mode info */
463 	struct vm86		*vm86;
464 #endif
465 	/* IO permissions: */
466 	unsigned long		*io_bitmap_ptr;
467 	unsigned long		iopl;
468 	/* Max allowed port in the bitmap, in bytes: */
469 	unsigned		io_bitmap_max;
470 
471 	mm_segment_t		addr_limit;
472 
473 	unsigned int		sig_on_uaccess_err:1;
474 	unsigned int		uaccess_err:1;	/* uaccess failed */
475 
476 	/* Floating point and extended processor state */
477 	struct fpu		fpu;
478 	/*
479 	 * WARNING: 'fpu' is dynamically-sized.  It *MUST* be at
480 	 * the end.
481 	 */
482 };
483 
484 /*
485  * Thread-synchronous status.
486  *
487  * This is different from the flags in that nobody else
488  * ever touches our thread-synchronous status, so we don't
489  * have to worry about atomic accesses.
490  */
491 #define TS_COMPAT		0x0002	/* 32bit syscall active (64BIT)*/
492 
493 /*
494  * Set IOPL bits in EFLAGS from given mask
495  */
496 static inline void native_set_iopl_mask(unsigned mask)
497 {
498 #ifdef CONFIG_X86_32
499 	unsigned int reg;
500 
501 	asm volatile ("pushfl;"
502 		      "popl %0;"
503 		      "andl %1, %0;"
504 		      "orl %2, %0;"
505 		      "pushl %0;"
506 		      "popfl"
507 		      : "=&r" (reg)
508 		      : "i" (~X86_EFLAGS_IOPL), "r" (mask));
509 #endif
510 }
511 
512 static inline void
513 native_load_sp0(struct tss_struct *tss, struct thread_struct *thread)
514 {
515 	tss->x86_tss.sp0 = thread->sp0;
516 #ifdef CONFIG_X86_32
517 	/* Only happens when SEP is enabled, no need to test "SEP"arately: */
518 	if (unlikely(tss->x86_tss.ss1 != thread->sysenter_cs)) {
519 		tss->x86_tss.ss1 = thread->sysenter_cs;
520 		wrmsr(MSR_IA32_SYSENTER_CS, thread->sysenter_cs, 0);
521 	}
522 #endif
523 }
524 
525 static inline void native_swapgs(void)
526 {
527 #ifdef CONFIG_X86_64
528 	asm volatile("swapgs" ::: "memory");
529 #endif
530 }
531 
532 static inline unsigned long current_top_of_stack(void)
533 {
534 #ifdef CONFIG_X86_64
535 	return this_cpu_read_stable(cpu_tss.x86_tss.sp0);
536 #else
537 	/* sp0 on x86_32 is special in and around vm86 mode. */
538 	return this_cpu_read_stable(cpu_current_top_of_stack);
539 #endif
540 }
541 
542 #ifdef CONFIG_PARAVIRT
543 #include <asm/paravirt.h>
544 #else
545 #define __cpuid			native_cpuid
546 
547 static inline void load_sp0(struct tss_struct *tss,
548 			    struct thread_struct *thread)
549 {
550 	native_load_sp0(tss, thread);
551 }
552 
553 #define set_iopl_mask native_set_iopl_mask
554 #endif /* CONFIG_PARAVIRT */
555 
556 /* Free all resources held by a thread. */
557 extern void release_thread(struct task_struct *);
558 
559 unsigned long get_wchan(struct task_struct *p);
560 
561 /*
562  * Generic CPUID function
563  * clear %ecx since some cpus (Cyrix MII) do not set or clear %ecx
564  * resulting in stale register contents being returned.
565  */
566 static inline void cpuid(unsigned int op,
567 			 unsigned int *eax, unsigned int *ebx,
568 			 unsigned int *ecx, unsigned int *edx)
569 {
570 	*eax = op;
571 	*ecx = 0;
572 	__cpuid(eax, ebx, ecx, edx);
573 }
574 
575 /* Some CPUID calls want 'count' to be placed in ecx */
576 static inline void cpuid_count(unsigned int op, int count,
577 			       unsigned int *eax, unsigned int *ebx,
578 			       unsigned int *ecx, unsigned int *edx)
579 {
580 	*eax = op;
581 	*ecx = count;
582 	__cpuid(eax, ebx, ecx, edx);
583 }
584 
585 /*
586  * CPUID functions returning a single datum
587  */
588 static inline unsigned int cpuid_eax(unsigned int op)
589 {
590 	unsigned int eax, ebx, ecx, edx;
591 
592 	cpuid(op, &eax, &ebx, &ecx, &edx);
593 
594 	return eax;
595 }
596 
597 static inline unsigned int cpuid_ebx(unsigned int op)
598 {
599 	unsigned int eax, ebx, ecx, edx;
600 
601 	cpuid(op, &eax, &ebx, &ecx, &edx);
602 
603 	return ebx;
604 }
605 
606 static inline unsigned int cpuid_ecx(unsigned int op)
607 {
608 	unsigned int eax, ebx, ecx, edx;
609 
610 	cpuid(op, &eax, &ebx, &ecx, &edx);
611 
612 	return ecx;
613 }
614 
615 static inline unsigned int cpuid_edx(unsigned int op)
616 {
617 	unsigned int eax, ebx, ecx, edx;
618 
619 	cpuid(op, &eax, &ebx, &ecx, &edx);
620 
621 	return edx;
622 }
623 
624 /* REP NOP (PAUSE) is a good thing to insert into busy-wait loops. */
625 static __always_inline void rep_nop(void)
626 {
627 	asm volatile("rep; nop" ::: "memory");
628 }
629 
630 static __always_inline void cpu_relax(void)
631 {
632 	rep_nop();
633 }
634 
635 /*
636  * This function forces the icache and prefetched instruction stream to
637  * catch up with reality in two very specific cases:
638  *
639  *  a) Text was modified using one virtual address and is about to be executed
640  *     from the same physical page at a different virtual address.
641  *
642  *  b) Text was modified on a different CPU, may subsequently be
643  *     executed on this CPU, and you want to make sure the new version
644  *     gets executed.  This generally means you're calling this in a IPI.
645  *
646  * If you're calling this for a different reason, you're probably doing
647  * it wrong.
648  */
649 static inline void sync_core(void)
650 {
651 	/*
652 	 * There are quite a few ways to do this.  IRET-to-self is nice
653 	 * because it works on every CPU, at any CPL (so it's compatible
654 	 * with paravirtualization), and it never exits to a hypervisor.
655 	 * The only down sides are that it's a bit slow (it seems to be
656 	 * a bit more than 2x slower than the fastest options) and that
657 	 * it unmasks NMIs.  The "push %cs" is needed because, in
658 	 * paravirtual environments, __KERNEL_CS may not be a valid CS
659 	 * value when we do IRET directly.
660 	 *
661 	 * In case NMI unmasking or performance ever becomes a problem,
662 	 * the next best option appears to be MOV-to-CR2 and an
663 	 * unconditional jump.  That sequence also works on all CPUs,
664 	 * but it will fault at CPL3 (i.e. Xen PV and lguest).
665 	 *
666 	 * CPUID is the conventional way, but it's nasty: it doesn't
667 	 * exist on some 486-like CPUs, and it usually exits to a
668 	 * hypervisor.
669 	 *
670 	 * Like all of Linux's memory ordering operations, this is a
671 	 * compiler barrier as well.
672 	 */
673 	register void *__sp asm(_ASM_SP);
674 
675 #ifdef CONFIG_X86_32
676 	asm volatile (
677 		"pushfl\n\t"
678 		"pushl %%cs\n\t"
679 		"pushl $1f\n\t"
680 		"iret\n\t"
681 		"1:"
682 		: "+r" (__sp) : : "memory");
683 #else
684 	unsigned int tmp;
685 
686 	asm volatile (
687 		"mov %%ss, %0\n\t"
688 		"pushq %q0\n\t"
689 		"pushq %%rsp\n\t"
690 		"addq $8, (%%rsp)\n\t"
691 		"pushfq\n\t"
692 		"mov %%cs, %0\n\t"
693 		"pushq %q0\n\t"
694 		"pushq $1f\n\t"
695 		"iretq\n\t"
696 		"1:"
697 		: "=&r" (tmp), "+r" (__sp) : : "cc", "memory");
698 #endif
699 }
700 
701 extern void select_idle_routine(const struct cpuinfo_x86 *c);
702 extern void amd_e400_c1e_apic_setup(void);
703 
704 extern unsigned long		boot_option_idle_override;
705 
706 enum idle_boot_override {IDLE_NO_OVERRIDE=0, IDLE_HALT, IDLE_NOMWAIT,
707 			 IDLE_POLL};
708 
709 extern void enable_sep_cpu(void);
710 extern int sysenter_setup(void);
711 
712 extern void early_trap_init(void);
713 void early_trap_pf_init(void);
714 
715 /* Defined in head.S */
716 extern struct desc_ptr		early_gdt_descr;
717 
718 extern void cpu_set_gdt(int);
719 extern void switch_to_new_gdt(int);
720 extern void load_direct_gdt(int);
721 extern void load_fixmap_gdt(int);
722 extern void load_percpu_segment(int);
723 extern void cpu_init(void);
724 
725 static inline unsigned long get_debugctlmsr(void)
726 {
727 	unsigned long debugctlmsr = 0;
728 
729 #ifndef CONFIG_X86_DEBUGCTLMSR
730 	if (boot_cpu_data.x86 < 6)
731 		return 0;
732 #endif
733 	rdmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
734 
735 	return debugctlmsr;
736 }
737 
738 static inline void update_debugctlmsr(unsigned long debugctlmsr)
739 {
740 #ifndef CONFIG_X86_DEBUGCTLMSR
741 	if (boot_cpu_data.x86 < 6)
742 		return;
743 #endif
744 	wrmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
745 }
746 
747 extern void set_task_blockstep(struct task_struct *task, bool on);
748 
749 /* Boot loader type from the setup header: */
750 extern int			bootloader_type;
751 extern int			bootloader_version;
752 
753 extern char			ignore_fpu_irq;
754 
755 #define HAVE_ARCH_PICK_MMAP_LAYOUT 1
756 #define ARCH_HAS_PREFETCHW
757 #define ARCH_HAS_SPINLOCK_PREFETCH
758 
759 #ifdef CONFIG_X86_32
760 # define BASE_PREFETCH		""
761 # define ARCH_HAS_PREFETCH
762 #else
763 # define BASE_PREFETCH		"prefetcht0 %P1"
764 #endif
765 
766 /*
767  * Prefetch instructions for Pentium III (+) and AMD Athlon (+)
768  *
769  * It's not worth to care about 3dnow prefetches for the K6
770  * because they are microcoded there and very slow.
771  */
772 static inline void prefetch(const void *x)
773 {
774 	alternative_input(BASE_PREFETCH, "prefetchnta %P1",
775 			  X86_FEATURE_XMM,
776 			  "m" (*(const char *)x));
777 }
778 
779 /*
780  * 3dnow prefetch to get an exclusive cache line.
781  * Useful for spinlocks to avoid one state transition in the
782  * cache coherency protocol:
783  */
784 static inline void prefetchw(const void *x)
785 {
786 	alternative_input(BASE_PREFETCH, "prefetchw %P1",
787 			  X86_FEATURE_3DNOWPREFETCH,
788 			  "m" (*(const char *)x));
789 }
790 
791 static inline void spin_lock_prefetch(const void *x)
792 {
793 	prefetchw(x);
794 }
795 
796 #define TOP_OF_INIT_STACK ((unsigned long)&init_stack + sizeof(init_stack) - \
797 			   TOP_OF_KERNEL_STACK_PADDING)
798 
799 #ifdef CONFIG_X86_32
800 /*
801  * User space process size: 3GB (default).
802  */
803 #define IA32_PAGE_OFFSET	PAGE_OFFSET
804 #define TASK_SIZE		PAGE_OFFSET
805 #define TASK_SIZE_MAX		TASK_SIZE
806 #define STACK_TOP		TASK_SIZE
807 #define STACK_TOP_MAX		STACK_TOP
808 
809 #define INIT_THREAD  {							  \
810 	.sp0			= TOP_OF_INIT_STACK,			  \
811 	.sysenter_cs		= __KERNEL_CS,				  \
812 	.io_bitmap_ptr		= NULL,					  \
813 	.addr_limit		= KERNEL_DS,				  \
814 }
815 
816 /*
817  * TOP_OF_KERNEL_STACK_PADDING reserves 8 bytes on top of the ring0 stack.
818  * This is necessary to guarantee that the entire "struct pt_regs"
819  * is accessible even if the CPU haven't stored the SS/ESP registers
820  * on the stack (interrupt gate does not save these registers
821  * when switching to the same priv ring).
822  * Therefore beware: accessing the ss/esp fields of the
823  * "struct pt_regs" is possible, but they may contain the
824  * completely wrong values.
825  */
826 #define task_pt_regs(task) \
827 ({									\
828 	unsigned long __ptr = (unsigned long)task_stack_page(task);	\
829 	__ptr += THREAD_SIZE - TOP_OF_KERNEL_STACK_PADDING;		\
830 	((struct pt_regs *)__ptr) - 1;					\
831 })
832 
833 #define KSTK_ESP(task)		(task_pt_regs(task)->sp)
834 
835 #else
836 /*
837  * User space process size. 47bits minus one guard page.  The guard
838  * page is necessary on Intel CPUs: if a SYSCALL instruction is at
839  * the highest possible canonical userspace address, then that
840  * syscall will enter the kernel with a non-canonical return
841  * address, and SYSRET will explode dangerously.  We avoid this
842  * particular problem by preventing anything from being mapped
843  * at the maximum canonical address.
844  */
845 #define TASK_SIZE_MAX	((1UL << 47) - PAGE_SIZE)
846 
847 /* This decides where the kernel will search for a free chunk of vm
848  * space during mmap's.
849  */
850 #define IA32_PAGE_OFFSET	((current->personality & ADDR_LIMIT_3GB) ? \
851 					0xc0000000 : 0xFFFFe000)
852 
853 #define TASK_SIZE		(test_thread_flag(TIF_ADDR32) ? \
854 					IA32_PAGE_OFFSET : TASK_SIZE_MAX)
855 #define TASK_SIZE_OF(child)	((test_tsk_thread_flag(child, TIF_ADDR32)) ? \
856 					IA32_PAGE_OFFSET : TASK_SIZE_MAX)
857 
858 #define STACK_TOP		TASK_SIZE
859 #define STACK_TOP_MAX		TASK_SIZE_MAX
860 
861 #define INIT_THREAD  {						\
862 	.sp0			= TOP_OF_INIT_STACK,		\
863 	.addr_limit		= KERNEL_DS,			\
864 }
865 
866 #define task_pt_regs(tsk)	((struct pt_regs *)(tsk)->thread.sp0 - 1)
867 extern unsigned long KSTK_ESP(struct task_struct *task);
868 
869 #endif /* CONFIG_X86_64 */
870 
871 extern void start_thread(struct pt_regs *regs, unsigned long new_ip,
872 					       unsigned long new_sp);
873 
874 /*
875  * This decides where the kernel will search for a free chunk of vm
876  * space during mmap's.
877  */
878 #define __TASK_UNMAPPED_BASE(task_size)	(PAGE_ALIGN(task_size / 3))
879 #define TASK_UNMAPPED_BASE		__TASK_UNMAPPED_BASE(TASK_SIZE)
880 
881 #define KSTK_EIP(task)		(task_pt_regs(task)->ip)
882 
883 /* Get/set a process' ability to use the timestamp counter instruction */
884 #define GET_TSC_CTL(adr)	get_tsc_mode((adr))
885 #define SET_TSC_CTL(val)	set_tsc_mode((val))
886 
887 extern int get_tsc_mode(unsigned long adr);
888 extern int set_tsc_mode(unsigned int val);
889 
890 DECLARE_PER_CPU(u64, msr_misc_features_shadow);
891 
892 /* Register/unregister a process' MPX related resource */
893 #define MPX_ENABLE_MANAGEMENT()	mpx_enable_management()
894 #define MPX_DISABLE_MANAGEMENT()	mpx_disable_management()
895 
896 #ifdef CONFIG_X86_INTEL_MPX
897 extern int mpx_enable_management(void);
898 extern int mpx_disable_management(void);
899 #else
900 static inline int mpx_enable_management(void)
901 {
902 	return -EINVAL;
903 }
904 static inline int mpx_disable_management(void)
905 {
906 	return -EINVAL;
907 }
908 #endif /* CONFIG_X86_INTEL_MPX */
909 
910 #ifdef CONFIG_CPU_SUP_AMD
911 extern u16 amd_get_nb_id(int cpu);
912 extern u32 amd_get_nodes_per_socket(void);
913 #else
914 static inline u16 amd_get_nb_id(int cpu)		{ return 0; }
915 static inline u32 amd_get_nodes_per_socket(void)	{ return 0; }
916 #endif
917 
918 static inline uint32_t hypervisor_cpuid_base(const char *sig, uint32_t leaves)
919 {
920 	uint32_t base, eax, signature[3];
921 
922 	for (base = 0x40000000; base < 0x40010000; base += 0x100) {
923 		cpuid(base, &eax, &signature[0], &signature[1], &signature[2]);
924 
925 		if (!memcmp(sig, signature, 12) &&
926 		    (leaves == 0 || ((eax - base) >= leaves)))
927 			return base;
928 	}
929 
930 	return 0;
931 }
932 
933 extern unsigned long arch_align_stack(unsigned long sp);
934 extern void free_init_pages(char *what, unsigned long begin, unsigned long end);
935 
936 void default_idle(void);
937 #ifdef	CONFIG_XEN
938 bool xen_set_default_idle(void);
939 #else
940 #define xen_set_default_idle 0
941 #endif
942 
943 void stop_this_cpu(void *dummy);
944 void df_debug(struct pt_regs *regs, long error_code);
945 #endif /* _ASM_X86_PROCESSOR_H */
946