xref: /openbmc/linux/arch/x86/include/asm/processor.h (revision f71a261a)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_PROCESSOR_H
3 #define _ASM_X86_PROCESSOR_H
4 
5 #include <asm/processor-flags.h>
6 
7 /* Forward declaration, a strange C thing */
8 struct task_struct;
9 struct mm_struct;
10 struct io_bitmap;
11 struct vm86;
12 
13 #include <asm/math_emu.h>
14 #include <asm/segment.h>
15 #include <asm/types.h>
16 #include <uapi/asm/sigcontext.h>
17 #include <asm/current.h>
18 #include <asm/cpufeatures.h>
19 #include <asm/page.h>
20 #include <asm/pgtable_types.h>
21 #include <asm/percpu.h>
22 #include <asm/msr.h>
23 #include <asm/desc_defs.h>
24 #include <asm/nops.h>
25 #include <asm/special_insns.h>
26 #include <asm/fpu/types.h>
27 #include <asm/unwind_hints.h>
28 #include <asm/vmxfeatures.h>
29 #include <asm/vdso/processor.h>
30 
31 #include <linux/personality.h>
32 #include <linux/cache.h>
33 #include <linux/threads.h>
34 #include <linux/math64.h>
35 #include <linux/err.h>
36 #include <linux/irqflags.h>
37 #include <linux/mem_encrypt.h>
38 
39 /*
40  * We handle most unaligned accesses in hardware.  On the other hand
41  * unaligned DMA can be quite expensive on some Nehalem processors.
42  *
43  * Based on this we disable the IP header alignment in network drivers.
44  */
45 #define NET_IP_ALIGN	0
46 
47 #define HBP_NUM 4
48 
49 /*
50  * These alignment constraints are for performance in the vSMP case,
51  * but in the task_struct case we must also meet hardware imposed
52  * alignment requirements of the FPU state:
53  */
54 #ifdef CONFIG_X86_VSMP
55 # define ARCH_MIN_TASKALIGN		(1 << INTERNODE_CACHE_SHIFT)
56 # define ARCH_MIN_MMSTRUCT_ALIGN	(1 << INTERNODE_CACHE_SHIFT)
57 #else
58 # define ARCH_MIN_TASKALIGN		__alignof__(union fpregs_state)
59 # define ARCH_MIN_MMSTRUCT_ALIGN	0
60 #endif
61 
62 enum tlb_infos {
63 	ENTRIES,
64 	NR_INFO
65 };
66 
67 extern u16 __read_mostly tlb_lli_4k[NR_INFO];
68 extern u16 __read_mostly tlb_lli_2m[NR_INFO];
69 extern u16 __read_mostly tlb_lli_4m[NR_INFO];
70 extern u16 __read_mostly tlb_lld_4k[NR_INFO];
71 extern u16 __read_mostly tlb_lld_2m[NR_INFO];
72 extern u16 __read_mostly tlb_lld_4m[NR_INFO];
73 extern u16 __read_mostly tlb_lld_1g[NR_INFO];
74 
75 /*
76  *  CPU type and hardware bug flags. Kept separately for each CPU.
77  *  Members of this structure are referenced in head_32.S, so think twice
78  *  before touching them. [mj]
79  */
80 
81 struct cpuinfo_x86 {
82 	__u8			x86;		/* CPU family */
83 	__u8			x86_vendor;	/* CPU vendor */
84 	__u8			x86_model;
85 	__u8			x86_stepping;
86 #ifdef CONFIG_X86_64
87 	/* Number of 4K pages in DTLB/ITLB combined(in pages): */
88 	int			x86_tlbsize;
89 #endif
90 #ifdef CONFIG_X86_VMX_FEATURE_NAMES
91 	__u32			vmx_capability[NVMXINTS];
92 #endif
93 	__u8			x86_virt_bits;
94 	__u8			x86_phys_bits;
95 	/* CPUID returned core id bits: */
96 	__u8			x86_coreid_bits;
97 	__u8			cu_id;
98 	/* Max extended CPUID function supported: */
99 	__u32			extended_cpuid_level;
100 	/* Maximum supported CPUID level, -1=no CPUID: */
101 	int			cpuid_level;
102 	/*
103 	 * Align to size of unsigned long because the x86_capability array
104 	 * is passed to bitops which require the alignment. Use unnamed
105 	 * union to enforce the array is aligned to size of unsigned long.
106 	 */
107 	union {
108 		__u32		x86_capability[NCAPINTS + NBUGINTS];
109 		unsigned long	x86_capability_alignment;
110 	};
111 	char			x86_vendor_id[16];
112 	char			x86_model_id[64];
113 	/* in KB - valid for CPUS which support this call: */
114 	unsigned int		x86_cache_size;
115 	int			x86_cache_alignment;	/* In bytes */
116 	/* Cache QoS architectural values, valid only on the BSP: */
117 	int			x86_cache_max_rmid;	/* max index */
118 	int			x86_cache_occ_scale;	/* scale to bytes */
119 	int			x86_cache_mbm_width_offset;
120 	int			x86_power;
121 	unsigned long		loops_per_jiffy;
122 	/* protected processor identification number */
123 	u64			ppin;
124 	/* cpuid returned max cores value: */
125 	u16			x86_max_cores;
126 	u16			apicid;
127 	u16			initial_apicid;
128 	u16			x86_clflush_size;
129 	/* number of cores as seen by the OS: */
130 	u16			booted_cores;
131 	/* Physical processor id: */
132 	u16			phys_proc_id;
133 	/* Logical processor id: */
134 	u16			logical_proc_id;
135 	/* Core id: */
136 	u16			cpu_core_id;
137 	u16			cpu_die_id;
138 	u16			logical_die_id;
139 	/* Index into per_cpu list: */
140 	u16			cpu_index;
141 	/*  Is SMT active on this core? */
142 	bool			smt_active;
143 	u32			microcode;
144 	/* Address space bits used by the cache internally */
145 	u8			x86_cache_bits;
146 	unsigned		initialized : 1;
147 } __randomize_layout;
148 
149 struct cpuid_regs {
150 	u32 eax, ebx, ecx, edx;
151 };
152 
153 enum cpuid_regs_idx {
154 	CPUID_EAX = 0,
155 	CPUID_EBX,
156 	CPUID_ECX,
157 	CPUID_EDX,
158 };
159 
160 #define X86_VENDOR_INTEL	0
161 #define X86_VENDOR_CYRIX	1
162 #define X86_VENDOR_AMD		2
163 #define X86_VENDOR_UMC		3
164 #define X86_VENDOR_CENTAUR	5
165 #define X86_VENDOR_TRANSMETA	7
166 #define X86_VENDOR_NSC		8
167 #define X86_VENDOR_HYGON	9
168 #define X86_VENDOR_ZHAOXIN	10
169 #define X86_VENDOR_VORTEX	11
170 #define X86_VENDOR_NUM		12
171 
172 #define X86_VENDOR_UNKNOWN	0xff
173 
174 /*
175  * capabilities of CPUs
176  */
177 extern struct cpuinfo_x86	boot_cpu_data;
178 extern struct cpuinfo_x86	new_cpu_data;
179 
180 extern __u32			cpu_caps_cleared[NCAPINTS + NBUGINTS];
181 extern __u32			cpu_caps_set[NCAPINTS + NBUGINTS];
182 
183 #ifdef CONFIG_SMP
184 DECLARE_PER_CPU_READ_MOSTLY(struct cpuinfo_x86, cpu_info);
185 #define cpu_data(cpu)		per_cpu(cpu_info, cpu)
186 #else
187 #define cpu_info		boot_cpu_data
188 #define cpu_data(cpu)		boot_cpu_data
189 #endif
190 
191 extern const struct seq_operations cpuinfo_op;
192 
193 #define cache_line_size()	(boot_cpu_data.x86_cache_alignment)
194 
195 extern void cpu_detect(struct cpuinfo_x86 *c);
196 
197 static inline unsigned long long l1tf_pfn_limit(void)
198 {
199 	return BIT_ULL(boot_cpu_data.x86_cache_bits - 1 - PAGE_SHIFT);
200 }
201 
202 extern void early_cpu_init(void);
203 extern void identify_boot_cpu(void);
204 extern void identify_secondary_cpu(struct cpuinfo_x86 *);
205 extern void print_cpu_info(struct cpuinfo_x86 *);
206 void print_cpu_msr(struct cpuinfo_x86 *);
207 
208 #ifdef CONFIG_X86_32
209 extern int have_cpuid_p(void);
210 #else
211 static inline int have_cpuid_p(void)
212 {
213 	return 1;
214 }
215 #endif
216 static inline void native_cpuid(unsigned int *eax, unsigned int *ebx,
217 				unsigned int *ecx, unsigned int *edx)
218 {
219 	/* ecx is often an input as well as an output. */
220 	asm volatile("cpuid"
221 	    : "=a" (*eax),
222 	      "=b" (*ebx),
223 	      "=c" (*ecx),
224 	      "=d" (*edx)
225 	    : "0" (*eax), "2" (*ecx)
226 	    : "memory");
227 }
228 
229 #define native_cpuid_reg(reg)					\
230 static inline unsigned int native_cpuid_##reg(unsigned int op)	\
231 {								\
232 	unsigned int eax = op, ebx, ecx = 0, edx;		\
233 								\
234 	native_cpuid(&eax, &ebx, &ecx, &edx);			\
235 								\
236 	return reg;						\
237 }
238 
239 /*
240  * Native CPUID functions returning a single datum.
241  */
242 native_cpuid_reg(eax)
243 native_cpuid_reg(ebx)
244 native_cpuid_reg(ecx)
245 native_cpuid_reg(edx)
246 
247 /*
248  * Friendlier CR3 helpers.
249  */
250 static inline unsigned long read_cr3_pa(void)
251 {
252 	return __read_cr3() & CR3_ADDR_MASK;
253 }
254 
255 static inline unsigned long native_read_cr3_pa(void)
256 {
257 	return __native_read_cr3() & CR3_ADDR_MASK;
258 }
259 
260 static inline void load_cr3(pgd_t *pgdir)
261 {
262 	write_cr3(__sme_pa(pgdir));
263 }
264 
265 /*
266  * Note that while the legacy 'TSS' name comes from 'Task State Segment',
267  * on modern x86 CPUs the TSS also holds information important to 64-bit mode,
268  * unrelated to the task-switch mechanism:
269  */
270 #ifdef CONFIG_X86_32
271 /* This is the TSS defined by the hardware. */
272 struct x86_hw_tss {
273 	unsigned short		back_link, __blh;
274 	unsigned long		sp0;
275 	unsigned short		ss0, __ss0h;
276 	unsigned long		sp1;
277 
278 	/*
279 	 * We don't use ring 1, so ss1 is a convenient scratch space in
280 	 * the same cacheline as sp0.  We use ss1 to cache the value in
281 	 * MSR_IA32_SYSENTER_CS.  When we context switch
282 	 * MSR_IA32_SYSENTER_CS, we first check if the new value being
283 	 * written matches ss1, and, if it's not, then we wrmsr the new
284 	 * value and update ss1.
285 	 *
286 	 * The only reason we context switch MSR_IA32_SYSENTER_CS is
287 	 * that we set it to zero in vm86 tasks to avoid corrupting the
288 	 * stack if we were to go through the sysenter path from vm86
289 	 * mode.
290 	 */
291 	unsigned short		ss1;	/* MSR_IA32_SYSENTER_CS */
292 
293 	unsigned short		__ss1h;
294 	unsigned long		sp2;
295 	unsigned short		ss2, __ss2h;
296 	unsigned long		__cr3;
297 	unsigned long		ip;
298 	unsigned long		flags;
299 	unsigned long		ax;
300 	unsigned long		cx;
301 	unsigned long		dx;
302 	unsigned long		bx;
303 	unsigned long		sp;
304 	unsigned long		bp;
305 	unsigned long		si;
306 	unsigned long		di;
307 	unsigned short		es, __esh;
308 	unsigned short		cs, __csh;
309 	unsigned short		ss, __ssh;
310 	unsigned short		ds, __dsh;
311 	unsigned short		fs, __fsh;
312 	unsigned short		gs, __gsh;
313 	unsigned short		ldt, __ldth;
314 	unsigned short		trace;
315 	unsigned short		io_bitmap_base;
316 
317 } __attribute__((packed));
318 #else
319 struct x86_hw_tss {
320 	u32			reserved1;
321 	u64			sp0;
322 	u64			sp1;
323 
324 	/*
325 	 * Since Linux does not use ring 2, the 'sp2' slot is unused by
326 	 * hardware.  entry_SYSCALL_64 uses it as scratch space to stash
327 	 * the user RSP value.
328 	 */
329 	u64			sp2;
330 
331 	u64			reserved2;
332 	u64			ist[7];
333 	u32			reserved3;
334 	u32			reserved4;
335 	u16			reserved5;
336 	u16			io_bitmap_base;
337 
338 } __attribute__((packed));
339 #endif
340 
341 /*
342  * IO-bitmap sizes:
343  */
344 #define IO_BITMAP_BITS			65536
345 #define IO_BITMAP_BYTES			(IO_BITMAP_BITS / BITS_PER_BYTE)
346 #define IO_BITMAP_LONGS			(IO_BITMAP_BYTES / sizeof(long))
347 
348 #define IO_BITMAP_OFFSET_VALID_MAP				\
349 	(offsetof(struct tss_struct, io_bitmap.bitmap) -	\
350 	 offsetof(struct tss_struct, x86_tss))
351 
352 #define IO_BITMAP_OFFSET_VALID_ALL				\
353 	(offsetof(struct tss_struct, io_bitmap.mapall) -	\
354 	 offsetof(struct tss_struct, x86_tss))
355 
356 #ifdef CONFIG_X86_IOPL_IOPERM
357 /*
358  * sizeof(unsigned long) coming from an extra "long" at the end of the
359  * iobitmap. The limit is inclusive, i.e. the last valid byte.
360  */
361 # define __KERNEL_TSS_LIMIT	\
362 	(IO_BITMAP_OFFSET_VALID_ALL + IO_BITMAP_BYTES + \
363 	 sizeof(unsigned long) - 1)
364 #else
365 # define __KERNEL_TSS_LIMIT	\
366 	(offsetof(struct tss_struct, x86_tss) + sizeof(struct x86_hw_tss) - 1)
367 #endif
368 
369 /* Base offset outside of TSS_LIMIT so unpriviledged IO causes #GP */
370 #define IO_BITMAP_OFFSET_INVALID	(__KERNEL_TSS_LIMIT + 1)
371 
372 struct entry_stack {
373 	char	stack[PAGE_SIZE];
374 };
375 
376 struct entry_stack_page {
377 	struct entry_stack stack;
378 } __aligned(PAGE_SIZE);
379 
380 /*
381  * All IO bitmap related data stored in the TSS:
382  */
383 struct x86_io_bitmap {
384 	/* The sequence number of the last active bitmap. */
385 	u64			prev_sequence;
386 
387 	/*
388 	 * Store the dirty size of the last io bitmap offender. The next
389 	 * one will have to do the cleanup as the switch out to a non io
390 	 * bitmap user will just set x86_tss.io_bitmap_base to a value
391 	 * outside of the TSS limit. So for sane tasks there is no need to
392 	 * actually touch the io_bitmap at all.
393 	 */
394 	unsigned int		prev_max;
395 
396 	/*
397 	 * The extra 1 is there because the CPU will access an
398 	 * additional byte beyond the end of the IO permission
399 	 * bitmap. The extra byte must be all 1 bits, and must
400 	 * be within the limit.
401 	 */
402 	unsigned long		bitmap[IO_BITMAP_LONGS + 1];
403 
404 	/*
405 	 * Special I/O bitmap to emulate IOPL(3). All bytes zero,
406 	 * except the additional byte at the end.
407 	 */
408 	unsigned long		mapall[IO_BITMAP_LONGS + 1];
409 };
410 
411 struct tss_struct {
412 	/*
413 	 * The fixed hardware portion.  This must not cross a page boundary
414 	 * at risk of violating the SDM's advice and potentially triggering
415 	 * errata.
416 	 */
417 	struct x86_hw_tss	x86_tss;
418 
419 	struct x86_io_bitmap	io_bitmap;
420 } __aligned(PAGE_SIZE);
421 
422 DECLARE_PER_CPU_PAGE_ALIGNED(struct tss_struct, cpu_tss_rw);
423 
424 /* Per CPU interrupt stacks */
425 struct irq_stack {
426 	char		stack[IRQ_STACK_SIZE];
427 } __aligned(IRQ_STACK_SIZE);
428 
429 DECLARE_PER_CPU(unsigned long, cpu_current_top_of_stack);
430 
431 #ifdef CONFIG_X86_64
432 struct fixed_percpu_data {
433 	/*
434 	 * GCC hardcodes the stack canary as %gs:40.  Since the
435 	 * irq_stack is the object at %gs:0, we reserve the bottom
436 	 * 48 bytes of the irq stack for the canary.
437 	 *
438 	 * Once we are willing to require -mstack-protector-guard-symbol=
439 	 * support for x86_64 stackprotector, we can get rid of this.
440 	 */
441 	char		gs_base[40];
442 	unsigned long	stack_canary;
443 };
444 
445 DECLARE_PER_CPU_FIRST(struct fixed_percpu_data, fixed_percpu_data) __visible;
446 DECLARE_INIT_PER_CPU(fixed_percpu_data);
447 
448 static inline unsigned long cpu_kernelmode_gs_base(int cpu)
449 {
450 	return (unsigned long)per_cpu(fixed_percpu_data.gs_base, cpu);
451 }
452 
453 DECLARE_PER_CPU(void *, hardirq_stack_ptr);
454 DECLARE_PER_CPU(bool, hardirq_stack_inuse);
455 extern asmlinkage void ignore_sysret(void);
456 
457 /* Save actual FS/GS selectors and bases to current->thread */
458 void current_save_fsgs(void);
459 #else	/* X86_64 */
460 #ifdef CONFIG_STACKPROTECTOR
461 DECLARE_PER_CPU(unsigned long, __stack_chk_guard);
462 #endif
463 DECLARE_PER_CPU(struct irq_stack *, hardirq_stack_ptr);
464 DECLARE_PER_CPU(struct irq_stack *, softirq_stack_ptr);
465 #endif	/* !X86_64 */
466 
467 struct perf_event;
468 
469 struct thread_struct {
470 	/* Cached TLS descriptors: */
471 	struct desc_struct	tls_array[GDT_ENTRY_TLS_ENTRIES];
472 #ifdef CONFIG_X86_32
473 	unsigned long		sp0;
474 #endif
475 	unsigned long		sp;
476 #ifdef CONFIG_X86_32
477 	unsigned long		sysenter_cs;
478 #else
479 	unsigned short		es;
480 	unsigned short		ds;
481 	unsigned short		fsindex;
482 	unsigned short		gsindex;
483 #endif
484 
485 #ifdef CONFIG_X86_64
486 	unsigned long		fsbase;
487 	unsigned long		gsbase;
488 #else
489 	/*
490 	 * XXX: this could presumably be unsigned short.  Alternatively,
491 	 * 32-bit kernels could be taught to use fsindex instead.
492 	 */
493 	unsigned long fs;
494 	unsigned long gs;
495 #endif
496 
497 	/* Save middle states of ptrace breakpoints */
498 	struct perf_event	*ptrace_bps[HBP_NUM];
499 	/* Debug status used for traps, single steps, etc... */
500 	unsigned long           virtual_dr6;
501 	/* Keep track of the exact dr7 value set by the user */
502 	unsigned long           ptrace_dr7;
503 	/* Fault info: */
504 	unsigned long		cr2;
505 	unsigned long		trap_nr;
506 	unsigned long		error_code;
507 #ifdef CONFIG_VM86
508 	/* Virtual 86 mode info */
509 	struct vm86		*vm86;
510 #endif
511 	/* IO permissions: */
512 	struct io_bitmap	*io_bitmap;
513 
514 	/*
515 	 * IOPL. Privilege level dependent I/O permission which is
516 	 * emulated via the I/O bitmap to prevent user space from disabling
517 	 * interrupts.
518 	 */
519 	unsigned long		iopl_emul;
520 
521 	unsigned int		iopl_warn:1;
522 	unsigned int		sig_on_uaccess_err:1;
523 
524 	/*
525 	 * Protection Keys Register for Userspace.  Loaded immediately on
526 	 * context switch. Store it in thread_struct to avoid a lookup in
527 	 * the tasks's FPU xstate buffer. This value is only valid when a
528 	 * task is scheduled out. For 'current' the authoritative source of
529 	 * PKRU is the hardware itself.
530 	 */
531 	u32			pkru;
532 
533 	/* Floating point and extended processor state */
534 	struct fpu		fpu;
535 	/*
536 	 * WARNING: 'fpu' is dynamically-sized.  It *MUST* be at
537 	 * the end.
538 	 */
539 };
540 
541 extern void fpu_thread_struct_whitelist(unsigned long *offset, unsigned long *size);
542 
543 static inline void arch_thread_struct_whitelist(unsigned long *offset,
544 						unsigned long *size)
545 {
546 	fpu_thread_struct_whitelist(offset, size);
547 }
548 
549 static inline void
550 native_load_sp0(unsigned long sp0)
551 {
552 	this_cpu_write(cpu_tss_rw.x86_tss.sp0, sp0);
553 }
554 
555 static __always_inline void native_swapgs(void)
556 {
557 #ifdef CONFIG_X86_64
558 	asm volatile("swapgs" ::: "memory");
559 #endif
560 }
561 
562 static inline unsigned long current_top_of_stack(void)
563 {
564 	/*
565 	 *  We can't read directly from tss.sp0: sp0 on x86_32 is special in
566 	 *  and around vm86 mode and sp0 on x86_64 is special because of the
567 	 *  entry trampoline.
568 	 */
569 	return this_cpu_read_stable(cpu_current_top_of_stack);
570 }
571 
572 static inline bool on_thread_stack(void)
573 {
574 	return (unsigned long)(current_top_of_stack() -
575 			       current_stack_pointer) < THREAD_SIZE;
576 }
577 
578 #ifdef CONFIG_PARAVIRT_XXL
579 #include <asm/paravirt.h>
580 #else
581 #define __cpuid			native_cpuid
582 
583 static inline void load_sp0(unsigned long sp0)
584 {
585 	native_load_sp0(sp0);
586 }
587 
588 #endif /* CONFIG_PARAVIRT_XXL */
589 
590 /* Free all resources held by a thread. */
591 extern void release_thread(struct task_struct *);
592 
593 unsigned long __get_wchan(struct task_struct *p);
594 
595 /*
596  * Generic CPUID function
597  * clear %ecx since some cpus (Cyrix MII) do not set or clear %ecx
598  * resulting in stale register contents being returned.
599  */
600 static inline void cpuid(unsigned int op,
601 			 unsigned int *eax, unsigned int *ebx,
602 			 unsigned int *ecx, unsigned int *edx)
603 {
604 	*eax = op;
605 	*ecx = 0;
606 	__cpuid(eax, ebx, ecx, edx);
607 }
608 
609 /* Some CPUID calls want 'count' to be placed in ecx */
610 static inline void cpuid_count(unsigned int op, int count,
611 			       unsigned int *eax, unsigned int *ebx,
612 			       unsigned int *ecx, unsigned int *edx)
613 {
614 	*eax = op;
615 	*ecx = count;
616 	__cpuid(eax, ebx, ecx, edx);
617 }
618 
619 /*
620  * CPUID functions returning a single datum
621  */
622 static inline unsigned int cpuid_eax(unsigned int op)
623 {
624 	unsigned int eax, ebx, ecx, edx;
625 
626 	cpuid(op, &eax, &ebx, &ecx, &edx);
627 
628 	return eax;
629 }
630 
631 static inline unsigned int cpuid_ebx(unsigned int op)
632 {
633 	unsigned int eax, ebx, ecx, edx;
634 
635 	cpuid(op, &eax, &ebx, &ecx, &edx);
636 
637 	return ebx;
638 }
639 
640 static inline unsigned int cpuid_ecx(unsigned int op)
641 {
642 	unsigned int eax, ebx, ecx, edx;
643 
644 	cpuid(op, &eax, &ebx, &ecx, &edx);
645 
646 	return ecx;
647 }
648 
649 static inline unsigned int cpuid_edx(unsigned int op)
650 {
651 	unsigned int eax, ebx, ecx, edx;
652 
653 	cpuid(op, &eax, &ebx, &ecx, &edx);
654 
655 	return edx;
656 }
657 
658 extern void select_idle_routine(const struct cpuinfo_x86 *c);
659 extern void amd_e400_c1e_apic_setup(void);
660 
661 extern unsigned long		boot_option_idle_override;
662 
663 enum idle_boot_override {IDLE_NO_OVERRIDE=0, IDLE_HALT, IDLE_NOMWAIT,
664 			 IDLE_POLL};
665 
666 extern void enable_sep_cpu(void);
667 extern int sysenter_setup(void);
668 
669 
670 /* Defined in head.S */
671 extern struct desc_ptr		early_gdt_descr;
672 
673 extern void switch_to_new_gdt(int);
674 extern void load_direct_gdt(int);
675 extern void load_fixmap_gdt(int);
676 extern void load_percpu_segment(int);
677 extern void cpu_init(void);
678 extern void cpu_init_secondary(void);
679 extern void cpu_init_exception_handling(void);
680 extern void cr4_init(void);
681 
682 static inline unsigned long get_debugctlmsr(void)
683 {
684 	unsigned long debugctlmsr = 0;
685 
686 #ifndef CONFIG_X86_DEBUGCTLMSR
687 	if (boot_cpu_data.x86 < 6)
688 		return 0;
689 #endif
690 	rdmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
691 
692 	return debugctlmsr;
693 }
694 
695 static inline void update_debugctlmsr(unsigned long debugctlmsr)
696 {
697 #ifndef CONFIG_X86_DEBUGCTLMSR
698 	if (boot_cpu_data.x86 < 6)
699 		return;
700 #endif
701 	wrmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
702 }
703 
704 extern void set_task_blockstep(struct task_struct *task, bool on);
705 
706 /* Boot loader type from the setup header: */
707 extern int			bootloader_type;
708 extern int			bootloader_version;
709 
710 extern char			ignore_fpu_irq;
711 
712 #define HAVE_ARCH_PICK_MMAP_LAYOUT 1
713 #define ARCH_HAS_PREFETCHW
714 #define ARCH_HAS_SPINLOCK_PREFETCH
715 
716 #ifdef CONFIG_X86_32
717 # define BASE_PREFETCH		""
718 # define ARCH_HAS_PREFETCH
719 #else
720 # define BASE_PREFETCH		"prefetcht0 %P1"
721 #endif
722 
723 /*
724  * Prefetch instructions for Pentium III (+) and AMD Athlon (+)
725  *
726  * It's not worth to care about 3dnow prefetches for the K6
727  * because they are microcoded there and very slow.
728  */
729 static inline void prefetch(const void *x)
730 {
731 	alternative_input(BASE_PREFETCH, "prefetchnta %P1",
732 			  X86_FEATURE_XMM,
733 			  "m" (*(const char *)x));
734 }
735 
736 /*
737  * 3dnow prefetch to get an exclusive cache line.
738  * Useful for spinlocks to avoid one state transition in the
739  * cache coherency protocol:
740  */
741 static __always_inline void prefetchw(const void *x)
742 {
743 	alternative_input(BASE_PREFETCH, "prefetchw %P1",
744 			  X86_FEATURE_3DNOWPREFETCH,
745 			  "m" (*(const char *)x));
746 }
747 
748 static inline void spin_lock_prefetch(const void *x)
749 {
750 	prefetchw(x);
751 }
752 
753 #define TOP_OF_INIT_STACK ((unsigned long)&init_stack + sizeof(init_stack) - \
754 			   TOP_OF_KERNEL_STACK_PADDING)
755 
756 #define task_top_of_stack(task) ((unsigned long)(task_pt_regs(task) + 1))
757 
758 #define task_pt_regs(task) \
759 ({									\
760 	unsigned long __ptr = (unsigned long)task_stack_page(task);	\
761 	__ptr += THREAD_SIZE - TOP_OF_KERNEL_STACK_PADDING;		\
762 	((struct pt_regs *)__ptr) - 1;					\
763 })
764 
765 #ifdef CONFIG_X86_32
766 #define INIT_THREAD  {							  \
767 	.sp0			= TOP_OF_INIT_STACK,			  \
768 	.sysenter_cs		= __KERNEL_CS,				  \
769 }
770 
771 #define KSTK_ESP(task)		(task_pt_regs(task)->sp)
772 
773 #else
774 #define INIT_THREAD { }
775 
776 extern unsigned long KSTK_ESP(struct task_struct *task);
777 
778 #endif /* CONFIG_X86_64 */
779 
780 extern void start_thread(struct pt_regs *regs, unsigned long new_ip,
781 					       unsigned long new_sp);
782 
783 /*
784  * This decides where the kernel will search for a free chunk of vm
785  * space during mmap's.
786  */
787 #define __TASK_UNMAPPED_BASE(task_size)	(PAGE_ALIGN(task_size / 3))
788 #define TASK_UNMAPPED_BASE		__TASK_UNMAPPED_BASE(TASK_SIZE_LOW)
789 
790 #define KSTK_EIP(task)		(task_pt_regs(task)->ip)
791 
792 /* Get/set a process' ability to use the timestamp counter instruction */
793 #define GET_TSC_CTL(adr)	get_tsc_mode((adr))
794 #define SET_TSC_CTL(val)	set_tsc_mode((val))
795 
796 extern int get_tsc_mode(unsigned long adr);
797 extern int set_tsc_mode(unsigned int val);
798 
799 DECLARE_PER_CPU(u64, msr_misc_features_shadow);
800 
801 extern u16 get_llc_id(unsigned int cpu);
802 
803 #ifdef CONFIG_CPU_SUP_AMD
804 extern u32 amd_get_nodes_per_socket(void);
805 extern u32 amd_get_highest_perf(void);
806 #else
807 static inline u32 amd_get_nodes_per_socket(void)	{ return 0; }
808 static inline u32 amd_get_highest_perf(void)		{ return 0; }
809 #endif
810 
811 #define for_each_possible_hypervisor_cpuid_base(function) \
812 	for (function = 0x40000000; function < 0x40010000; function += 0x100)
813 
814 static inline uint32_t hypervisor_cpuid_base(const char *sig, uint32_t leaves)
815 {
816 	uint32_t base, eax, signature[3];
817 
818 	for_each_possible_hypervisor_cpuid_base(base) {
819 		cpuid(base, &eax, &signature[0], &signature[1], &signature[2]);
820 
821 		if (!memcmp(sig, signature, 12) &&
822 		    (leaves == 0 || ((eax - base) >= leaves)))
823 			return base;
824 	}
825 
826 	return 0;
827 }
828 
829 extern unsigned long arch_align_stack(unsigned long sp);
830 void free_init_pages(const char *what, unsigned long begin, unsigned long end);
831 extern void free_kernel_image_pages(const char *what, void *begin, void *end);
832 
833 void default_idle(void);
834 #ifdef	CONFIG_XEN
835 bool xen_set_default_idle(void);
836 #else
837 #define xen_set_default_idle 0
838 #endif
839 
840 void __noreturn stop_this_cpu(void *dummy);
841 void microcode_check(void);
842 
843 enum l1tf_mitigations {
844 	L1TF_MITIGATION_OFF,
845 	L1TF_MITIGATION_FLUSH_NOWARN,
846 	L1TF_MITIGATION_FLUSH,
847 	L1TF_MITIGATION_FLUSH_NOSMT,
848 	L1TF_MITIGATION_FULL,
849 	L1TF_MITIGATION_FULL_FORCE
850 };
851 
852 extern enum l1tf_mitigations l1tf_mitigation;
853 
854 enum mds_mitigations {
855 	MDS_MITIGATION_OFF,
856 	MDS_MITIGATION_FULL,
857 	MDS_MITIGATION_VMWERV,
858 };
859 
860 #ifdef CONFIG_X86_SGX
861 int arch_memory_failure(unsigned long pfn, int flags);
862 #define arch_memory_failure arch_memory_failure
863 
864 bool arch_is_platform_page(u64 paddr);
865 #define arch_is_platform_page arch_is_platform_page
866 #endif
867 
868 #endif /* _ASM_X86_PROCESSOR_H */
869