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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 	/* cpuid returned max cores value: */
123 	u16			x86_max_cores;
124 	u16			apicid;
125 	u16			initial_apicid;
126 	u16			x86_clflush_size;
127 	/* number of cores as seen by the OS: */
128 	u16			booted_cores;
129 	/* Physical processor id: */
130 	u16			phys_proc_id;
131 	/* Logical processor id: */
132 	u16			logical_proc_id;
133 	/* Core id: */
134 	u16			cpu_core_id;
135 	u16			cpu_die_id;
136 	u16			logical_die_id;
137 	/* Index into per_cpu list: */
138 	u16			cpu_index;
139 	u32			microcode;
140 	/* Address space bits used by the cache internally */
141 	u8			x86_cache_bits;
142 	unsigned		initialized : 1;
143 } __randomize_layout;
144 
145 struct cpuid_regs {
146 	u32 eax, ebx, ecx, edx;
147 };
148 
149 enum cpuid_regs_idx {
150 	CPUID_EAX = 0,
151 	CPUID_EBX,
152 	CPUID_ECX,
153 	CPUID_EDX,
154 };
155 
156 #define X86_VENDOR_INTEL	0
157 #define X86_VENDOR_CYRIX	1
158 #define X86_VENDOR_AMD		2
159 #define X86_VENDOR_UMC		3
160 #define X86_VENDOR_CENTAUR	5
161 #define X86_VENDOR_TRANSMETA	7
162 #define X86_VENDOR_NSC		8
163 #define X86_VENDOR_HYGON	9
164 #define X86_VENDOR_ZHAOXIN	10
165 #define X86_VENDOR_NUM		11
166 
167 #define X86_VENDOR_UNKNOWN	0xff
168 
169 /*
170  * capabilities of CPUs
171  */
172 extern struct cpuinfo_x86	boot_cpu_data;
173 extern struct cpuinfo_x86	new_cpu_data;
174 
175 extern __u32			cpu_caps_cleared[NCAPINTS + NBUGINTS];
176 extern __u32			cpu_caps_set[NCAPINTS + NBUGINTS];
177 
178 #ifdef CONFIG_SMP
179 DECLARE_PER_CPU_READ_MOSTLY(struct cpuinfo_x86, cpu_info);
180 #define cpu_data(cpu)		per_cpu(cpu_info, cpu)
181 #else
182 #define cpu_info		boot_cpu_data
183 #define cpu_data(cpu)		boot_cpu_data
184 #endif
185 
186 extern const struct seq_operations cpuinfo_op;
187 
188 #define cache_line_size()	(boot_cpu_data.x86_cache_alignment)
189 
190 extern void cpu_detect(struct cpuinfo_x86 *c);
191 
l1tf_pfn_limit(void)192 static inline unsigned long long l1tf_pfn_limit(void)
193 {
194 	return BIT_ULL(boot_cpu_data.x86_cache_bits - 1 - PAGE_SHIFT);
195 }
196 
197 extern void early_cpu_init(void);
198 extern void identify_boot_cpu(void);
199 extern void identify_secondary_cpu(struct cpuinfo_x86 *);
200 extern void print_cpu_info(struct cpuinfo_x86 *);
201 void print_cpu_msr(struct cpuinfo_x86 *);
202 
203 #ifdef CONFIG_X86_32
204 extern int have_cpuid_p(void);
205 #else
have_cpuid_p(void)206 static inline int have_cpuid_p(void)
207 {
208 	return 1;
209 }
210 #endif
native_cpuid(unsigned int * eax,unsigned int * ebx,unsigned int * ecx,unsigned int * edx)211 static inline void native_cpuid(unsigned int *eax, unsigned int *ebx,
212 				unsigned int *ecx, unsigned int *edx)
213 {
214 	/* ecx is often an input as well as an output. */
215 	asm volatile("cpuid"
216 	    : "=a" (*eax),
217 	      "=b" (*ebx),
218 	      "=c" (*ecx),
219 	      "=d" (*edx)
220 	    : "0" (*eax), "2" (*ecx)
221 	    : "memory");
222 }
223 
224 #define native_cpuid_reg(reg)					\
225 static inline unsigned int native_cpuid_##reg(unsigned int op)	\
226 {								\
227 	unsigned int eax = op, ebx, ecx = 0, edx;		\
228 								\
229 	native_cpuid(&eax, &ebx, &ecx, &edx);			\
230 								\
231 	return reg;						\
232 }
233 
234 /*
235  * Native CPUID functions returning a single datum.
236  */
237 native_cpuid_reg(eax)
native_cpuid_reg(ebx)238 native_cpuid_reg(ebx)
239 native_cpuid_reg(ecx)
240 native_cpuid_reg(edx)
241 
242 /*
243  * Friendlier CR3 helpers.
244  */
245 static inline unsigned long read_cr3_pa(void)
246 {
247 	return __read_cr3() & CR3_ADDR_MASK;
248 }
249 
native_read_cr3_pa(void)250 static inline unsigned long native_read_cr3_pa(void)
251 {
252 	return __native_read_cr3() & CR3_ADDR_MASK;
253 }
254 
load_cr3(pgd_t * pgdir)255 static inline void load_cr3(pgd_t *pgdir)
256 {
257 	write_cr3(__sme_pa(pgdir));
258 }
259 
260 /*
261  * Note that while the legacy 'TSS' name comes from 'Task State Segment',
262  * on modern x86 CPUs the TSS also holds information important to 64-bit mode,
263  * unrelated to the task-switch mechanism:
264  */
265 #ifdef CONFIG_X86_32
266 /* This is the TSS defined by the hardware. */
267 struct x86_hw_tss {
268 	unsigned short		back_link, __blh;
269 	unsigned long		sp0;
270 	unsigned short		ss0, __ss0h;
271 	unsigned long		sp1;
272 
273 	/*
274 	 * We don't use ring 1, so ss1 is a convenient scratch space in
275 	 * the same cacheline as sp0.  We use ss1 to cache the value in
276 	 * MSR_IA32_SYSENTER_CS.  When we context switch
277 	 * MSR_IA32_SYSENTER_CS, we first check if the new value being
278 	 * written matches ss1, and, if it's not, then we wrmsr the new
279 	 * value and update ss1.
280 	 *
281 	 * The only reason we context switch MSR_IA32_SYSENTER_CS is
282 	 * that we set it to zero in vm86 tasks to avoid corrupting the
283 	 * stack if we were to go through the sysenter path from vm86
284 	 * mode.
285 	 */
286 	unsigned short		ss1;	/* MSR_IA32_SYSENTER_CS */
287 
288 	unsigned short		__ss1h;
289 	unsigned long		sp2;
290 	unsigned short		ss2, __ss2h;
291 	unsigned long		__cr3;
292 	unsigned long		ip;
293 	unsigned long		flags;
294 	unsigned long		ax;
295 	unsigned long		cx;
296 	unsigned long		dx;
297 	unsigned long		bx;
298 	unsigned long		sp;
299 	unsigned long		bp;
300 	unsigned long		si;
301 	unsigned long		di;
302 	unsigned short		es, __esh;
303 	unsigned short		cs, __csh;
304 	unsigned short		ss, __ssh;
305 	unsigned short		ds, __dsh;
306 	unsigned short		fs, __fsh;
307 	unsigned short		gs, __gsh;
308 	unsigned short		ldt, __ldth;
309 	unsigned short		trace;
310 	unsigned short		io_bitmap_base;
311 
312 } __attribute__((packed));
313 #else
314 struct x86_hw_tss {
315 	u32			reserved1;
316 	u64			sp0;
317 
318 	/*
319 	 * We store cpu_current_top_of_stack in sp1 so it's always accessible.
320 	 * Linux does not use ring 1, so sp1 is not otherwise needed.
321 	 */
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(struct irq_stack *, hardirq_stack_ptr);
430 
431 #ifdef CONFIG_X86_32
432 DECLARE_PER_CPU(unsigned long, cpu_current_top_of_stack);
433 #else
434 /* The RO copy can't be accessed with this_cpu_xyz(), so use the RW copy. */
435 #define cpu_current_top_of_stack cpu_tss_rw.x86_tss.sp1
436 #endif
437 
438 #ifdef CONFIG_X86_64
439 struct fixed_percpu_data {
440 	/*
441 	 * GCC hardcodes the stack canary as %gs:40.  Since the
442 	 * irq_stack is the object at %gs:0, we reserve the bottom
443 	 * 48 bytes of the irq stack for the canary.
444 	 */
445 	char		gs_base[40];
446 	unsigned long	stack_canary;
447 };
448 
449 DECLARE_PER_CPU_FIRST(struct fixed_percpu_data, fixed_percpu_data) __visible;
450 DECLARE_INIT_PER_CPU(fixed_percpu_data);
451 
cpu_kernelmode_gs_base(int cpu)452 static inline unsigned long cpu_kernelmode_gs_base(int cpu)
453 {
454 	return (unsigned long)per_cpu(fixed_percpu_data.gs_base, cpu);
455 }
456 
457 DECLARE_PER_CPU(unsigned int, irq_count);
458 extern asmlinkage void ignore_sysret(void);
459 
460 /* Save actual FS/GS selectors and bases to current->thread */
461 void current_save_fsgs(void);
462 #else	/* X86_64 */
463 #ifdef CONFIG_STACKPROTECTOR
464 /*
465  * Make sure stack canary segment base is cached-aligned:
466  *   "For Intel Atom processors, avoid non zero segment base address
467  *    that is not aligned to cache line boundary at all cost."
468  * (Optim Ref Manual Assembly/Compiler Coding Rule 15.)
469  */
470 struct stack_canary {
471 	char __pad[20];		/* canary at %gs:20 */
472 	unsigned long canary;
473 };
474 DECLARE_PER_CPU_ALIGNED(struct stack_canary, stack_canary);
475 #endif
476 /* Per CPU softirq stack pointer */
477 DECLARE_PER_CPU(struct irq_stack *, softirq_stack_ptr);
478 #endif	/* X86_64 */
479 
480 extern unsigned int fpu_kernel_xstate_size;
481 extern unsigned int fpu_user_xstate_size;
482 
483 struct perf_event;
484 
485 struct thread_struct {
486 	/* Cached TLS descriptors: */
487 	struct desc_struct	tls_array[GDT_ENTRY_TLS_ENTRIES];
488 #ifdef CONFIG_X86_32
489 	unsigned long		sp0;
490 #endif
491 	unsigned long		sp;
492 #ifdef CONFIG_X86_32
493 	unsigned long		sysenter_cs;
494 #else
495 	unsigned short		es;
496 	unsigned short		ds;
497 	unsigned short		fsindex;
498 	unsigned short		gsindex;
499 #endif
500 
501 #ifdef CONFIG_X86_64
502 	unsigned long		fsbase;
503 	unsigned long		gsbase;
504 #else
505 	/*
506 	 * XXX: this could presumably be unsigned short.  Alternatively,
507 	 * 32-bit kernels could be taught to use fsindex instead.
508 	 */
509 	unsigned long fs;
510 	unsigned long gs;
511 #endif
512 
513 	/* Save middle states of ptrace breakpoints */
514 	struct perf_event	*ptrace_bps[HBP_NUM];
515 	/* Debug status used for traps, single steps, etc... */
516 	unsigned long           virtual_dr6;
517 	/* Keep track of the exact dr7 value set by the user */
518 	unsigned long           ptrace_dr7;
519 	/* Fault info: */
520 	unsigned long		cr2;
521 	unsigned long		trap_nr;
522 	unsigned long		error_code;
523 #ifdef CONFIG_VM86
524 	/* Virtual 86 mode info */
525 	struct vm86		*vm86;
526 #endif
527 	/* IO permissions: */
528 	struct io_bitmap	*io_bitmap;
529 
530 	/*
531 	 * IOPL. Priviledge level dependent I/O permission which is
532 	 * emulated via the I/O bitmap to prevent user space from disabling
533 	 * interrupts.
534 	 */
535 	unsigned long		iopl_emul;
536 
537 	unsigned int		iopl_warn:1;
538 	unsigned int		sig_on_uaccess_err:1;
539 
540 	/* Floating point and extended processor state */
541 	struct fpu		fpu;
542 	/*
543 	 * WARNING: 'fpu' is dynamically-sized.  It *MUST* be at
544 	 * the end.
545 	 */
546 };
547 
548 /* Whitelist the FPU state from the task_struct for hardened usercopy. */
arch_thread_struct_whitelist(unsigned long * offset,unsigned long * size)549 static inline void arch_thread_struct_whitelist(unsigned long *offset,
550 						unsigned long *size)
551 {
552 	*offset = offsetof(struct thread_struct, fpu.state);
553 	*size = fpu_kernel_xstate_size;
554 }
555 
556 static inline void
native_load_sp0(unsigned long sp0)557 native_load_sp0(unsigned long sp0)
558 {
559 	this_cpu_write(cpu_tss_rw.x86_tss.sp0, sp0);
560 }
561 
native_swapgs(void)562 static __always_inline void native_swapgs(void)
563 {
564 #ifdef CONFIG_X86_64
565 	asm volatile("swapgs" ::: "memory");
566 #endif
567 }
568 
current_top_of_stack(void)569 static inline unsigned long current_top_of_stack(void)
570 {
571 	/*
572 	 *  We can't read directly from tss.sp0: sp0 on x86_32 is special in
573 	 *  and around vm86 mode and sp0 on x86_64 is special because of the
574 	 *  entry trampoline.
575 	 */
576 	return this_cpu_read_stable(cpu_current_top_of_stack);
577 }
578 
on_thread_stack(void)579 static inline bool on_thread_stack(void)
580 {
581 	return (unsigned long)(current_top_of_stack() -
582 			       current_stack_pointer) < THREAD_SIZE;
583 }
584 
585 #ifdef CONFIG_PARAVIRT_XXL
586 #include <asm/paravirt.h>
587 #else
588 #define __cpuid			native_cpuid
589 
load_sp0(unsigned long sp0)590 static inline void load_sp0(unsigned long sp0)
591 {
592 	native_load_sp0(sp0);
593 }
594 
595 #endif /* CONFIG_PARAVIRT_XXL */
596 
597 /* Free all resources held by a thread. */
598 extern void release_thread(struct task_struct *);
599 
600 unsigned long get_wchan(struct task_struct *p);
601 
602 /*
603  * Generic CPUID function
604  * clear %ecx since some cpus (Cyrix MII) do not set or clear %ecx
605  * resulting in stale register contents being returned.
606  */
cpuid(unsigned int op,unsigned int * eax,unsigned int * ebx,unsigned int * ecx,unsigned int * edx)607 static inline void cpuid(unsigned int op,
608 			 unsigned int *eax, unsigned int *ebx,
609 			 unsigned int *ecx, unsigned int *edx)
610 {
611 	*eax = op;
612 	*ecx = 0;
613 	__cpuid(eax, ebx, ecx, edx);
614 }
615 
616 /* Some CPUID calls want 'count' to be placed in ecx */
cpuid_count(unsigned int op,int count,unsigned int * eax,unsigned int * ebx,unsigned int * ecx,unsigned int * edx)617 static inline void cpuid_count(unsigned int op, int count,
618 			       unsigned int *eax, unsigned int *ebx,
619 			       unsigned int *ecx, unsigned int *edx)
620 {
621 	*eax = op;
622 	*ecx = count;
623 	__cpuid(eax, ebx, ecx, edx);
624 }
625 
626 /*
627  * CPUID functions returning a single datum
628  */
cpuid_eax(unsigned int op)629 static inline unsigned int cpuid_eax(unsigned int op)
630 {
631 	unsigned int eax, ebx, ecx, edx;
632 
633 	cpuid(op, &eax, &ebx, &ecx, &edx);
634 
635 	return eax;
636 }
637 
cpuid_ebx(unsigned int op)638 static inline unsigned int cpuid_ebx(unsigned int op)
639 {
640 	unsigned int eax, ebx, ecx, edx;
641 
642 	cpuid(op, &eax, &ebx, &ecx, &edx);
643 
644 	return ebx;
645 }
646 
cpuid_ecx(unsigned int op)647 static inline unsigned int cpuid_ecx(unsigned int op)
648 {
649 	unsigned int eax, ebx, ecx, edx;
650 
651 	cpuid(op, &eax, &ebx, &ecx, &edx);
652 
653 	return ecx;
654 }
655 
cpuid_edx(unsigned int op)656 static inline unsigned int cpuid_edx(unsigned int op)
657 {
658 	unsigned int eax, ebx, ecx, edx;
659 
660 	cpuid(op, &eax, &ebx, &ecx, &edx);
661 
662 	return edx;
663 }
664 
665 extern void select_idle_routine(const struct cpuinfo_x86 *c);
666 extern void amd_e400_c1e_apic_setup(void);
667 
668 extern unsigned long		boot_option_idle_override;
669 
670 enum idle_boot_override {IDLE_NO_OVERRIDE=0, IDLE_HALT, IDLE_NOMWAIT,
671 			 IDLE_POLL};
672 
673 extern void enable_sep_cpu(void);
674 extern int sysenter_setup(void);
675 
676 
677 /* Defined in head.S */
678 extern struct desc_ptr		early_gdt_descr;
679 
680 extern void switch_to_new_gdt(int);
681 extern void load_direct_gdt(int);
682 extern void load_fixmap_gdt(int);
683 extern void load_percpu_segment(int);
684 extern void cpu_init(void);
685 extern void cpu_init_secondary(void);
686 extern void cpu_init_exception_handling(void);
687 extern void cr4_init(void);
688 
get_debugctlmsr(void)689 static inline unsigned long get_debugctlmsr(void)
690 {
691 	unsigned long debugctlmsr = 0;
692 
693 #ifndef CONFIG_X86_DEBUGCTLMSR
694 	if (boot_cpu_data.x86 < 6)
695 		return 0;
696 #endif
697 	rdmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
698 
699 	return debugctlmsr;
700 }
701 
update_debugctlmsr(unsigned long debugctlmsr)702 static inline void update_debugctlmsr(unsigned long debugctlmsr)
703 {
704 #ifndef CONFIG_X86_DEBUGCTLMSR
705 	if (boot_cpu_data.x86 < 6)
706 		return;
707 #endif
708 	wrmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
709 }
710 
711 extern void set_task_blockstep(struct task_struct *task, bool on);
712 
713 /* Boot loader type from the setup header: */
714 extern int			bootloader_type;
715 extern int			bootloader_version;
716 
717 extern char			ignore_fpu_irq;
718 
719 #define HAVE_ARCH_PICK_MMAP_LAYOUT 1
720 #define ARCH_HAS_PREFETCHW
721 #define ARCH_HAS_SPINLOCK_PREFETCH
722 
723 #ifdef CONFIG_X86_32
724 # define BASE_PREFETCH		""
725 # define ARCH_HAS_PREFETCH
726 #else
727 # define BASE_PREFETCH		"prefetcht0 %P1"
728 #endif
729 
730 /*
731  * Prefetch instructions for Pentium III (+) and AMD Athlon (+)
732  *
733  * It's not worth to care about 3dnow prefetches for the K6
734  * because they are microcoded there and very slow.
735  */
prefetch(const void * x)736 static inline void prefetch(const void *x)
737 {
738 	alternative_input(BASE_PREFETCH, "prefetchnta %P1",
739 			  X86_FEATURE_XMM,
740 			  "m" (*(const char *)x));
741 }
742 
743 /*
744  * 3dnow prefetch to get an exclusive cache line.
745  * Useful for spinlocks to avoid one state transition in the
746  * cache coherency protocol:
747  */
prefetchw(const void * x)748 static __always_inline void prefetchw(const void *x)
749 {
750 	alternative_input(BASE_PREFETCH, "prefetchw %P1",
751 			  X86_FEATURE_3DNOWPREFETCH,
752 			  "m" (*(const char *)x));
753 }
754 
spin_lock_prefetch(const void * x)755 static inline void spin_lock_prefetch(const void *x)
756 {
757 	prefetchw(x);
758 }
759 
760 #define TOP_OF_INIT_STACK ((unsigned long)&init_stack + sizeof(init_stack) - \
761 			   TOP_OF_KERNEL_STACK_PADDING)
762 
763 #define task_top_of_stack(task) ((unsigned long)(task_pt_regs(task) + 1))
764 
765 #define task_pt_regs(task) \
766 ({									\
767 	unsigned long __ptr = (unsigned long)task_stack_page(task);	\
768 	__ptr += THREAD_SIZE - TOP_OF_KERNEL_STACK_PADDING;		\
769 	((struct pt_regs *)__ptr) - 1;					\
770 })
771 
772 #ifdef CONFIG_X86_32
773 #define INIT_THREAD  {							  \
774 	.sp0			= TOP_OF_INIT_STACK,			  \
775 	.sysenter_cs		= __KERNEL_CS,				  \
776 }
777 
778 #define KSTK_ESP(task)		(task_pt_regs(task)->sp)
779 
780 #else
781 #define INIT_THREAD { }
782 
783 extern unsigned long KSTK_ESP(struct task_struct *task);
784 
785 #endif /* CONFIG_X86_64 */
786 
787 extern void start_thread(struct pt_regs *regs, unsigned long new_ip,
788 					       unsigned long new_sp);
789 
790 /*
791  * This decides where the kernel will search for a free chunk of vm
792  * space during mmap's.
793  */
794 #define __TASK_UNMAPPED_BASE(task_size)	(PAGE_ALIGN(task_size / 3))
795 #define TASK_UNMAPPED_BASE		__TASK_UNMAPPED_BASE(TASK_SIZE_LOW)
796 
797 #define KSTK_EIP(task)		(task_pt_regs(task)->ip)
798 
799 /* Get/set a process' ability to use the timestamp counter instruction */
800 #define GET_TSC_CTL(adr)	get_tsc_mode((adr))
801 #define SET_TSC_CTL(val)	set_tsc_mode((val))
802 
803 extern int get_tsc_mode(unsigned long adr);
804 extern int set_tsc_mode(unsigned int val);
805 
806 DECLARE_PER_CPU(u64, msr_misc_features_shadow);
807 
808 #ifdef CONFIG_CPU_SUP_AMD
809 extern u16 amd_get_nb_id(int cpu);
810 extern u32 amd_get_nodes_per_socket(void);
811 extern bool cpu_has_ibpb_brtype_microcode(void);
812 extern void amd_clear_divider(void);
813 #else
amd_get_nb_id(int cpu)814 static inline u16 amd_get_nb_id(int cpu)		{ return 0; }
amd_get_nodes_per_socket(void)815 static inline u32 amd_get_nodes_per_socket(void)	{ return 0; }
cpu_has_ibpb_brtype_microcode(void)816 static inline bool cpu_has_ibpb_brtype_microcode(void)	{ return false; }
amd_clear_divider(void)817 static inline void amd_clear_divider(void)		{ }
818 #endif
819 
hypervisor_cpuid_base(const char * sig,uint32_t leaves)820 static inline uint32_t hypervisor_cpuid_base(const char *sig, uint32_t leaves)
821 {
822 	uint32_t base, eax, signature[3];
823 
824 	for (base = 0x40000000; base < 0x40010000; base += 0x100) {
825 		cpuid(base, &eax, &signature[0], &signature[1], &signature[2]);
826 
827 		if (!memcmp(sig, signature, 12) &&
828 		    (leaves == 0 || ((eax - base) >= leaves)))
829 			return base;
830 	}
831 
832 	return 0;
833 }
834 
835 extern unsigned long arch_align_stack(unsigned long sp);
836 void free_init_pages(const char *what, unsigned long begin, unsigned long end);
837 extern void free_kernel_image_pages(const char *what, void *begin, void *end);
838 
839 void default_idle(void);
840 #ifdef	CONFIG_XEN
841 bool xen_set_default_idle(void);
842 #else
843 #define xen_set_default_idle 0
844 #endif
845 
846 void __noreturn stop_this_cpu(void *dummy);
847 void microcode_check(struct cpuinfo_x86 *prev_info);
848 void store_cpu_caps(struct cpuinfo_x86 *info);
849 
850 enum l1tf_mitigations {
851 	L1TF_MITIGATION_OFF,
852 	L1TF_MITIGATION_FLUSH_NOWARN,
853 	L1TF_MITIGATION_FLUSH,
854 	L1TF_MITIGATION_FLUSH_NOSMT,
855 	L1TF_MITIGATION_FULL,
856 	L1TF_MITIGATION_FULL_FORCE
857 };
858 
859 extern enum l1tf_mitigations l1tf_mitigation;
860 
861 enum mds_mitigations {
862 	MDS_MITIGATION_OFF,
863 	MDS_MITIGATION_FULL,
864 	MDS_MITIGATION_VMWERV,
865 };
866 
867 extern bool gds_ucode_mitigated(void);
868 
869 #endif /* _ASM_X86_PROCESSOR_H */
870