blob: 9ad2acaaae9b84be5bece5730bfb8e7c746cc892 [file] [log] [blame]
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_PROCESSOR_H
#define _ASM_X86_PROCESSOR_H
#include <asm/processor-flags.h>
/* Forward declaration, a strange C thing */
struct task_struct;
struct mm_struct;
struct io_bitmap;
struct vm86;
#include <asm/math_emu.h>
#include <asm/segment.h>
#include <asm/types.h>
#include <uapi/asm/sigcontext.h>
#include <asm/current.h>
#include <asm/cpufeatures.h>
#include <asm/page.h>
#include <asm/pgtable_types.h>
#include <asm/percpu.h>
#include <asm/msr.h>
#include <asm/desc_defs.h>
#include <asm/nops.h>
#include <asm/special_insns.h>
#include <asm/fpu/types.h>
#include <asm/unwind_hints.h>
#include <asm/vmxfeatures.h>
#include <asm/vdso/processor.h>
#include <linux/personality.h>
#include <linux/cache.h>
#include <linux/threads.h>
#include <linux/math64.h>
#include <linux/err.h>
#include <linux/irqflags.h>
#include <linux/mem_encrypt.h>
* We handle most unaligned accesses in hardware. On the other hand
* unaligned DMA can be quite expensive on some Nehalem processors.
* Based on this we disable the IP header alignment in network drivers.
#define NET_IP_ALIGN 0
#define HBP_NUM 4
* These alignment constraints are for performance in the vSMP case,
* but in the task_struct case we must also meet hardware imposed
* alignment requirements of the FPU state:
#ifdef CONFIG_X86_VSMP
# define ARCH_MIN_TASKALIGN __alignof__(union fpregs_state)
enum tlb_infos {
extern u16 __read_mostly tlb_lli_4k[NR_INFO];
extern u16 __read_mostly tlb_lli_2m[NR_INFO];
extern u16 __read_mostly tlb_lli_4m[NR_INFO];
extern u16 __read_mostly tlb_lld_4k[NR_INFO];
extern u16 __read_mostly tlb_lld_2m[NR_INFO];
extern u16 __read_mostly tlb_lld_4m[NR_INFO];
extern u16 __read_mostly tlb_lld_1g[NR_INFO];
* CPU type and hardware bug flags. Kept separately for each CPU.
* Members of this structure are referenced in head_32.S, so think twice
* before touching them. [mj]
struct cpuinfo_x86 {
__u8 x86; /* CPU family */
__u8 x86_vendor; /* CPU vendor */
__u8 x86_model;
__u8 x86_stepping;
#ifdef CONFIG_X86_64
/* Number of 4K pages in DTLB/ITLB combined(in pages): */
int x86_tlbsize;
__u32 vmx_capability[NVMXINTS];
__u8 x86_virt_bits;
__u8 x86_phys_bits;
/* CPUID returned core id bits: */
__u8 x86_coreid_bits;
__u8 cu_id;
/* Max extended CPUID function supported: */
__u32 extended_cpuid_level;
/* Maximum supported CPUID level, -1=no CPUID: */
int cpuid_level;
* Align to size of unsigned long because the x86_capability array
* is passed to bitops which require the alignment. Use unnamed
* union to enforce the array is aligned to size of unsigned long.
union {
__u32 x86_capability[NCAPINTS + NBUGINTS];
unsigned long x86_capability_alignment;
char x86_vendor_id[16];
char x86_model_id[64];
/* in KB - valid for CPUS which support this call: */
unsigned int x86_cache_size;
int x86_cache_alignment; /* In bytes */
/* Cache QoS architectural values, valid only on the BSP: */
int x86_cache_max_rmid; /* max index */
int x86_cache_occ_scale; /* scale to bytes */
int x86_cache_mbm_width_offset;
int x86_power;
unsigned long loops_per_jiffy;
/* cpuid returned max cores value: */
u16 x86_max_cores;
u16 apicid;
u16 initial_apicid;
u16 x86_clflush_size;
/* number of cores as seen by the OS: */
u16 booted_cores;
/* Physical processor id: */
u16 phys_proc_id;
/* Logical processor id: */
u16 logical_proc_id;
/* Core id: */
u16 cpu_core_id;
u16 cpu_die_id;
u16 logical_die_id;
/* Index into per_cpu list: */
u16 cpu_index;
/* Is SMT active on this core? */
bool smt_active;
u32 microcode;
/* Address space bits used by the cache internally */
u8 x86_cache_bits;
unsigned initialized : 1;
} __randomize_layout;
struct cpuid_regs {
u32 eax, ebx, ecx, edx;
enum cpuid_regs_idx {
#define X86_VENDOR_INTEL 0
#define X86_VENDOR_CYRIX 1
#define X86_VENDOR_AMD 2
#define X86_VENDOR_UMC 3
#define X86_VENDOR_CENTAUR 5
#define X86_VENDOR_NSC 8
#define X86_VENDOR_HYGON 9
#define X86_VENDOR_ZHAOXIN 10
#define X86_VENDOR_NUM 11
#define X86_VENDOR_UNKNOWN 0xff
* capabilities of CPUs
extern struct cpuinfo_x86 boot_cpu_data;
extern struct cpuinfo_x86 new_cpu_data;
extern __u32 cpu_caps_cleared[NCAPINTS + NBUGINTS];
extern __u32 cpu_caps_set[NCAPINTS + NBUGINTS];
DECLARE_PER_CPU_READ_MOSTLY(struct cpuinfo_x86, cpu_info);
#define cpu_data(cpu) per_cpu(cpu_info, cpu)
#define cpu_info boot_cpu_data
#define cpu_data(cpu) boot_cpu_data
extern const struct seq_operations cpuinfo_op;
#define cache_line_size() (boot_cpu_data.x86_cache_alignment)
extern void cpu_detect(struct cpuinfo_x86 *c);
static inline unsigned long long l1tf_pfn_limit(void)
return BIT_ULL(boot_cpu_data.x86_cache_bits - 1 - PAGE_SHIFT);
extern void early_cpu_init(void);
extern void identify_boot_cpu(void);
extern void identify_secondary_cpu(struct cpuinfo_x86 *);
extern void print_cpu_info(struct cpuinfo_x86 *);
void print_cpu_msr(struct cpuinfo_x86 *);
#ifdef CONFIG_X86_32
extern int have_cpuid_p(void);
static inline int have_cpuid_p(void)
return 1;
static inline void native_cpuid(unsigned int *eax, unsigned int *ebx,
unsigned int *ecx, unsigned int *edx)
/* ecx is often an input as well as an output. */
asm volatile("cpuid"
: "=a" (*eax),
"=b" (*ebx),
"=c" (*ecx),
"=d" (*edx)
: "0" (*eax), "2" (*ecx)
: "memory");
#define native_cpuid_reg(reg) \
static inline unsigned int native_cpuid_##reg(unsigned int op) \
{ \
unsigned int eax = op, ebx, ecx = 0, edx; \
native_cpuid(&eax, &ebx, &ecx, &edx); \
return reg; \
* Native CPUID functions returning a single datum.
* Friendlier CR3 helpers.
static inline unsigned long read_cr3_pa(void)
return __read_cr3() & CR3_ADDR_MASK;
static inline unsigned long native_read_cr3_pa(void)
return __native_read_cr3() & CR3_ADDR_MASK;
static inline void load_cr3(pgd_t *pgdir)
* Note that while the legacy 'TSS' name comes from 'Task State Segment',
* on modern x86 CPUs the TSS also holds information important to 64-bit mode,
* unrelated to the task-switch mechanism:
#ifdef CONFIG_X86_32
/* This is the TSS defined by the hardware. */
struct x86_hw_tss {
unsigned short back_link, __blh;
unsigned long sp0;
unsigned short ss0, __ss0h;
unsigned long sp1;
* We don't use ring 1, so ss1 is a convenient scratch space in
* the same cacheline as sp0. We use ss1 to cache the value in
* MSR_IA32_SYSENTER_CS. When we context switch
* MSR_IA32_SYSENTER_CS, we first check if the new value being
* written matches ss1, and, if it's not, then we wrmsr the new
* value and update ss1.
* The only reason we context switch MSR_IA32_SYSENTER_CS is
* that we set it to zero in vm86 tasks to avoid corrupting the
* stack if we were to go through the sysenter path from vm86
* mode.
unsigned short ss1; /* MSR_IA32_SYSENTER_CS */
unsigned short __ss1h;
unsigned long sp2;
unsigned short ss2, __ss2h;
unsigned long __cr3;
unsigned long ip;
unsigned long flags;
unsigned long ax;
unsigned long cx;
unsigned long dx;
unsigned long bx;
unsigned long sp;
unsigned long bp;
unsigned long si;
unsigned long di;
unsigned short es, __esh;
unsigned short cs, __csh;
unsigned short ss, __ssh;
unsigned short ds, __dsh;
unsigned short fs, __fsh;
unsigned short gs, __gsh;
unsigned short ldt, __ldth;
unsigned short trace;
unsigned short io_bitmap_base;
} __attribute__((packed));
struct x86_hw_tss {
u32 reserved1;
u64 sp0;
u64 sp1;
* Since Linux does not use ring 2, the 'sp2' slot is unused by
* hardware. entry_SYSCALL_64 uses it as scratch space to stash
* the user RSP value.
u64 sp2;
u64 reserved2;
u64 ist[7];
u32 reserved3;
u32 reserved4;
u16 reserved5;
u16 io_bitmap_base;
} __attribute__((packed));
* IO-bitmap sizes:
#define IO_BITMAP_BITS 65536
#define IO_BITMAP_LONGS (IO_BITMAP_BYTES / sizeof(long))
(offsetof(struct tss_struct, io_bitmap.bitmap) - \
offsetof(struct tss_struct, x86_tss))
(offsetof(struct tss_struct, io_bitmap.mapall) - \
offsetof(struct tss_struct, x86_tss))
* sizeof(unsigned long) coming from an extra "long" at the end of the
* iobitmap. The limit is inclusive, i.e. the last valid byte.
# define __KERNEL_TSS_LIMIT \
sizeof(unsigned long) - 1)
# define __KERNEL_TSS_LIMIT \
(offsetof(struct tss_struct, x86_tss) + sizeof(struct x86_hw_tss) - 1)
/* Base offset outside of TSS_LIMIT so unpriviledged IO causes #GP */
struct entry_stack {
char stack[PAGE_SIZE];
struct entry_stack_page {
struct entry_stack stack;
} __aligned(PAGE_SIZE);
* All IO bitmap related data stored in the TSS:
struct x86_io_bitmap {
/* The sequence number of the last active bitmap. */
u64 prev_sequence;
* Store the dirty size of the last io bitmap offender. The next
* one will have to do the cleanup as the switch out to a non io
* bitmap user will just set x86_tss.io_bitmap_base to a value
* outside of the TSS limit. So for sane tasks there is no need to
* actually touch the io_bitmap at all.
unsigned int prev_max;
* The extra 1 is there because the CPU will access an
* additional byte beyond the end of the IO permission
* bitmap. The extra byte must be all 1 bits, and must
* be within the limit.
unsigned long bitmap[IO_BITMAP_LONGS + 1];
* Special I/O bitmap to emulate IOPL(3). All bytes zero,
* except the additional byte at the end.
unsigned long mapall[IO_BITMAP_LONGS + 1];
struct tss_struct {
* The fixed hardware portion. This must not cross a page boundary
* at risk of violating the SDM's advice and potentially triggering
* errata.
struct x86_hw_tss x86_tss;
struct x86_io_bitmap io_bitmap;
} __aligned(PAGE_SIZE);
DECLARE_PER_CPU_PAGE_ALIGNED(struct tss_struct, cpu_tss_rw);
/* Per CPU interrupt stacks */
struct irq_stack {
char stack[IRQ_STACK_SIZE];
} __aligned(IRQ_STACK_SIZE);
DECLARE_PER_CPU(unsigned long, cpu_current_top_of_stack);
#ifdef CONFIG_X86_64
struct fixed_percpu_data {
* GCC hardcodes the stack canary as %gs:40. Since the
* irq_stack is the object at %gs:0, we reserve the bottom
* 48 bytes of the irq stack for the canary.
* Once we are willing to require -mstack-protector-guard-symbol=
* support for x86_64 stackprotector, we can get rid of this.
char gs_base[40];
unsigned long stack_canary;
DECLARE_PER_CPU_FIRST(struct fixed_percpu_data, fixed_percpu_data) __visible;
static inline unsigned long cpu_kernelmode_gs_base(int cpu)
return (unsigned long)per_cpu(fixed_percpu_data.gs_base, cpu);
DECLARE_PER_CPU(void *, hardirq_stack_ptr);
DECLARE_PER_CPU(bool, hardirq_stack_inuse);
extern asmlinkage void ignore_sysret(void);
/* Save actual FS/GS selectors and bases to current->thread */
void current_save_fsgs(void);
#else /* X86_64 */
DECLARE_PER_CPU(unsigned long, __stack_chk_guard);
DECLARE_PER_CPU(struct irq_stack *, hardirq_stack_ptr);
DECLARE_PER_CPU(struct irq_stack *, softirq_stack_ptr);
#endif /* !X86_64 */
extern unsigned int fpu_kernel_xstate_size;
extern unsigned int fpu_user_xstate_size;
struct perf_event;
struct thread_struct {
/* Cached TLS descriptors: */
struct desc_struct tls_array[GDT_ENTRY_TLS_ENTRIES];
#ifdef CONFIG_X86_32
unsigned long sp0;
unsigned long sp;
#ifdef CONFIG_X86_32
unsigned long sysenter_cs;
unsigned short es;
unsigned short ds;
unsigned short fsindex;
unsigned short gsindex;
#ifdef CONFIG_X86_64
unsigned long fsbase;
unsigned long gsbase;
* XXX: this could presumably be unsigned short. Alternatively,
* 32-bit kernels could be taught to use fsindex instead.
unsigned long fs;
unsigned long gs;
/* Save middle states of ptrace breakpoints */
struct perf_event *ptrace_bps[HBP_NUM];
/* Debug status used for traps, single steps, etc... */
unsigned long virtual_dr6;
/* Keep track of the exact dr7 value set by the user */
unsigned long ptrace_dr7;
/* Fault info: */
unsigned long cr2;
unsigned long trap_nr;
unsigned long error_code;
#ifdef CONFIG_VM86
/* Virtual 86 mode info */
struct vm86 *vm86;
/* IO permissions: */
struct io_bitmap *io_bitmap;
* IOPL. Privilege level dependent I/O permission which is
* emulated via the I/O bitmap to prevent user space from disabling
* interrupts.
unsigned long iopl_emul;
unsigned int sig_on_uaccess_err:1;
* Protection Keys Register for Userspace. Loaded immediately on
* context switch. Store it in thread_struct to avoid a lookup in
* the tasks's FPU xstate buffer. This value is only valid when a
* task is scheduled out. For 'current' the authoritative source of
* PKRU is the hardware itself.
u32 pkru;
/* Floating point and extended processor state */
struct fpu fpu;
* WARNING: 'fpu' is dynamically-sized. It *MUST* be at
* the end.
/* Whitelist the FPU state from the task_struct for hardened usercopy. */
static inline void arch_thread_struct_whitelist(unsigned long *offset,
unsigned long *size)
*offset = offsetof(struct thread_struct, fpu.state);
*size = fpu_kernel_xstate_size;
static inline void
native_load_sp0(unsigned long sp0)
this_cpu_write(cpu_tss_rw.x86_tss.sp0, sp0);
static __always_inline void native_swapgs(void)
#ifdef CONFIG_X86_64
asm volatile("swapgs" ::: "memory");
static inline unsigned long current_top_of_stack(void)
* We can't read directly from tss.sp0: sp0 on x86_32 is special in
* and around vm86 mode and sp0 on x86_64 is special because of the
* entry trampoline.
return this_cpu_read_stable(cpu_current_top_of_stack);
static inline bool on_thread_stack(void)
return (unsigned long)(current_top_of_stack() -
current_stack_pointer) < THREAD_SIZE;
#include <asm/paravirt.h>
#define __cpuid native_cpuid
static inline void load_sp0(unsigned long sp0)
/* Free all resources held by a thread. */
extern void release_thread(struct task_struct *);
unsigned long get_wchan(struct task_struct *p);
* Generic CPUID function
* clear %ecx since some cpus (Cyrix MII) do not set or clear %ecx
* resulting in stale register contents being returned.
static inline void cpuid(unsigned int op,
unsigned int *eax, unsigned int *ebx,
unsigned int *ecx, unsigned int *edx)
*eax = op;
*ecx = 0;
__cpuid(eax, ebx, ecx, edx);
/* Some CPUID calls want 'count' to be placed in ecx */
static inline void cpuid_count(unsigned int op, int count,
unsigned int *eax, unsigned int *ebx,
unsigned int *ecx, unsigned int *edx)
*eax = op;
*ecx = count;
__cpuid(eax, ebx, ecx, edx);
* CPUID functions returning a single datum
static inline unsigned int cpuid_eax(unsigned int op)
unsigned int eax, ebx, ecx, edx;
cpuid(op, &eax, &ebx, &ecx, &edx);
return eax;
static inline unsigned int cpuid_ebx(unsigned int op)
unsigned int eax, ebx, ecx, edx;
cpuid(op, &eax, &ebx, &ecx, &edx);
return ebx;
static inline unsigned int cpuid_ecx(unsigned int op)
unsigned int eax, ebx, ecx, edx;
cpuid(op, &eax, &ebx, &ecx, &edx);
return ecx;
static inline unsigned int cpuid_edx(unsigned int op)
unsigned int eax, ebx, ecx, edx;
cpuid(op, &eax, &ebx, &ecx, &edx);
return edx;
extern void select_idle_routine(const struct cpuinfo_x86 *c);
extern void amd_e400_c1e_apic_setup(void);
extern unsigned long boot_option_idle_override;
enum idle_boot_override {IDLE_NO_OVERRIDE=0, IDLE_HALT, IDLE_NOMWAIT,
extern void enable_sep_cpu(void);
extern int sysenter_setup(void);
/* Defined in head.S */
extern struct desc_ptr early_gdt_descr;
extern void switch_to_new_gdt(int);
extern void load_direct_gdt(int);
extern void load_fixmap_gdt(int);
extern void load_percpu_segment(int);
extern void cpu_init(void);
extern void cpu_init_secondary(void);
extern void cpu_init_exception_handling(void);
extern void cr4_init(void);
static inline unsigned long get_debugctlmsr(void)
unsigned long debugctlmsr = 0;
if (boot_cpu_data.x86 < 6)
return 0;
rdmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
return debugctlmsr;
static inline void update_debugctlmsr(unsigned long debugctlmsr)
if (boot_cpu_data.x86 < 6)
wrmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
extern void set_task_blockstep(struct task_struct *task, bool on);
/* Boot loader type from the setup header: */
extern int bootloader_type;
extern int bootloader_version;
extern char ignore_fpu_irq;
#ifdef CONFIG_X86_32
# define BASE_PREFETCH ""
# define BASE_PREFETCH "prefetcht0 %P1"
* Prefetch instructions for Pentium III (+) and AMD Athlon (+)
* It's not worth to care about 3dnow prefetches for the K6
* because they are microcoded there and very slow.
static inline void prefetch(const void *x)
alternative_input(BASE_PREFETCH, "prefetchnta %P1",
"m" (*(const char *)x));
* 3dnow prefetch to get an exclusive cache line.
* Useful for spinlocks to avoid one state transition in the
* cache coherency protocol:
static __always_inline void prefetchw(const void *x)
alternative_input(BASE_PREFETCH, "prefetchw %P1",
"m" (*(const char *)x));
static inline void spin_lock_prefetch(const void *x)
#define TOP_OF_INIT_STACK ((unsigned long)&init_stack + sizeof(init_stack) - \
#define task_top_of_stack(task) ((unsigned long)(task_pt_regs(task) + 1))
#define task_pt_regs(task) \
({ \
unsigned long __ptr = (unsigned long)task_stack_page(task); \
((struct pt_regs *)__ptr) - 1; \
#ifdef CONFIG_X86_32
#define INIT_THREAD { \
.sysenter_cs = __KERNEL_CS, \
#define KSTK_ESP(task) (task_pt_regs(task)->sp)
#define INIT_THREAD { }
extern unsigned long KSTK_ESP(struct task_struct *task);
#endif /* CONFIG_X86_64 */
extern void start_thread(struct pt_regs *regs, unsigned long new_ip,
unsigned long new_sp);
* This decides where the kernel will search for a free chunk of vm
* space during mmap's.
#define __TASK_UNMAPPED_BASE(task_size) (PAGE_ALIGN(task_size / 3))
#define KSTK_EIP(task) (task_pt_regs(task)->ip)
/* Get/set a process' ability to use the timestamp counter instruction */
#define GET_TSC_CTL(adr) get_tsc_mode((adr))
#define SET_TSC_CTL(val) set_tsc_mode((val))
extern int get_tsc_mode(unsigned long adr);
extern int set_tsc_mode(unsigned int val);
DECLARE_PER_CPU(u64, msr_misc_features_shadow);
extern u16 get_llc_id(unsigned int cpu);
extern u32 amd_get_nodes_per_socket(void);
extern u32 amd_get_highest_perf(void);
static inline u32 amd_get_nodes_per_socket(void) { return 0; }
static inline u32 amd_get_highest_perf(void) { return 0; }
static inline uint32_t hypervisor_cpuid_base(const char *sig, uint32_t leaves)
uint32_t base, eax, signature[3];
for (base = 0x40000000; base < 0x40010000; base += 0x100) {
cpuid(base, &eax, &signature[0], &signature[1], &signature[2]);
if (!memcmp(sig, signature, 12) &&
(leaves == 0 || ((eax - base) >= leaves)))
return base;
return 0;
extern unsigned long arch_align_stack(unsigned long sp);
void free_init_pages(const char *what, unsigned long begin, unsigned long end);
extern void free_kernel_image_pages(const char *what, void *begin, void *end);
void default_idle(void);
bool xen_set_default_idle(void);
#define xen_set_default_idle 0
void stop_this_cpu(void *dummy);
void microcode_check(void);
enum l1tf_mitigations {
extern enum l1tf_mitigations l1tf_mitigation;
enum mds_mitigations {
#endif /* _ASM_X86_PROCESSOR_H */