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Diffstat (limited to 'arch/x86/include/asm/processor.h')
| -rw-r--r-- | arch/x86/include/asm/processor.h | 1004 |
1 files changed, 1004 insertions, 0 deletions
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h new file mode 100644 index 000000000..cc4bb218f --- /dev/null +++ b/arch/x86/include/asm/processor.h @@ -0,0 +1,1004 @@ +/* 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 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 <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 +/* + * Default implementation of macro that returns current + * instruction pointer ("program counter"). + */ +static inline void *current_text_addr(void) +{ + void *pc; + + asm volatile("mov $1f, %0; 1:":"=r" (pc)); + + return pc; +} + +/* + * 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 (1 << INTERNODE_CACHE_SHIFT) +# define ARCH_MIN_MMSTRUCT_ALIGN (1 << INTERNODE_CACHE_SHIFT) +#else +# define ARCH_MIN_TASKALIGN __alignof__(union fpregs_state) +# define ARCH_MIN_MMSTRUCT_ALIGN 0 +#endif + +enum tlb_infos { + ENTRIES, + NR_INFO +}; + +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; +#endif + __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; + __u32 x86_capability[NCAPINTS + NBUGINTS]; + 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: */ + int x86_cache_max_rmid; /* max index */ + int x86_cache_occ_scale; /* scale to bytes */ + 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; + /* Index into per_cpu list: */ + u16 cpu_index; + 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 { + CPUID_EAX = 0, + CPUID_EBX, + CPUID_ECX, + CPUID_EDX, +}; + +#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_TRANSMETA 7 +#define X86_VENDOR_NSC 8 +#define X86_VENDOR_NUM 9 + +#define X86_VENDOR_UNKNOWN 0xff + +/* + * capabilities of CPUs + */ +extern struct cpuinfo_x86 boot_cpu_data; +extern struct cpuinfo_x86 new_cpu_data; + +extern struct x86_hw_tss doublefault_tss; +extern __u32 cpu_caps_cleared[NCAPINTS + NBUGINTS]; +extern __u32 cpu_caps_set[NCAPINTS + NBUGINTS]; + +#ifdef CONFIG_SMP +DECLARE_PER_CPU_READ_MOSTLY(struct cpuinfo_x86, cpu_info); +#define cpu_data(cpu) per_cpu(cpu_info, cpu) +#else +#define cpu_info boot_cpu_data +#define cpu_data(cpu) boot_cpu_data +#endif + +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); +#else +static inline int have_cpuid_p(void) +{ + return 1; +} +#endif +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. + */ +native_cpuid_reg(eax) +native_cpuid_reg(ebx) +native_cpuid_reg(ecx) +native_cpuid_reg(edx) + +/* + * 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) +{ + write_cr3(__sme_pa(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)); +#else +struct x86_hw_tss { + u32 reserved1; + u64 sp0; + + /* + * We store cpu_current_top_of_stack in sp1 so it's always accessible. + * Linux does not use ring 1, so sp1 is not otherwise needed. + */ + u64 sp1; + + u64 sp2; + u64 reserved2; + u64 ist[7]; + u32 reserved3; + u32 reserved4; + u16 reserved5; + u16 io_bitmap_base; + +} __attribute__((packed)); +#endif + +/* + * IO-bitmap sizes: + */ +#define IO_BITMAP_BITS 65536 +#define IO_BITMAP_BYTES (IO_BITMAP_BITS/8) +#define IO_BITMAP_LONGS (IO_BITMAP_BYTES/sizeof(long)) +#define IO_BITMAP_OFFSET (offsetof(struct tss_struct, io_bitmap) - offsetof(struct tss_struct, x86_tss)) +#define INVALID_IO_BITMAP_OFFSET 0x8000 + +struct entry_stack { + char stack[PAGE_SIZE]; +}; + +struct entry_stack_page { + struct entry_stack stack; +} __aligned(PAGE_SIZE); + +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; + + /* + * 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 io_bitmap[IO_BITMAP_LONGS + 1]; +} __aligned(PAGE_SIZE); + +DECLARE_PER_CPU_PAGE_ALIGNED(struct tss_struct, cpu_tss_rw); + +/* + * sizeof(unsigned long) coming from an extra "long" at the end + * of the iobitmap. + * + * -1? seg base+limit should be pointing to the address of the + * last valid byte + */ +#define __KERNEL_TSS_LIMIT \ + (IO_BITMAP_OFFSET + IO_BITMAP_BYTES + sizeof(unsigned long) - 1) + +#ifdef CONFIG_X86_32 +DECLARE_PER_CPU(unsigned long, cpu_current_top_of_stack); +#else +/* The RO copy can't be accessed with this_cpu_xyz(), so use the RW copy. */ +#define cpu_current_top_of_stack cpu_tss_rw.x86_tss.sp1 +#endif + +/* + * Save the original ist values for checking stack pointers during debugging + */ +struct orig_ist { + unsigned long ist[7]; +}; + +#ifdef CONFIG_X86_64 +DECLARE_PER_CPU(struct orig_ist, orig_ist); + +union irq_stack_union { + char irq_stack[IRQ_STACK_SIZE]; + /* + * 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. + */ + struct { + char gs_base[40]; + unsigned long stack_canary; + }; +}; + +DECLARE_PER_CPU_FIRST(union irq_stack_union, irq_stack_union) __visible; +DECLARE_INIT_PER_CPU(irq_stack_union); + +static inline unsigned long cpu_kernelmode_gs_base(int cpu) +{ + return (unsigned long)per_cpu(irq_stack_union.gs_base, cpu); +} + +DECLARE_PER_CPU(char *, irq_stack_ptr); +DECLARE_PER_CPU(unsigned int, irq_count); +extern asmlinkage void ignore_sysret(void); + +#if IS_ENABLED(CONFIG_KVM) +/* Save actual FS/GS selectors and bases to current->thread */ +void save_fsgs_for_kvm(void); +#endif +#else /* X86_64 */ +#ifdef CONFIG_STACKPROTECTOR +/* + * Make sure stack canary segment base is cached-aligned: + * "For Intel Atom processors, avoid non zero segment base address + * that is not aligned to cache line boundary at all cost." + * (Optim Ref Manual Assembly/Compiler Coding Rule 15.) + */ +struct stack_canary { + char __pad[20]; /* canary at %gs:20 */ + unsigned long canary; +}; +DECLARE_PER_CPU_ALIGNED(struct stack_canary, stack_canary); +#endif +/* + * per-CPU IRQ handling stacks + */ +struct irq_stack { + u32 stack[THREAD_SIZE/sizeof(u32)]; +} __aligned(THREAD_SIZE); + +DECLARE_PER_CPU(struct irq_stack *, hardirq_stack); +DECLARE_PER_CPU(struct irq_stack *, softirq_stack); +#endif /* X86_64 */ + +extern unsigned int fpu_kernel_xstate_size; +extern unsigned int fpu_user_xstate_size; + +struct perf_event; + +typedef struct { + unsigned long seg; +} mm_segment_t; + +struct thread_struct { + /* Cached TLS descriptors: */ + struct desc_struct tls_array[GDT_ENTRY_TLS_ENTRIES]; +#ifdef CONFIG_X86_32 + unsigned long sp0; +#endif + unsigned long sp; +#ifdef CONFIG_X86_32 + unsigned long sysenter_cs; +#else + unsigned short es; + unsigned short ds; + unsigned short fsindex; + unsigned short gsindex; +#endif + +#ifdef CONFIG_X86_64 + unsigned long fsbase; + unsigned long gsbase; +#else + /* + * XXX: this could presumably be unsigned short. Alternatively, + * 32-bit kernels could be taught to use fsindex instead. + */ + unsigned long fs; + unsigned long gs; +#endif + + /* Save middle states of ptrace breakpoints */ + struct perf_event *ptrace_bps[HBP_NUM]; + /* Debug status used for traps, single steps, etc... */ + unsigned long debugreg6; + /* 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; +#endif + /* IO permissions: */ + unsigned long *io_bitmap_ptr; + unsigned long iopl; + /* Max allowed port in the bitmap, in bytes: */ + unsigned io_bitmap_max; + + mm_segment_t addr_limit; + + unsigned int sig_on_uaccess_err:1; + unsigned int uaccess_err:1; /* uaccess failed */ + + /* 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; +} + +/* + * Set IOPL bits in EFLAGS from given mask + */ +static inline void native_set_iopl_mask(unsigned mask) +{ +#ifdef CONFIG_X86_32 + unsigned int reg; + + asm volatile ("pushfl;" + "popl %0;" + "andl %1, %0;" + "orl %2, %0;" + "pushl %0;" + "popfl" + : "=&r" (reg) + : "i" (~X86_EFLAGS_IOPL), "r" (mask)); +#endif +} + +static inline void +native_load_sp0(unsigned long sp0) +{ + this_cpu_write(cpu_tss_rw.x86_tss.sp0, sp0); +} + +static inline void native_swapgs(void) +{ +#ifdef CONFIG_X86_64 + asm volatile("swapgs" ::: "memory"); +#endif +} + +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; +} + +#ifdef CONFIG_PARAVIRT +#include <asm/paravirt.h> +#else +#define __cpuid native_cpuid + +static inline void load_sp0(unsigned long sp0) +{ + native_load_sp0(sp0); +} + +#define set_iopl_mask native_set_iopl_mask +#endif /* CONFIG_PARAVIRT */ + +/* 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; +} + +/* REP NOP (PAUSE) is a good thing to insert into busy-wait loops. */ +static __always_inline void rep_nop(void) +{ + asm volatile("rep; nop" ::: "memory"); +} + +static __always_inline void cpu_relax(void) +{ + rep_nop(); +} + +/* + * This function forces the icache and prefetched instruction stream to + * catch up with reality in two very specific cases: + * + * a) Text was modified using one virtual address and is about to be executed + * from the same physical page at a different virtual address. + * + * b) Text was modified on a different CPU, may subsequently be + * executed on this CPU, and you want to make sure the new version + * gets executed. This generally means you're calling this in a IPI. + * + * If you're calling this for a different reason, you're probably doing + * it wrong. + */ +static inline void sync_core(void) +{ + /* + * There are quite a few ways to do this. IRET-to-self is nice + * because it works on every CPU, at any CPL (so it's compatible + * with paravirtualization), and it never exits to a hypervisor. + * The only down sides are that it's a bit slow (it seems to be + * a bit more than 2x slower than the fastest options) and that + * it unmasks NMIs. The "push %cs" is needed because, in + * paravirtual environments, __KERNEL_CS may not be a valid CS + * value when we do IRET directly. + * + * In case NMI unmasking or performance ever becomes a problem, + * the next best option appears to be MOV-to-CR2 and an + * unconditional jump. That sequence also works on all CPUs, + * but it will fault at CPL3 (i.e. Xen PV). + * + * CPUID is the conventional way, but it's nasty: it doesn't + * exist on some 486-like CPUs, and it usually exits to a + * hypervisor. + * + * Like all of Linux's memory ordering operations, this is a + * compiler barrier as well. + */ +#ifdef CONFIG_X86_32 + asm volatile ( + "pushfl\n\t" + "pushl %%cs\n\t" + "pushl $1f\n\t" + "iret\n\t" + "1:" + : ASM_CALL_CONSTRAINT : : "memory"); +#else + unsigned int tmp; + + asm volatile ( + UNWIND_HINT_SAVE + "mov %%ss, %0\n\t" + "pushq %q0\n\t" + "pushq %%rsp\n\t" + "addq $8, (%%rsp)\n\t" + "pushfq\n\t" + "mov %%cs, %0\n\t" + "pushq %q0\n\t" + "pushq $1f\n\t" + "iretq\n\t" + UNWIND_HINT_RESTORE + "1:" + : "=&r" (tmp), ASM_CALL_CONSTRAINT : : "cc", "memory"); +#endif +} + +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, + IDLE_POLL}; + +extern void enable_sep_cpu(void); +extern int sysenter_setup(void); + +void early_trap_pf_init(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); + +static inline unsigned long get_debugctlmsr(void) +{ + unsigned long debugctlmsr = 0; + +#ifndef CONFIG_X86_DEBUGCTLMSR + if (boot_cpu_data.x86 < 6) + return 0; +#endif + rdmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr); + + return debugctlmsr; +} + +static inline void update_debugctlmsr(unsigned long debugctlmsr) +{ +#ifndef CONFIG_X86_DEBUGCTLMSR + if (boot_cpu_data.x86 < 6) + return; +#endif + 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; + +#define HAVE_ARCH_PICK_MMAP_LAYOUT 1 +#define ARCH_HAS_PREFETCHW +#define ARCH_HAS_SPINLOCK_PREFETCH + +#ifdef CONFIG_X86_32 +# define BASE_PREFETCH "" +# define ARCH_HAS_PREFETCH +#else +# define BASE_PREFETCH "prefetcht0 %P1" +#endif + +/* + * 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", + X86_FEATURE_XMM, + "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 inline void prefetchw(const void *x) +{ + alternative_input(BASE_PREFETCH, "prefetchw %P1", + X86_FEATURE_3DNOWPREFETCH, + "m" (*(const char *)x)); +} + +static inline void spin_lock_prefetch(const void *x) +{ + prefetchw(x); +} + +#define TOP_OF_INIT_STACK ((unsigned long)&init_stack + sizeof(init_stack) - \ + TOP_OF_KERNEL_STACK_PADDING) + +#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); \ + __ptr += THREAD_SIZE - TOP_OF_KERNEL_STACK_PADDING; \ + ((struct pt_regs *)__ptr) - 1; \ +}) + +#ifdef CONFIG_X86_32 +/* + * User space process size: 3GB (default). + */ +#define IA32_PAGE_OFFSET PAGE_OFFSET +#define TASK_SIZE PAGE_OFFSET +#define TASK_SIZE_LOW TASK_SIZE +#define TASK_SIZE_MAX TASK_SIZE +#define DEFAULT_MAP_WINDOW TASK_SIZE +#define STACK_TOP TASK_SIZE +#define STACK_TOP_MAX STACK_TOP + +#define INIT_THREAD { \ + .sp0 = TOP_OF_INIT_STACK, \ + .sysenter_cs = __KERNEL_CS, \ + .io_bitmap_ptr = NULL, \ + .addr_limit = KERNEL_DS, \ +} + +#define KSTK_ESP(task) (task_pt_regs(task)->sp) + +#else +/* + * User space process size. This is the first address outside the user range. + * There are a few constraints that determine this: + * + * On Intel CPUs, if a SYSCALL instruction is at the highest canonical + * address, then that syscall will enter the kernel with a + * non-canonical return address, and SYSRET will explode dangerously. + * We avoid this particular problem by preventing anything executable + * from being mapped at the maximum canonical address. + * + * On AMD CPUs in the Ryzen family, there's a nasty bug in which the + * CPUs malfunction if they execute code from the highest canonical page. + * They'll speculate right off the end of the canonical space, and + * bad things happen. This is worked around in the same way as the + * Intel problem. + * + * With page table isolation enabled, we map the LDT in ... [stay tuned] + */ +#define TASK_SIZE_MAX ((1UL << __VIRTUAL_MASK_SHIFT) - PAGE_SIZE) + +#define DEFAULT_MAP_WINDOW ((1UL << 47) - PAGE_SIZE) + +/* This decides where the kernel will search for a free chunk of vm + * space during mmap's. + */ +#define IA32_PAGE_OFFSET ((current->personality & ADDR_LIMIT_3GB) ? \ + 0xc0000000 : 0xFFFFe000) + +#define TASK_SIZE_LOW (test_thread_flag(TIF_ADDR32) ? \ + IA32_PAGE_OFFSET : DEFAULT_MAP_WINDOW) +#define TASK_SIZE (test_thread_flag(TIF_ADDR32) ? \ + IA32_PAGE_OFFSET : TASK_SIZE_MAX) +#define TASK_SIZE_OF(child) ((test_tsk_thread_flag(child, TIF_ADDR32)) ? \ + IA32_PAGE_OFFSET : TASK_SIZE_MAX) + +#define STACK_TOP TASK_SIZE_LOW +#define STACK_TOP_MAX TASK_SIZE_MAX + +#define INIT_THREAD { \ + .addr_limit = KERNEL_DS, \ +} + +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 TASK_UNMAPPED_BASE __TASK_UNMAPPED_BASE(TASK_SIZE_LOW) + +#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); + +/* Register/unregister a process' MPX related resource */ +#define MPX_ENABLE_MANAGEMENT() mpx_enable_management() +#define MPX_DISABLE_MANAGEMENT() mpx_disable_management() + +#ifdef CONFIG_X86_INTEL_MPX +extern int mpx_enable_management(void); +extern int mpx_disable_management(void); +#else +static inline int mpx_enable_management(void) +{ + return -EINVAL; +} +static inline int mpx_disable_management(void) +{ + return -EINVAL; +} +#endif /* CONFIG_X86_INTEL_MPX */ + +#ifdef CONFIG_CPU_SUP_AMD +extern u16 amd_get_nb_id(int cpu); +extern u32 amd_get_nodes_per_socket(void); +#else +static inline u16 amd_get_nb_id(int cpu) { return 0; } +static inline u32 amd_get_nodes_per_socket(void) { return 0; } +#endif + +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); +extern void free_init_pages(char *what, unsigned long begin, unsigned long end); +extern void free_kernel_image_pages(void *begin, void *end); + +void default_idle(void); +#ifdef CONFIG_XEN +bool xen_set_default_idle(void); +#else +#define xen_set_default_idle 0 +#endif + +void stop_this_cpu(void *dummy); +void df_debug(struct pt_regs *regs, long error_code); +void microcode_check(void); + +enum l1tf_mitigations { + L1TF_MITIGATION_OFF, + L1TF_MITIGATION_FLUSH_NOWARN, + L1TF_MITIGATION_FLUSH, + L1TF_MITIGATION_FLUSH_NOSMT, + L1TF_MITIGATION_FULL, + L1TF_MITIGATION_FULL_FORCE +}; + +extern enum l1tf_mitigations l1tf_mitigation; + +enum mds_mitigations { + MDS_MITIGATION_OFF, + MDS_MITIGATION_FULL, + MDS_MITIGATION_VMWERV, +}; + +enum taa_mitigations { + TAA_MITIGATION_OFF, + TAA_MITIGATION_UCODE_NEEDED, + TAA_MITIGATION_VERW, + TAA_MITIGATION_TSX_DISABLED, +}; + +#endif /* _ASM_X86_PROCESSOR_H */ |