/* SPDX-License-Identifier: GPL-2.0 */ #ifndef _ASM_X86_PROCESSOR_H #define _ASM_X86_PROCESSOR_H #include /* Forward declaration, a strange C thing */ struct task_struct; struct mm_struct; struct io_bitmap; struct vm86; #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * 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 (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. */ struct cpuinfo_topology { // Real APIC ID read from the local APIC u32 apicid; // The initial APIC ID provided by CPUID u32 initial_apicid; // Physical package ID u32 pkg_id; // Physical die ID on AMD, Relative on Intel u32 die_id; // Compute unit ID - AMD specific u32 cu_id; // Core ID relative to the package u32 core_id; // Logical ID mappings u32 logical_pkg_id; u32 logical_die_id; // AMD Node ID and Nodes per Package info u32 amd_node_id; // Cache level topology IDs u32 llc_id; u32 l2c_id; }; struct cpuinfo_x86 { union { /* * The particular ordering (low-to-high) of (vendor, * family, model) is done in case range of models, like * it is usually done on AMD, need to be compared. */ struct { __u8 x86_model; /* CPU family */ __u8 x86; /* CPU vendor */ __u8 x86_vendor; __u8 x86_reserved; }; /* combined vendor, family, model */ __u32 x86_vfm; }; __u8 x86_stepping; #ifdef CONFIG_X86_64 /* Number of 4K pages in DTLB/ITLB combined(in pages): */ int x86_tlbsize; #endif #ifdef CONFIG_X86_VMX_FEATURE_NAMES __u32 vmx_capability[NVMXINTS]; #endif __u8 x86_virt_bits; __u8 x86_phys_bits; /* 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]; struct cpuinfo_topology topo; /* 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; /* protected processor identification number */ u64 ppin; u16 x86_clflush_size; /* number of cores as seen by the OS: */ u16 booted_cores; /* 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; #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_HYGON 9 #define X86_VENDOR_ZHAOXIN 10 #define X86_VENDOR_VORTEX 11 #define X86_VENDOR_NUM 12 #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) 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_secondary_cpu(struct cpuinfo_x86 *); extern void print_cpu_info(struct cpuinfo_x86 *); void print_cpu_msr(struct cpuinfo_x86 *); /* * 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; 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)); #endif /* * IO-bitmap sizes: */ #define IO_BITMAP_BITS 65536 #define IO_BITMAP_BYTES (IO_BITMAP_BITS / BITS_PER_BYTE) #define IO_BITMAP_LONGS (IO_BITMAP_BYTES / sizeof(long)) #define IO_BITMAP_OFFSET_VALID_MAP \ (offsetof(struct tss_struct, io_bitmap.bitmap) - \ offsetof(struct tss_struct, x86_tss)) #define IO_BITMAP_OFFSET_VALID_ALL \ (offsetof(struct tss_struct, io_bitmap.mapall) - \ offsetof(struct tss_struct, x86_tss)) #ifdef CONFIG_X86_IOPL_IOPERM /* * 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 \ (IO_BITMAP_OFFSET_VALID_ALL + IO_BITMAP_BYTES + \ sizeof(unsigned long) - 1) #else # define __KERNEL_TSS_LIMIT \ (offsetof(struct tss_struct, x86_tss) + sizeof(struct x86_hw_tss) - 1) #endif /* Base offset outside of TSS_LIMIT so unpriviledged IO causes #GP */ #define IO_BITMAP_OFFSET_INVALID (__KERNEL_TSS_LIMIT + 1) 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); #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; DECLARE_INIT_PER_CPU(fixed_percpu_data); static inline unsigned long cpu_kernelmode_gs_base(int cpu) { return (unsigned long)per_cpu(fixed_percpu_data.gs_base, cpu); } extern asmlinkage void entry_SYSCALL32_ignore(void); /* Save actual FS/GS selectors and bases to current->thread */ void current_save_fsgs(void); #else /* X86_64 */ #ifdef CONFIG_STACKPROTECTOR DECLARE_PER_CPU(unsigned long, __stack_chk_guard); #endif #endif /* !X86_64 */ 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; #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 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; #endif /* 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 iopl_warn: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; #ifdef CONFIG_X86_USER_SHADOW_STACK unsigned long features; unsigned long features_locked; struct thread_shstk shstk; #endif /* Floating point and extended processor state */ struct fpu fpu; /* * WARNING: 'fpu' is dynamically-sized. It *MUST* be at * the end. */ }; extern void fpu_thread_struct_whitelist(unsigned long *offset, unsigned long *size); static inline void arch_thread_struct_whitelist(unsigned long *offset, unsigned long *size) { fpu_thread_struct_whitelist(offset, 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"); #endif } static __always_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. */ if (IS_ENABLED(CONFIG_USE_X86_SEG_SUPPORT)) return this_cpu_read_const(const_pcpu_hot.top_of_stack); return this_cpu_read_stable(pcpu_hot.top_of_stack); } static __always_inline bool on_thread_stack(void) { return (unsigned long)(current_top_of_stack() - current_stack_pointer) < THREAD_SIZE; } #ifdef CONFIG_PARAVIRT_XXL #include #else static inline void load_sp0(unsigned long sp0) { native_load_sp0(sp0); } #endif /* CONFIG_PARAVIRT_XXL */ unsigned long __get_wchan(struct task_struct *p); extern void select_idle_routine(void); 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); /* Defined in head.S */ extern struct desc_ptr early_gdt_descr; extern void switch_gdt_and_percpu_base(int); extern void load_direct_gdt(int); extern void load_fixmap_gdt(int); extern void cpu_init(void); extern void cpu_init_exception_handling(bool boot_cpu); extern void cpu_init_replace_early_idt(void); extern void cr4_init(void); 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 #ifdef CONFIG_X86_32 # define BASE_PREFETCH "" # define ARCH_HAS_PREFETCH #else # define BASE_PREFETCH "prefetcht0 %1" #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 %1", 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 __always_inline void prefetchw(const void *x) { alternative_input(BASE_PREFETCH, "prefetchw %1", X86_FEATURE_3DNOWPREFETCH, "m" (*(const char *)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 #define INIT_THREAD { \ .sp0 = TOP_OF_INIT_STACK, \ .sysenter_cs = __KERNEL_CS, \ } #define KSTK_ESP(task) (task_pt_regs(task)->sp) #else extern unsigned long __top_init_kernel_stack[]; #define INIT_THREAD { \ .sp = (unsigned long)&__top_init_kernel_stack, \ } 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); static inline u32 per_cpu_llc_id(unsigned int cpu) { return per_cpu(cpu_info.topo.llc_id, cpu); } static inline u32 per_cpu_l2c_id(unsigned int cpu) { return per_cpu(cpu_info.topo.l2c_id, cpu); } #ifdef CONFIG_CPU_SUP_AMD /* * Issue a DIV 0/1 insn to clear any division data from previous DIV * operations. */ static __always_inline void amd_clear_divider(void) { asm volatile(ALTERNATIVE("", "div %2\n\t", X86_BUG_DIV0) :: "a" (0), "d" (0), "r" (1)); } extern void amd_check_microcode(void); #else static inline void amd_clear_divider(void) { } static inline void amd_check_microcode(void) { } #endif 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); #ifdef CONFIG_XEN bool xen_set_default_idle(void); #else #define xen_set_default_idle 0 #endif void __noreturn stop_this_cpu(void *dummy); void microcode_check(struct cpuinfo_x86 *prev_info); void store_cpu_caps(struct cpuinfo_x86 *info); 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, }; extern bool gds_ucode_mitigated(void); /* * Make previous memory operations globally visible before * a WRMSR. * * MFENCE makes writes visible, but only affects load/store * instructions. WRMSR is unfortunately not a load/store * instruction and is unaffected by MFENCE. The LFENCE ensures * that the WRMSR is not reordered. * * Most WRMSRs are full serializing instructions themselves and * do not require this barrier. This is only required for the * IA32_TSC_DEADLINE and X2APIC MSRs. */ static inline void weak_wrmsr_fence(void) { alternative("mfence; lfence", "", ALT_NOT(X86_FEATURE_APIC_MSRS_FENCE)); } #endif /* _ASM_X86_PROCESSOR_H */