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Diffstat (limited to 'arch/arm64/include/asm/processor.h')
-rw-r--r-- | arch/arm64/include/asm/processor.h | 331 |
1 files changed, 331 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h new file mode 100644 index 000000000..c628d8e3a --- /dev/null +++ b/arch/arm64/include/asm/processor.h @@ -0,0 +1,331 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Based on arch/arm/include/asm/processor.h + * + * Copyright (C) 1995-1999 Russell King + * Copyright (C) 2012 ARM Ltd. + */ +#ifndef __ASM_PROCESSOR_H +#define __ASM_PROCESSOR_H + +#define KERNEL_DS UL(-1) +#define USER_DS ((UL(1) << VA_BITS) - 1) + +/* + * On arm64 systems, unaligned accesses by the CPU are cheap, and so there is + * no point in shifting all network buffers by 2 bytes just to make some IP + * header fields appear aligned in memory, potentially sacrificing some DMA + * performance on some platforms. + */ +#define NET_IP_ALIGN 0 + +#ifndef __ASSEMBLY__ + +#include <linux/build_bug.h> +#include <linux/cache.h> +#include <linux/init.h> +#include <linux/stddef.h> +#include <linux/string.h> +#include <linux/thread_info.h> + +#include <vdso/processor.h> + +#include <asm/alternative.h> +#include <asm/cpufeature.h> +#include <asm/hw_breakpoint.h> +#include <asm/kasan.h> +#include <asm/lse.h> +#include <asm/pgtable-hwdef.h> +#include <asm/pointer_auth.h> +#include <asm/ptrace.h> +#include <asm/spectre.h> +#include <asm/types.h> + +/* + * TASK_SIZE - the maximum size of a user space task. + * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area. + */ + +#define DEFAULT_MAP_WINDOW_64 (UL(1) << VA_BITS_MIN) +#define TASK_SIZE_64 (UL(1) << vabits_actual) + +#ifdef CONFIG_COMPAT +#if defined(CONFIG_ARM64_64K_PAGES) && defined(CONFIG_KUSER_HELPERS) +/* + * With CONFIG_ARM64_64K_PAGES enabled, the last page is occupied + * by the compat vectors page. + */ +#define TASK_SIZE_32 UL(0x100000000) +#else +#define TASK_SIZE_32 (UL(0x100000000) - PAGE_SIZE) +#endif /* CONFIG_ARM64_64K_PAGES */ +#define TASK_SIZE (test_thread_flag(TIF_32BIT) ? \ + TASK_SIZE_32 : TASK_SIZE_64) +#define TASK_SIZE_OF(tsk) (test_tsk_thread_flag(tsk, TIF_32BIT) ? \ + TASK_SIZE_32 : TASK_SIZE_64) +#define DEFAULT_MAP_WINDOW (test_thread_flag(TIF_32BIT) ? \ + TASK_SIZE_32 : DEFAULT_MAP_WINDOW_64) +#else +#define TASK_SIZE TASK_SIZE_64 +#define DEFAULT_MAP_WINDOW DEFAULT_MAP_WINDOW_64 +#endif /* CONFIG_COMPAT */ + +#ifdef CONFIG_ARM64_FORCE_52BIT +#define STACK_TOP_MAX TASK_SIZE_64 +#define TASK_UNMAPPED_BASE (PAGE_ALIGN(TASK_SIZE / 4)) +#else +#define STACK_TOP_MAX DEFAULT_MAP_WINDOW_64 +#define TASK_UNMAPPED_BASE (PAGE_ALIGN(DEFAULT_MAP_WINDOW / 4)) +#endif /* CONFIG_ARM64_FORCE_52BIT */ + +#ifdef CONFIG_COMPAT +#define AARCH32_VECTORS_BASE 0xffff0000 +#define STACK_TOP (test_thread_flag(TIF_32BIT) ? \ + AARCH32_VECTORS_BASE : STACK_TOP_MAX) +#else +#define STACK_TOP STACK_TOP_MAX +#endif /* CONFIG_COMPAT */ + +#ifndef CONFIG_ARM64_FORCE_52BIT +#define arch_get_mmap_end(addr) ((addr > DEFAULT_MAP_WINDOW) ? TASK_SIZE :\ + DEFAULT_MAP_WINDOW) + +#define arch_get_mmap_base(addr, base) ((addr > DEFAULT_MAP_WINDOW) ? \ + base + TASK_SIZE - DEFAULT_MAP_WINDOW :\ + base) +#endif /* CONFIG_ARM64_FORCE_52BIT */ + +extern phys_addr_t arm64_dma_phys_limit; +#define ARCH_LOW_ADDRESS_LIMIT (arm64_dma_phys_limit - 1) + +struct debug_info { +#ifdef CONFIG_HAVE_HW_BREAKPOINT + /* Have we suspended stepping by a debugger? */ + int suspended_step; + /* Allow breakpoints and watchpoints to be disabled for this thread. */ + int bps_disabled; + int wps_disabled; + /* Hardware breakpoints pinned to this task. */ + struct perf_event *hbp_break[ARM_MAX_BRP]; + struct perf_event *hbp_watch[ARM_MAX_WRP]; +#endif +}; + +struct cpu_context { + unsigned long x19; + unsigned long x20; + unsigned long x21; + unsigned long x22; + unsigned long x23; + unsigned long x24; + unsigned long x25; + unsigned long x26; + unsigned long x27; + unsigned long x28; + unsigned long fp; + unsigned long sp; + unsigned long pc; +}; + +struct thread_struct { + struct cpu_context cpu_context; /* cpu context */ + + /* + * Whitelisted fields for hardened usercopy: + * Maintainers must ensure manually that this contains no + * implicit padding. + */ + struct { + unsigned long tp_value; /* TLS register */ + unsigned long tp2_value; + struct user_fpsimd_state fpsimd_state; + } uw; + + unsigned int fpsimd_cpu; + void *sve_state; /* SVE registers, if any */ + unsigned int sve_vl; /* SVE vector length */ + unsigned int sve_vl_onexec; /* SVE vl after next exec */ + unsigned long fault_address; /* fault info */ + unsigned long fault_code; /* ESR_EL1 value */ + struct debug_info debug; /* debugging */ +#ifdef CONFIG_ARM64_PTR_AUTH + struct ptrauth_keys_user keys_user; + struct ptrauth_keys_kernel keys_kernel; +#endif +#ifdef CONFIG_ARM64_MTE + u64 sctlr_tcf0; + u64 gcr_user_incl; +#endif +}; + +static inline void arch_thread_struct_whitelist(unsigned long *offset, + unsigned long *size) +{ + /* Verify that there is no padding among the whitelisted fields: */ + BUILD_BUG_ON(sizeof_field(struct thread_struct, uw) != + sizeof_field(struct thread_struct, uw.tp_value) + + sizeof_field(struct thread_struct, uw.tp2_value) + + sizeof_field(struct thread_struct, uw.fpsimd_state)); + + *offset = offsetof(struct thread_struct, uw); + *size = sizeof_field(struct thread_struct, uw); +} + +#ifdef CONFIG_COMPAT +#define task_user_tls(t) \ +({ \ + unsigned long *__tls; \ + if (is_compat_thread(task_thread_info(t))) \ + __tls = &(t)->thread.uw.tp2_value; \ + else \ + __tls = &(t)->thread.uw.tp_value; \ + __tls; \ + }) +#else +#define task_user_tls(t) (&(t)->thread.uw.tp_value) +#endif + +/* Sync TPIDR_EL0 back to thread_struct for current */ +void tls_preserve_current_state(void); + +#define INIT_THREAD { \ + .fpsimd_cpu = NR_CPUS, \ +} + +static inline void start_thread_common(struct pt_regs *regs, unsigned long pc) +{ + s32 previous_syscall = regs->syscallno; + memset(regs, 0, sizeof(*regs)); + regs->syscallno = previous_syscall; + regs->pc = pc; + + if (system_uses_irq_prio_masking()) + regs->pmr_save = GIC_PRIO_IRQON; +} + +static inline void start_thread(struct pt_regs *regs, unsigned long pc, + unsigned long sp) +{ + start_thread_common(regs, pc); + regs->pstate = PSR_MODE_EL0t; + spectre_v4_enable_task_mitigation(current); + regs->sp = sp; +} + +#ifdef CONFIG_COMPAT +static inline void compat_start_thread(struct pt_regs *regs, unsigned long pc, + unsigned long sp) +{ + start_thread_common(regs, pc); + regs->pstate = PSR_AA32_MODE_USR; + if (pc & 1) + regs->pstate |= PSR_AA32_T_BIT; + +#ifdef __AARCH64EB__ + regs->pstate |= PSR_AA32_E_BIT; +#endif + + spectre_v4_enable_task_mitigation(current); + regs->compat_sp = sp; +} +#endif + +static __always_inline bool is_ttbr0_addr(unsigned long addr) +{ + /* entry assembly clears tags for TTBR0 addrs */ + return addr < TASK_SIZE; +} + +static __always_inline bool is_ttbr1_addr(unsigned long addr) +{ + /* TTBR1 addresses may have a tag if KASAN_SW_TAGS is in use */ + return arch_kasan_reset_tag(addr) >= PAGE_OFFSET; +} + +/* Forward declaration, a strange C thing */ +struct task_struct; + +/* Free all resources held by a thread. */ +extern void release_thread(struct task_struct *); + +unsigned long get_wchan(struct task_struct *p); + +/* Thread switching */ +extern struct task_struct *cpu_switch_to(struct task_struct *prev, + struct task_struct *next); + +#define task_pt_regs(p) \ + ((struct pt_regs *)(THREAD_SIZE + task_stack_page(p)) - 1) + +#define KSTK_EIP(tsk) ((unsigned long)task_pt_regs(tsk)->pc) +#define KSTK_ESP(tsk) user_stack_pointer(task_pt_regs(tsk)) + +/* + * Prefetching support + */ +#define ARCH_HAS_PREFETCH +static inline void prefetch(const void *ptr) +{ + asm volatile("prfm pldl1keep, %a0\n" : : "p" (ptr)); +} + +#define ARCH_HAS_PREFETCHW +static inline void prefetchw(const void *ptr) +{ + asm volatile("prfm pstl1keep, %a0\n" : : "p" (ptr)); +} + +#define ARCH_HAS_SPINLOCK_PREFETCH +static inline void spin_lock_prefetch(const void *ptr) +{ + asm volatile(ARM64_LSE_ATOMIC_INSN( + "prfm pstl1strm, %a0", + "nop") : : "p" (ptr)); +} + +extern unsigned long __ro_after_init signal_minsigstksz; /* sigframe size */ +extern void __init minsigstksz_setup(void); + +/* + * Not at the top of the file due to a direct #include cycle between + * <asm/fpsimd.h> and <asm/processor.h>. Deferring this #include + * ensures that contents of processor.h are visible to fpsimd.h even if + * processor.h is included first. + * + * These prctl helpers are the only things in this file that require + * fpsimd.h. The core code expects them to be in this header. + */ +#include <asm/fpsimd.h> + +/* Userspace interface for PR_SVE_{SET,GET}_VL prctl()s: */ +#define SVE_SET_VL(arg) sve_set_current_vl(arg) +#define SVE_GET_VL() sve_get_current_vl() + +/* PR_PAC_RESET_KEYS prctl */ +#define PAC_RESET_KEYS(tsk, arg) ptrauth_prctl_reset_keys(tsk, arg) + +#ifdef CONFIG_ARM64_TAGGED_ADDR_ABI +/* PR_{SET,GET}_TAGGED_ADDR_CTRL prctl */ +long set_tagged_addr_ctrl(struct task_struct *task, unsigned long arg); +long get_tagged_addr_ctrl(struct task_struct *task); +#define SET_TAGGED_ADDR_CTRL(arg) set_tagged_addr_ctrl(current, arg) +#define GET_TAGGED_ADDR_CTRL() get_tagged_addr_ctrl(current) +#endif + +/* + * For CONFIG_GCC_PLUGIN_STACKLEAK + * + * These need to be macros because otherwise we get stuck in a nightmare + * of header definitions for the use of task_stack_page. + */ + +#define current_top_of_stack() \ +({ \ + struct stack_info _info; \ + BUG_ON(!on_accessible_stack(current, current_stack_pointer, &_info)); \ + _info.high; \ +}) +#define on_thread_stack() (on_task_stack(current, current_stack_pointer, NULL)) + +#endif /* __ASSEMBLY__ */ +#endif /* __ASM_PROCESSOR_H */ |