cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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thread_info.h (6753B)


      1/* SPDX-License-Identifier: GPL-2.0 */
      2/* thread_info.h: MIPS low-level thread information
      3 *
      4 * Copyright (C) 2002  David Howells (dhowells@redhat.com)
      5 * - Incorporating suggestions made by Linus Torvalds and Dave Miller
      6 */
      7
      8#ifndef _ASM_THREAD_INFO_H
      9#define _ASM_THREAD_INFO_H
     10
     11#ifdef __KERNEL__
     12
     13
     14#ifndef __ASSEMBLY__
     15
     16#include <asm/processor.h>
     17
     18/*
     19 * low level task data that entry.S needs immediate access to
     20 * - this struct should fit entirely inside of one cache line
     21 * - this struct shares the supervisor stack pages
     22 * - if the contents of this structure are changed, the assembly constants
     23 *   must also be changed
     24 */
     25struct thread_info {
     26	struct task_struct	*task;		/* main task structure */
     27	unsigned long		flags;		/* low level flags */
     28	unsigned long		tp_value;	/* thread pointer */
     29	__u32			cpu;		/* current CPU */
     30	int			preempt_count;	/* 0 => preemptable, <0 => BUG */
     31	struct pt_regs		*regs;
     32	long			syscall;	/* syscall number */
     33};
     34
     35/*
     36 * macros/functions for gaining access to the thread information structure
     37 */
     38#define INIT_THREAD_INFO(tsk)			\
     39{						\
     40	.task		= &tsk,			\
     41	.flags		= _TIF_FIXADE,		\
     42	.cpu		= 0,			\
     43	.preempt_count	= INIT_PREEMPT_COUNT,	\
     44}
     45
     46/*
     47 * A pointer to the struct thread_info for the currently executing thread is
     48 * held in register $28/$gp.
     49 *
     50 * We declare __current_thread_info as a global register variable rather than a
     51 * local register variable within current_thread_info() because clang doesn't
     52 * support explicit local register variables.
     53 *
     54 * When building the VDSO we take care not to declare the global register
     55 * variable because this causes GCC to not preserve the value of $28/$gp in
     56 * functions that change its value (which is common in the PIC VDSO when
     57 * accessing the GOT). Since the VDSO shouldn't be accessing
     58 * __current_thread_info anyway we declare it extern in order to cause a link
     59 * failure if it's referenced.
     60 */
     61#ifdef __VDSO__
     62extern struct thread_info *__current_thread_info;
     63#else
     64register struct thread_info *__current_thread_info __asm__("$28");
     65#endif
     66
     67static inline struct thread_info *current_thread_info(void)
     68{
     69	return __current_thread_info;
     70}
     71
     72#ifdef CONFIG_ARCH_HAS_CURRENT_STACK_POINTER
     73register unsigned long current_stack_pointer __asm__("sp");
     74#endif
     75
     76#endif /* !__ASSEMBLY__ */
     77
     78/* thread information allocation */
     79#if defined(CONFIG_PAGE_SIZE_4KB) && defined(CONFIG_32BIT)
     80#define THREAD_SIZE_ORDER (1)
     81#endif
     82#if defined(CONFIG_PAGE_SIZE_4KB) && defined(CONFIG_64BIT)
     83#define THREAD_SIZE_ORDER (2)
     84#endif
     85#ifdef CONFIG_PAGE_SIZE_8KB
     86#define THREAD_SIZE_ORDER (1)
     87#endif
     88#ifdef CONFIG_PAGE_SIZE_16KB
     89#define THREAD_SIZE_ORDER (0)
     90#endif
     91#ifdef CONFIG_PAGE_SIZE_32KB
     92#define THREAD_SIZE_ORDER (0)
     93#endif
     94#ifdef CONFIG_PAGE_SIZE_64KB
     95#define THREAD_SIZE_ORDER (0)
     96#endif
     97
     98#define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
     99#define THREAD_MASK (THREAD_SIZE - 1UL)
    100
    101#define STACK_WARN	(THREAD_SIZE / 8)
    102
    103/*
    104 * thread information flags
    105 * - these are process state flags that various assembly files may need to
    106 *   access
    107 * - pending work-to-be-done flags are in LSW
    108 * - other flags in MSW
    109 */
    110#define TIF_SIGPENDING		1	/* signal pending */
    111#define TIF_NEED_RESCHED	2	/* rescheduling necessary */
    112#define TIF_SYSCALL_AUDIT	3	/* syscall auditing active */
    113#define TIF_SECCOMP		4	/* secure computing */
    114#define TIF_NOTIFY_RESUME	5	/* callback before returning to user */
    115#define TIF_UPROBE		6	/* breakpointed or singlestepping */
    116#define TIF_NOTIFY_SIGNAL	7	/* signal notifications exist */
    117#define TIF_RESTORE_SIGMASK	9	/* restore signal mask in do_signal() */
    118#define TIF_USEDFPU		16	/* FPU was used by this task this quantum (SMP) */
    119#define TIF_MEMDIE		18	/* is terminating due to OOM killer */
    120#define TIF_NOHZ		19	/* in adaptive nohz mode */
    121#define TIF_FIXADE		20	/* Fix address errors in software */
    122#define TIF_LOGADE		21	/* Log address errors to syslog */
    123#define TIF_32BIT_REGS		22	/* 32-bit general purpose registers */
    124#define TIF_32BIT_ADDR		23	/* 32-bit address space (o32/n32) */
    125#define TIF_FPUBOUND		24	/* thread bound to FPU-full CPU set */
    126#define TIF_LOAD_WATCH		25	/* If set, load watch registers */
    127#define TIF_SYSCALL_TRACEPOINT	26	/* syscall tracepoint instrumentation */
    128#define TIF_32BIT_FPREGS	27	/* 32-bit floating point registers */
    129#define TIF_HYBRID_FPREGS	28	/* 64b FP registers, odd singles in bits 63:32 of even doubles */
    130#define TIF_USEDMSA		29	/* MSA has been used this quantum */
    131#define TIF_MSA_CTX_LIVE	30	/* MSA context must be preserved */
    132#define TIF_SYSCALL_TRACE	31	/* syscall trace active */
    133
    134#define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
    135#define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
    136#define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
    137#define _TIF_SYSCALL_AUDIT	(1<<TIF_SYSCALL_AUDIT)
    138#define _TIF_SECCOMP		(1<<TIF_SECCOMP)
    139#define _TIF_NOTIFY_RESUME	(1<<TIF_NOTIFY_RESUME)
    140#define _TIF_UPROBE		(1<<TIF_UPROBE)
    141#define _TIF_NOTIFY_SIGNAL	(1<<TIF_NOTIFY_SIGNAL)
    142#define _TIF_USEDFPU		(1<<TIF_USEDFPU)
    143#define _TIF_NOHZ		(1<<TIF_NOHZ)
    144#define _TIF_FIXADE		(1<<TIF_FIXADE)
    145#define _TIF_LOGADE		(1<<TIF_LOGADE)
    146#define _TIF_32BIT_REGS		(1<<TIF_32BIT_REGS)
    147#define _TIF_32BIT_ADDR		(1<<TIF_32BIT_ADDR)
    148#define _TIF_FPUBOUND		(1<<TIF_FPUBOUND)
    149#define _TIF_LOAD_WATCH		(1<<TIF_LOAD_WATCH)
    150#define _TIF_32BIT_FPREGS	(1<<TIF_32BIT_FPREGS)
    151#define _TIF_HYBRID_FPREGS	(1<<TIF_HYBRID_FPREGS)
    152#define _TIF_USEDMSA		(1<<TIF_USEDMSA)
    153#define _TIF_MSA_CTX_LIVE	(1<<TIF_MSA_CTX_LIVE)
    154#define _TIF_SYSCALL_TRACEPOINT	(1<<TIF_SYSCALL_TRACEPOINT)
    155
    156#define _TIF_WORK_SYSCALL_ENTRY	(_TIF_NOHZ | _TIF_SYSCALL_TRACE |	\
    157				 _TIF_SYSCALL_AUDIT | \
    158				 _TIF_SYSCALL_TRACEPOINT | _TIF_SECCOMP)
    159
    160/* work to do in syscall_trace_leave() */
    161#define _TIF_WORK_SYSCALL_EXIT	(_TIF_NOHZ | _TIF_SYSCALL_TRACE |	\
    162				 _TIF_SYSCALL_AUDIT | _TIF_SYSCALL_TRACEPOINT)
    163
    164/* work to do on interrupt/exception return */
    165#define _TIF_WORK_MASK		\
    166	(_TIF_SIGPENDING | _TIF_NEED_RESCHED | _TIF_NOTIFY_RESUME |	\
    167	 _TIF_UPROBE | _TIF_NOTIFY_SIGNAL)
    168/* work to do on any return to u-space */
    169#define _TIF_ALLWORK_MASK	(_TIF_NOHZ | _TIF_WORK_MASK |		\
    170				 _TIF_WORK_SYSCALL_EXIT |		\
    171				 _TIF_SYSCALL_TRACEPOINT)
    172
    173/*
    174 * We stash processor id into a COP0 register to retrieve it fast
    175 * at kernel exception entry.
    176 */
    177#if   defined(CONFIG_MIPS_PGD_C0_CONTEXT)
    178#define SMP_CPUID_REG		20, 0	/* XCONTEXT */
    179#define ASM_SMP_CPUID_REG	$20
    180#define SMP_CPUID_PTRSHIFT	48
    181#else
    182#define SMP_CPUID_REG		4, 0	/* CONTEXT */
    183#define ASM_SMP_CPUID_REG	$4
    184#define SMP_CPUID_PTRSHIFT	23
    185#endif
    186
    187#ifdef CONFIG_64BIT
    188#define SMP_CPUID_REGSHIFT	(SMP_CPUID_PTRSHIFT + 3)
    189#else
    190#define SMP_CPUID_REGSHIFT	(SMP_CPUID_PTRSHIFT + 2)
    191#endif
    192
    193#define ASM_CPUID_MFC0		MFC0
    194#define UASM_i_CPUID_MFC0	UASM_i_MFC0
    195
    196#endif /* __KERNEL__ */
    197#endif /* _ASM_THREAD_INFO_H */