Commit 5d8544e2 authored by Palmer Dabbelt's avatar Palmer Dabbelt

RISC-V: Generic library routines and assembly

This patch contains code that is more specific to the RISC-V ISA than it
is to Linux.  It contains string and math operations, C wrappers for
various assembly instructions, stack walking code, and uaccess.
Signed-off-by: default avatarPalmer Dabbelt <palmer@dabbelt.com>
parent fab957c1
/*
* Copyright (C) 2015 Regents of the University of California
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation, version 2.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#ifndef _ASM_RISCV_ASM_H
#define _ASM_RISCV_ASM_H
#ifdef __ASSEMBLY__
#define __ASM_STR(x) x
#else
#define __ASM_STR(x) #x
#endif
#if __riscv_xlen == 64
#define __REG_SEL(a, b) __ASM_STR(a)
#elif __riscv_xlen == 32
#define __REG_SEL(a, b) __ASM_STR(b)
#else
#error "Unexpected __riscv_xlen"
#endif
#define REG_L __REG_SEL(ld, lw)
#define REG_S __REG_SEL(sd, sw)
#define SZREG __REG_SEL(8, 4)
#define LGREG __REG_SEL(3, 2)
#if __SIZEOF_POINTER__ == 8
#ifdef __ASSEMBLY__
#define RISCV_PTR .dword
#define RISCV_SZPTR 8
#define RISCV_LGPTR 3
#else
#define RISCV_PTR ".dword"
#define RISCV_SZPTR "8"
#define RISCV_LGPTR "3"
#endif
#elif __SIZEOF_POINTER__ == 4
#ifdef __ASSEMBLY__
#define RISCV_PTR .word
#define RISCV_SZPTR 4
#define RISCV_LGPTR 2
#else
#define RISCV_PTR ".word"
#define RISCV_SZPTR "4"
#define RISCV_LGPTR "2"
#endif
#else
#error "Unexpected __SIZEOF_POINTER__"
#endif
#if (__SIZEOF_INT__ == 4)
#define INT __ASM_STR(.word)
#define SZINT __ASM_STR(4)
#define LGINT __ASM_STR(2)
#else
#error "Unexpected __SIZEOF_INT__"
#endif
#if (__SIZEOF_SHORT__ == 2)
#define SHORT __ASM_STR(.half)
#define SZSHORT __ASM_STR(2)
#define LGSHORT __ASM_STR(1)
#else
#error "Unexpected __SIZEOF_SHORT__"
#endif
#endif /* _ASM_RISCV_ASM_H */
/*
* Copyright (C) 2015 Regents of the University of California
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation, version 2.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#ifndef _ASM_RISCV_CSR_H
#define _ASM_RISCV_CSR_H
#include <linux/const.h>
/* Status register flags */
#define SR_IE _AC(0x00000002, UL) /* Interrupt Enable */
#define SR_PIE _AC(0x00000020, UL) /* Previous IE */
#define SR_PS _AC(0x00000100, UL) /* Previously Supervisor */
#define SR_SUM _AC(0x00040000, UL) /* Supervisor may access User Memory */
#define SR_FS _AC(0x00006000, UL) /* Floating-point Status */
#define SR_FS_OFF _AC(0x00000000, UL)
#define SR_FS_INITIAL _AC(0x00002000, UL)
#define SR_FS_CLEAN _AC(0x00004000, UL)
#define SR_FS_DIRTY _AC(0x00006000, UL)
#define SR_XS _AC(0x00018000, UL) /* Extension Status */
#define SR_XS_OFF _AC(0x00000000, UL)
#define SR_XS_INITIAL _AC(0x00008000, UL)
#define SR_XS_CLEAN _AC(0x00010000, UL)
#define SR_XS_DIRTY _AC(0x00018000, UL)
#ifndef CONFIG_64BIT
#define SR_SD _AC(0x80000000, UL) /* FS/XS dirty */
#else
#define SR_SD _AC(0x8000000000000000, UL) /* FS/XS dirty */
#endif
/* SPTBR flags */
#if __riscv_xlen == 32
#define SPTBR_PPN _AC(0x003FFFFF, UL)
#define SPTBR_MODE_32 _AC(0x80000000, UL)
#define SPTBR_MODE SPTBR_MODE_32
#else
#define SPTBR_PPN _AC(0x00000FFFFFFFFFFF, UL)
#define SPTBR_MODE_39 _AC(0x8000000000000000, UL)
#define SPTBR_MODE SPTBR_MODE_39
#endif
/* Interrupt Enable and Interrupt Pending flags */
#define SIE_SSIE _AC(0x00000002, UL) /* Software Interrupt Enable */
#define SIE_STIE _AC(0x00000020, UL) /* Timer Interrupt Enable */
#define EXC_INST_MISALIGNED 0
#define EXC_INST_ACCESS 1
#define EXC_BREAKPOINT 3
#define EXC_LOAD_ACCESS 5
#define EXC_STORE_ACCESS 7
#define EXC_SYSCALL 8
#define EXC_INST_PAGE_FAULT 12
#define EXC_LOAD_PAGE_FAULT 13
#define EXC_STORE_PAGE_FAULT 15
#ifndef __ASSEMBLY__
#define csr_swap(csr, val) \
({ \
unsigned long __v = (unsigned long)(val); \
__asm__ __volatile__ ("csrrw %0, " #csr ", %1" \
: "=r" (__v) : "rK" (__v) \
: "memory"); \
__v; \
})
#define csr_read(csr) \
({ \
register unsigned long __v; \
__asm__ __volatile__ ("csrr %0, " #csr \
: "=r" (__v) : \
: "memory"); \
__v; \
})
#define csr_write(csr, val) \
({ \
unsigned long __v = (unsigned long)(val); \
__asm__ __volatile__ ("csrw " #csr ", %0" \
: : "rK" (__v) \
: "memory"); \
})
#define csr_read_set(csr, val) \
({ \
unsigned long __v = (unsigned long)(val); \
__asm__ __volatile__ ("csrrs %0, " #csr ", %1" \
: "=r" (__v) : "rK" (__v) \
: "memory"); \
__v; \
})
#define csr_set(csr, val) \
({ \
unsigned long __v = (unsigned long)(val); \
__asm__ __volatile__ ("csrs " #csr ", %0" \
: : "rK" (__v) \
: "memory"); \
})
#define csr_read_clear(csr, val) \
({ \
unsigned long __v = (unsigned long)(val); \
__asm__ __volatile__ ("csrrc %0, " #csr ", %1" \
: "=r" (__v) : "rK" (__v) \
: "memory"); \
__v; \
})
#define csr_clear(csr, val) \
({ \
unsigned long __v = (unsigned long)(val); \
__asm__ __volatile__ ("csrc " #csr ", %0" \
: : "rK" (__v) \
: "memory"); \
})
#endif /* __ASSEMBLY__ */
#endif /* _ASM_RISCV_CSR_H */
/*
* Copyright (C) 2015 Regents of the University of California
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation, version 2.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#ifndef _ASM_RISCV_LINKAGE_H
#define _ASM_RISCV_LINKAGE_H
#define __ALIGN .balign 4
#define __ALIGN_STR ".balign 4"
#endif /* _ASM_RISCV_LINKAGE_H */
/*
* Copyright (C) 2013 Regents of the University of California
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation, version 2.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#ifndef _ASM_RISCV_STRING_H
#define _ASM_RISCV_STRING_H
#include <linux/types.h>
#include <linux/linkage.h>
#define __HAVE_ARCH_MEMSET
extern asmlinkage void *memset(void *, int, size_t);
#define __HAVE_ARCH_MEMCPY
extern asmlinkage void *memcpy(void *, const void *, size_t);
#endif /* _ASM_RISCV_STRING_H */
/*
* Copyright (C) 2012 Regents of the University of California
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation, version 2.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* This file was copied from include/asm-generic/uaccess.h
*/
#ifndef _ASM_RISCV_UACCESS_H
#define _ASM_RISCV_UACCESS_H
/*
* User space memory access functions
*/
#include <linux/errno.h>
#include <linux/compiler.h>
#include <linux/thread_info.h>
#include <asm/byteorder.h>
#include <asm/asm.h>
#define __enable_user_access() \
__asm__ __volatile__ ("csrs sstatus, %0" : : "r" (SR_SUM) : "memory")
#define __disable_user_access() \
__asm__ __volatile__ ("csrc sstatus, %0" : : "r" (SR_SUM) : "memory")
/*
* The fs value determines whether argument validity checking should be
* performed or not. If get_fs() == USER_DS, checking is performed, with
* get_fs() == KERNEL_DS, checking is bypassed.
*
* For historical reasons, these macros are grossly misnamed.
*/
#define KERNEL_DS (~0UL)
#define USER_DS (TASK_SIZE)
#define get_ds() (KERNEL_DS)
#define get_fs() (current_thread_info()->addr_limit)
static inline void set_fs(mm_segment_t fs)
{
current_thread_info()->addr_limit = fs;
}
#define segment_eq(a, b) ((a) == (b))
#define user_addr_max() (get_fs())
#define VERIFY_READ 0
#define VERIFY_WRITE 1
/**
* access_ok: - Checks if a user space pointer is valid
* @type: Type of access: %VERIFY_READ or %VERIFY_WRITE. Note that
* %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe
* to write to a block, it is always safe to read from it.
* @addr: User space pointer to start of block to check
* @size: Size of block to check
*
* Context: User context only. This function may sleep.
*
* Checks if a pointer to a block of memory in user space is valid.
*
* Returns true (nonzero) if the memory block may be valid, false (zero)
* if it is definitely invalid.
*
* Note that, depending on architecture, this function probably just
* checks that the pointer is in the user space range - after calling
* this function, memory access functions may still return -EFAULT.
*/
#define access_ok(type, addr, size) ({ \
__chk_user_ptr(addr); \
likely(__access_ok((unsigned long __force)(addr), (size))); \
})
/*
* Ensure that the range [addr, addr+size) is within the process's
* address space
*/
static inline int __access_ok(unsigned long addr, unsigned long size)
{
const mm_segment_t fs = get_fs();
return (size <= fs) && (addr <= (fs - size));
}
/*
* The exception table consists of pairs of addresses: the first is the
* address of an instruction that is allowed to fault, and the second is
* the address at which the program should continue. No registers are
* modified, so it is entirely up to the continuation code to figure out
* what to do.
*
* All the routines below use bits of fixup code that are out of line
* with the main instruction path. This means when everything is well,
* we don't even have to jump over them. Further, they do not intrude
* on our cache or tlb entries.
*/
struct exception_table_entry {
unsigned long insn, fixup;
};
extern int fixup_exception(struct pt_regs *state);
#if defined(__LITTLE_ENDIAN)
#define __MSW 1
#define __LSW 0
#elif defined(__BIG_ENDIAN)
#define __MSW 0
#define __LSW 1
#else
#error "Unknown endianness"
#endif
/*
* The "__xxx" versions of the user access functions do not verify the address
* space - it must have been done previously with a separate "access_ok()"
* call.
*/
#ifdef CONFIG_MMU
#define __get_user_asm(insn, x, ptr, err) \
do { \
uintptr_t __tmp; \
__typeof__(x) __x; \
__enable_user_access(); \
__asm__ __volatile__ ( \
"1:\n" \
" " insn " %1, %3\n" \
"2:\n" \
" .section .fixup,\"ax\"\n" \
" .balign 4\n" \
"3:\n" \
" li %0, %4\n" \
" li %1, 0\n" \
" jump 2b, %2\n" \
" .previous\n" \
" .section __ex_table,\"a\"\n" \
" .balign " RISCV_SZPTR "\n" \
" " RISCV_PTR " 1b, 3b\n" \
" .previous" \
: "+r" (err), "=&r" (__x), "=r" (__tmp) \
: "m" (*(ptr)), "i" (-EFAULT)); \
__disable_user_access(); \
(x) = __x; \
} while (0)
#endif /* CONFIG_MMU */
#ifdef CONFIG_64BIT
#define __get_user_8(x, ptr, err) \
__get_user_asm("ld", x, ptr, err)
#else /* !CONFIG_64BIT */
#ifdef CONFIG_MMU
#define __get_user_8(x, ptr, err) \
do { \
u32 __user *__ptr = (u32 __user *)(ptr); \
u32 __lo, __hi; \
uintptr_t __tmp; \
__enable_user_access(); \
__asm__ __volatile__ ( \
"1:\n" \
" lw %1, %4\n" \
"2:\n" \
" lw %2, %5\n" \
"3:\n" \
" .section .fixup,\"ax\"\n" \
" .balign 4\n" \
"4:\n" \
" li %0, %6\n" \
" li %1, 0\n" \
" li %2, 0\n" \
" jump 3b, %3\n" \
" .previous\n" \
" .section __ex_table,\"a\"\n" \
" .balign " RISCV_SZPTR "\n" \
" " RISCV_PTR " 1b, 4b\n" \
" " RISCV_PTR " 2b, 4b\n" \
" .previous" \
: "+r" (err), "=&r" (__lo), "=r" (__hi), \
"=r" (__tmp) \
: "m" (__ptr[__LSW]), "m" (__ptr[__MSW]), \
"i" (-EFAULT)); \
__disable_user_access(); \
(x) = (__typeof__(x))((__typeof__((x)-(x)))( \
(((u64)__hi << 32) | __lo))); \
} while (0)
#endif /* CONFIG_MMU */
#endif /* CONFIG_64BIT */
/**
* __get_user: - Get a simple variable from user space, with less checking.
* @x: Variable to store result.
* @ptr: Source address, in user space.
*
* Context: User context only. This function may sleep.
*
* This macro copies a single simple variable from user space to kernel
* space. It supports simple types like char and int, but not larger
* data types like structures or arrays.
*
* @ptr must have pointer-to-simple-variable type, and the result of
* dereferencing @ptr must be assignable to @x without a cast.
*
* Caller must check the pointer with access_ok() before calling this
* function.
*
* Returns zero on success, or -EFAULT on error.
* On error, the variable @x is set to zero.
*/
#define __get_user(x, ptr) \
({ \
register long __gu_err = 0; \
const __typeof__(*(ptr)) __user *__gu_ptr = (ptr); \
__chk_user_ptr(__gu_ptr); \
switch (sizeof(*__gu_ptr)) { \
case 1: \
__get_user_asm("lb", (x), __gu_ptr, __gu_err); \
break; \
case 2: \
__get_user_asm("lh", (x), __gu_ptr, __gu_err); \
break; \
case 4: \
__get_user_asm("lw", (x), __gu_ptr, __gu_err); \
break; \
case 8: \
__get_user_8((x), __gu_ptr, __gu_err); \
break; \
default: \
BUILD_BUG(); \
} \
__gu_err; \
})
/**
* get_user: - Get a simple variable from user space.
* @x: Variable to store result.
* @ptr: Source address, in user space.
*
* Context: User context only. This function may sleep.
*
* This macro copies a single simple variable from user space to kernel
* space. It supports simple types like char and int, but not larger
* data types like structures or arrays.
*
* @ptr must have pointer-to-simple-variable type, and the result of
* dereferencing @ptr must be assignable to @x without a cast.
*
* Returns zero on success, or -EFAULT on error.
* On error, the variable @x is set to zero.
*/
#define get_user(x, ptr) \
({ \
const __typeof__(*(ptr)) __user *__p = (ptr); \
might_fault(); \
access_ok(VERIFY_READ, __p, sizeof(*__p)) ? \
__get_user((x), __p) : \
((x) = 0, -EFAULT); \
})
#ifdef CONFIG_MMU
#define __put_user_asm(insn, x, ptr, err) \
do { \
uintptr_t __tmp; \
__typeof__(*(ptr)) __x = x; \
__enable_user_access(); \
__asm__ __volatile__ ( \
"1:\n" \
" " insn " %z3, %2\n" \
"2:\n" \
" .section .fixup,\"ax\"\n" \
" .balign 4\n" \
"3:\n" \
" li %0, %4\n" \
" jump 2b, %1\n" \
" .previous\n" \
" .section __ex_table,\"a\"\n" \
" .balign " RISCV_SZPTR "\n" \
" " RISCV_PTR " 1b, 3b\n" \
" .previous" \
: "+r" (err), "=r" (__tmp), "=m" (*(ptr)) \
: "rJ" (__x), "i" (-EFAULT)); \
__disable_user_access(); \
} while (0)
#endif /* CONFIG_MMU */
#ifdef CONFIG_64BIT
#define __put_user_8(x, ptr, err) \
__put_user_asm("sd", x, ptr, err)
#else /* !CONFIG_64BIT */
#ifdef CONFIG_MMU
#define __put_user_8(x, ptr, err) \
do { \
u32 __user *__ptr = (u32 __user *)(ptr); \
u64 __x = (__typeof__((x)-(x)))(x); \
uintptr_t __tmp; \
__enable_user_access(); \
__asm__ __volatile__ ( \
"1:\n" \
" sw %z4, %2\n" \
"2:\n" \
" sw %z5, %3\n" \
"3:\n" \
" .section .fixup,\"ax\"\n" \
" .balign 4\n" \
"4:\n" \
" li %0, %6\n" \
" jump 2b, %1\n" \
" .previous\n" \
" .section __ex_table,\"a\"\n" \
" .balign " RISCV_SZPTR "\n" \
" " RISCV_PTR " 1b, 4b\n" \
" " RISCV_PTR " 2b, 4b\n" \
" .previous" \
: "+r" (err), "=r" (__tmp), \
"=m" (__ptr[__LSW]), \
"=m" (__ptr[__MSW]) \
: "rJ" (__x), "rJ" (__x >> 32), "i" (-EFAULT)); \
__disable_user_access(); \
} while (0)
#endif /* CONFIG_MMU */
#endif /* CONFIG_64BIT */
/**
* __put_user: - Write a simple value into user space, with less checking.
* @x: Value to copy to user space.
* @ptr: Destination address, in user space.
*
* Context: User context only. This function may sleep.
*
* This macro copies a single simple value from kernel space to user
* space. It supports simple types like char and int, but not larger
* data types like structures or arrays.
*
* @ptr must have pointer-to-simple-variable type, and @x must be assignable
* to the result of dereferencing @ptr.
*
* Caller must check the pointer with access_ok() before calling this
* function.
*
* Returns zero on success, or -EFAULT on error.
*/
#define __put_user(x, ptr) \
({ \
register long __pu_err = 0; \
__typeof__(*(ptr)) __user *__gu_ptr = (ptr); \
__chk_user_ptr(__gu_ptr); \
switch (sizeof(*__gu_ptr)) { \
case 1: \
__put_user_asm("sb", (x), __gu_ptr, __pu_err); \
break; \
case 2: \
__put_user_asm("sh", (x), __gu_ptr, __pu_err); \
break; \
case 4: \
__put_user_asm("sw", (x), __gu_ptr, __pu_err); \
break; \
case 8: \
__put_user_8((x), __gu_ptr, __pu_err); \
break; \
default: \
BUILD_BUG(); \
} \
__pu_err; \
})
/**
* put_user: - Write a simple value into user space.
* @x: Value to copy to user space.
* @ptr: Destination address, in user space.
*
* Context: User context only. This function may sleep.
*
* This macro copies a single simple value from kernel space to user
* space. It supports simple types like char and int, but not larger
* data types like structures or arrays.
*
* @ptr must have pointer-to-simple-variable type, and @x must be assignable
* to the result of dereferencing @ptr.
*
* Returns zero on success, or -EFAULT on error.
*/
#define put_user(x, ptr) \
({ \
__typeof__(*(ptr)) __user *__p = (ptr); \
might_fault(); \
access_ok(VERIFY_WRITE, __p, sizeof(*__p)) ? \
__put_user((x), __p) : \
-EFAULT; \
})
extern unsigned long __must_check __copy_user(void __user *to,
const void __user *from, unsigned long n);
static inline unsigned long
raw_copy_from_user(void *to, const void __user *from, unsigned long n)
{
return __copy_user(to, from, n);
}
static inline unsigned long
raw_copy_to_user(void __user *to, const void *from, unsigned long n)
{
return __copy_user(to, from, n);
}
extern long strncpy_from_user(char *dest, const char __user *src, long count);
extern long __must_check strlen_user(const char __user *str);
extern long __must_check strnlen_user(const char __user *str, long n);
extern
unsigned long __must_check __clear_user(void __user *addr, unsigned long n);
static inline
unsigned long __must_check clear_user(void __user *to, unsigned long n)
{
might_fault();
return access_ok(VERIFY_WRITE, to, n) ?
__clear_user(to, n) : n;
}
/*
* Atomic compare-and-exchange, but with a fixup for userspace faults. Faults
* will set "err" to -EFAULT, while successful accesses return the previous
* value.
*/
#ifdef CONFIG_MMU
#define __cmpxchg_user(ptr, old, new, err, size, lrb, scb) \
({ \
__typeof__(ptr) __ptr = (ptr); \
__typeof__(*(ptr)) __old = (old); \
__typeof__(*(ptr)) __new = (new); \
__typeof__(*(ptr)) __ret; \
__typeof__(err) __err = 0; \
register unsigned int __rc; \
__enable_user_access(); \
switch (size) { \
case 4: \
__asm__ __volatile__ ( \
"0:\n" \
" lr.w" #scb " %[ret], %[ptr]\n" \
" bne %[ret], %z[old], 1f\n" \
" sc.w" #lrb " %[rc], %z[new], %[ptr]\n" \
" bnez %[rc], 0b\n" \
"1:\n" \
".section .fixup,\"ax\"\n" \
".balign 4\n" \
"2:\n" \
" li %[err], %[efault]\n" \
" jump 1b, %[rc]\n" \
".previous\n" \
".section __ex_table,\"a\"\n" \
".balign " RISCV_SZPTR "\n" \
" " RISCV_PTR " 1b, 2b\n" \
".previous\n" \
: [ret] "=&r" (__ret), \
[rc] "=&r" (__rc), \
[ptr] "+A" (*__ptr), \
[err] "=&r" (__err) \
: [old] "rJ" (__old), \
[new] "rJ" (__new), \
[efault] "i" (-EFAULT)); \
break; \
case 8: \
__asm__ __volatile__ ( \
"0:\n" \
" lr.d" #scb " %[ret], %[ptr]\n" \
" bne %[ret], %z[old], 1f\n" \
" sc.d" #lrb " %[rc], %z[new], %[ptr]\n" \
" bnez %[rc], 0b\n" \
"1:\n" \
".section .fixup,\"ax\"\n" \
".balign 4\n" \
"2:\n" \
" li %[err], %[efault]\n" \
" jump 1b, %[rc]\n" \
".previous\n" \
".section __ex_table,\"a\"\n" \
".balign " RISCV_SZPTR "\n" \
" " RISCV_PTR " 1b, 2b\n" \
".previous\n" \
: [ret] "=&r" (__ret), \
[rc] "=&r" (__rc), \
[ptr] "+A" (*__ptr), \
[err] "=&r" (__err) \
: [old] "rJ" (__old), \
[new] "rJ" (__new), \
[efault] "i" (-EFAULT)); \
break; \
default: \
BUILD_BUG(); \
} \
__disable_user_access(); \
(err) = __err; \
__ret; \
})
#endif /* CONFIG_MMU */
#endif /* _ASM_RISCV_UACCESS_H */
/*
* Copyright (C) 2012 Regents of the University of California
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation, version 2.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
* Derived from arch/x86/include/asm/word-at-a-time.h
*/
#ifndef _ASM_RISCV_WORD_AT_A_TIME_H
#define _ASM_RISCV_WORD_AT_A_TIME_H
#include <linux/kernel.h>
struct word_at_a_time {
const unsigned long one_bits, high_bits;
};
#define WORD_AT_A_TIME_CONSTANTS { REPEAT_BYTE(0x01), REPEAT_BYTE(0x80) }
static inline unsigned long has_zero(unsigned long val,
unsigned long *bits, const struct word_at_a_time *c)
{
unsigned long mask = ((val - c->one_bits) & ~val) & c->high_bits;
*bits = mask;
return mask;
}
static inline unsigned long prep_zero_mask(unsigned long val,
unsigned long bits, const struct word_at_a_time *c)
{
return bits;
}
static inline unsigned long create_zero_mask(unsigned long bits)
{
bits = (bits - 1) & ~bits;
return bits >> 7;
}
static inline unsigned long find_zero(unsigned long mask)
{
return fls64(mask) >> 3;
}
/* The mask we created is directly usable as a bytemask */
#define zero_bytemask(mask) (mask)
#endif /* _ASM_RISCV_WORD_AT_A_TIME_H */
/*
* Copyright (C) 2008 ARM Limited
* Copyright (C) 2014 Regents of the University of California
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/export.h>
#include <linux/kallsyms.h>
#include <linux/sched.h>
#include <linux/sched/debug.h>
#include <linux/sched/task_stack.h>
#include <linux/stacktrace.h>
#ifdef CONFIG_FRAME_POINTER
struct stackframe {
unsigned long fp;
unsigned long ra;
};
static void notrace walk_stackframe(struct task_struct *task,
struct pt_regs *regs, bool (*fn)(unsigned long, void *), void *arg)
{
unsigned long fp, sp, pc;
if (regs) {
fp = GET_FP(regs);
sp = GET_USP(regs);
pc = GET_IP(regs);
} else if (task == NULL || task == current) {
const register unsigned long current_sp __asm__ ("sp");
fp = (unsigned long)__builtin_frame_address(0);
sp = current_sp;
pc = (unsigned long)walk_stackframe;
} else {
/* task blocked in __switch_to */
fp = task->thread.s[0];
sp = task->thread.sp;
pc = task->thread.ra;
}
for (;;) {
unsigned long low, high;
struct stackframe *frame;
if (unlikely(!__kernel_text_address(pc) || fn(pc, arg)))
break;
/* Validate frame pointer */
low = sp + sizeof(struct stackframe);
high = ALIGN(sp, THREAD_SIZE);
if (unlikely(fp < low || fp > high || fp & 0x7))
break;
/* Unwind stack frame */
frame = (struct stackframe *)fp - 1;
sp = fp;
fp = frame->fp;
pc = frame->ra - 0x4;
}
}
#else /* !CONFIG_FRAME_POINTER */
static void notrace walk_stackframe(struct task_struct *task,
struct pt_regs *regs, bool (*fn)(unsigned long, void *), void *arg)
{
unsigned long sp, pc;
unsigned long *ksp;
if (regs) {
sp = GET_USP(regs);
pc = GET_IP(regs);
} else if (task == NULL || task == current) {
const register unsigned long current_sp __asm__ ("sp");
sp = current_sp;
pc = (unsigned long)walk_stackframe;
} else {
/* task blocked in __switch_to */
sp = task->thread.sp;
pc = task->thread.ra;
}
if (unlikely(sp & 0x7))
return;
ksp = (unsigned long *)sp;
while (!kstack_end(ksp)) {
if (__kernel_text_address(pc) && unlikely(fn(pc, arg)))
break;
pc = (*ksp++) - 0x4;
}
}
#endif /* CONFIG_FRAME_POINTER */
static bool print_trace_address(unsigned long pc, void *arg)
{
print_ip_sym(pc);
return false;
}
void show_stack(struct task_struct *task, unsigned long *sp)
{
pr_cont("Call Trace:\n");
walk_stackframe(task, NULL, print_trace_address, NULL);
}
static bool save_wchan(unsigned long pc, void *arg)
{
if (!in_sched_functions(pc)) {
unsigned long *p = arg;
*p = pc;
return true;
}
return false;
}
unsigned long get_wchan(struct task_struct *task)
{
unsigned long pc = 0;
if (likely(task && task != current && task->state != TASK_RUNNING))
walk_stackframe(task, NULL, save_wchan, &pc);
return pc;
}
#ifdef CONFIG_STACKTRACE
static bool __save_trace(unsigned long pc, void *arg, bool nosched)
{
struct stack_trace *trace = arg;
if (unlikely(nosched && in_sched_functions(pc)))
return false;
if (unlikely(trace->skip > 0)) {
trace->skip--;
return false;
}
trace->entries[trace->nr_entries++] = pc;
return (trace->nr_entries >= trace->max_entries);
}
static bool save_trace(unsigned long pc, void *arg)
{
return __save_trace(pc, arg, false);
}
/*
* Save stack-backtrace addresses into a stack_trace buffer.
*/
void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
{
walk_stackframe(tsk, NULL, save_trace, trace);
if (trace->nr_entries < trace->max_entries)
trace->entries[trace->nr_entries++] = ULONG_MAX;
}
EXPORT_SYMBOL_GPL(save_stack_trace_tsk);
void save_stack_trace(struct stack_trace *trace)
{
save_stack_trace_tsk(NULL, trace);
}
EXPORT_SYMBOL_GPL(save_stack_trace);
#endif /* CONFIG_STACKTRACE */
/*
* Copyright (C) 2013 Regents of the University of California
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation, version 2.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/linkage.h>
#include <asm/asm.h>
/* void *memcpy(void *, const void *, size_t) */
ENTRY(memcpy)
move t6, a0 /* Preserve return value */
/* Defer to byte-oriented copy for small sizes */
sltiu a3, a2, 128
bnez a3, 4f
/* Use word-oriented copy only if low-order bits match */
andi a3, t6, SZREG-1
andi a4, a1, SZREG-1
bne a3, a4, 4f
beqz a3, 2f /* Skip if already aligned */
/*
* Round to nearest double word-aligned address
* greater than or equal to start address
*/
andi a3, a1, ~(SZREG-1)
addi a3, a3, SZREG
/* Handle initial misalignment */
sub a4, a3, a1
1:
lb a5, 0(a1)
addi a1, a1, 1
sb a5, 0(t6)
addi t6, t6, 1
bltu a1, a3, 1b
sub a2, a2, a4 /* Update count */
2:
andi a4, a2, ~((16*SZREG)-1)
beqz a4, 4f
add a3, a1, a4
3:
REG_L a4, 0(a1)
REG_L a5, SZREG(a1)
REG_L a6, 2*SZREG(a1)
REG_L a7, 3*SZREG(a1)
REG_L t0, 4*SZREG(a1)
REG_L t1, 5*SZREG(a1)
REG_L t2, 6*SZREG(a1)
REG_L t3, 7*SZREG(a1)
REG_L t4, 8*SZREG(a1)
REG_L t5, 9*SZREG(a1)
REG_S a4, 0(t6)
REG_S a5, SZREG(t6)
REG_S a6, 2*SZREG(t6)
REG_S a7, 3*SZREG(t6)
REG_S t0, 4*SZREG(t6)
REG_S t1, 5*SZREG(t6)
REG_S t2, 6*SZREG(t6)
REG_S t3, 7*SZREG(t6)
REG_S t4, 8*SZREG(t6)
REG_S t5, 9*SZREG(t6)
REG_L a4, 10*SZREG(a1)
REG_L a5, 11*SZREG(a1)
REG_L a6, 12*SZREG(a1)
REG_L a7, 13*SZREG(a1)
REG_L t0, 14*SZREG(a1)
REG_L t1, 15*SZREG(a1)
addi a1, a1, 16*SZREG
REG_S a4, 10*SZREG(t6)
REG_S a5, 11*SZREG(t6)
REG_S a6, 12*SZREG(t6)
REG_S a7, 13*SZREG(t6)
REG_S t0, 14*SZREG(t6)
REG_S t1, 15*SZREG(t6)
addi t6, t6, 16*SZREG
bltu a1, a3, 3b
andi a2, a2, (16*SZREG)-1 /* Update count */
4:
/* Handle trailing misalignment */
beqz a2, 6f
add a3, a1, a2
/* Use word-oriented copy if co-aligned to word boundary */
or a5, a1, t6
or a5, a5, a3
andi a5, a5, 3
bnez a5, 5f
7:
lw a4, 0(a1)
addi a1, a1, 4
sw a4, 0(t6)
addi t6, t6, 4
bltu a1, a3, 7b
ret
5:
lb a4, 0(a1)
addi a1, a1, 1
sb a4, 0(t6)
addi t6, t6, 1
bltu a1, a3, 5b
6:
ret
END(memcpy)
/*
* Copyright (C) 2013 Regents of the University of California
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation, version 2.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/linkage.h>
#include <asm/asm.h>
/* void *memset(void *, int, size_t) */
ENTRY(memset)
move t0, a0 /* Preserve return value */
/* Defer to byte-oriented fill for small sizes */
sltiu a3, a2, 16
bnez a3, 4f
/*
* Round to nearest XLEN-aligned address
* greater than or equal to start address
*/
addi a3, t0, SZREG-1
andi a3, a3, ~(SZREG-1)
beq a3, t0, 2f /* Skip if already aligned */
/* Handle initial misalignment */
sub a4, a3, t0
1:
sb a1, 0(t0)
addi t0, t0, 1
bltu t0, a3, 1b
sub a2, a2, a4 /* Update count */
2: /* Duff's device with 32 XLEN stores per iteration */
/* Broadcast value into all bytes */
andi a1, a1, 0xff
slli a3, a1, 8
or a1, a3, a1
slli a3, a1, 16
or a1, a3, a1
#ifdef CONFIG_64BIT
slli a3, a1, 32
or a1, a3, a1
#endif
/* Calculate end address */
andi a4, a2, ~(SZREG-1)
add a3, t0, a4
andi a4, a4, 31*SZREG /* Calculate remainder */
beqz a4, 3f /* Shortcut if no remainder */
neg a4, a4
addi a4, a4, 32*SZREG /* Calculate initial offset */
/* Adjust start address with offset */
sub t0, t0, a4
/* Jump into loop body */
/* Assumes 32-bit instruction lengths */
la a5, 3f
#ifdef CONFIG_64BIT
srli a4, a4, 1
#endif
add a5, a5, a4
jr a5
3:
REG_S a1, 0(t0)
REG_S a1, SZREG(t0)
REG_S a1, 2*SZREG(t0)
REG_S a1, 3*SZREG(t0)
REG_S a1, 4*SZREG(t0)
REG_S a1, 5*SZREG(t0)
REG_S a1, 6*SZREG(t0)
REG_S a1, 7*SZREG(t0)
REG_S a1, 8*SZREG(t0)
REG_S a1, 9*SZREG(t0)
REG_S a1, 10*SZREG(t0)
REG_S a1, 11*SZREG(t0)
REG_S a1, 12*SZREG(t0)
REG_S a1, 13*SZREG(t0)
REG_S a1, 14*SZREG(t0)
REG_S a1, 15*SZREG(t0)
REG_S a1, 16*SZREG(t0)
REG_S a1, 17*SZREG(t0)
REG_S a1, 18*SZREG(t0)
REG_S a1, 19*SZREG(t0)
REG_S a1, 20*SZREG(t0)
REG_S a1, 21*SZREG(t0)
REG_S a1, 22*SZREG(t0)
REG_S a1, 23*SZREG(t0)
REG_S a1, 24*SZREG(t0)
REG_S a1, 25*SZREG(t0)
REG_S a1, 26*SZREG(t0)
REG_S a1, 27*SZREG(t0)
REG_S a1, 28*SZREG(t0)
REG_S a1, 29*SZREG(t0)
REG_S a1, 30*SZREG(t0)
REG_S a1, 31*SZREG(t0)
addi t0, t0, 32*SZREG
bltu t0, a3, 3b
andi a2, a2, SZREG-1 /* Update count */
4:
/* Handle trailing misalignment */
beqz a2, 6f
add a3, t0, a2
5:
sb a1, 0(t0)
addi t0, t0, 1
bltu t0, a3, 5b
6:
ret
END(memset)
#include <linux/linkage.h>
#include <asm/asm.h>
#include <asm/csr.h>
.altmacro
.macro fixup op reg addr lbl
LOCAL _epc
_epc:
\op \reg, \addr
.section __ex_table,"a"
.balign RISCV_SZPTR
RISCV_PTR _epc, \lbl
.previous
.endm
ENTRY(__copy_user)
/* Enable access to user memory */
li t6, SR_SUM
csrs sstatus, t6
add a3, a1, a2
/* Use word-oriented copy only if low-order bits match */
andi t0, a0, SZREG-1
andi t1, a1, SZREG-1
bne t0, t1, 2f
addi t0, a1, SZREG-1
andi t1, a3, ~(SZREG-1)
andi t0, t0, ~(SZREG-1)
/*
* a3: terminal address of source region
* t0: lowest XLEN-aligned address in source
* t1: highest XLEN-aligned address in source
*/
bgeu t0, t1, 2f
bltu a1, t0, 4f
1:
fixup REG_L, t2, (a1), 10f
fixup REG_S, t2, (a0), 10f
addi a1, a1, SZREG
addi a0, a0, SZREG
bltu a1, t1, 1b
2:
bltu a1, a3, 5f
3:
/* Disable access to user memory */
csrc sstatus, t6
li a0, 0
ret
4: /* Edge case: unalignment */
fixup lbu, t2, (a1), 10f
fixup sb, t2, (a0), 10f
addi a1, a1, 1
addi a0, a0, 1
bltu a1, t0, 4b
j 1b
5: /* Edge case: remainder */
fixup lbu, t2, (a1), 10f
fixup sb, t2, (a0), 10f
addi a1, a1, 1
addi a0, a0, 1
bltu a1, a3, 5b
j 3b
ENDPROC(__copy_user)
ENTRY(__clear_user)
/* Enable access to user memory */
li t6, SR_SUM
csrs sstatus, t6
add a3, a0, a1
addi t0, a0, SZREG-1
andi t1, a3, ~(SZREG-1)
andi t0, t0, ~(SZREG-1)
/*
* a3: terminal address of target region
* t0: lowest doubleword-aligned address in target region
* t1: highest doubleword-aligned address in target region
*/
bgeu t0, t1, 2f
bltu a0, t0, 4f
1:
fixup REG_S, zero, (a0), 10f
addi a0, a0, SZREG
bltu a0, t1, 1b
2:
bltu a0, a3, 5f
3:
/* Disable access to user memory */
csrc sstatus, t6
li a0, 0
ret
4: /* Edge case: unalignment */
fixup sb, zero, (a0), 10f
addi a0, a0, 1
bltu a0, t0, 4b
j 1b
5: /* Edge case: remainder */
fixup sb, zero, (a0), 10f
addi a0, a0, 1
bltu a0, a3, 5b
j 3b
ENDPROC(__clear_user)
.section .fixup,"ax"
.balign 4
10:
/* Disable access to user memory */
csrs sstatus, t6
sub a0, a3, a0
ret
.previous
/*
* Copyright (C) 2016-2017 Free Software Foundation, Inc.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation, version 2.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
.globl __udivdi3
__udivdi3:
mv a2, a1
mv a1, a0
li a0, -1
beqz a2, .L5
li a3, 1
bgeu a2, a1, .L2
.L1:
blez a2, .L2
slli a2, a2, 1
slli a3, a3, 1
bgtu a1, a2, .L1
.L2:
li a0, 0
.L3:
bltu a1, a2, .L4
sub a1, a1, a2
or a0, a0, a3
.L4:
srli a3, a3, 1
srli a2, a2, 1
bnez a3, .L3
.L5:
ret
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