diff options
Diffstat (limited to 'arch/csky/include/asm/uaccess.h')
| -rw-r--r-- | arch/csky/include/asm/uaccess.h | 416 |
1 files changed, 416 insertions, 0 deletions
diff --git a/arch/csky/include/asm/uaccess.h b/arch/csky/include/asm/uaccess.h new file mode 100644 index 0000000000000..acaf0e210d81c --- /dev/null +++ b/arch/csky/include/asm/uaccess.h @@ -0,0 +1,416 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd. + +#ifndef __ASM_CSKY_UACCESS_H +#define __ASM_CSKY_UACCESS_H + +/* + * User space memory access functions + */ +#include <linux/compiler.h> +#include <linux/errno.h> +#include <linux/types.h> +#include <linux/sched.h> +#include <linux/mm.h> +#include <linux/string.h> +#include <linux/version.h> +#include <asm/segment.h> + +#define VERIFY_READ 0 +#define VERIFY_WRITE 1 + +static inline int access_ok(int type, const void *addr, unsigned long size) +{ + unsigned long limit = current_thread_info()->addr_limit.seg; + + return (((unsigned long)addr < limit) && + ((unsigned long)(addr + size) < limit)); +} + +static inline int verify_area(int type, const void *addr, unsigned long size) +{ + return access_ok(type, addr, size) ? 0 : -EFAULT; +} + +#define __addr_ok(addr) (access_ok(VERIFY_READ, addr, 0)) + +extern int __put_user_bad(void); + +/* + * Tell gcc we read from memory instead of writing: this is because + * we do not write to any memory gcc knows about, so there are no + * aliasing issues. + */ + +/* + * These are the main single-value transfer routines. They automatically + * use the right size if we just have the right pointer type. + * + * This gets kind of ugly. We want to return _two_ values in "get_user()" + * and yet we don't want to do any pointers, because that is too much + * of a performance impact. Thus we have a few rather ugly macros here, + * and hide all the ugliness from the user. + * + * The "__xxx" versions of the user access functions are versions that + * do not verify the address space, that must have been done previously + * with a separate "access_ok()" call (this is used when we do multiple + * accesses to the same area of user memory). + * + * As we use the same address space for kernel and user data on + * Ckcore, we can just do these as direct assignments. (Of course, the + * exception handling means that it's no longer "just"...) + */ + +#define put_user(x, ptr) \ + __put_user_check((x), (ptr), sizeof(*(ptr))) + +#define __put_user(x, ptr) \ + __put_user_nocheck((x), (ptr), sizeof(*(ptr))) + +#define __ptr(x) ((unsigned long *)(x)) + +#define get_user(x, ptr) \ + __get_user_check((x), (ptr), sizeof(*(ptr))) + +#define __get_user(x, ptr) \ + __get_user_nocheck((x), (ptr), sizeof(*(ptr))) + +#define __put_user_nocheck(x, ptr, size) \ +({ \ + long __pu_err = 0; \ + typeof(*(ptr)) *__pu_addr = (ptr); \ + typeof(*(ptr)) __pu_val = (typeof(*(ptr)))(x); \ + if (__pu_addr) \ + __put_user_size(__pu_val, (__pu_addr), (size), \ + __pu_err); \ + __pu_err; \ +}) + +#define __put_user_check(x, ptr, size) \ +({ \ + long __pu_err = -EFAULT; \ + typeof(*(ptr)) *__pu_addr = (ptr); \ + typeof(*(ptr)) __pu_val = (typeof(*(ptr)))(x); \ + if (access_ok(VERIFY_WRITE, __pu_addr, size) && __pu_addr) \ + __put_user_size(__pu_val, __pu_addr, (size), __pu_err); \ + __pu_err; \ +}) + +#define __put_user_size(x, ptr, size, retval) \ +do { \ + retval = 0; \ + switch (size) { \ + case 1: \ + __put_user_asm_b(x, ptr, retval); \ + break; \ + case 2: \ + __put_user_asm_h(x, ptr, retval); \ + break; \ + case 4: \ + __put_user_asm_w(x, ptr, retval); \ + break; \ + case 8: \ + __put_user_asm_64(x, ptr, retval); \ + break; \ + default: \ + __put_user_bad(); \ + } \ +} while (0) + +/* + * We don't tell gcc that we are accessing memory, but this is OK + * because we do not write to any memory gcc knows about, so there + * are no aliasing issues. + * + * Note that PC at a fault is the address *after* the faulting + * instruction. + */ +#define __put_user_asm_b(x, ptr, err) \ +do { \ + int errcode; \ + asm volatile( \ + "1: stb %1, (%2,0) \n" \ + " br 3f \n" \ + "2: mov %0, %3 \n" \ + " br 3f \n" \ + ".section __ex_table, \"a\" \n" \ + ".align 2 \n" \ + ".long 1b,2b \n" \ + ".previous \n" \ + "3: \n" \ + : "=r"(err), "=r"(x), "=r"(ptr), "=r"(errcode) \ + : "0"(err), "1"(x), "2"(ptr), "3"(-EFAULT) \ + : "memory"); \ +} while (0) + +#define __put_user_asm_h(x, ptr, err) \ +do { \ + int errcode; \ + asm volatile( \ + "1: sth %1, (%2,0) \n" \ + " br 3f \n" \ + "2: mov %0, %3 \n" \ + " br 3f \n" \ + ".section __ex_table, \"a\" \n" \ + ".align 2 \n" \ + ".long 1b,2b \n" \ + ".previous \n" \ + "3: \n" \ + : "=r"(err), "=r"(x), "=r"(ptr), "=r"(errcode) \ + : "0"(err), "1"(x), "2"(ptr), "3"(-EFAULT) \ + : "memory"); \ +} while (0) + +#define __put_user_asm_w(x, ptr, err) \ +do { \ + int errcode; \ + asm volatile( \ + "1: stw %1, (%2,0) \n" \ + " br 3f \n" \ + "2: mov %0, %3 \n" \ + " br 3f \n" \ + ".section __ex_table,\"a\" \n" \ + ".align 2 \n" \ + ".long 1b, 2b \n" \ + ".previous \n" \ + "3: \n" \ + : "=r"(err), "=r"(x), "=r"(ptr), "=r"(errcode) \ + : "0"(err), "1"(x), "2"(ptr), "3"(-EFAULT) \ + : "memory"); \ +} while (0) + +#define __put_user_asm_64(x, ptr, err) \ +do { \ + int tmp; \ + int errcode; \ + typeof(*(ptr))src = (typeof(*(ptr)))x; \ + typeof(*(ptr))*psrc = &src; \ + \ + asm volatile( \ + " ldw %3, (%1, 0) \n" \ + "1: stw %3, (%2, 0) \n" \ + " ldw %3, (%1, 4) \n" \ + "2: stw %3, (%2, 4) \n" \ + " br 4f \n" \ + "3: mov %0, %4 \n" \ + " br 4f \n" \ + ".section __ex_table, \"a\" \n" \ + ".align 2 \n" \ + ".long 1b, 3b \n" \ + ".long 2b, 3b \n" \ + ".previous \n" \ + "4: \n" \ + : "=r"(err), "=r"(psrc), "=r"(ptr), \ + "=r"(tmp), "=r"(errcode) \ + : "0"(err), "1"(psrc), "2"(ptr), "3"(0), "4"(-EFAULT) \ + : "memory"); \ +} while (0) + +#define __get_user_nocheck(x, ptr, size) \ +({ \ + long __gu_err; \ + __get_user_size(x, (ptr), (size), __gu_err); \ + __gu_err; \ +}) + +#define __get_user_check(x, ptr, size) \ +({ \ + int __gu_err = -EFAULT; \ + const __typeof__(*(ptr)) __user *__gu_ptr = (ptr); \ + if (access_ok(VERIFY_READ, __gu_ptr, size) && __gu_ptr) \ + __get_user_size(x, __gu_ptr, size, __gu_err); \ + __gu_err; \ +}) + +#define __get_user_size(x, ptr, size, retval) \ +do { \ + switch (size) { \ + case 1: \ + __get_user_asm_common((x), ptr, "ldb", retval); \ + break; \ + case 2: \ + __get_user_asm_common((x), ptr, "ldh", retval); \ + break; \ + case 4: \ + __get_user_asm_common((x), ptr, "ldw", retval); \ + break; \ + default: \ + x = 0; \ + (retval) = __get_user_bad(); \ + } \ +} while (0) + +#define __get_user_asm_common(x, ptr, ins, err) \ +do { \ + int errcode; \ + asm volatile( \ + "1: " ins " %1, (%4,0) \n" \ + " br 3f \n" \ + /* Fix up codes */ \ + "2: mov %0, %2 \n" \ + " movi %1, 0 \n" \ + " br 3f \n" \ + ".section __ex_table,\"a\" \n" \ + ".align 2 \n" \ + ".long 1b, 2b \n" \ + ".previous \n" \ + "3: \n" \ + : "=r"(err), "=r"(x), "=r"(errcode) \ + : "0"(0), "r"(ptr), "2"(-EFAULT) \ + : "memory"); \ +} while (0) + +extern int __get_user_bad(void); + +#define __copy_user(to, from, n) \ +do { \ + int w0, w1, w2, w3; \ + asm volatile( \ + "0: cmpnei %1, 0 \n" \ + " bf 8f \n" \ + " mov %3, %1 \n" \ + " or %3, %2 \n" \ + " andi %3, 3 \n" \ + " cmpnei %3, 0 \n" \ + " bf 1f \n" \ + " br 5f \n" \ + "1: cmplti %0, 16 \n" /* 4W */ \ + " bt 3f \n" \ + " ldw %3, (%2, 0) \n" \ + " ldw %4, (%2, 4) \n" \ + " ldw %5, (%2, 8) \n" \ + " ldw %6, (%2, 12) \n" \ + "2: stw %3, (%1, 0) \n" \ + "9: stw %4, (%1, 4) \n" \ + "10: stw %5, (%1, 8) \n" \ + "11: stw %6, (%1, 12) \n" \ + " addi %2, 16 \n" \ + " addi %1, 16 \n" \ + " subi %0, 16 \n" \ + " br 1b \n" \ + "3: cmplti %0, 4 \n" /* 1W */ \ + " bt 5f \n" \ + " ldw %3, (%2, 0) \n" \ + "4: stw %3, (%1, 0) \n" \ + " addi %2, 4 \n" \ + " addi %1, 4 \n" \ + " subi %0, 4 \n" \ + " br 3b \n" \ + "5: cmpnei %0, 0 \n" /* 1B */ \ + " bf 8f \n" \ + " ldb %3, (%2, 0) \n" \ + "6: stb %3, (%1, 0) \n" \ + " addi %2, 1 \n" \ + " addi %1, 1 \n" \ + " subi %0, 1 \n" \ + " br 5b \n" \ + "7: br 8f \n" \ + ".section __ex_table, \"a\" \n" \ + ".align 2 \n" \ + ".long 2b, 7b \n" \ + ".long 9b, 7b \n" \ + ".long 10b, 7b \n" \ + ".long 11b, 7b \n" \ + ".long 4b, 7b \n" \ + ".long 6b, 7b \n" \ + ".previous \n" \ + "8: \n" \ + : "=r"(n), "=r"(to), "=r"(from), "=r"(w0), \ + "=r"(w1), "=r"(w2), "=r"(w3) \ + : "0"(n), "1"(to), "2"(from) \ + : "memory"); \ +} while (0) + +#define __copy_user_zeroing(to, from, n) \ +do { \ + int tmp; \ + int nsave; \ + asm volatile( \ + "0: cmpnei %1, 0 \n" \ + " bf 7f \n" \ + " mov %3, %1 \n" \ + " or %3, %2 \n" \ + " andi %3, 3 \n" \ + " cmpnei %3, 0 \n" \ + " bf 1f \n" \ + " br 5f \n" \ + "1: cmplti %0, 16 \n" \ + " bt 3f \n" \ + "2: ldw %3, (%2, 0) \n" \ + "10: ldw %4, (%2, 4) \n" \ + " stw %3, (%1, 0) \n" \ + " stw %4, (%1, 4) \n" \ + "11: ldw %3, (%2, 8) \n" \ + "12: ldw %4, (%2, 12) \n" \ + " stw %3, (%1, 8) \n" \ + " stw %4, (%1, 12) \n" \ + " addi %2, 16 \n" \ + " addi %1, 16 \n" \ + " subi %0, 16 \n" \ + " br 1b \n" \ + "3: cmplti %0, 4 \n" \ + " bt 5f \n" \ + "4: ldw %3, (%2, 0) \n" \ + " stw %3, (%1, 0) \n" \ + " addi %2, 4 \n" \ + " addi %1, 4 \n" \ + " subi %0, 4 \n" \ + " br 3b \n" \ + "5: cmpnei %0, 0 \n" \ + " bf 7f \n" \ + "6: ldb %3, (%2, 0) \n" \ + " stb %3, (%1, 0) \n" \ + " addi %2, 1 \n" \ + " addi %1, 1 \n" \ + " subi %0, 1 \n" \ + " br 5b \n" \ + "8: mov %3, %0 \n" \ + " movi %4, 0 \n" \ + "9: stb %4, (%1, 0) \n" \ + " addi %1, 1 \n" \ + " subi %3, 1 \n" \ + " cmpnei %3, 0 \n" \ + " bt 9b \n" \ + " br 7f \n" \ + ".section __ex_table, \"a\" \n" \ + ".align 2 \n" \ + ".long 2b, 8b \n" \ + ".long 10b, 8b \n" \ + ".long 11b, 8b \n" \ + ".long 12b, 8b \n" \ + ".long 4b, 8b \n" \ + ".long 6b, 8b \n" \ + ".previous \n" \ + "7: \n" \ + : "=r"(n), "=r"(to), "=r"(from), "=r"(nsave), \ + "=r"(tmp) \ + : "0"(n), "1"(to), "2"(from) \ + : "memory"); \ +} while (0) + +unsigned long raw_copy_from_user(void *to, const void *from, unsigned long n); +unsigned long raw_copy_to_user(void *to, const void *from, unsigned long n); + +unsigned long clear_user(void *to, unsigned long n); +unsigned long __clear_user(void __user *to, unsigned long n); + +long strncpy_from_user(char *dst, const char *src, long count); +long __strncpy_from_user(char *dst, const char *src, long count); + +/* + * Return the size of a string (including the ending 0) + * + * Return 0 on exception, a value greater than N if too long + */ +long strnlen_user(const char *src, long n); + +#define strlen_user(str) strnlen_user(str, 32767) + +struct exception_table_entry { + unsigned long insn; + unsigned long nextinsn; +}; + +extern int fixup_exception(struct pt_regs *regs); + +#endif /* __ASM_CSKY_UACCESS_H */ |