diff options
Diffstat (limited to 'arch/mn10300/include/asm/uaccess.h')
| -rw-r--r-- | arch/mn10300/include/asm/uaccess.h | 495 |
1 files changed, 495 insertions, 0 deletions
diff --git a/arch/mn10300/include/asm/uaccess.h b/arch/mn10300/include/asm/uaccess.h new file mode 100644 index 000000000..537278746 --- /dev/null +++ b/arch/mn10300/include/asm/uaccess.h @@ -0,0 +1,495 @@ +/* MN10300 userspace access functions + * + * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ +#ifndef _ASM_UACCESS_H +#define _ASM_UACCESS_H + +/* + * User space memory access functions + */ +#include <linux/thread_info.h> +#include <linux/kernel.h> +#include <asm/page.h> +#include <asm/errno.h> + +#define VERIFY_READ 0 +#define VERIFY_WRITE 1 + +/* + * 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 MAKE_MM_SEG(s) ((mm_segment_t) { (s) }) + +#define KERNEL_XDS MAKE_MM_SEG(0xBFFFFFFF) +#define KERNEL_DS MAKE_MM_SEG(0x9FFFFFFF) +#define USER_DS MAKE_MM_SEG(TASK_SIZE) + +#define get_ds() (KERNEL_DS) +#define get_fs() (current_thread_info()->addr_limit) +#define set_fs(x) (current_thread_info()->addr_limit = (x)) +#define __kernel_ds_p() (current_thread_info()->addr_limit.seg == 0x9FFFFFFF) + +#define segment_eq(a, b) ((a).seg == (b).seg) + +#define __addr_ok(addr) \ + ((unsigned long)(addr) < (current_thread_info()->addr_limit.seg)) + +/* + * check that a range of addresses falls within the current address limit + */ +static inline int ___range_ok(unsigned long addr, unsigned int size) +{ + int flag = 1, tmp; + + asm(" add %3,%1 \n" /* set C-flag if addr + size > 4Gb */ + " bcs 0f \n" + " cmp %4,%1 \n" /* jump if addr+size>limit (error) */ + " bhi 0f \n" + " clr %0 \n" /* mark okay */ + "0: \n" + : "=r"(flag), "=&r"(tmp) + : "1"(addr), "ir"(size), + "r"(current_thread_info()->addr_limit.seg), "0"(flag) + : "cc" + ); + + return flag; +} + +#define __range_ok(addr, size) ___range_ok((unsigned long)(addr), (u32)(size)) + +#define access_ok(type, addr, size) (__range_ok((addr), (size)) == 0) +#define __access_ok(addr, size) (__range_ok((addr), (size)) == 0) + +static inline int verify_area(int type, const void *addr, unsigned long size) +{ + return access_ok(type, addr, size) ? 0 : -EFAULT; +} + + +/* + * 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; +}; + +/* Returns 0 if exception not found and fixup otherwise. */ +extern int fixup_exception(struct pt_regs *regs); + +#define put_user(x, ptr) __put_user_check((x), (ptr), sizeof(*(ptr))) +#define get_user(x, ptr) __get_user_check((x), (ptr), sizeof(*(ptr))) + +/* + * The "__xxx" versions do not do address space checking, useful when + * doing multiple accesses to the same area (the user has to do the + * checks by hand with "access_ok()") + */ +#define __put_user(x, ptr) __put_user_nocheck((x), (ptr), sizeof(*(ptr))) +#define __get_user(x, ptr) __get_user_nocheck((x), (ptr), sizeof(*(ptr))) + +/* + * The "xxx_ret" versions return constant specified in third argument, if + * something bad happens. These macros can be optimized for the + * case of just returning from the function xxx_ret is used. + */ + +#define put_user_ret(x, ptr, ret) \ + ({ if (put_user((x), (ptr))) return (ret); }) +#define get_user_ret(x, ptr, ret) \ + ({ if (get_user((x), (ptr))) return (ret); }) +#define __put_user_ret(x, ptr, ret) \ + ({ if (__put_user((x), (ptr))) return (ret); }) +#define __get_user_ret(x, ptr, ret) \ + ({ if (__get_user((x), (ptr))) return (ret); }) + +struct __large_struct { unsigned long buf[100]; }; +#define __m(x) (*(struct __large_struct *)(x)) + +#define __get_user_nocheck(x, ptr, size) \ +({ \ + unsigned long __gu_addr; \ + int __gu_err; \ + __gu_addr = (unsigned long) (ptr); \ + switch (size) { \ + case 1: { \ + unsigned char __gu_val; \ + __get_user_asm("bu"); \ + (x) = *(__force __typeof__(*(ptr))*) &__gu_val; \ + break; \ + } \ + case 2: { \ + unsigned short __gu_val; \ + __get_user_asm("hu"); \ + (x) = *(__force __typeof__(*(ptr))*) &__gu_val; \ + break; \ + } \ + case 4: { \ + unsigned int __gu_val; \ + __get_user_asm(""); \ + (x) = *(__force __typeof__(*(ptr))*) &__gu_val; \ + break; \ + } \ + default: \ + __get_user_unknown(); \ + break; \ + } \ + __gu_err; \ +}) + +#define __get_user_check(x, ptr, size) \ +({ \ + const __typeof__(*(ptr))* __guc_ptr = (ptr); \ + int _e; \ + if (likely(__access_ok((unsigned long) __guc_ptr, (size)))) \ + _e = __get_user_nocheck((x), __guc_ptr, (size)); \ + else { \ + _e = -EFAULT; \ + (x) = (__typeof__(x))0; \ + } \ + _e; \ +}) + +#define __get_user_asm(INSN) \ +({ \ + asm volatile( \ + "1:\n" \ + " mov"INSN" %2,%1\n" \ + " mov 0,%0\n" \ + "2:\n" \ + " .section .fixup,\"ax\"\n" \ + "3:\n\t" \ + " mov %3,%0\n" \ + " jmp 2b\n" \ + " .previous\n" \ + " .section __ex_table,\"a\"\n" \ + " .balign 4\n" \ + " .long 1b, 3b\n" \ + " .previous" \ + : "=&r" (__gu_err), "=&r" (__gu_val) \ + : "m" (__m(__gu_addr)), "i" (-EFAULT)); \ +}) + +extern int __get_user_unknown(void); + +#define __put_user_nocheck(x, ptr, size) \ +({ \ + union { \ + __typeof__(*(ptr)) val; \ + u32 bits[2]; \ + } __pu_val; \ + unsigned long __pu_addr; \ + int __pu_err; \ + __pu_val.val = (x); \ + __pu_addr = (unsigned long) (ptr); \ + switch (size) { \ + case 1: __put_user_asm("bu"); break; \ + case 2: __put_user_asm("hu"); break; \ + case 4: __put_user_asm("" ); break; \ + case 8: __put_user_asm8(); break; \ + default: __pu_err = __put_user_unknown(); break; \ + } \ + __pu_err; \ +}) + +#define __put_user_check(x, ptr, size) \ +({ \ + union { \ + __typeof__(*(ptr)) val; \ + u32 bits[2]; \ + } __pu_val; \ + unsigned long __pu_addr; \ + int __pu_err; \ + __pu_val.val = (x); \ + __pu_addr = (unsigned long) (ptr); \ + if (likely(__access_ok(__pu_addr, size))) { \ + switch (size) { \ + case 1: __put_user_asm("bu"); break; \ + case 2: __put_user_asm("hu"); break; \ + case 4: __put_user_asm("" ); break; \ + case 8: __put_user_asm8(); break; \ + default: __pu_err = __put_user_unknown(); break; \ + } \ + } \ + else { \ + __pu_err = -EFAULT; \ + } \ + __pu_err; \ +}) + +#define __put_user_asm(INSN) \ +({ \ + asm volatile( \ + "1:\n" \ + " mov"INSN" %1,%2\n" \ + " mov 0,%0\n" \ + "2:\n" \ + " .section .fixup,\"ax\"\n" \ + "3:\n" \ + " mov %3,%0\n" \ + " jmp 2b\n" \ + " .previous\n" \ + " .section __ex_table,\"a\"\n" \ + " .balign 4\n" \ + " .long 1b, 3b\n" \ + " .previous" \ + : "=&r" (__pu_err) \ + : "r" (__pu_val.val), "m" (__m(__pu_addr)), \ + "i" (-EFAULT) \ + ); \ +}) + +#define __put_user_asm8() \ +({ \ + asm volatile( \ + "1: mov %1,%3 \n" \ + "2: mov %2,%4 \n" \ + " mov 0,%0 \n" \ + "3: \n" \ + " .section .fixup,\"ax\" \n" \ + "4: \n" \ + " mov %5,%0 \n" \ + " jmp 3b \n" \ + " .previous \n" \ + " .section __ex_table,\"a\"\n" \ + " .balign 4 \n" \ + " .long 1b, 4b \n" \ + " .long 2b, 4b \n" \ + " .previous \n" \ + : "=&r" (__pu_err) \ + : "r" (__pu_val.bits[0]), "r" (__pu_val.bits[1]), \ + "m" (__m(__pu_addr)), "m" (__m(__pu_addr+4)), \ + "i" (-EFAULT) \ + ); \ +}) + +extern int __put_user_unknown(void); + + +/* + * Copy To/From Userspace + */ +/* Generic arbitrary sized copy. */ +#define __copy_user(to, from, size) \ +do { \ + if (size) { \ + void *__to = to; \ + const void *__from = from; \ + int w; \ + asm volatile( \ + "0: movbu (%0),%3;\n" \ + "1: movbu %3,(%1);\n" \ + " inc %0;\n" \ + " inc %1;\n" \ + " add -1,%2;\n" \ + " bne 0b;\n" \ + "2:\n" \ + " .section .fixup,\"ax\"\n" \ + "3: jmp 2b\n" \ + " .previous\n" \ + " .section __ex_table,\"a\"\n" \ + " .balign 4\n" \ + " .long 0b,3b\n" \ + " .long 1b,3b\n" \ + " .previous\n" \ + : "=a"(__from), "=a"(__to), "=r"(size), "=&r"(w)\ + : "0"(__from), "1"(__to), "2"(size) \ + : "cc", "memory"); \ + } \ +} while (0) + +#define __copy_user_zeroing(to, from, size) \ +do { \ + if (size) { \ + void *__to = to; \ + const void *__from = from; \ + int w; \ + asm volatile( \ + "0: movbu (%0),%3;\n" \ + "1: movbu %3,(%1);\n" \ + " inc %0;\n" \ + " inc %1;\n" \ + " add -1,%2;\n" \ + " bne 0b;\n" \ + "2:\n" \ + " .section .fixup,\"ax\"\n" \ + "3:\n" \ + " mov %2,%0\n" \ + " clr %3\n" \ + "4: movbu %3,(%1);\n" \ + " inc %1;\n" \ + " add -1,%2;\n" \ + " bne 4b;\n" \ + " mov %0,%2\n" \ + " jmp 2b\n" \ + " .previous\n" \ + " .section __ex_table,\"a\"\n" \ + " .balign 4\n" \ + " .long 0b,3b\n" \ + " .long 1b,3b\n" \ + " .previous\n" \ + : "=a"(__from), "=a"(__to), "=r"(size), "=&r"(w)\ + : "0"(__from), "1"(__to), "2"(size) \ + : "cc", "memory"); \ + } \ +} while (0) + +/* We let the __ versions of copy_from/to_user inline, because they're often + * used in fast paths and have only a small space overhead. + */ +static inline +unsigned long __generic_copy_from_user_nocheck(void *to, const void *from, + unsigned long n) +{ + __copy_user_zeroing(to, from, n); + return n; +} + +static inline +unsigned long __generic_copy_to_user_nocheck(void *to, const void *from, + unsigned long n) +{ + __copy_user(to, from, n); + return n; +} + + +#if 0 +#error "don't use - these macros don't increment to & from pointers" +/* Optimize just a little bit when we know the size of the move. */ +#define __constant_copy_user(to, from, size) \ +do { \ + asm volatile( \ + " mov %0,a0;\n" \ + "0: movbu (%1),d3;\n" \ + "1: movbu d3,(%2);\n" \ + " add -1,a0;\n" \ + " bne 0b;\n" \ + "2:;" \ + ".section .fixup,\"ax\"\n" \ + "3: jmp 2b\n" \ + ".previous\n" \ + ".section __ex_table,\"a\"\n" \ + " .balign 4\n" \ + " .long 0b,3b\n" \ + " .long 1b,3b\n" \ + ".previous" \ + : \ + : "d"(size), "d"(to), "d"(from) \ + : "d3", "a0"); \ +} while (0) + +/* Optimize just a little bit when we know the size of the move. */ +#define __constant_copy_user_zeroing(to, from, size) \ +do { \ + asm volatile( \ + " mov %0,a0;\n" \ + "0: movbu (%1),d3;\n" \ + "1: movbu d3,(%2);\n" \ + " add -1,a0;\n" \ + " bne 0b;\n" \ + "2:;" \ + ".section .fixup,\"ax\"\n" \ + "3: jmp 2b\n" \ + ".previous\n" \ + ".section __ex_table,\"a\"\n" \ + " .balign 4\n" \ + " .long 0b,3b\n" \ + " .long 1b,3b\n" \ + ".previous" \ + : \ + : "d"(size), "d"(to), "d"(from) \ + : "d3", "a0"); \ +} while (0) + +static inline +unsigned long __constant_copy_to_user(void *to, const void *from, + unsigned long n) +{ + if (access_ok(VERIFY_WRITE, to, n)) + __constant_copy_user(to, from, n); + return n; +} + +static inline +unsigned long __constant_copy_from_user(void *to, const void *from, + unsigned long n) +{ + if (access_ok(VERIFY_READ, from, n)) + __constant_copy_user_zeroing(to, from, n); + return n; +} + +static inline +unsigned long __constant_copy_to_user_nocheck(void *to, const void *from, + unsigned long n) +{ + __constant_copy_user(to, from, n); + return n; +} + +static inline +unsigned long __constant_copy_from_user_nocheck(void *to, const void *from, + unsigned long n) +{ + __constant_copy_user_zeroing(to, from, n); + return n; +} +#endif + +extern unsigned long __generic_copy_to_user(void __user *, const void *, + unsigned long); +extern unsigned long __generic_copy_from_user(void *, const void __user *, + unsigned long); + +#define __copy_to_user_inatomic(to, from, n) \ + __generic_copy_to_user_nocheck((to), (from), (n)) +#define __copy_from_user_inatomic(to, from, n) \ + __generic_copy_from_user_nocheck((to), (from), (n)) + +#define __copy_to_user(to, from, n) \ +({ \ + might_fault(); \ + __copy_to_user_inatomic((to), (from), (n)); \ +}) + +#define __copy_from_user(to, from, n) \ +({ \ + might_fault(); \ + __copy_from_user_inatomic((to), (from), (n)); \ +}) + + +#define copy_to_user(to, from, n) __generic_copy_to_user((to), (from), (n)) +#define copy_from_user(to, from, n) __generic_copy_from_user((to), (from), (n)) + +extern long strncpy_from_user(char *dst, const char __user *src, long count); +extern long __strncpy_from_user(char *dst, const char __user *src, long count); +extern long strnlen_user(const char __user *str, long n); +#define strlen_user(str) strnlen_user(str, ~0UL >> 1) +extern unsigned long clear_user(void __user *mem, unsigned long len); +extern unsigned long __clear_user(void __user *mem, unsigned long len); + +#endif /* _ASM_UACCESS_H */ |