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Diffstat (limited to 'arch/cris/include/asm/uaccess.h')
| -rw-r--r-- | arch/cris/include/asm/uaccess.h | 404 |
1 files changed, 404 insertions, 0 deletions
diff --git a/arch/cris/include/asm/uaccess.h b/arch/cris/include/asm/uaccess.h new file mode 100644 index 000000000000..914540801c5e --- /dev/null +++ b/arch/cris/include/asm/uaccess.h @@ -0,0 +1,404 @@ +/* + * Authors: Bjorn Wesen (bjornw@axis.com) + * Hans-Peter Nilsson (hp@axis.com) + */ + +/* Asm:s have been tweaked (within the domain of correctness) to give + satisfactory results for "gcc version 2.96 20000427 (experimental)". + + Check regularly... + + Register $r9 is chosen for temporaries, being a call-clobbered register + first in line to be used (notably for local blocks), not colliding with + parameter registers. */ + +#ifndef _CRIS_UACCESS_H +#define _CRIS_UACCESS_H + +#ifndef __ASSEMBLY__ +#include <linux/sched.h> +#include <linux/errno.h> +#include <asm/processor.h> +#include <asm/page.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) }) + +/* addr_limit is the maximum accessible address for the task. we misuse + * the KERNEL_DS and USER_DS values to both assign and compare the + * addr_limit values through the equally misnamed get/set_fs macros. + * (see above) + */ + +#define KERNEL_DS MAKE_MM_SEG(0xFFFFFFFF) +#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 segment_eq(a,b) ((a).seg == (b).seg) + +#define __kernel_ok (segment_eq(get_fs(), KERNEL_DS)) +#define __user_ok(addr,size) (((size) <= TASK_SIZE)&&((addr) <= TASK_SIZE-(size))) +#define __access_ok(addr,size) (__kernel_ok || __user_ok((addr),(size))) +#define access_ok(type,addr,size) __access_ok((unsigned long)(addr),(size)) + +#include <arch/uaccess.h> + +/* + * 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; +}; + +/* + * 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 + * CRIS, we can just do these as direct assignments. (Of course, the + * exception handling means that it's no longer "just"...) + */ +#define get_user(x,ptr) \ + __get_user_check((x),(ptr),sizeof(*(ptr))) +#define put_user(x,ptr) \ + __put_user_check((__typeof__(*(ptr)))(x),(ptr),sizeof(*(ptr))) + +#define __get_user(x,ptr) \ + __get_user_nocheck((x),(ptr),sizeof(*(ptr))) +#define __put_user(x,ptr) \ + __put_user_nocheck((__typeof__(*(ptr)))(x),(ptr),sizeof(*(ptr))) + +extern long __put_user_bad(void); + +#define __put_user_size(x,ptr,size,retval) \ +do { \ + retval = 0; \ + switch (size) { \ + case 1: __put_user_asm(x,ptr,retval,"move.b"); break; \ + case 2: __put_user_asm(x,ptr,retval,"move.w"); break; \ + case 4: __put_user_asm(x,ptr,retval,"move.d"); break; \ + case 8: __put_user_asm_64(x,ptr,retval); break; \ + default: __put_user_bad(); \ + } \ +} while (0) + +#define __get_user_size(x,ptr,size,retval) \ +do { \ + retval = 0; \ + switch (size) { \ + case 1: __get_user_asm(x,ptr,retval,"move.b"); break; \ + case 2: __get_user_asm(x,ptr,retval,"move.w"); break; \ + case 4: __get_user_asm(x,ptr,retval,"move.d"); break; \ + case 8: __get_user_asm_64(x,ptr,retval); break; \ + default: (x) = __get_user_bad(); \ + } \ +} while (0) + +#define __put_user_nocheck(x,ptr,size) \ +({ \ + long __pu_err; \ + __put_user_size((x),(ptr),(size),__pu_err); \ + __pu_err; \ +}) + +#define __put_user_check(x,ptr,size) \ +({ \ + long __pu_err = -EFAULT; \ + __typeof__(*(ptr)) *__pu_addr = (ptr); \ + if (access_ok(VERIFY_WRITE,__pu_addr,size)) \ + __put_user_size((x),__pu_addr,(size),__pu_err); \ + __pu_err; \ +}) + +struct __large_struct { unsigned long buf[100]; }; +#define __m(x) (*(struct __large_struct *)(x)) + + + +#define __get_user_nocheck(x,ptr,size) \ +({ \ + long __gu_err, __gu_val; \ + __get_user_size(__gu_val,(ptr),(size),__gu_err); \ + (x) = (__typeof__(*(ptr)))__gu_val; \ + __gu_err; \ +}) + +#define __get_user_check(x,ptr,size) \ +({ \ + long __gu_err = -EFAULT, __gu_val = 0; \ + const __typeof__(*(ptr)) *__gu_addr = (ptr); \ + if (access_ok(VERIFY_READ,__gu_addr,size)) \ + __get_user_size(__gu_val,__gu_addr,(size),__gu_err); \ + (x) = (__typeof__(*(ptr)))__gu_val; \ + __gu_err; \ +}) + +extern long __get_user_bad(void); + +/* More complex functions. Most are inline, but some call functions that + live in lib/usercopy.c */ + +extern unsigned long __copy_user(void __user *to, const void *from, unsigned long n); +extern unsigned long __copy_user_zeroing(void *to, const void __user *from, unsigned long n); +extern unsigned long __do_clear_user(void __user *to, unsigned long n); + +static inline unsigned long +__generic_copy_to_user(void __user *to, const void *from, unsigned long n) +{ + if (access_ok(VERIFY_WRITE, to, n)) + return __copy_user(to,from,n); + return n; +} + +static inline unsigned long +__generic_copy_from_user(void *to, const void __user *from, unsigned long n) +{ + if (access_ok(VERIFY_READ, from, n)) + return __copy_user_zeroing(to,from,n); + return n; +} + +static inline unsigned long +__generic_clear_user(void __user *to, unsigned long n) +{ + if (access_ok(VERIFY_WRITE, to, n)) + return __do_clear_user(to,n); + return n; +} + +static inline long +__strncpy_from_user(char *dst, const char __user *src, long count) +{ + return __do_strncpy_from_user(dst, src, count); +} + +static inline long +strncpy_from_user(char *dst, const char __user *src, long count) +{ + long res = -EFAULT; + if (access_ok(VERIFY_READ, src, 1)) + res = __do_strncpy_from_user(dst, src, count); + return res; +} + + +/* Note that these expand awfully if made into switch constructs, so + don't do that. */ + +static inline unsigned long +__constant_copy_from_user(void *to, const void __user *from, unsigned long n) +{ + unsigned long ret = 0; + if (n == 0) + ; + else if (n == 1) + __asm_copy_from_user_1(to, from, ret); + else if (n == 2) + __asm_copy_from_user_2(to, from, ret); + else if (n == 3) + __asm_copy_from_user_3(to, from, ret); + else if (n == 4) + __asm_copy_from_user_4(to, from, ret); + else if (n == 5) + __asm_copy_from_user_5(to, from, ret); + else if (n == 6) + __asm_copy_from_user_6(to, from, ret); + else if (n == 7) + __asm_copy_from_user_7(to, from, ret); + else if (n == 8) + __asm_copy_from_user_8(to, from, ret); + else if (n == 9) + __asm_copy_from_user_9(to, from, ret); + else if (n == 10) + __asm_copy_from_user_10(to, from, ret); + else if (n == 11) + __asm_copy_from_user_11(to, from, ret); + else if (n == 12) + __asm_copy_from_user_12(to, from, ret); + else if (n == 13) + __asm_copy_from_user_13(to, from, ret); + else if (n == 14) + __asm_copy_from_user_14(to, from, ret); + else if (n == 15) + __asm_copy_from_user_15(to, from, ret); + else if (n == 16) + __asm_copy_from_user_16(to, from, ret); + else if (n == 20) + __asm_copy_from_user_20(to, from, ret); + else if (n == 24) + __asm_copy_from_user_24(to, from, ret); + else + ret = __generic_copy_from_user(to, from, n); + + return ret; +} + +/* Ditto, don't make a switch out of this. */ + +static inline unsigned long +__constant_copy_to_user(void __user *to, const void *from, unsigned long n) +{ + unsigned long ret = 0; + if (n == 0) + ; + else if (n == 1) + __asm_copy_to_user_1(to, from, ret); + else if (n == 2) + __asm_copy_to_user_2(to, from, ret); + else if (n == 3) + __asm_copy_to_user_3(to, from, ret); + else if (n == 4) + __asm_copy_to_user_4(to, from, ret); + else if (n == 5) + __asm_copy_to_user_5(to, from, ret); + else if (n == 6) + __asm_copy_to_user_6(to, from, ret); + else if (n == 7) + __asm_copy_to_user_7(to, from, ret); + else if (n == 8) + __asm_copy_to_user_8(to, from, ret); + else if (n == 9) + __asm_copy_to_user_9(to, from, ret); + else if (n == 10) + __asm_copy_to_user_10(to, from, ret); + else if (n == 11) + __asm_copy_to_user_11(to, from, ret); + else if (n == 12) + __asm_copy_to_user_12(to, from, ret); + else if (n == 13) + __asm_copy_to_user_13(to, from, ret); + else if (n == 14) + __asm_copy_to_user_14(to, from, ret); + else if (n == 15) + __asm_copy_to_user_15(to, from, ret); + else if (n == 16) + __asm_copy_to_user_16(to, from, ret); + else if (n == 20) + __asm_copy_to_user_20(to, from, ret); + else if (n == 24) + __asm_copy_to_user_24(to, from, ret); + else + ret = __generic_copy_to_user(to, from, n); + + return ret; +} + +/* No switch, please. */ + +static inline unsigned long +__constant_clear_user(void __user *to, unsigned long n) +{ + unsigned long ret = 0; + if (n == 0) + ; + else if (n == 1) + __asm_clear_1(to, ret); + else if (n == 2) + __asm_clear_2(to, ret); + else if (n == 3) + __asm_clear_3(to, ret); + else if (n == 4) + __asm_clear_4(to, ret); + else if (n == 8) + __asm_clear_8(to, ret); + else if (n == 12) + __asm_clear_12(to, ret); + else if (n == 16) + __asm_clear_16(to, ret); + else if (n == 20) + __asm_clear_20(to, ret); + else if (n == 24) + __asm_clear_24(to, ret); + else + ret = __generic_clear_user(to, n); + + return ret; +} + + +#define clear_user(to, n) \ +(__builtin_constant_p(n) ? \ + __constant_clear_user(to, n) : \ + __generic_clear_user(to, n)) + +#define copy_from_user(to, from, n) \ +(__builtin_constant_p(n) ? \ + __constant_copy_from_user(to, from, n) : \ + __generic_copy_from_user(to, from, n)) + +#define copy_to_user(to, from, n) \ +(__builtin_constant_p(n) ? \ + __constant_copy_to_user(to, from, n) : \ + __generic_copy_to_user(to, from, n)) + +/* 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 __user *from, + unsigned long n) +{ + return __copy_user_zeroing(to,from,n); +} + +static inline unsigned long +__generic_copy_to_user_nocheck(void __user *to, const void *from, + unsigned long n) +{ + return __copy_user(to,from,n); +} + +static inline unsigned long +__generic_clear_user_nocheck(void __user *to, unsigned long n) +{ + return __do_clear_user(to,n); +} + +/* without checking */ + +#define __copy_to_user(to,from,n) __generic_copy_to_user_nocheck((to),(from),(n)) +#define __copy_from_user(to,from,n) __generic_copy_from_user_nocheck((to),(from),(n)) +#define __copy_to_user_inatomic __copy_to_user +#define __copy_from_user_inatomic __copy_from_user +#define __clear_user(to,n) __generic_clear_user_nocheck((to),(n)) + +#define strlen_user(str) strnlen_user((str), 0x7ffffffe) + +#endif /* __ASSEMBLY__ */ + +#endif /* _CRIS_UACCESS_H */ |