diff options
Diffstat (limited to 'include/asm-sh/uaccess.h')
| -rw-r--r-- | include/asm-sh/uaccess.h | 222 |
1 files changed, 222 insertions, 0 deletions
diff --git a/include/asm-sh/uaccess.h b/include/asm-sh/uaccess.h index b3440c305b5..45c2c9b2993 100644 --- a/include/asm-sh/uaccess.h +++ b/include/asm-sh/uaccess.h @@ -1,12 +1,171 @@ #ifndef __ASM_SH_UACCESS_H #define __ASM_SH_UACCESS_H +#include <linux/errno.h> +#include <linux/sched.h> +#include <asm/segment.h> + +#define VERIFY_READ 0 +#define VERIFY_WRITE 1 + +#define __addr_ok(addr) \ + ((unsigned long __force)(addr) < current_thread_info()->addr_limit.seg) + +/* + * __access_ok: Check if address with size is OK or not. + * + * Uhhuh, this needs 33-bit arithmetic. We have a carry.. + * + * sum := addr + size; carry? --> flag = true; + * if (sum >= addr_limit) flag = true; + */ +#define __access_ok(addr, size) \ + (__addr_ok((addr) + (size))) +#define access_ok(type, addr, size) \ + (__chk_user_ptr(addr), \ + __access_ok((unsigned long __force)(addr), (size))) + +/* + * Uh, these should become the main single-value transfer routines ... + * They automatically use the right size if we just have the right + * pointer type ... + * + * As SuperH uses the same address space for kernel and user data, we + * can just do these as direct assignments. + * + * Careful to not + * (a) re-use the arguments for side effects (sizeof is ok) + * (b) require any knowledge of processes at this stage + */ +#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))) + +struct __large_struct { unsigned long buf[100]; }; +#define __m(x) (*(struct __large_struct __user *)(x)) + +#define __get_user_nocheck(x,ptr,size) \ +({ \ + long __gu_err; \ + unsigned long __gu_val; \ + const __typeof__(*(ptr)) __user *__gu_addr = (ptr); \ + __chk_user_ptr(ptr); \ + __get_user_size(__gu_val, __gu_addr, (size), __gu_err); \ + (x) = (__typeof__(*(ptr)))__gu_val; \ + __gu_err; \ +}) + +#define __get_user_check(x,ptr,size) \ +({ \ + long __gu_err = -EFAULT; \ + unsigned long __gu_val = 0; \ + const __typeof__(*(ptr)) *__gu_addr = (ptr); \ + if (likely(access_ok(VERIFY_READ, __gu_addr, (size)))) \ + __get_user_size(__gu_val, __gu_addr, (size), __gu_err); \ + (x) = (__typeof__(*(ptr)))__gu_val; \ + __gu_err; \ +}) + +#define __put_user_nocheck(x,ptr,size) \ +({ \ + long __pu_err; \ + __typeof__(*(ptr)) __user *__pu_addr = (ptr); \ + __chk_user_ptr(ptr); \ + __put_user_size((x), __pu_addr, (size), __pu_err); \ + __pu_err; \ +}) + +#define __put_user_check(x,ptr,size) \ +({ \ + long __pu_err = -EFAULT; \ + __typeof__(*(ptr)) __user *__pu_addr = (ptr); \ + if (likely(access_ok(VERIFY_WRITE, __pu_addr, size))) \ + __put_user_size((x), __pu_addr, (size), \ + __pu_err); \ + __pu_err; \ +}) + #ifdef CONFIG_SUPERH32 # include "uaccess_32.h" #else # include "uaccess_64.h" #endif +/* Generic arbitrary sized copy. */ +/* Return the number of bytes NOT copied */ +__kernel_size_t __copy_user(void *to, const void *from, __kernel_size_t n); + +static __always_inline unsigned long +__copy_from_user(void *to, const void __user *from, unsigned long n) +{ + return __copy_user(to, (__force void *)from, n); +} + +static __always_inline unsigned long __must_check +__copy_to_user(void __user *to, const void *from, unsigned long n) +{ + return __copy_user((__force void *)to, from, n); +} + +#define __copy_to_user_inatomic __copy_to_user +#define __copy_from_user_inatomic __copy_from_user + +/* + * Clear the area and return remaining number of bytes + * (on failure. Usually it's 0.) + */ +__kernel_size_t __clear_user(void *addr, __kernel_size_t size); + +#define clear_user(addr,n) \ +({ \ + void __user * __cl_addr = (addr); \ + unsigned long __cl_size = (n); \ + \ + if (__cl_size && access_ok(VERIFY_WRITE, \ + ((unsigned long)(__cl_addr)), __cl_size)) \ + __cl_size = __clear_user(__cl_addr, __cl_size); \ + \ + __cl_size; \ +}) + +/** + * strncpy_from_user: - Copy a NUL terminated string from userspace. + * @dst: Destination address, in kernel space. This buffer must be at + * least @count bytes long. + * @src: Source address, in user space. + * @count: Maximum number of bytes to copy, including the trailing NUL. + * + * Copies a NUL-terminated string from userspace to kernel space. + * + * On success, returns the length of the string (not including the trailing + * NUL). + * + * If access to userspace fails, returns -EFAULT (some data may have been + * copied). + * + * If @count is smaller than the length of the string, copies @count bytes + * and returns @count. + */ +#define strncpy_from_user(dest,src,count) \ +({ \ + unsigned long __sfu_src = (unsigned long)(src); \ + int __sfu_count = (int)(count); \ + long __sfu_res = -EFAULT; \ + \ + if (__access_ok(__sfu_src, __sfu_count)) \ + __sfu_res = __strncpy_from_user((unsigned long)(dest), \ + __sfu_src, __sfu_count); \ + \ + __sfu_res; \ +}) + static inline unsigned long copy_from_user(void *to, const void __user *from, unsigned long n) { @@ -31,4 +190,67 @@ copy_to_user(void __user *to, const void *from, unsigned long n) return __copy_size; } +/** + * strnlen_user: - Get the size of a string in user space. + * @s: The string to measure. + * @n: The maximum valid length + * + * Context: User context only. This function may sleep. + * + * Get the size of a NUL-terminated string in user space. + * + * Returns the size of the string INCLUDING the terminating NUL. + * On exception, returns 0. + * If the string is too long, returns a value greater than @n. + */ +static inline long strnlen_user(const char __user *s, long n) +{ + if (!__addr_ok(s)) + return 0; + else + return __strnlen_user(s, n); +} + +/** + * strlen_user: - Get the size of a string in user space. + * @str: The string to measure. + * + * Context: User context only. This function may sleep. + * + * Get the size of a NUL-terminated string in user space. + * + * Returns the size of the string INCLUDING the terminating NUL. + * On exception, returns 0. + * + * If there is a limit on the length of a valid string, you may wish to + * consider using strnlen_user() instead. + */ +#define strlen_user(str) strnlen_user(str, ~0UL >> 1) + +/* + * 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; +}; + +#if defined(CONFIG_SUPERH64) && defined(CONFIG_MMU) +#define ARCH_HAS_SEARCH_EXTABLE +#endif + +int fixup_exception(struct pt_regs *regs); +/* Returns 0 if exception not found and fixup.unit otherwise. */ +unsigned long search_exception_table(unsigned long addr); +const struct exception_table_entry *search_exception_tables(unsigned long addr); + + #endif /* __ASM_SH_UACCESS_H */ |