uaccess.h

来自「Linux Kernel 2.6.9 for OMAP1710」· C头文件 代码 · 共 826 行 · 第 1/2 页

#else
#define __MODULE_JAL(destination)					\
	"jal\t" #destination "\n\t"
#endif

extern size_t __copy_user(void *__to, const void *__from, size_t __n);

#define __invoke_copy_to_user(to,from,n)				\
({									\
	register void *__cu_to_r __asm__ ("$4");			\
	register const void *__cu_from_r __asm__ ("$5");		\
	register long __cu_len_r __asm__ ("$6");			\
									\
	__cu_to_r = (to);						\
	__cu_from_r = (from);						\
	__cu_len_r = (n);						\
	__asm__ __volatile__(						\
	__MODULE_JAL(__copy_user)					\
	: "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r)	\
	:								\
	: "$8", "$9", "$10", "$11", "$12", "$15", "$24", "$31",		\
	  "memory");							\
	__cu_len_r;							\
})

/*
 * __copy_to_user: - Copy a block of data into user space, with less checking.
 * @to:   Destination address, in user space.
 * @from: Source address, in kernel space.
 * @n:    Number of bytes to copy.
 *
 * Context: User context only.  This function may sleep.
 *
 * Copy data from kernel space to user space.  Caller must check
 * the specified block with access_ok() before calling this function.
 *
 * Returns number of bytes that could not be copied.
 * On success, this will be zero.
 */
#define __copy_to_user(to,from,n)					\
({									\
	void *__cu_to;							\
	const void *__cu_from;						\
	long __cu_len;							\
									\
	might_sleep();							\
	__cu_to = (to);							\
	__cu_from = (from);						\
	__cu_len = (n);							\
	__cu_len = __invoke_copy_to_user(__cu_to, __cu_from, __cu_len);	\
	__cu_len;							\
})

#define __copy_to_user_inatomic __copy_to_user
#define __copy_from_user_inatomic __copy_from_user

/*
 * copy_to_user: - Copy a block of data into user space.
 * @to:   Destination address, in user space.
 * @from: Source address, in kernel space.
 * @n:    Number of bytes to copy.
 *
 * Context: User context only.  This function may sleep.
 *
 * Copy data from kernel space to user space.
 *
 * Returns number of bytes that could not be copied.
 * On success, this will be zero.
 */
#define copy_to_user(to,from,n)						\
({									\
	void *__cu_to;							\
	const void *__cu_from;						\
	long __cu_len;							\
									\
	might_sleep();							\
	__cu_to = (to);							\
	__cu_from = (from);						\
	__cu_len = (n);							\
	if (access_ok(VERIFY_WRITE, __cu_to, __cu_len))			\
		__cu_len = __invoke_copy_to_user(__cu_to, __cu_from,	\
		                                 __cu_len);		\
	__cu_len;							\
})

#define __invoke_copy_from_user(to,from,n)				\
({									\
	register void *__cu_to_r __asm__ ("$4");			\
	register const void *__cu_from_r __asm__ ("$5");		\
	register long __cu_len_r __asm__ ("$6");			\
									\
	__cu_to_r = (to);						\
	__cu_from_r = (from);						\
	__cu_len_r = (n);						\
	__asm__ __volatile__(						\
	".set\tnoreorder\n\t"						\
	__MODULE_JAL(__copy_user)					\
	".set\tnoat\n\t"						\
	__UA_ADDU "\t$1, %1, %2\n\t"					\
	".set\tat\n\t"							\
	".set\treorder\n\t"						\
	"move\t%0, $6"		/* XXX */				\
	: "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r)	\
	:								\
	: "$8", "$9", "$10", "$11", "$12", "$15", "$24", "$31",		\
	  "memory");							\
	__cu_len_r;							\
})

/*
 * __copy_from_user: - Copy a block of data from user space, with less checking. * @to:   Destination address, in kernel space.
 * @from: Source address, in user space.
 * @n:    Number of bytes to copy.
 *
 * Context: User context only.  This function may sleep.
 *
 * Copy data from user space to kernel space.  Caller must check
 * the specified block with access_ok() before calling this function.
 *
 * Returns number of bytes that could not be copied.
 * On success, this will be zero.
 *
 * If some data could not be copied, this function will pad the copied
 * data to the requested size using zero bytes.
 */
#define __copy_from_user(to,from,n)					\
({									\
	void *__cu_to;							\
	const void *__cu_from;						\
	long __cu_len;							\
									\
	might_sleep();							\
	__cu_to = (to);							\
	__cu_from = (from);						\
	__cu_len = (n);							\
	__cu_len = __invoke_copy_from_user(__cu_to, __cu_from,		\
	                                   __cu_len);			\
	__cu_len;							\
})

/*
 * copy_from_user: - Copy a block of data from user space.
 * @to:   Destination address, in kernel space.
 * @from: Source address, in user space.
 * @n:    Number of bytes to copy.
 *
 * Context: User context only.  This function may sleep.
 *
 * Copy data from user space to kernel space.
 *
 * Returns number of bytes that could not be copied.
 * On success, this will be zero.
 *
 * If some data could not be copied, this function will pad the copied
 * data to the requested size using zero bytes.
 */
#define copy_from_user(to,from,n)					\
({									\
	void *__cu_to;							\
	const void *__cu_from;						\
	long __cu_len;							\
									\
	might_sleep();							\
	__cu_to = (to);							\
	__cu_from = (from);						\
	__cu_len = (n);							\
	if (access_ok(VERIFY_READ, __cu_from, __cu_len))		\
		__cu_len = __invoke_copy_from_user(__cu_to, __cu_from,	\
		                                   __cu_len);		\
	__cu_len;							\
})

#define __copy_in_user(to, from, n)	__copy_from_user(to, from, n)

#define copy_in_user(to,from,n)						\
({									\
	void *__cu_to;							\
	const void *__cu_from;						\
	long __cu_len;							\
									\
	might_sleep();							\
	__cu_to = (to);							\
	__cu_from = (from);						\
	__cu_len = (n);							\
	if (likely(access_ok(VERIFY_READ, __cu_from, __cu_len) &&	\
	           access_ok(VERIFY_WRITE, __cu_to, __cu_len)))		\
		__cu_len = __invoke_copy_from_user(__cu_to, __cu_from,	\
		                                   __cu_len);		\
	__cu_len;							\
})

/*
 * __clear_user: - Zero a block of memory in user space, with less checking.
 * @to:   Destination address, in user space.
 * @n:    Number of bytes to zero.
 *
 * Zero a block of memory in user space.  Caller must check
 * the specified block with access_ok() before calling this function.
 *
 * Returns number of bytes that could not be cleared.
 * On success, this will be zero.
 */
static inline __kernel_size_t
__clear_user(void *addr, __kernel_size_t size)
{
	__kernel_size_t res;

	might_sleep();
	__asm__ __volatile__(
		"move\t$4, %1\n\t"
		"move\t$5, $0\n\t"
		"move\t$6, %2\n\t"
		__MODULE_JAL(__bzero)
		"move\t%0, $6"
		: "=r" (res)
		: "r" (addr), "r" (size)
		: "$4", "$5", "$6", __UA_t0, __UA_t1, "$31");

	return res;
}

#define clear_user(addr,n)						\
({									\
	void * __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, with less checking.
 * @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.
 * Caller must check the specified block with access_ok() before calling
 * this function.
 *
 * 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.
 */
static inline long
__strncpy_from_user(char *__to, const char *__from, long __len)
{
	long res;

	might_sleep();
	__asm__ __volatile__(
		"move\t$4, %1\n\t"
		"move\t$5, %2\n\t"
		"move\t$6, %3\n\t"
		__MODULE_JAL(__strncpy_from_user_nocheck_asm)
		"move\t%0, $2"
		: "=r" (res)
		: "r" (__to), "r" (__from), "r" (__len)
		: "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");

	return res;
}

/*
 * 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.
 */
static inline long
strncpy_from_user(char *__to, const char *__from, long __len)
{
	long res;

	might_sleep();
	__asm__ __volatile__(
		"move\t$4, %1\n\t"
		"move\t$5, %2\n\t"
		"move\t$6, %3\n\t"
		__MODULE_JAL(__strncpy_from_user_asm)
		"move\t%0, $2"
		: "=r" (res)
		: "r" (__to), "r" (__from), "r" (__len)
		: "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");

	return res;
}

/* Returns: 0 if bad, string length+1 (memory size) of string if ok */
static inline long __strlen_user(const char *s)
{
	long res;

	might_sleep();
	__asm__ __volatile__(
		"move\t$4, %1\n\t"
		__MODULE_JAL(__strlen_user_nocheck_asm)
		"move\t%0, $2"
		: "=r" (res)
		: "r" (s)
		: "$2", "$4", __UA_t0, "$31");

	return res;
}

/*
 * 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.
 */
static inline long strlen_user(const char *s)
{
	long res;

	might_sleep();
	__asm__ __volatile__(
		"move\t$4, %1\n\t"
		__MODULE_JAL(__strlen_user_asm)
		"move\t%0, $2"
		: "=r" (res)
		: "r" (s)
		: "$2", "$4", __UA_t0, "$31");

	return res;
}

/* Returns: 0 if bad, string length+1 (memory size) of string if ok */
static inline long __strnlen_user(const char *s, long n)
{
	long res;

	might_sleep();
	__asm__ __volatile__(
		"move\t$4, %1\n\t"
		"move\t$5, %2\n\t"
		__MODULE_JAL(__strnlen_user_nocheck_asm)
		"move\t%0, $2"
		: "=r" (res)
		: "r" (s), "r" (n)
		: "$2", "$4", "$5", __UA_t0, "$31");

	return res;
}

/*
 * 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.
 */
static inline long strnlen_user(const char *s, long n)
{
	long res;

	might_sleep();
	__asm__ __volatile__(
		"move\t$4, %1\n\t"
		"move\t$5, %2\n\t"
		__MODULE_JAL(__strnlen_user_asm)
		"move\t%0, $2"
		: "=r" (res)
		: "r" (s), "r" (n)
		: "$2", "$4", "$5", __UA_t0, "$31");

	return res;
}

struct exception_table_entry
{
	unsigned long insn;
	unsigned long nextinsn;
};

extern int fixup_exception(struct pt_regs *regs);

#endif /* _ASM_UACCESS_H */