patch-2.1.80 linux/include/asm-arm/uaccess.h

• Lines: 195
• Date: Tue Jan 20 16:39:43 1998
• Orig file: v2.1.79/linux/include/asm-arm/uaccess.h
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.1.79/linux/include/asm-arm/uaccess.h linux/include/asm-arm/uaccess.h
@@ -0,0 +1,194 @@
+#ifndef _ASMARM_UACCESS_H
+#define _ASMARM_UACCESS_H
+
+/*
+ * User space memory access functions
+ */
+#include <linux/sched.h>
+
+#define VERIFY_READ 0
+#define VERIFY_WRITE 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;
+};
+
+/* Returns 0 if exception not found and fixup otherwise.  */
+extern unsigned long search_exception_table(unsigned long);
+
+#include <asm/proc/uaccess.h>
+
+extern inline int verify_area(int type, const void * addr, unsigned long size)
+{
+	return access_ok(type,addr,size) ? 0 : -EFAULT;
+}
+
+/*
+ * Single-value transfer routines.  They automatically use the right
+ * size if we just have the right pointer type.
+ *
+ * The "__xxx" versions of the user access functions do not verify the
+ * address space - it must have been done previously with a separate
+ * "access_ok()" call.
+ *
+ * The "xxx_ret" versions return constant specified in the third
+ * argument if something bad happens.
+ */
+#define get_user(x,p)		__get_user_check((x),(p),sizeof(*(p)))
+#define __get_user(x,p)		__get_user_nocheck((x),(p),sizeof(*(p)))
+#define get_user_ret(x,p,r)	({ if (get_user(x,p)) return r; })
+#define __get_user_ret(x,p,r)	({ if (__get_user(x,p)) return r; })
+
+#define put_user(x,p)		__put_user_check((__typeof(*(p)))(x),(p),sizeof(*(p)))
+#define __put_user(x,p)		__put_user_nocheck((__typeof(*(p)))(x),(p),sizeof(*(p)))
+#define put_user_ret(x,p,r)	({ if (put_user(x,p)) return r; })
+#define __put_user_ret(x,p,r)	({ if (__put_user(x,p)) return r; })
+
+static __inline__ unsigned long copy_from_user(void *to, const void *from, unsigned long n)
+{
+	if (access_ok(VERIFY_READ, from, n))
+		__do_copy_from_user(to, from, n);
+	return n;
+}
+
+static __inline__ unsigned long __copy_from_user(void *to, const void *from, unsigned long n)
+{
+	__do_copy_from_user(to, from, n);
+	return n;
+}
+
+#define copy_from_user_ret(t,f,n,r)					\
+	({ if (copy_from_user(t,f,n)) return r; })
+
+static __inline__ unsigned long copy_to_user(void *to, const void *from, unsigned long n)
+{
+	if (access_ok(VERIFY_WRITE, to, n))
+		__do_copy_to_user(to, from, n);
+	return n;
+}
+
+static __inline__ unsigned long __copy_to_user(void *to, const void *from, unsigned long n)
+{
+	__do_copy_to_user(to, from, n);
+	return n;
+}
+
+#define copy_to_user_ret(t,f,n,r)					\
+	({ if (copy_to_user(t,f,n)) return r; })
+
+static __inline__ unsigned long clear_user (void *to, unsigned long n)
+{
+	if (access_ok(VERIFY_WRITE, to, n))
+		__do_clear_user(to, n);
+	return n;
+}
+
+static __inline__ unsigned long __clear_user (void *to, unsigned long n)
+{
+	__do_clear_user(to, n);
+	return n;
+}
+
+static __inline__ long strncpy_from_user (char *dst, const char *src, long count)
+{
+	long res = -EFAULT;
+	if (access_ok(VERIFY_READ, src, 1))
+		__do_strncpy_from_user(dst, src, count, res);
+	return res;
+}
+
+static __inline__ long __strncpy_from_user (char *dst, const char *src, long count)
+{
+	long res;
+	__do_strncpy_from_user(dst, src, count, res);
+	return res;
+}
+
+extern __inline__ long strlen_user (const char *s)
+{
+	unsigned long res = 0;
+
+	if (__addr_ok(s))
+		__do_strlen_user (s, res);
+
+	return res;
+}
+
+/*
+ * These are the work horses of the get/put_user functions
+ */
+#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;							\
+})
+
+#define __get_user_nocheck(x,ptr,size)					\
+({									\
+	long __gu_err = 0, __gu_val = 0;				\
+	__get_user_size(__gu_val,(ptr),(size),__gu_err);		\
+	(x) = (__typeof__(*(ptr)))__gu_val;				\
+	__gu_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;							\
+})
+
+#define __put_user_nocheck(x,ptr,size)					\
+({									\
+	long __pu_err = 0;						\
+	__put_user_size((x),(ptr),(size),__pu_err);			\
+	__pu_err;							\
+})
+
+extern long __get_user_bad(void);
+
+#define __get_user_size(x,ptr,size,retval)				\
+do {									\
+	retval = 0;							\
+	switch (size) {							\
+	case 1:	__get_user_asm_byte(x,ptr,retval);	break;		\
+	case 2:	__get_user_asm_half(x,ptr,retval);	break;		\
+	case 4:	__get_user_asm_word(x,ptr,retval);	break;		\
+	default: (x) = __get_user_bad();				\
+	}								\
+} while (0)
+
+extern long __put_user_bad(void);
+
+#define __put_user_size(x,ptr,size,retval)				\
+do {									\
+	retval = 0;							\
+	switch (size) {							\
+	case 1: __put_user_asm_byte(x,ptr,retval);	break;		\
+	case 2: __put_user_asm_half(x,ptr,retval);	break;		\
+	case 4: __put_user_asm_word(x,ptr,retval);	break;		\
+	default: __put_user_bad();					\
+	}								\
+} while (0)
+
+#endif /* _ASMARM_UACCESS_H */