Initial import

1 files changed, 377 insertions, 0 deletions

diff --git a/arch/s390/include/asm/uaccess.h b/arch/s390/include/asm/uaccess.h
new file mode 100644
index 000000000..d64a7a621
--- /dev/null
+++ b/arch/s390/include/asm/uaccess.h
@@ -0,0 +1,377 @@
+/*
+ *  S390 version
+ *    Copyright IBM Corp. 1999, 2000
+ *    Author(s): Hartmut Penner (hp@de.ibm.com),
+ *               Martin Schwidefsky (schwidefsky@de.ibm.com)
+ *
+ *  Derived from "include/asm-i386/uaccess.h"
+ */
+#ifndef __S390_UACCESS_H
+#define __S390_UACCESS_H
+
+/*
+ * User space memory access functions
+ */
+#include <linux/sched.h>
+#include <linux/errno.h>
+#include <asm/ctl_reg.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(a)  ((mm_segment_t) { (a) })
+
+
+#define KERNEL_DS       MAKE_MM_SEG(0)
+#define USER_DS         MAKE_MM_SEG(1)
+
+#define get_ds()        (KERNEL_DS)
+#define get_fs()        (current->thread.mm_segment)
+
+#define set_fs(x) \
+({									\
+	unsigned long __pto;						\
+	current->thread.mm_segment = (x);				\
+	__pto = current->thread.mm_segment.ar4 ?			\
+		S390_lowcore.user_asce : S390_lowcore.kernel_asce;	\
+	__ctl_load(__pto, 7, 7);					\
+})
+
+#define segment_eq(a,b) ((a).ar4 == (b).ar4)
+
+static inline int __range_ok(unsigned long addr, unsigned long size)
+{
+	return 1;
+}
+
+#define __access_ok(addr, size)				\
+({							\
+	__chk_user_ptr(addr);				\
+	__range_ok((unsigned long)(addr), (size));	\
+})
+
+#define access_ok(type, addr, size) __access_ok(addr, size)
+
+/*
+ * 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
+{
+	int insn, fixup;
+};
+
+static inline unsigned long extable_insn(const struct exception_table_entry *x)
+{
+	return (unsigned long)&x->insn + x->insn;
+}
+
+static inline unsigned long extable_fixup(const struct exception_table_entry *x)
+{
+	return (unsigned long)&x->fixup + x->fixup;
+}
+
+#define ARCH_HAS_SORT_EXTABLE
+#define ARCH_HAS_SEARCH_EXTABLE
+
+/**
+ * __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.
+ */
+unsigned long __must_check __copy_from_user(void *to, const void __user *from,
+					    unsigned long n);
+
+/**
+ * __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.
+ */
+unsigned long __must_check __copy_to_user(void __user *to, const void *from,
+					  unsigned long n);
+
+#define __copy_to_user_inatomic __copy_to_user
+#define __copy_from_user_inatomic __copy_from_user
+
+#ifdef CONFIG_HAVE_MARCH_Z10_FEATURES
+
+#define __put_get_user_asm(to, from, size, spec)		\
+({								\
+	register unsigned long __reg0 asm("0") = spec;		\
+	int __rc;						\
+								\
+	asm volatile(						\
+		"0:	mvcos	%1,%3,%2\n"			\
+		"1:	xr	%0,%0\n"			\
+		"2:\n"						\
+		".pushsection .fixup, \"ax\"\n"			\
+		"3:	lhi	%0,%5\n"			\
+		"	jg	2b\n"				\
+		".popsection\n"					\
+		EX_TABLE(0b,3b) EX_TABLE(1b,3b)			\
+		: "=d" (__rc), "=Q" (*(to))			\
+		: "d" (size), "Q" (*(from)),			\
+		  "d" (__reg0), "K" (-EFAULT)			\
+		: "cc");					\
+	__rc;							\
+})
+
+#define __put_user_fn(x, ptr, size) __put_get_user_asm(ptr, x, size, 0x810000UL)
+#define __get_user_fn(x, ptr, size) __put_get_user_asm(x, ptr, size, 0x81UL)
+
+#else /* CONFIG_HAVE_MARCH_Z10_FEATURES */
+
+static inline int __put_user_fn(void *x, void __user *ptr, unsigned long size)
+{
+	size = __copy_to_user(ptr, x, size);
+	return size ? -EFAULT : 0;
+}
+
+static inline int __get_user_fn(void *x, const void __user *ptr, unsigned long size)
+{
+	size = __copy_from_user(x, ptr, size);
+	return size ? -EFAULT : 0;
+}
+
+#endif /* CONFIG_HAVE_MARCH_Z10_FEATURES */
+
+/*
+ * These are the main single-value transfer routines.  They automatically
+ * use the right size if we just have the right pointer type.
+ */
+#define __put_user(x, ptr) \
+({								\
+	__typeof__(*(ptr)) __x = (x);				\
+	int __pu_err = -EFAULT;					\
+        __chk_user_ptr(ptr);                                    \
+	switch (sizeof (*(ptr))) {				\
+	case 1:							\
+	case 2:							\
+	case 4:							\
+	case 8:							\
+		__pu_err = __put_user_fn(&__x, ptr,		\
+					 sizeof(*(ptr)));	\
+		break;						\
+	default:						\
+		__put_user_bad();				\
+		break;						\
+	 }							\
+	__pu_err;						\
+})
+
+#define put_user(x, ptr)					\
+({								\
+	might_fault();						\
+	__put_user(x, ptr);					\
+})
+
+
+int __put_user_bad(void) __attribute__((noreturn));
+
+#define __get_user(x, ptr)					\
+({								\
+	int __gu_err = -EFAULT;					\
+	__chk_user_ptr(ptr);					\
+	switch (sizeof(*(ptr))) {				\
+	case 1: {						\
+		unsigned char __x;				\
+		__gu_err = __get_user_fn(&__x, ptr,		\
+					 sizeof(*(ptr)));	\
+		(x) = *(__force __typeof__(*(ptr)) *) &__x;	\
+		break;						\
+	};							\
+	case 2: {						\
+		unsigned short __x;				\
+		__gu_err = __get_user_fn(&__x, ptr,		\
+					 sizeof(*(ptr)));	\
+		(x) = *(__force __typeof__(*(ptr)) *) &__x;	\
+		break;						\
+	};							\
+	case 4: {						\
+		unsigned int __x;				\
+		__gu_err = __get_user_fn(&__x, ptr,		\
+					 sizeof(*(ptr)));	\
+		(x) = *(__force __typeof__(*(ptr)) *) &__x;	\
+		break;						\
+	};							\
+	case 8: {						\
+		unsigned long long __x;				\
+		__gu_err = __get_user_fn(&__x, ptr,		\
+					 sizeof(*(ptr)));	\
+		(x) = *(__force __typeof__(*(ptr)) *) &__x;	\
+		break;						\
+	};							\
+	default:						\
+		__get_user_bad();				\
+		break;						\
+	}							\
+	__gu_err;						\
+})
+
+#define get_user(x, ptr)					\
+({								\
+	might_fault();						\
+	__get_user(x, ptr);					\
+})
+
+int __get_user_bad(void) __attribute__((noreturn));
+
+#define __put_user_unaligned __put_user
+#define __get_user_unaligned __get_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.
+ */
+static inline unsigned long __must_check
+copy_to_user(void __user *to, const void *from, unsigned long n)
+{
+	might_fault();
+	return __copy_to_user(to, from, n);
+}
+
+void copy_from_user_overflow(void)
+#ifdef CONFIG_DEBUG_STRICT_USER_COPY_CHECKS
+__compiletime_warning("copy_from_user() buffer size is not provably correct")
+#endif
+;
+
+/**
+ * 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.
+ */
+static inline unsigned long __must_check
+copy_from_user(void *to, const void __user *from, unsigned long n)
+{
+	unsigned int sz = __compiletime_object_size(to);
+
+	might_fault();
+	if (unlikely(sz != -1 && sz < n)) {
+		copy_from_user_overflow();
+		return n;
+	}
+	return __copy_from_user(to, from, n);
+}
+
+unsigned long __must_check
+__copy_in_user(void __user *to, const void __user *from, unsigned long n);
+
+static inline unsigned long __must_check
+copy_in_user(void __user *to, const void __user *from, unsigned long n)
+{
+	might_fault();
+	return __copy_in_user(to, from, n);
+}
+
+/*
+ * Copy a null terminated string from userspace.
+ */
+
+long __strncpy_from_user(char *dst, const char __user *src, long count);
+
+static inline long __must_check
+strncpy_from_user(char *dst, const char __user *src, long count)
+{
+	might_fault();
+	return __strncpy_from_user(dst, src, count);
+}
+
+unsigned long __must_check __strnlen_user(const char __user *src, unsigned long count);
+
+static inline unsigned long strnlen_user(const char __user *src, unsigned long n)
+{
+	might_fault();
+	return __strnlen_user(src, 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)
+
+/*
+ * Zero Userspace
+ */
+unsigned long __must_check __clear_user(void __user *to, unsigned long size);
+
+static inline unsigned long __must_check clear_user(void __user *to, unsigned long n)
+{
+	might_fault();
+	return __clear_user(to, n);
+}
+
+int copy_to_user_real(void __user *dest, void *src, unsigned long count);
+void s390_kernel_write(void *dst, const void *src, size_t size);
+
+#endif /* __S390_UACCESS_H */