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-rw-r--r--include/asm-s390/uaccess.h436
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+/*
+ * include/asm-s390/uaccess.h
+ *
+ * S390 version
+ * Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ * 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>
+
+#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)
+
+#ifdef __s390x__
+#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; \
+ asm volatile ("lctlg 7,7,%0" : : "m" (__pto) ); \
+})
+#else
+#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; \
+ asm volatile ("lctl 7,7,%0" : : "m" (__pto) ); \
+})
+#endif
+
+#define segment_eq(a,b) ((a).ar4 == (b).ar4)
+
+
+#define __access_ok(addr,size) (1)
+
+#define access_ok(type,addr,size) __access_ok(addr,size)
+
+/* this function will go away soon - use access_ok() instead */
+extern inline int __deprecated verify_area(int type, const void __user *addr,
+ unsigned long size)
+{
+ return access_ok(type, addr, size) ? 0 : -EFAULT;
+}
+
+/*
+ * 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;
+};
+
+#ifndef __s390x__
+#define __uaccess_fixup \
+ ".section .fixup,\"ax\"\n" \
+ "2: lhi %0,%4\n" \
+ " bras 1,3f\n" \
+ " .long 1b\n" \
+ "3: l 1,0(1)\n" \
+ " br 1\n" \
+ ".previous\n" \
+ ".section __ex_table,\"a\"\n" \
+ " .align 4\n" \
+ " .long 0b,2b\n" \
+ ".previous"
+#define __uaccess_clobber "cc", "1"
+#else /* __s390x__ */
+#define __uaccess_fixup \
+ ".section .fixup,\"ax\"\n" \
+ "2: lghi %0,%4\n" \
+ " jg 1b\n" \
+ ".previous\n" \
+ ".section __ex_table,\"a\"\n" \
+ " .align 8\n" \
+ " .quad 0b,2b\n" \
+ ".previous"
+#define __uaccess_clobber "cc"
+#endif /* __s390x__ */
+
+/*
+ * These are the main single-value transfer routines. They automatically
+ * use the right size if we just have the right pointer type.
+ */
+#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ > 2)
+#define __put_user_asm(x, ptr, err) \
+({ \
+ err = 0; \
+ asm volatile( \
+ "0: mvcs 0(%1,%2),%3,%0\n" \
+ "1:\n" \
+ __uaccess_fixup \
+ : "+&d" (err) \
+ : "d" (sizeof(*(ptr))), "a" (ptr), "Q" (x), \
+ "K" (-EFAULT) \
+ : __uaccess_clobber ); \
+})
+#else
+#define __put_user_asm(x, ptr, err) \
+({ \
+ err = 0; \
+ asm volatile( \
+ "0: mvcs 0(%1,%2),0(%3),%0\n" \
+ "1:\n" \
+ __uaccess_fixup \
+ : "+&d" (err) \
+ : "d" (sizeof(*(ptr))), "a" (ptr), "a" (&(x)), \
+ "K" (-EFAULT), "m" (x) \
+ : __uaccess_clobber ); \
+})
+#endif
+
+#ifndef __CHECKER__
+#define __put_user(x, ptr) \
+({ \
+ __typeof__(*(ptr)) __x = (x); \
+ int __pu_err; \
+ switch (sizeof (*(ptr))) { \
+ case 1: \
+ case 2: \
+ case 4: \
+ case 8: \
+ __put_user_asm(__x, ptr, __pu_err); \
+ break; \
+ default: \
+ __put_user_bad(); \
+ break; \
+ } \
+ __pu_err; \
+})
+#else
+#define __put_user(x, ptr) \
+({ \
+ void __user *p; \
+ p = (ptr); \
+ 0; \
+})
+#endif
+
+#define put_user(x, ptr) \
+({ \
+ might_sleep(); \
+ __put_user(x, ptr); \
+})
+
+
+extern int __put_user_bad(void) __attribute__((noreturn));
+
+#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ > 2)
+#define __get_user_asm(x, ptr, err) \
+({ \
+ err = 0; \
+ asm volatile ( \
+ "0: mvcp %O1(%2,%R1),0(%3),%0\n" \
+ "1:\n" \
+ __uaccess_fixup \
+ : "+&d" (err), "=Q" (x) \
+ : "d" (sizeof(*(ptr))), "a" (ptr), \
+ "K" (-EFAULT) \
+ : __uaccess_clobber ); \
+})
+#else
+#define __get_user_asm(x, ptr, err) \
+({ \
+ err = 0; \
+ asm volatile ( \
+ "0: mvcp 0(%2,%5),0(%3),%0\n" \
+ "1:\n" \
+ __uaccess_fixup \
+ : "+&d" (err), "=m" (x) \
+ : "d" (sizeof(*(ptr))), "a" (ptr), \
+ "K" (-EFAULT), "a" (&(x)) \
+ : __uaccess_clobber ); \
+})
+#endif
+
+#ifndef __CHECKER__
+#define __get_user(x, ptr) \
+({ \
+ __typeof__(*(ptr)) __x; \
+ int __gu_err; \
+ switch (sizeof(*(ptr))) { \
+ case 1: \
+ case 2: \
+ case 4: \
+ case 8: \
+ __get_user_asm(__x, ptr, __gu_err); \
+ break; \
+ default: \
+ __get_user_bad(); \
+ break; \
+ } \
+ (x) = __x; \
+ __gu_err; \
+})
+#else
+#define __get_user(x, ptr) \
+({ \
+ void __user *p; \
+ p = (ptr); \
+ 0; \
+})
+#endif
+
+
+#define get_user(x, ptr) \
+({ \
+ might_sleep(); \
+ __get_user(x, ptr); \
+})
+
+extern int __get_user_bad(void) __attribute__((noreturn));
+
+#define __put_user_unaligned __put_user
+#define __get_user_unaligned __get_user
+
+extern long __copy_to_user_asm(const void *from, long n, void __user *to);
+
+/**
+ * __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.
+ */
+static inline unsigned long
+__copy_to_user(void __user *to, const void *from, unsigned long n)
+{
+ return __copy_to_user_asm(from, n, to);
+}
+
+#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.
+ */
+static inline unsigned long
+copy_to_user(void __user *to, const void *from, unsigned long n)
+{
+ might_sleep();
+ if (access_ok(VERIFY_WRITE, to, n))
+ n = __copy_to_user(to, from, n);
+ return n;
+}
+
+extern long __copy_from_user_asm(void *to, long n, const void __user *from);
+
+/**
+ * __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.
+ */
+static inline unsigned long
+__copy_from_user(void *to, const void __user *from, unsigned long n)
+{
+ return __copy_from_user_asm(to, n, from);
+}
+
+/**
+ * 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
+copy_from_user(void *to, const void __user *from, unsigned long n)
+{
+ might_sleep();
+ if (access_ok(VERIFY_READ, from, n))
+ n = __copy_from_user(to, from, n);
+ else
+ memset(to, 0, n);
+ return n;
+}
+
+extern unsigned long __copy_in_user_asm(const void __user *from, long n,
+ void __user *to);
+
+static inline unsigned long
+__copy_in_user(void __user *to, const void __user *from, unsigned long n)
+{
+ return __copy_in_user_asm(from, n, to);
+}
+
+static inline unsigned long
+copy_in_user(void __user *to, const void __user *from, unsigned long n)
+{
+ might_sleep();
+ if (__access_ok(from,n) && __access_ok(to,n))
+ n = __copy_in_user_asm(from, n, to);
+ return n;
+}
+
+/*
+ * Copy a null terminated string from userspace.
+ */
+extern long __strncpy_from_user_asm(long count, char *dst,
+ const char __user *src);
+
+static inline long
+strncpy_from_user(char *dst, const char __user *src, long count)
+{
+ long res = -EFAULT;
+ might_sleep();
+ if (access_ok(VERIFY_READ, src, 1))
+ res = __strncpy_from_user_asm(count, dst, src);
+ return res;
+}
+
+
+extern long __strnlen_user_asm(long count, const char __user *src);
+
+static inline unsigned long
+strnlen_user(const char __user * src, unsigned long n)
+{
+ might_sleep();
+ return __strnlen_user_asm(n, src);
+}
+
+/**
+ * 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
+ */
+
+extern long __clear_user_asm(void __user *to, long n);
+
+static inline unsigned long
+__clear_user(void __user *to, unsigned long n)
+{
+ return __clear_user_asm(to, n);
+}
+
+static inline unsigned long
+clear_user(void __user *to, unsigned long n)
+{
+ might_sleep();
+ if (access_ok(VERIFY_WRITE, to, n))
+ n = __clear_user_asm(to, n);
+ return n;
+}
+
+#endif /* __S390_UACCESS_H */
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