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diff --git a/arch/tile/include/asm/uaccess.h b/arch/tile/include/asm/uaccess.h
new file mode 100644
index 000000000000..ef34d2caa5b1
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+++ b/arch/tile/include/asm/uaccess.h
@@ -0,0 +1,580 @@
+/*
+ * Copyright 2010 Tilera Corporation. All Rights Reserved.
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful, but
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ *   NON INFRINGEMENT.  See the GNU General Public License for
+ *   more details.
+ */
+
+#ifndef _ASM_TILE_UACCESS_H
+#define _ASM_TILE_UACCESS_H
+
+/*
+ * User space memory access functions
+ */
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <asm-generic/uaccess-unaligned.h>
+#include <asm/processor.h>
+#include <asm/page.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(-1UL)
+#define USER_DS         MAKE_MM_SEG(PAGE_OFFSET)
+
+#define get_ds()        (KERNEL_DS)
+#define get_fs()        (current_thread_info()->addr_limit)
+#define set_fs(x)       (current_thread_info()->addr_limit = (x))
+
+#define segment_eq(a, b) ((a).seg == (b).seg)
+
+#ifndef __tilegx__
+/*
+ * We could allow mapping all 16 MB at 0xfc000000, but we set up a
+ * special hack in arch_setup_additional_pages() to auto-create a mapping
+ * for the first 16 KB, and it would seem strange to have different
+ * user-accessible semantics for memory at 0xfc000000 and above 0xfc004000.
+ */
+static inline int is_arch_mappable_range(unsigned long addr,
+                                         unsigned long size)
+{
+        return (addr >= MEM_USER_INTRPT &&
+                addr < (MEM_USER_INTRPT + INTRPT_SIZE) &&
+                size <= (MEM_USER_INTRPT + INTRPT_SIZE) - addr);
+}
+#define is_arch_mappable_range is_arch_mappable_range
+#else
+#define is_arch_mappable_range(addr, size) 0
+#endif
+
+/*
+ * Test whether a block of memory is a valid user space address.
+ * Returns 0 if the range is valid, nonzero otherwise.
+ */
+int __range_ok(unsigned long addr, unsigned long size);
+
+/**
+ * access_ok: - Checks if a user space pointer is valid
+ * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE.  Note that
+ *        %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe
+ *        to write to a block, it is always safe to read from it.
+ * @addr: User space pointer to start of block to check
+ * @size: Size of block to check
+ *
+ * Context: User context only.  This function may sleep.
+ *
+ * Checks if a pointer to a block of memory in user space is valid.
+ *
+ * Returns true (nonzero) if the memory block may be valid, false (zero)
+ * if it is definitely invalid.
+ *
+ * Note that, depending on architecture, this function probably just
+ * checks that the pointer is in the user space range - after calling
+ * this function, memory access functions may still return -EFAULT.
+ */
+#define access_ok(type, addr, size) ({ \
+        __chk_user_ptr(addr); \
+        likely(__range_ok((unsigned long)(addr), (size)) == 0); \
+})
+
+/*
+ * 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;
+};
+
+extern int fixup_exception(struct pt_regs *regs);
+
+/*
+ * We return the __get_user_N function results in a structure,
+ * thus in r0 and r1.  If "err" is zero, "val" is the result
+ * of the read; otherwise, "err" is -EFAULT.
+ *
+ * We rarely need 8-byte values on a 32-bit architecture, but
+ * we size the structure to accommodate.  In practice, for the
+ * the smaller reads, we can zero the high word for free, and
+ * the caller will ignore it by virtue of casting anyway.
+ */
+struct __get_user {
+        unsigned long long val;
+        int err;
+};
+
+/*
+ * FIXME: we should express these as inline extended assembler, since
+ * they're fundamentally just a variable dereference and some
+ * supporting exception_table gunk.  Note that (a la i386) we can
+ * extend the copy_to_user and copy_from_user routines to call into
+ * such extended assembler routines, though we will have to use a
+ * different return code in that case (1, 2, or 4, rather than -EFAULT).
+ */
+extern struct __get_user __get_user_1(const void __user *);
+extern struct __get_user __get_user_2(const void __user *);
+extern struct __get_user __get_user_4(const void __user *);
+extern struct __get_user __get_user_8(const void __user *);
+extern int __put_user_1(long, void __user *);
+extern int __put_user_2(long, void __user *);
+extern int __put_user_4(long, void __user *);
+extern int __put_user_8(long long, void __user *);
+
+/* Unimplemented routines to cause linker failures */
+extern struct __get_user __get_user_bad(void);
+extern int __put_user_bad(void);
+
+/*
+ * Careful: we have to cast the result to the type of the pointer
+ * for sign reasons.
+ */
+/**
+ * __get_user: - Get a simple variable from user space, with less checking.
+ * @x:   Variable to store result.
+ * @ptr: Source address, in user space.
+ *
+ * Context: User context only.  This function may sleep.
+ *
+ * This macro copies a single simple variable from user space to kernel
+ * space.  It supports simple types like char and int, but not larger
+ * data types like structures or arrays.
+ *
+ * @ptr must have pointer-to-simple-variable type, and the result of
+ * dereferencing @ptr must be assignable to @x without a cast.
+ *
+ * Returns zero on success, or -EFAULT on error.
+ * On error, the variable @x is set to zero.
+ *
+ * Caller must check the pointer with access_ok() before calling this
+ * function.
+ */
+#define __get_user(x, ptr)                                              \
+({      struct __get_user __ret;                                        \
+        __typeof__(*(ptr)) const __user *__gu_addr = (ptr);             \
+        __chk_user_ptr(__gu_addr);                                      \
+        switch (sizeof(*(__gu_addr))) {                                 \
+        case 1:                                                         \
+                __ret = __get_user_1(__gu_addr);                        \
+                break;                                                  \
+        case 2:                                                         \
+                __ret = __get_user_2(__gu_addr);                        \
+                break;                                                  \
+        case 4:                                                         \
+                __ret = __get_user_4(__gu_addr);                        \
+                break;                                                  \
+        case 8:                                                         \
+                __ret = __get_user_8(__gu_addr);                        \
+                break;                                                  \
+        default:                                                        \
+                __ret = __get_user_bad();                               \
+                break;                                                  \
+        }                                                               \
+        (x) = (__typeof__(*__gu_addr)) (__typeof__(*__gu_addr - *__gu_addr)) \
+          __ret.val;                                                    \
+        __ret.err;                                                      \
+})
+
+/**
+ * __put_user: - Write a simple value into user space, with less checking.
+ * @x:   Value to copy to user space.
+ * @ptr: Destination address, in user space.
+ *
+ * Context: User context only.  This function may sleep.
+ *
+ * This macro copies a single simple value from kernel space to user
+ * space.  It supports simple types like char and int, but not larger
+ * data types like structures or arrays.
+ *
+ * @ptr must have pointer-to-simple-variable type, and @x must be assignable
+ * to the result of dereferencing @ptr.
+ *
+ * Caller must check the pointer with access_ok() before calling this
+ * function.
+ *
+ * Returns zero on success, or -EFAULT on error.
+ *
+ * Implementation note: The "case 8" logic of casting to the type of
+ * the result of subtracting the value from itself is basically a way
+ * of keeping all integer types the same, but casting any pointers to
+ * ptrdiff_t, i.e. also an integer type.  This way there are no
+ * questionable casts seen by the compiler on an ILP32 platform.
+ */
+#define __put_user(x, ptr)                                              \
+({                                                                      \
+        int __pu_err = 0;                                               \
+        __typeof__(*(ptr)) __user *__pu_addr = (ptr);                   \
+        typeof(*__pu_addr) __pu_val = (x);                              \
+        __chk_user_ptr(__pu_addr);                                      \
+        switch (sizeof(__pu_val)) {                                     \
+        case 1:                                                         \
+                __pu_err = __put_user_1((long)__pu_val, __pu_addr);     \
+                break;                                                  \
+        case 2:                                                         \
+                __pu_err = __put_user_2((long)__pu_val, __pu_addr);     \
+                break;                                                  \
+        case 4:                                                         \
+                __pu_err = __put_user_4((long)__pu_val, __pu_addr);     \
+                break;                                                  \
+        case 8:                                                         \
+                __pu_err =                                              \
+                  __put_user_8((__typeof__(__pu_val - __pu_val))__pu_val,\
+                        __pu_addr);                                     \
+                break;                                                  \
+        default:                                                        \
+                __pu_err = __put_user_bad();                            \
+                break;                                                  \
+        }                                                               \
+        __pu_err;                                                       \
+})
+
+/*
+ * The versions of get_user and put_user without initial underscores
+ * check the address of their arguments to make sure they are not
+ * in kernel space.
+ */
+#define put_user(x, ptr)                                                \
+({                                                                      \
+        __typeof__(*(ptr)) __user *__Pu_addr = (ptr);                   \
+        access_ok(VERIFY_WRITE, (__Pu_addr), sizeof(*(__Pu_addr))) ?    \
+                __put_user((x), (__Pu_addr)) :                          \
+                -EFAULT;                                                \
+})
+
+#define get_user(x, ptr)                                                \
+({                                                                      \
+        __typeof__(*(ptr)) const __user *__Gu_addr = (ptr);             \
+        access_ok(VERIFY_READ, (__Gu_addr), sizeof(*(__Gu_addr))) ?     \
+                __get_user((x), (__Gu_addr)) :                          \
+                ((x) = 0, -EFAULT);                                     \
+})
+
+/**
+ * __copy_to_user() - copy 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.
+ *
+ * An alternate version - __copy_to_user_inatomic() - is designed
+ * to be called from atomic context, typically bracketed by calls
+ * to pagefault_disable() and pagefault_enable().
+ */
+extern unsigned long __must_check __copy_to_user_inatomic(
+        void __user *to, const void *from, unsigned long n);
+
+static inline unsigned long __must_check
+__copy_to_user(void __user *to, const void *from, unsigned long n)
+{
+        might_fault();
+        return __copy_to_user_inatomic(to, from, n);
+}
+
+static inline unsigned long __must_check
+copy_to_user(void __user *to, const void *from, unsigned long n)
+{
+        if (access_ok(VERIFY_WRITE, to, n))
+                n = __copy_to_user(to, from, n);
+        return n;
+}
+
+/**
+ * __copy_from_user() - copy 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.
+ *
+ * An alternate version - __copy_from_user_inatomic() - is designed
+ * to be called from atomic context, typically bracketed by calls
+ * to pagefault_disable() and pagefault_enable().  This version
+ * does *NOT* pad with zeros.
+ */
+extern unsigned long __must_check __copy_from_user_inatomic(
+        void *to, const void __user *from, unsigned long n);
+extern unsigned long __must_check __copy_from_user_zeroing(
+        void *to, const void __user *from, unsigned long n);
+
+static inline unsigned long __must_check
+__copy_from_user(void *to, const void __user *from, unsigned long n)
+{
+       might_fault();
+       return __copy_from_user_zeroing(to, from, n);
+}
+
+static inline unsigned long __must_check
+_copy_from_user(void *to, const void __user *from, unsigned long n)
+{
+        if (access_ok(VERIFY_READ, from, n))
+                n = __copy_from_user(to, from, n);
+        else
+                memset(to, 0, n);
+        return n;
+}
+
+#ifdef CONFIG_DEBUG_COPY_FROM_USER
+extern void copy_from_user_overflow(void)
+        __compiletime_warning("copy_from_user() size is not provably correct");
+
+static inline unsigned long __must_check copy_from_user(void *to,
+                                          const void __user *from,
+                                          unsigned long n)
+{
+        int sz = __compiletime_object_size(to);
+
+        if (likely(sz == -1 || sz >= n))
+                n = _copy_from_user(to, from, n);
+        else
+                copy_from_user_overflow();
+
+        return n;
+}
+#else
+#define copy_from_user _copy_from_user
+#endif
+
+#ifdef __tilegx__
+/**
+ * __copy_in_user() - copy data within 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 user space to user space.  Caller must check
+ * the specified blocks with access_ok() before calling this function.
+ *
+ * Returns number of bytes that could not be copied.
+ * On success, this will be zero.
+ */
+extern unsigned long __copy_in_user_inatomic(
+        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_sleep();
+        return __copy_in_user_inatomic(to, from, n);
+}
+
+static inline unsigned long __must_check
+copy_in_user(void __user *to, const void __user *from, unsigned long n)
+{
+        if (access_ok(VERIFY_WRITE, to, n) && access_ok(VERIFY_READ, from, n))
+                n = __copy_in_user(to, from, n);
+        return n;
+}
+#endif
+
+
+/**
+ * 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.
+ */
+extern long strnlen_user_asm(const char __user *str, long n);
+static inline long __must_check strnlen_user(const char __user *str, long n)
+{
+        might_fault();
+        return strnlen_user_asm(str, n);
+}
+#define strlen_user(str) strnlen_user(str, LONG_MAX)
+
+/**
+ * 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.
+ */
+extern long strncpy_from_user_asm(char *dst, const char __user *src, long);
+static inline long __must_check __strncpy_from_user(
+        char *dst, const char __user *src, long count)
+{
+        might_fault();
+        return strncpy_from_user_asm(dst, src, count);
+}
+static inline long __must_check strncpy_from_user(
+        char *dst, const char __user *src, long count)
+{
+        if (access_ok(VERIFY_READ, src, 1))
+                return __strncpy_from_user(dst, src, count);
+        return -EFAULT;
+}
+
+/**
+ * clear_user: - Zero a block of memory in user space.
+ * @mem:   Destination address, in user space.
+ * @len:   Number of bytes to zero.
+ *
+ * Zero a block of memory in user space.
+ *
+ * Returns number of bytes that could not be cleared.
+ * On success, this will be zero.
+ */
+extern unsigned long clear_user_asm(void __user *mem, unsigned long len);
+static inline unsigned long __must_check __clear_user(
+        void __user *mem, unsigned long len)
+{
+        might_fault();
+        return clear_user_asm(mem, len);
+}
+static inline unsigned long __must_check clear_user(
+        void __user *mem, unsigned long len)
+{
+        if (access_ok(VERIFY_WRITE, mem, len))
+                return __clear_user(mem, len);
+        return len;
+}
+
+/**
+ * flush_user: - Flush a block of memory in user space from cache.
+ * @mem:   Destination address, in user space.
+ * @len:   Number of bytes to flush.
+ *
+ * Returns number of bytes that could not be flushed.
+ * On success, this will be zero.
+ */
+extern unsigned long flush_user_asm(void __user *mem, unsigned long len);
+static inline unsigned long __must_check __flush_user(
+        void __user *mem, unsigned long len)
+{
+        int retval;
+
+        might_fault();
+        retval = flush_user_asm(mem, len);
+        mb_incoherent();
+        return retval;
+}
+
+static inline unsigned long __must_check flush_user(
+        void __user *mem, unsigned long len)
+{
+        if (access_ok(VERIFY_WRITE, mem, len))
+                return __flush_user(mem, len);
+        return len;
+}
+
+/**
+ * inv_user: - Invalidate a block of memory in user space from cache.
+ * @mem:   Destination address, in user space.
+ * @len:   Number of bytes to invalidate.
+ *
+ * Returns number of bytes that could not be invalidated.
+ * On success, this will be zero.
+ *
+ * Note that on Tile64, the "inv" operation is in fact a
+ * "flush and invalidate", so cache write-backs will occur prior
+ * to the cache being marked invalid.
+ */
+extern unsigned long inv_user_asm(void __user *mem, unsigned long len);
+static inline unsigned long __must_check __inv_user(
+        void __user *mem, unsigned long len)
+{
+        int retval;
+
+        might_fault();
+        retval = inv_user_asm(mem, len);
+        mb_incoherent();
+        return retval;
+}
+static inline unsigned long __must_check inv_user(
+        void __user *mem, unsigned long len)
+{
+        if (access_ok(VERIFY_WRITE, mem, len))
+                return __inv_user(mem, len);
+        return len;
+}
+
+/**
+ * finv_user: - Flush-inval a block of memory in user space from cache.
+ * @mem:   Destination address, in user space.
+ * @len:   Number of bytes to invalidate.
+ *
+ * Returns number of bytes that could not be flush-invalidated.
+ * On success, this will be zero.
+ */
+extern unsigned long finv_user_asm(void __user *mem, unsigned long len);
+static inline unsigned long __must_check __finv_user(
+        void __user *mem, unsigned long len)
+{
+        int retval;
+
+        might_fault();
+        retval = finv_user_asm(mem, len);
+        mb_incoherent();
+        return retval;
+}
+static inline unsigned long __must_check finv_user(
+        void __user *mem, unsigned long len)
+{
+        if (access_ok(VERIFY_WRITE, mem, len))
+                return __finv_user(mem, len);
+        return len;
+}
+
+#endif /* _ASM_TILE_UACCESS_H */