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diff --git a/include/asm-xtensa/uaccess.h b/include/asm-xtensa/uaccess.h
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--- a/include/asm-xtensa/uaccess.h
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-/*
- * include/asm-xtensa/uaccess.h
- *
- * User space memory access functions
- *
- * These routines provide basic accessing functions to the user memory
- * space for the kernel. This header file provides fuctions such as:
- *
- * This file is subject to the terms and conditions of the GNU General Public
- * License. See the file "COPYING" in the main directory of this archive
- * for more details.
- *
- * Copyright (C) 2001 - 2005 Tensilica Inc.
- */
-
-#ifndef _XTENSA_UACCESS_H
-#define _XTENSA_UACCESS_H
-
-#include <linux/errno.h>
-
-#define VERIFY_READ 0
-#define VERIFY_WRITE 1
-
-#ifdef __ASSEMBLY__
-
-#include <asm/current.h>
-#include <asm/asm-offsets.h>
-#include <asm/processor.h>
-#include <asm/types.h>
-
-/*
- * These assembly macros mirror the C macros that follow below. They
- * should always have identical functionality. See
- * arch/xtensa/kernel/sys.S for usage.
- */
-
-#define KERNEL_DS 0
-#define USER_DS 1
-
-#define get_ds (KERNEL_DS)
-
-/*
- * get_fs reads current->thread.current_ds into a register.
- * On Entry:
- * <ad> anything
- * <sp> stack
- * On Exit:
- * <ad> contains current->thread.current_ds
- */
- .macro get_fs ad, sp
- GET_CURRENT(\ad,\sp)
- l32i \ad, \ad, THREAD_CURRENT_DS
- .endm
-
-/*
- * set_fs sets current->thread.current_ds to some value.
- * On Entry:
- * <at> anything (temp register)
- * <av> value to write
- * <sp> stack
- * On Exit:
- * <at> destroyed (actually, current)
- * <av> preserved, value to write
- */
- .macro set_fs at, av, sp
- GET_CURRENT(\at,\sp)
- s32i \av, \at, THREAD_CURRENT_DS
- .endm
-
-/*
- * kernel_ok determines whether we should bypass addr/size checking.
- * See the equivalent C-macro version below for clarity.
- * On success, kernel_ok branches to a label indicated by parameter
- * <success>. This implies that the macro falls through to the next
- * insruction on an error.
- *
- * Note that while this macro can be used independently, we designed
- * in for optimal use in the access_ok macro below (i.e., we fall
- * through on error).
- *
- * On Entry:
- * <at> anything (temp register)
- * <success> label to branch to on success; implies
- * fall-through macro on error
- * <sp> stack pointer
- * On Exit:
- * <at> destroyed (actually, current->thread.current_ds)
- */
-
-#if ((KERNEL_DS != 0) || (USER_DS == 0))
-# error Assembly macro kernel_ok fails
-#endif
- .macro kernel_ok at, sp, success
- get_fs \at, \sp
- beqz \at, \success
- .endm
-
-/*
- * user_ok determines whether the access to user-space memory is allowed.
- * See the equivalent C-macro version below for clarity.
- *
- * On error, user_ok branches to a label indicated by parameter
- * <error>. This implies that the macro falls through to the next
- * instruction on success.
- *
- * Note that while this macro can be used independently, we designed
- * in for optimal use in the access_ok macro below (i.e., we fall
- * through on success).
- *
- * On Entry:
- * <aa> register containing memory address
- * <as> register containing memory size
- * <at> temp register
- * <error> label to branch to on error; implies fall-through
- * macro on success
- * On Exit:
- * <aa> preserved
- * <as> preserved
- * <at> destroyed (actually, (TASK_SIZE + 1 - size))
- */
- .macro user_ok aa, as, at, error
- movi \at, __XTENSA_UL_CONST(TASK_SIZE)
- bgeu \as, \at, \error
- sub \at, \at, \as
- bgeu \aa, \at, \error
- .endm
-
-/*
- * access_ok determines whether a memory access is allowed. See the
- * equivalent C-macro version below for clarity.
- *
- * On error, access_ok branches to a label indicated by parameter
- * <error>. This implies that the macro falls through to the next
- * instruction on success.
- *
- * Note that we assume success is the common case, and we optimize the
- * branch fall-through case on success.
- *
- * On Entry:
- * <aa> register containing memory address
- * <as> register containing memory size
- * <at> temp register
- * <sp>
- * <error> label to branch to on error; implies fall-through
- * macro on success
- * On Exit:
- * <aa> preserved
- * <as> preserved
- * <at> destroyed
- */
- .macro access_ok aa, as, at, sp, error
- kernel_ok \at, \sp, .Laccess_ok_\@
- user_ok \aa, \as, \at, \error
-.Laccess_ok_\@:
- .endm
-
-#else /* __ASSEMBLY__ not defined */
-
-#include <linux/sched.h>
-#include <asm/types.h>
-
-/*
- * 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 (Data Segment Register?), these macros are
- * grossly misnamed.
- */
-
-#define KERNEL_DS ((mm_segment_t) { 0 })
-#define USER_DS ((mm_segment_t) { 1 })
-
-#define get_ds() (KERNEL_DS)
-#define get_fs() (current->thread.current_ds)
-#define set_fs(val) (current->thread.current_ds = (val))
-
-#define segment_eq(a,b) ((a).seg == (b).seg)
-
-#define __kernel_ok (segment_eq(get_fs(), KERNEL_DS))
-#define __user_ok(addr,size) (((size) <= TASK_SIZE)&&((addr) <= TASK_SIZE-(size)))
-#define __access_ok(addr,size) (__kernel_ok || __user_ok((addr),(size)))
-#define access_ok(type,addr,size) __access_ok((unsigned long)(addr),(size))
-
-/*
- * These are the main single-value transfer routines. They
- * automatically use the right size if we just have the right pointer
- * type.
- *
- * This gets kind of ugly. We want to return _two_ values in
- * "get_user()" and yet we don't want to do any pointers, because that
- * is too much of a performance impact. Thus we have a few rather ugly
- * macros here, and hide all the uglyness from the user.
- *
- * Careful to not
- * (a) re-use the arguments for side effects (sizeof is ok)
- * (b) require any knowledge of processes at this stage
- */
-#define put_user(x,ptr) __put_user_check((x),(ptr),sizeof(*(ptr)))
-#define get_user(x,ptr) __get_user_check((x),(ptr),sizeof(*(ptr)))
-
-/*
- * The "__xxx" versions of the user access functions are versions that
- * do not verify the address space, that must have been done previously
- * with a separate "access_ok()" call (this is used when we do multiple
- * accesses to the same area of user memory).
- */
-#define __put_user(x,ptr) __put_user_nocheck((x),(ptr),sizeof(*(ptr)))
-#define __get_user(x,ptr) __get_user_nocheck((x),(ptr),sizeof(*(ptr)))
-
-
-extern long __put_user_bad(void);
-
-#define __put_user_nocheck(x,ptr,size) \
-({ \
- long __pu_err; \
- __put_user_size((x),(ptr),(size),__pu_err); \
- __pu_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_size(x,ptr,size,retval) \
-do { \
- int __cb; \
- retval = 0; \
- switch (size) { \
- case 1: __put_user_asm(x,ptr,retval,1,"s8i",__cb); break; \
- case 2: __put_user_asm(x,ptr,retval,2,"s16i",__cb); break; \
- case 4: __put_user_asm(x,ptr,retval,4,"s32i",__cb); break; \
- case 8: { \
- __typeof__(*ptr) __v64 = x; \
- retval = __copy_to_user(ptr,&__v64,8); \
- break; \
- } \
- default: __put_user_bad(); \
- } \
-} while (0)
-
-
-/*
- * Consider a case of a user single load/store would cause both an
- * unaligned exception and an MMU-related exception (unaligned
- * exceptions happen first):
- *
- * User code passes a bad variable ptr to a system call.
- * Kernel tries to access the variable.
- * Unaligned exception occurs.
- * Unaligned exception handler tries to make aligned accesses.
- * Double exception occurs for MMU-related cause (e.g., page not mapped).
- * do_page_fault() thinks the fault address belongs to the kernel, not the
- * user, and panics.
- *
- * The kernel currently prohibits user unaligned accesses. We use the
- * __check_align_* macros to check for unaligned addresses before
- * accessing user space so we don't crash the kernel. Both
- * __put_user_asm and __get_user_asm use these alignment macros, so
- * macro-specific labels such as 0f, 1f, %0, %2, and %3 must stay in
- * sync.
- */
-
-#define __check_align_1 ""
-
-#define __check_align_2 \
- " _bbci.l %3, 0, 1f \n" \
- " movi %0, %4 \n" \
- " _j 2f \n"
-
-#define __check_align_4 \
- " _bbsi.l %3, 0, 0f \n" \
- " _bbci.l %3, 1, 1f \n" \
- "0: movi %0, %4 \n" \
- " _j 2f \n"
-
-
-/*
- * We don't tell gcc that we are accessing memory, but this is OK
- * because we do not write to any memory gcc knows about, so there
- * are no aliasing issues.
- *
- * WARNING: If you modify this macro at all, verify that the
- * __check_align_* macros still work.
- */
-#define __put_user_asm(x, addr, err, align, insn, cb) \
- __asm__ __volatile__( \
- __check_align_##align \
- "1: "insn" %2, %3, 0 \n" \
- "2: \n" \
- " .section .fixup,\"ax\" \n" \
- " .align 4 \n" \
- "4: \n" \
- " .long 2b \n" \
- "5: \n" \
- " l32r %1, 4b \n" \
- " movi %0, %4 \n" \
- " jx %1 \n" \
- " .previous \n" \
- " .section __ex_table,\"a\" \n" \
- " .long 1b, 5b \n" \
- " .previous" \
- :"=r" (err), "=r" (cb) \
- :"r" ((int)(x)), "r" (addr), "i" (-EFAULT), "0" (err))
-
-#define __get_user_nocheck(x,ptr,size) \
-({ \
- long __gu_err, __gu_val; \
- __get_user_size(__gu_val,(ptr),(size),__gu_err); \
- (x) = (__typeof__(*(ptr)))__gu_val; \
- __gu_err; \
-})
-
-#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; \
-})
-
-extern long __get_user_bad(void);
-
-#define __get_user_size(x,ptr,size,retval) \
-do { \
- int __cb; \
- retval = 0; \
- switch (size) { \
- case 1: __get_user_asm(x,ptr,retval,1,"l8ui",__cb); break; \
- case 2: __get_user_asm(x,ptr,retval,2,"l16ui",__cb); break; \
- case 4: __get_user_asm(x,ptr,retval,4,"l32i",__cb); break; \
- case 8: retval = __copy_from_user(&x,ptr,8); break; \
- default: (x) = __get_user_bad(); \
- } \
-} while (0)
-
-
-/*
- * WARNING: If you modify this macro at all, verify that the
- * __check_align_* macros still work.
- */
-#define __get_user_asm(x, addr, err, align, insn, cb) \
- __asm__ __volatile__( \
- __check_align_##align \
- "1: "insn" %2, %3, 0 \n" \
- "2: \n" \
- " .section .fixup,\"ax\" \n" \
- " .align 4 \n" \
- "4: \n" \
- " .long 2b \n" \
- "5: \n" \
- " l32r %1, 4b \n" \
- " movi %2, 0 \n" \
- " movi %0, %4 \n" \
- " jx %1 \n" \
- " .previous \n" \
- " .section __ex_table,\"a\" \n" \
- " .long 1b, 5b \n" \
- " .previous" \
- :"=r" (err), "=r" (cb), "=r" (x) \
- :"r" (addr), "i" (-EFAULT), "0" (err))
-
-
-/*
- * Copy to/from user space
- */
-
-/*
- * We use a generic, arbitrary-sized copy subroutine. The Xtensa
- * architecture would cause heavy code bloat if we tried to inline
- * these functions and provide __constant_copy_* equivalents like the
- * i386 versions. __xtensa_copy_user is quite efficient. See the
- * .fixup section of __xtensa_copy_user for a discussion on the
- * X_zeroing equivalents for Xtensa.
- */
-
-extern unsigned __xtensa_copy_user(void *to, const void *from, unsigned n);
-#define __copy_user(to,from,size) __xtensa_copy_user(to,from,size)
-
-
-static inline unsigned long
-__generic_copy_from_user_nocheck(void *to, const void *from, unsigned long n)
-{
- return __copy_user(to,from,n);
-}
-
-static inline unsigned long
-__generic_copy_to_user_nocheck(void *to, const void *from, unsigned long n)
-{
- return __copy_user(to,from,n);
-}
-
-static inline unsigned long
-__generic_copy_to_user(void *to, const void *from, unsigned long n)
-{
- prefetch(from);
- if (access_ok(VERIFY_WRITE, to, n))
- return __copy_user(to,from,n);
- return n;
-}
-
-static inline unsigned long
-__generic_copy_from_user(void *to, const void *from, unsigned long n)
-{
- prefetchw(to);
- if (access_ok(VERIFY_READ, from, n))
- return __copy_user(to,from,n);
- else
- memset(to, 0, n);
- return n;
-}
-
-#define copy_to_user(to,from,n) __generic_copy_to_user((to),(from),(n))
-#define copy_from_user(to,from,n) __generic_copy_from_user((to),(from),(n))
-#define __copy_to_user(to,from,n) __generic_copy_to_user_nocheck((to),(from),(n))
-#define __copy_from_user(to,from,n) __generic_copy_from_user_nocheck((to),(from),(n))
-#define __copy_to_user_inatomic __copy_to_user
-#define __copy_from_user_inatomic __copy_from_user
-
-
-/*
- * We need to return the number of bytes not cleared. Our memset()
- * returns zero if a problem occurs while accessing user-space memory.
- * In that event, return no memory cleared. Otherwise, zero for
- * success.
- */
-
-static inline unsigned long
-__xtensa_clear_user(void *addr, unsigned long size)
-{
- if ( ! memset(addr, 0, size) )
- return size;
- return 0;
-}
-
-static inline unsigned long
-clear_user(void *addr, unsigned long size)
-{
- if (access_ok(VERIFY_WRITE, addr, size))
- return __xtensa_clear_user(addr, size);
- return size ? -EFAULT : 0;
-}
-
-#define __clear_user __xtensa_clear_user
-
-
-extern long __strncpy_user(char *, const char *, long);
-#define __strncpy_from_user __strncpy_user
-
-static inline long
-strncpy_from_user(char *dst, const char *src, long count)
-{
- if (access_ok(VERIFY_READ, src, 1))
- return __strncpy_from_user(dst, src, count);
- return -EFAULT;
-}
-
-
-#define strlen_user(str) strnlen_user((str), TASK_SIZE - 1)
-
-/*
- * Return the size of a string (including the ending 0!)
- */
-extern long __strnlen_user(const char *, long);
-
-static inline long strnlen_user(const char *str, long len)
-{
- unsigned long top = __kernel_ok ? ~0UL : TASK_SIZE - 1;
-
- if ((unsigned long)str > top)
- return 0;
- return __strnlen_user(str, len);
-}
-
-
-struct exception_table_entry
-{
- unsigned long insn, fixup;
-};
-
-/* Returns 0 if exception not found and fixup.unit otherwise. */
-
-extern unsigned long search_exception_table(unsigned long addr);
-extern void sort_exception_table(void);
-
-/* Returns the new pc */
-#define fixup_exception(map_reg, fixup_unit, pc) \
-({ \
- fixup_unit; \
-})
-
-#endif /* __ASSEMBLY__ */
-#endif /* _XTENSA_UACCESS_H */