forked from Minki/linux
86 lines
2.7 KiB
C
86 lines
2.7 KiB
C
/*
|
|
* Copyright 2011 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.
|
|
*
|
|
* Do memcpy(), but trap and return "n" when a load or store faults.
|
|
*
|
|
* Note: this idiom only works when memcpy() compiles to a leaf function.
|
|
* Here leaf function not only means it does not have calls, but also
|
|
* requires no stack operations (sp, stack frame pointer) and no
|
|
* use of callee-saved registers, else "jrp lr" will be incorrect since
|
|
* unwinding stack frame is bypassed. Since memcpy() is not complex so
|
|
* these conditions are satisfied here, but we need to be careful when
|
|
* modifying this file. This is not a clean solution but is the best
|
|
* one so far.
|
|
*
|
|
* Also note that we are capturing "n" from the containing scope here.
|
|
*/
|
|
|
|
#define _ST(p, inst, v) \
|
|
({ \
|
|
asm("1: " #inst " %0, %1;" \
|
|
".pushsection .coldtext,\"ax\";" \
|
|
"2: { move r0, %2; jrp lr };" \
|
|
".section __ex_table,\"a\";" \
|
|
".align 8;" \
|
|
".quad 1b, 2b;" \
|
|
".popsection" \
|
|
: "=m" (*(p)) : "r" (v), "r" (n)); \
|
|
})
|
|
|
|
#define _LD(p, inst) \
|
|
({ \
|
|
unsigned long __v; \
|
|
asm("1: " #inst " %0, %1;" \
|
|
".pushsection .coldtext,\"ax\";" \
|
|
"2: { move r0, %2; jrp lr };" \
|
|
".section __ex_table,\"a\";" \
|
|
".align 8;" \
|
|
".quad 1b, 2b;" \
|
|
".popsection" \
|
|
: "=r" (__v) : "m" (*(p)), "r" (n)); \
|
|
__v; \
|
|
})
|
|
|
|
#define USERCOPY_FUNC raw_copy_to_user
|
|
#define ST1(p, v) _ST((p), st1, (v))
|
|
#define ST2(p, v) _ST((p), st2, (v))
|
|
#define ST4(p, v) _ST((p), st4, (v))
|
|
#define ST8(p, v) _ST((p), st, (v))
|
|
#define LD1 LD
|
|
#define LD2 LD
|
|
#define LD4 LD
|
|
#define LD8 LD
|
|
#include "memcpy_64.c"
|
|
|
|
#define USERCOPY_FUNC raw_copy_from_user
|
|
#define ST1 ST
|
|
#define ST2 ST
|
|
#define ST4 ST
|
|
#define ST8 ST
|
|
#define LD1(p) _LD((p), ld1u)
|
|
#define LD2(p) _LD((p), ld2u)
|
|
#define LD4(p) _LD((p), ld4u)
|
|
#define LD8(p) _LD((p), ld)
|
|
#include "memcpy_64.c"
|
|
|
|
#define USERCOPY_FUNC raw_copy_in_user
|
|
#define ST1(p, v) _ST((p), st1, (v))
|
|
#define ST2(p, v) _ST((p), st2, (v))
|
|
#define ST4(p, v) _ST((p), st4, (v))
|
|
#define ST8(p, v) _ST((p), st, (v))
|
|
#define LD1(p) _LD((p), ld1u)
|
|
#define LD2(p) _LD((p), ld2u)
|
|
#define LD4(p) _LD((p), ld4u)
|
|
#define LD8(p) _LD((p), ld)
|
|
#include "memcpy_64.c"
|