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/* Copyright (C) 2000 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <features.h>
#define _ERRNO_H
#include <bits/errno.h>
#include <sys/syscall.h>
#include <bits/arm_asm.h>
#if defined __UCLIBC_HAS_LFS__ && defined __NR_mmap2
/* The mmap2 system call takes six arguments, all in registers. */
.text
.global mmap64
.type mmap64,%function
.align 2
#ifdef __ARM_EABI__
#if defined(THUMB1_ONLY)
.thumb_func
mmap64:
#ifdef __ARMEB__
/* Offsets are after pushing 3 words. */
# define LOW_OFFSET 12 + 8 + 4
# define HIGH_OFFSET 12 + 8 + 0
#else
# define LOW_OFFSET 12 + 8 + 0
# define HIGH_OFFSET 12 + 8 + 4
#endif
push {r4, r5, r6}
ldr r6, [sp, $LOW_OFFSET]
ldr r5, [sp, $HIGH_OFFSET]
lsl r4, r6, #20 @ check that offset is page-aligned
bne .Linval
lsr r4, r5, #12 @ check for overflow
bne .Linval
@ compose page offset
lsr r6, r6, #12
lsl r5, r5, #20
orr r5, r5, r6
ldr r4, [sp, #8] @ load fd
DO_CALL (mmap2)
ldr r1, =0xfffff000
cmp r0, r1
bcs .Lerror
bx lr
.Linval:
ldr r0, =-EINVAL
pop {r4, r5, r6}
.Lerror:
push {r3, lr}
bl __syscall_error
POP_RET
.pool
#else /* !THUMB1_ONLY */
mmap64:
#ifdef __ARMEB__
# define LOW_OFFSET 8 + 4
/* The initial + 4 is for the stack postdecrement. */
# define HIGH_OFFSET 4 + 8 + 0
#else
# define LOW_OFFSET 8 + 0
# define HIGH_OFFSET 4 + 8 + 4
#endif
ldr ip, [sp, $LOW_OFFSET]
str r5, [sp, #-4]!
ldr r5, [sp, $HIGH_OFFSET]
str r4, [sp, #-4]!
movs r4, ip, lsl $20 @ check that offset is page-aligned
mov ip, ip, lsr $12
IT(t, eq)
moveqs r4, r5, lsr $12 @ check for overflow
bne .Linval
ldr r4, [sp, $8] @ load fd
orr r5, ip, r5, lsl $20 @ compose page offset
DO_CALL (mmap2)
cmn r0, $4096
ldmfd sp!, {r4, r5}
IT(t, cc)
#if defined(__USE_BX__)
bxcc lr
#else
movcc pc, lr
#endif
b __syscall_error
.Linval:
mov r0, $-EINVAL
ldmfd sp!, {r4, r5}
b __syscall_error
#endif
#else /* !__ARM_EABI__ */
mmap64:
stmfd sp!, {r4, r5, lr}
ldr r5, [sp, $16]
ldr r4, [sp, $12]
movs ip, r5, lsl $20 @ check that offset is page-aligned
bne .Linval
ldr ip, [sp, $20]
mov r5, r5, lsr $12
orr r5, r5, ip, lsl $20 @ compose page offset
movs ip, ip, lsr $12
bne .Linval @ check for overflow
mov ip, r0
DO_CALL (mmap2)
cmn r0, $4096
ldmccfd sp!, {r4, r5, pc}
cmn r0, $ENOSYS
ldmnefd sp!, {r4, r5, lr}
bne __error
/* The current kernel does not support mmap2. Fall back to plain
mmap if the offset is small enough. */
ldr r5, [sp, $20]
mov r0, ip @ first arg was clobbered
teq r5, $0
ldmeqfd sp!, {r4, r5, lr}
beq HIDDEN_JUMPTARGET(mmap)
.Linval:
mov r0, $-EINVAL
ldmfd sp!, {r4, r5, lr}
b __error
__error:
b __syscall_error
#endif
.size mmap64,.-mmap64
#endif
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