glibc/sysdeps/unix/sysv/linux/arm/mmap64.S
Ulrich Drepper e3aaaa2732 Update.
2000-01-03  Philip Blundell  <philb@gnu.org>

	* sysdeps/unix/sysv/linux/kernel-features.h (__ASSUME_MMAP2_SYSCALL,
	__ASSUME_TRUNCATE64_SYSCALL, __ASSUME_STAT64_SYSCALL): Define on
	ARM for kernels >= 2.3.35.

2000-01-03  Philip Blundell  <philb@gnu.org>

	* sysdeps/unix/sysv/linux/arm/mmap.S: Remove mmap64 alias.
	Optimise error handling a little.
	* sysdeps/unix/sysv/linux/arm/mmap64.S: New file.
2000-01-03 23:22:35 +00:00

67 lines
2.0 KiB
ArmAsm

/* 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 Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <sysdep.h>
#define EINVAL 22
/* The mmap2 system call takes six arguments, all in registers. */
.text
ENTRY (__mmap64)
#ifdef __NR_mmap2
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
swi SYS_ify (mmap2)
cmn r0, $4096
LOADREGS(ccfd, sp!, {r4, r5, pc})
teq r0, $-ENOSYS
ldmnefd sp!, {r4, r5, lr}
bne PLTJMP(syscall_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 PLTJMP(__mmap)
.Linval:
mov r0, $-EINVAL
ldmfd sp!, {r4, r5, lr}
b PLTJMP(syscall_error)
#else
/* The kernel headers do not support mmap2. Fall back to plain
mmap if the offset is small enough. */
ldr ip, [sp, $8]
teq ip, $0
beq PLTJMP(__mmap)
mov r0, $-EINVAL
b PLTJMP(syscall_error)
#endif
PSEUDO_END (__mmap64)
weak_alias (__mmap64, mmap64)