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	As noted by c1f0601389, previous posix_fadvise consolidation
broke on mips o32.  As stated in commit message, MIPS o32 only defines
__NR_fadvise64 and it is behaves like __NR_fadvise64_64.
This patches consolidates both ARM and mips o32 version by fixing
the ARM used option (__NR_fadvise64_64 withouth the alignment required
by abi) and added another option, __ASSUME_FADVISE64_AS_64_64,
which is used on mips o32.
When this option is used, posix_fadvise will use __NR_fadvise64_64
behavior (by defining or not __ASSUME_FADVISE64_64_6ARG).  For
mips, if __NR_fadvise64_64 is not defined, __NR_fadvise will be used.
I also updated the posix_fadvise comments to explain better the
different kernel abi used in the supported architectures.
I checked with a mips o32 and verified that posix_fadvise.o is
indeed using 7 argument syscall with the expected argument position.
I also checked on i686-linux-gnu and arm-gnu-eabihf.
	* sysdeps/unix/sysv/linux/arm/posix_fadvise.c: Remove file.
	* sysdeps/unix/sysv/linux/mips/mips32/posix_fadvise.c: Likewise.
	* sysdeps/unix/sysv/linux/mips/kernel-features.h
	(__ASSUME_FADVISE64_AS_64_64): Define.
	* sysdeps/unix/sysv/linux/posix_fadvise.c [__NR_fadvise64]: Add
	!defined __ASSUME_FADVISE64_AS_64_64 to use syscall issue.
	[!__NR_fadvise64 && __ASSUME_FADVISE64_64_6ARG]: Remove
	__ALIGNMENT_ARG usage.
	[!__NR_fadvise64 && !__ASSUME_FADVISE64_64_6ARG]: Define
	__NR_fadvise64_64 if it is not defined.
		
	
		
			
				
	
	
		
			75 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			75 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* Copyright (C) 2003-2017 Free Software Foundation, Inc.
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|    This file is part of the GNU C Library.
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| 
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|    The GNU C Library is free software; you can redistribute it and/or
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|    modify it under the terms of the GNU Lesser General Public
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|    License as published by the Free Software Foundation; either
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|    version 2.1 of the License, or (at your option) any later version.
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| 
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|    The GNU C Library is distributed in the hope that it will be useful,
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|    but WITHOUT ANY WARRANTY; without even the implied warranty of
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|    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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|    Lesser General Public License for more details.
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| 
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|    You should have received a copy of the GNU Lesser General Public
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|    License along with the GNU C Library; if not, see
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|    <http://www.gnu.org/licenses/>.  */
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| 
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| #include <errno.h>
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| #include <fcntl.h>
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| #include <sysdep.h>
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| 
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| /* Advice the system about the expected behaviour of the application with
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|    respect to the file associated with FD.  */
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| 
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| #ifndef __OFF_T_MATCHES_OFF64_T
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| 
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| /* Default implementation will use __NR_fadvise64 with expected argument
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|    positions (for instance i386 and powerpc32 that uses __ALIGNMENT_ARG).
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| 
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|    Second option will be used by arm which define __NR_arm_fadvise64_64
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|    (redefined to __NR_fadvise64_64 in kernel-features.h) that behaves as
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|    __NR_fadvise64_64 (without the aligment argument required for the ABI).
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| 
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|    Third option will be used by both tile 32-bits and mips o32.  Tile
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|    will set __ASSUME_FADVISE64_64_NO_ALIGN to issue a 6 argument syscall,
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|    while mips will use a 7 argument one with __NR_fadvise64.
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| 
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|    s390 implements fadvice64_64 using a specific struct with arguments
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|    packed inside.  This is the only implementation handled in arch-specific
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|    code.  */
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| 
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| int
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| posix_fadvise (int fd, off_t offset, off_t len, int advise)
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| {
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|   INTERNAL_SYSCALL_DECL (err);
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| # if defined (__NR_fadvise64) && !defined (__ASSUME_FADVISE64_AS_64_64)
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|   int ret = INTERNAL_SYSCALL_CALL (fadvise64, err, fd,
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| 				   __ALIGNMENT_ARG SYSCALL_LL (offset),
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| 				   len, advise);
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| # else
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| #  ifdef __ASSUME_FADVISE64_64_6ARG
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|   int ret = INTERNAL_SYSCALL_CALL (fadvise64_64, err, fd, advise,
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| 				   SYSCALL_LL (offset), SYSCALL_LL (len));
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| #  else
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| 
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| #   ifdef __ASSUME_FADVISE64_64_NO_ALIGN
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| #    undef __ALIGNMENT_ARG
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| #    define __ALIGNMENT_ARG
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| #   endif
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| 
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| #   ifndef __NR_fadvise64_64
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| #    define __NR_fadvise64_64 __NR_fadvise64
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| #   endif
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| 
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|   int ret = INTERNAL_SYSCALL_CALL (fadvise64_64, err, fd,
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| 				   __ALIGNMENT_ARG SYSCALL_LL (offset),
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| 				   SYSCALL_LL (len), advise);
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| #  endif
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| # endif
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|   if (INTERNAL_SYSCALL_ERROR_P (ret, err))
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|     return INTERNAL_SYSCALL_ERRNO (ret, err);
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|   return 0;
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| }
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| #endif /* __OFF_T_MATCHES_OFF64_T  */
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