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			102 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			102 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* Copyright (C) 1999,2000,2001,2002,2006,2010 Free Software Foundation, Inc.
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|    This file is part of the GNU C Library.
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|    Contributed by Jakub Jelinek <jakub@redhat.com>, 1999.
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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 <unistd.h>
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| #include <sys/mman.h>
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| 
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| #include <sysdep.h>
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| #include <sys/syscall.h>
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| #include <bp-checks.h>
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| 
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| #include <kernel-features.h>
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| 
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| #ifdef __NR_mmap2
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| 
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| /* This is always 12, even on architectures where PAGE_SHIFT != 12.  */
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| # if MMAP2_PAGE_SHIFT == -1
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| static int page_shift;
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| # else
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| #  ifndef MMAP2_PAGE_SHIFT
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| #   define MMAP2_PAGE_SHIFT 12
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| #  endif
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| # define page_shift MMAP2_PAGE_SHIFT
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| # endif
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| 
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| # ifndef __ASSUME_MMAP2_SYSCALL
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| static int have_no_mmap2;
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| # endif
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| #endif
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| 
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| 
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| void *
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| __mmap64 (void *addr, size_t len, int prot, int flags, int fd, off64_t offset)
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| {
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| #ifdef __NR_mmap2
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| # if MMAP2_PAGE_SHIFT == -1
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|   if (page_shift == 0)
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|     {
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|       int page_size = getpagesize ();
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|       while ((1 << ++page_shift) != page_size)
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| 	;
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|     }
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| # endif
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|   if (offset & ((1 << page_shift) - 1))
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|     {
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|       __set_errno (EINVAL);
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|       return MAP_FAILED;
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|     }
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| # ifndef __ASSUME_MMAP2_SYSCALL
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|   if (! have_no_mmap2)
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| # endif
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|     {
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| # ifndef __ASSUME_MMAP2_SYSCALL
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|       int saved_errno = errno;
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| # endif
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|       void *result;
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|       __ptrvalue (result) = (void *__unbounded)
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| 	INLINE_SYSCALL (mmap2, 6, __ptrvalue (addr),
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| 			len, prot, flags, fd,
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| 			(off_t) (offset >> MMAP2_PAGE_SHIFT));
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| # if __BOUNDED_POINTERS__
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|       __ptrlow (result) = __ptrvalue (result);
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|       __ptrhigh (result) = __ptrvalue (result) + len;
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| # endif
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| # ifndef __ASSUME_MMAP2_SYSCALL
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|       if (result != MAP_FAILED || errno != ENOSYS)
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| # endif
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| 	return result;
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| 
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| # ifndef __ASSUME_MMAP2_SYSCALL
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|       __set_errno (saved_errno);
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|       have_no_mmap2 = 1;
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| # endif
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|     }
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| #endif
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| #ifndef __ASSUME_MMAP2_SYSCALL
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|   if (offset != (off_t) offset || (offset + len) != (off_t) (offset + len))
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|     {
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|       __set_errno (EINVAL);
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|       return MAP_FAILED;
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|     }
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| 
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|   return __mmap (addr, len, prot, flags, fd, (off_t) offset);
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| #endif
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| }
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| weak_alias (__mmap64, mmap64)
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