17 lines
705 B
C
17 lines
705 B
C
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/* As default architectures with sizeof (off_t) < sizeof (off64_t) the mmap is
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implemented with __SYS_mmap2 syscall and the offset is represented in
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multiples of page size. For offset larger than
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'1 << (page_shift + 8 * sizeof (off_t))' (that is, 1<<44 on system with
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page size of 4096 bytes) the system call silently truncates the offset.
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For this case, glibc mmap implementation returns EINVAL. */
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/* Return the maximum value expected as offset argument in mmap64 call. */
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static inline uint64_t
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mmap64_maximum_offset (long int page_shift)
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{
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if (sizeof (off_t) < sizeof (off64_t))
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return (UINT64_C(1) << (page_shift + (8 * sizeof (off_t)))) - 1;
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else
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return UINT64_MAX;
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}
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