Does mmap fit a page or part of a page?

Question

Am I confused, mmapis it allocating a whole page of memory (regardless of the specified size), or is it just allocating the required size? Indeed, I am curious what will happen in subsequent calls to mmap- if the second call selects a new page (even if both calls use the sum of the page size) or it selects a block adjacent to the previous call

The same for mprotect- does it protect the entire page or only the specified part?

Answer 1

If the length argument is not a multiple of the page size, it will be rounded to the size of the page.

, : yes mmap() .

mprotect(), :

mprotect() () [addr, + LEN-1]. addr .

Answer 2

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: POSIX