[fuse-devel] fuse mmap( ) size limitations?

[Xiangyong (S. O. <ou...@cs...>]

Hi all,

Are there any limits on mmap( ) size that fuse supports?

I have a very simple fuse-based filesystem that's backed by an ext3.   It
does nothing but converts "fuse_operations" into corresponding ext3 file
calls.  I opened the a file and truncated it to be certain size X ( 100GB
for example ).   Then I mmap() the file into a virtual address that is of
the same length X.

mmap() succeeded for X<=12GB.  If X>12GB  mmap() failed.


Why I cannot mmap a larger space?  I'm running 2.6.30.10,  fuse library
2.8.1.  My machine has 6GB memory.   Thanks!




-Xiangyong Ouyang