Re: Writing out a (file) mmapped page

[Coywolf Qi Hunt <coywolf@gmail.com>]

On 6/13/05, Martin Jambor <jamborm@gmail.com> wrote:
> Hi,
> 
> I have spent a few hours trying to find out how dirty mmapped pages
> are written out in filesystems using the "generic" functions but so
> far I have not been successful. The main thing that escapes me is the
> following:
> 
> block_write_full_page() writes out only buffers marked dirty or whole
> page when there are no buffers associated with it. Where in kernel are
> buffers either marked dirty or stripped off a mmaped page when the
> page itself becomes dirty?  I would be very grateful for a pointer to
> the source, possibly accompanied by a brief explanation of how it gets
> called.
> 
> One comment in buffer.c suggests aops->prepare_write is called by a
> pagefault handler for mmaped pages but I found no such call (using
> cscope).

generic_file_buffered_write() calls a_ops->prepare_write().

-- 
Coywolf Qi Hunt
http://ahbl.org/~coywolf/