Re: [PATCH] mach_defpager: Fix external objects interface

[Sergio Lopez]

El Wed, 19 May 2010 10:17:00 +0200
<olafBuddenhagen@gmx.net> escribió:
> On Tue, May 18, 2010 at 04:19:10PM +0200, Sergio Lopez wrote:
> 
> > This patch fixes external objects interface in mach_defpager
> > (current default pager in Hurd), so it can be used as backing store
> > by other translators (like tmpfs).
> 
> I don't know enough about this code to actually understand the
> changes. However, on a quick glance, there seem to be several
> unrelated fixes in this patch?... Please split them into separate
> patches; and add a short explanation to each.
> 

OK, here we go:

  - 01defpager-mutex.patch: Properly unlock the mutex before returning
    NO_BLOCK in pager_read_offset.

  - 02defpager-extread.patch: Add an "external" attribute to
    dstruct structure. In default_read, if the object is external,
    resolve a read request with a zero filled page.

  - 03defpager-synclock.patch: Remove user reference count logic, to
    avoid setting an arbitrary limit to the number of requests
    processed by an object. Don't request completion notification for
    m_o_lock_request. I think is worth noting that the original problem
    which makes default_pager get stuck waiting for a seqno that never
    arrives in S_default_pager_object_set_size, was just that
    reply_port and seqno arguments were in wrong order.

  - 04defpager-objectsize.patch: In S_default_pager_object_create,
    reject values for "size" other than "vm_page_size", since internal
    logic doesn't properly support it (though object size limit can be
    increased by sucesive calls to S_default_pager_set_size).

04defpager-objectsize.patch
Description: Text Data

03defpager-synclock.patch
Description: Text Data

01defpager-mutex.patch
Description: Text Data

02defpager-extread.patch
Description: Text Data