Re: Re: [Xen-changelog] [linux-2.6.18-xen] Add "#ifdef ARCH_HAS_DEV_MEM" to archtecture specific file_operations.

[Jun Kamada <kama@jp.fujitsu.com>]

Keir-san,

On Wed, 11 Jul 2007 11:00:37 +0100
Keir Fraser <keir@xensource.com> wrote:
> The case of building drivers/xen/char/mem.c, yet not defining
> ARCH_HAS_DEV_MEM, does not seem useful. Who will pick up and use the
> mem_fops defined by drivers/xen/char/mem.c?
> 
> At the very least this seems abusive of ARCH_HAS_DEV_MEM, and you might be
> better off defining a different macro name? But I think you need to explain
> to us what it is you're actually trying to achieve.

I would like to deal with the drivers/xen/char/mem.c as follows. How do
you think about it? It will cause any problem?

- I will post a patch, which removes definition of ARCH_HAS_DEV_MEM, to
  xen-ia64-devel later.
- If needed, I will post a revert patch of 
  "xen-ia64-devel.hg c/s 12544:395aa5609e6d". (Creating the revert patch
  may be difficult...)

> better off defining a different macro name? But I think you need to explain
> to us what it is you're actually trying to achieve.

We would like to map machine address to guest physical address at PCI
initialization phase but at mmap system call in order to support Xwindow.
The patch I posted is one of the patch which disables mapping process at
mmap system call.

Best regards,

-----
Jun Kamada
Linux Technology Development Div.
Server Systems Unit
Fujitsu Ltd.
kama@jp.fujitsu.com