Re: [Xen-devel] [PATCH 02/10] Move PAGE_SHIFT to memmap.h

[Ian Campbell <Ian.Campbell@xxxxxxxxxx>]

On Wed, 2011-08-24 at 18:51 +0100, Konrad Rzeszutek Wilk wrote:
> On Fri, Aug 19, 2011 at 01:03:19AM +0900, Daniel Castro wrote:
> > PAGE_SHIFT is used by both Virtio and Xen as a contant when moving
> > addresses from guest space to machine space, in order to have a
> > single definition PAGE_SHIFT has been moved to memmap.h. This has
> > no impact on neither virtio or xen.
> > 
> > Signed-off-by: Daniel Castro <evil.dani@xxxxxxxxx>
> > ---
> >  src/memmap.h      |    2 ++
> >  src/virtio-ring.h |    2 +-
> >  2 files changed, 3 insertions(+), 1 deletions(-)
> > 
> > diff --git a/src/memmap.h b/src/memmap.h
> > index 01c7ddb..8674168 100644
> > --- a/src/memmap.h
> > +++ b/src/memmap.h
> > @@ -21,6 +21,8 @@ void memmap_finalize(void);
> >  
> >  // A typical OS page size
> >  #define PAGE_SIZE 4096
> > +//Used by Virtio and Xen
> > +#define PAGE_SHIFT 12
> 
> So aren't those two files also used on other architectures - say
> PPC64 which have a different page size - 64K. Isn't there some other
> defines for this? Or are the patches for that not present anywhere yet?

This patch is against SeaBIOS, which is a reimplementation of the legacy
PC BIOS -- I don't think you would want it on anything other than x86
and AFAICT SeaBIOS doesn't have any support for doing so.

Ian.

> 
> >  
> >  // e820 map storage (defined in system.c)
> >  extern struct e820entry e820_list[];
> > diff --git a/src/virtio-ring.h b/src/virtio-ring.h
> > index b7a7aaf..fd30778 100644
> > --- a/src/virtio-ring.h
> > +++ b/src/virtio-ring.h
> > @@ -4,7 +4,7 @@
> >  #include "types.h" // u64
> >  #include "memmap.h" // PAGE_SIZE
> >  
> > -#define PAGE_SHIFT 12
> > +
> >  #define PAGE_MASK  (PAGE_SIZE-1)
> >  
> >  #define virt_to_phys(v) (unsigned long)(v)
> > -- 
> > 1.7.4.1
> > 
> > 
> > _______________________________________________
> > Xen-devel mailing list
> > Xen-devel@xxxxxxxxxxxxxxxxxxx
> > http://lists.xensource.com/xen-devel
> 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@xxxxxxxxxxxxxxxxxxx
> http://lists.xensource.com/xen-devel



_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel