Commit Graph

5 Commits

Author SHA1 Message Date
Paul Mackerras
bf72aeba2f powerpc: Use 64k pages without needing cache-inhibited large pages
Some POWER5+ machines can do 64k hardware pages for normal memory but
not for cache-inhibited pages.  This patch lets us use 64k hardware
pages for most user processes on such machines (assuming the kernel
has been configured with CONFIG_PPC_64K_PAGES=y).  User processes
start out using 64k pages and get switched to 4k pages if they use any
non-cacheable mappings.

With this, we use 64k pages for the vmalloc region and 4k pages for
the imalloc region.  If anything creates a non-cacheable mapping in
the vmalloc region, the vmalloc region will get switched to 4k pages.
I don't know of any driver other than the DRM that would do this,
though, and these machines don't have AGP.

When a region gets switched from 64k pages to 4k pages, we do not have
to clear out all the 64k HPTEs from the hash table immediately.  We
use the _PAGE_COMBO bit in the Linux PTE to indicate whether the page
was hashed in as a 64k page or a set of 4k pages.  If hash_page is
trying to insert a 4k page for a Linux PTE and it sees that it has
already been inserted as a 64k page, it first invalidates the 64k HPTE
before inserting the 4k HPTE.  The hash invalidation routines also use
the _PAGE_COMBO bit, to determine whether to look for a 64k HPTE or a
set of 4k HPTEs to remove.  With those two changes, we can tolerate a
mix of 4k and 64k HPTEs in the hash table, and they will all get
removed when the address space is torn down.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-15 10:45:18 +10:00
Paul Mackerras
5164501794 Merge ../linux-2.6 2006-03-09 14:32:05 +11:00
David Gibson
141aa59b53 [PATCH] powerpc: Fix incorrect pud_ERROR() message
The powerpc pud_ERROR() function misleadingly prints a message
indicating a pmd error.  This patch fixes it.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-03-03 22:00:52 +11:00
David Gibson
20f4eb3e50 [PATCH] powerpc: Fixup for STRICT_MM_TYPECHECKS
Currently ARCH=powerpc will not compile when STRICT_MM_TYPECHECKS is
turned on and CONFIG_64K_PAGES is turned off.  This corrects the
problem.

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-02-24 14:05:58 +11:00
Paul Mackerras
047ea78465 powerpc: Trivially merge several headers from asm-ppc64 to asm-powerpc
For these, I have just done the lame-o merge where the file ends up
looking like:

	#ifndef CONFIG_PPC64
	#include <asm-ppc/foo.h>
	#else
	... contents from asm-ppc64/foo.h
	#endif

so nothing has changed, really, except that we reduce include/asm-ppc64
a bit more.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-19 20:17:32 +11:00