From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mtagate5.de.ibm.com ([195.212.29.154]:25886 "EHLO mtagate5.de.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752663AbXJYSTD (ORCPT ); Thu, 25 Oct 2007 14:19:03 -0400 Message-Id: <20071025181520.880272069@de.ibm.com> Date: Thu, 25 Oct 2007 20:15:20 +0200 From: Martin Schwidefsky Subject: [patch 0/6] s390 page tables on steroids .. Sender: linux-arch-owner@vger.kernel.org To: linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-s390@vger.kernel.org Cc: borntraeger@de.ibm.com, benh@kernel.crashing.org List-ID: Greetings, this patch series of six patches contains three mm related changes for the s390 architecture: i) 1K/2K page tables. With this patch set the cheating with the pmd_t on s390 stops. So far a pmd contained 2/4 pointers instead of just one which would be correct from an architectural stand point. The Trouble with this is that it requires two common code changes to make sub-page page tables possible. This features is an important requirement for the kvm support on s390. ii) Support for 4 levels of page tables. The address space limit for 64 bit processes is now 2^53. That should be enough for anyone ? iii) Support for different number of page table levels. The limit of 2^53 is nice but it slows down the tlb lookup that now has to walk 4 instead of 3 levels. Patch #5 make the number of page table levels dependent on the highest address a process is using. If an mmap is done that raises the limit to the next level, the page table gets another level. A downgrade is only done at process start, so that 31 bit processes get a two level page table. A normal 64 bit process starts with three levels. The first three patches in the series contain the common code changes that are needed to get all of this done. I did my best to find all the place in the different architectures that need to be updated after the common code changed. Please let me know if you find a place I missed. The patches are against Linus's git tree. -- blue skies, Martin. "Reality continues to ruin my life." - Calvin.