Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753278AbYJ0Jjn (ORCPT ); Mon, 27 Oct 2008 05:39:43 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752113AbYJ0Jjd (ORCPT ); Mon, 27 Oct 2008 05:39:33 -0400 Received: from mtagate4.de.ibm.com ([195.212.29.153]:53518 "EHLO mtagate4.de.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750965AbYJ0Jjc (ORCPT ); Mon, 27 Oct 2008 05:39:32 -0400 To: Jeff Garzik Subject: [PATCH] ehea: Add hugepage detection From: Thomas Klein Cc: Christoph Raisch , Hannes Hering , "Jan-Bernd Themann" , "linux-kernel" , "linux-ppc" , "netdev" , badari@us.ibm.com, haveblue@us.ibm.com, tollefso@us.ibm.com Date: Mon, 27 Oct 2008 10:38:46 +0100 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200810271038.46825.tklein@de.ibm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4603 Lines: 127 All kernel memory which is used for kernel/hardware data transfer must be registered with firmware using "memory regions". 16GB hugepages may not be part of a memory region due to firmware restrictions. This patch modifies the walk_memory_resource callback fn to filter hugepages and add only standard memory to the busmap which is later on used for MR registration. Signed-off-by: Thomas Klein --- This reworked patch accounts for comments I got. It's based on davem's net-2.6.git. diff -Nurp -X dontdiff linux-2.6.27/drivers/net/ehea/ehea.h patched_kernel/drivers/net/ehea/ehea.h --- linux-2.6.27/drivers/net/ehea/ehea.h 2008-10-24 09:29:19.000000000 +0200 +++ patched_kernel/drivers/net/ehea/ehea.h 2008-10-27 09:27:46.000000000 +0100 @@ -40,7 +40,7 @@ #include #define DRV_NAME "ehea" -#define DRV_VERSION "EHEA_0094" +#define DRV_VERSION "EHEA_0095" /* eHEA capability flags */ #define DLPAR_PORT_ADD_REM 1 diff -Nurp -X dontdiff linux-2.6.27/drivers/net/ehea/ehea_qmr.c patched_kernel/drivers/net/ehea/ehea_qmr.c --- linux-2.6.27/drivers/net/ehea/ehea_qmr.c 2008-10-24 09:29:19.000000000 +0200 +++ patched_kernel/drivers/net/ehea/ehea_qmr.c 2008-10-27 09:27:46.000000000 +0100 @@ -632,10 +632,13 @@ static void ehea_rebuild_busmap(void) } } -static int ehea_update_busmap(unsigned long pfn, unsigned long pgnum, int add) +static int ehea_update_busmap(unsigned long pfn, unsigned long nr_pages, int add) { unsigned long i, start_section, end_section; + if (!nr_pages) + return 0; + if (!ehea_bmap) { ehea_bmap = kzalloc(sizeof(struct ehea_bmap), GFP_KERNEL); if (!ehea_bmap) @@ -643,7 +646,7 @@ static int ehea_update_busmap(unsigned l } start_section = (pfn * PAGE_SIZE) / EHEA_SECTSIZE; - end_section = start_section + ((pgnum * PAGE_SIZE) / EHEA_SECTSIZE); + end_section = start_section + ((nr_pages * PAGE_SIZE) / EHEA_SECTSIZE); /* Mark entries as valid or invalid only; address is assigned later */ for (i = start_section; i < end_section; i++) { u64 flag; @@ -692,10 +695,54 @@ int ehea_rem_sect_bmap(unsigned long pfn return ret; } -static int ehea_create_busmap_callback(unsigned long pfn, - unsigned long nr_pages, void *arg) +static int ehea_is_hugepage(unsigned long pfn) +{ + int page_order; + + if (pfn & EHEA_HUGEPAGE_PFN_MASK) + return 0; + + page_order = compound_order(pfn_to_page(pfn)); + if (page_order + PAGE_SHIFT != EHEA_HUGEPAGESHIFT) + return 0; + + return 1; +} + +static int ehea_create_busmap_callback(unsigned long initial_pfn, + unsigned long total_nr_pages, void *arg) { - return ehea_update_busmap(pfn, nr_pages, EHEA_BUSMAP_ADD_SECT); + int ret; + unsigned long pfn, start_pfn, end_pfn, nr_pages; + + if ((total_nr_pages * PAGE_SIZE) < EHEA_HUGEPAGE_SIZE) + return ehea_update_busmap(initial_pfn, total_nr_pages, + EHEA_BUSMAP_ADD_SECT); + + /* Given chunk is >= 16GB -> check for hugepages */ + start_pfn = initial_pfn; + end_pfn = initial_pfn + total_nr_pages; + pfn = start_pfn; + + while (pfn < end_pfn) { + if (ehea_is_hugepage(pfn)) { + /* Add mem found in front of the hugepage */ + nr_pages = pfn - start_pfn; + ret = ehea_update_busmap(start_pfn, nr_pages, + EHEA_BUSMAP_ADD_SECT); + if (ret) + return ret; + + /* Skip the hugepage */ + pfn += (EHEA_HUGEPAGE_SIZE / PAGE_SIZE); + start_pfn = pfn; + } else + pfn += (EHEA_SECTSIZE / PAGE_SIZE); + } + + /* Add mem found behind the hugepage(s) */ + nr_pages = pfn - start_pfn; + return ehea_update_busmap(start_pfn, nr_pages, EHEA_BUSMAP_ADD_SECT); } int ehea_create_busmap(void) diff -Nurp -X dontdiff linux-2.6.27/drivers/net/ehea/ehea_qmr.h patched_kernel/drivers/net/ehea/ehea_qmr.h --- linux-2.6.27/drivers/net/ehea/ehea_qmr.h 2008-10-24 09:29:19.000000000 +0200 +++ patched_kernel/drivers/net/ehea/ehea_qmr.h 2008-10-27 09:27:46.000000000 +0100 @@ -40,6 +40,9 @@ #define EHEA_PAGESIZE (1UL << EHEA_PAGESHIFT) #define EHEA_SECTSIZE (1UL << 24) #define EHEA_PAGES_PER_SECTION (EHEA_SECTSIZE >> EHEA_PAGESHIFT) +#define EHEA_HUGEPAGESHIFT 34 +#define EHEA_HUGEPAGE_SIZE (1UL << EHEA_HUGEPAGESHIFT) +#define EHEA_HUGEPAGE_PFN_MASK ((EHEA_HUGEPAGE_SIZE - 1) >> PAGE_SHIFT) #if ((1UL << SECTION_SIZE_BITS) < EHEA_SECTSIZE) #error eHEA module cannot work if kernel sectionsize < ehea sectionsize -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/