From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932842AbbCEMBX (ORCPT ); Thu, 5 Mar 2015 07:01:23 -0500 Received: from mail-wi0-f174.google.com ([209.85.212.174]:39128 "EHLO mail-wi0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932732AbbCEMBV (ORCPT ); Thu, 5 Mar 2015 07:01:21 -0500 Message-ID: <54F8458E.2060202@plexistor.com> Date: Thu, 05 Mar 2015 14:01:18 +0200 From: Boaz Harrosh User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.5.0 MIME-Version: 1.0 To: Ingo Molnar , x86@kernel.org, linux-kernel , "Roger C. Pao" , Dan Williams , Thomas Gleixner , linux-nvdimm , "H. Peter Anvin" , Matthew Wilcox , Andy Lutomirski , Christoph Hellwig CC: Ross Zwisler Subject: [PATCH 8/8] OUT-OF-TREE: pmem: Allow request_mem to fail (BLK_DEV_PMEM_IGNORE_REQUEST_MEM_RET) References: <54F82CE0.4040502@plexistor.com> <54F830D4.7030205@plexistor.com> In-Reply-To: <54F830D4.7030205@plexistor.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org With old Kernels there was a bug in x86 where any unknown memory chip type would come up BUSY when calling request_mem_region_exclusive(). So for pmem to work with old Kernels and real NvDIMM chips we have a new Kconfig option CONFIG_BLK_DEV_PMEM_IGNORE_REQUEST_MEM_RET. People have been running with hacked up pmem that will ignore the return code from request_mem_region_exclusive. So here it is official Signed-off-by: Boaz Harrosh --- drivers/block/Kconfig | 12 ++++++++++++ drivers/block/pmem.c | 9 ++++++--- 2 files changed, 18 insertions(+), 3 deletions(-) diff --git a/drivers/block/Kconfig b/drivers/block/Kconfig index 635fa6a..58a2c69 100644 --- a/drivers/block/Kconfig +++ b/drivers/block/Kconfig @@ -435,6 +435,18 @@ config BLK_DEV_PMEM_USE_PAGES to other devices in the system, then you must say "Yes" here. If unsure leave as Yes. +config BLK_DEV_PMEM_IGNORE_REQUEST_MEM_RET + bool "Ignore the return code from request_mem_region_exclusive" + depends on BLK_DEV_PMEM + help + In Old Kernels type-12 Memory type which is used by NvDIMM + chips Comes out busy when calling request_mem_region_exclusive, + because of a bug. + If this option is set to "yes". The pmem will ignore the + failure, and continue as usual. If you have an old Kernel and + a real NvDIMM chip you must say yes here. + (Ignored if BLK_DEV_PMEM_USE_PAGES=y) + config CDROM_PKTCDVD tristate "Packet writing on CD/DVD media" depends on !UML diff --git a/drivers/block/pmem.c b/drivers/block/pmem.c index d0c80f4..ba1167c 100644 --- a/drivers/block/pmem.c +++ b/drivers/block/pmem.c @@ -172,8 +172,10 @@ int pmem_mapmem(struct pmem_device *pmem) "pmem"); if (unlikely(!res_mem)) { pr_warn("pmem: request_mem_region_exclusive phys=0x%llx size=0x%zx failed\n", - pmem->phys_addr, pmem->size); - return -EINVAL; + pmem->phys_addr, pmem->size); +#ifndef CONFIG_BLK_DEV_PMEM_IGNORE_REQUEST_MEM_RET + return -EBUSY; +#endif } pmem->virt_addr = ioremap_cache(pmem->phys_addr, pmem->size); @@ -184,7 +186,8 @@ int pmem_mapmem(struct pmem_device *pmem) return 0; out_release: - release_mem_region(pmem->phys_addr, pmem->size); + if (res_mem) + release_mem_region(pmem->phys_addr, pmem->size); return err; } -- 1.9.3