From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-x244.google.com (mail-pa0-x244.google.com [IPv6:2607:f8b0:400e:c03::244]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 7E3EC1A1E01 for ; Sun, 26 Jun 2016 23:48:47 -0700 (PDT) Received: by mail-pa0-x244.google.com with SMTP id ts6so14618532pac.0 for ; Sun, 26 Jun 2016 23:48:13 -0700 (PDT) From: "Lee, Chun-Yi" Subject: [PATCH v3] acpi, nfit: treat volatile virtual CD region as pmem Date: Mon, 27 Jun 2016 14:46:00 +0800 Message-Id: <1467009960-20580-1-git-send-email-jlee@suse.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-nvdimm-bounces@lists.01.org Sender: "Linux-nvdimm" To: Ross Zwisler , Dan Williams , "Rafael J. Wysocki" , Linda Knippers Cc: "Lee, Chun-Yi" , linux-acpi@vger.kernel.org, Gary Lin , linux-kernel@vger.kernel.org, linux-nvdimm@lists.01.org List-ID: This patch adds logic to treat volatile virtual CD region as pmem region, then /dev/pmem* device can be mounted with iso9660. It's useful to work with the httpboot in EFI firmware to pull a remote ISO file to the local memory region for booting and installation. Wiki page of UEFI HTTPBoot with OVMF: https://en.opensuse.org/UEFI_HTTPBoot_with_OVMF The ramdisk function in EDK2/OVMF generates a ACPI0012 root device that it contains empty _STA but without _DSM: DefinitionBlock ("ssdt2.aml", "SSDT", 2, "INTEL ", "RamDisk ", 0x00001000) { Scope (\_SB) { Device (NVDR) { Name (_HID, "ACPI0012") // _HID: Hardware ID Name (_STR, Unicode ("NVDIMM Root Device")) // _STR: Description String Method (_STA, 0, NotSerialized) // _STA: Status { Return (0x0F) } } } } In section 5.2.25.2 of ACPI 6.1 spec, it mentions that the "SPA Range Structure Index" of VCD SPA shall be set to zero. That means VCD SPA will not be associated by any NVDIMM region mapping. The VCD's SPA Range Structure in NFIT is similar to virtual disk region as following: [028h 0040 2] Subtable Type : 0000 [System Physical Address Range] [02Ah 0042 2] Length : 0038 [02Ch 0044 2] Range Index : 0000 [02Eh 0046 2] Flags (decoded below) : 0000 Add/Online Operation Only : 0 Proximity Domain Valid : 0 [030h 0048 4] Reserved : 00000000 [034h 0052 4] Proximity Domain : 00000000 [038h 0056 16] Address Range GUID : 77AB535A-45FC-624B-5560-F7B281D1F96E [048h 0072 8] Address Range Base : 00000000B6ABD018 [050h 0080 8] Address Range Length : 0000000005500000 [058h 0088 8] Memory Map Attribute : 0000000000000000 The way to not associate a SPA range is to never reference it from a "flush hint", "interleave", or "control region" table. After testing on OVMF, pmem driver can support the region that it doesn't assoicate to any NVDIMM mapping. So, treat VCD like pmem is a idea to get a pmem block device that it contains iso. v3: To simplify patch, removed VCD region in libnvdimm. v2: Removed the code for setting VCD to a read-only region. Cc: Gary Lin Cc: Dan Williams Cc: Ross Zwisler Cc: "Rafael J. Wysocki" Cc: Linda Knippers Signed-off-by: Lee, Chun-Yi --- drivers/acpi/nfit.c | 8 +++++++- drivers/nvdimm/region_devs.c | 26 +++++++++++++++++++++++++- include/linux/libnvdimm.h | 2 ++ 3 files changed, 34 insertions(+), 2 deletions(-) Index: linux/drivers/acpi/nfit.c =================================================================== --- linux.orig/drivers/acpi/nfit.c +++ linux/drivers/acpi/nfit.c @@ -1995,7 +1995,7 @@ static int acpi_nfit_register_region(str if (nfit_spa->nd_region) return 0; - if (spa->range_index == 0) { + if (spa->range_index == 0 && nfit_spa_type(spa) != NFIT_SPA_VCD) { dev_dbg(acpi_desc->dev, "%s: detected invalid spa index\n", __func__); return 0; @@ -2059,6 +2059,11 @@ static int acpi_nfit_register_region(str ndr_desc); if (!nfit_spa->nd_region) rc = -ENOMEM; + } else if (nfit_spa_type(spa) == NFIT_SPA_VCD) { + nfit_spa->nd_region = nvdimm_pmem_region_create(nvdimm_bus, + ndr_desc); + if (!nfit_spa->nd_region) + rc = -ENOMEM; } out: _______________________________________________ Linux-nvdimm mailing list Linux-nvdimm@lists.01.org https://lists.01.org/mailman/listinfo/linux-nvdimm