Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754588AbbDRUIG (ORCPT ); Sat, 18 Apr 2015 16:08:06 -0400 Received: from mail-wg0-f46.google.com ([74.125.82.46]:36718 "EHLO mail-wg0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751907AbbDRUID (ORCPT ); Sat, 18 Apr 2015 16:08:03 -0400 MIME-Version: 1.0 In-Reply-To: <20150418080702.GB28706@kroah.com> References: <20150418013256.25237.96403.stgit@dwillia2-desk3.amr.corp.intel.com> <20150418013546.25237.86836.stgit@dwillia2-desk3.amr.corp.intel.com> <20150418080702.GB28706@kroah.com> Date: Sat, 18 Apr 2015 13:08:01 -0700 Message-ID: Subject: Re: [PATCH 06/21] nd: ndctl class device, and nd bus attributes From: Dan Williams To: Greg KH Cc: "linux-nvdimm@lists.01.org" , Neil Brown , "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3898 Lines: 99 On Sat, Apr 18, 2015 at 1:07 AM, Greg KH wrote: > On Fri, Apr 17, 2015 at 09:35:46PM -0400, Dan Williams wrote: >> This is the position (device topology) independent method to find all >> the NFIT-defined buses in the system. The expectation is that there >> will only ever be one "nd" bus discovered via /sys/class/nd/ndctl0. >> However, we allow for the possibility of multiple buses and they will >> listed in discovery order as ndctl0...ndctlN. This character device >> hosts the ioctl for passing control messages (as defined by the NFIT >> spec). The "format" and "revision" attributes of this device identify >> the format of the messages. In the event an NFIT is registered with an >> unknown/unsupported control message format then the "format" attribute >> will not be visible. >> >> Cc: Greg KH >> Cc: Neil Brown >> Signed-off-by: Dan Williams >> --- >> drivers/block/nd/Makefile | 1 >> drivers/block/nd/bus.c | 84 +++++++++++++++++++++++++++++++++++++++++ >> drivers/block/nd/core.c | 71 ++++++++++++++++++++++++++++++++++- >> drivers/block/nd/nd-private.h | 5 ++ >> 4 files changed, 160 insertions(+), 1 deletion(-) >> create mode 100644 drivers/block/nd/bus.c >> >> diff --git a/drivers/block/nd/Makefile b/drivers/block/nd/Makefile >> index c6bec0c185c5..7772fb599809 100644 >> --- a/drivers/block/nd/Makefile >> +++ b/drivers/block/nd/Makefile >> @@ -20,3 +20,4 @@ obj-$(CONFIG_NFIT_ACPI) += nd_acpi.o >> nd_acpi-y := acpi.o >> >> nd-y := core.o >> +nd-y += bus.o >> diff --git a/drivers/block/nd/bus.c b/drivers/block/nd/bus.c >> new file mode 100644 >> index 000000000000..c27db50511f2 >> --- /dev/null >> +++ b/drivers/block/nd/bus.c >> @@ -0,0 +1,84 @@ >> +/* >> + * Copyright(c) 2013-2015 Intel Corporation. All rights reserved. >> + * >> + * This program is free software; you can redistribute it and/or modify >> + * it under the terms of version 2 of the GNU General Public License as >> + * published by the Free Software Foundation. >> + * >> + * This program is distributed in the hope that it will be useful, but >> + * WITHOUT ANY WARRANTY; without even the implied warranty of >> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU >> + * General Public License for more details. >> + */ >> +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include "nd-private.h" >> +#include "nfit.h" >> + >> +static int nd_major; >> +static struct class *nd_class; >> + >> +int nd_bus_create_ndctl(struct nd_bus *nd_bus) >> +{ >> + dev_t devt = MKDEV(nd_major, nd_bus->id); >> + struct device *dev; >> + >> + dev = device_create(nd_class, &nd_bus->dev, devt, nd_bus, "ndctl%d", >> + nd_bus->id); >> + >> + if (IS_ERR(dev)) { >> + dev_dbg(&nd_bus->dev, "failed to register ndctl%d: %ld\n", >> + nd_bus->id, PTR_ERR(dev)); >> + return PTR_ERR(dev); >> + } >> + return 0; >> +} >> + >> +void nd_bus_destroy_ndctl(struct nd_bus *nd_bus) >> +{ >> + device_destroy(nd_class, MKDEV(nd_major, nd_bus->id)); >> +} >> + >> +static long nd_ioctl(struct file *file, unsigned int cmd, unsigned long arg) >> +{ >> + return -ENXIO; >> +} > > There is no ioctl call here, so why even have this character device? Our management library finds nd buses by /sys/class/nd. The nd_ioctl() gets filled out in "[PATCH 08/21] nd: ndctl.h, the nd ioctl abi". -- 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/