From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D5FF9C31E45 for ; Fri, 14 Jun 2019 00:20:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A37B921537 for ; Fri, 14 Jun 2019 00:20:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725836AbfFNAU4 (ORCPT ); Thu, 13 Jun 2019 20:20:56 -0400 Received: from mga01.intel.com ([192.55.52.88]:65198 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725906AbfFNAU4 (ORCPT ); Thu, 13 Jun 2019 20:20:56 -0400 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga101.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 13 Jun 2019 17:20:55 -0700 X-ExtLoop1: 1 Received: from iweiny-desk2.sc.intel.com ([10.3.52.157]) by FMSMGA003.fm.intel.com with ESMTP; 13 Jun 2019 17:20:55 -0700 Date: Thu, 13 Jun 2019 17:22:17 -0700 From: Ira Weiny To: Christoph Hellwig Cc: Dan Williams , =?iso-8859-1?B?Suly9G1l?= Glisse , Jason Gunthorpe , Ben Skeggs , linux-nvdimm@lists.01.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-mm@kvack.org, nouveau@lists.freedesktop.org Subject: Re: [PATCH 13/22] device-dax: use the dev_pagemap internal refcount Message-ID: <20190614002217.GB783@iweiny-DESK2.sc.intel.com> References: <20190613094326.24093-1-hch@lst.de> <20190613094326.24093-14-hch@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190613094326.24093-14-hch@lst.de> User-Agent: Mutt/1.11.1 (2018-12-01) Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Thu, Jun 13, 2019 at 11:43:16AM +0200, Christoph Hellwig wrote: > The functionality is identical to the one currently open coded in > device-dax. > > Signed-off-by: Christoph Hellwig > --- > drivers/dax/dax-private.h | 4 --- > drivers/dax/device.c | 52 +-------------------------------------- > 2 files changed, 1 insertion(+), 55 deletions(-) > > diff --git a/drivers/dax/dax-private.h b/drivers/dax/dax-private.h > index a45612148ca0..ed04a18a35be 100644 > --- a/drivers/dax/dax-private.h > +++ b/drivers/dax/dax-private.h > @@ -51,8 +51,6 @@ struct dax_region { > * @target_node: effective numa node if dev_dax memory range is onlined > * @dev - device core > * @pgmap - pgmap for memmap setup / lifetime (driver owned) > - * @ref: pgmap reference count (driver owned) > - * @cmp: @ref final put completion (driver owned) > */ > struct dev_dax { > struct dax_region *region; > @@ -60,8 +58,6 @@ struct dev_dax { > int target_node; > struct device dev; > struct dev_pagemap pgmap; > - struct percpu_ref ref; > - struct completion cmp; > }; > > static inline struct dev_dax *to_dev_dax(struct device *dev) > diff --git a/drivers/dax/device.c b/drivers/dax/device.c > index e23fa1bd8c97..a9d7c90ecf1e 100644 > --- a/drivers/dax/device.c > +++ b/drivers/dax/device.c > @@ -14,37 +14,6 @@ > #include "dax-private.h" > #include "bus.h" > > -static struct dev_dax *ref_to_dev_dax(struct percpu_ref *ref) > -{ > - return container_of(ref, struct dev_dax, ref); > -} > - > -static void dev_dax_percpu_release(struct percpu_ref *ref) > -{ > - struct dev_dax *dev_dax = ref_to_dev_dax(ref); > - > - dev_dbg(&dev_dax->dev, "%s\n", __func__); > - complete(&dev_dax->cmp); > -} > - > -static void dev_dax_percpu_exit(void *data) > -{ > - struct percpu_ref *ref = data; > - struct dev_dax *dev_dax = ref_to_dev_dax(ref); > - > - dev_dbg(&dev_dax->dev, "%s\n", __func__); > - wait_for_completion(&dev_dax->cmp); > - percpu_ref_exit(ref); > -} > - > -static void dev_dax_percpu_kill(struct dev_pagemap *pgmap) > -{ > - struct dev_dax *dev_dax = container_of(pgmap, struct dev_dax, pgmap); > - > - dev_dbg(&dev_dax->dev, "%s\n", __func__); > - percpu_ref_kill(pgmap->ref); > -} > - > static int check_vma(struct dev_dax *dev_dax, struct vm_area_struct *vma, > const char *func) > { > @@ -442,10 +411,6 @@ static void dev_dax_kill(void *dev_dax) > kill_dev_dax(dev_dax); > } > > -static const struct dev_pagemap_ops dev_dax_pagemap_ops = { > - .kill = dev_dax_percpu_kill, > -}; > - > int dev_dax_probe(struct device *dev) > { > struct dev_dax *dev_dax = to_dev_dax(dev); > @@ -463,24 +428,9 @@ int dev_dax_probe(struct device *dev) > return -EBUSY; > } > > - init_completion(&dev_dax->cmp); > - rc = percpu_ref_init(&dev_dax->ref, dev_dax_percpu_release, 0, > - GFP_KERNEL); > - if (rc) > - return rc; > - > - rc = devm_add_action_or_reset(dev, dev_dax_percpu_exit, &dev_dax->ref); > - if (rc) > - return rc; > - > - dev_dax->pgmap.ref = &dev_dax->ref; I don't think this exactly correct. pgmap.ref is a pointer to the dev_dax ref structure. Taking it away will cause devm_memremap_pages() to fail AFAICS. I think you need to change struct dev_pagemap as well: diff --git a/include/linux/memremap.h b/include/linux/memremap.h index f0628660d541..5e2120589ddf 100644 --- a/include/linux/memremap.h +++ b/include/linux/memremap.h @@ -90,7 +90,7 @@ struct dev_pagemap { struct vmem_altmap altmap; bool altmap_valid; struct resource res; - struct percpu_ref *ref; + struct percpu_ref ref; void (*kill)(struct percpu_ref *ref); struct device *dev; void *data; And all usages of it, right? Ira > - dev_dax->pgmap.ops = &dev_dax_pagemap_ops; > addr = devm_memremap_pages(dev, &dev_dax->pgmap); > - if (IS_ERR(addr)) { > - devm_remove_action(dev, dev_dax_percpu_exit, &dev_dax->ref); > - percpu_ref_exit(&dev_dax->ref); > + if (IS_ERR(addr)) > return PTR_ERR(addr); > - } > > inode = dax_inode(dax_dev); > cdev = inode->i_cdev; > -- > 2.20.1 > > _______________________________________________ > Linux-nvdimm mailing list > Linux-nvdimm@lists.01.org > https://lists.01.org/mailman/listinfo/linux-nvdimm