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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED 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 8916AC070C3 for ; Thu, 13 Sep 2018 02:34:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3AB4520882 for ; Thu, 13 Sep 2018 02:34:12 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3AB4520882 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727745AbeIMHla (ORCPT ); Thu, 13 Sep 2018 03:41:30 -0400 Received: from mga12.intel.com ([192.55.52.136]:44432 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726399AbeIMHla (ORCPT ); Thu, 13 Sep 2018 03:41:30 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga106.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 12 Sep 2018 19:34:10 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.53,367,1531810800"; d="scan'208";a="262148447" Received: from dwillia2-desk3.jf.intel.com (HELO dwillia2-desk3.amr.corp.intel.com) ([10.54.39.16]) by fmsmga005.fm.intel.com with ESMTP; 12 Sep 2018 19:34:09 -0700 Subject: [PATCH v5 5/7] mm, hmm: Use devm semantics for hmm_devmem_{add, remove} From: Dan Williams To: akpm@linux-foundation.org Cc: Christoph Hellwig , =?utf-8?b?SsOpcsO0bWU=?= Glisse , Logan Gunthorpe , alexander.h.duyck@intel.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Date: Wed, 12 Sep 2018 19:22:27 -0700 Message-ID: <153680534781.453305.3660438915028111950.stgit@dwillia2-desk3.amr.corp.intel.com> In-Reply-To: <153680531988.453305.8080706591516037706.stgit@dwillia2-desk3.amr.corp.intel.com> References: <153680531988.453305.8080706591516037706.stgit@dwillia2-desk3.amr.corp.intel.com> User-Agent: StGit/0.18-2-gc94f MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org devm semantics arrange for resources to be torn down when device-driver-probe fails or when device-driver-release completes. Similar to devm_memremap_pages() there is no need to support an explicit remove operation when the users properly adhere to devm semantics. Note that devm_kzalloc() automatically handles allocating node-local memory. Reviewed-by: Christoph Hellwig Cc: "Jérôme Glisse" Cc: Logan Gunthorpe Signed-off-by: Dan Williams --- include/linux/hmm.h | 4 -- mm/hmm.c | 127 ++++++++++----------------------------------------- 2 files changed, 25 insertions(+), 106 deletions(-) diff --git a/include/linux/hmm.h b/include/linux/hmm.h index 4c92e3ba3e16..5ec8635f602c 100644 --- a/include/linux/hmm.h +++ b/include/linux/hmm.h @@ -499,8 +499,7 @@ struct hmm_devmem { * enough and allocate struct page for it. * * The device driver can wrap the hmm_devmem struct inside a private device - * driver struct. The device driver must call hmm_devmem_remove() before the - * device goes away and before freeing the hmm_devmem struct memory. + * driver struct. */ struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops, struct device *device, @@ -508,7 +507,6 @@ struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops, struct hmm_devmem *hmm_devmem_add_resource(const struct hmm_devmem_ops *ops, struct device *device, struct resource *res); -void hmm_devmem_remove(struct hmm_devmem *devmem); /* * hmm_devmem_page_set_drvdata - set per-page driver data field diff --git a/mm/hmm.c b/mm/hmm.c index c968e49f7a0c..ec1d9eccf176 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -939,7 +939,6 @@ static void hmm_devmem_ref_exit(void *data) devmem = container_of(ref, struct hmm_devmem, ref); percpu_ref_exit(ref); - devm_remove_action(devmem->device, &hmm_devmem_ref_exit, data); } static void hmm_devmem_ref_kill(void *data) @@ -950,7 +949,6 @@ static void hmm_devmem_ref_kill(void *data) devmem = container_of(ref, struct hmm_devmem, ref); percpu_ref_kill(ref); wait_for_completion(&devmem->completion); - devm_remove_action(devmem->device, &hmm_devmem_ref_kill, data); } static int hmm_devmem_fault(struct vm_area_struct *vma, @@ -988,7 +986,7 @@ static void hmm_devmem_radix_release(struct resource *resource) mutex_unlock(&hmm_devmem_lock); } -static void hmm_devmem_release(struct device *dev, void *data) +static void hmm_devmem_release(void *data) { struct hmm_devmem *devmem = data; struct resource *resource = devmem->resource; @@ -996,11 +994,6 @@ static void hmm_devmem_release(struct device *dev, void *data) struct zone *zone; struct page *page; - if (percpu_ref_tryget_live(&devmem->ref)) { - dev_WARN(dev, "%s: page mapping is still live!\n", __func__); - percpu_ref_put(&devmem->ref); - } - /* pages are dead and unused, undo the arch mapping */ start_pfn = (resource->start & ~(PA_SECTION_SIZE - 1)) >> PAGE_SHIFT; npages = ALIGN(resource_size(resource), PA_SECTION_SIZE) >> PAGE_SHIFT; @@ -1124,19 +1117,6 @@ static int hmm_devmem_pages_create(struct hmm_devmem *devmem) return ret; } -static int hmm_devmem_match(struct device *dev, void *data, void *match_data) -{ - struct hmm_devmem *devmem = data; - - return devmem->resource == match_data; -} - -static void hmm_devmem_pages_remove(struct hmm_devmem *devmem) -{ - devres_release(devmem->device, &hmm_devmem_release, - &hmm_devmem_match, devmem->resource); -} - /* * hmm_devmem_add() - hotplug ZONE_DEVICE memory for device memory * @@ -1164,8 +1144,7 @@ struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops, dev_pagemap_get_ops(); - devmem = devres_alloc_node(&hmm_devmem_release, sizeof(*devmem), - GFP_KERNEL, dev_to_node(device)); + devmem = devm_kzalloc(device, sizeof(*devmem), GFP_KERNEL); if (!devmem) return ERR_PTR(-ENOMEM); @@ -1179,11 +1158,11 @@ struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops, ret = percpu_ref_init(&devmem->ref, &hmm_devmem_ref_release, 0, GFP_KERNEL); if (ret) - goto error_percpu_ref; + return ERR_PTR(ret); - ret = devm_add_action(device, hmm_devmem_ref_exit, &devmem->ref); + ret = devm_add_action_or_reset(device, hmm_devmem_ref_exit, &devmem->ref); if (ret) - goto error_devm_add_action; + return ERR_PTR(ret); size = ALIGN(size, PA_SECTION_SIZE); addr = min((unsigned long)iomem_resource.end, @@ -1203,16 +1182,12 @@ struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops, devmem->resource = devm_request_mem_region(device, addr, size, dev_name(device)); - if (!devmem->resource) { - ret = -ENOMEM; - goto error_no_resource; - } + if (!devmem->resource) + return ERR_PTR(-ENOMEM); break; } - if (!devmem->resource) { - ret = -ERANGE; - goto error_no_resource; - } + if (!devmem->resource) + return ERR_PTR(-ERANGE); devmem->resource->desc = IORES_DESC_DEVICE_PRIVATE_MEMORY; devmem->pfn_first = devmem->resource->start >> PAGE_SHIFT; @@ -1221,28 +1196,13 @@ struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops, ret = hmm_devmem_pages_create(devmem); if (ret) - goto error_pages; - - devres_add(device, devmem); + return ERR_PTR(ret); - ret = devm_add_action(device, hmm_devmem_ref_kill, &devmem->ref); - if (ret) { - hmm_devmem_remove(devmem); + ret = devm_add_action_or_reset(device, hmm_devmem_release, devmem); + if (ret) return ERR_PTR(ret); - } return devmem; - -error_pages: - devm_release_mem_region(device, devmem->resource->start, - resource_size(devmem->resource)); -error_no_resource: -error_devm_add_action: - hmm_devmem_ref_kill(&devmem->ref); - hmm_devmem_ref_exit(&devmem->ref); -error_percpu_ref: - devres_free(devmem); - return ERR_PTR(ret); } EXPORT_SYMBOL(hmm_devmem_add); @@ -1258,8 +1218,7 @@ struct hmm_devmem *hmm_devmem_add_resource(const struct hmm_devmem_ops *ops, dev_pagemap_get_ops(); - devmem = devres_alloc_node(&hmm_devmem_release, sizeof(*devmem), - GFP_KERNEL, dev_to_node(device)); + devmem = devm_kzalloc(device, sizeof(*devmem), GFP_KERNEL); if (!devmem) return ERR_PTR(-ENOMEM); @@ -1273,12 +1232,12 @@ struct hmm_devmem *hmm_devmem_add_resource(const struct hmm_devmem_ops *ops, ret = percpu_ref_init(&devmem->ref, &hmm_devmem_ref_release, 0, GFP_KERNEL); if (ret) - goto error_percpu_ref; + return ERR_PTR(ret); - ret = devm_add_action(device, hmm_devmem_ref_exit, &devmem->ref); + ret = devm_add_action_or_reset(device, hmm_devmem_ref_exit, + &devmem->ref); if (ret) - goto error_devm_add_action; - + return ERR_PTR(ret); devmem->pfn_first = devmem->resource->start >> PAGE_SHIFT; devmem->pfn_last = devmem->pfn_first + @@ -1286,59 +1245,21 @@ struct hmm_devmem *hmm_devmem_add_resource(const struct hmm_devmem_ops *ops, ret = hmm_devmem_pages_create(devmem); if (ret) - goto error_devm_add_action; + return ERR_PTR(ret); - devres_add(device, devmem); + ret = devm_add_action_or_reset(device, hmm_devmem_release, devmem); + if (ret) + return ERR_PTR(ret); - ret = devm_add_action(device, hmm_devmem_ref_kill, &devmem->ref); - if (ret) { - hmm_devmem_remove(devmem); + ret = devm_add_action_or_reset(device, hmm_devmem_ref_kill, + &devmem->ref); + if (ret) return ERR_PTR(ret); - } return devmem; - -error_devm_add_action: - hmm_devmem_ref_kill(&devmem->ref); - hmm_devmem_ref_exit(&devmem->ref); -error_percpu_ref: - devres_free(devmem); - return ERR_PTR(ret); } EXPORT_SYMBOL(hmm_devmem_add_resource); -/* - * hmm_devmem_remove() - remove device memory (kill and free ZONE_DEVICE) - * - * @devmem: hmm_devmem struct use to track and manage the ZONE_DEVICE memory - * - * This will hot-unplug memory that was hotplugged by hmm_devmem_add on behalf - * of the device driver. It will free struct page and remove the resource that - * reserved the physical address range for this device memory. - */ -void hmm_devmem_remove(struct hmm_devmem *devmem) -{ - resource_size_t start, size; - struct device *device; - bool cdm = false; - - if (!devmem) - return; - - device = devmem->device; - start = devmem->resource->start; - size = resource_size(devmem->resource); - - cdm = devmem->resource->desc == IORES_DESC_DEVICE_PUBLIC_MEMORY; - hmm_devmem_ref_kill(&devmem->ref); - hmm_devmem_ref_exit(&devmem->ref); - hmm_devmem_pages_remove(devmem); - - if (!cdm) - devm_release_mem_region(device, start, size); -} -EXPORT_SYMBOL(hmm_devmem_remove); - /* * A device driver that wants to handle multiple devices memory through a * single fake device can use hmm_device to do so. This is purely a helper