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=-10.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 279ACC433E1 for ; Sat, 1 Aug 2020 03:43:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 101A32087C for ; Sat, 1 Aug 2020 03:43:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728888AbgHADnR (ORCPT ); Fri, 31 Jul 2020 23:43:17 -0400 Received: from mga05.intel.com ([192.55.52.43]:65144 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728853AbgHADnQ (ORCPT ); Fri, 31 Jul 2020 23:43:16 -0400 IronPort-SDR: RB/ykID0KZlObcXcrK9xKhOwoErNGxjtZY7cw+t5tb1864sv9pNO+0tEnnsEZwZKtJL3qlFEvU gOI6vhJZxcIg== X-IronPort-AV: E=McAfee;i="6000,8403,9699"; a="236763127" X-IronPort-AV: E=Sophos;i="5.75,420,1589266800"; d="scan'208";a="236763127" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 Jul 2020 20:43:14 -0700 IronPort-SDR: Wu4/goeeob0gX4X8fBdtAUM2j8WaXrOl+H/VkkWKFacZqrY56uGWFVt19dhVdcM+CdGsh9D7da oZ5fZUU8jizw== X-IronPort-AV: E=Sophos;i="5.75,420,1589266800"; d="scan'208";a="321647484" Received: from dwillia2-desk3.jf.intel.com (HELO dwillia2-desk3.amr.corp.intel.com) ([10.54.39.16]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 Jul 2020 20:43:14 -0700 Subject: [PATCH v3 21/23] device-dax: Add an 'align' attribute From: Dan Williams To: akpm@linux-foundation.org Cc: Joao Martins , peterz@infradead.org, vishal.l.verma@intel.com, dave.hansen@linux.intel.com, ard.biesheuvel@linaro.org, vishal.l.verma@intel.com, linux-mm@kvack.org, linux-nvdimm@lists.01.org, joao.m.martins@oracle.com, linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, dri-devel@lists.freedesktop.org Date: Fri, 31 Jul 2020 20:26:56 -0700 Message-ID: <159625241660.3040297.3801913809845542130.stgit@dwillia2-desk3.amr.corp.intel.com> In-Reply-To: <159625229779.3040297.11363509688097221416.stgit@dwillia2-desk3.amr.corp.intel.com> References: <159625229779.3040297.11363509688097221416.stgit@dwillia2-desk3.amr.corp.intel.com> User-Agent: StGit/0.18-3-g996c MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org From: Joao Martins Introduce a device align attribute. While doing so, rename the region align attribute to be more explicitly named as so, but keep it named as @align to retain the API for tools like daxctl. Changes on align may not always be valid, when say certain mappings were created with 2M and then we switch to 1G. So, we validate all ranges against the new value being attempted, post resizing. Signed-off-by: Joao Martins Link: https://lore.kernel.org/r/20200716172913.19658-3-joao.m.martins@oracle.com Signed-off-by: Dan Williams --- drivers/dax/bus.c | 102 ++++++++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 92 insertions(+), 10 deletions(-) diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c index feca1413481c..7a9439132573 100644 --- a/drivers/dax/bus.c +++ b/drivers/dax/bus.c @@ -230,14 +230,15 @@ static ssize_t region_size_show(struct device *dev, static struct device_attribute dev_attr_region_size = __ATTR(size, 0444, region_size_show, NULL); -static ssize_t align_show(struct device *dev, +static ssize_t region_align_show(struct device *dev, struct device_attribute *attr, char *buf) { struct dax_region *dax_region = dev_get_drvdata(dev); return sprintf(buf, "%u\n", dax_region->align); } -static DEVICE_ATTR_RO(align); +static struct device_attribute dev_attr_region_align = + __ATTR(align, 0400, region_align_show, NULL); #define for_each_dax_region_resource(dax_region, res) \ for (res = (dax_region)->res.child; res; res = res->sibling) @@ -488,7 +489,7 @@ static umode_t dax_region_visible(struct kobject *kobj, struct attribute *a, static struct attribute *dax_region_attributes[] = { &dev_attr_available_size.attr, &dev_attr_region_size.attr, - &dev_attr_align.attr, + &dev_attr_region_align.attr, &dev_attr_create.attr, &dev_attr_seed.attr, &dev_attr_delete.attr, @@ -855,15 +856,13 @@ static ssize_t size_show(struct device *dev, return sprintf(buf, "%llu\n", size); } -static bool alloc_is_aligned(struct dax_region *dax_region, - resource_size_t size) +static bool alloc_is_aligned(struct dev_dax *dev_dax, resource_size_t size) { /* * The minimum mapping granularity for a device instance is a * single subsection, unless the arch says otherwise. */ - return IS_ALIGNED(size, max_t(unsigned long, dax_region->align, - memremap_compat_align())); + return IS_ALIGNED(size, max_t(unsigned long, dev_dax->align, memremap_compat_align())); } static int dev_dax_shrink(struct dev_dax *dev_dax, resource_size_t size) @@ -958,7 +957,7 @@ static ssize_t dev_dax_resize(struct dax_region *dax_region, return dev_dax_shrink(dev_dax, size); to_alloc = size - dev_size; - if (dev_WARN_ONCE(dev, !alloc_is_aligned(dax_region, to_alloc), + if (dev_WARN_ONCE(dev, !alloc_is_aligned(dev_dax, to_alloc), "resize of %pa misaligned\n", &to_alloc)) return -ENXIO; @@ -1022,7 +1021,7 @@ static ssize_t size_store(struct device *dev, struct device_attribute *attr, if (rc) return rc; - if (!alloc_is_aligned(dax_region, val)) { + if (!alloc_is_aligned(dev_dax, val)) { dev_dbg(dev, "%s: size: %lld misaligned\n", __func__, val); return -EINVAL; } @@ -1041,6 +1040,87 @@ static ssize_t size_store(struct device *dev, struct device_attribute *attr, } static DEVICE_ATTR_RW(size); +static ssize_t align_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct dev_dax *dev_dax = to_dev_dax(dev); + + return sprintf(buf, "%d\n", dev_dax->align); +} + +static ssize_t dev_dax_validate_align(struct dev_dax *dev_dax) +{ + resource_size_t dev_size = dev_dax_size(dev_dax); + struct device *dev = &dev_dax->dev; + ssize_t rc, i; + + if (dev->driver) + return -EBUSY; + + rc = -EINVAL; + if (dev_size > 0 && !alloc_is_aligned(dev_dax, dev_size)) { + dev_dbg(dev, "%s: align %u invalid for size %llu\n", + __func__, dev_dax->align, dev_size); + return rc; + } + + for (i = 0; i < dev_dax->nr_range; i++) { + size_t len = range_len(&dev_dax->ranges[i].range); + + if (!alloc_is_aligned(dev_dax, len)) { + dev_dbg(dev, "%s: align %u invalid for range %ld\n", + __func__, dev_dax->align, i); + return rc; + } + } + + switch (dev_dax->align) { + case PUD_SIZE: + if (!IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)) + break; + fallthrough; + case PMD_SIZE: + if (!has_transparent_hugepage()) + break; + fallthrough; + case PAGE_SIZE: + rc = 0; + break; + } + + return rc; +} + +static ssize_t align_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t len) +{ + struct dev_dax *dev_dax = to_dev_dax(dev); + struct dax_region *dax_region = dev_dax->region; + unsigned long long val, align_save; + ssize_t rc; + + rc = kstrtoull(buf, 0, &val); + if (rc) + return -ENXIO; + + device_lock(dax_region->dev); + if (!dax_region->dev->driver) { + device_unlock(dax_region->dev); + return -ENXIO; + } + + device_lock(dev); + align_save = dev_dax->align; + dev_dax->align = val; + rc = dev_dax_validate_align(dev_dax); + if (rc) + dev_dax->align = align_save; + device_unlock(dev); + device_unlock(dax_region->dev); + return rc == 0 ? len : rc; +} +static DEVICE_ATTR_RW(align); + static int dev_dax_target_node(struct dev_dax *dev_dax) { struct dax_region *dax_region = dev_dax->region; @@ -1101,7 +1181,8 @@ static umode_t dev_dax_visible(struct kobject *kobj, struct attribute *a, int n) return 0; if (a == &dev_attr_numa_node.attr && !IS_ENABLED(CONFIG_NUMA)) return 0; - if (a == &dev_attr_size.attr && is_static(dax_region)) + if ((a == &dev_attr_align.attr || + a == &dev_attr_size.attr) && is_static(dax_region)) return 0444; return a->mode; } @@ -1110,6 +1191,7 @@ static struct attribute *dev_dax_attributes[] = { &dev_attr_modalias.attr, &dev_attr_size.attr, &dev_attr_target_node.attr, + &dev_attr_align.attr, &dev_attr_resource.attr, &dev_attr_numa_node.attr, NULL,