From patchwork Sun Sep 20 15:54:42 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Williams X-Patchwork-Id: 11787761 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 7B7806CB for ; Sun, 20 Sep 2020 16:13:10 +0000 (UTC) Received: from ml01.01.org (ml01.01.org [198.145.21.10]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 49EF0214F1 for ; Sun, 20 Sep 2020 16:13:09 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 49EF0214F1 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-nvdimm-bounces@lists.01.org Received: from ml01.vlan13.01.org (localhost [IPv6:::1]) by ml01.01.org (Postfix) with ESMTP id 846DB14C10C67; Sun, 20 Sep 2020 09:13:09 -0700 (PDT) Received-SPF: Pass (mailfrom) identity=mailfrom; client-ip=192.55.52.120; helo=mga04.intel.com; envelope-from=dan.j.williams@intel.com; receiver= Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 6100914C10C64 for ; Sun, 20 Sep 2020 09:13:06 -0700 (PDT) IronPort-SDR: ooritLJI75x9qyuaTYCjh3m6212mnF2ORPo4jOpv8IwcwliyY7BdkOxisxTd9h4/CLKbbUT5mN t0p3/y7Cq3JQ== X-IronPort-AV: E=McAfee;i="6000,8403,9750"; a="157634897" X-IronPort-AV: E=Sophos;i="5.77,283,1596524400"; d="scan'208";a="157634897" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga006.jf.intel.com ([10.7.209.51]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Sep 2020 09:13:02 -0700 IronPort-SDR: yj9pH4Dh9wal3PfBOIQJvHpSqfNHkQyrOcsKm59NQaCAEq3RE3CPuIrRXaYK1S+sxGO1eYq2Nb GMImt7ZQYgqg== X-IronPort-AV: E=Sophos;i="5.77,283,1596524400"; d="scan'208";a="308659989" Received: from dwillia2-desk3.jf.intel.com (HELO dwillia2-desk3.amr.corp.intel.com) ([10.54.39.16]) by orsmga006-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Sep 2020 09:13:01 -0700 Subject: [PATCH v4] dm: Call proper helper to determine dax support From: Dan Williams To: linux-nvdimm@lists.01.org Date: Sun, 20 Sep 2020 08:54:42 -0700 Message-ID: <160061715195.13131.5503173247632041975.stgit@dwillia2-desk3.amr.corp.intel.com> User-Agent: StGit/0.18-3-g996c MIME-Version: 1.0 Message-ID-Hash: OYPGDPYY42XHM3PSGMKRVVZCONVYWBZ4 X-Message-ID-Hash: OYPGDPYY42XHM3PSGMKRVVZCONVYWBZ4 X-MailFrom: dan.j.williams@intel.com X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; suspicious-header CC: stable@vger.kernel.org, Adrian Huang , Jan Kara , snitzer@redhat.com, kernel test robot , dm-devel@redhat.com, linux-kernel@vger.kernel.org, mpatocka@redhat.com X-Mailman-Version: 3.1.1 Precedence: list List-Id: "Linux-nvdimm developer list." Archived-At: List-Archive: List-Help: List-Post: List-Subscribe: List-Unsubscribe: From: Jan Kara DM was calling generic_fsdax_supported() to determine whether a device referenced in the DM table supports DAX. However this is a helper for "leaf" device drivers so that they don't have to duplicate common generic checks. High level code should call dax_supported() helper which that calls into appropriate helper for the particular device. This problem manifested itself as kernel messages: dm-3: error: dax access failed (-95) when lvm2-testsuite run in cases where a DM device was stacked on top of another DM device. Fixes: 7bf7eac8d648 ("dax: Arrange for dax_supported check to span multiple devices") Cc: Tested-by: Adrian Huang Signed-off-by: Jan Kara Acked-by: Mike Snitzer Reported-by: kernel test robot Signed-off-by: Dan Williams --- Changes since v3 [1]: - One more kbuild-robot report on dax_read_lock() needing to be guarded by "#if IS_ENABLED(CONFIG_DAX)" instead of "#ifdef CONFIG_DAX" since the latter does not handle the "=m" case. [2]: http://lore.kernel.org/r/160046028990.22670.15271558589864899328.stgit@dwillia2-desk3.amr.corp.intel.com drivers/dax/super.c | 4 ++++ drivers/md/dm-table.c | 10 +++++++--- include/linux/dax.h | 22 ++++++++++++++++++++-- 3 files changed, 31 insertions(+), 5 deletions(-) diff --git a/drivers/dax/super.c b/drivers/dax/super.c index e5767c83ea23..b6284c5cae0a 100644 --- a/drivers/dax/super.c +++ b/drivers/dax/super.c @@ -325,11 +325,15 @@ EXPORT_SYMBOL_GPL(dax_direct_access); bool dax_supported(struct dax_device *dax_dev, struct block_device *bdev, int blocksize, sector_t start, sector_t len) { + if (!dax_dev) + return false; + if (!dax_alive(dax_dev)) return false; return dax_dev->ops->dax_supported(dax_dev, bdev, blocksize, start, len); } +EXPORT_SYMBOL_GPL(dax_supported); size_t dax_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr, size_t bytes, struct iov_iter *i) diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index 5edc3079e7c1..229f461e7def 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -860,10 +860,14 @@ EXPORT_SYMBOL_GPL(dm_table_set_type); int device_supports_dax(struct dm_target *ti, struct dm_dev *dev, sector_t start, sector_t len, void *data) { - int blocksize = *(int *) data; + int blocksize = *(int *) data, id; + bool rc; - return generic_fsdax_supported(dev->dax_dev, dev->bdev, blocksize, - start, len); + id = dax_read_lock(); + rc = dax_supported(dev->dax_dev, dev->bdev, blocksize, start, len); + dax_read_unlock(id); + + return rc; } /* Check devices support synchronous DAX */ diff --git a/include/linux/dax.h b/include/linux/dax.h index 6904d4e0b2e0..497031392e0a 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -130,6 +130,8 @@ static inline bool generic_fsdax_supported(struct dax_device *dax_dev, return __generic_fsdax_supported(dax_dev, bdev, blocksize, start, sectors); } +bool dax_supported(struct dax_device *dax_dev, struct block_device *bdev, + int blocksize, sector_t start, sector_t len); static inline void fs_put_dax(struct dax_device *dax_dev) { @@ -157,6 +159,13 @@ static inline bool generic_fsdax_supported(struct dax_device *dax_dev, return false; } +static inline bool dax_supported(struct dax_device *dax_dev, + struct block_device *bdev, int blocksize, sector_t start, + sector_t len) +{ + return false; +} + static inline void fs_put_dax(struct dax_device *dax_dev) { } @@ -189,14 +198,23 @@ static inline void dax_unlock_page(struct page *page, dax_entry_t cookie) } #endif +#if IS_ENABLED(CONFIG_DAX) int dax_read_lock(void); void dax_read_unlock(int id); +#else +static inline int dax_read_lock(void) +{ + return 0; +} + +static inline void dax_read_unlock(int id) +{ +} +#endif /* CONFIG_DAX */ bool dax_alive(struct dax_device *dax_dev); void *dax_get_private(struct dax_device *dax_dev); long dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, long nr_pages, void **kaddr, pfn_t *pfn); -bool dax_supported(struct dax_device *dax_dev, struct block_device *bdev, - int blocksize, sector_t start, sector_t len); size_t dax_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr, size_t bytes, struct iov_iter *i); size_t dax_copy_to_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr,