From: "Darrick J. Wong" Subject: Re: [PATCH v3 1/4] dax: introduce a fs_dax_get_by_bdev() helper Date: Wed, 30 Aug 2017 14:39:51 -0700 Message-ID: <20170830213951.GU4757@magnolia> References: <150412222686.10177.8031279869867070772.stgit@dwillia2-desk3.amr.corp.intel.com> <150412223265.10177.11004612169458058274.stgit@dwillia2-desk3.amr.corp.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-xfs@vger.kernel.org, linux-ext4@vger.kernel.org, Jan Kara , Christoph Hellwig , linux-nvdimm@lists.01.org To: Dan Williams Return-path: Received: from userp1040.oracle.com ([156.151.31.81]:17359 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751519AbdH3VkG (ORCPT ); Wed, 30 Aug 2017 17:40:06 -0400 Content-Disposition: inline In-Reply-To: <150412223265.10177.11004612169458058274.stgit@dwillia2-desk3.amr.corp.intel.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Wed, Aug 30, 2017 at 12:43:52PM -0700, Dan Williams wrote: > Add a helper that can replace the following common pattern: > > if (blk_queue_dax(bdev->bd_queue)) > fs_dax_get_by_host(bdev->bd_disk->disk_name); > > This will be used to move dax_device lookup from iomap-operation time to > fs-mount time. > > Cc: Jan Kara > Cc: Christoph Hellwig > Signed-off-by: Dan Williams Reviewed-by: Darrick J. Wong > --- > drivers/dax/super.c | 10 ++++++++++ > include/linux/dax.h | 6 ++++++ > 2 files changed, 16 insertions(+) > > diff --git a/drivers/dax/super.c b/drivers/dax/super.c > index 938eb4868f7f..b699aac268a6 100644 > --- a/drivers/dax/super.c > +++ b/drivers/dax/super.c > @@ -46,6 +46,8 @@ void dax_read_unlock(int id) > EXPORT_SYMBOL_GPL(dax_read_unlock); > > #ifdef CONFIG_BLOCK > +#include > + > int bdev_dax_pgoff(struct block_device *bdev, sector_t sector, size_t size, > pgoff_t *pgoff) > { > @@ -59,6 +61,14 @@ int bdev_dax_pgoff(struct block_device *bdev, sector_t sector, size_t size, > } > EXPORT_SYMBOL(bdev_dax_pgoff); > > +struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev) > +{ > + if (!blk_queue_dax(bdev->bd_queue)) > + return NULL; > + return fs_dax_get_by_host(bdev->bd_disk->disk_name); > +} > +EXPORT_SYMBOL_GPL(fs_dax_get_by_bdev); > + > /** > * __bdev_dax_supported() - Check if the device supports dax for filesystem > * @sb: The superblock of the device > diff --git a/include/linux/dax.h b/include/linux/dax.h > index df97b7af7e2c..ac8afa18f707 100644 > --- a/include/linux/dax.h > +++ b/include/linux/dax.h > @@ -57,6 +57,7 @@ static inline void fs_put_dax(struct dax_device *dax_dev) > put_dax(dax_dev); > } > > +struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev); > #else > static inline int bdev_dax_supported(struct super_block *sb, int blocksize) > { > @@ -71,6 +72,11 @@ static inline struct dax_device *fs_dax_get_by_host(const char *host) > static inline void fs_put_dax(struct dax_device *dax_dev) > { > } > + > +static inline struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev) > +{ > + return NULL; > +} > #endif > > int dax_read_lock(void); > > -- > To unsubscribe from this list: send the line "unsubscribe linux-xfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html