From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Darrick J. Wong" Subject: Re: [PATCH 03/18] btrfs: basic dax read Date: Tue, 21 May 2019 08:14:45 -0700 Message-ID: <20190521151445.GA5125@magnolia> References: <20190429172649.8288-1-rgoldwyn@suse.de> <20190429172649.8288-4-rgoldwyn@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20190429172649.8288-4-rgoldwyn-l3A5Bk7waGM@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linux-nvdimm-bounces-hn68Rpc1hR1g9hUCZPvPmw@public.gmane.org Sender: "Linux-nvdimm" To: Goldwyn Rodrigues Cc: kilobyte-b9QjgO8OEXPVItvQsEIGlw@public.gmane.org, jack-AlSwsSmVLrQ@public.gmane.org, linux-nvdimm-hn68Rpc1hR1g9hUCZPvPmw@public.gmane.org, nborisov-IBi9RG/b67k@public.gmane.org, david-FqsqvQoI3Ljby3iVrkZq2A@public.gmane.org, dsterba-AlSwsSmVLrQ@public.gmane.org, willy-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org, Goldwyn Rodrigues , linux-fsdevel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, hch-jcswGhMUV9g@public.gmane.org, linux-btrfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-nvdimm@lists.01.org On Mon, Apr 29, 2019 at 12:26:34PM -0500, Goldwyn Rodrigues wrote: > From: Goldwyn Rodrigues > > Perform a basic read using iomap support. The btrfs_iomap_begin() > finds the extent at the position and fills the iomap data > structure with the values. > > Signed-off-by: Goldwyn Rodrigues > --- > fs/btrfs/Makefile | 1 + > fs/btrfs/ctree.h | 5 +++++ > fs/btrfs/dax.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++ > fs/btrfs/file.c | 11 ++++++++++- > 4 files changed, 65 insertions(+), 1 deletion(-) > create mode 100644 fs/btrfs/dax.c > > diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile > index ca693dd554e9..1fa77b875ae9 100644 > --- a/fs/btrfs/Makefile > +++ b/fs/btrfs/Makefile > @@ -12,6 +12,7 @@ btrfs-y += super.o ctree.o extent-tree.o print-tree.o root-tree.o dir-item.o \ > reada.o backref.o ulist.o qgroup.o send.o dev-replace.o raid56.o \ > uuid-tree.o props.o free-space-tree.o tree-checker.o > > +btrfs-$(CONFIG_FS_DAX) += dax.o > btrfs-$(CONFIG_BTRFS_FS_POSIX_ACL) += acl.o > btrfs-$(CONFIG_BTRFS_FS_CHECK_INTEGRITY) += check-integrity.o > btrfs-$(CONFIG_BTRFS_FS_REF_VERIFY) += ref-verify.o > diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h > index 9512f49262dd..b7bbe5130a3b 100644 > --- a/fs/btrfs/ctree.h > +++ b/fs/btrfs/ctree.h > @@ -3795,6 +3795,11 @@ int btrfs_reada_wait(void *handle); > void btrfs_reada_detach(void *handle); > int btree_readahead_hook(struct extent_buffer *eb, int err); > > +#ifdef CONFIG_FS_DAX > +/* dax.c */ > +ssize_t btrfs_file_dax_read(struct kiocb *iocb, struct iov_iter *to); > +#endif /* CONFIG_FS_DAX */ > + > static inline int is_fstree(u64 rootid) > { > if (rootid == BTRFS_FS_TREE_OBJECTID || > diff --git a/fs/btrfs/dax.c b/fs/btrfs/dax.c > new file mode 100644 > index 000000000000..bf3d46b0acb6 > --- /dev/null > +++ b/fs/btrfs/dax.c > @@ -0,0 +1,49 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * DAX support for BTRFS > + * > + * Copyright (c) 2019 SUSE Linux > + * Author: Goldwyn Rodrigues > + */ > + > +#ifdef CONFIG_FS_DAX > +#include > +#include > +#include "ctree.h" > +#include "btrfs_inode.h" > + > +static int btrfs_iomap_begin(struct inode *inode, loff_t pos, > + loff_t length, unsigned flags, struct iomap *iomap) > +{ > + struct extent_map *em; > + struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); > + em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, pos, length, 0); > + if (em->block_start == EXTENT_MAP_HOLE) { > + iomap->type = IOMAP_HOLE; > + return 0; I'm not doing a rigorous review of the btrfs-specific pieces, but you're required to fill out the other iomap fields for a read hole. --D > + } > + iomap->type = IOMAP_MAPPED; > + iomap->bdev = em->bdev; > + iomap->dax_dev = fs_info->dax_dev; > + iomap->offset = em->start; > + iomap->length = em->len; > + iomap->addr = em->block_start; > + return 0; > +} > + > +static const struct iomap_ops btrfs_iomap_ops = { > + .iomap_begin = btrfs_iomap_begin, > +}; > + > +ssize_t btrfs_file_dax_read(struct kiocb *iocb, struct iov_iter *to) > +{ > + ssize_t ret; > + struct inode *inode = file_inode(iocb->ki_filp); > + > + inode_lock_shared(inode); > + ret = dax_iomap_rw(iocb, to, &btrfs_iomap_ops); > + inode_unlock_shared(inode); > + > + return ret; > +} > +#endif /* CONFIG_FS_DAX */ > diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c > index 34fe8a58b0e9..9194591f9eea 100644 > --- a/fs/btrfs/file.c > +++ b/fs/btrfs/file.c > @@ -3288,9 +3288,18 @@ static int btrfs_file_open(struct inode *inode, struct file *filp) > return generic_file_open(inode, filp); > } > > +static ssize_t btrfs_file_read_iter(struct kiocb *iocb, struct iov_iter *to) > +{ > +#ifdef CONFIG_FS_DAX > + if (IS_DAX(file_inode(iocb->ki_filp))) > + return btrfs_file_dax_read(iocb, to); > +#endif > + return generic_file_read_iter(iocb, to); > +} > + > const struct file_operations btrfs_file_operations = { > .llseek = btrfs_file_llseek, > - .read_iter = generic_file_read_iter, > + .read_iter = btrfs_file_read_iter, > .splice_read = generic_file_splice_read, > .write_iter = btrfs_file_write_iter, > .mmap = btrfs_file_mmap, > -- > 2.16.4 > 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=-8.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY, 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 6F0FBC04AAF for ; 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Tue, 21 May 2019 15:14:54 +0000 Received: from abhmp0003.oracle.com (abhmp0003.oracle.com [141.146.116.9]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id x4LFEld2015657; Tue, 21 May 2019 15:14:48 GMT Received: from localhost (/67.169.218.210) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Tue, 21 May 2019 15:14:47 +0000 Date: Tue, 21 May 2019 08:14:45 -0700 From: "Darrick J. Wong" To: Goldwyn Rodrigues Cc: linux-btrfs@vger.kernel.org, kilobyte@angband.pl, linux-fsdevel@vger.kernel.org, jack@suse.cz, david@fromorbit.com, willy@infradead.org, hch@lst.de, dsterba@suse.cz, nborisov@suse.com, linux-nvdimm@lists.01.org, Goldwyn Rodrigues Subject: Re: [PATCH 03/18] btrfs: basic dax read Message-ID: <20190521151445.GA5125@magnolia> References: <20190429172649.8288-1-rgoldwyn@suse.de> <20190429172649.8288-4-rgoldwyn@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190429172649.8288-4-rgoldwyn@suse.de> User-Agent: Mutt/1.9.4 (2018-02-28) X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=9264 signatures=668687 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=2 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1905210094 X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=9264 signatures=668687 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=2 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1905210094 Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On Mon, Apr 29, 2019 at 12:26:34PM -0500, Goldwyn Rodrigues wrote: > From: Goldwyn Rodrigues > > Perform a basic read using iomap support. The btrfs_iomap_begin() > finds the extent at the position and fills the iomap data > structure with the values. > > Signed-off-by: Goldwyn Rodrigues > --- > fs/btrfs/Makefile | 1 + > fs/btrfs/ctree.h | 5 +++++ > fs/btrfs/dax.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++ > fs/btrfs/file.c | 11 ++++++++++- > 4 files changed, 65 insertions(+), 1 deletion(-) > create mode 100644 fs/btrfs/dax.c > > diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile > index ca693dd554e9..1fa77b875ae9 100644 > --- a/fs/btrfs/Makefile > +++ b/fs/btrfs/Makefile > @@ -12,6 +12,7 @@ btrfs-y += super.o ctree.o extent-tree.o print-tree.o root-tree.o dir-item.o \ > reada.o backref.o ulist.o qgroup.o send.o dev-replace.o raid56.o \ > uuid-tree.o props.o free-space-tree.o tree-checker.o > > +btrfs-$(CONFIG_FS_DAX) += dax.o > btrfs-$(CONFIG_BTRFS_FS_POSIX_ACL) += acl.o > btrfs-$(CONFIG_BTRFS_FS_CHECK_INTEGRITY) += check-integrity.o > btrfs-$(CONFIG_BTRFS_FS_REF_VERIFY) += ref-verify.o > diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h > index 9512f49262dd..b7bbe5130a3b 100644 > --- a/fs/btrfs/ctree.h > +++ b/fs/btrfs/ctree.h > @@ -3795,6 +3795,11 @@ int btrfs_reada_wait(void *handle); > void btrfs_reada_detach(void *handle); > int btree_readahead_hook(struct extent_buffer *eb, int err); > > +#ifdef CONFIG_FS_DAX > +/* dax.c */ > +ssize_t btrfs_file_dax_read(struct kiocb *iocb, struct iov_iter *to); > +#endif /* CONFIG_FS_DAX */ > + > static inline int is_fstree(u64 rootid) > { > if (rootid == BTRFS_FS_TREE_OBJECTID || > diff --git a/fs/btrfs/dax.c b/fs/btrfs/dax.c > new file mode 100644 > index 000000000000..bf3d46b0acb6 > --- /dev/null > +++ b/fs/btrfs/dax.c > @@ -0,0 +1,49 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * DAX support for BTRFS > + * > + * Copyright (c) 2019 SUSE Linux > + * Author: Goldwyn Rodrigues > + */ > + > +#ifdef CONFIG_FS_DAX > +#include > +#include > +#include "ctree.h" > +#include "btrfs_inode.h" > + > +static int btrfs_iomap_begin(struct inode *inode, loff_t pos, > + loff_t length, unsigned flags, struct iomap *iomap) > +{ > + struct extent_map *em; > + struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); > + em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, pos, length, 0); > + if (em->block_start == EXTENT_MAP_HOLE) { > + iomap->type = IOMAP_HOLE; > + return 0; I'm not doing a rigorous review of the btrfs-specific pieces, but you're required to fill out the other iomap fields for a read hole. --D > + } > + iomap->type = IOMAP_MAPPED; > + iomap->bdev = em->bdev; > + iomap->dax_dev = fs_info->dax_dev; > + iomap->offset = em->start; > + iomap->length = em->len; > + iomap->addr = em->block_start; > + return 0; > +} > + > +static const struct iomap_ops btrfs_iomap_ops = { > + .iomap_begin = btrfs_iomap_begin, > +}; > + > +ssize_t btrfs_file_dax_read(struct kiocb *iocb, struct iov_iter *to) > +{ > + ssize_t ret; > + struct inode *inode = file_inode(iocb->ki_filp); > + > + inode_lock_shared(inode); > + ret = dax_iomap_rw(iocb, to, &btrfs_iomap_ops); > + inode_unlock_shared(inode); > + > + return ret; > +} > +#endif /* CONFIG_FS_DAX */ > diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c > index 34fe8a58b0e9..9194591f9eea 100644 > --- a/fs/btrfs/file.c > +++ b/fs/btrfs/file.c > @@ -3288,9 +3288,18 @@ static int btrfs_file_open(struct inode *inode, struct file *filp) > return generic_file_open(inode, filp); > } > > +static ssize_t btrfs_file_read_iter(struct kiocb *iocb, struct iov_iter *to) > +{ > +#ifdef CONFIG_FS_DAX > + if (IS_DAX(file_inode(iocb->ki_filp))) > + return btrfs_file_dax_read(iocb, to); > +#endif > + return generic_file_read_iter(iocb, to); > +} > + > const struct file_operations btrfs_file_operations = { > .llseek = btrfs_file_llseek, > - .read_iter = generic_file_read_iter, > + .read_iter = btrfs_file_read_iter, > .splice_read = generic_file_splice_read, > .write_iter = btrfs_file_write_iter, > .mmap = btrfs_file_mmap, > -- > 2.16.4 >