From: Shiyang Ruan <ruansy.fnst@cn.fujitsu.com> To: <linux-kernel@vger.kernel.org>, <linux-xfs@vger.kernel.org>, <linux-nvdimm@lists.01.org> Cc: linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, darrick.wong@oracle.com, david@fromorbit.com, hch@lst.de, rgoldwyn@suse.de, qi.fuli@fujitsu.com, y-goto@fujitsu.com Subject: [RFC PATCH 0/8] fsdax: introduce FS query interface to support reflink Date: Fri, 7 Aug 2020 21:13:28 +0800 [thread overview] Message-ID: <20200807131336.318774-1-ruansy.fnst@cn.fujitsu.com> (raw) This patchset is a try to resolve the problem of tracking shared page for fsdax. Instead of per-page tracking method, this patchset introduces a query interface: get_shared_files(), which is implemented by each FS, to obtain the owners of a shared page. It returns an owner list of this shared page. Then, the memory-failure() iterates the list to be able to notify each process using files that sharing this page. The design of the tracking method is as follow: 1. dax_assocaite_entry() associates the owner's info to this page - For non-reflink case: page->mapping,->index stores the file's mapping, offset in file. A dax page is not shared by other files. dax_associate_entry() is called only once. So, use page->mapping,->index to store the owner's info. - For reflink case: page->mapping,->index stores the block device, offset in device. A dax page is shared more than once. So, dax_assocaite_entry() will be called more than once. We introduce page->zone_device_data as reflink counter, to indicate that this page is shared and how many owners now is using this page. The page->mapping,->index is used to store the block_device of the fs and page offset of this device. 2. dax_lock_page() calls query interface to lock each dax entry - For non-reflink case: owner's info is stored in page->mapping,->index. So, It is easy to lock its dax entry. - For reflink case: owner's info is obtained by calling get_shared_files(), which is implemented by FS. The FS context could be found in block_device that stored by page->mapping. Then lock the dax entries of the owners. In memory-failure(), since the owner list has been obtained in dax_lock_page(), just iterate the list and handle the error. This patchset didn't handle the memory failure on metadata of FS because I haven't found a way to distinguish whether this page contains matadata yet. Still working on it. == I also borrowed and made some changes on Goldwyn's patchsets. These patches makes up for the lack of CoW mechanism in fsdax. The rests are dax & reflink support for xfs. (Rebased on v5.8) == Shiyang Ruan (8): fs: introduce get_shared_files() for dax&reflink fsdax, mm: track files sharing dax page for memory-failure fsdax: introduce dax_copy_edges() for COW fsdax: copy data before write fsdax: replace mmap entry in case of CoW fsdax: dedup file range to use a compare function fs/xfs: handle CoW for fsdax write() path fs/xfs: support dedupe for fsdax fs/btrfs/reflink.c | 3 +- fs/dax.c | 302 +++++++++++++++++++++++++++++++++++------ fs/ocfs2/file.c | 2 +- fs/read_write.c | 11 +- fs/xfs/xfs_bmap_util.c | 6 +- fs/xfs/xfs_file.c | 10 +- fs/xfs/xfs_iomap.c | 3 +- fs/xfs/xfs_iops.c | 11 +- fs/xfs/xfs_reflink.c | 80 ++++++----- fs/xfs/xfs_super.c | 67 +++++++++ include/linux/dax.h | 18 ++- include/linux/fs.h | 11 +- include/linux/mm.h | 8 ++ mm/memory-failure.c | 138 ++++++++++++------- 14 files changed, 529 insertions(+), 141 deletions(-) -- 2.27.0 _______________________________________________ Linux-nvdimm mailing list -- linux-nvdimm@lists.01.org To unsubscribe send an email to linux-nvdimm-leave@lists.01.org
WARNING: multiple messages have this Message-ID (diff)
From: Shiyang Ruan <ruansy.fnst@cn.fujitsu.com> To: <linux-kernel@vger.kernel.org>, <linux-xfs@vger.kernel.org>, <linux-nvdimm@lists.01.org> Cc: <linux-mm@kvack.org>, <linux-fsdevel@vger.kernel.org>, <darrick.wong@oracle.com>, <dan.j.williams@intel.com>, <david@fromorbit.com>, <hch@lst.de>, <rgoldwyn@suse.de>, <qi.fuli@fujitsu.com>, <y-goto@fujitsu.com> Subject: [RFC PATCH 0/8] fsdax: introduce FS query interface to support reflink Date: Fri, 7 Aug 2020 21:13:28 +0800 [thread overview] Message-ID: <20200807131336.318774-1-ruansy.fnst@cn.fujitsu.com> (raw) This patchset is a try to resolve the problem of tracking shared page for fsdax. Instead of per-page tracking method, this patchset introduces a query interface: get_shared_files(), which is implemented by each FS, to obtain the owners of a shared page. It returns an owner list of this shared page. Then, the memory-failure() iterates the list to be able to notify each process using files that sharing this page. The design of the tracking method is as follow: 1. dax_assocaite_entry() associates the owner's info to this page - For non-reflink case: page->mapping,->index stores the file's mapping, offset in file. A dax page is not shared by other files. dax_associate_entry() is called only once. So, use page->mapping,->index to store the owner's info. - For reflink case: page->mapping,->index stores the block device, offset in device. A dax page is shared more than once. So, dax_assocaite_entry() will be called more than once. We introduce page->zone_device_data as reflink counter, to indicate that this page is shared and how many owners now is using this page. The page->mapping,->index is used to store the block_device of the fs and page offset of this device. 2. dax_lock_page() calls query interface to lock each dax entry - For non-reflink case: owner's info is stored in page->mapping,->index. So, It is easy to lock its dax entry. - For reflink case: owner's info is obtained by calling get_shared_files(), which is implemented by FS. The FS context could be found in block_device that stored by page->mapping. Then lock the dax entries of the owners. In memory-failure(), since the owner list has been obtained in dax_lock_page(), just iterate the list and handle the error. This patchset didn't handle the memory failure on metadata of FS because I haven't found a way to distinguish whether this page contains matadata yet. Still working on it. == I also borrowed and made some changes on Goldwyn's patchsets. These patches makes up for the lack of CoW mechanism in fsdax. The rests are dax & reflink support for xfs. (Rebased on v5.8) == Shiyang Ruan (8): fs: introduce get_shared_files() for dax&reflink fsdax, mm: track files sharing dax page for memory-failure fsdax: introduce dax_copy_edges() for COW fsdax: copy data before write fsdax: replace mmap entry in case of CoW fsdax: dedup file range to use a compare function fs/xfs: handle CoW for fsdax write() path fs/xfs: support dedupe for fsdax fs/btrfs/reflink.c | 3 +- fs/dax.c | 302 +++++++++++++++++++++++++++++++++++------ fs/ocfs2/file.c | 2 +- fs/read_write.c | 11 +- fs/xfs/xfs_bmap_util.c | 6 +- fs/xfs/xfs_file.c | 10 +- fs/xfs/xfs_iomap.c | 3 +- fs/xfs/xfs_iops.c | 11 +- fs/xfs/xfs_reflink.c | 80 ++++++----- fs/xfs/xfs_super.c | 67 +++++++++ include/linux/dax.h | 18 ++- include/linux/fs.h | 11 +- include/linux/mm.h | 8 ++ mm/memory-failure.c | 138 ++++++++++++------- 14 files changed, 529 insertions(+), 141 deletions(-) -- 2.27.0
next reply other threads:[~2020-08-07 13:13 UTC|newest] Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top 2020-08-07 13:13 Shiyang Ruan [this message] 2020-08-07 13:13 ` [RFC PATCH 0/8] fsdax: introduce FS query interface to support reflink Shiyang Ruan 2020-08-07 13:13 ` [RFC PATCH 1/8] fs: introduce get_shared_files() for dax&reflink Shiyang Ruan 2020-08-07 13:13 ` Shiyang Ruan 2020-08-07 16:15 ` Darrick J. Wong 2020-08-07 16:15 ` Darrick J. Wong 2020-08-10 8:07 ` Ruan Shiyang 2020-08-10 8:07 ` Ruan Shiyang 2020-08-07 13:13 ` [RFC PATCH 2/8] fsdax, mm: track files sharing dax page for memory-failure Shiyang Ruan 2020-08-07 13:13 ` Shiyang Ruan 2020-08-07 13:13 ` [RFC PATCH 3/8] fsdax: introduce dax_copy_edges() for COW Shiyang Ruan 2020-08-07 13:13 ` Shiyang Ruan 2020-08-07 13:13 ` [RFC PATCH 4/8] fsdax: copy data before write Shiyang Ruan 2020-08-07 13:13 ` Shiyang Ruan 2020-08-07 13:13 ` [RFC PATCH 5/8] fsdax: replace mmap entry in case of CoW Shiyang Ruan 2020-08-07 13:13 ` Shiyang Ruan 2020-08-07 13:13 ` [RFC PATCH 6/8] fsdax: dedup file range to use a compare function Shiyang Ruan 2020-08-07 13:13 ` Shiyang Ruan 2020-08-07 13:13 ` [RFC PATCH 7/8] fs/xfs: handle CoW for fsdax write() path Shiyang Ruan 2020-08-07 13:13 ` Shiyang Ruan 2020-08-07 13:13 ` [RFC PATCH 8/8] fs/xfs: support dedupe for fsdax Shiyang Ruan 2020-08-07 13:13 ` Shiyang Ruan 2020-08-07 15:38 ` kernel test robot 2020-08-07 15:54 ` kernel test robot 2020-08-07 13:38 ` [RFC PATCH 0/8] fsdax: introduce FS query interface to support reflink Matthew Wilcox 2020-08-07 13:38 ` Matthew Wilcox 2020-08-10 8:15 ` Ruan Shiyang 2020-08-10 8:15 ` Ruan Shiyang 2020-08-10 11:16 ` Matthew Wilcox 2020-08-10 11:16 ` Matthew Wilcox 2020-08-10 21:10 ` Dave Chinner 2020-08-10 21:10 ` Dave Chinner
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20200807131336.318774-1-ruansy.fnst@cn.fujitsu.com \ --to=ruansy.fnst@cn.fujitsu.com \ --cc=darrick.wong@oracle.com \ --cc=david@fromorbit.com \ --cc=hch@lst.de \ --cc=linux-fsdevel@vger.kernel.org \ --cc=linux-kernel@vger.kernel.org \ --cc=linux-mm@kvack.org \ --cc=linux-nvdimm@lists.01.org \ --cc=linux-xfs@vger.kernel.org \ --cc=qi.fuli@fujitsu.com \ --cc=rgoldwyn@suse.de \ --cc=y-goto@fujitsu.com \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.