Hi Chandan, Please pull this branch with changes for xfs for 6.9-rc1. As usual, I did a test-merge with the main upstream branch as of a few minutes ago, and didn't see any conflicts. Please let me know if you encounter any problems. --D The following changes since commit 1c51ac0998ed9baaca3ac75c0083b4c3b4d993ef: xfs: move setting bt_logical_sectorsize out of xfs_setsize_buftarg (2024-02-22 12:42:45 -0800) are available in the Git repository at: https://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux.git tags/in-memory-btrees-6.9_2024-02-23 for you to fetch changes up to 0dc63c8a1ce39c1ac7da536ee9174cdc714afae2: xfs: launder in-memory btree buffers before transaction commit (2024-02-22 12:43:36 -0800) ---------------------------------------------------------------- xfs: support in-memory btrees [v29.3 12/18] Online repair of the reverse-mapping btrees presens some unique challenges. To construct a new reverse mapping btree, we must scan the entire filesystem, but we cannot afford to quiesce the entire filesystem for the potentially lengthy scan. For rmap btrees, therefore, we relax our requirements of totally atomic repairs. Instead, repairs will scan all inodes, construct a new reverse mapping dataset, format a new btree, and commit it before anyone trips over the corruption. This is exactly the same strategy as was used in the quotacheck and nlink scanners. Unfortunately, the xfarray cannot perform key-based lookups and is therefore unsuitable for supporting live updates. Luckily, we already a data structure that maintains an indexed rmap recordset -- the existing rmap btree code! Hence we port the existing btree and buffer target code to be able to create a btree using the xfile we developed earlier. Live hooks keep the in-memory btree up to date for any resources that have already been scanned. This approach is not maximally memory efficient, but we can use the same rmap code that we do everywhere else, which provides improved stability without growing the code base even more. Note that in-memory btree blocks are always page sized. This patchset modifies the kernel xfs buffer cache to be capable of using a xfile (aka a shmem file) as a backing device. It then augments the btree code to support creating btree cursors with buffers that come from a buftarg other than the data device (namely an xfile-backed buftarg). For the userspace xfs buffer cache, we instead use a memfd or an O_TMPFILE file as a backing device. This has been running on the djcloud for months with no problems. Enjoy! Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx> ---------------------------------------------------------------- Christoph Hellwig (1): xfs: add a xfs_btree_ptrs_equal helper Darrick J. Wong (4): xfs: teach buftargs to maintain their own buffer hashtable xfs: support in-memory buffer cache targets xfs: support in-memory btrees xfs: launder in-memory btree buffers before transaction commit .../filesystems/xfs/xfs-online-fsck-design.rst | 5 +- fs/xfs/Kconfig | 8 + fs/xfs/Makefile | 2 + fs/xfs/libxfs/xfs_ag.c | 6 +- fs/xfs/libxfs/xfs_ag.h | 4 +- fs/xfs/libxfs/xfs_btree.c | 286 ++++++++++++++--- fs/xfs/libxfs/xfs_btree.h | 7 + fs/xfs/libxfs/xfs_btree_mem.c | 347 +++++++++++++++++++++ fs/xfs/libxfs/xfs_btree_mem.h | 75 +++++ fs/xfs/scrub/scrub.c | 5 + fs/xfs/scrub/scrub.h | 3 + fs/xfs/xfs_buf.c | 214 ++++++++----- fs/xfs/xfs_buf.h | 17 + fs/xfs/xfs_buf_mem.c | 270 ++++++++++++++++ fs/xfs/xfs_buf_mem.h | 34 ++ fs/xfs/xfs_health.c | 3 + fs/xfs/xfs_mount.h | 3 - fs/xfs/xfs_trace.c | 2 + fs/xfs/xfs_trace.h | 167 +++++++++- fs/xfs/xfs_trans.h | 1 + fs/xfs/xfs_trans_buf.c | 42 +++ 21 files changed, 1363 insertions(+), 138 deletions(-) create mode 100644 fs/xfs/libxfs/xfs_btree_mem.c create mode 100644 fs/xfs/libxfs/xfs_btree_mem.h create mode 100644 fs/xfs/xfs_buf_mem.c create mode 100644 fs/xfs/xfs_buf_mem.h
