On Thu, Apr 27, 2023 at 4:05 PM Amir Goldstein <amir73il@xxxxxxxxx> wrote: > > Miklos, > > This v2 combines the prep patch set [1] and lazy lookup patch set [2]. > > This work is motivated by Alexander's composefs use case. > Alexander has been developing and testing his fsverity patches over > my lazy-lowerdata-lookup branch [3]. FYI, I rebased this branch on top of v6.4-rc2 and on top of branch ovl-fixes with the NULL pointer defer fix patches from Zhihao Cheng: https://lore.kernel.org/linux-unionfs/20230516141619.2160800-1-chengzhihao1@xxxxxxxxxx/ Thanks, Amir. > > Alexander has also written tests for lazy lowerdata lookup [4]. > > Note that patch #1 is a Fixes patch for stable. > Gao commented that the fix may not be complete, but I think it is better > than no fix at all. > > Regarding lazy lookup in d_real(), I am not sure if the best effort > lookup is the best solution, but in any case, none of this code kicks in > without explicit opt-in to data-only layers, so the risk of breaking > existing setups is quite low. > > Thanks, > Amir. > > Changes since v1: > - Include the prep patch set > - Split remove lowerdata from add lowerdata_redirect patch > - Remove embedded ovl_entry stack optimization > - Add lazy lookup and comment in d_real_inode() > - Improve documentation of :: data-only layers syntax > - Added RVBs > > [1] https://lore.kernel.org/linux-unionfs/20230408164302.1392694-1-amir73il@xxxxxxxxx/ > [2] https://lore.kernel.org/linux-unionfs/20230412135412.1684197-1-amir73il@xxxxxxxxx/ > [3] https://github.com/amir73il/linux/commits/ovl-lazy-lowerdata > [4] https://github.com/amir73il/xfstests/commits/ovl-lazy-lowerdata > > Amir Goldstein (13): > ovl: update of dentry revalidate flags after copy up > ovl: use OVL_E() and OVL_E_FLAGS() accessors > ovl: use ovl_numlower() and ovl_lowerstack() accessors > ovl: factor out ovl_free_entry() and ovl_stack_*() helpers > ovl: move ovl_entry into ovl_inode > ovl: deduplicate lowerpath and lowerstack[] > ovl: deduplicate lowerdata and lowerstack[] > ovl: remove unneeded goto instructions > ovl: introduce data-only lower layers > ovl: implement lookup in data-only layers > ovl: prepare to store lowerdata redirect for lazy lowerdata lookup > ovl: prepare for lazy lookup of lowerdata inode > ovl: implement lazy lookup of lowerdata in data-only layers > > Documentation/filesystems/overlayfs.rst | 36 +++++ > fs/overlayfs/copy_up.c | 11 ++ > fs/overlayfs/dir.c | 3 +- > fs/overlayfs/export.c | 41 +++--- > fs/overlayfs/file.c | 21 ++- > fs/overlayfs/inode.c | 38 +++-- > fs/overlayfs/namei.c | 185 +++++++++++++++++++----- > fs/overlayfs/overlayfs.h | 20 ++- > fs/overlayfs/ovl_entry.h | 73 ++++++++-- > fs/overlayfs/super.c | 132 ++++++++++------- > fs/overlayfs/util.c | 165 ++++++++++++++++----- > 11 files changed, 534 insertions(+), 191 deletions(-) > > -- > 2.34.1 >
