mirror of
https://github.com/torvalds/linux.git
synced 2026-05-05 23:05:25 -04:00
a111901f52
If fsck finds a key that needs work done, the primary example being an unlinked inode that needs to be deleted, and the key is in an internal snapshot node, we have a bit of a conundrum. The conundrum is that internal snapshot nodes are shared, and we in general do updates in internal snapshot nodes because there may be overwrites in some snapshots and not others, and this may affect other keys referenced by this key (i.e. extents). For example, we might be seeing an unlinked inode in an internal snapshot node, but then in one child snapshot the inode might have been reattached and might not be unlinked. Deleting the inode in the internal snapshot node would be wrong, because then we'll delete all the extents that the child snapshot references. But if an unlinked inode does not have any overwrites in child snapshots, we're fine: the inode is overwrritten in all child snapshots, so we can do the deletion at the point of comonality in the snapshot tree, i.e. the node where we found it. This patch adds a new helper, bch2_propagate_key_to_snapshot_leaves(), to handle the case where we need a to update a key that does have overwrites in child snapshots: we copy the key to leaf snapshot nodes, and then rewind fsck and process the needed updates there. With this, fsck can now always correctly handle unlinked inodes found in internal snapshot nodes. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.