16 Commits

Author SHA1 Message Date
Kent Overstreet
85e95ca7cc bcachefs: Update export_operations for snapshots
When support for snapshots was merged, export operations weren't
updated yet. This patch adds new filehandle types for bcachefs that
include the subvolume ID and updates export operations for subvolumes -
and also .get_parent, support for which was added just prior to
snapshots.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:17 -04:00
Kent Overstreet
4db650277d bcachefs: Subvol dirents are now only visible in parent subvol
This changes the on disk format for dirents that point to subvols so
that they also record the subvolid of the parent subvol, so that we can
filter them out in other subvolumes.

This also updates the dirent code to do that filtering, and in
particular tweaks the rename code - we need to ensure that there's only
ever one dirent (counting multiplicities in different snapshots) that
point to a subvolume.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:14 -04:00
Kent Overstreet
42d237320e bcachefs: Snapshot creation, deletion
This is the final patch in the patch series implementing snapshots.
This patch implements two new ioctls that work like creation and
deletion of directories, but fancier.

 - BCH_IOCTL_SUBVOLUME_CREATE, for creating new subvolumes and snaphots
 - BCH_IOCTL_SUBVOLUME_DESTROY, for deleting subvolumes and snapshots

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:13 -04:00
Kent Overstreet
6fed42bb77 bcachefs: Plumb through subvolume id
To implement snapshots, we need every filesystem btree operation (every
btree operation without a subvolume) to start by looking up the
subvolume and getting the current snapshot ID, with
bch2_subvolume_get_snapshot() - then, that snapshot ID is used for doing
btree lookups in BTREE_ITER_FILTER_SNAPSHOTS mode.

This patch adds those bch2_subvolume_get_snapshot() calls, and also
switches to passing around a subvol_inum instead of just an inode
number.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:12 -04:00
Kent Overstreet
b9e1adf579 bcachefs: Add support for dirents that point to subvolumes
Dirents currently always point to inodes. Subvolumes add a new type of
dirent, with d_type DT_SUBVOL, that instead points to an entry in the
subvolumes btree, and the subvolume has a pointer to the root inode.

This patch adds bch2_dirent_read_target() to get the inode (and
potentially subvolume) a dirent points to, and changes existing code to
use that instead of reading from d_inum directly.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:12 -04:00
Kent Overstreet
67e0dd8f0d bcachefs: btree_path
This splits btree_iter into two components: btree_iter is now the
externally visible componont, and it points to a btree_path which is now
reference counted.

This means we no longer have to clone iterators up front if they might
be mutated - btree_path can be shared by multiple iterators, and cloned
if an iterator would mutate a shared btree_path. This will help us use
iterators more efficiently, as well as slimming down the main long lived
state in btree_trans, and significantly cleans up the logic for iterator
lifetimes.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:11 -04:00
Kent Overstreet
ab2a29ccff bcachefs: Inode backpointers
This patch adds two new inode fields, bi_dir and bi_dir_offset, that
point back to the inode's dirent.

Since we're only adding fields for a single backpointer, files that have
been hardlinked won't necessarily have valid backpointers: we also add a
new inode flag, BCH_INODE_BACKPTR_UNTRUSTED, that's set if an inode has
ever had multiple links to it. That's ok, because we only really need
this functionality for directories, which can never have multiple
hardlinks - when we add subvolumes, we'll need a way to enemurate and
print subvolumes, and this will let us reconstruct a path to a subvolume
root given a subvolume root inode.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:58 -04:00
Kent Overstreet
b1fd23df1d bcachefs: Convert all bch2_trans_commit() users to BTREE_INSERT_ATOMIC
BTREE_INSERT_ATOMIC should really be the default mode, and there's not
that much code that doesn't need it - so this is prep work for getting
rid of the flag.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:33 -04:00
Kent Overstreet
63fbf458cb bcachefs: Can't be holding read locks while taking write locks
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:28 -04:00
Kent Overstreet
9638574229 bcachefs: Factor out fs-common.c
This refactoring makes the code easier to understand by separating the
bcachefs btree transactional code from the linux VFS code - but more
importantly, it's also to share code with the fuse port.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:28 -04:00
Kent Overstreet
6bd1305735 bcachefs: Fsck locking improvements
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:19 -04:00
Kent Overstreet
26609b619f bcachefs: Make bkey types globally unique
this lets us get rid of a lot of extra switch statements - in a lot of
places we dispatch on the btree node type, and then the key type, so
this is a nice cleanup across a lot of code.

Also improve the on disk format versioning stuff.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:12 -04:00
Kent Overstreet
319f9ac38e bcachefs: revamp to_text methods
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:11 -04:00
Kent Overstreet
741daa5be5 bcachefs: Dirent repair code
There was a bug for awhile in previous kernels where we weren't
computing dirent name lengths correctly and we weren't zeroing out
padding at the end of dirents (due to struct bch_dirent changing size by
adding __attribute__((aligned)), and not updating other code to use
offsetof).

This patch fixes dirents with junk at the end, by going off of the
dirent's hash.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:09 -04:00
Kent Overstreet
277c981c63 bcachefs: fix bch2_val_to_text()
was returning wrong value

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:08 -04:00
Kent Overstreet
1c6fdbd8f2 bcachefs: Initial commit
Initially forked from drivers/md/bcache, bcachefs is a new copy-on-write
filesystem with every feature you could possibly want.

Website: https://bcachefs.org

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:07 -04:00