Merge patch series "super: convert to a plain hashtable"

Christian Brauner <brauner@kernel.org> says:

Convert the rhltable to a plain hashtable under a spinlock. The walks
keep their place with a cursor entry in the chain. A claim is unhashed
the moment it's dropped and a walk that finds a superblock that isn't
born yet waits for it to be born or to die and looks again. Since
hashing can't fail anymore the entry for the superblock's own s_dev is
embedded in struct super_block and the preallocation in alloc_super()
goes away. This all simplifies things quite a lot.

It also fixes a btrfs bug where fs_bdev_freeze() ended up freezing a
btrfs filesystem through a stale member that open_ctree() had already
released while the freeze was waiting for SB_BORN. The resume doesn't
find a holder for that device anymore so the filesystem stays frozen
for good.

The selftest freezes a device that several erofs superblocks share.
That's the one case where a device legitimately carries claims from more
than one superblock and it checks that a suspend freezes each of them
exactly once and that mounts coming and going under a suspended device
leave nothing frozen behind.

I modeled the table in TLA+ and checked the real list code with CBMC.
Both agree with the design.

* patches from https://patch.msgid.link/20261012-work-super-dev_hash-v1-0-305cf71cd334@kernel.org:
  super: convert to plain hashtable
  selftests/filesystems: add a test for freezing a shared block device

Link: https://patch.msgid.link/20261012-work-super-dev_hash-v1-0-305cf71cd334@kernel.org
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>

0 files changed, 0 insertions, 0 deletions