Re: [PATCH 0/2] f2fs: fix device alias state across remount

[Wenjie Qi]

Hi Daeho,

The f2fs-tools companion patch was sent separately. It populates
dev_alias_ino[] when mkfs assigns the alias inodes, before calculating
the superblock checksum, so a filesystem created with the updated tools
has the mapping on its first mount.

Current mkfs.f2fs accepts an arbitrary slash-free alias_filename.
Enforcing basename equality will prevent new custom aliases, but it does
not handle existing filesystems: after release and remount, reserve
cannot identify a custom-named alias, and has_alias is not restored for
pinned allocation.

The added superblock commit is needed only when the mapping is first
recorded, and the release ioctl already ends with a synchronous
checkpoint.

Should existing filesystems created with custom alias filenames remain
supported? If so, a tools-only restriction does not seem sufficient.

Thanks,
Wenjie