[PATCH v5 0/2] erofs: share the superblock for file-backed mounts

This series adds a "superblock_share" mount option for file-backed EROFS
mounts.  When set, mounting the same backing file (identified by inode and
fsoffset) with compatible options reuses the existing superblock instead
of creating a new one, so the page cache and inode cache are shared across
all mounts of the image.  Without the option the behaviour is unchanged.

v4: https://lore.kernel.org/linux-fsdevel/[email protected]/
v3: https://lore.kernel.org/linux-fsdevel/[email protected]/
v2: https://lore.kernel.org/linux-fsdevel/[email protected]/
v1: https://lore.kernel.org/linux-fsdevel/[email protected]/
Needs: https://lore.kernel.org/linux-fsdevel/[email protected]/

Giuseppe Scrivano (2):
  fs: rename vfs_get_super() to get_tree_super() and export it
  erofs: reuse superblock for file-backed mounts

 Documentation/filesystems/erofs.rst |  8 ++++
 fs/erofs/internal.h                 |  1 +
 fs/erofs/super.c                    | 58 +++++++++++++++++++++++++++--
 fs/super.c                          | 19 ++++++++--
 include/linux/fs_context.h          |  4 ++
 5 files changed, 83 insertions(+), 7 deletions(-)

-- 
2.55.0