Here's a set of patches that:
(1) Removes calls to save/replace_mount_options() where the filesystem
then implements ->show_options() anyway, ignoring ->s_options.
(2) Makes all filesystems implement the ->show_options() superblock
operation rather than using generic_show_options(). If necessary,
extra information is stored in the superblock information.
(3) Deletes save_mount_options(), replace_mount_options(),
generic_show_options() and super_block::s_options.
This makes it easier to implement a context-based mount where the options
are passed individually over a file descriptor. It also allows duplicate
options, options that override each other and ignored options to be
resolved rather than storing irrelevant data.
Further, a lot of the time, all the information we want to display is
stored in the super block information anyway, so the option string is
redundant.
Some things I noted whilst doing this:
(1) A number of filesystems take uid/gid options. Should these be
reported relative to the observer's user namespace rather than init's
user namespace? After all, you can't then use those uid/gid options
if the numbers are interpreted incorrectly if you try and forge a
mount command from them.
(2) Should I provide a helper for displaying uid/gid options?
(3) How much do we need to worry about racing with remount? Some
filesystems happily give out the contents of the super_block without
regard to the fact that remount might be changing it simultaneously -
ext4, for example.
(4) What string options actually need 'munging'?
These patches can be found here:
https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/log/?h=for-viro
on top of three other minor patches.
David
---
David Howells (14):
VFS: Don't use save/replace_mount_options if not using generic_show_options
hugetlbfs: Implement show_options
omfs: Implement show_options
pstore: Implement show_options
ramfs: Implement show_options
bpf: Implement show_options
spufs: Implement show_options
befs: Implement show_options
affs: Implement show_options
afs: Implement show_options
isofs: Implement show_options
9p: Implement show_options
orangefs: Implement show_options
VFS: Kill off s_options and helpers
Documentation/filesystems/vfs.txt | 6 --
arch/powerpc/platforms/cell/spufs/inode.c | 21 +++++++--
fs/9p/v9fs.c | 59 ++++++++++++++++++++++++
fs/9p/v9fs.h | 3 +
fs/9p/vfs_super.c | 6 +-
fs/affs/super.c | 42 +++++++++++++++--
fs/afs/super.c | 45 ++++++++++++++++++-
fs/befs/linuxvfs.c | 24 +++++++++-
fs/btrfs/super.c | 1
fs/debugfs/inode.c | 2 -
fs/efivarfs/super.c | 1
fs/hugetlbfs/inode.c | 70 +++++++++++++++++++++++------
fs/isofs/inode.c | 51 ++++++++++++++++++++-
fs/isofs/isofs.h | 3 +
fs/namespace.c | 59 ------------------------
fs/omfs/inode.c | 33 ++++++++++++--
fs/orangefs/super.c | 15 ++++++
fs/pstore/inode.c | 14 +++++-
fs/pstore/internal.h | 3 +
fs/pstore/platform.c | 2 -
fs/ramfs/inode.c | 32 +++++++++----
fs/reiserfs/super.c | 4 --
fs/super.c | 1
fs/tracefs/inode.c | 2 -
include/linux/fs.h | 9 ----
include/linux/hugetlb.h | 3 +
include/net/9p/client.h | 13 +++++
include/net/9p/transport.h | 1
kernel/bpf/inode.c | 16 +++++--
net/9p/client.c | 25 ++++++++++
net/9p/trans_fd.c | 31 ++++++++++++-
net/9p/trans_rdma.c | 31 ++++++++++++-
32 files changed, 481 insertions(+), 147 deletions(-)
