The following changes since commit d0b3b7b22dfa1f4b515fd3a295b3fd958f9e81af:
Linux 6.16-rc4 (2025-06-29 13:09:04 -0700)
are available in the Git repository at:
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs.git tags/pull-mount
for you to fetch changes up to a7cce099450f8fc597a6ac215440666610895fb7:
statmount_mnt_basic(): simplify the logics for group id (2025-06-29 19:03:46 -0400)
----------------------------------------------------------------
mount changes. I've got more stuff in the local tree, but
this is getting too much for one merge window as it is.
* mount hash conflicts rudiments are gone now - we do not allow
multiple mounts with the same parent/mountpoint to be
hashed at the same time.
* struct mount changes
mnt_umounting is gone;
mnt_slave_list/mnt_slave is an hlist now;
overmounts are kept track of by explicit pointer in mount;
a bunch of flags moved out of mnt_flags to a new field,
with only namespace_sem for protection;
mnt_expiry is protected by mount_lock now (instead of
namespace_sem);
MNT_LOCKED is used only for mounts that need to remain
attached to their parents to prevent mountpoint exposure -
no more overloading it for absolute roots;
all mnt_list uses are transient now - it's used only to
represent temporary sets during umount_tree().
* mount refcounting change
children no longer pin parents for any mounts, whether they'd
passed through umount_tree() or not.
* struct mountpoint changes
refcount is no more; what matters is ->m_list emptiness;
instead of temporary bumping the refcount, we insert a new object
(pinned_mountpoint) into ->m_list;
new calling conventions for lock_mount() and friends.
* do_move_mount()/attach_recursive_mnt() seriously cleaned up.
* globals in fs/pnode.c are gone.
* propagate_mnt(), change_mnt_propagation() and propagate_umount() cleaned up
(in the last case - pretty much completely rewritten).
* freeing of emptied mnt_namespace is done in namespace_unlock()
for one thing, there are subtle ordering requirements there;
for another it simplifies cleanups.
* assorted cleanups.
* restore the machinery for long-term mounts from accumulated bitrot.
This is going to get a followup come next cycle, when #work.fs_context
with its change of vfs_fs_parse_string() calling conventions goes
into -next.
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Al Viro (48):
attach_mnt(): expand in attach_recursive_mnt(), then lose the flag argument
get rid of mnt_set_mountpoint_beneath()
prevent mount hash conflicts
copy_tree(): don't set ->mnt_mountpoint on the root of copy
constify mnt_has_parent()
pnode: lift peers() into pnode.h
new predicate: mount_is_ancestor()
constify is_local_mountpoint()
new predicate: anon_ns_root(mount)
dissolve_on_fput(): use anon_ns_root()
__attach_mnt(): lose the second argument
don't set MNT_LOCKED on parentless mounts
clone_mnt(): simplify the propagation-related logics
do_umount(): simplify the "is it still mounted" checks
sanitize handling of long-term internal mounts
Rewrite of propagate_umount()
make commit_tree() usable in same-namespace move case
attach_recursive_mnt(): unify the mnt_change_mountpoint() logics
attach_recursive_mnt(): pass destination mount in all cases
attach_recursive_mnt(): get rid of flags entirely
do_move_mount(): take dropping the old mountpoint into attach_recursive_mnt()
do_move_mount(): get rid of 'attached' flag
attach_recursive_mnt(): remove from expiry list on move
take ->mnt_expire handling under mount_lock [read_seqlock_excl]
pivot_root(): reorder tree surgeries, collapse unhash_mnt() and put_mountpoint()
combine __put_mountpoint() with unhash_mnt()
get rid of mountpoint->m_count
don't have mounts pin their parents
mount: separate the flags accessed only under namespace_sem
propagate_one(): get rid of dest_master
propagate_mnt(): handle all peer groups in the same loop
propagate_one(): separate the "do we need secondary here?" logics
propagate_one(): separate the "what should be the master for this copy" part
propagate_one(): fold into the sole caller
fs/pnode.c: get rid of globals
propagate_mnt(): get rid of last_dest
propagate_mnt(): fix comment and convert to kernel-doc, while we are at it
change_mnt_propagation() cleanups, step 1
change_mnt_propagation(): do_make_slave() is a no-op unless IS_MNT_SHARED()
do_make_slave(): choose new master sanely
turn do_make_slave() into transfer_propagation()
mnt_slave_list/mnt_slave: turn into hlist_head/hlist_node
change_mnt_propagation(): move ->mnt_master assignment into MS_SLAVE case
copy_tree(): don't link the mounts via mnt_list
take freeing of emptied mnt_namespace to namespace_unlock()
get rid of CL_SHARE_TO_SLAVE
invent_group_ids(): zero ->mnt_group_id always implies !IS_MNT_SHARED()
statmount_mnt_basic(): simplify the logics for group id
Documentation/filesystems/propagate_umount.txt | 484 +++++++++++++++++
drivers/gpu/drm/i915/gem/i915_gemfs.c | 21 +-
drivers/gpu/drm/v3d/v3d_gemfs.c | 21 +-
fs/hugetlbfs/inode.c | 2 +-
fs/mount.h | 40 +-
fs/namespace.c | 711 ++++++++++---------------
fs/pnode.c | 697 ++++++++++++------------
fs/pnode.h | 27 +-
include/linux/mount.h | 18 +-
ipc/mqueue.c | 2 +-
10 files changed, 1216 insertions(+), 807 deletions(-)
create mode 100644 Documentation/filesystems/propagate_umount.txt
