Pass perm to v9fs_vfs_mkspecial() instead of passing mode;
calculate in caller when done for mknod(), use known value for link()
and symlink().  As the result, we avoid a bit of work *and* stop
mixing mode_t with P9_DMLINK.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

it's a just a wrapper for vfs_create()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

both proc_dir_entry ->mode and populating functions
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

both callers of device_get_devnode() are only interested in lower 16bits
and nobody tries to return anything wider than 16bit anyway.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

... rather than open-coding it
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

vfs_create() ignores everything outside of 16bit subset of its
mode argument; switching it to umode_t is obviously equivalent
and it's the only caller of the method
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

vfs_mkdir() gets int, but immediately drops everything that might not
fit into umode_t and that's the only caller of ->mkdir()...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

unfortunately, just checking MS_BORN after having grabbed ->s_umount in
sget() is not enough; places that pick superblock from a list and
grab s_umount shared need the same check in addition to checking for
->s_root; otherwise three-way race between failing mount, sget() and
such list-walker can leave us with list-walker coming *second*, when
temporary active ref grabbed by sget() (to be dropped when sget()
notices that original mount has failed by checking MS_BORN) has
lead to deactivate_locked_super() from failing ->mount() *not* doing
->kill_sb() and just releasing ->s_umount.  Once sget() gets through
and notices that MS_BORN had never been set it will drop the active
ref and fs will be shut down and kicked out of all lists, but it's
too late for something like sync_supers().
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

... and bury user_get_super()/statfs_by_dentry() - they are
purely internal now.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

... and clean it up a bit, while we are at it
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

... so no exitcalls there.  Not much would work if pipe(2) would stop
working, after all...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Seeing that just about every destructor got that INIT_LIST_HEAD() copied into
it, there is no point whatsoever keeping this INIT_LIST_HEAD in inode_init_once();
the cost of taking it into inode_init_always() will be negligible for pipes
and sockets and negative for everything else.  Not to mention the removal of
boilerplate code from ->destroy_inode() instances...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

new helper (wrapper around mnt_drop_write()) to be used in pair with
mnt_want_write_file().
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

the only user outside of fs/namespace.c has died
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

... rather than duplicating that in callers
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

it's not needed anymore; we used to, back when we had to do
mount_subtree() by hand, complete with put_mnt_ns() in it.
No more...  Apparmor didn't need it since the __d_path() fix.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

tomoyo/realpath.c needs exactly one include - that of common.h.  It pulls
everything the thing needs, without doing ridiculous garbage such as trying
to include ../../fs/internal.h.  If that alone doesn't scream "layering
violation", I don't know what does; and these days it's all for nothing,
since it fortunately does not use any symbols defined in there...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

lose it
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

a) mount --move is checking that ->mnt_parent is non-NULL before
looking if that parent happens to be shared; ->mnt_parent is never
NULL and it's not even an misspelled !mnt_has_parent()

b) pivot_root open-codes is_path_reachable(), poorly.

c) so does path_is_under(), while we are at it.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

vfsmounts have ->mnt_parent pointing either to a different vfsmount
or to itself; it's never NULL and termination condition in loops
traversing the tree towards root is mnt == mnt->mnt_parent.  At least
one place (see the next patch) is confused about what's going on;
let's add an explicit helper checking it right way and use it in
all places where we need it.  Not that there had been too many,
but...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

mnt_{inc,dec}_count() is not cleaner than doing the corresponding
mnt_add_count() directly and mnt_set_count() is not used at all.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

A bunch of places in nfsd does mnt_{want,drop}_write on vfsmount of
export of given fhandle.  Switched to obvious inlined helpers...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

it's both faster (in case when file has been opened for write) and cleaner.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

some stuff in there can actually become static; some belongs to pnode.h
as it's a private interface between namespace.c and pnode.c...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

No need to duplicate them in both callers; make it return
ERR_PTR(-ENOMEM) on allocation failure instead of NULL and
it'll be able to report rpc_lookup_cred() failures just
fine.  Callers are much happier that way...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>