procfs inodes need only the ns_ops part; nsfs inodes don't need it at all
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

New pseudo-filesystem: nsfs.  Targets of /proc/*/ns/* live there now.
It's not mountable (not even registered, so it's not in /proc/filesystems,
etc.).  Files on it *are* bindable - we explicitly permit that in do_loopback().

This stuff lives in fs/nsfs.c now; proc_ns_fget() moved there as well.
get_proc_ns() is a macro now (it's simply returning ->i_private; would
have been an inline, if not for header ordering headache).
proc_ns_inode() is an ex-parrot.  The interface used in procfs is
ns_get_path(path, task, ops) and ns_get_name(buf, size, task, ops).

Dentries and inodes are never hashed; a non-counting reference to dentry
is stashed in ns_common (removed by ->d_prune()) and reused by ns_get_path()
if present.  See ns_get_path()/ns_prune_dentry/nsfs_evict() for details
of that mechanism.

As the result, proc_ns_follow_link() has stopped poking in nd->path.mnt;
it does nd_jump_link() on a consistent <vfsmount,dentry> pair it gets
from ns_get_path().
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

a) make get_proc_ns() return a pointer to struct ns_common
b) mirror ns_ops in dentry->d_fsdata of ns dentries, so that
is_mnt_ns_file() could get away with fewer dereferences.

That way struct proc_ns becomes invisible outside of fs/proc/*.c
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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

take struct ns_common *, for now simply wrappers around proc_{alloc,free}_inum()
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

We can do that now.  And kill ->inum(), while we are at it - all instances
are identical.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Acked-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

for now - just move corresponding ->proc_inum instances over there
Acked-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Check against !OVL_PATH_LOWER instead of OVL_PATH_MERGE.  For a copied up
directory the two are currently equivalent.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>

Pass dentry into ovl_dir_read_merged() insted of upperpath and lowerpath.
This cleans up callers and paves the way for multi-layer directory reads.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>

Don't open code lockless_dereference() in ovl_upperdentry_dereference().
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>

Allow option separator (comma) to be escaped with backslash.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>

Xattr operations can race with copy up.  This does not matter as long as
we consistently fiter out "trunsted.overlay.opaque" attribute on upper
directories.

Previously we checked parent against OVL_PATH_MERGE.  This is too general,
and prone to race with copy-up.  I.e. we found the parent to be on the
lower layer but ovl_dentry_real() would return the copied-up dentry,
possibly with the "opaque" attribute.

So instead use ovl_path_real() and decide to filter the attributes based on
the actual type of the dentry we'll use.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>

ovl_remove_and_whiteout() needs to check if upper dentry exists or not
after having locked upper parent directory.

Previously we used a "type" value computed before locking the upper parent
directory, which is susceptible to racing with copy-up.

There's a similar check in ovl_check_empty_and_clear().  This one is not
actually racy, since copy-up doesn't change the "emptyness" property of a
directory.  Add a comment to this effect, and check the existence of upper
dentry locally to make the code cleaner.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>

Some distributions carry an "old" format of overlayfs while mainline has a
"new" format.

The distros will possibly want to keep the old overlayfs alongside the new
for compatibility reasons.

To make it possible to differentiate the two versions change the name of
the new one from "overlayfs" to "overlay".
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Reported-by: NSerge Hallyn <serge.hallyn@ubuntu.com>
Cc: Andy Whitcroft <apw@canonical.com>

The fair reader/writer locks mean that btrfs_clear_path_blocking needs
to strictly follow lock ordering rules even when we already have
blocking locks on a given path.

Before we can clear a blocking lock on the path, we need to make sure
all of the locks have been converted to blocking.  This will remove lock
inversions against anyone spinning in write_lock() against the buffers
we're trying to get read locks on.  These inversions didn't exist before
the fair read/writer locks, but now we need to be more careful.

We papered over this deadlock in the past by changing
btrfs_try_read_lock() to be a true trylock against both the spinlock and
the blocking lock.  This was slower, and not sufficient to fix all the
deadlocks.  This patch adds a btrfs_tree_read_lock_atomic(), which
basically means get the spinlock but trylock on the blocking lock.
Signed-off-by: NChris Mason <clm@fb.com>
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Reported-by: NPatrick Schmid <schmid@phys.ethz.ch>
cc: stable@vger.kernel.org #v3.15+

With the isofs_hash() function removed, isofs_hash_ms() is the only user
of isofs_hash_common(), but it's defined inside of an #ifdef, which triggers
this gcc warning in ARM axm55xx_defconfig starting with v3.18-rc3:

fs/isofs/inode.c:177:1: warning: 'isofs_hash_common' defined but not used [-Wunused-function]

This patch moves the function inside of the same #ifdef section to avoid that
warning, which seems the best compromise of a relatively harmless patch for
a late -rc.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Fixes: b0afd8e5 ("isofs: don't bother with ->d_op for normal case")
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

In "d_prune_alias(): just lock the parent and call __dentry_kill()" the old
dget + d_drop + dput has been replaced with lock_parent + __dentry_kill;
unfortunately, dput() does more than just killing dentry - it also drops the
reference to parent.  New variant leaks that reference and needs dput(parent)
after killing the child off.
Signed-off-by: NYan, Zheng <zyan@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

This patch fixes kmemcheck warning in switch_names. The function
switch_names swaps inline names of two dentries. It swaps full arrays
d_iname, no matter how many bytes are really used by the strings. Reading
data beyond string ends results in kmemcheck warning.

We fix the bug by marking both arrays as fully initialized.
Signed-off-by: NMikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org # v3.15
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

... for situations when we don't have any candidate in pathnames - basically,
in descriptor-based syscalls.

[Folded the build fix for !CONFIG_AUDITSYSCALL configs from Chen Gang]
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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

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

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

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

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

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

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

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

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

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

... to get from opened file on nfsctl to relevant struct net *
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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

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

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

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

In ->atomic_open(inode, dentry, file, opened) calling finish_no_open(file, NULL)
is equivalent to dget(dentry); return finish_no_open(file, dentry);

No need to open-code that...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

dentry is always hashed and negative, inode - non-error, non-NULL and
non-directory.  In such conditions d_splice_alias() is equivalent to
"d_instantiate(dentry, inode) and return NULL", which simplifies the
downstream code and is consistent with the "have to create a new object"
case.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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

fsnotify() needs to merge inode and mount marks lists when notifying
groups about events so that ignore masks from inode marks are reflected
in mount mark notifications and groups are notified in proper order
(according to priorities).

Currently the sorting of the lists done by fsnotify_add_inode_mark() /
fsnotify_add_vfsmount_mark() and fsnotify() differed which resulted
ignore masks not being used in some cases.

Fix the problem by always using the same comparison function when
sorting / merging the mark lists.

Thanks to Heinrich Schuchardt for improvements of my patch.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=87721Signed-off-by: NJan Kara <jack@suse.cz>
Reported-by: NHeinrich Schuchardt <xypron.glpk@gmx.de>
Tested-by: NHeinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

TID of cap flush ack is 64 bits, but ceph_inode_info::flushing_cap_tid
is only 16 bits. 16 bits should be plenty to let the cap flush updates
pipeline appropriately, but we need to cast in the proper direction when
comparing these differently-sized versions. So downcast the 64-bits one
to 16 bits.

Reflects ceph.git commit a5184cf46a6e867287e24aeb731634828467cd98.
Signed-off-by: NYan, Zheng <zyan@redhat.com>
Reviewed-by: NIlya Dryomov <idryomov@redhat.com>