* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
  rbd: fix safety of rbd_put_client()
  rbd: fix a memory leak in rbd_get_client()
  ceph: create a new session lock to avoid lock inversion
  ceph: fix length validation in parse_reply_info()
  ceph: initialize client debugfs outside of monc->mutex
  ceph: change "ceph.layout" xattr to be "ceph.file.layout"

Lockdep was reporting a possible circular lock dependency in
dentry_lease_is_valid().  That function needs to sample the
session's s_cap_gen and and s_cap_ttl fields coherently, but needs
to do so while holding a dentry lock.  The s_cap_lock field was
being used to protect the two fields, but that can't be taken while
holding a lock on a dentry within the session.

In most cases, the s_cap_gen and s_cap_ttl fields only get operated
on separately.  But in three cases they need to be updated together.
Implement a new lock to protect the spots updating both fields
atomically is required.

Signed-off-by: Alex Elder <elder@dreamhost.com>
Reviewed-by: Sage Weil <sage@newdream.net>

"len" is read from network and thus needs validation.  Otherwise, given
a bogus "len" value, p+len could be an out-of-bounds pointer, which is
used in further parsing.

Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Sage Weil <sage@newdream.net>

The virtual extended attribute named "ceph.layout" is meaningful
only for regular files.  Change its name to be "ceph.file.layout" to
more directly reflect that in the ceph xattr namespace.  Preserve
the old "ceph.layout" name for the time being (until we decide it's
safe to get rid of it entirely).

Add a missing initializer for "readonly" in the terminating entry.

Signed-off-by: Alex Elder <elder@dreamhost.com>
Reviewed-by: Sage Weil <sage@newdream.net>

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
  ceph: ensure prealloc_blob is in place when removing xattr
  rbd: initialize snap_rwsem in rbd_add()
  ceph: enable/disable dentry complete flags via mount option
  vfs: export symbol d_find_any_alias()
  ceph: always initialize the dentry in open_root_dentry()
  libceph: remove useless return value for osd_client __send_request()
  ceph: avoid iput() while holding spinlock in ceph_dir_fsync
  ceph: avoid useless dget/dput in encode_fh
  ceph: dereference pointer after checking for NULL
  crush: fix force for non-root TAKE
  ceph: remove unnecessary d_fsdata conditional checks
  ceph: Use kmemdup rather than duplicating its implementation

Fix up conflicts in fs/ceph/super.c (d_alloc_root() failure handling vs
always initialize the dentry in open_root_dentry)

In __ceph_build_xattrs_blob(), if a ceph inode's extended attributes
are marked dirty, all attributes recorded in its rb_tree index are
formatted into a "blob" buffer.  The target buffer is recorded in
ceph_inode->i_xattrs.prealloc_blob, and it is expected to exist and
be of sufficient size to hold the attributes.

The extended attributes are marked dirty in two cases: when a new
attribute is added to the inode; or when one is removed.  In the
former case work is done to ensure the prealloc_blob buffer is
properly set up, but in the latter it is not.

Change the logic in ceph_removexattr() so it matches what is
done in ceph_setxattr().  Note that this is done in a way that
keeps the two blocks of code nearly identical, in anticipation
of a subsequent patch that encapsulates some of this logic into
one or more helper routines.

Signed-off-by: Alex Elder <elder@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>

Enable/disable use of the dentry dir 'complete' flag via a mount option.
This lets the admin control whether ceph uses the dcache to satisfy
negative lookups or readdir when it has the entire directory contents in
its cache.

This is purely a performance optimization; correctness is guaranteed
whether it is enabled or not.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sage Weil <sage@newdream.net>

When open_root_dentry() gets a dentry via d_obtain_alias() it does
not get initialized.  If the dentry obtained came from the cache,
this is OK.  But if not, the result is an improperly initialized
dentry.

To fix this, call ceph_init_dentry() regardless of which path
produced the dentry.  That function returns immediately for a dentry
that is already initialized, it is safe to use either way.

(Credit to Sage, who suggested this fix.)

Signed-off-by: Alex Elder <aelder@sgi.com>

ceph_mdsc_put_request() can call iput(), which can sleep.  Don't do that.

Fixes: #1812
Signed-off-by: Sage Weil <sage@newdream.net>

Nothing we do here sleeps, so just do it under d_lock and avoid the dget/
dput entirely.

Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Sage Weil <sage@newdream.net>