* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (23 commits)
  ceph: document unlocked d_parent accesses
  ceph: explicitly reference rename old_dentry parent dir in request
  ceph: document locking for ceph_set_dentry_offset
  ceph: avoid d_parent in ceph_dentry_hash; fix ceph_encode_fh() hashing bug
  ceph: protect d_parent access in ceph_d_revalidate
  ceph: protect access to d_parent
  ceph: handle racing calls to ceph_init_dentry
  ceph: set dir complete frag after adding capability
  rbd: set blk_queue request sizes to object size
  ceph: set up readahead size when rsize is not passed
  rbd: cancel watch request when releasing the device
  ceph: ignore lease mask
  ceph: fix ceph_lookup_open intent usage
  ceph: only link open operations to directory unsafe list if O_CREAT|O_TRUNC
  ceph: fix bad parent_inode calc in ceph_lookup_open
  ceph: avoid carrying Fw cap during write into page cache
  libceph: don't time out osd requests that haven't been received
  ceph: report f_bfree based on kb_avail rather than diffing.
  ceph: only queue capsnap if caps are dirty
  ceph: fix snap writeback when racing with writes
  ...

For the most part we don't care about racing with rename when directing
MDS requests; either the old or new parent is fine.  Document that, and
do some minor cleanup.

Reviewed-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>

We carry a pin on the parent directory for the rename source and dest
dentries.  For the source it's r_locked_dir; we need to explicitly
reference the old_dentry parent as well, since the dentry's d_parent may
change between when the request was created and pinned and when it is
freed.

Reviewed-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>

Reviewed-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>

Have caller pass in a safely-obtained reference to the parent directory
for calculating a dentry's hash valud.

While we're here, simpify the flow through ceph_encode_fh() so that there
is a single exit point and cleanup.

Also fix a bug with the dentry hash calculation: calculate the hash for the
dentry we were given, not its parent.

Reviewed-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>

Protect d_parent with d_lock.  Carry a reference.  Simplify the flow so
that there is a single exit point and cleanup.

Reviewed-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>

d_parent is protected by d_lock: use it when looking up a dentry's parent
directory inode.  Also take a reference and drop it in the caller to avoid
a use-after-free.

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

The ->lookup() and prepopulate_readdir() callers are working with unhashed
dentries, so we don't have to worry.  The export.c callers, though, need
to initialize something they got back from d_obtain_alias() and are
potentially racing with other callers.  Make sure we don't return unless
the dentry is properly initialized (by us or someone else).

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

Curretly ceph_add_cap clears the complete bit if we are newly issued the
FILE_SHARED cap, which is normally the case for a newly issue cap on a new
directory.  That means we clear the just-set bit.  Move the check that sets
the flag to after the cap is added/updated.

Reviewed-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>

This should improve the default read performance, as without it
readahead is practically disabled.

Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>