commit cf6620acc0f6fac57968aafef79ab372bdcf6157 upstream.

When the lock master processes a successful operation (request,
convert, cancel, or unlock), it will process the effects of the
change before sending the reply for the operation.  The "effects"
of the operation are:

- blocking callbacks (basts) for any newly granted locks
- waiting or converting locks that can now be granted

The cast is queued on the local node when the reply from the lock
master is received.  This means that a lock holder can receive a
bast for a lock mode that is doesn't yet know has been granted.

Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

commit 7fe2b3190b8b299409f13cf3a6f85c2bd371f8bb upstream.

When both blocking and completion callbacks are queued for lock,
the dlm would always deliver the completion callback (cast) first.
In some cases the blocking callback (bast) is queued before the
cast, though, and should be delivered first.  This patch keeps
track of the order in which they were queued and delivers them
in that order.

This patch also keeps track of the granted mode in the last cast
and eliminates the following bast if the bast mode is compatible
with the preceding cast mode.  This happens when a remotely mastered
lock is demoted, e.g. EX->NL, in which case the local node queues
a cast immediately after sending the demote message.  In this way
a cast can be queued for a mode, e.g. NL, that makes an in-transit
bast extraneous.

Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

commit 573c24c4af6664ffcd9aa7ba617a35fde2b95534 upstream.

Replace all GFP_KERNEL and ls_allocation with GFP_NOFS.
ls_allocation would be GFP_KERNEL for userland lockspaces
and GFP_NOFS for file system lockspaces.

It was discovered that any lockspaces on the system can
affect all others by triggering memory reclaim in the
file system which could in turn call back into the dlm
to acquire locks, deadlocking dlm threads that were
shared by all lockspaces, like dlm_recv.

Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

The code to set up sctp sockets was not using the sockfd_lookup()
and sockfd_put() routines to translate an fd to a socket.  The
direct fget and fput calls were resulting in error messages from
alloc_fd().

Also clean up two log messages and remove a third, related to
setting up sctp associations.

Signed-off-by: David Teigland <teigland@redhat.com>

The recently added dlm_lowcomms_connect_node() from
391fbdc5d527149578490db2f1619951d91f3561 does not work
when using SCTP instead of TCP.  The sctp connection code
has nothing to do without data to send.  Check for no data
in the sctp connection code and do nothing instead of
triggering a BUG.  Also have connect_node() do nothing
when the protocol is sctp.

Signed-off-by: David Teigland <teigland@redhat.com>

Make all seq_operations structs const, to help mitigate against
revectoring user-triggerable function pointers.

This is derived from the grsecurity patch, although generated from scratch
because it's simpler than extracting the changes from there.

Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/dlm:
  dlm: use kernel_sendpage
  dlm: fix connection close handling
  dlm: fix double-release of socket in error exit path

Using kernel_sendpage() is cleaner and safer than following
sock->ops ourselves.

Signed-off-by: Paolo Bonzini <bonzini@gnu.org>
Signed-off-by: David Teigland <teigland@redhat.com>

Closing a connection to a node can create problems if there are
outstanding messages for that node.  The problems include dlm_send
spinning attempting to reconnect, or BUG from tcp_connect_to_sock()
attempting to use a partially closed connection.

To cleanly close a connection, we now first attempt to send any pending
messages, cancel any remaining workqueue work, and flag the connection
as closed to avoid reconnect attempts.

Signed-off-by: Lars Marowsky-Bree <lmb@suse.de>
Signed-off-by: Christine Caulfield <ccaulfie@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>

The last correction to the tcp_connect_to_sock error exit path,
commit a89d63a159b1ba5833be2bef00adf8ad8caac8be, can free an already
freed socket, due to collision with a previous (incomplete) attempt
to fix the same issue, commit 311f6fc77c51926dbdfbeab0a5d88d70f01fa3f4.

Signed-off-by: Casey Dahlin <cdahlin@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>