The bast mode that appears in the debugfs output should be
useful on both master and process nodes. lkb_highbast is
currently printed, and is only useful on the master node.
lkb_bastmode is only useful on the process node. This
patch sets lkb_bastmode on the master node as well, and
uses that value in the debugfs print.
Signed-off-by: David Teigland <teigland@redhat.com>
Although it is possible to get this information from the path,
its much easier to provide the lockspace as a seperate env
variable.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
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>
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>
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>
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
391fbdc5d5 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 a89d63a159, can free an already
freed socket, due to collision with a previous (incomplete) attempt
to fix the same issue, commit 311f6fc77c.
Signed-off-by: Casey Dahlin <cdahlin@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
In the tcp_connect_to_sock() error exit path, the socket
allocated at the top of the function was not being freed.
Signed-off-by: Casey Dahlin <cdahlin@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
This makes generic netlink network namespace aware. No
generic netlink families except for the controller family
are made namespace aware, they need to be checked one by
one and then set the family->netnsok member to true.
A new function genlmsg_multicast_netns() is introduced to
allow sending a multicast message in a given namespace,
for example when it applies to an object that lives in
that namespace, a new function genlmsg_multicast_allns()
to send a message to all network namespaces (for objects
that do not have an associated netns).
The function genlmsg_multicast() is changed to multicast
the message in just init_net, which is currently correct
for all generic netlink families since they only work in
init_net right now. Some will later want to work in all
net namespaces because they do not care about the netns
at all -- those will have to be converted to use one of
the new functions genlmsg_multicast_allns() or
genlmsg_multicast_netns() whenever they are made netns
aware in some way.
After this patch families can easily decide whether or
not they should be available in all net namespaces. Many
genl families us it for objects not related to networking
and should therefore be available in all namespaces, but
that will have to be done on a per family basis.
Note that this doesn't touch on the checkpoint/restart
problem where network namespaces could be used, genl
families and multicast groups are numbered globally and
I see no easy way of changing that, especially since it
must be possible to multicast to all network namespaces
for those families that do not care about netns.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix a regression from the original addition of nfs lock support
586759f03e. When a synchronous
(non-nfs) plock completes, the waiting thread will wake up and
free the op struct. This races with the user thread in
dev_write() which goes on to read the op's callback field to
check if the lock is async and needs a callback. This check
can happen on the freed op. The fix is to note the callback
value before the op can be freed.
Signed-off-by: David Teigland <teigland@redhat.com>
CC [M] fs/dlm/lock.o
fs/dlm/lock.c: In function ‘find_rsb’:
fs/dlm/lock.c:438: warning: ‘r’ may be used uninitialized in this function
Since r is used on the error path to set r_ret, set it to NULL.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
Change some GFP_KERNEL allocations to use either GFP_NOFS or
ls_allocation (when available) which the fs sets to GFP_NOFS.
The point is to prevent allocations from going back into the
cluster fs in places where that might lead to deadlock.
Signed-off-by: David Teigland <teigland@redhat.com>
Make network connections to other nodes earlier, in the context of
dlm_recoverd. This avoids connecting to nodes from dlm_send where we
try to avoid allocations which could possibly deadlock if memory reclaim
goes into the cluster fs which may try to do a dlm operation.
Signed-off-by: Christine Caulfield <ccaulfie@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
When a lockspace was joined multiple times, the global dlm
use count was incremented when it should not have been. This
caused the global dlm threads to not be stopped when all
lockspaces were eventually be removed.
Signed-off-by: David Teigland <teigland@redhat.com>
Using offsetof() to calculate name length does not work because
it does not produce consistent results with with structure packing.
This caused memcpy to corrupt memory by copying 4 extra bytes off
the end of the buffer on 64 bit kernels with 32 bit userspace
(the only case where this 32/64 compat code is used).
The fix is to calculate name length directly from the start instead
of trying to derive it later using count and offsetof.
Signed-off-by: David Teigland <teigland@redhat.com>
Return immediately from dlm_unlock(CANCEL) if the lock is
granted and not being converted; there's nothing to cancel.
Signed-off-by: David Teigland <teigland@redhat.com>
