Add a function that can be used through libdlm by a system daemon to cancel
another process's deadlocked lock. A completion ast with EDEADLK is returned
to the process waiting for the lock.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Change the user/kernel device interface used by libdlm:
- Add ability for userspace to check the version of the interface. libdlm
can now adapt to different versions of the kernel interface.
- Increase the size of the flags passed in a lock request so all possible
flags can be used from userspace.
- Add an opaque "xid" value for each lock. This "transaction id" will be
used later to associate locks with each other during deadlock detection.
- Add a "timeout" value for each lock. This is used along with the
DLM_LKF_TIMEOUT flag.
Also, remove a fragment of unused code in device_read().
This patch requires updating libdlm which is backward compatible with
older kernels.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Add code to accept purge commands from userland.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Here's a patch which add 32/64 bit compat to the DLM IOs and tidies the
structures for alignment.
As it causes an ABI change I had few qualms about adding the extra flag for
"is64bit" as it simply uses a byte that would have been padding.
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch removes support for range locking from the DLM
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This is the core of the distributed lock manager which is required
to use GFS2 as a cluster filesystem. It is also used by CLVM and
can be used as a standalone lock manager independantly of either
of these two projects.
It implements VAX-style locking modes.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steve Whitehouse <swhiteho@redhat.com>
