This patch addresses a problem introduced with the last round of
lowcomms patches where the 'othercon' connections do not get freed when
the DLM shuts down.
This results in the error message
"slab error in kmem_cache_destroy(): cache `dlm_conn': Can't free all
objects"
and the DLM cannot be restarted without a system reboot.
See bz#428119
Signed-off-by: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Fabio M. Di Nitto <fabbione@ubuntu.com>
Signed-off-by: David Teigland <teigland@redhat.com>
The dlm functions in memory.c should use the dlm_ prefix. Also, use
kzalloc/kfree directly for dlm_direntry's, removing the wrapper functions.
Signed-off-by: David Teigland <teigland@redhat.com>
Change log_error() to log_debug() for conditions that can occur in
large number in normal operation.
Signed-off-by: David Teigland <teigland@redhat.com>
This patch adds a proper prototype for some functions in
fs/dlm/dlm_internal.h
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: David Teigland <teigland@redhat.com>
A common problem occurs when multiple IP addresses within the same
subnet are assigned to the same NIC. If we make a connection attempt to
another address on the same subnet as one of those addresses, the
connection attempt will not necessarily be routed from the address we
want.
In the case of the DLM, the other nodes will quickly drop the connection
attempt, causing problems.
This patch makes the DLM bind to the local address it acquired from the
cluster manager when using TCP prior to making a connection, obviating
the need for administrators to "fix" their systems or use clever routing
tricks.
Signed-off-by: Lon Hohberger <lhh@redhat.com>
Signed-off-by: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
There is no need for kobject_unregister() anymore, thanks to Kay's
kobject cleanup changes, so replace all instances of it with
kobject_put().
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Stop using kobject_register, as this way we can control the sending of
the uevent properly, after everything is properly initialized.
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
kernel_kset does not need to be a kset, but a much simpler kobject now
that we have kobj_attributes.
We also rename kernel_kset to kernel_kobj to catch all users of this
symbol with a build error instead of an easy-to-ignore build warning.
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Dynamically create the kset instead of declaring it statically. We also
rename kernel_subsys to kernel_kset to catch all users of this symbol
with a build error instead of an easy-to-ignore build warning.
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Dynamically create the kset instead of declaring it statically.
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
We don't need a "default" ktype for a kset. We should set this
explicitly every time for each kset. This change is needed so that we
can make ksets dynamic, and cleans up one of the odd, undocumented
assumption that the kset/kobject/ktype model has.
This patch is based on a lot of help from Kay Sievers.
Nasty bug in the block code was found by Dave Young
<hidave.darkstar@gmail.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Dave Young <hidave.darkstar@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The task_struct->pid member is going to be deprecated, so start
using the helpers (task_pid_nr/task_pid_vnr/task_pid_nr_ns) in
the kernel.
The first thing to start with is the pid, printed to dmesg - in
this case we may safely use task_pid_nr(). Besides, printks produce
more (much more) than a half of all the explicit pid usage.
[akpm@linux-foundation.org: git-drm went and changed lots of stuff]
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Dave Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Changes NLS and DLM menus into a 'menuconfig' object so that it can be
disabled at once without having to enter the menu first to disable the config
option.
Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6: (75 commits)
PM: merge device power-management source files
sysfs: add copyrights
kobject: update the copyrights
kset: add some kerneldoc to help describe what these strange things are
Driver core: rename ktype_edd and ktype_efivar
Driver core: rename ktype_driver
Driver core: rename ktype_device
Driver core: rename ktype_class
driver core: remove subsystem_init()
sysfs: move sysfs file poll implementation to sysfs_open_dirent
sysfs: implement sysfs_open_dirent
sysfs: move sysfs_dirent->s_children into sysfs_dirent->s_dir
sysfs: make sysfs_root a regular directory dirent
sysfs: open code sysfs_attach_dentry()
sysfs: make s_elem an anonymous union
sysfs: make bin attr open get active reference of parent too
sysfs: kill unnecessary NULL pointer check in sysfs_release()
sysfs: kill unnecessary sysfs_get() in open paths
sysfs: reposition sysfs_dirent->s_mode.
sysfs: kill sysfs_update_file()
...
A kset should not have its name set directly, so dynamically set the
name at runtime.
This is needed to remove the static array in the kobject structure which
will be changed in a future patch.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Introduce a per-lockspace rwsem that's held in read mode by dlm_recv
threads while working in the dlm. This allows dlm_recv activity to be
suspended when the lockspace transitions to, from and between recovery
cycles.
The specific bug prompting this change is one where an in-progress
recovery cycle is aborted by a new recovery cycle. While dlm_recv was
processing a recovery message, the recovery cycle was aborted and
dlm_recoverd began cleaning up. dlm_recv decremented recover_locks_count
on an rsb after dlm_recoverd had reset it to zero. This is fixed by
suspending dlm_recv (taking write lock on the rwsem) before aborting the
current recovery.
The transitions to/from normal and recovery modes are simplified by using
this new ability to block dlm_recv. The switch from normal to recovery
mode means dlm_recv goes from processing locking messages, to saving them
for later, and vice versa. Races are avoided by blocking dlm_recv when
setting the flag that switches between modes.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
If the castaddr passed to the userland API is NULL then don't overwrite the
existing castparam. This allows a different thread to cancel a lock request and
the CANCEL AST gets delivered to the original thread.
bz#306391 (for RHEL4) refers.
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Under high recovery loads dlm_sendd can monopolise the CPU and cause soft lockups.
This one extra and one moved cond_resched() make it yield a little more during
such times keeping work moving.
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch fixes the slight mess made in lowcomms closing by previous patches
and fixes all sorts of DLM hangs.
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Fix a long standing bug where a blocking callback would be missed
when there's a granted lock in PR mode and waiting locks in both
PR and CW modes (and the PR lock was added to the waiting queue
before the CW lock). The logic simply compared the numerical values
of the modes to determine if a blocking callback was required, but in
the one case of PR and CW, the lower valued CW mode blocks the higher
valued PR mode. We just need to add a special check for this PR/CW
case in the tests that decide when a blocking callback is needed.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
The last patch to clean out 'othercon' structures only fixed half the problem.
The attached addresses the other situations too, and fixes bz#238490
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
There's a memory leak in fs/dlm/member.c::dlm_add_member().
If "dlm_node_weight(ls->ls_name, nodeid)" returns < 0, then
we'll return without freeing the memory allocated to the (at
that point yet unused) 'memb'.
This patch frees the allocated memory in that case and thus
avoids the leak.
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
When we build a sockaddr_storage for an IP address, clear the unused parts as
they could be used for node comparisons.
I have seen this occasionally make sctp connections fail.
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Fix regression in recent patch "[DLM] variable allocation" which
attempts to dereference an "ls" struct when it's NULL.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch clears the othercon pointer and frees the memory when a connnection
is closed. This could cause a small memory leak when nodes leave the cluster.
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Slab destructors were no longer supported after Christoph's
c59def9f22 change. They've been
BUGs for both slab and slub, and slob never supported them
either.
This rips out support for the dtor pointer from kmem_cache_create()
completely and fixes up every single callsite in the kernel (there were
about 224, not including the slab allocator definitions themselves,
or the documentation references).
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Transform some calls to kmalloc/memset to a single kzalloc (or kcalloc).
Here is a short excerpt of the semantic patch performing
this transformation:
@@
type T2;
expression x;
identifier f,fld;
expression E;
expression E1,E2;
expression e1,e2,e3,y;
statement S;
@@
x =
- kmalloc
+ kzalloc
(E1,E2)
... when != \(x->fld=E;\|y=f(...,x,...);\|f(...,x,...);\|x=E;\|while(...) S\|for(e1;e2;e3) S\)
- memset((T2)x,0,E1);
@@
expression E1,E2,E3;
@@
- kzalloc(E1 * E2,E3)
+ kcalloc(E1,E2,E3)
[akpm@linux-foundation.org: get kcalloc args the right way around]
Signed-off-by: Yoann Padioleau <padator@wanadoo.fr>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Acked-by: Russell King <rmk@arm.linux.org.uk>
Cc: Bryan Wu <bryan.wu@analog.com>
Acked-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Dave Airlie <airlied@linux.ie>
Acked-by: Roland Dreier <rolandd@cisco.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Acked-by: Dmitry Torokhov <dtor@mail.ru>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Acked-by: Pierre Ossman <drzeus-list@drzeus.cx>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: "David S. Miller" <davem@davemloft.net>
Acked-by: Greg KH <greg@kroah.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Convert the su_sem member of struct configfs_subsystem to a struct
mutex, as that's what it is. Also convert all the users and update
Documentation/configfs.txt and Documentation/configfs_example.c
accordingly.
[ Conflict in fs/dlm/config.c with commit
3168b0780d manually resolved. --Mark ]
Inspired-by: Satyam Sharma <ssatyam@cse.iitk.ac.in>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
Configfs being based upon sysfs code, config_group_find_obj() is probably
so named because of the similar kset_find_obj() in sysfs. However,
"kobject"s in sysfs become "config_item"s in configfs, so let's call it
config_group_find_item() instead, for sake of uniformity, and make
corresponding change in the users of this function.
BTW a crucial difference between kset_find_obj and config_group_find_item
is in locking expectations. kset_find_obj does its locking by itself, but
config_group_find_item expects the *caller* to do the locking. The reason
for this: kset's have their own locks, config_group's don't but instead
rely on the subsystem mutex. And, subsystem needn't necessarily be around
when config_group_find_item() is called.
So let's state these locking semantics explicitly, and rectify the comment,
otherwise bugs could continue to occur in future, as they did in the past
(refer commit d82b8191e238 in gfs2-2.6-fixes.git).
[ I also took the opportunity to fix some bad whitespace and
double-empty lines. --Joel ]
[ Conflict in fs/dlm/config.c with commit
3168b0780d manually resolved. --Mark ]
Signed-off-by: Satyam Sharma <ssatyam@cse.iitk.ac.in>
Cc: David Teigland <teigland@redhat.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
fs/dlm/config.c contains a useful generic macro called __CONFIGFS_ATTR
that is similar to sysfs' __ATTR macro that makes defining attributes
easy for any user of configfs. Separate it out into configfs.h so that
other users (forthcoming in dynamic netconsole patchset) can use it too.
Signed-off-by: Satyam Sharma <ssatyam@cse.iitk.ac.in>
Cc: David Teigland <teigland@redhat.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
Add two more output fields (lkb_flags and rsb nodeid) to the new debugfs
file that dumps one lock per line. Also, dump all locks instead of just
mastered locks. Accordingly, use a suffix of _locks instead of _master.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch fixes Red Hat bz#245892
Opening a tcp connection from a cluster member to another cluster member
targeting the dlm port it is enough to stop every dlm operation in the cluster.
This means that GFS and rgmanager will hang.
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Mask off the recently added DLM_LSFL_FS flag when setting the exflags.
This way all the nodes in the lockspace aren't required to have the FS
flag set, since we later check that exflags matches among all nodes.
Signed-off-by: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Add a new flag, DLM_LSFL_FS, to be used when a file system creates a lockspace.
This flag causes the dlm to use GFP_NOFS for allocations instead of GFP_KERNEL.
(This updated version of the patch uses gfp_t for ls_allocation.)
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-Off-By: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This is a fix for the patch
021d2ff3a08019260a1dc002793c92d6bf18afb6
I left off a dlm_hold_rsb which causes the box to panic if you try to use
debugfs. This patch fixes the problem. Sorry about that,
Signed-off-by: Josef Bacik <jwhiter@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch clears the user_data of active sockets as part of cleanup.
This prevents any late-arriving data from trying to add jobs to the work
queue while we are tidying up.
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-Off-By: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Display the initial value of the "protocol" config value in configfs.
The default value has always been 0 in the past anyway, so it's always
appeared to be correct.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Add a new debugfs file that dumps a compact list of mastered locks.
This will be used by a userland daemon to collect state for deadlock
detection.
Also, for the existing function that prints all lock state, lock the rsb
before going through the lock lists since they can be changing in the
course of normal dlm activity.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
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>
Various fixes related to the new timeout feature:
- add_timeout() missed setting TIMEWARN flag on lkb's when the
TIMEOUT flag was already set
- clear_proc_locks should remove a dead process's locks from the
timeout list
- the end-of-life calculation for user locks needs to consider that
ETIMEDOUT is equivalent to -DLM_ECANCEL
- make initial default timewarn_cs config value visible in configfs
- change bit position of TIMEOUT_CANCEL flag so it's not copied to
a remote master node
- set timestamp on remote lkb's so a lock dump will display the time
they've been waiting
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
A one liner fix which got missed from the earlier patches.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Cc: Fabio Massimo Di Nitto <fabbione@ubuntu.com>
Cc: David Teigland <teigland@redhat.com>
In the rush to get the previous patch set sent, a compilation bug I fixed
shortly before sending somehow got clobbered, probably by a missed quilt
refresh or something.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Joining the lockspace should wait for the initial round of inter-node
config checks to complete before returning. This way, if there's a
configuration mismatch between the joining node and the existing nodes,
the join can fail and return an error to the application.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Fix the error path when exiting new_lockspace(). It was kfree'ing the
lockspace struct at the end, but that's only valid if it exits before
kobject_register occured. After kobject_register we have to let the
kobject do the freeing.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
When conversion deadlock is detected, cancel the conversion and return
EDEADLK to the application. This is a new default behavior where before
the dlm would allow the deadlock to exist indefinately.
The DLM_LKF_NODLCKWT flag can now be used in a conversion to prevent the
dlm from performing conversion deadlock detection/cancelation on it.
The DLM_LKF_CONVDEADLK flag can continue to be used as before to tell the
dlm to demote the granted mode of the lock being converted if it gets into
a conversion deadlock.
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>
New features: lock timeouts and time warnings. If the DLM_LKF_TIMEOUT
flag is set, then the request/conversion will be canceled after waiting
the specified number of centiseconds (specified per lock). This feature
is only available for locks requested through libdlm (can be enabled for
kernel dlm users if there's a use for it.)
If the new DLM_LSFL_TIMEWARN flag is set when creating the lockspace, then
a warning message will be sent to userspace (using genetlink) after a
request/conversion has been waiting for a given number of centiseconds
(configurable per node). The time warnings will be used in the future
to do deadlock detection in userspace.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Don't let dlm_scand run during recovery since it may try to do a resource
directory removal while the directory nodes are changing.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This problem was originally reported against GFS6.1, but the same issue exists
in upstream DLM. This patch keeps the rsb iterator assigning under the rsbtbl
list lock. Each time we process an rsb we grab a reference to it to make sure
it is not freed out from underneath us, and then put it when we get the next rsb
in the list or move onto another list.
Signed-off-by: Josef Bacik <jwhiter@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Fix two races in fs/dlm/config.c:
(1) Grab the configfs subsystem semaphore before calling
config_group_find_obj() in get_space(). This solves a potential race
between get_space() and concurrent mkdir(2) or rmdir(2).
(2) Grab a reference on the found config_item _while_ holding the configfs
subsystem semaphore in get_comm(), and not after it. This solves a
potential race between get_comm() and concurrent rmdir(2).
Signed-off-by: Satyam Sharma <ssatyam@cse.iitk.ac.in>
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
The dependency of DLM on SYSFS got lost in
commit 6ed7257b46 resulting in the
following compile error with CONFIG_DLM=y, CONFIG_SYSFS=n:
<-- snip -->
...
LD .tmp_vmlinux1
fs/built-in.o: In function `dlm_lockspace_init':
/home/bunk/linux/kernel-2.6/linux-2.6.22-rc6-mm1/fs/dlm/lockspace.c:231: undefined reference to `kernel_subsys'
fs/built-in.o: In function `configfs_init':
/home/bunk/linux/kernel-2.6/linux-2.6.22-rc6-mm1/fs/configfs/mount.c:143: undefined reference to `kernel_subsys'
make[1]: *** [.tmp_vmlinux1] Error 1
<-- snip -->
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We need to work on cleaning up the relationship between kobjects, ksets and
ktypes. The removal of 'struct subsystem' is the first step of this,
especially as it is not really needed at all.
Thanks to Kay for fixing the bugs in this patch.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Replace some printk with log_print, and fix some simple cases of lines
over 80. Also, return -ENOTCONN if lowcomms_start fails due to no local
IP address being available.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Fix a few range & initialization bugs in lowcomms.
- max_nodeid is really the highest nodeid encountered, so all loops must include
it in their iterations.
- clean dlm_local_count & connection_idr so we can do a clean restart.
- Remove a spurious BUG_ON
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
When you attempt to release a lockspace in DLM, it will hang trying to down a
semaphore that has already been downed. The attached patch fixes the problem.
Signed-off-by: Josef Bacik <jwhiter@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Cc: Patrick Caulfield <pcaulfie@redhat.com>
There are flags to enable two specialized features in the dlm:
1. CONVDEADLK causes the dlm to resolve conversion deadlocks internally by
changing the granted mode of locks to NL.
2. ALTPR/ALTCW cause the dlm to change the requested mode of locks to PR
or CW to grant them if the normal requested mode can't be granted.
GFS direct i/o exercises both of these features, especially when mixed
with buffered i/o. The dlm has problems with them.
The first problem is on the master node. If it demotes a lock as a part of
converting it, the actual step of converting the lock isn't being done
after the demotion, the lock is just left sitting on the granted queue
with a granted mode of NL. I think the mistaken assumption was that the
call to grant_pending_locks() would grant it, but that function naturally
doesn't look at locks on the granted queue.
The second problem is on the process node. If the master either demotes
or gives an altmode, the munging of the gr/rq modes is never done in the
process copy of the lock, leaving the master/process copies out of sync.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Every file should include the headers containing the prototypes for
it's global functions.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch consolidates the TCP & SCTP protocols for the DLM into a single file
and makes it switchable at run-time (well, at least before the DLM actually
starts up!)
For RHEL5 this patch requires Neil Horman's patch that expands the in-kernel
socket API but that has already been twice ACKed so it should be OK.
The patch adds a new lowcomms.c file that replaces the existing lowcomms-sctp.c
& lowcomms-tcp.c files.
Signed-off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch removes a redundant (and incorrect) assignment from compat_output
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
A lock id is a uint32 and is used as an opaque reference to the lock. For
userland apps, the lkid is passed up, through libdlm, as the return value
from a write() on the dlm device. This created a problem when the high
bit was 1, making the lkid look like an error. This is fixed by changing
how the lkid is composed. The low 16 bits identified the hash bucket for
the lock and the high 16 bits were a per-bucket counter (which eventually
hit 0x8000 causing the problem). These are simply swapped around; the
number of hash table buckets is far below 0x8000, making all lkid's
positive when viewed as signed.
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>
Add code for purging orphan locks. A process can also purge all of its
own non-orphan locks by passing a pid of zero. Code already exists for
processes to create persistent locks that become orphans when the process
exits, but the complimentary capability for another process to then purge
these orphans has been missing.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This splits the current create_message() function into two parts so that
later patches can call the new lower-level _create_message() function when
they don't have an rsb struct. No functional change in this patch.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Full cancel and force-unlock support. In the past, cancel and force-unlock
wouldn't work if there was another operation in progress on the lock. Now,
both cancel and unlock-force can overlap an operation on a lock, meaning there
may be 2 or 3 operations in progress on a lock in parallel. This support is
important not only because cancel and force-unlock are explicit operations
that an app can use, but both are used implicitly when a process exits while
holding locks.
Summary of changes:
- add-to and remove-from waiters functions were rewritten to handle situations
with more than one remote operation outstanding on a lock
- validate_unlock_args detects when an overlapping cancel/unlock-force
can be sent and when it needs to be delayed until a request/lookup
reply is received
- processing request/lookup replies detects when cancel/unlock-force
occured during the op, and carries out the delayed cancel/unlock-force
- manipulation of the "waiters" (remote operation) state of a lock moved under
the standard rsb mutex that protects all the other lock state
- the two recovery routines related to locks on the waiters list changed
according to the way lkb's are now locked before accessing waiters state
- waiters recovery detects when lkb's being recovered have overlapping
cancel/unlock-force, and may not recover such locks
- revert_lock (cancel) returns a value to distinguish cases where it did
nothing vs cases where it actually did a cancel; the cancel completion ast
should only be done when cancel did something
- orphaned locks put on new list so they can be found later for purging
- cancel must be called on a lock when making it an orphan
- flag user locks (ENDOFLIFE) at the end of their useful life (to the
application) so we can return an error for any further cancel/unlock-force
- we weren't setting COMP/BAST ast flags if one was already set, so we'd lose
either a completion or blocking ast
- clear an unread bast on a lock that's become unlocked
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Replacement patch to remove redundant code rather than moving it around.
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Currently if the lockspace removal fails the misc device associated with a
lockspace is left deleted. After that there is no way to access the orphaned
lockspace from userland.
This patch recreates the misc device if th dlm_release_lockspace fails. I
believe this is better than attempting to remove the lockspace first because
that leaves an unattached device lying around. The potential gap in which there
is no access to the lockspace between removing the misc device and recreating it
is acceptable ... after all the application is trying to remove it, and only new
users of the lockspace will be affected.
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
The length of the second element of the kvec array was not initialised before
being added to the first one. This could cause invalid lengths to be passed to
kernel_recvmsg
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Every file should include the headers containing the prototypes for
it's global functions.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Many struct file_operations in the kernel can be "const". Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data. In addition it'll catch accidental writes at compile time to
these shared resources.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Replace appropriate pairs of "kmem_cache_alloc()" + "memset(0)" with the
corresponding "kmem_cache_zalloc()" call.
Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Andi Kleen <ak@muc.de>
Cc: Roland McGrath <roland@redhat.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Greg KH <greg@kroah.com>
Acked-by: Joel Becker <Joel.Becker@oracle.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Jan Kara <jack@ucw.cz>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <jmorris@namei.org>
Cc: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch stops the dlm_recv workqueue from busy-waiting when a node
disconnects. This can cause soft lockup errors on debug systems and bad
performance generally.
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
A new lvb for a userland lock wasn't being initialized to zero.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
On Sun, Jan 28, 2007 at 11:08:18AM +0100, Jiri Slaby wrote:
> Andrew Morton napsal(a):
> >Temporarily at
> >
> > http://userweb.kernel.org/~akpm/2.6.20-rc6-mm1/
>
> Unable to select IPV6. Menuconfig doesn't offer it when INET is selected.
> When it's not it appears in the menu, but after state change it gets away.
> The same behaviour in xconfig, gconfig.
>
> $ mkdir ../a/tst
> $ make O=../a/tst menuconfig
> HOSTCC scripts/basic/fixdep
> [...]
> HOSTLD scripts/kconfig/mconf
> scripts/kconfig/mconf arch/i386/Kconfig
> Warning! Found recursive dependency: INET GFS2_FS_LOCKING_DLM SYSFS
> OCFS2_FS INET
>
> Maybe this is the problem?
Yes, patch below.
> regards,
cu
Adrian
<-- snip -->
This patch fixes a circular dependency by letting GFS2_FS_LOCKING_DLM
and DLM depend on instead of select SYSFS.
Since SYSFS depends on EMBEDDED this change shouldn't cause any problems
for users.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
With CONFIG_DLM=m, CONFIG_PROC_FS=n, and CONFIG_SYSFS=n, kernel build
fails with:
WARNING: "kernel_subsys" [fs/gfs2/locking/dlm/lock_dlm.ko] undefined!
WARNING: "kernel_subsys" [fs/dlm/dlm.ko] undefined!
WARNING: "kernel_subsys" [fs/configfs/configfs.ko] undefined!
make[1]: *** [__modpost] Error 1
make: *** [modules] Error 2
Since fs/dlm/lockspace.c and fs/gfs2/locking/dlm/sysfs.c use
kernel_subsys, they should either DEPEND on it or SELECT it.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
A long, complicated sequence of events, beginning with the RESEND flag not
being cleared on an lkb, can result in an unlock never completing.
- lkb on waiters list for remote lookup
- the remote node is both the dir node and the master node, so
it optimizes the lookup into a request and sends a request
reply back
- the request reply is saved on the requestqueue to be processed
after recovery
- recovery runs dlm_recover_waiters_pre() which sets RESEND flag
so the lookup will be resent after recovery
- end of recovery: process_requestqueue takes saved request reply
which removes the lkb off the waitesr list, _without_ clearing
the RESEND flag
- end of recovery: dlm_recover_waiters_post() doesn't do anything
with the now completed lookup lkb (would usually clear RESEND)
- later, the node unmounts, unlocks this lkb that still has RESEND
flag set
- the lkb is on the waiters list again, now for unlock, when recovery
occurs, dlm_recover_waiters_pre() shows the lkb for unlock with RESEND
set, doesn't do anything since the master still exists
- end of recovery: dlm_recover_waiters_post() takes this lkb off
the waiters list because it has the RESEND flag set, then reports
an error because unlocks are never supposed to be handled in
recover_waiters_post().
- later, the unlock reply is received, doesn't find the lkb on
the waiters list because recover_waiters_post() has wrongly
removed it.
- the unlock operation has been lost, and we're left with a
stray granted lock
- unmount spins waiting for the unlock to complete
The visible evidence of this problem will be a node where gfs umount is
spinning, the dlm waiters list will be empty, and the dlm locks list will
show a granted lock.
The fix is simply to clear the RESEND flag when taking an lkb off the
waiters list.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
dlm_receive_message() returns 0 instead of returning 'error'. What would
happen is that process_requestqueue would take a saved message off the
requestqueue and call receive_message on it. receive_message would then
see that recovery had been aborted, set error to EINTR, and 'goto out',
expecting that the error would be returned. Instead, 0 was always
returned, so process_requestqueue would think that the message had been
processed and delete it instead of saving it to process next time. This
means the message (usually an unlock in my tests) would be lost.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Now that there can be multiple dlm_recv threads running we need to prevent two
recvs running for the same connection - it's unlikely but it can happen and it
causes message corruption.
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch fixes a bug whereby data on a newly accepted connection would be
ignored if it arrived soon after the accept.
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch removes some redundant fields from the connection structure and adds
some lockdep annotation to remove spurious warnings.
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
If master recovery happens on an rsb in one recovery sequence, then that
sequence is aborted before lock recovery happens, then in the next
sequence, we rely on the previous master recovery (which may now be
invalid due to another node ignoring a lookup result) and go on do to the
lock recovery where we get stuck due to an invalid master value.
recovery cycle begins: master of rsb X has left
nodes A and B send node C an rcom lookup for X to find the new master
C gets lookup from B first, sets B as new master, and sends reply back to B
C gets lookup from A next, and sends reply back to A saying B is master
A gets lookup reply from C and sets B as the new master in the rsb
recovery cycle on A, B and C is aborted to start a new recovery
B gets lookup reply from C and ignores it since there's a new recovery
recovery cycle begins: some other node has joined
B doesn't think it's the master of X so it doesn't rebuild it in the directory
C looks up the master of X, no one is master, so it becomes new master
B looks up the master of X, finds it's C
A believes that B is the master of X, so it sends its lock to B
B sends an error back to A
A resends
this repeats forever, the incorrect master value on A is never corrected
The fix is to do master recovery on an rsb that still has the NEW_MASTER
flag set from an earlier recovery sequence, and therefore didn't complete
lock recovery.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
When a user process exits, we clear all the locks it holds. There is a
problem, though, with locks that the process had begun unlocking before it
exited. We couldn't find the lkb's that were in the process of being
unlocked remotely, to flag that they are DEAD. To solve this, we move
lkb's being unlocked onto a new list in the per-process structure that
tracks what locks the process is holding. We can then go through this
list to flag the necessary lkb's when clearing locks for a process when it
exits.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch converts the DLM TCP lowcomms to use workqueues rather than using its
own daemon functions. Simultaneously removing a lot of code and making it more
scalable on multi-processor machines.
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Make the dlm_config_info values readable and writeable via configfs
entries.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Add a new dlm_config_info field to enable log_debug output and change
log_debug() to use it.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Add a "ci_" prefix to the fields in the dlm_config_info struct so that we
can use macros to add configfs functions to access them (in a later
patch). No functional changes in this patch, just naming changes.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Some common, non-error messages should use log_debug instead of log_error
so they can be turned off.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
I just noticed this message when testing some other changes I'd made to
lowcomms (to use workqueues) but the problem seems to be in the current
git trees too. I'm amazed no-one has seen it.
BUG: spinlock already unlocked on CPU#1, dlm_recoverd/16868
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
I was a little over-enthusiastic turning schedule() calls int cond_sched() when fixing the DLM for Andrew Morton.
These four should really be calls to schedule() or the dlm can busy-wait.
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Remove the following unused functions:
- lowcomms_send_message()
- lowcomms_max_buffer_size()
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
When the dlm fakes an unlock/cancel reply from a failed node using a stub
message struct, it wasn't setting the flags in the stub message. So, in
the process of receiving the fake message the lkb flags would be updated
and cleared from the zero flags in the message. The problem observed in
tests was the loss of the USER flag which caused the dlm to think a user
lock was a kernel lock and subsequently fail an assertion checking the
validity of the ast/callback field.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
LVB's are not sent as part of new requests, but the code receiving the
request was copying data into the lvb anyway. The space in the message
where it mistakenly thought the lvb lived actually contained the resource
name, so it wound up incorrectly copying this name data into the lvb. Fix
is to just create the lvb, not copy junk into it.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
The send_args() function is used to copy parameters into a message for a
number different message types. Only some of those types are set up
beforehand (in create_message) to include space for sending lvb data.
send_args was wrongly copying the lvb for all message types as long as the
lock had an lvb. This means that the lvb data was being written past the
end of the message into unknown space.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Check if we receive a message from another lockspace member running a
version of the dlm with an incompatible inter-node message protocol.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
A reply to a recovery message will often be received after the relevant
recovery sequence has aborted and the next recovery sequence has begun.
We need to ignore replies to these old messages from the previous
recovery. There's already a way to do this for synchronous recovery
requests using the rc_id number, but not for async.
Each recovery sequence already has a locally unique sequence number
associated with it. This patch adds a field to the rcom (recovery
message) structure where this recovery sequence number can be placed,
rc_seq. When a node sends a reply to a recovery request, it copies the
rc_seq number it received into rc_seq_reply. When the first node receives
the reply to its recovery message, it will check whether rc_seq_reply
matches the current recovery sequence number, ls_recover_seq, and if not
then it ignores the old reply.
An old, inadequate approach to filtering out old replies (checking if the
current stage of recovery has moved back to the start) has been removed
from two spots.
The protocol version number is changed to reflect the different rcom
structures.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
There's a chance the new master of resource hasn't learned it's the new
master before another node sends it a lock during recovery. The node
sending the lock needs to resend if this happens.
- A sends a master lookup for resource R to C
- B sends a master lookup for resource R to C
- C receives A's lookup, assigns A to be master of R and
sends a reply back to A
- C receives B's lookup and sends a reply back to B saying
that A is the master
- B receives lookup reply from C and sends its lock for R to A
- A receives lock from B, doesn't think it's the master of R
and sends an error back to B
- A receives lookup reply from C and becomes master of R
- B gets error back from A and resends its lock back to A
(this resending is what this patch does)
- A receives lock from B, it now sees it's the master of R
and takes the lock
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch fixes a compile warning in lowcomms-tcp.c indicating that
kmem_cache_t is deprecated.
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
* master.kernel.org:/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw: (73 commits)
[DLM] Clean up lowcomms
[GFS2] Change gfs2_fsync() to use write_inode_now()
[GFS2] Fix indent in recovery.c
[GFS2] Don't flush everything on fdatasync
[GFS2] Add a comment about reading the super block
[GFS2] Mount problem with the GFS2 code
[GFS2] Remove gfs2_check_acl()
[DLM] fix format warnings in rcom.c and recoverd.c
[GFS2] lock function parameter
[DLM] don't accept replies to old recovery messages
[DLM] fix size of STATUS_REPLY message
[GFS2] fs/gfs2/log.c:log_bmap() fix printk format warning
[DLM] fix add_requestqueue checking nodes list
[GFS2] Fix recursive locking in gfs2_getattr
[GFS2] Fix recursive locking in gfs2_permission
[GFS2] Reduce number of arguments to meta_io.c:getbuf()
[GFS2] Move gfs2_meta_syncfs() into log.c
[GFS2] Fix journal flush problem
[GFS2] mark_inode_dirty after write to stuffed file
[GFS2] Fix glock ordering on inode creation
...
Replace all uses of kmem_cache_t with struct kmem_cache.
The patch was generated using the following script:
#!/bin/sh
#
# Replace one string by another in all the kernel sources.
#
set -e
for file in `find * -name "*.c" -o -name "*.h"|xargs grep -l $1`; do
quilt add $file
sed -e "1,\$s/$1/$2/g" $file >/tmp/$$
mv /tmp/$$ $file
quilt refresh
done
The script was run like this
sh replace kmem_cache_t "struct kmem_cache"
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This fixes up most of the things pointed out by akpm and Pavel Machek
with comments below indicating why some things have been left:
Andrew Morton wrote:
>
>> +static struct nodeinfo *nodeid2nodeinfo(int nodeid, gfp_t alloc)
>> +{
>> + struct nodeinfo *ni;
>> + int r;
>> + int n;
>> +
>> + down_read(&nodeinfo_lock);
>
> Given that this function can sleep, I wonder if `alloc' is useful.
>
> I see lots of callers passing in a literal "0" for `alloc'. That's in fact
> a secret (GFP_ATOMIC & ~__GFP_HIGH). I doubt if that's what you really
> meant. Particularly as the code could at least have used __GFP_WAIT (aka
> GFP_NOIO) which is much, much more reliable than "0". In fact "0" is the
> least reliable mode possible.
>
> IOW, this is all bollixed up.
When 0 is passed into nodeid2nodeinfo the function does not try to allocate a
new structure at all. it's an indication that the caller only wants the nodeinfo
struct for that nodeid if there actually is one in existance.
I've tidied the function itself so it's more obvious, (and tidier!)
>> +/* Data received from remote end */
>> +static int receive_from_sock(void)
>> +{
>> + int ret = 0;
>> + struct msghdr msg;
>> + struct kvec iov[2];
>> + unsigned len;
>> + int r;
>> + struct sctp_sndrcvinfo *sinfo;
>> + struct cmsghdr *cmsg;
>> + struct nodeinfo *ni;
>> +
>> + /* These two are marginally too big for stack allocation, but this
>> + * function is (currently) only called by dlm_recvd so static should be
>> + * OK.
>> + */
>> + static struct sockaddr_storage msgname;
>> + static char incmsg[CMSG_SPACE(sizeof(struct sctp_sndrcvinfo))];
>
> whoa. This is globally singly-threaded code??
Yes. it is only ever run in the context of dlm_recvd.
>>
>> +static void initiate_association(int nodeid)
>> +{
>> + struct sockaddr_storage rem_addr;
>> + static char outcmsg[CMSG_SPACE(sizeof(struct sctp_sndrcvinfo))];
>
> Another static buffer to worry about. Globally singly-threaded code?
Yes. Only ever called by dlm_sendd.
>> +
>> +/* Send a message */
>> +static int send_to_sock(struct nodeinfo *ni)
>> +{
>> + int ret = 0;
>> + struct writequeue_entry *e;
>> + int len, offset;
>> + struct msghdr outmsg;
>> + static char outcmsg[CMSG_SPACE(sizeof(struct sctp_sndrcvinfo))];
>
> Singly-threaded?
Yep.
>>
>> +static void dealloc_nodeinfo(void)
>> +{
>> + int i;
>> +
>> + for (i=1; i<=max_nodeid; i++) {
>> + struct nodeinfo *ni = nodeid2nodeinfo(i, 0);
>> + if (ni) {
>> + idr_remove(&nodeinfo_idr, i);
>
> Didn't that need locking?
Not. it's only ever called at DLM shutdown after all the other threads
have been stopped.
>>
>> +static int write_list_empty(void)
>> +{
>> + int status;
>> +
>> + spin_lock_bh(&write_nodes_lock);
>> + status = list_empty(&write_nodes);
>> + spin_unlock_bh(&write_nodes_lock);
>> +
>> + return status;
>> +}
>
> This function's return value is meaningless. As soon as the lock gets
> dropped, the return value can get out of sync with reality.
>
> Looking at the caller, this _might_ happen to be OK, but it's a nasty and
> dangerous thing. Really the locking should be moved into the caller.
It's just an optimisation to allow the caller to schedule if there is no work
to do. if something arrives immediately afterwards then it will get picked up
when the process re-awakes (and it will be woken by that arrival).
The 'accepting' atomic has gone completely. as Andrew pointed out it didn't
really achieve much anyway. I suspect it was a plaster over some other
startup or shutdown bug to be honest.
Signed-off-by: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Cc: Andrew Morton <akpm@osdl.org>
Cc: Pavel Machek <pavel@ucw.cz>
This fixes the following gcc warnings generated on
the architectures where uint64_t != unsigned long long (e.g. ppc64).
fs/dlm/rcom.c:154: warning: format '%llx' expects type 'long long unsigned int', but argument 4 has type 'uint64_t'
fs/dlm/rcom.c:154: warning: format '%llx' expects type 'long long unsigned int', but argument 5 has type 'uint64_t'
fs/dlm/recoverd.c:48: warning: format '%llx' expects type 'long long unsigned int', but argument 3 has type 'uint64_t'
fs/dlm/recoverd.c:202: warning: format '%llx' expects type 'long long unsigned int', but argument 3 has type 'uint64_t'
fs/dlm/recoverd.c:210: warning: format '%llx' expects type 'long long unsigned int', but argument 3 has type 'uint64_t'
Signed-off-by: Ryusuke Konishi <ryusuke@osrg.net>
Signed-off-by: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
We often abort a recovery after sending a status request to a remote node.
We want to ignore any potential status reply we get from the remote node.
If we get one of these unwanted replies, we've often moved on to the next
recovery message and incremented the message sequence counter, so the
reply will be ignored due to the seq number. In some cases, we've not
moved on to the next message so the seq number of the reply we want to
ignore is still correct, causing the reply to be accepted. The next
recovery message will then mistake this old reply as a new one.
To fix this, we add the flag RCOM_WAIT to indicate when we can accept a
new reply. We clear this flag if we abort recovery while waiting for a
reply. Before the flag is set again (to allow new replies) we know that
any old replies will be rejected due to their sequence number. We also
initialize the recovery-message sequence number to a random value when a
lockspace is first created. This makes it clear when messages are being
rejected from an old instance of a lockspace that has since been
recreated.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
When the not_ready routine sends a "fake" status reply with blank status
flags, it needs to use the correct size for a normal STATUS_REPLY by
including the size of the would-be config parameters. We also fill in the
non-existant config parameters with an invalid lvblen value so it's easier
to notice if these invalid paratmers are ever being used.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Requests that arrive after recovery has started are saved in the
requestqueue and processed after recovery is done. Some of these requests
are purged during recovery if they are from nodes that have been removed.
We move the purging of the requests (dlm_purge_requestqueue) to later in
the recovery sequence which allows the routine saving requests
(dlm_add_requestqueue) to avoid filtering out requests by nodeid since the
same will be done by the purge. The current code has add_requestqueue
filtering by nodeid but doesn't hold any locks when accessing the list of
current nodes. This also means that we need to call the purge routine
when the lockspace is being shut down since the add routine will not be
rejecting requests itself any more.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
The attached patch fixes the DLM config so that it selects the chosen network
transport. It should fix the bug where DLM can be left selected when NET gets
unselected. This incorporates all the comments received about this patch.
Cc: Adrian Bunk <bunk@stusta.de>
Cc: Andrew Morton <akpm@osdl.org>
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
RH BZ 211622
The ALTMODE flag can be set in the lock master's copy of the lock but
never cleared, so ALTMODE will also be returned in a subsequent conversion
of the lock when it shouldn't be. This results in lock_dlm incorrectly
switching to the alternate lock mode when returning the result to gfs
which then asserts when it sees the wrong lock state. The fix is to
propagate the cleared sbflags value to the master node when the lock is
requested. QA's d_rwrandirectlarge test triggers this bug very quickly.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Red Hat BZ 211914
The previous patch "[DLM] fix aborted recovery during
node removal" was incomplete as discovered with further testing. It set
the bit for the RS_LOCKS barrier but did not then wait for the barrier.
This is often ok, but sometimes it will cause yet another recovery hang.
If it's a new node that also has the lowest nodeid that skips the barrier
wait, then it misses the important step of collecting and reporting the
barrier status from the other nodes (which is the job of the low nodeid in
the barrier wait routine).
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Red Hat BZ 211914
When many nodes are joining a lockspace simultaneously, the dlm gets a
quick sequence of stop/start events, a pair for adding each node.
dlm_controld in user space sends dlm_recoverd in the kernel each stop and
start event. dlm_controld will sometimes send the stop before
dlm_recoverd has had a chance to take up the previously queued start. The
stop aborts the processing of the previous start by setting the
RECOVERY_STOP flag. dlm_recoverd is erroneously clearing this flag and
ignoring the stop/abort if it happens to take up the start after the stop
meant to abort it. The fix is to check the sequence number that's
incremented for each stop/start before clearing the flag.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Red Hat BZ 211914
With the new cluster infrastructure, dlm recovery for a node removal can
be aborted and restarted for a node addition. When this happens, the
restarted recovery isn't aware that it's doing recovery for the earlier
removal as well as the addition. So, it then skips the recovery steps
only required when nodes are removed. This can result in locks not being
purged for failed/removed nodes. The fix is to check for removed nodes
for which recovery has not been completed at the start of a new recovery
sequence.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Red Hat BZ 211914
There's a race between dlm_recoverd (1) enabling locking and (2) clearing
out the requestqueue, and dlm_recvd (1) checking if locking is enabled and
(2) adding a message to the requestqueue. An order of recoverd(1),
recvd(1), recvd(2), recoverd(2) will result in a message being left on the
requestqueue. The fix is to have dlm_recvd check if dlm_recoverd has
enabled locking after taking the mutex for the requestqueue and if it has
processing the message instead of queueing it.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Red Hat BZ 213682
If two nodes leave the lockspace (while unmounting the fs in the case of
gfs) after one has sent a STATUS message to the other, STATUS/STATUS_REPLY
messages will then ping-pong between the nodes when neither of them can
find the lockspace in question any longer. We kill this by not sending
another STATUS message when we get a STATUS_REPLY for an unknown
lockspace.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Red Hat BZ 213684
If a node sends an lkb to the new master (RCOM_LOCK message) during
recovery and recovery is then aborted on both nodes before it gets a
reply, the res_recover_locks_count needs to be reset to 0 so that when the
subsequent recovery comes along and sends the lkb to the new master again
the assertion doesn't trigger that checks that counter is zero.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
The following patch adds a TCP based communications layer
to the DLM which is compile time selectable. The existing SCTP
layer gives the advantage of allowing multihoming, whereas
the TCP layer has been heavily tested in previous versions of
the DLM and is known to be robust and therefore can be used as
a baseline for performance testing.
Signed-off-by: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Now that the lockspace struct is freed when the last sysfs object is released
this patch prevents use of that lockspace by sysfs. We attempt to re-get the
lockspace from the lockspace list and fail the request if it has been removed.
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch fixes the recounting on the lockspace kobject. Previously the lockspace was freed while userspace could have had a
reference to one of its sysfs files, causing an oops in kref_put.
Now the lockspace kfree is moved into the kobject release() function
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
I didn't spot that the msg_iovlen was set to 2 if there
were two elements in the iovec but left at zero if not :(
I think this might be why bob was still seeing trouble.
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
The DLM always passes the iovec length as 1, this is wrong when the circular
buffer wraps round.
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Don't show an empty "Distributed Lock Manager" menu if IP_SCTP=n.
Reported by Dmytro Bagrii in kernel Bugzilla #7268.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
The following patches reduce the size of the VFS inode structure by 28 bytes
on a UP x86. (It would be more on an x86_64 system). This is a 10% reduction
in the inode size on a UP kernel that is configured in a production mode
(i.e., with no spinlock or other debugging functions enabled; if you want to
save memory taken up by in-core inodes, the first thing you should do is
disable the debugging options; they are responsible for a huge amount of bloat
in the VFS inode structure).
This patch:
The filesystem or device-specific pointer in the inode is inside a union,
which is pretty pointless given that all 30+ users of this field have been
using the void pointer. Get rid of the union and rename it to i_private, with
a comment to explain who is allowed to use the void pointer. This is just a
cleanup, but it allows us to reuse the union 'u' for something something where
the union will actually be used.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Fixing the following scenario:
- A request is on the waiters list waiting for a reply from a remote node.
- The request is the first one on the resource, so first_lkid is set.
- The remote node fails causing recovery.
- During recovery the requesting node becomes master.
- The request is now processed locally instead of being a remote operation.
- At this point we need to call confirm_master() on the resource since
we're certain we're now the master node. This will clear first_lkid.
- We weren't calling confirm_master(), so first_lkid was not being cleared
causing subsequent requests on that resource to get stuck.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Use snprintf(buf, PAGE_SIZE, ...) instead of sprintf in sysfs show
methods.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Check if the FORCEFREE flag has been provided from user space. If so, set
the force option to dlm_release_lockspace() so that any remaining locks
will be freed.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
When a new lockspace was being created, the recoverd thread was being
started for it before the lockspace was added to the global list of
lockspaces. The new thread was looking up the lockspace in the global
list and sometimes not finding it due to the race with the original thread
adding it to the list. We need to add the lockspace to the global list
before starting the thread instead of after, and if the new thread can't
find the lockspace for some reason, it should return an error.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
When there are no locks on a resource, the recover_locks() function fails
to clear the NEW_MASTER flag by going directly to out, missing the line
that clears the flag.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
When a status reply is sent for a lockspace that doesn't yet exist, the
message sequence number from the sender was not being copied into the
reply causing the sender to ignore the reply.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
The down-conversion optimization was resulting in the lkb flags being
cleared because the stub message reply had no flags value set. Copy the
current flags into the stub message so they'll be copied back into the lkb
as part of processing the fake reply. Also add an assertion to catch this
error more directly if it exists elsewhere.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Oh, and here's (hopefully) the last of these ua_tmp patches. I think I've
caught all the paths now. Sorry it didn't make the last one.
Signed-off-by: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch fixes bz#203444 where the LKSB was lost during userland conversion
operations
Signed-off-by: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Introduce new function dlm_dump_rsb() to call within assertions instead of
dlm_print_rsb(). The new function dumps info about all locks on the rsb
in addition to rsb details.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Doing the kmap() while holding the spinlock was causing recursive spinlock
problems. It seems the kmap was scheduling, although there was no warning
as I'd expect. Patrick, do we need locking around the kmap?
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
When recoveries are aborted by other recoveries we can get replies to
status or names requests that we've given up on. This can cause problems
if we're making another request and receive an old reply. Add a sequence
number to status/names requests and reject replies that don't match. A
field already exists for the seq number that's used in other message
types.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
To aid debugging, it's useful to be able to see what nodeid the dlm is
waiting on for a message reply.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
When the debug buffer has filled up, break from the loop and return the
correct number of bytes that have been written.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
When we abort one recovery to do another, break out of the ping_members()
routine more quickly, and wake up the dlm_recoverd thread more quickly
instead of waiting for it to time out.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Print the violating name length in the assertion.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch fixes the userland DLM unlock code so that it correctly returns the
address of the userland lock status block in its completion AST.
It fixes bug #201348
Patrick
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
> I think you must have an old version of the base kernel as well?
> i_private no longer exists in struct inode, so you'll have to use
> something else,
I have that patch in my stack but didn't send it; for some reason I
thought it was already changed in your git tree.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
On Wed, Jul 26, 2006 at 10:47:14AM +0100, Steven Whitehouse wrote:
> Hi,
>
> I've applied all the patches you sent, but they don't build:
Argh, sorry about that... when I fixed these a long time ago they somehow
never got included in the quilt patches. I mistakenly assumed the quilt
patches matched the source I had in front of me.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
The loop through all waiting locks in recover_waiters can potentially be
long, so we should schedule explicitly.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
The loop in grant_after_purge is intended to find all rsb's in each hash
bucket that have the LOCKS_PURGED flag set. The loop was quitting the
current bucket after finding just one rsb instead of going until there are
no more.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
If a node becomes the new master of an rsb during recovery, the
LOCKS_PURGED flag needs to be set on it so that any waiting/converting
locks will try to be granted.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Display more information from debugfs, particularly locks waiting for
a master lookup or operations waiting for a remote reply.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
User NOQUEUE lock requests to a remote node that failed with -EAGAIN were
never being removed from a process's list of locks.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
On Thu, Jul 13, 2006 at 10:48:00PM -0700, Andrew Morton wrote:
>...
> Changes since 2.6.18-rc1-mm1:
>...
> git-gfs2.patch
>...
> git trees.
>...
This patch removes the unused EXPORT_SYMBOL_GPL(dlm_lvb_operations).
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This changes the way the dlm handles user locks. The core dlm is now
aware of user locks so they can be dealt with more efficiently. There is
no more dlm_device module which previously managed its own duplicate copy
of every user lock.
Signed-off-by: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Just spotted this one. The lockinfo structs are hashed by lockid but into a
global structure. So that if there are two lockspaces with the same lockid all
hell breaks loose. I'm not exactly sure what will happen but it can't be good!
The attached patch moves the lockinfo_idr into the user_ls structure so that
lockids are localised.
patrick
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
The nodeinfo_lock rwsem needs to be initialized when the module is loaded
instead of when the dlm is first used.
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>
Change names of local_nodeid to dlm_local_nodeid to prevent a
namespace collision. Changed other local variable to match.
Cc: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
In dlm_grant_after_purge() we were holding a hash table read_lock while
calling put_rsb() which potentially removes the rsb from the hash table,
taking the same lock in write. Fix this by flagging rsb's ahead of time
that have been purged. Then iteratively read_lock the hash table, find a
flagged rsb, unlock, process rsb.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Expose the current recovery state in sysfs to help in debugging.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
When a node is removed from a lockspace configuration, close our
connection to it, clearing any remaining messages for it.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Lockspaces created from user space should be forcibly freed without
requiring any further user space interaction.
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Convert a semaphore into a completion in device.c.
Cc: David Teigland <teigland@redhat.com>
Cc: Andrew Morton <akpm@osdl.org>
Signed-off-by: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
We now depend on user selectable options rather than
select them. There is no dependancy on SYSFS since this
selection is independant of the DLM (even though it wouldn't
be sensible to build the DLM without it)
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
In some cases a lockspace isn't attached to the lkb, so that
it needs to be passed directly to the lkb put function.
Signed-off-by: David Teigland <teigland@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>
Patrick Caulfeld