a) in device_write(): add sentinel NUL byte, making sure that lspace.name will
be NUL-terminated
b) in compat_input() be keep it simple about the amounts of data we are copying.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Teigland <teigland@redhat.com>
... those can happen and BUG() from DLM_ASSERT() in allocate_direntry() is
not a good way to handle them.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Teigland <teigland@redhat.com>
We *can* get there from receive_request() and dlm_recover_master_copy()
with namelen too large if incoming request is invalid; BUG() from
DLM_ASSERT() in allocate_rsb() is a bit excessive reaction to that
and in case of dlm_recover_master_copy() we would actually oops before
that while calculating hash of up to 64Kb worth of data - with data
actually being 64 _bytes_ in kmalloc()'ed struct.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Teigland <teigland@redhat.com>
* check that length is large enough to cover the non-variable part of message or
rcom resp. (after checking that it's large enough to cover the header, of
course).
* kill more pointless casts
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Teigland <teigland@redhat.com>
a) don't cast the pointer to dlm_header *, we use it as dlm_message *
anyway.
b) we copy the message into a queue element, then pass the pointer to
copy to dlm_receive_message_saved(); declare it properly to make sure
that we have the right alignment.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Teigland <teigland@redhat.com>
also change name_prefix from char pointer to char array.
Signed-off-by: Denis Cheng <crquan@gmail.com>
Signed-off-by: David Teigland <teigland@redhat.com>
A couple small clean-ups. Remove unnecessary wrapper-functions in
rcom.c, and remove unnecessary casting and an unnecessary ASSERT in
util.c.
Signed-off-by: David Teigland <teigland@redhat.com>
The 32/64 compatibility code in the DLM does not check the validity of
the lock name length passed into it, so it can easily overwrite memory
if the value is rubbish (as early versions of libdlm can cause with
unlock calls, it doesn't zero the field).
This patch restricts the length of the name to the amount of data
actually passed into the call.
Signed-off-by: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
To prevent the master of an rsb from changing rapidly, an unused rsb is kept
on the "toss list" for a period of time to be reused. The toss list was
being cleared completely for each recovery, which is unnecessary. Much of
the benefit of the toss list can be maintained if nodes keep rsb's in their
toss list that they are the master of. These rsb's need to be included
when the resource directory is rebuilt during recovery.
Signed-off-by: David Teigland <teigland@redhat.com>
The invalid lockspace messages are normal and can appear relatively
often. They should be suppressed without debugging enabled.
Signed-off-by: David Teigland <teigland@redhat.com>
The dlm_put_lkb() can free the lkb and its associated ua structure,
so we can't depend on using the ua struct after the put.
Signed-off-by: David Teigland <teigland@redhat.com>
In a rare case we may need to repeat a local resource directory lookup
due to a race with removing the rsb and removing the resdir record.
We'll never need to do more than a single additional lookup, though,
so the infinite loop around the lookup can be removed. In addition
to being unnecessary, the infinite loop is dangerous since some other
unknown condition may appear causing the loop to never break.
Signed-off-by: David Teigland <teigland@redhat.com>
Non-forced unlocks should be rejected if the lock is waiting on the
rsb_lookup list for another lock to establish the master node.
Signed-off-by: David Teigland <teigland@redhat.com>
There was some hit and miss validation of messages that has now been
cleaned up and unified. Before processing a message, the new
validate_message() function checks that the lkb is the appropriate type,
process-copy or master-copy, and that the message is from the correct
nodeid for the the given lkb. Other checks and assertions on the
lkb type and nodeid have been removed. The assertions were particularly
bad since they would panic the machine instead of just ignoring the bad
message.
Although other recent patches have made processing old message unlikely,
it still may be possible for an old message to be processed and caught
by these checks.
Signed-off-by: David Teigland <teigland@redhat.com>
Messages from nodes that are no longer members of the lockspace should be
ignored. When nodes are removed from the lockspace, recovery can
sometimes complete quickly enough that messages arrive from a removed node
after recovery has completed. When processed, these messages would often
cause an error message, and could in some cases change some state, causing
problems.
Signed-off-by: David Teigland <teigland@redhat.com>
When a failed request (EBADR or ENOTBLK) is unlocked/canceled instead of
retried, there may be other lkb's waiting on the rsb_lookup list for it
to complete. A call to confirm_master() is needed to move on to the next
waiting lkb since the current one won't be retried.
Signed-off-by: David Teigland <teigland@redhat.com>
When recovery looks at locks waiting for replies, it fails to consider
locks that have already received a reply for their first remote operation,
but not received a reply for secondary, overlapping unlock/cancel. The
appropriate stub reply needs to be called for these waiters.
Appears when we start doing recovery in the presence of a many overlapping
unlock/cancel ops.
Signed-off-by: David Teigland <teigland@redhat.com>
The lkb_ast_type field indicates whether the lkb is on the astqueue list.
When clearing locks for a process, lkb's were being removed from the astqueue
list without clearing the field. If release_lockspace then happened
immediately afterward, it could try to remove the lkb from the list a second
time.
Appears when process calls libdlm dlm_release_lockspace() which first
closes the ls dev triggering clear_proc_locks, and then removes the ls
(a write to control dev) causing release_lockspace().
Signed-off-by: David Teigland <teigland@redhat.com>
Some errno values differ across platforms. So if we return things like
-EINPROGRESS from one node it can get misinterpreted or rejected on
another one.
This patch fixes up the errno values passed on the wire so that they
match the x86 ones (so as not to break the protocol), and re-instates
the platform-specific ones at the other end.
Many thanks to Fabio for testing this patch.
Initial patch from Patrick.
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>
DLM_RCOM_LOCK_REPLY messages need byte swapping.
Signed-off-by: Fabio M. Di Nitto <fabbione@ubuntu.com>
Signed-off-by: David Teigland <teigland@redhat.com>
gcc does not guarantee that an auto buffer is 64bit aligned.
This change allows sparc64 to work.
Signed-off-by: Fabio M. Di Nitto <fabbione@ubuntu.com>
Signed-off-by: David Teigland <teigland@redhat.com>
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>
