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>
Joel Becker