The rwlock is almost always used in write mode, so there's no reason
to not use a spinlock instead.
Signed-off-by: David Teigland <teigland@redhat.com>
The old code would leak iterators and leave reference counts on
rsbs because it was ignoring the "stop" seq callback. The code
followed an example that used the seq operations differently.
This new code is based on actually understanding how the seq
operations work. It also improves things by saving the hash bucket
in the position to avoid cycling through completed buckets in start.
Siged-off-by: Davd Teigland <teigland@redhat.com>
fs/dlm/ast.c: In function 'dlm_astd':
fs/dlm/ast.c:64: warning: 'bastmode' may be used uninitialized in this function
Cleans code up.
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Teigland <teigland@redhat.com>
The new debugfs entry dumps all rsb and lkb structures, and includes
a lot more information than has been available before. This includes
the new timestamps added by a previous patch for debugging callback
issues.
Signed-off-by: David Teigland <teigland@redhat.com>
Record the time the latest blocking callback was queued for
a lock. This will be used for debugging in combination with
lock queue timestamp changes in the previous patch.
Signed-off-by: David Teigland <teigland@redhat.com>
Use ktime instead of jiffies for timestamping lkb's. Also stamp the
time on every lkb whenever it's added to a resource queue, instead of
just stamping locks subject to timeouts. This will allow us to use
timestamps more widely for debugging all locks.
Signed-off-by: David Teigland <teigland@redhat.com>
The lkb bastmode value is set in the context of processing the
lock, and read by the dlm_astd thread. Because it's accessed
in these two separate contexts, the writing/reading ought to
be done under a lock. This is simple to do by setting it and
reading it when the lkb is added to and removed from dlm_astd's
callback list which is properly locked.
Signed-off-by: David Teigland <teigland@redhat.com>
Just before delivering a blocking callback (bast), the dlm_astd
thread checks again that the granted mode of the lkb actually
blocks the mode requested by the bast. The idea behind this was
originally that the granted mode may have changed since the bast
was queued, making the callback now unnecessary. Reasons for
removing this extra check are:
- dlm_astd doesn't lock the rsb before reading the lkb grmode, so
it's not technically safe (this removes the long standing FIXME)
- after running some tests, it doesn't appear the check ever actually
eliminates a bast
- delivering an unnecessary blocking callback isn't a bad thing and
can happen anyway
Signed-off-by: David Teigland <teigland@redhat.com>
This is a one-liner to use cond_resched() rather than schedule()
in the ast delivery loop. It should not be necessary to schedule
every time, so this will save some cpu time while continuing to
allow scheduling when required.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
The pages used in lowcomms are not highmem, so kmap is not necessary.
Cc: Christine Caulfield <ccaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
Use ls_allocation for memory allocations, which a cluster fs sets to
GFP_NOFS. Use GFP_NOFS for allocations when no lockspace struct is
available. Taking dlm locks needs to avoid calling back into the
cluster fs because write-out can require taking dlm locks.
Cc: Christine Caulfield <ccaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
this warning:
fs/dlm/netlink.c: In function ‘dlm_timeout_warn’:
fs/dlm/netlink.c:131: warning: ‘send_skb’ may be used uninitialized in this function
triggers because GCC does not recognize the (correct) error flow
between prepare_data() and send_skb.
Annotate it.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fixes a regression from commit 0f8e0d9a31,
"dlm: allow multiple lockspace creates".
An extraneous 'else' slipped into a code fragment being moved from
release_lockspace() to dlm_release_lockspace(). The result of the
unwanted 'else' is that dlm threads and structures are not stopped
and cleaned up when the final dlm lockspace is removed. Trying to
create a new lockspace again afterward will fail with
"kmem_cache_create: duplicate cache dlm_conn" because the cache
was not previously destroyed.
Signed-off-by: David Teigland <teigland@redhat.com>
sparc32:
fs/dlm/config.c:397: error: expected identifier or '(' before '{' token
fs/dlm/config.c: In function 'drop_node':
fs/dlm/config.c:589: warning: initialization from incompatible pointer type
fs/dlm/config.c:589: warning: initialization from incompatible pointer type
fs/dlm/config.c: In function 'release_node':
fs/dlm/config.c:601: warning: initialization from incompatible pointer type
fs/dlm/config.c:601: warning: initialization from incompatible pointer type
fs/dlm/config.c: In function 'show_node':
fs/dlm/config.c:717: warning: initialization from incompatible pointer type
fs/dlm/config.c:717: warning: initialization from incompatible pointer type
fs/dlm/config.c: In function 'store_node':
fs/dlm/config.c:726: warning: initialization from incompatible pointer type
fs/dlm/config.c:726: warning: initialization from incompatible pointer type
Cc: Christine Caulfield <ccaulfie@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Teigland <teigland@redhat.com>
Compare only the addr and port fields of sockaddr structures.
Fixes a problem with ipv6 where sin6_scope_id does not match.
Signed-off-by: David Teigland <teigland@redhat.com>
If dlm_controld (the userspace daemon that controls the setup and
recovery of the dlm) fails, the kernel should shut down the lockspaces
in the kernel rather than leaving them running. This is detected by
having dlm_controld hold a misc device open while running, and if
the kernel detects a close while the daemon is still needed, it stops
the lockspaces in the kernel.
Knowing that the userspace daemon isn't running also allows the
lockspace create/remove routines to avoid waiting on the daemon
for join/leave operations.
Signed-off-by: David Teigland <teigland@redhat.com>
Add a count for lockspace create and release so that create can
be called multiple times to use the lockspace from different places.
Also add the new flag DLM_LSFL_NEWEXCL to create a lockspace with
the previous behavior of returning -EEXIST if the lockspace already
exists.
Signed-off-by: David Teigland <teigland@redhat.com>
Add a dlm_ prefix to the struct names in config.c. This resolves a
conflict with struct node in particular, when include/linux/node.h
happens to be included.
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Teigland <teigland@redhat.com>
A couple of unlikely error conditions were missing a kfree on the error
exit path.
Reported-by: Juha Leppanen <juha_motorsportcom@luukku.com>
Signed-off-by: David Teigland <teigland@redhat.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/dlm:
dlm: fix uninitialized variable for search_rsb_list callers
dlm: release socket on error
dlm: fix basts for granted CW waiting PR/CW
dlm: check for null in device_write
Use a special error value FILE_LOCK_DEFERRED to mean that a locking
operation returned asynchronously. This is returned by
posix_lock_file() for sleeping locks to mean that the lock has been
queued on the block list, and will be woken up when it might become
available and needs to be retried (either fl_lmops->fl_notify() is
called or fl_wait is woken up).
f_op->lock() to mean either the above, or that the filesystem will
call back with fl_lmops->fl_grant() when the result of the locking
operation is known. The filesystem can do this for sleeping as well
as non-sleeping locks.
This is to make sure, that return values of -EAGAIN and -EINPROGRESS by
filesystems are not mistaken to mean an asynchronous locking.
This also makes error handling in fs/locks.c and lockd/svclock.c slightly
cleaner.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: David Teigland <teigland@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The configfs operations ->make_item() and ->make_group() currently
return a new item/group. A return of NULL signifies an error. Because
of this, -ENOMEM is the only return code bubbled up the stack.
Multiple folks have requested the ability to return specific error codes
when these operations fail. This patch adds that ability by changing the
->make_item/group() ops to return ERR_PTR() values. These errors are
bubbled up appropriately. NULL returns are changed to -ENOMEM for
compatibility.
Also updated are the in-kernel users of configfs.
This is a rework of reverted commit 11c3b79218.
Signed-off-by: Joel Becker <joel.becker@oracle.com>
* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mfasheh/ocfs2:
[PATCH] ocfs2: fix oops in mmap_truncate testing
configfs: call drop_link() to cleanup after create_link() failure
configfs: Allow ->make_item() and ->make_group() to return detailed errors.
configfs: Fix failing mkdir() making racing rmdir() fail
configfs: Fix deadlock with racing rmdir() and rename()
configfs: Make configfs_new_dirent() return error code instead of NULL
configfs: Protect configfs_dirent s_links list mutations
configfs: Introduce configfs_dirent_lock
ocfs2: Don't snprintf() without a format.
ocfs2: Fix CONFIG_OCFS2_DEBUG_FS #ifdefs
ocfs2/net: Silence build warnings on sparc64
ocfs2: Handle error during journal load
ocfs2: Silence an error message in ocfs2_file_aio_read()
ocfs2: use simple_read_from_buffer()
ocfs2: fix printk format warnings with OCFS2_FS_STATS=n
[PATCH 2/2] ocfs2: Instrument fs cluster locks
[PATCH 1/2] ocfs2: Add CONFIG_OCFS2_FS_STATS config option
The configfs operations ->make_item() and ->make_group() currently
return a new item/group. A return of NULL signifies an error. Because
of this, -ENOMEM is the only return code bubbled up the stack.
Multiple folks have requested the ability to return specific error codes
when these operations fail. This patch adds that ability by changing the
->make_item/group() ops to return an int.
Also updated are the in-kernel users of configfs.
Signed-off-by: Joel Becker <joel.becker@oracle.com>
gcc 4.3.0 correctly emits the following warning.
search_rsb_list does not *r_ret if no dlm_rsb is found
and _search_rsb may pass the uninitialized value upstream
on the error path when both calls to search_rsb_list
return non-zero error.
The fix sets *r_ret to NULL on search_rsb_list's not-found path.
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: David Teigland <teigland@redhat.com>
It seems that `sock' allocated by sock_create_kern in
tcp_connect_to_sock() of dlm/fs/lowcomms.c is not released if
dlm_nodeid_to_addr an error.
Acked-by: Christine Caulfield <ccaulfie@redhat.com>
Signed-off-by: Masatake YAMATO <yamato@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
The fix in commit 3650925893 was addressing
the case of a granted PR lock with waiting PR and CW locks. It's a
special case that requires forcing a CW bast. However, that forced CW
bast was incorrectly applying to a second condition where the granted
lock was CW. So, the holder of a CW lock could receive an extraneous CW
bast instead of a PR bast. This fix narrows the original special case to
what was intended.
Signed-off-by: David Teigland <teigland@redhat.com>
If `device_write' method is called via "dlm-control",
file->private_data is NULL. (See ctl_device_open() in
user.c. ) Through proc->flags is read.
Signed-off-by: Masatake YAMATO <yamato@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
The return value on writes to the plock device should be
the number of bytes written. It was returning 0 instead
when an nfs lock callback was involved.
Reported-by: Nathan Straz <nstraz@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
Removed the section mismatch message:
WARNING: fs/dlm/dlm.o(.init.text+0x132): Section mismatch in reference from the function init_module() to the function .exit.text:dlm_netlink_exit()
Since dlm_netlink_exit() is called in the init_dlm() error handling,
the __exit annotation has been removed.
Signed-off-by: Leonardo Potenza <lpotenza@inwind.it>
Signed-off-by: David Teigland <teigland@redhat.com>
The semaphore connections_lock is used as a mutex. Convert it to the mutex
API.
Signed-off-by: Matthias Kaehlcke <matthias@kaehlcke.net>
Cc: Christine Caulfield <ccaulfie@redhat.com>
Cc: David Teigland <teigland@redhat.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Teigland <teigland@redhat.com>
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/dlm:
dlm: linux/{dlm,dlm_device}.h: cleanup for userspace
dlm: common max length definitions
dlm: move plock code from gfs2
dlm: recover nodes that are removed and re-added
dlm: save master info after failed no-queue request
dlm: make dlm_print_rsb() static
dlm: match signedness between dlm_config_info and cluster_set
Add central definitions for max lockspace name length and max resource
name length. The lack of central definitions has resulted in scattered
private definitions which we can now clean up, including an unused one
in dlm_device.h.
Signed-off-by: David Teigland <teigland@redhat.com>
Move the code that handles cluster posix locks from gfs2 into the dlm
so that it can be used by both gfs2 and ocfs2.
Signed-off-by: David Teigland <teigland@redhat.com>
If a node is removed from a lockspace, and then added back before the
dlm is notified of the removal, the dlm will not detect the removal
and won't clear the old state from the node. This is fixed by using a
list of added nodes so the membership recovery can detect when a newly
added node is already in the member list.
Signed-off-by: David Teigland <teigland@redhat.com>
When a NOQUEUE request fails, the rsb res_master field is unnecessarily
reset to -1, instead of leaving the valid master setting in place. We
want to save the looked-up master values while the rsb is on the "toss
list" so that another lookup can be avoided if the rsb is soon reused.
The fix is to simply leave res_master value alone.
Signed-off-by: David Teigland <teigland@redhat.com>
cluster_set is only called from the macro CLUSTER_ATTR which defines read/write
access functions. Make the signedness match to avoid sparse warnings every time
CLUSTER_ATTR is used (lines 149-159) all of the form:
fs/dlm/config.c:149:1: warning: incorrect type in argument 3 (different signedness)
fs/dlm/config.c:149:1: expected unsigned int *info_field
fs/dlm/config.c:149:1: got int extern [toplevel] *<noident>
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David Teigland <teigland@redhat.com>
The recent patch to validate data lengths in rcom_names messages
failed to account for fake messages a node directs to itself before
ever sending it. In this case we need to fill in the message length
in the header for the validation code to use.
Signed-off-by: David Teigland <teigland@redhat.com>
it moves 365 bytes from .text to .init.text, and 30 bytes from .text to
.exit.text, saves memory.
Signed-off-by: Denis Cheng <crquan@gmail.com>
Signed-off-by: David Teigland <teigland@redhat.com>
