Commit Graph

24 Commits

Author SHA1 Message Date
Al Viro 4714e63731 ocfs2: fix d_revalidate oopsen on NFS exports
can't blindly check nd->flags in ->d_revalidate()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-03-10 03:45:07 -05:00
Nick Piggin 873feea09e fs: dcache per-inode inode alias locking
dcache_inode_lock can be replaced with per-inode locking. Use existing
inode->i_lock for this. This is slightly non-trivial because we sometimes
need to find the inode from the dentry, which requires d_inode to be
stabilised (either with refcount or d_lock).

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:31 +11:00
Nick Piggin 34286d6662 fs: rcu-walk aware d_revalidate method
Require filesystems be aware of .d_revalidate being called in rcu-walk
mode (nd->flags & LOOKUP_RCU). For now do a simple push down, returning
-ECHILD from all implementations.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:29 +11:00
Nick Piggin dc0474be3e fs: dcache rationalise dget variants
dget_locked was a shortcut to avoid the lazy lru manipulation when we already
held dcache_lock (lru manipulation was relatively cheap at that point).
However, how that the lru lock is an innermost one, we never hold it at any
caller, so the lock cost can now be avoided. We already have well working lazy
dcache LRU, so it should be fine to defer LRU manipulations to scan time.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:24 +11:00
Nick Piggin b5c84bf6f6 fs: dcache remove dcache_lock
dcache_lock no longer protects anything. remove it.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:23 +11:00
Nick Piggin b23fb0a603 fs: scale inode alias list
Add a new lock, dcache_inode_lock, to protect the inode's i_dentry list
from concurrent modification. d_alias is also protected by d_lock.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:22 +11:00
Nick Piggin da5029563a fs: dcache scale d_unhashed
Protect d_unhashed(dentry) condition with d_lock. This means keeping
DCACHE_UNHASHED bit in synch with hash manipulations.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:21 +11:00
Tristan Ye 1989a80a60 Ocfs2: Stop tracking a negative dentry after dentry_iput().
I suddenly hit the problem during 2.6.37-rc1 regression test, which was
introduced by commit '5e98d492406818e6a94c0ba54c61f59d40cefa4a'(Track
negative entries v3), following scenario reproduces the issue easily:

Node A			Node B
================	============
$touch 	testfile
			$ls testfile
$rm -rf testfile
$touch 	testfile
			$ls testfile
			ls: cannot access testfile: No such file or directory

This patch stops tracking the dentry which was negativated by a inode deletion,
so as to force the revaliation in next lookup, in case we'll touch the inode
again in the same node.

It didn't hurt the performance of multiple lookup for none-existed files anyway,
while regresses a bit in the first try after a file deletion.

Signed-off-by: Tristan Ye <tristan.ye@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
2010-11-18 14:10:56 -08:00
Goldwyn Rodrigues 5e98d49240 Track negative entries v3
Track negative dentries by recording the generation number of the parent
directory in d_fsdata. The generation number for the parent directory is
recorded in the inode_info, which increments every time the lock on the
directory is dropped.

If the generation number of the parent directory and the negative dentry
matches, there is no need to perform the revalidate, else a revalidate
is forced. This improves performance in situations where nodes look for
the same non-existent file multiple times.

Thanks Mark for explaining the DLM sequence.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.de>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
2010-09-10 09:18:15 -07:00
Tao Ma a1b08e75df ocfs2: invalidate dentry if its dentry_lock isn't initialized.
In commit a5a0a63092, when
ocfs2_attch_dentry_lock fails, we call an extra iput and reset
dentry->d_fsdata to NULL. This resolve a bug, but it isn't
completed and the dentry is still there. When we want to use
it again, ocfs2_dentry_revalidate doesn't catch it and return
true. That make future ocfs2_dentry_lock panic out.
One bug is http://oss.oracle.com/bugzilla/show_bug.cgi?id=1162.

The resolution is to add a check for dentry->d_fsdata in
revalidate process and return false if dentry->d_fsdata is NULL,
so that a new ocfs2_lookup will be called again.

Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
2009-08-27 18:10:54 -07:00
Jan Kara f7b1aa69be ocfs2: Fix deadlock on umount
In commit ea455f8ab6, we moved the dentry lock
put process into ocfs2_wq. This causes problems during umount because ocfs2_wq
can drop references to inodes while they are being invalidated by
invalidate_inodes() causing all sorts of nasty things (invalidate_inodes()
ending in an infinite loop, "Busy inodes after umount" messages etc.).

We fix the problem by stopping ocfs2_wq from doing any further releasing of
inode references on the superblock being unmounted, wait until it finishes
the current round of releasing and finally cleaning up all the references in
dentry_lock_list from ocfs2_put_super().

The issue was tracked down by Tao Ma <tao.ma@oracle.com>.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
2009-07-21 15:47:55 -07:00
Sunil Mushran a5a0a63092 ocfs2: Add missing iput() during error handling in ocfs2_dentry_attach_lock()
In ocfs2_dentry_attach_lock(), if unable to get the dentry lock, we need to
call iput(inode) because a failure here means no d_instantiate(), which means
the normally matching iput() will not be called during dput(dentry).

This patch fixes the oops that accompanies the following message:
(3996,1):dlm_empty_lockres:2708 ERROR: lockres W00000000000000000a1046b06a4382 still has local locks!
kernel BUG in dlm_empty_lockres at /rpmbuild/smushran/BUILD/ocfs2-1.4.2/fs/ocfs2/dlm/dlmmaster.c:2709!

Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
2009-04-23 14:56:13 -07:00
Al Viro d8fba0ffe5 constify dentry_operations: OCFS2
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-27 14:44:02 -04:00
Jan Kara ea455f8ab6 ocfs2: Push out dropping of dentry lock to ocfs2_wq
Dropping of last reference to dentry lock is a complicated operation involving
dropping of reference to inode. This can get complicated and quota code in
particular needs to obtain some quota locks which leads to potential deadlock.
Thus we defer dropping of inode reference to ocfs2_wq.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-02-02 14:20:16 -08:00
Mark Fasheh 34d024f843 ocfs2: Remove mount/unmount votes
The node maps that are set/unset by these votes are no longer relevant, thus
we can remove the mount and umount votes. Since those are the last two
remaining votes, we can also remove the entire vote infrastructure.

The vote thread has been renamed to the downconvert thread, and the small
amount of functionality related to managing it has been moved into
fs/ocfs2/dlmglue.c. All references to votes have been removed or updated.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
2008-01-25 14:45:34 -08:00
Mark Fasheh bccb9dad89 ocfs2: Remove bug statement in ocfs2_dentry_iput()
The existing bug statement didn't take into account unhashed dentries which
might not have a cluster lock on them. This could happen if a node exporting
the file system via NFS is rebooted, re-exported to nfs clients and then
unmounted. It's fine in this case to not have a dentry cluster lock.

Just remove the bug statement and replace it with an error print, which
does the proper checks. Though we want to know if something has happened
which might have prevented a cluster lock from being created, it's
definitely not necessary to panic the machine for this.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
2007-11-27 16:47:02 -08:00
Mark Fasheh 9f70968af3 ocfs2: Re-order iput in ocfs2_drop_dentry_lock
Do this to avoid a theoretical (I haven't seen this in practice) race where
the downconvert thread might drop the dentry lock, allowing a remote unlink
to proceed before dropping the inode locks. This could bounce access to the
orphan dir between nodes.

There doesn't seem to be a need to do the same in ocfs2_dentry_iput() as
that's never called for the last ref drop from the downconvert thread.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
2007-11-06 15:31:52 -08:00
Robert P. J. Day 3a4fa0a25d Fix misspellings of "system", "controller", "interrupt" and "necessary".
Fix the various misspellings of "system", controller", "interrupt" and
"[un]necessary".

Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
2007-10-19 23:10:43 +02:00
Mark Fasheh 0027dd5bc2 ocfs2: Remove special casing for inode creation in ocfs2_dentry_attach_lock()
We can't use LKM_LOCAL for new dentry locks because an unlink and subsequent
re-create of a name/inode pair may result in the lock still being mastered
somewhere in the cluster.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
2006-09-24 13:50:45 -07:00
Mark Fasheh 1ba9da2ffa ocfs2: manually d_move() during ocfs2_rename()
Make use of FS_RENAME_DOES_D_MOVE to avoid a race condition that can occur
during ->rename() if we d_move() outside of the parent directory cluster
locks, and another node discovers the new name (created during the rename)
and unlinks it. d_move() will unconditionally rehash a dentry - which will
leave stale data in the system.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
2006-09-24 13:50:45 -07:00
Mark Fasheh 80c05846f6 ocfs2: Add dentry tracking API
Replace the dentry vote mechanism with a cluster lock which covers a set
of dentries. This allows us to force d_delete() only on nodes which actually
care about an unlink.

Every node that does a ->lookup() gets a read only lock on the dentry, until
an unlink during which the unlinking node, will request an exclusive lock,
forcing the other nodes who care about that dentry to d_delete() it. The
effect is that we retain a very lightweight ->d_revalidate(), and at the
same time get to make large improvements to the average case performance of
the ocfs2 unlink and rename operations.

This patch adds the higher level API and the dentry manipulation code.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
2006-09-24 13:50:43 -07:00
Mark Fasheh d680efe9d8 ocfs2: Add new cluster lock type
Replace the dentry vote mechanism with a cluster lock which covers a set
of dentries. This allows us to force d_delete() only on nodes which actually
care about an unlink.

Every node that does a ->lookup() gets a read only lock on the dentry, until
an unlink during which the unlinking node, will request an exclusive lock,
forcing the other nodes who care about that dentry to d_delete() it. The
effect is that we retain a very lightweight ->d_revalidate(), and at the
same time get to make large improvements to the average case performance of
the ocfs2 unlink and rename operations.

This patch adds the cluster lock type which OCFS2 can attach to
dentries.  A small number of fs/ocfs2/dcache.c functions are stubbed
out so that this change can compile.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
2006-09-24 13:50:42 -07:00
Mark Fasheh b0697053f9 ocfs2: don't use MLF* in the file system
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
2006-03-24 14:58:28 -08:00
Mark Fasheh ccd979bdbc [PATCH] OCFS2: The Second Oracle Cluster Filesystem
The OCFS2 file system module.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
Signed-off-by: Kurt Hackel <kurt.hackel@oracle.com>
2006-01-03 11:45:47 -08:00