As requested by Christoph, this patch cleans up GFS2's internal
read function so that it no longer uses the do_generic_mapping_read
function. This function is obsolete and GFS2 is the last user of it.

As a side effect the internal read code gets smaller and easier
to read and gfs2_readpage is split into two. One function has the locking
and the other function has the rest of the logic.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>

Fix a race condition where multiple glock demote requests are sent to
a node back-to-back. This patch does a check inside handle_callback()
to see whether a demote request is in progress. If true, it sets a flag
to make sure run_queue() will loop again to handle the new request,
instead of erronously setting gl_demote_state to a different state.
Signed-off-by: NS. Wendy Cheng <wcheng@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Now that nfsd has stopped writing to the find_exported_dentry member we an
mark the export_operations const
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Cc: Neil Brown <neilb@suse.de>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: <linux-ext4@vger.kernel.org>
Cc: Dave Kleikamp <shaggy@austin.ibm.com>
Cc: Anton Altaparmakov <aia21@cantab.net>
Cc: David Chinner <dgc@sgi.com>
Cc: Timothy Shimmin <tes@sgi.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Chris Mason <mason@suse.com>
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: "Vladimir V. Saveliev" <vs@namesys.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Convert gfs2 to the new ops.  Uses a similar structure to the generic helpers,
but gfs2 has it's own file handle formats.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Cc: Neil Brown <neilb@suse.de>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The early LFS work that Linux uses favours EFBIG in various places. SuSv3
specifically uses EOVERFLOW for this as noted by Michael (Bug 7253)

[EOVERFLOW]
    The named file is a regular file and the size of the file cannot be
represented correctly in an object of type off_t. We should therefore
transition to the proper error return code
Signed-off-by: NAlan Cox <alan@redhat.com>
Cc: Theodore Tso <tytso@mit.edu>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Slab constructors currently have a flags parameter that is never used.  And
the order of the arguments is opposite to other slab functions.  The object
pointer is placed before the kmem_cache pointer.

Convert

        ctor(void *object, struct kmem_cache *s, unsigned long flags)

to

        ctor(struct kmem_cache *s, void *object)

throughout the kernel

[akpm@linux-foundation.org: coupla fixes]
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

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: NGreg Kroah-Hartman <gregkh@suse.de>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The mapping may be NULL by the time the I/O has completed, so
we now get the superblock by a different route (via the bd and glock)
to avoid this problem.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>
Cc: Wendy Cheng <wcheng@redhat.com>

Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

There is a possible deadlock between two processes on the same node, where one
process is deleting an inode, and another process is looking for allocated but
unused inodes to delete in order to create more space.

process A does an iput() on inode X, and it's i_count drops to 0. This causes
iput_final() to be called, which puts an inode into state I_FREEING at
generic_delete_inode(). There no point between when iput_final() is called, and
when I_FREEING is set where GFS2 could acquire any glocks. Once I_FREEING is
set, no other process on that node can successfully look up that inode until
the delete finishes.

process B locks the the resource group for the same inode in get_local_rgrp(),
which is called by gfs2_inplace_reserve_i()

process A tries to lock the resource group for the inode in
gfs2_dinode_dealloc(), but it's already locked by process B

process B waits in find_inode for the inode to have the I_FREEING state cleared.

Deadlock.

This patch solves the problem by adding an alternative to gfs2_iget(),
gfs2_iget_skip(), that simply skips any inodes that are in the I_FREEING
state.o The alternate test function is just like the original one, except that
it fails if the inode is being freed, and sets a skipped flag. The alternate
set function is just like the original, except that it fails if the skipped
flag is set. Only try_rgrp_unlink() calls gfs2_iget_skip() instead of
gfs2_iget().
Signed-off-by: NBenjamin E. Marzinski <bmarzins@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

* GFS2 has been using i_cache array to store its indirect meta blocks.
Its flush routine doesn't correctly clean up all the entries. The
problem would show while multiple nodes do simultaneous writes to the
same file. Upon glock exclusive lock transfer, if the file is a sparse
file with large file size where the indirect meta blocks span multiple
array entries with "zero" entries in between. The flush routine
prematurely stops the flushing that leaves old (stale) entries around.
This leads to several nasty issues, including data corruption.
* Fix gfs2_get_block_noalloc checking to correctly return EIO upon
unmapped buffer.
Signed-off-by: NWendy Cheng <wcheng@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This patch cleans up the code for writing journaled data into the log.
It also removes the need to allocate a small "tag" structure for each
block written into the log. Instead we just keep count of the outstanding
I/O so that we can be sure that its all been written at the correct time.
Another result of this patch is that a number of ll_rw_block() calls
have become submit_bh() calls, closing some races at the same time.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

The problem boiled down to a race between the gdlm_init_threads()
function initializing thread1 and its setting of blist = 1.
Essentially, "if (current == ls->thread1)" was checked by the thread
before the thread creator set ls->thread1.

Since thread1 is the only thread who is allowed to work on the
blocking queue, and since neither thread thought it was thread1, no one
was working on the queue.  So everything just sat.

This patch reuses the ls->async_lock spin_lock to fix the race,
and it fixes the problem.  I've done more than 2000 iterations of the
loop that was recreating the failure and it seems to work.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

--

Move inode deletion code out of blocking_cb handle_callback route to
avoid racy conditions that end up blocking lock_dlm1 thread. Fix
bugzilla 286821.
Signed-off-by: NWendy Cheng <wcheng@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This patch adds a new flag to the gfs2_holder structure GL_FLOCK.
It is set on holders of glocks representing flocks. This flag is
checked in add_to_queue() and a process is permitted to queue more
than one holder onto a glock if it is set. This solves the issue
of a process not being able to do multiple flocks on the same file.
Through a single descriptor, a process can now promote and demote
flocks. Through multiple descriptors a process can now queue
multiple flocks on the same file. There's still the problem of
a process deadlocking itself (because gfs2 blocking locks are not
interruptible) by queueing incompatible deadlock.
Signed-off-by: NAbhijith Das <adas@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

The following alters gfs2_trans_add_revoke() to take a struct
gfs2_bufdata as an argument. This eliminates the memory allocation which
was previously required by making use of the already existing struct
gfs2_bufdata. It makes some sanity checks to ensure that the
gfs2_bufdata has been removed from all the lists before its recycled as
a revoke structure. This saves one memory allocation and one free per
revoke structure.

Also as a result, and to simplify the locking, since there is no longer
any blocking code in gfs2_trans_add_revoke() we must hold the log lock
whenever this function is called. This reduces the amount of times we
take and unlock the log lock.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

The old revoke structure was allocated using kalloc/kfree but
there is a slab cache for gfs2_bufdata, so we should use that
now that the structures have been converted.

This is part two of the patch series to merge the revoke
and gfs2_bufdata structures.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Both the revoke structure and the bufdata structure are quite similar.
They are basically small tags which are put on lists. In addition to
which the revoke structure is always allocated when there is a bufdata
structure which is (or can be) freed. As such it should be possible to
reduce the number of frees and allocations by using the same structure
for both purposes.

This patch is the first step along that path. It replaces existing uses
of the revoke structure with the bufdata structure.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

The following patch removes the ordered write processing from
databuf_lo_before_commit() and moves it to log.c. This has the effect of
greatly simplyfying databuf_lo_before_commit() and well as potentially
making the ordered write code more efficient.

As a side effect of this, its now possible to remove ordered buffers
from the ordered buffer list at any time, so we now make use of this in
invalidatepage and releasepage to ensure timely release of these
buffers.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

gfs2_pin and gfs2_unpin are only used in lops.c, despite being
defined in meta_io.c, so this patch moves them into lops.c and
makes them static. At the same time, its possible to clean up
the locking in the buf and databuf _lo_add() functions so that
we only need to grab the spinlock once. Also we have to move
lock_buffer() around the _lo_add() functions since we can't
do that in gfs2_pin() any more since we hold the spinlock
for the duration of that function.

As a result, the code shrinks by 12 lines and we do far fewer
operations when adding buffers to the log. It also makes the
code somewhat easier to read & understand.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Journaled data is marked dirty by gfs2_unpin and should not be marked
dirty here.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This collects together the operations required to remove a gfs2_bufdata
from the ail lists. Its only called from two places to start with, but
expect to see more of this function in future.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This patch corrects the lock ordering in unlink to be the same as
that in the rest of GFS2, i.e. parent -> child -> rgrp.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Fix a nasty inode meta data corruption issue by keeping the buffer head in
icache array. This buffer needs to stay in memory until journal flush occurs
Otherwise, gfs2_meta_inode_buffer could do a disk read before the inode hits
disk. It ends up with meta data corruptions. The buffer will be released as
part of the existing journal flush logic.
Signed-off-by: NS. Wendy Cheng <wcheng@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

When a lot of IO, with some distributed mmap IO, is run on a GFS2 filesystem in
a cluster, it will deadlock. The reason is that do_no_page() will repeatedly
call gfs2_sharewrite_nopage(), because each node keeps giving up the glock
too early, and is forced to call unmap_mapping_range(). This bumps the
mapping->truncate_count sequence count, forcing do_no_page() to retry. This
patch institutes a minimum glock hold time a tenth a second.  This insures
that even in heavy contention cases, the node has enough time to get some
useful work done before it gives up the glock.

A second issue is that when gfs2_glock_dq() is called from within a page fault
to demote a lock, and the associated page needs to be written out, it will
try to acqire a lock on it, but it has already been locked at a higher level.
This patch puts makes gfs2_glock_dq() use the work queue as well, to avoid this
issue. This is the same patch as Steve Whitehouse originally proposed to fix
this issue, execpt that gfs2_glock_dq() now grabs a reference to the glock
before it queues up the work on it.
Signed-off-by: NBenjamin E. Marzinski <bmarzins@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

When you try to mount gfs2 with -o garbage, the mount fails and the gfs2
superblock is deallocated and becomes NULL. The vfs comes around later
on and calls gfs2_kill_sb. At this point the hidden gfs2 superblock
pointer (sb->s_fs_info) is NULL and dereferencing it through
gfs2_meta_syncfs causes the panic. (the other function call to
gfs2_delete_debugfs_file() succeeds because this function already checks
for a NULL pointer)
Signed-off-by: NAbhijith Das <adas@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This is a patch to GFS2 to protect sd_log_num_jdata with the
gfs2_log_lock.  Without this patch, there is a timing window
where you can get hit the following assert from function
gfs2_log_flush():

gfs2_assert_withdraw(sdp,
			sdp->sd_log_num_buf + sdp->sd_log_num_jdata ==
			sdp->sd_log_commited_buf +
			sdp->sd_log_commited_databuf);

I've tested it on my roth cluster and it fixes the problem.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

With this patch, gfs2 glockdump through the debugfs filesystem will only
dump glocks for the specified filesystem instead of all glocks. Also, to
aid debugging, the glock number is dumped in hex instead of decimal.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>
Signed-off-by: NS. Wendy Cheng <wcheng@redhat.com>
Signed-off-by: NAbhijith Das <adas@redhat.com>

Current GFS2 setattr call unconditionally invokes do_shrink even the
requested size and actual file size are equal. This has generated large
amount of extra IOs found during NFS benchmark runs. This patch moves
the relevant logic out of shrink code path. Since setattr is a system
call, the time stamps update is still required.
Signed-off-by: NS. Wendy Cheng <wcheng@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

match_token() was returning garbage data instead of a fail value. This data
happened to match a valid option id for an option that required an argument (in
this case, lockproto=%s) For match_token() to correctly fail if the option
doesn't match any of the tokens, the token table must end with a NULL entry.
This patch adds the NULL entry.
Signed-off-by: NBenjamin E. Marzinski <bmarzins@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This was missing from the dir_split_leaf() function although in
most cases its not a problem due to other functions having
already previously called gfs2_trans_add_bh. This makes certain
that it is correct.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>
Cc: Wendy Cheng <wcheng@redhat.com>

This patch fixes some bugs relating to journaled data files by cleaning
up the gfs2_invalidatepage() and gfs2_releasepage() functions. We now
never block during gfs2_releasepage(), instead we always either release
or refuse to release depending on the status of the buffers.

This fixes Red Hat bugzillas #248969 and #252392.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>
Cc: Bob Peterson <rpeterso@redhat.com>

This is the filesystem part of the patches to fix this bz. There are
additional userland patches (gfs2_quota, libgfs2) for the complete
solution. This patch adds a new field qu_ll_next to the gfs2_quota
structure. This field allows us to create linked lists of quotas in the
ondisk quota inode. Instead of scanning through the entire sparse quota
file for valid quotas, we can now simply walk through the user and group
quota linked lists to perform the do_list operation.
Signed-off-by: NAbhijith Das <adas@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Signed-off-by: NDenis Cheng <crquan@gmail.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

This patch forcibly unstuffs (if stuffed) the hidden quota inode at the
first availble opportunity. In any practical scenario the quota inode
won't be stuffed, so this is ok to do. Unstuffing the quota inode allows
us to ignore the case of a stuffed quota inode in gfs2_adjust_quota().
Signed-off-by: NAbhijith Das <adas@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

the original code could work, but I think this code could work better.
Signed-off-by: NDenis Cheng <crquan@gmail.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

sb->s_fs_info is a void pointer, thus the type cast is not needed.
Signed-off-by: NDenis Cheng <crquan@gmail.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>