We're going to want it in the ast functions, so we convert union
ocfs2_dlm_lksb to struct ocfs2_dlm_lksb and let it carry the connection.
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

The stackglue ast and bast functions tried to maintain the fiction that
their arguments were void pointers.  In reality, stack_user.c had to
know that the argument was an ocfs2_lock_res in order to get the status
off of the lksb.  That's ugly.

This changes stackglue to always pass the lksb as the argument to ast
and bast functions.  The caller can always use container_of() to get the
ocfs2_lock_res or user_dlm_lock_res.  The net effect to the caller is
zero.  They still get back the lockres in their ast.  stackglue gets
cleaner, and now can use the lksb itself.
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

We're going to remove the tie between ocfs2_dlmfs and o2dlm.
ocfs2_dlmfs doesn't belong in the fs/ocfs2/dlm directory anymore.  Here
we move it to fs/ocfs2/dlmfs.
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

o2dlm's userspace filesystem is an easy way to use the DLM from
userspace.  It is intentionally simple. For example, it does not allow
for asynchronous behavior or lock conversion.  This is intentional to
keep the interface simple.

Because there is no asynchronous notification, there is no way for a
process holding a lock to know another node needs the lock.  This is the
number one complaint of ocfs2_dlmfs users.  Turns out, we can solve this
very easily.  We add poll() support to ocfs2_dlmfs.  When a BAST is
received, the lock's file descriptor will receive POLLIN.

This is trivial to implement.  Userdlm already has an appropriate
waitqueue, and the lock knows when it is blocked.

We add the "bast" capability to tell userspace this is available.
Signed-off-by: NJoel Becker <joel.becker@oracle.com>
Acked-by: NMark Fasheh <mfasheh@suse.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

Over time, dlmfs has added some features that were not part of the
initial ABI.  Unfortunately, some of these features are not detectable
via standard usage.  For example, Linux's default poll always returns
POLLIN, so there is no way for a caller of poll(2) to know when dlmfs
added poll support.  Instead, we provide this list of new capabilities.

Capabilities is a read-only attribute.  We do it as a module parameter
so we can discover it whether dlmfs is built in, loaded, or even not
loaded (via modinfo).

The ABI features are local to this machine's dlmfs mount.  This is
distinct from the locking protocol, which is concerned with inter-node
interaction.
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

ocfs2 can store extended attribute values as large as a single file.  It
does this using a standard ocfs2 btree for the large value.  However,
the previous code did not handle all error cases cleanly.

There are multiple problems to have.

1) We have trouble allocating space for a new xattr.  This leaves us
   with an empty xattr.
2) We overwrote an existing local xattr with a value root, and now we
   have an error allocating the storage.  This leaves us an empty xattr.
   where there used to be a value.  The value is lost.
3) We have trouble truncating a reused value.  This leaves us with the
   original entry pointing to the truncated original value.  The value
   is lost.
4) We have trouble extending the storage on a reused value.  This leaves
   us with the original value safely in place, but with more storage
   allocated when needed.

This doesn't consider storing local xattrs (values that don't require a
btree).  Those only fail when the journal fails.

Case (1) is easy.  We just remove the xattr we added.  We leak the
storage because we can't safely remove it, but otherwise everything is
happy.  We'll print a warning about the leak.

Case (4) is easy.  We still have the original value in place.  We can
just leave the extra storage attached to this xattr.  We return the
error, but the old value is untouched.  We print a warning about the
storage.

Case (2) and (3) are hard because we've lost the original values.  In
the old code, we ended up with values that could be partially read.
That's not good.  Instead, we just wipe the xattr entry and leak the
storage.  It stinks that the original value is lost, but now there isn't
a partial value to be read.  We'll print a big fat warning.
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

ocfs2_xattr_ibody_set() is the only remaining user of
ocfs2_xattr_set_entry().  ocfs2_xattr_set_entry() actually does two
things: it calls ocfs2_xa_set(), and it initializes the inline xattrs.
Initializing the inline space really belongs in its own call.

We lift the initialization to ocfs2_xattr_ibody_init(), called from
ocfs2_xattr_ibody_set() only when necessary.  Now
ocfs2_xattr_ibody_set() can call ocfs2_xa_set() directly.
ocfs2_xattr_set_entry() goes away.

Another nice fact is that ocfs2_init_dinode_xa_loc() can trust
i_xattr_inline_size.
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

ocfs2_xattr_block_set() calls into ocfs2_xattr_set_entry() with just the
HAS_XATTR flag.  Most of the machinery of ocfs2_xattr_set_entry() is
skipped.  All that really happens other than the call to ocfs2_xa_set()
is making sure the HAS_XATTR flag is set on the inode.

But HAS_XATTR should be set when we also set di->i_xattr_loc.  And
that's done in ocfs2_create_xattr_block().  So let's move it there, and
then ocfs2_xattr_block_set() can just call ocfs2_xa_set().

While we're there, ocfs2_create_xattr_block() can take the set_ctxt for
a smaller argument list.  It also learns to set HAS_XATTR_FL, because it
knows for sure.  ocfs2_create_empty_xatttr_block() in the reflink path
fakes a set_ctxt to call ocfs2_create_xattr_block().
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

ocfs2_xattr_set_in_bucket() doesn't need to do its own hacky space
checking.  Let's let ocfs2_xa_prepare_entry() (via ocfs2_xa_set()) do
the more accurate work.  Whenever it doesn't have space,
ocfs2_xattr_set_in_bucket() can try to get more space.
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

ocfs2_xa_set() wraps the ocfs2_xa_prepare_entry()/ocfs2_xa_store_value()
logic.  Both callers can now use the same routine.  ocfs2_xa_remove()
moves directly into ocfs2_xa_set().
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

ocfs2_xa_prepare_entry() gets all the logic to add, remove, or modify
external value trees.  Now, when it exits, the entry is ready to receive
a value of any size.

ocfs2_xa_remove() is added to handle the complete removal of an entry.
It truncates the external value tree before calling
ocfs2_xa_remove_entry().

ocfs2_xa_store_inline_value() becomes ocfs2_xa_store_value().  It can
store any value.

ocfs2_xattr_set_entry() loses all the allocation logic and just uses
these functions.  ocfs2_xattr_set_value_outside() disappears.

ocfs2_xattr_set_in_bucket() uses these functions and makes
ocfs2_xattr_set_entry_in_bucket() obsolete.  That goes away, as does
ocfs2_xattr_bucket_set_value_outside() and
ocfs2_xattr_bucket_value_truncate().
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

We're going to want to make sure our buffers get accessed and dirtied
correctly.  So have the xa_loc do the work.  This includes storing the
inode on ocfs2_xa_loc.
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

We use the ocfs2_xattr_value_buf structure to manage external values.
It lets the value tree code do its work regardless of the containing
storage.  ocfs2_xa_fill_value_buf() initializes a value buf from an
ocfs2_xa_loc entry.
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

Previously the xattr code would send in a fake value, containing a tree
root, to the function that installed name+value pairs.  Instead, we pass
the real value to ocfs2_xa_set_inline_value(), and it notices that the
value cannot fit.  Thus, it installs a tree root.
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

We create two new functions on ocfs2_xa_loc, ocfs2_xa_prepare_entry()
and ocfs2_xa_store_inline_value().

ocfs2_xa_prepare_entry() makes sure that the xl_entry field of
ocfs2_xa_loc is ready to receive an xattr.  The entry will point to an
appropriately sized name+value region in storage.  If an existing entry
can be reused, it will be.  If no entry already exists, it will be
allocated.  If there isn't space to allocate it, -ENOSPC will be
returned.

ocfs2_xa_store_inline_value() stores the data that goes into the 'value'
part of the name+value pair.  For values that don't fit directly, this
stores the value tree root.

A number of operations are added to ocfs2_xa_loc_operations to support
these functions.  This reflects the disparate behaviors of xattr blocks
and buckets.

With these functions, the overlapping ocfs2_xattr_set_entry_local() and
ocfs2_xattr_set_entry_normal() can be replaced with a single call
scheme.
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

An ocfs2 xattr entry stores the text name and value as a pair in the
storage area.  Obviously names and values can be variable-sized.  If a
value is too large for the entry storage, a tree root is stored instead.
The name+value pair is also padded.

Because of this, there are a million places in the code that do:

	if (needs_external_tree(value_size)
		namevalue_size = pad(name_size) + tree_root_size;
	else
		namevalue_size = pad(name_size) + pad(value_size);

Let's create some convenience functions to make the code more readable.
There are three forms.  The first takes the raw sizes.  The second takes
an ocfs2_xattr_info structure.  The third takes an existing
ocfs2_xattr_entry.
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

Rather than calculating strlen all over the place, let's store the
name length directly on ocfs2_xattr_info.
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

struct ocfs2_xattr_info is a useful structure describing an xattr
you'd like to set.  Let's put prefixes on the member fields so it's
easier to read and use.
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

Add ocfs2_xa_remove_entry(), which will remove an xattr entry from its
storage via the ocfs2_xa_loc descriptor.
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

The ocfs2 extended attribute (xattr) code is very flexible.  It can
store xattrs in the inode itself, in an external block, or in a tree of
data structures.  This allows the number of xattrs to be bounded by the
filesystem size.

However, the code that manages each possible storage location is
different.  Maintaining the ocfs2 xattr code requires changing each hunk
separately.

This patch is the start of a series introducing the ocfs2_xa_loc
structure.  This structure wraps the on-disk details of an xattr
entry.  The goal is that the generic xattr routines can use
ocfs2_xa_loc without knowing the underlying storage location.

This first pass merely implements the basic structure, initializing it,
and wiping the name+value pair of the entry.
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

Add current->comm to the standard mlog() output to help with debugging.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

When ocfs2 has to do CoW for refcounted extents, we disable direct I/O
and go through the buffered I/O path.  This makes the combined check
easier to read.
Signed-off-by: NWengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

This patch add extent block (metadata) stealing mechanism for
extent allocation. This mechanism is same as the inode stealing.
if no room in slot specific extent_alloc, we will try to
allocate extent block from the next slot.
Signed-off-by: NTiger Yang <tiger.yang@oracle.com>
Acked-by: NTao Ma <tao.ma@oracle.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

Connect and disconnect messages are more than informational as they are required
during root cause analysis for failures. This patch changes them from KERN_INFO
to KERN_NOTICE.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Acked-by: NMark Faseh <mfasheh@suse.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

The debug call printing the name of the lock resource was chopping
off the last character. This patch fixes the problem.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Acked-by: NMark Fasheh <mfasheh@suse.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

This reverts commit 70362511 ("tty: fix race in tty_fasync") and
commit b04da8bf ("fnctl: f_modown should call write_lock_irqsave/
restore") that tried to fix up some of the fallout but was incomplete.

It turns out that we really cannot hold 'tty->ctrl_lock' over calling
__f_setown, because not only did that cause problems with interrupt
disables (which the second commit fixed), it also causes a potential
ABBA deadlock due to lock ordering.

Thanks to Tetsuo Handa for following up on the issue, and running
lockdep to show the problem.  It goes roughly like this:

 - f_getown gets filp->f_owner.lock for reading without interrupts
   disabled, so an interrupt that happens while that lock is held can
   cause a lockdep chain from f_owner.lock -> sighand->siglock.

 - at the same time, the tty->ctrl_lock -> f_owner.lock chain that
   commit 70362511 introduced, together with the pre-existing
   sighand->siglock -> tty->ctrl_lock chain means that we have a lock
   dependency the other way too.

So instead of extending tty->ctrl_lock over the whole __f_setown() call,
we now just take a reference to the 'pid' structure while holding the
lock, and then release it after having done the __f_setown.  That still
guarantees that 'struct pid' won't go away from under us, which is all
we really ever needed.
Reported-and-tested-by: NTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
Acked-by: NAmérico Wang <xiyou.wangcong@gmail.com>
Cc: stable@kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Hooks: Just Say No.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

ima_path_check actually deals with files!  call it ima_file_check instead.
Signed-off-by: NEric Paris <eparis@redhat.com>
Acked-by: NMimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

The "Untangling ima mess, part 2 with counters" patch messed
up the counters.  Based on conversations with Al Viro, this patch
streamlines ima_path_check() by removing the counter maintaince.
The counters are now updated independently, from measuring the file,
in __dentry_open() and alloc_file() by calling ima_counts_get().
ima_path_check() is called from nfsd and do_filp_open().
It also did not measure all files that should have been measured.
Reason: ima_path_check() got bogus value passed as mask.
[AV: mea culpa]
[AV: add missing nfsd bits]
Signed-off-by: NMimi Zohar <zohar@us.ibm.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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

Thanks Thomas and Christoph for testing and review.
I removed 'smp_wmb()' before up_write from the previous patch,
since up_write() should have necessary ordering constraints.
(I.e. the change of s_frozen is visible to others after up_write)
I'm quite sure the change is harmless but if you are uncomfortable
with Tested-by/Reviewed-by on the modified patch, please remove them.

If MS_RDONLY, freeze_bdev should just up_write(s_umount) instead of
deactivate_locked_super().
Also, keep sb->s_frozen consistent so that remount can check the frozen state.

Otherwise a crash reported here can happen:
http://lkml.org/lkml/2010/1/16/37
http://lkml.org/lkml/2010/1/28/53

This patch should be applied for 2.6.32 stable series, too.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Tested-by: NThomas Backlund <tmb@mandriva.org>
Signed-off-by: NJun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: stable@kernel.org
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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

The wrong member was compared in the continguousness check.
Acked-by: NTao Ma <tao.ma@oracle.com>
Signed-off-by: NRoel Kluin <roel.kluin@gmail.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

This version of the i_size fix for fallocate makes sure we only update
the i_size when the current fallocate is really operating outside of
i_size.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

When running the following fio job

[torrent]
filename=torrent-test
rw=randwrite
size=4g
filesize=4g
bs=4k
ioengine=sync

you would see long stalls where no work was being done.  That is because we were
doing all this extra work to read in the file extent outside of the transaction,
however in the random io case this ends up hurting us because the file extents
are not there to begin with.  So axe this logic, since we end up reading in the
file extent when we go to update it anyway.  This took the fio job from 11 mb/s
with several ~10 second stalls to 24 mb/s to a couple of 1-2 second stalls.
Signed-off-by: NJosef Bacik <josef@redhat.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>

When dropping a empty tree, walk_down_tree() skips checking
extent information for the tree root. This will triggers a
BUG_ON in walk_up_proc().
Signed-off-by: NYan Zheng <zheng.yan@oracle.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>

Mounting a bad filesystem caused a BUG_ON(). The following is steps to
reproduce it.
 # mkfs.btrfs /dev/sda2
 # mount /dev/sda2 /mnt
 # mkfs.btrfs /dev/sda1 /dev/sda2
 (the program says that /dev/sda2 was mounted, and then exits. )
 # umount /mnt
 # mount /dev/sda1 /mnt

At the third step, mkfs.btrfs exited in the way of make filesystem. So the
initialization of the filesystem didn't finish. So the filesystem was bad, and
it caused BUG_ON() when mounting it. But BUG_ON() should be called by the wrong
code, not user's operation, so I think it is a bug of btrfs.

This patch fixes it.
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>

It appears the error return should be negative
Signed-off-by: NRoel Kluin <roel.kluin@gmail.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>

Increase extent buffer's reference count while holding the lock.
Otherwise it can race with try_release_extent_buffer.
Signed-off-by: NYan Zheng <zheng.yan@oracle.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>

During recovery, the dlm frees the locks for the dead node. If it finds a
lock in a resource for the dead node, it expects that node to also have a
ref in that lock resource. If not, it BUGs.

ossbz#1175 was filed with the above BUG. Now, while it is correct that we
should be expecting the ref, I see no reason why we have to BUG. After all,
we are freeing up the lock and clearing the ref.

This patch replaces the BUG_ON with a printk(). Hopefully, that will give
us more clues next time this happens.

http://oss.oracle.com/bugzilla/show_bug.cgi?id=1175Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Acked-by: NMark Fasheh <mfasheh@suse.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>