We can run the tree logging recovery or the orphan cleanup on mount, so we'll
end up looking up a random fs tree in the meantime.  So we need to clean this up
so we don't leave extent buffers hanging around on the cache.  With this patch
we no longer leak extent buffers on failure to mount.  Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

This is the same as the fix from commit

Btrfs: fix bad extent logging

but for O_DIRECT.  I missed this when I fixed the problem originally, we were
still using the em for the orig_start and orig_block_len, which would be the
merged extent.  We need to use the actual extent from the on disk file extent
item, which we have to lookup to make sure it's ok to nocow anyway so just pass
in some pointers to hold this info.  Thanks,

Cc: stable@vger.kernel.org
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

We kept leaking extent buffers when mounting a broken file system and it turns
out it's because not everybody uses read_tree_block properly.  You need to check
and make sure the extent_buffer is uptodate before you use it.  This patch fixes
everybody who calls read_tree_block directly to make sure they check that it is
uptodate and free it and return an error if it is not.  With this we no longer
leak EB's when things go horribly wrong.  Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

If we fail to load block groups halfway through we can leave extent_state's on
the excluded tree.  This is because we just lookup the supers and add them to
the excluded tree regardless of which block group we are looking at currently.
This is a problem because we remove the excluded extents for the range of the
block group only, so if we don't ever load a block group for one of the excluded
extents we won't ever free it.  This fixes the problem by only adding excluded
extents if it falls in the block group range we care about.  With this patch
we're no longer leaking space when we fail to read all of the block groups.
Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

With a users corrupted fs I was getting weird behavior and panics and it turns
out it was because one of his tree blocks had a bogus header level.  So add this
to the sanity checks in the endio handler for tree blocks.  Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

This work is done by btrfs_free_path() anyway so there's no need for this
duplicate work.  Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

A user sent me a btrfs-image that was panicing because of some corruption.  This
is because we pass in a bogus value to btrfs_num_copies, and it panics.  Instead
just return 1.  We only call btrfs_num_copies to see if there are other copies
to try and read for things, so if we just return 1 it will make the callers exit
out with an appropriate error value.  Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

Martin Steigerwald reported a BUG_ON() where we were given a bogus bytenr to
map.  Turns out he is using > PAGESIZE leafsizes.  The readahead stuff is called
every time we do a completion, but we may not have finished reading in all the
pages, so the bytenr we read off the node could be completely bogus.  Fix this
by only calling the readahead hook once all pages have been read in.  Thanks,
Reported-by: Martin Steigerwald <Martin@lichtvoll.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

Martin Steigerwald reported a BUG_ON() in btrfs_map_block where we didn't find
a chunk for a particular block we were trying to map.  This happened because the
block was bogus.  We shouldn't be BUG_ON()'ing in this case, just print a
message and return an error.  This came from reada_add_block and it appears to
deal with an error fine so we should be good there.  Thanks,
Reported-by: Martin Steigerwald <Martin@lichtvoll.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

We need to tag metadata io with REQ_META to avoid priority inversion when using
io throttling cqroups.  Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

So I noticed there is an infinite loop in the slow caching code.  If we return 1
when we hit the end of the tree, so we could end up caching the last block group
the slow way and suddenly we're looping forever because we just keep
re-searching and trying again.  Fix this by only doing btrfs_next_leaf() if we
don't need_resched().  Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

The locking order for stuff is

__sb_start_write
ordered_mutex

but with sync() we don't do __sb_start_write for some strange reason, which
means that our iput in wait_ordered_extents could start a transaction which does
the __sb_start_write while we're holding the ordered_mutex.  Fix this by using
delayed iput in sync.  Thanks,
Reported-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

Since all the quota configurations are loaded in memory, and we can
have ioctl checks before operating in the disk. It is safe to do such
things because qgroup_ioctl_lock is held outside.

Without these extra checks firstly, it should be ok to do user change
for quota operations. For example:

if we want to add an existed qgroup, we will do:
	->add_qgroup_item()
		->add_qgroup_rb()

add_qgroup_item() will return -EEXIST to us, however, qgroups are all
in memory, why not check them in memory firstly.
Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

ulist_add() may return -ENOMEM, fix missing check about
return value.
Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

For created snapshots, the full root_item is copied from the source
root and afterwards selectively modified. The current code forgets
to clear the field received_uuid. The only problem is that it is
confusing when you look at it with 'btrfs subv list', since for
writable snapshots, the contents of the snapshot can be completely
unrelated to the previously received snapshot.
The receiver ignores such snapshots anyway because he also checks
the field stransid in the root_item and that value used to be reset
to zero for all created snapshots.

This commit changes two things:
- clear the received_uuid field for new writable snapshots.
- don't clear the send/receive related information like the stransid
  for read-only snapshots (which makes them useable as a parent for
  the automatic selection of parents in the receive code).
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

Dave reported a BUG_ON() that happened in end_page_writeback() after an abort.
This happened because we unconditionally call end_page_writeback() in the endio
case, which is right.  However when we abort the transaction we will call
end_page_writeback() on any writeback pages we find, which is wrong.  We need to
lock the page and wait on page writeback to complete if it is.  There is nothing
unsafe about this since we are discarding the transaction anyway.  Thanks,
Reported-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

We need such a sanity check for wrong start when we defrag a file, otherwise,
even with a wrong start that's larger than file size, we can end up changing
not only inode's force compress flag but also FS's incompat flags.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

This fixes the following errors:

  fs/btrfs/reada.c: In function ‘btrfs_reada_wait’:
  fs/btrfs/reada.c:958:42: error: invalid operands to binary < (have ‘atomic_t’ and ‘int’)
  fs/btrfs/reada.c:961:41: error: invalid operands to binary < (have ‘atomic_t’ and ‘int’)
Signed-off-by: Vincent Stehlé <vincent.stehle@laposte.net>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: linux-btrfs@vger.kernel.org
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

Argument 'trans' became unnecessary from setup_inline_extent_backref()
that called btrfs_extend_item().
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

Argument 'trans' is not used in btrfs_extend_item().
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

If argument 'trans' is unnecessary in the function where
fixup_low_keys() is called, 'trans' is deleted.
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

Argument 'trans' is not used in fixup_low_keys(). So, remove it.
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

Step to reproduce:
	mkfs.btrfs <disk>
	mount <disk> <mnt>
	dd if=/dev/zero of=/<mnt>/data bs=1M count=10
	sync
	btrfs quota enable <mnt>
	btrfs qgroup create 0/5 <mnt>
	btrfs qgroup limit 5M 0/5 <mnt>
	rm -f /<mnt>/data
	sync
	btrfs qgroup show <mnt>
	dd if=/dev/zero of=data bs=1M count=1

>From the perspective of users, qgroup's referenced or exclusive
is negative,but user can not continue to write data! a workaround
way is to cast u64 to s64 when doing qgroup reservation.
Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Reviewed-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

If out of memory happens, we should return -ENOMEM directly to the caller
rather than continue the work.
Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

In the comment describing the sync_writers field of the btrfs_inode
struct, "fsyncing" was misspelled "fsycing."
Signed-off-by: Nathaniel Yazdani <n1ght.4nd.d4y@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

When tree_mod_log_rewind decides to make a copy of the current tree buffer
for its modifications, it subsequently freed the buffer before unlocking it.
Obviously, those operations are required in reverse order.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

The tree mod log functions were accessing root->node->... directly, without
use of btrfs_root_node() or explicit rcu locking. This could lead to an
extent buffer reference being leaked and another reference being freed too
early when preemtion was enabled.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

Commit d9abbf1c changed tree mod log locking around ROOT_REPLACE operations.
When a tree root is split, however, we were logging removal of all elements
from the root node before logging removal of half of the elements for the
split operation. This leads to a BUG_ON when rewinding.

This commit removes the erroneous logging of removal of all elements.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

The following case will make the incompat/compat flag of the super block
be recovered.
 Task1					|Task2
 flags = btrfs_super_incompat_flags();	|
					|flags = btrfs_super_incompat_flags();
 flags |= new_flag1;			|
					|flags |= new_flag2;
 btrfs_set_super_incompat_flags(flags);	|
					|btrfs_set_super_incompat_flags(flags);
the new_flag1 is recovered.

In order to avoid this problem, we introduce a lock named super_lock into
the btrfs_fs_info structure. If we want to update incompat/compat flags
of the super block, we must hold it.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

The new mount option is set after parsing the remount arguments,
so it is wrong that checking the autodefrag is close or not at
btrfs_remount_prepare(). Fix it.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

Walking backref tree and btrfs quota rely on ulist very much.
This patch tries to use rb_tree to speed up search time.

The original code always checks whether an element
exists before adding a new element, however it costs O(n).

I try to add a rb_tree in the ulist,this is only used to speed up
search. I also do some measurements with quota enabled.

fsstress -p 4 -n 10000

Without this path:
real    0m51.058s       2m4.745s        1m28.222s       1m5.137s
user    0m0.035s        0m0.041s        0m0.105s        0m0.100s
sys     0m12.009s       0m11.246s       0m10.901s       0m10.999s       0m11.287s

With this path:
real    0m55.295s       0m50.960s       1m2.214s        0m48.273s
user    0m0.053s        0m0.095s        0m0.135s        0m0.107s
sys     0m7.766s        0m6.013s        0m6.319s        0m6.030s        0m6.532s

After applying the patch,the execute time is down by ~42%.(11.287s->6.532s)
Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Reviewed-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

Two new flags are added to allow omitting the stream header and the
end command for btrfs send streams. This is used in cases where you
send multiple snapshots back-to-back in one stream.

This used to be encoded like this (with 2 snapshots in this example):
<stream header> + <sequence of commands> + <end cmd> +
<stream header> + <sequence of commands> + <end cmd> + EOF

The new format (if the two new flags are used) is this one:
<stream header> + <sequence of commands> +
                  <sequence of commands> + <end cmd>

Note that the currently existing receivers treat <end cmd> only as
an indication that a new <stream header> is following. This means,
you can just skip the sequence <end cmd> <stream header> without
loosing compatibility. As long as an EOF is following, the currently
existing receivers handle the new format (if the two new flags are
used) exactly as the old one.

So what is the benefit of this change? The goal is to be able to use
a single stream (one TCP connection) to multiplex a request/response
handshake plus Btrfs send streams, all in the same stream. In this
case you cannot evaluate an EOF condition as an end of the Btrfs send
stream. You need something else, and the <end cmd> is just perfect
for this purpose.

The summary is:
The format change is driven by the need to send several Btrfs send
streams over a single TCP connections, with the ability for a repeated
request/response handshake in the middle. And this format change does
not break any existing tool, it is completely compatible.

You could compare the old behaviour of the Btrfs send stream to the
one of ftp where you need a seperate request/response channel and
newly opened data transfer channels for each file, while the new
behaviour is more like http using a single stream for everything.
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

__merge_refs() always return 0, it is unnecessary
for the caller to check the return value.
Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

The only error return value of __add_prelim_ref() is -ENOMEM,
just return errors rather than trigger BUG_ON().
Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

Steps to reproduce:
	mkfs.btrfs <disk>
	mount <disk> <mnt>
	btrfs quota enable <mnt>
	btrfs sub create <mnt>/subv
	btrfs qgroup limit 10K <mnt>/subv
	btrfs quota disable <mnt>/subv

It is wrong for qgroup to reserve when disabling quota,
so just use tree_root to avoid edquot when disabling quota.
Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

Step to reproduce:
	mkfs.btrfs <disk>
	mount <disk> <mnt>
	btrfs quota enable <mnt>
	btrfs qgroup limit 0/1 <mnt>
	dmesg

If the relative qgroup dosen't exist, flag 'BTRFS_QGROUP_STATUS_
FLAG_INCONSISTENT' will be set, and print the noise message.
This is wrong, we can just move find_qgroup_rb() before
update_qgroup_limit_item().this dosen't change the logic of the
function. But it can avoid unnecessary noise message and wrong set of flag.
Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

The original code forgot to check 'inherit', we should
gurantee that all the qgroups in the struct 'inherit' exist.
Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Reviewed-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

Step to reproduce:
		mkfs.btrfs <disk>
		mount <disk> <mnt>
		btrfs quota enable <mnt>
		btrfs qgroup assign 0/1 1/1 <mnt>
		umount <mnt>
		btrfs-debug-tree <disk> | grep QGROUP
If we want to add a qgroup relation, we should gurantee that
'src' and 'dst' exist, otherwise, such qgroup relation should
not be allowed to create.
Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Reviewed-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>