Btrfs: update to use fs_state bit

Now that we use bit operation to check fs_state, update
btrfs_free_fs_root()'s checker, otherwise we get back to
memory leak case.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Btrfs: handle a bogus chunk tree nicely

If you restore a btrfs-image file system and try to mount that file system we'll
panic.  That's because btrfs-image restores and just makes one big chunk to
envelope the whole disk, since they are really only meant to be messed with by
our btrfs-progs.  So fix up btrfs_rmap_block and the callers of it for mount so
that we no longer panic but instead just return an error and fail to mount.
Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Btrfs: fix missing qgroup reservation before fallocating

Steps to reproduce:
	mkfs.btrfs <disk>
	mount <disk> <mnt>
	btrfs quota enable <mnt>
	btrfs sub create <mnt>/subv
	btrfs qgroup limit 10M <mnt>/subv
	fallocate --length 20M <mnt>/subv/data

For the above example, fallocating will return successfully which
is not expected, we try to fix it by doing qgroup reservation before
fallocating.

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>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Btrfs: fix locking on ROOT_REPLACE operations in tree mod log

To resolve backrefs, ROOT_REPLACE operations in the tree mod log are
required to be tied to at least one KEY_REMOVE_WHILE_FREEING operation.
Therefore, those operations must be enclosed by tree_mod_log_write_lock()
and tree_mod_log_write_unlock() calls.

Those calls are private to the tree_mod_log_* functions, which means that
removal of the elements of an old root node must be logged from
tree_mod_log_insert_root. This partly reverts and corrects commit ba1bfbd5
(Btrfs: fix a tree mod logging issue for root replacement operations).

This fixes the brand-new version of xfstest 276 as of commit cfe73f71.

Cc: stable@vger.kernel.org
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Btrfs: fix memory leak in btrfs_create_tree()

We should free leaf and root before returning from the error
handling code.

Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Btrfs: fix race between mmap writes and compression

Btrfs uses page_mkwrite to ensure stable pages during
crc calculations and mmap workloads.  We call clear_page_dirty_for_io
before we do any crcs, and this forces any application with the file
mapped to wait for the crc to finish before it is allowed to change
the file.

With compression on, the clear_page_dirty_for_io step is happening after
we've compressed the pages.  This means the applications might be
changing the pages while we are compressing them, and some of those
modifications might not hit the disk.

This commit adds the clear_page_dirty_for_io before compression starts
and makes sure to redirty the page if we have to fallback to
uncompressed IO as well.

Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Reported-by: Alexandre Oliva <oliva@gnu.org>
cc: stable@vger.kernel.org
Btrfs: fix EIO from btrfs send in is_extent_unchanged for punched holes

When you take a snapshot, punch a hole where there has been data, then take
another snapshot and try to send an incremental stream, btrfs send would
give you EIO. That is because is_extent_unchanged had no support for holes
being punched. With this patch, instead of returning EIO we just return
0 (== the extent is not unchanged) and we're good.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Cc: Alexander Block <ablock84@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Btrfs: fix space leak when we fail to reserve metadata space

Dave reported a warning when running xfstest 275.  We have been leaking delalloc
metadata space when our reservations fail.  This is because we were improperly
calculating how much space to free for our checksum reservations.  The problem
is we would sometimes free up space that had already been freed in another
thread and we would end up with negative usage for the delalloc space.  This
patch fixes the problem by calculating how much space the other threads would
have already freed, and then calculate how much space we need to free had we not
done the reservation at all, and then freeing any excess space.  This makes
xfstests 275 no longer have leaked space.  Thanks

Cc: stable@vger.kernel.org
Reported-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Btrfs: fix space accounting for unlink and rename

We are way over-reserving for unlink and rename.  Rename is just some random
huge number and unlink accounts for tree log operations that don't actually
happen during unlink, not to mention the tree log doesn't take from the trans
block rsv anyway so it's completely useless.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Btrfs: hold the ordered operations mutex when waiting on ordered extents

We need to hold the ordered_operations mutex while waiting on ordered extents
since we splice and run the ordered extents list.  We need to make sure anybody
else who wants to wait on ordered extents does actually wait for them to be
completed.  This will keep us from bailing out of flushing in case somebody is
already waiting on ordered extents to complete.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Btrfs: limit the global reserve to 512mb

A user reported a problem where he was getting early ENOSPC with hundreds of
gigs of free data space and 6 gigs of free metadata space.  This is because the
global block reserve was taking up the entire free metadata space.  This is
ridiculous, we have infrastructure in place to throttle if we start using too
much of the global reserve, so instead of letting it get this huge just limit it
to 512mb so that users can still get work done.  This allowed the user to
complete his rsync without issues.  Thanks

Cc: stable@vger.kernel.org
Reported-and-tested-by: Stefan Priebe <s.priebe@profihost.ag>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Btrfs: fix double free in the btrfs_qgroup_account_ref()

The function btrfs_find_all_roots is responsible to allocate
memory for 'roots' and free it if errors happen,so the caller should not
free it again since the work has been done.

Besides,'tmp' is allocated after the function btrfs_find_all_roots,
so we can return directly if btrfs_find_all_roots() fails.

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>
Btrfs: fix wrong reservation of csums

We reserve the space for csums only when we write data into a file, in
the other cases, such as tree log, log replay, we don't do reservation,
so we can use the reservation of the transaction handle just for the former.
And for the latter, we should use the tree's own reservation. But the
function - btrfs_csum_file_blocks() didn't differentiate between these
two types of the cases, fix it.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Btrfs: fix wrong return value of btrfs_lookup_csum()

If we don't find the expected csum item, but find a csum item which is
adjacent to the specified extent, we should return -EFBIG, or we should
return -ENOENT. But btrfs_lookup_csum() return -EFBIG even the csum item
is not adjacent to the specified extent. Fix it.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Btrfs: don't drop path when printing out tree errors in scrub

A user reported a panic where we were panicing somewhere in
tree_backref_for_extent from scrub_print_warning.  He only captured the trace
but looking at scrub_print_warning we drop the path right before we mess with
the extent buffer to print out a bunch of stuff, which isn't right.  So fix this
by dropping the path after we use the eb if we need to.  Thanks,

Cc: stable@vger.kernel.org
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Merge remote-tracking branch 'btrfs-from-mason/for-linus' into 3.8/btrfs-3.9
Merge branch '3.8/btrfs-3.9' into 3.8/my