Btrfs: fixup reserved trace points

In trying to track down where we were leaking reserved space I noticed our
reserve extent tracepoints are a little off.  First we were saying that the
reserved space had been alloced in btrfs_reserve_extent, which isn't the case,
this needs to be triggered when we actually allocate the space when we run the
delayed ref.  We were also missing a few places where we should have been
tracing the btrfs_reserve_extent_free tracepoint.  With these in place I was
able to put together where we were leaking reserved space.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Btrfs: free reserved space on error in a few places

While trying to track down a reserved space leak I noticed a few places where we
won't properly clean up reserved space if we have an error, this patch fixes
those up.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Btrfs: add tests for find_lock_delalloc_range

So both Liu and I made huge messes of find_lock_delalloc_range trying to fix
stuff, me first by fixing extent size, then him by fixing something I broke and
then me again telling him to fix it a different way.  So this is obviously a
candidate for some testing.  This patch adds a pseudo fs so we can allocate fake
inodes for tests that need an inode or pages.  Then it addes a bunch of tests to
make sure find_lock_delalloc_range is acting the way it is supposed to.  With
this patch and all of our previous patches to find_lock_delalloc_range I am sure
it is working as expected now.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Btrfs: add tests for btrfs_get_extent

I'm going to be removing hole extents in the near future so I wanted to make a
sanity test for btrfs_get_extent to make sure I don't break anything in the
meantime.  This patch just puts btrfs_get_extent through its paces by giving it
a completely unreasonable mapping to look at and make sure it is giving us back
maps that make sense.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Btrfs: stop all workers after we free block groups

Stefan was hitting a panic in the async worker stuff because we had outstanding
read bios while we were stopping the worker threads.  You could reproduce this
easily if you mount -o nospace_cache and ran generic/273.  This is because the
caching thread stuff is still going and we were stopping all the worker threads.
We need to stop the workers after this work is done, and the free block groups
code will wait for all the caching threads to stop first so we don't run into
this problem.  With this patch we no longer panic.  Thanks,

Cc: stable@vger.kernel.org
Reported-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Btrfs: handle a missing extent for the first file extent

While trying to kill our hole extents I noticed I was seeing problems where we
seek into a file and then start writing and then try to fiemap that file later.
This is because we search for offset 0, don't find anything and so back up one
slot, which puts us at the inode ref or something like that, which means we goto
not_found and create an extent map for our entire search area.  This isn't quite
what we want, we want to move forward one slot and see if there is an extent
there so we can limit our hole extent.  This patch fixes this problem, I will
add a testcase for this as well.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Btrfs: add a sanity test for a vacant extent at the front of a file

Btrfs_get_extent was not handling this case properly, add a test to make sure we
don't regress.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Btrfs: fix hole check in log_one_extent

I added an assert to make sure we were looking up aligned offsets for csums and
I tripped it when running xfstests.  This is because log_one_extent was checking
if block_start == 0 for a hole instead of EXTENT_MAP_HOLE.  This worked out fine
in practice it seems, but it adds a lot of extra work that is uneeded.  With
this fix I'm no longer tripping my assert.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Btrfs: add an assert to btrfs_lookup_csums_range for alignment

I was hitting weird issues when trying to remove hole extents and it turned out
it was because I was sending non-aligned offsets down to
btrfs_lookup_csums_range.  So add an assert for this in case somebody trips over
this in the future.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Btrfs: fix up seek_hole/seek_data handling

Whoever wrote this was braindead.  Also it doesn't work right if you have
VACANCY's since we assumed you would only have that at the end of the file,
which won't be the case in the near future.  I tested this with generic/285 and
generic/286 as well as the btrfs tests that use fssum since it uses
seek_hole/seek_data to verify things are ok.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Btrfs: Simplify the logic in alloc_extent_buffer() for existing extent buffer case

alloc_extent_buffer() uses radix_tree_lookup() when radix_tree_insert()
fails with EEXIST. That part of the code is very similar to the code in
find_extent_buffer(). This patch replaces radix_tree_lookup() and
surrounding code in alloc_extent_buffer() with find_extent_buffer().

Note that radix_tree_lookup() does not need to be protected by
tree->buffer_lock. It is protected by eb->refs.

While at it, this patch
  - changes the other usage of radix_tree_lookup() in alloc_extent_buffer()
    with find_extent_buffer() to reduce redundancy.
  - removes the unused argument 'len' to find_extent_buffer().

Signed-Off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Reviewed-by: Zach Brown <zab@redhat.com>

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Btrfs: remove unnecessary key copy when logging inode

The btrfs_insert_empty_item() function doesn't modify its
key argument.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Reviewed-by: Zach Brown <zab@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Btrfs: cleanup dead code of defragment

@is_extent is no more needed since we don't defrag extent root.

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: kill unused code in btrfs_search_forward

After commit de78b51a2852bddccd6535e9e12de65f92787a1e
(btrfs: remove cache only arguments from defrag path), @blockptr is no more
used.

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: Fix memory leakage in the tree-log.c

In add_inode_ref() function:

Initializes local pointers.

Reduces the logical condition with the __add_inode_ref() return
value by using only one 'goto out'.

Centralizes the exiting, ensuring the freeing of all used memory.

Signed-off-by: Geyslan G. Bem <geyslan@gmail.com>
Reviewed-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Btrfs: nuke a bogus rw_devices decrement in __btrfs_close_devices

On mount failures, __btrfs_close_devices can be called well before
dev-replace state is read and ->is_tgtdev_for_dev_replace is set.  This
leads to a bogus decrement of ->rw_devices and sets off a WARN_ON in
__btrfs_close_devices if replace target device happens to be on the
lists and we fail early in the mount sequence.  Fix this by checking
the devid instead of ->is_tgtdev_for_dev_replace before the decrement:
for replace targets devid is always equal to BTRFS_DEV_REPLACE_DEVID.

Cc: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Btrfs: don't leak ioctl args in btrfs_ioctl_dev_replace

struct btrfs_ioctl_dev_replace_args memory is leaked if replace is
requested on a read-only filesystem.  Fix it.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Btrfs: disallow 'btrfs {balance,replace} cancel' on ro mounts

For both balance and replace, cancelling involves changing the on-disk
state and committing a transaction, which is not a good thing to do on
read-only filesystems.

Cc: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Btrfs: fixup error path in __btrfs_inc_extent_ref

When we fail to add a reference after a non-inline insertion by some reasons,
eg. ENOSPC, we'll abort the transaction, but we don't return this error to
the caller who has to walk around again to find something wrong, that's
unnecessary.

Also fixup other error paths to keep it simple.

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: init device stats for new devices

Device stats are only initialized (read from tree items) on mount.
Trying to read device stats after adding or replacing new devices will
return errors.

btrfs_init_new_device() and btrfs_init_dev_replace_tgtdev() are the two
functions that allocate and initialize new btrfs_device structures after
a filesystem is mounted. They set the device stats to zero by using
kzalloc() which is correct for new devices. The only missing thing was
to declare these stats as being valid (device->dev_stats_valid = 1) and
this patch adds this missing code.

This is the reproducer:

TEST_DEV1=/dev/sdzzzzz1
TEST_DEV2=/dev/sdzzzzz2
TEST_DEV3=/dev/sdzzzzz3
TEST_MNT=/mnt
mkfs.btrfs $TEST_DEV1
mount $TEST_DEV1 $TEST_MNT
btrfs device add $TEST_DEV2 $TEST_MNT
btrfs device stat $TEST_MNT
btrfs replace start -B $TEST_DEV2 $TEST_DEV3 $TEST_MNT
btrfs device stat $TEST_MNT
umount $TEST_MNT

Reported-by: Ondrej Kunc <kunc88@gmail.com>
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>