Removed unused #include <version.h>'s in btrfs
Signed-off-by: NHuang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>

Andrew's review of the xattr code revealed some minor issues that this patch
addresses.  Just an error return fix, got rid of a useless statement and
commented one of the trickier parts of __btrfs_getxattr.
Signed-off-by: NJosef Bacik <jbacik@redhat.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>

- Remove the unused local variable 'len';
- Check return value of kmalloc().
Signed-off-by: NWang Cong <wangcong@zeuux.org>
Signed-off-by: NChris Mason <chris.mason@oracle.com>

The structure used to send device in btrfs ioctl calls was not
properly aligned, and so 32 bit ioctls would not work properly on
64 bit kernels.

We could fix this with compat ioctls, but we're just one byte away
and it doesn't make sense at this stage to carry about the compat ioctls
forever at this stage in the project.

This patch brings the ioctl arg up to an evenly aligned 4k.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

Btrfs maintains a queue of async bio submissions so the checksumming
threads don't have to wait on get_request_wait.  In order to avoid
extra wakeups, this code has a running_pending flag that is used
to tell new submissions they don't need to wake the thread.

When the threads notice congestion on a single device, they
may decide to requeue the job and move on to other devices.  This
makes sure the running_pending flag is cleared before the
job is requeued.

It should help avoid IO stalls by making sure the task is woken up
when new submissions come in.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

Each subvolume has an extent_state_tree used to mark metadata
that needs to be sent to disk while syncing the tree.  This is
used in addition to the dirty bits on the pages themselves so that
a single subvolume can be sent to disk efficiently in disk order.

Normally this marking happens in btrfs_alloc_free_block, which also does
special recording of dirty tree blocks for the tree log roots.

Yan Zheng noticed that when the root of the log tree is allocated, it is added
to the wrong writeback list.  The fix used here is to explicitly set
it dirty as part of tree log creation.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

This is already in the arch specific directories in mainline and
shouldn't be copied into btrfs.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

Signed-off-by: NChris Mason <chris.mason@oracle.com>

None of the checksum verification code schedules, so we can use the faster
kmap_atomic
Signed-off-by: NChris Mason <chris.mason@oracle.com>

Checksum verification happens in a helper thread, and there is no
need to mess with interrupts.  This switches to kmap() instead.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

This patch contains following things.

1) Limit the max size of btrfs_ordered_sum structure to PAGE_SIZE.  This
struct is kmalloced so we want to keep it reasonable.

2) Replace copy_extent_csums by btrfs_lookup_csums_range.  This was
duplicated code in tree-log.c

3) Remove replay_one_csum. csum items are replayed at the same time as
   replaying file extents. This guarantees we only replay useful csums.

4) nbytes accounting fix.
Signed-off-by: NYan Zheng <zheng.yan@oracle.com>

btrfs_drop_extents doesn't change file extent's ram_bytes
in the case of booked extent. To be consistent, we should
also not change ram_bytes when truncating existing extent.
Signed-off-by: NYan Zheng <zheng.yan@oracle.com>

Snapshot creation happens at a specific time during transaction commit.  We
need to make sure the code called by snapshot creation doesn't wait
for the running transaction to commit.

This changes btrfs_delete_inode and finish_pending_snaps to use
btrfs_join_transaction instead of btrfs_start_transaction to avoid deadlocks.

It would be better if btrfs_delete_inode didn't use the join, but the
call path that triggers it is:

btrfs_commit_transaction->create_pending_snapshots->
create_pending_snapshot->btrfs_lookup_dentry->
fixup_tree_root_location->btrfs_read_fs_root->
btrfs_read_fs_root_no_name->btrfs_orphan_cleanup->iput

This will be fixed in a later patch by moving the orphan cleanup to the
cleaner thread.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

Signed-off-by: NChris Mason <chris.mason@oracle.com>

They should stay out until this is turned into generic code.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

There were many, most are fixed now.  struct-funcs.c generates some warnings
but these are bogus.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

This is a patch to fix discard semantic to make Btrfs work with FTL and SSD.
We can improve FTL's performance by telling it which sectors are freed by file
system. But if we don't tell FTL the information of free sectors in proper
time, the transaction mechanism of Btrfs will be destroyed and Btrfs could not
roll back the previous transaction under the power loss condition.

There are some problems in the old implementation:
1, In __free_extent(), the pinned down extents should not be discarded.
2, In free_extents(), the free extents are all pinned, so they need to
be discarded in transaction committing time instead of free_extents().
3, The reserved extent used by log tree should be discard too.

This patch change discard behavior as follows:
1, For the extents which need to be free at once,
   we discard them in update_block_group().
2, Delay discarding the pinned extent in btrfs_finish_extent_commit()
   when committing transaction.
3, Remove discarding from free_extents() and __free_extent()
4, Add discard interface into btrfs_free_reserved_extent()
5, Discard sectors before updating the free space cache, otherwise,
   FTL will destroy file system data.

drop_one_dir_item does not properly update inode's link count. It can be
reproduced by executing following commands:

#touch test
#sync
#rm -f test
#dd if=/dev/zero bs=4k count=1 of=test conv=fsync
#echo b > /proc/sysrq-trigger

This fixes it by adding an BTRFS_ORPHAN_ITEM_KEY for the inode
Signed-off-by: NYan Zheng <zheng.yan@oracle.com>

The data in fs_info->super_for_commit are zeros before the
first transaction commit. If tree log sync and system crash
both occur before the first transaction commit, super block
will get corrupted.

This fixes it by properly filling in the super_for_commit field at
open time.
Signed-off-by: NYan Zheng <zheng.yan@oracle.com>

Signed-off-by: NShen Feng <shen@cn.fujitsu.com>

subvol_name should be freed if error occurs.
Signed-off-by: NShen Feng <shen@cn.fujitsu.com>

In clear_state_cb, we should check 'tree->ops->clear_bit_hook' instead
of 'tree->ops->set_bit_hook'.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

Signed-off-by: NChris Mason <chris.mason@oracle.com>

Make sure directory's size properly updated when creating
subvol/snapshot.
Signed-off-by: NYan Zheng <zheng.yan@oracle.com>

Only root can add/remove devices
Only root can defrag subtrees
Only files open for writing can be defragged
Only files open for writing can be the destination for a clone
Signed-off-by: NChris Mason <chris.mason@oracle.com>

Signed-off-by: NChris Mason <chris.mason@oracle.com>

There is a race in relocate_inode_pages, it happens when
find_delalloc_range finds the delalloc extent before the
boundary bit is set. Thank you,
Signed-off-by: NYan Zheng <zheng.yan@oracle.com>

This adds the missing block accounting code to finish_current_insert and makes
block accounting for root item properly protected by the delalloc spin lock.
Signed-off-by: NYan Zheng <zheng.yan@oracle.com>

This patch adds the missing mnt_drop_write to match
mnt_want_write in btrfs_ioctl_defrag and btrfs_ioctl_clone
Signed-off-by: NYan Zheng <zheng.yan@oracle.com>

The return value was being overwritten.
Signed-off-by: NYehuda Sadeh <yehuda@hq.newdream.net>

bio_end_io for reads without checksumming on and btree writes were
happening without using async thread pools.  This means the extent_io.c
code had to use spin_lock_irq and friends on the rb tree locks for
extent state.

There were some irq safe vs unsafe lock inversions between the delallock
lock and the extent state locks.  This patch gets rid of them by moving
all end_io code into the thread pools.

To avoid contention and deadlocks between the data end_io processing and the
metadata end_io processing yet another thread pool is added to finish
off metadata writes.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

btrfs_insert_empty_items takes the space needed by the btrfs_item
structure into account when calculating the required free space.

So the tree balancing code shouldn't add sizeof(struct btrfs_item)
to the size when checking the free space. This patch removes these
superfluous additions.
Signed-off-by: NYan Zheng <zheng.yan@oracle.com>

Btrfs maintains a cache of blocks available for allocation in ram.  The
code that frees extents was marking the extents free and then deleting
the checksum items.

This meant it was possible the extent would be reallocated before the
checksum item was actually deleted, leading to races and other
problems as the checksums were updated for the newly allocated extent.

The fix is to delete the checksum before marking the extent free.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

The delalloc lock doesn't need to have irqs disabled, nobody that
changes the number of delalloc bytes in the FS is running with irqs off.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

The compression code was using isize to limit the amount of data it
sent through zlib.  But, it wasn't properly limiting the looping to
just the pages inside i_size.  The end result was trying to compress
too many pages, including those that had not been setup and properly locked
down.  This made the compression code oops while trying find_get_page on a
page that didn't exist.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

Checksums on data can be disabled by mount option, so it's
possible some data extents don't have checksums or have
invalid checksums. This causes trouble for data relocation.
This patch contains following things to make data relocation
work.

1) make nodatasum/nodatacow mount option only affects new
files. Checksums and COW on data are only controlled by the
inode flags.

2) check the existence of checksum in the nodatacow checker.
If checksums exist, force COW the data extent. This ensure that
checksum for a given block is either valid or does not exist.

3) update data relocation code to properly handle the case
of checksum missing.
Signed-off-by: NYan Zheng <zheng.yan@oracle.com>

This patch makes seed device possible to be shared by
multiple mounted file systems. The sharing is achieved
by cloning seed device's btrfs_fs_devices structure.
Thanks you,
Signed-off-by: NYan Zheng <zheng.yan@oracle.com>

The block group structs are referenced in many different
places, and it's not safe to free while balancing.  So, those block
group structs were simply leaked instead.

This patch replaces the block group pointer in the inode with the starting byte
offset of the block group and adds reference counting to the block group
struct.
Signed-off-by: NYan Zheng <zheng.yan@oracle.com>

Add missing mnt_drop_write to match the mnt_want_write in
btrfs_ioctl_trans_start.
Signed-off-by: NSage Weil <sage@newdream.net>

This updates the space balancing code for the
new checksum format.
Signed-off-by: NYan Zheng <zheng.yan@oracle.com>