WARN_ON isn't enough, we need to stop the loop if for any reason
we would overrun the devices_info array.

I tried to track down the connection between the length of
the alloc_devices list and the rw_devices counter but
it wasn't immediately obvious, so be defensive about it.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

No point in DEFINE_WAIT(wait) if it's not used!
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

"item" was set but never used in this function.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

__btrfs_std_error didn't always properly call va_end,
and might call va_start even if fmt was NULL.

Move all the varargs handling into the block where we
have fmt.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

I don't think that BTRFS_DEV_EXTENT_KEY is supposed
to fall through to BTRFS_DEV_STATS_KEY ...
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

This keeps static checkers happy.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

At least backref_tree_panic() can apparently pass
in a null fs_info, so handle that in __btrfs_panic
to get the message out on the console.

The btrfs_panic macro also uses fs_info, but that's
largely pointless; it's testing to see if
BTRFS_MOUNT_PANIC_ON_FATAL_ERROR is not set.
But if it *were* set, __btrfs_panic() would have,
well, paniced and we wouldn't be here, testing it!
So just BUG() at this point.

And since we only use fs_info once now, just use it
directly.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

No need to test the result, we can't get a
null pointer from list_entry()
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

All we do is set it to NULL and test it :)
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

Because of how little we allocate chunks now we can get really tight on
metadata space before we will allocate a new chunk.  This resulted in being
unable to add device extents when allocating a new metadata chunk as we did
not have enough space.  This is because we were allowed to overcommit too
much metadata without actually making sure we had enough space to make
allocations.  The idea behind overcommit is that we are allowed to say "sure
you can have that reservation" when most of the free space is occupied by
reservations, not actual allocations.  But in this case where a majority of
the total space is in use by actual allocations we can screw ourselves by
not being able to make real allocations when it matters.  So make sure we
have enough real space for our global reserve, and if not then don't allow
overcommitting.  Thanks,
Reported-and-tested-by: NJim Schutt <jaschut@sandia.gov>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

I got a double free error when unmounting a file system that failed to add a
chunk during its operation.  This is because we will kfree the mapping that
we created but leave the extent_map in the em_tree for chunks.  So to fix
this just remove the extent_map when we error out so we don't run into this
problem.  Thanks,
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

If we error out allocating a dev extent we will have already created the
block group and such which will cause problems since the allocator may have
tried to allocate out of the block group that no longer exists.  This will
cause BUG_ON()'s in the bio submission path.  This also makes a failure to
allocate a dev extent a non-abort error, we will just clean up the dev
extents we did allocate and exit.  Now if we fail to delete the dev extents
we will abort since we can't have half of the dev extents hanging around,
but this will make us much less likely to abort.  Thanks,
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

There is no lock to protect fs_info->fs_state, it will introduce
some problems, such as the value may be covered by the other task
when several tasks modify it. For example:
	Task0 - CPU0		Task1 - CPU1
	mov %fs_state rax
	or $0x1 rax
				mov %fs_state rax
				or $0x2 rax
	mov rax %fs_state
				mov rax %fs_state
The expected value is 3, but in fact, it is 2.

Though this problem doesn't happen now (because there is only one
flag currently), the code is error prone, if we add other flags,
the above problem will happen to a certainty.

Now we use bit operation for it to fix the above problem.
In this way, we can make the code more robust and be easy to
add new flags.
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

There is no lock to protect
  fs_info->avail_{data, metadata, system}_alloc_bits,
it may introduce some problem, such as the wrong profile
information, so we add a seqlock to protect them.
Signed-off-by: NZhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

We need not use a global lock to protect the delalloc_bytes of the
inode, just use its own lock. In this way, we can reduce the lock
contention and ->delalloc_lock will just protect delalloc inode
list.
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

fs_info->delalloc_bytes is accessed very frequently, so use percpu
counter instead of the u64 variant for it to reduce the lock
contention.

This patch also fixed the problem that we access the variant
without the lock protection.At worst, we would not flush the
delalloc inodes, and just return ENOSPC error when we still have
some free space in the fs.
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

->dirty_metadata_bytes is accessed very frequently, so use percpu
counter instead of the u64 variant to reduce the contention of
the lock.

This patch also fixed the problem that we access it without
lock protection in __btrfs_btree_balance_dirty(), which may
cause we skip the dirty pages flush.
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

fs_info->alloc_start is a 64bits variant, can be accessed by
multi-task, but it is not protected strictly, it can be changed
while we are accessing it. On 32bit machine, we will get wrong
value because we access it by two instructions.(In fact, it is
also possible that the same problem happens on the 64bit machine,
because the compiler may split the 64bit operation into two 32bit
operation.)

For example:
Assuming -> alloc_start is 0x0000 0000 0001 0000 at the beginning,
then we remount and set ->alloc_start to 0x0000 0100 0000 0000.
	Task0 			Task1
				load high 32 bits
	set high 32 bits
	set low 32 bits
				load low 32 bits

Task1 will get 0.

This patch fixes this problem by using two locks to protect it
	fs_info->chunk_mutex
	sb->s_umount
On the read side, we just need get one of these two locks, and on
the write side, we must lock all of them.
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

Though ->max_inline is a 64bit variant, and may be accessed by
multi-task, but it is just suggestive number, so we needn't add
anything to protect fs_info->max_inline, just add a comment to
explain wny we don't use a lock to protect it.
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

The header file will then be installed under /usr/include/linux so that
userspace applications can refer to Btrfs ioctls by name and use the same
structs used internally in the kernel.
Signed-off-by: NFilipe Brandenburger <filbranden@google.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

CAP_DAC_READ_SEARCH overrides read and search permission check on
file and directory. It seems fit for BTRFS_IOC_INO_PATHS.
Signed-off-by: NKusanagi Kouichi <slash@ac.auone-net.jp>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

This reverts commit 2794ed01.

Wasn't supposed to get used in btrfs_mknod, it was supposed to be in
btrfs_create, which was done in commit
9185aa58.
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

btrfs_run_ordered_operations() needn't traverse the ordered operation list
repeatedly, it is because the transaction commiter will invoke it again when
there is no other writer in this transaction, it can ensure that no one can
add new objects into the ordered operation list.
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

btrfs_start_delalloc_inodes() needn't traverse and flush the delalloc inodes
repeatedly. It is because we can regard the data that the users write after
we start delalloc inodes flush as the one which is after the delalloc inodes
flush is done, and we can flush it next time.
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

We forget to check the return value of btrfs_run_ordered_operations() when
flushing all the pending stuffs, fix it.
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

We forget to check the return value of btrfs_start_delalloc_inodes(), fix it.
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

The current code of raid attr arry is hard to understand and it is easy to
introduce some problem if we modify the array. So I changed it and made it
more readable.

Cc: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

This'd save us a rbtree search which may become expensive in large filesystem.
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

This does not change the logic of code, but can save us a read_lock.
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

The API in tree log code has done sort of changes, and it proves that
we can benifit from using token, so do the same thing here.

function_graph tracer's timer shows that it costs nearly half time
of before(39.788us -> 22.391us).
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

Argument 'trans' is not used any more.
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

Argument 'trans' is not used any more.
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

Argument 'trans' and 'root' are not used any more.
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

commit d53ba474
(Btrfs: use commit root when loading free space cache) has remove
the deadlock check, and the related comments can be removed as well.
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Reviewed-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

If we start running low on metadata space we will try to allocate a chunk,
which could then try to allocate a chunk to add the device entry.  The thing
is we allocate a chunk before we try really hard to make the allocation, so
we should be able to find space for the device entry.  Add a flag to the
trans handle so we know we're currently allocating a chunk so we can just
bail out if we try to allocate another chunk.  Thanks,
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

Since we don't actually copy the extent information from the source tree in
the fast case we don't need to wait for ordered io to be completed in order
to fsync, we just need to wait for the io to be completed.  So when we're
logging our file just attach all of the ordered extents to the log, and then
when the log syncs just wait for IO_DONE on the ordered extents and then
write the super.  Thanks,
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

This patch fixes the following problem:
- improper return value
- unnecessary read-only check
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

Use wrapper page_offset to get byte-offset into filesystem object for page.
Signed-off-by: NLiu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

We may try to flush some dirty pages when there is no enough space to reserve.
But it is possible that this operation fails, in order to get enough space to
reserve successfully, we will sync all the delalloc file. This operation is
safe, we needn't worry about the case that the filesystem goes from r/w to r/o.
because the filesystem should guarantee all the dirty pages have been written
into the disk after it becomes readonly, so the sync operation will do nothing
if the filesystem is already readonly. Though it may waste lots of time,
as a corner case, we needn't care.
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>