When the UUID tree is initially created, a task is spawned that
walks through the root tree. For each found subvolume root_item,
the uuid and received_uuid entries in the UUID tree are added.
This is such a quick operation so that in case somebody wants
to unmount the filesystem while the task is still running, the
unmount is delayed until the UUID tree building task is finished.
Signed-off-by: NStefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>
Signed-off-by: NChris Mason <chris.mason@fusionio.com>

This tree is not created by mkfs.btrfs. Therefore when a filesystem
is mounted writable and the UUID tree does not exist, this tree is
created if required. The tree is also added to the fs_info structure
and initialized, but this commit does not yet read or write UUID tree
elements.
Signed-off-by: NStefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>
Signed-off-by: NChris Mason <chris.mason@fusionio.com>

make C=2 fs/btrfs/ CF=-D__CHECK_ENDIAN__

I tried to filter out the warnings for which patches have already
been sent to the mailing list, pending for inclusion in btrfs-next.

All these changes should be obviously safe.
Signed-off-by: NStefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>
Signed-off-by: NChris Mason <chris.mason@fusionio.com>

If we bail out when the stripe alloc fails, we need to undo the
earlier allocation of raid_map.
Signed-off-by: NDave Jones <davej@redhat.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>
Signed-off-by: NChris Mason <chris.mason@fusionio.com>

After reading all device items from the chunk tree, don't
exit the loop and then navigate down the tree again to find
the chunk items. Instead just read all device items and
chunk items with a single tree search. This is possible
because all device items are found before any chunk item in
the chunks tree.
Signed-off-by: NFilipe David Borba Manana <fdmanana@gmail.com>
Reviewed-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>
Signed-off-by: NChris Mason <chris.mason@fusionio.com>

Some codes still use the cpu_to_lexx instead of the
BTRFS_SETGET_STACK_FUNCS declared in ctree.h.

Also added some BTRFS_SETGET_STACK_FUNCS for btrfs_header btrfs_timespec
and other structures.
Signed-off-by: NQu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: NMiao Xie <miaoxie@cn.fujitsu.com>
Reviewed-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>
Signed-off-by: NChris Mason <chris.mason@fusionio.com>

The log message level 'critical' is verbose enough, 'emergency' beeps on
all terminals.
Signed-off-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>
Signed-off-by: NChris Mason <chris.mason@fusionio.com>

Device scanning waits on the uuid_mutex, which can result in a very long
wait if dev delete is shrinking the device.
Signed-off-by: NCarey Underwood <cwillu@cwillu.com>
Reviewed-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>
Signed-off-by: NChris Mason <chris.mason@fusionio.com>

When adjusting the enospc rules for relocation I ran into a deadlock because we
were relocating the only system chunk and that forced us to try and allocate a
new system chunk while holding locks in the chunk tree, which caused us to
deadlock.  To fix this I've moved all of the dev extent addition and chunk
addition out to the delayed chunk completion stuff.  We still keep the in-memory
stuff which makes sure everything is consistent.

One change I had to make was to search the commit root of the device tree to
find a free dev extent, and hold onto any chunk em's that we allocated in that
transaction so we do not allocate the same dev extent twice.  This has the side
effect of fixing a bug with balance that has been there ever since balance
existed.  Basically you can free a block group and it's dev extent and then
immediately allocate that dev extent for a new block group and write stuff to
that dev extent, all within the same transaction.  So if you happen to crash
during a balance you could come back to a completely broken file system.  This
patch should keep these sort of things from happening in the future since we
won't be able to allocate free'd dev extents until after the transaction
commits.  This has passed all of the xfstests and my super annoying stress test
followed by a balance.  Thanks,
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

Now reading the data from the target device of the replace operation is allowed,
so the mirror number that is greater than the stripes number of a chunk is valid,
we will tune it when we find there is no target device later. Fix it.
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

Signed-off-by: NThomas Meyer <thomas@m3y3r.de>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

when user runs command btrfs dev del the raid requisite error if any
goes to the /var/log/messages, its not good idea to clutter messages
with these user (knowledge) errors, further user don't have to review
the system messages to know problem with the cli it should be dropped
to the user as part of the cli return.

to bring this feature created a set of the ERROR defined
BTRFS_ERROR_DEV* error codes and created their error string.

I expect this enum to be added with other error which we might
want to communicate to the user land

v3:
moved the code with in the file no logical change

v1->v2:
introduce error codes for the device mgmt usage

v1:
adds a parameter in the ioctl arg struct to carry the error string
Signed-off-by: NAnand Jain <anand.jain@oracle.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

There are several functions whose code is similar, such as
  btrfs_find_last_root()
  btrfs_read_fs_root_no_radix()

Besides that, some functions are invoked twice, it is unnecessary,
for example, we are sure that all roots which is found in
  btrfs_find_orphan_roots()
have their orphan items, so it is unnecessary to check the orphan
item again.

So cleanup it.
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

Btrfs has been pointer tagging bi_private and using bi_bdev
to store the stripe index and mirror number of failed IOs.

As bios bubble back up through the call chain, we use these
to decide if and how to retry our IOs.  They are also used
to count IO failures on a per device basis.

Recently a bio tracepoint was added lead to crashes because
we were abusing bi_bdev.

This commit adds a btrfs bioset, and creates explicit fields
for the mirror number and stripe index.  The plan is to
extend this structure for all of the fields currently in
struct btrfs_bio, which will mean one less kmalloc in
our IO path.
Signed-off-by: NChris Mason <chris.mason@fusionio.com>
Reported-by: NTejun Heo <tj@kernel.org>

Raid5 with 3 devices is well defined while the old logic allowed
raid5 only with a minimum of 4 devices when converting the block group
profile via btrfs balance. Creating a raid5 with just three devices
using mkfs.btrfs worked always as expected. This is now fixed and the
whole logic is rewritten.
Signed-off-by: NAndreas Philipp <philipp.andreas@gmail.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

Big patch, but all it does is add statics to functions which
are in fact static, then remove the associated dead-code fallout.

removed functions:

btrfs_iref_to_path()
__btrfs_lookup_delayed_deletion_item()
__btrfs_search_delayed_insertion_item()
__btrfs_search_delayed_deletion_item()
find_eb_for_page()
btrfs_find_block_group()
range_straddles_pages()
extent_range_uptodate()
btrfs_file_extent_length()
btrfs_scrub_cancel_devid()
btrfs_start_transaction_lflush()

btrfs_print_tree() is left because it is used for debugging.
btrfs_start_transaction_lflush() and btrfs_reada_detach() are
left for symmetry.

ulist.c functions are left, another patch will take care of those.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NJosef 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: NJosef 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: NMartin Steigerwald <Martin@lichtvoll.de>
Signed-off-by: NJosef 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: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

This:

   # mkfs.btrfs /dev/sdb{1,2} ; wipefs -a /dev/sdb1; mount /dev/sdb2 /mnt/test

would lead to a blkdev open/close mismatch when the mount fails, and
a permanently busy (opened O_EXCL) sdb2:

   # wipefs -a /dev/sdb2
   wipefs: error: /dev/sdb2: probing initialization failed: Device or resource busy

It's because btrfs_open_devices() may open some devices, fail on
the last one, and return that failure stored in "ret."   The mount
then fails, but the caller then does not clean up the open devices.

Chris assures me that:

"btrfs_open_devices just means: go off and open every bdev you can from
this uuid.  It should return success if we opened any of them at all."

So change the logic to ignore any open failures; just skip processing
of that device.  Later on it's decided whether we have enough devices
to continue.
Reported-by: NJan Safranek <jsafrane@redhat.com>
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

A user sent me a btrfs-image of a file system that was panicing on mount during
the log recovery.  I had originally thought these problems were from a bug in
the free space cache code, but that was just a symptom of the problem.  The
problem is if your application does something like this

[prealloc][prealloc][prealloc]

the internal extent maps will merge those all together into one extent map, even
though on disk they are 3 separate extents.  So if you go to write into one of
these ranges the extent map will be right since we use the physical extent when
doing the write, but when we log the extents they will use the wrong sizes for
the remainder prealloc space.  If this doesn't happen to trip up the free space
cache (which it won't in a lot of cases) then you will get bogus entries in your
extent tree which will screw stuff up later.  The data and such will still work,
but everything else is broken.  This patch fixes this by not allowing extents
that are on the modified list to be merged.  This has the side effect that we
are no longer adding everything to the modified list all the time, which means
we now have to call btrfs_drop_extents every time we log an extent into the
tree.  So this allows me to drop all this speciality code I was using to get
around calling btrfs_drop_extents.  With this patch the testcase I've created no
longer creates a bogus file system after replaying the log.  Thanks,
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

With more than one btrfs volume mounted, it can be very difficult to find
out which volume is hitting an error. btrfs_error() will print this, but
it is currently rigged as more of a fatal error handler, while many of
the printk()s are currently for debugging and yet-unhandled cases.

This patch just changes the functions where the device information is
already available. Some cases remain where the root or fs_info is not
passed to the function emitting the error.

This may introduce some confusion with volumes backed by multiple devices
emitting errors referring to the primary device in the set instead of the
one on which the error occurred.

Use btrfs_printk(fs_info, format, ...) rather than writing the device
string every time, and introduce macro wrappers ala XFS for brevity.
Since the function already cannot be used for continuations, print a
newline as part of the btrfs_printk() message rather than at each caller.
Signed-off-by: NSimon Kirby <sim@hostway.ca>
Reviewed-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

Bunch of places in the code weren't using it where they could be -
this'll reduce the size of the patch that puts bi_sector/bi_size/bi_idx
into a struct bvec_iter.
Signed-off-by: NKent Overstreet <koverstreet@google.com>
CC: Jens Axboe <axboe@kernel.dk>
CC: "Ed L. Cashin" <ecashin@coraid.com>
CC: Nick Piggin <npiggin@kernel.dk>
CC: Jiri Kosina <jkosina@suse.cz>
CC: Jim Paris <jim@jtan.com>
CC: Geoff Levand <geoff@infradead.org>
CC: Alasdair Kergon <agk@redhat.com>
CC: dm-devel@redhat.com
CC: Neil Brown <neilb@suse.de>
CC: Steven Rostedt <rostedt@goodmis.org>
Acked-by: NEd Cashin <ecashin@coraid.com>

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: NJosef Bacik <jbacik@fusionio.com>
Signed-off-by: NChris Mason <chris.mason@fusionio.com>

Doing this would reliably fail with -EBUSY for me:

# mount /dev/sdb2 /mnt/scratch; umount /mnt/scratch; mkfs.btrfs -f /dev/sdb2
...
unable to open /dev/sdb2: Device or resource busy

because mkfs.btrfs tries to open the device O_EXCL, and somebody still has it.

Using systemtap to track bdev gets & puts shows a kworker thread doing a
blkdev put after mkfs attempts a get; this is left over from the unmount
path:

btrfs_close_devices
	__btrfs_close_devices
		call_rcu(&device->rcu, free_device);
			free_device
				INIT_WORK(&device->rcu_work, __free_device);
				schedule_work(&device->rcu_work);

so unmount might complete before __free_device fires & does its blkdev_put.

Adding an rcu_barrier() to btrfs_close_devices() causes unmount to wait
until all blkdev_put()s are done, and the device is truly free once
unmount completes.

Cc: stable@vger.kernel.org
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>
Signed-off-by: NChris Mason <chris.mason@fusionio.com>

Raid56 merge (merge commit e942f883) had mistakenly removed a call to
__cancel_balance(), which resulted in balance not cleaning up after itself
after a successful finish.  (Cleanup includes switching the state, removing
the balance item and releasing mut_ex_op testnset lock.)  Bring it back.
Reported-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
Signed-off-by: NChris Mason <chris.mason@fusionio.com>

Btrfs balance can easily hit BUG_ON in these places, but we want
to it bail out gracefully after we force the whole filesystem to
readonly.  So we use btrfs_std_error hook in place of BUG_ON.
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

Dave pointed out that he saw messages from btrfs although there was no
such filesystem on his computers. The automatic device scan is called on
every new blockdevice if the usual distro udev rule set is used. The
printk introduced in 6f60cbd3 was a remainder from copying
portions of code from btrfs_get_bdev_and_sb which is used under
different conditions and the warning makes sense there.
Reported-by: NDave Chinner <dchinner@redhat.com>
Signed-off-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

Though most of the btrfs codes are using ALIGN macro for page alignment,
there are still some codes using open-coded alignment like the
following:
------
        u64 mask = ((u64)root->stripesize - 1);
        u64 ret = (val + mask) & ~mask;
------
Or even hidden one:
------
        num_bytes = (end - start + blocksize) & ~(blocksize - 1);
------

Sometimes these open-coded alignment is not so easy to understand for
newbie like me.

This commit changes the open-coded alignment to the ALIGN macro for a
better readability.

Also there is a previous patch from David Sterba with similar changes,
but the patch is for 3.2 kernel and seems not merged.
http://www.spinics.net/lists/linux-btrfs/msg12747.html

Cc: David Sterba <dave@jikos.cz>
Signed-off-by: NQu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

We try to limit the size of a chunk to 10GB, which keeps the unit of
work reasonable during balance and resize operations.  The limit checks
were taking into account the number of copies of the data we had but
what they really should be doing is comparing against the logical
size of the chunk we're creating.

This moves the code around a little to use the count of data stripes
from raid5/6.
Signed-off-by: NChris Mason <chris.mason@fusionio.com>

__btrfs_close_devices() clones btrfs device structs with
memcpy(). Some of the fields in the clone are reinitialized, but it's
missing to init io_lock. In mainline this goes unnoticed, but on RT it
leaves the plist pointing to the original about to be freed lock
struct.

Initialize io_lock after cloning, so no references to the original
struct are left.
Reported-and-tested-by: NMike Galbraith <efault@gmx.de>
Cc: stable@vger.kernel.org
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NChris Mason <chris.mason@fusionio.com>

super.magic is an le64 but it's treated as an unterminated string when
compared against BTRFS_MAGIC which is defined as a string.  Instead
define BTRFS_MAGIC as a normal hex value and use endian helpers to
compare it to the super's magic.

I tested this by mounting an fs made before the change and made sure
that it didn't introduce sparse errors.  This matches a similar cleanup
that is pending in btrfs-progs.  David Sterba pointed out that we should
fix the kernel side as well :).
Signed-off-by: NZach Brown <zab@redhat.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

Enhance balance usage filter by making it possible to balance out only
completely empty chunks.  Today, usage filter properly acts on values
from 1 to 99 inclusive, usage=100 selects all chunks, and usage=0
selects no chunks.  This commit changes the usage=0 case: the new
meaning is to restripe only completely empty chunks and nothing else.
Suggested-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

Commit 5af3e8cc introduced a use-after-free at volumes.c:3139: bctl is freed
above in __cancel_balance() in all cases except for balance pause.  Fix this
by moving the offending check a couple statements above, the meaning of the
check is preserved.
Reported-by: NChris Mason <chris.mason@fusionio.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

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>

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->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>

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>

btrfs_scan_one_device is calling set_blocksize() which can race
with a concurrent process making dirty page cache pages.  It can end up
dropping dirty page cache pages on the floor, which isn't very nice when
someone is just running btrfs dev scan to find filesystems on the
box.

Now that udev is registering btrfs devices as it discovers them, we can
actually end up racing with our own mkfs program too.  When this
happens, we drop some of the important blocks written by mkfs.

This commit changes scan_one_device to read the super out of the page
cache instead of trying to use bread.  This way we don't have to care
about the blocksize of the device.

This also drops the invalidate_bdev() call.  It wasn't very polite to
invalidate during the scan either.  mkfs is putting the super into the
page cache, there's no reason to invalidate at this point.
Signed-off-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NChris Mason <chris.mason@fusionio.com>