Commit Graph

5713 Commits

Author SHA1 Message Date
Jeff Mahoney
cea67ab92d btrfs: clean the old superblocks before freeing the device
btrfs_rm_device frees the block device but then re-opens it using
the saved device name.  A race exists between the close and the
re-open that allows the block size to be changed.  The result
is getting stuck forever in the reclaim loop in __getblk_slow.

This patch moves the superblock cleanup before closing the block
device, which is also consistent with other callers.  We also don't
need a private copy of dev_name as the whole routine operates under
the uuid_mutex.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-26 18:08:44 +02:00
Liu Bo
02794222c4 Btrfs: kill BUG_ON in run_delayed_tree_ref
In a corrupted btrfs image, we can come across this BUG_ON and
get an unreponsive system, but if we return errors instead,
its caller can handle everything gracefully by aborting the current
transaction.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-26 18:08:44 +02:00
Josef Bacik
6bdf131fac Btrfs: don't leak reloc root nodes on error
We don't track the reloc roots in any sort of normal way, so the only way the
root/commit_root nodes get free'd is if the relocation finishes successfully and
the reloc root is deleted.  Fix this by free'ing them in free_reloc_roots.
Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-26 18:08:44 +02:00
Masahiro Yamada
e2c8990734 btrfs: squash lines for simple wrapper functions
Remove unneeded variables and assignments.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-26 18:08:38 +02:00
Liu Bo
6b722c1747 Btrfs: improve check_node to avoid reading corrupted nodes
We need to check items in a node to make sure that we're reading
a valid one, otherwise we could get various crashes while processing
delayed_refs.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-26 18:05:28 +02:00
Liu Bo
a42cbec9c6 Btrfs: add error handling for extent buffer in print tree
Somehow we missed btrfs_print_tree when last time we
updated error handling for read_extent_block().

This keeps us from getting a NULL pointer panic when
btrfs_print_tree's read_extent_block() fails.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-26 18:04:01 +02:00
Liu Bo
a43f7f8206 Btrfs: remove BUG_ON in start_transaction
Since we could get errors from the concurrent aborted transaction,
the check of this BUG_ON in start_transaction is not true any more.

Say, while flushing free space cache inode's dirty pages,
btrfs_finish_ordered_io
 -> btrfs_join_transaction_nolock
      (the transaction has been aborted.)
      -> BUG_ON(type == TRANS_JOIN_NOLOCK);

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-26 18:04:01 +02:00
Liu Bo
3eb548ee3a Btrfs: memset to avoid stale content in btree node block
During updating btree, we could push items between sibling
nodes/leaves, for leaves data sections starts reversely from
the end of the block while for nodes we only have key pairs
which are stored one by one from the start of the block.

So we could do try to push key pairs from one node to the next
node right in the tree, and after that, we update the node's
nritems to reflect the correct end while leaving the stale
content in the node.  One may intentionally corrupt the fs
image and access the stale content by bumping the nritems and
causes various crashes.

This takes the in-memory @nritems as the correct one and
gets to memset the unused part of a btree node.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-26 18:03:47 +02:00
Liu Bo
3561b9db70 Btrfs: return gracefully from balance if fs tree is corrupted
When relocating tree blocks, we firstly get block information from
back references in the extent tree, we then search fs tree to try to
find all parents of a block.

However, if fs tree is corrupted, eg. if there're some missing
items, we could come across these WARN_ONs and BUG_ONs.

This makes us print some error messages and return gracefully
from balance.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-26 17:59:49 +02:00
Josef Bacik
9c8e63db1d Btrfs: kill BUG_ON()'s in btrfs_mark_extent_written
No reason to bug on in here, fs corruption could easily cause these things to
happen.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-26 17:59:49 +02:00
Josef Bacik
8436ea91a1 Btrfs: kill the start argument to read_extent_buffer_pages
Nobody uses this, it makes no sense to do partial reads of extent buffers.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-26 17:59:49 +02:00
Josef Bacik
afcdd129e0 Btrfs: add a flags field to btrfs_fs_info
We have a lot of random ints in btrfs_fs_info that can be put into flags.  This
is mostly equivalent with the exception of how we deal with quota going on or
off, now instead we set a flag when we are turning it on or off and deal with
that appropriately, rather than just having a pending state that the current
quota_enabled gets set to.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-26 17:59:49 +02:00
Qu Wenruo
ba8b04c1d4 btrfs: extend btrfs_set_extent_delalloc and its friends to support in-band dedupe and subpage size patchset
Extend btrfs_set_extent_delalloc() and extent_clear_unlock_delalloc()
parameters for both in-band dedupe and subpage sector size patchset.

This should reduce conflict of both patchset and the effort to rebase
them.

Cc: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Cc: David Sterba <dsterba@suse.cz>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-26 17:59:49 +02:00
Jeff Mahoney
897a41b116 btrfs: add dynamic debug support
We can re-use the dynamic debugging descriptor to make use of the dynamic
debugging mechanism but still use our own printk interface.

Defining the DEBUG macro works as it did before.  When it's defined,
all of the messages default to print.  We can also enable all debug
messages at boot or module-load time using the 'dyndbg' and
'btrfs.dyndbg' options.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-26 17:59:49 +02:00
Luis Henriques
2309e79650 btrfs: Fix warning "variable ‘gen’ set but not used"
Variable 'gen' in reada_for_search() is not used since commit 58dc4ce432
("btrfs: remove unused parameter from readahead_tree_block").  This patch
simply removes this variable.

Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-26 17:59:49 +02:00
Luis Henriques
1f079fa2f8 btrfs: Fix warning "variable ‘blocksize’ set but not used"
Variable 'blocksize' in reada_walk_down() is not used since commit
d3e46fea1b ("btrfs: sink blocksize parameter to readahead_tree_block").
This patch simply removes this variable.

Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-26 17:59:49 +02:00
Naohiro Aota
5d8eb6fe51 btrfs: let btrfs_delete_unused_bgs() to clean relocated bgs
Currently, btrfs_relocate_chunk() is removing relocated BG by itself. But
the work can be done by btrfs_delete_unused_bgs() (and it's better since it
trim the BG). Let's dedupe the code.

While btrfs_delete_unused_bgs() is already hitting the relocated BG, it
skip the BG since the BG has "ro" flag set (to keep balancing BG intact).
On the other hand, btrfs cannot drop "ro" flag here to prevent additional
writes. So this patch make use of "removed" flag.
btrfs_delete_unused_bgs() now detect the flag to distinguish whether a
read-only BG is relocating or not.

Signed-off-by: Naohiro Aota <naohiro.aota@hgst.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-26 17:59:49 +02:00
Liu Bo
49303381f1 Btrfs: bail out if block group has different mixed flag
Currently we allow inconsistence about mixed flag
 (BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA).

We'd get ENOSPC if block group has mixed flag and btrfs doesn't.
If that happens, we have one space_info with mixed flag and another
space_info only with BTRFS_BLOCK_GROUP_METADATA, and
global_block_rsv.space_info points to the latter one, but all bytes
from block_group contributes to the mixed space_info, thus all the
allocation will fail with ENOSPC.

This adds a check for the above case.

Reported-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
[ updated message ]
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-26 17:59:49 +02:00
Liu Bo
2571e73967 Btrfs: fix memory leak in reading btree blocks
So we can read a btree block via readahead or intentional read,
and we can end up with a memory leak when something happens as
follows,
1) readahead starts to read block A but does not wait for read
   completion,
2) btree_readpage_end_io_hook finds that block A is corrupted,
   and it needs to clear all block A's pages' uptodate bit.
3) meanwhile an intentional read kicks in and checks block A's
   pages' uptodate to decide which page needs to be read.
4) when some pages have the uptodate bit during 3)'s check so
   3) doesn't count them for eb->io_pages, but they are later
   cleared by 2) so we has to readpage on the page, we get
   the wrong eb->io_pages which results in a memory leak of
   this block.

This fixes the problem by firstly getting all pages's locking and
then checking pages' uptodate bit.

   t1(readahead)                              t2(readahead endio)                                       t3(the following read)
read_extent_buffer_pages                    end_bio_extent_readpage
  for pg in eb:                                for page 0,1,2 in eb:
      if pg is uptodate:                           btree_readpage_end_io_hook(pg)
          num_reads++                              if uptodate:
  eb->io_pages = num_reads                             SetPageUptodate(pg)              _______________
  for pg in eb:                                for page 3 in eb:                                     read_extent_buffer_pages
       if pg is NOT uptodate:                      btree_readpage_end_io_hook(pg)                       for pg in eb:
           __extent_read_full_page(pg)                 sanity check reports something wrong                 if pg is uptodate:
                                                       clear_extent_buffer_uptodate(eb)                         num_reads++
                                                           for pg in eb:                                eb->io_pages = num_reads
                                                               ClearPageUptodate(page)  _______________
                                                                                                        for pg in eb:
                                                                                                            if pg is NOT uptodate:
                                                                                                                __extent_read_full_page(pg)

So t3's eb->io_pages is not consistent with the number of pages it's reading,
and during endio(), atomic_dec_and_test(&eb->io_pages) will get a negative
number so that we're not able to free the eb.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-26 17:59:49 +02:00
Liu Bo
e46a28ca3d Btrfs: remove BUG() in raid56
This BUG() has been triggered by a fuzz testing image, which contains
an invalid chunk type, ie. a single stripe chunk has the raid6 type.

Btrfs can handle this gracefully by returning -EIO, so besides using
btrfs_warn to give us more debugging information rather than a single
BUG(), we can return error properly.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-26 17:59:49 +02:00
Lu Fengqi
afce772e87 btrfs: fix check_shared for fiemap ioctl
Only in the case of different root_id or different object_id, check_shared
identified extent as the shared. However, If a extent was referred by
different offset of same file, it should also be identified as shared.
In addition, check_shared's loop scale is at least n^3, so if a extent
has too many references, even causes soft hang up.

First, add all delayed_ref to the ref_tree and calculate the unqiue_refs,
if the unique_refs is greater than one, return BACKREF_FOUND_SHARED.
Then individually add the on-disk reference(inline/keyed) to the ref_tree
and calculate the unique_refs of the ref_tree to check if the unique_refs
is greater than one.Because once there are two references to return
SHARED, so the time complexity is close to the constant.

Reported-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-26 17:59:49 +02:00
David Sterba
b0de6c4c81 btrfs: create example debugfs file only in debugging build
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-26 17:59:49 +02:00
Eric Sandeen
07f6a48043 btrfs: fix perms on demonstration debugfs interface
btrfs provides a helpful demonstration of how to export
a global variable via debugfs; however, it is unique among
other debugfs files in that it is world-writable, which causes
some concern to people who are not familiar with its purpose.

Fix it so that it is only user-writable.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-26 17:59:49 +02:00
Liu Bo
c79a175175 Btrfs: fix memory leak of block group cache
While processing delayed refs, we may update block group's statistics
and attach it to cur_trans->dirty_bgs, and later writing dirty block
groups will process the list, which happens during
btrfs_commit_transaction().

For whatever reason, the transaction is aborted and dirty_bgs
is not processed in cleanup_transaction(), we end up with memory leak
of these dirty block group cache.

Since btrfs_start_dirty_block_groups() doesn't make it go to the commit
critical section, this also adds the cleanup work inside it.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-26 17:59:49 +02:00
Linus Torvalds
b22734a550 Merge branch 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "Josef fixed a problem when quotas are enabled with his latest ENOSPC
  rework, and Jeff added more checks into the subvol ioctls to avoid
  tripping up lookup_one_len"

* 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  btrfs: ensure that file descriptor used with subvol ioctls is a dir
  Btrfs: handle quota reserve failure properly
2016-09-23 13:39:37 -07:00
Jan Kara
31051c85b5 fs: Give dentry to inode_change_ok() instead of inode
inode_change_ok() will be resposible for clearing capabilities and IMA
extended attributes and as such will need dentry. Give it as an argument
to inode_change_ok() instead of an inode. Also rename inode_change_ok()
to setattr_prepare() to better relect that it does also some
modifications in addition to checks.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2016-09-22 10:56:19 +02:00
Jan Kara
073931017b posix_acl: Clear SGID bit when setting file permissions
When file permissions are modified via chmod(2) and the user is not in
the owning group or capable of CAP_FSETID, the setgid bit is cleared in
inode_change_ok().  Setting a POSIX ACL via setxattr(2) sets the file
permissions as well as the new ACL, but doesn't clear the setgid bit in
a similar way; this allows to bypass the check in chmod(2).  Fix that.

References: CVE-2016-7097
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2016-09-22 10:55:32 +02:00
Jeff Mahoney
325c50e3ce btrfs: ensure that file descriptor used with subvol ioctls is a dir
If the subvol/snapshot create/destroy ioctls are passed a regular file
with execute permissions set, we'll eventually Oops while trying to do
inode->i_op->lookup via lookup_one_len.

This patch ensures that the file descriptor refers to a directory.

Fixes: cb8e70901d (Btrfs: Fix subvolume creation locking rules)
Fixes: 76dda93c6a (Btrfs: add snapshot/subvolume destroy ioctl)
Cc: <stable@vger.kernel.org> #v2.6.29+
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2016-09-21 17:22:16 -07:00
Josef Bacik
1e5ec2e709 Btrfs: handle quota reserve failure properly
btrfs/022 was spitting a warning for the case that we exceed the quota.  If we
fail to make our quota reservation we need to clean up our data space
reservation.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Tested-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2016-09-21 17:22:16 -07:00
Miklos Szeredi
f031221001 btrfs: use filemap_check_errors()
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Cc: Chris Mason <clm@fb.com>
2016-09-16 12:44:21 +02:00
Bart Van Assche
4382e33ad3 block, dm-crypt, btrfs: Introduce bio_flags()
Introduce the bio_flags() macro. Ensure that the second argument of
bio_set_op_attrs() only contains flags and no operation. This patch
does not change any functionality.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Mike Christie <mchristi@redhat.com>
Cc: Chris Mason <clm@fb.com> (maintainer:BTRFS FILE SYSTEM)
Cc: Josef Bacik <jbacik@fb.com> (maintainer:BTRFS FILE SYSTEM)
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Damien Le Moal <damien.lemoal@hgst.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-09-14 08:48:27 -06:00
Linus Torvalds
f4a9c169c2 Merge branch 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "I'm not proud of how long it took me to track down that one liner in
  btrfs_sync_log(), but the good news is the patches I was trying to
  blame for these problems were actually fine (sorry Filipe)"

* 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  btrfs: introduce tickets_id to determine whether asynchronous metadata reclaim work makes progress
  btrfs: remove root_log_ctx from ctx list before btrfs_sync_log returns
  btrfs: do not decrease bytes_may_use when replaying extents
2016-09-09 12:52:31 -07:00
Chris Mason
b7f3c7d345 Merge branch 'for-chris' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.8 2016-09-07 12:55:36 -07:00
Wang Xiaoguang
ce129655c9 btrfs: introduce tickets_id to determine whether asynchronous metadata reclaim work makes progress
In btrfs_async_reclaim_metadata_space(), we use ticket's address to
determine whether asynchronous metadata reclaim work is making progress.

	ticket = list_first_entry(&space_info->tickets,
				  struct reserve_ticket, list);
	if (last_ticket == ticket) {
		flush_state++;
	} else {
		last_ticket = ticket;
		flush_state = FLUSH_DELAYED_ITEMS_NR;
		if (commit_cycles)
			commit_cycles--;
	}

But indeed it's wrong, we should not rely on local variable's address to
do this check, because addresses may be same. In my test environment, I
dd one 168MB file in a 256MB fs, found that for this file, every time
wait_reserve_ticket() called, local variable ticket's address is same,

For above codes, assume a previous ticket's address is addrA, last_ticket
is addrA. Btrfs_async_reclaim_metadata_space() finished this ticket and
wake up it, then another ticket is added, but with the same address addrA,
now last_ticket will be same to current ticket, then current ticket's flush
work will start from current flush_state, not initial FLUSH_DELAYED_ITEMS_NR,
which may result in some enospc issues(I have seen this in my test machine).

Signed-off-by: Wang Xiaoguang <wangxg.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-06 16:31:43 +02:00
Chris Mason
cbd60aa7cd Btrfs: remove root_log_ctx from ctx list before btrfs_sync_log returns
We use a btrfs_log_ctx structure to pass information into the
tree log commit, and get error values out.  It gets added to a per
log-transaction list which we walk when things go bad.

Commit d1433debe added an optimization to skip waiting for the log
commit, but didn't take root_log_ctx out of the list.  This
patch makes sure we remove things before exiting.

Signed-off-by: Chris Mason <clm@fb.com>
Fixes: d1433debe7
cc: stable@vger.kernel.org # 3.15+
2016-09-06 05:57:25 -07:00
Wang Xiaoguang
ed7a694839 btrfs: do not decrease bytes_may_use when replaying extents
When replaying extents, there is no need to update bytes_may_use
in btrfs_alloc_logged_file_extent(), otherwise it'll trigger a
WARN_ON about bytes_may_use.

Fixes: ("btrfs: update btrfs_space_info's bytes_may_use timely")
Signed-off-by: Wang Xiaoguang <wangxg.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-05 17:40:41 +02:00
Linus Torvalds
4b30b6d126 Merge branch 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "I'm still prepping a set of fixes for btrfs fsync, just nailing down a
  hard to trigger memory corruption.  For now, these are tested and ready."

* 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  btrfs: fix one bug that process may endlessly wait for ticket in wait_reserve_ticket()
  Btrfs: fix endless loop in balancing block groups
  Btrfs: kill invalid ASSERT() in process_all_refs()
2016-09-03 12:40:45 -07:00
Wang Xiaoguang
e0af24849e btrfs: fix one bug that process may endlessly wait for ticket in wait_reserve_ticket()
If can_overcommit() in btrfs_calc_reclaim_metadata_size() returns true,
btrfs_async_reclaim_metadata_space() will not reclaim metadata space, just
return directly and also forget to wake up process which are waiting for
their tickets, so these processes will wait endlessly.

Fstests case generic/172 with mount option "-o compress=lzo" have revealed
this bug in my test machine. Here if we have tickets to handle, we must
handle them first.

Signed-off-by: Wang Xiaoguang <wangxg.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-01 17:23:24 +02:00
Liu Bo
a9b1fc851d Btrfs: fix endless loop in balancing block groups
Qgroup function may overwrite the saved error 'err' with 0
in case quota is not enabled, and this ends up with a
endless loop in balance because we keep going back to balance
the same block group.

It really should use 'ret' instead.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-01 17:16:47 +02:00
Josef Bacik
3dc09ec895 Btrfs: kill invalid ASSERT() in process_all_refs()
Suppose you have the following tree in snap1 on a file system mounted with -o
inode_cache so that inode numbers are recycled

└── [    258]  a
    └── [    257]  b

and then you remove b, rename a to c, and then re-create b in c so you have the
following tree

└── [    258]  c
    └── [    257]  b

and then you try to do an incremental send you will hit

ASSERT(pending_move == 0);

in process_all_refs().  This is because we assume that any recycling of inodes
will not have a pending change in our path, which isn't the case.  This is the
case for the DELETE side, since we want to remove the old file using the old
path, but on the create side we could have a pending move and need to do the
normal pending rename dance.  So remove this ASSERT() and put a comment about
why we ignore pending_move.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-01 17:16:47 +02:00
Linus Torvalds
28687b935e Merge branch 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "We've queued up a few different fixes in here.  These range from
  enospc corners to fsync and quota fixes, and a few targeted at error
  handling for corrupt metadata/fuzzing"

* 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: fix lockdep warning on deadlock against an inode's log mutex
  Btrfs: detect corruption when non-root leaf has zero item
  Btrfs: check btree node's nritems
  btrfs: don't create or leak aliased root while cleaning up orphans
  Btrfs: fix em leak in find_first_block_group
  btrfs: do not background blkdev_put()
  Btrfs: clarify do_chunk_alloc()'s return value
  btrfs: fix fsfreeze hang caused by delayed iputs deal
  btrfs: update btrfs_space_info's bytes_may_use timely
  btrfs: divide btrfs_update_reserved_bytes() into two functions
  btrfs: use correct offset for reloc_inode in prealloc_file_extent_cluster()
  btrfs: qgroup: Fix qgroup incorrectness caused by log replay
  btrfs: relocation: Fix leaking qgroups numbers on data extents
  btrfs: qgroup: Refactor btrfs_qgroup_insert_dirty_extent()
  btrfs: waiting on qgroup rescan should not always be interruptible
  btrfs: properly track when rescan worker is running
  btrfs: flush_space: treat return value of do_chunk_alloc properly
  Btrfs: add ASSERT for block group's memory leak
  btrfs: backref: Fix soft lockup in __merge_refs function
  Btrfs: fix memory leak of reloc_root
2016-08-26 20:22:01 -07:00
Filipe Manana
28a235931b Btrfs: fix lockdep warning on deadlock against an inode's log mutex
Commit 44f714dae5 ("Btrfs: improve performance on fsync against new
inode after rename/unlink"), which landed in 4.8-rc2, introduced a
possibility for a deadlock due to double locking of an inode's log mutex
by the same task, which lockdep reports with:

[23045.433975] =============================================
[23045.434748] [ INFO: possible recursive locking detected ]
[23045.435426] 4.7.0-rc6-btrfs-next-34+ #1 Not tainted
[23045.436044] ---------------------------------------------
[23045.436044] xfs_io/3688 is trying to acquire lock:
[23045.436044]  (&ei->log_mutex){+.+...}, at: [<ffffffffa038552d>] btrfs_log_inode+0x13a/0xc95 [btrfs]
[23045.436044]
               but task is already holding lock:
[23045.436044]  (&ei->log_mutex){+.+...}, at: [<ffffffffa038552d>] btrfs_log_inode+0x13a/0xc95 [btrfs]
[23045.436044]
               other info that might help us debug this:
[23045.436044]  Possible unsafe locking scenario:

[23045.436044]        CPU0
[23045.436044]        ----
[23045.436044]   lock(&ei->log_mutex);
[23045.436044]   lock(&ei->log_mutex);
[23045.436044]
                *** DEADLOCK ***

[23045.436044]  May be due to missing lock nesting notation

[23045.436044] 3 locks held by xfs_io/3688:
[23045.436044]  #0:  (&sb->s_type->i_mutex_key#15){+.+...}, at: [<ffffffffa035f2ae>] btrfs_sync_file+0x14e/0x425 [btrfs]
[23045.436044]  #1:  (sb_internal#2){.+.+.+}, at: [<ffffffff8118446b>] __sb_start_write+0x5f/0xb0
[23045.436044]  #2:  (&ei->log_mutex){+.+...}, at: [<ffffffffa038552d>] btrfs_log_inode+0x13a/0xc95 [btrfs]
[23045.436044]
               stack backtrace:
[23045.436044] CPU: 4 PID: 3688 Comm: xfs_io Not tainted 4.7.0-rc6-btrfs-next-34+ #1
[23045.436044] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.1-0-gb3ef39f-prebuilt.qemu-project.org 04/01/2014
[23045.436044]  0000000000000000 ffff88022f5f7860 ffffffff8127074d ffffffff82a54b70
[23045.436044]  ffffffff82a54b70 ffff88022f5f7920 ffffffff81092897 ffff880228015d68
[23045.436044]  0000000000000000 ffffffff82a54b70 ffffffff829c3f00 ffff880228015d68
[23045.436044] Call Trace:
[23045.436044]  [<ffffffff8127074d>] dump_stack+0x67/0x90
[23045.436044]  [<ffffffff81092897>] __lock_acquire+0xcbb/0xe4e
[23045.436044]  [<ffffffff8109155f>] ? mark_lock+0x24/0x201
[23045.436044]  [<ffffffff8109179a>] ? mark_held_locks+0x5e/0x74
[23045.436044]  [<ffffffff81092de0>] lock_acquire+0x12f/0x1c3
[23045.436044]  [<ffffffff81092de0>] ? lock_acquire+0x12f/0x1c3
[23045.436044]  [<ffffffffa038552d>] ? btrfs_log_inode+0x13a/0xc95 [btrfs]
[23045.436044]  [<ffffffffa038552d>] ? btrfs_log_inode+0x13a/0xc95 [btrfs]
[23045.436044]  [<ffffffff814a51a4>] mutex_lock_nested+0x77/0x3a7
[23045.436044]  [<ffffffffa038552d>] ? btrfs_log_inode+0x13a/0xc95 [btrfs]
[23045.436044]  [<ffffffffa039705e>] ? btrfs_release_delayed_node+0xb/0xd [btrfs]
[23045.436044]  [<ffffffffa038552d>] btrfs_log_inode+0x13a/0xc95 [btrfs]
[23045.436044]  [<ffffffffa038552d>] ? btrfs_log_inode+0x13a/0xc95 [btrfs]
[23045.436044]  [<ffffffff810a0ed1>] ? vprintk_emit+0x453/0x465
[23045.436044]  [<ffffffffa0385a61>] btrfs_log_inode+0x66e/0xc95 [btrfs]
[23045.436044]  [<ffffffffa03c084d>] log_new_dir_dentries+0x26c/0x359 [btrfs]
[23045.436044]  [<ffffffffa03865aa>] btrfs_log_inode_parent+0x4a6/0x628 [btrfs]
[23045.436044]  [<ffffffffa0387552>] btrfs_log_dentry_safe+0x5a/0x75 [btrfs]
[23045.436044]  [<ffffffffa035f464>] btrfs_sync_file+0x304/0x425 [btrfs]
[23045.436044]  [<ffffffff811acaf4>] vfs_fsync_range+0x8c/0x9e
[23045.436044]  [<ffffffff811acb22>] vfs_fsync+0x1c/0x1e
[23045.436044]  [<ffffffff811acc79>] do_fsync+0x31/0x4a
[23045.436044]  [<ffffffff811ace99>] SyS_fsync+0x10/0x14
[23045.436044]  [<ffffffff814a88e5>] entry_SYSCALL_64_fastpath+0x18/0xa8
[23045.436044]  [<ffffffff8108f039>] ? trace_hardirqs_off_caller+0x3f/0xaa

An example reproducer for this is:

   $ mkfs.btrfs -f /dev/sdb
   $ mount /dev/sdb /mnt
   $ mkdir /mnt/dir
   $ touch /mnt/dir/foo
   $ sync
   $ mv /mnt/dir/foo /mnt/dir/bar
   $ touch /mnt/dir/foo
   $ xfs_io -c "fsync" /mnt/dir/bar

This is because while logging the inode of file bar we end up logging its
parent directory (since its inode has an unlink_trans field matching the
current transaction id due to the rename operation), which in turn logs
the inodes for all its new dentries, so that the new inode for the new
file named foo gets logged which in turn triggered another logging attempt
for the inode we are fsync'ing, since that inode had an old name that
corresponds to the name of the new inode.

So fix this by ensuring that when logging the inode for a new dentry that
has a name matching an old name of some other inode, we don't log again
the original inode that we are fsync'ing.

Fixes: 44f714dae5 ("Btrfs: improve performance on fsync against new inode after rename/unlink")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2016-08-25 03:58:32 -07:00
Liu Bo
1ba98d086f Btrfs: detect corruption when non-root leaf has zero item
Right now we treat leaf which has zero item as a valid one
because we could have an empty tree, that is, a root that is
also a leaf without any item, however, in the same case but
when the leaf is not a root, we can end up with hitting the
BUG_ON(1) in btrfs_extend_item() called by
setup_inline_extent_backref().

This makes us check the situation as a corruption if leaf is
not its own root.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2016-08-25 03:58:31 -07:00
Liu Bo
053ab70f06 Btrfs: check btree node's nritems
When btree node (level = 1) has nritems which equals to zero,
we can end up with panic due to insert_ptr()'s

BUG_ON(slot > nritems);

where slot is 1 and nritems is 0, as copy_for_split() calls
insert_ptr(.., path->slots[1] + 1, ...);

A invalid value results in the whole mess, this adds the check
for btree's node nritems so that we stop reading block when
when something is wrong.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2016-08-25 03:58:30 -07:00
Jeff Mahoney
35bbb97fc8 btrfs: don't create or leak aliased root while cleaning up orphans
commit 909c3a22da (Btrfs: fix loading of orphan roots leading to BUG_ON)
avoids the BUG_ON but can add an aliased root to the dead_roots list or
leak the root.

Since we've already been loading roots into the radix tree, we should
use it before looking the root up on disk.

Cc: <stable@vger.kernel.org> # 4.5
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2016-08-25 03:58:29 -07:00
Josef Bacik
187ee58c62 Btrfs: fix em leak in find_first_block_group
We need to call free_extent_map() on the em we look up.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2016-08-25 03:58:29 -07:00
Anand Jain
1423881941 btrfs: do not background blkdev_put()
At the end of unmount/dev-delete, if the device exclusive open is not
actually closed, then there might be a race with another program in
the userland who is trying to open the device in exclusive mode and
it may fail for eg:
      unmount /btrfs; fsck /dev/x
      btrfs dev del /dev/x /btrfs; fsck /dev/x
so here background blkdev_put() is not a choice

Signed-off-by: Anand Jain <Anand.Jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2016-08-25 03:58:28 -07:00
Liu Bo
28b737f6ed Btrfs: clarify do_chunk_alloc()'s return value
Function start_transaction() can return ERR_PTR(1) when flush is
BTRFS_RESERVE_FLUSH_LIMIT, so the call graph is

start_transaction (return ERR_PTR(1))
  -> btrfs_block_rsv_add (return 1)
     -> reserve_metadata_bytes (return 1)
        -> flush_space (return 1)
           -> do_chunk_alloc  (return 1)

With BTRFS_RESERVE_FLUSH_LIMIT, if flush_space is already on the
flush_state of ALLOC_CHUNK and it successfully allocates a new
chunk, then instead of trying to reserve space again,
reserve_metadata_bytes returns 1 immediately.

Eventually the callers who call start_transaction() usually just
do the IS_ERR() check which ERR_PTR(1) can pass, then it'll get
a panic when dereferencing a pointer which is ERR_PTR(1).

The following patch fixes the above problem.
"btrfs: flush_space: treat return value of do_chunk_alloc properly"
https://patchwork.kernel.org/patch/7778651/

This add comments to clarify do_chunk_alloc()'s return value.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2016-08-25 03:58:27 -07:00
Wang Xiaoguang
9e7cc91a6d btrfs: fix fsfreeze hang caused by delayed iputs deal
When running fstests generic/068, sometimes we got below deadlock:
  xfs_io          D ffff8800331dbb20     0  6697   6693 0x00000080
  ffff8800331dbb20 ffff88007acfc140 ffff880034d895c0 ffff8800331dc000
  ffff880032d243e8 fffffffeffffffff ffff880032d24400 0000000000000001
  ffff8800331dbb38 ffffffff816a9045 ffff880034d895c0 ffff8800331dbba8
  Call Trace:
  [<ffffffff816a9045>] schedule+0x35/0x80
  [<ffffffff816abab2>] rwsem_down_read_failed+0xf2/0x140
  [<ffffffff8118f5e1>] ? __filemap_fdatawrite_range+0xd1/0x100
  [<ffffffff8134f978>] call_rwsem_down_read_failed+0x18/0x30
  [<ffffffffa06631fc>] ? btrfs_alloc_block_rsv+0x2c/0xb0 [btrfs]
  [<ffffffff810d32b5>] percpu_down_read+0x35/0x50
  [<ffffffff81217dfc>] __sb_start_write+0x2c/0x40
  [<ffffffffa067f5d5>] start_transaction+0x2a5/0x4d0 [btrfs]
  [<ffffffffa067f857>] btrfs_join_transaction+0x17/0x20 [btrfs]
  [<ffffffffa068ba34>] btrfs_evict_inode+0x3c4/0x5d0 [btrfs]
  [<ffffffff81230a1a>] evict+0xba/0x1a0
  [<ffffffff812316b6>] iput+0x196/0x200
  [<ffffffffa06851d0>] btrfs_run_delayed_iputs+0x70/0xc0 [btrfs]
  [<ffffffffa067f1d8>] btrfs_commit_transaction+0x928/0xa80 [btrfs]
  [<ffffffffa0646df0>] btrfs_freeze+0x30/0x40 [btrfs]
  [<ffffffff81218040>] freeze_super+0xf0/0x190
  [<ffffffff81229275>] do_vfs_ioctl+0x4a5/0x5c0
  [<ffffffff81003176>] ? do_audit_syscall_entry+0x66/0x70
  [<ffffffff810038cf>] ? syscall_trace_enter_phase1+0x11f/0x140
  [<ffffffff81229409>] SyS_ioctl+0x79/0x90
  [<ffffffff81003c12>] do_syscall_64+0x62/0x110
  [<ffffffff816acbe1>] entry_SYSCALL64_slow_path+0x25/0x25

>From this warning, freeze_super() already holds SB_FREEZE_FS, but
btrfs_freeze() will call btrfs_commit_transaction() again, if
btrfs_commit_transaction() finds that it has delayed iputs to handle,
it'll start_transaction(), which will try to get SB_FREEZE_FS lock
again, then deadlock occurs.

The root cause is that in btrfs, sync_filesystem(sb) does not make
sure all metadata is updated. There still maybe some codes adding
delayed iputs, see below sample race window:

         CPU1                                  |         CPU2
|-> freeze_super()                             |
    |-> sync_filesystem(sb);                   |
    |                                          |-> cleaner_kthread()
    |                                          |   |-> btrfs_delete_unused_bgs()
    |                                          |       |-> btrfs_remove_chunk()
    |                                          |           |-> btrfs_remove_block_group()
    |                                          |               |-> btrfs_add_delayed_iput()
    |                                          |
    |-> sb->s_writers.frozen = SB_FREEZE_FS;   |
    |-> sb_wait_write(sb, SB_FREEZE_FS);       |
    |   acquire SB_FREEZE_FS lock.             |
    |                                          |
    |-> btrfs_freeze()                         |
        |-> btrfs_commit_transaction()         |
            |-> btrfs_run_delayed_iputs()      |
            |   will handle delayed iputs,     |
            |   that means start_transaction() |
            |   will be called, which will try |
            |   to get SB_FREEZE_FS lock.      |

To fix this issue, introduce a "int fs_frozen" to record internally whether
fs has been frozen. If fs has been frozen, we can not handle delayed iputs.

Signed-off-by: Wang Xiaoguang <wangxg.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add comment to btrfs_freeze ]
Signed-off-by: David Sterba <dsterba@suse.com>

Signed-off-by: Chris Mason <clm@fb.com>
2016-08-25 03:58:26 -07:00
Wang Xiaoguang
18513091af btrfs: update btrfs_space_info's bytes_may_use timely
This patch can fix some false ENOSPC errors, below test script can
reproduce one false ENOSPC error:
	#!/bin/bash
	dd if=/dev/zero of=fs.img bs=$((1024*1024)) count=128
	dev=$(losetup --show -f fs.img)
	mkfs.btrfs -f -M $dev
	mkdir /tmp/mntpoint
	mount $dev /tmp/mntpoint
	cd /tmp/mntpoint
	xfs_io -f -c "falloc 0 $((64*1024*1024))" testfile

Above script will fail for ENOSPC reason, but indeed fs still has free
space to satisfy this request. Please see call graph:
btrfs_fallocate()
|-> btrfs_alloc_data_chunk_ondemand()
|   bytes_may_use += 64M
|-> btrfs_prealloc_file_range()
    |-> btrfs_reserve_extent()
        |-> btrfs_add_reserved_bytes()
        |   alloc_type is RESERVE_ALLOC_NO_ACCOUNT, so it does not
        |   change bytes_may_use, and bytes_reserved += 64M. Now
        |   bytes_may_use + bytes_reserved == 128M, which is greater
        |   than btrfs_space_info's total_bytes, false enospc occurs.
        |   Note, the bytes_may_use decrease operation will be done in
        |   end of btrfs_fallocate(), which is too late.

Here is another simple case for buffered write:
                    CPU 1              |              CPU 2
                                       |
|-> cow_file_range()                   |-> __btrfs_buffered_write()
    |-> btrfs_reserve_extent()         |   |
    |                                  |   |
    |                                  |   |
    |    .....                         |   |-> btrfs_check_data_free_space()
    |                                  |
    |                                  |
    |-> extent_clear_unlock_delalloc() |

In CPU 1, btrfs_reserve_extent()->find_free_extent()->
btrfs_add_reserved_bytes() do not decrease bytes_may_use, the decrease
operation will be delayed to be done in extent_clear_unlock_delalloc().
Assume in this case, btrfs_reserve_extent() reserved 128MB data, CPU2's
btrfs_check_data_free_space() tries to reserve 100MB data space.
If
	100MB > data_sinfo->total_bytes - data_sinfo->bytes_used -
		data_sinfo->bytes_reserved - data_sinfo->bytes_pinned -
		data_sinfo->bytes_readonly - data_sinfo->bytes_may_use
btrfs_check_data_free_space() will try to allcate new data chunk or call
btrfs_start_delalloc_roots(), or commit current transaction in order to
reserve some free space, obviously a lot of work. But indeed it's not
necessary as long as decreasing bytes_may_use timely, we still have
free space, decreasing 128M from bytes_may_use.

To fix this issue, this patch chooses to update bytes_may_use for both
data and metadata in btrfs_add_reserved_bytes(). For compress path, real
extent length may not be equal to file content length, so introduce a
ram_bytes argument for btrfs_reserve_extent(), find_free_extent() and
btrfs_add_reserved_bytes(), it's becasue bytes_may_use is increased by
file content length. Then compress path can update bytes_may_use
correctly. Also now we can discard RESERVE_ALLOC_NO_ACCOUNT, RESERVE_ALLOC
and RESERVE_FREE.

As we know, usually EXTENT_DO_ACCOUNTING is used for error path. In
run_delalloc_nocow(), for inode marked as NODATACOW or extent marked as
PREALLOC, we also need to update bytes_may_use, but can not pass
EXTENT_DO_ACCOUNTING, because it also clears metadata reservation, so
here we introduce EXTENT_CLEAR_DATA_RESV flag to indicate btrfs_clear_bit_hook()
to update btrfs_space_info's bytes_may_use.

Meanwhile __btrfs_prealloc_file_range() will call
btrfs_free_reserved_data_space() internally for both sucessful and failed
path, btrfs_prealloc_file_range()'s callers does not need to call
btrfs_free_reserved_data_space() any more.

Signed-off-by: Wang Xiaoguang <wangxg.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2016-08-25 03:58:26 -07:00
Wang Xiaoguang
4824f1f412 btrfs: divide btrfs_update_reserved_bytes() into two functions
This patch divides btrfs_update_reserved_bytes() into
btrfs_add_reserved_bytes() and btrfs_free_reserved_bytes(), and
next patch will extend btrfs_add_reserved_bytes()to fix some
false ENOSPC error, please see later patch for detailed info.

Signed-off-by: Wang Xiaoguang <wangxg.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2016-08-25 03:58:25 -07:00
Wang Xiaoguang
dcb40c196f btrfs: use correct offset for reloc_inode in prealloc_file_extent_cluster()
In prealloc_file_extent_cluster(), btrfs_check_data_free_space() uses
wrong file offset for reloc_inode, it uses cluster->start and cluster->end,
which indeed are extent's bytenr. The correct value should be
cluster->[start|end] minus block group's start bytenr.

start bytenr   cluster->start
|              |     extent      |   extent   | ...| extent |
|----------------------------------------------------------------|
|                block group reloc_inode                         |

Signed-off-by: Wang Xiaoguang <wangxg.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2016-08-25 03:58:24 -07:00
Qu Wenruo
df2c95f33e btrfs: qgroup: Fix qgroup incorrectness caused by log replay
When doing log replay at mount time(after power loss), qgroup will leak
numbers of replayed data extents.

The cause is almost the same of balance.
So fix it by manually informing qgroup for owner changed extents.

The bug can be detected by btrfs/119 test case.

Cc: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-and-Tested-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2016-08-25 03:58:23 -07:00
Qu Wenruo
62b99540a1 btrfs: relocation: Fix leaking qgroups numbers on data extents
This patch fixes a REGRESSION introduced in 4.2, caused by the big quota
rework.

When balancing data extents, qgroup will leak all its numbers for
relocated data extents.

The relocation is done in the following steps for data extents:
1) Create data reloc tree and inode
2) Copy all data extents to data reloc tree
   And commit transaction
3) Create tree reloc tree(special snapshot) for any related subvolumes
4) Replace file extent in tree reloc tree with new extents in data reloc
   tree
   And commit transaction
5) Merge tree reloc tree with original fs, by swapping tree blocks

For 1)~4), since tree reloc tree and data reloc tree doesn't count to
qgroup, everything is OK.

But for 5), the swapping of tree blocks will only info qgroup to track
metadata extents.

If metadata extents contain file extents, qgroup number for file extents
will get lost, leading to corrupted qgroup accounting.

The fix is, before commit transaction of step 5), manually info qgroup to
track all file extents in data reloc tree.
Since at commit transaction time, the tree swapping is done, and qgroup
will account these data extents correctly.

Cc: Mark Fasheh <mfasheh@suse.de>
Reported-by: Mark Fasheh <mfasheh@suse.de>
Reported-by: Filipe Manana <fdmanana@gmail.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2016-08-25 03:58:22 -07:00
Qu Wenruo
cb93b52cc0 btrfs: qgroup: Refactor btrfs_qgroup_insert_dirty_extent()
Refactor btrfs_qgroup_insert_dirty_extent() function, to two functions:
1. btrfs_qgroup_insert_dirty_extent_nolock()
   Almost the same with original code.
   For delayed_ref usage, which has delayed refs locked.

   Change the return value type to int, since caller never needs the
   pointer, but only needs to know if they need to free the allocated
   memory.

2. btrfs_qgroup_insert_dirty_extent()
   The more encapsulated version.

   Will do the delayed_refs lock, memory allocation, quota enabled check
   and other things.

The original design is to keep exported functions to minimal, but since
more btrfs hacks exposed, like replacing path in balance, we need to
record dirty extents manually, so we have to add such functions.

Also, add comment for both functions, to info developers how to keep
qgroup correct when doing hacks.

Cc: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-and-Tested-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2016-08-25 03:58:21 -07:00
Jeff Mahoney
d06f23d6a9 btrfs: waiting on qgroup rescan should not always be interruptible
We wait on qgroup rescan completion in three places: file system
shutdown, the quota disable ioctl, and the rescan wait ioctl.  If the
user sends a signal while we're waiting, we continue happily along.  This
is expected behavior for the rescan wait ioctl.  It's racy in the shutdown
path but mostly works due to other unrelated synchronization points.
In the quota disable path, it Oopses the kernel pretty much immediately.

Cc: <stable@vger.kernel.org> # v4.4+
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2016-08-25 03:58:20 -07:00
Jeff Mahoney
d2c609b834 btrfs: properly track when rescan worker is running
The qgroup_flags field is overloaded such that it reflects the on-disk
status of qgroups and the runtime state.  The BTRFS_QGROUP_STATUS_FLAG_RESCAN
flag is used to indicate that a rescan operation is in progress, but if
the file system is unmounted while a rescan is running, the rescan
operation is paused.  If the file system is then mounted read-only,
the flag will still be present but the rescan operation will not have
been resumed.  When we go to umount, btrfs_qgroup_wait_for_completion
will see the flag and interpret it to mean that the rescan worker is
still running and will wait for a completion that will never come.

This patch uses a separate flag to indicate when the worker is
running.  The locking and state surrounding the qgroup rescan worker
needs a lot of attention beyond this patch but this is enough to
avoid a hung umount.

Cc: <stable@vger.kernel.org> # v4.4+
Signed-off-by; Jeff Mahoney <jeffm@suse.com>
Reviewed-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>

Signed-off-by: Chris Mason <clm@fb.com>
2016-08-25 03:58:19 -07:00
Alex Lyakas
eecba891d3 btrfs: flush_space: treat return value of do_chunk_alloc properly
do_chunk_alloc returns 1 when it succeeds to allocate a new chunk.
But flush_space will not convert this to 0, and will also return 1.
As a result, reserve_metadata_bytes will think that flush_space failed,
and may potentially return this value "1" to the caller (depends how
reserve_metadata_bytes was called). The caller will also treat this as an error.
For example, btrfs_block_rsv_refill does:

int ret = -ENOSPC;
...
ret = reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
if (!ret) {
        block_rsv_add_bytes(block_rsv, num_bytes, 0);
        return 0;
}

return ret;

So it will return -ENOSPC.

Signed-off-by: Alex Lyakas <alex@zadarastorage.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2016-08-25 03:58:18 -07:00
Liu Bo
f3bca8028b Btrfs: add ASSERT for block group's memory leak
This adds several ASSERT()' s to report memory leak of block group cache.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2016-08-25 03:58:17 -07:00
Qu Wenruo
d8422ba334 btrfs: backref: Fix soft lockup in __merge_refs function
When over 1000 file extents refers to one extent, find_parent_nodes()
will be obviously slow, due to the O(n^2)~O(n^3) loops inside
__merge_refs().

The following ftrace shows the cubic growth of execution time:

256 refs
 5) + 91.768 us   |  __add_keyed_refs.isra.12 [btrfs]();
 5)   1.447 us    |  __add_missing_keys.isra.13 [btrfs]();
 5) ! 114.544 us  |  __merge_refs [btrfs]();
 5) ! 136.399 us  |  __merge_refs [btrfs]();

512 refs
 6) ! 279.859 us  |  __add_keyed_refs.isra.12 [btrfs]();
 6)   3.164 us    |  __add_missing_keys.isra.13 [btrfs]();
 6) ! 442.498 us  |  __merge_refs [btrfs]();
 6) # 2091.073 us |  __merge_refs [btrfs]();

and 1024 refs
 7) ! 368.683 us  |  __add_keyed_refs.isra.12 [btrfs]();
 7)   4.810 us    |  __add_missing_keys.isra.13 [btrfs]();
 7) # 2043.428 us |  __merge_refs [btrfs]();
 7) * 18964.23 us |  __merge_refs [btrfs]();

And sort them into the following char:
(Unit: us)
------------------------------------------------------------------------
 Trace function        | 256 ref        | 512 refs      | 1024 refs    |
------------------------------------------------------------------------
 __add_keyed_refs      | 91             | 249           | 368          |
 __add_missing_keys    | 1              | 3             | 4            |
 __merge_refs 1st call | 114            | 442           | 2043         |
 __merge_refs 2nd call | 136            | 2091          | 18964        |
------------------------------------------------------------------------

We can see the that __add_keyed_refs() grows almost in linear behavior.
And __add_missing_keys() in this case doesn't change much or takes much
time.

While for the 1st __merge_refs() it's square growth
for the 2nd __merge_refs() call it's cubic growth.

It's no doubt that merge_refs() will take a long long time to execute if
the number of refs continues its grows.

So add a cond_resced() into the loop of __merge_refs().

Although this will solve the problem of soft lockup, we need to use the
new rb_tree based structure introduced by Lu Fengqi to really solve the
long execution time.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2016-08-25 03:58:16 -07:00
Liu Bo
1c1ea4f781 Btrfs: fix memory leak of reloc_root
When some critical errors occur and FS would be flipped into RO,
if we have an on-going balance, we can end up with a memory leak
of root->reloc_root since btrfs_drop_snapshots() bails out
without freeing reloc_root at the very early start.

However, we're not able to free reloc_root in btrfs_drop_snapshots()
because its caller, merge_reloc_roots(), still needs to access it to
cleanup reloc_root's rbtree.

This makes us free reloc_root when we're going to free fs/file roots.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2016-08-25 03:58:15 -07:00
Linus Torvalds
9512c47ec2 Merge branch 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "Some fixes for btrfs send/recv and fsync from Filipe and Robbie Ko.

  Bonus points to Filipe for already having xfstests in place for many
  of these"

* 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: remove unused function btrfs_add_delayed_qgroup_reserve()
  Btrfs: improve performance on fsync against new inode after rename/unlink
  Btrfs: be more precise on errors when getting an inode from disk
  Btrfs: send, don't bug on inconsistent snapshots
  Btrfs: send, avoid incorrect leaf accesses when sending utimes operations
  Btrfs: send, fix invalid leaf accesses due to incorrect utimes operations
  Btrfs: send, fix warning due to late freeing of orphan_dir_info structures
  Btrfs: incremental send, fix premature rmdir operations
  Btrfs: incremental send, fix invalid paths for rename operations
  Btrfs: send, add missing error check for calls to path_loop()
  Btrfs: send, fix failure to move directories with the same name around
  Btrfs: add missing check for writeback errors on fsync
2016-08-10 11:16:03 -07:00
Jens Axboe
1eff9d322a block: rename bio bi_rw to bi_opf
Since commit 63a4cc2486, bio->bi_rw contains flags in the lower
portion and the op code in the higher portions. This means that
old code that relies on manually setting bi_rw is most likely
going to be broken. Instead of letting that brokeness linger,
rename the member, to force old and out-of-tree code to break
at compile time instead of at runtime.

No intended functional changes in this commit.

Signed-off-by: Jens Axboe <axboe@fb.com>
2016-08-07 14:41:02 -06:00
Linus Torvalds
fff648da96 Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
 "Here's the second round of block updates for this merge window.

  It's a mix of fixes for changes that went in previously in this round,
  and fixes in general.  This pull request contains:

   - Fixes for loop from Christoph

   - A bdi vs gendisk lifetime fix from Dan, worth two cookies.

   - A blk-mq timeout fix, when on frozen queues.  From Gabriel.

   - Writeback fix from Jan, ensuring that __writeback_single_inode()
     does the right thing.

   - Fix for bio->bi_rw usage in f2fs from me.

   - Error path deadlock fix in blk-mq sysfs registration from me.

   - Floppy O_ACCMODE fix from Jiri.

   - Fix to the new bio op methods from Mike.

     One more followup will be coming here, ensuring that we don't
     propagate the block types outside of block.  That, and a rename of
     bio->bi_rw is coming right after -rc1 is cut.

   - Various little fixes"

* 'for-linus' of git://git.kernel.dk/linux-block:
  mm/block: convert rw_page users to bio op use
  loop: make do_req_filebacked more robust
  loop: don't try to use AIO for discards
  blk-mq: fix deadlock in blk_mq_register_disk() error path
  Include: blkdev: Removed duplicate 'struct request;' declaration.
  Fixup direct bi_rw modifiers
  block: fix bdi vs gendisk lifetime mismatch
  blk-mq: Allow timeouts to run while queue is freezing
  nbd: fix race in ioctl
  block: fix use-after-free in seq file
  f2fs: drop bio->bi_rw manual assignment
  block: add missing group association in bio-cloning functions
  blkcg: kill unused field nr_undestroyed_grps
  writeback: Write dirty times for WB_SYNC_ALL writeback
  floppy: fix open(O_ACCMODE) for ioctl-only open
2016-08-05 23:31:51 -04:00
Chris Mason
1083881654 Merge branch 'integration-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/fdmanana/linux into for-linus-4.8 2016-08-05 12:25:05 -07:00
Linus Torvalds
d58b0d980f Merge branch 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull more btrfs updates from Chris Mason:
 "This is part two of my btrfs pull, which is some cleanups and a batch
  of fixes.

  Most of the code here is from Jeff Mahoney, making the pointers we
  pass around internally more consistent and less confusing overall.  I
  noticed a small problem right before I sent this out yesterday, so I
  fixed it up and re-tested overnight"

* 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (40 commits)
  Btrfs: fix __MAX_CSUM_ITEMS
  btrfs: btrfs_abort_transaction, drop root parameter
  btrfs: add btrfs_trans_handle->fs_info pointer
  btrfs: btrfs_relocate_chunk pass extent_root to btrfs_end_transaction
  btrfs: convert nodesize macros to static inlines
  btrfs: introduce BTRFS_MAX_ITEM_SIZE
  btrfs: cleanup, remove prototype for btrfs_find_root_ref
  btrfs: copy_to_sk drop unused root parameter
  btrfs: simpilify btrfs_subvol_inherit_props
  btrfs: tests, use BTRFS_FS_STATE_DUMMY_FS_INFO instead of dummy root
  btrfs: tests, require fs_info for root
  btrfs: tests, move initialization into tests/
  btrfs: btrfs_test_opt and friends should take a btrfs_fs_info
  btrfs: prefix fsid to all trace events
  btrfs: plumb fs_info into btrfs_work
  btrfs: remove obsolete part of comment in statfs
  btrfs: hide test-only member under ifdef
  btrfs: Ratelimit "no csum found" info message
  btrfs: Add ratelimit to btrfs printing
  Btrfs: fix unexpected balance crash due to BUG_ON
  ...
2016-08-04 19:56:16 -04:00
Shaun Tancheff
b571bc606e Fixup direct bi_rw modifiers
bi_rw should be using bio_set_op_attrs to set bi_rw.

Signed-off-by: Shaun Tancheff <shaun@tancheff.com>
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: David Sterba <dsterba@suse.com>
Cc: Mike Christie <mchristi@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-08-04 14:19:16 -06:00
Paolo Valente
20bd723ec6 block: add missing group association in bio-cloning functions
When a bio is cloned, the newly created bio must be associated with
the same blkcg as the original bio (if BLK_CGROUP is enabled). If
this operation is not performed, then the new bio is not associated
with any group, and the group of the current task is returned when
the group of the bio is requested.

Depending on the cloning frequency, this may cause a large
percentage of the bios belonging to a given group to be treated
as if belonging to other groups (in most cases as if belonging to
the root group). The expected group isolation may thereby be broken.

This commit adds the missing association in bio-cloning functions.

Fixes: da2f0f74cf ("Btrfs: add support for blkio controllers")
Cc: stable@vger.kernel.org # v4.3+

Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Reviewed-by: Nikolay Borisov <kernel@kyup.com>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-08-04 14:19:16 -06:00
Chris Mason
42049bf60d Btrfs: fix __MAX_CSUM_ITEMS
Jeff Mahoney's cleanup commit (14a1e067b4) wasn't correct for csums on
machines where the pagesize >= metadata blocksize.

This just reverts the relevant hunks to bring the old math back.

Signed-off-by: Chris Mason <clm@fb.com>
2016-08-03 14:08:37 -07:00
Filipe Manana
e657149933 Btrfs: remove unused function btrfs_add_delayed_qgroup_reserve()
No longer used as of commit 5846a3c268 ("btrfs: qgroup: Fix a race in
delayed_ref which leads to abort trans").

Signed-off-by: Filipe Manana <fdmanana@suse.com>
2016-08-03 11:02:51 +01:00
Filipe Manana
44f714dae5 Btrfs: improve performance on fsync against new inode after rename/unlink
With commit 56f23fdbb6 ("Btrfs: fix file/data loss caused by fsync after
rename and new inode") we got simple fix for a functional issue when the
following sequence of actions is done:

  at transaction N
  create file A at directory D
  at transaction N + M (where M >= 1)
  move/rename existing file A from directory D to directory E
  create a new file named A at directory D
  fsync the new file
  power fail

The solution was to simply detect such scenario and fallback to a full
transaction commit when we detect it. However this turned out to had a
significant impact on throughput (and a bit on latency too) for benchmarks
using the dbench tool, which simulates real workloads from smbd (Samba)
servers. For example on a test vm (with a debug kernel):

Unpatched:
Throughput 19.1572 MB/sec  32 clients  32 procs  max_latency=1005.229 ms

Patched:
Throughput 23.7015 MB/sec  32 clients  32 procs  max_latency=809.206 ms

The patched results (this patch is applied) are similar to the results of
a kernel with the commit 56f23fdbb6 ("Btrfs: fix file/data loss caused
by fsync after rename and new inode") reverted.

This change avoids the fallback to a transaction commit and instead makes
sure all the names of the conflicting inode (the one that had a name in a
past transaction that matches the name of the new file in the same parent
directory) are logged so that at log replay time we don't lose neither the
new file nor the old file, and the old file gets the name it was renamed
to.

This also ends up avoiding a full transaction commit for a similar case
that involves an unlink instead of a rename of the old file:

  at transaction N
  create file A at directory D
  at transaction N + M (where M >= 1)
  remove file A
  create a new file named A at directory D
  fsync the new file
  power fail

Signed-off-by: Filipe Manana <fdmanana@suse.com>
2016-08-01 07:32:14 +01:00
Filipe Manana
67710892ec Btrfs: be more precise on errors when getting an inode from disk
When we attempt to read an inode from disk, we end up always returning an
-ESTALE error to the caller regardless of the actual failure reason, which
can be an out of memory problem (when allocating a path), some error found
when reading from the fs/subvolume btree (like a genuine IO error) or the
inode does not exists. So lets start returning the real error code to the
callers so that they don't treat all -ESTALE errors as meaning that the
inode does not exists (such as during orphan cleanup). This will also be
needed for a subsequent patch in the same series dealing with a special
fsync case.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
2016-08-01 07:32:03 +01:00
Filipe Manana
951555856b Btrfs: send, don't bug on inconsistent snapshots
When doing an incremental send, if we find a new/modified/deleted extent,
reference or xattr without having previously processed the corresponding
inode item we end up exexuting a BUG_ON(). This is because whenever an
extent, xattr or reference is added, modified or deleted, we always expect
to have the corresponding inode item updated. However there are situations
where this will not happen due to transient -ENOMEM or -ENOSPC errors when
doing delayed inode updates.

For example, when punching holes we can succeed in deleting and modifying
(shrinking) extents but later fail to do the delayed inode update. So after
such failure we close our transaction handle and right after a snapshot of
the fs/subvol tree can be made and used later for a send operation. The
same thing can happen during truncate, link, unlink, and xattr related
operations.

So instead of executing a BUG_ON, make send return an -EIO error and print
an informative error message do dmesg/syslog.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
2016-08-01 07:31:41 +01:00
Filipe Manana
15b253eace Btrfs: send, avoid incorrect leaf accesses when sending utimes operations
The caller of send_utimes() is supposed to be sure that the inode number
it passes to this function does actually exists in the send snapshot.
However due to logic/algorithm bugs (such as the one fixed by the patch
titled "Btrfs: send, fix invalid leaf accesses due to incorrect utimes
operations"), this might not be the case and when that happens it makes
send_utimes() access use an unrelated leaf item as the target inode item
or access beyond a leaf's boundaries (when the leaf is full and
path->slots[0] matches the number of items in the leaf).

So if the call to btrfs_search_slot() done by send_utimes() does not find
the inode item, just make sure send_utimes() returns -ENOENT and does not
silently accesses unrelated leaf items or does invalid leaf accesses, also
allowing us to easialy and deterministically catch such algorithmic/logic
bugs.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
2016-08-01 07:26:15 +01:00
Robbie Ko
764433a12e Btrfs: send, fix invalid leaf accesses due to incorrect utimes operations
During an incremental send, if we have delayed rename operations for inodes
that were children of directories which were removed in the send snapshot,
we can end up accessing incorrect items in a leaf or accessing beyond the
last item of the leaf due to issuing utimes operations for the removed
inodes. Consider the following example:

  Parent snapshot:
  .                                                             (ino 256)
  |--- a/                                                       (ino 257)
  |    |--- c/                                                  (ino 262)
  |
  |--- b/                                                       (ino 258)
  |    |--- d/                                                  (ino 263)
  |
  |--- del/                                                     (ino 261)
        |--- x/                                                 (ino 259)
        |--- y/                                                 (ino 260)

  Send snapshot:

  .                                                             (ino 256)
  |--- a/                                                       (ino 257)
  |
  |--- b/                                                       (ino 258)
  |
  |--- c/                                                       (ino 262)
  |    |--- y/                                                  (ino 260)
  |
  |--- d/                                                       (ino 263)
       |--- x/                                                  (ino 259)

1) When processing inodes 259 and 260, we end up delaying their rename
   operations because their parents, inodes 263 and 262 respectively, were
   not yet processed and therefore not yet renamed;

2) When processing inode 262, its rename operation is issued and right
   after the rename operation for inode 260 is issued. However right after
   issuing the rename operation for inode 260, at send.c:apply_dir_move(),
   we issue utimes operations for all current and past parents of inode
   260. This means we try to send a utimes operation for its old parent,
   inode 261 (deleted in the send snapshot), which does not cause any
   immediate and deterministic failure, because when the target inode is
   not found in the send snapshot, the send.c:send_utimes() function
   ignores it and uses the leaf region pointed to by path->slots[0],
   which can be any unrelated item (belonging to other inode) or it can
   be a region outside the leaf boundaries, if the leaf is full and
   path->slots[0] matches the number of items in the leaf. So we end
   up either successfully sending a utimes operation, which is fine
   and irrelevant because the old parent (inode 261) will end up being
   deleted later, or we end up doing an invalid memory access tha
   crashes the kernel.

So fix this by making apply_dir_move() issue utimes operations only for
parents that still exist in the send snapshot. In a separate patch we
will make send_utimes() return an error (-ENOENT) if the given inode
does not exists in the send snapshot.

Signed-off-by: Robbie Ko <robbieko@synology.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
[Rewrote change log to be more detailed and better organized]

Signed-off-by: Filipe Manana <fdmanana@suse.com>
2016-08-01 07:25:48 +01:00
Robbie Ko
443f9d266c Btrfs: send, fix warning due to late freeing of orphan_dir_info structures
Under certain situations, when doing an incremental send, we can end up
not freeing orphan_dir_info structures as soon as they are no longer
needed. Instead we end up freeing them only after finishing the send
stream, which causes a warning to be emitted:

[282735.229200] ------------[ cut here ]------------
[282735.229968] WARNING: CPU: 9 PID: 10588 at fs/btrfs/send.c:6298 btrfs_ioctl_send+0xe2f/0xe51 [btrfs]
[282735.231282] Modules linked in: btrfs crc32c_generic xor raid6_pq acpi_cpufreq tpm_tis ppdev tpm parport_pc psmouse parport sg pcspkr i2c_piix4 i2c_core evdev processor serio_raw button loop autofs4 ext4 crc16 jbd2 mbcache sr_mod cdrom sd_mod ata_generic virtio_scsi ata_piix libata virtio_pci virtio_ring virtio e1000 scsi_mod floppy [last unloaded: btrfs]
[282735.237130] CPU: 9 PID: 10588 Comm: btrfs Tainted: G        W       4.6.0-rc7-btrfs-next-31+ #1
[282735.239309] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014
[282735.240160]  0000000000000000 ffff880224273ca8 ffffffff8126b42c 0000000000000000
[282735.240160]  0000000000000000 ffff880224273ce8 ffffffff81052b14 0000189a24273ac8
[282735.240160]  ffff8802210c9800 0000000000000000 0000000000000001 0000000000000000
[282735.240160] Call Trace:
[282735.240160]  [<ffffffff8126b42c>] dump_stack+0x67/0x90
[282735.240160]  [<ffffffff81052b14>] __warn+0xc2/0xdd
[282735.240160]  [<ffffffff81052beb>] warn_slowpath_null+0x1d/0x1f
[282735.240160]  [<ffffffffa03c99d5>] btrfs_ioctl_send+0xe2f/0xe51 [btrfs]
[282735.240160]  [<ffffffffa0398358>] btrfs_ioctl+0x14f/0x1f81 [btrfs]
[282735.240160]  [<ffffffff8108e456>] ? arch_local_irq_save+0x9/0xc
[282735.240160]  [<ffffffff8118da05>] vfs_ioctl+0x18/0x34
[282735.240160]  [<ffffffff8118e00c>] do_vfs_ioctl+0x550/0x5be
[282735.240160]  [<ffffffff81196f0c>] ? __fget+0x6b/0x77
[282735.240160]  [<ffffffff81196fa1>] ? __fget_light+0x62/0x71
[282735.240160]  [<ffffffff8118e0d1>] SyS_ioctl+0x57/0x79
[282735.240160]  [<ffffffff8149e025>] entry_SYSCALL_64_fastpath+0x18/0xa8
[282735.240160]  [<ffffffff81100c6b>] ? time_hardirqs_off+0x9/0x14
[282735.240160]  [<ffffffff8108e87d>] ? trace_hardirqs_off_caller+0x1f/0xaa
[282735.256343] ---[ end trace a4539270c8056f93 ]---

Consider the following example:

  Parent snapshot:

  .                                                             (ino 256)
  |--- a/                                                       (ino 257)
  |    |--- c/                                                  (ino 260)
  |
  |--- del/                                                     (ino 259)
        |--- tmp/                                               (ino 258)
        |--- x/                                                 (ino 261)
        |--- y/                                                 (ino 262)

  Send snapshot:

  .                                                             (ino 256)
  |--- a/                                                       (ino 257)
  |    |--- x/                                                  (ino 261)
  |    |--- y/                                                  (ino 262)
  |
  |--- c/                                                       (ino 260)
       |--- tmp/                                                (ino 258)

1) When processing inode 258, we end up delaying its rename operation
   because it has an ancestor (in the send snapshot) that has a higher
   inode number (inode 260) which was also renamed in the send snapshot,
   therefore we delay the rename of inode 258 so that it happens after
   inode 260 is renamed;

2) When processing inode 259, we end up delaying its deletion (rmdir
   operation) because it has a child inode (258) that has its rename
   operation delayed. At this point we allocate an orphan_dir_info
   structure and tag inode 258 so that we later attempt to see if we
   can delete (rmdir) inode 259 once inode 258 is renamed;

3) When we process inode 260, after renaming it we finally do the rename
   operation for inode 258. Once we issue the rename operation for inode
   258 we notice that this inode was tagged so that we attempt to see
   if at this point we can delete (rmdir) inode 259. But at this point
   we can not still delete inode 259 because it has 2 children, inodes
   261 and 262, that were not yet processed and therefore not yet
   moved (renamed) away from inode 259. We end up not freeing the
   orphan_dir_info structure allocated in step 2;

4) We process inodes 261 and 262, and once we move/rename inode 262
   we issue the rmdir operation for inode 260;

5) We finish the send stream and notice that red black tree that
   contains orphan_dir_info structures is not empty, so we emit
   a warning and then free any orphan_dir_structures left.

So fix this by freeing an orphan_dir_info structure once we try to
apply a pending rename operation if we can not delete yet the tagged
directory.

A test case for fstests follows soon.

Signed-off-by: Robbie Ko <robbieko@synology.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
[Modified changelog to be more detailed and easier to understand]
2016-08-01 07:25:31 +01:00
Robbie Ko
99ea42ddb1 Btrfs: incremental send, fix premature rmdir operations
Under certain situations, an incremental send operation can contain
a rmdir operation that will make the receiving end fail when attempting
to execute it, because the target directory is not yet empty.

Consider the following example:

  Parent snapshot:

  .                                                             (ino 256)
  |--- a/                                                       (ino 257)
  |    |--- c/                                                  (ino 260)
  |
  |--- del/                                                     (ino 259)
        |--- tmp/                                               (ino 258)
        |--- x/                                                 (ino 261)

  Send snapshot:

  .                                                             (ino 256)
  |--- a/                                                       (ino 257)
  |    |--- x/                                                  (ino 261)
  |
  |--- c/                                                       (ino 260)
       |--- tmp/                                                (ino 258)

1) When processing inode 258, we delay its rename operation because inode
   260 is its new parent in the send snapshot and it was not yet renamed
   (since 260 > 258, that is, beyond the current progress);

2) When processing inode 259, we realize we can not yet send an rmdir
   operation (against inode 259) because inode 258 was still not yet
   renamed/moved away from inode 259. Therefore we update data structures
   so that after inode 258 is renamed, we try again to see if we can
   finally send an rmdir operation for inode 259;

3) When we process inode 260, we send a rename operation for it followed
   by a rename operation for inode 258. Once we send the rename operation
   for inode 258 we then check if we can finally issue an rmdir for its
   previous parent, inode 259, by calling the can_rmdir() function with
   a value of sctx->cur_ino + 1 (260 + 1 = 261) for its "progress"
   argument. This makes can_rmdir() return true (value 1) because even
   though there's still a child inode of inode 259 that was not yet
   renamed/moved, which is inode 261, the given value of progress (261)
   is not lower then 261 (that is, not lower than the inode number of
   some child of inode 259). So we end up sending a rmdir operation for
   inode 259 before its child inode 261 is processed and renamed.

So fix this by passing the correct progress value to the call to
can_rmdir() from within apply_dir_move() (where we issue delayed rename
operations), which should match stcx->cur_ino (the number of the inode
currently being processed) and not sctx->cur_ino + 1.

A test case for fstests follows soon.

Signed-off-by: Robbie Ko <robbieko@synology.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
[Rewrote change log to be more detailed, clear and well formatted]

Signed-off-by: Filipe Manana <fdmanana@suse.com>
2016-08-01 07:25:12 +01:00
Filipe Manana
4122ea64f8 Btrfs: incremental send, fix invalid paths for rename operations
Example scenario:

  Parent snapshot:

  .                                                       (ino 277)
  |---- tmp/                                              (ino 278)
  |---- pre/                                              (ino 280)
  |      |---- wait_dir/                                  (ino 281)
  |
  |---- desc/                                             (ino 282)
  |---- ance/                                             (ino 283)
  |       |---- below_ance/                               (ino 279)
  |
  |---- other_dir/                                        (ino 284)

  Send snapshot:

  .                                                       (ino 277)
  |---- tmp/                                              (ino 278)
         |---- other_dir/                                 (ino 284)
                   |---- below_ance/                      (ino 279)
                   |            |---- pre/                (ino 280)
                   |
                   |---- wait_dir/                        (ino 281)
                              |---- desc/                 (ino 282)
                                      |---- ance/         (ino 283)

While computing the send stream the following steps happen:

1) While processing inode 279 we end up delaying its rename operation
   because its new parent in the send snapshot, inode 284, was not
   yet processed and therefore not yet renamed;

2) Later when processing inode 280 we end up renaming it immediately to
   "ance/below_once/pre" and not delay its rename operation because its
   new parent (inode 279 in the send snapshot) has its rename operation
   delayed and inode 280 is not an encestor of inode 279 (its parent in
   the send snapshot) in the parent snapshot;

3) When processing inode 281 we end up delaying its rename operation
   because its new parent in the send snapshot, inode 284, was not yet
   processed and therefore not yet renamed;

4) When processing inode 282 we do not delay its rename operation because
   its parent in the send snapshot, inode 281, already has its own rename
   operation delayed and our current inode (282) is not an ancestor of
   inode 281 in the parent snapshot. Therefore inode 282 is renamed to
   "ance/below_ance/pre/wait_dir";

5) When processing inode 283 we realize that we can rename it because one
   of its ancestors in the send snapshot, inode 281, has its rename
   operation delayed and inode 283 is not an ancestor of inode 281 in the
   parent snapshot. So a rename operation to rename inode 283 to
   "ance/below_ance/pre/wait_dir/desc/ance" is issued. This path is
   invalid due to a missing path building loop that was undetected by
   the incremental send implementation, as inode 283 ends up getting
   included twice in the path (once with its path in the parent snapshot).
   Therefore its rename operation must wait before the ancestor inode 284
   is renamed.

Fix this by not terminating the rename dependency checks when we find an
ancestor, in the send snapshot, that has its rename operation delayed. So
that we continue doing the same checks if the current inode is not an
ancestor, in the parent snapshot, of an ancestor in the send snapshot we
are processing in the loop.

The problem and reproducer were reported by Robbie Ko, as part of a patch
titled "Btrfs: incremental send, avoid ancestor rename to descendant".
However the fix was unnecessarily complicated and can be addressed with
much less code and effort.

Reported-by: Robbie Ko <robbieko@synology.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
2016-08-01 07:24:45 +01:00
Filipe Manana
7969e77a73 Btrfs: send, add missing error check for calls to path_loop()
The function path_loop() can return a negative integer, signaling an
error, 0 if there's no path loop and 1 if there's a path loop. We were
treating any non zero values as meaning that a path loop exists. Fix
this by explicitly checking for errors and gracefully return them to
user space.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
2016-08-01 07:23:20 +01:00
Robbie Ko
801bec365e Btrfs: send, fix failure to move directories with the same name around
When doing an incremental send we can end up not moving directories that
have the same name. This happens when the same parent directory has
different child directories with the same name in the parent and send
snapshots.

For example, consider the following scenario:

  Parent snapshot:

  .                   (ino 256)
  |---- d/            (ino 257)
  |     |--- p1/      (ino 258)
  |
  |---- p1/           (ino 259)

  Send snapshot:

  .                    (ino 256)
  |--- d/              (ino 257)
       |--- p1/        (ino 259)
             |--- p1/  (ino 258)

The directory named "d" (inode 257) has in both snapshots an entry with
the name "p1" but it refers to different inodes in both snapshots (inode
258 in the parent snapshot and inode 259 in the send snapshot). When
attempting to move inode 258, the operation is delayed because its new
parent, inode 259, was not yet moved/renamed (as the stream is currently
processing inode 258). Then when processing inode 259, we also end up
delaying its move/rename operation so that it happens after inode 258 is
moved/renamed. This decision to delay the move/rename rename operation
of inode 259 is due to the fact that the new parent inode (257) still
has inode 258 as its child, which has the same name has inode 259. So
we end up with inode 258 move/rename operation waiting for inode's 259
move/rename operation, which in turn it waiting for inode's 258
move/rename. This results in ending the send stream without issuing
move/rename operations for inodes 258 and 259 and generating the
following warnings in syslog/dmesg:

[148402.979747] ------------[ cut here ]------------
[148402.980588] WARNING: CPU: 14 PID: 4117 at fs/btrfs/send.c:6177 btrfs_ioctl_send+0xe03/0xe51 [btrfs]
[148402.981928] Modules linked in: btrfs crc32c_generic xor raid6_pq acpi_cpufreq tpm_tis ppdev tpm parport_pc psmouse parport sg pcspkr i2c_piix4 i2c_core evdev processor serio_raw button loop autofs4 ext4 crc16 jbd2 mbcache sr_mod cdrom sd_mod ata_generic virtio_scsi ata_piix libata virtio_pci virtio_ring virtio e1000 scsi_mod floppy [last unloaded: btrfs]
[148402.986999] CPU: 14 PID: 4117 Comm: btrfs Tainted: G        W       4.6.0-rc7-btrfs-next-31+ #1
[148402.988136] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014
[148402.988136]  0000000000000000 ffff88022139fca8 ffffffff8126b42c 0000000000000000
[148402.988136]  0000000000000000 ffff88022139fce8 ffffffff81052b14 000018212139fac8
[148402.988136]  ffff88022b0db400 0000000000000000 0000000000000001 0000000000000000
[148402.988136] Call Trace:
[148402.988136]  [<ffffffff8126b42c>] dump_stack+0x67/0x90
[148402.988136]  [<ffffffff81052b14>] __warn+0xc2/0xdd
[148402.988136]  [<ffffffff81052beb>] warn_slowpath_null+0x1d/0x1f
[148402.988136]  [<ffffffffa04bc831>] btrfs_ioctl_send+0xe03/0xe51 [btrfs]
[148402.988136]  [<ffffffffa048b358>] btrfs_ioctl+0x14f/0x1f81 [btrfs]
[148402.988136]  [<ffffffff8108e456>] ? arch_local_irq_save+0x9/0xc
[148402.988136]  [<ffffffff8108eb51>] ? __lock_is_held+0x3c/0x57
[148402.988136]  [<ffffffff8118da05>] vfs_ioctl+0x18/0x34
[148402.988136]  [<ffffffff8118e00c>] do_vfs_ioctl+0x550/0x5be
[148402.988136]  [<ffffffff81196f0c>] ? __fget+0x6b/0x77
[148402.988136]  [<ffffffff81196fa1>] ? __fget_light+0x62/0x71
[148402.988136]  [<ffffffff8118e0d1>] SyS_ioctl+0x57/0x79
[148402.988136]  [<ffffffff8149e025>] entry_SYSCALL_64_fastpath+0x18/0xa8
[148402.988136]  [<ffffffff8108e89d>] ? trace_hardirqs_off_caller+0x3f/0xaa
[148403.011373] ---[ end trace a4539270c8056f8b ]---
[148403.012296] ------------[ cut here ]------------
[148403.013071] WARNING: CPU: 14 PID: 4117 at fs/btrfs/send.c:6194 btrfs_ioctl_send+0xe19/0xe51 [btrfs]
[148403.014447] Modules linked in: btrfs crc32c_generic xor raid6_pq acpi_cpufreq tpm_tis ppdev tpm parport_pc psmouse parport sg pcspkr i2c_piix4 i2c_core evdev processor serio_raw button loop autofs4 ext4 crc16 jbd2 mbcache sr_mod cdrom sd_mod ata_generic virtio_scsi ata_piix libata virtio_pci virtio_ring virtio e1000 scsi_mod floppy [last unloaded: btrfs]
[148403.019708] CPU: 14 PID: 4117 Comm: btrfs Tainted: G        W       4.6.0-rc7-btrfs-next-31+ #1
[148403.020104] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014
[148403.020104]  0000000000000000 ffff88022139fca8 ffffffff8126b42c 0000000000000000
[148403.020104]  0000000000000000 ffff88022139fce8 ffffffff81052b14 000018322139fac8
[148403.020104]  ffff88022b0db400 0000000000000000 0000000000000001 0000000000000000
[148403.020104] Call Trace:
[148403.020104]  [<ffffffff8126b42c>] dump_stack+0x67/0x90
[148403.020104]  [<ffffffff81052b14>] __warn+0xc2/0xdd
[148403.020104]  [<ffffffff81052beb>] warn_slowpath_null+0x1d/0x1f
[148403.020104]  [<ffffffffa04bc847>] btrfs_ioctl_send+0xe19/0xe51 [btrfs]
[148403.020104]  [<ffffffffa048b358>] btrfs_ioctl+0x14f/0x1f81 [btrfs]
[148403.020104]  [<ffffffff8108e456>] ? arch_local_irq_save+0x9/0xc
[148403.020104]  [<ffffffff8108eb51>] ? __lock_is_held+0x3c/0x57
[148403.020104]  [<ffffffff8118da05>] vfs_ioctl+0x18/0x34
[148403.020104]  [<ffffffff8118e00c>] do_vfs_ioctl+0x550/0x5be
[148403.020104]  [<ffffffff81196f0c>] ? __fget+0x6b/0x77
[148403.020104]  [<ffffffff81196fa1>] ? __fget_light+0x62/0x71
[148403.020104]  [<ffffffff8118e0d1>] SyS_ioctl+0x57/0x79
[148403.020104]  [<ffffffff8149e025>] entry_SYSCALL_64_fastpath+0x18/0xa8
[148403.020104]  [<ffffffff8108e89d>] ? trace_hardirqs_off_caller+0x3f/0xaa
[148403.038981] ---[ end trace a4539270c8056f8c ]---

There's another issue caused by similar (but more complex) changes in the
directory hierarchy that makes move/rename operations fail, described with
the following example:

  Parent snapshot:

  .
  |---- a/                                                   (ino 262)
  |     |---- c/                                             (ino 268)
  |
  |---- d/                                                   (ino 263)
        |---- ance/                                          (ino 267)
                |---- e/                                     (ino 264)
                |---- f/                                     (ino 265)
                |---- ance/                                  (ino 266)

  Send snapshot:

  .
  |---- a/                                                   (ino 262)
  |---- c/                                                   (ino 268)
  |     |---- ance/                                          (ino 267)
  |
  |---- d/                                                   (ino 263)
  |     |---- ance/                                          (ino 266)
  |
  |---- f/                                                   (ino 265)
        |---- e/                                             (ino 264)

When the inode 265 is processed, the path for inode 267 is computed, which
at that time corresponds to "d/ance", and it's stored in the names cache.
Later on when processing inode 266, we end up orphanizing (renaming to a
name matching the pattern o<ino>-<gen>-<seq>) inode 267 because it has
the same name as inode 266 and it's currently a child of the new parent
directory (inode 263) for inode 266. After the orphanization and while we
are still processing inode 266, a rename operation for inode 266 is
generated. However the source path for that rename operation is incorrect
because it ends up using the old, pre-orphanization, name of inode 267.
The no longer valid name for inode 267 was previously cached when
processing inode 265 and it remains usable and considered valid until
the inode currently being processed has a number greater than 267.
This resulted in the receiving side failing with the following error:

  ERROR: rename d/ance/ance -> d/ance failed: No such file or directory

So fix these issues by detecting such circular dependencies for rename
operations and by clearing the cached name of an inode once the inode
is orphanized.

A test case for fstests will follow soon.

Signed-off-by: Robbie Ko <robbieko@synology.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
[Rewrote change log to be more detailed and organized, and improved
 comments]

Signed-off-by: Filipe Manana <fdmanana@suse.com>
2016-08-01 07:23:10 +01:00
Filipe Manana
0596a9048b Btrfs: add missing check for writeback errors on fsync
When we start an fsync we start ordered extents for all delalloc ranges.
However before attempting to log the inode, we only wait for those ordered
extents if we are not doing a full sync (bit BTRFS_INODE_NEEDS_FULL_SYNC
is set in the inode's flags). This means that if an ordered extent
completes with an IO error before we check if we can skip logging the
inode, we will not catch and report the IO error to user space. This is
because on an IO error, when the ordered extent completes we do not
update the inode, so if the inode was not previously updated by the
current transaction we end up not logging it through calls to fsync and
therefore not check its mapping flags for the presence of IO errors.

Fix this by checking for errors in the flags of the inode's mapping when
we notice we can skip logging the inode.

This caused sporadic failures in the test generic/331 (which explicitly
tests for IO errors during an fsync call).

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
2016-08-01 07:21:13 +01:00
Linus Torvalds
ba929b6646 Merge branch 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs updates from Chris Mason:
 "This pull is dedicated to Josef's enospc rework, which we've been
  testing for a few releases now.  It fixes some early enospc problems
  and is dramatically faster.

  This also includes an updated fix for the delalloc accounting that
  happens after a fault in copy_from_user.  My patch in v4.7 was almost
  but not quite enough"

* 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: fix delalloc accounting after copy_from_user faults
  Btrfs: avoid deadlocks during reservations in btrfs_truncate_block
  Btrfs: use FLUSH_LIMIT for relocation in reserve_metadata_bytes
  Btrfs: fill relocation block rsv after allocation
  Btrfs: always use trans->block_rsv for orphans
  Btrfs: change how we calculate the global block rsv
  Btrfs: use root when checking need_async_flush
  Btrfs: don't bother kicking async if there's nothing to reclaim
  Btrfs: fix release reserved extents trace points
  Btrfs: add fsid to some tracepoints
  Btrfs: add tracepoints for flush events
  Btrfs: fix delalloc reservation amount tracepoint
  Btrfs: trace pinned extents
  Btrfs: introduce ticketed enospc infrastructure
  Btrfs: add tracepoint for adding block groups
  Btrfs: warn_on for unaccounted spaces
  Btrfs: change delayed reservation fallback behavior
  Btrfs: always reserve metadata for delalloc extents
  Btrfs: fix callers of btrfs_block_rsv_migrate
  Btrfs: add bytes_readonly to the spaceinfo at once
2016-07-31 21:27:32 -04:00
Linus Torvalds
0e06f5c0de Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton:

 - a few misc bits

 - ocfs2

 - most(?) of MM

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (125 commits)
  thp: fix comments of __pmd_trans_huge_lock()
  cgroup: remove unnecessary 0 check from css_from_id()
  cgroup: fix idr leak for the first cgroup root
  mm: memcontrol: fix documentation for compound parameter
  mm: memcontrol: remove BUG_ON in uncharge_list
  mm: fix build warnings in <linux/compaction.h>
  mm, thp: convert from optimistic swapin collapsing to conservative
  mm, thp: fix comment inconsistency for swapin readahead functions
  thp: update Documentation/{vm/transhuge,filesystems/proc}.txt
  shmem: split huge pages beyond i_size under memory pressure
  thp: introduce CONFIG_TRANSPARENT_HUGE_PAGECACHE
  khugepaged: add support of collapse for tmpfs/shmem pages
  shmem: make shmem_inode_info::lock irq-safe
  khugepaged: move up_read(mmap_sem) out of khugepaged_alloc_page()
  thp: extract khugepaged from mm/huge_memory.c
  shmem, thp: respect MADV_{NO,}HUGEPAGE for file mappings
  shmem: add huge pages support
  shmem: get_unmapped_area align huge page
  shmem: prepare huge= mount option and sysfs knob
  mm, rmap: account shmem thp pages
  ...
2016-07-26 19:55:54 -07:00
Michal Hocko
8a5c743e30 mm, memcg: use consistent gfp flags during readahead
Vladimir has noticed that we might declare memcg oom even during
readahead because read_pages only uses GFP_KERNEL (with mapping_gfp
restriction) while __do_page_cache_readahead uses
page_cache_alloc_readahead which adds __GFP_NORETRY to prevent from
OOMs.  This gfp mask discrepancy is really unfortunate and easily
fixable.  Drop page_cache_alloc_readahead() which only has one user and
outsource the gfp_mask logic into readahead_gfp_mask and propagate this
mask from __do_page_cache_readahead down to read_pages.

This alone would have only very limited impact as most filesystems are
implementing ->readpages and the common implementation mpage_readpages
does GFP_KERNEL (with mapping_gfp restriction) again.  We can tell it to
use readahead_gfp_mask instead as this function is called only during
readahead as well.  The same applies to read_cache_pages.

ext4 has its own ext4_mpage_readpages but the path which has pages !=
NULL can use the same gfp mask.  Btrfs, cifs, f2fs and orangefs are
doing a very similar pattern to mpage_readpages so the same can be
applied to them as well.

[akpm@linux-foundation.org: coding-style fixes]
[mhocko@suse.com: restrict gfp mask in mpage_alloc]
  Link: http://lkml.kernel.org/r/20160610074223.GC32285@dhcp22.suse.cz
Link: http://lkml.kernel.org/r/1465301556-26431-1-git-send-email-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Vladimir Davydov <vdavydov@parallels.com>
Cc: Chris Mason <clm@fb.com>
Cc: Steve French <sfrench@samba.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Jan Kara <jack@suse.cz>
Cc: Mike Marshall <hubcap@omnibond.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Changman Lee <cm224.lee@samsung.com>
Cc: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-26 16:19:19 -07:00
Linus Torvalds
d05d7f4079 Merge branch 'for-4.8/core' of git://git.kernel.dk/linux-block
Pull core block updates from Jens Axboe:

   - the big change is the cleanup from Mike Christie, cleaning up our
     uses of command types and modified flags.  This is what will throw
     some merge conflicts

   - regression fix for the above for btrfs, from Vincent

   - following up to the above, better packing of struct request from
     Christoph

   - a 2038 fix for blktrace from Arnd

   - a few trivial/spelling fixes from Bart Van Assche

   - a front merge check fix from Damien, which could cause issues on
     SMR drives

   - Atari partition fix from Gabriel

   - convert cfq to highres timers, since jiffies isn't granular enough
     for some devices these days.  From Jan and Jeff

   - CFQ priority boost fix idle classes, from me

   - cleanup series from Ming, improving our bio/bvec iteration

   - a direct issue fix for blk-mq from Omar

   - fix for plug merging not involving the IO scheduler, like we do for
     other types of merges.  From Tahsin

   - expose DAX type internally and through sysfs.  From Toshi and Yigal

* 'for-4.8/core' of git://git.kernel.dk/linux-block: (76 commits)
  block: Fix front merge check
  block: do not merge requests without consulting with io scheduler
  block: Fix spelling in a source code comment
  block: expose QUEUE_FLAG_DAX in sysfs
  block: add QUEUE_FLAG_DAX for devices to advertise their DAX support
  Btrfs: fix comparison in __btrfs_map_block()
  block: atari: Return early for unsupported sector size
  Doc: block: Fix a typo in queue-sysfs.txt
  cfq-iosched: Charge at least 1 jiffie instead of 1 ns
  cfq-iosched: Fix regression in bonnie++ rewrite performance
  cfq-iosched: Convert slice_resid from u64 to s64
  block: Convert fifo_time from ulong to u64
  blktrace: avoid using timespec
  block/blk-cgroup.c: Declare local symbols static
  block/bio-integrity.c: Add #include "blk.h"
  block/partition-generic.c: Remove a set-but-not-used variable
  block: bio: kill BIO_MAX_SIZE
  cfq-iosched: temporarily boost queue priority for idle classes
  block: drbd: avoid to use BIO_MAX_SIZE
  block: bio: remove BIO_MAX_SECTORS
  ...
2016-07-26 15:03:07 -07:00
Jeff Mahoney
66642832f0 btrfs: btrfs_abort_transaction, drop root parameter
__btrfs_abort_transaction doesn't use its root parameter except to
obtain an fs_info pointer.  We can obtain that from trans->root->fs_info
for now and from trans->fs_info in a later patch.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-07-26 13:54:26 +02:00
Jeff Mahoney
64b6358072 btrfs: add btrfs_trans_handle->fs_info pointer
btrfs_trans_handle->root is documented as for use for confirming
that the root passed in to start the transaction is the same as the
one ending it.  It's used in several places when an fs_info pointer
is needed, so let's just add an fs_info pointer directly.  Eventually,
the root pointer can be removed.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-07-26 13:54:26 +02:00
Jeff Mahoney
05f9a78012 btrfs: btrfs_relocate_chunk pass extent_root to btrfs_end_transaction
In btrfs_relocate_chunk, we get a transaction handle via
btrfs_start_trans_remove_block_group, which starts the transaction
using the extent root.  When we call btrfs_end_transaction, we're calling
it using the chunk root.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-07-26 13:54:25 +02:00
Jeff Mahoney
1db1ff92b6 btrfs: convert nodesize macros to static inlines
This patch converts the macros used to calculate various node
size limits to static inlines.  That way we get type checking for free.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-07-26 13:54:25 +02:00
Jeff Mahoney
14a1e067b4 btrfs: introduce BTRFS_MAX_ITEM_SIZE
We use BTRFS_LEAF_DATA_SIZE - sizeof(struct btrfs_item) in
several places.  This introduces a BTRFS_MAX_ITEM_SIZE macro to do the
same.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-07-26 13:54:24 +02:00
Jeff Mahoney
0c83b62e22 btrfs: cleanup, remove prototype for btrfs_find_root_ref
The function isn't implemented anywhere.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-07-26 13:54:23 +02:00
Jeff Mahoney
df3975652f btrfs: copy_to_sk drop unused root parameter
The root parameter for copy_to_sk is not used at all.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-07-26 13:54:23 +02:00
Jeff Mahoney
bd6c57dda6 btrfs: simpilify btrfs_subvol_inherit_props
We just need a superblock, but we look it up using two different
roots depending on the call site.  Let's just use a superblock
pointer initialized at the outset.

This is mostly for Coccinelle not to choke on my root push up set.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-07-26 13:54:22 +02:00
Jeff Mahoney
f5ee5c9ac5 btrfs: tests, use BTRFS_FS_STATE_DUMMY_FS_INFO instead of dummy root
Now that we have a dummy fs_info associated with each test that
uses a root, we don't need the DUMMY_ROOT bit anymore.  This lets
us make choices without needing an actual root like in e.g.
btrfs_find_create_tree_block.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-07-26 13:54:19 +02:00
Jeff Mahoney
7c0260ee09 btrfs: tests, require fs_info for root
This allows the upcoming patchset to push nodesize and sectorsize into
fs_info.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-07-26 13:53:18 +02:00
Jeff Mahoney
8632daae40 btrfs: tests, move initialization into tests/
We have all these stubs that only exist because they're called from
btrfs_run_sanity_tests, which is a static inside super.c.  Let's just
move it all into tests/btrfs-tests.c and only have one stub.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-07-26 13:53:17 +02:00
Jeff Mahoney
3cdde2240d btrfs: btrfs_test_opt and friends should take a btrfs_fs_info
btrfs_test_opt and friends only use the root pointer to access
the fs_info.  Let's pass the fs_info directly in preparation to
eliminate similar patterns all over btrfs.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-07-26 13:53:16 +02:00
Jeff Mahoney
bc074524e1 btrfs: prefix fsid to all trace events
When using trace events to debug a problem, it's impossible to determine
which file system generated a particular event.  This patch adds a
macro to prefix standard information to the head of a trace event.

The extent_state alloc/free events are all that's left without an
fs_info available.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-07-26 13:53:16 +02:00
Jeff Mahoney
cb001095ca btrfs: plumb fs_info into btrfs_work
In order to provide an fsid for trace events, we'll need a btrfs_fs_info
pointer.  The most lightweight way to do that for btrfs_work structures
is to associate it with the __btrfs_workqueue structure.  Each queued
btrfs_work structure has a workqueue associated with it, so that's
a natural fit.  It's a privately defined structures, so we add accessors
to retrieve the fs_info pointer.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-07-26 13:53:15 +02:00
David Sterba
9f8d49095b btrfs: remove obsolete part of comment in statfs
The mixed blockgroup reporting has been fixed by commit
ae02d1bd07
"btrfs: fix mixed block count of available space"

Signed-off-by: David Sterba <dsterba@suse.com>
2016-07-26 13:52:25 +02:00