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* Btrfs: fix ordered extent leak when failing to start a transactionLiu Bo2012-08-28
| | | | | | | | We cannot just return error before freeing ordered extent and releasing reserved space when we fail to start a transacion. Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
* Btrfs: fix a dio write regressionLiu Bo2012-08-28
| | | | | | | | | | | | | | This bug is introduced by commit 3b8bde746f6f9bd36a9f05f5f3b6e334318176a9 (Btrfs: lock extents as we map them in DIO). In dio write, we should unlock the section which we didn't do IO on in case that we fall back to buffered write. But we need to not only unlock the section but also cleanup reserved space for the section. This bug was found while running xfstests 133, with this 133 no longer complains. Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
* Btrfs: fix deadlock with freeze and sync V2Josef Bacik2012-08-28
| | | | | | | | | | | | We can deadlock with freeze right now because we unconditionally start a transaction in our ->sync_fs() call. To fix this just check and see if we have a running transaction to commit. This saves us from the deadlock because at this point we'll have the umount sem for the sb so we're safe from freezes coming in after we've done our check. With this patch the freeze xfstests no longer deadlocks. Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
* Btrfs: revert checksum error statistic which can cause a BUG()Stefan Behrens2012-08-28
| | | | | | | | | | | | | | | | Commit 442a4f6308e694e0fa6025708bd5e4e424bbf51c added btrfs device statistic counters for detected IO and checksum errors to Linux 3.5. The statistic part that counts checksum errors in end_bio_extent_readpage() can cause a BUG() in a subfunction: "kernel BUG at fs/btrfs/volumes.c:3762!" That part is reverted with the current patch. However, the counting of checksum errors in the scrub context remains active, and the counting of detected IO errors (read, write or flush errors) in all contexts remains active. Cc: stable <stable@vger.kernel.org> # 3.5 Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de> Signed-off-by: Chris Mason <chris.mason@oracle.com>
* Btrfs: remove superblock writing after fatal errorStefan Behrens2012-08-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With commit acce952b0, btrfs was changed to flag the filesystem with BTRFS_SUPER_FLAG_ERROR and switch to read-only mode after a fatal error happened like a write I/O errors of all mirrors. In such situations, on unmount, the superblock is written in btrfs_error_commit_super(). This is done with the intention to be able to evaluate the error flag on the next mount. A warning is printed in this case during the next mount and the log tree is ignored. The issue is that it is possible that the superblock points to a root that was not written (due to write I/O errors). The result is that the filesystem cannot be mounted. btrfsck also does not start and all the other btrfs-progs tools fail to start as well. However, mount -o recovery is working well and does the right things to recover the filesystem (i.e., don't use the log root, clear the free space cache and use the next mountable root that is stored in the root backup array). This patch removes the writing of the superblock when BTRFS_SUPER_FLAG_ERROR is set, and removes the handling of the error flag in the mount function. These lines can be used to reproduce the issue (using /dev/sdm): SCRATCH_DEV=/dev/sdm SCRATCH_MNT=/mnt echo 0 25165824 linear $SCRATCH_DEV 0 | dmsetup create foo ls -alLF /dev/mapper/foo mkfs.btrfs /dev/mapper/foo mount /dev/mapper/foo $SCRATCH_MNT echo bar > $SCRATCH_MNT/foo sync echo 0 25165824 error | dmsetup reload foo dmsetup resume foo ls -alF $SCRATCH_MNT touch $SCRATCH_MNT/1 ls -alF $SCRATCH_MNT sleep 35 echo 0 25165824 linear $SCRATCH_DEV 0 | dmsetup reload foo dmsetup resume foo sleep 1 umount $SCRATCH_MNT btrfsck /dev/mapper/foo dmsetup remove foo Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de> Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
* Btrfs: allow delayed refs to be mergedJosef Bacik2012-08-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Daniel Blueman reported a bug with fio+balance on a ramdisk setup. Basically what happens is the balance relocates a tree block which will drop the implicit refs for all of its children and adds a full backref. Once the block is relocated we have to add the implicit refs back, so when we cow the block again we add the implicit refs for its children back. The problem comes when the original drop ref doesn't get run before we add the implicit refs back. The delayed ref stuff will specifically prefer ADD operations over DROP to keep us from freeing up an extent that will have references to it, so we try to add the implicit ref before it is actually removed and we panic. This worked fine before because the add would have just canceled the drop out and we would have been fine. But the backref walking work needs to be able to freeze the delayed ref stuff in time so we have this ever increasing sequence number that gets attached to all new delayed ref updates which makes us not merge refs and we run into this issue. So to fix this we need to merge delayed refs. So everytime we run a clustered ref we need to try and merge all of its delayed refs. The backref walking stuff locks the delayed ref head before processing, so if we have it locked we are safe to merge any refs inside of the sequence number. If there is no sequence number we can merge all refs. Doing this not only fixes our bug but keeps the delayed ref code from adding and removing useless refs and batching together multiple refs into one search instead of one search per delayed ref, which will really help our commit times. I ran this with Daniels test and 276 and I haven't seen any problems. Thanks, Reported-by: Daniel J Blueman <daniel@quora.org> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
* Btrfs: fix enospc problems when deleting a subvolJosef Bacik2012-08-28
| | | | | | | | | | | | | | | | Subvol delete is a special kind of awful where we use the global reserve to cover the ENOSPC requirements. The problem is once we're done removing everything we do a btrfs_update_inode(), which by default will try to do the delayed update stuff which will use it's own reserve. There will be no space in this reserve and we'll return ENOSPC. So instead use btrfs_update_inode_fallback() which will just fallback to updating the inode item in the case of enospc. This is fine because the global reserve covers the space requirements for this. With this patch I can now delete a subvol on a problem image Dave Sterba sent me. Thanks, Reported-by: David Sterba <dave@jikos.cz> Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
* Btrfs: fix wrong mtime and ctime when creating snapshotsMiao Xie2012-08-28
| | | | | | | | When we created a new snapshot, the mtime and ctime of its parent directory were not updated. Fix it. Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
* Btrfs: fix race in run_clustered_refsArne Jansen2012-08-28
| | | | | | | | | | | | | | | | | | | With commit commit d1270cd91f308c9d22b2804720c36ccd32dbc35e Author: Arne Jansen <sensille@gmx.net> Date: Tue Sep 13 15:16:43 2011 +0200 Btrfs: put back delayed refs that are too new I added a window where the delayed_ref's head->ref_mod code can diverge from the sum of the remaining refs, because we release the head->mutex in the middle. This leads to btrfs_lookup_extent_info returning wrong numbers. This patch fixes this by adjusting the head's ref_mod with each delayed ref we run. Signed-off-by: Arne Jansen <sensille@gmx.net> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
* Btrfs: don't run __tree_mod_log_free_eb on leavesChris Mason2012-08-28
| | | | | | | | When we split a leaf, we may end up inserting a new root on top of that leaf. The reflog code was incorrectly assuming the old root was always a node. This makes sure we skip over leaves. Signed-off-by: Chris Mason <chris.mason@fusionio.com>
* Btrfs: increase the size of the free space cacheJosef Bacik2012-08-28
| | | | | | | | | | | | | Arne was complaining about the space cache having mismatching generation numbers when debugging a deadlock. This is because we can run out of space in our preallocated range for our space cache if you have a pretty fragmented amount of space in your pinned space. So just increase the amount of space we preallocate for space cache so we can be sure to have enough space. This will only really affect data ranges since their the only chunks that end up larger than 256MB. Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
* Btrfs: barrier before waitqueue_activeJosef Bacik2012-08-28
| | | | | | | | | | We need a barrir before calling waitqueue_active otherwise we will miss wakeups. So in places that do atomic_dec(); then atomic_read() use atomic_dec_return() which imply a memory barrier (see memory-barriers.txt) and then add an explicit memory barrier everywhere else that need them. Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com>
* Btrfs: fix deadlock in wait_for_more_refsArne Jansen2012-08-28
| | | | | | | | | | | | | | | | Commit a168650c introduced a waiting mechanism to prevent busy waiting in btrfs_run_delayed_refs. This can deadlock with btrfs_run_ordered_operations, where a tree_mod_seq is held while waiting for the io to complete, while the end_io calls btrfs_run_delayed_refs. This whole mechanism is unnecessary. If not enough runnable refs are available to satisfy count, just return as count is more like a guideline than a strict requirement. In case we have to run all refs, commit transaction makes sure that no other threads are working in the transaction anymore, so we just assert here that no refs are blocked. Signed-off-by: Arne Jansen <sensille@gmx.net> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
* btrfs: fix second lock in btrfs_delete_delayed_items()Fengguang Wu2012-08-28
| | | | | | | | Fix a real bug caught by coccinelle. fs/btrfs/delayed-inode.c:1013:1-11: second lock on line 1013 Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
* Btrfs: don't allocate a seperate csums array for direct readsJosef Bacik2012-08-28
| | | | | | | | | | | | We've been allocating a big array for csums instead of storing them in the io_tree like we do for buffered reads because previously we were locking the entire range, so we didn't have an extent state for each sector of the range. But now that we do the range locking as we map the buffers we can limit the mapping lenght to sectorsize and use the private part of the io_tree for our csums. This allows us to avoid an extra memory allocation for direct reads which could incur latency. Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com>
* Btrfs: do not strdup non existent stringsJosef Bacik2012-08-28
| | | | | | | | | When we close devices we add back empty devices for some reason that escapes me. In the case of a missing dev we don't allocate an rcu_string for it's name, so check to see if the device has a name and if it doesn't don't bother strdup()'ing it. Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com>
* Btrfs: do not use missing devices when showing devnameJosef Bacik2012-08-28
| | | | | | | | | | | | | | | If you do the following mkfs.btrfs /dev/sdb /dev/sdc rmmod btrfs dd if=/dev/zero of=/dev/sdb bs=1M count=1 mount -o degraded /dev/sdc /mnt/btrfs-test the box will panic trying to deref the name for the missing dev since it is the lower numbered devid. So fix show_devname to not use missing devices. Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com>
* Btrfs: fix that error value is changed by mistakeStefan Behrens2012-08-28
| | | | | | | | | In iterate_inodes_from_logical() the error result from extent_from_logical() is patched by mistake. Typically ENOENT is patched to EINVAL because (-ENOENT & BTRFS_EXTENT_FLAG_TREE_BLOCK) evaluates to true. Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
* Btrfs: lock extents as we map them in DIOJosef Bacik2012-08-28
| | | | | | | | | | | | | | | | | | | | | | A deadlock in xfstests 113 was uncovered by commit d187663ef24cd3d033f0cbf2867e70b36a3a90b8 This is because we would not return EIOCBQUEUED for short AIO reads, instead we'd wait for the DIO to complete and then return the amount of data we transferred, which would allow our stuff to unlock the remaning amount. But with this change this no longer happens, so if we have a short AIO read (for example if we try to read past EOF), we could leave the section from EOF to the end of where we tried to read locked. Fixing this is tricky since there is no clear way to know exactly how much data DIO truly submitted for IO, so to make this less hard on ourselves and less combersome we need to lock the extents as we try to map them, and then we unlock any areas we didn't actually map. This makes us completely safe from deadlocks and reliance on a particular behavior of the DIO code. This also lays the groundwork for allowing us to use the normal csum storage method for reads which means we can remove an allocation. Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com>
* Btrfs: fix some endian bugs handling the root timesDan Carpenter2012-08-28
| | | | | | | "trans->transid" is cpu endian but we want to store the data as little endian. "item->ctime.nsec" is only 32 bits, not 64. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
* Btrfs: unlock on error in btrfs_delalloc_reserve_metadata()Dan Carpenter2012-08-28
| | | | | | We should release this mutex before returning the error code. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
* Btrfs: checking for NULL instead of IS_ERRDan Carpenter2012-08-28
| | | | | | add_qgroup_rb() never returns NULL, only error pointers. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
* Btrfs: fix some error codes in btrfs_qgroup_inherit()Dan Carpenter2012-08-28
| | | | | | | These are returning zero when it should be returning a negative error code. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
* Btrfs: fix a misplaced address operator in a conditionStefan Behrens2012-08-28
| | | | | | This should obviously not be "if (&flag)" but "if (flag)". Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
* Btrfs: uninit variable fixes in send/receiveChris Mason2012-07-25
| | | | Signed-off-by: Chris Mason <chris.mason@fusionio.com>
* Merge branch 'send-v2' of git://github.com/ablock84/linux-btrfs into for-linusChris Mason2012-07-25
|\ | | | | | | | | | | | | | | | | | | | | | | | | This is the kernel portion of btrfs send/receive Conflicts: fs/btrfs/Makefile fs/btrfs/backref.h fs/btrfs/ctree.c fs/btrfs/ioctl.c fs/btrfs/ioctl.h Signed-off-by: Chris Mason <chris.mason@fusionio.com>
| * Btrfs: introduce BTRFS_IOC_SEND for btrfs send/receiveAlexander Block2012-07-25
| | | | | | | | | | | | | | | | | | | | | | | | | | This patch introduces the BTRFS_IOC_SEND ioctl that is required for send. It allows btrfs-progs to implement full and incremental sends. Patches for btrfs-progs will follow. Signed-off-by: Alexander Block <ablock84@googlemail.com> Reviewed-by: David Sterba <dave@jikos.cz> Reviewed-by: Arne Jansen <sensille@gmx.net> Reviewed-by: Jan Schmidt <list.btrfs@jan-o-sch.net> Reviewed-by: Alex Lyakas <alex.bolshoy.btrfs@gmail.com>
| * Btrfs: add btrfs_compare_trees functionAlexander Block2012-07-25
| | | | | | | | | | | | | | | | | | | | | | | | This function is used to find the differences between two trees. The tree compare skips whole subtrees if it detects shared tree blocks and thus is pretty fast. Signed-off-by: Alexander Block <ablock84@googlemail.com> Reviewed-by: David Sterba <dave@jikos.cz> Reviewed-by: Arne Jansen <sensille@gmx.net> Reviewed-by: Jan Schmidt <list.btrfs@jan-o-sch.net> Reviewed-by: Alex Lyakas <alex.bolshoy.btrfs@gmail.com>
| * Btrfs: introduce subvol uuids and timesAlexander Block2012-07-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch introduces uuids for subvolumes. Each subvolume has it's own uuid. In case it was snapshotted, it also contains parent_uuid. In case it was received, it also contains received_uuid. It also introduces subvolume ctime/otime/stime/rtime. The first two are comparable to the times found in inodes. otime is the origin/creation time and ctime is the change time. stime/rtime are only valid on received subvolumes. stime is the time of the subvolume when it was sent. rtime is the time of the subvolume when it was received. Additionally to the times, we have a transid for each time. They are updated at the same place as the times. btrfs receive uses stransid and rtransid to find out if a received subvolume changed in the meantime. If an older kernel mounts a filesystem with the extented fields, all fields become invalid. The next mount with a new kernel will detect this and reset the fields. Signed-off-by: Alexander Block <ablock84@googlemail.com> Reviewed-by: David Sterba <dave@jikos.cz> Reviewed-by: Arne Jansen <sensille@gmx.net> Reviewed-by: Jan Schmidt <list.btrfs@jan-o-sch.net> Reviewed-by: Alex Lyakas <alex.bolshoy.btrfs@gmail.com>
| * Btrfs: make iref_to_path non staticAlexander Block2012-07-25
| | | | | | | | | | | | | | Make iref_to_path non static (needed in send) and rename it to btrfs_iref_to_path Signed-off-by: Alexander Block <ablock84@googlemail.com>
| * Btrfs: add helper for tree enumerationArne Jansen2012-07-25
| | | | | | | | | | | | | | | | | | Often no exact match is wanted but just the next lower or higher item. There's a lot of duplicated code throughout btrfs to deal with the corner cases. This patch adds a helper function that can facilitate searching. Signed-off-by: Arne Jansen <sensille@gmx.net>
| * btrfs: allow cross-subvolume file cloneDavid Sterba2012-07-25
| | | | | | | | | | | | | | | | | | Lift the EXDEV condition and allow different root trees for files being cloned, then pass source inode's root when searching for extents. Cloning is not allowed to cross vfsmounts, ie. when two subvolumes from one filesystem are mounted separately. Signed-off-by: David Sterba <dsterba@suse.cz>
* | Btrfs: add a barrier before a waitqueue_active checkChris Mason2012-07-25
| | | | | | | | | | | | | | We were missing wakeups on the delayed ref waitqueue due to races on waitqueue_active. Signed-off-by: Chris Mason <chris.mason@fusionio.com>
* | Btrfs: call the ordered free operation without any locks heldChris Mason2012-07-25
| | | | | | | | | | | | | | | | | | | | | | | | | | Each ordered operation has a free callback, and this was called with the worker spinlock held. Josef made the free callback also call iput, which we can't do with the spinlock. This drops the spinlock for the free operation and grabs it again before moving through the rest of the list. We'll circle back around to this and find a cleaner way that doesn't bounce the lock around so much. Signed-off-by: Chris Mason <chris.mason@fusionio.com> cc: stable@kernel.org
* | Btrfs: Check INCOMPAT flags on remount and add helper functionMitch Harder2012-07-25
| | | | | | | | | | | | | | | | | | | | | | | | | | In support of the recently added capability to remount with lzo compression, provide a helper function to check the compression INCOMPAT flags when remounting with lzo compression, and set the flags if necessary. Also, implement the new helper function when defragmenting with explicit lzo compression and when setting the default subvolume. Signed-off-by: Mitch Harder <mitch.harder@sabayonlinux.org> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
* | Merge branch 'qgroup' of git://git.jan-o-sch.net/btrfs-unstable into for-linusChris Mason2012-07-25
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: fs/btrfs/ioctl.c fs/btrfs/ioctl.h fs/btrfs/transaction.c fs/btrfs/transaction.h Signed-off-by: Chris Mason <chris.mason@fusionio.com>
| * | Btrfs: add qgroup inheritanceArne Jansen2012-07-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When creating a subvolume or snapshot, it is necessary to initialize the qgroup account with a copy of some other (tracking) qgroup. This patch adds parameters to the ioctls to pass the information from which qgroup to inherit. Signed-off-by: Arne Jansen <sensille@gmx.net>
| * | Btrfs: add qgroup ioctlsArne Jansen2012-07-12
| | | | | | | | | | | | | | | | | | | | | Ioctls to control the qgroup feature like adding and removing qgroups and assigning qgroups. Signed-off-by: Arne Jansen <sensille@gmx.net>
| * | Btrfs: hooks to reserve qgroup spaceArne Jansen2012-07-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Like block reserves, reserve a small piece of space on each transaction start and for delalloc. These are the hooks that can actually return EDQUOT to the user. The amount of space reserved is tracked in the transaction handle. Signed-off-by: Arne Jansen <sensille@gmx.net>
| * | Btrfs: hooks for qgroup to record delayed refsJan Schmidt2012-07-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | Hooks into qgroup code to record refs and into transaction commit. This is the main entry point for qgroup. Basically every change in extent backrefs got accounted to the appropriate qgroups. Signed-off-by: Arne Jansen <sensille@gmx.net> Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
| * | Btrfs: quota tree support and startupArne Jansen2012-07-12
| | | | | | | | | | | | | | | | | | | | | | | | Init the quota tree along with the others on open_ctree and close_ctree. Add the quota tree to the list of well known trees in btrfs_read_fs_root_no_name. Signed-off-by: Arne Jansen <sensille@gmx.net>
| * | Btrfs: call the qgroup accounting functionsJan Schmidt2012-07-12
| | | | | | | | | | | | Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
| * | Btrfs: qgroup implementation and prototypesArne Jansen2012-07-12
| | | | | | | | | | | | | | | Signed-off-by: Arne Jansen <sensille@gmx.net> Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
| * | Btrfs: Test code to change the order of delayed-ref processingArne Jansen2012-07-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Normally delayed refs get processed in ascending bytenr order. This correlates in most cases to the order added. To expose dependencies on this order, we start to process the tree in the middle instead of the beginning. This code is only effective when SCRAMBLE_DELAYED_REFS is defined. Signed-off-by: Arne Jansen <sensille@gmx.net>
| * | Btrfs: qgroup state and initializationArne Jansen2012-07-10
| | | | | | | | | | | | | | | | | | Add state to fs_info. Signed-off-by: Arne Jansen <sensille@gmx.net>
| * | Btrfs: added helper to create new treesArne Jansen2012-07-10
| | | | | | | | | | | | | | | | | | | | | This creates a brand new tree. Will be used to create the quota tree. Signed-off-by: Arne Jansen <sensille@gmx.net>
| * | Btrfs: check the root passed to btrfs_end_transactionArne Jansen2012-07-10
| | | | | | | | | | | | | | | | | | | | | | | | This patch only add a consistancy check to validate that the same root is passed to start_transaction and end_transaction. Subvolume quota depends on this. Signed-off-by: Arne Jansen <sensille@gmx.net>
| * | Btrfs: add helper for tree enumerationArne Jansen2012-07-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | Often no exact match is wanted but just the next lower or higher item. There's a lot of duplicated code throughout btrfs to deal with the corner cases. This patch adds a helper function that can facilitate searching. Signed-off-by: Arne Jansen <sensille@gmx.net>
| * | Btrfs: qgroup on-disk formatArne Jansen2012-07-10
| | | | | | | | | | | | | | | | | | | | | Not all features are in use by the current version and thus may change in the future. Signed-off-by: Arne Jansen <sensille@gmx.net>
| * | Btrfs: join tree mod log code with the code holding back delayed refsJan Schmidt2012-07-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We've got two mechanisms both required for reliable backref resolving (tree mod log and holding back delayed refs). You cannot make use of one without the other. So instead of requiring the user of this mechanism to setup both correctly, we join them into a single interface. Additionally, we stop inserting non-blockers into fs_info->tree_mod_seq_list as we did before, which was of no value. Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>