There is another bug in the tree mod log stuff in that we're calling
tree_mod_log_free_eb every single time a block is cow'ed. The problem with this
is that if this block is shared by multiple snapshots we will call this multiple
times per block, so if we go to rewind the mod log for this block we'll BUG_ON()
in __tree_mod_log_rewind because we try to rewind a free twice. We only want to
call tree_mod_log_free_eb if we are actually freeing the block. With this patch
I no longer hit the panic in __tree_mod_log_rewind. Thanks,
Cc: stable@vger.kernel.org
Reviewed-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
We need to hold the tree mod log lock in __tree_mod_log_rewind since we walk
forward in the tree mod entries, otherwise we'll end up with random entries and
trip the BUG_ON() at the front of __tree_mod_log_rewind. This fixes the panics
people were seeing when running
find /whatever -type f -exec btrfs fi defrag {} \;
Thansk,
Cc: stable@vger.kernel.org
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
This patch does two things. First we no longer explicitly read in the blocks
we're trying to readahead. For things like balance_level we may never actually
use the blocks so this just adds uneeded latency, and balance_level and
split_node will both read in the blocks they care about explicitly so if the
blocks need to be waited on it will be done there. Secondly we no longer drop
the path if we do readahead, we just set the path blocking before we call
reada_for_balance() and then we're good to go. Hopefully this will cut down on
the number of re-searches. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
This patch does two things, first it only does one call to
btrfs_buffer_uptodate() with the gen specified instead of once with 0 and then
again with gen specified. The other thing is to call btrfs_read_buffer() on the
buffer we've found instead of dropping it and then calling read_tree_block().
This will keep us from doing yet another radix tree lookup for a buffer we've
already found. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
During splitting a leaf, pushing items around to hopefully get some space only
works when we have a parent, ie. we have at least one sibling leaf.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
As for splitting a leaf, root is just the leaf, and tree mod log does not apply
on leaf, so in this case, we don't do log_removal.
As for splitting a node, the old root is kept as a normal node and we have nicely
put records in tree mod log for moving keys and items, so in this case we don't do
that either.
As above, insert_new_root can get rid of log_removal.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
The size parameter to btrfs_extend_item() is the number of bytes
to add to the item, not the size of the item after the operation
(like it is for btrfs_truncate_item(), there the size parameter
is not the number of bytes to take away, but the total size of
the item after truncation).
Fix it in the comment.
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Chris hit a bug where we weren't finding extent records when running extent ops.
This is because we use the delayed_ref_head when running the extent op, which
means we can't use the ->type checks to see if we are metadata. We also lose
the level of the metadata we are working on. So to fix this we can just check
the ->is_data section of the extent_op, and we can store the level of the buffer
we were modifying in the extent_op. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Big patch, but all it does is add statics to functions which
are in fact static, then remove the associated dead-code fallout.
removed functions:
btrfs_iref_to_path()
__btrfs_lookup_delayed_deletion_item()
__btrfs_search_delayed_insertion_item()
__btrfs_search_delayed_deletion_item()
find_eb_for_page()
btrfs_find_block_group()
range_straddles_pages()
extent_range_uptodate()
btrfs_file_extent_length()
btrfs_scrub_cancel_devid()
btrfs_start_transaction_lflush()
btrfs_print_tree() is left because it is used for debugging.
btrfs_start_transaction_lflush() and btrfs_reada_detach() are
left for symmetry.
ulist.c functions are left, another patch will take care of those.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Sequence numbers for delayed refs have been introduced in the first version
of the qgroup patch set. To solve the problem of find_all_roots on a busy
file system, the tree mod log was introduced. The sequence numbers for that
were simply shared between those two users.
However, at one point in qgroup's quota accounting, there's a statement
accessing the previous sequence number, that's still just doing (seq - 1)
just as it would have to in the very first version.
To satisfy that requirement, this patch makes the sequence number counter 64
bit and splits it into a major part (used for qgroup sequence number
counting) and a minor part (incremented for each tree modification in the
log). This enables us to go exactly one major step backwards, as required
for qgroups, while still incrementing the sequence counter for tree mod log
insertions to keep track of their order. Keeping them in a single variable
means there's no need to change all the code dealing with comparisons of two
sequence numbers.
The sequence number is reset to 0 on commit (not new in this patch), which
ensures we won't overflow the two 32 bit counters.
Without this fix, the qgroup tracking can occasionally go wrong and WARN_ONs
from the tree mod log code may happen.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
We kept leaking extent buffers when mounting a broken file system and it turns
out it's because not everybody uses read_tree_block properly. You need to check
and make sure the extent_buffer is uptodate before you use it. This patch fixes
everybody who calls read_tree_block directly to make sure they check that it is
uptodate and free it and return an error if it is not. With this we no longer
leak EB's when things go horribly wrong. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Argument 'trans' is not used in btrfs_extend_item().
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
If argument 'trans' is unnecessary in the function where
fixup_low_keys() is called, 'trans' is deleted.
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Argument 'trans' is not used in fixup_low_keys(). So, remove it.
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
When tree_mod_log_rewind decides to make a copy of the current tree buffer
for its modifications, it subsequently freed the buffer before unlocking it.
Obviously, those operations are required in reverse order.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
The tree mod log functions were accessing root->node->... directly, without
use of btrfs_root_node() or explicit rcu locking. This could lead to an
extent buffer reference being leaked and another reference being freed too
early when preemtion was enabled.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Commit d9abbf1c changed tree mod log locking around ROOT_REPLACE operations.
When a tree root is split, however, we were logging removal of all elements
from the root node before logging removal of half of the elements for the
split operation. This leads to a BUG_ON when rewinding.
This commit removes the erroneous logging of removal of all elements.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
A user sent me a btrfs-image of a file system that was panicing on mount during
the log recovery. I had originally thought these problems were from a bug in
the free space cache code, but that was just a symptom of the problem. The
problem is if your application does something like this
[prealloc][prealloc][prealloc]
the internal extent maps will merge those all together into one extent map, even
though on disk they are 3 separate extents. So if you go to write into one of
these ranges the extent map will be right since we use the physical extent when
doing the write, but when we log the extents they will use the wrong sizes for
the remainder prealloc space. If this doesn't happen to trip up the free space
cache (which it won't in a lot of cases) then you will get bogus entries in your
extent tree which will screw stuff up later. The data and such will still work,
but everything else is broken. This patch fixes this by not allowing extents
that are on the modified list to be merged. This has the side effect that we
are no longer adding everything to the modified list all the time, which means
we now have to call btrfs_drop_extents every time we log an extent into the
tree. So this allows me to drop all this speciality code I was using to get
around calling btrfs_drop_extents. With this patch the testcase I've created no
longer creates a bogus file system after replaying the log. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
We currently store the first key of the tree block inside the reference for the
tree block in the extent tree. This takes up quite a bit of space. Make a new
key type for metadata which holds the level as the offset and completely removes
storing the btrfs_tree_block_info inside the extent ref. This reduces the size
from 51 bytes to 33 bytes per extent reference for each tree block. In practice
this results in a 30-35% decrease in the size of our extent tree, which means we
COW less and can keep more of the extent tree in memory which makes our heavy
metadata operations go much faster. This is not an automatic format change, you
must enable it at mkfs time or with btrfstune. This patch deals with having
metadata stored as either the old format or the new format so it is easy to
convert. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
To resolve backrefs, ROOT_REPLACE operations in the tree mod log are
required to be tied to at least one KEY_REMOVE_WHILE_FREEING operation.
Therefore, those operations must be enclosed by tree_mod_log_write_lock()
and tree_mod_log_write_unlock() calls.
Those calls are private to the tree_mod_log_* functions, which means that
removal of the elements of an old root node must be logged from
tree_mod_log_insert_root. This partly reverts and corrects commit ba1bfbd5
(Btrfs: fix a tree mod logging issue for root replacement operations).
This fixes the brand-new version of xfstest 276 as of commit cfe73f71.
Cc: stable@vger.kernel.org
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
The entry point at the defrag ioctl always sets "cache only" to 0;
the codepaths haven't run for a long time as far as I can
tell. Chris says they're dead code, so remove them.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
When replaying a log tree with qgroups enabled, tree_mod_log_rewind does a
sanity-check of the number of items against the maximum possible number.
It calculates that number with the nodesize of fs_root. Unfortunately
fs_root is not yet set at this stage. So instead use the nodesize from
tree_root, which is already initialized.
Signed-off-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
This reverts commit 6a7a665d78.
This was bug was fixed differently in 3.6, so this commit
isn't needed.
Conflicts:
fs/btrfs/ctree.c
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
This reverts commit 95c80bb1f6.
The bug addressed by this commit was fixed differently back in 3.6
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
I noticed while doing fsync tests that we were always dropping the path and
re-searching when we first cow the log root even though we've already gotten
the write lock on the root. That's because we don't take into account that
there might not be a parent node, so fix the check to make sure there is
actually a parent node before we undo all of this work for nothing. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
This gets called at least 4 times for every level while adding an object,
and it involves 3 kmapping calls, which on my box take about 5us a piece.
So instead use a token, which brings us down to 1 kmap call and makes this
function take 1/3 of the time per call. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
We don't really need to copy extents from the source tree since we have all
of the information already available to us in the extent_map tree. So
instead just write the extents straight to the log tree and don't bother to
copy the extent items from the source tree.
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
You'd think path->keep_locks would keep all the locks wouldn't you? You'd
be wrong. It only keeps them if the slot is pointing to the last item in
the node. This is for use with btrfs_next_leaf, which needs this sort of
thing. But the horrible horrible things I'm going to do to the tree log
means I really need everything held from root to leaf so I can add and
delete items in the same search. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Originally root_times_lock was introduced as part of send/receive
code however newly developed patch to label the subvol reused
the same lock, so renaming it for a meaningful name.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Just use WARN_ON rather than an if containing only WARN_ON(1).
A simplified version of the semantic patch that makes this transformation
is as follows: (http://coccinelle.lip6.fr/)
// <smpl>
@@
expression e;
@@
- if (e) WARN_ON(1);
+ WARN_ON(e);
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Use WARN rather than printk followed by WARN_ON(1), for conciseness.
A simplified version of the semantic patch that makes this transformation
is as follows: (http://coccinelle.lip6.fr/)
// <smpl>
@@
expression list es;
@@
-printk(
+WARN(1,
es);
-WARN_ON(1);
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
The argument 'tree_mod_log' is not necessary since all of callers enable it.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Since we don't use MOD_LOG_KEY_REMOVE_WHILE_MOVING to add nritems
during rewinding, we should insert a MOD_LOG_KEY_REMOVE operation first.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Key MOD_LOG_KEY_REMOVE_WHILE_MOVING means that we're doing memmove inside
an extent buffer node, and the node's number of items remains unchanged
(unless we are inserting a single pointer, but we have MOD_LOG_KEY_ADD for that).
So we don't need to increase node's number of items during rewinding,
otherwise we may get an node larger than leafsize and cause general protection
errors later.
Here is the details,
- If we do memory move for inserting a single pointer, we need to
add node's nritems by one, and we honor MOD_LOG_KEY_ADD for adding.
- If we do memory move for deleting a single pointer, we need to
decrease node's nritems by one, and we honor MOD_LOG_KEY_REMOVE for
deleting.
- If we do memory move for balance left/right, we need to decrease
node's nritems, and we honor MOD_LOG_KEY_REMOVE for balaning.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
After cloning root's node, we forgot to dec the src's ref
which can lead to a memory leak.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Emphasis the way tree_mod_log_insert_move avoids adding
MOD_LOG_KEY_REMOVE_WHILE_MOVING operations, depending on the direction of
the move operation.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
In get_old_root we grab a lock on the extent buffer before we obtain a
reference on that buffer. That order is changed now.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
In btrfs_find_all_roots' termination condition, we compare the level of the
old buffer we got from btrfs_search_old_slot to the level of the current
root node. We'd better compare it to the level of the rewinded root node.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Tree mod log treated old root buffers as always empty buffers when starting
the rewind operations. However, the old root may still be part of the
current tree at a lower level, with still some valid entries.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Avoid the implicit free by tree_mod_log_set_root_pointer, which is wrong in
two places. Where needed, we call tree_mod_log_free_eb explicitly now.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Independant of the check (push_items < src_items) tree_mod_log_eb_copy did
log the removal of the old data entries from the source buffer. Therefore,
we must not call tree_mod_log_eb_move if the check evaluates to true, as
that would log the removal twice, finally resulting in (rewinded) buffers
with wrong values for header_nritems.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
The btrfs send code was assuming the offset of the file item into the
extent translated to bytes on disk. If we're compressed, this isn't
true, and so it was off into extents owned by other files.
It was also improperly handling inline extents. This solves a crash
where we may have gone past the end of the file extent item by not
testing early enough for an inline extent. It also solves problems
where we have a whole between the end of the inline item and the start
of the full extent.
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
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>
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>
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>
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>
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>
Josef Bacik