We will try and reserve metadata bytes in btrfs_block_rsv_check and if we cannot
because we have a transaction open it will return EAGAIN, so we do not need to
try and commit the transaction again.
Signed-off-by: Josef Bacik <josef@redhat.com>
The priority and refill_used flags are not used anymore, and neither is the
usage counter, so just remove them from btrfs_block_rsv.
Signed-off-by: Josef Bacik <josef@redhat.com>
We have not been reserving enough space for checksums. We were just reserving
bytes for the checksum items themselves, we were not taking into account having
to cow the tree and such. This patch adds a csum_bytes counter to the inode for
keeping track of the number of bytes outstanding we have for checksums. Then we
calculate how many leaves would be required for the checksums we are given and
use that to reserve space. This adds a significant amount of bytes to our
reservations, but we will handle this later. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
We have been using bytes_reserved for metadata reservations, which is wrong
since we use that to keep track of outstanding reservations from the allocator.
This resulted in us doing a lot of silly things to make sure we don't allocate a
bunch of metadata chunks since we never had a real view of how much space was
actually in use by metadata.
This passes Arne's enospc test and xfstests as well as my own enospc tests.
Hopefully this will get us moving in the right direction. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
btrfs_bio is a bio abstraction able to split and not complete after the last
bio has returned (like the old btrfs_multi_bio). Additionally, btrfs_bio
tracks the mirror_num used to read data which can be used for error
correction purposes.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
This fixes a regression introduced by commit cdcb725c05 ("Btrfs: check
if there is enough space for balancing smarter"). We can't do 64-bit
divides on 32-bit architectures.
In cases where we need to divide/multiply by 2 we should just left/right
shift respectively, and in cases where theres N number of devices use
do_div. Also make the counters u64 to match up with rw_devices.
Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Acked-and-tested-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The filesystem turns readonly instead of returning the error to the
caller when detected error in btrfs_drop_snapshot().
and, because the caller doesn't check the error, the function type is
changed to 'void'.
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
When checking if there is enough space for balancing a block group,
since we do not take raid types into consideration, we do not account
corrent amounts of space that we needed. This makes us do some extra
work before we get ENOSPC.
Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
We have a problem where if a user specifies discard but doesn't actually support
it we will return EOPNOTSUPP from btrfs_discard_extent. This is a problem
because this gets called (in a fashion) from the tree log recovery code, which
has a nice little BUG_ON(ret) after it, which causes us to fail the tree log
replay. So instead detect wether our devices support discard when we're adding
them and then don't issue discards if we know that the device doesn't support
it. And just for good measure set ret = 0 in btrfs_issue_discard just in case
we still get EOPNOTSUPP so we don't screw anybody up like this again. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
In __btrfs_free_extent we will print the leaf if we fail to find the extent we
wanted, but the problem is if we get an error we won't have a leaf so often this
leads to a NULL pointer dereference and we lose the error that actually
occurred. So only print the leaf if ret > 0, which means we didn't find the
item we were looking for but we didn't error either. This way the error is
preserved.
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Here I have a two SSD-partitions btrfs, and they are defaultly set to
"data=raid0, metadata=raid1", then I try to fill my btrfs partition
till "No space left on device", via "dd if=/dev/zero of=/mnt/btrfs/tmp".
I get an oops panic from kernel BUG at fs/btrfs/extent-tree.c:5199!, which
refers to find_free_extent's
BUG_ON(index != get_block_group_index(block_group));
In SSD mode, in order to find enough space to alloc, we may check the
block_group cache which has been checked sometime before, but the index is not
updated, where it hits the BUG_ON.
Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Acked-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
The access for ro in btrfs_block_group_cache should be protected
because of the racy lock in relocation.
Signed-off-by: Wu Bo <wu.bo@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
When btrfs_unlink_inode() and btrfs_orphan_add() in btrfs_unlink()
are error, the error code is returned to the caller instead of
BUG_ON().
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
The btrfs transaction code will return any errors that come from
reserve_metadata_bytes. We need to make sure we don't return funny
things like 1 or EAGAIN.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
This patch was originally from Tejun Heo. lockdep complains about the btrfs
locking because we sometimes take btree locks from two different trees at the
same time. The current classes are based only on level in the btree, which
isn't enough information for lockdep to figure out if the lock is safe.
This patch makes a class for each type of tree, and lumps all the FS trees that
actually have files and directories into the same class.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
The btrfs metadata btree is the source of significant
lock contention, especially in the root node. This
commit changes our locking to use a reader/writer
lock.
The lock is built on top of rw spinlocks, and it
extends the lock tracking to remember if we have a
read lock or a write lock when we go to blocking. Atomics
count the number of blocking readers or writers at any
given time.
It removes all of the adaptive spinning from the old code
and uses only the spinning/blocking hints inside of btrfs
to decide when it should continue spinning.
In read heavy workloads this is dramatically faster. In write
heavy workloads we're still faster because of less contention
on the root node lock.
We suffer slightly in dbench because we schedule more often
during write locks, but all other benchmarks so far are improved.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
When we balanced the chunks across the devices, BUG_ON() in
__finish_chunk_alloc() was triggered.
------------[ cut here ]------------
kernel BUG at fs/btrfs/volumes.c:2568!
[SNIP]
Call Trace:
[<ffffffffa049525e>] btrfs_alloc_chunk+0x8e/0xa0 [btrfs]
[<ffffffffa04546b0>] do_chunk_alloc+0x330/0x3a0 [btrfs]
[<ffffffffa045c654>] btrfs_reserve_extent+0xb4/0x1f0 [btrfs]
[<ffffffffa045c86b>] btrfs_alloc_free_block+0xdb/0x350 [btrfs]
[<ffffffffa048a8d8>] ? read_extent_buffer+0xd8/0x1d0 [btrfs]
[<ffffffffa04476fd>] __btrfs_cow_block+0x14d/0x5e0 [btrfs]
[<ffffffffa044660d>] ? read_block_for_search+0x14d/0x4d0 [btrfs]
[<ffffffffa0447c9b>] btrfs_cow_block+0x10b/0x240 [btrfs]
[<ffffffffa044dd5e>] btrfs_search_slot+0x49e/0x7a0 [btrfs]
[<ffffffffa044f07d>] btrfs_insert_empty_items+0x8d/0xf0 [btrfs]
[<ffffffffa045e973>] insert_with_overflow+0x43/0x110 [btrfs]
[<ffffffffa045eb0d>] btrfs_insert_dir_item+0xcd/0x1f0 [btrfs]
[<ffffffffa0489bd0>] ? map_extent_buffer+0xb0/0xc0 [btrfs]
[<ffffffff812276ad>] ? rb_insert_color+0x9d/0x160
[<ffffffffa046cc40>] ? inode_tree_add+0xf0/0x150 [btrfs]
[<ffffffffa0474801>] btrfs_add_link+0xc1/0x1c0 [btrfs]
[<ffffffff811dacac>] ? security_inode_init_security+0x1c/0x30
[<ffffffffa04a28aa>] ? btrfs_init_acl+0x4a/0x180 [btrfs]
[<ffffffffa047492f>] btrfs_add_nondir+0x2f/0x70 [btrfs]
[<ffffffffa046af16>] ? btrfs_init_inode_security+0x46/0x60 [btrfs]
[<ffffffffa0474ac0>] btrfs_create+0x150/0x1d0 [btrfs]
[<ffffffff81159c63>] ? generic_permission+0x23/0xb0
[<ffffffff8115b415>] vfs_create+0xa5/0xc0
[<ffffffff8115ce6e>] do_last+0x5fe/0x880
[<ffffffff8115dc0d>] path_openat+0xcd/0x3d0
[<ffffffff8115e029>] do_filp_open+0x49/0xa0
[<ffffffff8116a965>] ? alloc_fd+0x95/0x160
[<ffffffff8114f0c7>] do_sys_open+0x107/0x1e0
[<ffffffff810bcc3f>] ? audit_syscall_entry+0x1bf/0x1f0
[<ffffffff8114f1e0>] sys_open+0x20/0x30
[<ffffffff81484ec2>] system_call_fastpath+0x16/0x1b
[SNIP]
RIP [<ffffffffa049444a>] __finish_chunk_alloc+0x20a/0x220 [btrfs]
The reason is:
Task1 Space balance task
do_chunk_alloc()
__finish_chunk_alloc()
update device info
in the chunk tree
alloc system metadata block
relocate system metadata block group
set system metadata block group
readonly, This block group is the
only one that can allocate space. So
there is no free space that can be
allocated now.
find no space and don't try
to alloc new chunk, and then
return ENOSPC
BUG_ON() in __finish_chunk_alloc()
was triggered.
Fix this bug by allocating a new system metadata chunk before relocating the
old one if we find there is no free space which can be allocated after setting
the old block group to be read-only.
Reported-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Tested-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
So I had this brilliant idea to use atomic counters for outstanding and reserved
extents, but this turned out to be a bad idea. Consider this where we have 1
outstanding extent and 1 reserved extent
Reserver Releaser
atomic_dec(outstanding) now 0
atomic_read(outstanding)+1 get 1
atomic_read(reserved) get 1
don't actually reserve anything because
they are the same
atomic_cmpxchg(reserved, 1, 0)
atomic_inc(outstanding)
atomic_add(0, reserved)
free reserved space for 1 extent
Then the reserver now has no actual space reserved for it, and when it goes to
finish the ordered IO it won't have enough space to do it's allocation and you
get those lovely warnings.
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Kill the check to see if we have 512mb of reserved space in delalloc and
shrink_delalloc if we do. This causes unexpected latencies and we have other
logic to see if we need to throttle. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
A user reported a deadlock when copying a bunch of files. This is because they
were low on memory and kthreadd got hung up trying to migrate pages for an
allocation when starting the caching kthread. The page was locked by the person
starting the caching kthread. To fix this we just need to use the async thread
stuff so that the threads are already created and we don't have to worry about
deadlocks. Thanks,
Reported-by: Roman Mamedov <rm@romanrm.ru>
Signed-off-by: Josef Bacik <josef@redhat.com>
In addition to properly handling allocation failure from btrfs_alloc_path, I
also fixed up the kzalloc error handling code immediately below it.
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
I also removed the BUG_ON from error return of find_next_chunk in
init_first_rw_device(). It turns out that the only caller of
init_first_rw_device() also BUGS on any nonzero return so no actual behavior
change has occurred here.
do_chunk_alloc() also needed an update since it calls btrfs_alloc_chunk()
which can now return -ENOMEM. Instead of setting space_info->full on any
error from btrfs_alloc_chunk() I catch and return every error value _except_
-ENOSPC. Thanks goes to Tsutomu Itoh for pointing that issue out.
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
This patch fixes many callers of btrfs_alloc_path() which BUG_ON allocation
failure. All the sites that are fixed in this patch were checked by me to
be fairly trivial to fix because of at least one of two criteria:
- Callers of the function catch errors from it already so bubbling the
error up will be handled.
- Callers of the function might BUG_ON any nonzero return code in which
case there is no behavior changed (but we still got to remove a BUG_ON)
The following functions were updated:
btrfs_lookup_extent, alloc_reserved_tree_block, btrfs_remove_block_group,
btrfs_lookup_csums_range, btrfs_csum_file_blocks, btrfs_mark_extent_written,
btrfs_inode_by_name, btrfs_new_inode, btrfs_symlink,
insert_reserved_file_extent, and run_delalloc_nocow
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
We keep having problems with early enospc, and that's because our method of
making space is inherently racy. The problem is we can have one guy trying to
make space for himself, and in the meantime people come in and steal his
reservation. In order to stop this we make a waitqueue and put anybody who
comes into reserve_metadata_bytes on that waitqueue if somebody is trying to
make more space. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
We have to do weird things when handling enospc in the transaction joining code.
Because we've already joined the transaction we cannot commit the transaction
within the reservation code since it will deadlock, so we have to return EAGAIN
and then make sure we don't retry too many times. Instead of doing this, just
do the reservation the normal way before we join the transaction, that way we
can do whatever we want to try and reclaim space, and then if it fails we know
for sure we are out of space and we can return ENOSPC. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
data parameter should be u64 because a full-sized chunk flags field is
passed instead of 0/1 for distinguishing data from metadata. All
underlying functions expect u64.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
I was testing with empty_cluster = 0 to try and reproduce a problem and kept
hitting early enospc panics. This was because our loop logic was a little
confused. So this is what I did
1) Make the loop variable the ultimate decider on wether we should loop again
isntead of checking to see if we had an uncached bg, empty size or empty
cluster.
2) Increment loop before checking to see what we are on to make the loop
definitions make more sense.
3) If we are on the chunk alloc loop don't set empty_size/empty_cluster to 0
unless we didn't actually allocate a chunk. If we did allocate a chunk we
should be able to easily setup a new cluster so clearing
empty_size/empty_cluster makes us less efficient.
This kept me from hitting panics while trying to reproduce the other problem.
Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
I noticed when running an enospc test that we would get stuck committing the
transaction in check_data_space even though we truly didn't have enough space.
So check to see if bytes_pinned is bigger than num_bytes, if it's not don't
commit the transaction. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Currently, btrfs_truncate_item and btrfs_extend_item returns only 0.
So, the check by BUG_ON in the caller is unnecessary.
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Observed as a large delay when --mixed filesystem is filled up.
Test example:
1. create tiny --mixed FS:
$ dd if=/dev/zero of=2G.img seek=$((2048 * 1024 * 1024 - 1)) count=1 bs=1
$ mkfs.btrfs --mixed 2G.img
$ mount -oloop 2G.img /mnt/ut/
2. Try to fill it up:
$ dd if=/dev/urandom of=10M.file bs=10240 count=1024
$ seq 1 256 | while read file_no; do echo $file_no; time cp 10M.file ${file_no}.copy; done
Up to '200.copy' it goes fast, but when disk fills-up each -ENOSPC
message takes 3 seconds to pop-up _every_ ENOSPC (and in usermode linux
it's even more: 30-60 seconds!). (Maybe, time depends on kernel's timer resolution).
No IO, no CPU load, just rescheduling. Some debugging revealed busy spinning
in shrink_delalloc.
Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>
Reviewed-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
If we have a very large filesystem, we can spend a lot of time in
find_free_extent just trying to allocate from empty block groups. So instead
check to see if the block group even has enough space for the allocation, and if
not go on to the next block group.
Signed-off-by: Josef Bacik <josef@redhat.com>
Our readahead is sort of sloppy, and really isn't always needed. For example if
ls is doing a stating ls (which is the default) it's going to stat in non-disk
order, so if say you have a directory with a stupid amount of files, readahead
is going to do nothing but waste time in the case of doing the stat. Taking the
unconditional readahead out made my test go from 57 minutes to 36 minutes. This
means that everywhere we do loop through the tree we want to make sure we do set
path->reada properly, so I went through and found all of the places where we
loop through the path and set reada to 1. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
When the fs is super full and we unmount the fs, we could get stuck in this
thing where unmount is waiting for the caching kthread to make progress and the
caching kthread keeps scheduling because we're in the middle of a commit. So
instead just let the caching kthread keep going and only yeild if
need_resched(). This makes my horrible umount case go from taking up to 10
minutes to taking less than 20 seconds. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Originally this was going to be used as a way to give hints to the allocator,
but frankly we can get much better hints elsewhere and it's not even used at all
for anything usefull. In addition to be completely useless, when we initialize
an inode we try and find a freeish block group to set as the inodes block group,
and with a completely full 40gb fs this takes _forever_, so I imagine with say
1tb fs this is just unbearable. So just axe the thing altoghether, we don't
need it and it saves us 8 bytes in the inode and saves us 500 microseconds per
inode lookup in my testcase. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
The ceph guys keep running into problems where we have space reserved in our
orphan block rsv when freeing it up. This is because they tend to do snapshots
alot, so their truncates tend to use a bunch of space, so when we go to do
things like update the inode we have to steal reservation space in order to make
the reservation happen. This happens because truncate can use as much space as
it freaking feels like, but we still have to hold space for removing the orphan
item and updating the inode, which will definitely always happen. So in order
to fix this we need to split all of the reservation stuf up. So with this patch
we have
1) The orphan block reserve which only holds the space for deleting our orphan
item when everything is over.
2) The truncate block reserve which gets allocated and used specifically for the
space that the truncate will use on a per truncate basis.
3) The transaction will always have 1 item's worth of data reserved so we can
update the inode normally.
Hopefully this will make the ceph problem go away. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
We use trans_mutex for lots of things, here's a basic list
1) To serialize trans_handles joining the currently running transaction
2) To make sure that no new trans handles are started while we are committing
3) To protect the dead_roots list and the transaction lists
Really the serializing trans_handles joining is not too hard, and can really get
bogged down in acquiring a reference to the transaction. So replace the
trans_mutex with a trans_lock spinlock and use it to do the following
1) Protect fs_info->running_transaction. All trans handles have to do is check
this, and then take a reference of the transaction and keep on going.
2) Protect the fs_info->trans_list. This doesn't get used too much, basically
it just holds the current transactions, which will usually just be the currently
committing transaction and the currently running transaction at most.
3) Protect the dead roots list. This is only ever processed by splicing the
list so this is relatively simple.
4) Protect the fs_info->reloc_ctl stuff. This is very lightweight and was using
the trans_mutex before, so this is a pretty straightforward change.
5) Protect fs_info->no_trans_join. Because we don't hold the trans_lock over
the entirety of the commit we need to have a way to block new people from
creating a new transaction while we're doing our work. So we set no_trans_join
and in join_transaction we test to see if that is set, and if it is we do a
wait_on_commit.
6) Make the transaction use count atomic so we don't need to take locks to
modify it when we're dropping references.
7) Add a commit_lock to the transaction to make sure multiple people trying to
commit the same transaction don't race and commit at the same time.
8) Make open_ioctl_trans an atomic so we don't have to take any locks for ioctl
trans.
I have tested this with xfstests, but obviously it is a pretty hairy change so
lots of testing is greatly appreciated. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
I keep forgetting that btrfs_join_transaction() just ignores the num_items
argument, which leads me to sending pointless patches and looking stupid :). So
just kill the num_items argument from btrfs_join_transaction and
btrfs_start_ioctl_transaction, since neither of them use it. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Changelog V5 -> V6:
- Fix oom when the memory load is high, by storing the delayed nodes into the
root's radix tree, and letting btrfs inodes go.
Changelog V4 -> V5:
- Fix the race on adding the delayed node to the inode, which is spotted by
Chris Mason.
- Merge Chris Mason's incremental patch into this patch.
- Fix deadlock between readdir() and memory fault, which is reported by
Itaru Kitayama.
Changelog V3 -> V4:
- Fix nested lock, which is reported by Itaru Kitayama, by updating space cache
inode in time.
Changelog V2 -> V3:
- Fix the race between the delayed worker and the task which does delayed items
balance, which is reported by Tsutomu Itoh.
- Modify the patch address David Sterba's comment.
- Fix the bug of the cpu recursion spinlock, reported by Chris Mason
Changelog V1 -> V2:
- break up the global rb-tree, use a list to manage the delayed nodes,
which is created for every directory and file, and used to manage the
delayed directory name index items and the delayed inode item.
- introduce a worker to deal with the delayed nodes.
Compare with Ext3/4, the performance of file creation and deletion on btrfs
is very poor. the reason is that btrfs must do a lot of b+ tree insertions,
such as inode item, directory name item, directory name index and so on.
If we can do some delayed b+ tree insertion or deletion, we can improve the
performance, so we made this patch which implemented delayed directory name
index insertion/deletion and delayed inode update.
Implementation:
- introduce a delayed root object into the filesystem, that use two lists to
manage the delayed nodes which are created for every file/directory.
One is used to manage all the delayed nodes that have delayed items. And the
other is used to manage the delayed nodes which is waiting to be dealt with
by the work thread.
- Every delayed node has two rb-tree, one is used to manage the directory name
index which is going to be inserted into b+ tree, and the other is used to
manage the directory name index which is going to be deleted from b+ tree.
- introduce a worker to deal with the delayed operation. This worker is used
to deal with the works of the delayed directory name index items insertion
and deletion and the delayed inode update.
When the delayed items is beyond the lower limit, we create works for some
delayed nodes and insert them into the work queue of the worker, and then
go back.
When the delayed items is beyond the upper bound, we create works for all
the delayed nodes that haven't been dealt with, and insert them into the work
queue of the worker, and then wait for that the untreated items is below some
threshold value.
- When we want to insert a directory name index into b+ tree, we just add the
information into the delayed inserting rb-tree.
And then we check the number of the delayed items and do delayed items
balance. (The balance policy is above.)
- When we want to delete a directory name index from the b+ tree, we search it
in the inserting rb-tree at first. If we look it up, just drop it. If not,
add the key of it into the delayed deleting rb-tree.
Similar to the delayed inserting rb-tree, we also check the number of the
delayed items and do delayed items balance.
(The same to inserting manipulation)
- When we want to update the metadata of some inode, we cached the data of the
inode into the delayed node. the worker will flush it into the b+ tree after
dealing with the delayed insertion and deletion.
- We will move the delayed node to the tail of the list after we access the
delayed node, By this way, we can cache more delayed items and merge more
inode updates.
- If we want to commit transaction, we will deal with all the delayed node.
- the delayed node will be freed when we free the btrfs inode.
- Before we log the inode items, we commit all the directory name index items
and the delayed inode update.
I did a quick test by the benchmark tool[1] and found we can improve the
performance of file creation by ~15%, and file deletion by ~20%.
Before applying this patch:
Create files:
Total files: 50000
Total time: 1.096108
Average time: 0.000022
Delete files:
Total files: 50000
Total time: 1.510403
Average time: 0.000030
After applying this patch:
Create files:
Total files: 50000
Total time: 0.932899
Average time: 0.000019
Delete files:
Total files: 50000
Total time: 1.215732
Average time: 0.000024
[1] http://marc.info/?l=linux-btrfs&m=128212635122920&q=p3
Many thanks for Kitayama-san's help!
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: David Sterba <dave@jikos.cz>
Tested-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Tested-by: Itaru Kitayama <kitayama@cl.bb4u.ne.jp>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
When a btrfs disk is created by mixed data & metadata option, it will have no
pure data or pure metadata space info.
In btrfs's for-linus branch, commit 78b1ea13838039cd88afdd62519b40b344d6c920
(Btrfs: fix OOPS of empty filesystem after balance) initializes space infos at
the very beginning. The problem is this initialization does not take the mixed
case into account, which will cause btrfs will easily get into ENOSPC in mixed
case.
Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Remove code which has been #if0-ed out for a very long time and does not
seem to be related to current codebase anymore.
Signed-off-by: David Sterba <dsterba@suse.cz>
parameter tree root it's not used since commit
5f39d397df ("Btrfs: Create extent_buffer
interface for large blocksizes")
Signed-off-by: David Sterba <dsterba@suse.cz>
The check on the return value of kmalloc() is added to some places.
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
This is similar to block group caching.
We dedicate a special inode in fs tree to save free ino cache.
At the very first time we create/delete a file after mount, the free ino
cache will be loaded from disk into memory. When the fs tree is commited,
the cache will be written back to disk.
To keep compatibility, we check the root generation against the generation
of the special inode when loading the cache, so the loading will fail
if the btrfs filesystem was mounted in an older kernel before.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
There's a potential problem in 32bit system when we exhaust 32bit inode
numbers and start to allocate big inode numbers, because btrfs uses
inode->i_ino in many places.
So here we always use BTRFS_I(inode)->location.objectid, which is an
u64 variable.
There are 2 exceptions that BTRFS_I(inode)->location.objectid !=
inode->i_ino: the btree inode (0 vs 1) and empty subvol dirs (256 vs 2),
and inode->i_ino will be used in those cases.
Another reason to make this change is I'm going to use a special inode
to save free ino cache, and the inode number must be > (u64)-256.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
So we can re-use the code to cache free inode numbers.
The change is quite straightforward. Two new structures are introduced.
- struct btrfs_free_space_ctl
We move those variables that are used for caching free space from
struct btrfs_block_group_cache to this new struct.
- struct btrfs_free_space_op
We do block group specific work (e.g. calculation of extents threshold)
through functions registered in this struct.
And then we can remove references to struct btrfs_block_group_cache.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Everytime we try to allocate disk space we try and see if we can pre-emptively
allocate a chunk, but in the common case we don't allocate anything, so there is
no sense in taking the chunk_mutex at all. So instead if we are allocating a
chunk, mark it in the space_info so we don't get two people trying to allocate
at the same time. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Reviewed-by: Liu Bo <liubo2009@cn.fujitsu.com>
find_free_extent likes to allocate in contiguous clusters,
which makes writeback faster, especially on SSD storage. As
the FS fragments, these clusters become harder to find and we have
to decide between allocating a new chunk to make more clusters
or giving up on the cluster to allocate from the free space
we have.
Right now it creates too many chunks, and you can end up with
a whole FS that is mostly empty metadata chunks. This commit
changes the allocation code to be more strict and only
allocate new chunks when we've made good use of the chunks we
already have.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
btrfs will remove unused block groups after balance.
When a empty filesystem is balanced, the block group with tag "DATA" may be
dropped, and after umount and mount again, it will not find "DATA" space_info
and lead to OOPS.
So we initial the necessary space_infos(DATA, SYSTEM, METADATA) to avoid OOPS.
Reported-by: Daniel J Blueman <daniel.blueman@gmail.com>
Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
After Josef's patch(commit 3c14874acc),
btrfs will exclude super bytes when reading block groups(by marking a extent
state UPTODATE). However, these bytes do not get freed while balance remove
unused block groups, and we won't process those removed ones any more, when
we do umount and unload the btrfs module, btrfs hits a memory leak.
This patch add the missing free operation.
Reproduce steps:
$ mkfs.btrfs disk
$ mount disk /mnt/btrfs -o loop
$ btrfs filesystem balance /mnt/btrfs
$ umount /mnt/btrfs
$ rmmod btrfs
Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
To make Btrfs code more robust, several return value checks where memory
allocation can fail are introduced. I use BUG_ON where I don't know how
to handle the error properly, which increases the number of using the
notorious BUG_ON, though.
Signed-off-by: Yoshinori Sano <yoshinori.sano@gmail.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
We take an free extent out from allocator, trim it, then put it back,
but before we trim the block group, we should make sure the block group is
cached, so plus a little change to make cache_block_group() run without a
transaction.
Signed-off-by: Li Dongyang <lidongyang@novell.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Callers of btrfs_discard_extent() should check if we are mounted with -o discard,
as we want to make fitrim to work even the fs is not mounted with -o discard.
Also we should use REQ_DISCARD to map the free extent to get a full mapping,
last we only return errors if
1. the error is not a EOPNOTSUPP
2. no device supports discard
Signed-off-by: Li Dongyang <lidongyang@novell.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Make the function public as we should update the reserved extents calculations
after taking out an extent for trimming.
Signed-off-by: Li Dongyang <lidongyang@novell.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
In the filesystem context, we must allocate memory by GFP_NOFS,
or we may start another filesystem operation and make kswap thread hang up.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
This patch is checking return value of read_tree_block(),
and if it is NULL, error processing.
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
This patch changes some BUG_ON() to the error return.
(but, most callers still use BUG_ON())
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Tracepoints can provide insight into why btrfs hits bugs and be greatly
helpful for debugging, e.g
dd-7822 [000] 2121.641088: btrfs_inode_request: root = 5(FS_TREE), gen = 4, ino = 256, blocks = 8, disk_i_size = 0, last_trans = 8, logged_trans = 0
dd-7822 [000] 2121.641100: btrfs_inode_new: root = 5(FS_TREE), gen = 8, ino = 257, blocks = 0, disk_i_size = 0, last_trans = 0, logged_trans = 0
btrfs-transacti-7804 [001] 2146.935420: btrfs_cow_block: root = 2(EXTENT_TREE), refs = 2, orig_buf = 29368320 (orig_level = 0), cow_buf = 29388800 (cow_level = 0)
btrfs-transacti-7804 [001] 2146.935473: btrfs_cow_block: root = 1(ROOT_TREE), refs = 2, orig_buf = 29364224 (orig_level = 0), cow_buf = 29392896 (cow_level = 0)
btrfs-transacti-7804 [001] 2146.972221: btrfs_transaction_commit: root = 1(ROOT_TREE), gen = 8
flush-btrfs-2-7821 [001] 2155.824210: btrfs_chunk_alloc: root = 3(CHUNK_TREE), offset = 1103101952, size = 1073741824, num_stripes = 1, sub_stripes = 0, type = DATA
flush-btrfs-2-7821 [001] 2155.824241: btrfs_cow_block: root = 2(EXTENT_TREE), refs = 2, orig_buf = 29388800 (orig_level = 0), cow_buf = 29396992 (cow_level = 0)
flush-btrfs-2-7821 [001] 2155.824255: btrfs_cow_block: root = 4(DEV_TREE), refs = 2, orig_buf = 29372416 (orig_level = 0), cow_buf = 29401088 (cow_level = 0)
flush-btrfs-2-7821 [000] 2155.824329: btrfs_cow_block: root = 3(CHUNK_TREE), refs = 2, orig_buf = 20971520 (orig_level = 0), cow_buf = 20975616 (cow_level = 0)
btrfs-endio-wri-7800 [001] 2155.898019: btrfs_cow_block: root = 5(FS_TREE), refs = 2, orig_buf = 29384704 (orig_level = 0), cow_buf = 29405184 (cow_level = 0)
btrfs-endio-wri-7800 [001] 2155.898043: btrfs_cow_block: root = 7(CSUM_TREE), refs = 2, orig_buf = 29376512 (orig_level = 0), cow_buf = 29409280 (cow_level = 0)
Here is what I have added:
1) ordere_extent:
btrfs_ordered_extent_add
btrfs_ordered_extent_remove
btrfs_ordered_extent_start
btrfs_ordered_extent_put
These provide critical information to understand how ordered_extents are
updated.
2) extent_map:
btrfs_get_extent
extent_map is used in both read and write cases, and it is useful for tracking
how btrfs specific IO is running.
3) writepage:
__extent_writepage
btrfs_writepage_end_io_hook
Pages are cirtical resourses and produce a lot of corner cases during writeback,
so it is valuable to know how page is written to disk.
4) inode:
btrfs_inode_new
btrfs_inode_request
btrfs_inode_evict
These can show where and when a inode is created, when a inode is evicted.
5) sync:
btrfs_sync_file
btrfs_sync_fs
These show sync arguments.
6) transaction:
btrfs_transaction_commit
In transaction based filesystem, it will be useful to know the generation and
who does commit.
7) back reference and cow:
btrfs_delayed_tree_ref
btrfs_delayed_data_ref
btrfs_delayed_ref_head
btrfs_cow_block
Btrfs natively supports back references, these tracepoints are helpful on
understanding btrfs's COW mechanism.
8) chunk:
btrfs_chunk_alloc
btrfs_chunk_free
Chunk is a link between physical offset and logical offset, and stands for space
infomation in btrfs, and these are helpful on tracing space things.
9) reserved_extent:
btrfs_reserved_extent_alloc
btrfs_reserved_extent_free
These can show how btrfs uses its space.
Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Currently if we have corrupted items things will blow up in spectacular ways.
So as we read in blocks and they are leaves, check the entire leaf to make sure
all of the items are correct and point to valid parts in the leaf for the item
data the are responsible for. If the item is corrupt we will kick back EIO and
not read any of the copies since they are likely to not be correct either. This
will catch generic corruptions, it will be up to the individual callers of
btrfs_search_slot to make sure their items are right. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
If we cannot truncate an inode for some reason we will never delete the orphan
item associated with that inode, which means that we will loop forever in
btrfs_orphan_cleanup. Instead of doing this just return error so we fail to
mount. It sucks, but hey it's better than hanging. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
We track delayed allocation per inodes via 2 counters, one is
outstanding_extents and reserved_extents. Outstanding_extents is already an
atomic_t, but reserved_extents is not and is protected by a spinlock. So
convert this to an atomic_t and instead of using a spinlock, use atomic_cmpxchg
when releasing delalloc bytes. This makes our inode 72 bytes smaller, and
reduces locking overhead (albiet it was minimal to begin with). Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
Btrfs: break out of shrink_delalloc earlier
btrfs: fix not enough reserved space
btrfs: fix dip leak
Btrfs: make sure not to return overlapping extents to fiemap
Btrfs: deal with short returns from copy_from_user
Btrfs: fix regressions in copy_from_user handling
Josef had changed shrink_delalloc to exit after three shrink
attempts, which wasn't quite enough because new writers could
race in and steal free space.
But it also fixed deadlocks and stalls as we tried to recover
delalloc reservations. The code was tweaked to loop 1024
times, and would reset the counter any time a small amount
of progress was made. This was too drastic, and with a
lot of writers we can end up stuck in shrink_delalloc forever.
The shrink_delalloc loop is fairly complex because the caller is looping
too, and the caller will go ahead and force a transaction commit to make
sure we reclaim space.
This reworks things to exit shrink_delalloc when we've forced some
writeback and the delalloc reservations have gone down. This means
the writeback has not just started but has also finished at
least some of the metadata changes required to reclaim delalloc
space.
If we've got this wrong, we're returning ENOSPC too early, which
is a big improvement over the current behavior of hanging the machine.
Test 224 in xfstests hammers on this nicely, and with 1000 writers
trying to fill a 1GB drive we get our first ENOSPC at 93% full. The
other writers are able to continue until we get 100%.
This is a worst case test for btrfs because the 1000 writers are doing
small IO, and the small FS size means we don't have a lot of room
for metadata chunks.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
Btrfs: fix fiemap bugs with delalloc
Btrfs: set FMODE_EXCL in btrfs_device->mode
Btrfs: make btrfs_rm_device() fail gracefully
Btrfs: Avoid accessing unmapped kernel address
Btrfs: Fix BTRFS_IOC_SUBVOL_SETFLAGS ioctl
Btrfs: allow balance to explicitly allocate chunks as it relocates
Btrfs: put ENOSPC debugging under a mount option
Btrfs device shrinking and balancing ends up reallocating all the blocks
in order to allow COW to move them to new destinations. It is somewhat
awkward in terms of ENOSPC because most of the enospc code is built
around the idea that some operation on a reference counted tree triggers
allocations in the non-reference counted trees.
This commit changes the balancing code to deal with enospc by trying to
allocate a new chunk. If that allocation succeeds, we go ahead and
retry whatever failed due to enospc.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
ENOSPC in btrfs is getting to the point where the extra debugging isn't
required. I've put it under mount -o enospc_debug just in case someone
is having difficult problems.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
I add the check on the return value of alloc_extent_map() to several places.
In addition, alloc_extent_map() returns only the address or NULL.
Therefore, check by IS_ERR() is unnecessary. So, I remove IS_ERR() checking.
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: (33 commits)
Btrfs: Fix page count calculation
btrfs: Drop __exit attribute on btrfs_exit_compress
btrfs: cleanup error handling in btrfs_unlink_inode()
Btrfs: exclude super blocks when we read in block groups
Btrfs: make sure search_bitmap finds something in remove_from_bitmap
btrfs: fix return value check of btrfs_start_transaction()
btrfs: checking NULL or not in some functions
Btrfs: avoid uninit variable warnings in ordered-data.c
Btrfs: catch errors from btrfs_sync_log
Btrfs: make shrink_delalloc a little friendlier
Btrfs: handle no memory properly in prepare_pages
Btrfs: do error checking in btrfs_del_csums
Btrfs: use the global block reserve if we cannot reserve space
Btrfs: do not release more reserved bytes to the global_block_rsv than we need
Btrfs: fix check_path_shared so it returns the right value
btrfs: check return value of btrfs_start_ioctl_transaction() properly
btrfs: fix return value check of btrfs_join_transaction()
fs/btrfs/inode.c: Add missing IS_ERR test
btrfs: fix missing break in switch phrase
btrfs: fix several uncheck memory allocations
...
This has been resulting in a BUT_ON(ret) after btrfs_reserve_extent in
btrfs_cow_file_range. The reason is we don't actually calculate the bytes_super
for a block group until we go to cache it, which means that the space_info can
hand out reservations for space that it doesn't actually have, and we can run
out of data space. This is also a problem if you are using space caching since
we don't ever calculate bytes_super for the block groups. So instead everytime
we read a block group call exclude_super_stripes, which calculates the
bytes_super for the block group so it can be left out of the space_info. Then
whenever caching completes we just call free_excluded_extents so that the super
excluded extents are freed up. Also if we are unmounting and we hit any block
groups that haven't been cached we still need to call free_excluded_extents to
make sure things are cleaned up properly. Thanks,
Reported-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
The error check of btrfs_start_transaction() is added, and the mistake
of the error check on several places is corrected.
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Because NULL is returned when the memory allocation fails,
it is checked whether it is NULL.
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Xfstests 224 will just sit there and spin for ever until eventually we give up
flushing delalloc and exit. On my box this took several hours. I could not
interrupt this process either, even though we use INTERRUPTIBLE. So do 2 things
1) Keep us from looping over and over again without reclaiming anything
2) If we get interrupted exit the loop
I tested this and the test now exits in a reasonable amount of time, and can be
interrupted with ctrl+c. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
We call use_block_rsv right before we make an allocation in order to make sure
we have enough space. Now normally people have called btrfs_start_transaction()
with the appropriate amount of space that we need, so we just use some of that
pre-reserved space and move along happily. The problem is where people use
btrfs_join_transaction(), which doesn't actually reserve any space. So we try
and reserve space here, but we cannot flush delalloc, so this forces us to
return -ENOSPC when in reality we have plenty of space. The most common symptom
is seeing a bunch of "couldn't dirty inode" messages in syslog. With
xfstests 224 we end up falling back to start_transaction and then doing all the
flush delalloc stuff which causes to hang for a very long time.
So instead steal from the global reserve, which is what this is meant for
anyway. With this patch and the other 2 I have sent xfstests 224 now passes
successfully. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
When we do btrfs_block_rsv_release, if global_block_rsv is not full we will
release all the extra bytes to global_block_rsv, even if it's only a little
short of the amount of space that we need to reserve. This causes us to starve
ourselves of reservable space during the transaction which will force us to
shrink delalloc bytes and commit the transaction more often than we should. So
instead just add the amount of bytes we need to add to the global reserve so
reserved == size, and then add the rest back into the space_info for general
use. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
The error check of btrfs_join_transaction()/btrfs_join_transaction_nolock()
is added, and the mistake of the error check in several places is
corrected.
For more stable Btrfs, I think that we should reduce BUG_ON().
But, I think that long time is necessary for this.
So, I propose this patch as a short-term solution.
With this patch:
- To more stable Btrfs, the part that should be corrected is clarified.
- The panic isn't done by the NULL pointer reference etc. (even if
BUG_ON() is increased temporarily)
- The error code is returned in the place where the error can be easily
returned.
As a long-term plan:
- BUG_ON() is reduced by using the forced-readonly framework, etc.
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: (25 commits)
Btrfs: forced readonly mounts on errors
btrfs: Require CAP_SYS_ADMIN for filesystem rebalance
Btrfs: don't warn if we get ENOSPC in btrfs_block_rsv_check
btrfs: Fix memory leak in btrfs_read_fs_root_no_radix()
btrfs: check NULL or not
btrfs: Don't pass NULL ptr to func that may deref it.
btrfs: mount failure return value fix
btrfs: Mem leak in btrfs_get_acl()
btrfs: fix wrong free space information of btrfs
btrfs: make the chunk allocator utilize the devices better
btrfs: restructure find_free_dev_extent()
btrfs: fix wrong calculation of stripe size
btrfs: try to reclaim some space when chunk allocation fails
btrfs: fix wrong data space statistics
fs/btrfs: Fix build of ctree
Btrfs: fix off by one while setting block groups readonly
Btrfs: Add BTRFS_IOC_SUBVOL_GETFLAGS/SETFLAGS ioctls
Btrfs: Add readonly snapshots support
Btrfs: Refactor btrfs_ioctl_snap_create()
btrfs: Extract duplicate decompress code
...
This patch comes from "Forced readonly mounts on errors" ideas.
As we know, this is the first step in being more fault tolerant of disk
corruptions instead of just using BUG() statements.
The major content:
- add a framework for generating errors that should result in filesystems
going readonly.
- keep FS state in disk super block.
- make sure that all of resource will be freed and released at umount time.
- make sure that fter FS is forced readonly on error, there will be no more
disk change before FS is corrected. For this, we should stop write operation.
After this patch is applied, the conversion from BUG() to such a framework can
happen incrementally.
Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
If we run low on space we could get a bunch of warnings out of
btrfs_block_rsv_check, but this is mostly just called via the transaction code
to see if we need to end the transaction, it expects to see failures, so let's
not WARN and freak everybody out for no reason. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
When we store data by raid profile in btrfs with two or more different size
disks, df command shows there is some free space in the filesystem, but the
user can not write any data in fact, df command shows the wrong free space
information of btrfs.
# mkfs.btrfs -d raid1 /dev/sda9 /dev/sda10
# btrfs-show
Label: none uuid: a95cd49e-6e33-45b8-8741-a36153ce4b64
Total devices 2 FS bytes used 28.00KB
devid 1 size 5.01GB used 2.03GB path /dev/sda9
devid 2 size 10.00GB used 2.01GB path /dev/sda10
# btrfs device scan /dev/sda9 /dev/sda10
# mount /dev/sda9 /mnt
# dd if=/dev/zero of=tmpfile0 bs=4K count=9999999999
(fill the filesystem)
# sync
# df -TH
Filesystem Type Size Used Avail Use% Mounted on
/dev/sda9 btrfs 17G 8.6G 5.4G 62% /mnt
# btrfs-show
Label: none uuid: a95cd49e-6e33-45b8-8741-a36153ce4b64
Total devices 2 FS bytes used 3.99GB
devid 1 size 5.01GB used 5.01GB path /dev/sda9
devid 2 size 10.00GB used 4.99GB path /dev/sda10
It is because btrfs cannot allocate chunks when one of the pairing disks has
no space, the free space on the other disks can not be used for ever, and should
be subtracted from the total space, but btrfs doesn't subtract this space from
the total. It is strange to the user.
This patch fixes it by calcing the free space that can be used to allocate
chunks.
Implementation:
1. get all the devices free space, and align them by stripe length.
2. sort the devices by the free space.
3. check the free space of the devices,
3.1. if it is not zero, and then check the number of the devices that has
more free space than this device,
if the number of the devices is beyond the min stripe number, the free
space can be used, and add into total free space.
if the number of the devices is below the min stripe number, we can not
use the free space, the check ends.
3.2. if the free space is zero, check the next devices, goto 3.1
This implementation is just likely fake chunk allocation.
After appling this patch, df can show correct space information:
# df -TH
Filesystem Type Size Used Avail Use% Mounted on
/dev/sda9 btrfs 17G 8.6G 0 100% /mnt
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
- make it return the start position and length of the max free space when it can
not find a suitable free space.
- make it more readability
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
We cannot write data into files when when there is tiny space in the filesystem.
Reproduce steps:
# mkfs.btrfs /dev/sda1
# mount /dev/sda1 /mnt
# dd if=/dev/zero of=/mnt/tmpfile0 bs=4K count=1
# dd if=/dev/zero of=/mnt/tmpfile1 bs=4K count=99999999999999
(fill the filesystem)
# umount /mnt
# mount /dev/sda1 /mnt
# rm -f /mnt/tmpfile0
# dd if=/dev/zero of=/mnt/tmpfile0 bs=4K count=1
(failed with nospec)
But if we do the last step again, we can write data successfully. The reason of
the problem is that btrfs didn't try to commit the current transaction and
reclaim some space when chunk allocation failed.
This patch fixes it by committing the current transaction to reclaim some
space when chunk allocation fails.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
When we read in block groups, we'll set non-redundant groups
readonly if we find a raid1, DUP or raid10 group. But the
ro code has an off by one bug in the math around testing to
make sure out accounting doesn't go wrong.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
Btrfs: prevent RAID level downgrades when space is low
Btrfs: account for missing devices in RAID allocation profiles
Btrfs: EIO when we fail to read tree roots
Btrfs: fix compiler warnings
Btrfs: Make async snapshot ioctl more generic
Btrfs: pwrite blocked when writing from the mmaped buffer of the same page
Btrfs: Fix a crash when mounting a subvolume
Btrfs: fix sync subvol/snapshot creation
Btrfs: Fix page leak in compressed writeback path
Btrfs: do not BUG if we fail to remove the orphan item for dead snapshots
Btrfs: fixup return code for btrfs_del_orphan_item
Btrfs: do not do fast caching if we are allocating blocks for tree_root
Btrfs: deal with space cache errors better
Btrfs: fix use after free in O_DIRECT
The extent allocator has code that allows us to fill
allocations from any available block group, even if it doesn't
match the raid level we've requested.
This was put in because adding a new drive to a filesystem
made with the default mkfs options actually upgrades the metadata from
single spindle dup to full RAID1.
But, the code also allows us to allocate from a raid0 chunk when we
really want a raid1 or raid10 chunk. This can cause big trouble because
mkfs creates a small (4MB) raid0 chunk for data and metadata which then
goes unused for raid1/raid10 installs.
The allocator will happily wander in and allocate from that chunk when
things get tight, which is not correct.
The fix here is to make sure that we provide duplication when the
caller has asked for it. It does all the dups to be any raid level,
which preserves the dup->raid1 upgrade abilities.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
When we mount in RAID degraded mode without adding a new device to
replace the failed one, we can end up using the wrong RAID flags for
allocations.
This results in strange combinations of block groups (raid1 in a raid10
filesystem) and corruptions when we try to allocate blocks from single
spindle chunks on drives that are actually missing.
The first device has two small 4MB chunks in it that mkfs creates and
these are usually unused in a raid1 or raid10 setup. But, in -o degraded,
the allocator will fall back to these because the mask of desired raid groups
isn't correct.
The fix here is to count the missing devices as we build up the list
of devices in the system. This count is used when picking the
raid level to make sure we continue using the same levels that were
in place before we lost a drive.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Not being able to delete an orphan item isn't a horrible thing. The worst that
happens is the next time around we try and do the orphan cleanup and we can't
find the referenced object and just delete the item and move on.
Signed-off-by: Josef Bacik <josef@redhat.com>
Since the fast caching uses normal tree locking, we can possibly deadlock if we
get to the caching via a btrfs_search_slot() on the tree_root. So just check to
see if the root we are on is the tree root, and just don't do the fast caching.
Reported-by: Sage Weil <sage@newdream.net>
Signed-off-by: Josef Bacik <josef@redhat.com>
Currently if the space cache inode generation number doesn't match the
generation number in the space cache header we will just fail to load the space
cache, but we won't mark the space cache as an error, so we'll keep getting that
error each time somebody tries to cache that block group until we actually clear
the thing. Fix this by marking the space cache as having an error so we only
get the message once. This patch also makes it so that we don't try and setup
space cache for a block group that isn't cached, since we won't be able to write
it out anyway. None of these problems are actual problems, they are just
annoying and sub-optimal. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: (24 commits)
Btrfs: don't use migrate page without CONFIG_MIGRATION
Btrfs: deal with DIO bios that span more than one ordered extent
Btrfs: setup blank root and fs_info for mount time
Btrfs: fix fiemap
Btrfs - fix race between btrfs_get_sb() and umount
Btrfs: update inode ctime when using links
Btrfs: make sure new inode size is ok in fallocate
Btrfs: fix typo in fallocate to make it honor actual size
Btrfs: avoid NULL pointer deref in try_release_extent_buffer
Btrfs: make btrfs_add_nondir take parent inode as an argument
Btrfs: hold i_mutex when calling btrfs_log_dentry_safe
Btrfs: use dget_parent where we can UPDATED
Btrfs: fix more ESTALE problems with NFS
Btrfs: handle NFS lookups properly
btrfs: make 1-bit signed fileds unsigned
btrfs: Show device attr correctly for symlinks
btrfs: Set file size correctly in file clone
btrfs: Check if dest_offset is block-size aligned before cloning file
Btrfs: handle the space_cache option properly
btrfs: Fix early enospc because 'unused' calculated with wrong sign.
...
'unused' calculated with wrong sign in reserve_metadata_bytes().
This might have lead to unwanted over-reservations.
Signed-off-by: Arne Jansen <sensille@gmx.net>
Reviewed-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: (39 commits)
Btrfs: deal with errors from updating the tree log
Btrfs: allow subvol deletion by unprivileged user with -o user_subvol_rm_allowed
Btrfs: make SNAP_DESTROY async
Btrfs: add SNAP_CREATE_ASYNC ioctl
Btrfs: add START_SYNC, WAIT_SYNC ioctls
Btrfs: async transaction commit
Btrfs: fix deadlock in btrfs_commit_transaction
Btrfs: fix lockdep warning on clone ioctl
Btrfs: fix clone ioctl where range is adjacent to extent
Btrfs: fix delalloc checks in clone ioctl
Btrfs: drop unused variable in block_alloc_rsv
Btrfs: cleanup warnings from gcc 4.6 (nonbugs)
Btrfs: Fix variables set but not read (bugs found by gcc 4.6)
Btrfs: Use ERR_CAST helpers
Btrfs: use memdup_user helpers
Btrfs: fix raid code for removing missing drives
Btrfs: Switch the extent buffer rbtree into a radix tree
Btrfs: restructure try_release_extent_buffer()
Btrfs: use the flusher threads for delalloc throttling
Btrfs: tune the chunk allocation to 5% of the FS as metadata
...
Fix up trivial conflicts in fs/btrfs/super.c and fs/fs-writeback.c, and
remove use of INIT_RCU_HEAD in fs/btrfs/extent_io.c (that init macro was
useless and removed in commit 5e8067adfdba: "rcu head remove init")
These are all the cases where a variable is set, but not read which are
not bugs as far as I can see, but simply leftovers.
Still needs more review.
Found by gcc 4.6's new warnings
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
We have a fairly complex set of loops around walking our list of
delalloc inodes when we find metadata delalloc space running low.
It doesn't work very well, can use large amounts of CPU and doesn't
do very efficient writeback.
This switches us to kick the bdi flusher threads instead. All dirty
data in btrfs is accounted as delalloc data, so this is very similar
in terms of what it writes, but we're able to just kick off the IO
and wait for progress.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
An earlier commit tried to keep us from allocating too many
empty metadata chunks. It was somewhat too restrictive and could
lead to ENOSPC errors on empty filesystems.
This increases the limits to about 5% of the FS size, allowing more
metadata chunks to be preallocated.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
If you mount -o space_cache, the option will be persistent across mounts, but to
make sure the user knows that they did this, emit a message telling them if they
didn't mount with -o space_cache but the feature is still used.
Signed-off-by: Josef Bacik <josef@redhat.com>
If something goes wrong with the free space cache we need a way to make sure
it's not loaded on mount and that it's cleared for everybody. When you pass the
clear_cache option it will make it so all block groups are setup to be cleared,
which keeps them from being loaded and then they will be truncated when the
transaction is committed. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
There are just a few things that need to be fixed in the kernel to support mixed
data+metadata block groups. Mostly we just need to make sure that if we are
using mixed block groups that we continue to allocate mixed block groups as we
need them. Also we need to make sure __find_space_info will find our space info
if we search for DATA or METADATA only. Tested this with xfstests and it works
nicely. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
With the free space disk caching we can mark the block group as started with the
caching, but we don't have a caching ctl. This can race with anybody else who
tries to get the caching ctl before we cache (this is very hard to do btw). So
instead check to see if cache->caching_ctl is set, and if not return NULL.
Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
This patch actually loads the free space cache if it exists. The only thing
that really changes here is that we need to cache the block group if we're going
to remove an extent from it. Previously we did not do this since the caching
kthread would pick it up. With the on disk cache we don't have this luxury so
we need to make sure we read the on disk cache in first, and then remove the
extent, that way when the extent is unpinned the free space is added to the
block group. This has been tested with all sorts of things.
Signed-off-by: Josef Bacik <josef@redhat.com>
This is a simple bit, just dump the free space cache out to our preallocated
inode when we're writing out dirty block groups. There are a bunch of changes
in inode.c in order to account for special cases. Mostly when we're doing the
writeout we're holding trans_mutex, so we need to use the nolock transacation
functions. Also we can't do asynchronous completions since the async thread
could be blocked on already completed IO waiting for the transaction lock. This
has been tested with xfstests and btrfs filesystem balance, as well as my ENOSPC
tests. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
In order to save free space cache, we need an inode to hold the data, and we
need a special item to point at the right inode for the right block group. So
first, create a special item that will point to the right inode, and the number
of extent entries we will have and the number of bitmaps we will have. We
truncate and pre-allocate space everytime to make sure it's uptodate.
This feature will be turned on as soon as you mount with -o space_cache, however
it is safe to boot into old kernels, they will just generate the cache the old
fashion way. When you boot back into a newer kernel we will notice that we
modified and not the cache and automatically discard the cache.
Signed-off-by: Josef Bacik <josef@redhat.com>
Because btrfs_dirty_inode does a btrfs_join_transaction, it doesn't actually
reserve space. It does this so we can try and dirty the inode quickly without
having to deal with the ENOSPC problems. But if it does get back ENOSPC it
handles it properly. The problem is use_block_rsv does a WARN_ON whenever this
case happens, even tho btrfs_dirty_inode takes it into account and actually
expects to get -ENOSPC if things are particularly tight. So instead just remove
the warning. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
btrfs_commit_transaction will free our trans, but because we pass trans to
shrink_delalloc we could possibly have a use after free situation. So instead
if we commit the transaction, set trans to null and set committed to true so we
don't keep trying to commit a transaction. This fixes a panic I could reproduce
at will. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
With multi-threaded writes we were getting ENOSPC early because somebody would
come in, start flushing delalloc because they couldn't make their reservation,
and in the meantime other threads would come in and use the space that was
getting freed up, so when the original thread went to check to see if they had
space they didn't and they'd return ENOSPC. So instead if we have some free
space but not enough for our reservation, take the reservation and then start
doing the flushing. The only time we don't take reservations is when we've
already overcommitted our space, that way we don't have people who come late to
the party way overcommitting ourselves. This also moves all of the retrying and
flushing code into reserve_metdata_bytes so it's all uniform. This keeps my
fs_mark test from returning -ENOSPC as soon as it starts and actually lets me
fill up the disk. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Because the ENOSPC code over reserves super aggressively we end up allocating
chunks way more often than we should. For example with my fs_mark tests on a
2gb fs I can end up reserved 1gb just for metadata, when only 34mb of that is
being used. So instead check to see if the amount of space actually used is
less than 30% of the total space, and if so don't allocate a chunk, but only if
we have at least 256mb of free space to make sure we don't put too much pressure
on free space.
Signed-off-by: Josef Bacik <josef@redhat.com>
Currently we try and flush delalloc, but we only do that in a sort of weak way,
which works fine in most cases but if we're under heavy pressure we need to be
able to wait for flushing to happen. Also instead of checking the bytes
reserved in the block_rsv, check the space info since it is more accurate. The
sync option will be used in a future patch.
Signed-off-by: Josef Bacik <josef@redhat.com>
The global reservation stuff tries to add together DATA and METADATA used in
order to figure out how much to reserve for everything, but this doesn't work
right for mixed block groups. Instead if we have mixed block groups just set
data used to 0. Also with mixed block groups we will use bytes_may_use for
keeping track of delalloc bytes, so we need to take that into account in our
reservation calculations.
Signed-off-by: Josef Bacik <josef@redhat.com>
The new ENOSPC stuff breaks out the raid types which breaks the way we were
reporting df to the system. This fixes it back so that Available is the total
space available to data and used is the actual bytes used by the filesystem.
This means that Available is Total - data used - all of the metadata space.
Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
In very severe ENOSPC cases we can run out of inodes to do delalloc on, which
means we'll just keep looping trying to shrink delalloc. Instead, if we fail to
shrink delalloc 3 times in a row break out since we're not likely to make any
progress. Tested this with a 100mb fs an xfstests test 13. Before the patch it
would hang the box, with the patch we get -ENOSPC like we should. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
All the blkdev_issue_* helpers can only sanely be used for synchronous
caller. To issue cache flushes or barriers asynchronously the caller needs
to set up a bio by itself with a completion callback to move the asynchronous
state machine ahead. So drop the BLKDEV_IFL_WAIT flag that is always
specified when calling blkdev_issue_* and also remove the now unused flags
argument to blkdev_issue_flush and blkdev_issue_zeroout. For
blkdev_issue_discard we need to keep it for the secure discard flag, which
gains a more descriptive name and loses the bitops vs flag confusion.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Switch to the WRITE_FLUSH_FUA flag for log writes, remove the EOPNOTSUPP
detection for barriers and stop setting the barrier flag for discards.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
Btrfs: The file argument for fsync() is never null
Btrfs: handle ERR_PTR from posix_acl_from_xattr()
Btrfs: avoid BUG when dropping root and reference in same transaction
Btrfs: prohibit a operation of changing acl's mask when noacl mount option used
Btrfs: should add a permission check for setfacl
Btrfs: btrfs_lookup_dir_item() can return ERR_PTR
Btrfs: btrfs_read_fs_root_no_name() returns ERR_PTRs
Btrfs: unwind after btrfs_start_transaction() errors
Btrfs: btrfs_iget() returns ERR_PTR
Btrfs: handle kzalloc() failure in open_ctree()
Btrfs: handle error returns from btrfs_lookup_dir_item()
Btrfs: Fix BUG_ON for fs converted from extN
Btrfs: Fix null dereference in relocation.c
Btrfs: fix remap_file_pages error
Btrfs: uninitialized data is check_path_shared()
Btrfs: fix fallocate regression
Btrfs: fix loop device on top of btrfs
Tree blocks can live in data block groups in FS converted from extN.
So it's easy to trigger the BUG_ON.
Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: (27 commits)
Btrfs: add more error checking to btrfs_dirty_inode
Btrfs: allow unaligned DIO
Btrfs: drop verbose enospc printk
Btrfs: Fix block generation verification race
Btrfs: fix preallocation and nodatacow checks in O_DIRECT
Btrfs: avoid ENOSPC errors in btrfs_dirty_inode
Btrfs: move O_DIRECT space reservation to btrfs_direct_IO
Btrfs: rework O_DIRECT enospc handling
Btrfs: use async helpers for DIO write checksumming
Btrfs: don't walk around with task->state != TASK_RUNNING
Btrfs: do aio_write instead of write
Btrfs: add basic DIO read/write support
direct-io: do not merge logically non-contiguous requests
direct-io: add a hook for the fs to provide its own submit_bio function
fs: allow short direct-io reads to be completed via buffered IO
Btrfs: Metadata ENOSPC handling for balance
Btrfs: Pre-allocate space for data relocation
Btrfs: Metadata ENOSPC handling for tree log
Btrfs: Metadata reservation for orphan inodes
Btrfs: Introduce global metadata reservation
...
This patch adds metadata ENOSPC handling for the balance code.
It is consisted by following major changes:
1. Avoid COW tree leave in the phrase of merging tree.
2. Handle interaction with snapshot creation.
3. make the backref cache can live across transactions.
Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Reserve metadata space for extent tree, checksum tree and root tree
Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Introduce metadata reservation context for delayed allocation
and update various related functions.
This patch also introduces EXTENT_FIRST_DELALLOC control bit for
set/clear_extent_bit. It tells set/clear_bit_hook whether they
are processing the first extent_state with EXTENT_DELALLOC bit
set. This change is important if set/clear_extent_bit involves
multiple extent_state.
Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Besides simplify the code, this change makes sure all metadata
reservation for normal metadata operations are released after
committing transaction.
Changes since V1:
Add code that check if unlink and rmdir will free space.
Add ENOSPC handling for clone ioctl.
Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Introducing metadata reseravtion contexts has two major advantages.
First, it makes metadata reseravtion more traceable. Second, it can
reclaim freed space and re-add them to the itself after transaction
committed.
Besides add btrfs_block_rsv structure and related helper functions,
This patch contains following changes:
Move code that decides if freed tree block should be pinned into
btrfs_free_tree_block().
Make space accounting more accurate, mainly for handling read only
block groups.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Shrink delayed allocation space in a synchronized manner is more
controllable than flushing all delay allocated space in an async
thread.
Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
We already have fs_info->chunk_mutex to avoid concurrent
chunk creation.
Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
The size of reserved space is stored in space_info. If block groups
of different raid types are linked to separate space_info, changing
allocation profile will corrupt reserved space accounting.
Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
The patch just convert all blkdev_issue_xxx function to common
set of flags. Wait/allocation semantics preserved.
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
Btrfs: make sure the chunk allocator doesn't create zero length chunks
Btrfs: fix data enospc check overflow
* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
Btrfs: add check for changed leaves in setup_leaf_for_split
Btrfs: create snapshot references in same commit as snapshot
Btrfs: fix small race with delalloc flushing waitqueue's
Btrfs: use add_to_page_cache_lru, use __page_cache_alloc
Btrfs: fix chunk allocate size calculation
Btrfs: kill max_extent mount option
Btrfs: fail to mount if we have problems reading the block groups
Btrfs: check btrfs_get_extent return for IS_ERR()
Btrfs: handle kmalloc() failure in inode lookup ioctl
Btrfs: dereferencing freed memory
Btrfs: Simplify num_stripes's calculation logical for __btrfs_alloc_chunk()
Btrfs: Add error handle for btrfs_search_slot() in btrfs_read_chunk_tree()
Btrfs: Remove unnecessary finish_wait() in wait_current_trans()
Btrfs: add NULL check for do_walk_down()
Btrfs: remove duplicate include in ioctl.c
Fix trivial conflict in fs/btrfs/compression.c due to slab.h include
cleanups.
Because we account for reserved space we get from the allocator before we
actually account for allocating delalloc space, we can have a small window where
the amount of "used" space in a space_info is more than the total amount of
space in the space_info. This will cause a overflow in our check, so it will
seem like we have _tons_ of free space, and we'll allow reservations to occur
that will end up larger than the amount of space we have. I've seen users
report ENOSPC panic's in cow_file_range a few times recently, so I tried to
reproduce this problem and found I could reproduce it if I ran one of my tests
in a loop for like 20 minutes. With this patch my test ran all night without
issues. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Everytime we start a new flushing thread, we init the waitqueue if there isn't a
flushing thread running. The problem with this is we check
space_info->flushing, which we clear right before doing a wake_up on the
flushing waitqueue, which causes problems if we init the waitqueue in the middle
of clearing the flushing flagh and calling wake_up. This is hard to hit, but
the code is wrong anyway, so init the flushing/allocating waitqueue when
creating the space info and let it be. I haven't seen the panic since I've been
using this patch. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
As Yan pointed out, theres not much reason for all this complicated math to
account for file extents being split up into max_extent chunks, since they are
likely to all end up in the same leaf anyway. Since there isn't much reason to
use max_extent, just remove the option altogether so we have one less thing we
need to test.
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
We don't actually check the return value of btrfs_read_block_groups, so we can
possibly succeed to mount, but then fail to say read the superblock xattr for
selinux which will cause the vfs code to deactivate the super.
This is a problem because in find_free_extent we just assume that we
will find the right space_info for the allocation we want. But if we
failed to read the block groups, we won't have setup any space_info's,
and we'll hit a NULL pointer deref in find_free_extent.
This patch fixes that problem by checking the return value of
btrfs_read_block_groups, and failing out properly. I've also added a
check in find_free_extent so if for some reason we don't find an
appropriate space_info, we just return -ENOSPC.
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
btrfs_find_create_tree_block() may return NULL, so we must check the returned
value, or we will access a NULL pointer.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
This patch just goes through and fixes everybody that does
lock_extent()
blah
unlock_extent()
to use
lock_extent_bits()
blah
unlock_extent_cached()
and pass around a extent_state so we only have to do the searches once per
function. This gives me about a 3 mb/s boots on my random write test. I have
not converted some things, like the relocation and ioctl's, since they aren't
heavily used and the relocation stuff is in the middle of being re-written. I
also changed the clear_extent_bit() to only unset the cached state if we are
clearing EXTENT_LOCKED and related stuff, so we can do things like this
lock_extent_bits()
clear delalloc bits
unlock_extent_cached()
without losing our cached state. I tested this thoroughly and turned on
LEAK_DEBUG to make sure we weren't leaking extent states, everything worked out
fine.
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
When dropping a empty tree, walk_down_tree() skips checking
extent information for the tree root. This will triggers a
BUG_ON in walk_up_proc().
Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Josef Bacik