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>
Extract out block group specific code from lookup_free_space_inode(),
create_free_space_inode(), load_free_space_cache() and
btrfs_write_out_cache(), so the code can be used to read/write
free ino cache.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Currently btrfs stores the highest objectid of the fs tree, and it always
returns (highest+1) inode number when we create a file, so inode numbers
won't be reclaimed when we delete files, so we'll run out of inode numbers
as we keep create/delete files in 32bits machines.
This fixes it, and it works similarly to how we cache free space in block
cgroups.
We start a kernel thread to read the file tree. By scanning inode items,
we know which chunks of inode numbers are free, and we cache them in
an rb-tree.
Because we are searching the commit root, we have to carefully handle the
cross-transaction case.
The rb-tree is a hybrid extent+bitmap tree, so if we have too many small
chunks of inode numbers, we'll use bitmaps. Initially we allow 16K ram
of extents, and a bitmap will be used if we exceed this threshold. The
extents threshold is adjusted in runtime.
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>
The free space caching code was recently reworked to
cache all the pages it needed instead of using find_get_page everywhere.
One loop was missed though, so it ended up leaking pages. This fixes
it to use our page array instead of find_get_page.
Signed-off-by: Chris Mason <chris.mason@oracle.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>
A recent commit caches the extent state in end_bio_extent_readpage,
but the search it does should look for locked extents. This
fixes things to make it more effective.
Signed-off-by: Chris Mason <chris.mason@oracle.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>
Call posix_acl_valid() to check if an acl is valid or not.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Link count of the inode is not decreased if btrfs_set_inode_index()
fails.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Singed-off-by: Li Zefan <lizf@cn.fujitsu.com>
btrfs_next_leaf() can return -errno, and we should propagate
it to userspace.
This also simplifies how we walk the btree path.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
btrfs_next_leaf() can return -errno, and we should propagate
it to userspace.
This also simplifies how we walk the btree path.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
The extent_io code can take cached pointers into the extent state trees,
and these can make lookups much faster in common operations. The
caching only happens when specific bits are set that prevent merging
and splitting of the extent state.
A help function was added to uncache the state, and it was testing
the same set of conditionals. This can leak in very strange corner
cases where the lock bit goes away unexpectedly.
The uncaching should be unconditional. Once we have a ref on the
extent we should always give it up.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
In several places the sequence (set_extent_uptodate, unlock_extent) is used.
This leads to a duplicate lookup of the extent state. This patch lets
set_extent_uptodate return a cached extent_state which can be passed to
unlock_extent_cached.
The occurences of the above sequences are updated to use the cache. Only
end_bio_extent_readpage is updated that it first gets a cached state to
pass it to the readpage_end_io_hook as the prototype requested and is later
on being used for set/unlock.
Signed-off-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
I've been working on making our O_DIRECT latency not suck and I noticed we were
taking the trans_mutex in btrfs_end_transaction. So to do this we convert
num_writers and use_count to atomic_t's and just decrement them in
btrfs_end_transaction. Instead of deleting the transaction from the trans list
in put_transaction we do that in btrfs_commit_transaction() since that's the
only time it actually needs to be removed from the list. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
We create two subvolumes (meego_root and meego_home) in
btrfs root directory. And set meego_root as default mount
subvolume. After we remount btrfs, meego_root is mounted
to top directory by default. Then when we try to mount
meego_home (subvol=meego_home) to a subdirectory, it failed.
The problem is when default mount subvolume is set to
meego_root, we search meego_home in meego_root but can not find
it. So the solution is to add a new mount option (subvolrootid)
to specify subvol id of root and search subvol name in it. For
our case, now we can use "-o subvolrootid=0,subvol=meego_home)
to mount meego_home.
Detail information can be found in meego bugzilla:
https://bugs.meego.com/show_bug.cgi?id=15055
Signed-off-by: Zhong, Xin <xin.zhong@intel.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Apparently it is ok to submit a read to an IDE device with the same target page
for different offsets. This is what Windows does under qemu. The problem is
under DIO we expect them to be different buffers for checksumming reasons, and
so this sort of thing will result in checksum errors, when in reality the file
is fine. So when reading, check to make sure that all iov bases are different,
and if they aren't fall back to buffered mode, since that will work out right.
Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
This patch fixes memory leaks in btrfs_new_inode().
Signed-off-by: Yoshinori Sano <yoshinori.sano@gmail.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Apparently it is ok to submit a read to an IDE device with the same target page
for different offsets. This is what Windows does under qemu. The problem is
under DIO we expect them to be different buffers for checksumming reasons, and
so this sort of thing will result in checksum errors, when in reality the file
is fine. So when reading, check to make sure that all iov bases are different,
and if they aren't fall back to buffered mode, since that will work out right.
Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
In btrfs_get_block_direct we call btrfs_get_extent to lookup the extent for the
range that we are looking for. If we don't find an extent, btrfs_get_extent
will insert a extent_map for that area and mark it as a hole. So it does the
job of allocating a new extent map and inserting it into the io tree. But if
we're creating a new extent we free it up and redo all of that work. So instead
pass the em to btrfs_new_extent_direct(), and if it will work just allocate the
disk space and set it up properly and bypass the freeing/allocating of a new
extent map and the expensive operation of inserting the thing into the io_tree.
Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
When looking at our DIO performance Chris said that for small IO's doing the
async submit stuff tends to be more overhead than it's worth. With this on top
of my other fixes I get about a 17-20% speedup doing a sequential dd with 4k
IO's. Basically if we don't have to split the bio for the map length it's small
enough to be directly submitted, otherwise go back to the async submit. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
We have been unconditionally allocating a new bio and re-adding all pages from
our original bio to the new bio. This is needed if our original bio is larger
than our stripe size, but if it is smaller than the stripe size then there is no
need to do this. So check the map length and if we are under that then go ahead
and submit the original bio. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
In the DIO code we often don't update the i_disk_size because the i_size isn't
updated until after the DIO is completed, so basically we are allocating a path,
doing a search, and updating the inode item for no reason since nothing changed.
btrfs_ordered_update_i_size will return 1 if it didn't update i_disk_size, so
only run btrfs_update_inode if btrfs_ordered_update_i_size returns 0. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Instead of calling kmap_atomic for every thing we set in the inode item, map the
entire inode item at the start and unmap it at the end. This makes a sequential
dd of 400mb O_DIRECT something like 1% faster. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
I saw a lockup where we kept getting into this start transaction->commit
transaction loop because of enospce. The fact is if we fail to make our
reservation, we've tried _everything_ several times, so we only need to try and
commit the transaction once, and if that doesn't work then we really are out of
space and need to just exit. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Currently we don't handle running out of space in the cache, so to fix this we
keep track of how far in the cache we are. Then we only dirty the pages if we
successfully modify all of them, otherwise if we have an error or run out of
space we can just drop them and not worry about the vm writing them out.
Thanks,
Tested-by Johannes Hirte <johannes.hirte@fem.tu-ilmenau.de>
Signed-off-by: Josef Bacik <josef@redhat.com>
When I moved the orphan adding to btrfs_truncate I missed the fact that during
orphan cleanup we just add the orphan items to the orphan list without going
through btrfs_orphan_add, which results in lots of warnings on mount if you have
any orphan items that need to be truncated. Just remove this warning since it's
ok, this will allow all of the normal space accounting take place. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
I noticed a huge problem with the free space cache that was presenting
as an early ENOSPC. Turns out when writing the free space cache out I
forgot to take into account pinned extents and more importantly
clusters. This would result in us leaking free space everytime we
unmounted the filesystem and remounted it.
I fix this by making sure to check and see if the current block group
has a cluster and writing out any entries that are in the cluster to the
cache, as well as writing any pinned extents we currently have to the
cache since those will be available for us to use the next time the fs
mounts.
This patch also adds a check to the end of load_free_space_cache to make
sure we got the right amount of free space cache, and if not make sure
to clear the cache and re-cache the old fashioned way.
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
root_item->flags and root_item->byte_limit are not initialized when
a subvolume is created. This bug is not revealed until we added
readonly snapshot support - now you mount a btrfs filesystem and you
may find the subvolumes in it are readonly.
To work around this problem, we steal a bit from root_item->inode_item->flags,
and use it to indicate if those fields have been properly initialized.
When we read a tree root from disk, we check if the bit is set, and if
not we'll set the flag and initialize the two fields of the root item.
Reported-by: Andreas Philipp <philipp.andreas@gmail.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Tested-by: Andreas Philipp <philipp.andreas@gmail.com>
cc: stable@kernel.org
Signed-off-by: Chris Mason <chris.mason@oracle.com>
the object id of the space cache inode's key is allocated from the relative
root, just like the regular file. So we can't identify space cache inode by
checking the object id of the inode's key, and we have to clear __GFP_FS flag
at the time we look up the space cache inode.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Free btrfs_trans_handle when join_transaction() fails
in start_transaction()
Signed-off-by: Yoshinori Sano <yoshinori.sano@gmail.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
btrfs_rename() does not release the subvol_sem if the transaction failed to start.
Signed-off-by: Johann Lombardi <johann@whamcloud.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
When we defrag a file, whose size can be fit into an inline extent,
with compression enabled, the compress type is set to be
fs_info->compress_type, which is 0 if the btrfs filesystem is mounted
without compress option. This leads to oops.
Reported-by: Daniel Blueman <daniel.blueman@gmail.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Some mount options are not displayed by /proc/mounts.
This patch displays the option such as compress_type by /proc/mounts.
Ex.
[before]
$ mount | grep sdc2
/dev/sdc2 on /test12 type btrfs (rw,space_cache,compress=lzo)
$ cat /proc/mounts | grep sdc2
/dev/sdc2 /test12 btrfs rw,relatime,compress 0 0
[after]
$ mount | grep sdc2
/dev/sdc2 on /test12 type btrfs (rw,space_cache,compress=lzo)
$ cat /proc/mounts | grep sdc2
/dev/sdc2 /test12 btrfs rw,relatime,compress=lzo,space_cache 0 0
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
While compiling Btrfs, I got following messages:
CC [M] fs/btrfs/file.o
fs/btrfs/file.c: In function '__btrfs_buffered_write':
fs/btrfs/file.c:909: warning: 'ret' may be used uninitialized in this function
CC [M] fs/btrfs/tree-defrag.o
This patch fixes compiler warning.
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Recent changes for discard support didn't compile,
this fixes them not to try and % 64 bit numbers.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Using the GFP_HIGHUSER_MOVABLE flag to allocate the metadata's page may cause
deadlock.
Task1
open()
...
btrfs_search_slot()
...
btrfs_cow_block()
...
alloc_page()
wait for reclaiming
shrink_slab()
...
shrink_icache_memory()
...
btrfs_evict_inode()
...
btrfs_search_slot()
If the path is locked by task1, the deadlock happens.
So the btree's page cache is different with the file's page cache, it can not
allocate pages by GFP_HIGHUSER_MOVABLE flag, we must clear __GFP_FS flag in
GFP_HIGHUSER_MOVABLE flag.
Reported-by: Itaru Kitayama <kitayama@cl.bb4u.ne.jp>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
old_inode is not locked; it's not safe to play with its link
count. Instead of bumping it and calling btrfs_unlink_inode(),
add a variant of the latter that does not do btrfs_drop_nlink()/
btrfs_update_inode(), call it instead of btrfs_inc_nlink()/
btrfs_unlink_inode() and do btrfs_update_inode() ourselves.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Adding the check on the return value of btrfs_alloc_path() to several places.
And, some of callers are modified by this change.
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
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>
setflags ioctl should return error when any checks fail.
Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
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>
