btrfs currently handles most errors with BUG_ON. This patch is a work-in-
progress but aims to handle most errors other than internal logic
errors and ENOMEM more gracefully.
This iteration prevents most crashes but can run into lockups with
the page lock on occasion when the timing "works out."
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
lock_extent and unlock_extent are always called with GFP_NOFS, drop the
argument and use GFP_NOFS consistently.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Pull trivial tree from Jiri Kosina:
"It's indeed trivial -- mostly documentation updates and a bunch of
typo fixes from Masanari.
There are also several linux/version.h include removals from Jesper."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (101 commits)
kcore: fix spelling in read_kcore() comment
constify struct pci_dev * in obvious cases
Revert "char: Fix typo in viotape.c"
init: fix wording error in mm_init comment
usb: gadget: Kconfig: fix typo for 'different'
Revert "power, max8998: Include linux/module.h just once in drivers/power/max8998_charger.c"
writeback: fix fn name in writeback_inodes_sb_nr_if_idle() comment header
writeback: fix typo in the writeback_control comment
Documentation: Fix multiple typo in Documentation
tpm_tis: fix tis_lock with respect to RCU
Revert "media: Fix typo in mixer_drv.c and hdmi_drv.c"
Doc: Update numastat.txt
qla4xxx: Add missing spaces to error messages
compiler.h: Fix typo
security: struct security_operations kerneldoc fix
Documentation: broken URL in libata.tmpl
Documentation: broken URL in filesystems.tmpl
mtd: simplify return logic in do_map_probe()
mm: fix comment typo of truncate_inode_pages_range
power: bq27x00: Fix typos in comment
...
Quoth Chris:
"This is later than I wanted because I got backed up running through
btrfs bugs from the Oracle QA teams. But they are all bug fixes that
we've queued and tested since rc1.
Nothing in particular stands out, this just reflects bug fixing and QA
done in parallel by all the btrfs developers. The most user visible
of these is:
Btrfs: clear the extent uptodate bits during parent transid failures
Because that helps deal with out of date drives (say an iscsi disk
that has gone away and come back). The old code wasn't always
properly retrying the other mirror for this type of failure."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (24 commits)
Btrfs: fix compiler warnings on 32 bit systems
Btrfs: increase the global block reserve estimates
Btrfs: clear the extent uptodate bits during parent transid failures
Btrfs: add extra sanity checks on the path names in btrfs_mksubvol
Btrfs: make sure we update latest_bdev
Btrfs: improve error handling for btrfs_insert_dir_item callers
Btrfs: be less strict on finding next node in clear_extent_bit
Btrfs: fix a bug on overcommit stuff
Btrfs: kick out redundant stuff in convert_extent_bit
Btrfs: skip states when they does not contain bits to clear
Btrfs: check return value of lookup_extent_mapping() correctly
Btrfs: fix deadlock on page lock when doing auto-defragment
Btrfs: fix return value check of extent_io_ops
btrfs: honor umask when creating subvol root
btrfs: silence warning in raid array setup
btrfs: fix structs where bitfields and spinlock/atomic share 8B word
btrfs: delalloc for page dirtied out-of-band in fixup worker
Btrfs: fix memory leak in load_free_space_cache()
btrfs: don't check DUP chunks twice
Btrfs: fix trim 0 bytes after a device delete
...
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: fix reservations in btrfs_page_mkwrite
Btrfs: advance window_start if we're using a bitmap
btrfs: mask out gfp flags in releasepage
Btrfs: fix enospc error caused by wrong checks of the chunk
Btrfs: do not defrag a file partially
Btrfs: fix warning for 32-bit build of fs/btrfs/check-integrity.c
Btrfs: use cluster->window_start when allocating from a cluster bitmap
Btrfs: Check for NULL page in extent_range_uptodate
btrfs: Fix busyloops in transaction waiting code
Btrfs: make sure a bitmap has enough bytes
Btrfs: fix uninit warning in backref.c
If we span a long area in a bitmap we could end up taking a lot of time
searching to the next free area if we're searching from the original
window_start, so advance window_start in order to make sure we don't do any
superficial searching. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
We specifically set window_start in the cluster struct to indicate where the
cluster starts in a bitmap, but we've been using min_start to indicate where
we're searching from. This is usually the start of the blockgroup, so
essentially means we're constantly searching from the start of any bitmap we
find, which completely negates all the trouble we go to in order to setup a
cluster. So start using window_start to make sure we actually use the area we
found. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
We have only been checking for min_bytes available in bitmap entries, but we
won't successfully setup a bitmap cluster unless it has at least bytes in the
bitmap, so in the common case min_bytes is 4k and we want something like 2MB, so
if there are a bunch of bitmap entries with less than 2mb's in them, we'll
search all them anyway, which is suboptimal. Fix this check. Thanks,
Signed-off-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/linux-btrfs: (62 commits)
Btrfs: use larger system chunks
Btrfs: add a delalloc mutex to inodes for delalloc reservations
Btrfs: space leak tracepoints
Btrfs: protect orphan block rsv with spin_lock
Btrfs: add allocator tracepoints
Btrfs: don't call btrfs_throttle in file write
Btrfs: release space on error in page_mkwrite
Btrfs: fix btrfsck error 400 when truncating a compressed
Btrfs: do not use btrfs_end_transaction_throttle everywhere
Btrfs: add balance progress reporting
Btrfs: allow for resuming restriper after it was paused
Btrfs: allow for canceling restriper
Btrfs: allow for pausing restriper
Btrfs: add skip_balance mount option
Btrfs: recover balance on mount
Btrfs: save balance parameters to disk
Btrfs: soft profile changing mode (aka soft convert)
Btrfs: implement online profile changing
Btrfs: do not reduce profile in do_chunk_alloc()
Btrfs: virtual address space subset filter
...
Fix up trivial conflict in fs/btrfs/ioctl.c due to the use of the new
mnt_drop_write_file() helper.
I used these tracepoints when figuring out what the cluster stuff was doing, so
add them to mainline in case we need to profile this stuff again. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
There are various bugs in block group trimming:
- It may trim from offset smaller than user-specified offset.
- It may trim beyond user-specified range.
- It may leak free space for extents smaller than specified minlen.
- It may truncate the last trimmed extent thus leak free space.
- With mixed extents+bitmaps, some extents may not be trimmed.
- With mixed extents+bitmaps, some bitmaps may not be trimmed (even
none will be trimmed). Even for those trimmed, not all the free space
in the bitmaps will be trimmed.
I rewrite btrfs_trim_block_group() and break it into two functions.
One is to trim extents only, and the other is to trim bitmaps only.
Before patching:
# fstrim -v /mnt/
/mnt/: 1496465408 bytes were trimmed
After patching:
# fstrim -v /mnt/
/mnt/: 2193768448 bytes were trimmed
And this matches the total free space:
# btrfs fi df /mnt
Data: total=3.58GB, used=1.79GB
System, DUP: total=8.00MB, used=4.00KB
System: total=4.00MB, used=0.00
Metadata, DUP: total=205.12MB, used=97.14MB
Metadata: total=8.00MB, used=0.00
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
If we run into some failure path in io_ctl_prepare_pages(),
io_ctl->pages[] array may have some NULL pointers.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
I got this while running xfstests:
[24256.836098] block group 317849600 has an wrong amount of free space
[24256.836100] btrfs: failed to load free space cache for block group 317849600
We should clamp the extent returned by find_first_extent_bit(),
so the start of the extent won't smaller than the start of the
block group.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (53 commits)
Kconfig: acpi: Fix typo in comment.
misc latin1 to utf8 conversions
devres: Fix a typo in devm_kfree comment
btrfs: free-space-cache.c: remove extra semicolon.
fat: Spelling s/obsolate/obsolete/g
SCSI, pmcraid: Fix spelling error in a pmcraid_err() call
tools/power turbostat: update fields in manpage
mac80211: drop spelling fix
types.h: fix comment spelling for 'architectures'
typo fixes: aera -> area, exntension -> extension
devices.txt: Fix typo of 'VMware'.
sis900: Fix enum typo 'sis900_rx_bufer_status'
decompress_bunzip2: remove invalid vi modeline
treewide: Fix comment and string typo 'bufer'
hyper-v: Update MAINTAINERS
treewide: Fix typos in various parts of the kernel, and fix some comments.
clockevents: drop unknown Kconfig symbol GENERIC_CLOCKEVENTS_MIGR
gpio: Kconfig: drop unknown symbol 'CS5535_GPIO'
leds: Kconfig: Fix typo 'D2NET_V2'
sound: Kconfig: drop unknown symbol ARCH_CLPS7500
...
Fix up trivial conflicts in arch/powerpc/platforms/40x/Kconfig (some new
kconfig additions, close to removed commented-out old ones)
Parameterize clusters on minimum total size, minimum chunk size and
minimum contiguous size for at least one chunk, without limits on
cluster, window or gap sizes. Don't tolerate any fragmentation for
SSD_SPREAD; accept it for metadata, but try to keep data dense.
Signed-off-by: Alexandre Oliva <oliva@lsd.ic.unicamp.br>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
The patch below removes an extra semicolon.
Signed-off-by: Justin P. Mattock <justinmattock@gmail.com>
CC: Chris Mason <chris.mason@oracle.com>
CC: linux-btrfs@vger.kernel.org
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
The field that indicates the size of the largest contiguous chunk of
free space in the cluster is not initialized when setting up bitmaps,
it's only increased when we find a larger contiguous chunk. We end up
retaining a larger value than appropriate for highly-fragmented
clusters, which may cause pointless searches for large contiguous
groups, and even cause clusters that do not meet the density
requirements to be set up.
Signed-off-by: Alexandre Oliva <oliva@lsd.ic.unicamp.br>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
We're failing to create clusters with bitmaps because
setup_cluster_no_bitmap checks that the list is empty before inserting
the bitmap entry in the list for setup_cluster_bitmap, but the list
field is only initialized when it is restored from the on-disk free
space cache, or when it is written out to disk.
Besides a potential race condition due to the multiple use of the list
field, filesystem performance severely degrades over time: as we use
up all non-bitmap free extents, the try-to-set-up-cluster dance is
done at every metadata block allocation. For every block group, we
fail to set up a cluster, and after failing on them all up to twice,
we fall back to the much slower unclustered allocation.
To make matters worse, before the unclustered allocation, we try to
create new block groups until we reach the 1% threshold, which
introduces additional bitmaps and thus block groups that we'll iterate
over at each metadata block request.
The log replay code only partially loads block groups, since
the block group caching code is able to detect and deal with
extents the logging code has pinned down.
While the logging code is pinning down block groups, there is
a bogus WARN_ON we're hitting if the code wasn't able to find
an extent in the cache. This commit removes the warning because
it can happen any time there isn't a valid free space cache
for that block group.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
When doing the io_ctl helpers to clean up the free space cache stuff I stopped
using our normal prepare_pages stuff, which means I of course forgot to do
things like set the pages extent mapped, which will cause us all sorts of
wonderful propblems. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
setup_cluster_no_bitmap() searches all the extents and bitmaps starting
from offset. Therefore if it returns -ENOSPC, all the bitmaps starting
from offset are in the bitmaps list, so it's sufficient to search from
this list in setup_cluser_bitmap().
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Suppose there are two bitmaps [0, 256], [256, 512] and one extent
[100, 120] in the free space cache, and we want to setup a cluster
with offset=100, bytes=50.
In this case, there will be only one bitmap [256, 512] in the temporary
bitmaps list, and then setup_cluster_bitmap() won't search bitmap [0, 256].
The cause is, the list is constructed in setup_cluster_no_bitmap(),
and only bitmaps with bitmap_entry->offset >= offset will be added
into the list, and the very bitmap that convers offset has
bitmap_entry->offset <= offset.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
People have been running into a warning when loading space cache because the
page is already mapped when trying to read in a bitmap. The way we read in
entries and pages is kind of convoluted, so fix it so that io_ctl_read_entry
maps the entries if it needs to, and if it hits the end of the page it simply
unmaps the page. That way we can unconditionally unmap the io_ctl before
reading in the bitmap and we should stop hitting these warnings. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
We no longer use the orphan block rsv for holding the reservation for truncating
the inode, so instead use the global block rsv and check to make sure it has
enough space for us to truncate the space. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
btrfs_remove_free_space needs to make sure to set ret back to a
valid return value after setting it to EAGAIN, otherwise we return
it to the callers.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
I noticed we had a little bit of latency when writing out the space cache
inodes. It's because we flush it before we write anything in case we have dirty
pages already there. This doesn't matter though since we're just going to
overwrite the space, and there really shouldn't be any dirty pages anyway. This
makes some of my tests run a little bit faster. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Currently btrfs_block_rsv_check does 2 things, it will either refill a block
reserve like in the truncate or refill case, or it will check to see if there is
enough space in the global reserve and possibly refill it. However because of
overcommit we could be well overcommitting ourselves just to try and refill the
global reserve, when really we should just be committing the transaction. So
breack this out into btrfs_block_rsv_refill and btrfs_block_rsv_check. Refill
will try to reserve more metadata if it can and btrfs_block_rsv_check will not,
it will only tell you if the factor of the total space is still reserved.
Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Yeah yeah I know this is how we used to do it and then I changed it, but damnit
I'm changing it back. The fact is that writing out checksums will modify
metadata, which could cause us to dirty a block group we've already written out,
so we have to truncate it and all of it's checksums and re-write it which will
write new checksums which could dirty a blockg roup that has already been
written and you see where I'm going with this? This can cause unmount or really
anything that depends on a transaction to commit to take it's sweet damned time
to happen. So go back to the way it was, only this time we're specifically
setting NODATACOW because we can't go through the COW pathway anyway and we're
doing our own built-in cow'ing by truncating the free space cache. The other
new thing is once we truncate the old cache and preallocate the new space, we
don't need to do that song and dance at all for the rest of the transaction, we
can just overwrite the existing space with the new cache if the block group
changes for whatever reason, and the NODATACOW will let us do this fine. So
keep track of which transaction we last cleared our cache in and if we cleared
it in this transaction just say we're all setup and carry on. This survives
xfstests and stress.sh.
The inode cache will continue to use the normal csum infrastructure since it
only gets written once and there will be no more modifications to the fs tree in
a transaction commit.
Signed-off-by: Josef Bacik <josef@redhat.com>
We need to check the return value of filemap_write_and_wait in the space cache
writeout code. Also don't set the inode's generation until we're sure nothing
else is going to fail. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
In writing and reading the space cache we have one big loop that keeps track of
which page we are on and then a bunch of sizeable loops underneath this big loop
to try and read/write out properly. Especially in the write case this makes
things hugely complicated and hard to follow, and makes our error checking and
recovery equally as complex. So add a io_ctl struct with a bunch of helpers to
keep track of the pages we have, where we are, if we have enough space etc.
This unifies how we deal with the pages we're writing and keeps all the messy
tracking internal. This allows us to kill the big loops in both the read and
write case and makes reviewing and chaning the write and read paths much
simpler. I've run xfstests and stress.sh on this code and it survives. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
I noticed a slight bug where we will not bother writing out the block group
cache's space cache if it's space tree is empty. Since it could have a cluster
or pinned extents that need to be written out this is just not a valid test.
Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Johannes pointed out we were allocating only kernel pages for doing writes,
which is kind of a big deal if you are on 32bit and have more than a gig of ram.
So fix our allocations to use the mapping's gfp but still clear __GFP_FS so we
don't re-enter. Thanks,
Reported-by: Johannes Weiner <jweiner@redhat.com>
Signed-off-by: Josef Bacik <josef@redhat.com>
The only thing that we need to have a trans handle for is in
reserve_metadata_bytes and thats to know how much flushing we can do. So
instead of passing it around, just check current->journal_info for a
trans_handle so we know if we can commit a transaction to try and free up space
or not. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Since free space inodes now use normal checksumming we need to make sure to
account for their metadata use. So reserve metadata space, and then if we fail
to write out the metadata we can just release it, otherwise it will be freed up
when the io completes. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
In moving some enospc stuff around I noticed that when we unmount we are often
evicting the free space cache inodes before we do our last commit. This isn't
bad, but it makes us constantly have to re-read the inodes back. So instead
don't evict the cache until after we do our last commit, this will make things a
little less crappy and makes a future enospc change work properly. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
We are setting ins_len to 1 even tho we are just modifying an item that should
be there already. This may cause the search stuff to split nodes on the way
down needelessly. Set this to 0 since we aren't inserting anything. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
If you run xfstest 224 it you will get lots of messages about not being able to
delete inodes and that they will be cleaned up next mount. This is because
btrfs_block_rsv_check was not calling reserve_metadata_bytes with the ability to
flush, so if there was not enough space, it simply failed. But in truncate and
evict case we could easily flush space to try and get enough space to do our
work, so make btrfs_block_rsv_check take a flush argument to pass down to
reserve_metadata_bytes. Now xfstests 224 runs fine without all those
complaints. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
A user reported getting spammed when moving to 3.0 by this message. Since we
switched to the normal checksumming infrastructure all old free space caches
will be wrong and need to be regenerated so people are likely to see this
message a lot, so ratelimit it so it doesn't fill up their logs and freak them
out. Thanks,
Reported-by: Andrew Lutomirski <luto@mit.edu>
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>
While truncating free space cache, we forget to change trans->block_rsv
back to the original one, but leave it with the orphan_block_rsv, and
then with option inode_cache enable, it leads to countless warnings of
btrfs_alloc_free_block and btrfs_orphan_commit_root:
WARNING: at fs/btrfs/extent-tree.c:5711 btrfs_alloc_free_block+0x180/0x350 [btrfs]()
...
WARNING: at fs/btrfs/inode.c:2193 btrfs_orphan_commit_root+0xb0/0xc0 [btrfs]()
Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Btrfs subtracted the size of the allocated space twice when it allocated
the space from the bitmap in the cluster, it broke the free space information
and led to oops finally.
And this patch also fixes the bug that ctl->free_space was subtracted
without lock.
Reported-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
grab_cache_page will use mapping_gfp_mask(), which for all inodes is set to
GFP_HIGHUSER_MOVABLE. So instead use find_or_create_page in all cases where we
need GFP_NOFS so we don't deadlock. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
We used to store the checksums of the space cache directly in the space cache,
however that doesn't work out too well if we have more space than we can fit the
checksums into the first page. So instead use the normal checksumming
infrastructure. There were problems with doing this originally but those
problems don't exist now so this works out fine. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
A user reported this bug again where we have more bitmaps than we are supposed
to. This is because we failed to load the free space cache, but don't update
the ctl->total_bitmaps counter when we remove entries from the tree. This patch
fixes this problem and we should be good to go again. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Josef recently changed the free extent cache to look in
the block group cluster for any bitmaps before trying to
add a new bitmap for the same offset. This avoids BUG_ON()s due
covering duplicate ranges.
But it didn't go quite far enough. A given free range might span
between one or more bitmaps or free space entries. The code has
looping to cover this, but it doesn't check for clustered bitmaps
every time.
This shuffles our gotos to check for a bitmap in the cluster
for every new bitmap entry we try to add.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
When merging my code into the integration test the second check for duplicate
entries got screwed up. This patch fixes it by dropping ret2 and just using ret
for the return value, and checking if we got an error before adding the bitmap
to the local list. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
In cleaning up the clustering code I accidently introduced a regression by
adding bitmap entries to the cluster rb tree. The problem is if we've maxed out
the number of bitmaps we can have for the block group we can only add free space
to the bitmaps, but since the bitmap is on the cluster we can't find it and we
try to create another one. This would result in a panic because the total
bitmaps was bigger than the max bitmaps that were allowed. This patch fixes
this by checking to see if we have a cluster, and then looking at the cluster rb
tree to see if it has a bitmap entry and if it does and that space belongs to
that bitmap, go ahead and add it to that bitmap.
I could hit this panic every time with an fs_mark test within a couple of
minutes. With this patch I no longer hit the panic and fs_mark goes to
completion. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
When profiling the find cluster code it's hard to tell where we are spending our
time because the bitmap and non-bitmap functions get inlined by the compiler, so
make that not happen. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
If we are looking for a cluster in a particularly sparse or fragmented block
group, we will do a lot of looping through the free space tree looking for
various things, and if we need to look at bitmaps we will endup doing the whole
dance twice. So instead add the bitmap entries to a temporary list so if we
have to do the bitmap search we can just look through the list of entries we've
found quickly instead of having to loop through the entire tree again. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
This makes the inode map cache default to off until we
fix the overflow problem when the free space crcs don't fit
inside a single page.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
The free space cache uses only one page for crcs right now,
which means we can't have a cache file bigger than the
crcs we can fit in the first page. This adds a check to
enforce that restriction.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
If there are duplicate entries in the free space cache, discard the entire cache
and load it the old fashioned way. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Remove static and global declarations and/or definitions. Reduces size
of btrfs.ko by ~3.4kB.
text data bss dec hex filename
402081 7464 200 409745 64091 btrfs.ko.base
398620 7144 200 405964 631cc btrfs.ko.remove-all
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>
If our space cache is wrong, we do the right thing and free up everything that
we loaded, however we don't reset the total_bitmaps counter or the thresholds or
anything. So in btrfs_remove_free_space_cache make sure to call free_bitmap()
if it's a bitmap, this will keep us from panicing when we check to make sure we
don't have too many bitmaps. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Since commit dc89e98244, we've changed
to use a specific slab for alocation of free_space items.
Signed-off-by: Li Zefan <lizf@cn.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>
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>
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>
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>
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>
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>
This patch makes the free space cluster refilling code a little easier to
understand, and fixes some things with the bitmap part of it. Currently we
either want to refill a cluster with
1) All normal extent entries (those without bitmaps)
2) A bitmap entry with enough space
The current code has this ugly jump around logic that will first try and fill up
the cluster with extent entries and then if it can't do that it will try and
find a bitmap to use. So instead split this out into two functions, one that
tries to find only normal entries, and one that tries to find bitmaps.
This also fixes a suboptimal thing we would do with bitmaps. If we used a
bitmap we would just tell the cluster that we were pointing at a bitmap and it
would do the tree search in the block group for that entry every time we tried
to make an allocation. Instead of doing that now we just add it to the clusters
group.
I tested this with my ENOSPC tests and xfstests and it survived.
Signed-off-by: Josef Bacik <josef@redhat.com>
We have been creating bitmaps for small extents unconditionally forever. This
was great when testing to make sure the bitmap stuff was working, but is
overkill normally. So instead of always adding small chunks of free space to
bitmaps, only start doing it if we go past half of our extent threshold. This
will keeps us from creating a bitmap for just one small free extent at the front
of the block group, and will make the allocator a little faster as a result.
Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
We do all this fun stuff with min_bytes, but either don't use it in the case of
just normal extents, or use it completely wrong in the case of bitmaps. So fix
this for both cases
1) In the extent case, stop looking for space with window_free >= min_bytes
instead of bytes + empty_size.
2) In the bitmap case, we were looking for streches of free space that was at
least min_bytes in size, which was not right at all. So instead search for
stretches of free space that are at least bytes in size (this will make a
difference when we have > page size blocks) and then only search for min_bytes
amount of free space.
Thanks,
Reviewed-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Josef Bacik <josef@redhat.com>
The free space cluster stuff is heavy duty, so there is no sense in going
through the entire song and dance if there isn't enough space in the block group
to begin with. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Since we alloc/free free space entries a whole lot, lets use a slab to keep
track of them. This makes some of my tests slightly faster. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
When we're cleaning up the tree log we need to be able to remove free space from
the block group. The problem is if that free space spans bitmaps we would not
find the space since we're looking for too many bytes. So make sure the amount
of bytes we search for is limited to either the number of bytes we want, or the
number of bytes left in the bitmap. This was tested by a user who was hitting
the BUG() after search_bitmap. With this patch he can now mount his fs.
Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
After returing extents from a cluster to the block group, some
extents in the block group may be mergeable.
Reviewed-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
When adding a new extent, we'll firstly see if we can merge
this extent to the left or/and right extent. Extract this as
a helper try_merge_free_space().
As a side effect, we fix a small bug that if the new extent
has non-bitmap left entry but is unmergeble, we'll directly
link the extent without trying to drop it into bitmap.
This also prepares for the next patch.
Reviewed-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
When allocating extent entry from a cluster, we should update
the free_space and free_extents fields of the block group.
Reviewed-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
If there's no more free space in a bitmap, we should free it.
Reviewed-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Remove some duplicated code.
This prepares for the next patch.
Reviewed-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
If a block group is smaller than 1GB, the extent entry threadhold
calculation will always set the threshold to 0.
So as free space gets fragmented, btrfs will switch to use bitmap
to manage free space, but then will never switch back to extents
due to this bug.
Reviewed-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.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>
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>
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>
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>
btrfs inialize rb trees in quite a number of places by settin rb_node =
NULL; The problem with this is that 17d9ddc72f in the
linux-next tree adds a new field to that struct which needs to be NULL for
the new rbtree library code to work properly. This patch uses RB_ROOT as
the intializer so all of the relevant fields will be NULL'd. Without the
patch I get a panic.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
This patch fixes a problem where max_size can be set to 0 even though we
filled the cluster properly. We set max_size to 0 if we restart the cluster
window, but if the new start entry is big enough to be our new cluster then we
could return with a max_size set to 0, which will mean the next time we try to
allocate from this cluster it will fail. So set max_extent to the entry's
size. Tested this on my box and now we actually allocate from the cluster
after we fill it. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
There is a slight problem with the extent entry threshold calculation for the
free space cache. We only adjust the threshold down as we add bitmaps, but
never actually adjust the threshold up as we add bitmaps. This means we could
fragment the free space so badly that we end up using all bitmaps to describe
the free space, use all the free space which would result in the bitmaps being
freed, but then go to add free space again as we delete things and immediately
add bitmaps since the extent threshold would still be 0. Now as we free
bitmaps the extent threshold will be ratcheted up to allow more extent entries
to be added.
Signed-off-by: Josef Bacik <jbacik@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
When we first go to add free space, we allocate a new info and set the offset
and bytes to the space we are adding. This is fine, except we actually set the
size of a bitmap as we set the bits in it, so if we add space to a bitmap, we'd
end up counting the same space twice. This isn't a huge deal, it just makes
the allocator behave weirdly since it will think that a bitmap entry has more
space than it ends up actually having. I used a BUG_ON() to catch when this
problem happened, and with this patch I no longer get the BUG_ON().
Signed-off-by: Josef Bacik <jbacik@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Yan Zheng hit a problem where we tried to remove some free space but failed
because we couldn't find the free space entry. This is because the free space
was held within a bitmap that had a starting offset well before the actual
offset of the free space, and there were free space extents that were in the
same range as that offset, so tree_search_offset returned with NULL because we
couldn't find a free space extent that had that offset. This is fixed by
making sure that if we fail to find the entry, we re-search again with
bitmap_only set to 1 and do an offset_to_bitmap so we can get the appropriate
bitmap. A similar problem happens in btrfs_alloc_from_bitmap for the
clustering code, but that is not as bad since we will just go and redo our
cluster allocation.
Also this adds some debugging checks to make sure that the free space we are
trying to remove from the bitmap is in fact there. This can probably go away
after a while, but since this code is only used by the tree-logging stuff it
would be nice to run with it for a while to make sure there are no problems.
Signed-off-by: Josef Bacik <jbacik@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Jeff Mahoney
Linus Torvalds
Tsutomu Itoh
Masanari Iida
Josef Bacik
Chris Mason
Li Zefan
Alexandre Oliva
Justin P. Mattock
Alexandre Oliva
Liu Bo
Miao Xie
David Sterba
Li Dongyang
Tejun Heo
Eric Paris