Naohiro Aota [Fri, 25 Aug 2017 05:15:14 +0000 (14:15 +0900)]
btrfs: fix NULL pointer dereference from free_reloc_roots()
__del_reloc_root should be called before freeing up reloc_root->node.
If not, calling __del_reloc_root() dereference reloc_root->node, causing
the system BUG.
Fixes: 6bdf131fac23 ("Btrfs: don't leak reloc root nodes on error") Cc: <stable@vger.kernel.org> # 4.9 Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
btrfs: finish ordered extent cleaning if no progress is found
__endio_write_update_ordered() repeats the search until it reaches the end
of the specified range. This works well with direct IO path, because before
the function is called, it's ensured that there are ordered extents filling
whole the range. It's not the case, however, when it's called from
run_delalloc_range(): it is possible to have error in the midle of the loop
in e.g. run_delalloc_nocow(), so that there exisits the range not covered
by any ordered extents. By cleaning such "uncomplete" range,
__endio_write_update_ordered() stucks at offset where there're no ordered
extents.
Since the ordered extents are created from head to tail, we can stop the
search if there are no offset progress.
btrfs: clear ordered flag on cleaning up ordered extents
Commit 524272607e88 ("btrfs: Handle delalloc error correctly to avoid
ordered extent hang") introduced btrfs_cleanup_ordered_extents() to cleanup
submitted ordered extents. However, it does not clear the ordered bit
(Private2) of corresponding pages. Thus, the following BUG occurs from
free_pages_check_bad() (on btrfs/125 with nospace_cache).
Omar Sandoval [Wed, 23 Aug 2017 06:46:00 +0000 (23:46 -0700)]
Btrfs: fix incorrect {node,sector}size endianness from BTRFS_IOC_FS_INFO
fs_info->super_copy->{node,sector}size are little-endian, but the ioctl
should return the values in native endianness. Use the cached values in
btrfs_fs_info instead. Found with sparse.
Fixes: 80a773fbfc2d ("btrfs: retrieve more info from FS_INFO ioctl") Signed-off-by: Omar Sandoval <osandov@fb.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Liu Bo [Wed, 23 Aug 2017 18:15:09 +0000 (12:15 -0600)]
Btrfs: do not reset bio->bi_ops while writing bio
flush_epd_write_bio() sets bio->bi_opf by itself to honor REQ_SYNC,
but it's not needed at all since bio->bi_opf has set up properly in
both __extent_writepage() and write_one_eb(), and in the case of
write_one_eb(), it also sets REQ_META, which we will lose in
flush_epd_write_bio().
This remove this unnecessary bio->bi_opf setting.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Liu Bo [Fri, 25 Aug 2017 00:19:48 +0000 (18:19 -0600)]
Btrfs: use the new helper wbc_to_write_flags
This updates btrfs to use the helper wbc_to_write_flags which has been
applied in ext4/xfs/f2fs/block.
Please note that, with this, btrfs's dirty pages written by a
writeback job will carry the flag REQ_BACKGROUND, which is currently
used by writeback-throttle to determine whether it should go to get a
request or wait.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba [Fri, 18 Aug 2017 16:16:25 +0000 (18:16 +0200)]
btrfs: submit superblock io with REQ_META and REQ_PRIO
The superblock is also metadata of the filesystem so the relevant IO
should be tagged as such. We also tag it as high priority, as it's the
last block committed for metadata from a given transaction. Any delays
would effectively block the whole transaction, also blocking any other
operation holding the device_list_mutex.
Reviewed-by: Josef Bacik <jbacik@fb.com> Reviewed-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
Nikolay Borisov [Tue, 1 Aug 2017 15:25:56 +0000 (18:25 +0300)]
btrfs: remove unnecessary memory barrier in btrfs_direct_IO
Commit 38851cc19adb ("Btrfs: implement unlocked dio write") implemented
unlocked dio write, allowing multiple dio writers to write to
non-overlapping, and non-eof-extending regions. In doing so it also
introduced a broken memory barrier. It is broken due to 2 things:
1. Memory barriers _MUST_ always be paired, this is clearly not the case
here
2. Checkpatch actually produces a warning if a memory barrier is
introduced that doesn't have a comment explaining how it's being
paired.
Specifically for inode::i_dio_count that's wrapped inside
inode_dio_begin, there is no explicit barrier semantics attached, so
removing is fine as the atomic is used in common the waiter/wakeup
pattern.
Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com>
[ enhance changelog ] Signed-off-by: David Sterba <dsterba@suse.com>
Nikolay Borisov [Fri, 18 Aug 2017 14:58:23 +0000 (17:58 +0300)]
btrfs: remove superfluous chunk_tree argument from btrfs_alloc_dev_extent
Currently this function is always called with the object id of the root
key of the chunk_tree, which is always BTRFS_CHUNK_TREE_OBJECTID. So
let's subsume it straight into the function itself. No functional
change.
Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Nikolay Borisov [Fri, 18 Aug 2017 14:58:22 +0000 (17:58 +0300)]
btrfs: Remove chunk_objectid parameter of btrfs_alloc_dev_extent
THe function is always called with chunk_objectid set to
BTRFS_FIRST_CHUNK_TREE_OBJECTID. Let's collapse the parameter in the
function itself. No functional changes.
Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Liu Bo [Fri, 18 Aug 2017 21:15:24 +0000 (15:15 -0600)]
Btrfs: add one more sanity check for shared ref type
Every shared ref has a parent tree block, which can be get from
btrfs_extent_inline_ref_offset(). And the tree block must be aligned
to the nodesize, so we'd know this inline ref is not valid if this
block's bytenr is not aligned to the nodesize, in which case, most
likely the ref type has been misused.
This adds the above mentioned check and also updates
print_extent_item() called by btrfs_print_leaf() to point out the
invalid ref while printing the tree structure.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
Liu Bo [Fri, 18 Aug 2017 21:15:23 +0000 (15:15 -0600)]
Btrfs: remove BUG_ON in __add_tree_block
The BUG_ON() can be triggered when the caller is processing an invalid
extent inline ref, e.g.
a shared data ref is offered instead of an extent data ref, such that
it tries to find a non-existent tree block and then btrfs_search_slot
returns 1 for no such item.
This replaces the BUG_ON() with a WARN() followed by calling
btrfs_print_leaf() to show more details about what's going on and
returning -EINVAL to upper callers.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Liu Bo [Fri, 18 Aug 2017 21:15:21 +0000 (15:15 -0600)]
Btrfs: remove BUG() in print_extent_item
btrfs_print_leaf() is used in btrfs_get_extent_inline_ref_type, so
here we really want to print the invalid value of ref type instead of
causing a kernel panic.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Liu Bo [Fri, 18 Aug 2017 21:15:20 +0000 (15:15 -0600)]
Btrfs: remove BUG() in btrfs_extent_inline_ref_size
Now that btrfs_get_extent_inline_ref_type() can report if type is a
valid one and all callers can gracefully deal with that, we don't need
to crash here.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Liu Bo [Fri, 18 Aug 2017 21:15:18 +0000 (15:15 -0600)]
Btrfs: add a helper to retrive extent inline ref type
An invalid value of extent inline ref type may be read from a
malicious image which may force btrfs to crash.
This adds a helper which does sanity check for the ref type, so we can
know if it's sane, return he type, otherwise return an error.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com>
[ minimal tweak const types, causing warnings due to other cleanup patches ] Signed-off-by: David Sterba <dsterba@suse.com>
When changing a file's acl mask, btrfs_set_acl() will first set the
group bits of i_mode to the value of the mask, and only then set the
actual extended attribute representing the new acl.
If the second part fails (due to lack of space, for example) and the
file had no acl attribute to begin with, the system will from now on
assume that the mask permission bits are actual group permission bits,
potentially granting access to the wrong users.
Prevent this by restoring the original mode bits if __btrfs_set_acl
fails.
Signed-off-by: Ernesto A. Fernández <ernesto.mnd.fernandez@gmail.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Nikolay Borisov [Thu, 27 Jul 2017 11:37:29 +0000 (14:37 +0300)]
btrfs: Remove extraneous chunk_objectid variable
BTRFS_FIRST_CHUNK_TREE_OBJECTIS id the only objectid being used in the
chunk_tree. So remove a variable which is always set to that value and collapse
its usage in callees which are passed this variable. No functional changes
Signed-off-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Nikolay Borisov [Thu, 27 Jul 2017 11:22:11 +0000 (14:22 +0300)]
btrfs: Remove chunk_objectid argument from btrfs_make_block_group
btrfs_make_block_group is always called with chunk_objectid set to
BTRFS_FIRST_CHUNK_TREE_OBJECTID. There's no reason why this behavior will
change anytime soon, so let's remove the argument and decrease the cognitive
load when reading the code path. No functional change
Signed-off-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Nikolay Borisov [Fri, 28 Jul 2017 07:50:14 +0000 (10:50 +0300)]
btrfs: Remove redundant setting of uuid in btrfs_block_header
btrfs_alloc_dev_extent currently unconditionally sets the uuid in the
leaf block header the function is working with. This is unnecessary
since this operation is peformed by the core btree handling code
(splitting a node, allocating a new btree block etc). So let's remove
it.
Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
This patch provides a band aid to improve the 'out of the box'
behaviour of btrfs for disks that are detected as being an ssd. In a
general purpose mixed workload scenario, the current ssd mode causes
overallocation of available raw disk space for data, while leaving
behind increasing amounts of unused fragmented free space. This
situation leads to early ENOSPC problems which are harming user
experience and adoption of btrfs as a general purpose filesystem.
This patch modifies the data extent allocation behaviour of the ssd mode
to make it behave identical to nossd mode. The metadata behaviour and
additional ssd_spread option stay untouched so far.
Recommendations for future development are to reconsider the current
oversimplified nossd / ssd distinction and the broken detection
mechanism based on the rotational attribute in sysfs and provide
experienced users with a more flexible way to choose allocator behaviour
for data and metadata, optimized for certain use cases, while keeping
sane 'out of the box' default settings. The internals of the current
btrfs code have more potential than what currently gets exposed to the
user to choose from.
The SSD story...
In the first year of btrfs development, around early 2008, btrfs
gained a mount option which enables specific functionality for
filesystems on solid state devices. The first occurance of this
functionality is in commit e18e4809, labeled "Add mount -o ssd, which
includes optimizations for seek free storage".
The effect on allocating free space for doing (data) writes is to
'cluster' writes together, writing them out in contiguous space, as
opposed to a 'tetris' way of putting all separate writes into any free
space fragment that fits (which is what the -o nossd behaviour does).
A somewhat simplified explanation of what happens is that, when for
example, the 'cluster' size is set to 2MiB, when we do some writes, the
data allocator will search for a free space block that is 2MiB big, and
put the writes in there. The ssd mode itself might allow a 2MiB cluster
to be composed of multiple free space extents with some existing data in
between, while the additional ssd_spread mount option kills off this
option and requires fully free space.
The idea behind this is (commit 536ac8ae): "The [...] clusters make it
more likely a given IO will completely overwrite the ssd block, so it
doesn't have to do an internal rwm cycle."; ssd block meaning nand erase
block. So, effectively this means applying a "locality based algorithm"
and trying to outsmart the actual ssd.
Since then, various changes have been made to the involved code, but the
basic idea is still present, and gets activated whenever the ssd mount
option is active. This also happens by default, when the rotational flag
as seen at /sys/block/<device>/queue/rotational is set to 0.
However, there's a number of problems with this approach.
First, what the optimization is trying to do is outsmart the ssd by
assuming there is a relation between the physical address space of the
block device as seen by btrfs and the actual physical storage of the
ssd, and then adjusting data placement. However, since the introduction
of the Flash Translation Layer (FTL) which is a part of the internal
controller of an ssd, these attempts are futile. The use of good quality
FTL in consumer ssd products might have been limited in 2008, but this
situation has changed drastically soon after that time. Today, even the
flash memory in your automatic cat feeding machine or your grandma's
wheelchair has a full featured one.
Second, the behaviour as described above results in the filesystem being
filled up with badly fragmented free space extents because of relatively
small pieces of space that are freed up by deletes, but not selected
again as part of a 'cluster'. Since the algorithm prefers allocating a
new chunk over going back to tetris mode, the end result is a filesystem
in which all raw space is allocated, but which is composed of
underutilized chunks with a 'shotgun blast' pattern of fragmented free
space. Usually, the next problematic thing that happens is the
filesystem wanting to allocate new space for metadata, which causes the
filesystem to fail in spectacular ways.
Third, the default mount options you get for an ssd ('ssd' mode enabled,
'discard' not enabled), in combination with spreading out writes over
the full address space and ignoring freed up space leads to worst case
behaviour in providing information to the ssd itself, since it will
never learn that all the free space left behind is actually free. There
are two ways to let an ssd know previously written data does not have to
be preserved, which are sending explicit signals using discard or
fstrim, or by simply overwriting the space with new data. The worst
case behaviour is the btrfs ssd_spread mount option in combination with
not having discard enabled. It has a side effect of minimizing the reuse
of free space previously written in.
Fourth, the rotational flag in /sys/ does not reliably indicate if the
device is a locally attached ssd. For example, iSCSI or NBD displays as
non-rotational, while a loop device on an ssd shows up as rotational.
The combination of the second and third problem effectively means that
despite all the good intentions, the btrfs ssd mode reliably causes the
ssd hardware and the filesystem structures and performance to be choked
to death. The clickbait version of the title of this story would have
been "Btrfs ssd optimizations considered harmful for ssds".
The current nossd 'tetris' mode (even still without discard) allows a
pattern of overwriting much more previously used space, causing many
more implicit discards to happen because of the overwrite information
the ssd gets. The actual location in the physical address space, as seen
from the point of view of btrfs is irrelevant, because the actual writes
to the low level flash are reordered anyway thanks to the FTL.
Changes made in the code
1. Make ssd mode data allocation identical to tetris mode, like nossd.
2. Adjust and clean up filesystem mount messages so that we can easily
identify if a kernel has this patch applied or not, when providing
support to end users. Also, make better use of the *_and_info helpers to
only trigger messages on actual state changes.
Backporting notes
Notes for whoever wants to backport this patch to their 4.9 LTS kernel:
* First apply commit 951e7966 "btrfs: drop the nossd flag when
remounting with -o ssd", or fixup the differences manually.
* The rest of the conflicts are because of the fs_info refactoring. So,
for example, instead of using fs_info, it's root->fs_info in
extent-tree.c
Signed-off-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com> Signed-off-by: David Sterba <dsterba@suse.com>
Lu Fengqi [Fri, 18 Aug 2017 08:38:07 +0000 (16:38 +0800)]
btrfs: use btrfsic_submit_bio instead of submit_bio in write_dev_flush
Although this bio has no data attached, it will reach this condition
(bio->bi_opf & REQ_PREFLUSH) and then update the flush_gen of dev_state
in __btrfsic_submit_bio. So we should still submit it through integrity
checker. Otherwise, the integrity checker will throw the following warning
when I mount a newly created btrfs filesystem.
[10264.755497] btrfs: attempt to write superblock which references block M @29523968 (sdb1/1111654400/0) which is not flushed out of disk's write cache (block flush_gen=1, dev->flush_gen=0)!
[10264.755498] btrfs: attempt to write superblock which references block M @29523968 (sdb1/37912576/0) which is not flushed out of disk's write cache (block flush_gen=1, dev->flush_gen=0)!
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Filipe Manana [Thu, 10 Aug 2017 21:54:51 +0000 (22:54 +0100)]
Btrfs: incremental send, fix emission of invalid clone operations
When doing an incremental send it's possible that the computed send stream
contains clone operations that will fail on the receiver if the receiver
has compression enabled and the clone operations target a sector sized
extent that starts at a zero file offset, is not compressed on the source
filesystem but ends up being compressed and inlined at the destination
filesystem.
Example scenario:
$ mkfs.btrfs -f /dev/sdb
$ mount -o compress /dev/sdb /mnt
# By doing a direct IO write, the data is not compressed.
$ xfs_io -f -d -c "pwrite -S 0xab 0 4K" /mnt/foobar
$ btrfs subvolume snapshot -r /mnt /mnt/mysnap1
$ mkfs.btrfs -f /dev/sdc
$ mount -o compress /dev/sdc /mnt
$ btrfs receive -f /tmp/1.snap /mnt
$ btrfs receive -f /tmp/2.snap /mnt
ERROR: failed to clone extents to foobar
Operation not supported
The same could be achieved by mounting the source filesystem without
compression and doing a buffered IO write instead of a direct IO one,
and mounting the destination filesystem with compression enabled.
So fix this by issuing regular write operations in the send stream
instead of clone operations when the source offset is zero and the
range has a length matching the sector size.
Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
Liu Bo [Wed, 9 Aug 2017 17:10:16 +0000 (11:10 -0600)]
Btrfs: fix out of bounds array access while reading extent buffer
There is a corner case that slips through the checkers in functions
reading extent buffer, ie.
if (start < eb->len) and (start + len > eb->len),
then
a) map_private_extent_buffer() returns immediately because
it's thinking the range spans across two pages,
b) and the checkers in read_extent_buffer(), WARN_ON(start > eb->len)
and WARN_ON(start + len > eb->start + eb->len), both are OK in this
corner case, but it'd actually try to access the eb->pages out of
bounds because of (start + len > eb->len).
The case is found by switching extent inline ref type from shared data
ref to non-shared data ref, which is a kind of metadata corruption.
It'd use the wrong helper to access the eb,
eg. btrfs_extent_data_ref_root(eb, ref) is used but the %ref passing
here is "struct btrfs_shared_data_ref". And if the extent item
happens to be the first item in the eb, then offset/length will get
over eb->len which ends up an invalid memory access.
This is adding proper checks in order to avoid invalid memory access,
ie. 'general protection fault', before it's too late.
Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
Nikolay Borisov [Fri, 4 Aug 2017 11:41:18 +0000 (14:41 +0300)]
btrfs: Fix -EOVERFLOW handling in btrfs_ioctl_tree_search_v2
The buffer passed to btrfs_ioctl_tree_search* functions have to be at least
sizeof(struct btrfs_ioctl_search_header). If this is not the case then the
ioctl should return -EOVERFLOW and set the uarg->buf_size to the minimum
required size. Currently btrfs_ioctl_tree_search_v2 would return an -EOVERFLOW
error with ->buf_size being set to the value passed by user space. Fix this by
removing the size check and relying on search_ioctl, which already includes it
and correctly sets buf_size.
Signed-off-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Chris Mason <clm@fb.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Nikolay Borisov [Thu, 3 Aug 2017 12:44:58 +0000 (15:44 +0300)]
btrfs: Move skip checksum check from btrfs_submit_direct to __btrfs_submit_dio_bio
Currently the code checks whether we should do data checksumming in
btrfs_submit_direct and the boolean result of this check is passed to
btrfs_submit_direct_hook, in turn passing it to __btrfs_submit_dio_bio which
actually consumes it. The last function actually has all the necessary context
to figure out whether to skip the check or not, so let's move the check closer
to where it's being consumed. No functional changes.
Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Chris Mason <clm@fb.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
Filipe Manana [Fri, 28 Jul 2017 14:22:36 +0000 (15:22 +0100)]
Btrfs: fix assertion failure during fsync in no-holes mode
When logging an inode in full mode that has an inline compressed extent
that represents a range with a size matching the sector size (currently
the same as the page size), has a trailing hole and the no-holes feature
is enabled, we end up failing an assertion leading to a trace like the
following:
Which happens because the code that logs a trailing hole when the no-holes
feature is enabled, did not consider that a compressed inline extent can
represent a range with a size matching the sector size, in which case
expanding the inode's i_size, through a truncate operation, won't lead
to padding with zeroes the page that represents the inline extent, and
therefore the inline extent remains after the truncation.
Fix this by adapting the assertion to accept inline extents representing
data with a sector size length if, and only if, the inline extents are
compressed.
A sample and trivial reproducer (for systems with a 4K page size) for this
issue:
Filipe Manana [Thu, 27 Jul 2017 18:52:55 +0000 (19:52 +0100)]
Btrfs: avoid unnecessarily locking inode when clearing a range
If the range being cleared was not marked for defrag and we are not
about to clear the range from the defrag status, we don't need to
lock and unlock the inode.
Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Chris Mason <clm@fb.com> Reviewed-by: Wang Shilong <wangshilong1991@gmail.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
Colin Ian King [Tue, 15 Aug 2017 07:51:02 +0000 (08:51 +0100)]
btrfs: remove redundant check on ret being non-zero
The error return variable ret is initialized to zero and then is
checked to see if it is non-zero in the if-block that follows it.
It is therefore impossible for ret to be non-zero after the if-block
hence the check is redundant and can be removed.
Detected by CoverityScan, CID#1021040 ("Logically dead code")
Signed-off-by: Colin Ian King <colin.king@canonical.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Nikolay Borisov [Wed, 16 Aug 2017 15:15:23 +0000 (18:15 +0300)]
btrfs: expose internal free space tree routine only if sanity tests are enabled
The internal free space tree management routines are always exposed for
testing purposes. Make them dependent on SANITY_TESTS being on so that
they are exposed only when they really have to.
Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Nikolay Borisov [Wed, 16 Aug 2017 15:41:44 +0000 (18:41 +0300)]
btrfs: Remove unused sectorsize variable from struct map_lookup
This variable was added in 1abe9b8a138c ("Btrfs: add initial tracepointi
support for btrfs"), yet it never really got used, only assigned to. So
let's remove it.
Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Josef Bacik [Mon, 24 Jul 2017 19:14:26 +0000 (15:14 -0400)]
btrfs: increase ctx->pos for delayed dir index
Our dir_context->pos is supposed to hold the next position we're
supposed to look. If we successfully insert a delayed dir index we
could end up with a duplicate entry because we don't increase ctx->pos
after doing the dir_emit.
Signed-off-by: Josef Bacik <jbacik@fb.com> Reviewed-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
Josef Bacik [Mon, 24 Jul 2017 19:14:25 +0000 (15:14 -0400)]
btrfs: fix readdir deadlock with pagefault
Readdir does dir_emit while under the btree lock. dir_emit can trigger
the page fault which means we can deadlock. Fix this by allocating a
buffer on opening a directory and copying the readdir into this buffer
and doing dir_emit from outside of the tree lock.
Thread A
readdir <holding tree lock>
dir_emit
<page fault>
down_read(mmap_sem)
Thread B
mmap write
down_write(mmap_sem)
page_mkwrite
wait_ordered_extents
Process C
finish_ordered_extent
insert_reserved_file_extent
try to lock leaf <hang>
Signed-off-by: Josef Bacik <jbacik@fb.com> Reviewed-by: David Sterba <dsterba@suse.com>
[ copy the deadlock scenario to changelog ] Signed-off-by: David Sterba <dsterba@suse.com>
Nikolay Borisov [Thu, 22 Jun 2017 13:51:48 +0000 (09:51 -0400)]
btrfs: Simplify math in should_alloc chunk
Currently should_alloc_chunk uses ->total_bytes - ->bytes_readonly to
signify the total amount of bytes in this space info. However, given
Jeff's patch which adds bytes_pinned and bytes_may_use to the calculation
of num_allocated it becomes a lot more clear to just eliminate num_bytes
altogether and add the bytes_readonly to the amount of used space. That
way we don't change the results of the following statements. In the
process also start using btrfs_space_info_used.
Signed-off-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Jeff Mahoney [Thu, 22 Jun 2017 13:51:47 +0000 (09:51 -0400)]
btrfs: account for pinned bytes in should_alloc_chunk
In a heavy write scenario, we can end up with a large number of pinned bytes.
This can translate into (very) premature ENOSPC because pinned bytes
must be accounted for when allowing a reservation but aren't accounted for
when deciding whether to create a new chunk.
This patch adds the accounting to should_alloc_chunk so that we can
create the chunk.
Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba [Mon, 17 Jul 2017 16:11:10 +0000 (18:11 +0200)]
btrfs: prepare for extensions in compression options
This is a minimal patch intended to be backported to older kernels.
We're going to extend the string specifying the compression method and
this would fail on kernels before that change (the string is compared
exactly).
Relax the string matching only to the prefix, ie. ignoring anything that
goes after "zlib" or "lzo", regardless of th format extension we decide
to use. This applies to the mount options and properties.
That way, patched old kernels could be booted on systems already
utilizing the new compression spec.
David Sterba [Mon, 17 Jul 2017 18:42:03 +0000 (20:42 +0200)]
btrfs: allow defrag compress to override NOCOMPRESS attribute
Currently, the BTRFS_INODE_NOCOMPRESS will prevent any compression on a
given file, except when the mount is force-compress. As users have
reported on IRC, this will also prevent compression when requested by
defrag (btrfs fi defrag -c file).
The nocompress flag is set automatically by filesystem when the ratios
are bad and the user would have to manually drop the bit in order to
make defrag -c work. This is not good from the usability perspective.
This patch will raise priority for the defrag -c over nocompress, ie.
any file with NOCOMPRESS bit set will get defragmented. The bit will
remain untouched.
Alternate option was to also drop the nocompress bit and keep the
decision logic as is, but I think this is not the right solution.
David Sterba [Mon, 17 Jul 2017 17:41:31 +0000 (19:41 +0200)]
btrfs: separate defrag and property compression
Add new value for compression to distinguish between defrag and
property. Previously, a single variable was used and this caused clashes
when the per-file 'compression' was set and a defrag -c was called.
The property-compression is loaded when the file is open, defrag will
overwrite the same variable and reset to 0 (ie. NONE) at when the file
defragmentaion is finished. That's considered a usability bug.
Now we won't touch the property value, use the defrag-compression. The
precedence of defrag is higher than for property (and whole-filesystem).
David Sterba [Mon, 17 Jul 2017 17:17:20 +0000 (19:17 +0200)]
btrfs: rename variable holding per-inode compression type
This is preparatory for separating inode compression requested by defrag
and set via properties. This will fix a usability bug when defrag will
reset compression type to NONE. If the file has compression set via
property, it will not apply anymore (until next mount or reset through
command line).
We're going to fix that by adding another variable just for the defrag
call and won't touch the property. The defrag will have higher priority
when deciding whether to compress the data.
Btrfs: add skeleton code for compression heuristic
Add skeleton code for compresison heuristics. Now it iterates over all
the pages, but in the end always says "yes, compress please", ie it does
not change the current behaviour.
In the future we're going to add various heuristics to analyze the data.
This patch can be used as a baseline for measuring if the effectivness
and performance.
Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com> Reviewed-by: David Sterba <dsterba@suse.com>
[ enhanced changelog, modified comments ] Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba [Wed, 19 Jul 2017 17:26:45 +0000 (19:26 +0200)]
btrfs: account that we're waiting for DIO read
Correctly account for IO when waiting for a submitted DIO read, the case
when we're retrying. This only for the accounting purposes and should
not change other behaviour.
Nikolay Borisov [Tue, 25 Jul 2017 14:48:28 +0000 (17:48 +0300)]
btrfs: Make flush_space return void
The return value of flush_space was used to have significance in the
early days when the code was first introduced and before the ticketed
enospc rework. Since the latter got introduced the return value lost any
significance whatsoever to its callers. So let's remove it. While at it
also remove the unused ticket variable in
btrfs_async_reclaim_metadata_space. It was used in the initial version
of the ticketed ENOSPC work, however Wang Xiaoguang detected a problem
with this and fixed it in ce129655c9d9 ("btrfs: introduce tickets_id to
determine whether asynchronous metadata reclaim work makes progress").
Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com>
[ add comment ] Signed-off-by: David Sterba <dsterba@suse.com>
Nikolay Borisov [Wed, 26 Jul 2017 08:26:28 +0000 (11:26 +0300)]
btrfs: Deprecate userspace transaction ioctls
Userspace transactions were introduced in commit 6bf13c0cc833 ("Btrfs:
transaction ioctls") to provide semantics that Ceph's object store
required. However, things have changed significantly since then, to the
point where btrfs is no longer suitable as a backend for ceph and in
fact it's actively advised against such usages. Considering this, there
doesn't seem to be a widespread, legit use case of userspace
transaction. They also clutter the file->private pointer.
So to end the agony let's nuke the userspace transaction ioctls. As a
first step let's give time for people to voice their objection by just
WARN()ining when the userspace transaction is used.
Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com>
[ move the warning past perm checks, keep the has-been-printed state;
we're ok with just one warning over all filesystems ] Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba [Thu, 15 Jun 2017 23:48:05 +0000 (01:48 +0200)]
btrfs: use named constant for bdev blocksize
Superblock is read and written using buffer heads, we need to set the
bdev blocksize. The magic constant has been hardcoded in several places,
so replace it with a named constant.
David Sterba [Thu, 15 Jun 2017 22:50:33 +0000 (00:50 +0200)]
btrfs: split write_dev_supers to two functions
There are two independent parts, one that writes the superblocks and
another that waits for completion. No functional changes, but cleanups,
reformatting and comment updates.
David Sterba [Thu, 15 Jun 2017 17:51:51 +0000 (19:51 +0200)]
btrfs: refactor find_device helper
Polish the helper:
* drop underscores, no special meaning here
* pass fs_devices, as this is what the API implements
* drop noinline, no apparent reason for such simple helper
* constify uuid
* add comment
David Sterba [Wed, 14 Jun 2017 00:48:07 +0000 (02:48 +0200)]
btrfs: merge alloc_device helpers
There are two helpers called in chain from one location, we can merge the
functionaliy.
Originally, alloc_fs_devices could fill the device uuid randomly if we
we didn't give the uuid buffer. This happens for seed devices but the
fsid is generated in btrfs_prepare_sprout, so we can remove it.
David Sterba [Tue, 6 Jun 2017 17:14:26 +0000 (19:14 +0200)]
btrfs: merge REQ_OP and REQ_ flags to one parameter in submit_extent_page
The function submit_extent_page has 15(!) parameters right now, op and
op_flags are effectively one value stored to bio::bi_opf, no need to
pass them separately. So it's 14 parameters now.
David Sterba [Wed, 14 Jun 2017 14:28:42 +0000 (16:28 +0200)]
btrfs: simplify btrfs_dev_replace_kthread
This function prints an informative message and then continues
dev-replace. The message contains a progress percentage which is read
from the status. The status is allocated dynamically, about 2600 bytes,
just to read the single value. That's an overkill. We'll use the new
helper and drop the allocation.
David Sterba [Thu, 22 Jun 2017 01:22:58 +0000 (03:22 +0200)]
btrfs: defrag: make readahead state allocation failure non-fatal
All sorts of readahead errors are not considered fatal. We can continue
defragmentation without it, with some potential slow down, which will
last only for the current inode.
David Sterba [Thu, 22 Jun 2017 00:26:54 +0000 (02:26 +0200)]
btrfs: use GFP_KERNEL in mount and remount
We don't need to restrict the allocation flags in btrfs_mount or
_remount. No big filesystem locks are held (possibly s_umount but that
does no count here).
Nikolay Borisov [Thu, 13 Jul 2017 11:11:07 +0000 (14:11 +0300)]
btrfs: Remove never reached error handling code in __add_reloc_root
One of the error handling paths in __add_reloc_root contains btrfs_panic()
followed by some other code. As the name implies what it does is print
some error message and call BUG, naturally what follow afterwards is not
invoked. So remove this extra code.
Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Nikolay Borisov [Wed, 19 Jul 2017 07:47:57 +0000 (10:47 +0300)]
btrfs: Remove unused variables
clear_super - usage was removed in commit cea67ab92d3d ("btrfs: clean
the old superblocks before freeing the device") but that change forgot
to remove the actual variable.
max_key - commit 6174d3cb43aa ("Btrfs: remove unused max_key arg from
btrfs_search_forward") removed the max_key parameter but it forgot to
remove references from callers.
stripe_len - this one was added by e06cd3dd7cea ("Btrfs: add validadtion
checks for chunk loading") but even then it wasn't used.
Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Nikolay Borisov [Fri, 14 Jul 2017 06:55:41 +0000 (09:55 +0300)]
btrfs: Remove find_raid56_stripe_len
find_raid56_stripe_len statically returns SZ_64K which equals BTRFS_STRIPE_LEN.
It's sole caller is __btrfs_alloc_chunk and it assigns the return value to ai
variable which is already set to BTRFS_STRIPE_LEN. So remove the function
invocation altogether and remove the function itself. Also remove the variable
since it's only aliasing BTRFS_STRIPE_LEN and use the define directly. Use
the occassion to simplify the rounding down of stripe_size now that the value
we want it to align is a power of 2.
Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Qu Wenruo <quwenruo.btrfs@gmx.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Nick Terrell [Thu, 29 Jun 2017 17:57:26 +0000 (10:57 -0700)]
btrfs: Keep one more workspace around
find_workspace() allocates up to num_online_cpus() + 1 workspaces.
free_workspace() will only keep num_online_cpus() workspaces. When
(de)compressing we will allocate num_online_cpus() + 1 workspaces, then
free one, and repeat. Instead, we can just keep num_online_cpus() + 1
workspaces around, and never have to allocate/free another workspace in the
common case.
I tested on a Ubuntu 14.04 VM with 2 cores and 4 GiB of RAM. I mounted a
BtrFS partition with -o compress-force={lzo,zlib,zstd} and logged whenever
a workspace was allocated of freed. Then I copied vmlinux (527 MB) to the
partition. Before the patch, during the copy it would allocate and free 5-6
workspaces. After, it only allocated the initial 3. This held true for lzo,
zlib, and zstd. The time it took to execute cp vmlinux /mnt/btrfs && sync
dropped from 1.70s to 1.44s with lzo compression, and from 2.04s to 1.80s
for zstd compression.
Signed-off-by: Nick Terrell <terrelln@fb.com> Reviewed-by: Omar Sandoval <osandov@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba [Thu, 13 Jul 2017 13:32:18 +0000 (15:32 +0200)]
btrfs: drop newlines from strings when using btrfs_* helpers
The helpers append "\n" so we can keep the actual strings shorter. The
extra newline will print an empty line. Some messages have been
slightly modified to be more consistent with the rest (lowercase first
letter).
Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Nikolay Borisov [Wed, 12 Jul 2017 06:42:19 +0000 (09:42 +0300)]
btrfs: qgroups: Fix BUG_ON condition in tree level check
The current code was erroneously checking for
root_level > BTRFS_MAX_LEVEL. If we had a root_level of 8 then the check
won't trigger and we could potentially hit a buffer overflow. The
correct check should be root_level >= BTRFS_MAX_LEVEL .
Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Qu Wenruo <quwenruo.btrfs@gmx.com> Signed-off-by: David Sterba <dsterba@suse.com>
Qu Wenruo [Thu, 9 Mar 2017 01:34:42 +0000 (09:34 +0800)]
btrfs: Enhance message when a device is missing during mount
For a missing device, btrfs will just refuse to mount with almost
meaningless kernel message like:
BTRFS info (device vdb6): disk space caching is enabled
BTRFS info (device vdb6): has skinny extents
BTRFS error (device vdb6): failed to read the system array: -5
BTRFS error (device vdb6): open_ctree failed
This patch will print a new message about the missing device:
BTRFS info (device vdb6): disk space caching is enabled
BTRFS info (device vdb6): has skinny extents
BTRFS warning (device vdb6): devid 2 uuid 80470722-cad2-4b90-b7c3-fee294552f1b is missing
BTRFS error (device vdb6): failed to read the system array: -5
BTRFS error (device vdb6): open_ctree failed
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Qu Wenruo [Tue, 27 Jun 2017 09:28:40 +0000 (17:28 +0800)]
btrfs: Allow barrier_all_devices to do chunk level device check
The last user of num_tolerated_disk_barrier_failures is
barrier_all_devices().
But it can be easily changed to the new per-chunk degradable check
framework.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Qu Wenruo [Thu, 9 Mar 2017 01:34:37 +0000 (09:34 +0800)]
btrfs: Do chunk level check for degraded rw mount
Now use the btrfs_check_rw_degradable() to check if we can mount in the
degraded mode.
With this patch, we can mount in the following case:
# mkfs.btrfs -f -m raid1 -d single /dev/sdb /dev/sdc
# wipefs -a /dev/sdc
# mount /dev/sdb /mnt/btrfs -o degraded
As the single data chunk is only on sdb, so it's OK to mount as
degraded, as missing one device is OK for RAID1.
But still fail in the following case as expected:
# mkfs.btrfs -f -m raid1 -d single /dev/sdb /dev/sdc
# wipefs -a /dev/sdb
# mount /dev/sdc /mnt/btrfs -o degraded
As the data chunk is only in sdb, so it's not OK to mount it as
degraded.
Reported-by: Zhao Lei <zhaolei@cn.fujitsu.com> Reported-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Qu Wenruo [Thu, 9 Mar 2017 01:34:36 +0000 (09:34 +0800)]
btrfs: Introduce a function to check if all chunks a OK for degraded rw mount
Introduce a new function, btrfs_check_rw_degradable(), to check if all
chunks in btrfs is OK for degraded rw mount.
It provides the new basis for accurate btrfs mount/remount and even
runtime degraded mount check other than old one-size-fit-all method.
Btrfs currently uses num_tolerated_disk_barrier_failures to do global
check for tolerated missing device.
Although the one-size-fit-all solution is quite safe, it's too strict
if data and metadata has different duplication level.
For example, if one use Single data and RAID1 metadata for 2 disks, it
means any missing device will make the fs unable to be degraded
mounted.
But in fact, some times all single chunks may be in the existing
device and in that case, we should allow it to be rw degraded mounted.
Such case can be easily reproduced using the following script:
# mkfs.btrfs -f -m raid1 -d sing /dev/sdb /dev/sdc
# wipefs -f /dev/sdc
# mount /dev/sdb -o degraded,rw
If using btrfs-debug-tree to check /dev/sdb, one should find that the
data chunk is only in sdb, so in fact it should allow degraded mount.
This patchset will introduce a new per-chunk degradable check for
btrfs, allow above case to succeed, and it's quite small anyway.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com>
[ copied text from cover letter with more details about the problem being
solved ] Signed-off-by: David Sterba <dsterba@suse.com>
Liu Bo [Tue, 11 Jul 2017 20:43:16 +0000 (14:43 -0600)]
Btrfs: report errors when checksum is not found
When btrfs fails the checksum check, it'll fill the whole page with
"1".
However, if %csum_expected is 0 (which means there is no checksum), then
for some unknown reason, we just pretend that the read is correct, so
userspace would be confused about the dilemma that read is successful but
getting a page with all content being "1".
This can happen due to a bug in btrfs-convert.
This fixes it by always returning errors if checksum doesn't match.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Nikolay Borisov [Tue, 11 Jul 2017 13:55:51 +0000 (16:55 +0300)]
btrfs: Prevent possible ERR_PTR() dereference
In btrfs_full_stripe_len/btrfs_is_parity_mirror we have similar code which
gets the chunk map for a particular range via get_chunk_map. However,
get_chunk_map can return an ERR_PTR value and while the 2 callers do catch
this with a WARN_ON they then proceed to indiscriminately dereference the
extent map. This of course leads to a crash. Fix the offenders by making the
dereference conditional on IS_ERR.
Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Nikolay Borisov [Tue, 11 Jul 2017 10:47:50 +0000 (13:47 +0300)]
btrfs: Remove redundant checks from btrfs_alloc_data_chunk_ondemand
Many commits ago the data space_info in alloc_data_chunk_ondemand used to be
acquired from the inode. At that point commit 33b4d47f5e24 ("Btrfs: deal with NULL space info") got introduced to deal with
spurios cases where the space info could be null, following a rebalance.
Nowadays, however, the space info is referenced directly from the btrfs_fs_info
struct which is initialised at filesystem mount time. This makes the null
checks redundant, so remove them.
Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Nikolay Borisov [Tue, 11 Jul 2017 10:25:13 +0000 (13:25 +0300)]
btrfs: Remove redundant argument of flush_space
All callers of flush_space pass the same number for orig/num_bytes
arguments. Let's remove one of the numbers and also modify the trace
point to show only a single number - bytes requested.
Seems that last point where the two parameters were treated differently
is before the ticketed enospc rework.
Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Several distributions mount the "proper root" as ro during initrd and
then remount it as rw before pivot_root(2). Thus, if a rescan had been
aborted by a previous shutdown, the rescan would never be resumed.
This issue would manifest itself as several btrfs ioctl(2)s causing the
entire machine to hang when btrfs_qgroup_wait_for_completion was hit
(due to the fs_info->qgroup_rescan_running flag being set but the rescan
itself not being resumed). Notably, Docker's btrfs storage driver makes
regular use of BTRFS_QUOTA_CTL_DISABLE and BTRFS_IOC_QUOTA_RESCAN_WAIT
(causing this problem to be manifested on boot for some machines).
Cc: <stable@vger.kernel.org> # v3.11+ Cc: Jeff Mahoney <jeffm@suse.com> Fixes: b382a324b60f ("Btrfs: fix qgroup rescan resume on mount") Signed-off-by: Aleksa Sarai <asarai@suse.de> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Tested-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Edmund Nadolski [Wed, 12 Jul 2017 22:20:11 +0000 (16:20 -0600)]
btrfs: clean up extraneous computations in add_delayed_refs
Repeating the same computation in multiple places is not
necessary.
Signed-off-by: Edmund Nadolski <enadolski@suse.com> Signed-off-by: Jeff Mahoney <jeffm@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Edmund Nadolski [Wed, 12 Jul 2017 22:20:10 +0000 (16:20 -0600)]
btrfs: allow backref search checks for shared extents
When called with a struct share_check, find_parent_nodes()
will detect a shared extent and immediately return with
BACKREF_SHARED_FOUND.
Signed-off-by: Edmund Nadolski <enadolski@suse.com> Signed-off-by: Jeff Mahoney <jeffm@suse.com> Reviewed-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
Edmund Nadolski [Wed, 12 Jul 2017 22:20:09 +0000 (16:20 -0600)]
btrfs: add cond_resched() calls when resolving backrefs
Since backref resolution is CPU-intensive, the cond_resched calls
should help alleviate soft lockup occurences.
Signed-off-by: Edmund Nadolski <enadolski@suse.com> Signed-off-by: Jeff Mahoney <jeffm@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Jeff Mahoney [Wed, 12 Jul 2017 22:20:08 +0000 (16:20 -0600)]
btrfs: backref, add tracepoints for prelim_ref insertion and merging
This patch adds a tracepoint event for prelim_ref insertion and
merging. For each, the ref being inserted or merged and the count
of tree nodes is issued.
Signed-off-by: Jeff Mahoney <jeffm@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Jeff Mahoney [Wed, 12 Jul 2017 22:20:07 +0000 (16:20 -0600)]
btrfs: add a node counter to each of the rbtrees
This patch adds counters to each of the rbtrees so that we can tell
how large they are growing for a given workload. These counters
will be exported by tracepoints in the next patch.
Signed-off-by: Jeff Mahoney <jeffm@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Edmund Nadolski [Wed, 12 Jul 2017 22:20:06 +0000 (16:20 -0600)]
btrfs: convert prelimary reference tracking to use rbtrees
It's been known for a while that the use of multiple lists
that are periodically merged was an algorithmic problem within
btrfs. There are several workloads that don't complete in any
reasonable amount of time (e.g. btrfs/130) and others that cause
soft lockups.
The solution is to use a set of rbtrees that do insertion merging
for both indirect and direct refs, with the former converting
refs into the latter. The result is a btrfs/130 workload that
used to take several hours now takes about half of that. This
runtime still isn't acceptable and a future patch will address that
by moving the rbtrees higher in the stack so the lookups can be
shared across multiple calls to find_parent_nodes.
Signed-off-by: Edmund Nadolski <enadolski@suse.com> Signed-off-by: Jeff Mahoney <jeffm@suse.com> Reviewed-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
projects / mirror_ubuntu-jammy-kernel.git / log