Add a documentation blob that explains what the i_version field is, how
it is expected to work, and how it is currently implemented by various
filesystems.
We already have inode_inc_iversion. Add several other functions for
manipulating and accessing the i_version counter. For now, the
implementation is trivial and basically works the way that all of the
open-coded i_version accesses work today.
Future patches will convert existing users of i_version to use the new
API, and then convert the backend implementation to do things more
efficiently.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
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Merge tag 'for-4.15-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fix from David Sterba:
"It's been reported recently that readdir can list stale entries under
some conditions. Fix it."
* tag 'for-4.15-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
Btrfs: fix stale entries in readdir
In fixing the readdir+pagefault deadlock I accidentally introduced a
stale entry regression in readdir. If we get close to full for the
temporary buffer, and then skip a few delayed deletions, and then try to
add another entry that won't fit, we will emit the entries we found and
retry. Unfortunately we delete entries from our del_list as we find
them, assuming we won't need them. However our pos will be with
whatever our last entry was, which could be before the delayed deletions
we skipped, so the next search will add the deleted entries back into
our readdir buffer. So instead don't delete entries we find in our
del_list so we can make sure we always find our delayed deletions. This
is a slight perf hit for readdir with lots of pending deletions, but
hopefully this isn't a common occurrence. If it is we can revist this
and optimize it.
cc: stable@vger.kernel.org
Fixes: 23b5ec7494 ("btrfs: fix readdir deadlock with pagefault")
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There is no other parent for device_list_add() except for
btrfs_scan_one_device(), which would set btrfs_fs_devices::total_devices
if device_list_add is successful and this can be done with in
device_list_add() itself.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Commit 60999ca4b4 ("btrfs: make device scan less noisy")
adds return value 1 to device_list_add(), so that parent function can
call pr_info only when new device is added. Move the pr_info() part
into device_list_add() so that this function can be kept simple.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The btrfs_free_stale_devices() is updated to match for the given device
path and delete it. (It searches for only unmounted list of devices.)
Also drop the comment about different path being used for the same
device, since now we will have cli to clean any device that's not a
concern any more.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
No functional changes.
Rename btrfs_free_stale_devices() arg to skip_dev, so that it
reflects what that arg for.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This updates btrfs_free_stale_devices() helper function to delete all
unmouted devices, when arg is NULL.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Let the list iterator iterate further and find other stale
devices and delete it. This is in preparation to add support
for user land request-able stale devices cleanup. Also rename
btrfs_free_stale_device() to btrfs_free_stale_devices().
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There is no need to check for btrfs_fs_devices::seeding when we
have checked for btrfs_fs_devices::opened, because we can't sprout
without its seed FS being opened.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
No functional changes, just makes the code more readable
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In order to debug subtle bugs around merge_extent_mapping(), perf probe
can be used to check the arguments, but sometimes merge_extent_mapping()
got inlined by compiler and couldn't be probed.
This is adding noinline attribute to merge_extent_mapping().
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is a subtle case, so in order to understand the problem, it'd be good
to know the content of existing and em when any error occurs.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This test case simulates the racy situation of dio write vs dio read,
and see if btrfs_get_extent() would return -EEXIST.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This test case simulates the racy situation of buffered write vs dio
read, and see if btrfs_get_extent() would return -EEXIST.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We've observed that btrfs_get_extent() and merge_extent_mapping() could
return -EEXIST in several cases, and they are caused by some racy
condition, e.g dio read vs dio write, which makes the problem very tricky
to reproduce.
This adds extent map selftests in order to simulate those racy situations.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
[ minor string adjustments ]
Signed-off-by: David Sterba <dsterba@suse.com>
These helpers are extent map specific, move them to extent_map.c.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is a prepare work for the following extent map selftest, which
runs tests against em merge logic.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This fixes a corner case that is caused by a race of dio write vs dio
read/write.
Here is how the race could happen.
Suppose that no extent map has been loaded into memory yet.
There is a file extent [0, 32K), two jobs are running concurrently
against it, t1 is doing dio write to [8K, 32K) and t2 is doing dio
read from [0, 4K) or [4K, 8K).
t1 goes ahead of t2 and splits em [0, 32K) to em [0K, 8K) and [8K 32K).
------------------------------------------------------
t1 t2
btrfs_get_blocks_direct() btrfs_get_blocks_direct()
-> btrfs_get_extent() -> btrfs_get_extent()
-> lookup_extent_mapping()
-> add_extent_mapping() -> lookup_extent_mapping()
# load [0, 32K)
-> btrfs_new_extent_direct()
-> btrfs_drop_extent_cache()
# split [0, 32K) and
# drop [8K, 32K)
-> add_extent_mapping()
# add [8K, 32K)
-> add_extent_mapping()
# handle -EEXIST when adding
# [0, 32K)
------------------------------------------------------
About how t2(dio read/write) runs into -EEXIST:
a) add_extent_mapping() gets -EEXIST for adding em [0, 32k),
b) search_extent_mapping() then returns [0, 8k) as the existing em,
even though start == existing->start, em is [0, 32k) so that
extent_map_end(em) > extent_map_end(existing), i.e. 32k > 8k,
c) then it goes thru merge_extent_mapping() which tries to add a [8k, 8k)
(with a length 0) and returns -EEXIST as [8k, 32k) is already in tree,
d) so btrfs_get_extent() ends up returning -EEXIST to dio read/write,
which is confusing applications.
Here I conclude all the possible situations,
1) start < existing->start
+-----------+em+-----------+
+--prev---+ | +-------------+ |
| | | | | |
+---------+ + +---+existing++ ++
+
|
+
start
2) start == existing->start
+------------em------------+
| +-------------+ |
| | | |
+ +----existing-+ +
|
|
+
start
3) start > existing->start && start < (existing->start + existing->len)
+------------em------------+
| +-------------+ |
| | | |
+ +----existing-+ +
|
|
+
start
4) start >= (existing->start + existing->len)
+-----------+em+-----------+
| +-------------+ | +--next---+
| | | | | |
+ +---+existing++ + +---------+
+
|
+
start
As we can see, it turns out that if start is within existing em (front
inclusive), then the existing em should be returned as is, otherwise,
we try our best to merge candidate em with sibling ems to form a
larger em (in order to reduce the total number of em).
Reported-by: David Vallender <david.vallender@landmark.co.uk>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
%block_len could be checked on deciding if two em are mergeable.
merge_extent_mapping() has only added the front pad if the front part
of em gets truncated, but it's possible that the end part gets
truncated.
For both compressed extent and inline extent, em->block_len is not
adjusted accordingly, and for regular extent, em->block_len always
equals to em->len, hence this sets em->block_len with em->len.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The reada_lock in struct btrfs_device was only initialised, and not
actually used. That's good because there's another lock also called
reada_lock in the btrfs_fs_info that was quite heavily used. Remove
this one.
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Before rbio_orig_end_io() goes to free rbio, rbio may get merged with
more bios from other rbios and rbio->bio_list becomes non-empty,
in that case, these newly merged bios don't end properly.
Once unlock_stripe() is done, rbio->bio_list will not be updated any
more and we can call bio_endio() on all queued bios.
It should only happen in error-out cases, the normal path of recover
and full stripe write have already set RBIO_RMW_LOCKED_BIT to disable
merge before doing IO, so rbio_orig_end_io() called by them doesn't
have the above issue.
Reported-by: Jérôme Carretero <cJ-ko@zougloub.eu>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Since raid6 recover tries all possible combinations of failed stripes,
- when raid6 rebuild algorithm is used, i.e. raid6_datap_recov() and
raid6_2data_recov(), it may change the in-memory content of failed
stripes, if such a raid bio is cached, a later raid write rmw or recover
can steal @stripe_pages from it instead of reading from disks, such that
it carries the wrong content to do write rmw or recovery and ends up
with corruption or recovery failures.
- when raid5 rebuild algorithm is used, i.e. xor, raid bio can be cached
because the only failed stripe which contains @rbio->bio_pages gets
modified, others remain the same so that their in-memory content is
consistent with their on-disk content.
This adds a check to skip caching rbio if using raid6 recover.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Bio iterated by set_bio_pages_uptodate() is raid56 internal one, so it
will never be a BIO_CLONED bio, and since this is called by end_io
functions, bio->bi_iter.bi_size is zero, we mustn't use
bio_for_each_segment() as that is a no-op if bi_size is zero.
Fixes: 6592e58c6b ("Btrfs: fix write corruption due to bio cloning on raid5/6")
Cc: <stable@vger.kernel.org> # v4.12-rc6+
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There is no function named btrfs_get_inode_index_count.
Explanation for magic number index_cnt=2 in btrfs_new_inode() is
actually located in btrfs_set_inode_index_count().
So replace 'btrfs_get_inode_index_count' in the comment by
'btrfs_set_inode_index_count'.
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
It's not used outside of extent-tree so there is no reason to not be
static.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We call btrfs_free_stale_device() only when we alloc a new struct
btrfs_device (ret=1), so move it closer to where we alloc the new
device. Also drop the comments.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
I've noticed that the updated item checker stack consumption increased
dramatically in 542f5385e20cf97447 ("btrfs: tree-checker: Add checker
for dir item")
tree-checker.c:check_leaf +552 (176 -> 728)
The array is 255 bytes long, dynamic allocation would slow down the
sanity checks so it's more reasonable to keep it on-stack. Moving the
variable to the scope of use reduces the stack usage again
tree-checker.c:check_leaf -264 (728 -> 464)
Reviewed-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
gcc-8 reports:
fs/btrfs/ioctl.c: In function 'btrfs_ioctl':
./include/linux/string.h:245:9: warning: '__builtin_strncpy' specified
bound 1024 equals destination size [-Wstringop-truncation]
We need one less byte or call strlcpy() to make it a nul-terminated
string. This is done on the next line anyway, but we want to avoid the
warning.
Signed-off-by: Xiongfeng Wang <xiongfeng.wang@linaro.org>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
It appears from the original commit [1] that there isn't any design
specific reason not to fail the mount instead of just warning. This
patch will change it to fail.
[1]
commit 319e4d0661
btrfs: Enhance super validation check
Fixes: 319e4d0661 ("btrfs: Enhance super validation check")
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs-progs uses super flag bit BTRFS_SUPER_FLAG_METADUMP_V2 (1ULL << 34).
So just define that in kernel so that we know its been used.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We've avoided data losing raid profile when doing balance, but it
turns out that deleting a device could also result in the same
problem.
Say we have 3 disks, and they're created with '-d raid1' profile.
- We have chunk P (the only data chunk on the empty btrfs).
- Suppose that chunk P's two raid1 copies reside in disk A and disk B.
- Now, 'btrfs device remove disk B'
btrfs_rm_device()
-> btrfs_shrink_device()
-> btrfs_relocate_chunk() #relocate any chunk on disk B
to other places.
- Chunk P will be removed and a new chunk will be created to hold
those data, but as chunk P is the only one holding raid1 profile,
after it goes away, the new chunk will be created as single profile
which is our default profile.
This fixes the problem by creating an empty data chunk before
relocating the data chunk.
Metadata/System chunk are supposed to have non-zero bytes all the time
so their raid profile is preserved.
Reported-by: James Alandt <James.Alandt@wdc.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
For a fallocate's zero range operation that targets a range with an end
that is not aligned to the sector size, we can end up not updating the
inode's i_size. This happens when the last page of the range maps to an
unwritten (prealloc) extent and before that last page we have either a
hole or a written extent. This is because in this scenario we relied
on a call to btrfs_prealloc_file_range() to update the inode's i_size,
however it can only update the i_size to the "down aligned" end of the
range.
Example:
$ mkfs.btrfs -f /dev/sdc
$ mount /dev/sdc /mnt
$ xfs_io -f -c "pwrite -S 0xff 0 428K" /mnt/foobar
$ xfs_io -c "falloc -k 428K 4K" /mnt/foobar
$ xfs_io -c "fzero 0 430K" /mnt/foobar
$ du --bytes /mnt/foobar
438272 /mnt/foobar
The inode's i_size was left as 428Kb (438272 bytes) when it should have
been updated to 430Kb (440320 bytes).
Fix this by always updating the inode's i_size explicitly after zeroing
the range.
Fixes: ba6d5887946ff86d93dc ("Btrfs: add support for fallocate's zero range operation")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
During a buffered IO write, we can have an extent state that we got when
we locked the range (if the range starts at an offset lower than eof), so
always pass it to btrfs_dirty_pages() so that setting the delalloc bit
in the range does not need to do a full search in the inode's io tree,
saving time and reducing the amount of time we hold the io tree's lock.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This implements support the zero range operation of fallocate. For now
at least it's as simple as possible while reusing most of the existing
fallocate and hole punching infrastructure.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Since fail stripe index in rbio would be used to decide which
algorithm reconstruction would be run, we cannot merge rbios if
their's fail striped indexes are different, otherwise, one of the two
reconstructions would fail.
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>
Given the above
'
if (last->operation != cur->operation)
return 0;
',
it's guaranteed that two operations are same.
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>
Assign ret = -EINVAL where it is actually required.
Remove { } around single line if else code.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_device::scrub_device is not a device which is being scrubbed,
but it holds the scrub context, so rename to reflect the same. No
functional changes here.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There is no other consumer for btrfs_handle_error() other than
__btrfs_handle_fs_error(), further this function quite small.
Merge it into its parent.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
[ reformat comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
__btrfs_handle_fs_error() sets BTRFS_FS_STATE_ERROR, and calls
btrfs_handle_error() so no need to check if the BTRFS_FS_STATE_ERROR
is set in btrfs_handle_error(). And there is no other user of
btrfs_handle_error() as well.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There is a scenario that can end up with rebuild process failing to
return good content, i.e.
suppose that all disks can be read without problems and if the content
that was read out doesn't match its checksum, currently for raid6
btrfs at most retries twice,
- the 1st retry is to rebuild with all other stripes, it'll eventually
be a raid5 xor rebuild,
- if the 1st fails, the 2nd retry will deliberately fail parity p so
that it will do raid6 style rebuild,
however, the chances are that another non-parity stripe content also
has something corrupted, so that the above retries are not able to
return correct content, and users will think of this as data loss.
More seriouly, if the loss happens on some important internal btree
roots, it could refuse to mount.
This extends btrfs to do more retries and each retry fails only one
stripe. Since raid6 can tolerate 2 disk failures, if there is one
more failure besides the failure on which we're recovering, this can
always work.
The worst case is to retry as many times as the number of raid6 disks,
but given the fact that such a scenario is really rare in practice,
it's still acceptable.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The raid6 corruption is that,
suppose that all disks can be read without problems and if the content
that was read out doesn't match its checksum, currently for raid6
btrfs at most retries twice,
- the 1st retry is to rebuild with all other stripes, it'll eventually
be a raid5 xor rebuild,
- if the 1st fails, the 2nd retry will deliberately fail parity p so
that it will do raid6 style rebuild,
however, the chances are that another non-parity stripe content also
has something corrupted, so that the above retries are not able to
return correct content.
We've fixed normal reads to rebuild raid6 correctly with more retries
in Patch "Btrfs: make raid6 rebuild retry more"[1], this is to fix
scrub to do the exactly same rebuild process.
[1]: https://patchwork.kernel.org/patch/10091755/
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Update btrfs_check_rw_degradable() to check against the given device if
its lost.
We can use this function to know if the volume is going to be in
degraded mode OR failed state, when the given device fails. Which is
needed when we are handling the device failed state.
A preparatory patch does not affect the flow as such.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
[ enhance comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
All callers pass either GFP_NOFS or GFP_KERNEL now, so we can sink the
parameter to the function, though we lose some of the slightly better
semantics of GFP_KERNEL in some places, it's worth cleaning up the
callchains.
Signed-off-by: David Sterba <dsterba@suse.com>
There's only one instance where we pass different gfp mask to
unlock_extent_cached. Add a separate helper for that and then we can
drop the gfp parameter from unlock_extent_cached.
Signed-off-by: David Sterba <dsterba@suse.com>
Recent patches reworking the mount path left some unused parameters. We
pass a vfsmount to mount_subvol, the flags and data (ie. mount options)
have been already applied and we will not need them.
Signed-off-by: David Sterba <dsterba@suse.com>
Long ago, commit edf24abe51 ("btrfs: sanity mount option parsing and
early mount code") split the btrfs_parse_options() into two parts
(btrfs_parse_early_options() and btrfs_parse_options()). As a result,
btrfs_parse_optins no longer gets called twice and is the last one to
parse mount option string. Therefore there is no need to dup it.
Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In fact nobody is waiting on @wait's waitqueue, it can be safely
removed.
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>
The bio is not referenced after it has been submitted and the endio is
going to consume the sole reference on successful submission. On error,
the callers of __btrfs_submit_dio_bio do invoke bio_put so we don't
leak it either.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The bio is never referenced after it has been submitted so there is no
point in getting an extra reference.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The bio that is passsed is the newly created repair bio which already
has a reference count of 1, which is going to be consumed by the
endio routine on successful submission. On error the handler also
calls bio_put.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
bio_get/set is necessary only if the bio is going to be referenced
following submissions. In the code paths where such calls are made
we don't really need them since the bio is referenced only if
btrfs_map_bio returns an error. And this function can return an error
prior to submission only. So referencing the bio is safe. Furthermore
we do call bio_endio which will consume the last reference. So let's
remove the redundant calls.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
As it's a single instance and local to the file, we don't need to pass
it as an argument.
Reviewed-by: Timofey Titovets <nefelim4ag@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The callback is trivial and we don't need the abstraction for our
purposes. Let's open code it.
Reviewed-by: Timofey Titovets <nefelim4ag@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The callback is trivial and we don't need the abstraction for our
purposes. Let's open code it and also make the array types explicit.
Reviewed-by: Timofey Titovets <nefelim4ag@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Remove unused arg 'holder' from parse_subvol_options(), which has been
forgotten to be cleaned in the commit b99beb110e2d ("btrfs: split
parse_early_options() in two").
Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Since setup_root_args() is not used anymore, just remove it.
Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now parse_early_options() is used by both btrfs_mount() and
btrfs_mount_root(). However, the former only needs subvol related part
and the latter needs the others.
Therefore extract the subvol related parts from parse_early_options() and
move it to new parse function (parse_subvol_options()).
Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Cleanup btrfs_mount() by using btrfs_mount_root(). This avoids getting
btrfs_mount() called twice in mount path.
Old btrfs_mount() will do:
0. VFS layer calls vfs_kern_mount() with registered file_system_type
(for btrfs, btrfs_fs_type). btrfs_mount() is called on the way.
1. btrfs_parse_early_options() parses "subvolid=" mount option and set the
value to subvol_objectid. Otherwise, subvol_objectid has the initial
value of 0
2. check subvol_objectid is 5 or not. Assume this time id is not 5, then
btrfs_mount() returns by calling mount_subvol()
3. In mount_subvol(), original mount options are modified to contain
"subvolid=0" in setup_root_args(). Then, vfs_kern_mount() is called with
btrfs_fs_type and new options
4. btrfs_mount() is called again
5. btrfs_parse_early_options() parses "subvolid=0" and set 5 (instead of 0)
to subvol_objectid
6. check subvol_objectid is 5 or not. This time id is 5 and mount_subvol()
is not called. btrfs_mount() finishes mounting a root
7. (in mount_subvol()) with using a return vale of vfs_kern_mount(), it
calls mount_subtree()
8. return subvolume's dentry
Reusing the same file_system_type (and btrfs_mount()) for vfs_kern_mount()
is the cause of complication.
Instead, new btrfs_mount() will do:
1. parse subvol id related options for later use in mount_subvol()
2. mount device's root by calling vfs_kern_mount() with
btrfs_root_fs_type, which is not registered to VFS by
register_filesystem(). As a result, btrfs_mount_root() is called
3. return by calling mount_subvol()
The code of 2. is moved from the first part of mount_subvol().
The semantics of device holder changes from btrfs_fs_type to
btrfs_root_fs_type and has to be used in all contexts. Otherwise we'd
get wrong results when mount and dev scan would not check the same
thing. (this has been found indendently and the fix is folded into this
patch)
Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ fold the btrfs_control_ioctl fixup, extend the comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
Add btrfs_mount_root() and new file_system_type for preparation of cleanup
of btrfs_mount(). Code path is not changed yet.
btrfs_mount_root() is almost the same as current btrfs_mount(), but doesn't
have subvolume related part.
Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Functions called from extent_write_cache_pages used void* as generic
callback data, but all of them convert it to extent_page_data, or use it
directly.
Signed-off-by: David Sterba <dsterba@suse.com>
The function extent_write_cache_pages is modelled after
write_cache_pages which is a generic interface and the writepage
parameter makes sense there. In btrfs we know exactly which callback
we're going to use, so we can pass it directly.
Signed-off-by: David Sterba <dsterba@suse.com>
flush_epd_write_bio is same as flush_write_bio, no point having two such
functions. Merge them to flush_write_bio. The 'noinline' attribute is
removed as it does not have any meaning.
Signed-off-by: David Sterba <dsterba@suse.com>
Currently there are 2 function doing binary search on btrfs nodes:
bin_search and btrfs_bin_search. The latter being a simple wrapper for
the former. So eliminate the wrapper and just rename bin_search to
btrfs_bin_search. 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>
The tree argument passed to extent_write_full_page is referenced from
the page being passed to the same function. Since we already have
enough information to get the reference, remove the function parameter.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This function is called only from submit_compressed_extents and the
io tree being passed is always that of the inode. But we are also
passing the inode, so just move getting the io tree pointer in
extent_write_locked_range to simplify the signature.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This code was added in 492bb6deee ("Btrfs: Hold a reference on bios
during submit_bio, add some extra bio checks"). However, holding a
reference on a bio is necessary only if it's going to be referenced
after the submit_bio returns and the bio is completed. In this
particular instance this is not the case so there is no need to hold
an extra reference since we directly return.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When modifying a tree where the root is at BTRFS_MAX_LEVEL - 1 then
the level variable is going to be 7 (this is the max height of the
tree). On the other hand btrfs_cow_block is always called with
"level + 1" as an index into the nodes and slots arrays. This leads to
an out of bounds access. Admittdely this will be benign since an OOB
access of the nodes array will likely read the 0th element from the
slots array, which in this case is going to be 0 (since we start CoW at
the top of the tree). The OOB access into the slots array in turn will
read the 0th and 1st values of the locks array, which would both be 0
at the time. However, this benign behavior relies on the fact that the
path being passed hasn't been initialised, if it has already been used to
query a btree then it could potentially have populated the nodes/slots arrays.
Fix it by explicitly checking if we are at level 7 (the maximum allowed
index in nodes/slots arrays) and explicitly call the CoW routine with
NULL for parent's node/slot.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Fixes-coverity-id: 711515
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
These duplicate includes have been found with scripts/checkincludes.pl but
they have been removed manually to avoid removing false positives.
Signed-off-by: Pravin Shedge <pravin.shedge4linux@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This function was introduced by 247e743cbe ("Btrfs: Use async helpers
to deal with pages that have been improperly dirtied") and it didn't do
any error handling then. This function might very well fail in ENOMEM
situation, yet it's not handled, this could lead to inconsistent state.
So let's handle the failure by setting the mapping error bit.
Cc: stable@vger.kernel.org
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There are several places opencoding this conversion, add a helper now
that we have 3 compression algorithms.
Signed-off-by: David Sterba <dsterba@suse.com>
Before returning hole_em in btrfs_get_fiemap_extent we check if it's different
than null. However, by the time this null check is triggered we already know
hole_em is not null because it means it points to the em we found and it
has already been dereferenced.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
trans was statically assigned to NULL and this never changed over the
course of btrfs_get_extent. So remove any code which checks whether
trans != NULL and just hardcode the fact trans is always NULL.
Resolves-coverity-id: 112806
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The return value of sizeof() is of type size_t, so we must print it
using the %z format modifier rather than %l to avoid this warning
on some architectures:
fs/btrfs/tree-checker.c: In function 'check_dir_item':
fs/btrfs/tree-checker.c:273:50: error: format '%lu' expects argument of type 'long unsigned int', but argument 5 has type 'u32' {aka 'unsigned int'} [-Werror=format=]
Fixes: 005887f2e3e0 ("btrfs: tree-checker: Add checker for dir item")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This changes to use struct completion directly and removes 'struct
scrub_bio_ret' along with the code using it.
This struct is used to get the return value from bio, but the caller can
access bio to get the return value directly and is holding a reference
on it so it won't go away underneath us and can be removed safely.
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>
The defined wait is not used anywhere.
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>
We need to call extent_range_clear_dirty_for_io()
on compression range to prevent application from changing
page content, while pages compressing.
extent_range_clear_dirty_for_io() runs on each loop iteration,
"(end - start)" can be much (up to 1024 times) bigger
then compression range (BTRFS_MAX_UNCOMPRESSED).
The start pointer is advanced each time we manage to compress part of
the range. The end pointer does not change so we could redirty the
remaining parts repeatedly.
Fix that behaviour by call extent_range_clear_dirty_for_io()
only once, the first time it happens.
This is the safest but probably not the best behaviour. Previous
iterations of the patch tried to redirty only the range that we were not
able to compress. This has been refused by David for safety reasons, the
writeout callchain is complex and there could be some path that relies
on redirtying the entire unwritten range.
Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ enhance changelog, the history and safety concerns, add comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
Slowest part of heuristic for now is kernel heap sort()
It's can take up to 55% of runtime on sorting bucket items.
As sorting will always call on most data sets to get correctly
byte_core_set_size, the only way to speed up heuristic, is to
speed up sort on bucket.
Add a general radix_sort function.
Radix sort require 2 buffers, one full size of input array
and one for store counters (jump addresses).
That increase usage per heuristic workspace +1KiB
8KiB + 1KiB -> 8KiB + 2KiB
That is LSD Radix, i use 4 bit as a base for calculating,
to make counters array acceptable small (16 elements * 8 byte).
That Radix sort implementation have several points to adjust,
I added him to make radix sort general usable in kernel,
like heap sort, if needed.
Performance tested in userspace copy of heuristic code,
throughput:
- average <-> random data: ~3500 MiB/s - heap sort
- average <-> random data: ~6000 MiB/s - radix sort
Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>
[ coding style fixes ]
Signed-off-by: David Sterba <dsterba@suse.com>
Currently device state is being managed by each individual int
variable such as struct btrfs_device::is_tgtdev_for_dev_replace.
Instead of that declare btrfs_device::dev_state
BTRFS_DEV_STATE_FLUSH_SENT and use the bit operations.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently device state is being managed by each individual int
variable such as struct btrfs_device::is_tgtdev_for_dev_replace.
Instead of that declare btrfs_device::dev_state
BTRFS_DEV_STATE_MISSING and use the bit operations.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
[ whitespace adjustments ]
Signed-off-by: David Sterba <dsterba@suse.com>
Currently device state is being managed by each individual int
variable such as struct btrfs_device::missing. Instead of that
declare btrfs_device::dev_state BTRFS_DEV_STATE_MISSING and use
the bit operations.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by : Nikolay Borisov <nborisov@suse.com>
[ whitespace adjustments ]
Signed-off-by: David Sterba <dsterba@suse.com>
Currently device state is being managed by each individual int
variable such as struct btrfs_device::in_fs_metadata. Instead of
that declare device state BTRFS_DEV_STATE_IN_FS_METADATA and use
the bit operations.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
[ whitespace adjustments ]
Signed-off-by: David Sterba <dsterba@suse.com>
Currently device state is being managed by each individual int
variable such as struct btrfs_device::writeable. Instead of that
declare device state BTRFS_DEV_STATE_WRITEABLE and use the
bit operations.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
[ whitespace adjustments ]
Signed-off-by: David Sterba <dsterba@suse.com>
This patch creates a helper function to get either the rcu device path
or missing.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
[ rename to btrfs_dev_name, switch to if/else ]
Signed-off-by: David Sterba <dsterba@suse.com>
We can query the bdev directly when needed at btrfs_discard_extent()
so drop btrfs_device::can_discard.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Suggested-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The function update_share_count is local to the source and does
not need to be in global scope, so make it static.
Cleans up sparse warning:
fs/btrfs/backref.c:219:6: warning: symbol 'update_share_count' was not
declared. Should it be static?
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>
Commit 9036c10208 ("Btrfs: update hole handling v2") added the
FLAG_VACANCY to denote holes, however there was already a consistent way
of flagging extents which represent hole - ->block_start =
EXTENT_MAP_HOLE. And also the only place where this flag is checked is
in the fiemap code, but the block_start value is also checked and every
other place in the filesystem detects holes by using block_start
value's. So remove the extra flag. This survived a full xfstest run.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This function is no longer used outside of extent-tree.c.
Make it static.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
* ZSTD_inBuffer in_buf
* ZSTD_outBuffer out_buf
are used in all functions to pass the compression parameters and the
local variables consume some space. We can move them to the workspace
and reduce the stack consumption:
zstd.c:zstd_decompress -24 (136 -> 112)
zstd.c:zstd_decompress_bio -24 (144 -> 120)
zstd.c:zstd_compress_pages -24 (264 -> 240)
Signed-off-by: David Sterba <dsterba@suse.com>
Reviewed-by: Nick Terrell <terrelln@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There are now 20 bytes of holes, we can reduce that to 4 by minor
changes. Moving 'aborted' to the status and flags is also more logical,
similar for num_dirty_bgs. The size goes from 432 to 416.
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Recent updates to the structure left some holes, reorder the types so
the packing is tight. The size goes from 112 to 104 on 64bit.
Signed-off-by: David Sterba <dsterba@suse.com>
The use_count is a reference counter, we can use the refcount_t type,
though we don't use the atomicity. This is not a performance critical
code and we could catch the underflows. The type is changed from long,
but the number of references will fit an int.
Signed-off-by: David Sterba <dsterba@suse.com>
Last user was removed in a monster commit a22285a6a3
("Btrfs: Integrate metadata reservation with start_transaction") in
2010.
Signed-off-by: David Sterba <dsterba@suse.com>
The semantics of adding_csums matches bool, 'short' was most likely used
to save space in a698d0755a ("Btrfs: add a type field for the
transaction handle").
Signed-off-by: David Sterba <dsterba@suse.com>
Due to new_inline logic, the create == 0 is always true at this
point in the code, so the create != 0 branch can be removed.
Signed-off-by: Edmund Nadolski <enadolski@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Replace hardcoded numeric argument values for inode_only with the
constants defined for that use.
Signed-off-by: Edmund Nadolski <enadolski@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The maximum size of a checksum buffer is known, BTRFS_CSUM_SIZE, and we
don't have to allocate it dynamically. This code path is not used at all
as we have only the crc32c and use an on-stack buffer already.
Signed-off-by: David Sterba <dsterba@suse.com>
Setting plug can merge adjacent IOs before dispatching IOs to the disk
driver.
Without plug, it'd not be a problem for single disk usecases, but for
multiple disks using raid profile, a large IO can be split to several
IOs of stripe length, and plug can be helpful to bring them together
for each disk so that we can save several disk access.
Moreover, fsync issues synchronous writes, so plug can really take
effect.
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>
No functional changes, create btrfs_open_one_device() from
__btrfs_open_devices(). This is a preparatory work to add dynamic
device scan.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
[ minor whitespace fixes ]
Signed-off-by: David Sterba <dsterba@suse.com>
No functional changes. This helps to move the entire section into
a new function.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is in preparation to move a section of code in __btrfs_open_devices()
into a new function so that it can be reused. As we set seeding if any of
the device is having SB flag BTRFS_SUPER_FLAG_SEEDING, so do it in the
device list loop itself. No functional changes.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
With gcc-4.1.2:
fs/btrfs/ref-verify.c: In function ‘btrfs_build_ref_tree’:
fs/btrfs/ref-verify.c:1017: warning: ‘root’ is used uninitialized in this function
The variable is indeed passed uninitialized, but it is never used by the
callee. However, not all versions of gcc are smart enough to notice.
Hence remove the unused parameter from walk_up_tree() to silence the
compiler warning.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: David Sterba <dsterba@suse.com>
All callers pass btrfs_get_extent_fiemap and get_extent_skip_holes
itself is used only as a fiemap helper.
Signed-off-by: David Sterba <dsterba@suse.com>
All callers pass btrfs_get_extent_fiemap and we don't expect anything
else in the context of extent_fiemap.
Signed-off-by: David Sterba <dsterba@suse.com>
Previous patches cleaned up all places where
extent_page_data::get_extent was set and it was btrfs_get_extent all the
time, so we can simply call that instead.
This also reduces size of extent_page_data by 8 bytes which has positive
effect on stack consumption on various functions on the write out path.
Signed-off-by: David Sterba <dsterba@suse.com>
Since tree-checker has verified leaf when reading from disk, we don't
need the existing verify_dir_item() or btrfs_is_name_len_valid() checks.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add checker for dir item, for key types DIR_ITEM, DIR_INDEX and
XATTR_ITEM.
This checker does comprehensive checks for:
1) dir_item header and its data size
Against item boundary and maximum name/xattr length.
This part is mostly the same as old verify_dir_item().
2) dir_type
Against maximum file types, and against key type.
Since XATTR key should only have FT_XATTR dir item, and normal dir
item type should not have XATTR key.
The check between key->type and dir_type is newly introduced by this
patch.
3) name hash
For XATTR and DIR_ITEM key, key->offset is name hash (crc32c).
Check the hash of the name against the key to ensure it's correct.
The name hash check is only found in btrfs-progs before this patch.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
All callers use GFP_NOFS, we don't have to pass it as an argument. The
built-in tests pass GFP_KERNEL, but they run only at module load time
and NOFS works there as well.
Signed-off-by: David Sterba <dsterba@suse.com>
Use __clear_extent_bit directly in case we want to pass unknown
gfp flags. Otherwise all clear_extent_bit callers use GFP_NOFS, so we
can sink them to the function and reduce argument count, at the cost
that __clear_extent_bit has to be exported.
Signed-off-by: David Sterba <dsterba@suse.com>
We take the fs_devices::device_list_mutex mutex in write_all_supers
which will prevent any add/del changes to the device list. Therefore we
don't need to use the RCU variant list_for_each_entry_rcu in any of the
called functions.
Signed-off-by: David Sterba <dsterba@suse.com>
We don't need to use the mutex as we do not modify the devices nor the
list itself and just read information about device counts.
Move copying fsid out of the protected section, not applicable to RCU
same as the rest of the retrieved information.
Signed-off-by: David Sterba <dsterba@suse.com>
We don't need to use the mutex as we do not modify the devices nor the
list itself and just read some information:
does not change during device lifetime:
- devid
- uuid
- name (ie. the path)
may change in parallel to the ioctl call, but can lead only to reporting
inacurracy:
- bytes_used
- total_bytes
Signed-off-by: David Sterba <dsterba@suse.com>
A helper to free a device and all it's dynamically allocated members,
like the rcu_string name or flush_bio. This is going to replace all
open coded places.
Signed-off-by: David Sterba <dsterba@suse.com>
Make it clear that it is an RCU helper, we want to use the name
free_device for a wrapper freeing all device members.
Signed-off-by: David Sterba <dsterba@suse.com>
These rules have been hidden in several if-else and are not
straightforward to follow, for example, dio submit hook's nocsum case
has a bug , i.e. doing async submit instead of sync submit, which has
been fixed recently.
This is documenting the rules for reference.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
After commit 996478ca9c ("btrfs: change how we decide to commit
transactions during flushing") there is no need to hold the delayed_rsv
during the percpu_counter_compare call since we get the byte's snapshot
earlier. So hold the lock only while reading delayed_rsv.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Adding __init macro gives kernel a hint that this function is only used
during the initialization phase and its memory resources can be freed up
after.
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>
Function btrfs_add_device() is adding the device item so rename to
reflect that in the function. Similarly we have btrfs_rm_dev_item().
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_create_tree() will unconditionally generate UUID for any root.
So for quota tree and data reloc tree created by kernel, they will have
unique UUIDs.
However UUID in root item is only referred by UUID tree, which only
records UUID for fs trees. This makes unique UUIDs for quota/data reloc
tree meaningless.
Leave the UUID as zero for non-fs tree, making btrfs-debug-tree output
less confusing.
Reported-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
A cleanup patch no functional change, we hold volume_mutex before
calling btrfs_rm_device, so move it into the function itself.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Right before we go into this loop locked_end is set to alloc_end - 1 and
is being used in nearby functions, no need to have exceptions. This just
makes the code consistent, 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>
Fallocating a file in btrfs goes through several stages. The one before
actually inserting the fallocated extents is to create a qgroup
reservation, covering the desired range. To this end there is a loop in
btrfs_fallocate which checks to see if there are holes in the fallocated
range or !PREALLOC extents past EOF and if so create qgroup reservations
for them. Unfortunately, the main condition of the loop is burried right
at the end of its body rather than in the actual while statement which
makes it non-obvious. Fix this by moving the condition in the while
statement where it belongs. 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>
It was introduced because btrfs used to do blkdev_put in a deferred
work, now that btrfs has blkdev_put in place, this rcu_barrier can be
removed.
modprobe -r btrfs will do btrfs_cleanup_fs_uuids(), where it cleanup
every %fs_devices on the list, but when we do btrfs_close_devices(), we
have replaced the devices on the list with dummy ones which only have
the same name and uuid, so modprobe -r btrfs will free those instead of
what we were using, this change won't cause a problem for it.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ copied 2nd paragraph from mailinglist discussion ]
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_balance_delayed_items is the sole caller of
btrfs_wq_run_delayed_node and already includes one of the checks whether
the delayed inodes should be run. On the other hand
btrfs_wq_run_delayed_node duplicates that check and performs an
additional one for wq congestion.
Let's remove the duplicate check and move the congestion one in
btrfs_balance_delayed_items, leaving btrfs_wq_run_delayed_node to only
care about setting up the wq run. No functional changes.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently btrfs_async_run_delayed_root's implementation uses 3 goto
labels to mimic the functionality of a simple do {} while loop. Refactor
the function to use a do {} while construct, making intention clear and
code easier to follow. No functional changes.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The following callpath is always invoked with mirror_num set to 0, so
let's remove it as an argument and directly pass 0 to __do_redpage. No
functional change.
extent_readpages
__extent_readpages
__do_contiguous_readpages
__do_readpage
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
It's sole callsite was removed in a previous patch so just nuke it for good.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
As per atomic_t.txt documentation :
- RMW operations that have a return value are fully ordered;
atomic_xchg is one such operation so it already includes everything it
needs w.r.t memory ordering and add a comment to be more explicit about
that.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Commit addc3fa74e ("Btrfs: Fix the problem that the dirty flag of dev
stats is cleared") reworked the way device stats changes are tracked. A
new atomic dev_stats_ccnt counter was introduced which is incremented
every time any of the device stats counters are changed. This serves as
a flag whether there are any pending stats changes. However, this patch
only partially implemented the correct memory barriers necessary:
- It only ordered the stores to the counters but not the reads e.g.
btrfs_run_dev_stats
- It completely omitted any comments documenting the intended design and
how the memory barriers pair with each-other
This patch provides the necessary comments as well as adds a missing
smp_rmb in btrfs_run_dev_stats. Furthermore since dev_stats_cnt is only
a snapshot at best there was no point in reading the counter twice -
once in btrfs_dev_stats_dirty and then again when assigning stats_cnt.
Just collapse both reads into 1.
Fixes: addc3fa74e ("Btrfs: Fix the problem that the dirty flag of dev stats is cleared")
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_end_bio() is using btrfs_dev_stat_inc() and then
btrfs_dev_stat_print_on_error() separately instead use
btrfs_dev_stat_inc_and_print() directly.
As of now there isn't any bio in btrfs which is - a non-empty write and
also the REQ_PREFLUSH flag is set. So in actual the condition
if (bio->bi_opf & REQ_PREFLUSH)
is never true in btrfs_end_bio(), and so there won't be any redundant
error log by using btrfs_dev_stat_inc_and_print() separately one for
write and another for flush.
This consolidation will help to add the device critical error handles in
the function btrfs_dev_stat_inc_and_print() and which can be renamed as
needed.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
It's pointless to defer it to a kthread helper as we're not under a
special context.
For reference, commit 1f78160ce1 ("Btrfs: using rcu lock in the reader
side of devices list") introduced RCU freeing for device structures.
Originally the blkdev_put was called from free_device and rcu_barrier had
to be called. This is no longer required, bdev and our device structures
are now freed separately.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ enhance changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
In functions like btrfs_create(), we run both
btrfs_balance_delayed_items() and btrfs_btree_balance_dirty() after
the operation, but btrfs_btree_balance_dirty() is surely going to run
btrfs_balance_delayed_items().
This keeps only btrfs_btree_balance_dirty().
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add injectable error types for each error-injectable function.
One motivation of error injection test is to find software flaws,
mistakes or mis-handlings of expectable errors. If we find such
flaws by the test, that is a program bug, so we need to fix it.
But if the tester miss input the error (e.g. just return success
code without processing anything), it causes unexpected behavior
even if the caller is correctly programmed to handle any errors.
That is not what we want to test by error injection.
To clarify what type of errors the caller must expect for each
injectable function, this introduces injectable error types:
- EI_ETYPE_NULL : means the function will return NULL if it
fails. No ERR_PTR, just a NULL.
- EI_ETYPE_ERRNO : means the function will return -ERRNO
if it fails.
- EI_ETYPE_ERRNO_NULL : means the function will return -ERRNO
(ERR_PTR) or NULL.
ALLOW_ERROR_INJECTION() macro is expanded to get one of
NULL, ERRNO, ERRNO_NULL to record the error type for
each function. e.g.
ALLOW_ERROR_INJECTION(open_ctree, ERRNO)
This error types are shown in debugfs as below.
====
/ # cat /sys/kernel/debug/error_injection/list
open_ctree [btrfs] ERRNO
io_ctl_init [btrfs] ERRNO
====
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Since error-injection framework is not limited to be used
by kprobes, nor bpf. Other kernel subsystems can use it
freely for checking safeness of error-injection, e.g.
livepatch, ftrace etc.
So this separate error-injection framework from kprobes.
Some differences has been made:
- "kprobe" word is removed from any APIs/structures.
- BPF_ALLOW_ERROR_INJECTION() is renamed to
ALLOW_ERROR_INJECTION() since it is not limited for BPF too.
- CONFIG_FUNCTION_ERROR_INJECTION is the config item of this
feature. It is automatically enabled if the arch supports
error injection feature for kprobe or ftrace etc.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Commit 17347cec15f919901c90(Btrfs: change how we iterate bios in endio)
mentioned that for dio the submitted bio may be fast cloned, we
can't access the bvec table directly for a cloned bio, so use
bio_get_first_bvec() to retrieve the 1st bvec.
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: David Sterba <dsterba@suse.com>
Cc: linux-btrfs@vger.kernel.org
Cc: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Acked: David Sterba <dsterba@suse.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
BTRFS uses bio->bi_vcnt to figure out page numbers, this approach is no
longer valid once we start enabling multipage bvecs.
correct once we start to enable multipage bvec.
Use bio_nr_pages() to do that instead.
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: David Sterba <dsterba@suse.com>
Cc: linux-btrfs@vger.kernel.org
Acked-by: David Sterba <dsterba@suse.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This patch converts 3 users to bio_last_bvec_all(), so that we can go
ahead and convert to multipage bvec.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This patch converts to bio_first_bvec_all() & bio_first_page_all() for
retrieving the 1st bvec/page, and prepares for supporting multipage bvec.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Merge tag 'for-4.15-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
"We have two more fixes for 4.15, both aimed for stable.
The leak fix is obvious, the second patch fixes a bug revealed by the
refcount API, when it behaves differently than previous atomic_t and
reports refs going from 0 to 1 in one case"
* tag 'for-4.15-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: fix refcount_t usage when deleting btrfs_delayed_nodes
btrfs: Fix flush bio leak
refcounts have a generic implementation and an asm optimized one. The
generic version has extra debugging to make sure that once a refcount
goes to zero, refcount_inc won't increase it.
The btrfs delayed inode code wasn't expecting this, and we're tripping
over the warnings when the generic refcounts are used. We ended up with
this race:
Process A Process B
btrfs_get_delayed_node()
spin_lock(root->inode_lock)
radix_tree_lookup()
__btrfs_release_delayed_node()
refcount_dec_and_test(&delayed_node->refs)
our refcount is now zero
refcount_add(2) <---
warning here, refcount
unchanged
spin_lock(root->inode_lock)
radix_tree_delete()
With the generic refcounts, we actually warn again when process B above
tries to release his refcount because refcount_add() turned into a
no-op.
We saw this in production on older kernels without the asm optimized
refcounts.
The fix used here is to use refcount_inc_not_zero() to detect when the
object is in the middle of being freed and return NULL. This is almost
always the right answer anyway, since we usually end up pitching the
delayed_node if it didn't have fresh data in it.
This also changes __btrfs_release_delayed_node() to remove the extra
check for zero refcounts before radix tree deletion.
btrfs_get_delayed_node() was the only path that was allowing refcounts
to go from zero to one.
Fixes: 6de5f18e7b ("btrfs: fix refcount_t usage when deleting btrfs_delayed_node")
CC: <stable@vger.kernel.org> # 4.12+
Signed-off-by: Chris Mason <clm@fb.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Commit e0ae999414 ("btrfs: preallocate device flush bio") reworked
the way the flush bio is allocated and used. Concretely it allocates
the bio in __alloc_device and then re-uses it multiple times with a
very simple endio routine that just calls complete() without consuming
a reference. Allocated bios by default come with a ref count of 1,
which is then consumed by the endio routine (or not, in which case they
should be bio_put by the caller). The way the impleementation works now
is that the flush bio has a refcount of 2 and we only ever bio_put it
once, leaving it to hang indefinitely. Fix this by removing the extra
bio_get in __alloc_device.
Fixes: e0ae999414 ("btrfs: preallocate device flush bio")
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This link is replicated in most filesystems' config stanzas. Referring
to an archived version of that site is pointless as it mostly deals with
patches; user documentation is available elsewhere.
Signed-off-by: Adam Borowski <kilobyte@angband.pl>
CC: Alexander Viro <viro@zeniv.linux.org.uk>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Jan Kara <jack@suse.cz>
Acked-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Acked-by: David Sterba <dsterba@suse.com>
Acked-by: "Yan, Zheng" <zyan@redhat.com>
Acked-by: Chao Yu <yuchao0@huawei.com>
Acked-by: Jaegeuk Kim <jaegeuk@kernel.org>
Acked-by: Steve French <smfrench@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Daniel Borkmann says:
====================
pull-request: bpf-next 2017-12-18
The following pull-request contains BPF updates for your *net-next* tree.
The main changes are:
1) Allow arbitrary function calls from one BPF function to another BPF function.
As of today when writing BPF programs, __always_inline had to be used in
the BPF C programs for all functions, unnecessarily causing LLVM to inflate
code size. Handle this more naturally with support for BPF to BPF calls
such that this __always_inline restriction can be overcome. As a result,
it allows for better optimized code and finally enables to introduce core
BPF libraries in the future that can be reused out of different projects.
x86 and arm64 JIT support was added as well, from Alexei.
2) Add infrastructure for tagging functions as error injectable and allow for
BPF to return arbitrary error values when BPF is attached via kprobes on
those. This way of injecting errors generically eases testing and debugging
without having to recompile or restart the kernel. Tags for opting-in for
this facility are added with BPF_ALLOW_ERROR_INJECTION(), from Josef.
3) For BPF offload via nfp JIT, add support for bpf_xdp_adjust_head() helper
call for XDP programs. First part of this work adds handling of BPF
capabilities included in the firmware, and the later patches add support
to the nfp verifier part and JIT as well as some small optimizations,
from Jakub.
4) The bpftool now also gets support for basic cgroup BPF operations such
as attaching, detaching and listing current BPF programs. As a requirement
for the attach part, bpftool can now also load object files through
'bpftool prog load'. This reuses libbpf which we have in the kernel tree
as well. bpftool-cgroup man page is added along with it, from Roman.
5) Back then commit e87c6bc385 ("bpf: permit multiple bpf attachments for
a single perf event") added support for attaching multiple BPF programs
to a single perf event. Given they are configured through perf's ioctl()
interface, the interface has been extended with a PERF_EVENT_IOC_QUERY_BPF
command in this work in order to return an array of one or multiple BPF
prog ids that are currently attached, from Yonghong.
6) Various minor fixes and cleanups to the bpftool's Makefile as well
as a new 'uninstall' and 'doc-uninstall' target for removing bpftool
itself or prior installed documentation related to it, from Quentin.
7) Add CONFIG_CGROUP_BPF=y to the BPF kernel selftest config file which is
required for the test_dev_cgroup test case to run, from Naresh.
8) Fix reporting of XDP prog_flags for nfp driver, from Jakub.
9) Fix libbpf's exit code from the Makefile when libelf was not found in
the system, also from Jakub.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This was instrumental in reproducing a space cache bug.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This allows us to do error injection with BPF for open_ctree.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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Merge tag 'for-4.15-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
"This contains a few fixes (error handling, quota leak, FUA vs
nobarrier mount option).
There's one one worth mentioning separately - an off-by-one fix that
leads to overwriting first byte of an adjacent page with 0, out of
bounds of the memory allocated by an ioctl. This is under a privileged
part of the ioctl, can be triggerd in some subvolume layouts"
* tag 'for-4.15-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: Fix possible off-by-one in btrfs_search_path_in_tree
Btrfs: disable FUA if mounted with nobarrier
btrfs: fix missing error return in btrfs_drop_snapshot
btrfs: handle errors while updating refcounts in update_ref_for_cow
btrfs: Fix quota reservation leak on preallocated files
The name char array passed to btrfs_search_path_in_tree is of size
BTRFS_INO_LOOKUP_PATH_MAX (4080). So the actual accessible char indexes
are in the range of [0, 4079]. Currently the code uses the define but this
represents an off-by-one.
Implications:
Size of btrfs_ioctl_ino_lookup_args is 4096, so the new byte will be
written to extra space, not some padding that could be provided by the
allocator.
btrfs-progs store the arguments on stack, but kernel does own copy of
the ioctl buffer and the off-by-one overwrite does not affect userspace,
but the ending 0 might be lost.
Kernel ioctl buffer is allocated dynamically so we're overwriting
somebody else's memory, and the ioctl is privileged if args.objectid is
not 256. Which is in most cases, but resolving a subvolume stored in
another directory will trigger that path.
Before this patch the buffer was one byte larger, but then the -1 was
not added.
Fixes: ac8e9819d7 ("Btrfs: add search and inode lookup ioctls")
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ added implications ]
Signed-off-by: David Sterba <dsterba@suse.com>
I was seeing disk flushes still happening when I mounted a Btrfs
filesystem with nobarrier for testing. This is because we use FUA to
write out the first super block, and on devices without FUA support, the
block layer translates FUA to a flush. Even on devices supporting true
FUA, using FUA when we asked for no barriers is surprising.
Fixes: 387125fc72 ("Btrfs: fix barrier flushes")
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
If btrfs_del_root fails in btrfs_drop_snapshot, we'll pick up the
error but then return 0 anyway due to mixing err and ret.
Fixes: 79787eaab4 ("btrfs: replace many BUG_ONs with proper error handling")
Cc: <stable@vger.kernel.org> # v3.4+
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Since commit fb235dc06f (btrfs: qgroup: Move half of the qgroup
accounting time out of commit trans) the assumption that
btrfs_add_delayed_{data,tree}_ref can only return 0 or -ENOMEM has
been false. The qgroup operations call into btrfs_search_slot
and friends and can now return the full spectrum of error codes.
Fortunately, the fix here is easy since update_ref_for_cow failing
is already handled so we just need to bail early with the error
code.
Fixes: fb235dc06f (btrfs: qgroup: Move half of the qgroup accounting ...)
Cc: <stable@vger.kernel.org> # v4.11+
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: Edmund Nadolski <enadolski@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Commit c6887cd111 ("Btrfs: don't do nocow check unless we have to")
changed the behavior of __btrfs_buffered_write() so that it first tries
to get a data space reservation, and then skips the relatively expensive
nocow check if the reservation succeeded.
If we have quotas enabled, the data space reservation also includes a
quota reservation. But in the rewrite case, the space has already been
accounted for in qgroups. So btrfs_check_data_free_space() increases
the quota reservation, but it never gets decreased when the data
actually gets written and overwrites the pre-existing data. So we're
left with both the qgroup and qgroup reservation accounting for the same
space.
This commit adds the missing btrfs_qgroup_free_data() call in the case
of BTRFS_ORDERED_PREALLOC extents.
Fixes: c6887cd111 ("Btrfs: don't do nocow check unless we have to")
Signed-off-by: Justin Maggard <jmaggard@netgear.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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Merge tag 'for-4.15-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
"We've collected some fixes in since the pre-merge window freeze.
There's technically only one regression fix for 4.15, but the rest
seems important and candidates for stable.
- fix missing flush bio puts in error cases (is serious, but rarely
happens)
- fix reporting stat::st_blocks for buffered append writes
- fix space cache invalidation
- fix out of bound memory access when setting zlib level
- fix potential memory corruption when fsync fails in the middle
- fix crash in integrity checker
- incremetnal send fix, path mixup for certain unlink/rename
combination
- pass flags to writeback so compressed writes can be throttled
properly
- error handling fixes"
* tag 'for-4.15-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
Btrfs: incremental send, fix wrong unlink path after renaming file
btrfs: tree-checker: Fix false panic for sanity test
Btrfs: fix list_add corruption and soft lockups in fsync
btrfs: Fix wild memory access in compression level parser
btrfs: fix deadlock when writing out space cache
btrfs: clear space cache inode generation always
Btrfs: fix reported number of inode blocks after buffered append writes
Btrfs: move definition of the function btrfs_find_new_delalloc_bytes
Btrfs: bail out gracefully rather than BUG_ON
btrfs: dev_alloc_list is not protected by RCU, use normal list_del
btrfs: add missing device::flush_bio puts
btrfs: Fix transaction abort during failure in btrfs_rm_dev_item
Btrfs: add write_flags for compression bio
Under some circumstances, an incremental send operation can issue wrong
paths for unlink commands related to files that have multiple hard links
and some (or all) of those links were renamed between the parent and send
snapshots. Consider the following example:
Parent snapshot
. (ino 256)
|---- a/ (ino 257)
| |---- b/ (ino 259)
| | |---- c/ (ino 260)
| | |---- f2 (ino 261)
| |
| |---- f2l1 (ino 261)
|
|---- d/ (ino 262)
|---- f1l1_2 (ino 258)
|---- f2l2 (ino 261)
|---- f1_2 (ino 258)
Send snapshot
. (ino 256)
|---- a/ (ino 257)
| |---- f2l1/ (ino 263)
| |---- b2/ (ino 259)
| |---- c/ (ino 260)
| | |---- d3 (ino 262)
| | |---- f1l1_2 (ino 258)
| | |---- f2l2_2 (ino 261)
| | |---- f1_2 (ino 258)
| |
| |---- f2 (ino 261)
| |---- f1l2 (ino 258)
|
|---- d (ino 261)
When computing the incremental send stream the following steps happen:
1) When processing inode 261, a rename operation is issued that renames
inode 262, which currently as a path of "d", to an orphan name of
"o262-7-0". This is done because in the send snapshot, inode 261 has
of its hard links with a path of "d" as well.
2) Two link operations are issued that create the new hard links for
inode 261, whose names are "d" and "f2l2_2", at paths "/" and
"o262-7-0/" respectively.
3) Still while processing inode 261, unlink operations are issued to
remove the old hard links of inode 261, with names "f2l1" and "f2l2",
at paths "a/" and "d/". However path "d/" does not correspond anymore
to the directory inode 262 but corresponds instead to a hard link of
inode 261 (link command issued in the previous step). This makes the
receiver fail with a ENOTDIR error when attempting the unlink
operation.
The problem happens because before sending the unlink operation, we failed
to detect that inode 262 was one of ancestors for inode 261 in the parent
snapshot, and therefore we didn't recompute the path for inode 262 before
issuing the unlink operation for the link named "f2l2" of inode 262. The
detection failed because the function "is_ancestor()" only follows the
first hard link it finds for an inode instead of all of its hard links
(as it was originally created for being used with directories only, for
which only one hard link exists). So fix this by making "is_ancestor()"
follow all hard links of the input inode.
A test case for fstests follows soon.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[BUG]
If we run btrfs with CONFIG_BTRFS_FS_RUN_SANITY_TESTS=y, it will
instantly cause kernel panic like:
------
...
assertion failed: 0, file: fs/btrfs/disk-io.c, line: 3853
...
Call Trace:
btrfs_mark_buffer_dirty+0x187/0x1f0 [btrfs]
setup_items_for_insert+0x385/0x650 [btrfs]
__btrfs_drop_extents+0x129a/0x1870 [btrfs]
...
-----
[Cause]
Btrfs will call btrfs_check_leaf() in btrfs_mark_buffer_dirty() to check
if the leaf is valid with CONFIG_BTRFS_FS_RUN_SANITY_TESTS=y.
However quite some btrfs_mark_buffer_dirty() callers(*) don't really
initialize its item data but only initialize its item pointers, leaving
item data uninitialized.
This makes tree-checker catch uninitialized data as error, causing
such panic.
*: These callers include but not limited to
setup_items_for_insert()
btrfs_split_item()
btrfs_expand_item()
[Fix]
Add a new parameter @check_item_data to btrfs_check_leaf().
With @check_item_data set to false, item data check will be skipped and
fallback to old btrfs_check_leaf() behavior.
So we can still get early warning if we screw up item pointers, and
avoid false panic.
Cc: Filipe Manana <fdmanana@gmail.com>
Reported-by: Lakshmipathi.G <lakshmipathi.g@gmail.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is a pure automated search-and-replace of the internal kernel
superblock flags.
The s_flags are now called SB_*, with the names and the values for the
moment mirroring the MS_* flags that they're equivalent to.
Note how the MS_xyz flags are the ones passed to the mount system call,
while the SB_xyz flags are what we then use in sb->s_flags.
The script to do this was:
# places to look in; re security/*: it generally should *not* be
# touched (that stuff parses mount(2) arguments directly), but
# there are two places where we really deal with superblock flags.
FILES="drivers/mtd drivers/staging/lustre fs ipc mm \
include/linux/fs.h include/uapi/linux/bfs_fs.h \
security/apparmor/apparmorfs.c security/apparmor/include/lib.h"
# the list of MS_... constants
SYMS="RDONLY NOSUID NODEV NOEXEC SYNCHRONOUS REMOUNT MANDLOCK \
DIRSYNC NOATIME NODIRATIME BIND MOVE REC VERBOSE SILENT \
POSIXACL UNBINDABLE PRIVATE SLAVE SHARED RELATIME KERNMOUNT \
I_VERSION STRICTATIME LAZYTIME SUBMOUNT NOREMOTELOCK NOSEC BORN \
ACTIVE NOUSER"
SED_PROG=
for i in $SYMS; do SED_PROG="$SED_PROG -e s/MS_$i/SB_$i/g"; done
# we want files that contain at least one of MS_...,
# with fs/namespace.c and fs/pnode.c excluded.
L=$(for i in $SYMS; do git grep -w -l MS_$i $FILES; done| sort|uniq|grep -v '^fs/namespace.c'|grep -v '^fs/pnode.c')
for f in $L; do sed -i $f $SED_PROG; done
Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Xfstests btrfs/146 revealed this corruption,
[ 58.138831] Buffer I/O error on dev dm-0, logical block 2621424, async page read
[ 58.151233] BTRFS error (device sdf): bdev /dev/mapper/error-test errs: wr 1, rd 0, flush 0, corrupt 0, gen 0
[ 58.152403] list_add corruption. prev->next should be next (ffff88005e6775d8), but was ffffc9000189be88. (prev=ffffc9000189be88).
[ 58.153518] ------------[ cut here ]------------
[ 58.153892] WARNING: CPU: 1 PID: 1287 at lib/list_debug.c:31 __list_add_valid+0x169/0x1f0
...
[ 58.157379] RIP: 0010:__list_add_valid+0x169/0x1f0
...
[ 58.161956] Call Trace:
[ 58.162264] btrfs_log_inode_parent+0x5bd/0xfb0 [btrfs]
[ 58.163583] btrfs_log_dentry_safe+0x60/0x80 [btrfs]
[ 58.164003] btrfs_sync_file+0x4c2/0x6f0 [btrfs]
[ 58.164393] vfs_fsync_range+0x5f/0xd0
[ 58.164898] do_fsync+0x5a/0x90
[ 58.165170] SyS_fsync+0x10/0x20
[ 58.165395] entry_SYSCALL_64_fastpath+0x1f/0xbe
...
It turns out that we could record btrfs_log_ctx:io_err in
log_one_extents when IO fails, but make log_one_extents() return '0'
instead of -EIO, so the IO error is not acknowledged by the callers,
i.e. btrfs_log_inode_parent(), which would remove btrfs_log_ctx:list
from list head 'root->log_ctxs'. Since btrfs_log_ctx is allocated
from stack memory, it'd get freed with a object alive on the
list. then a future list_add will throw the above warning.
This returns the correct error in the above case.
Jeff also reported this while testing against his fsync error
patch set[1].
[1]: https://www.spinics.net/lists/linux-btrfs/msg65308.html
"btrfs list corruption and soft lockups while testing writeback error handling"
Fixes: 8407f55326 ("Btrfs: fix data corruption after fast fsync and writeback error")
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>
[BUG]
Kernel panic when mounting with "-o compress" mount option.
KASAN will report like:
------
==================================================================
BUG: KASAN: wild-memory-access in strncmp+0x31/0xc0
Read of size 1 at addr d86735fce994f800 by task mount/662
...
Call Trace:
dump_stack+0xe3/0x175
kasan_report+0x163/0x370
__asan_load1+0x47/0x50
strncmp+0x31/0xc0
btrfs_compress_str2level+0x20/0x70 [btrfs]
btrfs_parse_options+0xff4/0x1870 [btrfs]
open_ctree+0x2679/0x49f0 [btrfs]
btrfs_mount+0x1b7f/0x1d30 [btrfs]
mount_fs+0x49/0x190
vfs_kern_mount.part.29+0xba/0x280
vfs_kern_mount+0x13/0x20
btrfs_mount+0x31e/0x1d30 [btrfs]
mount_fs+0x49/0x190
vfs_kern_mount.part.29+0xba/0x280
do_mount+0xaad/0x1a00
SyS_mount+0x98/0xe0
entry_SYSCALL_64_fastpath+0x1f/0xbe
------
[Cause]
For 'compress' and 'compress_force' options, its token doesn't expect
any parameter so its args[0] contains uninitialized data.
Accessing args[0] will cause above wild memory access.
[Fix]
For Opt_compress and Opt_compress_force, set compression level to
the default.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ set the default in advance ]
Signed-off-by: David Sterba <dsterba@suse.com>
If we fail to prepare our pages for whatever reason (out of memory in
our case) we need to make sure to drop the block_group->data_rwsem,
otherwise hilarity ensues.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add label and use existing unlocking code ]
Signed-off-by: David Sterba <dsterba@suse.com>
We discovered a box that had double allocations, and suspected the space
cache may be to blame. While auditing the write out path I noticed that
if we've already setup the space cache we will just carry on. This
means that any error we hit after cache_save_setup before we go to
actually write the cache out we won't reset the inode generation, so
whatever was already written will be considered correct, except it'll be
stale. Fix this by _always_ resetting the generation on the block group
inode, this way we only ever have valid or invalid cache.
With this patch I was no longer able to reproduce cache corruption with
dm-log-writes and my bpf error injection tool.
Cc: stable@vger.kernel.org
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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Merge tag 'afs-next-20171113' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
Pull AFS updates from David Howells:
"kAFS filesystem driver overhaul.
The major points of the overhaul are:
(1) Preliminary groundwork is laid for supporting network-namespacing
of kAFS. The remainder of the namespacing work requires some way
to pass namespace information to submounts triggered by an
automount. This requires something like the mount overhaul that's
in progress.
(2) sockaddr_rxrpc is used in preference to in_addr for holding
addresses internally and add support for talking to the YFS VL
server. With this, kAFS can do everything over IPv6 as well as
IPv4 if it's talking to servers that support it.
(3) Callback handling is overhauled to be generally passive rather
than active. 'Callbacks' are promises by the server to tell us
about data and metadata changes. Callbacks are now checked when
we next touch an inode rather than actively going and looking for
it where possible.
(4) File access permit caching is overhauled to store the caching
information per-inode rather than per-directory, shared over
subordinate files. Whilst older AFS servers only allow ACLs on
directories (shared to the files in that directory), newer AFS
servers break that restriction.
To improve memory usage and to make it easier to do mass-key
removal, permit combinations are cached and shared.
(5) Cell database management is overhauled to allow lighter locks to
be used and to make cell records autonomous state machines that
look after getting their own DNS records and cleaning themselves
up, in particular preventing races in acquiring and relinquishing
the fscache token for the cell.
(6) Volume caching is overhauled. The afs_vlocation record is got rid
of to simplify things and the superblock is now keyed on the cell
and the numeric volume ID only. The volume record is tied to a
superblock and normal superblock management is used to mediate
the lifetime of the volume fscache token.
(7) File server record caching is overhauled to make server records
independent of cells and volumes. A server can be in multiple
cells (in such a case, the administrator must make sure that the
VL services for all cells correctly reflect the volumes shared
between those cells).
Server records are now indexed using the UUID of the server
rather than the address since a server can have multiple
addresses.
(8) File server rotation is overhauled to handle VMOVED, VBUSY (and
similar), VOFFLINE and VNOVOL indications and to handle rotation
both of servers and addresses of those servers. The rotation will
also wait and retry if the server says it is busy.
(9) Data writeback is overhauled. Each inode no longer stores a list
of modified sections tagged with the key that authorised it in
favour of noting the modified region of a page in page->private
and storing a list of keys that made modifications in the inode.
This simplifies things and allows other keys to be used to
actually write to the server if a key that made a modification
becomes useless.
(10) Writable mmap() is implemented. This allows a kernel to be build
entirely on AFS.
Note that Pre AFS-3.4 servers are no longer supported, though this can
be added back if necessary (AFS-3.4 was released in 1998)"
* tag 'afs-next-20171113' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: (35 commits)
afs: Protect call->state changes against signals
afs: Trace page dirty/clean
afs: Implement shared-writeable mmap
afs: Get rid of the afs_writeback record
afs: Introduce a file-private data record
afs: Use a dynamic port if 7001 is in use
afs: Fix directory read/modify race
afs: Trace the sending of pages
afs: Trace the initiation and completion of client calls
afs: Fix documentation on # vs % prefix in mount source specification
afs: Fix total-length calculation for multiple-page send
afs: Only progress call state at end of Tx phase from rxrpc callback
afs: Make use of the YFS service upgrade to fully support IPv6
afs: Overhaul volume and server record caching and fileserver rotation
afs: Move server rotation code into its own file
afs: Add an address list concept
afs: Overhaul cell database management
afs: Overhaul permit caching
afs: Overhaul the callback handling
afs: Rename struct afs_call server member to cm_server
...
Every pagevec_init user claims the pages being released are hot even in
cases where it is unlikely the pages are hot. As no one cares about the
hotness of pages being released to the allocator, just ditch the
parameter.
No performance impact is expected as the overhead is marginal. The
parameter is removed simply because it is a bit stupid to have a useless
parameter copied everywhere.
Link: http://lkml.kernel.org/r/20171018075952.10627-6-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
All users of pagevec_lookup() and pagevec_lookup_range() now pass
PAGEVEC_SIZE as a desired number of pages. Just drop the argument.
Link: http://lkml.kernel.org/r/20171009151359.31984-15-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We want only pages from given range in btree_write_cache_pages() and
extent_write_cache_pages(). Use pagevec_lookup_range_tag() instead of
pagevec_lookup_tag() and remove unnecessary code.
Link: http://lkml.kernel.org/r/20171009151359.31984-3-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: David Sterba <dsterba@suse.com>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: David Sterba <dsterba@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The patch from commit a7e3b975a0 ("Btrfs: fix reported number of inode
blocks") introduced a regression where if we do a buffered write starting
at position equal to or greater than the file's size and then stat(2) the
file before writeback is triggered, the number of used blocks does not
change (unless there's a prealloc/unwritten extent). Example:
$ xfs_io -f -c "pwrite -S 0xab 0 64K" foobar
$ du -h foobar
0 foobar
$ sync
$ du -h foobar
64K foobar
The first version of that patch didn't had this regression and the second
version, which was the one committed, was made only to address some
performance regression detected by the intel test robots using fs_mark.
This fixes the regression by setting the new delaloc bit in the range, and
doing it at btrfs_dirty_pages() while setting the regular dealloc bit as
well, so that this way we set both bits at once avoiding navigation of the
inode's io tree twice. Doing it at btrfs_dirty_pages() is also the most
meaninful place, as we should set the new dellaloc bit when if we set the
delalloc bit, which happens only if we copied bytes into the pages at
__btrfs_buffered_write().
This was making some of LTP's du tests fail, which can be quickly run
using a command line like the following:
$ ./runltp -q -p -l /ltp.log -f commands -s du -d /mnt
Fixes: a7e3b975a0 ("Btrfs: fix reported number of inode blocks")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Move the definition of the function btrfs_find_new_delalloc_bytes() closer
to the function btrfs_dirty_pages(), because in a future commit it will be
used exclusively by btrfs_dirty_pages(). This just moves the function's
definition, with no functional changes at all.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
If a file's DIR_ITEM key is invalid (due to memory errors) and gets
written to disk, a future lookup_path can end up with kernel panic due
to BUG_ON().
This gets rid of the BUG_ON(), meanwhile output the corrupted key and
return ENOENT if it's invalid.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reported-by: Guillaume Bouchard <bouchard@mercs-eng.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The dev_alloc_list list could be protected by various mutexes,
depending on the context. The list tracks devices that can take part of
allocating new chunks, so the closest mutex is chunk_mutex. Adding a new
device from inside the ADD_DEV ioctl will need device_list_mutex and
registering a new device from the ioctl needs uuid_mutex.
All mutexes naturally guarantee exclusivity against the same context.
The device ownership can move between the contexts and the exclusivity
is guaranteed by other means, eg. during the mount with the uuid_mutex.
There's no RCU involved for dev_alloc_list.
Signed-off-by: David Sterba <dsterba@suse.com>
This fixes potential bio leaks, in several error paths. Unfortunatelly
the device structure freeing is opencoded in many places and I missed
them when introducing the flush_bio.
Most of the time, devices get freed through call_rcu(..., free_device),
so it at least it's not that easy to hit the leak, but it's still
possible through the path that frees stale devices.
Fixes: e0ae999414 ("btrfs: preallocate device flush bio")
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_rm_dev_item calls several function under an active transaction,
however it fails to abort it if an error happens. Fix this by adding
explicit btrfs_abort_transaction/btrfs_end_transaction calls.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Compression code path has only flaged bios with REQ_OP_WRITE no matter
where the bios come from, but it could be a sync write if fsync starts
this writeback or a normal writeback write if wb kthread starts a
periodic writeback.
It breaks the rule that sync writes and writeback writes need to be
differentiated from each other, because from the POV of block layer,
all bios need to be recognized by these flags in order to do some
management, e.g. throttlling.
This passes writeback_control to compression write path so that it can
send bios with proper flags to block layer.
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>
Pull btrfs updates from David Sterba:
"There are some new user features and the usual load of invisible
enhancements or cleanups.
New features:
- extend mount options to specify zlib compression level, -o
compress=zlib:9
- v2 of ioctl "extent to inode mapping", addressing a usecase where
we want to retrieve more but inaccurate results and do the
postprocessing in userspace, aiding defragmentation or
deduplication tools
- populate compression heuristics logic, do data sampling and try to
guess compressibility by: looking for repeated patterns, counting
unique byte values and distribution, calculating Shannon entropy;
this will need more benchmarking and possibly fine tuning, but the
base should be good enough
- enable indexing for btrfs as lower filesystem in overlayfs
- speedup page cache readahead during send on large files
Internal enhancements:
- more sanity checks of b-tree items when reading them from disk
- more EINVAL/EUCLEAN fixups, missing BLK_STS_* conversion, other
errno or error handling fixes
- remove some homegrown IO-related logic, that's been obsoleted by
core block layer changes (batching, plug/unplug, own counters)
- add ref-verify, optional debugging feature to verify extent
reference accounting
- simplify code handling outstanding extents, make it more clear
where and how the accounting is done
- make delalloc reservations per-inode, simplify the code and make
the logic more straightforward
- extensive cleanup of delayed refs code
Notable fixes:
- fix send ioctl on 32bit with 64bit kernel"
* 'for-4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (102 commits)
btrfs: Fix bug for misused dev_t when lookup in dev state hash table.
Btrfs: heuristic: add Shannon entropy calculation
Btrfs: heuristic: add byte core set calculation
Btrfs: heuristic: add byte set calculation
Btrfs: heuristic: add detection of repeated data patterns
Btrfs: heuristic: implement sampling logic
Btrfs: heuristic: add bucket and sample counters and other defines
Btrfs: compression: separate heuristic/compression workspaces
btrfs: move btrfs_truncate_block out of trans handle
btrfs: don't call btrfs_start_delalloc_roots in flushoncommit
btrfs: track refs in a rb_tree instead of a list
btrfs: add a comp_refs() helper
btrfs: switch args for comp_*_refs
btrfs: make the delalloc block rsv per inode
btrfs: add tracepoints for outstanding extents mods
Btrfs: rework outstanding_extents
btrfs: increase output size for LOGICAL_INO_V2 ioctl
btrfs: add a flags argument to LOGICAL_INO and call it LOGICAL_INO_V2
btrfs: add a flag to iterate_inodes_from_logical to find all extent refs for uncompressed extents
btrfs: send: remove unused code
...
Make wait_on_atomic_t() pass the TASK_* mode onto its action function as an
extra argument and make it 'unsigned int throughout.
Also, consolidate a bunch of identical action functions into a default
function that can do the appropriate thing for the mode.
Also, change the argument name in the bit_wait*() function declarations to
reflect the fact that it's the mode and not the bit number.
[Peter Z gives this a grudging ACK, but thinks that the whole atomic_t wait
should be done differently, though he's not immediately sure as to how]
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
cc: Ingo Molnar <mingo@kernel.org>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix bug of commit 74d46992e0 ("block: replace bi_bdev with a gendisk
pointer and partitions index").
bio_dev(bio) is used to find the dev state in function
__btrfsic_submit_bio. But when dev_state is added to the hashtable, it
is using dev_t of block_device.
bio_dev(bio) returns a dev_t of part0 which is different from dev_t in
block_device(bd_dev). bd_dev in block_device represents the exact
partition.
block_device.bd_dev =
bio->bi_partno (same as block_device.bd_partno) + bio_dev(bio).
When adding a dev_state into hashtable, we use the exact partition dev_t.
So when looking it up, it should also use the exact partition dev_t.
Reproducer of this bug:
Use MOUNT_OPTIONS="-o check_int" and run btrfs/001 in fstests.
Then there will be WARNING like below.
WARNING:
btrfs: attempt to write superblock which references block M @29523968 (sda7 /1111654400/2) which is never written!
Signed-off-by: Gu JinXiang <gujx@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Byte distribution check in heuristic will filter edge data cases and
some time fail to classify input data.
Let's fix that by adding Shannon entropy calculation, that will cover
classification of most other data types.
As Shannon entropy needs log2 with some precision to work, let's use
ilog2(N) and for increased precision, by do ilog2(pow(N, 4)).
Shannon entropy has been slightly changed to avoid signed numbers and
division.
The calculation is direct by the formula, successor of precalculated
table or chains of if-else.
The accuracy errors of ilog2 are compensated by
@ENTROPY_LVL_ACEPTABLE 70 -> 65
@ENTROPY_LVL_HIGH 85 -> 80
Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update comments ]
Signed-off-by: David Sterba <dsterba@suse.com>
Calculate byte core set for data sample:
- sort buckets' numbers in decreasing order
- count how many values cover 90% of the sample
If the core set size is low (<=25%), data are easily compressible.
If the core set size is high (>=80%), data are not compressible.
Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update comments ]
Signed-off-by: David Sterba <dsterba@suse.com>
Calculate byte set size for data sample:
- calculate how many unique bytes have been in the sample
- for all bytes count > 0, check if we're still in the low count range
(~25%), such data are easily compressible, otherwise furhter analysis
is needed
Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update comments ]
Signed-off-by: David Sterba <dsterba@suse.com>
Walk over data sample and use memcmp to detect repeated patterns, like
zeros, but a bit more general.
Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor coding style fixes ]
Signed-off-by: David Sterba <dsterba@suse.com>
Copy sample data from the input data range to sample buffer then
calculate byte value count for that sample into bucket.
Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>
[ minor comment updates ]
Signed-off-by: David Sterba <dsterba@suse.com>
Add basic defines and structures for data sampling.
Added macros:
- For future sampling algo
- For bucket size
Heuristic workspace:
- Add bucket for storing byte type counters
- Add sample array for storing partial copy of input data range
- Add counter for store current sample size to workspace
Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor coding style fixes, comments updated ]
Signed-off-by: David Sterba <dsterba@suse.com>
Compression heuristic itself is not a compression type, as current
infrastructure provides workspaces for several compression types, it's
difficult to just add heuristic workspace.
Just refactor the code to support compression/heuristic workspaces with
maximum code sharing and minimum changes in it.
Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ coding style fixes ]
Signed-off-by: David Sterba <dsterba@suse.com>
Since we do a delalloc reserve in btrfs_truncate_block we can deadlock
with freeze. If somebody else is trying to allocate metadata for this
inode and it gets stuck in start_delalloc_inodes because of freeze we
will deadlock. Be safe and move this outside of a trans handle. This
also has a side-effect of making sure that we're not leaving stale data
behind in the other_encoding or encryption case. Not an issue now since
nobody uses it, but it would be a problem in the future.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We're holding the sb_start_intwrite lock at this point, and doing async
filemap_flush of the inodes will result in a deadlock if we freeze the
fs during this operation. This is because we could do a
btrfs_join_transaction() in the thread we are waiting on which would
block at sb_start_intwrite, and thus deadlock. Using
writeback_inodes_sb() side steps the problem by not introducing all of
these extra locking dependencies.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
If we get a significant amount of delayed refs for a single block (think
modifying multiple snapshots) we can end up spending an ungodly amount
of time looping through all of the entries trying to see if they can be
merged. This is because we only add them to a list, so we have O(2n)
for every ref head. This doesn't make any sense as we likely have refs
for different roots, and so they cannot be merged. Tracking in a tree
will allow us to break as soon as we hit an entry that doesn't match,
making our worst case O(n).
With this we can also merge entries more easily. Before we had to hope
that matching refs were on the ends of our list, but with the tree we
can search down to exact matches and merge them at insert time.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Instead of open-coding the delayed ref comparisons, add a helper to do
the comparisons generically and use that everywhere. We compare
sequence numbers last for following patches.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Make it more consistent, we want the inserted ref to be compared against
what's already in there. This will make the order go from lowest seq ->
highest seq, which will make us more likely to make forward progress if
there's a seqlock currently held.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The way we handle delalloc metadata reservations has gotten
progressively more complicated over the years. There is so much cruft
and weirdness around keeping the reserved count and outstanding counters
consistent and handling the error cases that it's impossible to
understand.
Fix this by making the delalloc block rsv per-inode. This way we can
calculate the actual size of the outstanding metadata reservations every
time we make a change, and then reserve the delta based on that amount.
This greatly simplifies the code everywhere, and makes the error
handling in btrfs_delalloc_reserve_metadata far less terrifying.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is handy for tracing problems with modifying the outstanding
extents counters.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Right now we do a lot of weird hoops around outstanding_extents in order
to keep the extent count consistent. This is because we logically
transfer the outstanding_extent count from the initial reservation
through the set_delalloc_bits. This makes it pretty difficult to get a
handle on how and when we need to mess with outstanding_extents.
Fix this by revamping the rules of how we deal with outstanding_extents.
Now instead everybody that is holding on to a delalloc extent is
required to increase the outstanding extents count for itself. This
means we'll have something like this
btrfs_delalloc_reserve_metadata - outstanding_extents = 1
btrfs_set_extent_delalloc - outstanding_extents = 2
btrfs_release_delalloc_extents - outstanding_extents = 1
for an initial file write. Now take the append write where we extend an
existing delalloc range but still under the maximum extent size
btrfs_delalloc_reserve_metadata - outstanding_extents = 2
btrfs_set_extent_delalloc
btrfs_set_bit_hook - outstanding_extents = 3
btrfs_merge_extent_hook - outstanding_extents = 2
btrfs_delalloc_release_extents - outstanding_extnets = 1
In order to make the ordered extent transition we of course must now
make ordered extents carry their own outstanding_extent reservation, so
for cow_file_range we end up with
btrfs_add_ordered_extent - outstanding_extents = 2
clear_extent_bit - outstanding_extents = 1
btrfs_remove_ordered_extent - outstanding_extents = 0
This makes all manipulations of outstanding_extents much more explicit.
Every successful call to btrfs_delalloc_reserve_metadata _must_ now be
combined with btrfs_release_delalloc_extents, even in the error case, as
that is the only function that actually modifies the
outstanding_extents counter.
The drawback to this is now we are much more likely to have transient
cases where outstanding_extents is much larger than it actually should
be. This could happen before as we manipulated the delalloc bits, but
now it happens basically at every write. This may put more pressure on
the ENOSPC flushing code, but I think making this code simpler is worth
the cost. I have another change coming to mitigate this side-effect
somewhat.
I also added trace points for the counter manipulation. These were used
by a bpf script I wrote to help track down leak issues.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Build-server workloads have hundreds of references per file after dedup.
Multiply by a few snapshots and we quickly exhaust the limit of 2730
references per extent that can fit into a 64K buffer.
Raise the limit to 16M to be consistent with other btrfs ioctls
(e.g. TREE_SEARCH_V2, FILE_EXTENT_SAME).
To minimize surprising userspace behavior, apply this change only to
the LOGICAL_INO_V2 ioctl.
Signed-off-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
Reviewed-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Tested-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that check_extent_in_eb()'s extent offset filter can be turned off,
we need a way to do it from userspace.
Add a 'flags' field to the btrfs_logical_ino_args structure to disable
extent offset filtering, taking the place of one of the existing
reserved[] fields.
Previous versions of LOGICAL_INO neglected to check whether any of the
reserved fields have non-zero values. Assigning meaning to those fields
now may change the behavior of existing programs that left these fields
uninitialized. The lack of a zero check also means that new programs
have no way to know whether the kernel is honoring the flags field.
To avoid these problems, define a new ioctl LOGICAL_INO_V2. We can
use the same argument layout as LOGICAL_INO, but shorten the reserved[]
array by one element and turn it into the 'flags' field. The V2 ioctl
explicitly checks that reserved fields and unsupported flag bits are zero
so that userspace can negotiate future feature bits as they are defined.
Since the memory layouts of the two ioctls' arguments are compatible,
there is no need for a separate function for logical_to_ino_v2 (contrast
with tree_search_v2 vs tree_search where the layout and code are quite
different). A version parameter and an 'if' statement will suffice.
Now that we have a flags field in logical_ino_args, add a flag
BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET to get the behavior we want,
and pass it down the stack to iterate_inodes_from_logical.
Motivation and background, copied from the patchset cover letter:
Suppose we have a file with one extent:
root@tester:~# zcat /usr/share/doc/cpio/changelog.gz > /test/a
root@tester:~# sync
Split the extent by overwriting it in the middle:
root@tester:~# cat /dev/urandom | dd bs=4k seek=2 skip=2 count=1 conv=notrunc of=/test/a
We should now have 3 extent refs to 2 extents, with one block unreachable.
The extent tree looks like:
root@tester:~# btrfs-debug-tree /dev/vdc -t 2
[...]
item 9 key (1103101952 EXTENT_ITEM 73728) itemoff 15942 itemsize 53
extent refs 2 gen 29 flags DATA
extent data backref root 5 objectid 261 offset 0 count 2
[...]
item 11 key (1103175680 EXTENT_ITEM 4096) itemoff 15865 itemsize 53
extent refs 1 gen 30 flags DATA
extent data backref root 5 objectid 261 offset 8192 count 1
[...]
and the ref tree looks like:
root@tester:~# btrfs-debug-tree /dev/vdc -t 5
[...]
item 6 key (261 EXTENT_DATA 0) itemoff 15825 itemsize 53
extent data disk byte 1103101952 nr 73728
extent data offset 0 nr 8192 ram 73728
extent compression(none)
item 7 key (261 EXTENT_DATA 8192) itemoff 15772 itemsize 53
extent data disk byte 1103175680 nr 4096
extent data offset 0 nr 4096 ram 4096
extent compression(none)
item 8 key (261 EXTENT_DATA 12288) itemoff 15719 itemsize 53
extent data disk byte 1103101952 nr 73728
extent data offset 12288 nr 61440 ram 73728
extent compression(none)
[...]
There are two references to the same extent with different, non-overlapping
byte offsets:
[------------------72K extent at 1103101952----------------------]
[--8K----------------|--4K unreachable----|--60K-----------------]
^ ^
| |
[--8K ref offset 0--][--4K ref offset 0--][--60K ref offset 12K--]
|
v
[-----4K extent-----] at 1103175680
We want to find all of the references to extent bytenr 1103101952.
Without the patch (and without running btrfs-debug-tree), we have to
do it with 18 LOGICAL_INO calls:
root@tester:~# btrfs ins log 1103101952 -P /test/
Using LOGICAL_INO
inode 261 offset 0 root 5
root@tester:~# for x in $(seq 0 17); do btrfs ins log $((1103101952 + x * 4096)) -P /test/; done 2>&1 | grep inode
inode 261 offset 0 root 5
inode 261 offset 4096 root 5 <- same extent ref as offset 0
(offset 8192 returns empty set, not reachable)
inode 261 offset 12288 root 5
inode 261 offset 16384 root 5 \
inode 261 offset 20480 root 5 |
inode 261 offset 24576 root 5 |
inode 261 offset 28672 root 5 |
inode 261 offset 32768 root 5 |
inode 261 offset 36864 root 5 \
inode 261 offset 40960 root 5 > all the same extent ref as offset 12288.
inode 261 offset 45056 root 5 / More processing required in userspace
inode 261 offset 49152 root 5 | to figure out these are all duplicates.
inode 261 offset 53248 root 5 |
inode 261 offset 57344 root 5 |
inode 261 offset 61440 root 5 |
inode 261 offset 65536 root 5 |
inode 261 offset 69632 root 5 /
In the worst case the extents are 128MB long, and we have to do 32768
iterations of the loop to find one 4K extent ref.
With the patch, we just use one call to map all refs to the extent at once:
root@tester:~# btrfs ins log 1103101952 -P /test/
Using LOGICAL_INO_V2
inode 261 offset 0 root 5
inode 261 offset 12288 root 5
The TREE_SEARCH ioctl allows userspace to retrieve the offset and
extent bytenr fields easily once the root, inode and offset are known.
This is sufficient information to build a complete map of the extent
and all of its references. Userspace can use this information to make
better choices to dedup or defrag.
Signed-off-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
Reviewed-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Tested-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
[ copy background and motivation from cover letter ]
Signed-off-by: David Sterba <dsterba@suse.com>
The LOGICAL_INO ioctl provides a backward mapping from extent bytenr and
offset (encoded as a single logical address) to a list of extent refs.
LOGICAL_INO complements TREE_SEARCH, which provides the forward mapping
(extent ref -> extent bytenr and offset, or logical address). These are
useful capabilities for programs that manipulate extents and extent
references from userspace (e.g. dedup and defrag utilities).
When the extents are uncompressed (and not encrypted and not other),
check_extent_in_eb performs filtering of the extent refs to remove any
extent refs which do not contain the same extent offset as the 'logical'
parameter's extent offset. This prevents LOGICAL_INO from returning
references to more than a single block.
To find the set of extent references to an uncompressed extent from [a, b),
userspace has to run a loop like this pseudocode:
for (i = a; i < b; ++i)
extent_ref_set += LOGICAL_INO(i);
At each iteration of the loop (up to 32768 iterations for a 128M extent),
data we are interested in is collected in the kernel, then deleted by
the filter in check_extent_in_eb.
When the extents are compressed (or encrypted or other), the 'logical'
parameter must be an extent bytenr (the 'a' parameter in the loop).
No filtering by extent offset is done (or possible?) so the result is
the complete set of extent refs for the entire extent. This removes
the need for the loop, since we get all the extent refs in one call.
Add an 'ignore_offset' argument to iterate_inodes_from_logical,
[...several levels of function call graph...], and check_extent_in_eb, so
that we can disable the extent offset filtering for uncompressed extents.
This flag can be set by an improved version of the LOGICAL_INO ioctl to
get either behavior as desired.
There is no functional change in this patch. The new flag is always
false.
Signed-off-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor coding style fixes ]
Signed-off-by: David Sterba <dsterba@suse.com>
This code was first introduced in 31db9f7c23 ("Btrfs: introduce
BTRFS_IOC_SEND for btrfs send/receive") and it was not functional, then
it got slightly refactored in e938c8ad54 ("Btrfs: code cleanups for
send/receive"), alas it was still dead. So let's remove it for good!
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
That was only an extra check to tackle a few bugs around this area, now
its safe to remove it. Replace it by an ASSERT.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is bikeshedding, but it seems people are drastically more likely to
understand "zlib:9" as compression level rather than an algorithm
version compared to "zlib9".
Based on feedback on the mailinglist, the ":9" will be the only accepted
syntax. The level must be a single digit. Unrecognized format will
result to the default, for forward compatibility in a similar way the
compression algorithm specifier was relaxed in commit
a7164fa4e0 ("btrfs: prepare for extensions in compression
options").
Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Reviewed-by: David Sterba <dsterba@suse.com>
[ tighten the accepted format ]
Signed-off-by: David Sterba <dsterba@suse.com>
Preliminary support for setting compression level for zlib, the
following works:
$ mount -o compess=zlib # default
$ mount -o compess=zlib0 # same
$ mount -o compess=zlib9 # level 9, slower sync, less data
$ mount -o compess=zlib1 # level 1, faster sync, more data
$ mount -o remount,compress=zlib3 # level set by remount
The compress-force works the same as compress'. The level is visible in
the same format in /proc/mounts. Level set via file property does not
work yet.
Required patch: "btrfs: prepare for extensions in compression options"
Signed-off-by: David Sterba <dsterba@suse.com>
Currently btrfs' code uses a mix of opencoded sizes and defines from sizes.h.
Let's unifiy the code base to always use the symbolic constants. No functional
changes
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Fix missing change from commit f8f84b2dfd
("btrfs: index check-integrity state hash by a dev_t").
Function btrfsic_dev_state_hashtable_lookup uses dev_t to generate hashval
when look in up a btrfsic_dev_state in hash table. So when we add a
btrfsic_dev_state into the hash table, it should also use dev_t.
Reproducer of this bug:
Use MOUNT_OPTIONS="-o check_int" when running xfstest, device can not be
mounted successfully. So xfstest can not run.
Signed-off-by: Gu JinXiang <gujx@cn.fujitsu.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When one of the device is missing, bbio_error() takes care of setting
the error status. And if its only IO that is pending in that stripe, it
fails to check the status of the other IO at %bbio_error before setting
the error %bi_status for the %orig_bio. Fix this by checking if
%bbio->error has exceeded the %bbio->max_errors.
Reproducer as below fdatasync error is seen intermittently.
mount -o degraded /dev/sdc /btrfs
dd status=none if=/dev/zero of=$(mktemp /btrfs/XXX) bs=4096 count=1 conv=fdatasync
dd: fdatasync failed for ‘/btrfs/LSe’: Input/output error
The reason for the intermittences of the problem is because
the following conditions have to be met, which depends on timing:
In btrfs_map_bio()
- the RAID1 the missing device has to be at %dev_nr = 1
In bbio_error()
. before bbio_error() is called the bio of the not-missing
device at %dev_nr = 0 must be completed so that the below
condition is true
if (atomic_dec_and_test(&bbio->stripes_pending)) {
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
A cleanup patch, use need_full_stripe() to replace the open code.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Qu Wenruo <quwenruo.btrfs@gmx.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Code cleanup for better understanding:
Variable needs_unlock to be called extent_locked to show state as
opposed to action. Changed the type to int, to reduce code in the
critical path.
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
At few places we could use BLK_STS_OK and BLK_STS_NOSUPP.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Satoru Taekeuchi <satoru.takeuchi@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ dropped first hunk btrfs_endio_direct_read ]
Signed-off-by: David Sterba <dsterba@suse.com>
These are useful for debugging problems where we mess with
trans->block_rsv to make sure we're not screwing something up.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We can get this from the ref we've passed in.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is just excessive information in the ref_head, and makes the code
complicated. It is a relic from when we had the heads and the refs in
the same tree, which is no longer the case. With this removal I've
cleaned up a bunch of the cruft around this old assumption as well.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We do a couple different cleanup operations on the ref head. We adjust
counters, we'll free any reserved space if we didn't end up using the
ref, and we clear the pending csum bytes. Move all these disparate
things into cleanup_ref_head and clean up the logic in
__btrfs_run_delayed_refs so that it handles the !ref case a lot cleaner,
as well as making run_one_delayed_ref() only deal with real refs and not
the ref head.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We only use this logic if our ref isn't a ref_head, so move it up into
the if (ref) case since we know that this is a normal ref and not a
delayed ref head.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Move this code out to a helper function to further simplivy
__btrfs_run_delayed_refs.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Move the extent_op cleanup for an empty head ref to a helper function to
help simplify __btrfs_run_delayed_refs.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Simplify the error handling in __btrfs_run_delayed_refs by breaking out
the code used to return a head back to the delayed_refs tree for
processing into a helper function.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We were only doing btrfs_check_space_for_delayed_refs() if the metadata
space was full, ie we couldn't allocate chunks. This assumes we'll be
able to allocate chunks during transaction commit, but since nothing
does a LIMIT flush during the transaction commit this won't actually
happen unless we happen to run shy of actual space. We already take
into account a full fs in btrfs_check_space_for_delayed_refs() so just
kill this extra check to make sure we're ending the transaction when we
need to.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We were having corruption issues that were tied back to problems with
the extent tree. In order to track them down I built this tool to try
and find the culprit, which was pretty successful. If you compile with
this tool on it will live verify every ref update that the fs makes and
make sure it is consistent and valid. I've run this through with
xfstests and haven't gotten any false positives. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update error messages, add fixup from Dan Carpenter to handle errors
of read_tree_block ]
Signed-off-by: David Sterba <dsterba@suse.com>
We need the actual root for the ref verifier tool to work, so change
these functions to pass the root around instead. This will be used in
a subsequent patch.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This adds the infrastructure for turning ref verify on and off for a
mount, to be used by a later patch.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ enhnance btrfs_print_mod_info to print if ref-verify is compiled in ]
Signed-off-by: David Sterba <dsterba@suse.com>
The use of sector_t in the callchain of submit_extent_page is not
necessary. Switch to u64 and rename the variable and use byte units
instead of 512b, ie. dropping the >> 9 shifts and avoiding the
con(tro)versions of sector_t.
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We're going to remove sector_t and will use 'offset', so this patch
frees the name.
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The use of sector_t is not necessry, it's just for a warning. Switch to
u64 and rename the variable and use byte units instead of 512b, ie.
dropping the >> 9 shifts. The messages are adjusted as well.
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We pass in a pointer in our send arg struct, this means the struct size
doesn't match with 32bit user space and 64bit kernel space. Fix this by
adding a compat mode and doing the appropriate conversion.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ move structure to the beginning, next to receive 32bit compat ]
Signed-off-by: David Sterba <dsterba@suse.com>
When device is missing without the -o degraded option then its an error
so report it as an error instead of a warning. And when -o degraded
option is provided, log the missing device as warning.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ switch error to bool ]
Signed-off-by: David Sterba <dsterba@suse.com>
EIO is only for the IO failure to the device, avoid it. Use ENOENT as
that's the closest error code describing what happened.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
add_missing_dev() can return device pointer so that IS_ERR/PTR_ERR can
be used to check for the actual error that occurred in the function.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
[ minor error message adjustment ]
Signed-off-by: David Sterba <dsterba@suse.com>
Remove variables 'start' and 'end', which are set but never used.
Signed-off-by: Christos Gkekas <chris.gekas@gmail.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We now get a harmless compile-time on 32-bit architectures:
fs/btrfs/tree-checker.c: In function 'check_extent_data_item':
fs/btrfs/tree-checker.c:189:70: error: format '%lu' expects argument of type 'long unsigned int', but argument 6 has type 'unsigned int' [-Werror=format=]
This changes the format string to use %zu instead of %lu for size_t.
Fixes: c1f6520bf360 ("btrfs: tree-checker: Enhance output for check_extent_data_item")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that we have the combo of flushing twice, which can make sure IO
have started since the second flush will wait for page lock which
won't be unlocked unless setting page writeback and queuing ordered
extents, we don't need %async_submit_draining, %async_delalloc_pages
and %nr_async_submits to tell whether the IO has actually started.
Moreover, all the flushers in use are followed by functions that wait
for ordered extents to complete, so %nr_async_submits, which tracks
whether bio's async submit has made progress, doesn't really make
sense.
However, %async_delalloc_pages is still required by shrink_delalloc()
as that function doesn't flush twice in the normal case (just issues a
writeback with WB_REASON_FS_FREE_SPACE).
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
By setting compression for a defrag task, the task will start IO at
the end of defrag.
After the combo of filemap_flush(), we've already made sure that
dirty pages have made progress via async compress thread because the
second filemap_flush() will wait for page lock, which won't be
unlocked until those pages have been marked as writeback and ordered
extents have been queued.
And this is for per-inode defrag, it's not helpful to wait on a global
%async_delalloc_pages and %nr_async_submits from fs_info.
Although waiting on %nr_async_submits means that all bios are
submitted down to per-device schedule IO lists, it doesn't wait for
their completions, thus users still need to do fsync/sync to make sure
the data is on disk. While with this change, it makes sure that pages
are marked with writeback bits and will be submitted asynchronously
shortly, therefore, the behavior of defrag option '-c' remains unchanged.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This was intended to congest higher layers to not send bios, but as
1) the congested bit has been taken by writeback
Async bios come from buffered writes and DIO writes.
For DIO writes, we want to submit them ASAP, while for buffered writes,
writeback uses balance_dirty_pages() to throttle how much dirty pages we
can have.
2) and no one is waiting for %nr_async_bios down to zero,
Historically, it was introduced along with changes which let
checksumming workload spread accross different cpus. And at that time,
pdflush was used instead of per-bdi flushing, perhaps pdflush did not
have the necessary information for writeback to do throttling.
We can safely remove them now.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
[ additional explanation from mails, removed unused variable 'limit' ]
Signed-off-by: David Sterba <dsterba@suse.com>