The helper is trivial and used only once, open code it. It's safe to
remove the 'if', the pointer is validated in build_backref_tree().
Signed-off-by: David Sterba <dsterba@suse.com>
The from/to CPU/disk helpers for balance args are used only in volumes,
no need to define them in accessors.h.
Signed-off-by: David Sterba <dsterba@suse.com>
We disable offloading checksum to workqueues and do it synchronously when
the checksum algorithm is fast. However, as reported in the link below,
RAID0 with multiple devices may suffer from the sync checksum, because
"fast checksum" is still not fast enough to catch up with RAID0 writing.
We don't have an effective way to determine whether to offload or not,
for now add a sysfs knob so this can be debugged. This is intentionally
under CONFIG_BTRFS_DEBUG so ti's not exposed to users as it may be
removed in the future agin.
Introduce fs_devices->offload_csum_mode, so that a btrfs developer can
change the behavior by writing to /sys/fs/btrfs/<uuid>/offload_csum. The
default is "auto" which is the same as the previous behavior. Or, you
can set "on" or "off" (or "y" or "n" whatever kstrtobool() accepts) to
always/never offload checksum.
More benchmark need to be collected with this knob to implement a proper
criteria to enable/disable checksum offloading.
Link: https://lore.kernel.org/linux-btrfs/20230731152223.4EFB.409509F4@e16-tech.com/
Link: https://lore.kernel.org/linux-btrfs/p3vo3g7pqn664mhmdhlotu5dzcna6vjtcoc2hb2lsgo2fwct7k@xzaxclba5tae/
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[BUG]
I have got at least two crash report for RAID6 syndrome generation, no
matter if it's AVX2 or SSE2, they all seems to have a similar
calltrace with corrupted RAX:
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP PTI
Workqueue: btrfs-rmw rmw_rbio_work [btrfs]
RIP: 0010:raid6_sse21_gen_syndrome+0x9e/0x130 [raid6_pq]
RAX: 0000000000000000 RBX: 0000000000001000 RCX: ffffa0ff4cfa3248
RDX: 0000000000000000 RSI: ffffa0f74cfa3238 RDI: 0000000000000000
Call Trace:
<TASK>
rmw_rbio+0x5c8/0xa80 [btrfs]
process_one_work+0x1c7/0x3d0
worker_thread+0x4d/0x380
kthread+0xf3/0x120
ret_from_fork+0x2c/0x50
</TASK>
[CAUSE]
The cause is not known. Recently I also hit this in AVX512 path, and
that's even in v5.15 backport, which doesn't have any of my RAID56
rework.
Furthermore according to the registers:
RAX: 0000000000000000 RBX: 0000000000001000 RCX: ffffa0ff4cfa3248
The RAX register is showing the number of stripes (including PQ), which
is not correct (0). But the remaining two registers are all sane.
- RBX is the sectorsize
For x86_64 it should always be 4K and matches the output.
- RCX is the pointers array
Which is from rbio->finish_pointers, and it looks like a sane
kernel address.
[WORKAROUND]
For now, I can only add extra debug ASSERT()s before we call raid6
gen_syndrome() helper and hopes to catch the problem.
The debug requires both CONFIG_BTRFS_DEBUG and CONFIG_BTRFS_ASSERT
enabled.
My current guess is some use-after-free, but every report is only having
corrupted RAX but seemingly valid pointers doesn't make much sense.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
At btrfs_free_tree_block(), we are always initializing a delayed reference
to drop the given extent buffer but we only use if it does not belong to a
log root tree. So we are doing unnecessary work here and increasing the
duration of a critical section as this is normally called while holding a
lock on the parent tree block (if any) and while holding a log transaction
open.
So initialize the delayed reference only if the extent buffer is not from
a log tree, avoiding unnecessary work and making the code also a bit
easier to follow.
Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
During an incremental send, before determining if we need to send a hole
(write operations full of zeroes) we will search for the last extent's
end offset if we are at the first slot of a leaf and the last processed
extent's end offset is smaller then the current extent's start offset.
However we are repeating this search in case we had the last extent's end
offset undefined (set to the (u64)-1 value) when we entered
maybe_send_hole(), wasting time.
So avoid this duplicated search by combining the two conditions that
trigger a search for the last extent's end offset into a single if
statement.
Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The validation of vol args v2 name in snapshot and device remove ioctls
is not done properly. A terminating NUL is written to the end of the
buffer unconditionally, assuming that this would be the last place in
case the buffer is used completely. This does not communicate back the
actual error (either an invalid or too long path).
Factor out all such cases and use a helper to do the verification,
simply look for NUL in the buffer. There's no expected practical
change, the size of buffer is 4088, this is enough for most paths or
names.
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
The validation of vol args name in several ioctls is not done properly.
a terminating NUL is written to the end of the buffer unconditionally,
assuming that this would be the last place in case the buffer is used
completely. This does not communicate back the actual error (either an
invalid or too long path).
Factor out all such cases and use a helper to do the verification,
simply look for NUL in the buffer. There's no expected practical change,
the size of buffer is 4088, this is enough for most paths or names.
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
The function btrfs_transaction_in_commit() is no longer used, its last
use was removed in commit 11aeb97b45 ("btrfs: don't arbitrarily slow
down delalloc if we're committing"), so just remove it.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The IS_ENABLED() macro already guarantees the result will be a
suitable boolean return value ("1" for enabled, and "0" for disabled).
Thus, it seems that the "!!" used right before is unnecessary to force
the 0/1 values.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Neal Gompa <neal@gompa.dev>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The purpose of the BUG_ON is not clear. The helper btrfs_grab_root()
could return a NULL in case args->root would be a NULL or if there are
zero references. Then we check if the root pointer stored in the inode
still exists.
The whole call chain is for iget:
btrfs_iget
btrfs_iget_path
btrfs_iget_locked
iget5_locked
btrfs_init_locked_inode
which is called from many contexts where we the root pointer is used and
we can safely assume has enough references.
Signed-off-by: David Sterba <dsterba@suse.com>
Checking extent item size in add_inline_refs() is redundant, we do that
already in tree-checker after reading the extent buffer and it won't
change under normal circumstances. It was added long ago in
8da6d5815c ("Btrfs: added btrfs_find_all_roots()") and does not seem
to have a clear purpose.
Similar case in extent_from_logical(), added in a542ad1baf ("btrfs:
added helper functions to iterate backrefs").
Signed-off-by: David Sterba <dsterba@suse.com>
The BUG_ON is deep in the qgroup code where we can expect that it
exists. A NULL pointer would cause a crash.
It was added long ago in 550d7a2ed5 ("btrfs: qgroup: Add new qgroup
calculation function btrfs_qgroup_account_extents()."). It maybe made
sense back then as the quota enable/disable state machine was not that
robust as it is nowadays, so we can just delete it.
Signed-off-by: David Sterba <dsterba@suse.com>
The only caller do_walk_down() of btrfs_qgroup_trace_subtree() validates
the value of level and uses it several times before it's passed as an
argument. Same for root_eb that's called 'next' in the caller.
Change both BUG_ONs to assertions as this is to assure proper interface
use rather than real errors.
Signed-off-by: David Sterba <dsterba@suse.com>
There's only one caller of tree_move_down() that does not pass level 0
so the assertion is better suited here.
Signed-off-by: David Sterba <dsterba@suse.com>
Change BUG_ON to proper error handling if building the path buffer
fails. The pointers are not printed so we don't accidentally leak kernel
addresses.
Signed-off-by: David Sterba <dsterba@suse.com>
Change BUG_ON to proper error handling when an unexpected inode number
is encountered. As the comment says this should never happen.
Signed-off-by: David Sterba <dsterba@suse.com>
Change BUG_ON to a proper error handling in the unlikely case of seeing
data when the command is started. This is supposed to be reset when the
command is finished (send_cmd, send_encoded_extent).
Signed-off-by: David Sterba <dsterba@suse.com>
The may_destroy_subvol() looks up a root by a key, allowing to do an
inexact search when key->offset is -1. It's never expected to find such
item, as it would break the allowed range of a root id.
Signed-off-by: David Sterba <dsterba@suse.com>
The find_first_extent_item() helper looks up an extent item by a key,
allowing to do an inexact search when key->offset is -1. It's never
expected to find such item, as it would break the allowed range of a
extent item offset.
Signed-off-by: David Sterba <dsterba@suse.com>
The extent_from_logical() helper looks up an extent item by a key,
allowing to do an inexact search when key->offset is -1. It's never
expected to find such item, as it would break the allowed range of a
extent item offset.
The same error is already handled in btrfs_backref_iter_start() so add a
comment for consistency.
Signed-off-by: David Sterba <dsterba@suse.com>
Same comment was added to this type of error, unify that and drop the
assertion as we'd find out quickly that something is wrong after
returning -EUCLEAN.
Signed-off-by: David Sterba <dsterba@suse.com>
The memory allocation error in add_async_extent() is not handled
properly, return an error and push the BUG_ON to the caller. Handling it
there is not trivial so at least make it visible.
Signed-off-by: David Sterba <dsterba@suse.com>
The "do_list" variable has a rather confusing name, so remove it and
directly use btrfs_is_free_space_inode() instead.
Reviewed-by: Boris Burkov <boris@bur.io>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The "do_list" variable is only used once, plus its name/meaning is a bit
confusing, so remove it and directory use btrfs_is_free_space_inode().
Reviewed-by: Boris Burkov <boris@bur.io>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When adding or removing and inode to/from the root's delalloc list,
instead of using a BUG_ON() to validate list emptiness, use ASSERT()
since this is to check logic errors rather than real errors.
Reviewed-by: Boris Burkov <boris@bur.io>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The merge and split callbacks for an inode's io tree are supposed to be
called while the io tree's spinlock is being held, so that the given
extent_state records are stable, not modified or freed while the callbacks
are using them. So add lockdep assertions in the callbacks.
Reviewed-by: Boris Burkov <boris@bur.io>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When setting and clearing a delalloc range, at btrfs_set_delalloc_extent()
and btrfs_clear_delalloc_extent(), we are adding/removing the inode
to/from the root's list of delalloc inodes while under the protection of
the inode's lock. This however is not needed, we can add and remove the
inode to the root's list without holding the inode's lock because here
we are under the protection of the io tree's lock, reducing the size of
the critical section delimited by the inode's lock. The inode's lock is
used in many other places such as when finishing an ordered extent (when
calling btrfs_update_inode_bytes() or btrfs_delalloc_release_metadata(),
or decreasing the number of outstanding extents) or when reserving space
when doing a buffered or direct IO write (calls to functions from
delalloc-space.c).
So move the inode add/remove operations to the root's list of delalloc
inodes to outside the critical section delimited by the inode's lock.
This also allows us to get rid of the BTRFS_INODE_IN_DELALLOC_LIST flag
since we can rely on the inode's delalloc bytes counter to determine if
the inode is or is not in the list.
The following fio based test, that exercises IO to multiple files in the
same subvolume, was used to test:
$ cat test.sh
#!/bin/bash
DEV=/dev/nullb0
MNT=/mnt/nullb0
MOUNT_OPTIONS="-o ssd"
mkfs.btrfs -f $DEV &> /dev/null
mount $MOUNT_OPTIONS $DEV $MNT
fio --direct=0 --ioengine=sync --thread --directory=$MNT \
--invalidate=1 --group_reporting=1 \
--new_group --rw=randwrite --size=50m --numjobs=200 \
--bs=4k --fsync_on_close=0 --fallocate=none --end_fsync=0 \
--name=foo --filename_format=FioWorkloads.\$jobnum
umount $MNT
The test was run on a non-debug kernel (Debian's default kernel config)
against a 16G null block device.
Result before this patch:
WRITE: bw=81.9MiB/s (85.9MB/s), 81.9MiB/s-81.9MiB/s (85.9MB/s-85.9MB/s), io=9.77GiB (10.5GB), run=122136-122136msec
Result after this patch:
WRITE: bw=86.8MiB/s (91.0MB/s), 86.8MiB/s-86.8MiB/s (91.0MB/s-91.0MB/s), io=9.77GiB (10.5GB), run=115180-115180msec
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The function btrfs_add_delalloc_inodes() adds a single inode its root's
list of delalloc inodes, so it doesn't make any sense at all for the
function's name to be plural. Rename it to the singular form
btrfs_add_delalloc_inode() to avoid any confusion.
Reviewed-by: Boris Burkov <boris@bur.io>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This function requires the delalloc lock of the inode's root to be held,
so assert it's held.
Reviewed-by: Boris Burkov <boris@bur.io>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There's no need to pass a root argument to __btrfs_del_delalloc_inode()
and btrfs_del_delalloc_inode(), we can just pass the inode since the root
is always the root associated to that inode. Some remove the root argument
from these functions.
Reviewed-by: Boris Burkov <boris@bur.io>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There's no need to pass a root argument to btrfs_add_delalloc_inodes(), we
can just pass the inode since the root is always the root associated to
the inode in the context it's called. So remove it and have the single
caller pass only the inode.
Reviewed-by: Boris Burkov <boris@bur.io>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Do a cleanup in the rest of the headers:
- add forward declarations for types referenced by pointers
- add includes when types need them
This fixes potential compilation problems if the headers are reordered
or the missing includes are not provided indirectly.
Signed-off-by: David Sterba <dsterba@suse.com>
Do a cleanup in more headers:
- add forward declarations for types referenced by pointers
- add includes when types need them
This fixes potential compilation problems if the headers are reordered
or the missing includes are not provided indirectly.
Signed-off-by: David Sterba <dsterba@suse.com>
Do a cleanup in the short headers:
- add forward declarations for types referenced by pointers
- add includes when types need them
This fixes potential compilation problems if the headers are reordered
or the missing includes are not provided indirectly.
Signed-off-by: David Sterba <dsterba@suse.com>
The fs_info and sectorsize remain the same during the loops, no need to
set them on each iteration.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add a convenience helper to get a fs_info from a VFS inode pointer
instead of open coding the chain or using btrfs_sb() that in some cases
does one more pointer hop. This is implemented as a macro (still with
type checking) so we don't need full definitions of struct btrfs_inode,
btrfs_root or btrfs_fs_info.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add convenience helpers to get a fs_info from a page or folio pointer
instead of open coding the chain or using btrfs_sb() that in some cases
does one more pointer hop. This is implemented as a macro (still with
type checking) so we don't need full definitions of struct page, folio,
btrfs_root and btrfs_fs_info. The latter can't be static inlines as this
would create loop between ctree.h <-> fs.h, or the headers would have to
be restructured.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Add convenience helpers to get a struct btrfs_inode from a page or folio
pointer instead of open coding the chain or intermediate BTRFS_I. This
is implemented as a macro (still with type checking) so we don't need
full definitions of struct page or address_space.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Allocate fs_info and root to have a valid fs_info pointer in case it's
dereferenced by a helper outside of tests, like find_lock_delalloc_range().
Signed-off-by: David Sterba <dsterba@suse.com>
__btrfs_add_free_space is only used in free-space-cache.c,
so mark it static.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Lijuan Li <lilijuan@iscas.ac.cn>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The recommended pattern for transaction abort after error is to place it
right after the error is handled. That way it's easier to locate where
it failed and help debugging.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The recommended pattern for transaction abort after error is to place it
right after the error is handled. That way it's easier to locate where
it failed and help debugging.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The recommended pattern for transaction abort after error is to place it
right after the error is handled. That way it's easier to locate where
it failed and help debugging.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The error values returned by btrfs_insert_empty_items() are following
the common patter of 0/-errno, but some callers check for a value > 0,
which can't happen. Document that and update calls to not expect
positive values.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The balance state machine is complex so it's good to verify the
assumptions in helpers, however reset_balance_state() is used
at the end of balance and fs_info::balance_ctl is properly set up before
and protected by the exclusive op ownership in btrfs_balance().
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The file extents are normally reserved in subvolume roots but could be
also in the data reloc tree. Change the BUG_ON to assertions as this
verifies the usage assumptions.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The BUG_ON in btrfs_set_buffer_lockdep_class() is a sanity check of the
level which is verified in callers, e.g. when initializing an extent
buffer or reading from an eb header. Change it to an assertion as this
would not happen unless things are really bad and would fail elsewhere
too.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There's one caller of btrfs_read_roots() and that already uses the
tree_root pointer, it's pointless to BUG_ON on it. As it's an assumption
of the initialization helpers make it an assert instead.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The BUG_ON verifies a condition that should be guaranteed by the correct
use of the path search (with keep_locks and lowest_level set), an
assertion is the suitable check.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
