If the reader acquires the read lock and then the writer enters the slow
path, while the reader proceeds to the unlock path, the following scenario
can occur without the change:
writer: pcpu_read_count(lock) return 1 (so __do_six_trylock will return 0)
reader: this_cpu_dec(*lock->readers)
reader: smp_mb()
reader: state = atomic_read(&lock->state) (there is no waiting flag set)
writer: six_set_bitmask()
then the writer will sleep forever.
Signed-off-by: Alan Huang <mmpgouride@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Add a filesystem flag to indicate whether we did a clean recovery -
using c->sb.clean after we've got rw is incorrect, since c->sb is
updated whenever we write the superblock.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
We had a bug where disk accounting keys didn't always have their version
field set in journal replay; change the BUG_ON() to a WARN(), and
exclude this case since it's now checked for elsewhere (in the bkey
validate function).
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This was added to avoid double-counting accounting keys in journal
replay. But applied incorrectly (easily done since it applies to the
transaction commit, not a particular update), it leads to skipping
in-mem accounting for real accounting updates, and failure to give them
a version number - which leads to journal replay becoming very confused
the next time around.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Previously, check_inode() would delete unlinked inodes if they weren't
on the deleted list - this code dating from before there was a deleted
list.
But, if we crash during a logged op (truncate or finsert/fcollapse) of
an unlinked file, logged op resume will get confused if the inode has
already been deleted - instead, just add it to the deleted list if it
needs to be there; delete_dead_inodes runs after logged op resume.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
BCH_SB_ERRS() has a field for the actual enum val so that we can reorder
to reorganize, but the way BCH_SB_ERR_MAX was defined didn't allow for
this.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
__bch2_fsck_err() warns if the current task has a btree_trans object and
it wasn't passed in, because if it has to prompt for user input it has
to be able to unlock it.
But plumbing the btree_trans through bkey_validate(), as well as
transaction restarts, is problematic - so instead make bkey fsck errors
FSCK_AUTOFIX, which doesn't need to warn.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
In order to check for accounting keys with version=0, we need to run
validation after they've been assigned version numbers.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
accounting read was checking if accounting replicas entries were marked
in the superblock prior to applying accounting from the journal,
which meant that a recently removed device could spuriously trigger a
"not marked in superblocked" error (when journal entries zero out the
offending counter).
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Minor refactoring - replace multiple bool arguments with an enum; prep
work for fixing a bug in accounting read.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Dealing with outside state within a btree transaction is always tricky.
check_extents() and check_dirents() have to accumulate counters for
i_sectors and i_nlink (for subdirectories). There were two bugs:
- transaction commit may return a restart; therefore we have to commit
before accumulating to those counters
- get_inode_all_snapshots() may return a transaction restart, before
updating w->last_pos; then, on the restart,
check_i_sectors()/check_subdir_count() would see inodes that were not
for w->last_pos
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Returning a positive integer instead of an error code causes error paths
to become very confused.
Closes: syzbot+c0360e8367d6d8d04a66@syzkaller.appspotmail.com
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
The pointer clean points the memory allocated by kmemdup, when the
return value of bch2_sb_clean_validate_late is not zero. The memory
pointed by clean is leaked. So we should free it in this case.
Fixes: a37ad1a3ab ("bcachefs: sb-clean.c")
Signed-off-by: Hongbo Li <lihongbo22@huawei.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
In downgrade_table_extra, the return value is needed. When it
return failed, we should exit immediately.
Fixes: 7773df19c3 ("bcachefs: metadata version bucket_stripe_sectors")
Signed-off-by: Hongbo Li <lihongbo22@huawei.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
check_topology doesn't need the srcu lock and doesn't use normal btree
transactions - we can just drop the srcu lock.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
fsck_err() jumps to the fsck_err label when bailing out; need to make
sure bp_iter was initialized...
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This fixes a kasan splat in propagate_key_to_snapshot_leaves() -
varint_decode_fast() does reads (that it never uses) up to 7 bytes past
the end of the integer.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Most or all errors will be autofix in the future, we're currently just
doing the ones that we know are well tested.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
As we iterate we need to mark that we no longer need iterators -
otherwise we'll infinite loop via the "too many iters" check when
there's many snapshots.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
if it doesn't get set we'll never be able to flush the btree write
buffer; this only happens in fake rw mode, but prevents us from shutting
down.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Syzbot reports a problem that a warning is triggered due to suspicious
use of rcu_dereference_check(). That is triggered by a call of
bch2_snapshot_tree_oldest_subvol().
The cause of the warning is that inside
bch2_snapshot_tree_oldest_subvol(), snapshot_t() is called which calls
rcu_dereference() that requires a read lock to be held. Also, the call
of bch2_snapshot_tree_next() eventually calls snapshot_t().
To fix this, call rcu_read_lock() before calling snapshot_t(). Then,
release the lock after the termination of the while loop.
Reported-by: <syzbot+f7c41a878676b72c16a6@syzkaller.appspotmail.com>
Signed-off-by: Ahmed Ehab <bottaawesome633@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
The header files bbpos.h is included twice in backpointers.c,
so one inclusion of each can be removed.
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=10783
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This factors out ec_strie_head_devs_update(), which initializes the
bitmap of devices we're allocating from, and runs it every time
c->rw_devs_change_count changes.
We also cancel pending, not allocated stripes, since they may refer to
devices that are no longer available.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Add a counter that's incremented whenever rw devices change; this will
be used for erasure coding so that it can keep ec_stripe_head in sync
and not deadlock on a new stripe when a device it wants goes away.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
We can now correctly force-remove a device that has stripes on it; this
uses the new BCH_SB_MEMBER_INVALID sentinal value.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
When reshaping existing stripes, we should keep them on the same target
that they were allocated on; to do this, we need to add a field to the
btree stripe type.
This is a tad awkward, because we only have 8 bits left, and targets are
16 bits - but we only need to store a label, not a full target.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
In backpointers fsck, we do a seqential scan of one btree, and check
references to another: extents <-> backpointers
Checking references generates random lookups, so we want to pin that
btree in memory (or only a range, if it doesn't fit in ram).
Previously, this was done with a simple check in the shrinker - "if
btree node is in range being pinned, don't free it" - but this generated
OOMs, as our shrinker wasn't well behaved if there was less memory
available than expected.
Instead, we now have two different shrinkers and lru lists; the second
shrinker being for pinned nodes, with seeks set much higher than normal
- so they can still be freed if necessary, but we'll prefer not to.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
32 bits won't overflow any time soon, but size_t is the correct type for
counting objects in memory.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
