When flushing the btree write buffer, we pull write buffer keys directly
from the journal instead of letting the journal write path copy them to
the write buffer.
When flushing from the currently open journal buffer, we have to block
new reservations and wait for outstanding reservations to complete.
Recheck the reservation state after blocking new reservations:
previously, we were checking the reservation count from before calling
__journal_block().
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Prep work for journal rewind, where the seq we're replaying from may be
different than the last journal entry's last_seq.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
The new guard(), scoped_guard() allow for more natural code.
Some of the uses with creative flow control have been left.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Different versions differ on the size of the blacklist range; it is
theoretically possible that we could end up with blacklisted journal
sequence numbers newer than the newest seq we find in the journal, and
pick a new start seq that's blacklisted.
Explicitly check for this in bch2_fs_journal_start().
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Convert device IO refs to enumerated_refs, for easier debugging of
refcount issues.
Simple conversion: enumerate all users and convert to the new helpers.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
bch2_print_string_as_lines() is a low level helper that allows messages
longer than 1k to be printed without truncation.
But we should always be printing with the helpers that take a filesystem
object, if we're in fsck they direct output to the userspace process
controlling fsck instead of the dmesg log.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
_init_early() is for initialization that cannot fail, and often must
happen for teardown partway through initialization to work.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Don't set JOURNAL_running until we're also calling
journal_space_available() for the first time.
If JOURNAL_running is set, shutdown will write an empty journal entry -
but this will hit an assert in journal_entry_open() if we've never
called journal_space_available().
Reported-by: syzbot+53bb24d476ef8368a7f0@syzkaller.appspotmail.com
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
If we crash when the journal pin fifo is completely full - i.e. we're
at the maximum number of dirty journal entries - that may put us in a
sticky situation in recovery, as journal replay will need to be able to
open new journal entries in order to get going.
bch2_fs_journal_start() already had provisions for resizing the journal
pin fifo if needed, but it needs a fudge factor to ensure there's room
for journal replay.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
We now have separate per device io_refs for read and write access.
This fixes a device removal bug where the discard workers were still
running while we're removing alloc info for that device.
It's also a bit of hardening; we no longer allow writes to devices that
are read-only.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Convert these to standard error codes, which means we can pass them
outside the journal code, they're easier to pass to tracepoints, etc.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Since we're increasing the number of 'struct journal_bufs', we don't
want them all permanently holding onto buffers for the journal data -
that'd be 16 * 2MB = 32MB, or potentially more.
Add a single-element mempool (open coded, since buffer size varies),
this also means we won't be hitting the memory allocator every time we
open and close a journal entry/buffer.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Previously, we fixed journal resize spuriousl failing with
-BCH_ERR_open_buckets_empty, but initial journal allocation was missed
because it didn't invoke the "block on allocator" loop at all.
Factor out the "loop on allocator" code to fix that.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
The discard path is supposed to issue journal flushes when there's too
many buckets empty buckets that need a journal commit before they can be
written to again, but at some point this code seems to have been lost.
Bring it back with a new optimization to make sure we don't issue too
many journal flushes: the journal now tracks the sequence number of the
most recent flush in progress, which the discard path uses when deciding
which buckets need a journal flush.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
In the previous commit b3d82c2f27, code was added to prevent journal sequence
overflow. Among them, the code added to journal_entry_open() uses the
bch2_fs_fatal_err_on() function to handle errors.
However, __journal_res_get() , which calls journal_entry_open() , calls
journal_entry_open() while holding journal->lock , but bch2_fs_fatal_err_on()
internally tries to acquire journal->lock , which results in a deadlock.
So we need to add a locked helper to handle fatal errors even when the
journal->lock is held.
Fixes: b3d82c2f27 ("bcachefs: Guard against journal seq overflow")
Signed-off-by: Jeongjun Park <aha310510@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Running the preempt tiering tests with a lower than normal journal
reclaim delay turned up a shutdown hang - a lost wakeup, caused because
flushing a journal pin (e.g. key cache/write buffer) can generate a new
journal pin.
The "simple" fix of adding the correct wakeup didn't work because of
ordering issues; if we flush btree node pins too aggressively before
other pins have completed, we end up spinning where each flush iteration
generates new work.
So to fix this correctly:
- The list of flushed journal pins is now broken out by type, so that
we can wait for key cache/write buffer pin flushing to complete
before flushing dirty btree nodes
- A new closure_waitlist is added for bch2_journal_flush_pins; this one
is only used under or when we're taking the journal lock, so it's
pretty cheap to add rigorously correct wakeups to journal_pin_set()
and journal_pin_drop().
Additionally, bch2_journal_seq_pins_to_text() is moved to
journal_reclaim.c, where it belongs, along with a bit of other small
renaming and refactoring.
Besides fixing the hang, the better ordering between key cache/write
buffer flushing and btree node flushing should help or fix the "unmount
taking excessively long" a few users have been noticing.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
If a block device (e.g. your typical consumer SSD) is taking multiple
seconds for IOs (typically flushes), we don't want to emit the "journal
stuck" message prematurely.
Also, make sure to drop the btree_trans srcu lock if we're blocking for
more than a second.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Harder to screw up if we're explicit about the range, and more correct
as journal reservations can be outstanding on multiple journal entries
simultaneously.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Wraparound is impractical to handle since in various places we use 0 as
a sentinal value - but 64 bits (or 56, because the btree write buffer
steals a few bits) is enough for all practical purposes.
Reported-by: syzbot+73ed43fbe826227bd4e0@syzkaller.appspotmail.com
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
The early-early allocation path, bch2_bucket_alloc_new_fs(), is no
longer needed - and inconsistencies around new_fs_bucket_idx have been a
frequent source of bugs.
Reported-by: syzbot+592425844580a6598410@syzkaller.appspotmail.com
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Instead of throwing standard error codes, we should be throwing
dedicated private error codes, this greatly improves debugability.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This part of addressing
https://github.com/koverstreet/bcachefs/issues/656
where we're getting stuck in bch2_journal_meta() in the dump tool.
We shouldn't be invoking the journal without a ref on c->writes (if
we're not RW), and there's no reason for the dump tool to be going
read-write.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Fix a bug where mount was failing with -ERESTARTSYS:
https://github.com/koverstreet/bcachefs/issues/741
We only want the interruptible wait when called from fsync.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Like how we already do when the allocator seems to be stuck, check if
we're waiting too long for a journal reservation and print some debug
info.
This is specifically to track down
https://github.com/koverstreet/bcachefs/issues/656
which is showing up in userspace where we don't have sysfs/debugfs to
get the journal debug info.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Use try_cmpxchg() family of functions instead of
cmpxchg (*ptr, old, new) == old. x86 CMPXCHG instruction returns
success in ZF flag, so this change saves a compare after cmpxchg
(and related move instruction in front of cmpxchg).
Also, try_cmpxchg() implicitly assigns old *ptr value to "old" when
cmpxchg fails. There is no need to re-read the value in the loop.
No functional change intended.
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Brian Foster <bfoster@redhat.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
On a new filesystem or device we have to allocate the journal with a
bump allocator, because allocation info isn't ready yet - but when
hot-adding a device that doesn't have a journal, we don't want to use
that path.
Reported-by: syzbot+24a867cb90d8315cccff@syzkaller.appspotmail.com
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
