Something funny is going on with the new code for restoring the journal
write point, and it's hard to reproduce.

We do want to debug this because resuming writing to the journal in the
wrong spot could be something serious. For now, replace the assertion
with an error message and revert to old behaviour when it happens.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

We're seeing a very strange bug where journal_flush_delay sometimes gets
set to 0 in the superblock. Together with the preceding patch, this
should help us track it down.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

This moves validation of superblock options to bch2_sb_validate(), so
they'll be checked in the write path as well.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

Now we've got strings for metadata versions - this changes
bch2_sb_to_text() and our mount log message to use it.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

Previously, we'd go into an infinite loop when attempting to cache a
bkey in the key cache larger than 128 u64s - since we were only using a
u8 for the size field, it'd get rounded up to 256 then truncated to 0.
Oops.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

These warnings are symptomatic of something else going wrong, we don't
want them spamming up the logs as that'll make it harder to find the
real issue.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

This patch tweaks the journal recovery path so that we start writing
right after where we left off, instead of the next empty bucket. This is
partly prep work for supporting zoned devices, but it's also good to do
in general to avoid the journal completely filling up and getting stuck.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

Inspired by CCAN darray - simple, stupid resizable (dynamic) arrays.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

BTREE_TRIGGER_WANTS_OLD_AND_NEW didn't work correctly when the old and
new key were both alloc keys, but different versions - it required old
and new key type to be identical, and this bug is a problem for the new
allocator rewrite.

This patch fixes it by checking if the old and new key have the same
trigger functions - the different versions of alloc (and inode) keys
have the same trigger functions.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

This replaces the switch statements in bch2_mark_key(),
bch2_trans_mark_key() with new bkey methods - prep work for the next
patch, which fixes BTREE_TRIGGER_WANTS_OLD_AND_NEW.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

We recently started stashing a copy of the key being overwritten in
btree_insert_entry: this is helpful for avoiding multiple calls to
bch2_btree_path_peek_slot() and bch2_journal_keys_peek() in the
transaction commit path.

But it turns out this has a problem - when we run mem/atomic triggers,
we've done a couple things that can invalidate the pointer to the old
key's value. This makes the optimization of stashing a pointer to the
old value questionable, but for now this patch revalidates that pointer
before running mem triggers.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

This turns bch2_dump_trans_updates() into a to_text() method - this way
it can be used by debug tracing.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Add a new error macro that also dumps transaction updates in addition to
doing an emergency shutdown - when a transaction update discovers or is
causing a fs inconsistency, it's helpful to see what updates it was
doing.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

As we've already reserved space in the journal this optimization doesn't
actually buy us anything, and when doing list_journal debugging it
deletes information we want.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

In BTREE_ITER_FILTER_SNAPHOTS mode, we skip over keys in unrelated
snapshots. When we hit the end of an inode, if the next inode(s) are in
a different subvolume, we could potentially have to skip past many keys
before finding a key we can return to the caller, so they can terminate
the iteration.

This adds a peek_upto() variant to solve this problem, to be used when
we know the range we're searching within.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

This fixes a rare bug with bch2_btree_flush_all_writes() getting stuck.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

This tweaks __bch2_set_nr_journal_buckets() so that we aren't reversing
their order in the jorunal anymore - nice for rotating disks.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

This adds bch2_journal_log_msg(), which just logs a message to the
journal, and uses it to mark startup and when journal replay finishes.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

It wasn't used as iter_flags (excepting the unit tests, which this patch
fixes), and the next patch is going to need to pass in
BTREE_TRIGGER_NORUN.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

traverse_all() traverses btree paths in sorted order, so it should never
see transaction restarts due to lock ordering violations. But some code
in __bch2_btree_path_upgrade(), while necessary when not running under
traverse_all(), was causing some confusing lock ordering violations -
disabling this code under traverse_all() will let us put in some more
assertions.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

In btree_path_traverse_all() we were failing to check for -EIO in the
retry loop, and after btree node read error we'd go into an infinite
loop.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

When the iov_iter is a bvec iter, it's possible the IO was submitted
from a kthread that didn't have an mm to switch to.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

This fixes a bug in the DIO read path where, when using a loopback
device in DIO mode, we'd allocate a biovec that would get overwritten
and leaked in bio_iov_iter_get_pages() -> bio_iov_bvec_set().
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

"bcachefs: Log & error message improvements" accidentally changed the
format specifier we use for converting UUIDs to strings, which broke
mounting of encrypted filesystems - this patch reverts that change.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

Less system noise.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

This isn't a correctness issue, it just eliminates errors in the dmesg
log when we're RO.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

pr_tab_rjust() was broken and leaving a null somewhere in the output
string - this patch fixes it and simplifies it a bit.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

When bch2_trans_begin() is called and there hasn't been a transaction
restart, we presume that we're now doing something new - iterating over
different keys, and we now shouldn't keep aruond paths related to the
previous transaction, excepting the subvolumes btree.

This should fix some of our "transaction path overflow" bugs.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

This fixes a shutdown race where we were rearming journal->write_work
after the journal has already shut down.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

Options no longer have to be manually added to bch2_sb_to_text() - it
now uses the master list of options in opts.h. Also, improve some of the
formatting by converting it to tabstops.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

We were accidentally using default mount options and overwriting the
discard flag.
Signed-off-by: Daniel Hill <daniel@gluo.nz>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Six locks have a percpu mode, which we use for interior btree nodes, as
well as btree key cache keys for the subvolumes btree. We've been
switching locks back and forth between percpu and non percpu mode as
needed, but it turns out this is racy - when we're reusing an existing
node, other threads could be attempting to lock it while we're switching
it between modes.

This patch fixes this by never switching 'struct btree' between the two
modes, and instead segragating them between two different freed lists.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

This is prep work for the next patch, which is going to fix our usage of
the percpu mode of six locks by never switching struct btree between the
two modes - which means we need separate freed lists.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

We don't need to pass the number of nodes required to
bch2_btree_update_start, just whether we're doing a split at @level.
This is prep work for a fix to our usage of six lock's percpu mode,
which is going to require us to count up and allocate interior nodes and
leaf nodes seperately.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Previously, when bch2_btree_cache_scan() attempted to reclaim a node but
failed (because trylock failed, because it was dirty, etc.), it would
count that against the number of nodes it was scanning and attempting to
free. This patch changes that behaviour, so that now we only count nodes
that we then don't free if they have the accessed bit (which we also
clear).
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

After emergency shutdown, all journal entries will be written as noflush
entries, meaning they will never be used - but they'll still exist for
debugging tools to examine.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

Previous patch just moved responsibility for incrementing the journal
sequence number and initializing the new journal entry from
__journal_entry_close() to journal_entry_open(); this patch makes the
analagous change for journal reservation state, incrementing the index
into array of journal_bufs at open time.

This means that __journal_entry_close() never fails to close an open
journal entry, which is important for the next patch that will change
our emergency shutdown behaviour.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

It makes the code more readable if we work off of sequence numbers,
instead of direct indexes into the array of journal buffers.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>