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>

This patch changes journal_entry_open() to initialize the new journal
entry, not __journal_entry_close().

This also means that journal_cur_seq() refers to the sequence number of
the last journal entry when we don't have an open journal entry, not the
next one.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

When we do an interior btree update, we create new btree nodes and link
them into the btree in memory, but they don't become reachable on disk
until later, when btree_update_nodes_written_trans() runs.

Updates to the new nodes can thus happen before they're reachable on
disk, and if the updates to those new nodes are written before the nodes
become reachable, we would then drop the journal pin for those updates
before the btree has them.

This is what the journal pin in bch2_btree_update_start() was protecting
against. However, it's not actually needed because we don't allow
subsequent append writes to btree nodes until the node is reachable on
disk.

Dropping this unneeded pin also fixes a bug introduced by "bcachefs:
Journal seq now incremented at entry open, not close" - in the new code,
if the journal is completely empty a journal pin list for
journal_cur_seq() won't exist.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

This change is prep work for moving some work from
__journal_entry_close() to journal_entry_open(): without this change,
journal_entry_open() doesn't know if it's going to be able to open a new
journal entry until the cmpxchg loop, meaning it can't create the new
journal pin entry and update other global state because those have to be
done prior to the cmpxchg opening the new journal entry.

Fortunately, we don't call bch2_journal_halt() from interrupt context.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

This replaces the journal flag JOURNAL_NEED_WRITE with per-journal buf
state - more explicit, and solving a race in the old code that would
lead to entries being opened and written unnecessarily.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

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

This fixes a regression from "bcachefs: Stash a copy of key being
overwritten in btree_insert_entry". In btree_key_can_insert_cached(), we
may reallocate the key cache key, invalidating pointers previously
returned by peek() - fix it by issuing a transaction restart.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

This fixes a regression from "bcachefs: Heap allocate printbufs" -
bch2_sb_field_validate() was leaking an error string.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

Checking btree_node_may_write() isn't atomic with the other btree flags,
dirty and need_write in particular. There was a rare race where we'd
unblock a node from writing while __btree_node_flush() was setting
need_write, and no thread would notice that the node was now both able
to write and needed to be written.

Fix this by adding btree node flags for will_make_reachable and
write_blocked that can be checked in the cmpxchg loop in
__bch2_btree_node_write.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

bch2_btree_node_write_cond() was only used in one place - this inlines
it into __btree_node_flush() and makes the cmpxchg loop actually
correct.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

btree_node_write_if_need() kicks off a btree node write only if
need_write is set; this makes the locking easier to reason about by
moving the check into the cmpxchg loop in __bch2_btree_node_write().
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

There was a rare recursive locking bug, in __bch2_btree_node_write()
nowrite path -> btree_node_write_done(), in the path that kicks off
another write.

This splits out an inner __btree_node_write_done() that expects to be
run with the btree node lock held.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

In sysfs, files can only output at most PAGE_SIZE. This is a problem for
debug info that needs to list an arbitrary number of times, and because
of this limit some of our debug info has been terser and harder to read
than we'd like.

This patch moves info about journal pins and cached btree nodes to
debugfs, and greatly expands and improves the output we return.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

This cacheline aligns struct journal, and puts j->reservations and
j->prereserved on their own cacheline - we may want to split them up in
a separate patch.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

This is for adding an array of strings for btree node flag names.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

This was just dead code.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

If we're not able to flush anything, we shouldn't keep looping.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

In btree_update_interior.c, we were changing a path's level directly -
which affects path sort order - without re-sorting paths, leading to
assertions when bch2_path_get() verified paths were sorted correctly.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

journal_flush_done() was overwriting did_work, thus occasionally
returning false when it did do work and occasional assertions in the
shutdown sequence because we didn't completely flush the key cache.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

This patch changes printbufs dynamically allocate and reallocate a
buffer as needed. Stack usage has become a bit of a problem, and a major
cause of that has been static size string buffers on the stack.

The most involved part of this refactoring is that printbufs must now be
exited with printbuf_exit().
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Fewer random on-stack char arrays.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

We're hitting a strange bug with transaction paths not being sorted
correctly - this dumps transaction paths in the order we thought was
sorted, which will hopefully shed some light as to what's going on.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

When key cache pins were put onto their own list, we neglected to update
bch2_journal_pins_to_text() to print them.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

bch2_trans_begin() invalidates all iterators, until they're revalidated
by calling peek() or traverse().
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

Triggers can generate additional btree updates - we need to run alloc
triggers after all other triggers have run, because they generate
updates for the alloc btree.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

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

Upcoming patches are doing more work on the triggers code, this patch
just moves code around.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

We're now coming up with triggers that modify the update being done. A
bkey_s_c is const - bkey_i is the correct type to be using here.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

vstruct_bytes() was returning a u64 - it should be a size_t, the corect
type for the size of anything that fits in memory.

Also replace a 64 bit divide with div_u64().
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

On btree node read error, it's helpful to see what we were trying to
read - was it all zeroes?
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>