Commit 0c0cbfdb dropped the ctx->pos
update before the call to dir_emit. This breaks the userspace
implementation, causing the directory reads to be stuck in an infinite
loop. This doesn't happen in the kernel because the vfs handles the
updates to ctx->pos, but in the fuse implementation nobody updates
it.
Signed-off-by: Ariel Miculas <ariel.miculas@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

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

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

We now read the line from the buffer atomically, which means we have to
allow the buffer to grow past STDIO_REDIRECT_BUFSIZE if we're waiting
for a full line - this behaviour is necessary for
stdio_redirect_readline_timeout() in the next patch.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

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

fsck_err() now optionally takes a btree_trans; if the current thread has
one, it is required that it be passed.

The next patch will use this to unlock when waiting for user input.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Make things more consistent and ensure that we're using u64 bitfields -
key types and btree ids are already around 32 bits.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

the order in which btree_gc walks keys have changed, so we no longer
have the sort of issues with online fsck this assertion was warning
about.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Needed for online fsck; we need the trigger to initialize newly
allocated buckets and generation number changes while gc is running.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Next change will move gc_alloc_start initialization into the alloc
trigger, so we have to mark those first.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Blocking the journal was needed to finish checking old style accounting,
but that code is gone and it's not needed in the alloc rewrite,
mark_lock is sufficient for synchronization.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

- improve error paths
- call bch2_fs_start() separately, after applying late-parsed options
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Fold into bch2_fs_get_tree()
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

The btree write buffer takes as input keys from the journal, sorts them,
deduplicates them, and flushes them back to the btree in sorted order.

The disk space accounting rewrite is moving accounting to normal btree
keys, with update (in this case deltas) accumulated in the write buffer
and then flushed to the btree; but this is going to increase the number
of keys handled by the write buffer by perhaps as much as a factor of
3x-5x.

The overhead from copying around and sorting this many keys would cause
a significant performance regression, but: there is huge locality in
updates to accounting keys that we can take advantage of.

Instead of appending accounting keys to the list of keys to be sorted,
this patch adds an eytzinger search tree of recently seen accounting
keys. We look up the accounting key in the eytzinger search tree and
apply the delta directly, adding it if it doesn't exist, and
periodically prune the eytzinger tree of unused entries.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

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

Add counters for how much disk space we're using per btree.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

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

Helper to show raw accounting in sysfs, mainly for debugging.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Helper to show raw accounting in sysfs, mainly for debugging.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

We no longer have to walk the whole btree to calculate compression
stats.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

This adds per-compression-type accounting of compressed and uncompressed
size as well as number of extents - meaning we can now see compression
ratio (without walking the whole filesystem).
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Verify that the in-memory accounting verifies the on-disk accounting
after a clean shutdown.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

bch2_replicas_gc2() is used for garbage collection superblock replicas
entries that are empty - this converts it to the new accounting scheme.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Rewrite fsck/gc for the new accounting scheme.

This adds a second set of in-memory accounting counters for gc to use;
like with other parts of gc we run all trigger in TRIGGER_GC mode, then
compare what we calculated to existing in-memory accounting at the end.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

More dead code deletion
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

More dead code deletion.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Dead code.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

More deletion of dead code.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

More ripping out of the old disk space accounting.

Note that the new disk space accounting is incompatible with the old,
and writing out old style disk space accounting with the new code is
infeasible.

This means upgrading and downgrading past this version requires
regenerating accounting.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

With bch2_ioctl_fs_usage(), this is now dead code.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

This converts bch2_ioctl_fs_usage() to read from the new disk
accounting, via bch2_fs_replicas_usage_read().
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Deleting code for the old disk accounting scheme.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Reading disk accounting now requires an eytzinger lookup (see:
bch2_accounting_mem_read()), but the per-device counters are used
frequently enough that we'd like to still be able to read them with just
a percpu sum, as in the old code.

This patch special cases the device counters; when we update in-memory
accounting we also update the old style percpu counters if it's a deice
counter update.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

This fixes a performance regression in journal replay; without
colaescing accounting keys we have multiple keys at the same position,
which means journal_keys_peek_upto() has to skip past many overwritten
keys - turning journal replay into an O(n^2) algorithm.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Main part of the disk accounting rewrite.

This is a wholesale rewrite of the existing disk space accounting, which
relies on percepu counters that are sharded by journal buffer, and
rolled up and added to each journal write.

With the new scheme, every set of counters is a distinct key in the
accounting btree; this fixes scaling limitations of the old scheme,
where counters took up space in each journal entry and required multiple
percpu counters.

Now, in memory accounting requires a single set of percpu counters - not
multiple for each in flight journal buffer - and in the future we'll
probably also have counters that don't use in memory percpu counters,
they're not strictly required.

An accounting update is now a normal btree update, using the btree write
buffer path. At transaction commit time, we apply accounting updates to
the in memory counters, which are percpu counters indexed in an
eytzinger tree by the accounting key.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Teach the btree write buffer how to accumulate accounting keys - instead
of having the newer key overwrite the older key as we do with other
updates, we need to add them together.

Also, add a flag so that write buffer flush knows when journal replay is
finished flushing accounting, and teach it to hold accounting keys until
that flag is set.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Until accounting keys hit the btree, they are deltas, not new versions
of the existing key; this means we have to teach journal replay to
accumulate them.

Additionally, the journal doesn't track precisely which entries have
been flushed to the btree; it only tracks a range of entries that may
possibly still need to be flushed.

That means we need to compare accounting keys against the version in the
btree and only flush updates that are newer.

There's another wrinkle with the write buffer: if the write buffer
starts flushing accounting keys before journal replay has finished
flushing accounting keys, journal replay will see the version number
from the new updates and updates from the journal will be lost.

To avoid this, journal replay has to flush accounting keys first, and
we'll be adding a flag so that write buffer flush knows to hold
accounting keys until then.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

New key type for the disk space accounting rewrite.

 - Holds a variable sized array of u64s (may be more than one for
   accounting e.g. compressed and uncompressed size, or buckets and
   sectors for a given data type)

 - Updates are deltas, not new versions of the key: this means updates
   to accounting can happen via the btree write buffer, which we'll be
   teaching to accumulate deltas.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

This updates bcachefs to use the new mount API:

- Update the file_system_type to use the new init_fs_context()
  function.

- Define the new fs_context_operations functions.

- No longer register bch2_mount() and bch2_remount(); these are now
  called via the new fs_context functions.

- Define a new helper type, bch2_opts_parse that includes a struct
  bch_opts and additionally a printbuf used to save options that can't
  be parsed until after the FS is opened. This enables us to parse as
  many options as possible prior to opening the filesystem while saving
  those options that need the open FS for later parsing.
Signed-off-by: Thomas Bertschinger <tahbertschinger@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

This introduces a new error code, option_needs_open_fs, which is used to
indicate that an attempt was made to parse a mount option prior to
opening a filesystem, when that mount option requires an open filesystem
in order to be validated.

Returning this error results in bch2_parse_one_mount_opt() saving that
option for later parsing, after the filesystem is opened.
Signed-off-by: Thomas Bertschinger <tahbertschinger@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>