Commit Graph

36 Commits

Author SHA1 Message Date
Kent Overstreet
84f1638795 bcachefs: bch_sb_field_downgrade
Add a new superblock section that contains a list of
  { minor version, recovery passes, errors_to_fix }

that is - a list of recovery passes that must be run when downgrading
past a given version, and a list of errors to silently fix.

The upcoming disk accounting rewrite is not going to be fully
compatible: we're going to have to regenerate accounting both when
upgrading to the new version, and also from downgrading from the new
version, since the new method of doing disk space accounting is a
completely different architecture based on deltas, and synchronizing
them for every jounal entry write to maintain compatibility is going to
be too expensive and impractical.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-01 11:47:07 -05:00
Kent Overstreet
73ab9e0386 bcachefs: Factor out darray resize slowpath
Move the slowpath (actually growing the darray) to an out-of-line
function; also, add some helpers for the upcoming btree write buffer
rewrite.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-01 11:46:52 -05:00
Kent Overstreet
f5d26fa31e bcachefs: bch_sb_field_errors
Add a new superblock section to keep counts of errors seen since
filesystem creation: we'll be addingcounters for every distinct fsck
error.

The new superblock section has entries of the for [ id, count,
time_of_last_error ]; this is intended to let us see what errors are
occuring - and getting fixed - via show-super output.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-11-01 21:11:08 -04:00
Kent Overstreet
aaad530ac6 bcachefs: BTREE_ID_logged_ops
Add a new btree for long running logged operations - i.e. for logging
operations that we can't do within a single btree transaction, so that
they can be resumed if we crash.

Keys in the logged operations btree will represent operations in
progress, with the state of the operation stored in the value.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:10:12 -04:00
Kent Overstreet
1809b8cba7 bcachefs: Break up io.c
More reorganization, this splits up io.c into
 - io_read.c
 - io_misc.c - fallocate, fpunch, truncate
 - io_write.c

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:10:12 -04:00
Kent Overstreet
a9a7bbab14 bcachefs: bch2_acl_to_text()
We can now print out acls from bch2_xattr_to_text(), when the xattr
contains an acl.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:10:12 -04:00
Kent Overstreet
8e877caaad bcachefs: Split out snapshot.c
subvolume.c has gotten a bit large, this splits out a separate file just
for managing snapshot trees - BTREE_ID_snapshots.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:10:11 -04:00
Kent Overstreet
401585fe87 bcachefs: btree_journal_iter.c
Split out a new file from recovery.c for managing the list of keys we
read from the journal: before journal replay finishes the btree iterator
code needs to be able to iterate over and return keys from the journal
as well, so there's a fair bit of code here.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:10:10 -04:00
Kent Overstreet
a37ad1a3ab bcachefs: sb-clean.c
Pull code for bch_sb_field_clean out into its own file.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:10:10 -04:00
Kent Overstreet
fb8e5b4cae bcachefs: sb-members.c
Split out a new file for bch_sb_field_members - we'll likely want to
move more code here in the future.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:10:10 -04:00
Kent Overstreet
8079aab085 bcachefs: Split up btree_update_leaf.c
We now have
  btree_trans_commit.c
  btree_update.c

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:10:10 -04:00
Kent Overstreet
dbbfca9f41 bcachefs: Split up fs-io.[ch]
fs-io.c is too big - time for some reorganization
 - fs-dio.c: direct io
 - fs-pagecache.c: pagecache data structures (bch_folio), utility code

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:10:10 -04:00
Kent Overstreet
a8b3a677e7 bcachefs: Nocow support
This adds support for nocow mode, where we do writes in-place when
possible. Patch components:

 - New boolean filesystem and inode option, nocow: note that when nocow
   is enabled, data checksumming and compression are implicitly disabled

 - To prevent in-place writes from racing with data moves
   (data_update.c) or bucket reuse (i.e. a bucket being reused and
   re-allocated while a nocow write is in flight, we have a new locking
   mechanism.

   Buckets can be locked for either data update or data move, using a
   fixed size hash table of two_state_shared locks. We don't have any
   chaining, meaning updates and moves to different buckets that hash to
   the same lock will wait unnecessarily - we'll want to watch for this
   becoming an issue.

 - The allocator path also needs to check for in-place writes in flight
   to a given bucket before giving it out: thus we add another counter
   to bucket_alloc_state so we can track this.

 - Fsync now may need to issue cache flushes to block devices instead of
   flushing the journal. We add a device bitmask to bch_inode_info,
   ei_devs_need_flush, which tracks devices that need to have flushes
   issued - note that this will lead to unnecessary flushes when other
   codepaths have already issued flushes, we may want to replace this with
   a sequence number.

 - New nocow write path: look up extents, and if they're writable write
   to them - otherwise fall back to the normal COW write path.

XXX: switch to sequence numbers instead of bitmask for devs needing
journal flush

XXX: ei_quota_lock being a mutex means bch2_nocow_write_done() needs to
run in process context - see if we can improve this

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:51 -04:00
Kent Overstreet
a8c752bb1d bcachefs: New on disk format: Backpointers
This patch adds backpointers: we now have a reverse index from device
and offset on that device (specifically, offset within a bucket) back to
btree nodes and (non cached) data extents.

The first 40 backpointers within a bucket are stored in the alloc key;
after that backpointers spill over to the next backpointers btree. This
is to help avoid performance regressions from additional btree updates
on large streaming workloads.

This patch adds all the code for creating, checking and repairing
backpointers. The next patch in the series is going to use backpointers
for copygc - finally getting rid of the need to scan all extents to do
copygc.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:50 -04:00
Kent Overstreet
920e69bc3d bcachefs: Btree write buffer
This adds a new method of doing btree updates - a straight write buffer,
implemented as a flat fixed size array.

This is only useful when we don't need to read from the btree in order
to do the update, and when reading is infrequent - perfect for the LRU
btree.

This will make LRU btree updates fast enough that we'll be able to use
it for persistently indexing buckets by fragmentation, which will be a
massive boost to copygc performance.

Changes:
 - A new btree_insert_type enum, for btree_insert_entries. Specifies
   btree, btree key cache, or btree write buffer.

 - bch2_trans_update_buffered(): updates via the btree write buffer
   don't need a btree path, so we need a new update path.

 - Transaction commit path changes:
   The update to the btree write buffer both mutates global, and can
   fail if there isn't currently room. Therefore we do all write buffer
   updates in the transaction all at once, and also if it fails we have
   to revert filesystem usage counter changes.

   If there isn't room we flush the write buffer in the transaction
   commit error path and retry.

 - A new persistent option, for specifying the number of entries in the
   write buffer.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:50 -04:00
Kent Overstreet
a7ecd30c83 bcachefs: Factor out two_state_shared_lock
We have a unique lock used for controlling adding to the pagecache: the
lock has two states, where both states are shared - the lock may be held
multiple times for either state - but not both states at the same time.

This is exactly what we need for nocow mode locking, so this patch pulls
it out of fs.c into its own file.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:45 -04:00
Daniel Hill
92095781e0 bcachefs: Mean and variance
This module provides a fast 64bit implementation of basic statistics
functions, including mean, variance and standard deviation in both
weighted and unweighted variants, the unweighted variant has a 32bit
limitation per sample to prevent overflow when squaring.

Signed-off-by: Daniel Hill <daniel@gluo.nz>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:43 -04:00
Kent Overstreet
cd5afabea1 bcachefs: btree_locking.c
Start to centralize some of the locking code in a new file; more locking
code will be moving here in the future.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:39 -04:00
Kent Overstreet
615f867c14 bcachefs: Improved errcodes
Instead of overloading standard error codes (EINTR/EAGAIN), and defining
short lists of error codes in multiple places that potentially end up
overlapping & conflicting, we're now going to have one master list of
error codes.

Error codes are defined with an x-macro: thus we also have
bch2_err_str() now.

Also, error codes have a class field. Now, instead of checking for
errors with ==, code should use bch2_err_matches(), which returns true
if the error is equal to or a sub-error of the error class.

This means we can define unique errors for every source location where
an error is generated, which will help improve our error messages.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:36 -04:00
Kent Overstreet
c501fef6de bcachefs: Pull out data_update.c
This is the start of reorganizing the data IO paths. The plan is to also
break apart io.c into data_read.c and data_write.c, and migrate_write
will be renamed to the data_update path.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:34 -04:00
Kent Overstreet
401ec4db63 bcachefs: Printbuf rework
This converts bcachefs to the modern printbuf interface/implementation,
synced with the version to be submitted upstream.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:33 -04:00
Daniel Hill
104c69745f bcachefs: Add persistent counters
This adds a new superblock field for persisting counters
and adds a sysfs interface in counters/ exposing these counters.

The superblock field is ignored by older versions letting us avoid
an on disk version bump.

Each sysfs file outputs a counter that tracks since filesystem
creation and a counter for the current mount session.

Signed-off-by: Daniel Hill <daniel@gluo.nz>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:32 -04:00
Kent Overstreet
d326ab2f5d bcachefs: LRU btree
This implements new persistent LRUs, to be used for buckets containing
cached data, as well as stripes ordered by time when a block became
empty.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:29 -04:00
Kent Overstreet
25be2e5d4a bcachefs: bch_sb_field_journal_v2
Add a new superblock field which represents journal buckets as ranges:
also move code for the superblock journal fields to journal_sb.c.

This also reworks the code for resizing the journal to write the new
superblock before using the new journal buckets, and thus be a bit
safer.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:29 -04:00
Kent Overstreet
21aec962df bcachefs: New data structure for buckets waiting on journal commit
Implement a hash table, using cuckoo hashing, for empty buckets that are
waiting on a journal commit before they can be reused.

This replaces the journal_seq field of bucket_mark, and is part of
eventually getting rid of the in memory bucket array.

We may need to make bch2_bucket_needs_journal_commit() lockless, pending
profiling and testing.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:22 -04:00
Kent Overstreet
14b393ee76 bcachefs: Subvolumes, snapshots
This patch adds subvolume.c - support for the subvolumes and snapshots
btrees and related data types and on disk data structures. The next
patches will start hooking up this new code to existing code.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:12 -04:00
Dan Robertson
59e2480ff7 bcachefs: do not compile acl mod on minimal config
Do not compile the acl.o target if BCACHEFS_POSIX_ACL is not enabled.

Signed-off-by: Dan Robertson <dan@dlrobertson.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:05 -04:00
Kent Overstreet
a3e7226268 bcachefs: New varints
Previous varint implementation used by the inode code was not nearly as
fast as it could have been; partly because it was attempting to encode
integers up to 96 bits (for timestamps) but this meant that encoding and
decoding the length required a table lookup.

Instead, we'll just encode timestamps greater than 64 bits as two
separate varints; this will make decoding/encoding of inodes
significantly faster overall.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:46 -04:00
Kent Overstreet
2ca88e5ad9 bcachefs: Btree key cache
This introduces a new kind of btree iterator, cached iterators, which
point to keys cached in a hash table. The cache also acts as a write
cache - in the update path, we journal the update but defer updating the
btree until the cached entry is flushed by journal reclaim.

Cache coherency is for now up to the users to handle, which isn't ideal
but should be good enough for now.

These new iterators will be used for updating inodes and alloc info (the
alloc and stripes btrees).

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:41 -04:00
Kent Overstreet
08c07fea7b bcachefs: Split out extent_update.c
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:32 -04:00
Kent Overstreet
9638574229 bcachefs: Factor out fs-common.c
This refactoring makes the code easier to understand by separating the
bcachefs btree transactional code from the linux VFS code - but more
importantly, it's also to share code with the fuse port.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:28 -04:00
Kent Overstreet
76426098e4 bcachefs: Reflink
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:25 -04:00
Kent Overstreet
5b8a9227f8 bcachefs: Split out bkey_sort.c
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:12 -04:00
Kent Overstreet
cd575ddf57 bcachefs: Erasure coding
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:11 -04:00
Kent Overstreet
7b3f84ea7d bcachefs: Split out alloc_background.c
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:10 -04:00
Kent Overstreet
1c6fdbd8f2 bcachefs: Initial commit
Initially forked from drivers/md/bcache, bcachefs is a new copy-on-write
filesystem with every feature you could possibly want.

Website: https://bcachefs.org

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:07 -04:00