Commit Graph

207 Commits

Author SHA1 Message Date
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
Kent Overstreet
aa76bd3321 bcachefs: Add a missing bch2_trans_relock() call
This was causing an assertion to pop in fsck, in one of the repair
paths.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:12 -04:00
Kent Overstreet
caaa66aa54 bcachefs: Better approach to write vs. read lock deadlocks
Instead of unconditionally upgrading read locks to intent locks in
do_bch2_trans_commit(), this patch changes the path that takes write
locks to first trylock, and then if trylock fails check if we have a
conflicting read lock, and restart the transaction if necessary.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:12 -04:00
Kent Overstreet
b301105b48 bcachefs: normalize_read_intent_locks
This is a new approach to avoiding the self deadlock we'd get if we
tried to take a write lock on a node while holding a read lock - we
simply upgrade the readers to intent.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:12 -04:00
Kent Overstreet
db92f2ea5e bcachefs: Optimize btree lookups in write path
This patch significantly reduces the number of btree lookups required in
the extent update path.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:12 -04:00
Kent Overstreet
cf3c68cda6 bcachefs: No need to clone iterators for update
Since btree_path is now internally refcounted, we don't need to clone an
iterator before calling bch2_trans_update() if we'll be mutating it.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:11 -04:00
Kent Overstreet
f48361b00c bcachefs: Drop some fast path tracepoints
These haven't turned out to be useful

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:11 -04:00
Kent Overstreet
67e0dd8f0d bcachefs: btree_path
This splits btree_iter into two components: btree_iter is now the
externally visible componont, and it points to a btree_path which is now
reference counted.

This means we no longer have to clone iterators up front if they might
be mutated - btree_path can be shared by multiple iterators, and cloned
if an iterator would mutate a shared btree_path. This will help us use
iterators more efficiently, as well as slimming down the main long lived
state in btree_trans, and significantly cleans up the logic for iterator
lifetimes.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:11 -04:00
Kent Overstreet
fbf14104da bcachefs: Improve an error message
When we detect an invalid key being inserted, we should print what code
was doing the update.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:11 -04:00
Kent Overstreet
f21566f17a bcachefs: Kill BTREE_ITER_NODES
We really only need to distinguish between btree iterators and btree key
cache iterators - this is more prep work for btree_path.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:11 -04:00
Kent Overstreet
6fba6b83b4 bcachefs: Prefer using btree_insert_entry to btree_iter
This moves some data dependencies forward, to improve pipelining.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:11 -04:00
Kent Overstreet
a0a568794d bcachefs: More renaming
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:11 -04:00
Kent Overstreet
f7a966a3e2 bcachefs: Clean up/rename bch2_trans_node_* fns
These utility functions are for managing btree node state within a
btree_trans - rename them for consistency, and drop some unneeded
arguments.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:11 -04:00
Kent Overstreet
78cf784eaa bcachefs: Further reduce iter->trans usage
This is prep work for splitting btree_path out from btree_iter -
btree_path will not have a pointer to btree_trans.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:11 -04:00
Kent Overstreet
05046a962f bcachefs: Better algorithm for btree node merging in write path
The existing algorithm was O(n^2) in the number of updates in the
commit.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:11 -04:00
Kent Overstreet
5f8077cca8 bcachefs: Kill BTREE_ITER_SET_POS_AFTER_COMMIT
BTREE_ITER_SET_POS_AFTER_COMMIT is used internally to automagically
advance extent btree iterators on sucessful commit.

But with the upcomnig btree_path patch it's getting more awkward to
support, and it adds overhead to core data structures that's only used
in a few places, and can be easily done by the caller instead.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:11 -04:00
Kent Overstreet
638c6ff951 bcachefs: Refactor bch2_trans_update_extent()
This consolidates the code for doing extent updates, and makes the btree
iterator usage a bit cleaner and more efficient.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:11 -04:00
Kent Overstreet
9f6bd30703 bcachefs: Reduce iter->trans usage
Disfavoured, and should go away.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:10 -04:00
Kent Overstreet
84841b0d13 bcachefs: bch2_dump_trans_iters_updates()
This factors out bch2_dump_trans_iters_updates() from the iter alloc
overflow path, and makes some small improvements to what it prints.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:10 -04:00
Kent Overstreet
dc02bed6d9 bcachefs: Free iterator if we have duplicate
This helps - but does not fully fix - the outstanding "transaction
iterator overflow" bugs.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:10 -04:00
Kent Overstreet
e363726602 bcachefs: Ensure that new inodes hit underlying btree
Inode creation is done with non-cached btree iterators, but then in the
same transaction the inode may be updated again with a cached iterator -
it makes cache coherency easier if new inodes always land in the
underlying btree.

This patch adds a check to bch2_trans_update() - if the same key is
updated multiple times in the same transaction with both cached and non
cache iterators, use the non cached iterator.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:10 -04:00
Kent Overstreet
9cba7bf7c7 bcachefs: Don't drop read locks at transaction commit time
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:10 -04:00
Kent Overstreet
1a488e7306 bcachefs: Kill BTREE_INSERT_NOUNLOCK
With the recent transaction restart changes, it's no longer needed - all
transaction commits have BTREE_INSERT_NOUNLOCK semantics.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:10 -04:00
Kent Overstreet
b253a90d06 bcachefs: Btree splits no longer automatically cause a transaction restart
With the new and improved handling of transaction restarts, this should
finally be safe.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:10 -04:00
Kent Overstreet
955af63441 bcachefs: __bch2_trans_commit() no longer calls bch2_trans_reset()
It's now the caller's responsibility to call bch2_trans_begin.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:09 -04:00
Kent Overstreet
e5af273fce bcachefs: trans->restarted
Start tracking when btree transactions have been restarted - and assert
that we're always calling bch2_trans_begin() immediately after
transaction restart.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:09 -04:00
Kent Overstreet
6918bb55f6 bcachefs: Don't traverse iterators in __bch2_trans_commit()
They should already be traversed, and we're asserting that since the
introduction of iter->should_be_locked

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:09 -04:00
Kent Overstreet
ed5580b43b bcachefs: Fix a btree iterator leak
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:09 -04:00
Kent Overstreet
9f1833cadd bcachefs: Update btree ptrs after every write
This closes a significant hole (and last known hole) in our ability to
verify metadata. Previously, since btree nodes are log structured, we
couldn't detect lost btree writes that weren't the first write to a
given node. Additionally, this seems to have lead to some significant
metadata corruption on multi device filesystems with metadata
replication: since a write may have made it to one device and not
another, if we read that btree node back from the replica that did have
that write and started appending after that point, the other replica
would have a gap in the bset entries and reading from that replica
wouldn't find the rest of the bsets.

But, since updates to interior btree nodes are now journalled, we can
close this hole by updating pointers to btree nodes after every write
with the currently written number of sectors, without negatively
affecting performance. This means we will always detect lost or corrupt
metadata - it also means that our btree is now a curious hybrid of COW
and non COW btrees, with all the benefits of both (excluding
complexity).

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:08 -04:00
Kent Overstreet
e3a67bdb6e bcachefs: Regularize argument passing of btree_trans
btree_trans should always be passed when we have one - iter->trans is
disfavoured. This mainly updates old code in btree_update_interior.c,
some of which predates btree_trans.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:08 -04:00
Kent Overstreet
b00fde8fb1 bcachefs: BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE
Add a new flag to control assertions about updating to internal snapshot
nodes, that normally should not be written to - to be used in an
upcoming patch.

Also do some renaming - trigger_flags is now update_flags.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:08 -04:00
Kent Overstreet
297d89343d bcachefs: Extensive triggers cleanups
- We no longer mark subsets of extents, they're marked like regular
   keys now - which means we can drop the offset & sectors arguments
   to trigger functions
 - Drop other arguments that are no longer needed anymore in various
   places - fs_usage
 - Drop the logic for handling extents in bch2_mark_update() that isn't
   needed anymore, to match bch2_trans_mark_update()
 - Better logic for hanlding the BTREE_ITER_CACHED_NOFILL case, where we
   don't have an old key to mark

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:07 -04:00
Kent Overstreet
8c3f6da9fc bcachefs: Improve iter->should_be_locked
Adding iter->should_be_locked introduced a regression where it ended up
not being set on the iterator passed to bch2_btree_update_start(), which
is definitely not what we want.

This patch requires it to be set when calling bch2_trans_update(), and
adds various fixups to make that happen.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:06 -04:00
Kent Overstreet
b89726ab86 bcachefs: Kill __btree_delete_at()
With trans->updates2 gone, we can now drop this helper and use
bch2_btree_delete_at() instead.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:06 -04:00
Kent Overstreet
a49e9a0589 bcachefs: Fix null ptr deref when splitting compressed extents
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:06 -04:00
Kent Overstreet
5db95e50e1 bcachefs: Re-implement extent merging in transaction commit path
We haven't had extent merging in quite some time. It used to be done by
the btree code when sorting btree nodes, but that was eliminated as part
of the work to separate extent handling from core btree code.

This patch re-implements extent merging in the transaction commit path.
We don't currently have the ability to merge reflink pointers, we need
to do some work on the triggers code to be able to do that without
ending up with incorrect refcounts.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:06 -04:00
Kent Overstreet
81d22e5d83 bcachefs: Refactor extent_handle_overwrites()
Prep work for extent merging

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:06 -04:00
Kent Overstreet
cd8319fdd9 bcachefs: Kill trans->updates2
Now that extent handling has been lifted to bch2_trans_update(), we
don't need to keep two different lists of updates.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:06 -04:00
Kent Overstreet
8e6bbc4181 bcachefs: Move extent_handle_overwrites() to bch2_trans_update()
This lifts handling of overlapping extents out of __bch2_trans_commit()
and moves it to where we first do the update - which means that
BTREE_ITER_WITH_UPDATES can now work correctly in extents mode.

Also, this patch reworks how extent triggers work: previously, on
partial extent overwrite we would pass this information to the trigger,
telling it what part of the extent was being overwritten. But, this
approach has had too many subtle corner cases - now, we only mark whole
extents, meaning on partial extent overwrite we unmark the old extent
and mark the new extent.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:06 -04:00
Kent Overstreet
5288e66a7b bcachefs: BTREE_ITER_WITH_UPDATES
This drops bch2_btree_iter_peek_with_updates() and replaces it with a
new flag, BTREE_ITER_WITH_UPDATES, and also reworks
bch2_btree_iter_peek_slot() to respect it too.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:05 -04:00
Kent Overstreet
531a0095c9 bcachefs: Improve btree iterator tracepoints
This patch adds some new tracepoints to the btree iterator code, and
adds new fields to the existing tracepoints - primarily for the iterator
position.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:05 -04:00
Kent Overstreet
bc3f8b25f3 bcachefs: Check for errors from bch2_trans_update()
Upcoming refactoring is going to change bch2_trans_update() to start
returning transaction restarts.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:05 -04:00
Kent Overstreet
a6336910b1 bcachefs: Fix for buffered writes getting -ENOSPC
Buffered writes may have to increase their disk reservation at btree
update time, due to compression and erasure coding being unpredictable:
O_DIRECT writes should be checking for -ENOSPC, but buffered writes have
already been accepted and should not.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:04 -04:00
Kent Overstreet
d6462f494d bcachefs: Split extents if necessary in bch2_trans_update()
Currently, we handle multiple overlapping extents in the same
transaction commit by doing fixups in bch2_trans_update() - this patch
extents that to split updates when necessary. The next patch that
changes the reflink code to not fragment extents when making them
indirect will require this.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:03 -04:00
Kent Overstreet
bbfcb4519d bcachefs: Fix bch2_extent_can_insert() call
It was being skipped when hole punching, leading to problems when
splitting compressed extents.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:03 -04:00
Kent Overstreet
4f6dad46cb bcachefs: Add a tracepoint for when we block on journal reclaim
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:02 -04:00
Kent Overstreet
bc2e5d5c66 bcachefs: Fix an out of bounds read
bch2_varint_decode() can read up to 7 bytes past the end of the buffer,
which means we need to allocate slightly larger key cache buffers.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:02 -04:00
Kent Overstreet
8ce600d447 bcachefs: Fix for btree_gc repairing interior btree ptrs
Using the normal transaction commit path to insert and journal updates
to interior nodes hadn't been done before this repair code was written,
not surprising that there was a bug.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:01 -04:00
Kent Overstreet
fa272f33bb bcachefs: Always check for invalid bkeys in trans commit path
We check for this prior to metadata being written, but we're seeing some
strange bugs lately, and this will help catch those closer to where they
occur.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:01 -04:00
Kent Overstreet
0ef107859b bcachefs: Fix journal_reclaim_wait_done()
Can't run arbitrary code inside a wait_event() conditional, due to
task state being weird...

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:00 -04:00