Commit Graph

81 Commits

Author SHA1 Message Date
Kent Overstreet
6404dcc9c2 bcachefs: More enum strings
This patch converts more enums in the on disk format to our standard
x-macro-with-strings deal - to enable better pretty-printing.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:17 -04:00
Kent Overstreet
3e52c22255 bcachefs: Add journal_seq to inode & alloc keys
Add fields to inode & alloc keys that record the journal sequence number
when they were most recently modified.

For alloc keys, this is needed to know what journal sequence number we
have to flush before the bucket can be reused. Currently this is tracked
in memory, but we'll be getting rid of the in memory bucket array.

For inodes, this is needed for fsync when the inode has been evicted
from the vfs cache. Currently we use a bloom filter per outstanding
journal buf - but that mechanism has been broken since we added the
ability to not issue a flush/fua for every journal write.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:16 -04:00
Kent Overstreet
2027875bd8 bcachefs: Add BCH_SUBVOLUME_UNLINKED
Snapshot deletion needs to become a multi step process, where we unlink,
then tear down the page cache, then delete the subvolume - the deleting
flag is equivalent to an inode with i_nlink = 0.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:15 -04:00
Kent Overstreet
4db650277d bcachefs: Subvol dirents are now only visible in parent subvol
This changes the on disk format for dirents that point to subvols so
that they also record the subvolid of the parent subvol, so that we can
filter them out in other subvolumes.

This also updates the dirent code to do that filtering, and in
particular tweaks the rename code - we need to ensure that there's only
ever one dirent (counting multiplicities in different snapshots) that
point to a subvolume.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:14 -04:00
Kent Overstreet
e5fa91d7ac bcachefs: Fix restart handling in for_each_btree_key()
Code that uses for_each_btree_key often wants transaction restarts to be
handled locally and not returned. Originally, we wouldn't return
transaction restarts if there was a single iterator in the transaction -
the reasoning being if there weren't other iterators being invalidated,
and the current iterator was being advanced/retraversed, there weren't
any locks or iterators we were required to preserve.

But with the btree_path conversion that approach doesn't work anymore -
even when we're using for_each_btree_key() with a single iterator there
will still be two paths in the transaction, since we now always preserve
the path at the pos the iterator was initialized at - the reason being
that on restart we often restart from the same place.

And it turns out there's now a lot of for_each_btree_key() uses that _do
not_ want transaction restarts handled locally, and should be returning
them.

This patch splits out for_each_btree_key_norestart() and
for_each_btree_key_continue_norestart(), and converts existing users as
appropriate. for_each_btree_key(), for_each_btree_key_continue(), and
for_each_btree_node() now handle transaction restarts themselves by
calling bch2_trans_begin() when necessary - and the old hack to not
return transaction restarts when there's a single path in the
transaction has been deleted.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:14 -04:00
Kent Overstreet
6d76aefea1 bcachefs: Fix for leaking of reflinked extents
When a reflink pointer points to only part of an indirect extent, and
then that indirect extent is fragmented (e.g. by copygc), if the reflink
pointer only points to one of the fragments we leak a reference.

Fix this by storing front/back pad values in reflink pointers - when
inserting reflink pointesr, we initialize them to cover the full range
of the indirect extents we reference.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:14 -04:00
Kent Overstreet
bfe88863cf bcachefs: New on disk format to fix reflink_p pointers
We had a bug where reflink_p pointers weren't being initialized to 0,
and when we started using the second word, things broke badly.

This patch revs the on disk format version and adds cleanup code to zero
out the second word of reflink_p pointers before we start using it.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:14 -04:00
Kent Overstreet
0476fa948e bcachefs: Rev the on disk format version for snapshots
This will cause the compat code to be run that creates entries in the
subvolumes and snapshots btrees.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:13 -04:00
Kent Overstreet
7a7d17b2f7 bcachefs: Whiteouts for snapshots
This patch adds KEY_TYPE_whiteout, a new type of whiteout for snapshots,
when we're deleting and the key being deleted is in an ancestor
snapshot - and updates the transaction update/commit path to use it.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:12 -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
Kent Overstreet
e719fc34f0 bcachefs: BSET_OFFSET()
Add a field to struct bset for the sector offset within the btree node
where it was written.

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
996fb577fd bcachefs: Add an option for whether inodes use the key cache
We probably don't ever want to flip this off in production, but it may
be useful for certain kinds of testing.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:08 -04:00
Kent Overstreet
618b1c0e20 bcachefs: Split out SPOS_MAX
Internal btree code really wants a POS_MAX with all fields ~0; external
code more likely wants the snapshot field to be 0, because when we're
passing it to bch2_trans_get_iter() it's used for the snapshot we're
operating in, which should be 0 for most btrees that don't use
snapshots.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:07 -04:00
jpsollie
41e633826a bcachefs: add bcachefs xxhash support
xxhash is a much faster algorithm compared to crc32.
could be used to speed up checksum calculation.
xxhash 64-bit only, as it is much faster on 64-bit CPUs compared to xxh32.

Signed-off-by: jpsollie <janpieter.sollie@edpnet.be>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:07 -04:00
Kent Overstreet
b282a74fae bcachefs: Add an option to control sharding new inode numbers
We're seeing a bug where inode creates end up spinning in
bch2_inode_create - disabling sharding will simplify what we're testing.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:04 -04:00
Kent Overstreet
aae15aafcd bcachefs: New and improved topology repair code
This splits out btree topology repair into a separate pass, and makes
some improvements:
 - When we have to pick which of two overlapping nodes to drop keys
   from, we use the btree node header sequence number to preserve the
   newer node

 - the gc code has been changed so that it doesn't bail out if we're
   continuing/ignoring on fsck error - this way the dump tool can skip
   running the repair pass but still walk all reachable metadata

 - add a new superblock flag indicating when a filesystem is known to
   have btree topology issues, and the topology repair pass should be
   run

 - changing the start/end of a node might mean keys in that node have to
   be deleted: this patch handles that better by splitting it out into a
   separate function and running it explicitly in the topology repair
   code, previously those keys were only being dropped when the btree
   node was read in.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:02 -04:00
Kent Overstreet
ab2a29ccff bcachefs: Inode backpointers
This patch adds two new inode fields, bi_dir and bi_dir_offset, that
point back to the inode's dirent.

Since we're only adding fields for a single backpointer, files that have
been hardlinked won't necessarily have valid backpointers: we also add a
new inode flag, BCH_INODE_BACKPTR_UNTRUSTED, that's set if an inode has
ever had multiple links to it. That's ok, because we only really need
this functionality for directories, which can never have multiple
hardlinks - when we add subvolumes, we'll need a way to enemurate and
print subvolumes, and this will let us reconstruct a path to a subvolume
root given a subvolume root inode.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:58 -04:00
Kent Overstreet
e751c01a8e bcachefs: Start using bpos.snapshot field
This patch starts treating the bpos.snapshot field like part of the key
in the btree code:

* bpos_successor() and bpos_predecessor() now include the snapshot field
* Keys in btrees that will be using snapshots (extents, inodes, dirents
  and xattrs) now always have their snapshot field set to U32_MAX

The btree iterator code gets a new flag, BTREE_ITER_ALL_SNAPSHOTS, that
determines whether we're iterating over keys in all snapshots or not -
internally, this controlls whether bkey_(successor|predecessor)
increment/decrement the snapshot field, or only the higher bits of the
key.

We add a new member to struct btree_iter, iter->snapshot: when
BTREE_ITER_ALL_SNAPSHOTS is not set, iter->pos.snapshot should always
equal iter->snapshot, which will be 0 for btrees that don't use
snapshots, and alsways U32_MAX for btrees that will use snapshots
(until we enable snapshot creation).

This patch also introduces a new metadata version number, and compat
code for reading from/writing to older versions - this isn't a forced
upgrade (yet).

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:57 -04:00
Kent Overstreet
73590619ec bcachefs: Don't unconditially version_upgrade in initialize
This is mkfs's job. Also, clean up the handling of feature bits some.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:56 -04:00
Kent Overstreet
87a432f5d7 bcachefs: Kill reflink option
An option was added to control whether reflink support was on or off
because for a long time, reflink + inline data extent support was
missing - but that's since been fixed, so we can drop the option now.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:56 -04:00
Kent Overstreet
7d6f07edc2 bcachefs: Fix compat code for superblock
The bkey compat code wasn't being run for btree roots in the superblock
clean section - this patch fixes it to use the journal entry validate
code.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:55 -04:00
Kent Overstreet
2436cb9fad bcachefs: Use x-macros for more enums
This patch standardizes all the enums that have associated string tables
(probably more enums should have string tables).

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:55 -04:00
Kent Overstreet
41f8b09edc bcachefs: Rename BTREE_ID enums for consistency with other enums
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:55 -04:00
Kent Overstreet
79f88eba01 bcachefs: Rename KEY_TYPE_whiteout -> KEY_TYPE_hash_whiteout
Snapshots are going to need a different whiteout key type. Also, switch
to using BCH_BKEY_TYPES() to define the bkey value accessors.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:55 -04:00
Kent Overstreet
19dd3172b0 bcachefs: Use x-macros for compat feature bits
This is to generate strings for them, so that we can print them out.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:54 -04:00
Kent Overstreet
e01dacf76c bcachefs: Fix bkey format generation for 32 bit fields
Having a packed format that can represent a field larger than the
unpacked type breaks bkey_packed_successor() assertions - we need to fix this to start using the snapshot filed.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:54 -04:00
Kent Overstreet
a4805d6672 bcachefs: Scan for old btree nodes if necessary on mount
We dropped support for !BTREE_NODE_NEW_EXTENT_OVERWRITE but it turned
out there were people who still had filesystems with btree nodes in that
format in the wild. This adds a new compat feature that indicates we've
scanned for and rewritten nodes in the old format, and does that scan at
mount time if the option isn't set.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:54 -04:00
Kent Overstreet
8042b5b715 bcachefs: Extents may now cross btree node boundaries
When snapshots arrive, we won't necessarily be able to arbitrarily split
existis - when we need to split an existing extent, we'll have to check
if the extent was overwritten in child snapshots and if so emit a
whiteout for the split in the child snapshot.

Because extents couldn't span btree nodes previously, journal replay
would sometimes have to split existing extents. That's no good anymore,
but fortunately since extent handling has already been lifted above most
of the btree code there's no real need for that rule anymore.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:53 -04:00
Kent Overstreet
180fb49dea bcachefs: Journal updates to dev usage
This eliminates the need to scan every bucket to regenerate dev_usage at
mount time.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:52 -04:00
Kent Overstreet
2abe542087 bcachefs: Persist 64 bit io clocks
Originally, bcachefs - going back to bcache - stored, for each bucket, a
16 bit counter corresponding to how long it had been since the bucket
was read from. But, this required periodically rescaling counters on
every bucket to avoid wraparound. That wasn't an issue in bcache, where
we'd perodically rewrite the per bucket metadata all at once, but in
bcachefs we're trying to avoid having to walk every single bucket.

This patch switches to persisting 64 bit io clocks, corresponding to the
64 bit bucket timestaps introduced in the previous patch with
KEY_TYPE_alloc_v2.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:52 -04:00
Kent Overstreet
7f4e1d5d0f bcachefs: KEY_TYPE_alloc_v2
This introduces a new version of KEY_TYPE_alloc, which uses the new
varint encoding introduced for inodes. This means we'll eventually be
able to support much larger bucket sizes (for SMR devices), and the
read/write time fields are expanded to 64 bits - which will be used in
the next patch to get rid of the periodic rescaling of those fields.

Also, for buckets that are members of erasure coded stripes, this adds
persistent fields for the index of the stripe they're members of and the
stripe redundancy. This is part of work to get rid of having to scan and
read into memory the alloc and stripes btrees at mount time.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:52 -04:00
Kent Overstreet
d042b0402c bcachefs: Add an option for metadata_target
Also, make journal writes obey foreground_target and metadata_target.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:52 -04:00
Kent Overstreet
51d2dfb82d bcachefs: Add BTREE_PTR_RANGE_UPDATED
This is so that when we discover btree topology issues, we can just
update the pointer to a btree node and signal btree read path that the
min/max keys in the node header should be updated from the node pointer.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:52 -04:00
Kent Overstreet
07a1006ae8 bcachefs: Reduce/kill BKEY_PADDED use
With various newer key types - stripe keys, inline data extents - the
old approach of calculating the maximum size of the value is becoming
more and more error prone. Better to switch to bkey_on_stack, which can
dynamically allocate if necessary to handle any size bkey.

In particular we also want to get rid of BKEY_EXTENT_VAL_U64s_MAX.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:50 -04:00
Kent Overstreet
81d8599e19 bcachefs: Don't read existing stripes synchronously in write path
Previously, in the stripe creation path, when reusing an existing stripe
we'd read the existing stripe synchronously - ouch.

Now, we allocate two stripe bufs if we're using an existing stripe, so
that we can do the read asynchronously - and, we read the full stripe so
that we can run recovery, if necessary.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:50 -04:00
Kent Overstreet
ffb7c3d370 bcachefs: Add BCH_BKEY_PTRS_MAX
This now means "the maximum number of pointers within a bkey" - and
bch_devs_list is updated to use it instead of BCH_REPLICAS_MAX, since
stripes can contain more than BCH_REPLICAS_MAX pointers.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:50 -04:00
Kent Overstreet
adbcada43f bcachefs: Don't require flush/fua on every journal write
This patch adds a flag to journal entries which, if set, indicates that
they weren't done as flush/fua writes.

 - non flush/fua journal writes don't update last_seq (i.e. they don't
   free up space in the journal), thus the journal free space
   calculations now check whether nonflush journal writes are currently
   allowed (i.e. are we low on free space, or would doing a flush write
   free up a lot of space in the journal)

 - write_delay_ms, the user configurable option for when open journal
   entries are automatically written, is now interpreted as the max
   delay between flush journal writes (default 1 second).

 - bch2_journal_flush_seq_async is changed to ensure a flush write >=
   the requested sequence number has happened

 - journal read/replay must now ignore, and blacklist, any journal
   entries newer than the most recent flush entry in the journal. Also,
   the way the read_entire_journal option is handled has been improved;
   struct journal_replay now has an entry, 'ignore', for entries that
   were read but should not be used.

 - assorted refactoring and improvements related to journal read in
   journal_io.c and recovery.c

Previously, we'd have to issue a flush/fua write every time we
accumulated a full journal entry - typically the bucket size. Now we
need to issue them much less frequently: when an fsync is requested, or
it's been more than write_delay_ms since the last flush, or when we need
to free up space in the journal. This is a significant performance
improvement on many write heavy workloads.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:49 -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
801a3de642 bcachefs: Indirect inline data extents
When inline data extents were added, reflink was forgotten about - we
need indirect inline data extents for reflink + inline data to work
correctly.

This patch adds them, and a new feature bit that's flipped when they're
used.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:45 -04:00
Kent Overstreet
af4d05c46b bcachefs: Account for stripe parity sectors separately
Instead of trying to charge EC parity to the data within the stripe
(which is subject to rounding errors), let's charge it to the stripe
itself. It should also make -ENOSPC issues easier to deal with if we
charge for parity blocks up front, and means we can also make more fine
grained accounting available to the user.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:45 -04:00
Kent Overstreet
89fd25be70 bcachefs: Use x-macros for data types
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:42 -04:00
Kent Overstreet
36b8372b59 bcachefs: Add an option to disable reflink support
Reflink might be buggy, so we're adding an option so users can help
bisect what's going on.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:40 -04:00
Kent Overstreet
39fb2983c5 bcachefs: Kill bkey_type_successor
Previously, BTREE_ID_INODES was special - inodes were indexed by the
inode field, which meant the offset field of struct bpos wasn't used,
which led to special cases in e.g. the btree iterator code.

Now, inodes in the inodes btree are indexed by the offset field.

Also: prevously min_key was special for extents btrees, min_key for
extents would equal max_key for the previous node. Now, min_key =
bkey_successor() of the previous node, same as non extent btrees.

This means we can completely get rid of
btree_type_sucessor/predecessor.

Also make some improvements to the metadata IO validate/compat code.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:37 -04:00
Kent Overstreet
6357d6071f bcachefs: Journal updates to interior nodes
Previously, the btree has always been self contained and internally
consistent on disk without anything from the journal - the journal just
contained pointers to the btree roots.

However, this meant that btree node split or compact operations - i.e.
anything that changes btree node topology and involves updates to
interior nodes - would require that interior btree node to be written
immediately, which means emitting a btree node write that's mostly empty
(using 4k of space on disk if the filesystemm blocksize is 4k to only
write perhaps ~100 bytes of new keys).

More importantly, this meant most btree node writes had to be FUA, and
consumer drives have a history of slow and/or buggy FUA support - other
filesystes have been bit by this.

This patch changes the interior btree update path to journal updates to
interior nodes, after the writes for the new btree nodes have completed.
Best of all, it turns out to simplify the interior node update path
somewhat.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:37 -04:00
Kent Overstreet
e3e464ac6d bcachefs: Move extent overwrite handling out of core btree code
Ever since the btree code was first written, handling of overwriting
existing extents - including partially overwriting and splittin existing
extents - was handled as part of the core btree insert path. The modern
transaction and iterator infrastructure didn't exist then, so that was
the only way for it to be done.

This patch moves that outside of the core btree code to a pass that runs
at transaction commit time.

This is a significant simplification to the btree code and overall
reduction in code size, but more importantly it gets us much closer to
the core btree code being completely independent of extents and is
important prep work for snapshots.

This introduces a new feature bit; the old and new extent update models
are incompatible when the filesystem needs journal replay.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:36 -04:00
Kent Overstreet
b807a0c8ba bcachefs: BCH_SB_FEATURES_ALL
BCH_FEATURE_btree_ptr_v2 wasn't getting set on new filesystems, oops

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:35 -04:00
Kent Overstreet
548b3d209f bcachefs: btree_ptr_v2
Add a new btree ptr type which contains the sequence number (random 64
bit cookie, actually) for that btree node - this lets us verify that
when we read in a btree node it really is the btree node we wanted.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:35 -04:00
Kent Overstreet
ab05de4ce4 bcachefs: Track incompressible data
This fixes the background_compression option: wihout some way of marking
data as incompressible, rebalance will keep rewriting incompressible
data over and over.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:34 -04:00
Kent Overstreet
bcd6f3e06f bcachefs: Use KEY_TYPE_deleted whitouts for extents
Previously, partial overwrites of existing extents were handled
implicitly by the btree code; when reading in a btree node, we'd do a
mergesort of the different bsets and detect and fix partially
overlapping extents during that mergesort.

That approach won't work with snapshots: this changes extents to work
like regular keys as far as the btree code is concerned, where a 0 size
KEY_TYPE_deleted whiteout will completely overwrite an existing extent.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:33 -04:00