153 Commits

Author SHA1 Message Date
Kent Overstreet
84c72755b9 bcachefs: Initialize ec work structs early
We need to ensure that work structs in bch_fs always get initialized -
otherwise an error in filesystem initialization can pop a warning in the
workqueue code when we try to cancel a work struct that wasn't
initialized.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:31 -04:00
Kent Overstreet
ce6201c456 bcachefs: Use a genradix for reading journal entries
Previously, the journal read path used a linked list for storing the
journal entries we read from disk. But there's been a bug that's been
causing journal_flush_delay to incorrectly be set to 0, leading to far
more journal entries than is normal being written out, which then means
filesystems are no longer able to start due to the O(n^2) behaviour of
inserting into/searching that linked list.

Fix this by switching to a radix tree.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:30 -04:00
Kent Overstreet
822835ffea bcachefs: Fold bucket_state in to BCH_DATA_TYPES()
Previously, we were missing accounting for buckets in need_gc_gens and
need_discard states. This matters because buckets in those states need
other btree operations done before they can be used, so they can't be
conuted when checking current number of free buckets against the
allocation watermark.

Also, we weren't directly counting free buckets at all. Now, data type 0
== BCH_DATA_free, and free buckets are counted; this means we can get
rid of the separate (poorly defined) count of unavailable buckets.

This is a new on disk format version, with upgrade and fsck required for
the accounting changes.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:30 -04:00
Kent Overstreet
e1effd42a1 bcachefs: More improvements for alloc info checks
- Move checks for whether the device & bucket are valid from the
   .key_invalid method to bch2_check_alloc_key(). This is because
   .key_invalid() is called on keys that may no longer exist (post
   journal replay), which is a problem when removing/resizing devices.

 - We weren't checking the need_discard btree to ensure that every set
   bucket has a corresponding alloc key. This refactors the code for
   checking the freespace btree, so that it now checks both.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:30 -04:00
Kent Overstreet
59cc38b8d4 bcachefs: New discard implementation
In the old allocator code, buckets would be discarded just prior to
being used - this made sense in bcache where we were discarding buckets
just after invalidating the cached data they contain, but in a
filesystem where we typically have more free space we want to be
discarding buckets when they become empty.

This patch implements the new behaviour - it checks the need_discard
btree for buckets awaiting discards, and then clears the appropriate
bit in the alloc btree, which moves the buckets to the freespace btree.

Additionally, discards are now enabled by default.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:29 -04:00
Kent Overstreet
f25d8215f4 bcachefs: Kill allocator threads & freelists
Now that we have new persistent data structures for the allocator, this
patch converts the allocator to use them.

Now, foreground bucket allocation uses the freespace btree to find
buckets to allocate, instead of popping buckets off the freelist.

The background allocator threads are no longer needed and are deleted,
as well as the allocator freelists. Now we only need background tasks
for invalidating buckets containing cached data (when we are low on
empty buckets), and for issuing discards.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:29 -04:00
Kent Overstreet
c6b2826cd1 bcachefs: Freespace, need_discard btrees
This adds two new btrees for the upcoming allocator rewrite: an extents
btree of free buckets, and a btree for buckets awaiting discards.

We also add a new trigger for alloc keys to keep the new btrees up to
date, and a compatibility path to initialize them on existing
filesystems.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:29 -04:00
Kent Overstreet
b17d3cec14 bcachefs: Run btree updates after write out of write_point
In the write path, after the write to the block device(s) complete we
have to punt to process context to do the btree update.

Instead of using the work item embedded in op->cl, this patch switches
to a per write-point work item. This helps with two different issues:

 - lock contention: btree updates to the same writepoint will (usually)
   be updating the same alloc keys
 - context switch overhead: when we're bottlenecked on btree updates,
   having a thread (running out of a work item) checking the write point
   for completed ops is cheaper than queueing up a new work item and
   waking up a kworker.

In an arbitrary benchmark, 4k random writes with fio running inside a
VM, this patch resulted in a 10% improvement in total iops.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:29 -04:00
Kent Overstreet
74b33393db bcachefs: x-macro metadata version enum
Now we've got strings for metadata versions - this changes
bch2_sb_to_text() and our mount log message to use it.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:28 -04:00
Kent Overstreet
5521b1dfa2 bcachefs: Convert bch2_sb_to_text to master option list
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>
2023-10-22 17:09:27 -04:00
Daniel Hill
102a6a8f69 bcachefs: respect superblock discard flag.
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>
2023-10-22 17:09:26 -04:00
Kent Overstreet
fa8e94faee bcachefs: Heap allocate printbufs
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>
2023-10-22 17:09:25 -04:00
Kent Overstreet
b66b2bc0f6 bcachefs: Revert "Ensure journal doesn't get stuck in nochanges mode"
This patch was originally to work around the journal geting stuck in
nochanges mode - but that was just a hack, we needed to fix the actual
bug. It should be fixed now, so revert it.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:25 -04:00
Kent Overstreet
bf7e49a4ae bcachefs: Change bch2_dev_lookup() to not use lookup_bdev()
bch2_dev_lookup() is used from the extended attribute set methods, for
setting the target options, where we're already holding an inode lock -
it turns out pathname lookups also take inode locks, so that was
susceptible to deadlocks.

Fortunately we already stash the device name in ca->name. This does
change user-visible behaviour though: instead of specifying e.g.
/dev/sda1, user must now specify sda1.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:24 -04:00
Kent Overstreet
c45c866761 bcachefs: bch2_gc_gens() no longer uses bucket array
Like the previous patches, this converts bch2_gc_gens() to use the alloc
btree directly, and private arrays of generation numbers for its own
recalculation of oldest_gen.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:23 -04:00
Kent Overstreet
7c8f6f980d bcachefs: btree_id_cached()
Add a new helper that returns true if the given btree ID uses the btree
key cache. This enables some new cleanups, since the helper can check
the options for whether caching is enabled on a given btree.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:23 -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
9b6e2f1e70 Revert "bcachefs: Delete some obsolete journal_seq_blacklist code"
This reverts commit f95b61228efd04c9c158123da5827c96e9773b29.

It turns out, we're seeing filesystems in the wild end up with
blacklisted btree node bsets - this should not be happening, and until
we understand why and fix it we need to keep this code around.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:21 -04:00
Kent Overstreet
03ea3962ab bcachefs: Log & error message improvements
- Add a shim uuid_unparse_lower() in the kernel, since %pU doesn't work
   in userspace

 - We don't need to print the bcachefs: or the filesystem name prefix in
   userspace

 - Improve a few error messages

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:21 -04:00
Kent Overstreet
efe68e1d65 bcachefs: Improved superblock-related error messages
This patch converts bch2_sb_validate() and the .validate methods for the
various superblock sections to take printbuf, to which they can print
detailed error messages, including printing the entire section that was
invalid.

This is a great improvement over the previous situation, where we could
only return static strings that didn't have precise information about
what was wrong.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:21 -04:00
Kent Overstreet
eacb2574f0 bcachefs: bch_dev->dev
Add a field to bch_dev for the dev_t of the underlying block device -
this fixes a null ptr deref in tracepoints.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:21 -04:00
Kent Overstreet
d248ee5637 bcachefs: Add iter_flags arg to bch2_btree_delete_range()
Will be used by the new snapshot tests, to pass in
BTREE_ITER_ALL_SNAPSHOTS.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:20 -04:00
Kent Overstreet
e853692588 bcachefs: Improve error messages in device add path
This converts the error messages in the device add to a better style,
and adds some missing ones.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:20 -04:00
Kent Overstreet
04f0f77df2 bcachefs: Delete some obsolete journal_seq_blacklist code
Since metadata version bcachefs_metadata_version_btree_ptr_sectors_written,
we haven't needed the journal seq blacklist mechanism for ignoring
blacklisted btree node writes - we now only need it for ignoring journal
entries that were written after the newest flush journal entry, and then
we only need to keep those blacklist entries around until journal replay
is finished.

That means we can delete the code for scanning btree nodes to GC
journal_seq_blacklist entries.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:20 -04:00
Kent Overstreet
77170d0dd7 bcachefs: bch2_bucket_alloc_new_fs() no longer depends on bucket marks
Now that bch2_bucket_alloc_new_fs() isn't looking at bucket marks to
decide what buckets are eligible to allocate, we can clean up the
filesystem initialization and device add paths. Previously, we had to
use ancient code to mark superblock/journal buckets in the in memory
bucket marks as we allocated them, and then zero that out and re-do that
marking using the newer transational bucket mark paths. Now, we can
simply delete the in-memory bucket marking.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:19 -04:00
Kent Overstreet
09943313d7 bcachefs: Rewrite bch2_bucket_alloc_new_fs()
This changes bch2_bucket_alloc_new_fs() to a simple bump allocator that
doesn't need to use the in memory bucket array, part of a larger patch
series to entirely get rid of the in memory bucket array, except for
gc/fsck.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:19 -04:00
Kent Overstreet
8244f3209b bcachefs: Option improvements
This adds flags for options that must be a power of two (block size and
btree node size), and options that are stored in the superblock as a
power of two (encoded extent max).

Also: options are now stored in memory in the same units they're
displayed in (bytes): we now convert when getting and setting from the
superblock.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:19 -04:00
Kent Overstreet
991ba02112 bcachefs: Add more time_stats
This adds more latency/event measurements and breaks some apart into
more events. Journal writes are broken apart into flush writes and
noflush writes, btree compactions are broken out from btree splits,
btree mergers are added, as well as btree_interior_updates - foreground
and total.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:18 -04:00
Kent Overstreet
2430e72f42 bcachefs: Convert journal sysfs params to regular options
This converts journal_write_delay, journal_flush_disabled, and
journal_reclaim_delay to normal filesystems options, and also adds them
to the superblock.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:18 -04:00
Kent Overstreet
e2b605601a bcachefs: Clean up error reporting in the startup path
It used to be that error reporting in the startup path was done by
returning strings describing the error, but that turned out to be a
rather silly idea - if there's something we can describe about the
error, just print it right away.

This converts a good chunk of code to returning error codes, as is more
typical style.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:16 -04:00
Chris Webb
7be9ab637f bcachefs: Return -ENOKEY/EINVAL when mount decryption fails
bch2_fs_encryption_init() correctly passes back -ENOKEY from request_key()
when no unlock key is found, or -EINVAL if superblock decryption fails
because of an invalid key. However, these get absorbed into a generic NULL
return from bch2_fs_alloc() and later returned to user space as -ENOMEM,
leading to a misleading error from mount(1):

  mount(2) system call failed: Out of memory.

Return explicit error pointers out of bch2_fs_alloc() and handle them in
both callers, so the user instead sees

  mount(2) system call failed: Required key not available.

when attempting to mount a filesystem which is still locked.

Signed-off-by: Chris Webb <chris@arachsys.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:16 -04:00
Kent Overstreet
fae1157d18 bcachefs: Ensure journal doesn't get stuck in nochanges mode
This tweaks the journal code to always act as if there's space available
in nochanges mode, when we're not going to be doing any writes. This
helps in recovering filesystems that won't mount because they need
journal replay and the journal has gotten stuck.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:15 -04:00
Kent Overstreet
f124345e2b bcachefs: Drop bch2_journal_meta() call when going RW
Back when we relied on the journal sequence number blacklist machinery
for consistency between btree and the journal, we needed to ensure a new
journal entry was written before any btree writes were done. But, this
had the side effect of consuming some space in the journal prior to
doing journal replay - which could lead to a very wedged filesystem,
since we don't yet have a way to grow the journal prior to going RW.

Fortunately, the journal sequence number blacklist machinery isn't
needed anymore, as btree node pointers now record the numer of sectors
currently written to that node - that code should all be ripped out.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:15 -04:00
Kent Overstreet
114eea75c7 bcachefs: Fix dev accounting after device add
This is a hacky but effective fix to device usage stats for superblock
and journal being wrong on a newly added device (following the comment
that already told us how it needed to be done!)

Reported-by: Chris Webb <chris@arachsys.com>
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:14 -04:00
Kent Overstreet
a9cb0a6706 bcachefs: Fix bch2_dev_remove_alloc()
It was missing a lockrestart_do(), to call bch2_trans_begin() and also
handle transaction restarts.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:13 -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
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
Brett Holman
8dd6ed9451 bcachefs: add progress stats to sysfs
This adds progress stats to sysfs for copygc, rebalance, recovery, and the
cmd_job ioctls.

Signed-off-by: Brett Holman <bholman.devel@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:10 -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
224ec3e677 bcachefs: Don't mark superblocks past end of usable space
bcachefs-tools recently started putting a backup superblock at the end
of the device. This causes a problem if the bucket size doesn't divide
the device size - but we can fix it by just skipping marking that part.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:05 -04:00
Kent Overstreet
c0ebe3e48c bcachefs: Assorted endianness fixes
Found by sparse

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:05 -04:00
Kent Overstreet
9f2772c454 bcachefs: Split out btree_error_wq
We can't use btree_update_wq becuase btree updates may be waiting on
btree writes to complete.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:04 -04:00
Kent Overstreet
731bdd2eff bcachefs: Add a workqueue for btree io completions
Also, clean up workqueue usage - we shouldn't be using system
workqueues, pretty much everything we do needs to be on our own
WQ_MEM_RECLAIM workqueues.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
2023-10-22 17:09:04 -04:00
Kent Overstreet
ef1b20924b bcachefs: Ratelimiting for writeback IOs
Writeback throttling is a kernel config option and not always enabled.
When it's not enabled we need a fallback, to avoid unbounded memory
pinning and work item backlogs.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:03 -04:00
Dan Robertson
ec4ab9d2fc bcachefs: Fix possible null deref on mount
Ensure that the block device pointer in a superblock handle is not
null before dereferencing it in bch2_dev_to_fs. The block device pointer
may be null when mounting a new bcachefs filesystem given another mounted
bcachefs filesystem exists that has at least one device that is offline.

Signed-off-by: Dan Robertson <dan@dlrobertson.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:03 -04:00
Kent Overstreet
3a402c8dab bcachefs: Fix some refcounting bugs
We really need debug mode assertions that ca->ref and ca->io_ref are
used correctly.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:03 -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
4932e07ea0 bcachefs: Fix key cache assertion
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
d62ab355d7 bcachefs: Fix bch2_trans_mark_dev_sb()
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
Kent Overstreet
9d8022db1c bcachefs: Eliminate more PAGE_SIZE uses
In userspace, we don't really have a well defined PAGE_SIZE and shouln't
be relying on it. This is some more incremental work to remove
references to it.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:59 -04:00