This fixes a use-after-free.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

We currently don't track whether snapshot cleanup still needs to finish
(aside from running a full fsck), so it shouldn't be a fsck error yet -
fsck -n after fsck has succesfully completed shouldn't error.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Delete a redundant bch2_snapshot_is_ancestor() check, and convert some
assertions to debug assertions.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Make the overlapping extent check/repair code more self contained.

This is prep work for hopefully reducing key_visible_in_snapshot() usage
here as well, and also includes a nice performance optimization to not
check ref_visible2() unless the extents potentially overlap.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

This changes the main part of check_extents(), that checks the extent
against the corresponding inode, to not use key_visible_in_snapshot().

key_visible_in_snapshot() has to iterate over the list of ancestor
overwrites repeatedly calling bch2_snapshot_is_ancestor(), so this is a
significant performance improvement.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

More prep work for reducing key_visible_in_snapshot() usage - this
rearranges how KEY_TYPE_whitout keys are handled, so that they can be
marked off in inode_warker->inode->seen_this_pos.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

We only want to synthesize an inode for the current snapshot ID for non
whiteouts - this refactoring lets us call walk_inode() earlier and clean
up some control flow.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Minor refactoring/dead code deletion, prep work for reworking
check_extent() to avoid key_visible_in_snapshot().
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

This improves the repair path for overlapping extents - we now verify
that we find in the btree the overlapping extents that the algorithm
detected, and fail the fsck run with a more useful error if it doesn't
match.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Prep work for changing check_extent() to avoid
key_visible_in_snapshot() - this adds the state to track whether an
inode has seen an extent at this pos.
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>

Some minor fixes to not print errors that are actually due to a verson
upgrade.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Further optimization for bch2_snapshot_is_ancestor(). We add a small
inline bitmap to snapshot_t, which indicates which of the next 128
snapshot IDs are ancestors of the current id - eliminating the last few
iterations of the loop in bch2_snapshot_is_ancestor().
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Mark these caches as reclaimable, so that available memory is correctly
reported when there is a lot of cached inodes.

Note that more work is needed - you should add __GFP_RECLAIMABLE to some
of the kmalloc calls, so that they are allocated from the "kmalloc-rcl-*"
caches.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

This allows including a compression level when specifying a compression
type, e.g.
  compression=zstd:15

Values from 1 through 15 indicate compression levels, 0 or unspecified
indicates the default.

For LZ4, values 3-15 specify that the HC algorithm should be used.

Note that for compatibility, extents themselves only include the
compression type, not the compression level. This means that specifying
the same compression algorithm but different compression levels for the
compression and background_compression options will have no effect.

XXX: perhaps we could add a warning for this
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

The upper 4 bits are for compression level.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

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

Before, it was parsed as a bool but internally it was really an enum:
this lets us pass in all the possible values.

But we special case the option parsing: no supplied value is parsed as
FSCK_FIX_yes, to match the previous behaviour.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Minor refactoring to get rid of some unneeded token pasting.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

This switches the generic radix tree for the in-memory table of snapshot
nodes to a simple rcu array. This means we have to add new locking to
deal with reallocations, but is faster than traversing the radix tree.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

We haven't hooked up dynamic fault injection quite yet, but we will soon
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

In userspace, we want to be able to switch to buffered IO when we're
dealing with an image on a filesystem/device that doesn't support the
blocksize the filesystem was formatted with.

This plumbs through !opts.direct_io -> FMODE_BUFFERED, which will be
supported by the shim version of blkdev_get_by_path() in -tools, and it
adds a fallback to disable direct IO and retry for userspace.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Previously, fallocate would only check the state of the extents btree
when determining if we need to create a reservation.

But the page cache might already have dirty data or a disk reservation.
This changes __bchfs_fallocate() to call bch2_seek_pagecache_hole() to
check for this.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

With "bcachefs: Snapshot depth, skiplist fields", we now can't run data
move operations until after bch2_check_snapshots() is complete.

Ideally we'd have the copygc (and rebalance) threads wait until
c->curr_recovery_pass has advanced, but the waitlist handling is tricky
- so for now, move starting copygc back to read_write_late().
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

fixes
./include/linux/stddef.h:8:14: error: positional initialization of field in ‘struct’ declared with ‘designated_init’ attribute [-Werror=designated-init]
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

This extents KEY_TYPE_snapshot to include some new fields:
 - depth, to indicate depth of this particular node from the root
 - skip[3], skiplist entries for quickly walking back up to the root

These are to improve bch2_snapshot_is_ancestor(), making it O(ln(n))
instead of O(n) in the snapshot tree depth.

Skiplist nodes are picked at random from the set of ancestor nodes, not
some fixed fraction.

This introduces bcachefs_metadata_version 1.1, snapshot_skiplists.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Now that we've got forward compatibility sorted out, we should be doing
more frequent version upgrades in the future.

To avoid having to run a full fsck for every version upgrade, this
improves the BCH_METADATA_VERSIONS() table to explicitly specify a
bitmask of recovery passes to run when upgrading to or past a given
version.

This means we can also delete PASS_UPGRADE().
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Add some new helpers, and fix upgrade/downgrade in bch2_fs_initialize().
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

We're not supposed to block if BTREE_INSERT_JOURNAL_RECLAIM && watermark
!= BCH_WATERMARK_reclaim.

This should really be a separate BTREE_INSERT_NONBLOCK flag - add some
comments to that effect, it's not important for this patch.

btree write buffer flush depends on this behaviour though - the first
loop tries to flush sequentially, which doesn't free up space in the
journal optimally. If that can't proceed we bail out and flush in
journal order - that won't work if we're blocked instead of returning an
error.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

This introduces major/minor versioning to the superblock version number.
Major version number changes indicate incompatible releases; we can move
forward to a new major version number, but not backwards. Minor version
numbers indicate compatible changes - these add features, but can still
be mounted and used by old versions.

With the recent patches that make it possible to roll out new btrees and
key types without breaking compatibility, we should be able to roll out
most new features without incompatible changes.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

We've been seeing assertions pop that indicate the btree node cache or
key cache have dirty items when we just did a clean shutdown.

Add some more assertions so we can catch this when we're dirtying items.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Fixes fstests generic/728
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Inline it into the only caller
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

We were freeing open buckets on the writepoint list, but forgetting to
take them off the writepoint list - whoops
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

As discussed on list, bcachefs is going to be marked as experimental for
a few releases, until the inevitable tide of new bug reports subsides.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Recovery and fsck have many different passes/jobs to do, which always
run in the same order - but not all of them run all the time. Some are
for fsck, some for unclean shutdown, some for version upgrades.

This adds some new structure: a defined list of recovery passes that we
can run in a loop, as well as consolidating the log messages.

The main benefit is consolidating the "should run this recovery pass"
logic, as well as cleaning up the "this recovery pass has finished"
state; instead of having a bunch of ad-hoc state bits in c->flags, we've
now got c->curr_recovery_pass.

By consolidating the "should run this recovery pass" logic, in the
future on disk format upgrades will be able to say "upgrading to this
version requires x passes to run", instead of forcing all of fsck to
run.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

For the upcoming enumeration of recovery passes, we need all recovery
passes to be called the same way - including journal replay.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

This folds bch2_bucket_gens_read() into bch2_alloc_read(), doing the
version check there.

This is prep work for enumarating all recovery passes: we need some
cleanup first to make calling all the recovery passes consistent.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

We need to always call bch2_replicas_gc_end() after we've called
bch2_replicas_gc_start(), else we leave state around that needs to be
cleaned up.

Partial fix for: https://github.com/koverstreet/bcachefs/issues/560Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>