Extent merging is currently broken, and will be reimplemented
differently soon - right now it only happens when btree nodes are being
compacted, which makes it difficult to test.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Recently the extent update path started emmiting 0 size whiteouts on
extent overwrite, as part of transitioning to moving extent handling
out of the core btree code.
Unfortunately, this broke the old code path that handles overlapping
extents when reading in btree nodes - it relies on sorting incomming
extents by start position, but the 0 size whiteouts broke that ordering.
Skipping over them before the main algorithm sees them fixes this.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This fixes a nasty memory corruption with other threads that are still
reading the btree node being compacted.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
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>
Long overdue cleanup - this converts btree_node_iter_large uses to
sort_iter.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
The whiteout compaction path - as opposed to just dropping whiteouts -
is now only needed for extents, and soon will only be needed for extent
btree nodes in the old format.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This changes bch2_cut_front and bch2_cut_back so that they're able to
shorten the size of the value, and it also changes the extent update
path to update the accounting in the btree node when this happens.
When the size of the value is shortened, they zero out the space that's
no longer used, so it's interpreted as noops (as implemented in the last
patch).
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
For upcoming inline data extents, we're going to need to be able to
shorten the value of existing bkeys in the btree - and to make that work
we're going to be able to need to pad out the space the value previously
took up with something.
This patch changes the various code that iterates over bkeys to handle
k->u64s == 0 as meaning "skip the next 8 bytes".
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This implements code for storing small bkeys on the stack and allocating
out of a mempool if they're too big.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Prep work for extents with inline data
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
bch2_bkey_normalize() modifies the value, and we were modifying the
original value in the src btree node - but, we're called without a write
lock held on the src node. Oops...
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
this lets us get rid of a lot of extra switch statements - in a lot of
places we dispatch on the btree node type, and then the key type, so
this is a nice cleanup across a lot of code.
Also improve the on disk format versioning stuff.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
