/*
* Returns true if l > r - unless l == r, in which case returns true if l is
* older than r.
*
* Necessary for btree_sort_fixup() - if there are multiple keys that compare
* equal in different sets, we have to process them newest to oldest.
*/
static bool bch_extent_sort_cmp(struct btree_iter_set l,
struct btree_iter_set r)
{
int64_t c = bkey_cmp(&START_KEY(l.k), &START_KEY(r.k));
return c ? c > 0 : l.k < r.k;
}
static struct bkey *bch_extent_sort_fixup(struct btree_iter *iter,
struct bkey *tmp)
{
while (iter->used > 1) {
struct btree_iter_set *top = iter->data, *i = top + 1;
if (iter->used > 2 &&
bch_extent_sort_cmp(i[0], i[1]))
i++;
if (bkey_cmp(top->k, &START_KEY(i->k)) <= 0)
break;
if (!KEY_SIZE(i->k)) {
sort_key_next(iter, i);
heap_sift(iter, i - top, bch_extent_sort_cmp);
continue;
}
if (top->k > i->k) {
if (bkey_cmp(top->k, i->k) >= 0)
sort_key_next(iter, i);
else
bch_cut_front(top->k, i->k);
heap_sift(iter, i - top, bch_extent_sort_cmp);
} else {
/* can't happen because of comparison func */
BUG_ON(!bkey_cmp(&START_KEY(top->k), &START_KEY(i->k)));
if (bkey_cmp(i->k, top->k) < 0) {
bkey_copy(tmp, top->k);
bch_cut_back(&START_KEY(i->k), tmp);
bch_cut_front(i->k, top->k);
heap_sift(iter, 0, bch_extent_sort_cmp);
return tmp;
} else {
bch_cut_back(&START_KEY(i->k), top->k);
}
}
}
return NULL;
}
static bool bch_extent_insert_fixup(struct btree_keys *b,
struct bkey *insert,
struct btree_iter *iter,
struct bkey *replace_key)
{
struct cache_set *c = container_of(b, struct btree, keys)->c;
uint64_t old_offset;
unsigned old_size, sectors_found = 0;
BUG_ON(!KEY_OFFSET(insert));
BUG_ON(!KEY_SIZE(insert));
while (1) {
struct bkey *k = bch_btree_iter_next(iter);
if (!k)
break;
if (bkey_cmp(&START_KEY(k), insert) >= 0) {
if (KEY_SIZE(k))
break;
else
continue;
}
if (bkey_cmp(k, &START_KEY(insert)) <= 0)
continue;
old_offset = KEY_START(k);
old_size = KEY_SIZE(k);
/*
* We might overlap with 0 size extents; we can't skip these
* because if they're in the set we're inserting to we have to
* adjust them so they don't overlap with the key we're
* inserting. But we don't want to check them for replace
* operations.
*/
if (replace_key && KEY_SIZE(k)) {
/*
* k might have been split since we inserted/found the
* key we're replacing
*/
unsigned i;
uint64_t offset = KEY_START(k) -
KEY_START(replace_key);
/* But it must be a subset of the replace key */
if (KEY_START(k) < KEY_START(replace_key) ||
KEY_OFFSET(k) > KEY_OFFSET(replace_key))
goto check_failed;
/* We didn't find a key that we were supposed to */
if (KEY_START(k) > KEY_START(insert) + sectors_found)
goto check_failed;
if (!bch_bkey_equal_header(k, replace_key))
goto check_failed;
/* skip past gen */
offset <<= 8;
BUG_ON(!KEY_PTRS(replace_key));
for (i = 0; i < KEY_PTRS(replace_key); i++)
if (k->ptr[i] != replace_key->ptr[i] + offset)
goto check_failed;
sectors_found = KEY_OFFSET(k) - KEY_START(insert);
}
if (bkey_cmp(insert, k) < 0 &&
bkey_cmp(&START_KEY(insert), &START_KEY(k)) > 0) {
/*
* We overlapped in the middle of an existing key: that
* means we have to split the old key. But we have to do
* slightly different things depending on whether the
* old key has been written out yet.
*/
struct bkey *top;
bch_subtract_dirty(k, c, KEY_START(insert),
KEY_SIZE(insert));
if (bkey_written(b, k)) {
/*
* We insert a new key to cover the top of the
* old key, and the old key is modified in place
* to represent the bottom split.
*
* It's completely arbitrary whether the new key
* is the top or the bottom, but it has to match
* up with what btree_sort_fixup() does - it
* doesn't check for this kind of overlap, it
* depends on us inserting a new key for the top
* here.
*/
top = bch_bset_search(b, bset_tree_last(b),
insert);
bch_bset_insert(b, top, k);
} else {
BKEY_PADDED(key) temp;
bkey_copy(&temp.key, k);
bch_bset_insert(b, k, &temp.key);
top = bkey_next(k);
}
bch_cut_front(insert, top);
bch_cut_back(&START_KEY(insert), k);
bch_bset_fix_invalidated_key(b, k);
goto out;
}
if (bkey_cmp(insert, k) < 0) {
bch_cut_front(insert, k);
} else {
if (bkey_cmp(&START_KEY(insert), &START_KEY(k)) > 0)
old_offset = KEY_START(insert);
if (bkey_written(b, k) &&
bkey_cmp(&START_KEY(insert), &START_KEY(k)) <= 0) {
/*
* Completely overwrote, so we don't have to
* invalidate the binary search tree
*/
bch_cut_front(k, k);
} else {
__bch_cut_back(&START_KEY(insert), k);
bch_bset_fix_invalidated_key(b, k);
}
}
bch_subtract_dirty(k, c, old_offset, old_size - KEY_SIZE(k));
}
check_failed:
if (replace_key) {
if (!sectors_found) {
return true;
} else if (sectors_found < KEY_SIZE(insert)) {
SET_KEY_OFFSET(insert, KEY_OFFSET(insert) -
(KEY_SIZE(insert) - sectors_found));
SET_KEY_SIZE(insert, sectors_found);
}
}
out:
if (KEY_DIRTY(insert))
bcache_dev_sectors_dirty_add(c, KEY_INODE(insert),
KEY_START(insert),
KEY_SIZE(insert));
return false;
}
static bool skipped_backwards(struct btree *b, struct bkey *k)
{
return bkey_cmp(k, (!b->level)
? &START_KEY(bkey_next(k))
: bkey_next(k)) > 0;
}
