bcachefs: Improve bch2_check_alloc_info()

This factors out a new helper from bch2_dev_freespace_init(),
bch2_get_key_or_hole(), and uses it in bch2_check_alloc_info(): we're
now able to process holes in the alloc btree as ranges, instead of one
bucket at a time.

This will improve fsck performance on new filesystems, or filesystems
where not every bucket has been used yet.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This commit is contained in:
Kent Overstreet 2022-11-30 13:25:17 -05:00
parent cc65f56599
commit d23124c757

View file

@ -735,7 +735,106 @@ int bch2_trans_mark_alloc(struct btree_trans *trans,
return 0;
}
/*
* This synthesizes deleted extents for holes, similar to BTREE_ITER_SLOTS for
* extents style btrees, but works on non-extents btrees:
*/
struct bkey_s_c bch2_get_key_or_hole(struct btree_iter *iter, struct bpos end, struct bkey *hole)
{
struct bkey_s_c k = bch2_btree_iter_peek_slot(iter);
if (bkey_err(k))
return k;
if (k.k->type) {
return k;
} else {
struct btree_iter iter2;
struct bpos next;
bch2_trans_copy_iter(&iter2, iter);
k = bch2_btree_iter_peek_upto(&iter2,
bkey_min(bkey_min(end,
iter->path->l[0].b->key.k.p),
POS(iter->pos.inode, iter->pos.offset + U32_MAX - 1)));
next = iter2.pos;
bch2_trans_iter_exit(iter->trans, &iter2);
BUG_ON(next.offset >= iter->pos.offset + U32_MAX);
if (bkey_err(k))
return k;
bkey_init(hole);
hole->p = iter->pos;
bch2_key_resize(hole, next.offset - iter->pos.offset);
return (struct bkey_s_c) { hole, NULL };
}
}
static bool next_bucket(struct bch_fs *c, struct bpos *bucket)
{
struct bch_dev *ca;
unsigned iter;
if (bch2_dev_bucket_exists(c, *bucket))
return true;
if (bch2_dev_exists2(c, bucket->inode)) {
ca = bch_dev_bkey_exists(c, bucket->inode);
if (bucket->offset < ca->mi.first_bucket) {
bucket->offset = ca->mi.first_bucket;
return true;
}
bucket->inode++;
bucket->offset = 0;
}
rcu_read_lock();
iter = bucket->inode;
ca = __bch2_next_dev(c, &iter, NULL);
if (ca)
bucket->offset = ca->mi.first_bucket;
rcu_read_unlock();
return ca != NULL;
}
struct bkey_s_c bch2_get_key_or_real_bucket_hole(struct btree_iter *iter, struct bkey *hole)
{
struct bch_fs *c = iter->trans->c;
struct bkey_s_c k;
again:
k = bch2_get_key_or_hole(iter, POS_MAX, hole);
if (bkey_err(k))
return k;
if (!k.k->type) {
struct bpos bucket = bkey_start_pos(k.k);
if (!bch2_dev_bucket_exists(c, bucket)) {
if (!next_bucket(c, &bucket))
return bkey_s_c_null;
bch2_btree_iter_set_pos(iter, bucket);
goto again;
}
if (!bch2_dev_bucket_exists(c, k.k->p)) {
struct bch_dev *ca = bch_dev_bkey_exists(c, bucket.inode);
bch2_key_resize(hole, ca->mi.nbuckets - bucket.offset);
}
}
return k;
}
static int bch2_check_alloc_key(struct btree_trans *trans,
struct bkey_s_c alloc_k,
struct btree_iter *alloc_iter,
struct btree_iter *discard_iter,
struct btree_iter *freespace_iter)
@ -745,20 +844,10 @@ static int bch2_check_alloc_key(struct btree_trans *trans,
struct bch_alloc_v4 a_convert;
const struct bch_alloc_v4 *a;
unsigned discard_key_type, freespace_key_type;
struct bkey_s_c alloc_k, k;
struct bkey_s_c k;
struct printbuf buf = PRINTBUF;
int ret;
alloc_k = bch2_dev_bucket_exists(c, alloc_iter->pos)
? bch2_btree_iter_peek_slot(alloc_iter)
: bch2_btree_iter_peek(alloc_iter);
if (!alloc_k.k)
return 1;
ret = bkey_err(alloc_k);
if (ret)
return ret;
if (fsck_err_on(!bch2_dev_bucket_exists(c, alloc_k.k->p), c,
"alloc key for invalid device:bucket %llu:%llu",
alloc_k.k->p.inode, alloc_k.k->p.offset))
@ -841,6 +930,61 @@ static int bch2_check_alloc_key(struct btree_trans *trans,
return ret;
}
static int bch2_check_alloc_hole(struct btree_trans *trans,
struct bpos start,
struct bpos *end,
struct btree_iter *freespace_iter)
{
struct bch_fs *c = trans->c;
struct bch_dev *ca;
struct bkey_s_c k;
struct printbuf buf = PRINTBUF;
int ret;
ca = bch_dev_bkey_exists(c, start.inode);
if (!ca->mi.freespace_initialized)
return 0;
bch2_btree_iter_set_pos(freespace_iter, start);
k = bch2_btree_iter_peek_slot(freespace_iter);
ret = bkey_err(k);
if (ret)
goto err;
*end = bkey_min(k.k->p, *end);
if (k.k->type != KEY_TYPE_set &&
(c->opts.reconstruct_alloc ||
fsck_err(c, "hole in alloc btree missing in freespace btree\n"
" device %llu buckets %llu-%llu",
freespace_iter->pos.inode,
freespace_iter->pos.offset,
end->offset))) {
struct bkey_i *update =
bch2_trans_kmalloc(trans, sizeof(*update));
ret = PTR_ERR_OR_ZERO(update);
if (ret)
goto err;
bkey_init(&update->k);
update->k.type = KEY_TYPE_set;
update->k.p = freespace_iter->pos;
bch2_key_resize(&update->k,
min_t(u64, U32_MAX, end->offset -
freespace_iter->pos.offset));
ret = bch2_trans_update(trans, freespace_iter, update, 0);
if (ret)
goto err;
}
err:
fsck_err:
printbuf_exit(&buf);
return ret;
}
static int bch2_check_discard_freespace_key(struct btree_trans *trans,
struct btree_iter *iter)
{
@ -900,6 +1044,7 @@ int bch2_check_alloc_info(struct bch_fs *c)
{
struct btree_trans trans;
struct btree_iter iter, discard_iter, freespace_iter;
struct bkey hole;
struct bkey_s_c k;
int ret = 0;
@ -911,17 +1056,52 @@ int bch2_check_alloc_info(struct bch_fs *c)
BTREE_ITER_PREFETCH);
bch2_trans_iter_init(&trans, &freespace_iter, BTREE_ID_freespace, POS_MIN,
BTREE_ITER_PREFETCH);
while (1) {
ret = commit_do(&trans, NULL, NULL,
BTREE_INSERT_NOFAIL|
BTREE_INSERT_LAZY_RW,
bch2_check_alloc_key(&trans, &iter,
&discard_iter,
&freespace_iter));
struct bpos next;
bch2_trans_begin(&trans);
k = bch2_get_key_or_real_bucket_hole(&iter, &hole);
ret = bkey_err(k);
if (ret)
goto bkey_err;
if (!k.k)
break;
bch2_btree_iter_advance(&iter);
if (k.k->type) {
next = bpos_nosnap_successor(k.k->p);
ret = bch2_check_alloc_key(&trans,
k, &iter,
&discard_iter,
&freespace_iter);
if (ret)
break;
} else {
next = k.k->p;
ret = bch2_check_alloc_hole(&trans,
bkey_start_pos(k.k),
&next,
&freespace_iter);
if (ret)
goto bkey_err;
}
ret = bch2_trans_commit(&trans, NULL, NULL,
BTREE_INSERT_NOFAIL|
BTREE_INSERT_LAZY_RW);
if (ret)
goto bkey_err;
bch2_btree_iter_set_pos(&iter, next);
bkey_err:
if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
continue;
if (ret)
break;
}
bch2_trans_iter_exit(&trans, &freespace_iter);
bch2_trans_iter_exit(&trans, &discard_iter);
@ -1322,6 +1502,7 @@ static int bch2_dev_freespace_init(struct bch_fs *c, struct bch_dev *ca)
struct btree_trans trans;
struct btree_iter iter;
struct bkey_s_c k;
struct bkey hole;
struct bpos end = POS(ca->dev_idx, ca->mi.nbuckets);
struct bch_member *m;
int ret;
@ -1337,12 +1518,13 @@ static int bch2_dev_freespace_init(struct bch_fs *c, struct bch_dev *ca)
*/
while (1) {
bch2_trans_begin(&trans);
ret = 0;
if (bkey_ge(iter.pos, end))
if (bkey_ge(iter.pos, end)) {
ret = 0;
break;
}
k = bch2_btree_iter_peek_slot(&iter);
k = bch2_get_key_or_hole(&iter, end, &hole);
ret = bkey_err(k);
if (ret)
goto bkey_err;
@ -1364,34 +1546,7 @@ static int bch2_dev_freespace_init(struct bch_fs *c, struct bch_dev *ca)
bch2_btree_iter_advance(&iter);
} else {
/*
* When there's a hole, process a whole range of keys
* all at once:
*
* This is similar to how extent btree iterators in
* slots mode will synthesize a whole range - a
* KEY_TYPE_deleted extent.
*
* But alloc keys aren't extents (they have zero size),
* so we're open coding it here:
*/
struct btree_iter iter2;
struct bkey_i *freespace;
struct bpos next;
bch2_trans_copy_iter(&iter2, &iter);
k = bch2_btree_iter_peek_upto(&iter2,
bkey_min(bkey_min(end,
iter.path->l[0].b->key.k.p),
POS(iter.pos.inode, iter.pos.offset + U32_MAX - 1)));
next = iter2.pos;
ret = bkey_err(k);
bch2_trans_iter_exit(&trans, &iter2);
BUG_ON(next.offset >= iter.pos.offset + U32_MAX);
if (ret)
goto bkey_err;
freespace = bch2_trans_kmalloc(&trans, sizeof(*freespace));
ret = PTR_ERR_OR_ZERO(freespace);
@ -1399,10 +1554,9 @@ static int bch2_dev_freespace_init(struct bch_fs *c, struct bch_dev *ca)
goto bkey_err;
bkey_init(&freespace->k);
freespace->k.type = KEY_TYPE_set;
freespace->k.p = iter.pos;
bch2_key_resize(&freespace->k, next.offset - iter.pos.offset);
freespace->k.type = KEY_TYPE_set;
freespace->k.p = k.k->p;
freespace->k.size = k.k->size;
ret = __bch2_btree_insert(&trans, BTREE_ID_freespace, freespace) ?:
bch2_trans_commit(&trans, NULL, NULL,
@ -1411,7 +1565,7 @@ static int bch2_dev_freespace_init(struct bch_fs *c, struct bch_dev *ca)
if (ret)
goto bkey_err;
bch2_btree_iter_set_pos(&iter, next);
bch2_btree_iter_set_pos(&iter, k.k->p);
}
bkey_err:
if (bch2_err_matches(ret, BCH_ERR_transaction_restart))