Commit 2452cc89 authored by Slava Pestov's avatar Slava Pestov Committed by Kent Overstreet
Browse files

bcache: try to set b->parent properly 

bcache_flash_dev.ktest would reliably crash with 8k and 16k bucket size
before; now it passes.

Change-Id: Ib542232235e39298c3a7548fe52b645cabb823d1
parent c9a78332

drivers/md/bcache/btree.c

+21 −16
Original line number Diff line number Diff line
@@ -117,9 +117,9 @@ 
({									\

	int _r, l = (b)->level - 1;					\

	bool _w = l <= (op)->lock;					\

	struct btree *_child = bch_btree_node_get((b)->c, op, key, l, _w);\

	struct btree *_child = bch_btree_node_get((b)->c, op, key, l,	\

						  _w, b);		\

	if (!IS_ERR(_child)) {						\

		_child->parent = (b);					\

		_r = bch_btree_ ## fn(_child, op, ##__VA_ARGS__);	\

		rw_unlock(_w, _child);					\

	} else								\
@@ -142,7 +142,6 @@ 
		rw_lock(_w, _b, _b->level);				\

		if (_b == (c)->root &&					\

		    _w == insert_lock(op, _b)) {			\

			_b->parent = NULL;				\

			_r = bch_btree_ ## fn(_b, op, ##__VA_ARGS__);	\

		}							\

		rw_unlock(_w, _b);					\
@@ -967,7 +966,8 @@ static struct btree *mca_alloc(struct cache_set *c, struct btree_op *op, 
 * level and op->lock.

 */

struct btree *bch_btree_node_get(struct cache_set *c, struct btree_op *op,

				 struct bkey *k, int level, bool write)

				 struct bkey *k, int level, bool write,

				 struct btree *parent)

{

	int i = 0;

	struct btree *b;
@@ -1002,6 +1002,7 @@ struct btree *bch_btree_node_get(struct cache_set *c, struct btree_op *op, 
		BUG_ON(b->level != level);

	}



	b->parent = parent;

	b->accessed = 1;



	for (; i <= b->keys.nsets && b->keys.set[i].size; i++) {
@@ -1022,15 +1023,16 @@ struct btree *bch_btree_node_get(struct cache_set *c, struct btree_op *op, 
	return b;

}



static void btree_node_prefetch(struct cache_set *c, struct bkey *k, int level)

static void btree_node_prefetch(struct btree *parent, struct bkey *k)

{

	struct btree *b;



	mutex_lock(&c->bucket_lock);

	b = mca_alloc(c, NULL, k, level);

	mutex_unlock(&c->bucket_lock);

	mutex_lock(&parent->c->bucket_lock);

	b = mca_alloc(parent->c, NULL, k, parent->level - 1);

	mutex_unlock(&parent->c->bucket_lock);



	if (!IS_ERR_OR_NULL(b)) {

		b->parent = parent;

		bch_btree_node_read(b);

		rw_unlock(true, b);

	}
@@ -1061,7 +1063,8 @@ static void btree_node_free(struct btree *b) 
}



struct btree *__bch_btree_node_alloc(struct cache_set *c, struct btree_op *op,

				     int level, bool wait)

				     int level, bool wait,

				     struct btree *parent)

{

	BKEY_PADDED(key) k;

	struct btree *b = ERR_PTR(-EAGAIN);
@@ -1085,6 +1088,7 @@ struct btree *__bch_btree_node_alloc(struct cache_set *c, struct btree_op *op, 
	}



	b->accessed = 1;

	b->parent = parent;

	bch_bset_init_next(&b->keys, b->keys.set->data, bset_magic(&b->c->sb));



	mutex_unlock(&c->bucket_lock);
@@ -1101,15 +1105,16 @@ struct btree *__bch_btree_node_alloc(struct cache_set *c, struct btree_op *op, 
}



static struct btree *bch_btree_node_alloc(struct cache_set *c,

					  struct btree_op *op, int level)

					  struct btree_op *op, int level,

					  struct btree *parent)

{

	return __bch_btree_node_alloc(c, op, level, op != NULL);

	return __bch_btree_node_alloc(c, op, level, op != NULL, parent);

}



static struct btree *btree_node_alloc_replacement(struct btree *b,

						  struct btree_op *op)

{

	struct btree *n = bch_btree_node_alloc(b->c, op, b->level);

	struct btree *n = bch_btree_node_alloc(b->c, op, b->level, b->parent);

	if (!IS_ERR_OR_NULL(n)) {

		mutex_lock(&n->write_lock);

		bch_btree_sort_into(&b->keys, &n->keys, &b->c->sort);
@@ -1523,7 +1528,7 @@ static int btree_gc_recurse(struct btree *b, struct btree_op *op, 
		k = bch_btree_iter_next_filter(&iter, &b->keys, bch_ptr_bad);

		if (k) {

			r->b = bch_btree_node_get(b->c, op, k, b->level - 1,

						  true);

						  true, b);

			if (IS_ERR(r->b)) {

				ret = PTR_ERR(r->b);

				break;
@@ -1818,7 +1823,7 @@ static int bch_btree_check_recurse(struct btree *b, struct btree_op *op) 
			k = bch_btree_iter_next_filter(&iter, &b->keys,

						       bch_ptr_bad);

			if (k)

				btree_node_prefetch(b->c, k, b->level - 1);

				btree_node_prefetch(b, k);



			if (p)

				ret = btree(check_recurse, p, b, op);
@@ -1983,12 +1988,12 @@ static int btree_split(struct btree *b, struct btree_op *op, 


		trace_bcache_btree_node_split(b, btree_bset_first(n1)->keys);



		n2 = bch_btree_node_alloc(b->c, op, b->level);

		n2 = bch_btree_node_alloc(b->c, op, b->level, b->parent);

		if (IS_ERR(n2))

			goto err_free1;



		if (!b->parent) {

			n3 = bch_btree_node_alloc(b->c, op, b->level + 1);

			n3 = bch_btree_node_alloc(b->c, op, b->level + 1, NULL);

			if (IS_ERR(n3))

				goto err_free2;

		}

drivers/md/bcache/btree.h

+2 −2
Original line number Diff line number Diff line
@@ -243,9 +243,9 @@ void bch_btree_node_write(struct btree *, struct closure *); 


void bch_btree_set_root(struct btree *);

struct btree *__bch_btree_node_alloc(struct cache_set *, struct btree_op *,

				     int, bool);

				     int, bool, struct btree *);

struct btree *bch_btree_node_get(struct cache_set *, struct btree_op *,

				 struct bkey *, int, bool);

				 struct bkey *, int, bool, struct btree *);



int bch_btree_insert_check_key(struct btree *, struct btree_op *,

			       struct bkey *);

drivers/md/bcache/super.c

+2 −2
Original line number Diff line number Diff line
@@ -1601,7 +1601,7 @@ static void run_cache_set(struct cache_set *c) 
			goto err;



		err = "error reading btree root";

		c->root = bch_btree_node_get(c, NULL, k, j->btree_level, true);

		c->root = bch_btree_node_get(c, NULL, k, j->btree_level, true, NULL);

		if (IS_ERR_OR_NULL(c->root))

			goto err;
@@ -1676,7 +1676,7 @@ static void run_cache_set(struct cache_set *c) 
			goto err;



		err = "cannot allocate new btree root";

		c->root = __bch_btree_node_alloc(c, NULL, 0, true);

		c->root = __bch_btree_node_alloc(c, NULL, 0, true, NULL);

		if (IS_ERR_OR_NULL(c->root))

			goto err;