bcache: Make bch_keylist_realloc() take u64s, not nptrs

Getting away from KEY_PTRS and moving toward KEY_U64s - and getting rid of magic
2s

Also - split out the part that checks against journal entry size so as to avoid
a dependancy on struct cache_set in bset.c

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
diff --git a/drivers/md/bcache/bset.c b/drivers/md/bcache/bset.c
index e688265..f91347a 100644
--- a/drivers/md/bcache/bset.c
+++ b/drivers/md/bcache/bset.c
@@ -14,21 +14,13 @@
 
 /* Keylists */
 
-int bch_keylist_realloc(struct keylist *l, int nptrs, struct cache_set *c)
+int __bch_keylist_realloc(struct keylist *l, unsigned u64s)
 {
 	size_t oldsize = bch_keylist_nkeys(l);
-	size_t newsize = oldsize + 2 + nptrs;
+	size_t newsize = oldsize + u64s;
 	uint64_t *old_keys = l->keys_p == l->inline_keys ? NULL : l->keys_p;
 	uint64_t *new_keys;
 
-	/* The journalling code doesn't handle the case where the keys to insert
-	 * is bigger than an empty write: If we just return -ENOMEM here,
-	 * bio_insert() and bio_invalidate() will insert the keys created so far
-	 * and finish the rest when the keylist is empty.
-	 */
-	if (newsize * sizeof(uint64_t) > block_bytes(c) - sizeof(struct jset))
-		return -ENOMEM;
-
 	newsize = roundup_pow_of_two(newsize);
 
 	if (newsize <= KEYLIST_INLINE ||
diff --git a/drivers/md/bcache/bset.h b/drivers/md/bcache/bset.h
index ba02f05..303d31a 100644
--- a/drivers/md/bcache/bset.h
+++ b/drivers/md/bcache/bset.h
@@ -259,7 +259,7 @@
 
 struct bkey *bch_keylist_pop(struct keylist *);
 void bch_keylist_pop_front(struct keylist *);
-int bch_keylist_realloc(struct keylist *, int, struct cache_set *);
+int __bch_keylist_realloc(struct keylist *, unsigned);
 
 void bch_bkey_copy_single_ptr(struct bkey *, const struct bkey *,
 			      unsigned);
diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c
index f035ae3..f0a6399 100644
--- a/drivers/md/bcache/btree.c
+++ b/drivers/md/bcache/btree.c
@@ -1356,8 +1356,8 @@
 
 		n2->keys -= keys;
 
-		if (bch_keylist_realloc(keylist,
-					KEY_PTRS(&new_nodes[i]->key), b->c))
+		if (__bch_keylist_realloc(keylist,
+					  bkey_u64s(&new_nodes[i]->key)))
 			goto out_nocoalesce;
 
 		bch_btree_node_write(new_nodes[i], &cl);
@@ -1365,7 +1365,7 @@
 	}
 
 	for (i = 0; i < nodes; i++) {
-		if (bch_keylist_realloc(keylist, KEY_PTRS(&r[i].b->key), b->c))
+		if (__bch_keylist_realloc(keylist, bkey_u64s(&r[i].b->key)))
 			goto out_nocoalesce;
 
 		make_btree_freeing_key(r[i].b, keylist->top);
diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index cce02f1..fcdb59f 100644
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -255,6 +255,24 @@
 	closure_return(cl);
 }
 
+static int bch_keylist_realloc(struct keylist *l, unsigned u64s,
+			       struct cache_set *c)
+{
+	size_t oldsize = bch_keylist_nkeys(l);
+	size_t newsize = oldsize + u64s;
+
+	/*
+	 * The journalling code doesn't handle the case where the keys to insert
+	 * is bigger than an empty write: If we just return -ENOMEM here,
+	 * bio_insert() and bio_invalidate() will insert the keys created so far
+	 * and finish the rest when the keylist is empty.
+	 */
+	if (newsize * sizeof(uint64_t) > block_bytes(c) - sizeof(struct jset))
+		return -ENOMEM;
+
+	return __bch_keylist_realloc(l, u64s);
+}
+
 static void bch_data_invalidate(struct closure *cl)
 {
 	struct data_insert_op *op = container_of(cl, struct data_insert_op, cl);
@@ -267,7 +285,7 @@
 		unsigned sectors = min(bio_sectors(bio),
 				       1U << (KEY_SIZE_BITS - 1));
 
-		if (bch_keylist_realloc(&op->insert_keys, 0, op->c))
+		if (bch_keylist_realloc(&op->insert_keys, 2, op->c))
 			goto out;
 
 		bio->bi_iter.bi_sector	+= sectors;
@@ -357,7 +375,7 @@
 
 		/* 1 for the device pointer and 1 for the chksum */
 		if (bch_keylist_realloc(&op->insert_keys,
-					1 + (op->csum ? 1 : 0),
+					3 + (op->csum ? 1 : 0),
 					op->c))
 			continue_at(cl, bch_data_insert_keys, bcache_wq);