bcachefs: Add error messages for memory allocation failures

This adds some missing diagnostics from rare but annoying to debug
runtime allocation failure paths.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

fs/bcachefs/btree_key_cache.c

@@ -147,19 +147,23 @@ bkey_cached_reuse(struct btree_key_cache *c)
 }
 
 static struct bkey_cached *
-btree_key_cache_create(struct btree_key_cache *c,
+btree_key_cache_create(struct bch_fs *c,
 		       enum btree_id btree_id,
 		       struct bpos pos)
 {
+	struct btree_key_cache *bc = &c->btree_key_cache;
 	struct bkey_cached *ck;
 	bool was_new = true;
 
-	ck = bkey_cached_alloc(c);
+	ck = bkey_cached_alloc(bc);
 
 	if (unlikely(!ck)) {
-		ck = bkey_cached_reuse(c);
-		if (unlikely(!ck))
+		ck = bkey_cached_reuse(bc);
+		if (unlikely(!ck)) {
+			bch_err(c, "error allocating memory for key cache item, btree %s",
+				bch2_btree_ids[btree_id]);
 			return ERR_PTR(-ENOMEM);
+		}
 
 		was_new = false;
 	}
@@ -176,7 +180,7 @@ btree_key_cache_create(struct btree_key_cache *c,
 	ck->valid		= false;
 	ck->flags		= 1U << BKEY_CACHED_ACCESSED;
 
-	if (unlikely(rhashtable_lookup_insert_fast(&c->table,
+	if (unlikely(rhashtable_lookup_insert_fast(&bc->table,
 					  &ck->hash,
 					  bch2_btree_key_cache_params))) {
 		/* We raced with another fill: */
@@ -186,15 +190,15 @@ btree_key_cache_create(struct btree_key_cache *c,
 			six_unlock_intent(&ck->c.lock);
 			kfree(ck);
 		} else {
-			mutex_lock(&c->lock);
-			bkey_cached_free(c, ck);
-			mutex_unlock(&c->lock);
+			mutex_lock(&bc->lock);
+			bkey_cached_free(bc, ck);
+			mutex_unlock(&bc->lock);
 		}
 
 		return NULL;
 	}
 
-	atomic_long_inc(&c->nr_keys);
+	atomic_long_inc(&bc->nr_keys);
 
 	six_unlock_write(&ck->c.lock);
 
@@ -205,6 +209,7 @@ static int btree_key_cache_fill(struct btree_trans *trans,
 				struct btree_path *ck_path,
 				struct bkey_cached *ck)
 {
+	struct bch_fs *c = trans->c;
 	struct btree_iter iter;
 	struct bkey_s_c k;
 	unsigned new_u64s = 0;
@@ -234,6 +239,8 @@ static int btree_key_cache_fill(struct btree_trans *trans,
 		new_u64s = roundup_pow_of_two(new_u64s);
 		new_k = kmalloc(new_u64s * sizeof(u64), GFP_NOFS);
 		if (!new_k) {
+			bch_err(c, "error allocating memory for key cache key, btree %s u64s %u",
+				bch2_btree_ids[ck->key.btree_id], new_u64s);
 			ret = -ENOMEM;
 			goto err;
 		}
@@ -294,8 +301,7 @@ int bch2_btree_path_traverse_cached(struct btree_trans *trans, struct btree_path
 			return 0;
 		}
 
-		ck = btree_key_cache_create(&c->btree_key_cache,
-					    path->btree_id, path->pos);
+		ck = btree_key_cache_create(c, path->btree_id, path->pos);
 		ret = PTR_ERR_OR_ZERO(ck);
 		if (ret)
 			goto err;

fs/bcachefs/btree_update_leaf.c

@@ -308,6 +308,7 @@ btree_key_can_insert_cached(struct btree_trans *trans,
 			    struct btree_path *path,
 			    unsigned u64s)
 {
+	struct bch_fs *c = trans->c;
 	struct bkey_cached *ck = (void *) path->l[0].b;
 	unsigned new_u64s;
 	struct bkey_i *new_k;
@@ -315,7 +316,7 @@ btree_key_can_insert_cached(struct btree_trans *trans,
 	EBUG_ON(path->level);
 
 	if (!test_bit(BKEY_CACHED_DIRTY, &ck->flags) &&
-	    bch2_btree_key_cache_must_wait(trans->c) &&
+	    bch2_btree_key_cache_must_wait(c) &&
 	    !(trans->flags & BTREE_INSERT_JOURNAL_RECLAIM))
 		return BTREE_INSERT_NEED_JOURNAL_RECLAIM;
 
@@ -330,8 +331,11 @@ btree_key_can_insert_cached(struct btree_trans *trans,
 
 	new_u64s	= roundup_pow_of_two(u64s);
 	new_k		= krealloc(ck->k, new_u64s * sizeof(u64), GFP_NOFS);
-	if (!new_k)
+	if (!new_k) {
+		bch_err(c, "error allocating memory for key cache key, btree %s u64s %u",
+			bch2_btree_ids[path->btree_id], new_u64s);
 		return -ENOMEM;
+	}
 
 	ck->u64s	= new_u64s;
 	ck->k		= new_k;

fs/bcachefs/buckets.c

@@ -926,9 +926,11 @@ static int bch2_mark_stripe_ptr(struct btree_trans *trans,
 	BUG_ON(!(flags & BTREE_TRIGGER_GC));
 
 	m = genradix_ptr_alloc(&c->gc_stripes, p.idx, GFP_KERNEL);
-
-	if (!m)
+	if (!m) {
+		bch_err(c, "error allocating memory for gc_stripes, idx %llu",
+			(u64) p.idx);
 		return -ENOMEM;
+	}
 
 	spin_lock(&c->ec_stripes_heap_lock);
 
@@ -1039,7 +1041,7 @@ static int bch2_mark_stripe(struct btree_trans *trans,
 	bool gc = flags & BTREE_TRIGGER_GC;
 	u64 journal_seq = trans->journal_res.seq;
 	struct bch_fs *c = trans->c;
-	size_t idx = new.k->p.offset;
+	u64 idx = new.k->p.offset;
 	const struct bch_stripe *old_s = old.k->type == KEY_TYPE_stripe
 		? bkey_s_c_to_stripe(old).v : NULL;
 	const struct bch_stripe *new_s = new.k->type == KEY_TYPE_stripe
@@ -1057,7 +1059,7 @@ static int bch2_mark_stripe(struct btree_trans *trans,
 
 			bch2_bkey_val_to_text(&PBUF(buf1), c, old);
 			bch2_bkey_val_to_text(&PBUF(buf2), c, new);
-			bch_err_ratelimited(c, "error marking nonexistent stripe %zu while marking\n"
+			bch_err_ratelimited(c, "error marking nonexistent stripe %llu while marking\n"
 					    "old %s\n"
 					    "new %s", idx, buf1, buf2);
 			bch2_inconsistent_error(c);
@@ -1089,9 +1091,11 @@ static int bch2_mark_stripe(struct btree_trans *trans,
 		struct gc_stripe *m =
 			genradix_ptr_alloc(&c->gc_stripes, idx, GFP_KERNEL);
 
-		if (!m)
+		if (!m) {
+			bch_err(c, "error allocating memory for gc_stripes, idx %llu",
+				idx);
 			return -ENOMEM;
-
+		}
 		/*
 		 * This will be wrong when we bring back runtime gc: we should
 		 * be unmarking the old key and then marking the new key

fs/bcachefs/fsck.c

@@ -564,14 +564,17 @@ static struct inode_walker inode_walker_init(void)
 	return (struct inode_walker) { 0, };
 }
 
-static int inode_walker_realloc(struct inode_walker *w)
+static int inode_walker_realloc(struct bch_fs *c, struct inode_walker *w)
 {
 	if (w->nr == w->size) {
 		size_t new_size = max_t(size_t, 8UL, w->size * 2);
 		void *d = krealloc(w->d, new_size * sizeof(w->d[0]),
 				   GFP_KERNEL);
-		if (!d)
+		if (!d) {
+			bch_err(c, "fsck: error allocating memory for inode_walker, size %zu",
+				new_size);
 			return -ENOMEM;
+		}
 
 		w->d = d;
 		w->size = new_size;
@@ -586,7 +589,7 @@ static int add_inode(struct bch_fs *c, struct inode_walker *w,
 	struct bch_inode_unpacked u;
 	int ret;
 
-	ret = inode_walker_realloc(w);
+	ret = inode_walker_realloc(c, w);
 	if (ret)
 		return ret;
 
@@ -647,7 +650,7 @@ static int __walk_inode(struct btree_trans *trans,
 		while (i && w->d[i - 1].snapshot > pos.snapshot)
 			--i;
 
-		ret = inode_walker_realloc(w);
+		ret = inode_walker_realloc(c, w);
 		if (ret)
 			return ret;
 
@@ -1812,7 +1815,8 @@ static bool path_is_dup(struct pathbuf *p, u64 inum, u32 snapshot)
 	return false;
 }
 
-static int path_down(struct pathbuf *p, u64 inum, u32 snapshot)
+static int path_down(struct bch_fs *c, struct pathbuf *p,
+		     u64 inum, u32 snapshot)
 {
 	if (p->nr == p->size) {
 		size_t new_size = max_t(size_t, 256UL, p->size * 2);
@@ -1820,6 +1824,8 @@ static int path_down(struct pathbuf *p, u64 inum, u32 snapshot)
 				   new_size * sizeof(p->entries[0]),
 				   GFP_KERNEL);
 		if (!n) {
+			bch_err(c, "fsck: error allocating memory for pathbuf, size %zu",
+				new_size);
 			return -ENOMEM;
 		}
 
@@ -1893,7 +1899,7 @@ static int check_path(struct btree_trans *trans,
 		if (!S_ISDIR(inode->bi_mode))
 			break;
 
-		ret = path_down(p, inode->bi_inum, snapshot);
+		ret = path_down(c, p, inode->bi_inum, snapshot);
 		if (ret) {
 			bch_err(c, "memory allocation failure");
 			return ret;
@@ -1998,12 +2004,15 @@ struct nlink_table {
 	}		*d;
 };
 
-static int add_nlink(struct nlink_table *t, u64 inum, u32 snapshot)
+static int add_nlink(struct bch_fs *c, struct nlink_table *t,
+		     u64 inum, u32 snapshot)
 {
 	if (t->nr == t->size) {
 		size_t new_size = max_t(size_t, 128UL, t->size * 2);
 		void *d = kvmalloc(new_size * sizeof(t->d[0]), GFP_KERNEL);
 		if (!d) {
+			bch_err(c, "fsck: error allocating memory for nlink_table, size %zu",
+				new_size);
 			return -ENOMEM;
 		}
 
@@ -2093,7 +2102,7 @@ static int check_nlinks_find_hardlinks(struct bch_fs *c,
 		if (!u.bi_nlink)
 			continue;
 
-		ret = add_nlink(t, k.k->p.offset, k.k->p.snapshot);
+		ret = add_nlink(c, t, k.k->p.offset, k.k->p.snapshot);
 		if (ret) {
 			*end = k.k->p.offset;
 			ret = 0;