bcachefs: More errcode cleanup

We shouldn't be overloading standard error codes now that we have
provisions for bcachefs-specific errorcodes: this patch converts super.c
and super-io.c to per error site errcodes, with a bit of cleanup.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

19 files changed, 211 insertions, 183 deletions

diff --git a/fs/bcachefs/alloc_background.c b/fs/bcachefs/alloc_background.c
index a0b9fa30260a..cef5de13a6e4 100644
--- a/fs/bcachefs/alloc_background.c
+++ b/fs/bcachefs/alloc_background.c
@@ -302,7 +302,7 @@ int bch2_alloc_v1_invalid(const struct bch_fs *c, struct bkey_s_c k,
 	if (bkey_val_u64s(a.k) < bch_alloc_v1_val_u64s(a.v)) {
 		prt_printf(err, "incorrect value size (%zu < %u)",
 		       bkey_val_u64s(a.k), bch_alloc_v1_val_u64s(a.v));
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	return 0;
@@ -315,7 +315,7 @@ int bch2_alloc_v2_invalid(const struct bch_fs *c, struct bkey_s_c k,
 
 	if (bch2_alloc_unpack_v2(&u, k)) {
 		prt_printf(err, "unpack error");
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	return 0;
@@ -328,7 +328,7 @@ int bch2_alloc_v3_invalid(const struct bch_fs *c, struct bkey_s_c k,
 
 	if (bch2_alloc_unpack_v3(&u, k)) {
 		prt_printf(err, "unpack error");
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	return 0;
@@ -342,14 +342,14 @@ int bch2_alloc_v4_invalid(const struct bch_fs *c, struct bkey_s_c k,
 	if (bkey_val_bytes(k.k) != sizeof(struct bch_alloc_v4)) {
 		prt_printf(err, "bad val size (%zu != %zu)",
 		       bkey_val_bytes(k.k), sizeof(struct bch_alloc_v4));
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (rw == WRITE) {
 		if (alloc_data_type(*a.v, a.v->data_type) != a.v->data_type) {
 			prt_printf(err, "invalid data type (got %u should be %u)",
 			       a.v->data_type, alloc_data_type(*a.v, a.v->data_type));
-			return -EINVAL;
+			return -BCH_ERR_invalid_bkey;
 		}
 
 		switch (a.v->data_type) {
@@ -360,7 +360,7 @@ int bch2_alloc_v4_invalid(const struct bch_fs *c, struct bkey_s_c k,
 			    a.v->cached_sectors ||
 			    a.v->stripe) {
 				prt_printf(err, "empty data type free but have data");
-				return -EINVAL;
+				return -BCH_ERR_invalid_bkey;
 			}
 			break;
 		case BCH_DATA_sb:
@@ -371,7 +371,7 @@ int bch2_alloc_v4_invalid(const struct bch_fs *c, struct bkey_s_c k,
 			if (!a.v->dirty_sectors) {
 				prt_printf(err, "data_type %s but dirty_sectors==0",
 				       bch2_data_types[a.v->data_type]);
-				return -EINVAL;
+				return -BCH_ERR_invalid_bkey;
 			}
 			break;
 		case BCH_DATA_cached:
@@ -379,20 +379,20 @@ int bch2_alloc_v4_invalid(const struct bch_fs *c, struct bkey_s_c k,
 			    a.v->dirty_sectors ||
 			    a.v->stripe) {
 				prt_printf(err, "data type inconsistency");
-				return -EINVAL;
+				return -BCH_ERR_invalid_bkey;
 			}
 
 			if (!a.v->io_time[READ] &&
 			    test_bit(BCH_FS_CHECK_ALLOC_TO_LRU_REFS_DONE, &c->flags)) {
 				prt_printf(err, "cached bucket with read_time == 0");
-				return -EINVAL;
+				return -BCH_ERR_invalid_bkey;
 			}
 			break;
 		case BCH_DATA_stripe:
 			if (!a.v->stripe) {
 				prt_printf(err, "data_type %s but stripe==0",
 				       bch2_data_types[a.v->data_type]);
-				return -EINVAL;
+				return -BCH_ERR_invalid_bkey;
 			}
 			break;
 		}
diff --git a/fs/bcachefs/bkey_methods.c b/fs/bcachefs/bkey_methods.c
index 7fcd6ca40b93..29809da5e9cf 100644
--- a/fs/bcachefs/bkey_methods.c
+++ b/fs/bcachefs/bkey_methods.c
@@ -42,7 +42,7 @@ static int empty_val_key_invalid(const struct bch_fs *c, struct bkey_s_c k,
 	if (bkey_val_bytes(k.k)) {
 		prt_printf(err, "incorrect value size (%zu != 0)",
 		       bkey_val_bytes(k.k));
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	return 0;
@@ -58,7 +58,7 @@ static int key_type_cookie_invalid(const struct bch_fs *c, struct bkey_s_c k,
 	if (bkey_val_bytes(k.k) != sizeof(struct bch_cookie)) {
 		prt_printf(err, "incorrect value size (%zu != %zu)",
 		       bkey_val_bytes(k.k), sizeof(struct bch_cookie));
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	return 0;
@@ -99,7 +99,7 @@ static int key_type_set_invalid(const struct bch_fs *c, struct bkey_s_c k,
 	if (bkey_val_bytes(k.k)) {
 		prt_printf(err, "incorrect value size (%zu != %zu)",
 		       bkey_val_bytes(k.k), sizeof(struct bch_cookie));
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	return 0;
@@ -127,7 +127,7 @@ int bch2_bkey_val_invalid(struct bch_fs *c, struct bkey_s_c k,
 {
 	if (k.k->type >= KEY_TYPE_MAX) {
 		prt_printf(err, "invalid type (%u >= %u)", k.k->type, KEY_TYPE_MAX);
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	return bch2_bkey_ops[k.k->type].key_invalid(c, k, rw, err);
@@ -203,30 +203,30 @@ int __bch2_bkey_invalid(struct bch_fs *c, struct bkey_s_c k,
 {
 	if (k.k->u64s < BKEY_U64s) {
 		prt_printf(err, "u64s too small (%u < %zu)", k.k->u64s, BKEY_U64s);
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (!(bch2_key_types_allowed[type] & (1U << k.k->type))) {
 		prt_printf(err, "invalid key type for btree %s (%s)",
 			   bch2_btree_ids[type], bch2_bkey_types[k.k->type]);
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (btree_node_type_is_extents(type) && !bkey_whiteout(k.k)) {
 		if (k.k->size == 0) {
 			prt_printf(err, "size == 0");
-			return -EINVAL;
+			return -BCH_ERR_invalid_bkey;
 		}
 
 		if (k.k->size > k.k->p.offset) {
 			prt_printf(err, "size greater than offset (%u > %llu)",
 			       k.k->size, k.k->p.offset);
-			return -EINVAL;
+			return -BCH_ERR_invalid_bkey;
 		}
 	} else {
 		if (k.k->size) {
 			prt_printf(err, "size != 0");
-			return -EINVAL;
+			return -BCH_ERR_invalid_bkey;
 		}
 	}
 
@@ -234,20 +234,20 @@ int __bch2_bkey_invalid(struct bch_fs *c, struct bkey_s_c k,
 	    !btree_type_has_snapshots(type) &&
 	    k.k->p.snapshot) {
 		prt_printf(err, "nonzero snapshot");
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (type != BKEY_TYPE_btree &&
 	    btree_type_has_snapshots(type) &&
 	    !k.k->p.snapshot) {
 		prt_printf(err, "snapshot == 0");
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (type != BKEY_TYPE_btree &&
 	    bkey_eq(k.k->p, POS_MAX)) {
 		prt_printf(err, "key at POS_MAX");
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	return 0;
@@ -266,12 +266,12 @@ int bch2_bkey_in_btree_node(struct btree *b, struct bkey_s_c k,
 {
 	if (bpos_lt(k.k->p, b->data->min_key)) {
 		prt_printf(err, "key before start of btree node");
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (bpos_gt(k.k->p, b->data->max_key)) {
 		prt_printf(err, "key past end of btree node");
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	return 0;
diff --git a/fs/bcachefs/dirent.c b/fs/bcachefs/dirent.c
index c2126f39369b..f1838b7c45ee 100644
--- a/fs/bcachefs/dirent.c
+++ b/fs/bcachefs/dirent.c
@@ -92,46 +92,46 @@ int bch2_dirent_invalid(const struct bch_fs *c, struct bkey_s_c k,
 	if (bkey_val_bytes(k.k) < sizeof(struct bch_dirent)) {
 		prt_printf(err, "incorrect value size (%zu < %zu)",
 		       bkey_val_bytes(k.k), sizeof(*d.v));
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	len = bch2_dirent_name_bytes(d);
 	if (!len) {
 		prt_printf(err, "empty name");
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (bkey_val_u64s(k.k) > dirent_val_u64s(len)) {
 		prt_printf(err, "value too big (%zu > %u)",
 		       bkey_val_u64s(k.k), dirent_val_u64s(len));
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (len > BCH_NAME_MAX) {
 		prt_printf(err, "dirent name too big (%u > %u)",
 		       len, BCH_NAME_MAX);
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (len == 1 && !memcmp(d.v->d_name, ".", 1)) {
 		prt_printf(err, "invalid name");
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (len == 2 && !memcmp(d.v->d_name, "..", 2)) {
 		prt_printf(err, "invalid name");
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (memchr(d.v->d_name, '/', len)) {
 		prt_printf(err, "invalid name");
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (d.v->d_type != DT_SUBVOL &&
 	    le64_to_cpu(d.v->d_inum) == d.k->p.inode) {
 		prt_printf(err, "dirent points to own directory");
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	return 0;
diff --git a/fs/bcachefs/disk_groups.c b/fs/bcachefs/disk_groups.c
index 6b81f35861ac..fcd5dbff248d 100644
--- a/fs/bcachefs/disk_groups.c
+++ b/fs/bcachefs/disk_groups.c
@@ -27,7 +27,7 @@ static int bch2_sb_disk_groups_validate(struct bch_sb *sb,
 	struct bch_sb_field_members *mi = bch2_sb_get_members(sb);
 	unsigned nr_groups = disk_groups_nr(groups);
 	unsigned i, len;
-	int ret = -EINVAL;
+	int ret = 0;
 
 	for (i = 0; i < sb->nr_devices; i++) {
 		struct bch_member *m = mi->members + i;
@@ -41,12 +41,12 @@ static int bch2_sb_disk_groups_validate(struct bch_sb *sb,
 		if (g >= nr_groups) {
 			prt_printf(err, "disk %u has invalid label %u (have %u)",
 			       i, g, nr_groups);
-			return -EINVAL;
+			return -BCH_ERR_invalid_sb_disk_groups;
 		}
 
 		if (BCH_GROUP_DELETED(&groups->entries[g])) {
 			prt_printf(err, "disk %u has deleted label %u", i, g);
-			return -EINVAL;
+			return -BCH_ERR_invalid_sb_disk_groups;
 		}
 	}
 
@@ -62,7 +62,7 @@ static int bch2_sb_disk_groups_validate(struct bch_sb *sb,
 		len = strnlen(g->label, sizeof(g->label));
 		if (!len) {
 			prt_printf(err, "label %u empty", i);
-			return -EINVAL;
+			return -BCH_ERR_invalid_sb_disk_groups;
 		}
 	}
 
@@ -79,13 +79,12 @@ static int bch2_sb_disk_groups_validate(struct bch_sb *sb,
 			prt_printf(err, "duplicate label %llu.%.*s",
 			       BCH_GROUP_PARENT(g),
 			       (int) sizeof(g->label), g->label);
+			ret = -BCH_ERR_invalid_sb_disk_groups;
 			goto err;
 		}
-
-	ret = 0;
 err:
 	kfree(sorted);
-	return 0;
+	return ret;
 }
 
 static void bch2_sb_disk_groups_to_text(struct printbuf *out,
diff --git a/fs/bcachefs/ec.c b/fs/bcachefs/ec.c
index 503a47b39ad1..c855ea025f0e 100644
--- a/fs/bcachefs/ec.c
+++ b/fs/bcachefs/ec.c
@@ -109,24 +109,24 @@ int bch2_stripe_invalid(const struct bch_fs *c, struct bkey_s_c k,
 
 	if (bkey_eq(k.k->p, POS_MIN)) {
 		prt_printf(err, "stripe at POS_MIN");
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (k.k->p.inode) {
 		prt_printf(err, "nonzero inode field");
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (bkey_val_bytes(k.k) < sizeof(*s)) {
 		prt_printf(err, "incorrect value size (%zu < %zu)",
 		       bkey_val_bytes(k.k), sizeof(*s));
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (bkey_val_u64s(k.k) < stripe_val_u64s(s)) {
 		prt_printf(err, "incorrect value size (%zu < %u)",
 		       bkey_val_u64s(k.k), stripe_val_u64s(s));
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	return bch2_bkey_ptrs_invalid(c, k, rw, err);
diff --git a/fs/bcachefs/errcode.h b/fs/bcachefs/errcode.h
index 3ec5808dcbd9..dc388864be6f 100644
--- a/fs/bcachefs/errcode.h
+++ b/fs/bcachefs/errcode.h
@@ -67,7 +67,45 @@
 	x(BCH_ERR_fsck,			fsck_repair_unimplemented)		\
 	x(BCH_ERR_fsck,			fsck_repair_impossible)			\
 	x(0,				need_snapshot_cleanup)			\
-	x(0,				need_topology_repair)
+	x(0,				need_topology_repair)			\
+	x(EINVAL,			device_state_not_allowed)		\
+	x(EINVAL,			member_info_missing)			\
+	x(EINVAL,			mismatched_block_size)			\
+	x(EINVAL,			block_size_too_small)			\
+	x(EINVAL,			bucket_size_too_small)			\
+	x(EINVAL,			device_size_too_small)			\
+	x(EINVAL,			device_not_a_member_of_filesystem)	\
+	x(EINVAL,			device_has_been_removed)		\
+	x(EINVAL,			device_already_online)			\
+	x(EINVAL,			insufficient_devices_to_start)		\
+	x(EINVAL,			invalid)				\
+	x(BCH_ERR_invalid,		invalid_sb)				\
+	x(BCH_ERR_invalid_sb,		invalid_sb_magic)			\
+	x(BCH_ERR_invalid_sb,		invalid_sb_version)			\
+	x(BCH_ERR_invalid_sb,		invalid_sb_features)			\
+	x(BCH_ERR_invalid_sb,		invalid_sb_too_big)			\
+	x(BCH_ERR_invalid_sb,		invalid_sb_csum_type)			\
+	x(BCH_ERR_invalid_sb,		invalid_sb_csum)			\
+	x(BCH_ERR_invalid_sb,		invalid_sb_block_size)			\
+	x(BCH_ERR_invalid_sb,		invalid_sb_uuid)			\
+	x(BCH_ERR_invalid_sb,		invalid_sb_too_many_members)		\
+	x(BCH_ERR_invalid_sb,		invalid_sb_dev_idx)			\
+	x(BCH_ERR_invalid_sb,		invalid_sb_time_precision)		\
+	x(BCH_ERR_invalid_sb,		invalid_sb_field_size)			\
+	x(BCH_ERR_invalid_sb,		invalid_sb_layout)			\
+	x(BCH_ERR_invalid_sb_layout,	invalid_sb_layout_type)			\
+	x(BCH_ERR_invalid_sb_layout,	invalid_sb_layout_nr_superblocks)	\
+	x(BCH_ERR_invalid_sb_layout,	invalid_sb_layout_superblocks_overlap)	\
+	x(BCH_ERR_invalid_sb,		invalid_sb_members_missing)		\
+	x(BCH_ERR_invalid_sb,		invalid_sb_members)			\
+	x(BCH_ERR_invalid_sb,		invalid_sb_disk_groups)			\
+	x(BCH_ERR_invalid_sb,		invalid_sb_replicas)			\
+	x(BCH_ERR_invalid_sb,		invalid_sb_journal)			\
+	x(BCH_ERR_invalid_sb,		invalid_sb_journal_seq_blacklist)	\
+	x(BCH_ERR_invalid_sb,		invalid_sb_crypt)			\
+	x(BCH_ERR_invalid_sb,		invalid_sb_clean)			\
+	x(BCH_ERR_invalid_sb,		invalid_sb_quota)			\
+	x(BCH_ERR_invalid,		invalid_bkey)				\
 
 enum bch_errcode {
 	BCH_ERR_START		= 2048,
diff --git a/fs/bcachefs/extents.c b/fs/bcachefs/extents.c
index e3bc39bee197..422adca7230b 100644
--- a/fs/bcachefs/extents.c
+++ b/fs/bcachefs/extents.c
@@ -163,7 +163,7 @@ int bch2_btree_ptr_invalid(const struct bch_fs *c, struct bkey_s_c k,
 	if (bkey_val_u64s(k.k) > BCH_REPLICAS_MAX) {
 		prt_printf(err, "value too big (%zu > %u)",
 		       bkey_val_u64s(k.k), BCH_REPLICAS_MAX);
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	return bch2_bkey_ptrs_invalid(c, k, rw, err);
@@ -183,20 +183,20 @@ int bch2_btree_ptr_v2_invalid(const struct bch_fs *c, struct bkey_s_c k,
 	if (bkey_val_bytes(k.k) <= sizeof(*bp.v)) {
 		prt_printf(err, "value too small (%zu <= %zu)",
 		       bkey_val_bytes(k.k), sizeof(*bp.v));
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (bkey_val_u64s(k.k) > BKEY_BTREE_PTR_VAL_U64s_MAX) {
 		prt_printf(err, "value too big (%zu > %zu)",
 		       bkey_val_u64s(k.k), BKEY_BTREE_PTR_VAL_U64s_MAX);
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (c->sb.version < bcachefs_metadata_version_snapshot &&
 	    bp.v->min_key.snapshot) {
 		prt_printf(err, "invalid min_key.snapshot (%u != 0)",
 		       bp.v->min_key.snapshot);
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	return bch2_bkey_ptrs_invalid(c, k, rw, err);
@@ -387,13 +387,13 @@ int bch2_reservation_invalid(const struct bch_fs *c, struct bkey_s_c k,
 	if (bkey_val_bytes(k.k) != sizeof(struct bch_reservation)) {
 		prt_printf(err, "incorrect value size (%zu != %zu)",
 		       bkey_val_bytes(k.k), sizeof(*r.v));
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (!r.v->nr_replicas || r.v->nr_replicas > BCH_REPLICAS_MAX) {
 		prt_printf(err, "invalid nr_replicas (%u)",
 		       r.v->nr_replicas);
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	return 0;
@@ -1054,14 +1054,14 @@ static int extent_ptr_invalid(const struct bch_fs *c,
 
 	if (!bch2_dev_exists2(c, ptr->dev)) {
 		prt_printf(err, "pointer to invalid device (%u)", ptr->dev);
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	ca = bch_dev_bkey_exists(c, ptr->dev);
 	bkey_for_each_ptr(ptrs, ptr2)
 		if (ptr != ptr2 && ptr->dev == ptr2->dev) {
 			prt_printf(err, "multiple pointers to same device (%u)", ptr->dev);
-			return -EINVAL;
+			return -BCH_ERR_invalid_bkey;
 		}
 
 	bucket = sector_to_bucket_and_offset(ca, ptr->offset, &bucket_offset);
@@ -1069,19 +1069,19 @@ static int extent_ptr_invalid(const struct bch_fs *c,
 	if (bucket >= ca->mi.nbuckets) {
 		prt_printf(err, "pointer past last bucket (%llu > %llu)",
 		       bucket, ca->mi.nbuckets);
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (ptr->offset < bucket_to_sector(ca, ca->mi.first_bucket)) {
 		prt_printf(err, "pointer before first bucket (%llu < %u)",
 		       bucket, ca->mi.first_bucket);
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (bucket_offset + size_ondisk > ca->mi.bucket_size) {
 		prt_printf(err, "pointer spans multiple buckets (%u + %u > %u)",
 		       bucket_offset, size_ondisk, ca->mi.bucket_size);
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	return 0;
@@ -1105,13 +1105,13 @@ int bch2_bkey_ptrs_invalid(const struct bch_fs *c, struct bkey_s_c k,
 		if (__extent_entry_type(entry) >= BCH_EXTENT_ENTRY_MAX) {
 			prt_printf(err, "invalid extent entry type (got %u, max %u)",
 			       __extent_entry_type(entry), BCH_EXTENT_ENTRY_MAX);
-			return -EINVAL;
+			return -BCH_ERR_invalid_bkey;
 		}
 
 		if (bkey_is_btree_ptr(k.k) &&
 		    !extent_entry_is_ptr(entry)) {
 			prt_printf(err, "has non ptr field");
-			return -EINVAL;
+			return -BCH_ERR_invalid_bkey;
 		}
 
 		switch (extent_entry_type(entry)) {
@@ -1130,19 +1130,19 @@ int bch2_bkey_ptrs_invalid(const struct bch_fs *c, struct bkey_s_c k,
 			if (crc.offset + crc.live_size >
 			    crc.uncompressed_size) {
 				prt_printf(err, "checksum offset + key size > uncompressed size");
-				return -EINVAL;
+				return -BCH_ERR_invalid_bkey;
 			}
 
 			size_ondisk = crc.compressed_size;
 
 			if (!bch2_checksum_type_valid(c, crc.csum_type)) {
 				prt_printf(err, "invalid checksum type");
-				return -EINVAL;
+				return -BCH_ERR_invalid_bkey;
 			}
 
 			if (crc.compression_type >= BCH_COMPRESSION_TYPE_NR) {
 				prt_printf(err, "invalid compression type");
-				return -EINVAL;
+				return -BCH_ERR_invalid_bkey;
 			}
 
 			if (bch2_csum_type_is_encryption(crc.csum_type)) {
@@ -1150,7 +1150,7 @@ int bch2_bkey_ptrs_invalid(const struct bch_fs *c, struct bkey_s_c k,
 					nonce = crc.offset + crc.nonce;
 				else if (nonce != crc.offset + crc.nonce) {
 					prt_printf(err, "incorrect nonce");
-					return -EINVAL;
+					return -BCH_ERR_invalid_bkey;
 				}
 			}
 			break;
@@ -1161,7 +1161,7 @@ int bch2_bkey_ptrs_invalid(const struct bch_fs *c, struct bkey_s_c k,
 
 	if (nr_ptrs >= BCH_BKEY_PTRS_MAX) {
 		prt_str(err, "too many ptrs");
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	return 0;
diff --git a/fs/bcachefs/fs.c b/fs/bcachefs/fs.c
index 90297cfc7934..cc41472a335e 100644
--- a/fs/bcachefs/fs.c
+++ b/fs/bcachefs/fs.c
@@ -1767,8 +1767,11 @@ got_sb:
 	kfree(devs[0]);
 	kfree(devs);
 
-	if (IS_ERR(sb))
-		return ERR_CAST(sb);
+	if (IS_ERR(sb)) {
+		ret = PTR_ERR(sb);
+		ret = bch2_err_class(ret);
+		return ERR_PTR(ret);
+	}
 
 	c = sb->s_fs_info;
 
diff --git a/fs/bcachefs/inode.c b/fs/bcachefs/inode.c
index 4ca70c6c3a4f..cf453edcb5ab 100644
--- a/fs/bcachefs/inode.c
+++ b/fs/bcachefs/inode.c
@@ -306,40 +306,40 @@ static int __bch2_inode_invalid(struct bkey_s_c k, struct printbuf *err)
 
 	if (k.k->p.inode) {
 		prt_printf(err, "nonzero k.p.inode");
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (k.k->p.offset < BLOCKDEV_INODE_MAX) {
 		prt_printf(err, "fs inode in blockdev range");
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (bch2_inode_unpack(k, &unpacked)) {
 		prt_printf(err, "invalid variable length fields");
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (unpacked.bi_data_checksum >= BCH_CSUM_OPT_NR + 1) {
 		prt_printf(err, "invalid data checksum type (%u >= %u",
 			unpacked.bi_data_checksum, BCH_CSUM_OPT_NR + 1);
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (unpacked.bi_compression >= BCH_COMPRESSION_OPT_NR + 1) {
 		prt_printf(err, "invalid data checksum type (%u >= %u)",
 		       unpacked.bi_compression, BCH_COMPRESSION_OPT_NR + 1);
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if ((unpacked.bi_flags & BCH_INODE_UNLINKED) &&
 	    unpacked.bi_nlink != 0) {
 		prt_printf(err, "flagged as unlinked but bi_nlink != 0");
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (unpacked.bi_subvol && !S_ISDIR(unpacked.bi_mode)) {
 		prt_printf(err, "subvolume root but not a directory");
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	return 0;
@@ -353,13 +353,13 @@ int bch2_inode_invalid(const struct bch_fs *c, struct bkey_s_c k,
 	if (bkey_val_bytes(k.k) < sizeof(*inode.v)) {
 		prt_printf(err, "incorrect value size (%zu < %zu)",
 		       bkey_val_bytes(k.k), sizeof(*inode.v));
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (INODE_STR_HASH(inode.v) >= BCH_STR_HASH_NR) {
 		prt_printf(err, "invalid str hash type (%llu >= %u)",
 		       INODE_STR_HASH(inode.v), BCH_STR_HASH_NR);
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	return __bch2_inode_invalid(k, err);
@@ -373,13 +373,13 @@ int bch2_inode_v2_invalid(const struct bch_fs *c, struct bkey_s_c k,
 	if (bkey_val_bytes(k.k) < sizeof(*inode.v)) {
 		prt_printf(err, "incorrect value size (%zu < %zu)",
 		       bkey_val_bytes(k.k), sizeof(*inode.v));
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (INODEv2_STR_HASH(inode.v) >= BCH_STR_HASH_NR) {
 		prt_printf(err, "invalid str hash type (%llu >= %u)",
 		       INODEv2_STR_HASH(inode.v), BCH_STR_HASH_NR);
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	return __bch2_inode_invalid(k, err);
@@ -421,13 +421,13 @@ int bch2_inode_generation_invalid(const struct bch_fs *c, struct bkey_s_c k,
 {
 	if (k.k->p.inode) {
 		prt_printf(err, "nonzero k.p.inode");
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (bkey_val_bytes(k.k) != sizeof(struct bch_inode_generation)) {
 		prt_printf(err, "incorrect value size (%zu != %zu)",
 		       bkey_val_bytes(k.k), sizeof(struct bch_inode_generation));
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	return 0;
diff --git a/fs/bcachefs/journal_sb.c b/fs/bcachefs/journal_sb.c
index c19db0425dd7..9b933330a4c3 100644
--- a/fs/bcachefs/journal_sb.c
+++ b/fs/bcachefs/journal_sb.c
@@ -22,7 +22,7 @@ static int bch2_sb_journal_validate(struct bch_sb *sb,
 {
 	struct bch_sb_field_journal *journal = field_to_type(f, journal);
 	struct bch_member *m = bch2_sb_get_members(sb)->members + sb->dev_idx;
-	int ret = -EINVAL;
+	int ret = -BCH_ERR_invalid_sb_journal;
 	unsigned nr;
 	unsigned i;
 	u64 *b;
@@ -105,7 +105,7 @@ static int bch2_sb_journal_v2_validate(struct bch_sb *sb,
 {
 	struct bch_sb_field_journal_v2 *journal = field_to_type(f, journal_v2);
 	struct bch_member *m = bch2_sb_get_members(sb)->members + sb->dev_idx;
-	int ret = -EINVAL;
+	int ret = -BCH_ERR_invalid_sb_journal;
 	unsigned nr;
 	unsigned i;
 	struct u64_range *b;
diff --git a/fs/bcachefs/journal_seq_blacklist.c b/fs/bcachefs/journal_seq_blacklist.c
index 5c555b3703c0..012c870acce0 100644
--- a/fs/bcachefs/journal_seq_blacklist.c
+++ b/fs/bcachefs/journal_seq_blacklist.c
@@ -203,7 +203,7 @@ static int bch2_sb_journal_seq_blacklist_validate(struct bch_sb *sb,
 		    le64_to_cpu(e->end)) {
 			prt_printf(err, "entry %u start >= end (%llu >= %llu)",
 			       i, le64_to_cpu(e->start), le64_to_cpu(e->end));
-			return -EINVAL;
+			return -BCH_ERR_invalid_sb_journal_seq_blacklist;
 		}
 
 		if (i + 1 < nr &&
@@ -211,7 +211,7 @@ static int bch2_sb_journal_seq_blacklist_validate(struct bch_sb *sb,
 		    le64_to_cpu(e[1].start)) {
 			prt_printf(err, "entry %u out of order with next entry (%llu > %llu)",
 			       i + 1, le64_to_cpu(e[0].end), le64_to_cpu(e[1].start));
-			return -EINVAL;
+			return -BCH_ERR_invalid_sb_journal_seq_blacklist;
 		}
 	}
 
diff --git a/fs/bcachefs/lru.c b/fs/bcachefs/lru.c
index 53e607d72274..db1674ef1d22 100644
--- a/fs/bcachefs/lru.c
+++ b/fs/bcachefs/lru.c
@@ -16,7 +16,7 @@ int bch2_lru_invalid(const struct bch_fs *c, struct bkey_s_c k,
 	if (bkey_val_bytes(k.k) < sizeof(*lru)) {
 		prt_printf(err, "incorrect value size (%zu < %zu)",
 		       bkey_val_bytes(k.k), sizeof(*lru));
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	return 0;
diff --git a/fs/bcachefs/quota.c b/fs/bcachefs/quota.c
index 7f74c026e9da..ededc826e9a0 100644
--- a/fs/bcachefs/quota.c
+++ b/fs/bcachefs/quota.c
@@ -26,7 +26,7 @@ static int bch2_sb_quota_validate(struct bch_sb *sb, struct bch_sb_field *f,
 	if (vstruct_bytes(&q->field) < sizeof(*q)) {
 		prt_printf(err, "wrong size (got %zu should be %zu)",
 		       vstruct_bytes(&q->field), sizeof(*q));
-		return -EINVAL;
+		return -BCH_ERR_invalid_sb_quota;
 	}
 
 	return 0;
@@ -64,13 +64,13 @@ int bch2_quota_invalid(const struct bch_fs *c, struct bkey_s_c k,
 	if (k.k->p.inode >= QTYP_NR) {
 		prt_printf(err, "invalid quota type (%llu >= %u)",
 		       k.k->p.inode, QTYP_NR);
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (bkey_val_bytes(k.k) != sizeof(struct bch_quota)) {
 		prt_printf(err, "incorrect value size (%zu != %zu)",
 		       bkey_val_bytes(k.k), sizeof(struct bch_quota));
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	return 0;
diff --git a/fs/bcachefs/reflink.c b/fs/bcachefs/reflink.c
index aebed671c43a..8c426d6440c9 100644
--- a/fs/bcachefs/reflink.c
+++ b/fs/bcachefs/reflink.c
@@ -85,7 +85,7 @@ int bch2_reflink_v_invalid(const struct bch_fs *c, struct bkey_s_c k,
 	if (bkey_val_bytes(r.k) < sizeof(*r.v)) {
 		prt_printf(err, "incorrect value size (%zu < %zu)",
 		       bkey_val_bytes(r.k), sizeof(*r.v));
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	return bch2_bkey_ptrs_invalid(c, k, rw, err);
@@ -136,7 +136,7 @@ int bch2_indirect_inline_data_invalid(const struct bch_fs *c, struct bkey_s_c k,
 	if (bkey_val_bytes(k.k) < sizeof(struct bch_indirect_inline_data)) {
 		prt_printf(err, "incorrect value size (%zu < %zu)",
 		       bkey_val_bytes(k.k), sizeof(struct bch_indirect_inline_data));
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	return 0;
diff --git a/fs/bcachefs/replicas.c b/fs/bcachefs/replicas.c
index e540c1aa91ba..482bedf4be8b 100644
--- a/fs/bcachefs/replicas.c
+++ b/fs/bcachefs/replicas.c
@@ -841,27 +841,27 @@ static int bch2_cpu_replicas_validate(struct bch_replicas_cpu *cpu_r,
 		if (e->data_type >= BCH_DATA_NR) {
 			prt_printf(err, "invalid data type in entry ");
 			bch2_replicas_entry_to_text(err, e);
-			return -EINVAL;
+			return -BCH_ERR_invalid_sb_replicas;
 		}
 
 		if (!e->nr_devs) {
 			prt_printf(err, "no devices in entry ");
 			bch2_replicas_entry_to_text(err, e);
-			return -EINVAL;
+			return -BCH_ERR_invalid_sb_replicas;
 		}
 
 		if (e->nr_required > 1 &&
 		    e->nr_required >= e->nr_devs) {
 			prt_printf(err, "bad nr_required in entry ");
 			bch2_replicas_entry_to_text(err, e);
-			return -EINVAL;
+			return -BCH_ERR_invalid_sb_replicas;
 		}
 
 		for (j = 0; j < e->nr_devs; j++)
 			if (!bch2_dev_exists(sb, mi, e->devs[j])) {
 				prt_printf(err, "invalid device %u in entry ", e->devs[j]);
 				bch2_replicas_entry_to_text(err, e);
-				return -EINVAL;
+				return -BCH_ERR_invalid_sb_replicas;
 			}
 
 		if (i + 1 < cpu_r->nr) {
@@ -873,7 +873,7 @@ static int bch2_cpu_replicas_validate(struct bch_replicas_cpu *cpu_r,
 			if (!memcmp(e, n, cpu_r->entry_size)) {
 				prt_printf(err, "duplicate replicas entry ");
 				bch2_replicas_entry_to_text(err, e);
-				return -EINVAL;
+				return -BCH_ERR_invalid_sb_replicas;
 			}
 		}
 	}
diff --git a/fs/bcachefs/subvolume.c b/fs/bcachefs/subvolume.c
index e37ffaad5883..f19f6f8d3233 100644
--- a/fs/bcachefs/subvolume.c
+++ b/fs/bcachefs/subvolume.c
@@ -33,13 +33,13 @@ int bch2_snapshot_invalid(const struct bch_fs *c, struct bkey_s_c k,
 	if (bkey_gt(k.k->p, POS(0, U32_MAX)) ||
 	    bkey_lt(k.k->p, POS(0, 1))) {
 		prt_printf(err, "bad pos");
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (bkey_val_bytes(k.k) != sizeof(struct bch_snapshot)) {
 		prt_printf(err, "bad val size (%zu != %zu)",
 		       bkey_val_bytes(k.k), sizeof(struct bch_snapshot));
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	s = bkey_s_c_to_snapshot(k);
@@ -48,18 +48,18 @@ int bch2_snapshot_invalid(const struct bch_fs *c, struct bkey_s_c k,
 	if (id && id <= k.k->p.offset) {
 		prt_printf(err, "bad parent node (%u <= %llu)",
 		       id, k.k->p.offset);
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (le32_to_cpu(s.v->children[0]) < le32_to_cpu(s.v->children[1])) {
 		prt_printf(err, "children not normalized");
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (s.v->children[0] &&
 	    s.v->children[0] == s.v->children[1]) {
 		prt_printf(err, "duplicate child nodes");
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	for (i = 0; i < 2; i++) {
@@ -68,7 +68,7 @@ int bch2_snapshot_invalid(const struct bch_fs *c, struct bkey_s_c k,
 		if (id >= k.k->p.offset) {
 			prt_printf(err, "bad child node (%u >= %llu)",
 			       id, k.k->p.offset);
-			return -EINVAL;
+			return -BCH_ERR_invalid_bkey;
 		}
 	}
 
@@ -773,13 +773,13 @@ int bch2_subvolume_invalid(const struct bch_fs *c, struct bkey_s_c k,
 	if (bkey_lt(k.k->p, SUBVOL_POS_MIN) ||
 	    bkey_gt(k.k->p, SUBVOL_POS_MAX)) {
 		prt_printf(err, "invalid pos");
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (bkey_val_bytes(k.k) != sizeof(struct bch_subvolume)) {
 		prt_printf(err, "incorrect value size (%zu != %zu)",
 		       bkey_val_bytes(k.k), sizeof(struct bch_subvolume));
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	return 0;
diff --git a/fs/bcachefs/super-io.c b/fs/bcachefs/super-io.c
index e27b301432b1..8dfe92d7eb77 100644
--- a/fs/bcachefs/super-io.c
+++ b/fs/bcachefs/super-io.c
@@ -216,23 +216,23 @@ static int validate_sb_layout(struct bch_sb_layout *layout, struct printbuf *out
 	if (!uuid_equal(&layout->magic, &BCACHE_MAGIC) &&
 	    !uuid_equal(&layout->magic, &BCHFS_MAGIC)) {
 		prt_printf(out, "Not a bcachefs superblock layout");
-		return -EINVAL;
+		return -BCH_ERR_invalid_sb_layout;
 	}
 
 	if (layout->layout_type != 0) {
 		prt_printf(out, "Invalid superblock layout type %u",
 		       layout->layout_type);
-		return -EINVAL;
+		return -BCH_ERR_invalid_sb_layout_type;
 	}
 
 	if (!layout->nr_superblocks) {
 		prt_printf(out, "Invalid superblock layout: no superblocks");
-		return -EINVAL;
+		return -BCH_ERR_invalid_sb_layout_nr_superblocks;
 	}
 
 	if (layout->nr_superblocks > ARRAY_SIZE(layout->sb_offset)) {
 		prt_printf(out, "Invalid superblock layout: too many superblocks");
-		return -EINVAL;
+		return -BCH_ERR_invalid_sb_layout_nr_superblocks;
 	}
 
 	max_sectors = 1 << layout->sb_max_size_bits;
@@ -246,7 +246,7 @@ static int validate_sb_layout(struct bch_sb_layout *layout, struct printbuf *out
 			prt_printf(out, "Invalid superblock layout: superblocks overlap\n"
 			       "  (sb %u ends at %llu next starts at %llu",
 			       i - 1, prev_offset + max_sectors, offset);
-			return -EINVAL;
+			return -BCH_ERR_invalid_sb_layout_superblocks_overlap;
 		}
 		prev_offset = offset;
 	}
@@ -273,25 +273,25 @@ static int bch2_sb_validate(struct bch_sb_handle *disk_sb, struct printbuf *out,
 	if (version    >= bcachefs_metadata_version_max) {
 		prt_printf(out, "Unsupported superblock version %u (min %u, max %u)",
 		       version, bcachefs_metadata_version_min, bcachefs_metadata_version_max);
-		return -EINVAL;
+		return -BCH_ERR_invalid_sb_version;
 	}
 
 	if (version_min < bcachefs_metadata_version_min) {
 		prt_printf(out, "Unsupported superblock version %u (min %u, max %u)",
 		       version_min, bcachefs_metadata_version_min, bcachefs_metadata_version_max);
-		return -EINVAL;
+		return -BCH_ERR_invalid_sb_version;
 	}
 
 	if (version_min > version) {
 		prt_printf(out, "Bad minimum version %u, greater than version field %u",
 		       version_min, version);
-		return -EINVAL;
+		return -BCH_ERR_invalid_sb_version;
 	}
 
 	if (sb->features[1] ||
 	    (le64_to_cpu(sb->features[0]) & (~0ULL << BCH_FEATURE_NR))) {
 		prt_printf(out, "Filesystem has incompatible features");
-		return -EINVAL;
+		return -BCH_ERR_invalid_sb_features;
 	}
 
 	block_size = le16_to_cpu(sb->block_size);
@@ -299,37 +299,37 @@ static int bch2_sb_validate(struct bch_sb_handle *disk_sb, struct printbuf *out,
 	if (block_size > PAGE_SECTORS) {
 		prt_printf(out, "Block size too big (got %u, max %u)",
 		       block_size, PAGE_SECTORS);
-		return -EINVAL;
+		return -BCH_ERR_invalid_sb_block_size;
 	}
 
 	if (bch2_is_zero(sb->user_uuid.b, sizeof(sb->user_uuid))) {
 		prt_printf(out, "Bad user UUID (got zeroes)");
-		return -EINVAL;
+		return -BCH_ERR_invalid_sb_uuid;
 	}
 
 	if (bch2_is_zero(sb->uuid.b, sizeof(sb->uuid))) {
 		prt_printf(out, "Bad intenal UUID (got zeroes)");
-		return -EINVAL;
+		return -BCH_ERR_invalid_sb_uuid;
 	}
 
 	if (!sb->nr_devices ||
 	    sb->nr_devices > BCH_SB_MEMBERS_MAX) {
 		prt_printf(out, "Bad number of member devices %u (max %u)",
 		       sb->nr_devices, BCH_SB_MEMBERS_MAX);
-		return -EINVAL;
+		return -BCH_ERR_invalid_sb_too_many_members;
 	}
 
 	if (sb->dev_idx >= sb->nr_devices) {
 		prt_printf(out, "Bad dev_idx (got %u, nr_devices %u)",
 		       sb->dev_idx, sb->nr_devices);
-		return -EINVAL;
+		return -BCH_ERR_invalid_sb_dev_idx;
 	}
 
 	if (!sb->time_precision ||
 	    le32_to_cpu(sb->time_precision) > NSEC_PER_SEC) {
 		prt_printf(out, "Invalid time precision: %u (min 1, max %lu)",
 		       le32_to_cpu(sb->time_precision), NSEC_PER_SEC);
-		return -EINVAL;
+		return -BCH_ERR_invalid_sb_time_precision;
 	}
 
 	if (rw == READ) {
@@ -366,15 +366,15 @@ static int bch2_sb_validate(struct bch_sb_handle *disk_sb, struct printbuf *out,
 
 	vstruct_for_each(sb, f) {
 		if (!f->u64s) {
-			prt_printf(out, "Invalid superblock: optional with size 0 (type %u)",
+			prt_printf(out, "Invalid superblock: optional field with size 0 (type %u)",
 			       le32_to_cpu(f->type));
-			return -EINVAL;
+			return -BCH_ERR_invalid_sb_field_size;
 		}
 
 		if (vstruct_next(f) > vstruct_last(sb)) {
 			prt_printf(out, "Invalid superblock: optional field extends past end of superblock (type %u)",
 			       le32_to_cpu(f->type));
-			return -EINVAL;
+			return -BCH_ERR_invalid_sb_field_size;
 		}
 	}
 
@@ -382,7 +382,7 @@ static int bch2_sb_validate(struct bch_sb_handle *disk_sb, struct printbuf *out,
 	mi = bch2_sb_get_members(sb);
 	if (!mi) {
 		prt_printf(out, "Invalid superblock: member info area missing");
-		return -EINVAL;
+		return -BCH_ERR_invalid_sb_members_missing;
 	}
 
 	ret = bch2_sb_field_validate(sb, &mi->field, out);
@@ -544,7 +544,7 @@ reread:
 	if (!uuid_equal(&sb->sb->magic, &BCACHE_MAGIC) &&
 	    !uuid_equal(&sb->sb->magic, &BCHFS_MAGIC)) {
 		prt_printf(err, "Not a bcachefs superblock");
-		return -EINVAL;
+		return -BCH_ERR_invalid_sb_magic;
 	}
 
 	version		= le16_to_cpu(sb->sb->version);
@@ -555,13 +555,13 @@ reread:
 	if (version    >= bcachefs_metadata_version_max) {
 		prt_printf(err, "Unsupported superblock version %u (min %u, max %u)",
 		       version, bcachefs_metadata_version_min, bcachefs_metadata_version_max);
-		return -EINVAL;
+		return -BCH_ERR_invalid_sb_version;
 	}
 
 	if (version_min < bcachefs_metadata_version_min) {
 		prt_printf(err, "Unsupported superblock version %u (min %u, max %u)",
 		       version_min, bcachefs_metadata_version_min, bcachefs_metadata_version_max);
-		return -EINVAL;
+		return -BCH_ERR_invalid_sb_version;
 	}
 
 	bytes = vstruct_bytes(sb->sb);
@@ -569,7 +569,7 @@ reread:
 	if (bytes > 512 << sb->sb->layout.sb_max_size_bits) {
 		prt_printf(err, "Invalid superblock: too big (got %zu bytes, layout max %lu)",
 		       bytes, 512UL << sb->sb->layout.sb_max_size_bits);
-		return -EINVAL;
+		return -BCH_ERR_invalid_sb_too_big;
 	}
 
 	if (bytes > sb->buffer_size) {
@@ -580,7 +580,7 @@ reread:
 
 	if (BCH_SB_CSUM_TYPE(sb->sb) >= BCH_CSUM_NR) {
 		prt_printf(err, "unknown checksum type %llu", BCH_SB_CSUM_TYPE(sb->sb));
-		return -EINVAL;
+		return -BCH_ERR_invalid_sb_csum_type;
 	}
 
 	/* XXX: verify MACs */
@@ -589,7 +589,7 @@ reread:
 
 	if (bch2_crc_cmp(csum, sb->sb->csum)) {
 		prt_printf(err, "bad checksum");
-		return -EINVAL;
+		return -BCH_ERR_invalid_sb_csum;
 	}
 
 	sb->seq = le64_to_cpu(sb->sb->seq);
@@ -703,7 +703,7 @@ got_super:
 		prt_printf(&err, "block size (%u) smaller than device block size (%u)",
 		       le16_to_cpu(sb->sb->block_size) << 9,
 		       bdev_logical_block_size(sb->bdev));
-		ret = -EINVAL;
+		ret = -BCH_ERR_block_size_too_small;
 		goto err;
 	}
 
@@ -958,7 +958,7 @@ static int bch2_sb_members_validate(struct bch_sb *sb,
 	if ((void *) (mi->members + sb->nr_devices) >
 	    vstruct_end(&mi->field)) {
 		prt_printf(err, "too many devices for section size");
-		return -EINVAL;
+		return -BCH_ERR_invalid_sb_members;
 	}
 
 	for (i = 0; i < sb->nr_devices; i++) {
@@ -970,28 +970,28 @@ static int bch2_sb_members_validate(struct bch_sb *sb,
 		if (le64_to_cpu(m->nbuckets) > LONG_MAX) {
 			prt_printf(err, "device %u: too many buckets (got %llu, max %lu)",
 			       i, le64_to_cpu(m->nbuckets), LONG_MAX);
-			return -EINVAL;
+			return -BCH_ERR_invalid_sb_members;
 		}
 
 		if (le64_to_cpu(m->nbuckets) -
 		    le16_to_cpu(m->first_bucket) < BCH_MIN_NR_NBUCKETS) {
 			prt_printf(err, "device %u: not enough buckets (got %llu, max %u)",
 			       i, le64_to_cpu(m->nbuckets), BCH_MIN_NR_NBUCKETS);
-			return -EINVAL;
+			return -BCH_ERR_invalid_sb_members;
 		}
 
 		if (le16_to_cpu(m->bucket_size) <
 		    le16_to_cpu(sb->block_size)) {
 			prt_printf(err, "device %u: bucket size %u smaller than block size %u",
 			       i, le16_to_cpu(m->bucket_size), le16_to_cpu(sb->block_size));
-			return -EINVAL;
+			return -BCH_ERR_invalid_sb_members;
 		}
 
 		if (le16_to_cpu(m->bucket_size) <
 		    BCH_SB_BTREE_NODE_SIZE(sb)) {
 			prt_printf(err, "device %u: bucket size %u smaller than btree node size %llu",
 			       i, le16_to_cpu(m->bucket_size), BCH_SB_BTREE_NODE_SIZE(sb));
-			return -EINVAL;
+			return -BCH_ERR_invalid_sb_members;
 		}
 	}
 
@@ -1123,12 +1123,12 @@ static int bch2_sb_crypt_validate(struct bch_sb *sb,
 	if (vstruct_bytes(&crypt->field) < sizeof(*crypt)) {
 		prt_printf(err, "wrong size (got %zu should be %zu)",
 		       vstruct_bytes(&crypt->field), sizeof(*crypt));
-		return -EINVAL;
+		return -BCH_ERR_invalid_sb_crypt;
 	}
 
 	if (BCH_CRYPT_KDF_TYPE(crypt)) {
 		prt_printf(err, "bad kdf type %llu", BCH_CRYPT_KDF_TYPE(crypt));
-		return -EINVAL;
+		return -BCH_ERR_invalid_sb_crypt;
 	}
 
 	return 0;
@@ -1365,7 +1365,7 @@ static int bch2_sb_clean_validate(struct bch_sb *sb,
 	if (vstruct_bytes(&clean->field) < sizeof(*clean)) {
 		prt_printf(err, "wrong size (got %zu should be %zu)",
 		       vstruct_bytes(&clean->field), sizeof(*clean));
-		return -EINVAL;
+		return -BCH_ERR_invalid_sb_clean;
 	}
 
 	return 0;
diff --git a/fs/bcachefs/super.c b/fs/bcachefs/super.c
index 234dab15fa63..37dce3e3cccb 100644
--- a/fs/bcachefs/super.c
+++ b/fs/bcachefs/super.c
@@ -880,7 +880,7 @@ int bch2_fs_start(struct bch_fs *c)
 	struct bch_dev *ca;
 	time64_t now = ktime_get_real_seconds();
 	unsigned i;
-	int ret = -EINVAL;
+	int ret;
 
 	down_write(&c->state_lock);
 
@@ -917,9 +917,9 @@ int bch2_fs_start(struct bch_fs *c)
 	if (ret)
 		goto err;
 
-	ret = -EINVAL;
 	if (bch2_fs_init_fault("fs_start")) {
 		bch_err(c, "fs_start fault injected");
+		ret = -EINVAL;
 		goto err;
 	}
 
@@ -942,46 +942,43 @@ out:
 	return ret;
 err:
 	bch_err(c, "error starting filesystem: %s", bch2_err_str(ret));
-
-	if (ret < -BCH_ERR_START)
-		ret = -EINVAL;
 	goto out;
 }
 
-static const char *bch2_dev_may_add(struct bch_sb *sb, struct bch_fs *c)
+static int bch2_dev_may_add(struct bch_sb *sb, struct bch_fs *c)
 {
 	struct bch_sb_field_members *sb_mi;
 
 	sb_mi = bch2_sb_get_members(sb);
 	if (!sb_mi)
-		return "Invalid superblock: member info area missing";
+		return -BCH_ERR_member_info_missing;
 
 	if (le16_to_cpu(sb->block_size) != block_sectors(c))
-		return "mismatched block size";
+		return -BCH_ERR_mismatched_block_size;
 
 	if (le16_to_cpu(sb_mi->members[sb->dev_idx].bucket_size) <
 	    BCH_SB_BTREE_NODE_SIZE(c->disk_sb.sb))
-		return "new cache bucket size is too small";
+		return -BCH_ERR_bucket_size_too_small;
 
-	return NULL;
+	return 0;
 }
 
-static const char *bch2_dev_in_fs(struct bch_sb *fs, struct bch_sb *sb)
+static int bch2_dev_in_fs(struct bch_sb *fs, struct bch_sb *sb)
 {
 	struct bch_sb *newest =
 		le64_to_cpu(fs->seq) > le64_to_cpu(sb->seq) ? fs : sb;
 	struct bch_sb_field_members *mi = bch2_sb_get_members(newest);
 
 	if (!uuid_equal(&fs->uuid, &sb->uuid))
-		return "device not a member of filesystem";
+		return -BCH_ERR_device_not_a_member_of_filesystem;
 
 	if (!bch2_dev_exists(newest, mi, sb->dev_idx))
-		return "device has been removed";
+		return -BCH_ERR_device_has_been_removed;
 
 	if (fs->block_size != sb->block_size)
-		return "mismatched block size";
+		return -BCH_ERR_mismatched_block_size;
 
-	return NULL;
+	return 0;
 }
 
 /* Device startup/shutdown: */
@@ -1179,23 +1176,17 @@ static int __bch2_dev_attach_bdev(struct bch_dev *ca, struct bch_sb_handle *sb)
 	if (bch2_dev_is_online(ca)) {
 		bch_err(ca, "already have device online in slot %u",
 			sb->sb->dev_idx);
-		return -EINVAL;
+		return -BCH_ERR_device_already_online;
 	}
 
 	if (get_capacity(sb->bdev->bd_disk) <
 	    ca->mi.bucket_size * ca->mi.nbuckets) {
 		bch_err(ca, "cannot online: device too small");
-		return -EINVAL;
+		return -BCH_ERR_device_size_too_small;
 	}
 
 	BUG_ON(!percpu_ref_is_zero(&ca->io_ref));
 
-	if (get_capacity(sb->bdev->bd_disk) <
-	    ca->mi.bucket_size * ca->mi.nbuckets) {
-		bch_err(ca, "device too small");
-		return -EINVAL;
-	}
-
 	ret = bch2_dev_journal_init(ca, sb->sb);
 	if (ret)
 		return ret;
@@ -1370,7 +1361,7 @@ int __bch2_dev_set_state(struct bch_fs *c, struct bch_dev *ca,
 		return 0;
 
 	if (!bch2_dev_state_allowed(c, ca, new_state, flags))
-		return -EINVAL;
+		return -BCH_ERR_device_state_not_allowed;
 
 	if (new_state != BCH_MEMBER_STATE_rw)
 		__bch2_dev_read_only(c, ca);
@@ -1433,7 +1424,7 @@ int bch2_dev_remove(struct bch_fs *c, struct bch_dev *ca, int flags)
 {
 	struct bch_sb_field_members *mi;
 	unsigned dev_idx = ca->dev_idx, data;
-	int ret = -EINVAL;
+	int ret;
 
 	down_write(&c->state_lock);
 
@@ -1445,6 +1436,7 @@ int bch2_dev_remove(struct bch_fs *c, struct bch_dev *ca, int flags)
 
 	if (!bch2_dev_state_allowed(c, ca, BCH_MEMBER_STATE_failed, flags)) {
 		bch_err(ca, "Cannot remove without losing data");
+		ret = -BCH_ERR_device_state_not_allowed;
 		goto err;
 	}
 
@@ -1530,7 +1522,6 @@ int bch2_dev_add(struct bch_fs *c, const char *path)
 {
 	struct bch_opts opts = bch2_opts_empty();
 	struct bch_sb_handle sb;
-	const char *err;
 	struct bch_dev *ca = NULL;
 	struct bch_sb_field_members *mi;
 	struct bch_member dev_mi;
@@ -1555,10 +1546,9 @@ int bch2_dev_add(struct bch_fs *c, const char *path)
 		}
 	}
 
-	err = bch2_dev_may_add(sb.sb, c);
-	if (err) {
-		bch_err(c, "device add error: %s", err);
-		ret = -EINVAL;
+	ret = bch2_dev_may_add(sb.sb, c);
+	if (ret) {
+		bch_err(c, "device add error: %s", bch2_err_str(ret));
 		goto err;
 	}
 
@@ -1692,7 +1682,6 @@ int bch2_dev_online(struct bch_fs *c, const char *path)
 	struct bch_sb_field_members *mi;
 	struct bch_dev *ca;
 	unsigned dev_idx;
-	const char *err;
 	int ret;
 
 	down_write(&c->state_lock);
@@ -1705,9 +1694,9 @@ int bch2_dev_online(struct bch_fs *c, const char *path)
 
 	dev_idx = sb.sb->dev_idx;
 
-	err = bch2_dev_in_fs(c->disk_sb.sb, sb.sb);
-	if (err) {
-		bch_err(c, "error bringing %s online: %s", path, err);
+	ret = bch2_dev_in_fs(c->disk_sb.sb, sb.sb);
+	if (ret) {
+		bch_err(c, "error bringing %s online: %s", path, bch2_err_str(ret));
 		goto err;
 	}
 
@@ -1741,7 +1730,7 @@ int bch2_dev_online(struct bch_fs *c, const char *path)
 err:
 	up_write(&c->state_lock);
 	bch2_free_super(&sb);
-	return -EINVAL;
+	return ret;
 }
 
 int bch2_dev_offline(struct bch_fs *c, struct bch_dev *ca, int flags)
@@ -1757,7 +1746,7 @@ int bch2_dev_offline(struct bch_fs *c, struct bch_dev *ca, int flags)
 	if (!bch2_dev_state_allowed(c, ca, BCH_MEMBER_STATE_failed, flags)) {
 		bch_err(ca, "Cannot offline required disk");
 		up_write(&c->state_lock);
-		return -EINVAL;
+		return -BCH_ERR_device_state_not_allowed;
 	}
 
 	__bch2_dev_offline(c, ca);
@@ -1783,7 +1772,7 @@ int bch2_dev_resize(struct bch_fs *c, struct bch_dev *ca, u64 nbuckets)
 	    get_capacity(ca->disk_sb.bdev->bd_disk) <
 	    ca->mi.bucket_size * nbuckets) {
 		bch_err(ca, "New size larger than device");
-		ret = -EINVAL;
+		ret = -BCH_ERR_device_size_too_small;
 		goto err;
 	}
 
@@ -1836,7 +1825,6 @@ struct bch_fs *bch2_fs_open(char * const *devices, unsigned nr_devices,
 	struct bch_fs *c = NULL;
 	struct bch_sb_field_members *mi;
 	unsigned i, best_sb = 0;
-	const char *err;
 	struct printbuf errbuf = PRINTBUF;
 	int ret = 0;
 
@@ -1880,8 +1868,8 @@ struct bch_fs *bch2_fs_open(char * const *devices, unsigned nr_devices,
 			continue;
 		}
 
-		err = bch2_dev_in_fs(sb[best_sb].sb, sb[i].sb);
-		if (err)
+		ret = bch2_dev_in_fs(sb[best_sb].sb, sb[i].sb);
+		if (ret)
 			goto err_print;
 		i++;
 	}
@@ -1902,9 +1890,10 @@ struct bch_fs *bch2_fs_open(char * const *devices, unsigned nr_devices,
 	}
 	up_write(&c->state_lock);
 
-	err = "insufficient devices";
-	if (!bch2_fs_may_start(c))
+	if (!bch2_fs_may_start(c)) {
+		ret = -BCH_ERR_insufficient_devices_to_start;
 		goto err_print;
+	}
 
 	if (!c->opts.nostart) {
 		ret = bch2_fs_start(c);
@@ -1919,8 +1908,7 @@ out:
 	return c;
 err_print:
 	pr_err("bch_fs_open err opening %s: %s",
-	       devices[0], err);
-	ret = -EINVAL;
+	       devices[0], bch2_err_str(ret));
 err:
 	if (!IS_ERR_OR_NULL(c))
 		bch2_fs_stop(c);
diff --git a/fs/bcachefs/xattr.c b/fs/bcachefs/xattr.c
index bd118f6ea08b..448737be045c 100644
--- a/fs/bcachefs/xattr.c
+++ b/fs/bcachefs/xattr.c
@@ -78,7 +78,7 @@ int bch2_xattr_invalid(const struct bch_fs *c, struct bkey_s_c k,
 	if (bkey_val_bytes(k.k) < sizeof(struct bch_xattr)) {
 		prt_printf(err, "incorrect value size (%zu < %zu)",
 		       bkey_val_bytes(k.k), sizeof(*xattr.v));
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (bkey_val_u64s(k.k) <
@@ -88,7 +88,7 @@ int bch2_xattr_invalid(const struct bch_fs *c, struct bkey_s_c k,
 		       bkey_val_u64s(k.k),
 		       xattr_val_u64s(xattr.v->x_name_len,
 				      le16_to_cpu(xattr.v->x_val_len)));
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	/* XXX why +4 ? */
@@ -99,18 +99,18 @@ int bch2_xattr_invalid(const struct bch_fs *c, struct bkey_s_c k,
 		       bkey_val_u64s(k.k),
 		       xattr_val_u64s(xattr.v->x_name_len,
 				      le16_to_cpu(xattr.v->x_val_len) + 4));
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	handler = bch2_xattr_type_to_handler(xattr.v->x_type);
 	if (!handler) {
 		prt_printf(err, "invalid type (%u)", xattr.v->x_type);
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	if (memchr(xattr.v->x_name, '\0', xattr.v->x_name_len)) {
 		prt_printf(err, "xattr name has invalid characters");
-		return -EINVAL;
+		return -BCH_ERR_invalid_bkey;
 	}
 
 	return 0;