Merge tag 'for-6.13-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:

 - tree-checker catches invalid number of inline extent references

 - zoned mode fixes:
    - enhance zone append IO command so it also detects emulated writes
    - handle bio splitting at sectorsize boundary

 - when deleting a snapshot, fix a condition for visiting nodes in reloc
   trees

* tag 'for-6.13-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: tree-checker: reject inline extent items with 0 ref count
  btrfs: split bios to the fs sector size boundary
  btrfs: use bio_is_zone_append() in the completion handler
  btrfs: fix improper generation check in snapshot delete

Author: torvalds

fs/btrfs/bio.c

@@ -358,7 +358,7 @@ static void btrfs_simple_end_io(struct bio *bio)
 		INIT_WORK(&bbio->end_io_work, btrfs_end_bio_work);
 		queue_work(btrfs_end_io_wq(fs_info, bio), &bbio->end_io_work);
 	} else {
-		if (bio_op(bio) == REQ_OP_ZONE_APPEND && !bio->bi_status)
+		if (bio_is_zone_append(bio) && !bio->bi_status)
 			btrfs_record_physical_zoned(bbio);
 		btrfs_bio_end_io(bbio, bbio->bio.bi_status);
 	}
@@ -401,7 +401,7 @@ static void btrfs_orig_write_end_io(struct bio *bio)
 	else
 		bio->bi_status = BLK_STS_OK;
 
-	if (bio_op(bio) == REQ_OP_ZONE_APPEND && !bio->bi_status)
+	if (bio_is_zone_append(bio) && !bio->bi_status)
 		stripe->physical = bio->bi_iter.bi_sector << SECTOR_SHIFT;
 
 	btrfs_bio_end_io(bbio, bbio->bio.bi_status);
@@ -415,7 +415,7 @@ static void btrfs_clone_write_end_io(struct bio *bio)
 	if (bio->bi_status) {
 		atomic_inc(&stripe->bioc->error);
 		btrfs_log_dev_io_error(bio, stripe->dev);
-	} else if (bio_op(bio) == REQ_OP_ZONE_APPEND) {
+	} else if (bio_is_zone_append(bio)) {
 		stripe->physical = bio->bi_iter.bi_sector << SECTOR_SHIFT;
 	}
 
@@ -652,8 +652,14 @@ static u64 btrfs_append_map_length(struct btrfs_bio *bbio, u64 map_length)
 	map_length = min(map_length, bbio->fs_info->max_zone_append_size);
 	sector_offset = bio_split_rw_at(&bbio->bio, &bbio->fs_info->limits,
 					&nr_segs, map_length);
-	if (sector_offset)
-		return sector_offset << SECTOR_SHIFT;
+	if (sector_offset) {
+		/*
+		 * bio_split_rw_at() could split at a size smaller than our
+		 * sectorsize and thus cause unaligned I/Os.  Fix that by
+		 * always rounding down to the nearest boundary.
+		 */
+		return ALIGN_DOWN(sector_offset << SECTOR_SHIFT, bbio->fs_info->sectorsize);
+	}
 	return map_length;
 }
 

fs/btrfs/ctree.h

@@ -370,6 +370,25 @@ static inline void btrfs_set_root_last_trans(struct btrfs_root *root, u64 transi
 	WRITE_ONCE(root->last_trans, transid);
 }
 
+/*
+ * Return the generation this root started with.
+ *
+ * Every normal root that is created with root->root_key.offset set to it's
+ * originating generation.  If it is a snapshot it is the generation when the
+ * snapshot was created.
+ *
+ * However for TREE_RELOC roots root_key.offset is the objectid of the owning
+ * tree root.  Thankfully we copy the root item of the owning tree root, which
+ * has it's last_snapshot set to what we would have root_key.offset set to, so
+ * return that if this is a TREE_RELOC root.
+ */
+static inline u64 btrfs_root_origin_generation(const struct btrfs_root *root)
+{
+	if (btrfs_root_id(root) == BTRFS_TREE_RELOC_OBJECTID)
+		return btrfs_root_last_snapshot(&root->root_item);
+	return root->root_key.offset;
+}
+
 /*
  * Structure that conveys information about an extent that is going to replace
  * all the extents in a file range.

fs/btrfs/extent-tree.c

@@ -5285,7 +5285,7 @@ static bool visit_node_for_delete(struct btrfs_root *root, struct walk_control *
 	 * reference to it.
 	 */
 	generation = btrfs_node_ptr_generation(eb, slot);
-	if (!wc->update_ref || generation <= root->root_key.offset)
+	if (!wc->update_ref || generation <= btrfs_root_origin_generation(root))
 		return false;
 
 	/*
@@ -5340,7 +5340,7 @@ static noinline void reada_walk_down(struct btrfs_trans_handle *trans,
 			goto reada;
 
 		if (wc->stage == UPDATE_BACKREF &&
-		    generation <= root->root_key.offset)
+		    generation <= btrfs_root_origin_generation(root))
 			continue;
 
 		/* We don't lock the tree block, it's OK to be racy here */
@@ -5683,7 +5683,7 @@ static noinline int do_walk_down(struct btrfs_trans_handle *trans,
 	 * for the subtree
 	 */
 	if (wc->stage == UPDATE_BACKREF &&
-	    generation <= root->root_key.offset) {
+	    generation <= btrfs_root_origin_generation(root)) {
 		wc->lookup_info = 1;
 		return 1;
 	}

fs/btrfs/tree-checker.c

@@ -1527,6 +1527,11 @@ static int check_extent_item(struct extent_buffer *leaf,
 					   dref_offset, fs_info->sectorsize);
 				return -EUCLEAN;
 			}
+			if (unlikely(btrfs_extent_data_ref_count(leaf, dref) == 0)) {
+				extent_err(leaf, slot,
+			"invalid data ref count, should have non-zero value");
+				return -EUCLEAN;
+			}
 			inline_refs += btrfs_extent_data_ref_count(leaf, dref);
 			break;
 		/* Contains parent bytenr and ref count */
@@ -1539,6 +1544,11 @@ static int check_extent_item(struct extent_buffer *leaf,
 					   inline_offset, fs_info->sectorsize);
 				return -EUCLEAN;
 			}
+			if (unlikely(btrfs_shared_data_ref_count(leaf, sref) == 0)) {
+				extent_err(leaf, slot,
+			"invalid shared data ref count, should have non-zero value");
+				return -EUCLEAN;
+			}
 			inline_refs += btrfs_shared_data_ref_count(leaf, sref);
 			break;
 		case BTRFS_EXTENT_OWNER_REF_KEY:
@@ -1611,8 +1621,18 @@ static int check_simple_keyed_refs(struct extent_buffer *leaf,
 {
 	u32 expect_item_size = 0;
 
-	if (key->type == BTRFS_SHARED_DATA_REF_KEY)
+	if (key->type == BTRFS_SHARED_DATA_REF_KEY) {
+		struct btrfs_shared_data_ref *sref;
+
+		sref = btrfs_item_ptr(leaf, slot, struct btrfs_shared_data_ref);
+		if (unlikely(btrfs_shared_data_ref_count(leaf, sref) == 0)) {
+			extent_err(leaf, slot,
+		"invalid shared data backref count, should have non-zero value");
+			return -EUCLEAN;
+		}
+
 		expect_item_size = sizeof(struct btrfs_shared_data_ref);
+	}
 
 	if (unlikely(btrfs_item_size(leaf, slot) != expect_item_size)) {
 		generic_err(leaf, slot,
@@ -1689,6 +1709,11 @@ static int check_extent_data_ref(struct extent_buffer *leaf,
 				   offset, leaf->fs_info->sectorsize);
 			return -EUCLEAN;
 		}
+		if (unlikely(btrfs_extent_data_ref_count(leaf, dref) == 0)) {
+			extent_err(leaf, slot,
+	"invalid extent data backref count, should have non-zero value");
+			return -EUCLEAN;
+		}
 	}
 	return 0;
 }