Commit a4e11cea authored by Kent Overstreet's avatar Kent Overstreet
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bcachefs: Document issue with bch_stripe layout 



We've got a problem with bch_stripe that is going to take an on disk
format rev to fix - we can't access the block sector counts if the
checksum type is unknown.

Document it for now, there are a few other things to fix as well.

Signed-off-by: default avatarKent Overstreet <kent.overstreet@linux.dev>
parent 78423deb

fs/bcachefs/ec_format.h

+17 −0
Original line number Diff line number Diff line
@@ -20,6 +20,23 @@ struct bch_stripe { 
	 */

	__u8			disk_label;



	/*

	 * Variable length sections:

	 * - Pointers

	 * - Checksums

	 *   2D array of [stripe block/device][csum block], with checksum block

	 *   size given by csum_granularity_bits

	 * - Block sector counts: per-block array of u16s

	 *

	 * XXX:

	 * Either checksums should have come last, or we should have included a

	 * checksum_size field (the size in bytes of the checksum itself, not

	 * the blocksize the checksum covers).

	 *

	 * Currently we aren't able to access the block sector counts if the

	 * checksum type is unknown.

	 */



	struct bch_extent_ptr	ptrs[];

} __packed __aligned(8);