UBI: remove pre-sqnum images support

Before UBI got into mainline, there was a slight flash format
change - we did not have sequence number support, then added it.

We have carried full support of those ancient images till this
moment. Now the support is removed, well, not fully removed.

Now UBI will support only _clean_ old images, which were cleanly
detached last time (just before kernel upgrade). This is most
likely the case.

But we will not support unclean ancient images. Surprisingly,
this allows us to remove a big chunk of legacy code.

And the same should be true for downgrading: clean images should
downgrade fine, but unclean ones will not.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

1 files changed, 6 insertions, 11 deletions

diff --git a/drivers/mtd/ubi/ubi-media.h b/drivers/mtd/ubi/ubi-media.h
index 26bb7af9787a..2ad940409053 100644
--- a/drivers/mtd/ubi/ubi-media.h
+++ b/drivers/mtd/ubi/ubi-media.h
@@ -168,16 +168,15 @@ struct ubi_ec_hdr {
  *          %UBI_COMPAT_IGNORE, %UBI_COMPAT_PRESERVE, or %UBI_COMPAT_REJECT)
  * @vol_id: ID of this volume
  * @lnum: logical eraseblock number
- * @leb_ver: version of this logical eraseblock (IMPORTANT: obsolete, to be
- *           removed, kept only for not breaking older UBI users)
+ * @padding1: reserved for future, zeroes
  * @data_size: how many bytes of data this logical eraseblock contains
  * @used_ebs: total number of used logical eraseblocks in this volume
  * @data_pad: how many bytes at the end of this physical eraseblock are not
  *            used
  * @data_crc: CRC checksum of the data stored in this logical eraseblock
- * @padding1: reserved for future, zeroes
- * @sqnum: sequence number
  * @padding2: reserved for future, zeroes
+ * @sqnum: sequence number
+ * @padding3: reserved for future, zeroes
  * @hdr_crc: volume identifier header CRC checksum
  *
  * The @sqnum is the value of the global sequence counter at the time when this
@@ -225,10 +224,6 @@ struct ubi_ec_hdr {
  * checksum is correct, this physical eraseblock is selected (P1). Otherwise
  * the older one (P) is selected.
  *
- * Note, there is an obsolete @leb_ver field which was used instead of @sqnum
- * in the past. But it is not used anymore and we keep it in order to be able
- * to deal with old UBI images. It will be removed at some point.
- *
  * There are 2 sorts of volumes in UBI: user volumes and internal volumes.
  * Internal volumes are not seen from outside and are used for various internal
  * UBI purposes. In this implementation there is only one internal volume - the
@@ -278,14 +273,14 @@ struct ubi_vid_hdr {
         __u8    compat;
         __be32  vol_id;
         __be32  lnum;
-        __be32  leb_ver; /* obsolete, to be removed, don't use */
+        __u8    padding1[4];
         __be32  data_size;
         __be32  used_ebs;
         __be32  data_pad;
         __be32  data_crc;
-        __u8    padding1[4];
+        __u8    padding2[4];
         __be64  sqnum;
-        __u8    padding2[12];
+        __u8    padding3[12];
         __be32  hdr_crc;
 } __attribute__ ((packed));