ubi: Rework Fastmap attach base code
Introduce a new list to the UBI attach information
object to be able to deal better with old and corrupted
Fastmap eraseblocks.
Also move more Fastmap specific code into fastmap.c.
Signed-off-by: Richard Weinberger <richard@nod.at>
diff --git a/drivers/mtd/ubi/fastmap.c b/drivers/mtd/ubi/fastmap.c
index ab337e6..12bdb09 100644
--- a/drivers/mtd/ubi/fastmap.c
+++ b/drivers/mtd/ubi/fastmap.c
@@ -850,27 +850,57 @@
}
/**
+ * find_fm_anchor - find the most recent Fastmap superblock (anchor)
+ * @ai: UBI attach info to be filled
+ */
+static int find_fm_anchor(struct ubi_attach_info *ai)
+{
+ int ret = -1;
+ struct ubi_ainf_peb *aeb;
+ unsigned long long max_sqnum = 0;
+
+ list_for_each_entry(aeb, &ai->fastmap, u.list) {
+ if (aeb->vol_id == UBI_FM_SB_VOLUME_ID && aeb->sqnum > max_sqnum) {
+ max_sqnum = aeb->sqnum;
+ ret = aeb->pnum;
+ }
+ }
+
+ return ret;
+}
+
+/**
* ubi_scan_fastmap - scan the fastmap.
* @ubi: UBI device object
* @ai: UBI attach info to be filled
- * @fm_anchor: The fastmap starts at this PEB
+ * @scan_ai: UBI attach info from the first 64 PEBs,
+ * used to find the most recent Fastmap data structure
*
* Returns 0 on success, UBI_NO_FASTMAP if no fastmap was found,
* UBI_BAD_FASTMAP if one was found but is not usable.
* < 0 indicates an internal error.
*/
int ubi_scan_fastmap(struct ubi_device *ubi, struct ubi_attach_info *ai,
- int fm_anchor)
+ struct ubi_attach_info *scan_ai)
{
struct ubi_fm_sb *fmsb, *fmsb2;
struct ubi_vid_hdr *vh;
struct ubi_ec_hdr *ech;
struct ubi_fastmap_layout *fm;
- int i, used_blocks, pnum, ret = 0;
+ struct ubi_ainf_peb *tmp_aeb, *aeb;
+ int i, used_blocks, pnum, fm_anchor, ret = 0;
size_t fm_size;
__be32 crc, tmp_crc;
unsigned long long sqnum = 0;
+ fm_anchor = find_fm_anchor(scan_ai);
+ if (fm_anchor < 0)
+ return UBI_NO_FASTMAP;
+
+ /* Move all (possible) fastmap blocks into our new attach structure. */
+ list_for_each_entry_safe(aeb, tmp_aeb, &scan_ai->fastmap, u.list)
+ list_move_tail(&aeb->u.list, &ai->fastmap);
+
down_write(&ubi->fm_protect);
memset(ubi->fm_buf, 0, ubi->fm_size);