[PATCH v2 12/12] ubi: fastmap: Add all fastmap pebs into 'ai->fastmap' when fm->used_blocks>=2

[Zhihao Cheng]

Fastmap pebs(pnum >= UBI_FM_MAX_START) won't be added into 'ai->fastmap'
while attaching ubi device if 'fm->used_blocks' is greater than 2, which
may cause warning from 'ubi_assert(ubi->good_peb_count == found_pebs)':

  UBI assert failed in ubi_wl_init at 1878 (pid 2409)
  Call Trace:
    ubi_wl_init.cold+0xae/0x2af [ubi]
    ubi_attach+0x1b0/0x780 [ubi]
    ubi_init+0x23a/0x3ad [ubi]
    load_module+0x22d2/0x2430

Reproduce:
  ID="0x20,0x33,0x00,0x00" # 16M 16KB PEB, 512 page
  modprobe nandsim id_bytes=$ID
  modprobe ubi mtd="0,0" fm_autoconvert  # Fastmap takes 2 pebs
  rmmod ubi
  modprobe ubi mtd="0,0" fm_autoconvert  # Attach by fastmap

Add all fastmap pebs into list 'ai->fastmap' to make sure they can be
counted into 'found_pebs'.

Fixes: fdf10ed710c0aa ("ubi: Rework Fastmap attach base code")
Signed-off-by: Zhihao Cheng <chengzhihao1@xxxxxxxxxx>
---
 drivers/mtd/ubi/fastmap.c | 41 ++++++++++++++-------------------------
 1 file changed, 15 insertions(+), 26 deletions(-)

diff --git a/drivers/mtd/ubi/fastmap.c b/drivers/mtd/ubi/fastmap.c
index 6b5f1ffd961b..88fdf8f5709f 100644
--- a/drivers/mtd/ubi/fastmap.c
+++ b/drivers/mtd/ubi/fastmap.c
@@ -828,24 +828,6 @@ static int find_fm_anchor(struct ubi_attach_info *ai)
 	return ret;
 }
 
-static struct ubi_ainf_peb *clone_aeb(struct ubi_attach_info *ai,
-				      struct ubi_ainf_peb *old)
-{
-	struct ubi_ainf_peb *new;
-
-	new = ubi_alloc_aeb(ai, old->pnum, old->ec);
-	if (!new)
-		return NULL;
-
-	new->vol_id = old->vol_id;
-	new->sqnum = old->sqnum;
-	new->lnum = old->lnum;
-	new->scrub = old->scrub;
-	new->copy_flag = old->copy_flag;
-
-	return new;
-}
-
 /**
  * ubi_scan_fastmap - scan the fastmap.
  * @ubi: UBI device object
@@ -875,15 +857,11 @@ int ubi_scan_fastmap(struct ubi_device *ubi, struct ubi_attach_info *ai,
 	if (fm_anchor < 0)
 		return UBI_NO_FASTMAP;
 
-	/* Copy all (possible) fastmap blocks into our new attach structure. */
+	/* Add fastmap blocks(pnum < UBI_FM_MAX_START) into attach structure. */
 	list_for_each_entry(aeb, &scan_ai->fastmap, u.list) {
-		struct ubi_ainf_peb *new;
-
-		new = clone_aeb(ai, aeb);
-		if (!new)
-			return -ENOMEM;
-
-		list_add(&new->u.list, &ai->fastmap);
+		ret = add_aeb(ai, &ai->fastmap, aeb->pnum, aeb->ec, 0);
+		if (ret)
+			return ret;
 	}
 
 	down_write(&ubi->fm_protect);
@@ -1029,6 +1007,17 @@ int ubi_scan_fastmap(struct ubi_device *ubi, struct ubi_attach_info *ai,
 				"err: %i)", i, pnum, ret);
 			goto free_hdr;
 		}
+
+		/*
+		 * Add left fastmap blocks (pnum >= UBI_FM_MAX_START) into
+		 * attach structure.
+		 */
+		if (pnum >= UBI_FM_MAX_START) {
+			ret = add_aeb(ai, &ai->fastmap, pnum,
+				      be64_to_cpu(ech->ec), 0);
+			if (ret)
+				goto free_hdr;
+		}
 	}
 
 	kfree(fmsb);
-- 
2.31.1