[PATCH 8/9] drivers:mtd:ubi:init UBI bakvol and recover corrupted lower page

[beanhuo]

During UBI attach, bakvol be initialized,
And if exist corrupted lower page, recover it by its backup data in internal 
Log volume.

Signed-off-by: Bean Huo <bean...@micron.com>
---
 drivers/mtd/ubi/attach.c | 26 +++++++++++++++++++++++++-
 drivers/mtd/ubi/build.c  |  7 +++++++
 2 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/drivers/mtd/ubi/attach.c b/drivers/mtd/ubi/attach.c
index 68eea5b..4e00d79 100644
--- a/drivers/mtd/ubi/attach.c
+++ b/drivers/mtd/ubi/attach.c
@@ -919,6 +919,17 @@ static int scan_peb(struct ubi_device *ubi, struct 
ubi_attach_info *ai,
        err = ubi_io_read_vid_hdr(ubi, pnum, vidh, 0);
        if (err < 0)
                return err;
+
+#ifdef CONFIG_MTD_UBI_MLC_NAND_BAKVOL
+       /*
+        * Before ubi scan the NAND flash, call ubi_backup_volume_scan
+        * to build the backup volume first. when the ubi scan NAND and
+        * find corrupt data, then we can try to check if there is backup
+        * data in the backup volume.
+        */
+       ubi_backup_volume_scan(ubi, vidh, pnum);
+#endif
+
        switch (err) {
        case 0:
                break;
@@ -995,7 +1006,8 @@ static int scan_peb(struct ubi_device *ubi, struct 
ubi_attach_info *ai,
                *vid = vol_id;
        if (sqnum)
                *sqnum = be64_to_cpu(vidh->sqnum);
-       if (vol_id > UBI_MAX_VOLUMES && vol_id != UBI_LAYOUT_VOLUME_ID) {
+       if ((vol_id > UBI_MAX_VOLUMES && vol_id != UBI_LAYOUT_VOLUME_ID)
+                                       && vol_id != UBI_BACKUP_VOLUME_ID) {
                int lnum = be32_to_cpu(vidh->lnum);
 
                /* Unsupported internal volume */
@@ -1408,6 +1420,12 @@ int ubi_attach(struct ubi_device *ubi, int force_scan)
        if (!ai)
                return -ENOMEM;
 
+#ifdef CONFIG_MTD_UBI_MLC_NAND_BAKVOL
+       err = ubi_backup_volume_init(ubi);
+       if (err)
+               goto out_ai;
+#endif
+
 #ifdef CONFIG_MTD_UBI_FASTMAP
        /* On small flash devices we disable fastmap in any case. */
        if ((int)mtd_div_by_eb(ubi->mtd->size, ubi->mtd) <= UBI_FM_MAX_START) {
@@ -1449,6 +1467,12 @@ int ubi_attach(struct ubi_device *ubi, int force_scan)
        if (err)
                goto out_ai;
 
+#ifdef CONFIG_MTD_UBI_MLC_NAND_BAKVOL
+       err = ubi_backup_volume_init_tail(ubi, ai);
+       if (err)
+               goto out_ai;
+#endif
+
        err = ubi_wl_init(ubi, ai);
        if (err)
                goto out_vtbl;
diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c
index 22fd19c..05524f7 100644
--- a/drivers/mtd/ubi/build.c
+++ b/drivers/mtd/ubi/build.c
@@ -1033,6 +1033,11 @@ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
 
        ubi_devices[ubi_num] = ubi;
        ubi_notify_all(ubi, UBI_VOLUME_ADDED, NULL);
+
+#ifdef CONFIG_MTD_UBI_MLC_NAND_BAKVOL
+       ubi_bad_data_recovery(ubi);
+#endif
+
        return ubi_num;
 
 out_debugfs:
@@ -1118,6 +1123,8 @@ int ubi_detach_mtd_dev(int ubi_num, int anyway)
         */
        get_device(&ubi->dev);
 
+       clear_bakvol(ubi);
+
        ubi_debugfs_exit_dev(ubi);
        uif_close(ubi);
 
-- 
1.9.1