package/boot/uboot-mediatek/patches/100-27-mtd-ubi-add-support-for-UBI-end-of-filesystem-marker.patch

   1 From 189a2fe96931ef3ea0e187c8e9bfa589c2a0ae10 Mon Sep 17 00:00:00 2001
   2 From: Weijie Gao <weijie.gao@mediatek.com>
   3 Date: Mon, 25 Jul 2022 17:24:56 +0800
   4 Subject: [PATCH 62/71] mtd: ubi: add support for UBI end-of-filesystem marker
   5  used by OpenWrt
   6
   7 Add support for UBI end-of-filesystem marker used by OpenWrt to allow
   8 attaching a new UBI mtd partition just upgraded.
   9
  10 Signed-off-by: Weijie Gao <weijie.gao@mediatek.com>
  11 ---
  12  drivers/mtd/ubi/attach.c | 25 ++++++++++++++++++++++---
  13  drivers/mtd/ubi/ubi.h    |  1 +
  14  2 files changed, 23 insertions(+), 3 deletions(-)
  15
  16 --- a/drivers/mtd/ubi/attach.c
  17 +++ b/drivers/mtd/ubi/attach.c
  18 @@ -802,6 +802,13 @@ out_unlock:
  19         return err;
  20  }
  21
  22 +static bool ec_hdr_has_eof(struct ubi_ec_hdr *ech)
  23 +{
  24 +       return ech->padding1[0] == 'E' &&
  25 +              ech->padding1[1] == 'O' &&
  26 +              ech->padding1[2] == 'F';
  27 +}
  28 +
  29  /**
  30   * scan_peb - scan and process UBI headers of a PEB.
  31   * @ubi: UBI device description object
  32 @@ -832,9 +839,21 @@ static int scan_peb(struct ubi_device *u
  33                 return 0;
  34         }
  35
  36 -       err = ubi_io_read_ec_hdr(ubi, pnum, ech, 0);
  37 -       if (err < 0)
  38 -               return err;
  39 +       if (!ai->eof_found) {
  40 +               err = ubi_io_read_ec_hdr(ubi, pnum, ech, 0);
  41 +               if (err < 0)
  42 +                       return err;
  43 +
  44 +               if (ec_hdr_has_eof(ech)) {
  45 +                       pr_notice("UBI: EOF marker found, PEBs from %d will be erased\n",
  46 +                               pnum);
  47 +                       ai->eof_found = true;
  48 +               }
  49 +       }
  50 +
  51 +       if (ai->eof_found)
  52 +               err = UBI_IO_FF_BITFLIPS;
  53 +
  54         switch (err) {
  55         case 0:
  56                 break;
  57 --- a/drivers/mtd/ubi/ubi.h
  58 +++ b/drivers/mtd/ubi/ubi.h
  59 @@ -745,6 +745,7 @@ struct ubi_attach_info {
  60         int mean_ec;
  61         uint64_t ec_sum;
  62         int ec_count;
  63 +       bool eof_found;
  64         struct kmem_cache *aeb_slab_cache;
  65  };
  66