target/linux/generic/pending-4.9/532-jffs2_eofdetect.patch

   1 From: Felix Fietkau <nbd@nbd.name>
   2 Subject: fs: jffs2: EOF marker
   3
   4 Signed-off-by: Felix Fietkau <nbd@nbd.name>
   5 ---
   6  fs/jffs2/build.c | 10 ++++++++++
   7  fs/jffs2/scan.c  | 21 +++++++++++++++++++--
   8  2 files changed, 29 insertions(+), 2 deletions(-)
   9
  10 diff --git a/fs/jffs2/build.c b/fs/jffs2/build.c
  11 index b288c8ae1236..e768f9d41661 100644
  12 --- a/fs/jffs2/build.c
  13 +++ b/fs/jffs2/build.c
  14 @@ -117,6 +117,16 @@ static int jffs2_build_filesystem(struct jffs2_sb_info *c)
  15         dbg_fsbuild("scanned flash completely\n");
  16         jffs2_dbg_dump_block_lists_nolock(c);
  17
  18 +       if (c->flags & (1 << 7)) {
  19 +               printk("%s(): unlocking the mtd device... ", __func__);
  20 +               mtd_unlock(c->mtd, 0, c->mtd->size);
  21 +               printk("done.\n");
  22 +
  23 +               printk("%s(): erasing all blocks after the end marker... ", __func__);
  24 +               jffs2_erase_pending_blocks(c, -1);
  25 +               printk("done.\n");
  26 +       }
  27 +
  28         dbg_fsbuild("pass 1 starting\n");
  29         c->flags |= JFFS2_SB_FLAG_BUILDING;
  30         /* Now scan the directory tree, increasing nlink according to every dirent found. */
  31 diff --git a/fs/jffs2/scan.c b/fs/jffs2/scan.c
  32 index 90431dd613b8..8c78ab19cdab 100644
  33 --- a/fs/jffs2/scan.c
  34 +++ b/fs/jffs2/scan.c
  35 @@ -148,8 +148,14 @@ int jffs2_scan_medium(struct jffs2_sb_info *c)
  36                 /* reset summary info for next eraseblock scan */
  37                 jffs2_sum_reset_collected(s);
  38
  39 -               ret = jffs2_scan_eraseblock(c, jeb, buf_size?flashbuf:(flashbuf+jeb->offset),
  40 -                                               buf_size, s);
  41 +               if (c->flags & (1 << 7)) {
  42 +                       if (mtd_block_isbad(c->mtd, jeb->offset))
  43 +                               ret = BLK_STATE_BADBLOCK;
  44 +                       else
  45 +                               ret = BLK_STATE_ALLFF;
  46 +               } else
  47 +                       ret = jffs2_scan_eraseblock(c, jeb, buf_size?flashbuf:(flashbuf+jeb->offset),
  48 +                                                       buf_size, s);
  49
  50                 if (ret < 0)
  51                         goto out;
  52 @@ -561,6 +567,17 @@ static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblo
  53                         return err;
  54         }
  55
  56 +       if ((buf[0] == 0xde) &&
  57 +               (buf[1] == 0xad) &&
  58 +               (buf[2] == 0xc0) &&
  59 +               (buf[3] == 0xde)) {
  60 +               /* end of filesystem. erase everything after this point */
  61 +               printk("%s(): End of filesystem marker found at 0x%x\n", __func__, jeb->offset);
  62 +               c->flags |= (1 << 7);
  63 +
  64 +               return BLK_STATE_ALLFF;
  65 +       }
  66 +
  67         /* We temporarily use 'ofs' as a pointer into the buffer/jeb */
  68         ofs = 0;
  69         max_ofs = EMPTY_SCAN_SIZE(c->sector_size);
  70 --
  71 2.11.0
  72