target/linux/generic-2.4/patches/227-jffs2_eofdetect.patch

   1 diff -ur linux.old/fs/jffs2/scan.c linux.dev/fs/jffs2/scan.c
   2 --- linux.old/fs/jffs2/scan.c   2003-11-28 19:26:21.000000000 +0100
   3 +++ linux.dev/fs/jffs2/scan.c   2006-06-22 00:29:02.000000000 +0200
   4 @@ -31,6 +31,10 @@
   5   * provisions above, a recipient may use your version of this file
   6   * under either the RHEPL or the GPL.
   7   *
   8 + * Modification for automatically cleaning the filesystem after
   9 + * a specially marked block
  10 + * Copyright (C) 2006 Felix Fietkau <nbd@openwrt.org>
  11 + *
  12   * $Id: scan.c,v 1.51.2.4 2003/11/02 13:51:18 dwmw2 Exp $
  13   *
  14   */
  15 @@ -88,7 +92,12 @@
  16         for (i=0; i<c->nr_blocks; i++) {
  17                 struct jffs2_eraseblock *jeb = &c->blocks[i];
  18
  19 -               ret = jffs2_scan_eraseblock(c, jeb);
  20 +
  21 +               if (c->flags & (1 << 7))
  22 +                       ret = 1;
  23 +               else
  24 +                       ret = jffs2_scan_eraseblock(c, jeb);
  25 +
  26                 if (ret < 0)
  27                         return ret;
  28
  29 @@ -145,15 +154,23 @@
  30                         c->nr_erasing_blocks++;
  31                 }
  32         }
  33 -       /* Rotate the lists by some number to ensure wear levelling */
  34 -       jffs2_rotate_lists(c);
  35
  36 -       if (c->nr_erasing_blocks) {
  37 -               if (!c->used_size && empty_blocks != c->nr_blocks) {
  38 -                       printk(KERN_NOTICE "Cowardly refusing to erase blocks on filesystem with no valid JFFS2 nodes\n");
  39 -                       return -EIO;
  40 +       if (c->flags & (1 << 7)) {
  41 +               printk("jffs2_scan_medium(): erasing all blocks after the end marker...\n");
  42 +               jffs2_erase_pending_blocks(c);
  43 +               jffs2_mark_erased_blocks(c);
  44 +               printk("jffs2_scan_medium(): done.\n");
  45 +       } else {
  46 +               /* Rotate the lists by some number to ensure wear levelling */
  47 +               jffs2_rotate_lists(c);
  48 +
  49 +               if (c->nr_erasing_blocks) {
  50 +                       if (!c->used_size && empty_blocks != c->nr_blocks) {
  51 +                               printk(KERN_NOTICE "Cowardly refusing to erase blocks on filesystem with no valid JFFS2 nodes\n");
  52 +                               return -EIO;
  53 +                       }
  54 +                       jffs2_erase_pending_trigger(c);
  55                 }
  56 -               jffs2_erase_pending_trigger(c);
  57         }
  58         return 0;
  59  }
  60 @@ -181,6 +197,7 @@
  61
  62         while(ofs < jeb->offset + c->sector_size) {
  63                 ssize_t retlen;
  64 +               unsigned char *buf = (unsigned char *) &node;
  65                 ACCT_PARANOIA_CHECK(jeb);
  66
  67                 if (ofs & 3) {
  68 @@ -202,8 +219,18 @@
  69                         break;
  70                 }
  71
  72 -               err = c->mtd->read(c->mtd, ofs, sizeof(node), &retlen, (char *)&node);
  73 +               err = c->mtd->read(c->mtd, ofs, sizeof(node), &retlen, buf);
  74 +               if ((buf[0] == 0xde) &&
  75 +                       (buf[1] == 0xad) &&
  76 +                       (buf[2] == 0xc0) &&
  77 +                       (buf[3] == 0xde)) {
  78 +
  79 +                       /* end of filesystem. erase everything after this point */
  80 +                       c->flags |= (1 << 7);
  81 +                       printk("jffs2_scan_eraseblock(): End of filesystem marker found at 0x%x\n", jeb->offset);
  82
  83 +                       return 1;
  84 +               }
  85                 if (err) {
  86                         D1(printk(KERN_WARNING "mtd->read(0x%x bytes from 0x%x) returned %d\n", sizeof(node), ofs, err));
  87                         return err;
  88