Re: [PATCH] Re: Lost Partition

[Vincent Sweeney <v.sweeney@dexterus.com>]

No luck I'm afraid. The patch applied successfully bit I still get
exactly the same problem.

Vince.

Alexander Viro wrote:
> 
> On Thu, 11 Oct 2001, Vincent Sweeney wrote:
> 
> > I have just upgrade my kernel to 2.4.12 and in the process I've lost a
> > partition on my secondary IDE drive. Since this is my /usr partition
> > it's kind of important ;)
> 
> Please, see if the following fixes the problem.
> 
> --- S11/fs/partitions/msdos.c   Tue Oct  9 21:47:27 2001
> +++ /tmp/msdos.c        Thu Oct 11 09:18:22 2001
> @@ -103,21 +103,20 @@
>   */
> 
>  static void extended_partition(struct gendisk *hd, struct block_device *bdev,
> -                               int minor, int *current_minor)
> +                       int minor, unsigned long first_size, int *current_minor)
>  {
>         struct partition *p;
>         Sector sect;
>         unsigned char *data;
> -       unsigned long first_sector, first_size, this_sector, this_size;
> +       unsigned long first_sector, this_sector, this_size;
>         int mask = (1 << hd->minor_shift) - 1;
>         int sector_size = get_hardsect_size(to_kdev_t(bdev->bd_dev)) / 512;
>         int loopct = 0;         /* number of links followed
>                                    without finding a data partition */
>         int i;
> 
> -       first_sector = hd->part[minor].start_sect;
> -       first_size = hd->part[minor].nr_sects;
> -       this_sector = first_sector;
> +       this_sector = first_sector = hd->part[minor].start_sect;
> +       this_size = first_size;
> 
>         while (1) {
>                 if (++loopct > 100)
> @@ -133,8 +132,6 @@
> 
>                 p = (struct partition *) (data + 0x1be);
> 
> -               this_size = hd->part[minor].nr_sects;
> -
>                 /*
>                  * Usually, the first entry is the real data partition,
>                  * the 2nd entry is the next extended partition, or empty,
> @@ -196,6 +193,7 @@
>                         goto done;       /* nothing left to do */
> 
>                 this_sector = first_sector + START_SECT(p) * sector_size;
> +               this_size = NR_SECTS(p) * sector_size;
>                 minor = *current_minor;
>                 put_dev_sector(sect);
>         }
> @@ -586,12 +584,13 @@
>                 }
>  #endif
>                 if (is_extended_partition(p)) {
> +                       unsigned long size = hd->part[minor].nr_sects;
>                         printk(" <");
>                         /* prevent someone doing mkfs or mkswap on an
>                            extended partition, but leave room for LILO */
> -                       if (hd->part[minor].nr_sects > 2)
> +                       if (size > 2)
>                                 hd->part[minor].nr_sects = 2;
> -                       extended_partition(hd, bdev, minor, &current_minor);
> +                       extended_partition(hd, bdev, minor, size, &current_minor);
>                         printk(" >");
>                 }
>         }