Re: [PATCH 1/1] add --partuuid to probe

[Andrei Borzenkov]

14.02.2017 21:00, Steve Kenton пишет:
> Support both EFI and NT Disk Signature for passing to kernel as 
> root=PARTUUID=$val
> 

Yes, I guess we need to add it finally. Unfortunately it is too late for
2.02, but it should go after in release. There were also patches for
grub-probe and we also need to support it in search to be on par with
filesystem UUID. May be if you could prepare consolidated patch set it
would be great.

I apologize that it tool so long. Thank you for not giving up!

> Signed-off-by: Steve Kenton <address@hidden>
> ---
> It's been six months so I thought I'd resend this so it does not get lost
> in case I get hit by a meteor or something before the next release
> 
>  grub-core/commands/probe.c | 53 
> ++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 53 insertions(+)
> 
> diff --git a/grub-core/commands/probe.c b/grub-core/commands/probe.c
> index cf2793e..3afc8b8 100644
> --- a/grub-core/commands/probe.c
> +++ b/grub-core/commands/probe.c

Please also add patch for manual.

> @@ -45,6 +45,7 @@ static const struct grub_arg_option options[] =
>      {"fs",           'f', 0, N_("Determine filesystem type."), 0, 0},
>      {"fs-uuid",              'u', 0, N_("Determine filesystem UUID."), 0, 0},
>      {"label",                'l', 0, N_("Determine filesystem label."), 0, 
> 0},
> +    {"partuuid",     'g', 0, N_("Determine partition GUID/UUID."), 0, 0}, /* 
> GUID but Linux kernel calls it "PARTUUID" */
>      {0, 0, 0, 0, 0, 0}
>    };
>  
> @@ -154,6 +155,58 @@ grub_cmd_probe (grub_extcmd_context_t ctxt, int argc, 
> char **args)
>        grub_device_close (dev);
>        return GRUB_ERR_NONE;
>      }
> +  if (state[6].set)
> +    {
> +      char *partuuid = NULL; /* NULL to silence a spurious GCC warning */
> +      grub_uint8_t diskbuf[16];
> +      if (dev->disk && dev->disk->partition)
> +     {
> +       grub_partition_t p = dev->disk->partition;
> +       if (!grub_strcmp (p->partmap->name, "msdos"))
> +         {
> +           const int diskid_offset = 440; /* location in MBR */
> +           dev->disk->partition = p->parent;
> +           /* little-endian 4-byte NT disk signature */
> +           err = grub_disk_read (dev->disk, 0, diskid_offset, 4, diskbuf);
> +           dev->disk->partition = p;
> +           if (err)
> +             return grub_errno;
> +           partuuid = grub_xasprintf ("%02x%02x%02x%02x-%02x",
> +                                      diskbuf[3], diskbuf[2], diskbuf[1], 
> diskbuf[0],
> +                                      p->number + 1); /* one based partition 
> number */
> +         }
> +       else if (!grub_strcmp (p->partmap->name, "gpt"))
> +         {
> +           const int guid_offset = 16; /* location in entry */
> +           dev->disk->partition = p->parent;
> +           /* little-endian 16-byte EFI partition GUID */
> +           err = grub_disk_read (dev->disk, p->offset, p->index + 
> guid_offset, 16, diskbuf);
> +           dev->disk->partition = p;
> +           if (err)
> +             return grub_errno;
> +           partuuid = grub_xasprintf 
> ("%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
> +                                      diskbuf[3], diskbuf[2], diskbuf[1], 
> diskbuf[0],
> +                                      diskbuf[5], diskbuf[4],
> +                                      diskbuf[7], diskbuf[6],
> +                                      diskbuf[8], diskbuf[9],
> +                                      diskbuf[10], diskbuf[11], diskbuf[12], 
> diskbuf[13], diskbuf[14], diskbuf[15]);
> +         }
> +       else
> +         return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
> +                            N_("partition map %s does not support partition 
> UUIDs"),
> +                            dev->disk->partition->partmap->name);
> +     }
> +      else
> +     partuuid = grub_strdup (""); /* a freeable empty string */
> +
> +      if (state[0].set)
> +     grub_env_set (state[0].arg, partuuid);
> +      else
> +     grub_printf ("%s", partuuid);
> +      grub_free (partuuid);
> +      grub_device_close (dev);
> +      return GRUB_ERR_NONE;
> +    }
>    grub_device_close (dev);
>    return grub_error (GRUB_ERR_BAD_ARGUMENT, "unrecognised target");
>  }
>