Re: [OpenBIOS] [RFC PATCH] ppc correctly replace &device; and &partition;

[Stefan Assmann]

Laurent Vivier wrote:
> > Le 3 févr. 09 à 14:27, Stefan Assmann a écrit :
> > > Subject: ppc correctly replace &device; and &partition;
> > >
> > > This patch correctly replaces the variables &device; and &partition;
> > > with firmware values thus allowing to boot from different partitions.
> > >
> > > Signed-off-by: Stefan Assmann
> > > Index: arch/ppc/qemu/main.c
> > >
> > > --- arch/ppc/qemu/main.c	(revision 439)
> > > +++ arch/ppc/qemu/main.c	(working copy)
> > > @@ -154,9 +154,9 @@
> > > static void
> > > try_bootinfo(const char *path)
> > > {
> > > int fd;
> > > char tagbuf[256], bootscript[256], c, *left, *right;
> > > int len, tag, taglen, script, scriptlen;
> > >
> > > int fd, len, tag, taglen, script, scriptlen;
> > >
> > > char tagbuf[256], bootscript[256], c;
> > >
> > > char *buf, *partition;
> > >
> > > snprintf(bootscript, sizeof(bootscript), "%s,ppc\bootinfo.txt",
> > >
> > > path);
> > >     ELF_DPRINTF("Trying %s\n", bootscript);
> > > @@ -195,22 +195,33 @@
> > >             bootscript[scriptlen++] = c;
> > >         }
> > >     } while (1);
> > >
> > > ELF_DPRINTF("got bootscript %s\n", bootscript);
> > >
> > > // Replace &device;: with original path
> > >
> > > push_str(bootscript);
> > >
> > > PUSH('&');
> > >
> > > fword("left-split");
> > >
> > > fword("2swap");
> > >
> > > PUSH(':');
> > >
> > > fword("left-split");
> > >
> > > fword("2drop");
> > >
> > > right = pop_fstr_copy();
> > >
> > > left = pop_fstr_copy();
> > >
> > > while (right[0] != '\' && right[0] != '\0')
> > >
> > > right++;
> > >
> > > snprintf(bootscript, sizeof(bootscript), "%s%s,%s", left, path,
> > >
> > > right);
> > > /* replace &device; and &partition; */
> > > if ( (buf =  strstr(bootscript, (const char *) "&device;")) !=
> > >
> > > NULL ) {
> > >        buf[0] = '\0';
> > >    buf += strlen("&device;");
> > >        snprintf(bootscript, sizeof(bootscript), "%s%s%s",  
> > >
> > > bootscript, path, buf);
> >
> > what happens if strlen(path) > strlen("&device;") ?
> > moreover device is not path, but path is "device:partition"
> > > }
> > > if ( (partition = strchr(path, ':')) != NULL ) {
> > >    *partition = '\0';
> > >    partition++;
> > >    if ( (buf = strstr(bootscript, (const char *)  
> > >
> > > "&partition;")) != NULL ) {
> > >        *buf = '\0';
> > >        buf += strlen("&partition;");
> > >        snprintf(bootscript, sizeof(bootscript), "%s%s%s",  
> > >
> > > bootscript, partition, buf);
> >
> > what happens if strlen(partition) > strlen("&partition;") ?
> > >    } else {
> > >        /* FIXME: allow booting of SUSE media with following  
> > >
> > > layout (fails without this workaround)
> > >         * Number  Start  End     Size    File system   
> > >
> > > Name        Flags
> > >         * 1      512B   1535B   1024B                 
> > >
> > > Apple       , , , , , , , , , , , , type=Apple_partition_map
> > >         * 2      8192B  4126MB  4126MB                
> > >
> > > SU1110.001  , , , , , , , , , , , , type=Apple_HFS
> > >         */
> > >        if ( (buf = strstr(bootscript, (const char *) "1,\ 
> > >
> > > \suseboot\yaboot.ibm")) != NULL ) {
> >
> > what it is wrong here is we try to read a file from partition 1 which  
> > is the partition map...
> > I guess we should write a "modules/iso9660-parts.c" to override this  
> > (as macintosh CD are hybrid: ISO9660 and HFS).
>
> Something like that seems to work:
> Index: openbios-devel/modules/disk-label.c
>
> --- openbios-devel.orig/modules/disk-label.c	2009-02-04 12:51:53.000000000 +0100
> +++ openbios-devel/modules/disk-label.c	2009-02-04 12:56:51.000000000 +0100
> @@ -78,6 +78,19 @@
>    	}
>    }
>    /* try to see if there is a filesystem without partition */
> PUSH_ih( my_self() );
> selfword("find-filesystem");
> ph = POP_ph();
> if( ph ) {
> push_str( filename );
> PUSH_ph( ph );
> fword("interpose");
>        success = 1;
>            goto out;
> }
> /* find partition handler */
>  seek_io( fd, 0 );
>  if( read_io(fd, block0, sizeof(block0)) != sizeof(block0) )

Nice! I'll try that and post an updated patch.
>

Stefan