On Sat, Oct 20, 2001 at 09:48:31PM -0700, Chuck Silvers wrote:
> ok, try the attached patch.

it certainly seems to have changed things.

cdparanoia doesn't panic the kernel, and it gives me a list of tracks.

i'll be playing with it more, but i think you've fixed it for my issues.

thanx muchly.

> 
> -Chuck
> 
> 
> On Sat, Oct 20, 2001 at 01:27:51PM -0500, Bob Nestor wrote:
> > >From what I've seen the Partition Map is the same on disk and CD.  It is 
> > stored in entrries that are 512 bytes in length.  There can be alternate 
> > entries in the Partition Map that are used for accessing the CD in 2K 
> > blocks, but those entries still appear to be 512 bytes in length 
> > themselves.  From this I assume the Partition Map is always processed as 
> > if it were composed of entries each containing 512 bytes, but an entry 
> > may describe a Partition that should be processed as 2K sized blocks.
> > 
> > I've got some utilities that I used to dump various Partition Maps from 
> > different devices; SCSI disks, IDE disks, and CDs.  If anyone would like 
> > them or the dumps I've gotten from my devices I'd be happy to provide 
> > them.
> > 
> > Hope this helps,
> > -bob
> > 
> > On 10/20/01 1:19 PM, Chuck Silvers (chuq@chuq.com) wrote:
> > 
> > >no one answered my question, so I don't know what the right fix is yet.
> > >
> > >-Chuck
> > >
> > >
> > >On Sat, Oct 20, 2001 at 11:05:46AM -0400, Jim Mercer wrote:
> > >> On Wed, Oct 03, 2001 at 11:28:14PM -0700, Chuck Silvers wrote:
> > >> > well the problem is pretty obvious.  mac68k/disksubr.c has:
> > >> 
> > >> did we ever see a solution to this?
> > >> 
> > >> > 
> > >> > #define NUM_PARTS 32
> > >> > 
> > >> > char *
> > >> > readdisklabel(dev, strat, lp, osdep)
> > >> > ...
> > >> > {
> > >> > 	...
> > >> > 	bp = geteblk((int)lp->d_secsize * (NUM_PARTS + 1));
> > >> > 	...
> > >> > }
> > >> > 
> > >> > 
> > >> > for a cdrom, lp->d_secsize is going to be 2k, so readdisklabel()
> > >> > will try to allocate a buffer of size 2k * 33 = 66k, which is larger
> > >> > than MAXBSIZE (which is 64k).
> > >> > 
> > >> > I'm guessing that readdisklabel() is really assuming that lp->d_secsize
> > >> > is 512, in which case this would work out fine.  if the mac partition map
> > >> > records are stored consectively on disk (rather than 1 entry per sector
> > >> > as the code currently assumes) then we should be able to replace all of
> > >> > the occuraces of "lp->d_secsize" with "512", and then round the argument
> > >> > of geteblk() up to a multiple of lp->d_secsize.
> > >> > 
> > >> > could someone that has a cd with a mac partition table on it
> > >> > check to see whether the partition map records are packed or
> > >> > 1 entry per sector?
> > >> > 
> > >> > -Chuck
> > >> > 
> > >> > 
> > >> > On Wed, Oct 03, 2001 at 12:45:51PM -0400, Jim Mercer wrote:
> > >> > > On Tue, Oct 02, 2001 at 09:20:58PM -0700, Chuck Silvers wrote:
> > >> > > > what is the stack trace when it panics like this?
> > >> > > > (type "t" in ddb)
> > >> > > 
> > >> > > sorry, i don't have a serial console, so this is by hand, if you need 
> > the
> > >> > > specific numbers, i can get them by crashing it again.
> > >> > > 
> > >> > > panic: allocbuf: buffer larger than MAXBSIZE requested
> > >> > > Stopped in pid 186 (cdparanoia) at _spu_Debugger+0x6:  unlk  a6
> > >> > > db> t
> > >> > > _cpu_Debugger(
> > >> > > _panic(
> > >> > > _allocbuf(
> > >> > > _geteblk(
> > >> > > _readdisk(
> > >> > > _cdgetdisklabel(
> > >> > > _cdopen(
> > >> > > _spec_open(
> > >> > > _VOP_OPEN(
> > >> > > _vn_open(
> > >> > > _sys_open(
> > >> > > _syscall(
> > >> > > _trap(
> > >> > > 
> > >> > > 
> > >> > > > 
> > >> > > > -Chuck
> > >> > > > 
> > >> > > > 
> > >> > > > On Tue, Oct 02, 2001 at 03:15:15PM -0400, Jim Mercer wrote:
> > >> > > > > 
> > >> > > > > i've tried this with the current-20010915 SBC kernel and i have the
> > >> > > > > current-20010915 userland.
> > >> > > > > 
> > >> > > > > i built and installed cdparanoia.
> > >> > > > > 
> > >> > > > > when i run it to query the drive, i get a panic/break to debugger:
> > >> > > > > 
> > >> > > > > panic: allocbuf: buffer larger than MAXBSIZE requested
> > >> > > > > stopped in pid 16209 (cdparanoia) at _cpu_Debugger+0x6: unlk  a6
> > >> > > > > 
> > >> > > > > note: this same thing happened using binary package versions of 
> > other
> > >> > > > > cdrom/audio tools on 1.5.0, 1.5.1 and 1.5.2.
> > >> > > > > 
> > >> > > > > hardware is:
> > >> > > > > 
> > >> > > > > Mac LC575, 36M, upgraded to full 68040
> > >> > > > > 
> > >> > > > > CD is Neil Young.  8^)
> > >> > > > > 
> > >> > > > > -- 
> > >> > > > > [ Jim Mercer        jim@reptiles.org         +1 416 410-5633 ]
> > >> > > > > [ Now with more and longer words for your reading enjoyment. ]
> > >> > > 
> > >> > > -- 
> > >> > > [ Jim Mercer        jim@reptiles.org         +1 416 410-5633 ]
> > >> > > [ Now with more and longer words for your reading enjoyment. ]
> > >> 
> > >> -- 
> > >> [ Jim Mercer        jim@reptiles.org         +1 416 410-5633 ]
> > >> [ Now with more and longer words for your reading enjoyment. ]
> > >

> Index: arch/mac68k/mac68k/disksubr.c
> ===================================================================
> RCS file: /cvsroot/syssrc/sys/arch/mac68k/mac68k/disksubr.c,v
> retrieving revision 1.38
> diff -u -r1.38 disksubr.c
> --- arch/mac68k/mac68k/disksubr.c	2001/07/14 07:38:31	1.38
> +++ arch/mac68k/mac68k/disksubr.c	2001/10/21 04:45:55
> @@ -277,7 +277,7 @@
>  	*match = (-1);
>  
>  	/* the Macintosh partition table starts at sector #1 */
> -	part = (struct part_map_entry *)(dlbuf + lp->d_secsize);
> +	part = (struct part_map_entry *)(dlbuf + DEV_BSIZE);
>  
>  	/* Fill in standard partitions */
>  	lp->d_npartitions = RAW_PART + 1;
> @@ -400,8 +400,8 @@
>  	msg = NULL;
>  
>  	blk_start = (struct disklabel *)dlbuf;
> -	blk_end = (struct disklabel *)(dlbuf + NUM_PARTS * 
> -	    lp->d_secsize - sizeof(struct disklabel));
> +	blk_end = (struct disklabel *)(dlbuf + (NUM_PARTS << DEV_BSHIFT) -
> +	    sizeof(struct disklabel));
>  
>  	for (dlp = blk_start; dlp <= blk_end; 
>  	     dlp = (struct disklabel *)((char *)dlp + sizeof(long))) {
> @@ -435,6 +435,7 @@
>  {
>  	struct buf *bp;
>  	char *msg;
> +	int size;
>  
>  	if (lp->d_secperunit == 0)
>  		lp->d_secperunit = 0x1fffffff;
> @@ -443,17 +444,20 @@
>  		return msg = "Zero secpercyl";
>  
>  	msg = NULL;
> +
>  	/* 
>  	 * Read in the first #(NUM_PARTS + 1) blocks of the disk.
>  	 * The native Macintosh partition table starts at 
>  	 * sector #1, but we want #0 too for the BSD label.
>  	 */
> -	bp = geteblk((int)lp->d_secsize * (NUM_PARTS + 1));
> +
> +	size = roundup((NUM_PARTS + 1) << DEV_BSHIFT, lp->d_secsize);
> +	bp = geteblk(size);
>  
>  	bp->b_dev = dev;
>  	bp->b_blkno = 0;
>  	bp->b_resid = 0;
> -	bp->b_bcount = lp->d_secsize * (NUM_PARTS + 1);
> +	bp->b_bcount = size;
>  	bp->b_flags |= B_READ;
>  	bp->b_cylinder = 1 / lp->d_secpercyl;
>  	(*strat)(bp);


-- 
[ Jim Mercer        jim@reptiles.org         +1 416 410-5633 ]
[ Now with more and longer words for your reading enjoyment. ]