Problem: 51MB partition max size on jffs2

Thomas Gleixner tglx at linutronix.de
Wed Dec 4 18:20:44 EST 2002


On Thursday 05 December 2002 00:08, Ken Offer wrote:
> On Wednesday, December 4, 2002, at 04:02  PM, Thomas Gleixner wrote:
> > On Wednesday 04 December 2002 23:00, Ken Offer wrote:
> >> On Wednesday, December 4, 2002, at 11:47  AM, Thomas Gleixner wrote:
> >>> Latest CVS code ?
> >>
> >> I tried it with an older version (circa 20020819) and the latest code
> >> (20021202).  Same result.  I am going to try the change Dave Ellis
> >> <DGE at sixnetio.com> suggested.
> >
> > Strange. Could you please tell me, what output the latest CVS code
> > produces
>
> Well, I was getting a mount failure.  There wasn't much info other than
> that.  If you look in the latest (20021202) jffs2 build.c file, you can
> see if the kmalloc of c->blocks fails in jffs2_do_mount_fs, no debug
> message is printed.  Only a non-mem error is returned.  That is
> consistent with what I was seeing, even with the highest verbosity
> debugging on.
>
> I made the change to use vmalloc/vfree for c->blocks and that seemd to
> fix the problem.  kmalloc is indeed limited to 128KB.  Of course, I
> made the change to the 20020819 code.  I'll try the vmalloc change with
> the latest CVS code as well and see how that holds up.
Please wait. 
Could you please verify, if the code in fs. c does, what it should do ?

int jffs2_do_fill_super(struct super_block *sb, void *data, int silent)
{
SNIP
	c->flash_size = c->mtd->size;
	/* 
	 * Check, if we have to concatenate physical blocks to larger virtual blocks
	 * to reduce the memorysize for c->blocks. (kmalloc allows max. 128K 
allocation)
	 */
	blocks = c->flash_size / c->mtd->erasesize;
	while ((blocks * sizeof (struct jffs2_eraseblock)) > (128 * 1024))
		blocks >>= 1;
	
	c->sector_size = c->flash_size / blocks;
	if (c->sector_size != c->mtd->erasesize)
		printk(KERN_INFO "jffs2: Erase block size too small (%dKiB). Using virtual 
blocks size (%dKiB) instead\n", 
			c->mtd->erasesize / 1024, c->sector_size / 1024);

This is processed before calling jffs2_do_mount_fs. There is calculated:

	c->nr_blocks = c->flash_size / c->sector_size;
	c->blocks = kmalloc(sizeof(struct jffs2_eraseblock) * c->nr_blocks, 
GFP_KERNEL);
	if (!c->blocks)
		return -ENOMEM;

So it should rely on the previous adjusted sectorsize.

-- 
Thomas
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