Re: Problem: 51MB partition max size on jffs2

Ken Offer
2002-12-05T17:22:53Z

On Wednesday, December 4, 2002, at 05:20 PM, Thomas Gleixner wrote:

> 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@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.

Ok, I switched back to the latest CVS and tried to mount the partition.
No luck, even with a 32MB partition. I get:

mount -t jffs2 /dev/mtdblock1 /mnt/jffs
mount: /dev/mtdblock1 is not a valid block device

I have tried the latest CVS with both the "vmalloc c->blocks" change
and without. In both cases mount fails the same way. I turned up
debugging all the way for jffs2 and mtd but no messages were printed to
/var/log/messages. Guess I need to scour the jffs2 code and add some
more printks...

So... I don't know yet if the above code is working or not. I need to
find out why mount doesn't like /dev/mtdblock1 with the latest CVS code
(but DOES like it for the 20020819 code).

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| Ken Offer koffer@arlut.utexas.edu ARL:UT |
| Office: 512-835-3859 Fax: 512-835-3259 |
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