Re: [PATCH] [46/48] Suspend2 2.1.9.8 for 2.6.12: 622-swapwriter.patch

Nigel Cunningham
2005-07-07T21:16:46Z

Hi.

On Thu, 2005-07-07 at 23:32, Pekka Enberg wrote:
> Hi Nigel,
>
> > diff -ruNp 623-generic-block-io.patch-old/kernel/power/suspend_block_io.c 623-generic-block-io.patch-new/kernel/power/suspend_block_io.c
> > --- 623-generic-block-io.patch-old/kernel/power/suspend_block_io.c 1970-01-01 10:00:00.000000000 +1000
> > +++ 623-generic-block-io.patch-new/kernel/power/suspend_block_io.c 2005-07-05 23:48:59.000000000 +1000
> > @@ -0,0 +1,817 @@
> > +struct io_info {
> > + struct bio * sys_struct;
> > + long block[PAGE_SIZE/512];
>
> Aah, but for this you should use block_size(io_info->dev) instead. No
> need to mess with sector sizes. Why is this long by the way?
> PAGE_SIZE/512 is block size in bytes.

No... it's the maximum number of blocks per page. Depending upon how
the user has set the blocksize when they created the filesystem (in the
case of filesystems), the number of blocks we use per page might be 1,
2, 4 or 8.

It's long because a sector number is stored in it.

Regards,

Nigel

> > + struct page * buffer_page;
> > + struct page * data_page;
> > + unsigned long flags;
> > + struct block_device * dev;
> > + struct list_head list;
> > + int readahead_index;
> > + struct work_struct work;
> > +};
>
> Pekka
>
--
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