On 05/12/2012 06:49 AM, Seth Jennings wrote:
> On 05/11/2012 02:29 PM, Konrad Rzeszutek Wilk wrote:
>
>>> At least, zram is also primary user and it also has such mess
>>> although it's not severe than zcache. zram->table[index].handle
>>> sometime has real (void*) handle, sometime (struct page*).
>>
>> Yikes. Yeah that needs to be fixed.
>>
>
>
> How about this (untested)? Changes to zram_bvec_write() are a little
> hard to make out in this format. There are a couple of checkpatch fixes
> (two split line strings) and an unused variable store_offset removal mixed
> in too. If this patch is good, I'll break them up for official submission
> after I test.
>
> diff --git a/drivers/staging/zram/zram_drv.h b/drivers/staging/zram/zram_drv.h
> index fbe8ac9..10dcd99 100644
> --- a/drivers/staging/zram/zram_drv.h
> +++ b/drivers/staging/zram/zram_drv.h
> @@ -81,7 +81,10 @@ enum zram_pageflags {
>
> /* Allocated for each disk page */
> struct table {
> - void *handle;
> + union {
> + void *handle; /* compressible */
> + struct page *page; /* incompressible */
You read my mind. That's exactly same idea with my patch which queued up to my tree.
But there is still problem.
zram has like this code
void *handle = zram->table[index].handle;
if (!handle) {
}
zram->table[index].handle = NULL;
It assume handle's size is greater than or equal to sizeof(struct page*)) for union working.
But we can't make sure handle's size.
If Nitin confirm this, too, the problem would be easy to fix.
--
Kind regards,
Minchan Kim
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