[linux-lvm] Re: raid 1 on a single disk

ashwin chaugule ashwin.chaugule at gmail.com
Sun Nov 14 19:02:53 UTC 2004

>Because your code, like your description, is an uncontrolled mess,

WHAT !!!!!

>Registers?  What registers? Do you mean "fields"?

yes i mean fields, my bad.

>This sounds like stuff you do in the driver , on receipt of your special
>request.  Is that so and how do you recognize it

by checking the MAJOR and MINOR num of my disk !!!!! ?

>Default interrupt handler? 

remember i said , i set a different intr. handler if its my disk !? 
well, after its handled there, i dont call end_request , simple.
mult_write is the default intr. handler for multiple writes ?
i set mult_write_withoutend as the handler, then after the handling is
done , i again set
mult_write as the handler.... this will call the end_request.

>or whether you only have one request hit the
>driver and when it hits you simply treat it twice

bingo !

>Probably because some stuff is returned to kernel pools and messes them
>up completely.

what stuff ? im not returning anything to any queue whatsoever !

>Because your code, like your description, is an uncontrolled mess,

about the code .. umm , maybe not , coz the write is duplicated alright ..
my description , a mess ?... nope , what im doing is really simple ,
as i stated in the very first mail , im doing something similar to
RAID 1 !! , what s so hard to understand in that ?
I also said , why im continuing with the IDE modifications inspite of
the RAID 1 drivers.


However, in my driver (modified IDE) I have to take care of the writes
and reads individualy.
The advantage here is that, i dont need to make 4 partitions of the
disk, one is good enough, and the remaining can be unallocated. I make
the write at fixed offsets into the unallocated space, and when read
is requested, I read em one by one, and check.


So now ( after im done with the read requests ) i have two options for them...
RAID 1 and the modified the IDE driver.


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