From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx1.redhat.com (mx1.redhat.com [172.16.48.31]) by int-mx1.corp.redhat.com (8.11.6/8.11.6) with ESMTP id iAEJ2sr16720 for ; Sun, 14 Nov 2004 14:02:54 -0500 Received: from rproxy.gmail.com (rproxy.gmail.com [64.233.170.207]) by mx1.redhat.com (8.12.11/8.12.11) with ESMTP id iAEJ2sFw021640 for ; Sun, 14 Nov 2004 14:02:54 -0500 Received: by rproxy.gmail.com with SMTP id f1so476702rne for ; Sun, 14 Nov 2004 11:02:53 -0800 (PST) Message-ID: <89af10f904111411023d1169bc@mail.gmail.com> Date: Mon, 15 Nov 2004 00:32:53 +0530 From: ashwin chaugule Subject: Re: [linux-lvm] Re: raid 1 on a single disk In-Reply-To: Mime-Version: 1.0 Content-Transfer-Encoding: 7bit References: <89af10f90411130217467c439@mail.gmail.com> <89af10f90411130241e20e2c2@mail.gmail.com> <20041113211324.GA13108@dragonhold.org> <87f94c37041113140053f493b0@mail.gmail.com> <89af10f904111321441f2a3a1e@mail.gmail.com> <04sj62-uei.ln1@news.it.uc3m.es> <89af10f90411140941260b4b4b@mail.gmail.com> Reply-To: ashwin chaugule , LVM general discussion and development List-Id: LVM general discussion and development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , List-Id: Content-Type: text/plain; charset="us-ascii" To: LVM general discussion and development >Because your code, like your description, is an uncontrolled mess, >probably. 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. eg. 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, >probably. 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. --snipped-- 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. --snipped-- So now ( after im done with the read requests ) i have two options for them... RAID 1 and the modified the IDE driver. Ashwin