From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bartlomiej Zolnierkiewicz Subject: Re: [PATCH ide-dev-2.6] ide: ide_dma_intr oops fix Date: Thu, 3 Mar 2005 09:14:03 +0100 Message-ID: <58cb370e05030300145c554abe@mail.gmail.com> References: <20050303030318.GA25410@htj.dyndns.org> <20050303064925.GB19505@suse.de> <4226B54E.6020709@gmail.com> <58cb370e050303000478119a22@mail.gmail.com> <20050303080519.GE19505@suse.de> Reply-To: Bartlomiej Zolnierkiewicz Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Received: from wproxy.gmail.com ([64.233.184.200]:38827 "EHLO wproxy.gmail.com") by vger.kernel.org with ESMTP id S261571AbVCCIOH (ORCPT ); Thu, 3 Mar 2005 03:14:07 -0500 Received: by wproxy.gmail.com with SMTP id 68so483966wra for ; Thu, 03 Mar 2005 00:14:05 -0800 (PST) In-Reply-To: <20050303080519.GE19505@suse.de> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Jens Axboe Cc: Tejun Heo , linux-kernel@vger.kernel.org, linux-ide@vger.kernel.org On Thu, 3 Mar 2005 09:05:19 +0100, Jens Axboe wrote: > On Thu, Mar 03 2005, Bartlomiej Zolnierkiewicz wrote: > > On Thu, 03 Mar 2005 15:57:18 +0900, Tejun Heo wrote: > > > Hello, Jens. > > > > > > Jens Axboe wrote: > > > > On Thu, Mar 03 2005, Tejun Heo wrote: > > > > > > > >> Hello, Bartlomiej. > > > >> > > > >> This patch fixes ide_dma_intr() oops which occurs for TASKFILE ioctl > > > >>using DMA dataphses. This is against the latest ide-dev-2.6 tree + > > > >>all your recent 9 patches. > > > >> > > > >> Signed-off-by: Tejun Heo > > > >> > > > >>Index: linux-taskfile-ng/drivers/ide/ide-dma.c > > > >>=================================================================== > > > >>--- linux-taskfile-ng.orig/drivers/ide/ide-dma.c 2005-03-03 11:59:16.485582413 +0900 > > > >>+++ linux-taskfile-ng/drivers/ide/ide-dma.c 2005-03-03 12:00:07.753376048 +0900 > > > >>@@ -175,10 +175,14 @@ ide_startstop_t ide_dma_intr (ide_drive_ > > > >> if (OK_STAT(stat,DRIVE_READY,drive->bad_wstat|DRQ_STAT)) { > > > >> if (!dma_stat) { > > > >> struct request *rq = HWGROUP(drive)->rq; > > > >>- ide_driver_t *drv; > > > >> > > > >>- drv = *(ide_driver_t **)rq->rq_disk->private_data;; > > > >>- drv->end_request(drive, 1, rq->nr_sectors); > > > >>+ if (rq->rq_disk) { > > > >>+ ide_driver_t *drv; > > > >>+ > > > >>+ drv = *(ide_driver_t **)rq->rq_disk->private_data;; > > > >>+ drv->end_request(drive, 1, rq->nr_sectors); > > > >>+ } else > > > >>+ ide_end_request(drive, 1, rq->nr_sectors); > > > >> return ide_stopped; > > > >> } > > > >> printk(KERN_ERR "%s: dma_intr: bad DMA status (dma_stat=%x)\n", > > > > > > > > Why not just set rq_disk for taskfile requests as well, seems a lot > > > > cleaner than special casing the end_request handling. > > > > > > Just because other places were fixed this way and the whole drive > > > command issue/completion codes are just about to be restructured. Above > > > code will go away soon. Please consider it a quick fix. > > > > > > Thanks. > > > > Because struct gendisk is now allocated by device drivers (like in SCSI > > subsystem) rq_disk can't be set for REQ_DRIVE_TASKFILE requests > > (for some requests it can be set but better to keep it consistent). > > Seems cleaner to store the driver in the drive structure then, no > special casing needed. This can't be done *correctly* with driver model support, that is why SCSI does the same trick. There were three incremental patch series, all sent to linux-{ide,kernel} (all patches except the final one are now in ide-dev-2.6), to convert IDE device drivers to driver model.