[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20090415081259.GB11054@liondog.tnic>
Date: Wed, 15 Apr 2009 10:13:00 +0200
From: Borislav Petkov <petkovbb@...glemail.com>
To: FUJITA Tomonori <fujita.tomonori@....ntt.co.jp>
Cc: tj@...nel.org, bharrosh@...asas.com,
James.Bottomley@...senpartnership.com, linux-scsi@...r.kernel.org,
axboe@...nel.dk, bzolnier@...il.com, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 14/17] scsi: replace custom rq mapping with
blk_rq_map_kern_sgl()
Hi,
On Wed, Apr 15, 2009 at 04:48:35PM +0900, FUJITA Tomonori wrote:
[..]
> I have some comments.
>
>
> > diff --git a/drivers/ide/ide-cd.c b/drivers/ide/ide-cd.c
> > index 35d0973..82c9339 100644
> > --- a/drivers/ide/ide-cd.c
> > +++ b/drivers/ide/ide-cd.c
> > @@ -206,32 +206,21 @@ static void cdrom_analyze_sense_data(ide_drive_t *drive,
> > ide_cd_log_error(drive->name, failed_command, sense);
> > }
> >
> > -static void cdrom_queue_request_sense(ide_drive_t *drive, void *sense,
> > - struct request *failed_command)
> > +static struct request *ide_cd_prep_sense(ide_drive_t *drive)
> > {
> > struct cdrom_info *info = drive->driver_data;
> > - struct request *rq = &drive->request_sense_rq;
> > - struct bio *bio = &drive->request_sense_bio;
> > - struct bio_vec *bvec = drive->request_sense_bvec;
> > - unsigned int bvec_len = ARRAY_SIZE(drive->request_sense_bvec);
> > - unsigned sense_len = 18;
> > - int error;
> > + void *sense = &info->sense_data;
> > + unsigned sense_len = sizeof(struct request_sense);
> > + struct request *rq;
> >
> > ide_debug_log(IDE_DBG_SENSE, "enter");
> >
> > - if (sense == NULL) {
> > - sense = &info->sense_data;
> > - sense_len = sizeof(struct request_sense);
> > - }
> > -
> > memset(sense, 0, sense_len);
> >
> > - /* stuff the sense request in front of our current request */
> > - blk_rq_init(NULL, rq);
> > + rq = blk_get_request(drive->queue, 0, __GFP_WAIT);
> >
> > - error = blk_rq_map_kern_prealloc(drive->queue, rq, bio, bvec, bvec_len,
> > - sense, sense_len, true);
> > - BUG_ON(error);
> > + if (blk_rq_map_kern(drive->queue, rq, sense, sense_len, __GFP_WAIT))
> > + return NULL;
> >
> > rq->rq_disk = info->disk;
> >
> > @@ -241,18 +230,17 @@ static void cdrom_queue_request_sense(ide_drive_t *drive, void *sense,
> > rq->cmd_type = REQ_TYPE_SENSE;
> > rq->cmd_flags |= REQ_PREEMPT;
> >
> > - /* NOTE! Save the failed command in "rq->special" */
> > - rq->special = (void *)failed_command;
> > -
> > - if (failed_command)
> > - ide_debug_log(IDE_DBG_SENSE, "failed_cmd: 0x%x",
> > - failed_command->cmd[0]);
> > + return rq;
> > +}
> >
> > - drive->hwif->rq = NULL;
> > +static void ide_cd_queue_rq_sense(ide_drive_t *drive)
> > +{
> > + BUG_ON(!drive->rq_sense);
> >
> > - elv_add_request(drive->queue, rq, ELEVATOR_INSERT_FRONT, 0);
> > + elv_add_request(drive->queue, drive->rq_sense, ELEVATOR_INSERT_FRONT, 0);
> > }
> >
> > +
> > static void ide_cd_complete_failed_rq(ide_drive_t *drive, struct request *rq)
> > {
> > /*
> > @@ -440,7 +428,7 @@ static int cdrom_decode_status(ide_drive_t *drive, u8 stat)
> >
> > /* if we got a CHECK_CONDITION status, queue a request sense command */
> > if (stat & ATA_ERR)
> > - cdrom_queue_request_sense(drive, NULL, NULL);
> > + ide_cd_queue_rq_sense(drive);
> > return 1;
> >
> > end_request:
> > @@ -454,7 +442,7 @@ end_request:
> >
> > hwif->rq = NULL;
> >
> > - cdrom_queue_request_sense(drive, rq->sense, rq);
> > + ide_cd_queue_rq_sense(drive);
> > return 1;
> > } else
> > return 2;
> > @@ -788,6 +776,10 @@ out_end:
> >
> > ide_complete_rq(drive, uptodate ? 0 : -EIO, nsectors << 9);
> >
> > + /* our sense buffer got used, reset it the next time around. */
> > + if (sense)
> > + drive->rq_sense = NULL;
>
> Needs to call blk_put_request() here?
No, because this is done by ide_complete_rq() above. Otherwise I'd be
ending the sense request even it didn't get used. This way, I only use
it if I call ide_cd_queue_rq_sense() from which cdrom_decode_status().
> I guess that we also need to call blk_put_request() when ide_drive_s
> is freed.
That we need to do, thanks. Will update accordingly.
> > +
> > if (sense && rc == 2)
> > ide_error(drive, "request sense failure", stat);
> > }
> > @@ -901,6 +893,25 @@ static ide_startstop_t ide_cd_do_request(ide_drive_t *drive, struct request *rq,
> > goto out_end;
> > }
> >
> > + /*
> > + * prepare request sense if it got used with the last rq
> > + */
> > + if (!drive->rq_sense) {
> > + drive->rq_sense = ide_cd_prep_sense(drive);
> > + if (!drive->rq_sense) {
> > + printk(KERN_ERR "%s: error prepping sense request!\n",
> > + drive->name);
> > + return ide_stopped;
> > + }
> > + }
> > +
> > + /*
> > + * save the current request in case we'll be queueing a sense rq
> > + * afterwards due to its potential failure.
> > + */
> > + if (!blk_sense_request(rq))
> > + drive->rq_sense->special = (void *)rq;
> > +
> > memset(&cmd, 0, sizeof(cmd));
> >
> > if (rq_data_dir(rq))
> > diff --git a/include/linux/ide.h b/include/linux/ide.h
> > index c942533..4c2d310 100644
> > --- a/include/linux/ide.h
> > +++ b/include/linux/ide.h
> > @@ -605,6 +605,9 @@ struct ide_drive_s {
> > struct request request_sense_rq;
> > struct bio request_sense_bio;
> > struct bio_vec request_sense_bvec[2];
>
> We can remove the above, right?
id-atapi uses them too, see
http://git.kernel.org/?p=linux/kernel/git/tj/misc.git;a=commitdiff;h=9ac15840a6e5bf1fa6dce293484cb7aba4d078bb
They can go after I've converted ide-floppy and ide-tape to the same
sense handling as ide-cd. I'm on it...
--
Regards/Gruss,
Boris.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists