Re: [PATCH 3/3] ide-{cd,floppy}: do not map all cmds to an sg

Borislav Petkov
2009-03-10T06:08:53Z

Hi,

> If the mainline is broken sg fix can wait but to be honest I don't see much
> point in delaying it (it is an independent problem and the bugfix should be
> a completely safe one-liner).

--
From: Borislav Petkov <petkovbb@gmail.com>
Date: Tue, 10 Mar 2009 07:04:52 +0100
Subject: [PATCH] ide-floppy: do not map dataless cmds to an sg

since it fails the virt_to_page() translation check with DEBUG_VIRTUAL
enabled.

Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
---
drivers/ide/ide-atapi.c | 12 ++++++++++++
drivers/ide/ide-floppy.c | 6 ++++--
2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/drivers/ide/ide-atapi.c b/drivers/ide/ide-atapi.c
index a5596a6..11a680c 100644
--- a/drivers/ide/ide-atapi.c
+++ b/drivers/ide/ide-atapi.c
@@ -90,6 +90,12 @@ static void ide_queue_pc_head(ide_drive_t *drive, struct gendisk *disk,
rq->cmd_flags |= REQ_PREEMPT;
rq->buffer = (char *)pc;
rq->rq_disk = disk;
+
+ if (pc->req_xfer) {
+ rq->data = pc->buf;
+ rq->data_len = pc->req_xfer;
+ }
+
memcpy(rq->cmd, pc->c, 12);
if (drive->media == ide_tape)
rq->cmd[13] = REQ_IDETAPE_PC1;
@@ -112,6 +118,12 @@ int ide_queue_pc_tail(ide_drive_t *drive, struct gendisk *disk,
rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
rq->cmd_type = REQ_TYPE_SPECIAL;
rq->buffer = (char *)pc;
+
+ if (pc->req_xfer) {
+ rq->data = pc->buf;
+ rq->data_len = pc->req_xfer;
+ }
+
memcpy(rq->cmd, pc->c, 12);
if (drive->media == ide_tape)
rq->cmd[13] = REQ_IDETAPE_PC1;
diff --git a/drivers/ide/ide-floppy.c b/drivers/ide/ide-floppy.c
index 2f8f453..2b4868d 100644
--- a/drivers/ide/ide-floppy.c
+++ b/drivers/ide/ide-floppy.c
@@ -282,8 +282,10 @@ static ide_startstop_t ide_floppy_do_request(ide_drive_t *drive,

cmd.rq = rq;

- ide_init_sg_cmd(&cmd, pc->req_xfer);
- ide_map_sg(drive, &cmd);
+ if (blk_fs_request(rq) || pc->req_xfer) {
+ ide_init_sg_cmd(&cmd, pc->req_xfer);
+ ide_map_sg(drive, &cmd);
+ }

pc->rq = rq;

--
1.6.2

> From: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
> Subject: [PATCH] ide-cd: use scatterlists for PIO transfers (non-fs requests) (v2)
>
> Convert ide-cd to use scatterlists for PIO transfers and get rid of
> partial completions (except on error) also for non-fs requests.
>
> v2:
> Do not map dataless commands to an sg since it oopses on the virt_to_page()
> translation check when DEBUG_VIRTUAL is enabled. (from Borislav Petkov,
> reported/bisected-by Tetsuo Handa).
>
> Cc: Borislav Petkov <petkovbb@gmail.com>
> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Acked-by: Borislav Petkov <petkovbb@gmail.com>

--
Regards/Gruss,
Boris.