linux-kernel - Re: [PATCH 19/19] ide: use PIO/MMIO operations directly where possible

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <58cb370e0701120619v27ca51dek48154136e54defd5@mail.gmail.com>
Date:	Fri, 12 Jan 2007 15:19:43 +0100
From:	"Bartlomiej Zolnierkiewicz" <bzolnier@...il.com>
To:	Alan <alan@...rguk.ukuu.org.uk>
Cc:	linux-ide@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 19/19] ide: use PIO/MMIO operations directly where possible

On 1/12/07, Alan <alan@...rguk.ukuu.org.uk> wrote:
> On Fri, 12 Jan 2007 05:28:07 +0100
> Bartlomiej Zolnierkiewicz <bzolnier@...il.com> wrote:
>
> > [PATCH] ide: use PIO/MMIO operations directly where possible
> >
> > This results in smaller/faster/simpler code and allows future optimizations.
> > Also remove no longer needed ide[_mm]_{inl,outl}() and ide_hwif_t.{INL,OUTL}.
> >
> > Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@...il.com>
>
> > --- a.orig/drivers/ide/ide-dma.c
> > +++ a/drivers/ide/ide-dma.c
> > @@ -565,7 +565,10 @@ int ide_dma_setup(ide_drive_t *drive)
> >       }
> >
> >       /* PRD table */
> > -     hwif->OUTL(hwif->dmatable_dma, hwif->dma_prdtable);
> > +     if (hwif->mmio == 2)
> > +             writel(hwif->dmatable_dma, (void __iomem *)hwif->dma_prdtable);
> > +     else
> > +             outl(hwif->dmatable_dma, hwif->dma_prdtable);
>
>
> This should simply be if (hwif->mmio)
>
> mmio = 1 is still used by some amiga and other oddments and indicates
> mmio in old form. I don't think this causes a bug as they don't use the
> DMA layer, but its a bug waiting to happen if the mmio==1 case doesn't
> get handled correctly or BUG()

mmio = 1 isn't used in the current IDE code and we have BUG_ON()
for it in ide.c:ide_hwif_request_regions() so the above change is safe.

Anyway thanks for bringing mmio = 1 issue - it can be converted
to flag now (will let us avoid similar confusions in the future).

Bart
-
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/