linux-kernel - Re: libata & no PCI: dma_[un]map

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]

Date:	Tue, 5 Jun 2007 09:56:08 -0400
From:	Jeff Garzik <jeff@...zik.org>
To:	Alan Cox <alan@...rguk.ukuu.org.uk>
Cc:	Christoph Hellwig <hch@...radead.org>,
	David Miller <davem@...emloft.net>, mroos@...ux.ee,
	linux-kernel@...r.kernel.org
Subject: Re: libata & no PCI: dma_[un]map_single undefined

On Tue, Jun 05, 2007 at 12:22:18PM +0100, Alan Cox wrote:
> > NAK
> > 
> > We have generic devices and generic DMA mapping.  libata already uses
> > the generic stuff.  Now fix the platform...
> 
> Nice theory but your generic helpers rely on the map functions working
> even for generic hardware that doesn't need them, so at the very least
> there is some clean up required.

Sure there is some clean up needed -- on the arch side.

Even !PCI dma_xxx wrappers that do nothing more than return a dma
mapping error are a valid platform implementation.

Even !HAS_DMA (s/390?) arches should be using the aforementioned
return-error wrappers, mimicing the implementation of PCI functions
in linux/pci.h for the !PCI case.

libata core for DMA mapping is already generic enough such that, #ifdefs
are not needed in the code.

OTOH.....  further work in libata _is_ need for I/O accessors, to
isolate those from the core code.

	Jeff

-
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/