From: Christoph Hellwig <hch@lst.de>
To: Thomas Bogendoerfer <tbogendoerfer@suse.de>
Cc: Christoph Hellwig <hch@lst.de>,
"David S. Miller" <davem@davemloft.net>,
linux-mips@vger.kernel.org, netdev@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/4] net: sgi: ioc3-eth: don't abuse dma_direct_* calls
Date: Wed, 30 Oct 2019 23:38:18 +0100 [thread overview]
Message-ID: <20191030223818.GA23807@lst.de> (raw)
In-Reply-To: <20191030230549.ef9b99b5d36b0a818d904eee@suse.de>
On Wed, Oct 30, 2019 at 11:05:49PM +0100, Thomas Bogendoerfer wrote:
> On Wed, 30 Oct 2019 14:12:30 -0700
> Christoph Hellwig <hch@lst.de> wrote:
>
> > dma_direct_ is a low-level API that must never be used by drivers
> > directly. Switch to use the proper DMA API instead.
>
> is the 4kb/16kb alignment still guaranteed ? If not how is the way
> to get such an alignment ?
The DMA API gives you page aligned memory. dma_direct doesn't give you
any gurantees as it is an internal API explicitly documented as not
for driver usage that can change at any time.
next prev parent reply other threads:[~2019-10-30 22:38 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-30 21:12 ioc3_eth DMA API fixes Christoph Hellwig
2019-10-30 21:12 ` [PATCH 1/4] net: sgi: ioc3-eth: don't abuse dma_direct_* calls Christoph Hellwig
2019-10-30 22:05 ` Thomas Bogendoerfer
2019-10-30 22:38 ` Christoph Hellwig [this message]
2019-10-31 8:54 ` Thomas Bogendoerfer
2019-10-31 13:15 ` Christoph Hellwig
2019-10-31 15:18 ` Thomas Bogendoerfer
2019-10-31 17:01 ` Christoph Hellwig
2019-10-31 19:15 ` David Miller
2019-10-30 21:12 ` [PATCH 2/4] net: sgi: ioc3-eth: fix usage of GFP_* flags Christoph Hellwig
2019-10-30 21:12 ` [PATCH 3/4] net: sgi: ioc3-eth: simplify setting the DMA mask Christoph Hellwig
2019-10-30 21:12 ` [PATCH 4/4] net: sgi: ioc3-eth: fix setting NETIF_F_HIGHDMA Christoph Hellwig
2019-10-31 21:13 ` ioc3_eth DMA API fixes David Miller
2019-10-31 21:23 ` Christoph Hellwig
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