From mboxrd@z Thu Jan 1 00:00:00 1970 From: konrad.wilk@oracle.com (Konrad Rzeszutek Wilk) Date: Thu, 19 May 2016 10:22:48 -0400 Subject: [PATCHv6 3/8] dma-mapping: add dma_{map,unmap}_resource In-Reply-To: <20160519112926.GO29375@bigcity.dyn.berto.se> References: <1462812247-3414-1-git-send-email-niklas.soderlund+renesas@ragnatech.se> <1462812247-3414-4-git-send-email-niklas.soderlund+renesas@ragnatech.se> <20160517145445.GE4074@char.us.oracle.com> <20160519112926.GO29375@bigcity.dyn.berto.se> Message-ID: <20160519142248.GB21691@localhost.localdomain> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, May 19, 2016 at 01:29:26PM +0200, Niklas S?derlund wrote: > Hi Konrad, > > Thanks for your feedback. > > On 2016-05-17 10:54:45 -0400, Konrad Rzeszutek Wilk wrote: > > > > > > -In some circumstances dma_map_single() and dma_map_page() will fail to create > > > -a mapping. A driver can check for these errors by testing the returned > > > -DMA address with dma_mapping_error(). A non-zero return value means the mapping > > > -could not be created and the driver should take appropriate action (e.g. > > > -reduce current DMA mapping usage or delay and try again later). > > > +In some circumstances dma_map_single(), dma_map_page() and dma_map_resource() > > > +will fail to create a mapping. A driver can check for these errors by testing > > > +the returned DMA address with dma_mapping_error(). A non-zero return value > > > +means the mapping could not be created and the driver should take appropriate > > > +action (e.g. reduce current DMA mapping usage or delay and try again later). > > > > This looks like it belongs to another patch? > > No it is correct (at least intended to be in this patch). All it really > do is inject dma_map_resource() (which is added in this patch) as one of > the calls which return dma_addr_t should be checked for error using > dma_mapping_error(). But yes the change effect all lines in the > paragraph due to line wrapping. > > Hum or maybe I'm misunderstanding your question. I totally missed the 'dma_map_resource' in there and just read 'dma_mapping_error'! Thanks. > > -- > Regards, > Niklas S?derlund