From mboxrd@z Thu Jan 1 00:00:00 1970 From: Olav Haugan Subject: Re: [PATCH v5 1/1] iommu-api: Add map_sg/unmap_sg functions Date: Mon, 06 Oct 2014 12:02:47 -0700 Message-ID: <5432E757.10201@codeaurora.org> References: <1407797150-515-1-git-send-email-ohaugan@codeaurora.org> <1407797150-515-2-git-send-email-ohaugan@codeaurora.org> <20140925170108.GE8306@8bytes.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20140925170108.GE8306-zLv9SwRftAIdnm+yROfE0A@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Joerg Roedel Cc: laurent.pinchart+renesas-ryLnwIuWjnjg/C1BVhZhaw@public.gmane.org, linux-arm-msm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, will.deacon-5wv7dgnIgG8@public.gmane.org, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, thierry.reding-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, Varun.Sethi-KZfg59tc24xl57MIdRCFDg@public.gmane.org, dwmw2-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org, kgene.kim-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: linux-arm-msm@vger.kernel.org On 9/25/2014 10:01 AM, Joerg Roedel wrote: > On Mon, Aug 11, 2014 at 03:45:50PM -0700, Olav Haugan wrote: >> +static inline int iommu_map_sg(struct iommu_domain *domain, unsigned long iova, >> + struct scatterlist *sg, unsigned int nents, >> + int prot, unsigned long flags) >> +{ >> + return domain->ops->map_sg(domain, iova, sg, nents, prot, flags); >> +} >> + >> +static inline int iommu_unmap_sg(struct iommu_domain *domain, >> + unsigned long iova, size_t size, >> + unsigned long flags) >> +{ >> + return domain->ops->unmap_sg(domain, iova, size, flags); >> +} > > I have thought a little bit more about this interface and think that it > would be better to just return a size_t from iommu_map_sg(). The > function returns the amount of address space mapped by it, 0 in the > worst case. > > This makes it easy to unmap the region just with > iommu_unmap(domain, iova, size) in the end and removing the need for a > new iommu_unmap_sg() function. Also the error-path of the map_sg > call-backs becomes easier as the function then just returns the amount > of address-space already mapped before the error happened. > > So the prototype would be: > > size_t iommu_map_sg(struct iommu_domain *domain, > unsigned long iova, > struct scatterlist *sg, > unsigned int nents, > int prot); > > (as I said before, the flags parameter should not be added by this > patch-set). > Ok, sounds good. I'll post v6 soon. .Olav -- The Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation From mboxrd@z Thu Jan 1 00:00:00 1970 From: ohaugan@codeaurora.org (Olav Haugan) Date: Mon, 06 Oct 2014 12:02:47 -0700 Subject: [PATCH v5 1/1] iommu-api: Add map_sg/unmap_sg functions In-Reply-To: <20140925170108.GE8306@8bytes.org> References: <1407797150-515-1-git-send-email-ohaugan@codeaurora.org> <1407797150-515-2-git-send-email-ohaugan@codeaurora.org> <20140925170108.GE8306@8bytes.org> Message-ID: <5432E757.10201@codeaurora.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 9/25/2014 10:01 AM, Joerg Roedel wrote: > On Mon, Aug 11, 2014 at 03:45:50PM -0700, Olav Haugan wrote: >> +static inline int iommu_map_sg(struct iommu_domain *domain, unsigned long iova, >> + struct scatterlist *sg, unsigned int nents, >> + int prot, unsigned long flags) >> +{ >> + return domain->ops->map_sg(domain, iova, sg, nents, prot, flags); >> +} >> + >> +static inline int iommu_unmap_sg(struct iommu_domain *domain, >> + unsigned long iova, size_t size, >> + unsigned long flags) >> +{ >> + return domain->ops->unmap_sg(domain, iova, size, flags); >> +} > > I have thought a little bit more about this interface and think that it > would be better to just return a size_t from iommu_map_sg(). The > function returns the amount of address space mapped by it, 0 in the > worst case. > > This makes it easy to unmap the region just with > iommu_unmap(domain, iova, size) in the end and removing the need for a > new iommu_unmap_sg() function. Also the error-path of the map_sg > call-backs becomes easier as the function then just returns the amount > of address-space already mapped before the error happened. > > So the prototype would be: > > size_t iommu_map_sg(struct iommu_domain *domain, > unsigned long iova, > struct scatterlist *sg, > unsigned int nents, > int prot); > > (as I said before, the flags parameter should not be added by this > patch-set). > Ok, sounds good. I'll post v6 soon. .Olav -- The Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation