From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joerg Roedel Subject: Re: [PATCH v5 1/1] iommu-api: Add map_sg/unmap_sg functions Date: Mon, 18 Aug 2014 23:55:54 +0200 Message-ID: <20140818215553.GJ9809@8bytes.org> References: <1407797150-515-1-git-send-email-ohaugan@codeaurora.org> <1407797150-515-2-git-send-email-ohaugan@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <1407797150-515-2-git-send-email-ohaugan-sgV2jX0FEOL9JmXXK+q4OQ@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: Olav Haugan 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, kgene.kim-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org, dwmw2-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: linux-arm-msm@vger.kernel.org On Mon, Aug 11, 2014 at 03:45:50PM -0700, Olav Haugan wrote: > +int default_iommu_map_sg(struct iommu_domain *domain, unsigned long iova, > + struct scatterlist *sg, unsigned int nents, > + int prot, unsigned long flags) > +{ > + int ret = 0; > + unsigned long offset = 0; > + unsigned int i; > + struct scatterlist *s; > + > + for_each_sg(sg, s, nents, i) { > + phys_addr_t phys = page_to_phys(sg_page(s)); > + size_t page_len = s->offset + s->length; > + > + ret = iommu_map(domain, iova + offset, phys, page_len, > + prot); This isn't going to work, iova + offset, phys and page_len need to be aligned to the minimum page-size the given IOMMU implementation supports. See the iommu_map implementation for details. > +int default_iommu_unmap_sg(struct iommu_domain *domain, unsigned long iova, > + size_t size, unsigned long flags) Another asymmentry here, why don't you just pass a scatterlist and nents like in the map_sg function? if you implement it like this it is just a duplication of iommu_unmap(). > +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); > +} These function pointers need to be checked for != NULL before calling them. Joerg From mboxrd@z Thu Jan 1 00:00:00 1970 From: joro@8bytes.org (Joerg Roedel) Date: Mon, 18 Aug 2014 23:55:54 +0200 Subject: [PATCH v5 1/1] iommu-api: Add map_sg/unmap_sg functions In-Reply-To: <1407797150-515-2-git-send-email-ohaugan@codeaurora.org> References: <1407797150-515-1-git-send-email-ohaugan@codeaurora.org> <1407797150-515-2-git-send-email-ohaugan@codeaurora.org> Message-ID: <20140818215553.GJ9809@8bytes.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Mon, Aug 11, 2014 at 03:45:50PM -0700, Olav Haugan wrote: > +int default_iommu_map_sg(struct iommu_domain *domain, unsigned long iova, > + struct scatterlist *sg, unsigned int nents, > + int prot, unsigned long flags) > +{ > + int ret = 0; > + unsigned long offset = 0; > + unsigned int i; > + struct scatterlist *s; > + > + for_each_sg(sg, s, nents, i) { > + phys_addr_t phys = page_to_phys(sg_page(s)); > + size_t page_len = s->offset + s->length; > + > + ret = iommu_map(domain, iova + offset, phys, page_len, > + prot); This isn't going to work, iova + offset, phys and page_len need to be aligned to the minimum page-size the given IOMMU implementation supports. See the iommu_map implementation for details. > +int default_iommu_unmap_sg(struct iommu_domain *domain, unsigned long iova, > + size_t size, unsigned long flags) Another asymmentry here, why don't you just pass a scatterlist and nents like in the map_sg function? if you implement it like this it is just a duplication of iommu_unmap(). > +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); > +} These function pointers need to be checked for != NULL before calling them. Joerg