From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 17F09C282CE for ; Tue, 4 Jun 2019 18:11:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CFFCD20851 for ; Tue, 4 Jun 2019 18:11:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726312AbfFDSLR (ORCPT ); Tue, 4 Jun 2019 14:11:17 -0400 Received: from foss.arm.com ([217.140.101.70]:49124 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725933AbfFDSLR (ORCPT ); Tue, 4 Jun 2019 14:11:17 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id DA77D80D; Tue, 4 Jun 2019 11:11:15 -0700 (PDT) Received: from [10.1.196.75] (e110467-lin.cambridge.arm.com [10.1.196.75]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id AB4B13F690; Tue, 4 Jun 2019 11:11:10 -0700 (PDT) Subject: Re: [PATCH v3 1/4] iommu: Add gfp parameter to iommu_ops::map To: Tom Murphy , iommu@lists.linux-foundation.org Cc: murphyt7@tcd.ie, Joerg Roedel , Will Deacon , Marek Szyprowski , Kukjin Kim , Krzysztof Kozlowski , David Woodhouse , Andy Gross , David Brown , Matthias Brugger , Rob Clark , Heiko Stuebner , Gerald Schaefer , Thierry Reding , Jonathan Hunter , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-mediatek@lists.infradead.org, linux-rockchip@lists.infradead.org, linux-s390@vger.kernel.org, linux-tegra@vger.kernel.org References: <20190506185207.31069-1-tmurphy@arista.com> <20190506185207.31069-2-tmurphy@arista.com> From: Robin Murphy Message-ID: <33a1e3c1-1906-9e45-d060-e7998424973b@arm.com> Date: Tue, 4 Jun 2019 19:11:09 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <20190506185207.31069-2-tmurphy@arista.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 8bit Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On 06/05/2019 19:52, Tom Murphy wrote: > Add a gfp_t parameter to the iommu_ops::map function. > Remove the needless locking in the AMD iommu driver. > > The iommu_ops::map function (or the iommu_map function which calls it) > was always supposed to be sleepable (according to Joerg's comment in > this thread: https://lore.kernel.org/patchwork/patch/977520/ ) and so > should probably have had a "might_sleep()" since it was written. However > currently the dma-iommu api can call iommu_map in an atomic context, > which it shouldn't do. This doesn't cause any problems because any iommu > driver which uses the dma-iommu api uses gfp_atomic in it's > iommu_ops::map function. But doing this wastes the memory allocators > atomic pools. Hmm, in some cases iommu_ops::unmap may need to allocate as well, primarily if it needs to split a hugepage mapping. Should we pass flags through there as well, or are we prepared to assume that that case will happen rarely enough that it's fair to just assume GFP_ATOMIC? It won't happen for DMA ops, but it's conceivable that other users such as GPU drivers might make partial unmaps, and I doubt we could totally rule out the wackiest ones doing so from non-sleeping contexts. Robin. > We can remove the mutex lock from amd_iommu_map and amd_iommu_unmap. > iommu_map doesn’t lock while mapping and so no two calls should touch > the same iova range. The AMD driver already handles the page table page > allocations without locks so we can safely remove the locks. > > Signed-off-by: Tom Murphy > --- > drivers/iommu/amd_iommu.c | 14 ++++------- > drivers/iommu/arm-smmu-v3.c | 2 +- > drivers/iommu/arm-smmu.c | 2 +- > drivers/iommu/dma-iommu.c | 6 ++--- > drivers/iommu/exynos-iommu.c | 2 +- > drivers/iommu/intel-iommu.c | 2 +- > drivers/iommu/iommu.c | 43 +++++++++++++++++++++++++++++----- > drivers/iommu/ipmmu-vmsa.c | 2 +- > drivers/iommu/msm_iommu.c | 2 +- > drivers/iommu/mtk_iommu.c | 2 +- > drivers/iommu/mtk_iommu_v1.c | 2 +- > drivers/iommu/omap-iommu.c | 2 +- > drivers/iommu/qcom_iommu.c | 2 +- > drivers/iommu/rockchip-iommu.c | 2 +- > drivers/iommu/s390-iommu.c | 2 +- > drivers/iommu/tegra-gart.c | 2 +- > drivers/iommu/tegra-smmu.c | 2 +- > include/linux/iommu.h | 21 ++++++++++++++++- > 18 files changed, 78 insertions(+), 34 deletions(-) > > diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c > index ebd062522cf5..ea3a5dc61bb0 100644 > --- a/drivers/iommu/amd_iommu.c > +++ b/drivers/iommu/amd_iommu.c > @@ -3092,7 +3092,8 @@ static int amd_iommu_attach_device(struct iommu_domain *dom, > } > > static int amd_iommu_map(struct iommu_domain *dom, unsigned long iova, > - phys_addr_t paddr, size_t page_size, int iommu_prot) > + phys_addr_t paddr, size_t page_size, int iommu_prot, > + gfp_t gfp) > { > struct protection_domain *domain = to_pdomain(dom); > int prot = 0; > @@ -3106,9 +3107,7 @@ static int amd_iommu_map(struct iommu_domain *dom, unsigned long iova, > if (iommu_prot & IOMMU_WRITE) > prot |= IOMMU_PROT_IW; > > - mutex_lock(&domain->api_lock); > - ret = iommu_map_page(domain, iova, paddr, page_size, prot, GFP_KERNEL); > - mutex_unlock(&domain->api_lock); > + ret = iommu_map_page(domain, iova, paddr, page_size, prot, gfp); > > domain_flush_np_cache(domain, iova, page_size); > > @@ -3119,16 +3118,11 @@ static size_t amd_iommu_unmap(struct iommu_domain *dom, unsigned long iova, > size_t page_size) > { > struct protection_domain *domain = to_pdomain(dom); > - size_t unmap_size; > > if (domain->mode == PAGE_MODE_NONE) > return 0; > > - mutex_lock(&domain->api_lock); > - unmap_size = iommu_unmap_page(domain, iova, page_size); > - mutex_unlock(&domain->api_lock); > - > - return unmap_size; > + return iommu_unmap_page(domain, iova, page_size); > } > > static phys_addr_t amd_iommu_iova_to_phys(struct iommu_domain *dom, > diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c > index d3880010c6cf..e5c48089b49f 100644 > --- a/drivers/iommu/arm-smmu-v3.c > +++ b/drivers/iommu/arm-smmu-v3.c > @@ -1777,7 +1777,7 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) > } > > static int arm_smmu_map(struct iommu_domain *domain, unsigned long iova, > - phys_addr_t paddr, size_t size, int prot) > + phys_addr_t paddr, size_t size, int prot, gfp_t gfp) > { > struct io_pgtable_ops *ops = to_smmu_domain(domain)->pgtbl_ops; > > diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c > index 045d93884164..2d50db55b788 100644 > --- a/drivers/iommu/arm-smmu.c > +++ b/drivers/iommu/arm-smmu.c > @@ -1286,7 +1286,7 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) > } > > static int arm_smmu_map(struct iommu_domain *domain, unsigned long iova, > - phys_addr_t paddr, size_t size, int prot) > + phys_addr_t paddr, size_t size, int prot, gfp_t gfp) > { > struct io_pgtable_ops *ops = to_smmu_domain(domain)->pgtbl_ops; > struct arm_smmu_device *smmu = to_smmu_domain(domain)->smmu; > diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c > index fa5713a4f6f8..7a96c2c8f56b 100644 > --- a/drivers/iommu/dma-iommu.c > +++ b/drivers/iommu/dma-iommu.c > @@ -440,7 +440,7 @@ static dma_addr_t __iommu_dma_map(struct device *dev, phys_addr_t phys, > if (!iova) > return DMA_MAPPING_ERROR; > > - if (iommu_map(domain, iova, phys - iova_off, size, prot)) { > + if (iommu_map_atomic(domain, iova, phys - iova_off, size, prot)) { > iommu_dma_free_iova(cookie, iova, size); > return DMA_MAPPING_ERROR; > } > @@ -641,7 +641,7 @@ static void *iommu_dma_alloc_remap(struct device *dev, size_t size, > arch_dma_prep_coherent(sg_page(sg), sg->length); > } > > - if (iommu_map_sg(domain, iova, sgt.sgl, sgt.orig_nents, ioprot) > + if (iommu_map_sg_atomic(domain, iova, sgt.sgl, sgt.orig_nents, ioprot) > < size) > goto out_free_sg; > > @@ -1003,7 +1003,7 @@ static int iommu_dma_map_sg(struct device *dev, struct scatterlist *sg, > * We'll leave any physical concatenation to the IOMMU driver's > * implementation - it knows better than we do. > */ > - if (iommu_map_sg(domain, iova, sg, nents, prot) < iova_len) > + if (iommu_map_sg_atomic(domain, iova, sg, nents, prot) < iova_len) > goto out_free_iova; > > return __finalise_sg(dev, sg, nents, iova); > diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c > index 05c6bc099d62..46414234c179 100644 > --- a/drivers/iommu/exynos-iommu.c > +++ b/drivers/iommu/exynos-iommu.c > @@ -1078,7 +1078,7 @@ static int lv2set_page(sysmmu_pte_t *pent, phys_addr_t paddr, size_t size, > */ > static int exynos_iommu_map(struct iommu_domain *iommu_domain, > unsigned long l_iova, phys_addr_t paddr, size_t size, > - int prot) > + int prot, gfp_t gfp) > { > struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain); > sysmmu_pte_t *entry; > diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c > index 28cb713d728c..4f0ff28f7cb9 100644 > --- a/drivers/iommu/intel-iommu.c > +++ b/drivers/iommu/intel-iommu.c > @@ -5137,7 +5137,7 @@ static void intel_iommu_detach_device(struct iommu_domain *domain, > > static int intel_iommu_map(struct iommu_domain *domain, > unsigned long iova, phys_addr_t hpa, > - size_t size, int iommu_prot) > + size_t size, int iommu_prot, gfp_t gfp) > { > struct dmar_domain *dmar_domain = to_dmar_domain(domain); > u64 max_addr; > diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c > index 109de67d5d72..1b49841c177e 100644 > --- a/drivers/iommu/iommu.c > +++ b/drivers/iommu/iommu.c > @@ -1584,8 +1584,8 @@ static size_t iommu_pgsize(struct iommu_domain *domain, > return pgsize; > } > > -int iommu_map(struct iommu_domain *domain, unsigned long iova, > - phys_addr_t paddr, size_t size, int prot) > +int __iommu_map(struct iommu_domain *domain, unsigned long iova, > + phys_addr_t paddr, size_t size, int prot, gfp_t gfp) > { > const struct iommu_ops *ops = domain->ops; > unsigned long orig_iova = iova; > @@ -1622,8 +1622,8 @@ int iommu_map(struct iommu_domain *domain, unsigned long iova, > > pr_debug("mapping: iova 0x%lx pa %pa pgsize 0x%zx\n", > iova, &paddr, pgsize); > + ret = ops->map(domain, iova, paddr, pgsize, prot, gfp); > > - ret = ops->map(domain, iova, paddr, pgsize, prot); > if (ret) > break; > > @@ -1643,8 +1643,22 @@ int iommu_map(struct iommu_domain *domain, unsigned long iova, > > return ret; > } > + > +int iommu_map(struct iommu_domain *domain, unsigned long iova, > + phys_addr_t paddr, size_t size, int prot) > +{ > + might_sleep(); > + return __iommu_map(domain, iova, paddr, size, prot, GFP_KERNEL); > +} > EXPORT_SYMBOL_GPL(iommu_map); > > +int iommu_map_atomic(struct iommu_domain *domain, unsigned long iova, > + phys_addr_t paddr, size_t size, int prot) > +{ > + return __iommu_map(domain, iova, paddr, size, prot, GFP_ATOMIC); > +} > +EXPORT_SYMBOL_GPL(iommu_map_atomic); > + > static size_t __iommu_unmap(struct iommu_domain *domain, > unsigned long iova, size_t size, > bool sync) > @@ -1719,8 +1733,9 @@ size_t iommu_unmap_fast(struct iommu_domain *domain, > } > EXPORT_SYMBOL_GPL(iommu_unmap_fast); > > -size_t iommu_map_sg(struct iommu_domain *domain, unsigned long iova, > - struct scatterlist *sg, unsigned int nents, int prot) > +size_t __iommu_map_sg(struct iommu_domain *domain, unsigned long iova, > + struct scatterlist *sg, unsigned int nents, int prot, > + gfp_t gfp) > { > size_t len = 0, mapped = 0; > phys_addr_t start; > @@ -1731,7 +1746,9 @@ size_t iommu_map_sg(struct iommu_domain *domain, unsigned long iova, > phys_addr_t s_phys = sg_phys(sg); > > if (len && s_phys != start + len) { > - ret = iommu_map(domain, iova + mapped, start, len, prot); > + ret = __iommu_map(domain, iova + mapped, start, > + len, prot, gfp); > + > if (ret) > goto out_err; > > @@ -1759,8 +1776,22 @@ size_t iommu_map_sg(struct iommu_domain *domain, unsigned long iova, > return 0; > > } > + > +size_t iommu_map_sg(struct iommu_domain *domain, unsigned long iova, > + struct scatterlist *sg, unsigned int nents, int prot) > +{ > + might_sleep(); > + return __iommu_map_sg(domain, iova, sg, nents, prot, GFP_KERNEL); > +} > EXPORT_SYMBOL_GPL(iommu_map_sg); > > +size_t iommu_map_sg_atomic(struct iommu_domain *domain, unsigned long iova, > + struct scatterlist *sg, unsigned int nents, int prot) > +{ > + return __iommu_map_sg(domain, iova, sg, nents, prot, GFP_ATOMIC); > +} > +EXPORT_SYMBOL_GPL(iommu_map_sg_atomic); > + > int iommu_domain_window_enable(struct iommu_domain *domain, u32 wnd_nr, > phys_addr_t paddr, u64 size, int prot) > { > diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c > index 9a380c10655e..e005c83d49d8 100644 > --- a/drivers/iommu/ipmmu-vmsa.c > +++ b/drivers/iommu/ipmmu-vmsa.c > @@ -707,7 +707,7 @@ static void ipmmu_detach_device(struct iommu_domain *io_domain, > } > > static int ipmmu_map(struct iommu_domain *io_domain, unsigned long iova, > - phys_addr_t paddr, size_t size, int prot) > + phys_addr_t paddr, size_t size, int prot, gfp_t gfp) > { > struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain); > > diff --git a/drivers/iommu/msm_iommu.c b/drivers/iommu/msm_iommu.c > index 9fb0eb7a4d02..3f6bf3653aa2 100644 > --- a/drivers/iommu/msm_iommu.c > +++ b/drivers/iommu/msm_iommu.c > @@ -508,7 +508,7 @@ static void msm_iommu_detach_dev(struct iommu_domain *domain, > } > > static int msm_iommu_map(struct iommu_domain *domain, unsigned long iova, > - phys_addr_t pa, size_t len, int prot) > + phys_addr_t pa, size_t len, int prot, gfp_t gfp) > { > struct msm_priv *priv = to_msm_priv(domain); > unsigned long flags; > diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c > index de3e02277b70..3176b9b54d4d 100644 > --- a/drivers/iommu/mtk_iommu.c > +++ b/drivers/iommu/mtk_iommu.c > @@ -364,7 +364,7 @@ static void mtk_iommu_detach_device(struct iommu_domain *domain, > } > > static int mtk_iommu_map(struct iommu_domain *domain, unsigned long iova, > - phys_addr_t paddr, size_t size, int prot) > + phys_addr_t paddr, size_t size, int prot, gfp_t gfp) > { > struct mtk_iommu_domain *dom = to_mtk_domain(domain); > unsigned long flags; > diff --git a/drivers/iommu/mtk_iommu_v1.c b/drivers/iommu/mtk_iommu_v1.c > index 52b01e3a49df..e7b1907faec1 100644 > --- a/drivers/iommu/mtk_iommu_v1.c > +++ b/drivers/iommu/mtk_iommu_v1.c > @@ -303,7 +303,7 @@ static void mtk_iommu_detach_device(struct iommu_domain *domain, > } > > static int mtk_iommu_map(struct iommu_domain *domain, unsigned long iova, > - phys_addr_t paddr, size_t size, int prot) > + phys_addr_t paddr, size_t size, int prot, gfp_t gfp) > { > struct mtk_iommu_domain *dom = to_mtk_domain(domain); > unsigned int page_num = size >> MT2701_IOMMU_PAGE_SHIFT; > diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c > index d2fb347aa4ff..c1d5a71285dc 100644 > --- a/drivers/iommu/omap-iommu.c > +++ b/drivers/iommu/omap-iommu.c > @@ -1109,7 +1109,7 @@ static u32 iotlb_init_entry(struct iotlb_entry *e, u32 da, u32 pa, int pgsz) > } > > static int omap_iommu_map(struct iommu_domain *domain, unsigned long da, > - phys_addr_t pa, size_t bytes, int prot) > + phys_addr_t pa, size_t bytes, int prot, gfp_t gfp) > { > struct omap_iommu_domain *omap_domain = to_omap_domain(domain); > struct device *dev = omap_domain->dev; > diff --git a/drivers/iommu/qcom_iommu.c b/drivers/iommu/qcom_iommu.c > index 8cdd3f059513..a01e07a4e76f 100644 > --- a/drivers/iommu/qcom_iommu.c > +++ b/drivers/iommu/qcom_iommu.c > @@ -411,7 +411,7 @@ static void qcom_iommu_detach_dev(struct iommu_domain *domain, struct device *de > } > > static int qcom_iommu_map(struct iommu_domain *domain, unsigned long iova, > - phys_addr_t paddr, size_t size, int prot) > + phys_addr_t paddr, size_t size, int prot, gfp_t gfp) > { > int ret; > unsigned long flags; > diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c > index 77d4bd93fe4b..aa3507f35107 100644 > --- a/drivers/iommu/rockchip-iommu.c > +++ b/drivers/iommu/rockchip-iommu.c > @@ -760,7 +760,7 @@ static int rk_iommu_map_iova(struct rk_iommu_domain *rk_domain, u32 *pte_addr, > } > > static int rk_iommu_map(struct iommu_domain *domain, unsigned long _iova, > - phys_addr_t paddr, size_t size, int prot) > + phys_addr_t paddr, size_t size, int prot, gfp_t gfp) > { > struct rk_iommu_domain *rk_domain = to_rk_domain(domain); > unsigned long flags; > diff --git a/drivers/iommu/s390-iommu.c b/drivers/iommu/s390-iommu.c > index 22d4db302c1c..efa6aa68521d 100644 > --- a/drivers/iommu/s390-iommu.c > +++ b/drivers/iommu/s390-iommu.c > @@ -265,7 +265,7 @@ static int s390_iommu_update_trans(struct s390_domain *s390_domain, > } > > static int s390_iommu_map(struct iommu_domain *domain, unsigned long iova, > - phys_addr_t paddr, size_t size, int prot) > + phys_addr_t paddr, size_t size, int prot, gfp_t gfp) > { > struct s390_domain *s390_domain = to_s390_domain(domain); > int flags = ZPCI_PTE_VALID, rc = 0; > diff --git a/drivers/iommu/tegra-gart.c b/drivers/iommu/tegra-gart.c > index 4d8057916552..f300099852b1 100644 > --- a/drivers/iommu/tegra-gart.c > +++ b/drivers/iommu/tegra-gart.c > @@ -190,7 +190,7 @@ static inline int __gart_iommu_map(struct gart_device *gart, unsigned long iova, > } > > static int gart_iommu_map(struct iommu_domain *domain, unsigned long iova, > - phys_addr_t pa, size_t bytes, int prot) > + phys_addr_t pa, size_t bytes, int prot, gfp_t gfp) > { > struct gart_device *gart = gart_handle; > int ret; > diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c > index 5182c7d6171e..e1bf867e0607 100644 > --- a/drivers/iommu/tegra-smmu.c > +++ b/drivers/iommu/tegra-smmu.c > @@ -641,7 +641,7 @@ static void tegra_smmu_set_pte(struct tegra_smmu_as *as, unsigned long iova, > } > > static int tegra_smmu_map(struct iommu_domain *domain, unsigned long iova, > - phys_addr_t paddr, size_t size, int prot) > + phys_addr_t paddr, size_t size, int prot, gfp_t gfp) > { > struct tegra_smmu_as *as = to_smmu_as(domain); > dma_addr_t pte_dma; > diff --git a/include/linux/iommu.h b/include/linux/iommu.h > index ffbbc7e39cee..76b8e7fe3ed0 100644 > --- a/include/linux/iommu.h > +++ b/include/linux/iommu.h > @@ -198,7 +198,7 @@ struct iommu_ops { > int (*attach_dev)(struct iommu_domain *domain, struct device *dev); > void (*detach_dev)(struct iommu_domain *domain, struct device *dev); > int (*map)(struct iommu_domain *domain, unsigned long iova, > - phys_addr_t paddr, size_t size, int prot); > + phys_addr_t paddr, size_t size, int prot, gfp_t gfp); > size_t (*unmap)(struct iommu_domain *domain, unsigned long iova, > size_t size); > void (*flush_iotlb_all)(struct iommu_domain *domain); > @@ -295,12 +295,17 @@ extern struct iommu_domain *iommu_get_domain_for_dev(struct device *dev); > extern struct iommu_domain *iommu_get_dma_domain(struct device *dev); > extern int iommu_map(struct iommu_domain *domain, unsigned long iova, > phys_addr_t paddr, size_t size, int prot); > +extern int iommu_map_atomic(struct iommu_domain *domain, unsigned long iova, > + phys_addr_t paddr, size_t size, int prot); > extern size_t iommu_unmap(struct iommu_domain *domain, unsigned long iova, > size_t size); > extern size_t iommu_unmap_fast(struct iommu_domain *domain, > unsigned long iova, size_t size); > extern size_t iommu_map_sg(struct iommu_domain *domain, unsigned long iova, > struct scatterlist *sg,unsigned int nents, int prot); > +extern size_t iommu_map_sg_atomic(struct iommu_domain *domain, > + unsigned long iova, struct scatterlist *sg, > + unsigned int nents, int prot); > extern phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova); > extern void iommu_set_fault_handler(struct iommu_domain *domain, > iommu_fault_handler_t handler, void *token); > @@ -469,6 +474,13 @@ static inline int iommu_map(struct iommu_domain *domain, unsigned long iova, > return -ENODEV; > } > > +static inline int iommu_map_atomic(struct iommu_domain *domain, > + unsigned long iova, phys_addr_t paddr, > + size_t size, int prot) > +{ > + return -ENODEV; > +} > + > static inline size_t iommu_unmap(struct iommu_domain *domain, > unsigned long iova, size_t size) > { > @@ -488,6 +500,13 @@ static inline size_t iommu_map_sg(struct iommu_domain *domain, > return 0; > } > > +static inline size_t iommu_map_sg_atomic(struct iommu_domain *domain, > + unsigned long iova, struct scatterlist *sg, > + unsigned int nents, int prot) > +{ > + return 0; > +} > + > static inline void iommu_flush_tlb_all(struct iommu_domain *domain) > { > } >