From patchwork Wed Nov 6 13:49:35 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Leon Romanovsky X-Patchwork-Id: 13864532 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D96C51E1A28; Wed, 6 Nov 2024 11:50:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730893819; cv=none; b=ZHrIiBSWIJ68XWMAydHoh8d9p8sDpCNu+DxhpIcJduFOm7wNwsHx2KzILyX3JsrRVoxTT4NXPvk58DPPybyQD79f1DsbNAPV96c7i7JtwTZeuA1SVj7hukQ2UbYTv7ajSacNb/wrF3/9M1UyW/VFjc6v0gZ1jLg63xRlYQG/6Uo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730893819; c=relaxed/simple; bh=6bk4WY4n6+Z+yYl3isWCsOJQFnSfMGq0h01rMvpfa/0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=eSFVgxgpf8kVKPmsoNB4BiKiRMalyputaYKz/Q+3oh05gGhCefNIFrWF8EfEwYbWhQXPlNcRVLhehevOKeWbvzG95fh+UR4eikOE9n1Ef603iCGmg8zM5TNPdEOEuYLNF01LNijQbFvXHgLgJ3+cX3NbL/RKyS18jLxLWJsVGmA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=N9ZyBRYG; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="N9ZyBRYG" Received: by smtp.kernel.org (Postfix) with ESMTPSA id F2D70C4CECD; Wed, 6 Nov 2024 11:50:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1730893818; bh=6bk4WY4n6+Z+yYl3isWCsOJQFnSfMGq0h01rMvpfa/0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=N9ZyBRYGBKRQCx48wgDGRq+lXDQbrdZs1zQzADKYBz7tU6caFEMRX5DkgQjZce5k1 WH5HeYXTswRnISibi5HFBoiyEfB0jy4uy+ZleZ5Z38T0RtSxF80WF9xXonRyCmBMal vJ6SMXE2uA1hFa85fXuNJX7zuZ4EFv5wuaCbEsVW+YJPUSTzoKrwrT89tmTqgzc+Zk 64Fhyi52hiIEv3cJ2FdfRJEyHTDgfOvseiTAMGYAq2OTLWLCUSjOR1uJWwp+oSlKWR l/hTIY4mS/bxpi+LMmDDMPxzzITxQEZElzZ0GXaIutByQMf6p8YnaZS6ouAbvc+125 0RjzE1qk9ENOw== From: Leon Romanovsky To: Jens Axboe , Jason Gunthorpe , Robin Murphy , Joerg Roedel , Will Deacon , Christoph Hellwig , Sagi Grimberg Cc: Leon Romanovsky , Keith Busch , Bjorn Helgaas , Logan Gunthorpe , Yishai Hadas , Shameer Kolothum , Kevin Tian , Alex Williamson , Marek Szyprowski , =?utf-8?b?SsOpcsO0bWUgR2xpc3Nl?= , Andrew Morton , Jonathan Corbet , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, linux-rdma@vger.kernel.org, iommu@lists.linux.dev, linux-nvme@lists.infradead.org, linux-pci@vger.kernel.org, kvm@vger.kernel.org, linux-mm@kvack.org, Randy Dunlap Subject: [PATCH v2 07/17] dma-mapping: Implement link/unlink ranges API Date: Wed, 6 Nov 2024 15:49:35 +0200 Message-ID: X-Mailer: git-send-email 2.47.0 In-Reply-To: References: Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Leon Romanovsky Introduce new DMA APIs to perform DMA linkage of buffers in layers higher than DMA. In proposed API, the callers will perform the following steps. In map path: if (dma_can_use_iova(...)) dma_iova_alloc() for (page in range) dma_iova_link_next(...) dma_iova_sync(...) else /* Fallback to legacy map pages */ for (all pages) dma_map_page(...) In unmap path: if (dma_can_use_iova(...)) dma_iova_destroy() else for (all pages) dma_unmap_page(...) Signed-off-by: Leon Romanovsky --- drivers/iommu/dma-iommu.c | 259 ++++++++++++++++++++++++++++++++++++ include/linux/dma-mapping.h | 32 +++++ 2 files changed, 291 insertions(+) diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index e1eaad500d27..4a504a879cc0 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -1834,6 +1834,265 @@ void dma_iova_free(struct device *dev, struct dma_iova_state *state) } EXPORT_SYMBOL_GPL(dma_iova_free); +static int __dma_iova_link(struct device *dev, dma_addr_t addr, + phys_addr_t phys, size_t size, enum dma_data_direction dir, + unsigned long attrs) +{ + bool coherent = dev_is_dma_coherent(dev); + + if (!coherent && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) + arch_sync_dma_for_device(phys, size, dir); + + return iommu_map_nosync(iommu_get_dma_domain(dev), addr, phys, size, + dma_info_to_prot(dir, coherent, attrs), GFP_ATOMIC); +} + +static int iommu_dma_iova_bounce_and_link(struct device *dev, dma_addr_t addr, + phys_addr_t phys, size_t bounce_len, + enum dma_data_direction dir, unsigned long attrs, + size_t iova_start_pad) +{ + struct iommu_domain *domain = iommu_get_dma_domain(dev); + struct iova_domain *iovad = &domain->iova_cookie->iovad; + phys_addr_t bounce_phys; + int error; + + bounce_phys = iommu_dma_map_swiotlb(dev, phys, bounce_len, dir, attrs); + if (bounce_phys == DMA_MAPPING_ERROR) + return -ENOMEM; + + error = __dma_iova_link(dev, addr - iova_start_pad, + bounce_phys - iova_start_pad, + iova_align(iovad, bounce_len), dir, attrs); + if (error) + swiotlb_tbl_unmap_single(dev, bounce_phys, bounce_len, dir, + attrs); + return error; +} + +static int iommu_dma_iova_link_swiotlb(struct device *dev, + struct dma_iova_state *state, phys_addr_t phys, size_t offset, + size_t size, enum dma_data_direction dir, unsigned long attrs) +{ + struct iommu_domain *domain = iommu_get_dma_domain(dev); + struct iommu_dma_cookie *cookie = domain->iova_cookie; + struct iova_domain *iovad = &cookie->iovad; + size_t iova_start_pad = iova_offset(iovad, phys); + size_t iova_end_pad = iova_offset(iovad, phys + size); + dma_addr_t addr = state->addr + offset; + size_t mapped = 0; + int error; + + if (iova_start_pad) { + size_t bounce_len = min(size, iovad->granule - iova_start_pad); + + error = iommu_dma_iova_bounce_and_link(dev, addr, phys, + bounce_len, dir, attrs, iova_start_pad); + if (error) + return error; + state->__size |= DMA_IOVA_USE_SWIOTLB; + + mapped += bounce_len; + size -= bounce_len; + if (!size) + return 0; + } + + size -= iova_end_pad; + error = __dma_iova_link(dev, addr + mapped, phys + mapped, size, dir, + attrs); + if (error) + goto out_unmap; + mapped += size; + + if (iova_end_pad) { + error = iommu_dma_iova_bounce_and_link(dev, addr + mapped, + phys + mapped, iova_end_pad, dir, attrs, 0); + if (error) + goto out_unmap; + state->__size |= DMA_IOVA_USE_SWIOTLB; + } + + return 0; + +out_unmap: + dma_iova_unlink(dev, state, 0, mapped, dir, attrs); + return error; +} + +/** + * dma_iova_link - Link a range of IOVA space + * @dev: DMA device + * @state: IOVA state + * @phys: physical address to link + * @offset: offset into the IOVA state to map into + * @size: size of the buffer + * @dir: DMA direction + * @attrs: attributes of mapping properties + * + * Link a range of IOVA space for the given IOVA state without IOTLB sync. + * This function is used to link multiple physical addresses in contigueous + * IOVA space without performing costly IOTLB sync. + * + * The caller is responsible to call to dma_iova_sync() to sync IOTLB at + * the end of linkage. + */ +int dma_iova_link(struct device *dev, struct dma_iova_state *state, + phys_addr_t phys, size_t offset, size_t size, + enum dma_data_direction dir, unsigned long attrs) +{ + struct iommu_domain *domain = iommu_get_dma_domain(dev); + struct iommu_dma_cookie *cookie = domain->iova_cookie; + struct iova_domain *iovad = &cookie->iovad; + size_t iova_start_pad = iova_offset(iovad, phys); + + if (WARN_ON_ONCE(iova_start_pad && offset > 0)) + return -EIO; + + if (dev_use_swiotlb(dev, size, dir) && iova_offset(iovad, phys | size)) + return iommu_dma_iova_link_swiotlb(dev, state, phys, offset, + size, dir, attrs); + + return __dma_iova_link(dev, state->addr + offset - iova_start_pad, + phys - iova_start_pad, + iova_align(iovad, size + iova_start_pad), dir, attrs); +} +EXPORT_SYMBOL_GPL(dma_iova_link); + +/** + * dma_iova_sync - Sync IOTLB + * @dev: DMA device + * @state: IOVA state + * @offset: offset into the IOVA state to sync + * @size: size of the buffer + * + * Sync IOTLB for the given IOVA state. This function should be called on + * the IOVA-contigous range created by one ore more dma_iova_link() calls + * to sync the IOTLB. + */ +int dma_iova_sync(struct device *dev, struct dma_iova_state *state, + size_t offset, size_t size) +{ + struct iommu_domain *domain = iommu_get_dma_domain(dev); + struct iommu_dma_cookie *cookie = domain->iova_cookie; + struct iova_domain *iovad = &cookie->iovad; + dma_addr_t addr = state->addr + offset; + size_t iova_start_pad = iova_offset(iovad, addr); + + return iommu_sync_map(domain, addr - iova_start_pad, + iova_align(iovad, size + iova_start_pad)); +} +EXPORT_SYMBOL_GPL(dma_iova_sync); + +static void iommu_dma_iova_unlink_range_slow(struct device *dev, + dma_addr_t addr, size_t size, enum dma_data_direction dir, + unsigned long attrs) +{ + struct iommu_domain *domain = iommu_get_dma_domain(dev); + struct iommu_dma_cookie *cookie = domain->iova_cookie; + struct iova_domain *iovad = &cookie->iovad; + size_t iova_start_pad = iova_offset(iovad, addr); + dma_addr_t end = addr + size; + + do { + phys_addr_t phys; + size_t len; + + phys = iommu_iova_to_phys(domain, addr); + if (WARN_ON(!phys)) + continue; + len = min_t(size_t, + end - addr, iovad->granule - iova_start_pad); + + if (!dev_is_dma_coherent(dev) && + !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) + arch_sync_dma_for_cpu(phys, len, dir); + + swiotlb_tbl_unmap_single(dev, phys, len, dir, attrs); + + addr += len; + iova_start_pad = 0; + } while (addr < end); +} + +static void __iommu_dma_iova_unlink(struct device *dev, + struct dma_iova_state *state, size_t offset, size_t size, + enum dma_data_direction dir, unsigned long attrs, + bool free_iova) +{ + struct iommu_domain *domain = iommu_get_dma_domain(dev); + struct iommu_dma_cookie *cookie = domain->iova_cookie; + struct iova_domain *iovad = &cookie->iovad; + dma_addr_t addr = state->addr + offset; + size_t iova_start_pad = iova_offset(iovad, addr); + struct iommu_iotlb_gather iotlb_gather; + size_t unmapped; + + if ((state->__size & DMA_IOVA_USE_SWIOTLB) || + (!dev_is_dma_coherent(dev) && !(attrs & DMA_ATTR_SKIP_CPU_SYNC))) + iommu_dma_iova_unlink_range_slow(dev, addr, size, dir, attrs); + + iommu_iotlb_gather_init(&iotlb_gather); + iotlb_gather.queued = free_iova && READ_ONCE(cookie->fq_domain); + + size = iova_align(iovad, size + iova_start_pad); + addr -= iova_start_pad; + unmapped = iommu_unmap_fast(domain, addr, size, &iotlb_gather); + WARN_ON(unmapped != size); + + if (!iotlb_gather.queued) + iommu_iotlb_sync(domain, &iotlb_gather); + if (free_iova) + iommu_dma_free_iova(cookie, addr, size, &iotlb_gather); +} + +/** + * dma_iova_unlink - Unlink a range of IOVA space + * @dev: DMA device + * @state: IOVA state + * @offset: offset into the IOVA state to unlink + * @size: size of the buffer + * @dir: DMA direction + * @attrs: attributes of mapping properties + * + * Unlink a range of IOVA space for the given IOVA state. + */ +void dma_iova_unlink(struct device *dev, struct dma_iova_state *state, + size_t offset, size_t size, enum dma_data_direction dir, + unsigned long attrs) +{ + __iommu_dma_iova_unlink(dev, state, offset, size, dir, attrs, false); +} +EXPORT_SYMBOL_GPL(dma_iova_unlink); + +/** + * dma_iova_destroy - Finish a DMA mapping transaction + * @dev: DMA device + * @state: IOVA state + * @mapped_len: number of bytes to unmap + * @dir: DMA direction + * @attrs: attributes of mapping properties + * + * Unlink the IOVA range up to @mapped_len and free the entire IOVA space. The + * range of IOVA from dma_addr to @mapped_len must all be linked, and be the + * only linked IOVA in state. + */ +void dma_iova_destroy(struct device *dev, struct dma_iova_state *state, + size_t mapped_len, enum dma_data_direction dir, + unsigned long attrs) +{ + if (mapped_len) + __iommu_dma_iova_unlink(dev, state, 0, mapped_len, dir, attrs, + true); + else + /* + * We can be here if first call to dma_iova_link() failed and + * there is nothing to unlink, so let's be more clear. + */ + dma_iova_free(dev, state); +} +EXPORT_SYMBOL_GPL(dma_iova_destroy); + void iommu_setup_dma_ops(struct device *dev) { struct iommu_domain *domain = iommu_get_domain_for_dev(dev); diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index 817f11bce7bc..8074a3b5c807 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -313,6 +313,17 @@ static inline bool dma_use_iova(struct dma_iova_state *state) bool dma_iova_try_alloc(struct device *dev, struct dma_iova_state *state, phys_addr_t phys, size_t size); void dma_iova_free(struct device *dev, struct dma_iova_state *state); +void dma_iova_destroy(struct device *dev, struct dma_iova_state *state, + size_t mapped_len, enum dma_data_direction dir, + unsigned long attrs); +int dma_iova_sync(struct device *dev, struct dma_iova_state *state, + size_t offset, size_t size); +int dma_iova_link(struct device *dev, struct dma_iova_state *state, + phys_addr_t phys, size_t offset, size_t size, + enum dma_data_direction dir, unsigned long attrs); +void dma_iova_unlink(struct device *dev, struct dma_iova_state *state, + size_t offset, size_t size, enum dma_data_direction dir, + unsigned long attrs); #else /* CONFIG_IOMMU_DMA */ static inline bool dma_use_iova(struct dma_iova_state *state) { @@ -327,6 +338,27 @@ static inline void dma_iova_free(struct device *dev, struct dma_iova_state *state) { } +static inline void dma_iova_destroy(struct device *dev, + struct dma_iova_state *state, size_t mapped_len, + enum dma_data_direction dir, unsigned long attrs) +{ +} +static inline int dma_iova_sync(struct device *dev, struct dma_iova_state *state, + size_t offset, size_t size) +{ + return -EOPNOTSUPP; +} +static inline int dma_iova_link(struct device *dev, + struct dma_iova_state *state, phys_addr_t phys, size_t offset, + size_t size, enum dma_data_direction dir, unsigned long attrs) +{ + return -EOPNOTSUPP; +} +static inline void dma_iova_unlink(struct device *dev, + struct dma_iova_state *state, size_t offset, size_t size, + enum dma_data_direction dir, unsigned long attrs) +{ +} #endif /* CONFIG_IOMMU_DMA */ #if defined(CONFIG_HAS_DMA) && defined(CONFIG_DMA_NEED_SYNC)