From: Robin Murphy <robin.murphy@arm.com> To: hch@lst.de, m.szyprowski@samsung.com Cc: lorenzo.pieralisi@arm.com, gregkh@linuxfoundation.org, joro@8bytes.org, x86@kernel.org, linux-acpi@vger.kernel.org, iommu@lists.linux-foundation.org, robh+dt@kernel.org, hanjun.guo@linaro.org, sudeep.holla@arm.com, frowand.list@gmail.com, linux-arm-kernel@lists.infradead.org Subject: [PATCH v2 2/7] dma-mapping: Generalise dma_32bit_limit flag Date: Mon, 23 Jul 2018 23:16:07 +0100 [thread overview] Message-ID: <c1720f0181b66f711e4097d85149757b16a7b0a7.1532382222.git.robin.murphy@arm.com> (raw) In-Reply-To: <cover.1532382222.git.robin.murphy@arm.com> Whilst the notion of an upstream DMA restriction is most commonly seen in PCI host bridges saddled with a 32-bit native interface, a more general version of the same issue can exist on complex SoCs where a bus or point-to-point interconnect link from a device's DMA master interface to another component along the path to memory (often an IOMMU) may carry fewer address bits than the interfaces at both ends nominally support. In order to properly deal with this, the first step is to expand the dma_32bit_limit flag into an arbitrary mask. To minimise the impact on existing code, we'll make sure to only consider this new mask valid if set. That makes sense anyway, since a mask of zero would represent DMA not being wired up at all, and that would be better handled by not providing valid ops in the first place. Signed-off-by: Robin Murphy <robin.murphy@arm.com> --- arch/x86/kernel/pci-dma.c | 2 +- include/linux/device.h | 6 +++--- kernel/dma/direct.c | 6 +++--- 3 files changed, 7 insertions(+), 7 deletions(-) diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c index ab5d9dd668d2..c29b0d453db3 100644 --- a/arch/x86/kernel/pci-dma.c +++ b/arch/x86/kernel/pci-dma.c @@ -175,7 +175,7 @@ rootfs_initcall(pci_iommu_init); static int via_no_dac_cb(struct pci_dev *pdev, void *data) { - pdev->dev.dma_32bit_limit = true; + pdev->bus_dma_mask = DMA_BIT_MASK(32); return 0; } diff --git a/include/linux/device.h b/include/linux/device.h index 055a69dbcd18..6d3b000be57e 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -886,6 +886,8 @@ struct dev_links_info { * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all * hardware supports 64-bit addresses for consistent allocations * such descriptors. + * @bus_dma_mask: Mask of an upstream bridge or bus which imposes a smaller DMA + * limit than the device itself supports. * @dma_pfn_offset: offset of DMA memory range relatively of RAM * @dma_parms: A low level driver may set these to teach IOMMU code about * segment limitations. @@ -912,8 +914,6 @@ struct dev_links_info { * @offline: Set after successful invocation of bus type's .offline(). * @of_node_reused: Set if the device-tree node is shared with an ancestor * device. - * @dma_32bit_limit: bridge limited to 32bit DMA even if the device itself - * indicates support for a higher limit in the dma_mask field. * * At the lowest level, every device in a Linux system is represented by an * instance of struct device. The device structure contains the information @@ -967,6 +967,7 @@ struct device { not all hardware supports 64 bit addresses for consistent allocations such descriptors. */ + u64 bus_dma_mask; /* upstream dma_mask constraint */ unsigned long dma_pfn_offset; struct device_dma_parameters *dma_parms; @@ -1002,7 +1003,6 @@ struct device { bool offline_disabled:1; bool offline:1; bool of_node_reused:1; - bool dma_32bit_limit:1; }; static inline struct device *kobj_to_dev(struct kobject *kobj) diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index 8be8106270c2..c2860c5a9e96 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -180,10 +180,10 @@ int dma_direct_supported(struct device *dev, u64 mask) return 0; #endif /* - * Various PCI/PCIe bridges have broken support for > 32bit DMA even - * if the device itself might support it. + * Upstream PCI/PCIe bridges or SoC interconnects may not carry + * as many DMA address bits as the device itself supports. */ - if (dev->dma_32bit_limit && mask > DMA_BIT_MASK(32)) + if (dev->bus_dma_mask && mask > dev->bus_dma_mask) return 0; return 1; } -- 2.17.1.dirty
WARNING: multiple messages have this Message-ID (diff)
From: robin.murphy@arm.com (Robin Murphy) To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v2 2/7] dma-mapping: Generalise dma_32bit_limit flag Date: Mon, 23 Jul 2018 23:16:07 +0100 [thread overview] Message-ID: <c1720f0181b66f711e4097d85149757b16a7b0a7.1532382222.git.robin.murphy@arm.com> (raw) In-Reply-To: <cover.1532382222.git.robin.murphy@arm.com> Whilst the notion of an upstream DMA restriction is most commonly seen in PCI host bridges saddled with a 32-bit native interface, a more general version of the same issue can exist on complex SoCs where a bus or point-to-point interconnect link from a device's DMA master interface to another component along the path to memory (often an IOMMU) may carry fewer address bits than the interfaces at both ends nominally support. In order to properly deal with this, the first step is to expand the dma_32bit_limit flag into an arbitrary mask. To minimise the impact on existing code, we'll make sure to only consider this new mask valid if set. That makes sense anyway, since a mask of zero would represent DMA not being wired up at all, and that would be better handled by not providing valid ops in the first place. Signed-off-by: Robin Murphy <robin.murphy@arm.com> --- arch/x86/kernel/pci-dma.c | 2 +- include/linux/device.h | 6 +++--- kernel/dma/direct.c | 6 +++--- 3 files changed, 7 insertions(+), 7 deletions(-) diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c index ab5d9dd668d2..c29b0d453db3 100644 --- a/arch/x86/kernel/pci-dma.c +++ b/arch/x86/kernel/pci-dma.c @@ -175,7 +175,7 @@ rootfs_initcall(pci_iommu_init); static int via_no_dac_cb(struct pci_dev *pdev, void *data) { - pdev->dev.dma_32bit_limit = true; + pdev->bus_dma_mask = DMA_BIT_MASK(32); return 0; } diff --git a/include/linux/device.h b/include/linux/device.h index 055a69dbcd18..6d3b000be57e 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -886,6 +886,8 @@ struct dev_links_info { * @coherent_dma_mask: Like dma_mask, but for alloc_coherent mapping as not all * hardware supports 64-bit addresses for consistent allocations * such descriptors. + * @bus_dma_mask: Mask of an upstream bridge or bus which imposes a smaller DMA + * limit than the device itself supports. * @dma_pfn_offset: offset of DMA memory range relatively of RAM * @dma_parms: A low level driver may set these to teach IOMMU code about * segment limitations. @@ -912,8 +914,6 @@ struct dev_links_info { * @offline: Set after successful invocation of bus type's .offline(). * @of_node_reused: Set if the device-tree node is shared with an ancestor * device. - * @dma_32bit_limit: bridge limited to 32bit DMA even if the device itself - * indicates support for a higher limit in the dma_mask field. * * At the lowest level, every device in a Linux system is represented by an * instance of struct device. The device structure contains the information @@ -967,6 +967,7 @@ struct device { not all hardware supports 64 bit addresses for consistent allocations such descriptors. */ + u64 bus_dma_mask; /* upstream dma_mask constraint */ unsigned long dma_pfn_offset; struct device_dma_parameters *dma_parms; @@ -1002,7 +1003,6 @@ struct device { bool offline_disabled:1; bool offline:1; bool of_node_reused:1; - bool dma_32bit_limit:1; }; static inline struct device *kobj_to_dev(struct kobject *kobj) diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index 8be8106270c2..c2860c5a9e96 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -180,10 +180,10 @@ int dma_direct_supported(struct device *dev, u64 mask) return 0; #endif /* - * Various PCI/PCIe bridges have broken support for > 32bit DMA even - * if the device itself might support it. + * Upstream PCI/PCIe bridges or SoC interconnects may not carry + * as many DMA address bits as the device itself supports. */ - if (dev->dma_32bit_limit && mask > DMA_BIT_MASK(32)) + if (dev->bus_dma_mask && mask > dev->bus_dma_mask) return 0; return 1; } -- 2.17.1.dirty
next prev parent reply other threads:[~2018-07-23 22:16 UTC|newest] Thread overview: 82+ messages / expand[flat|nested] mbox.gz Atom feed top 2018-07-23 22:16 [PATCH v2 0/7] Stop losing firmware-set DMA masks Robin Murphy 2018-07-23 22:16 ` Robin Murphy 2018-07-23 22:16 ` [PATCH v2 1/7] ACPI/IORT: Support address size limit for root complexes Robin Murphy 2018-07-23 22:16 ` Robin Murphy 2018-07-23 22:16 ` Robin Murphy [this message] 2018-07-23 22:16 ` [PATCH v2 2/7] dma-mapping: Generalise dma_32bit_limit flag Robin Murphy [not found] ` <c1720f0181b66f711e4097d85149757b16a7b0a7.1532382222.git.robin.murphy-5wv7dgnIgG8@public.gmane.org> 2018-07-25 11:29 ` Christoph Hellwig 2018-07-25 11:29 ` Christoph Hellwig 2018-07-27 17:45 ` Grygorii Strashko via iommu 2018-07-27 17:45 ` Grygorii Strashko [not found] ` <7872d914-8ea7-06e4-4a0c-489023e098d6-l0cyMroinI0@public.gmane.org> 2018-07-27 20:11 ` Robin Murphy 2018-07-27 20:11 ` Robin Murphy [not found] ` <5354ef69-c54e-170b-62d4-5110dc60aa8f-5wv7dgnIgG8@public.gmane.org> 2018-07-27 20:41 ` Grygorii Strashko via iommu 2018-07-27 20:41 ` Grygorii Strashko 2018-07-23 22:16 ` [PATCH v2 3/7] ACPI/IORT: Set bus DMA mask as appropriate Robin Murphy 2018-07-23 22:16 ` Robin Murphy [not found] ` <07cbf8f77fac552dca9b4c85a9d3bd8ed5a4cd29.1532382222.git.robin.murphy-5wv7dgnIgG8@public.gmane.org> 2018-07-25 11:29 ` Christoph Hellwig 2018-07-25 11:29 ` Christoph Hellwig 2018-07-25 13:16 ` Lorenzo Pieralisi 2018-07-25 13:16 ` Lorenzo Pieralisi 2018-07-23 22:16 ` [PATCH v2 4/7] of/device: " Robin Murphy 2018-07-23 22:16 ` Robin Murphy [not found] ` <cc56f074b8da7e03a187b2363b1f2c2955d62c1c.1532382222.git.robin.murphy-5wv7dgnIgG8@public.gmane.org> 2018-07-25 11:30 ` Christoph Hellwig 2018-07-25 11:30 ` Christoph Hellwig 2018-07-23 22:16 ` [PATCH v2 5/7] iommu/dma: Respect bus DMA limit for IOVAs Robin Murphy 2018-07-23 22:16 ` Robin Murphy [not found] ` <d370670edae9c9c537a5280c5e7c96bf3ec7ed8f.1532382222.git.robin.murphy-5wv7dgnIgG8@public.gmane.org> 2018-07-26 8:58 ` Christoph Hellwig 2018-07-26 8:58 ` Christoph Hellwig 2018-07-23 22:16 ` [PATCH v2 6/7] ACPI/IORT: Don't set default coherent DMA mask Robin Murphy 2018-07-23 22:16 ` Robin Murphy [not found] ` <3525869e8e7530128bf9718ae8af7d7564b3c684.1532382222.git.robin.murphy-5wv7dgnIgG8@public.gmane.org> 2018-07-25 15:27 ` Lorenzo Pieralisi 2018-07-25 15:27 ` Lorenzo Pieralisi 2018-07-25 15:43 ` Robin Murphy 2018-07-25 15:43 ` Robin Murphy 2018-07-23 22:16 ` [PATCH v2 7/7] OF: " Robin Murphy 2018-07-23 22:16 ` Robin Murphy [not found] ` <66c08e4df2032fde82a2f97544f41fd3a2f24a94.1532382222.git.robin.murphy-5wv7dgnIgG8@public.gmane.org> 2018-07-26 23:52 ` Grygorii Strashko via iommu 2018-07-26 23:52 ` Grygorii Strashko 2018-07-27 0:22 ` Grygorii Strashko 2018-07-27 0:22 ` Grygorii Strashko [not found] ` <92d6b010-b5c0-fc59-0668-5b455e26c912-l0cyMroinI0@public.gmane.org> 2018-07-27 11:36 ` Robin Murphy 2018-07-27 11:36 ` Robin Murphy 2018-07-27 17:34 ` Grygorii Strashko 2018-07-27 17:34 ` Grygorii Strashko [not found] ` <108a6254-1257-5daf-deaa-69bc4db2ec77-l0cyMroinI0@public.gmane.org> 2018-07-27 19:46 ` Robin Murphy 2018-07-27 19:46 ` Robin Murphy [not found] ` <c7a9c7ae-1f4a-af9d-df78-1f48bb5c28a5-5wv7dgnIgG8@public.gmane.org> 2018-07-27 18:13 ` Russell King - ARM Linux 2018-07-27 18:13 ` Russell King - ARM Linux [not found] ` <20180727181302.GC17271-l+eeeJia6m9URfEZ8mYm6t73F7V6hmMc@public.gmane.org> 2018-07-27 18:45 ` Grygorii Strashko via iommu 2018-07-27 18:45 ` Grygorii Strashko [not found] ` <affa2718-5f3a-7439-db25-ce171a99414a-l0cyMroinI0@public.gmane.org> 2018-07-27 20:42 ` Robin Murphy 2018-07-27 20:42 ` Robin Murphy 2018-07-27 19:29 ` Robin Murphy 2018-07-27 19:29 ` Robin Murphy 2018-07-26 23:45 ` [PATCH v2 0/7] Stop losing firmware-set DMA masks Grygorii Strashko 2018-07-26 23:45 ` Grygorii Strashko [not found] ` <c73bc8d2-b745-ff31-1949-7a59ab04ede6-l0cyMroinI0@public.gmane.org> 2018-07-27 10:55 ` Robin Murphy 2018-07-27 10:55 ` Robin Murphy [not found] ` <8b8ac841-5c4c-ae27-21d5-d7aaaf4c277c-5wv7dgnIgG8@public.gmane.org> 2018-07-27 17:22 ` Grygorii Strashko via iommu 2018-07-27 17:22 ` Grygorii Strashko [not found] ` <cover.1532382222.git.robin.murphy-5wv7dgnIgG8@public.gmane.org> 2018-07-25 11:31 ` Christoph Hellwig 2018-07-25 11:31 ` Christoph Hellwig [not found] ` <20180725113122.GD24736-jcswGhMUV9g@public.gmane.org> 2018-07-25 12:11 ` Joerg Roedel 2018-07-25 12:11 ` Joerg Roedel 2018-07-25 12:12 ` Robin Murphy 2018-07-25 12:12 ` Robin Murphy [not found] ` <5e036ade-db0b-f628-a4a0-6d014d1d76c8-5wv7dgnIgG8@public.gmane.org> 2018-07-25 12:17 ` Will Deacon 2018-07-25 12:17 ` Will Deacon 2018-07-25 13:58 ` Ard Biesheuvel 2018-07-25 13:58 ` Ard Biesheuvel 2018-07-26 9:00 ` Christoph Hellwig 2018-07-26 9:00 ` Christoph Hellwig 2018-07-29 12:32 ` Arnd Bergmann 2018-07-29 12:32 ` Arnd Bergmann [not found] ` <CAK8P3a3HDJ6svNN_cwvegxu20yNv8+tvc0D1A6Ooeq8agawbFg-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org> 2018-07-31 11:24 ` Robin Murphy 2018-07-31 11:24 ` Robin Murphy [not found] ` <1ccccc4b-7d4c-a3ee-23a2-f108916705e9-5wv7dgnIgG8@public.gmane.org> 2018-08-06 10:01 ` Arnd Bergmann 2018-08-06 10:01 ` Arnd Bergmann [not found] ` <CAK8P3a3ZcOeHMR_qFnsBdXED+2X8_AEMKoS5MeAQhbapbGmm9w-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org> 2018-08-06 12:13 ` Christoph Hellwig 2018-08-06 12:13 ` Christoph Hellwig [not found] ` <20180806121334.GA5340-jcswGhMUV9g@public.gmane.org> 2018-08-06 12:13 ` Arnd Bergmann 2018-08-06 12:13 ` Arnd Bergmann
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