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2020-10-22Merge tag 'pci-v5.10-changes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI updates from Bjorn Helgaas: "Enumeration: - Print IRQ number used by PCIe Link Bandwidth Notification (Dongdong Liu) - Add schedule point in pci_read_config() to reduce max latency (Jiang Biao) - Add Kconfig options for MPS/MRRS strategy (Jim Quinlan) Resource management: - Fix pci_iounmap() memory leak when !CONFIG_GENERIC_IOMAP (Lorenzo Pieralisi) PCIe native device hotplug: - Reduce noisiness on hot removal (Lukas Wunner) Power management: - Revert "PCI/PM: Apply D2 delay as milliseconds, not microseconds" that was done on the basis of spec typo (Bjorn Helgaas) - Rename pci_dev.d3_delay to d3hot_delay to remove D3hot/D3cold ambiguity (Krzysztof Wilczyński) - Remove unused pcibios_pm_ops (Vaibhav Gupta) IOMMU: - Enable Translation Blocking for external devices to harden against DMA attacks (Rajat Jain) Error handling: - Add an ACPI APEI notifier chain for vendor CPER records to enable device-specific error handling (Shiju Jose) ASPM: - Remove struct aspm_register_info to simplify code (Saheed O. Bolarinwa) Amlogic Meson PCIe controller driver: - Build as module by default (Kevin Hilman) Ampere Altra PCIe controller driver: - Add MCFG quirk to work around non-standard ECAM implementation (Tuan Phan) Broadcom iProc PCIe controller driver: - Set affinity mask on MSI interrupts (Mark Tomlinson) Broadcom STB PCIe controller driver: - Make PCIE_BRCMSTB depend on ARCH_BRCMSTB (Jim Quinlan) - Add DT bindings for more Brcmstb chips (Jim Quinlan) - Add bcm7278 register info (Jim Quinlan) - Add bcm7278 PERST# support (Jim Quinlan) - Add suspend and resume pm_ops (Jim Quinlan) - Add control of rescal reset (Jim Quinlan) - Set additional internal memory DMA viewport sizes (Jim Quinlan) - Accommodate MSI for older chips (Jim Quinlan) - Set bus max burst size by chip type (Jim Quinlan) - Add support for bcm7211, bcm7216, bcm7445, bcm7278 (Jim Quinlan) Freescale i.MX6 PCIe controller driver: - Use dev_err_probe() to reduce redundant messages (Anson Huang) Freescale Layerscape PCIe controller driver: - Enforce 4K DMA buffer alignment in endpoint test (Hou Zhiqiang) - Add DT compatible strings for ls1088a, ls2088a (Xiaowei Bao) - Add endpoint support for ls1088a, ls2088a (Xiaowei Bao) - Add endpoint test support for lS1088a (Xiaowei Bao) - Add MSI-X support for ls1088a (Xiaowei Bao) HiSilicon HIP PCIe controller driver: - Handle HIP-specific errors via ACPI APEI (Yicong Yang) HiSilicon Kirin PCIe controller driver: - Return -EPROBE_DEFER if the GPIO isn't ready (Bean Huo) Intel VMD host bridge driver: - Factor out physical offset, bus offset, IRQ domain, IRQ allocation (Jon Derrick) - Use generic PCI PM correctly (Jon Derrick) Marvell Aardvark PCIe controller driver: - Fix compilation on s390 (Pali Rohár) - Implement driver 'remove' function and allow to build it as module (Pali Rohár) - Move PCIe reset card code to advk_pcie_train_link() (Pali Rohár) - Convert mvebu a3700 internal SMCC firmware return codes to errno (Pali Rohár) - Fix initialization with old Marvell's Arm Trusted Firmware (Pali Rohár) Microsoft Hyper-V host bridge driver: - Fix hibernation in case interrupts are not re-created (Dexuan Cui) NVIDIA Tegra PCIe controller driver: - Stop checking return value of debugfs_create() functions (Greg Kroah-Hartman) - Convert to use DEFINE_SEQ_ATTRIBUTE macro (Liu Shixin) Qualcomm PCIe controller driver: - Reset PCIe to work around Qsdk U-Boot issue (Ansuel Smith) Renesas R-Car PCIe controller driver: - Add DT documentation for r8a774a1, r8a774b1, r8a774e1 endpoints (Lad Prabhakar) - Add RZ/G2M, RZ/G2N, RZ/G2H IDs to endpoint test (Lad Prabhakar) - Add DT support for r8a7742 (Lad Prabhakar) Socionext UniPhier Pro5 controller driver: - Add DT descriptions of iATU register (host and endpoint) (Kunihiko Hayashi) Synopsys DesignWare PCIe controller driver: - Add link up check in dw_child_pcie_ops.map_bus() (racy, but seems unavoidable) (Hou Zhiqiang) - Fix endpoint Header Type check so multi-function devices work (Hou Zhiqiang) - Skip PCIE_MSI_INTR0* programming if MSI is disabled (Jisheng Zhang) - Stop leaking MSI page in suspend/resume (Jisheng Zhang) - Add common iATU register support instead of keystone-specific code (Kunihiko Hayashi) - Major config space access and other cleanups in dwc core and drivers that use it (al, exynos, histb, imx6, intel-gw, keystone, kirin, meson, qcom, tegra) (Rob Herring) - Add multiple PFs support for endpoint (Xiaowei Bao) - Add MSI-X doorbell mode in endpoint mode (Xiaowei Bao) Miscellaneous: - Use fallthrough pseudo-keyword (Gustavo A. R. Silva) - Fix "0 used as NULL pointer" warnings (Gustavo Pimentel) - Fix "cast truncates bits from constant value" warnings (Gustavo Pimentel) - Remove redundant zeroing for sg_init_table() (Julia Lawall) - Use scnprintf(), not snprintf(), in sysfs "show" functions (Krzysztof Wilczyński) - Remove unused assignments (Krzysztof Wilczyński) - Fix "0 used as NULL pointer" warning (Krzysztof Wilczyński) - Simplify bool comparisons (Krzysztof Wilczyński) - Use for_each_child_of_node() and for_each_node_by_name() (Qinglang Miao) - Simplify return expressions (Qinglang Miao)" * tag 'pci-v5.10-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (147 commits) PCI: vmd: Update VMD PM to correctly use generic PCI PM PCI: vmd: Create IRQ allocation helper PCI: vmd: Create IRQ Domain configuration helper PCI: vmd: Create bus offset configuration helper PCI: vmd: Create physical offset helper PCI: v3-semi: Remove unneeded break PCI: dwc: Add link up check in dw_child_pcie_ops.map_bus() PCI/ASPM: Remove struct pcie_link_state.l1ss PCI/ASPM: Remove struct aspm_register_info.l1ss_cap PCI/ASPM: Pass L1SS Capabilities value, not struct aspm_register_info PCI/ASPM: Remove struct aspm_register_info.l1ss_ctl1 PCI/ASPM: Remove struct aspm_register_info.l1ss_ctl2 (unused) PCI/ASPM: Remove struct aspm_register_info.l1ss_cap_ptr PCI/ASPM: Remove struct aspm_register_info.latency_encoding PCI/ASPM: Remove struct aspm_register_info.enabled PCI/ASPM: Remove struct aspm_register_info.support PCI/ASPM: Use 'parent' and 'child' for readability PCI/ASPM: Move LTR path check to where it's used PCI/ASPM: Move pci_clear_and_set_dword() earlier PCI: dwc: Fix MSI page leakage in suspend/resume ...
2020-10-13mm/memremap_pages: support multiple ranges per invocationDan Williams
In support of device-dax growing the ability to front physically dis-contiguous ranges of memory, update devm_memremap_pages() to track multiple ranges with a single reference counter and devm instance. Convert all [devm_]memremap_pages() users to specify the number of ranges they are mapping in their 'struct dev_pagemap' instance. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Paul Mackerras <paulus@ozlabs.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Ben Skeggs <bskeggs@redhat.com> Cc: David Airlie <airlied@linux.ie> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Juergen Gross <jgross@suse.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: "Jérôme Glisse" <jglisse@redhat.co Cc: Andy Lutomirski <luto@kernel.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brice Goglin <Brice.Goglin@inria.fr> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Hulk Robot <hulkci@huawei.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jason Gunthorpe <jgg@mellanox.com> Cc: Jason Yan <yanaijie@huawei.com> Cc: Jeff Moyer <jmoyer@redhat.com> Cc: "Jérôme Glisse" <jglisse@redhat.com> Cc: Jia He <justin.he@arm.com> Cc: Joao Martins <joao.m.martins@oracle.com> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: kernel test robot <lkp@intel.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: Will Deacon <will@kernel.org> Link: https://lkml.kernel.org/r/159643103789.4062302.18426128170217903785.stgit@dwillia2-desk3.amr.corp.intel.com Link: https://lkml.kernel.org/r/160106116293.30709.13350662794915396198.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13mm/memremap_pages: convert to 'struct range'Dan Williams
The 'struct resource' in 'struct dev_pagemap' is only used for holding resource span information. The other fields, 'name', 'flags', 'desc', 'parent', 'sibling', and 'child' are all unused wasted space. This is in preparation for introducing a multi-range extension of devm_memremap_pages(). The bulk of this change is unwinding all the places internal to libnvdimm that used 'struct resource' unnecessarily, and replacing instances of 'struct dev_pagemap'.res with 'struct dev_pagemap'.range. P2PDMA had a minor usage of the resource flags field, but only to report failures with "%pR". That is replaced with an open coded print of the range. [dan.carpenter@oracle.com: mm/hmm/test: use after free in dmirror_allocate_chunk()] Link: https://lkml.kernel.org/r/20200926121402.GA7467@kadam Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> [xen] Cc: Paul Mackerras <paulus@ozlabs.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Ben Skeggs <bskeggs@redhat.com> Cc: David Airlie <airlied@linux.ie> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Juergen Gross <jgross@suse.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: "Jérôme Glisse" <jglisse@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brice Goglin <Brice.Goglin@inria.fr> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Hulk Robot <hulkci@huawei.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jason Gunthorpe <jgg@mellanox.com> Cc: Jason Yan <yanaijie@huawei.com> Cc: Jeff Moyer <jmoyer@redhat.com> Cc: Jia He <justin.he@arm.com> Cc: Joao Martins <joao.m.martins@oracle.com> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: kernel test robot <lkp@intel.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: Will Deacon <will@kernel.org> Link: https://lkml.kernel.org/r/159643103173.4062302.768998885691711532.stgit@dwillia2-desk3.amr.corp.intel.com Link: https://lkml.kernel.org/r/160106115761.30709.13539840236873663620.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-09-30PCI/P2PDMA: Drop double zeroing for sg_init_table()Julia Lawall
sg_init_table() zeroes its first argument, so the allocation of that argument doesn't have to. The semantic patch that makes this change is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ expression x; @@ x = - kzalloc + kmalloc (...) ... sg_init_table(x,...) // </smpl> Link: https://lore.kernel.org/r/1600601186-7420-15-git-send-email-Julia.Lawall@inria.fr Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2020-09-01PCI: Use scnprintf(), not snprintf(), in sysfs "show" functionsKrzysztof Wilczyński
Sysfs "show" methods should return the number of bytes printed into the buffer. This is the return value of scnprintf() [1]. snprintf(buf, size, ...) prints at most "size" bytes into "buf", but returns the number of bytes that *would* be printed if "buf" were large enough. Replace use of snprintf() with scnprintf(). No functional change intended. Related: https://patchwork.kernel.org/patch/9946759/#20969333 https://lwn.net/Articles/69419 [1] Documentation/filesystems/sysfs.rst [bhelgaas: squashed, commit log] Suggested-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://lore.kernel.org/r/20200824233918.26306-2-kw@linux.com Link: https://lore.kernel.org/r/20200824233918.26306-3-kw@linux.com Link: https://lore.kernel.org/r/20200824233918.26306-4-kw@linux.com Signed-off-by: Krzysztof Wilczyński <kw@linux.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2020-08-17PCI/P2PDMA: Fix build without DMA opsChristoph Hellwig
My commit to make DMA ops support optional missed the reference in the p2pdma code. And while the build bot didn't manage to find a config where this can happen, Matthew did. Fix this by replacing two IS_ENABLED checks with ifdefs. Fixes: 2f9237d4f6df ("dma-mapping: make support for dma ops optional") Link: https://lore.kernel.org/r/20200810124843.1532738-1-hch@lst.de Reported-by: Matthew Wilcox <willy@infradead.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
2020-08-05Merge branch 'pci/peer-to-peer'Bjorn Helgaas
- Allow P2PDMA on AMD Zen and newer CPUs (Logan Gunthorpe) * pci/peer-to-peer: PCI/P2PDMA: Allow P2PDMA on AMD Zen and newer CPUs
2020-07-30PCI/P2PDMA: Allow P2PDMA on AMD Zen and newer CPUsLogan Gunthorpe
Allow P2PDMA if the CPU vendor is AMD and family is 0x17 (Zen) or greater. [bhelgaas: commit log, simplify #if/#else/#endif] Link: https://lore.kernel.org/r/20200729231844.4653-1-logang@deltatee.com Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Cc: Christian König <christian.koenig@amd.com> Cc: Huang Rui <ray.huang@amd.com>
2020-07-10PCI: Cache ACS capability offset in deviceRajat Jain
Currently the ACS capability is being looked up at a number of places. Read and store it once at enumeration so that it can be used by all later. No functional change intended. Link: https://lore.kernel.org/r/20200707224604.3737893-2-rajatja@google.com Signed-off-by: Rajat Jain <rajatja@google.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2020-04-23PCI/P2PDMA: Add AMD Zen Raven and Renoir Root Ports to whitelistAlex Deucher
According to the hardware architect, pre-Zen parts support p2p writes and Zen parts support both p2p reads and writes. Add entries for Zen parts Raven (0x15d0) and Renoir (0x1630). Link: https://lore.kernel.org/r/20200406194201.846411-1-alexander.deucher@amd.com Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Christian König <christian.koenig@amd.com> Acked-by: Huang Rui <ray.huang@amd.com>
2020-03-18PCI/P2PDMA: Add Intel Sky Lake-E Root Ports B, C, D to the whitelistAndrew Maier
Add the three remaining Intel Sky Lake-E host Root Ports to the whitelist of p2pdma. P2P has been tested and is working on this system. Link: https://lore.kernel.org/r/20200207221219.4309-1-andrew.maier@eideticom.com Signed-off-by: Andrew Maier <andrew.maier@eideticom.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
2019-12-10PCI/P2PDMA: Add Intel SkyLake-E to the whitelistArmen Baloyan
Intel SkyLake-E was successfully tested for p2pdma transactions spanning over a host bridge and PCI bridge with IOMMU on. Add it to the whitelist. Link: https://lore.kernel.org/r/1575669165-31697-1-git-send-email-abaloyan@gigaio.com Signed-off-by: Armen Baloyan <abaloyan@gigaio.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
2019-08-16PCI/P2PDMA: Update pci_p2pdma_distance_many() documentationLogan Gunthorpe
The comment describing pci_p2pdma_distance_many() still referred to the devices being behind the same root port. This no longer applies so reword the documentation. Link: https://lore.kernel.org/r/20190730163545.4915-15-logang@deltatee.com Link: https://lore.kernel.org/r/20190812173048.9186-15-logang@deltatee.com Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-08-16PCI/P2PDMA: Allow IOMMU for host bridge whitelistLogan Gunthorpe
Now that we map the requests correctly we can remove the iommu_present() restriction. Link: https://lore.kernel.org/r/20190730163545.4915-14-logang@deltatee.com Link: https://lore.kernel.org/r/20190812173048.9186-14-logang@deltatee.com Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-08-16PCI/P2PDMA: dma_map() requests that traverse the host bridgeLogan Gunthorpe
Any requests that traverse the host bridge will need to be mapped into the IOMMU, so call dma_map_sg() inside pci_p2pdma_map_sg() when appropriate. Similarly, call dma_unmap_sg() inside pci_p2pdma_unmap_sg(). Link: https://lore.kernel.org/r/20190730163545.4915-13-logang@deltatee.com Link: https://lore.kernel.org/r/20190812173048.9186-13-logang@deltatee.com Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-08-16PCI/P2PDMA: Store mapping method in an xarrayLogan Gunthorpe
When upstream_bridge_distance() is called, store the method required to map the DMA transfers in an xarray so it can be looked up efficiently on the hot path in pci_p2pdma_map_sg(). Link: https://lore.kernel.org/r/20190730163545.4915-12-logang@deltatee.com Link: https://lore.kernel.org/r/20190812173048.9186-12-logang@deltatee.com Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-08-16PCI/P2PDMA: Factor out __pci_p2pdma_map_sg()Logan Gunthorpe
Factor out the bus-only mapping into its own static function. No functional changes. The original pci_p2pdma_map_sg_attrs() will be used to decide whether this is an appropriate way to map. Link: https://lore.kernel.org/r/20190730163545.4915-11-logang@deltatee.com Link: https://lore.kernel.org/r/20190812173048.9186-11-logang@deltatee.com Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-08-16PCI/P2PDMA: Introduce pci_p2pdma_unmap_sg()Logan Gunthorpe
Add pci_p2pdma_unmap_sg() to the two places that call pci_p2pdma_map_sg(). This is a prep patch to introduce correct mappings for p2pdma transactions that go through the root complex. Link: https://lore.kernel.org/r/20190730163545.4915-10-logang@deltatee.com Link: https://lore.kernel.org/r/20190812173048.9186-10-logang@deltatee.com Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-08-16PCI/P2PDMA: Add attrs argument to pci_p2pdma_map_sg()Logan Gunthorpe
This is to match the dma_map_sg() API which this function will have to call in an future patch. Add a pci_p2pdma_map_sg_attrs() function and helper to call it with no attributes just like the dma_map_sg() function. Link: https://lore.kernel.org/r/20190730163545.4915-9-logang@deltatee.com Link: https://lore.kernel.org/r/20190812173048.9186-9-logang@deltatee.com Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-08-16PCI/P2PDMA: Whitelist some Intel host bridgesLogan Gunthorpe
Intel devices do not have good support for P2P requests that span different host bridges as the transactions will cross the QPI/UPI bus and this does not perform well. Therefore, enable support for these devices only if the host bridges match. Add Intel devices that have been tested and are known to work. There are likely many others out there that will need to be tested and added. Link: https://lore.kernel.org/r/20190730163545.4915-8-logang@deltatee.com Link: https://lore.kernel.org/r/20190812173048.9186-8-logang@deltatee.com Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-08-16PCI/P2PDMA: Factor out host_bridge_whitelist()Logan Gunthorpe
Push both PCI devices into the whitelist checking function seeing some hardware will require us ensuring they are on the same host bridge. At the same time we rename root_complex_whitelist() to host_bridge_whitelist() to match the terminology used in the code. Link: https://lore.kernel.org/r/20190730163545.4915-7-logang@deltatee.com Link: https://lore.kernel.org/r/20190812173048.9186-7-logang@deltatee.com Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-08-16PCI/P2PDMA: Apply host bridge whitelist for ACSLogan Gunthorpe
When a P2PDMA transfer is rejected due to ACS being set, we can also check the whitelist and allow the transactions. Do this by pushing the whitelist check into the upstream_bridge_distance() function. Link: https://lore.kernel.org/r/20190730163545.4915-6-logang@deltatee.com Link: https://lore.kernel.org/r/20190812173048.9186-6-logang@deltatee.com Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Christian König <christian.koenig@amd.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-08-16PCI/P2PDMA: Factor out __upstream_bridge_distance()Logan Gunthorpe
This is a prep patch to create a second level helper. There are no functional changes. The root complex whitelist code will be moved into this function in a subsequent patch. Link: https://lore.kernel.org/r/20190730163545.4915-5-logang@deltatee.com Link: https://lore.kernel.org/r/20190812173048.9186-5-logang@deltatee.com Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Christian König <christian.koenig@amd.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-08-16PCI/P2PDMA: Add constants for map type results to upstream_bridge_distance()Logan Gunthorpe
Add constant flags to indicate how two devices will be mapped or if they are unsupported. upstream_bridge_distance() will now return the mapping type and the distance in a passed-by-reference argument. This helps annotate the code better, but the main reason is so we can use the information to store the required mapping method in an xarray. Link: https://lore.kernel.org/r/20190730163545.4915-4-logang@deltatee.com Link: https://lore.kernel.org/r/20190812173048.9186-4-logang@deltatee.com Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Christian König <christian.koenig@amd.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-08-16PCI/P2PDMA: Add provider's pci_dev to pci_p2pdma_pagemap structLogan Gunthorpe
The provider will be needed to figure out how to map a device. Link: https://lore.kernel.org/r/20190730163545.4915-3-logang@deltatee.com Link: https://lore.kernel.org/r/20190812173048.9186-3-logang@deltatee.com Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-08-16PCI/P2PDMA: Introduce private pagemap structureLogan Gunthorpe
Move the PCI bus offset from the generic dev_pagemap structure to a specific pci_p2pdma_pagemap structure. This structure will grow in subsequent patches. Link: https://lore.kernel.org/r/20190730163545.4915-2-logang@deltatee.com Link: https://lore.kernel.org/r/20190812173048.9186-2-logang@deltatee.com Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-07-15Merge tag 'pci-v5.3-changes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI updates from Bjorn Helgaas: "Enumeration changes: - Evaluate PCI Boot Configuration _DSM to learn if firmware wants us to preserve its resource assignments (Benjamin Herrenschmidt) - Simplify resource distribution (Nicholas Johnson) - Decode 32 GT/s link speed (Gustavo Pimentel) Virtualization: - Fix incorrect caching of VF config space size (Alex Williamson) - Fix VF driver probing sysfs knobs (Alex Williamson) Peer-to-peer DMA: - Fix dma_virt_ops check (Logan Gunthorpe) Altera host bridge driver: - Allow building as module (Ley Foon Tan) Armada 8K host bridge driver: - add PHYs support (Miquel Raynal) DesignWare host bridge driver: - Export APIs to support removable loadable module (Vidya Sagar) - Enable Relaxed Ordering erratum workaround only on Tegra20 & Tegra30 (Vidya Sagar) Hyper-V host bridge driver: - Fix use-after-free in eject (Dexuan Cui) Mobiveil host bridge driver: - Clean up and fix many issues, including non-identify mapped windows, 64-bit windows, multi-MSI, class code, INTx clearing (Hou Zhiqiang) Qualcomm host bridge driver: - Use clk bulk API for 2.4.0 controllers (Bjorn Andersson) - Add QCS404 support (Bjorn Andersson) - Assert PERST for at least 100ms (Niklas Cassel) R-Car host bridge driver: - Add r8a774a1 DT support (Biju Das) Tegra host bridge driver: - Add support for Gen2, opportunistic UpdateFC and ACK (PCIe protocol details) AER, GPIO-based PERST# (Manikanta Maddireddy) - Fix many issues, including power-on failure cases, interrupt masking in suspend, UPHY settings, AFI dynamic clock gating, pending DLL transactions (Manikanta Maddireddy) Xilinx host bridge driver: - Fix NWL Multi-MSI programming (Bharat Kumar Gogada) Endpoint support: - Fix 64bit BAR support (Alan Mikhak) - Fix pcitest build issues (Alan Mikhak, Andy Shevchenko) Bug fixes: - Fix NVIDIA GPU multi-function power dependencies (Abhishek Sahu) - Fix NVIDIA GPU HDA enablement issue (Lukas Wunner) - Ignore lockdep for sysfs "remove" (Marek Vasut) Misc: - Convert docs to reST (Changbin Du, Mauro Carvalho Chehab)" * tag 'pci-v5.3-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (107 commits) PCI: Enable NVIDIA HDA controllers tools: PCI: Fix installation when `make tools/pci_install` PCI: dwc: pci-dra7xx: Fix compilation when !CONFIG_GPIOLIB PCI: Fix typos and whitespace errors PCI: mobiveil: Fix INTx interrupt clearing in mobiveil_pcie_isr() PCI: mobiveil: Fix infinite-loop in the INTx handling function PCI: mobiveil: Move PCIe PIO enablement out of inbound window routine PCI: mobiveil: Add upper 32-bit PCI base address setup in inbound window PCI: mobiveil: Add upper 32-bit CPU base address setup in outbound window PCI: mobiveil: Mask out hardcoded bits in inbound/outbound windows setup PCI: mobiveil: Clear the control fields before updating it PCI: mobiveil: Add configured inbound windows counter PCI: mobiveil: Fix the valid check for inbound and outbound windows PCI: mobiveil: Clean-up program_{ib/ob}_windows() PCI: mobiveil: Remove an unnecessary return value check PCI: mobiveil: Fix error return values PCI: mobiveil: Refactor the MEM/IO outbound window initialization PCI: mobiveil: Make some register updates more readable PCI: mobiveil: Reformat the code for readability dt-bindings: PCI: mobiveil: Change gpio_slave and apb_csr to optional ...
2019-07-12Merge branch 'pci/trivial'Bjorn Helgaas
- Fix typos and whitespace errors (Bjorn Helgaas) * pci/trivial: PCI: Fix typos and whitespace errors
2019-07-09PCI: Fix typos and whitespace errorsBjorn Helgaas
Fix typos in drivers/pci. Comment and whitespace changes only. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
2019-07-02PCI/P2PDMA: Fix missing check for dma_virt_opsLogan Gunthorpe
Drivers that use dma_virt_ops were meant to be rejected when testing compatibility for P2PDMA. This check got inadvertently dropped in one of the later versions of the original patchset, so add it back. Fixes: 52916982af48 ("PCI/P2PDMA: Support peer-to-peer memory") Link: https://lore.kernel.org/r/20190702173544.21950-1-logang@deltatee.com Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2019-07-02PCI/P2PDMA: use the dev_pagemap internal refcountChristoph Hellwig
The functionality is identical to the one currently open coded in p2pdma.c. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Tested-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-07-02memremap: pass a struct dev_pagemap to ->kill and ->cleanupChristoph Hellwig
Passing the actual typed structure leads to more understandable code vs just passing the ref member. Reported-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Jason Gunthorpe <jgg@mellanox.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Tested-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-07-02memremap: move dev_pagemap callbacks into a separate structureChristoph Hellwig
The dev_pagemap is a growing too many callbacks. Move them into a separate ops structure so that they are not duplicated for multiple instances, and an attacker can't easily overwrite them. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Jason Gunthorpe <jgg@mellanox.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Tested-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-06-22Merge tag 'pci-v5.2-fixes-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI fix from Bjorn Helgaas: "If an IOMMU is present, ignore the P2PDMA whitelist we added for v5.2 because we don't yet know how to support P2PDMA in that case (Logan Gunthorpe)" * tag 'pci-v5.2-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: PCI/P2PDMA: Ignore root complex whitelist when an IOMMU is present
2019-06-19PCI/P2PDMA: Ignore root complex whitelist when an IOMMU is presentLogan Gunthorpe
Presently, there is no path to DMA map P2PDMA memory, so if a TLP targeting this memory hits the root complex and an IOMMU is present, the IOMMU will reject the transaction, even if the RC would support P2PDMA. So until the kernel knows to map these DMA addresses in the IOMMU, we should not enable the whitelist when an IOMMU is present. Link: https://lore.kernel.org/linux-pci/20190522201252.2997-1-logang@deltatee.com/ Fixes: 0f97da831026 ("PCI/P2PDMA: Allow P2P DMA between any devices under AMD ZEN Root Complex") Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: Christoph Hellwig <hch@lst.de>
2019-06-13mm/devm_memremap_pages: fix final page put raceDan Williams
Logan noticed that devm_memremap_pages_release() kills the percpu_ref drops all the page references that were acquired at init and then immediately proceeds to unplug, arch_remove_memory(), the backing pages for the pagemap. If for some reason device shutdown actually collides with a busy / elevated-ref-count page then arch_remove_memory() should be deferred until after that reference is dropped. As it stands the "wait for last page ref drop" happens *after* devm_memremap_pages_release() returns, which is obviously too late and can lead to crashes. Fix this situation by assigning the responsibility to wait for the percpu_ref to go idle to devm_memremap_pages() with a new ->cleanup() callback. Implement the new cleanup callback for all devm_memremap_pages() users: pmem, devdax, hmm, and p2pdma. Link: http://lkml.kernel.org/r/155727339156.292046.5432007428235387859.stgit@dwillia2-desk3.amr.corp.intel.com Fixes: 41e94a851304 ("add devm_memremap_pages") Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reported-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: "Jérôme Glisse" <jglisse@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-06-13PCI/P2PDMA: track pgmap references per resource, not globallyDan Williams
In preparation for fixing a race between devm_memremap_pages_release() and the final put of a page from the device-page-map, allocate a percpu-ref per p2pdma resource mapping. Link: http://lkml.kernel.org/r/155727338646.292046.9922678317501435597.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Jérôme Glisse" <jglisse@redhat.com> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-06-13PCI/P2PDMA: fix the gen_pool_add_virt() failure pathDan Williams
The pci_p2pdma_add_resource() implementation immediately frees the pgmap if gen_pool_add_virt() fails. However, that means that when @dev triggers a devres release devm_memremap_pages_release() will crash trying to access the freed @pgmap. Use the new devm_memunmap_pages() to manually free the mapping in the error path. Link: http://lkml.kernel.org/r/155727337603.292046.13101332703665246702.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Fixes: 52916982af48 ("PCI/P2PDMA: Support peer-to-peer memory") Reviewed-by: Ira Weiny <ira.weiny@intel.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Jérôme Glisse" <jglisse@redhat.com> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-01PCI/P2PDMA: Allow P2P DMA between any devices under AMD ZEN Root ComplexChristian König
The PCI specs say that peer-to-peer DMA should be supported between any two devices that have a common upstream PCI-to-PCI bridge. But devices under different Root Ports don't share a common upstream bridge, and PCIe r4.0, sec 1.3.1, says routing peer-to-peer transactions between Root Ports in the same Root Complex is optional. Many Root Complexes, including AMD ZEN, *do* support peer-to-peer DMA even between Root Ports. Add a whitelist and allow peer-to-peer DMA if both participants are attached to a Root Complex known to support it. Link: https://lore.kernel.org/linux-pci/20190418115859.2394-1-christian.koenig@amd.com Signed-off-by: Christian König <christian.koenig@amd.com> [bhelgaas: changelog] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
2019-01-05Merge tag 'pci-v4.21-changes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI updates from Bjorn Helgaas: - Remove unused lists from ASPM pcie_link_state (Frederick Lawler) - Fix Broadcom CNB20LE host bridge unintended sign extension (Colin Ian King) - Expand Kconfig "PF" acronyms (Randy Dunlap) - Update MAINTAINERS for arch/x86/kernel/early-quirks.c (Bjorn Helgaas) - Add missing include to drivers/pci.h (Alexandru Gagniuc) - Override Synopsys USB 3.x HAPS device class so dwc3-haps can claim it instead of xhci (Thinh Nguyen) - Clean up P2PDMA documentation (Randy Dunlap) - Allow runtime PM even if driver doesn't supply callbacks (Jarkko Nikula) - Remove status check after submitting Switchtec MRPC Firmware Download commands to avoid Completion Timeouts (Kelvin Cao) - Set Switchtec coherent DMA mask to allow 64-bit DMA (Boris Glimcher) - Fix Switchtec SWITCHTEC_IOCTL_EVENT_IDX_ALL flag overwrite issue (Joey Zhang) - Enable write combining for Switchtec MRPC Input buffers (Kelvin Cao) - Add Switchtec MRPC DMA mode support (Wesley Sheng) - Skip VF scanning on powerpc, which does this in firmware (Sebastian Ott) - Add Amlogic Meson PCIe controller driver and DT bindings (Yue Wang) - Constify histb dw_pcie_host_ops structure (Julia Lawall) - Support multiple power domains for imx6 (Leonard Crestez) - Constify layerscape driver data (Stefan Agner) - Update imx6 Kconfig to allow imx6 PCIe in imx7 kernel (Trent Piepho) - Support armada8k GPIO reset (Baruch Siach) - Support suspend/resume support on imx6 (Leonard Crestez) - Don't hard-code DesignWare DBI/ATU offst (Stephen Warren) - Skip i.MX6 PHY setup on i.MX7D (Andrey Smirnov) - Remove Jianguo Sun from HiSilicon STB maintainers (Lorenzo Pieralisi) - Mask DesignWare interrupts instead of disabling them to avoid lost interrupts (Marc Zyngier) - Add locking when acking DesignWare interrupts (Marc Zyngier) - Ack DesignWare interrupts in the proper callbacks (Marc Zyngier) - Use devm resource parser in mediatek (Honghui Zhang) - Remove unused mediatek "num-lanes" DT property (Honghui Zhang) - Add UniPhier PCIe controller driver and DT bindings (Kunihiko Hayashi) - Enable MSI for imx6 downstream components (Richard Zhu) * tag 'pci-v4.21-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (40 commits) PCI: imx: Enable MSI from downstream components s390/pci: skip VF scanning PCI/IOV: Add flag so platforms can skip VF scanning PCI/IOV: Factor out sriov_add_vfs() PCI: uniphier: Add UniPhier PCIe host controller support dt-bindings: PCI: Add UniPhier PCIe host controller description PCI: amlogic: Add the Amlogic Meson PCIe controller driver dt-bindings: PCI: meson: add DT bindings for Amlogic Meson PCIe controller arm64: dts: mt7622: Remove un-used property for PCIe arm: dts: mt7623: Remove un-used property for PCIe dt-bindings: PCI: MediaTek: Remove un-used property PCI: mediatek: Remove un-used variant in struct mtk_pcie_port MAINTAINERS: Remove Jianguo Sun from HiSilicon STB DWC entry PCI: dwc: Don't hard-code DBI/ATU offset PCI: imx: Add imx6sx suspend/resume support PCI: armada8k: Add support for gpio controlled reset signal PCI: dwc: Adjust Kconfig to allow IMX6 PCIe host on IMX7 PCI: dwc: layerscape: Constify driver data PCI: imx: Add multi-pd support PCI: Override Synopsys USB 3.x HAPS device class ...
2018-12-28mm, hmm: mark hmm_devmem_{add, add_resource} EXPORT_SYMBOL_GPLDan Williams
At Maintainer Summit, Greg brought up a topic I proposed around EXPORT_SYMBOL_GPL usage. The motivation was considerations for when EXPORT_SYMBOL_GPL is warranted and the criteria for taking the exceptional step of reclassifying an existing export. Specifically, I wanted to make the case that although the line is fuzzy and hard to specify in abstract terms, it is nonetheless clear that devm_memremap_pages() and HMM (Heterogeneous Memory Management) have crossed it. The devm_memremap_pages() facility should have been EXPORT_SYMBOL_GPL from the beginning, and HMM as a derivative of that functionality should have naturally picked up that designation as well. Contrary to typical rules, the HMM infrastructure was merged upstream with zero in-tree consumers. There was a promise at the time that those users would be merged "soon", but it has been over a year with no drivers arriving. While the Nouveau driver is about to belatedly make good on that promise it is clear that HMM was targeted first and foremost at an out-of-tree consumer. HMM is derived from devm_memremap_pages(), a facility Christoph and I spearheaded to support persistent memory. It combines a device lifetime model with a dynamically created 'struct page' / memmap array for any physical address range. It enables coordination and control of the many code paths in the kernel built to interact with memory via 'struct page' objects. With HMM the integration goes even deeper by allowing device drivers to hook and manipulate page fault and page free events. One interpretation of when EXPORT_SYMBOL is suitable is when it is exporting stable and generic leaf functionality. The devm_memremap_pages() facility continues to see expanding use cases, peer-to-peer DMA being the most recent, with no clear end date when it will stop attracting reworks and semantic changes. It is not suitable to export devm_memremap_pages() as a stable 3rd party driver API due to the fact that it is still changing and manipulates core behavior. Moreover, it is not in the best interest of the long term development of the core memory management subsystem to permit any external driver to effectively define its own system-wide memory management policies with no encouragement to engage with upstream. I am also concerned that HMM was designed in a way to minimize further engagement with the core-MM. That, with these hooks in place, device-drivers are free to implement their own policies without much consideration for whether and how the core-MM could grow to meet that need. Going forward not only should HMM be EXPORT_SYMBOL_GPL, but the core-MM should be allowed the opportunity and stimulus to change and address these new use cases as first class functionality. Original changelog: hmm_devmem_add(), and hmm_devmem_add_resource() duplicated devm_memremap_pages() and are now simple now wrappers around the core facility to inject a dev_pagemap instance into the global pgmap_radix and hook page-idle events. The devm_memremap_pages() interface is base infrastructure for HMM. HMM has more and deeper ties into the kernel memory management implementation than base ZONE_DEVICE which is itself a EXPORT_SYMBOL_GPL facility. Originally, the HMM page structure creation routines copied the devm_memremap_pages() code and reused ZONE_DEVICE. A cleanup to unify the implementations was discussed during the initial review: http://lkml.iu.edu/hypermail/linux/kernel/1701.2/00812.html Recent work to extend devm_memremap_pages() for the peer-to-peer-DMA facility enabled this cleanup to move forward. In addition to the integration with devm_memremap_pages() HMM depends on other GPL-only symbols: mmu_notifier_unregister_no_release percpu_ref region_intersects __class_create It goes further to consume / indirectly expose functionality that is not exported to any other driver: alloc_pages_vma walk_page_range HMM is derived from devm_memremap_pages(), and extends deep core-kernel fundamentals. Similar to devm_memremap_pages(), mark its entry points EXPORT_SYMBOL_GPL(). [logang@deltatee.com: PCI/P2PDMA: match interface changes to devm_memremap_pages()] Link: http://lkml.kernel.org/r/20181130225911.2900-1-logang@deltatee.com Link: http://lkml.kernel.org/r/154275560565.76910.15919297436557795278.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Logan Gunthorpe <logang@deltatee.com> Cc: "Jérôme Glisse" <jglisse@redhat.com> Cc: Balbir Singh <bsingharora@gmail.com>, Cc: Michal Hocko <mhocko@suse.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-11PCI/P2PDMA: Clean up documentation and kernel-docRandy Dunlap
Fix typos, spellos, and grammar in p2pdma.rst and p2pdma.c. Fix return value(s) in function pci_p2pmem_alloc_sgl(). Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Logan Gunthorpe <logang@deltatee.com> Cc: Jonathan Corbet <corbet@lwn.net>
2018-10-17PCI/P2PDMA: Introduce configfs/sysfs enable attribute helpersLogan Gunthorpe
Users of the P2PDMA infrastructure will typically need a way for the user to tell the kernel to use P2P resources. Typically this will be a simple on/off boolean operation but sometimes it may be desirable for the user to specify the exact device to use for the P2P operation. Add new helpers for attributes which take a boolean or a PCI device. Any boolean as accepted by strtobool() turn P2P on or off (such as 'y', 'n', '1', '0', etc). Specifying a full PCI device name/BDF will select the specific device. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2018-10-17PCI/P2PDMA: Add PCI p2pmem DMA mappings to adjust the bus offsetLogan Gunthorpe
The DMA address used when mapping PCI P2P memory must be the PCI bus address. Thus, introduce pci_p2pmem_map_sg() to map the correct addresses when using P2P memory. Memory mapped in this way does not need to be unmapped and thus if we provided pci_p2pmem_unmap_sg() it would be empty. This breaks the expected balance between map/unmap but was left out as an empty function doesn't really provide any benefit. In the future, if this call becomes necessary it can be added without much difficulty. For this, we assume that an SGL passed to these functions contain all P2P memory or no P2P memory. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2018-10-17PCI/P2PDMA: Add sysfs group to display p2pmem statsLogan Gunthorpe
Add a sysfs group to display statistics about P2P memory that is registered in each PCI device. Attributes in the group display the total amount of P2P memory, the amount available and whether it is published or not. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2018-10-10PCI/P2PDMA: Support peer-to-peer memoryLogan Gunthorpe
Some PCI devices may have memory mapped in a BAR space that's intended for use in peer-to-peer transactions. To enable such transactions the memory must be registered with ZONE_DEVICE pages so it can be used by DMA interfaces in existing drivers. Add an interface for other subsystems to find and allocate chunks of P2P memory as necessary to facilitate transfers between two PCI peers: struct pci_dev *pci_p2pmem_find[_many](); int pci_p2pdma_distance[_many](); void *pci_alloc_p2pmem(); The new interface requires a driver to collect a list of client devices involved in the transaction then call pci_p2pmem_find() to obtain any suitable P2P memory. Alternatively, if the caller knows a device which provides P2P memory, they can use pci_p2pdma_distance() to determine if it is usable. With a suitable p2pmem device, memory can then be allocated with pci_alloc_p2pmem() for use in DMA transactions. Depending on hardware, using peer-to-peer memory may reduce the bandwidth of the transfer but can significantly reduce pressure on system memory. This may be desirable in many cases: for example a system could be designed with a small CPU connected to a PCIe switch by a small number of lanes which would maximize the number of lanes available to connect to NVMe devices. The code is designed to only utilize the p2pmem device if all the devices involved in a transfer are behind the same PCI bridge. This is because we have no way of knowing whether peer-to-peer routing between PCIe Root Ports is supported (PCIe r4.0, sec 1.3.1). Additionally, the benefits of P2P transfers that go through the RC is limited to only reducing DRAM usage and, in some cases, coding convenience. The PCI-SIG may be exploring adding a new capability bit to advertise whether this is possible for future hardware. This commit includes significant rework and feedback from Christoph Hellwig. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Logan Gunthorpe <logang@deltatee.com> [bhelgaas: fold in fix from Keith Busch <keith.busch@intel.com>: https://lore.kernel.org/linux-pci/20181012155920.15418-1-keith.busch@intel.com, to address comment from Dan Carpenter <dan.carpenter@oracle.com>, fold in https://lore.kernel.org/linux-pci/20181017160510.17926-1-logang@deltatee.com] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>