kernel/linux.git/drivers/iommu/Kconfig, branch v6.2

Merge tag 'for-linus-iommufd' of git://git.kernel.org/pub/scm/linux/kernel/git/jgg/iommufd

2022-12-14T17:15:43+00:00

Pull iommufd implementation from Jason Gunthorpe: "iommufd is the user API to control the IOMMU subsystem as it relates to managing IO page tables that point at user space memory. It takes over from drivers/vfio/vfio_iommu_type1.c (aka the VFIO container) which is the VFIO specific interface for a similar idea. We see a broad need for extended features, some being highly IOMMU device specific: - Binding iommu_domain's to PASID/SSID - Userspace IO page tables, for ARM, x86 and S390 - Kernel bypassed invalidation of user page tables - Re-use of the KVM page table in the IOMMU - Dirty page tracking in the IOMMU - Runtime Increase/Decrease of IOPTE size - PRI support with faults resolved in userspace Many of these HW features exist to support VM use cases - for instance the combination of PASID, PRI and Userspace IO Page Tables allows an implementation of DMA Shared Virtual Addressing (vSVA) within a guest. Dirty tracking enables VM live migration with SRIOV devices and PASID support allow creating "scalable IOV" devices, among other things. As these features are fundamental to a VM platform they need to be uniformly exposed to all the driver families that do DMA into VMs, which is currently VFIO and VDPA" For more background, see the extended explanations in Jason's pull request: https://lore.kernel.org/lkml/Y5dzTU8dlmXTbzoJ@nvidia.com/ * tag 'for-linus-iommufd' of git://git.kernel.org/pub/scm/linux/kernel/git/jgg/iommufd: (62 commits) iommufd: Change the order of MSI setup iommufd: Improve a few unclear bits of code iommufd: Fix comment typos vfio: Move vfio group specific code into group.c vfio: Refactor dma APIs for emulated devices vfio: Wrap vfio group module init/clean code into helpers vfio: Refactor vfio_device open and close vfio: Make vfio_device_open() truly device specific vfio: Swap order of vfio_device_container_register() and open_device() vfio: Set device->group in helper function vfio: Create wrappers for group register/unregister vfio: Move the sanity check of the group to vfio_create_group() vfio: Simplify vfio_create_group() iommufd: Allow iommufd to supply /dev/vfio/vfio vfio: Make vfio_container optionally compiled vfio: Move container related MODULE_ALIAS statements into container.c vfio-iommufd: Support iommufd for emulated VFIO devices vfio-iommufd: Support iommufd for physical VFIO devices vfio-iommufd: Allow iommufd to be used in place of a container fd vfio: Use IOMMU_CAP_ENFORCE_CACHE_COHERENCY for vfio_file_enforced_coherent() ...

Merge tag 'irq-core-2022-12-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2022-12-12T19:21:29+00:00

Pull irq updates from Thomas Gleixner: "Updates for the interrupt core and driver subsystem: The bulk is the rework of the MSI subsystem to support per device MSI interrupt domains. This solves conceptual problems of the current PCI/MSI design which are in the way of providing support for PCI/MSI[-X] and the upcoming PCI/IMS mechanism on the same device. IMS (Interrupt Message Store] is a new specification which allows device manufactures to provide implementation defined storage for MSI messages (as opposed to PCI/MSI and PCI/MSI-X that has a specified message store which is uniform accross all devices). The PCI/MSI[-X] uniformity allowed us to get away with "global" PCI/MSI domains. IMS not only allows to overcome the size limitations of the MSI-X table, but also gives the device manufacturer the freedom to store the message in arbitrary places, even in host memory which is shared with the device. There have been several attempts to glue this into the current MSI code, but after lengthy discussions it turned out that there is a fundamental design problem in the current PCI/MSI-X implementation. This needs some historical background. When PCI/MSI[-X] support was added around 2003, interrupt management was completely different from what we have today in the actively developed architectures. Interrupt management was completely architecture specific and while there were attempts to create common infrastructure the commonalities were rudimentary and just providing shared data structures and interfaces so that drivers could be written in an architecture agnostic way. The initial PCI/MSI[-X] support obviously plugged into this model which resulted in some basic shared infrastructure in the PCI core code for setting up MSI descriptors, which are a pure software construct for holding data relevant for a particular MSI interrupt, but the actual association to Linux interrupts was completely architecture specific. This model is still supported today to keep museum architectures and notorious stragglers alive. In 2013 Intel tried to add support for hot-pluggable IO/APICs to the kernel, which was creating yet another architecture specific mechanism and resulted in an unholy mess on top of the existing horrors of x86 interrupt handling. The x86 interrupt management code was already an incomprehensible maze of indirections between the CPU vector management, interrupt remapping and the actual IO/APIC and PCI/MSI[-X] implementation. At roughly the same time ARM struggled with the ever growing SoC specific extensions which were glued on top of the architected GIC interrupt controller. This resulted in a fundamental redesign of interrupt management and provided the today prevailing concept of hierarchical interrupt domains. This allowed to disentangle the interactions between x86 vector domain and interrupt remapping and also allowed ARM to handle the zoo of SoC specific interrupt components in a sane way. The concept of hierarchical interrupt domains aims to encapsulate the functionality of particular IP blocks which are involved in interrupt delivery so that they become extensible and pluggable. The X86 encapsulation looks like this: |--- device 1 [Vector]---[Remapping]---[PCI/MSI]--|... |--- device N where the remapping domain is an optional component and in case that it is not available the PCI/MSI[-X] domains have the vector domain as their parent. This reduced the required interaction between the domains pretty much to the initialization phase where it is obviously required to establish the proper parent relation ship in the components of the hierarchy. While in most cases the model is strictly representing the chain of IP blocks and abstracting them so they can be plugged together to form a hierarchy, the design stopped short on PCI/MSI[-X]. Looking at the hardware it's clear that the actual PCI/MSI[-X] interrupt controller is not a global entity, but strict a per PCI device entity. Here we took a short cut on the hierarchical model and went for the easy solution of providing "global" PCI/MSI domains which was possible because the PCI/MSI[-X] handling is uniform across the devices. This also allowed to keep the existing PCI/MSI[-X] infrastructure mostly unchanged which in turn made it simple to keep the existing architecture specific management alive. A similar problem was created in the ARM world with support for IP block specific message storage. Instead of going all the way to stack a IP block specific domain on top of the generic MSI domain this ended in a construct which provides a "global" platform MSI domain which allows overriding the irq_write_msi_msg() callback per allocation. In course of the lengthy discussions we identified other abuse of the MSI infrastructure in wireless drivers, NTB etc. where support for implementation specific message storage was just mindlessly glued into the existing infrastructure. Some of this just works by chance on particular platforms but will fail in hard to diagnose ways when the driver is used on platforms where the underlying MSI interrupt management code does not expect the creative abuse. Another shortcoming of today's PCI/MSI-X support is the inability to allocate or free individual vectors after the initial enablement of MSI-X. This results in an works by chance implementation of VFIO (PCI pass-through) where interrupts on the host side are not set up upfront to avoid resource exhaustion. They are expanded at run-time when the guest actually tries to use them. The way how this is implemented is that the host disables MSI-X and then re-enables it with a larger number of vectors again. That works by chance because most device drivers set up all interrupts before the device actually will utilize them. But that's not universally true because some drivers allocate a large enough number of vectors but do not utilize them until it's actually required, e.g. for acceleration support. But at that point other interrupts of the device might be in active use and the MSI-X disable/enable dance can just result in losing interrupts and therefore hard to diagnose subtle problems. Last but not least the "global" PCI/MSI-X domain approach prevents to utilize PCI/MSI[-X] and PCI/IMS on the same device due to the fact that IMS is not longer providing a uniform storage and configuration model. The solution to this is to implement the missing step and switch from global PCI/MSI domains to per device PCI/MSI domains. The resulting hierarchy then looks like this: |--- [PCI/MSI] device 1 [Vector]---[Remapping]---|... |--- [PCI/MSI] device N which in turn allows to provide support for multiple domains per device: |--- [PCI/MSI] device 1 |--- [PCI/IMS] device 1 [Vector]---[Remapping]---|... |--- [PCI/MSI] device N |--- [PCI/IMS] device N This work converts the MSI and PCI/MSI core and the x86 interrupt domains to the new model, provides new interfaces for post-enable allocation/free of MSI-X interrupts and the base framework for PCI/IMS. PCI/IMS has been verified with the work in progress IDXD driver. There is work in progress to convert ARM over which will replace the platform MSI train-wreck. The cleanup of VFIO, NTB and other creative "solutions" are in the works as well. Drivers: - Updates for the LoongArch interrupt chip drivers - Support for MTK CIRQv2 - The usual small fixes and updates all over the place" * tag 'irq-core-2022-12-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (134 commits) irqchip/ti-sci-inta: Fix kernel doc irqchip/gic-v2m: Mark a few functions __init irqchip/gic-v2m: Include arm-gic-common.h irqchip/irq-mvebu-icu: Fix works by chance pointer assignment iommu/amd: Enable PCI/IMS iommu/vt-d: Enable PCI/IMS x86/apic/msi: Enable PCI/IMS PCI/MSI: Provide pci_ims_alloc/free_irq() PCI/MSI: Provide IMS (Interrupt Message Store) support genirq/msi: Provide constants for PCI/IMS support x86/apic/msi: Enable MSI_FLAG_PCI_MSIX_ALLOC_DYN PCI/MSI: Provide post-enable dynamic allocation interfaces for MSI-X PCI/MSI: Provide prepare_desc() MSI domain op PCI/MSI: Split MSI-X descriptor setup genirq/msi: Provide MSI_FLAG_MSIX_ALLOC_DYN genirq/msi: Provide msi_domain_alloc_irq_at() genirq/msi: Provide msi_domain_ops:: Prepare_desc() genirq/msi: Provide msi_desc:: Msi_data genirq/msi: Provide struct msi_map x86/apic/msi: Remove arch_create_remap_msi_irq_domain() ...

iommufd: File descriptor, context, kconfig and makefiles

2022-12-01T00:16:49+00:00

This is the basic infrastructure of a new miscdevice to hold the iommufd IOCTL API. It provides: - A miscdevice to create file descriptors to run the IOCTL interface over - A table based ioctl dispatch and centralized extendable pre-validation step - An xarray mapping userspace ID's to kernel objects. The design has multiple inter-related objects held within in a single IOMMUFD fd - A simple usage count to build a graph of object relations and protect against hostile userspace racing ioctls The only IOCTL provided in this patch is the generic 'destroy any object by handle' operation. Link: https://lore.kernel.org/r/6-v6-a196d26f289e+11787-iommufd_jgg@nvidia.com Reviewed-by: Lu Baolu Reviewed-by: Kevin Tian Reviewed-by: Eric Auger Tested-by: Nicolin Chen Tested-by: Yi Liu Tested-by: Lixiao Yang Tested-by: Matthew Rosato Signed-off-by: Yi Liu Signed-off-by: Jason Gunthorpe

iommu/hyper-v: Allow hyperv irq remapping without x2apic

2022-11-28T16:48:20+00:00

If x2apic is not available, hyperv-iommu skips remapping irqs. This breaks root partition which always needs irqs remapped. Fix this by allowing irq remapping regardless of x2apic, and change hyperv_enable_irq_remapping() to return IRQ_REMAP_XAPIC_MODE in case x2apic is missing. Tested with root and non-root hyperv partitions. Signed-off-by: Nuno Das Neves Reviewed-by: Tianyu Lan Reviewed-by: Michael Kelley Link: https://lore.kernel.org/r/1668715899-8971-1-git-send-email-nunodasneves@linux.microsoft.com Signed-off-by: Wei Liu

genirq: Get rid of GENERIC_MSI_IRQ_DOMAIN

2022-11-17T14:15:20+00:00

Adjust to reality and remove another layer of pointless Kconfig indirection. CONFIG_GENERIC_MSI_IRQ is good enough to serve all purposes. Signed-off-by: Thomas Gleixner Reviewed-by: Jason Gunthorpe Link: https://lore.kernel.org/r/20221111122014.524842979@linutronix.de

Merge branches 'apple/dart', 'arm/mediatek', 'arm/omap', 'arm/smmu', 'virtio', 'x86/vt-d', 'x86/amd' and 'core' into next

2022-09-26T13:52:31+00:00

iommu/io-pgtable: Move Apple DART support to its own file

2022-09-26T11:48:40+00:00

The pte format used by the DARTs found in the Apple M1 (t8103) is not fully compatible with io-pgtable-arm. The 24 MSB are used for subpage protection (mapping only parts of page) and conflict with the address mask. In addition bit 1 is not available for tagging entries but disables subpage protection. Subpage protection could be useful to support a CPU granule of 4k with the fixed IOMMU page size of 16k. The DARTs found on Apple M1 Pro/Max/Ultra use another different pte format which is even less compatible. To support an output address size of 42 bit the address is shifted down by 4. Subpage protection is mandatory and bit 1 signifies uncached mappings used by the display controller. It would be advantageous to share code for all known Apple DART variants to support common features. The page table allocator for DARTs is less complex since it uses a two levels of translation table without support for huge pages. Signed-off-by: Janne Grunau Acked-by: Robin Murphy Acked-by: Sven Peter Acked-by: Hector Martin Link: https://lore.kernel.org/r/20220916094152.87137-3-j@jannau.net [ joro: Fix compile warning in __dart_alloc_pages()] Signed-off-by: Joerg Roedel

iommu/dma: Clean up Kconfig

2022-09-07T12:46:59+00:00

Although iommu-dma is a per-architecture chonce, that is currently implemented in a rather haphazard way. Selecting from the arch Kconfig was the original logical approach, but is complicated by having to manage dependencies; conversely, selecting from drivers ends up hiding the architecture dependency *too* well. Instead, let's just have it enable itself automatically when IOMMU API support is enabled for the relevant architectures. It can't get much clearer than that. Signed-off-by: Robin Murphy Acked-by: Catalin Marinas Link: https://lore.kernel.org/r/2e33c8bc2b1bb478157b7964bfed976cb7466139.1660668998.git.robin.murphy@arm.com Signed-off-by: Joerg Roedel

Revert "iommu/dma: Add config for PCI SAC address trick"

2022-08-06T20:24:56+00:00

This reverts commit 4bf7fda4dce22214c70c49960b1b6438e6260b67. It turns out that it was hopelessly naive to think that this would work, considering that we've always done this. The first machine I actually tested this on broke at bootup, getting to Reached target cryptsetup.target - Local Encrypted Volumes. and then hanging. It's unclear what actually fails, since there's a lot else going on around that time (eg amdgpu probing also happens around that same time, but it could be some other random init thing that didn't complete earlier and just caused the boot to hang at that point). The expectations that we should default to some unsafe and untested mode seems entirely unfounded, and the belief that this wouldn't affect modern systems is clearly entirely false. The machine in question is about two years old, so it's not exactly shiny, but it's also not some dusty old museum piece PDP-11 in a closet. Cc: Robin Murphy Cc: Christoph Hellwig Cc: John Garry Cc: Joerg Roedel Signed-off-by: Linus Torvalds

Merge branches 'arm/exynos', 'arm/mediatek', 'arm/msm', 'arm/smmu', 'virtio', 'x86/vt-d', 'x86/amd' and 'core' into next

2022-07-29T10:06:56+00:00