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2019-05-13Merge tag 'iommu-updates-v5.2' of ↵Linus Torvalds
ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/joro/iommu Pull IOMMU updates from Joerg Roedel: - ATS support for ARM-SMMU-v3. - AUX domain support in the IOMMU-API and the Intel VT-d driver. This adds support for multiple DMA address spaces per (PCI-)device. The use-case is to multiplex devices between host and KVM guests in a more flexible way than supported by SR-IOV. - the rest are smaller cleanups and fixes, two of which needed to be reverted after testing in linux-next. * tag 'iommu-updates-v5.2' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (45 commits) Revert "iommu/amd: Flush not present cache in iommu_map_page" Revert "iommu/amd: Remove the leftover of bypass support" iommu/vt-d: Fix leak in intel_pasid_alloc_table on error path iommu/vt-d: Make kernel parameter igfx_off work with vIOMMU iommu/vt-d: Set intel_iommu_gfx_mapped correctly iommu/amd: Flush not present cache in iommu_map_page iommu/vt-d: Cleanup: no spaces at the start of a line iommu/vt-d: Don't request page request irq under dmar_global_lock iommu/vt-d: Use struct_size() helper iommu/mediatek: Fix leaked of_node references iommu/amd: Remove amd_iommu_pd_list iommu/arm-smmu: Log CBFRSYNRA register on context fault iommu/arm-smmu-v3: Don't disable SMMU in kdump kernel iommu/arm-smmu-v3: Disable tagged pointers iommu/arm-smmu-v3: Add support for PCI ATS iommu/arm-smmu-v3: Link domains and devices iommu/arm-smmu-v3: Add a master->domain pointer iommu/arm-smmu-v3: Store SteamIDs in master iommu/arm-smmu-v3: Rename arm_smmu_master_data to arm_smmu_master ACPI/IORT: Check ATS capability in root complex nodes ...
2019-05-07vfio/mdev: Avoid inline get and put parent helpersParav Pandit
As section 15 of Documentation/process/coding-style.rst clearly describes that compiler will be able to optimize code. Hence drop inline for get and put helpers for parent. Signed-off-by: Parav Pandit <parav@mellanox.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2019-05-07vfio/mdev: Fix aborting mdev child device removal if one failsParav Pandit
device_for_each_child() stops executing callback function for remaining child devices, if callback hits an error. Each child mdev device is independent of each other. While unregistering parent device, mdev core must remove all child mdev devices. Therefore, mdev_device_remove_cb() always returns success so that device_for_each_child doesn't abort if one child removal hits error. While at it, improve remove and unregister functions for below simplicity. There isn't need to pass forced flag pointer during mdev parent removal which invokes mdev_device_remove(). So simplify the flow. mdev_device_remove() is called from two paths. 1. mdev_unregister_driver() mdev_device_remove_cb() mdev_device_remove() 2. remove_store() mdev_device_remove() Fixes: 7b96953bc640 ("vfio: Mediated device Core driver") Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Parav Pandit <parav@mellanox.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2019-05-07vfio/mdev: Follow correct remove sequenceParav Pandit
mdev_remove_sysfs_files() should follow exact mirror sequence of a create, similar to what is followed in error unwinding path of mdev_create_sysfs_files(). Fixes: 6a62c1dfb5c7 ("vfio/mdev: Re-order sysfs attribute creation") Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Parav Pandit <parav@mellanox.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2019-05-07vfio/mdev: Avoid masking error code to EBUSYParav Pandit
Instead of masking return error to -EBUSY, return actual error returned by the driver. Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Parav Pandit <parav@mellanox.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2019-05-07vfio/mdev: Removed unused krefParav Pandit
Remove unused kref from the mdev_device structure. Fixes: 7b96953bc640 ("vfio: Mediated device Core driver") Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Parav Pandit <parav@mellanox.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2019-05-07vfio/mdev: Avoid release parent reference during error pathParav Pandit
During mdev parent registration in mdev_register_device(), if parent device is duplicate, it releases the reference of existing parent device. This is incorrect. Existing parent device should not be touched. Fixes: 7b96953bc640 ("vfio: Mediated device Core driver") Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Parav Pandit <parav@mellanox.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2019-04-12vfio/mdev: Add iommu related member in mdev_deviceLu Baolu
A parent device might create different types of mediated devices. For example, a mediated device could be created by the parent device with full isolation and protection provided by the IOMMU. One usage case could be found on Intel platforms where a mediated device is an assignable subset of a PCI, the DMA requests on behalf of it are all tagged with a PASID. Since IOMMU supports PASID-granular translations (scalable mode in VT-d 3.0), this mediated device could be individually protected and isolated by an IOMMU. This patch adds a new member in the struct mdev_device to indicate that the mediated device represented by mdev could be isolated and protected by attaching a domain to a device represented by mdev->iommu_device. It also adds a helper to add or set the iommu device. * mdev_device->iommu_device - This, if set, indicates that the mediated device could be fully isolated and protected by IOMMU via attaching an iommu domain to this device. If empty, it indicates using vendor defined isolation, hence bypass IOMMU. * mdev_set/get_iommu_device(dev, iommu_device) - Set or get the iommu device which represents this mdev in IOMMU's device scope. Drivers don't need to set the iommu device if it uses vendor defined isolation. Cc: Ashok Raj <ashok.raj@intel.com> Cc: Jacob Pan <jacob.jun.pan@linux.intel.com> Cc: Kevin Tian <kevin.tian@intel.com> Cc: Liu Yi L <yi.l.liu@intel.com> Suggested-by: Kevin Tian <kevin.tian@intel.com> Suggested-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Reviewed-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com> Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com> Acked-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-02-05vfio-mdev: Switch to use new generic UUID APIAndy Shevchenko
There are new types and helpers that are supposed to be used in new code. As a preparation to get rid of legacy types and API functions do the conversion here. Cc: Kirti Wankhede <kwankhede@nvidia.com> Cc: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-12-12vfio/mdev: add static modifier to add_mdev_supported_typePaolo Cretaro
Set add_mdev_supported_type as static since it is only used within mdev_sysfs.c. This fixes -Wmissing-prototypes gcc warning. Signed-off-by: Paolo Cretaro <paolocretaro@gmail.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-06-08vfio/mdev: Re-order sysfs attribute creationAlex Williamson
There exists a gap at the end of mdev_device_create() where the device is visible to userspace, but we're not yet ready to handle removal, as triggered through the 'remove' attribute. We handle this properly in mdev_device_remove() with an -EAGAIN return, but we can marginally reduce this gap by adding this attribute as a final step of our sysfs setup. Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Acked-by: Halil Pasic <pasic@linux.ibm.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-06-08vfio/mdev: Check globally for duplicate devicesAlex Williamson
When we create an mdev device, we check for duplicates against the parent device and return -EEXIST if found, but the mdev device namespace is global since we'll link all devices from the bus. We do catch this later in sysfs_do_create_link_sd() to return -EEXIST, but with it comes a kernel warning and stack trace for trying to create duplicate sysfs links, which makes it an undesirable response. Therefore we should really be looking for duplicates across all mdev parent devices, or as implemented here, against our mdev device list. Using mdev_list to prevent duplicates means that we can remove mdev_parent.lock, but in order not to serialize mdev device creation and removal globally, we add mdev_device.active which allows UUIDs to be reserved such that we can drop the mdev_list_lock before the mdev device is fully in place. Two behavioral notes; first, mdev_parent.lock had the side-effect of serializing mdev create and remove ops per parent device. This was an implementation detail, not an intentional guarantee provided to the mdev vendor drivers. Vendor drivers can trivially provide this serialization internally if necessary. Second, review comments note the new -EAGAIN behavior when the device, and in particular the remove attribute, becomes visible in sysfs. If a remove is triggered prior to completion of mdev_device_create() the user will see a -EAGAIN error. While the errno is different, receiving an error during this period is not, the previous implementation returned -ENODEV for the same condition. Furthermore, the consistency to the user is improved in the case where mdev_device_remove_ops() returns error. Previously concurrent calls to mdev_device_remove() could see the device disappear with -ENODEV and return in the case of error. Now a user would see -EAGAIN while the device is in this transitory state. Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Acked-by: Halil Pasic <pasic@linux.ibm.com> Acked-by: Zhenyu Wang <zhenyuw@linux.intel.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-01-09vfio: mdev: make a couple of functions and structure vfio_mdev_driver staticXiongwei Song
The functions vfio_mdev_probe, vfio_mdev_remove and the structure vfio_mdev_driver are only used in this file, so make them static. Clean up sparse warnings: drivers/vfio/mdev/vfio_mdev.c:114:5: warning: no previous prototype for 'vfio_mdev_probe' [-Wmissing-prototypes] drivers/vfio/mdev/vfio_mdev.c:121:6: warning: no previous prototype for 'vfio_mdev_remove' [-Wmissing-prototypes] Signed-off-by: Xiongwei Song <sxwjean@gmail.com> Reviewed-by: Quan Xu <quan.xu0@gmail.com> Reviewed-by: Liu, Yi L <yi.l.liu@intel.com> Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2017-02-08vfio/mdev: Use a module softdep for vfio_mdevAlex Williamson
Use an explicit module softdep rather than a request module call such that the dependency is exposed to userspace. This allows us to more easily support modules loaded at initrd time. Reviewed by: Kirti Wankhede <kwankhede@nvidia.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-12-30vfio-mdev: Make mdev_device private and abstract interfacesAlex Williamson
Abstract access to mdev_device so that we can define which interfaces are public rather than relying on comments in the structure. Cc: Zhenyu Wang <zhenyuw@linux.intel.com> Cc: Zhi Wang <zhi.a.wang@intel.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Reviewed-by: Jike Song <jike.song@intel.com> Reviewed by: Kirti Wankhede <kwankhede@nvidia.com>
2016-12-30vfio-mdev: Make mdev_parent privateAlex Williamson
Rather than hoping for good behavior by marking some elements internal, enforce it by making the entire structure private and creating an accessor function for the one useful external field. Cc: Zhenyu Wang <zhenyuw@linux.intel.com> Cc: Zhi Wang <zhi.a.wang@intel.com> Cc: Jike Song <jike.song@intel.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Reviewed by: Kirti Wankhede <kwankhede@nvidia.com>
2016-12-30vfio-mdev: de-polute the namespace, rename parent_device & parent_opsAlex Williamson
Add an mdev_ prefix so we're not poluting the namespace so much. Cc: Zhenyu Wang <zhenyuw@linux.intel.com> Cc: Zhi Wang <zhi.a.wang@intel.com> Cc: Jike Song <jike.song@intel.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Reviewed by: Kirti Wankhede <kwankhede@nvidia.com>
2016-12-30vfio-mdev: Fix remove raceAlex Williamson
Using the mtty mdev sample driver we can generate a remove race by starting one shell that continuously creates mtty devices and several other shells all attempting to remove devices, in my case four remove shells. The fault occurs in mdev_remove_sysfs_files() where the passed type arg is NULL, which suggests we've received a struct device in mdev_device_remove() but it's in some sort of teardown state. The solution here is to make use of the accidentally unused list_head on the mdev_device such that the mdev core keeps a list of all the mdev devices. This allows us to validate that we have a valid mdev before we start removal, remove it from the list to prevent others from working on it, and if the vendor driver refuses to remove, we can re-add it to the list. Cc: Kirti Wankhede <kwankhede@nvidia.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-11-17docs: Add Documentation for Mediated devicesKirti Wankhede
Add file Documentation/vfio-mediated-device.txt that include details of mediated device framework. Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com> Signed-off-by: Neo Jia <cjia@nvidia.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-11-17vfio: VFIO based driver for Mediated devicesKirti Wankhede
vfio_mdev driver registers with mdev core driver. mdev core driver creates mediated device and calls probe routine of vfio_mdev driver for each device. Probe routine of vfio_mdev driver adds mediated device to VFIO core module This driver forms a shim layer that pass through VFIO devices operations to vendor driver for mediated devices. Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com> Signed-off-by: Neo Jia <cjia@nvidia.com> Reviewed-by: Jike Song <jike.song@intel.com> Reviewed-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-11-17vfio: Mediated device Core driverKirti Wankhede
Design for Mediated Device Driver: Main purpose of this driver is to provide a common interface for mediated device management that can be used by different drivers of different devices. This module provides a generic interface to create the device, add it to mediated bus, add device to IOMMU group and then add it to vfio group. Below is the high Level block diagram, with Nvidia, Intel and IBM devices as example, since these are the devices which are going to actively use this module as of now. +---------------+ | | | +-----------+ | mdev_register_driver() +--------------+ | | | +<------------------------+ __init() | | | mdev | | | | | | bus | +------------------------>+ |<-> VFIO user | | driver | | probe()/remove() | vfio_mdev.ko | APIs | | | | | | | +-----------+ | +--------------+ | | | MDEV CORE | | MODULE | | mdev.ko | | +-----------+ | mdev_register_device() +--------------+ | | | +<------------------------+ | | | | | | nvidia.ko |<-> physical | | | +------------------------>+ | device | | | | callback +--------------+ | | Physical | | | | device | | mdev_register_device() +--------------+ | | interface | |<------------------------+ | | | | | | i915.ko |<-> physical | | | +------------------------>+ | device | | | | callback +--------------+ | | | | | | | | mdev_register_device() +--------------+ | | | +<------------------------+ | | | | | | ccw_device.ko|<-> physical | | | +------------------------>+ | device | | | | callback +--------------+ | +-----------+ | +---------------+ Core driver provides two types of registration interfaces: 1. Registration interface for mediated bus driver: /** * struct mdev_driver - Mediated device's driver * @name: driver name * @probe: called when new device created * @remove:called when device removed * @driver:device driver structure * **/ struct mdev_driver { const char *name; int (*probe) (struct device *dev); void (*remove) (struct device *dev); struct device_driver driver; }; Mediated bus driver for mdev device should use this interface to register and unregister with core driver respectively: int mdev_register_driver(struct mdev_driver *drv, struct module *owner); void mdev_unregister_driver(struct mdev_driver *drv); Mediated bus driver is responsible to add/delete mediated devices to/from VFIO group when devices are bound and unbound to the driver. 2. Physical device driver interface This interface provides vendor driver the set APIs to manage physical device related work in its driver. APIs are : * dev_attr_groups: attributes of the parent device. * mdev_attr_groups: attributes of the mediated device. * supported_type_groups: attributes to define supported type. This is mandatory field. * create: to allocate basic resources in vendor driver for a mediated device. This is mandatory to be provided by vendor driver. * remove: to free resources in vendor driver when mediated device is destroyed. This is mandatory to be provided by vendor driver. * open: open callback of mediated device * release: release callback of mediated device * read : read emulation callback. * write: write emulation callback. * ioctl: ioctl callback. * mmap: mmap emulation callback. Drivers should use these interfaces to register and unregister device to mdev core driver respectively: extern int mdev_register_device(struct device *dev, const struct parent_ops *ops); extern void mdev_unregister_device(struct device *dev); There are no locks to serialize above callbacks in mdev driver and vfio_mdev driver. If required, vendor driver can have locks to serialize above APIs in their driver. Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com> Signed-off-by: Neo Jia <cjia@nvidia.com> Reviewed-by: Jike Song <jike.song@intel.com> Reviewed-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>