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77943f4d |
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08-Feb-2024 |
Ricardo B. Marliere <ricardo@marliere.net> |
vfio: mdev: make mdev_bus_type const Now that the driver core can properly handle constant struct bus_type, move the mdev_bus_type variable to be a constant structure as well, placing it into read-only memory which can not be modified at runtime. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com> Link: https://lore.kernel.org/r/20240208-bus_cleanup-vfio-v1-1-ed5da3019949@marliere.net Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
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#
2815fe14 |
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23-Sep-2022 |
Christoph Hellwig <hch@lst.de> |
vfio/mdev: unexport mdev_bus_type mdev_bus_type is only used in mdev.ko now, so unexport it. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com> Link: https://lore.kernel.org/r/20220923092652.100656-8-hch@lst.de Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
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#
da44c340 |
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23-Sep-2022 |
Christoph Hellwig <hch@lst.de> |
vfio/mdev: simplify mdev_type handling Instead of abusing struct attribute_group to control initialization of struct mdev_type, just define the actual attributes in the mdev_driver, allocate the mdev_type structures in the caller and pass them to mdev_register_parent. This allows the caller to use container_of to get at the containing structure and thus significantly simplify the code. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com> Reviewed-by: Eric Farman <farman@linux.ibm.com> Link: https://lore.kernel.org/r/20220923092652.100656-6-hch@lst.de Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
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#
89345d51 |
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23-Sep-2022 |
Christoph Hellwig <hch@lst.de> |
vfio/mdev: embedd struct mdev_parent in the parent data structure Simplify mdev_{un}register_device by requiring the caller to pass in a structure allocate as part of the parent device structure. This removes the need for a list of parents and the separate mdev_parent refcount as we can simplify rely on the reference to the parent device. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com> Reviewed-by: Eric Farman <farman@linux.ibm.com> Link: https://lore.kernel.org/r/20220923092652.100656-5-hch@lst.de Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
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#
2aa72ec9 |
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11-Apr-2022 |
Jason Gunthorpe <jgg@ziepe.ca> |
vfio/mdev: Use the driver core to create the 'remove' file The device creator is supposed to use the dev.groups value to add sysfs files before device_add is called, not call sysfs_create_files() after device_add() returns. This creates a race with uevent delivery where the extra attribute will not be visible. This was being done because the groups had been co-opted by the mdev driver, now that prior patches have moved the driver's groups to the struct device_driver the dev.group is properly free for use here. Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Zhi Wang <zhi.a.wang@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/20220411141403.86980-34-hch@lst.de Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com> Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
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#
6b42f491 |
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11-Apr-2022 |
Jason Gunthorpe <jgg@ziepe.ca> |
vfio/mdev: Remove mdev_parent_ops The last useful member in this struct is the supported_type_groups, move it to the mdev_driver and delete mdev_parent_ops. Replace it with mdev_driver as an argument to mdev_register_device() Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Zhi Wang <zhi.a.wang@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/20220411141403.86980-33-hch@lst.de Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com> Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
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#
6c7f98b3 |
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11-Apr-2022 |
Jason Gunthorpe <jgg@ziepe.ca> |
vfio/mdev: Remove vfio_mdev.c Now that all mdev drivers directly create their own mdev_device driver and directly register with the vfio core's vfio_device_ops this is all dead code. Delete vfio_mdev.c and the mdev_parent_ops members that are connected to it. Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Zhi Wang <zhi.a.wang@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/20220411141403.86980-31-hch@lst.de Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com> Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
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#
af3ab3f9 |
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17-Jun-2021 |
Jason Gunthorpe <jgg@ziepe.ca> |
vfio/mdev: Remove CONFIG_VFIO_MDEV_DEVICE For some reason the vfio_mdev shim mdev_driver has its own module and kconfig. As the next patch requires access to it from mdev.ko merge the two modules together and remove VFIO_MDEV_DEVICE. A later patch deletes this driver entirely. Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com> Link: https://lore.kernel.org/r/20210617142218.1877096-7-hch@lst.de Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
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#
15fcc44b |
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06-Apr-2021 |
Jason Gunthorpe <jgg@ziepe.ca> |
vfio/mdev: Add mdev/mtype_get_type_group_id() This returns the index in the supported_type_groups array that is associated with the mdev_type attached to the struct mdev_device or its containing struct kobject. Each mdev_device can be spawned from exactly one mdev_type, which in turn originates from exactly one supported_type_group. Drivers are using weird string calculations to try and get back to this index, providing a direct access to the index removes a bunch of wonky driver code. mdev_type->group can be deleted as the group is obtained using the type_group_id. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Message-Id: <11-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
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#
a9f8111d |
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06-Apr-2021 |
Jason Gunthorpe <jgg@ziepe.ca> |
vfio/mdev: Expose mdev_get/put_parent to mdev_private.h The next patch will use these in mdev_sysfs.c While here remove the now dead code checks for NULL, a mdev_type can never have a NULL parent. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Message-Id: <6-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
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#
417fd5bf |
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06-Apr-2021 |
Jason Gunthorpe <jgg@ziepe.ca> |
vfio/mdev: Use struct mdev_type in struct mdev_device The kobj pointer in mdev_device is actually pointing at a struct mdev_type. Use the proper type so things are understandable. There are a number of places that are confused and passing both the mdev and the mtype as function arguments, fix these to derive the mtype directly from the mdev to remove the redundancy. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Message-Id: <5-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
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#
2a3d15f2 |
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06-Apr-2021 |
Jason Gunthorpe <jgg@ziepe.ca> |
vfio/mdev: Add missing typesafety around mdev_device The mdev API should accept and pass a 'struct mdev_device *' in all places, not pass a 'struct device *' and cast it internally with to_mdev_device(). Particularly in its struct mdev_driver functions, the whole point of a bus's struct device_driver wrapper is to provide type safety compared to the default struct device_driver. Further, the driver core standard is for bus drivers to expose their device structure in their public headers that can be used with container_of() inlines and '&foo->dev' to go between the class levels, and '&foo->dev' to be used with dev_err/etc driver core helper functions. Move 'struct mdev_device' to mdev.h Once done this allows moving some one instruction exported functions to static inlines, which in turns allows removing one of the two grotesque symbol_get()'s related to mdev in the core code. Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Message-Id: <3-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
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#
66873b5f |
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30-Mar-2021 |
Jason Gunthorpe <jgg@ziepe.ca> |
vfio/mdev: Make to_mdev_device() into a static inline The macro wrongly uses 'dev' as both the macro argument and the member name, which means it fails compilation if any caller uses a word other than 'dev' as the single argument. Fix this defect by making it into proper static inline, which is more clear and typesafe anyhow. Fixes: 99e3123e3d72 ("vfio-mdev: Make mdev_device private and abstract interfaces") Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Message-Id: <11-v3-225de1400dfc+4e074-vfio1_jgg@nvidia.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
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#
d0a7541d |
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30-Mar-2021 |
Zhen Lei <thunder.leizhen@huawei.com> |
vfio/mdev: Fix spelling mistake "interal" -> "internal" There is a spelling mistake in a comment, fix it. Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Message-Id: <20210326083528.1329-3-thunder.leizhen@huawei.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
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#
d2912cb1 |
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04-Jun-2019 |
Thomas Gleixner <tglx@linutronix.de> |
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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#
5715c4dd |
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06-Jun-2019 |
Parav Pandit <parav@mellanox.com> |
vfio/mdev: Synchronize device create/remove with parent removal In following sequences, child devices created while removing mdev parent device can be left out, or it may lead to race of removing half initialized child mdev devices. issue-1: -------- cpu-0 cpu-1 ----- ----- mdev_unregister_device() device_for_each_child() mdev_device_remove_cb() mdev_device_remove() create_store() mdev_device_create() [...] device_add() parent_remove_sysfs_files() /* BUG: device added by cpu-0 * whose parent is getting removed * and it won't process this mdev. */ issue-2: -------- Below crash is observed when user initiated remove is in progress and mdev_unregister_driver() completes parent unregistration. cpu-0 cpu-1 ----- ----- remove_store() mdev_device_remove() active = false; mdev_unregister_device() parent device removed. [...] parents->ops->remove() /* * BUG: Accessing invalid parent. */ This is similar race like create() racing with mdev_unregister_device(). BUG: unable to handle kernel paging request at ffffffffc0585668 PGD e8f618067 P4D e8f618067 PUD e8f61a067 PMD 85adca067 PTE 0 Oops: 0000 [#1] SMP PTI CPU: 41 PID: 37403 Comm: bash Kdump: loaded Not tainted 5.1.0-rc6-vdevbus+ #6 Hardware name: Supermicro SYS-6028U-TR4+/X10DRU-i+, BIOS 2.0b 08/09/2016 RIP: 0010:mdev_device_remove+0xfa/0x140 [mdev] Call Trace: remove_store+0x71/0x90 [mdev] kernfs_fop_write+0x113/0x1a0 vfs_write+0xad/0x1b0 ksys_write+0x5a/0xe0 do_syscall_64+0x5a/0x210 entry_SYSCALL_64_after_hwframe+0x49/0xbe Therefore, mdev core is improved as below to overcome above issues. Wait for any ongoing mdev create() and remove() to finish before unregistering parent device. This continues to allow multiple create and remove to progress in parallel for different mdev devices as most common case. At the same time guard parent removal while parent is being accessed by create() and remove() callbacks. create()/remove() and unregister_device() are synchronized by the rwsem. Refactor device removal code to mdev_device_remove_common() to avoid acquiring unreg_sem of the parent. Fixes: 7b96953bc640 ("vfio: Mediated device Core driver") Signed-off-by: Parav Pandit <parav@mellanox.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
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#
522ecce0 |
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06-Jun-2019 |
Parav Pandit <parav@mellanox.com> |
vfio/mdev: Improve the create/remove sequence This patch addresses below two issues and prepares the code to address 3rd issue listed below. 1. mdev device is placed on the mdev bus before it is created in the vendor driver. Once a device is placed on the mdev bus without creating its supporting underlying vendor device, mdev driver's probe() gets triggered. However there isn't a stable mdev available to work on. create_store() mdev_create_device() device_register() ... vfio_mdev_probe() [...] parent->ops->create() vfio_ap_mdev_create() mdev_set_drvdata(mdev, matrix_mdev); /* Valid pointer set above */ Due to this way of initialization, mdev driver who wants to use the mdev, doesn't have a valid mdev to work on. 2. Current creation sequence is, parent->ops_create() groups_register() Remove sequence is, parent->ops->remove() groups_unregister() However, remove sequence should be exact mirror of creation sequence. Once this is achieved, all users of the mdev will be terminated first before removing underlying vendor device. (Follow standard linux driver model). At that point vendor's remove() ops shouldn't fail because taking the device off the bus should terminate any usage. 3. When remove operation fails, mdev sysfs removal attempts to add the file back on already removed device. Following call trace [1] is observed. [1] call trace: kernel: WARNING: CPU: 2 PID: 9348 at fs/sysfs/file.c:327 sysfs_create_file_ns+0x7f/0x90 kernel: CPU: 2 PID: 9348 Comm: bash Kdump: loaded Not tainted 5.1.0-rc6-vdevbus+ #6 kernel: Hardware name: Supermicro SYS-6028U-TR4+/X10DRU-i+, BIOS 2.0b 08/09/2016 kernel: RIP: 0010:sysfs_create_file_ns+0x7f/0x90 kernel: Call Trace: kernel: remove_store+0xdc/0x100 [mdev] kernel: kernfs_fop_write+0x113/0x1a0 kernel: vfs_write+0xad/0x1b0 kernel: ksys_write+0x5a/0xe0 kernel: do_syscall_64+0x5a/0x210 kernel: entry_SYSCALL_64_after_hwframe+0x49/0xbe Therefore, mdev core is improved in following ways. 1. Split the device registration/deregistration sequence so that some things can be done between initialization of the device and hooking it up to the bus respectively after deregistering it from the bus but before giving up our final reference. In particular, this means invoking the ->create() and ->remove() callbacks in those new windows. This gives the vendor driver an initialized mdev device to work with during creation. At the same time, a bus driver who wish to bind to mdev driver also gets initialized mdev device. This follows standard Linux kernel bus and device model. 2. During remove flow, first remove the device from the bus. This ensures that any bus specific devices are removed. Once device is taken off the mdev bus, invoke remove() of mdev from the vendor driver. 3. The driver core device model provides way to register and auto unregister the device sysfs attribute groups at dev->groups. Make use of dev->groups to let core create the groups and eliminate code to avoid explicit groups creation and removal. To ensure, that new sequence is solid, a below stack dump of a process is taken who attempts to remove the device while device is in use by vfio driver and user application. This stack dump validates that vfio driver guards against such device removal when device is in use. cat /proc/21962/stack [<0>] vfio_del_group_dev+0x216/0x3c0 [vfio] [<0>] mdev_remove+0x21/0x40 [mdev] [<0>] device_release_driver_internal+0xe8/0x1b0 [<0>] bus_remove_device+0xf9/0x170 [<0>] device_del+0x168/0x350 [<0>] mdev_device_remove_common+0x1d/0x50 [mdev] [<0>] mdev_device_remove+0x8c/0xd0 [mdev] [<0>] remove_store+0x71/0x90 [mdev] [<0>] kernfs_fop_write+0x113/0x1a0 [<0>] vfs_write+0xad/0x1b0 [<0>] ksys_write+0x5a/0xe0 [<0>] do_syscall_64+0x5a/0x210 [<0>] entry_SYSCALL_64_after_hwframe+0x49/0xbe [<0>] 0xffffffffffffffff This prepares the code to eliminate calling device_create_file() in subsequent patch. Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Parav Pandit <parav@mellanox.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
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f707d837 |
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30-Apr-2019 |
Parav Pandit <parav@mellanox.com> |
vfio/mdev: Removed unused kref 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>
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#
8ac13175 |
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11-Apr-2019 |
Lu Baolu <baolu.lu@linux.intel.com> |
vfio/mdev: Add iommu related member in mdev_device 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>
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#
278bca7f |
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10-Jan-2019 |
Andy Shevchenko <andriy.shevchenko@linux.intel.com> |
vfio-mdev: Switch to use new generic UUID API 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>
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002fe996 |
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15-May-2018 |
Alex Williamson <alex.williamson@redhat.com> |
vfio/mdev: Check globally for duplicate devices 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>
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#
99e3123e |
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30-Dec-2016 |
Alex Williamson <alex.williamson@redhat.com> |
vfio-mdev: Make mdev_device private and abstract interfaces 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>
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#
9372e6fe |
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30-Dec-2016 |
Alex Williamson <alex.williamson@redhat.com> |
vfio-mdev: Make mdev_parent private 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>
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#
42930553 |
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30-Dec-2016 |
Alex Williamson <alex.williamson@redhat.com> |
vfio-mdev: de-polute the namespace, rename parent_device & parent_ops 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>
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7b96953b |
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16-Nov-2016 |
Kirti Wankhede <kwankhede@nvidia.com> |
vfio: Mediated device Core driver 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>
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