Commit graph

63 commits

Author SHA1 Message Date
Christoph Hellwig
c68ea0d00a vfio: simplify iommu group allocation for mediated devices
Reuse the logic in vfio_noiommu_group_alloc to allocate a fake
single-device iommu group for mediated devices by factoring out a common
function, and replacing the noiommu boolean field in struct vfio_group
with an enum to distinguish the three different kinds of groups.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20210924155705.4258-8-hch@lst.de
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-09-30 12:46:44 -06:00
Linus Torvalds
89b6b8cd92 VFIO update for v5.15-rc1
- Fix dma-valid return WAITED implementation (Anthony Yznaga)
 
  - SPDX license cleanups (Cai Huoqing)
 
  - Split vfio-pci-core from vfio-pci and enhance PCI driver matching
    to support future vendor provided vfio-pci variants (Yishai Hadas,
    Max Gurtovoy, Jason Gunthorpe)
 
  - Replace duplicated reflck with core support for managing first
    open, last close, and device sets (Jason Gunthorpe, Max Gurtovoy,
    Yishai Hadas)
 
  - Fix non-modular mdev support and don't nag about request callback
    support (Christoph Hellwig)
 
  - Add semaphore to protect instruction intercept handler and replace
    open-coded locks in vfio-ap driver (Tony Krowiak)
 
  - Convert vfio-ap to vfio_register_group_dev() API (Jason Gunthorpe)
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Merge tag 'vfio-v5.15-rc1' of git://github.com/awilliam/linux-vfio

Pull VFIO updates from Alex Williamson:

 - Fix dma-valid return WAITED implementation (Anthony Yznaga)

 - SPDX license cleanups (Cai Huoqing)

 - Split vfio-pci-core from vfio-pci and enhance PCI driver matching to
   support future vendor provided vfio-pci variants (Yishai Hadas, Max
   Gurtovoy, Jason Gunthorpe)

 - Replace duplicated reflck with core support for managing first open,
   last close, and device sets (Jason Gunthorpe, Max Gurtovoy, Yishai
   Hadas)

 - Fix non-modular mdev support and don't nag about request callback
   support (Christoph Hellwig)

 - Add semaphore to protect instruction intercept handler and replace
   open-coded locks in vfio-ap driver (Tony Krowiak)

 - Convert vfio-ap to vfio_register_group_dev() API (Jason Gunthorpe)

* tag 'vfio-v5.15-rc1' of git://github.com/awilliam/linux-vfio: (37 commits)
  vfio/pci: Introduce vfio_pci_core.ko
  vfio: Use kconfig if XX/endif blocks instead of repeating 'depends on'
  vfio: Use select for eventfd
  PCI / VFIO: Add 'override_only' support for VFIO PCI sub system
  PCI: Add 'override_only' field to struct pci_device_id
  vfio/pci: Move module parameters to vfio_pci.c
  vfio/pci: Move igd initialization to vfio_pci.c
  vfio/pci: Split the pci_driver code out of vfio_pci_core.c
  vfio/pci: Include vfio header in vfio_pci_core.h
  vfio/pci: Rename ops functions to fit core namings
  vfio/pci: Rename vfio_pci_device to vfio_pci_core_device
  vfio/pci: Rename vfio_pci_private.h to vfio_pci_core.h
  vfio/pci: Rename vfio_pci.c to vfio_pci_core.c
  vfio/ap_ops: Convert to use vfio_register_group_dev()
  s390/vfio-ap: replace open coded locks for VFIO_GROUP_NOTIFY_SET_KVM notification
  s390/vfio-ap: r/w lock for PQAP interception handler function pointer
  vfio/type1: Fix vfio_find_dma_valid return
  vfio-pci/zdev: Remove repeated verbose license text
  vfio: platform: reset: Convert to SPDX identifier
  vfio: Remove struct vfio_device_ops open/release
  ...
2021-09-02 13:41:33 -07:00
Jason Gunthorpe
85c94dcffc vfio: Use kconfig if XX/endif blocks instead of repeating 'depends on'
This results in less kconfig wordage and a simpler understanding of the
required "depends on" to create the menu structure.

The next patch increases the nesting level a lot so this is a nice
preparatory simplification.

Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20210826103912.128972-13-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-08-26 10:36:51 -06:00
Jason Gunthorpe
eb24c1007e vfio: Remove struct vfio_device_ops open/release
Nothing uses this anymore, delete it.

Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Link: https://lore.kernel.org/r/14-v4-9ea22c5e6afb+1adf-vfio_reflck_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-08-11 09:50:11 -06:00
Jason Gunthorpe
2fd585f4ed vfio: Provide better generic support for open/release vfio_device_ops
Currently the driver ops have an open/release pair that is called once
each time a device FD is opened or closed. Add an additional set of
open/close_device() ops which are called when the device FD is opened for
the first time and closed for the last time.

An analysis shows that all of the drivers require this semantic. Some are
open coding it as part of their reflck implementation, and some are just
buggy and miss it completely.

To retain the current semantics PCI and FSL depend on, introduce the idea
of a "device set" which is a grouping of vfio_device's that share the same
lock around opening.

The device set is established by providing a 'set_id' pointer. All
vfio_device's that provide the same pointer will be joined to the same
singleton memory and lock across the whole set. This effectively replaces
the oddly named reflck.

After conversion the set_id will be sourced from:
 - A struct device from a fsl_mc_device (fsl)
 - A struct pci_slot (pci)
 - A struct pci_bus (pci)
 - The struct vfio_device (everything)

The design ensures that the above pointers are live as long as the
vfio_device is registered, so they form reliable unique keys to group
vfio_devices into sets.

This implementation uses xarray instead of searching through the driver
core structures, which simplifies the somewhat tricky locking in this
area.

Following patches convert all the drivers.

Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/4-v4-9ea22c5e6afb+1adf-vfio_reflck_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-08-11 09:50:10 -06:00
Max Gurtovoy
ae03c3771b vfio: Introduce a vfio_uninit_group_dev() API call
This pairs with vfio_init_group_dev() and allows undoing any state that is
stored in the vfio_device unrelated to registration. Add appropriately
placed calls to all the drivers.

The following patch will use this to add pre-registration state for the
device set.

Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/3-v4-9ea22c5e6afb+1adf-vfio_reflck_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-08-11 09:50:10 -06:00
Christoph Hellwig
3fb1712d85 vfio/mdev: don't warn if ->request is not set
Only a single driver actually sets the ->request method, so don't print
a scary warning if it isn't.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20210726143524.155779-3-hch@lst.de
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-08-02 15:23:43 -06:00
Christoph Hellwig
15a5896e61 vfio/mdev: turn mdev_init into a subsys_initcall
Without this setups with buіlt-in mdev and mdev-drivers fail to
register like this:

[1.903149] Driver 'intel_vgpu_mdev' was unable to register with bus_type 'mdev' because the bus was not initialized.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20210726143524.155779-2-hch@lst.de
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-08-02 15:23:43 -06:00
Uwe Kleine-König
fc7a6209d5 bus: Make remove callback return void
The driver core ignores the return value of this callback because there
is only little it can do when a device disappears.

This is the final bit of a long lasting cleanup quest where several
buses were converted to also return void from their remove callback.
Additionally some resource leaks were fixed that were caused by drivers
returning an error code in the expectation that the driver won't go
away.

With struct bus_type::remove returning void it's prevented that newly
implemented buses return an ignored error code and so don't anticipate
wrong expectations for driver authors.

Reviewed-by: Tom Rix <trix@redhat.com> (For fpga)
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Cornelia Huck <cohuck@redhat.com> (For drivers/s390 and drivers/vfio)
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> (For ARM, Amba and related parts)
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Chen-Yu Tsai <wens@csie.org> (for sunxi-rsb)
Acked-by: Pali Rohár <pali@kernel.org>
Acked-by: Mauro Carvalho Chehab <mchehab@kernel.org> (for media)
Acked-by: Hans de Goede <hdegoede@redhat.com> (For drivers/platform)
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-By: Vinod Koul <vkoul@kernel.org>
Acked-by: Juergen Gross <jgross@suse.com> (For xen)
Acked-by: Lee Jones <lee.jones@linaro.org> (For mfd)
Acked-by: Johannes Thumshirn <jth@kernel.org> (For mcb)
Acked-by: Johan Hovold <johan@kernel.org>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> (For slimbus)
Acked-by: Kirti Wankhede <kwankhede@nvidia.com> (For vfio)
Acked-by: Maximilian Luz <luzmaximilian@gmail.com>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> (For ulpi and typec)
Acked-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com> (For ipack)
Acked-by: Geoff Levand <geoff@infradead.org> (For ps3)
Acked-by: Yehezkel Bernat <YehezkelShB@gmail.com> (For thunderbolt)
Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> (For intel_th)
Acked-by: Dominik Brodowski <linux@dominikbrodowski.net> (For pcmcia)
Acked-by: Rafael J. Wysocki <rafael@kernel.org> (For ACPI)
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org> (rpmsg and apr)
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> (For intel-ish-hid)
Acked-by: Dan Williams <dan.j.williams@intel.com> (For CXL, DAX, and NVDIMM)
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com> (For isa)
Acked-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (For firewire)
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> (For hid)
Acked-by: Thorsten Scherer <t.scherer@eckelmann.de> (For siox)
Acked-by: Sven Van Asbroeck <TheSven73@gmail.com> (For anybuss)
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> (For MMC)
Acked-by: Wolfram Sang <wsa@kernel.org> # for I2C
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Finn Thain <fthain@linux-m68k.org>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20210713193522.1770306-6-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-21 11:53:42 +02:00
Alex Williamson
bc01b7617d Merge branch 'hch-mdev-direct-v4' into v5.14/vfio/next 2021-06-21 15:29:51 -06:00
Jason Gunthorpe
88a21f265c vfio/mdev: Allow the mdev_parent_ops to specify the device driver to bind
This allows a mdev driver to opt out of using vfio_mdev.c, instead the
driver will provide a 'struct mdev_driver' and register directly with the
driver core.

Much of mdev_parent_ops becomes unused in this mode:
- create()/remove() are done via the mdev_driver probe()/remove()
- mdev_attr_groups becomes mdev_driver driver.dev_groups
- Wrapper function callbacks are replaced with the same ones from
  struct vfio_device_ops

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/20210617142218.1877096-8-hch@lst.de
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-06-21 15:29:25 -06:00
Jason Gunthorpe
af3ab3f9b9 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>
2021-06-21 15:29:25 -06:00
Max Gurtovoy
9dcf01d957 vfio: centralize module refcount in subsystem layer
Remove code duplication and move module refcounting to the subsystem
module.

Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Link: https://lore.kernel.org/r/20210518192133.59195-2-mgurtovoy@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-06-15 14:12:15 -06:00
Jason Gunthorpe
9169cff168 vfio/mdev: Correct the function signatures for the mdev_type_attributes
The driver core standard is to pass in the properly typed object, the
properly typed attribute and the buffer data. It stems from the root
kobject method:

  ssize_t (*show)(struct kobject *kobj, struct kobj_attribute *attr,..)

Each subclass of kobject should provide their own function with the same
signature but more specific types, eg struct device uses:

  ssize_t (*show)(struct device *dev, struct device_attribute *attr,..)

In this case the existing signature is:

  ssize_t (*show)(struct kobject *kobj, struct device *dev,..)

Where kobj is a 'struct mdev_type *' and dev is 'mdev_type->parent->dev'.

Change the mdev_type related sysfs attribute functions to:

  ssize_t (*show)(struct mdev_type *mtype, struct mdev_type_attribute *attr,..)

In order to restore type safety and match the driver core standard

There are no current users of 'attr', but if it is ever needed it would be
hard to add in retroactively, so do it now.

Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Message-Id: <18-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-12 10:36:00 -06:00
Jason Gunthorpe
c2ef2f50ad vfio/mdev: Remove kobj from mdev_parent_ops->create()
The kobj here is a type-erased version of mdev_type, which is already
stored in the struct mdev_device being passed in. It was only ever used to
compute the type_group_id, which is now extracted directly from the mdev.

Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Message-Id: <17-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-12 10:36:00 -06:00
Jason Gunthorpe
15fcc44be0 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>
2021-04-07 15:39:18 -06:00
Jason Gunthorpe
fbea432390 vfio/mdev: Remove duplicate storage of parent in mdev_device
mdev_device->type->parent is the same thing.

The struct mdev_device was relying on the kref on the mdev_parent to also
indirectly hold a kref on the mdev_type pointer. Now that the type holds a
kref on the parent we can directly kref the mdev_type and remove this
implicit relationship.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Message-Id: <10-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-07 15:39:18 -06:00
Jason Gunthorpe
18d731242d vfio/mdev: Add missing error handling to dev_set_name()
This can fail, and seems to be a popular target for syzkaller error
injection. Check the error return and unwind with put_device().

Fixes: 7b96953bc6 ("vfio: Mediated device Core driver")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Message-Id: <9-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-07 15:39:18 -06:00
Jason Gunthorpe
fbd0e2b0c3 vfio/mdev: Reorganize mdev_device_create()
Once the memory for the struct mdev_device is allocated it should
immediately be device_initialize()'d and filled in so that put_device()
can always be used to undo the allocation.

Place the mdev_get/put_parent() so that they are clearly protecting the
mdev->parent pointer. Move the final put to the release function so that
the lifetime rules are trivial to understand. Update the goto labels to
follow the normal convention.

Remove mdev_device_free() as the release function via device_put() is now
usable in all cases.

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: <8-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-07 15:39:18 -06:00
Jason Gunthorpe
9a302449a5 vfio/mdev: Add missing reference counting to mdev_type
struct mdev_type holds a pointer to the kref'd object struct mdev_parent,
but doesn't hold the kref. The lifetime of the parent becomes implicit
because parent_remove_sysfs_files() is supposed to remove all the access
before the parent can be freed, but this is very hard to reason about.

Make it obviously correct by adding the missing get.

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: <7-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-07 15:39:17 -06:00
Jason Gunthorpe
a9f8111d0b 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>
2021-04-07 15:39:17 -06:00
Jason Gunthorpe
417fd5bf24 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>
2021-04-07 15:39:17 -06:00
Jason Gunthorpe
91b9969d9c vfio/mdev: Simplify driver registration
This is only done once, we don't need to generate code to initialize a
structure stored in the ELF .data segment. Fill in the three required
.driver members directly instead of copying data into them during
mdev_register_driver().

Further the to_mdev_driver() function doesn't belong in a public header,
just inline it into the two places that need it. Finally, we can now
clearly see that 'drv' derived from dev->driver cannot be NULL, firstly
because the driver core forbids it, and secondly because NULL won't pass
through the container_of(). Remove the dead code.

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: <4-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-07 15:39:16 -06:00
Jason Gunthorpe
2a3d15f270 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>
2021-04-07 15:39:16 -06:00
Jason Gunthorpe
b5a1f8921d vfio/mdev: Do not allow a mdev_type to have a NULL parent pointer
There is a small race where the parent is NULL even though the kobj has
already been made visible in sysfs.

For instance the attribute_group is made visible in sysfs_create_files()
and the mdev_type_attr_show() does:

    ret = attr->show(kobj, type->parent->dev, buf);

Which will crash on NULL parent. Move the parent setup to before the type
pointer leaves the stack frame.

Fixes: 7b96953bc6 ("vfio: Mediated device Core driver")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Message-Id: <2-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-07 15:39:16 -06:00
Alex Williamson
6a2a235aa6 Merge branches 'v5.13/vfio/embed-vfio_device', 'v5.13/vfio/misc' and 'v5.13/vfio/nvlink' into v5.13/vfio/next
Spelling fixes merged with file deletion.

Conflicts:
	drivers/vfio/pci/vfio_pci_nvlink2.c

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-06 12:01:51 -06:00
Jason Gunthorpe
1e04ec1420 vfio: Remove device_data from the vfio bus driver API
There are no longer any users, so it can go away. Everything is using
container_of now.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Message-Id: <14-v3-225de1400dfc+4e074-vfio1_jgg@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-06 11:55:11 -06:00
Jason Gunthorpe
6df62c5b05 vfio: Make vfio_device_ops pass a 'struct vfio_device *' instead of 'void *'
This is the standard kernel pattern, the ops associated with a struct get
the struct pointer in for typesafety. The expected design is to use
container_of to cleanly go from the subsystem level type to the driver
level type without having any type erasure in a void *.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Message-Id: <12-v3-225de1400dfc+4e074-vfio1_jgg@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-06 11:55:11 -06:00
Jason Gunthorpe
66873b5fa7 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: 99e3123e3d ("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>
2021-04-06 11:55:11 -06:00
Jason Gunthorpe
1ae1b20f6f vfio/mdev: Use vfio_init/register/unregister_group_dev
mdev gets little benefit because it doesn't actually do anything, however
it is the last user, so move the vfio_init/register/unregister_group_dev()
code here for now.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Liu Yi L <yi.l.liu@intel.com>
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: <10-v3-225de1400dfc+4e074-vfio1_jgg@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-06 11:55:11 -06:00
Zhen Lei
d0a7541dd9 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>
2021-04-06 11:53:50 -06:00
Eric Farman
a15ac665b9 vfio-mdev: Wire in a request handler for mdev parent
While performing some destructive tests with vfio-ccw, where the
paths to a device are forcible removed and thus the device itself
is unreachable, it is rather easy to end up in an endless loop in
vfio_del_group_dev() due to the lack of a request callback for the
associated device.

In this example, one MDEV (77c) is used by a guest, while another
(77b) is not. The symptom is that the iommu is detached from the
mdev for 77b, but not 77c, until that guest is shutdown:

    [  238.794867] vfio_ccw 0.0.077b: MDEV: Unregistering
    [  238.794996] vfio_mdev 11f2d2bc-4083-431d-a023-eff72715c4f0: Removing from iommu group 2
    [  238.795001] vfio_mdev 11f2d2bc-4083-431d-a023-eff72715c4f0: MDEV: detaching iommu
    [  238.795036] vfio_ccw 0.0.077c: MDEV: Unregistering
    ...silence...

Let's wire in the request call back to the mdev device, so that a
device being physically removed from the host can be (gracefully?)
handled by the parent device at the time the device is removed.

Add a message when registering the device if a driver doesn't
provide this callback, so a clue is given that this same loop
may be encountered in a similar situation, and a message when
this occurs instead of the awkward silence noted above.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-12-03 16:21:07 -07:00
Qiushi Wu
aa8ba13cae vfio/mdev: Fix reference count leak in add_mdev_supported_type
kobject_init_and_add() takes reference even when it fails.
If this function returns an error, kobject_put() must be called to
properly clean up the memory associated with the object. Thus,
replace kfree() by kobject_put() to fix this issue. Previous
commit "b8eb718348b8" fixed a similar problem.

Fixes: 7b96953bc6 ("vfio: Mediated device Core driver")
Signed-off-by: Qiushi Wu <wu000273@umn.edu>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-05-29 16:07:18 -06:00
Ben Dooks (Codethink)
e10b4f6cd8 vfio/mdev: make create attribute static
The create attribute is not exported, so make it
static to avoid the following sparse warning:

drivers/vfio/mdev/mdev_sysfs.c:77:1: warning: symbol 'mdev_type_attr_create' was not declared. Should it be static?

Signed-off-by: Ben Dooks (Codethink) <ben.dooks@codethink.co.uk>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-01-09 11:30:57 -07:00
Linus Torvalds
37d4607ebb VFIO updates for v5.3-rc1
- Static symbol cleanup in mdev samples (Kefeng Wang)
 
  - Use vma help in nvlink code (Peng Hao)
 
  - Remove unused code in mbochs sample (YueHaibing)
 
  - Send uevents around mdev registration (Alex Williamson)
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Merge tag 'vfio-v5.3-rc1' of git://github.com/awilliam/linux-vfio

Pull VFIO updates from Alex Williamson:

 - Static symbol cleanup in mdev samples (Kefeng Wang)

 - Use vma help in nvlink code (Peng Hao)

 - Remove unused code in mbochs sample (YueHaibing)

 - Send uevents around mdev registration (Alex Williamson)

* tag 'vfio-v5.3-rc1' of git://github.com/awilliam/linux-vfio:
  mdev: Send uevents around parent device registration
  sample/mdev/mbochs: remove set but not used variable 'mdev_state'
  vfio: vfio_pci_nvlink2: use a vma helper function
  vfio-mdev/samples: make some symbols static
2019-07-17 11:23:13 -07:00
Mauro Carvalho Chehab
baa293e954 docs: driver-api: add a series of orphaned documents
There are lots of documents under Documentation/*.txt and a few other
orphan documents elsehwere that belong to the driver-API book.

Move them to their right place.

Reviewed-by: Cornelia Huck <cohuck@redhat.com> # vfio-related parts
Acked-by: Logan Gunthorpe <logang@deltatee.com> # switchtec
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2019-07-15 11:03:02 -03:00
Alex Williamson
1e4d09d221 mdev: Send uevents around parent device registration
This allows udev to trigger rules when a parent device is registered
or unregistered from mdev.

Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2019-07-11 13:26:52 -06:00
Thomas Gleixner
d2912cb15b 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>
2019-06-19 17:09:55 +02:00
Parav Pandit
5715c4dd66 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: 7b96953bc6 ("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>
2019-06-06 12:32:37 -06:00
Parav Pandit
26c9e3988e vfio/mdev: Avoid creating sysfs remove file on stale device removal
If device is removal is initiated by two threads as below, mdev core
attempts to create a syfs remove file on stale device.
During this flow, below [1] call trace is observed.

     cpu-0                                    cpu-1
     -----                                    -----
  mdev_unregister_device()
    device_for_each_child
       mdev_device_remove_cb
          mdev_device_remove
                                       user_syscall
                                         remove_store()
                                           mdev_device_remove()
                                        [..]
   unregister device();
                                       /* not found in list or
                                        * active=false.
                                        */
                                          sysfs_create_file()
                                          ..Call trace

Now that mdev core follows correct device removal sequence of the linux
bus model, remove shouldn't fail in normal cases. If it fails, there is
no point of creating a stale file or checking for specific error status.

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

Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2019-06-06 12:32:37 -06:00
Parav Pandit
522ecce08a 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>
2019-06-06 10:52:32 -06:00
Thomas Gleixner
ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
Linus Torvalds
a13f065550 IOMMU Updates for Linux v5.2
Including:
 
 	- 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.
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Merge tag 'iommu-updates-v5.2' of 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
  ...
2019-05-13 09:23:18 -04:00
Parav Pandit
405ecbf72f vfio/mdev: Avoid inline get and put parent helpers
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>
2019-05-07 11:23:13 -06:00
Parav Pandit
6093e348a5 vfio/mdev: Fix aborting mdev child device removal if one fails
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: 7b96953bc6 ("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>
2019-05-07 11:23:13 -06:00
Parav Pandit
a6d6f4f160 vfio/mdev: Follow correct remove sequence
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: 6a62c1dfb5 ("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>
2019-05-07 11:23:13 -06:00
Parav Pandit
d300046350 vfio/mdev: Avoid masking error code to EBUSY
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>
2019-05-07 11:23:13 -06:00
Parav Pandit
f707d837b6 vfio/mdev: Removed unused kref
Remove unused kref from the mdev_device structure.

Fixes: 7b96953bc6 ("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>
2019-05-07 11:23:13 -06:00
Parav Pandit
60e7f2c3fe vfio/mdev: Avoid release parent reference during error path
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: 7b96953bc6 ("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>
2019-05-07 11:23:13 -06:00
Lu Baolu
8ac13175cb 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>
2019-04-12 13:00:37 +02:00