The code was allowing platform devices to be used without a supporting
VFIO reset driver. The hardware can be left in some inconsistent state
after a guest machine abort.
The reset driver will put the hardware back to safe state and disable
interrupts before returning the control back to the host machine.
Adding a new reset_required kernel module option to platform VFIO drivers.
The default value is true for the DT and ACPI based drivers.
The reset requirement value for AMBA drivers is set to false and is
unchangeable to maintain the existing functionality.
New requirements are:
1. A reset function needs to be implemented by the corresponding driver
via DT/ACPI.
2. The reset function needs to be discovered via DT/ACPI.
The probe of the driver will fail if any of the above conditions are
not satisfied.
Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The code is using the compatible DT string to associate a reset driver
with the actual device itself. The compatible string does not exist on
ACPI based systems. HID is the unique identifier for a device driver
instead.
Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Renaming the reset function to of_reset as it is only used
by the device tree based platforms.
Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Reviewed-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
It might be helpful for the end-user to check the device reset
function was found by the vfio platform reset framework.
Lets store a pointer to the struct device in vfio_platform_device
and trace when the reset function is called or not found.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Remove the static lookup table and use the dynamic list of registered
reset functions instead. Also load the reset module through its alias.
The reset struct module pointer is stored in vfio_platform_device.
We also remove the useless struct device pointer parameter in
vfio_platform_get_reset.
This patch fixes the issue related to the usage of __symbol_get, which
besides from being moot, prevented compilation with CONFIG_MODULES
disabled.
Also usage of MODULE_ALIAS makes possible to add a new reset module
without needing to update the framework. This was suggested by Arnd.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Let's retrieve the compatibility string on probe and store it
in the vfio_platform_device struct
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The module_vfio_reset_handler macro
- define a module alias
- implement module init/exit function which respectively registers
and unregisters the reset function.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
In preparation for subsequent changes in reset function lookup,
lets introduce a dynamic list of reset combos (compat string,
reset module, reset function). The list can be populated/voided with
vfio_platform_register/unregister_reset. Those are not yet used in
this patch.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
To prepare for vfio platform reset rework let's build
vfio_platform_common.c and vfio_platform_irq.c in a separate
module from vfio-platform and vfio-amba. This makes possible
to have separate module inits and works around a race between
platform driver init and vfio reset module init: that way we
make sure symbols exported by base are available when vfio-platform
driver gets probed.
The open/release being implemented in the base module, the ref
count is applied to the parent module instead.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
A new reset callback is introduced. If this callback is populated,
the reset is invoked on device first open/last close or upon userspace
ioctl. The modality is exposed on VFIO_DEVICE_GET_INFO.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Acked-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Tested-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This patch introduces the vfio_platform_reset_combo struct that
stores all the information useful to handle the reset modality:
compat string, name of the reset function, name of the module that
implements the reset function. A lookup table of such structures
is added, currently void.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Acked-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Tested-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
With this patch the VFIO user will be able to set an eventfd that can be
used in order to mask and unmask IRQs of platform devices.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Level sensitive interrupts are exposed as maskable and automasked
interrupts and are masked and disabled automatically when they fire.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
[Baptiste Reynal: Move masked interrupt initialization from "vfio/platform:
trigger an interrupt via eventfd"]
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This patch allows to set an eventfd for a platform device's interrupt,
and also to trigger the interrupt eventfd from userspace for testing.
Level sensitive interrupts are marked as maskable and are handled in
a later patch. Edge triggered interrupts are not advertised as maskable
and are implemented here using a simple and efficient IRQ handler.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
[Baptiste Reynal: fix masked interrupt initialization]
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This patch is a skeleton for the VFIO_DEVICE_SET_IRQS IOCTL, around which
most IRQ functionality is implemented in VFIO.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Return information for the interrupts exposed by the device.
This patch extends VFIO_DEVICE_GET_INFO with the number of IRQs
and enables VFIO_DEVICE_GET_IRQ_INFO.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
VFIO returns a file descriptor which we can use to manipulate the memory
regions of the device. Usually, the user will mmap memory regions that are
addressable on page boundaries, however for memory regions where this is
not the case we cannot provide mmap functionality due to security concerns.
For this reason we also allow to use read and write functions to the file
descriptor pointing to the memory regions.
We implement this functionality only for MMIO regions of platform devices;
PIO regions are not being handled at this point.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This patch enables the IOCTLs VFIO_DEVICE_GET_REGION_INFO ioctl call,
which allows the user to learn about the available MMIO resources of
a device.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This patch forms the common skeleton code for platform devices support
with VFIO. This will include the core functionality of VFIO_PLATFORM,
however binding to the device and discovering the device resources will
be done with the help of a separate file where any Linux platform bus
specific code will reside.
This will allow us to implement support for also discovering AMBA devices
and their resources, but still reuse a large part of the VFIO_PLATFORM
implementation.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
[Baptiste Reynal: added includes in vfio_platform_private.h]
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Sinan Kaya