s390: vfio-ap: base implementation of VFIO AP device driver
A message that is not in the archive (sent off-list or not yet received): [email protected]
Quoted 61 lines · Cornelia Huck
Quoted 57 lines · On Thu, 26 Jul 2018 21:54:15 +0200 Christian Borntraeger…
From: Tony Krowiak <[email protected]>
Introduces a new AP device driver. This device driver is built on the VFIO mediated device framework. The framework provides sysfs interfaces that facilitate passthrough access by guests to devices installed on the linux host.
The VFIO AP device driver will serve two purposes:
1. Provide the interfaces to reserve AP devices for exclusive use by KVM guests. This is accomplished by unbinding the devices to be reserved for guest usage from the default AP device driver and binding them to the VFIO AP device driver.
2. Implements the functions, callbacks and sysfs attribute interfaces required to create one or more VFIO mediated devices each of which will be used to configure the AP matrix for a guest and serve as a file descriptor for facilitating communication between QEMU and the VFIO AP device driver.
When the VFIO AP device driver is initialized:
* It registers with the AP bus for control of type 10 (CEX4 and newer) AP queue devices. This limitation was imposed due to:
1. A desire to keep the code as simple as possible;
2. Some older models are no longer supported by the kernel and others are getting close to end of service.
The probe and remove callbacks will be provided to support the binding/unbinding of AP queue devices to/from the VFIO AP device driver.
* Creates a virtual misc device,
/sys/devices/virtual/misc/vfio_ap, device to serve as the parent of the mediated devices created, one for each guest, and to hold the APQNs of the AP devices bound to the VFIO AP device driver.Signed-off-by Tony Krowiak <[email protected]>Reviewed-by Halil Pasic <[email protected]>Tested-by Michael Mueller <[email protected]>Tested-by Farhan Ali <[email protected]>Signed-off-by Christian Borntraeger <[email protected]>--- MAINTAINERS | 10 +++ arch/s390/Kconfig | 11 +++ drivers/s390/crypto/Makefile | 4 + drivers/s390/crypto/vfio_ap_drv.c | 112 ++++++++++++++++++++++++++ drivers/s390/crypto/vfio_ap_private.h | 30 +++++++ include/uapi/linux/vfio.h | 2 + 6 files changed, 169 insertions(+)create mode 100644
drivers/s390/crypto/vfio_ap_drv.ccreate mode 100644drivers/s390/crypto/vfio_ap_private.h
Quoted 9 lines
include/uapi/linux/vfio.h struct vfio_device_info { · line 203
Quoted 9 lines
include/uapi/linux/vfio.h +1
-0@@ -200,6 +200,7 @@ struct vfio_device_info {#define VFIO_DEVICE_FLAGS_PLATFORM (1 << 2)/* vfio-platform device */ #define VFIO_DEVICE_FLAGS_AMBA (1 << 3)/* vfio-amba device */ #define VFIO_DEVICE_FLAGS_CCW (1 << 4)/* vfio-ccw device */ +#define VFIO_DEVICE_FLAGS_AP (1 << 5)/* vfio-ap device */
And this one is also unused for now I guess.
Quoted 9 lines
Quoted 9 lines
include/uapi/linux/vfio.h +1
-0__u32 num_regions;/* Max region index + 1 */ __u32 num_irqs;/* Max IRQ index + 1 */ };@@ -215,6 +216,7 @@ struct vfio_device_info {#define VFIO_DEVICE_API_PLATFORM_STRING "vfio-platform"#define VFIO_DEVICE_API_AMBA_STRING "vfio-amba"#define VFIO_DEVICE_API_CCW_STRING "vfio-ccw" +#define VFIO_DEVICE_API_AP_STRING "vfio-ap"
Quoted 5 lines
include/uapi/linux/vfio.h struct vfio_device_info { · line 222
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include/uapi/linux/vfio.h +0
-0/** * VFIO_DEVICE_GET_REGION_INFO - _IOWR(VFIO_TYPE, VFIO_BASE + 8, Should this hunk go into the next patch?
Yes.