On 04/03/2018 06:57 AM, Cornelia Huck wrote:
On Wed, 14 Mar 2018 14:25:45 -0400 Tony Krowiak <akrowiak@xxxxxxxxxxxxxxxxxx> wrote: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. 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 /sys/devices/vfio-ap/matrix device to hold the APQNs of the AP devices bound to the VFIO AP device driver and serves as the parent of the mediated devices created for each guest. Signed-off-by: Tony Krowiak <akrowiak@xxxxxxxxxxxxxxxxxx> --- MAINTAINERS | 2 + arch/s390/Kconfig | 11 +++ drivers/s390/crypto/Makefile | 4 + drivers/s390/crypto/vfio_ap_drv.c | 135 +++++++++++++++++++++++++++++++++ drivers/s390/crypto/vfio_ap_private.h | 22 ++++++ include/uapi/linux/vfio.h | 2 + 6 files changed, 176 insertions(+), 0 deletions(-) create mode 100644 drivers/s390/crypto/vfio_ap_drv.c create mode 100644 drivers/s390/crypto/vfio_ap_private.h diff --git a/drivers/s390/crypto/vfio_ap_drv.c b/drivers/s390/crypto/vfio_ap_drv.c new file mode 100644 index 0000000..459e595 --- /dev/null +++ b/drivers/s390/crypto/vfio_ap_drv.c @@ -0,0 +1,135 @@ +/* + * VFIO based AP device driver + * + * Copyright IBM Corp. 2017Update to 2018?
Okay, will do.
+ * + * Author(s): Tony Krowiak <akrowiak@xxxxxxxxxxxxxxxxxx> + */ + +#include <linux/module.h> +#include <linux/mod_devicetable.h> +#include <linux/slab.h> + +#include "vfio_ap_private.h" + +#define VFIO_AP_ROOT_NAME "vfio_ap" +#define VFIO_AP_DEV_TYPE_NAME "ap_matrix" +#define VFIO_AP_DEV_NAME "matrix" + +MODULE_AUTHOR("IBM Corporation"); +MODULE_DESCRIPTION("VFIO AP device driver, Copyright IBM Corp. 2017"); +MODULE_LICENSE("GPL v2"); + +static struct device *vfio_ap_root_device; + +static struct ap_driver vfio_ap_drv; + +static struct ap_matrix *ap_matrix; + +static struct device_type vfio_ap_dev_type = { + .name = VFIO_AP_DEV_TYPE_NAME, +}; + +/* Only type 10 adapters (CEX4 and later) are supported + * by the AP matrix device driver + */ +static struct ap_device_id ap_queue_ids[] = { + { .dev_type = AP_DEVICE_TYPE_CEX4, + .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE }, + { .dev_type = AP_DEVICE_TYPE_CEX5, + .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE }, + { .dev_type = AP_DEVICE_TYPE_CEX6, + .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE }, + { /* end of sibling */ }, +}; + +MODULE_DEVICE_TABLE(vfio_ap, ap_queue_ids); + +static int vfio_ap_queue_dev_probe(struct ap_device *apdev) +{ + return 0; +} + +static void vfio_ap_matrix_dev_release(struct device *dev) +{ + struct ap_matrix *ap_matrix = dev_get_drvdata(dev); + + kfree(ap_matrix); +} + +static int vfio_ap_matrix_dev_create(void) +{ + int ret; + + vfio_ap_root_device = root_device_register(VFIO_AP_ROOT_NAME); + + ret = IS_ERR(vfio_ap_root_device); + if (ret) {Minor nit: I'd contract that to if (IS_ERR(vfio_ap_root_device)) { (you're writing ret in any case)
Okay, will do.
+ ret = PTR_ERR(vfio_ap_root_device); + goto done; + } + + ap_matrix = kzalloc(sizeof(*ap_matrix), GFP_KERNEL); + if (!ap_matrix) { + ret = -ENOMEM; + goto matrix_alloc_err; + } + + ap_matrix->device.type = &vfio_ap_dev_type; + dev_set_name(&ap_matrix->device, "%s", VFIO_AP_DEV_NAME); + ap_matrix->device.parent = vfio_ap_root_device; + ap_matrix->device.release = vfio_ap_matrix_dev_release; + ap_matrix->device.driver = &vfio_ap_drv.driver; + + ret = device_register(&ap_matrix->device); + if (ret) + goto matrix_reg_err; + + goto done; + +matrix_reg_err: + put_device(&ap_matrix->device); + kfree(ap_matrix);The kfree() is wrong: If you called device_register for the embedded struct device, this needs to be handled via the ->release callback exclusively (IOW, the put_device() is enough and the kfree needs to go).
Ah yes, I see that. I will fix it.
+ +matrix_alloc_err: + root_device_unregister(vfio_ap_root_device); + +done: + return ret; +}
