From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932311AbeDCNE2 (ORCPT ); Tue, 3 Apr 2018 09:04:28 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:48494 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932153AbeDCNE0 (ORCPT ); Tue, 3 Apr 2018 09:04:26 -0400 Subject: Re: [PATCH v3 05/14] s390: vfio-ap: base implementation of VFIO AP device driver To: Cornelia Huck Cc: linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, freude@de.ibm.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, borntraeger@de.ibm.com, kwankhede@nvidia.com, bjsdjshi@linux.vnet.ibm.com, pbonzini@redhat.com, alex.williamson@redhat.com, pmorel@linux.vnet.ibm.com, alifm@linux.vnet.ibm.com, mjrosato@linux.vnet.ibm.com, jjherne@linux.vnet.ibm.com, thuth@redhat.com, pasic@linux.vnet.ibm.com, berrange@redhat.com, fiuczy@linux.vnet.ibm.com, buendgen@de.ibm.com, akrowiak@linux.vnet.ibm.com References: <1521051954-25715-1-git-send-email-akrowiak@linux.vnet.ibm.com> <1521051954-25715-6-git-send-email-akrowiak@linux.vnet.ibm.com> <20180403125737.15cb55fb.cohuck@redhat.com> From: Tony Krowiak Date: Tue, 3 Apr 2018 09:02:24 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.0 MIME-Version: 1.0 In-Reply-To: <20180403125737.15cb55fb.cohuck@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US X-TM-AS-GCONF: 00 x-cbid: 18040313-0028-0000-0000-00000963DFF1 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00008795; HX=3.00000241; KW=3.00000007; PH=3.00000004; SC=3.00000255; SDB=6.01012509; UDB=6.00516031; IPR=6.00791774; MB=3.00020390; MTD=3.00000008; XFM=3.00000015; UTC=2018-04-03 13:02:30 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18040313-0029-0000-0000-00003A38F6B6 Message-Id: X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2018-04-03_05:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1011 lowpriorityscore=0 impostorscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1709140000 definitions=main-1804030138 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/03/2018 06:57 AM, Cornelia Huck wrote: > On Wed, 14 Mar 2018 14:25:45 -0400 > Tony Krowiak 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 >> --- >> 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. 2017 > Update to 2018? Okay, will do. > >> + * >> + * Author(s): Tony Krowiak >> + */ >> + >> +#include >> +#include >> +#include >> + >> +#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; >> +}