| Message ID | 1521051954-25715-6-git-send-email-akrowiak@linux.vnet.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 14/03/2018 19:25, 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 <akrowiak@linux.vnet.ibm.com> > --- > 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/MAINTAINERS b/MAINTAINERS > index 72742d5..f129253 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -11884,6 +11884,8 @@ W: http://www.ibm.com/developerworks/linux/linux390/ > S: Supported > F: arch/s390/include/asm/kvm/kvm-ap.h > F: arch/s390/kvm/kvm-ap.c > +F: drivers/s390/crypto/vfio_ap_drv.c > +F: drivers/s390/crypto/vfio_ap_private.h > > S390 ZFCP DRIVER > M: Steffen Maier <maier@linux.vnet.ibm.com> > diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig > index cbe1d97..58509db 100644 > --- a/arch/s390/Kconfig > +++ b/arch/s390/Kconfig > @@ -771,6 +771,17 @@ config VFIO_CCW > To compile this driver as a module, choose M here: the > module will be called vfio_ccw. > > +config VFIO_AP > + def_tristate m not sure it must be module by default. I would not set it by default. > + prompt "VFIO support for AP devices" > + depends on ZCRYPT && VFIO_MDEV_DEVICE VFIO_MDEV_DEVICE is a general feature *needed* by VFIO_AP and has no use case by its own. If it is set it is obviously because some mediated device drivers needs it. while ZCRYPT is a Z feature which may be set without VFIO_AP. So you need: config VFIO_AP def_tristate n prompt "VFIO support for AP devices" depends on ZCRYPT select VFIO_MDEV select VFIO_MDEV_DEVICE ... Pierre
On 03/15/2018 09:25 AM, Pierre Morel wrote: > On 14/03/2018 19:25, 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 <akrowiak@linux.vnet.ibm.com> >> --- >> 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/MAINTAINERS b/MAINTAINERS >> index 72742d5..f129253 100644 >> --- a/MAINTAINERS >> +++ b/MAINTAINERS >> @@ -11884,6 +11884,8 @@ W: >> http://www.ibm.com/developerworks/linux/linux390/ >> S: Supported >> F: arch/s390/include/asm/kvm/kvm-ap.h >> F: arch/s390/kvm/kvm-ap.c >> +F: drivers/s390/crypto/vfio_ap_drv.c >> +F: drivers/s390/crypto/vfio_ap_private.h >> >> S390 ZFCP DRIVER >> M: Steffen Maier <maier@linux.vnet.ibm.com> >> diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig >> index cbe1d97..58509db 100644 >> --- a/arch/s390/Kconfig >> +++ b/arch/s390/Kconfig >> @@ -771,6 +771,17 @@ config VFIO_CCW >> To compile this driver as a module, choose M here: the >> module will be called vfio_ccw. >> >> +config VFIO_AP >> + def_tristate m > not sure it must be module by default. > I would not set it by default. Connie also asked about this in the last review, so I will go ahead and change it. > >> + prompt "VFIO support for AP devices" >> + depends on ZCRYPT && VFIO_MDEV_DEVICE > > VFIO_MDEV_DEVICE is a general feature *needed* by VFIO_AP > and has no use case by its own. If it is set it is obviously because some > mediated device drivers needs it. > while ZCRYPT is a Z feature which may be set without VFIO_AP. > > So you need: > > config VFIO_AP > def_tristate n > prompt "VFIO support for AP devices" > depends on ZCRYPT > select VFIO_MDEV > select VFIO_MDEV_DEVICE > ... I was thinking the same just yesterday and I agree, this makes sense. > > > > Pierre >
On Thu, 15 Mar 2018 13:25:25 -0400 Tony Krowiak <akrowiak@linux.vnet.ibm.com> wrote: > On 03/15/2018 09:25 AM, Pierre Morel wrote: > > On 14/03/2018 19:25, Tony Krowiak wrote: > >> +config VFIO_AP > >> + def_tristate m > > not sure it must be module by default. > > I would not set it by default. > Connie also asked about this in the last review, so I will go ahead > and change it. > > > >> + prompt "VFIO support for AP devices" > >> + depends on ZCRYPT && VFIO_MDEV_DEVICE > > > > VFIO_MDEV_DEVICE is a general feature *needed* by VFIO_AP > > and has no use case by its own. If it is set it is obviously because some > > mediated device drivers needs it. > > while ZCRYPT is a Z feature which may be set without VFIO_AP. > > > > So you need: > > > > config VFIO_AP > > def_tristate n > > prompt "VFIO support for AP devices" > > depends on ZCRYPT > > select VFIO_MDEV > > select VFIO_MDEV_DEVICE > > ... > I was thinking the same just yesterday and I agree, this makes sense. OTOH, nobody else seems to do a select on these symbols so far. If you decide to go that route, you'll also need to depend on VFIO (otherwise you could end up selecting symbols with unmet dependencies). All in all, I prefer the 'depends' approach.
On 27/03/2018 13:17, Cornelia Huck wrote: > On Thu, 15 Mar 2018 13:25:25 -0400 > Tony Krowiak <akrowiak@linux.vnet.ibm.com> wrote: > >> On 03/15/2018 09:25 AM, Pierre Morel wrote: >>> On 14/03/2018 19:25, Tony Krowiak wrote: >>>> +config VFIO_AP >>>> + def_tristate m >>> not sure it must be module by default. >>> I would not set it by default. >> Connie also asked about this in the last review, so I will go ahead >> and change it. >>> >>>> + prompt "VFIO support for AP devices" >>>> + depends on ZCRYPT && VFIO_MDEV_DEVICE >>> VFIO_MDEV_DEVICE is a general feature *needed* by VFIO_AP >>> and has no use case by its own. If it is set it is obviously because some >>> mediated device drivers needs it. >>> while ZCRYPT is a Z feature which may be set without VFIO_AP. >>> >>> So you need: >>> >>> config VFIO_AP >>> def_tristate n >>> prompt "VFIO support for AP devices" >>> depends on ZCRYPT >>> select VFIO_MDEV >>> select VFIO_MDEV_DEVICE >>> ... >> I was thinking the same just yesterday and I agree, this makes sense. > OTOH, nobody else seems to do a select on these symbols so far. > > If you decide to go that route, you'll also need to depend on VFIO I think a select is better (again). > (otherwise you could end up selecting symbols with unmet dependencies). > All in all, I prefer the 'depends' approach. > Why do you prefer this approach? I can tell you why I prefer a mixed approach: We have two tools, depends and select. It seems to me that depends should be used for things we can not choose to be there or not, but things that just are there, like hardware dependencies. For example MMU, CPU type, CRYPTO hardware... Select on the other hand is useful to choose things that we need like libraries, VFIO, VIRTIO, crypto libraries etc. Using this policy is clear and makes easy to choose functionalities and get the utilities automatically. On the other hand, only using depends makes things to hide the functionalities behind the utilities.
On Tue, 27 Mar 2018 16:45:02 +0200 Pierre Morel <pmorel@linux.vnet.ibm.com> wrote: > On 27/03/2018 13:17, Cornelia Huck wrote: > > On Thu, 15 Mar 2018 13:25:25 -0400 > > Tony Krowiak <akrowiak@linux.vnet.ibm.com> wrote: > > > >> On 03/15/2018 09:25 AM, Pierre Morel wrote: > >>> On 14/03/2018 19:25, Tony Krowiak wrote: > >>>> +config VFIO_AP > >>>> + def_tristate m > >>> not sure it must be module by default. > >>> I would not set it by default. > >> Connie also asked about this in the last review, so I will go ahead > >> and change it. > >>> > >>>> + prompt "VFIO support for AP devices" > >>>> + depends on ZCRYPT && VFIO_MDEV_DEVICE > >>> VFIO_MDEV_DEVICE is a general feature *needed* by VFIO_AP > >>> and has no use case by its own. If it is set it is obviously because some > >>> mediated device drivers needs it. > >>> while ZCRYPT is a Z feature which may be set without VFIO_AP. > >>> > >>> So you need: > >>> > >>> config VFIO_AP > >>> def_tristate n > >>> prompt "VFIO support for AP devices" > >>> depends on ZCRYPT > >>> select VFIO_MDEV > >>> select VFIO_MDEV_DEVICE > >>> ... > >> I was thinking the same just yesterday and I agree, this makes sense. > > OTOH, nobody else seems to do a select on these symbols so far. > > > > If you decide to go that route, you'll also need to depend on VFIO > > I think a select is better (again). > > > (otherwise you could end up selecting symbols with unmet dependencies). > > All in all, I prefer the 'depends' approach. > > > Why do you prefer this approach? Hm, I thought I had already written a mail, but apparently I didn't.... > I can tell you why I prefer a mixed approach: > > We have two tools, depends and select. > > It seems to me that depends should be used for things we can not choose > to be there or not, but things that just are there, like hardware > dependencies. For example MMU, CPU type, CRYPTO hardware... > > Select on the other hand is useful to choose things that we need like > libraries, VFIO, VIRTIO, crypto libraries etc. > > Using this policy is clear and makes easy to choose functionalities and > get the utilities automatically. > > On the other hand, only using depends makes things to hide the > functionalities behind the utilities. My view is the following: - select is useful for library functionality or for enabling architecture-specific optimizations (the HAVE_xxx symbols), especially things you don't want the user to deal with. If you select something, you need to take care of any dependencies yourself. - depends is useful for more complex dependencies, and especially things you don't want automagically enabled. [In modern menuconfig, it is easy to figure out any missing dependencies for a config option anyway.] The mdev infrastructure is too complex to be considered a simple library IMO (cf. the missing VFIO dependency).
On Wed, 14 Mar 2018 14:25:45 -0400 Tony Krowiak <akrowiak@linux.vnet.ibm.com> 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@linux.vnet.ibm.com> > --- > 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? > + * > + * Author(s): Tony Krowiak <akrowiak@linux.vnet.ibm.com> > + */ > + > +#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) > + 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). > + > +matrix_alloc_err: > + root_device_unregister(vfio_ap_root_device); > + > +done: > + return ret; > +}
On 04/03/2018 06:57 AM, Cornelia Huck wrote: > On Wed, 14 Mar 2018 14:25:45 -0400 > Tony Krowiak <akrowiak@linux.vnet.ibm.com> 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@linux.vnet.ibm.com> >> --- >> 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 <akrowiak@linux.vnet.ibm.com> >> + */ >> + >> +#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; >> +}
diff --git a/MAINTAINERS b/MAINTAINERS index 72742d5..f129253 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -11884,6 +11884,8 @@ W: http://www.ibm.com/developerworks/linux/linux390/ S: Supported F: arch/s390/include/asm/kvm/kvm-ap.h F: arch/s390/kvm/kvm-ap.c +F: drivers/s390/crypto/vfio_ap_drv.c +F: drivers/s390/crypto/vfio_ap_private.h S390 ZFCP DRIVER M: Steffen Maier <maier@linux.vnet.ibm.com> diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index cbe1d97..58509db 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -771,6 +771,17 @@ config VFIO_CCW To compile this driver as a module, choose M here: the module will be called vfio_ccw. +config VFIO_AP + def_tristate m + prompt "VFIO support for AP devices" + depends on ZCRYPT && VFIO_MDEV_DEVICE + help + This driver grants access to Adjunct Processor (AP) devices + via the VFIO mediated device interface. + + To compile this driver as a module, choose M here: the module + will be called vfio_ap. + endmenu menu "Dump support" diff --git a/drivers/s390/crypto/Makefile b/drivers/s390/crypto/Makefile index b59af54..48e466e 100644 --- a/drivers/s390/crypto/Makefile +++ b/drivers/s390/crypto/Makefile @@ -15,3 +15,7 @@ obj-$(CONFIG_ZCRYPT) += zcrypt_pcixcc.o zcrypt_cex2a.o zcrypt_cex4.o # pkey kernel module pkey-objs := pkey_api.o obj-$(CONFIG_PKEY) += pkey.o + +# adjunct processor matrix +vfio_ap-objs := vfio_ap_drv.o +obj-$(CONFIG_VFIO_AP) += vfio_ap.o 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 + * + * Author(s): Tony Krowiak <akrowiak@linux.vnet.ibm.com> + */ + +#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) { + 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); + +matrix_alloc_err: + root_device_unregister(vfio_ap_root_device); + +done: + return ret; +} + +static void vfio_ap_matrix_dev_destroy(struct ap_matrix *ap_matrix) +{ + device_unregister(&ap_matrix->device); + root_device_unregister(vfio_ap_root_device); +} + +int __init vfio_ap_init(void) +{ + int ret; + + ret = vfio_ap_matrix_dev_create(); + if (ret) + return ret; + + memset(&vfio_ap_drv, 0, sizeof(vfio_ap_drv)); + vfio_ap_drv.probe = vfio_ap_queue_dev_probe; + vfio_ap_drv.ids = ap_queue_ids; + + ret = ap_driver_register(&vfio_ap_drv, THIS_MODULE, VFIO_AP_DRV_NAME); + if (ret) { + vfio_ap_matrix_dev_destroy(ap_matrix); + return ret; + } + + return 0; +} + +void __exit vfio_ap_exit(void) +{ + ap_driver_unregister(&vfio_ap_drv); + vfio_ap_matrix_dev_destroy(ap_matrix); +} + +module_init(vfio_ap_init); +module_exit(vfio_ap_exit); diff --git a/drivers/s390/crypto/vfio_ap_private.h b/drivers/s390/crypto/vfio_ap_private.h new file mode 100644 index 0000000..21f3697 --- /dev/null +++ b/drivers/s390/crypto/vfio_ap_private.h @@ -0,0 +1,22 @@ +/* + * Private data and functions for adjunct processor VFIO matrix driver. + * + * Copyright IBM Corp. 2017 + * Author(s): Tony Krowiak <akrowiak@linux.vnet.ibm.com> + */ + +#ifndef _VFIO_AP_PRIVATE_H_ +#define _VFIO_AP_PRIVATE_H_ + +#include <linux/types.h> + +#include "ap_bus.h" + +#define VFIO_AP_MODULE_NAME "vfio_ap" +#define VFIO_AP_DRV_NAME "vfio_ap" + +struct ap_matrix { + struct device device; +}; + +#endif /* _VFIO_AP_PRIVATE_H_ */ diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h index e3301db..cf2a5e9 100644 --- a/include/uapi/linux/vfio.h +++ b/include/uapi/linux/vfio.h @@ -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 */ __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" /** * VFIO_DEVICE_GET_REGION_INFO - _IOWR(VFIO_TYPE, VFIO_BASE + 8,
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@linux.vnet.ibm.com> --- 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