On Fri, 13 Oct 2017 13:38:53 -0400 Tony Krowiak <akrowiak@xxxxxxxxxxxxxxxxxx> wrote: > Provides the sysfs interfaces for assigning an adapter to > and unassigning an AP adapter from a mediated matrix device. > > The IDs of the AP adapters assigned to the mediated matrix > device are stored in a bit mask. The bits in the mask, from > left to right, correspond to AP adapter numbers 0 to 255. The > bit corresponding to the ID of the adapter being assigned will > be set in the bit mask. > > The relevant sysfs structures are: > > /sys/devices/ap_matrix > ... [matrix] > ...... [mdev_supported_types] > ......... [ap_matrix-passthrough] > ............ [devices] > ...............[$uuid] > .................. adapters > .................. assign_adapter > .................. unassign_adapter > > To assign an adapter to the $uuid mediated matrix device, write > ID of the adapter (hex value) to the assign_adapter file. To > unassign an adapter, write the ID of the adapter (hex value) > to the unassign_adapter file. The list of adapters that have > been assigned can be viewed by displaying the contents of the > adapters file. > > For example, to assign adapter 0xad to mediated matrix device > $uuid: > > echo ad > assign_adapter > > To unassign adapter 0xad: > > echo ad > unassign_adapter > > To see the list of adapters assigned: > > cat adapters > > Signed-off-by: Tony Krowiak <akrowiak@xxxxxxxxxxxxxxxxxx> > --- > arch/s390/include/asm/ap-config.h | 13 +++ > drivers/s390/crypto/vfio_ap_matrix_ops.c | 147 ++++++++++++++++++++++++++++++ > 2 files changed, 160 insertions(+), 0 deletions(-) > > diff --git a/drivers/s390/crypto/vfio_ap_matrix_ops.c b/drivers/s390/crypto/vfio_ap_matrix_ops.c > index 7d01f18..e4b1236 100644 > --- a/drivers/s390/crypto/vfio_ap_matrix_ops.c > +++ b/drivers/s390/crypto/vfio_ap_matrix_ops.c > @@ -23,6 +23,7 @@ > struct ap_matrix_mdev { > struct mdev_device *mdev; > struct list_head node; > + struct ap_config_masks masks; > }; > > struct ap_matrix *matrix; > @@ -136,9 +137,155 @@ static ssize_t device_api_show(struct kobject *kobj, struct device *dev, > NULL, > }; > > +static int ap_matrix_id_is_xnum(char *id) > +{ > + size_t i; > + > + for (i = 0; i < strlen(id); i++) { > + if (!isxdigit(id[i])) > + return 0; > + } > + > + return 1; > +} This feels like something for which an utility function should already exist... > + > +static int ap_matrix_parse_id(const char *buf, unsigned int *id) > +{ > + int ret; > + char *bufcpy; > + char *id_str; > + > + if ((strlen(buf) == 0) || (*buf == '\n')) { > + pr_err("%s: input buffer '%s' contains no valid hex values", > + VFIO_AP_MATRIX_MODULE_NAME, buf); > + return -EINVAL; > + } > + > + bufcpy = kzalloc(strlen(buf) + 1, GFP_KERNEL); > + if (!bufcpy) > + return -ENOMEM; > + > + strcpy(bufcpy, buf); > + id_str = strim(bufcpy); > + > + if (!ap_matrix_id_is_xnum(id_str)) { > + pr_err("%s: input id '%s' contains an invalid hex value '%s'", > + VFIO_AP_MATRIX_MODULE_NAME, buf, id_str); > + ret = -EINVAL; > + goto done; > + } > + > + ret = kstrtouint (id_str, 16, id); > + if (ret || (*id >= AP_MATRIX_MAX_MASK_BITS)) { > + pr_err("%s: input id '%s' is not a value from 0 to %x", > + VFIO_AP_MATRIX_MODULE_NAME, buf, > + AP_MATRIX_MAX_MASK_BITS); > + ret = -EINVAL; > + goto done; > + } > + > + ret = 0; > + > +done: > + kfree(bufcpy); > + return ret; > +} Similarly, I suspect you are not the first person with similar parsing needs. > + > +static ssize_t ap_matrix_adapters_assign(struct device *dev, > + struct device_attribute *attr, > + const char *buf, size_t count) > +{ > + int ret; > + unsigned int apid; > + struct mdev_device *mdev = mdev_from_dev(dev); > + struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); > + > + ret = ap_matrix_parse_id(buf, &apid); > + if (ret) > + return ret; > + > + set_bit_inv((unsigned long)apid, > + (unsigned long *)matrix_mdev->masks.apm); Probably needs a comment regarding byte order of the masks somewhere. > + > + return count; > +} > +static DEVICE_ATTR(assign_adapter, 0644, NULL, ap_matrix_adapters_assign); -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html