diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/s390/crypto/vfio_ap_ops.c | 1328 |
1 files changed, 1328 insertions, 0 deletions
diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c new file mode 100644 index 000000000..72eb8f984 --- /dev/null +++ b/drivers/s390/crypto/vfio_ap_ops.c @@ -0,0 +1,1328 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Adjunct processor matrix VFIO device driver callbacks. + * + * Copyright IBM Corp. 2018 + * + * Author(s): Tony Krowiak <akrowiak@linux.ibm.com> + * Halil Pasic <pasic@linux.ibm.com> + * Pierre Morel <pmorel@linux.ibm.com> + */ +#include <linux/string.h> +#include <linux/vfio.h> +#include <linux/device.h> +#include <linux/list.h> +#include <linux/ctype.h> +#include <linux/bitops.h> +#include <linux/kvm_host.h> +#include <linux/module.h> +#include <asm/kvm.h> +#include <asm/zcrypt.h> + +#include "vfio_ap_private.h" + +#define VFIO_AP_MDEV_TYPE_HWVIRT "passthrough" +#define VFIO_AP_MDEV_NAME_HWVIRT "VFIO AP Passthrough Device" + +static int vfio_ap_mdev_reset_queues(struct mdev_device *mdev); +static struct vfio_ap_queue *vfio_ap_find_queue(int apqn); + +static int match_apqn(struct device *dev, const void *data) +{ + struct vfio_ap_queue *q = dev_get_drvdata(dev); + + return (q->apqn == *(int *)(data)) ? 1 : 0; +} + +/** + * vfio_ap_get_queue: Retrieve a queue with a specific APQN from a list + * @matrix_mdev: the associated mediated matrix + * @apqn: The queue APQN + * + * Retrieve a queue with a specific APQN from the list of the + * devices of the vfio_ap_drv. + * Verify that the APID and the APQI are set in the matrix. + * + * Returns the pointer to the associated vfio_ap_queue + */ +static struct vfio_ap_queue *vfio_ap_get_queue( + struct ap_matrix_mdev *matrix_mdev, + int apqn) +{ + struct vfio_ap_queue *q; + + if (!test_bit_inv(AP_QID_CARD(apqn), matrix_mdev->matrix.apm)) + return NULL; + if (!test_bit_inv(AP_QID_QUEUE(apqn), matrix_mdev->matrix.aqm)) + return NULL; + + q = vfio_ap_find_queue(apqn); + if (q) + q->matrix_mdev = matrix_mdev; + + return q; +} + +/** + * vfio_ap_wait_for_irqclear + * @apqn: The AP Queue number + * + * Checks the IRQ bit for the status of this APQN using ap_tapq. + * Returns if the ap_tapq function succeeded and the bit is clear. + * Returns if ap_tapq function failed with invalid, deconfigured or + * checkstopped AP. + * Otherwise retries up to 5 times after waiting 20ms. + * + */ +static void vfio_ap_wait_for_irqclear(int apqn) +{ + struct ap_queue_status status; + int retry = 5; + + do { + status = ap_tapq(apqn, NULL); + switch (status.response_code) { + case AP_RESPONSE_NORMAL: + case AP_RESPONSE_RESET_IN_PROGRESS: + if (!status.irq_enabled) + return; + fallthrough; + case AP_RESPONSE_BUSY: + msleep(20); + break; + case AP_RESPONSE_Q_NOT_AVAIL: + case AP_RESPONSE_DECONFIGURED: + case AP_RESPONSE_CHECKSTOPPED: + default: + WARN_ONCE(1, "%s: tapq rc %02x: %04x\n", __func__, + status.response_code, apqn); + return; + } + } while (--retry); + + WARN_ONCE(1, "%s: tapq rc %02x: %04x could not clear IR bit\n", + __func__, status.response_code, apqn); +} + +/** + * vfio_ap_free_aqic_resources + * @q: The vfio_ap_queue + * + * Unregisters the ISC in the GIB when the saved ISC not invalid. + * Unpin the guest's page holding the NIB when it exist. + * Reset the saved_pfn and saved_isc to invalid values. + * + */ +static void vfio_ap_free_aqic_resources(struct vfio_ap_queue *q) +{ + if (!q) + return; + if (q->saved_isc != VFIO_AP_ISC_INVALID && + !WARN_ON(!(q->matrix_mdev && q->matrix_mdev->kvm))) { + kvm_s390_gisc_unregister(q->matrix_mdev->kvm, q->saved_isc); + q->saved_isc = VFIO_AP_ISC_INVALID; + } + if (q->saved_pfn && !WARN_ON(!q->matrix_mdev)) { + vfio_unpin_pages(mdev_dev(q->matrix_mdev->mdev), + &q->saved_pfn, 1); + q->saved_pfn = 0; + } +} + +/** + * vfio_ap_irq_disable + * @q: The vfio_ap_queue + * + * Uses ap_aqic to disable the interruption and in case of success, reset + * in progress or IRQ disable command already proceeded: calls + * vfio_ap_wait_for_irqclear() to check for the IRQ bit to be clear + * and calls vfio_ap_free_aqic_resources() to free the resources associated + * with the AP interrupt handling. + * + * In the case the AP is busy, or a reset is in progress, + * retries after 20ms, up to 5 times. + * + * Returns if ap_aqic function failed with invalid, deconfigured or + * checkstopped AP. + */ +static struct ap_queue_status vfio_ap_irq_disable(struct vfio_ap_queue *q) +{ + struct ap_qirq_ctrl aqic_gisa = {}; + struct ap_queue_status status; + int retries = 5; + + do { + status = ap_aqic(q->apqn, aqic_gisa, NULL); + switch (status.response_code) { + case AP_RESPONSE_OTHERWISE_CHANGED: + case AP_RESPONSE_NORMAL: + vfio_ap_wait_for_irqclear(q->apqn); + goto end_free; + case AP_RESPONSE_RESET_IN_PROGRESS: + case AP_RESPONSE_BUSY: + msleep(20); + break; + case AP_RESPONSE_Q_NOT_AVAIL: + case AP_RESPONSE_DECONFIGURED: + case AP_RESPONSE_CHECKSTOPPED: + case AP_RESPONSE_INVALID_ADDRESS: + default: + /* All cases in default means AP not operational */ + WARN_ONCE(1, "%s: ap_aqic status %d\n", __func__, + status.response_code); + goto end_free; + } + } while (retries--); + + WARN_ONCE(1, "%s: ap_aqic status %d\n", __func__, + status.response_code); +end_free: + vfio_ap_free_aqic_resources(q); + q->matrix_mdev = NULL; + return status; +} + +/** + * vfio_ap_setirq: Enable Interruption for a APQN + * + * @dev: the device associated with the ap_queue + * @q: the vfio_ap_queue holding AQIC parameters + * + * Pin the NIB saved in *q + * Register the guest ISC to GIB interface and retrieve the + * host ISC to issue the host side PQAP/AQIC + * + * Response.status may be set to AP_RESPONSE_INVALID_ADDRESS in case the + * vfio_pin_pages failed. + * + * Otherwise return the ap_queue_status returned by the ap_aqic(), + * all retry handling will be done by the guest. + */ +static struct ap_queue_status vfio_ap_irq_enable(struct vfio_ap_queue *q, + int isc, + unsigned long nib) +{ + struct ap_qirq_ctrl aqic_gisa = {}; + struct ap_queue_status status = {}; + struct kvm_s390_gisa *gisa; + struct kvm *kvm; + unsigned long h_nib, g_pfn, h_pfn; + int ret; + + g_pfn = nib >> PAGE_SHIFT; + ret = vfio_pin_pages(mdev_dev(q->matrix_mdev->mdev), &g_pfn, 1, + IOMMU_READ | IOMMU_WRITE, &h_pfn); + switch (ret) { + case 1: + break; + default: + status.response_code = AP_RESPONSE_INVALID_ADDRESS; + return status; + } + + kvm = q->matrix_mdev->kvm; + gisa = kvm->arch.gisa_int.origin; + + h_nib = (h_pfn << PAGE_SHIFT) | (nib & ~PAGE_MASK); + aqic_gisa.gisc = isc; + aqic_gisa.isc = kvm_s390_gisc_register(kvm, isc); + aqic_gisa.ir = 1; + aqic_gisa.gisa = (uint64_t)gisa >> 4; + + status = ap_aqic(q->apqn, aqic_gisa, (void *)h_nib); + switch (status.response_code) { + case AP_RESPONSE_NORMAL: + /* See if we did clear older IRQ configuration */ + vfio_ap_free_aqic_resources(q); + q->saved_pfn = g_pfn; + q->saved_isc = isc; + break; + case AP_RESPONSE_OTHERWISE_CHANGED: + /* We could not modify IRQ setings: clear new configuration */ + vfio_unpin_pages(mdev_dev(q->matrix_mdev->mdev), &g_pfn, 1); + kvm_s390_gisc_unregister(kvm, isc); + break; + default: + pr_warn("%s: apqn %04x: response: %02x\n", __func__, q->apqn, + status.response_code); + vfio_ap_irq_disable(q); + break; + } + + return status; +} + +/** + * handle_pqap: PQAP instruction callback + * + * @vcpu: The vcpu on which we received the PQAP instruction + * + * Get the general register contents to initialize internal variables. + * REG[0]: APQN + * REG[1]: IR and ISC + * REG[2]: NIB + * + * Response.status may be set to following Response Code: + * - AP_RESPONSE_Q_NOT_AVAIL: if the queue is not available + * - AP_RESPONSE_DECONFIGURED: if the queue is not configured + * - AP_RESPONSE_NORMAL (0) : in case of successs + * Check vfio_ap_setirq() and vfio_ap_clrirq() for other possible RC. + * We take the matrix_dev lock to ensure serialization on queues and + * mediated device access. + * + * Return 0 if we could handle the request inside KVM. + * otherwise, returns -EOPNOTSUPP to let QEMU handle the fault. + */ +static int handle_pqap(struct kvm_vcpu *vcpu) +{ + uint64_t status; + uint16_t apqn; + struct vfio_ap_queue *q; + struct ap_queue_status qstatus = { + .response_code = AP_RESPONSE_Q_NOT_AVAIL, }; + struct ap_matrix_mdev *matrix_mdev; + + /* If we do not use the AIV facility just go to userland */ + if (!(vcpu->arch.sie_block->eca & ECA_AIV)) + return -EOPNOTSUPP; + + apqn = vcpu->run->s.regs.gprs[0] & 0xffff; + mutex_lock(&matrix_dev->lock); + + if (!vcpu->kvm->arch.crypto.pqap_hook) + goto out_unlock; + matrix_mdev = container_of(vcpu->kvm->arch.crypto.pqap_hook, + struct ap_matrix_mdev, pqap_hook); + + q = vfio_ap_get_queue(matrix_mdev, apqn); + if (!q) + goto out_unlock; + + status = vcpu->run->s.regs.gprs[1]; + + /* If IR bit(16) is set we enable the interrupt */ + if ((status >> (63 - 16)) & 0x01) + qstatus = vfio_ap_irq_enable(q, status & 0x07, + vcpu->run->s.regs.gprs[2]); + else + qstatus = vfio_ap_irq_disable(q); + +out_unlock: + memcpy(&vcpu->run->s.regs.gprs[1], &qstatus, sizeof(qstatus)); + vcpu->run->s.regs.gprs[1] >>= 32; + mutex_unlock(&matrix_dev->lock); + return 0; +} + +static void vfio_ap_matrix_init(struct ap_config_info *info, + struct ap_matrix *matrix) +{ + matrix->apm_max = info->apxa ? info->Na : 63; + matrix->aqm_max = info->apxa ? info->Nd : 15; + matrix->adm_max = info->apxa ? info->Nd : 15; +} + +static int vfio_ap_mdev_create(struct kobject *kobj, struct mdev_device *mdev) +{ + struct ap_matrix_mdev *matrix_mdev; + + if ((atomic_dec_if_positive(&matrix_dev->available_instances) < 0)) + return -EPERM; + + matrix_mdev = kzalloc(sizeof(*matrix_mdev), GFP_KERNEL); + if (!matrix_mdev) { + atomic_inc(&matrix_dev->available_instances); + return -ENOMEM; + } + + matrix_mdev->mdev = mdev; + vfio_ap_matrix_init(&matrix_dev->info, &matrix_mdev->matrix); + mdev_set_drvdata(mdev, matrix_mdev); + matrix_mdev->pqap_hook.hook = handle_pqap; + matrix_mdev->pqap_hook.owner = THIS_MODULE; + mutex_lock(&matrix_dev->lock); + list_add(&matrix_mdev->node, &matrix_dev->mdev_list); + mutex_unlock(&matrix_dev->lock); + + return 0; +} + +static int vfio_ap_mdev_remove(struct mdev_device *mdev) +{ + struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); + + if (matrix_mdev->kvm) + return -EBUSY; + + mutex_lock(&matrix_dev->lock); + vfio_ap_mdev_reset_queues(mdev); + list_del(&matrix_mdev->node); + mutex_unlock(&matrix_dev->lock); + + kfree(matrix_mdev); + mdev_set_drvdata(mdev, NULL); + atomic_inc(&matrix_dev->available_instances); + + return 0; +} + +static ssize_t name_show(struct kobject *kobj, struct device *dev, char *buf) +{ + return sprintf(buf, "%s\n", VFIO_AP_MDEV_NAME_HWVIRT); +} + +static MDEV_TYPE_ATTR_RO(name); + +static ssize_t available_instances_show(struct kobject *kobj, + struct device *dev, char *buf) +{ + return sprintf(buf, "%d\n", + atomic_read(&matrix_dev->available_instances)); +} + +static MDEV_TYPE_ATTR_RO(available_instances); + +static ssize_t device_api_show(struct kobject *kobj, struct device *dev, + char *buf) +{ + return sprintf(buf, "%s\n", VFIO_DEVICE_API_AP_STRING); +} + +static MDEV_TYPE_ATTR_RO(device_api); + +static struct attribute *vfio_ap_mdev_type_attrs[] = { + &mdev_type_attr_name.attr, + &mdev_type_attr_device_api.attr, + &mdev_type_attr_available_instances.attr, + NULL, +}; + +static struct attribute_group vfio_ap_mdev_hwvirt_type_group = { + .name = VFIO_AP_MDEV_TYPE_HWVIRT, + .attrs = vfio_ap_mdev_type_attrs, +}; + +static struct attribute_group *vfio_ap_mdev_type_groups[] = { + &vfio_ap_mdev_hwvirt_type_group, + NULL, +}; + +struct vfio_ap_queue_reserved { + unsigned long *apid; + unsigned long *apqi; + bool reserved; +}; + +/** + * vfio_ap_has_queue + * + * @dev: an AP queue device + * @data: a struct vfio_ap_queue_reserved reference + * + * Flags whether the AP queue device (@dev) has a queue ID containing the APQN, + * apid or apqi specified in @data: + * + * - If @data contains both an apid and apqi value, then @data will be flagged + * as reserved if the APID and APQI fields for the AP queue device matches + * + * - If @data contains only an apid value, @data will be flagged as + * reserved if the APID field in the AP queue device matches + * + * - If @data contains only an apqi value, @data will be flagged as + * reserved if the APQI field in the AP queue device matches + * + * Returns 0 to indicate the input to function succeeded. Returns -EINVAL if + * @data does not contain either an apid or apqi. + */ +static int vfio_ap_has_queue(struct device *dev, void *data) +{ + struct vfio_ap_queue_reserved *qres = data; + struct ap_queue *ap_queue = to_ap_queue(dev); + ap_qid_t qid; + unsigned long id; + + if (qres->apid && qres->apqi) { + qid = AP_MKQID(*qres->apid, *qres->apqi); + if (qid == ap_queue->qid) + qres->reserved = true; + } else if (qres->apid && !qres->apqi) { + id = AP_QID_CARD(ap_queue->qid); + if (id == *qres->apid) + qres->reserved = true; + } else if (!qres->apid && qres->apqi) { + id = AP_QID_QUEUE(ap_queue->qid); + if (id == *qres->apqi) + qres->reserved = true; + } else { + return -EINVAL; + } + + return 0; +} + +/** + * vfio_ap_verify_queue_reserved + * + * @matrix_dev: a mediated matrix device + * @apid: an AP adapter ID + * @apqi: an AP queue index + * + * Verifies that the AP queue with @apid/@apqi is reserved by the VFIO AP device + * driver according to the following rules: + * + * - If both @apid and @apqi are not NULL, then there must be an AP queue + * device bound to the vfio_ap driver with the APQN identified by @apid and + * @apqi + * + * - If only @apid is not NULL, then there must be an AP queue device bound + * to the vfio_ap driver with an APQN containing @apid + * + * - If only @apqi is not NULL, then there must be an AP queue device bound + * to the vfio_ap driver with an APQN containing @apqi + * + * Returns 0 if the AP queue is reserved; otherwise, returns -EADDRNOTAVAIL. + */ +static int vfio_ap_verify_queue_reserved(unsigned long *apid, + unsigned long *apqi) +{ + int ret; + struct vfio_ap_queue_reserved qres; + + qres.apid = apid; + qres.apqi = apqi; + qres.reserved = false; + + ret = driver_for_each_device(&matrix_dev->vfio_ap_drv->driver, NULL, + &qres, vfio_ap_has_queue); + if (ret) + return ret; + + if (qres.reserved) + return 0; + + return -EADDRNOTAVAIL; +} + +static int +vfio_ap_mdev_verify_queues_reserved_for_apid(struct ap_matrix_mdev *matrix_mdev, + unsigned long apid) +{ + int ret; + unsigned long apqi; + unsigned long nbits = matrix_mdev->matrix.aqm_max + 1; + + if (find_first_bit_inv(matrix_mdev->matrix.aqm, nbits) >= nbits) + return vfio_ap_verify_queue_reserved(&apid, NULL); + + for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, nbits) { + ret = vfio_ap_verify_queue_reserved(&apid, &apqi); + if (ret) + return ret; + } + + return 0; +} + +/** + * vfio_ap_mdev_verify_no_sharing + * + * Verifies that the APQNs derived from the cross product of the AP adapter IDs + * and AP queue indexes comprising the AP matrix are not configured for another + * mediated device. AP queue sharing is not allowed. + * + * @matrix_mdev: the mediated matrix device + * + * Returns 0 if the APQNs are not shared, otherwise; returns -EADDRINUSE. + */ +static int vfio_ap_mdev_verify_no_sharing(struct ap_matrix_mdev *matrix_mdev) +{ + struct ap_matrix_mdev *lstdev; + DECLARE_BITMAP(apm, AP_DEVICES); + DECLARE_BITMAP(aqm, AP_DOMAINS); + + list_for_each_entry(lstdev, &matrix_dev->mdev_list, node) { + if (matrix_mdev == lstdev) + continue; + + memset(apm, 0, sizeof(apm)); + memset(aqm, 0, sizeof(aqm)); + + /* + * We work on full longs, as we can only exclude the leftover + * bits in non-inverse order. The leftover is all zeros. + */ + if (!bitmap_and(apm, matrix_mdev->matrix.apm, + lstdev->matrix.apm, AP_DEVICES)) + continue; + + if (!bitmap_and(aqm, matrix_mdev->matrix.aqm, + lstdev->matrix.aqm, AP_DOMAINS)) + continue; + + return -EADDRINUSE; + } + + return 0; +} + +/** + * assign_adapter_store + * + * @dev: the matrix device + * @attr: the mediated matrix device's assign_adapter attribute + * @buf: a buffer containing the AP adapter number (APID) to + * be assigned + * @count: the number of bytes in @buf + * + * Parses the APID from @buf and sets the corresponding bit in the mediated + * matrix device's APM. + * + * Returns the number of bytes processed if the APID is valid; otherwise, + * returns one of the following errors: + * + * 1. -EINVAL + * The APID is not a valid number + * + * 2. -ENODEV + * The APID exceeds the maximum value configured for the system + * + * 3. -EADDRNOTAVAIL + * An APQN derived from the cross product of the APID being assigned + * and the APQIs previously assigned is not bound to the vfio_ap device + * driver; or, if no APQIs have yet been assigned, the APID is not + * contained in an APQN bound to the vfio_ap device driver. + * + * 4. -EADDRINUSE + * An APQN derived from the cross product of the APID being assigned + * and the APQIs previously assigned is being used by another mediated + * matrix device + */ +static ssize_t assign_adapter_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + int ret; + unsigned long apid; + struct mdev_device *mdev = mdev_from_dev(dev); + struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); + + /* If the guest is running, disallow assignment of adapter */ + if (matrix_mdev->kvm) + return -EBUSY; + + ret = kstrtoul(buf, 0, &apid); + if (ret) + return ret; + + if (apid > matrix_mdev->matrix.apm_max) + return -ENODEV; + + /* + * Set the bit in the AP mask (APM) corresponding to the AP adapter + * number (APID). The bits in the mask, from most significant to least + * significant bit, correspond to APIDs 0-255. + */ + mutex_lock(&matrix_dev->lock); + + ret = vfio_ap_mdev_verify_queues_reserved_for_apid(matrix_mdev, apid); + if (ret) + goto done; + + set_bit_inv(apid, matrix_mdev->matrix.apm); + + ret = vfio_ap_mdev_verify_no_sharing(matrix_mdev); + if (ret) + goto share_err; + + ret = count; + goto done; + +share_err: + clear_bit_inv(apid, matrix_mdev->matrix.apm); +done: + mutex_unlock(&matrix_dev->lock); + + return ret; +} +static DEVICE_ATTR_WO(assign_adapter); + +/** + * unassign_adapter_store + * + * @dev: the matrix device + * @attr: the mediated matrix device's unassign_adapter attribute + * @buf: a buffer containing the adapter number (APID) to be unassigned + * @count: the number of bytes in @buf + * + * Parses the APID from @buf and clears the corresponding bit in the mediated + * matrix device's APM. + * + * Returns the number of bytes processed if the APID is valid; otherwise, + * returns one of the following errors: + * -EINVAL if the APID is not a number + * -ENODEV if the APID it exceeds the maximum value configured for the + * system + */ +static ssize_t unassign_adapter_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + int ret; + unsigned long apid; + struct mdev_device *mdev = mdev_from_dev(dev); + struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); + + /* If the guest is running, disallow un-assignment of adapter */ + if (matrix_mdev->kvm) + return -EBUSY; + + ret = kstrtoul(buf, 0, &apid); + if (ret) + return ret; + + if (apid > matrix_mdev->matrix.apm_max) + return -ENODEV; + + mutex_lock(&matrix_dev->lock); + clear_bit_inv((unsigned long)apid, matrix_mdev->matrix.apm); + mutex_unlock(&matrix_dev->lock); + + return count; +} +static DEVICE_ATTR_WO(unassign_adapter); + +static int +vfio_ap_mdev_verify_queues_reserved_for_apqi(struct ap_matrix_mdev *matrix_mdev, + unsigned long apqi) +{ + int ret; + unsigned long apid; + unsigned long nbits = matrix_mdev->matrix.apm_max + 1; + + if (find_first_bit_inv(matrix_mdev->matrix.apm, nbits) >= nbits) + return vfio_ap_verify_queue_reserved(NULL, &apqi); + + for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, nbits) { + ret = vfio_ap_verify_queue_reserved(&apid, &apqi); + if (ret) + return ret; + } + + return 0; +} + +/** + * assign_domain_store + * + * @dev: the matrix device + * @attr: the mediated matrix device's assign_domain attribute + * @buf: a buffer containing the AP queue index (APQI) of the domain to + * be assigned + * @count: the number of bytes in @buf + * + * Parses the APQI from @buf and sets the corresponding bit in the mediated + * matrix device's AQM. + * + * Returns the number of bytes processed if the APQI is valid; otherwise returns + * one of the following errors: + * + * 1. -EINVAL + * The APQI is not a valid number + * + * 2. -ENODEV + * The APQI exceeds the maximum value configured for the system + * + * 3. -EADDRNOTAVAIL + * An APQN derived from the cross product of the APQI being assigned + * and the APIDs previously assigned is not bound to the vfio_ap device + * driver; or, if no APIDs have yet been assigned, the APQI is not + * contained in an APQN bound to the vfio_ap device driver. + * + * 4. -EADDRINUSE + * An APQN derived from the cross product of the APQI being assigned + * and the APIDs previously assigned is being used by another mediated + * matrix device + */ +static ssize_t assign_domain_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + int ret; + unsigned long apqi; + struct mdev_device *mdev = mdev_from_dev(dev); + struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); + unsigned long max_apqi = matrix_mdev->matrix.aqm_max; + + /* If the guest is running, disallow assignment of domain */ + if (matrix_mdev->kvm) + return -EBUSY; + + ret = kstrtoul(buf, 0, &apqi); + if (ret) + return ret; + if (apqi > max_apqi) + return -ENODEV; + + mutex_lock(&matrix_dev->lock); + + ret = vfio_ap_mdev_verify_queues_reserved_for_apqi(matrix_mdev, apqi); + if (ret) + goto done; + + set_bit_inv(apqi, matrix_mdev->matrix.aqm); + + ret = vfio_ap_mdev_verify_no_sharing(matrix_mdev); + if (ret) + goto share_err; + + ret = count; + goto done; + +share_err: + clear_bit_inv(apqi, matrix_mdev->matrix.aqm); +done: + mutex_unlock(&matrix_dev->lock); + + return ret; +} +static DEVICE_ATTR_WO(assign_domain); + + +/** + * unassign_domain_store + * + * @dev: the matrix device + * @attr: the mediated matrix device's unassign_domain attribute + * @buf: a buffer containing the AP queue index (APQI) of the domain to + * be unassigned + * @count: the number of bytes in @buf + * + * Parses the APQI from @buf and clears the corresponding bit in the + * mediated matrix device's AQM. + * + * Returns the number of bytes processed if the APQI is valid; otherwise, + * returns one of the following errors: + * -EINVAL if the APQI is not a number + * -ENODEV if the APQI exceeds the maximum value configured for the system + */ +static ssize_t unassign_domain_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + int ret; + unsigned long apqi; + struct mdev_device *mdev = mdev_from_dev(dev); + struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); + + /* If the guest is running, disallow un-assignment of domain */ + if (matrix_mdev->kvm) + return -EBUSY; + + ret = kstrtoul(buf, 0, &apqi); + if (ret) + return ret; + + if (apqi > matrix_mdev->matrix.aqm_max) + return -ENODEV; + + mutex_lock(&matrix_dev->lock); + clear_bit_inv((unsigned long)apqi, matrix_mdev->matrix.aqm); + mutex_unlock(&matrix_dev->lock); + + return count; +} +static DEVICE_ATTR_WO(unassign_domain); + +/** + * assign_control_domain_store + * + * @dev: the matrix device + * @attr: the mediated matrix device's assign_control_domain attribute + * @buf: a buffer containing the domain ID to be assigned + * @count: the number of bytes in @buf + * + * Parses the domain ID from @buf and sets the corresponding bit in the mediated + * matrix device's ADM. + * + * Returns the number of bytes processed if the domain ID is valid; otherwise, + * returns one of the following errors: + * -EINVAL if the ID is not a number + * -ENODEV if the ID exceeds the maximum value configured for the system + */ +static ssize_t assign_control_domain_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + int ret; + unsigned long id; + struct mdev_device *mdev = mdev_from_dev(dev); + struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); + + /* If the guest is running, disallow assignment of control domain */ + if (matrix_mdev->kvm) + return -EBUSY; + + ret = kstrtoul(buf, 0, &id); + if (ret) + return ret; + + if (id > matrix_mdev->matrix.adm_max) + return -ENODEV; + + /* Set the bit in the ADM (bitmask) corresponding to the AP control + * domain number (id). The bits in the mask, from most significant to + * least significant, correspond to IDs 0 up to the one less than the + * number of control domains that can be assigned. + */ + mutex_lock(&matrix_dev->lock); + set_bit_inv(id, matrix_mdev->matrix.adm); + mutex_unlock(&matrix_dev->lock); + + return count; +} +static DEVICE_ATTR_WO(assign_control_domain); + +/** + * unassign_control_domain_store + * + * @dev: the matrix device + * @attr: the mediated matrix device's unassign_control_domain attribute + * @buf: a buffer containing the domain ID to be unassigned + * @count: the number of bytes in @buf + * + * Parses the domain ID from @buf and clears the corresponding bit in the + * mediated matrix device's ADM. + * + * Returns the number of bytes processed if the domain ID is valid; otherwise, + * returns one of the following errors: + * -EINVAL if the ID is not a number + * -ENODEV if the ID exceeds the maximum value configured for the system + */ +static ssize_t unassign_control_domain_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + int ret; + unsigned long domid; + struct mdev_device *mdev = mdev_from_dev(dev); + struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); + unsigned long max_domid = matrix_mdev->matrix.adm_max; + + /* If the guest is running, disallow un-assignment of control domain */ + if (matrix_mdev->kvm) + return -EBUSY; + + ret = kstrtoul(buf, 0, &domid); + if (ret) + return ret; + if (domid > max_domid) + return -ENODEV; + + mutex_lock(&matrix_dev->lock); + clear_bit_inv(domid, matrix_mdev->matrix.adm); + mutex_unlock(&matrix_dev->lock); + + return count; +} +static DEVICE_ATTR_WO(unassign_control_domain); + +static ssize_t control_domains_show(struct device *dev, + struct device_attribute *dev_attr, + char *buf) +{ + unsigned long id; + int nchars = 0; + int n; + char *bufpos = buf; + struct mdev_device *mdev = mdev_from_dev(dev); + struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); + unsigned long max_domid = matrix_mdev->matrix.adm_max; + + mutex_lock(&matrix_dev->lock); + for_each_set_bit_inv(id, matrix_mdev->matrix.adm, max_domid + 1) { + n = sprintf(bufpos, "%04lx\n", id); + bufpos += n; + nchars += n; + } + mutex_unlock(&matrix_dev->lock); + + return nchars; +} +static DEVICE_ATTR_RO(control_domains); + +static ssize_t matrix_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct mdev_device *mdev = mdev_from_dev(dev); + struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); + char *bufpos = buf; + unsigned long apid; + unsigned long apqi; + unsigned long apid1; + unsigned long apqi1; + unsigned long napm_bits = matrix_mdev->matrix.apm_max + 1; + unsigned long naqm_bits = matrix_mdev->matrix.aqm_max + 1; + int nchars = 0; + int n; + + apid1 = find_first_bit_inv(matrix_mdev->matrix.apm, napm_bits); + apqi1 = find_first_bit_inv(matrix_mdev->matrix.aqm, naqm_bits); + + mutex_lock(&matrix_dev->lock); + + if ((apid1 < napm_bits) && (apqi1 < naqm_bits)) { + for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, napm_bits) { + for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, + naqm_bits) { + n = sprintf(bufpos, "%02lx.%04lx\n", apid, + apqi); + bufpos += n; + nchars += n; + } + } + } else if (apid1 < napm_bits) { + for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, napm_bits) { + n = sprintf(bufpos, "%02lx.\n", apid); + bufpos += n; + nchars += n; + } + } else if (apqi1 < naqm_bits) { + for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, naqm_bits) { + n = sprintf(bufpos, ".%04lx\n", apqi); + bufpos += n; + nchars += n; + } + } + + mutex_unlock(&matrix_dev->lock); + + return nchars; +} +static DEVICE_ATTR_RO(matrix); + +static struct attribute *vfio_ap_mdev_attrs[] = { + &dev_attr_assign_adapter.attr, + &dev_attr_unassign_adapter.attr, + &dev_attr_assign_domain.attr, + &dev_attr_unassign_domain.attr, + &dev_attr_assign_control_domain.attr, + &dev_attr_unassign_control_domain.attr, + &dev_attr_control_domains.attr, + &dev_attr_matrix.attr, + NULL, +}; + +static struct attribute_group vfio_ap_mdev_attr_group = { + .attrs = vfio_ap_mdev_attrs +}; + +static const struct attribute_group *vfio_ap_mdev_attr_groups[] = { + &vfio_ap_mdev_attr_group, + NULL +}; + +/** + * vfio_ap_mdev_set_kvm + * + * @matrix_mdev: a mediated matrix device + * @kvm: reference to KVM instance + * + * Verifies no other mediated matrix device has @kvm and sets a reference to + * it in @matrix_mdev->kvm. + * + * Return 0 if no other mediated matrix device has a reference to @kvm; + * otherwise, returns an -EPERM. + */ +static int vfio_ap_mdev_set_kvm(struct ap_matrix_mdev *matrix_mdev, + struct kvm *kvm) +{ + struct ap_matrix_mdev *m; + + mutex_lock(&matrix_dev->lock); + + list_for_each_entry(m, &matrix_dev->mdev_list, node) { + if ((m != matrix_mdev) && (m->kvm == kvm)) { + mutex_unlock(&matrix_dev->lock); + return -EPERM; + } + } + + matrix_mdev->kvm = kvm; + kvm_get_kvm(kvm); + kvm->arch.crypto.pqap_hook = &matrix_mdev->pqap_hook; + mutex_unlock(&matrix_dev->lock); + + return 0; +} + +/* + * vfio_ap_mdev_iommu_notifier: IOMMU notifier callback + * + * @nb: The notifier block + * @action: Action to be taken + * @data: data associated with the request + * + * For an UNMAP request, unpin the guest IOVA (the NIB guest address we + * pinned before). Other requests are ignored. + * + */ +static int vfio_ap_mdev_iommu_notifier(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct ap_matrix_mdev *matrix_mdev; + + matrix_mdev = container_of(nb, struct ap_matrix_mdev, iommu_notifier); + + if (action == VFIO_IOMMU_NOTIFY_DMA_UNMAP) { + struct vfio_iommu_type1_dma_unmap *unmap = data; + unsigned long g_pfn = unmap->iova >> PAGE_SHIFT; + + vfio_unpin_pages(mdev_dev(matrix_mdev->mdev), &g_pfn, 1); + return NOTIFY_OK; + } + + return NOTIFY_DONE; +} + +static int vfio_ap_mdev_group_notifier(struct notifier_block *nb, + unsigned long action, void *data) +{ + int ret; + struct ap_matrix_mdev *matrix_mdev; + + if (action != VFIO_GROUP_NOTIFY_SET_KVM) + return NOTIFY_OK; + + matrix_mdev = container_of(nb, struct ap_matrix_mdev, group_notifier); + + if (!data) { + matrix_mdev->kvm = NULL; + return NOTIFY_OK; + } + + ret = vfio_ap_mdev_set_kvm(matrix_mdev, data); + if (ret) + return NOTIFY_DONE; + + /* If there is no CRYCB pointer, then we can't copy the masks */ + if (!matrix_mdev->kvm->arch.crypto.crycbd) + return NOTIFY_DONE; + + kvm_arch_crypto_set_masks(matrix_mdev->kvm, matrix_mdev->matrix.apm, + matrix_mdev->matrix.aqm, + matrix_mdev->matrix.adm); + + return NOTIFY_OK; +} + +static struct vfio_ap_queue *vfio_ap_find_queue(int apqn) +{ + struct device *dev; + struct vfio_ap_queue *q = NULL; + + dev = driver_find_device(&matrix_dev->vfio_ap_drv->driver, NULL, + &apqn, match_apqn); + if (dev) { + q = dev_get_drvdata(dev); + put_device(dev); + } + + return q; +} + +int vfio_ap_mdev_reset_queue(struct vfio_ap_queue *q, + unsigned int retry) +{ + struct ap_queue_status status; + int ret; + int retry2 = 2; + + if (!q) + return 0; + +retry_zapq: + status = ap_zapq(q->apqn); + switch (status.response_code) { + case AP_RESPONSE_NORMAL: + ret = 0; + break; + case AP_RESPONSE_RESET_IN_PROGRESS: + if (retry--) { + msleep(20); + goto retry_zapq; + } + ret = -EBUSY; + break; + case AP_RESPONSE_Q_NOT_AVAIL: + case AP_RESPONSE_DECONFIGURED: + case AP_RESPONSE_CHECKSTOPPED: + WARN_ON_ONCE(status.irq_enabled); + ret = -EBUSY; + goto free_resources; + default: + /* things are really broken, give up */ + WARN(true, "PQAP/ZAPQ completed with invalid rc (%x)\n", + status.response_code); + return -EIO; + } + + /* wait for the reset to take effect */ + while (retry2--) { + if (status.queue_empty && !status.irq_enabled) + break; + msleep(20); + status = ap_tapq(q->apqn, NULL); + } + WARN_ON_ONCE(retry2 <= 0); + +free_resources: + vfio_ap_free_aqic_resources(q); + + return ret; +} + +static int vfio_ap_mdev_reset_queues(struct mdev_device *mdev) +{ + int ret; + int rc = 0; + unsigned long apid, apqi; + struct vfio_ap_queue *q; + struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); + + for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, + matrix_mdev->matrix.apm_max + 1) { + for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, + matrix_mdev->matrix.aqm_max + 1) { + q = vfio_ap_find_queue(AP_MKQID(apid, apqi)); + ret = vfio_ap_mdev_reset_queue(q, 1); + /* + * Regardless whether a queue turns out to be busy, or + * is not operational, we need to continue resetting + * the remaining queues. + */ + if (ret) + rc = ret; + } + } + + return rc; +} + +static int vfio_ap_mdev_open(struct mdev_device *mdev) +{ + struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); + unsigned long events; + int ret; + + + if (!try_module_get(THIS_MODULE)) + return -ENODEV; + + matrix_mdev->group_notifier.notifier_call = vfio_ap_mdev_group_notifier; + events = VFIO_GROUP_NOTIFY_SET_KVM; + + ret = vfio_register_notifier(mdev_dev(mdev), VFIO_GROUP_NOTIFY, + &events, &matrix_mdev->group_notifier); + if (ret) { + module_put(THIS_MODULE); + return ret; + } + + matrix_mdev->iommu_notifier.notifier_call = vfio_ap_mdev_iommu_notifier; + events = VFIO_IOMMU_NOTIFY_DMA_UNMAP; + ret = vfio_register_notifier(mdev_dev(mdev), VFIO_IOMMU_NOTIFY, + &events, &matrix_mdev->iommu_notifier); + if (!ret) + return ret; + + vfio_unregister_notifier(mdev_dev(mdev), VFIO_GROUP_NOTIFY, + &matrix_mdev->group_notifier); + module_put(THIS_MODULE); + return ret; +} + +static void vfio_ap_mdev_release(struct mdev_device *mdev) +{ + struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); + + mutex_lock(&matrix_dev->lock); + if (matrix_mdev->kvm) { + kvm_arch_crypto_clear_masks(matrix_mdev->kvm); + matrix_mdev->kvm->arch.crypto.pqap_hook = NULL; + vfio_ap_mdev_reset_queues(mdev); + kvm_put_kvm(matrix_mdev->kvm); + matrix_mdev->kvm = NULL; + } + mutex_unlock(&matrix_dev->lock); + + vfio_unregister_notifier(mdev_dev(mdev), VFIO_IOMMU_NOTIFY, + &matrix_mdev->iommu_notifier); + vfio_unregister_notifier(mdev_dev(mdev), VFIO_GROUP_NOTIFY, + &matrix_mdev->group_notifier); + module_put(THIS_MODULE); +} + +static int vfio_ap_mdev_get_device_info(unsigned long arg) +{ + unsigned long minsz; + struct vfio_device_info info; + + minsz = offsetofend(struct vfio_device_info, num_irqs); + + if (copy_from_user(&info, (void __user *)arg, minsz)) + return -EFAULT; + + if (info.argsz < minsz) + return -EINVAL; + + info.flags = VFIO_DEVICE_FLAGS_AP | VFIO_DEVICE_FLAGS_RESET; + info.num_regions = 0; + info.num_irqs = 0; + + return copy_to_user((void __user *)arg, &info, minsz) ? -EFAULT : 0; +} + +static ssize_t vfio_ap_mdev_ioctl(struct mdev_device *mdev, + unsigned int cmd, unsigned long arg) +{ + int ret; + + mutex_lock(&matrix_dev->lock); + switch (cmd) { + case VFIO_DEVICE_GET_INFO: + ret = vfio_ap_mdev_get_device_info(arg); + break; + case VFIO_DEVICE_RESET: + ret = vfio_ap_mdev_reset_queues(mdev); + break; + default: + ret = -EOPNOTSUPP; + break; + } + mutex_unlock(&matrix_dev->lock); + + return ret; +} + +static const struct mdev_parent_ops vfio_ap_matrix_ops = { + .owner = THIS_MODULE, + .supported_type_groups = vfio_ap_mdev_type_groups, + .mdev_attr_groups = vfio_ap_mdev_attr_groups, + .create = vfio_ap_mdev_create, + .remove = vfio_ap_mdev_remove, + .open = vfio_ap_mdev_open, + .release = vfio_ap_mdev_release, + .ioctl = vfio_ap_mdev_ioctl, +}; + +int vfio_ap_mdev_register(void) +{ + atomic_set(&matrix_dev->available_instances, MAX_ZDEV_ENTRIES_EXT); + + return mdev_register_device(&matrix_dev->device, &vfio_ap_matrix_ops); +} + +void vfio_ap_mdev_unregister(void) +{ + mdev_unregister_device(&matrix_dev->device); +} |