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authorLinus Torvalds <torvalds@linux-foundation.org>2018-10-25 17:57:35 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2018-10-25 17:57:35 -0700
commit0d1e8b8d2bcd3150d51754d8d0fdbf44dc88b0d3 (patch)
tree2794cb2347daa76b00160a6ffb68663f4138dcc7 /drivers
parent83c4087ce468601501ecde4d0ec5b2abd5f57c31 (diff)
parent22a7cdcae6a4a3c8974899e62851d270956f58ce (diff)
downloadlinux-0d1e8b8d2bcd3150d51754d8d0fdbf44dc88b0d3.tar.bz2
Merge tag 'kvm-4.20-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Radim Krčmář: "ARM: - Improved guest IPA space support (32 to 52 bits) - RAS event delivery for 32bit - PMU fixes - Guest entry hardening - Various cleanups - Port of dirty_log_test selftest PPC: - Nested HV KVM support for radix guests on POWER9. The performance is much better than with PR KVM. Migration and arbitrary level of nesting is supported. - Disable nested HV-KVM on early POWER9 chips that need a particular hardware bug workaround - One VM per core mode to prevent potential data leaks - PCI pass-through optimization - merge ppc-kvm topic branch and kvm-ppc-fixes to get a better base s390: - Initial version of AP crypto virtualization via vfio-mdev - Improvement for vfio-ap - Set the host program identifier - Optimize page table locking x86: - Enable nested virtualization by default - Implement Hyper-V IPI hypercalls - Improve #PF and #DB handling - Allow guests to use Enlightened VMCS - Add migration selftests for VMCS and Enlightened VMCS - Allow coalesced PIO accesses - Add an option to perform nested VMCS host state consistency check through hardware - Automatic tuning of lapic_timer_advance_ns - Many fixes, minor improvements, and cleanups" * tag 'kvm-4.20-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (204 commits) KVM/nVMX: Do not validate that posted_intr_desc_addr is page aligned Revert "kvm: x86: optimize dr6 restore" KVM: PPC: Optimize clearing TCEs for sparse tables x86/kvm/nVMX: tweak shadow fields selftests/kvm: add missing executables to .gitignore KVM: arm64: Safety check PSTATE when entering guest and handle IL KVM: PPC: Book3S HV: Don't use streamlined entry path on early POWER9 chips arm/arm64: KVM: Enable 32 bits kvm vcpu events support arm/arm64: KVM: Rename function kvm_arch_dev_ioctl_check_extension() KVM: arm64: Fix caching of host MDCR_EL2 value KVM: VMX: enable nested virtualization by default KVM/x86: Use 32bit xor to clear registers in svm.c kvm: x86: Introduce KVM_CAP_EXCEPTION_PAYLOAD kvm: vmx: Defer setting of DR6 until #DB delivery kvm: x86: Defer setting of CR2 until #PF delivery kvm: x86: Add payload operands to kvm_multiple_exception kvm: x86: Add exception payload fields to kvm_vcpu_events kvm: x86: Add has_payload and payload to kvm_queued_exception KVM: Documentation: Fix omission in struct kvm_vcpu_events KVM: selftests: add Enlightened VMCS test ...
Diffstat (limited to 'drivers')
-rw-r--r--drivers/iommu/Kconfig8
-rw-r--r--drivers/s390/crypto/Makefile4
-rw-r--r--drivers/s390/crypto/vfio_ap_drv.c157
-rw-r--r--drivers/s390/crypto/vfio_ap_ops.c939
-rw-r--r--drivers/s390/crypto/vfio_ap_private.h88
-rw-r--r--drivers/vfio/vfio_iommu_spapr_tce.c23
6 files changed, 1217 insertions, 2 deletions
diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index c60395b7470f..83e6d993fca5 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -372,6 +372,14 @@ config S390_CCW_IOMMU
Enables bits of IOMMU API required by VFIO. The iommu_ops
is not implemented as it is not necessary for VFIO.
+config S390_AP_IOMMU
+ bool "S390 AP IOMMU Support"
+ depends on S390 && ZCRYPT
+ select IOMMU_API
+ help
+ Enables bits of IOMMU API required by VFIO. The iommu_ops
+ is not implemented as it is not necessary for VFIO.
+
config MTK_IOMMU
bool "MTK IOMMU Support"
depends on ARM || ARM64
diff --git a/drivers/s390/crypto/Makefile b/drivers/s390/crypto/Makefile
index fd5e215c66b7..6ccd93d0b1cb 100644
--- a/drivers/s390/crypto/Makefile
+++ b/drivers/s390/crypto/Makefile
@@ -15,3 +15,7 @@ obj-$(CONFIG_ZCRYPT) += zcrypt_cex2c.o zcrypt_cex2a.o zcrypt_cex4.o
# pkey kernel module
pkey-objs := pkey_api.o
obj-$(CONFIG_PKEY) += pkey.o
+
+# adjunct processor matrix
+vfio_ap-objs := vfio_ap_drv.o vfio_ap_ops.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 000000000000..7667b38728f0
--- /dev/null
+++ b/drivers/s390/crypto/vfio_ap_drv.c
@@ -0,0 +1,157 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * VFIO based AP device driver
+ *
+ * Copyright IBM Corp. 2018
+ *
+ * Author(s): Tony Krowiak <akrowiak@linux.ibm.com>
+ */
+
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/slab.h>
+#include <linux/string.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. 2018");
+MODULE_LICENSE("GPL v2");
+
+static struct ap_driver vfio_ap_drv;
+
+static struct device_type vfio_ap_dev_type = {
+ .name = VFIO_AP_DEV_TYPE_NAME,
+};
+
+struct ap_matrix_dev *matrix_dev;
+
+/* 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_queue_dev_remove(struct ap_device *apdev)
+{
+ /* Nothing to do yet */
+}
+
+static void vfio_ap_matrix_dev_release(struct device *dev)
+{
+ struct ap_matrix_dev *matrix_dev = dev_get_drvdata(dev);
+
+ kfree(matrix_dev);
+}
+
+static int vfio_ap_matrix_dev_create(void)
+{
+ int ret;
+ struct device *root_device;
+
+ root_device = root_device_register(VFIO_AP_ROOT_NAME);
+ if (IS_ERR(root_device))
+ return PTR_ERR(root_device);
+
+ matrix_dev = kzalloc(sizeof(*matrix_dev), GFP_KERNEL);
+ if (!matrix_dev) {
+ ret = -ENOMEM;
+ goto matrix_alloc_err;
+ }
+
+ /* Fill in config info via PQAP(QCI), if available */
+ if (test_facility(12)) {
+ ret = ap_qci(&matrix_dev->info);
+ if (ret)
+ goto matrix_alloc_err;
+ }
+
+ mutex_init(&matrix_dev->lock);
+ INIT_LIST_HEAD(&matrix_dev->mdev_list);
+
+ matrix_dev->device.type = &vfio_ap_dev_type;
+ dev_set_name(&matrix_dev->device, "%s", VFIO_AP_DEV_NAME);
+ matrix_dev->device.parent = root_device;
+ matrix_dev->device.release = vfio_ap_matrix_dev_release;
+ matrix_dev->device.driver = &vfio_ap_drv.driver;
+
+ ret = device_register(&matrix_dev->device);
+ if (ret)
+ goto matrix_reg_err;
+
+ return 0;
+
+matrix_reg_err:
+ put_device(&matrix_dev->device);
+matrix_alloc_err:
+ root_device_unregister(root_device);
+
+ return ret;
+}
+
+static void vfio_ap_matrix_dev_destroy(void)
+{
+ device_unregister(&matrix_dev->device);
+ root_device_unregister(matrix_dev->device.parent);
+}
+
+static int __init vfio_ap_init(void)
+{
+ int ret;
+
+ /* If there are no AP instructions, there is nothing to pass through. */
+ if (!ap_instructions_available())
+ return -ENODEV;
+
+ 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.remove = vfio_ap_queue_dev_remove;
+ 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();
+ return ret;
+ }
+
+ ret = vfio_ap_mdev_register();
+ if (ret) {
+ ap_driver_unregister(&vfio_ap_drv);
+ vfio_ap_matrix_dev_destroy();
+
+ return ret;
+ }
+
+ return 0;
+}
+
+static void __exit vfio_ap_exit(void)
+{
+ vfio_ap_mdev_unregister();
+ ap_driver_unregister(&vfio_ap_drv);
+ vfio_ap_matrix_dev_destroy();
+}
+
+module_init(vfio_ap_init);
+module_exit(vfio_ap_exit);
diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
new file mode 100644
index 000000000000..272ef427dcc0
--- /dev/null
+++ b/drivers/s390/crypto/vfio_ap_ops.c
@@ -0,0 +1,939 @@
+// 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 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;
+ }
+
+ vfio_ap_matrix_init(&matrix_dev->info, &matrix_mdev->matrix);
+ mdev_set_drvdata(mdev, matrix_mdev);
+ 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);
+ 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->device.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;
+ mutex_unlock(&matrix_dev->lock);
+
+ return 0;
+}
+
+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 int vfio_ap_mdev_reset_queue(unsigned int apid, unsigned int apqi,
+ unsigned int retry)
+{
+ struct ap_queue_status status;
+
+ do {
+ status = ap_zapq(AP_MKQID(apid, apqi));
+ switch (status.response_code) {
+ case AP_RESPONSE_NORMAL:
+ return 0;
+ case AP_RESPONSE_RESET_IN_PROGRESS:
+ case AP_RESPONSE_BUSY:
+ msleep(20);
+ break;
+ default:
+ /* things are really broken, give up */
+ return -EIO;
+ }
+ } while (retry--);
+
+ return -EBUSY;
+}
+
+static int vfio_ap_mdev_reset_queues(struct mdev_device *mdev)
+{
+ int ret;
+ int rc = 0;
+ unsigned long apid, apqi;
+ 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) {
+ ret = vfio_ap_mdev_reset_queue(apid, apqi, 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;
+ }
+
+ return 0;
+}
+
+static void vfio_ap_mdev_release(struct mdev_device *mdev)
+{
+ struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev);
+
+ if (matrix_mdev->kvm)
+ kvm_arch_crypto_clear_masks(matrix_mdev->kvm);
+
+ vfio_ap_mdev_reset_queues(mdev);
+ vfio_unregister_notifier(mdev_dev(mdev), VFIO_GROUP_NOTIFY,
+ &matrix_mdev->group_notifier);
+ matrix_mdev->kvm = NULL;
+ 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);
+}
+
+static ssize_t vfio_ap_mdev_ioctl(struct mdev_device *mdev,
+ unsigned int cmd, unsigned long arg)
+{
+ int ret;
+
+ 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;
+ }
+
+ 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);
+}
diff --git a/drivers/s390/crypto/vfio_ap_private.h b/drivers/s390/crypto/vfio_ap_private.h
new file mode 100644
index 000000000000..5675492233c7
--- /dev/null
+++ b/drivers/s390/crypto/vfio_ap_private.h
@@ -0,0 +1,88 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Private data and functions for adjunct processor VFIO matrix driver.
+ *
+ * Author(s): Tony Krowiak <akrowiak@linux.ibm.com>
+ * Halil Pasic <pasic@linux.ibm.com>
+ *
+ * Copyright IBM Corp. 2018
+ */
+
+#ifndef _VFIO_AP_PRIVATE_H_
+#define _VFIO_AP_PRIVATE_H_
+
+#include <linux/types.h>
+#include <linux/device.h>
+#include <linux/mdev.h>
+#include <linux/delay.h>
+#include <linux/mutex.h>
+
+#include "ap_bus.h"
+
+#define VFIO_AP_MODULE_NAME "vfio_ap"
+#define VFIO_AP_DRV_NAME "vfio_ap"
+
+/**
+ * ap_matrix_dev - the AP matrix device structure
+ * @device: generic device structure associated with the AP matrix device
+ * @available_instances: number of mediated matrix devices that can be created
+ * @info: the struct containing the output from the PQAP(QCI) instruction
+ * mdev_list: the list of mediated matrix devices created
+ * lock: mutex for locking the AP matrix device. This lock will be
+ * taken every time we fiddle with state managed by the vfio_ap
+ * driver, be it using @mdev_list or writing the state of a
+ * single ap_matrix_mdev device. It's quite coarse but we don't
+ * expect much contention.
+ */
+struct ap_matrix_dev {
+ struct device device;
+ atomic_t available_instances;
+ struct ap_config_info info;
+ struct list_head mdev_list;
+ struct mutex lock;
+};
+
+extern struct ap_matrix_dev *matrix_dev;
+
+/**
+ * The AP matrix is comprised of three bit masks identifying the adapters,
+ * queues (domains) and control domains that belong to an AP matrix. The bits i
+ * each mask, from least significant to most significant bit, correspond to IDs
+ * 0 to 255. When a bit is set, the corresponding ID belongs to the matrix.
+ *
+ * @apm_max: max adapter number in @apm
+ * @apm identifies the AP adapters in the matrix
+ * @aqm_max: max domain number in @aqm
+ * @aqm identifies the AP queues (domains) in the matrix
+ * @adm_max: max domain number in @adm
+ * @adm identifies the AP control domains in the matrix
+ */
+struct ap_matrix {
+ unsigned long apm_max;
+ DECLARE_BITMAP(apm, 256);
+ unsigned long aqm_max;
+ DECLARE_BITMAP(aqm, 256);
+ unsigned long adm_max;
+ DECLARE_BITMAP(adm, 256);
+};
+
+/**
+ * struct ap_matrix_mdev - the mediated matrix device structure
+ * @list: allows the ap_matrix_mdev struct to be added to a list
+ * @matrix: the adapters, usage domains and control domains assigned to the
+ * mediated matrix device.
+ * @group_notifier: notifier block used for specifying callback function for
+ * handling the VFIO_GROUP_NOTIFY_SET_KVM event
+ * @kvm: the struct holding guest's state
+ */
+struct ap_matrix_mdev {
+ struct list_head node;
+ struct ap_matrix matrix;
+ struct notifier_block group_notifier;
+ struct kvm *kvm;
+};
+
+extern int vfio_ap_mdev_register(void);
+extern void vfio_ap_mdev_unregister(void);
+
+#endif /* _VFIO_AP_PRIVATE_H_ */
diff --git a/drivers/vfio/vfio_iommu_spapr_tce.c b/drivers/vfio/vfio_iommu_spapr_tce.c
index 96721b154454..b30926e11d87 100644
--- a/drivers/vfio/vfio_iommu_spapr_tce.c
+++ b/drivers/vfio/vfio_iommu_spapr_tce.c
@@ -444,7 +444,7 @@ static void tce_iommu_unuse_page_v2(struct tce_container *container,
struct mm_iommu_table_group_mem_t *mem = NULL;
int ret;
unsigned long hpa = 0;
- __be64 *pua = IOMMU_TABLE_USERSPACE_ENTRY(tbl, entry);
+ __be64 *pua = IOMMU_TABLE_USERSPACE_ENTRY_RO(tbl, entry);
if (!pua)
return;
@@ -467,8 +467,27 @@ static int tce_iommu_clear(struct tce_container *container,
unsigned long oldhpa;
long ret;
enum dma_data_direction direction;
+ unsigned long lastentry = entry + pages;
+
+ for ( ; entry < lastentry; ++entry) {
+ if (tbl->it_indirect_levels && tbl->it_userspace) {
+ /*
+ * For multilevel tables, we can take a shortcut here
+ * and skip some TCEs as we know that the userspace
+ * addresses cache is a mirror of the real TCE table
+ * and if it is missing some indirect levels, then
+ * the hardware table does not have them allocated
+ * either and therefore does not require updating.
+ */
+ __be64 *pua = IOMMU_TABLE_USERSPACE_ENTRY_RO(tbl,
+ entry);
+ if (!pua) {
+ /* align to level_size which is power of two */
+ entry |= tbl->it_level_size - 1;
+ continue;
+ }
+ }
- for ( ; pages; --pages, ++entry) {
cond_resched();
direction = DMA_NONE;