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Diffstat (limited to 'drivers/s390/cio/vfio_ccw_ops.c')
-rw-r--r--drivers/s390/cio/vfio_ccw_ops.c603
1 files changed, 603 insertions, 0 deletions
diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c
new file mode 100644
index 000000000..6ae4d012d
--- /dev/null
+++ b/drivers/s390/cio/vfio_ccw_ops.c
@@ -0,0 +1,603 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Physical device callbacks for vfio_ccw
+ *
+ * Copyright IBM Corp. 2017
+ * Copyright Red Hat, Inc. 2019
+ *
+ * Author(s): Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
+ * Xiao Feng Ren <renxiaof@linux.vnet.ibm.com>
+ * Cornelia Huck <cohuck@redhat.com>
+ */
+
+#include <linux/vfio.h>
+#include <linux/nospec.h>
+#include <linux/slab.h>
+
+#include "vfio_ccw_private.h"
+
+static const struct vfio_device_ops vfio_ccw_dev_ops;
+
+static int vfio_ccw_mdev_reset(struct vfio_ccw_private *private)
+{
+ /*
+ * If the FSM state is seen as Not Operational after closing
+ * and re-opening the mdev, return an error.
+ */
+ vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_CLOSE);
+ vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_OPEN);
+ if (private->state == VFIO_CCW_STATE_NOT_OPER)
+ return -EINVAL;
+
+ return 0;
+}
+
+static void vfio_ccw_dma_unmap(struct vfio_device *vdev, u64 iova, u64 length)
+{
+ struct vfio_ccw_private *private =
+ container_of(vdev, struct vfio_ccw_private, vdev);
+
+ /* Drivers MUST unpin pages in response to an invalidation. */
+ if (!cp_iova_pinned(&private->cp, iova, length))
+ return;
+
+ vfio_ccw_mdev_reset(private);
+}
+
+static int vfio_ccw_mdev_init_dev(struct vfio_device *vdev)
+{
+ struct vfio_ccw_private *private =
+ container_of(vdev, struct vfio_ccw_private, vdev);
+
+ init_completion(&private->release_comp);
+ return 0;
+}
+
+static int vfio_ccw_mdev_probe(struct mdev_device *mdev)
+{
+ struct vfio_ccw_private *private = dev_get_drvdata(mdev->dev.parent);
+ int ret;
+
+ if (private->state == VFIO_CCW_STATE_NOT_OPER)
+ return -ENODEV;
+
+ ret = vfio_init_device(&private->vdev, &mdev->dev, &vfio_ccw_dev_ops);
+ if (ret)
+ return ret;
+
+ VFIO_CCW_MSG_EVENT(2, "sch %x.%x.%04x: create\n",
+ private->sch->schid.cssid,
+ private->sch->schid.ssid,
+ private->sch->schid.sch_no);
+
+ ret = vfio_register_emulated_iommu_dev(&private->vdev);
+ if (ret)
+ goto err_put_vdev;
+ dev_set_drvdata(&mdev->dev, private);
+ return 0;
+
+err_put_vdev:
+ vfio_put_device(&private->vdev);
+ return ret;
+}
+
+static void vfio_ccw_mdev_release_dev(struct vfio_device *vdev)
+{
+ struct vfio_ccw_private *private =
+ container_of(vdev, struct vfio_ccw_private, vdev);
+
+ /*
+ * We cannot free vfio_ccw_private here because it includes
+ * parent info which must be free'ed by css driver.
+ *
+ * Use a workaround by memset'ing the core device part and
+ * then notifying the remove path that all active references
+ * to this device have been released.
+ */
+ memset(vdev, 0, sizeof(*vdev));
+ complete(&private->release_comp);
+}
+
+static void vfio_ccw_mdev_remove(struct mdev_device *mdev)
+{
+ struct vfio_ccw_private *private = dev_get_drvdata(mdev->dev.parent);
+
+ VFIO_CCW_MSG_EVENT(2, "sch %x.%x.%04x: remove\n",
+ private->sch->schid.cssid,
+ private->sch->schid.ssid,
+ private->sch->schid.sch_no);
+
+ vfio_unregister_group_dev(&private->vdev);
+
+ vfio_put_device(&private->vdev);
+ /*
+ * Wait for all active references on mdev are released so it
+ * is safe to defer kfree() to a later point.
+ *
+ * TODO: the clean fix is to split parent/mdev info from ccw
+ * private structure so each can be managed in its own life
+ * cycle.
+ */
+ wait_for_completion(&private->release_comp);
+}
+
+static int vfio_ccw_mdev_open_device(struct vfio_device *vdev)
+{
+ struct vfio_ccw_private *private =
+ container_of(vdev, struct vfio_ccw_private, vdev);
+ int ret;
+
+ /* Device cannot simply be opened again from this state */
+ if (private->state == VFIO_CCW_STATE_NOT_OPER)
+ return -EINVAL;
+
+ ret = vfio_ccw_register_async_dev_regions(private);
+ if (ret)
+ return ret;
+
+ ret = vfio_ccw_register_schib_dev_regions(private);
+ if (ret)
+ goto out_unregister;
+
+ ret = vfio_ccw_register_crw_dev_regions(private);
+ if (ret)
+ goto out_unregister;
+
+ vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_OPEN);
+ if (private->state == VFIO_CCW_STATE_NOT_OPER) {
+ ret = -EINVAL;
+ goto out_unregister;
+ }
+
+ return ret;
+
+out_unregister:
+ vfio_ccw_unregister_dev_regions(private);
+ return ret;
+}
+
+static void vfio_ccw_mdev_close_device(struct vfio_device *vdev)
+{
+ struct vfio_ccw_private *private =
+ container_of(vdev, struct vfio_ccw_private, vdev);
+
+ vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_CLOSE);
+ vfio_ccw_unregister_dev_regions(private);
+}
+
+static ssize_t vfio_ccw_mdev_read_io_region(struct vfio_ccw_private *private,
+ char __user *buf, size_t count,
+ loff_t *ppos)
+{
+ loff_t pos = *ppos & VFIO_CCW_OFFSET_MASK;
+ struct ccw_io_region *region;
+ int ret;
+
+ if (pos + count > sizeof(*region))
+ return -EINVAL;
+
+ mutex_lock(&private->io_mutex);
+ region = private->io_region;
+ if (copy_to_user(buf, (void *)region + pos, count))
+ ret = -EFAULT;
+ else
+ ret = count;
+ mutex_unlock(&private->io_mutex);
+ return ret;
+}
+
+static ssize_t vfio_ccw_mdev_read(struct vfio_device *vdev,
+ char __user *buf,
+ size_t count,
+ loff_t *ppos)
+{
+ struct vfio_ccw_private *private =
+ container_of(vdev, struct vfio_ccw_private, vdev);
+ unsigned int index = VFIO_CCW_OFFSET_TO_INDEX(*ppos);
+
+ if (index >= VFIO_CCW_NUM_REGIONS + private->num_regions)
+ return -EINVAL;
+
+ switch (index) {
+ case VFIO_CCW_CONFIG_REGION_INDEX:
+ return vfio_ccw_mdev_read_io_region(private, buf, count, ppos);
+ default:
+ index -= VFIO_CCW_NUM_REGIONS;
+ return private->region[index].ops->read(private, buf, count,
+ ppos);
+ }
+
+ return -EINVAL;
+}
+
+static ssize_t vfio_ccw_mdev_write_io_region(struct vfio_ccw_private *private,
+ const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ loff_t pos = *ppos & VFIO_CCW_OFFSET_MASK;
+ struct ccw_io_region *region;
+ int ret;
+
+ if (pos + count > sizeof(*region))
+ return -EINVAL;
+
+ if (!mutex_trylock(&private->io_mutex))
+ return -EAGAIN;
+
+ region = private->io_region;
+ if (copy_from_user((void *)region + pos, buf, count)) {
+ ret = -EFAULT;
+ goto out_unlock;
+ }
+
+ vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_IO_REQ);
+ ret = (region->ret_code != 0) ? region->ret_code : count;
+
+out_unlock:
+ mutex_unlock(&private->io_mutex);
+ return ret;
+}
+
+static ssize_t vfio_ccw_mdev_write(struct vfio_device *vdev,
+ const char __user *buf,
+ size_t count,
+ loff_t *ppos)
+{
+ struct vfio_ccw_private *private =
+ container_of(vdev, struct vfio_ccw_private, vdev);
+ unsigned int index = VFIO_CCW_OFFSET_TO_INDEX(*ppos);
+
+ if (index >= VFIO_CCW_NUM_REGIONS + private->num_regions)
+ return -EINVAL;
+
+ switch (index) {
+ case VFIO_CCW_CONFIG_REGION_INDEX:
+ return vfio_ccw_mdev_write_io_region(private, buf, count, ppos);
+ default:
+ index -= VFIO_CCW_NUM_REGIONS;
+ return private->region[index].ops->write(private, buf, count,
+ ppos);
+ }
+
+ return -EINVAL;
+}
+
+static int vfio_ccw_mdev_get_device_info(struct vfio_ccw_private *private,
+ struct vfio_device_info *info)
+{
+ info->flags = VFIO_DEVICE_FLAGS_CCW | VFIO_DEVICE_FLAGS_RESET;
+ info->num_regions = VFIO_CCW_NUM_REGIONS + private->num_regions;
+ info->num_irqs = VFIO_CCW_NUM_IRQS;
+
+ return 0;
+}
+
+static int vfio_ccw_mdev_get_region_info(struct vfio_ccw_private *private,
+ struct vfio_region_info *info,
+ unsigned long arg)
+{
+ int i;
+
+ switch (info->index) {
+ case VFIO_CCW_CONFIG_REGION_INDEX:
+ info->offset = 0;
+ info->size = sizeof(struct ccw_io_region);
+ info->flags = VFIO_REGION_INFO_FLAG_READ
+ | VFIO_REGION_INFO_FLAG_WRITE;
+ return 0;
+ default: /* all other regions are handled via capability chain */
+ {
+ struct vfio_info_cap caps = { .buf = NULL, .size = 0 };
+ struct vfio_region_info_cap_type cap_type = {
+ .header.id = VFIO_REGION_INFO_CAP_TYPE,
+ .header.version = 1 };
+ int ret;
+
+ if (info->index >=
+ VFIO_CCW_NUM_REGIONS + private->num_regions)
+ return -EINVAL;
+
+ info->index = array_index_nospec(info->index,
+ VFIO_CCW_NUM_REGIONS +
+ private->num_regions);
+
+ i = info->index - VFIO_CCW_NUM_REGIONS;
+
+ info->offset = VFIO_CCW_INDEX_TO_OFFSET(info->index);
+ info->size = private->region[i].size;
+ info->flags = private->region[i].flags;
+
+ cap_type.type = private->region[i].type;
+ cap_type.subtype = private->region[i].subtype;
+
+ ret = vfio_info_add_capability(&caps, &cap_type.header,
+ sizeof(cap_type));
+ if (ret)
+ return ret;
+
+ info->flags |= VFIO_REGION_INFO_FLAG_CAPS;
+ if (info->argsz < sizeof(*info) + caps.size) {
+ info->argsz = sizeof(*info) + caps.size;
+ info->cap_offset = 0;
+ } else {
+ vfio_info_cap_shift(&caps, sizeof(*info));
+ if (copy_to_user((void __user *)arg + sizeof(*info),
+ caps.buf, caps.size)) {
+ kfree(caps.buf);
+ return -EFAULT;
+ }
+ info->cap_offset = sizeof(*info);
+ }
+
+ kfree(caps.buf);
+
+ }
+ }
+ return 0;
+}
+
+static int vfio_ccw_mdev_get_irq_info(struct vfio_irq_info *info)
+{
+ switch (info->index) {
+ case VFIO_CCW_IO_IRQ_INDEX:
+ case VFIO_CCW_CRW_IRQ_INDEX:
+ case VFIO_CCW_REQ_IRQ_INDEX:
+ info->count = 1;
+ info->flags = VFIO_IRQ_INFO_EVENTFD;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int vfio_ccw_mdev_set_irqs(struct vfio_ccw_private *private,
+ uint32_t flags,
+ uint32_t index,
+ void __user *data)
+{
+ struct eventfd_ctx **ctx;
+
+ if (!(flags & VFIO_IRQ_SET_ACTION_TRIGGER))
+ return -EINVAL;
+
+ switch (index) {
+ case VFIO_CCW_IO_IRQ_INDEX:
+ ctx = &private->io_trigger;
+ break;
+ case VFIO_CCW_CRW_IRQ_INDEX:
+ ctx = &private->crw_trigger;
+ break;
+ case VFIO_CCW_REQ_IRQ_INDEX:
+ ctx = &private->req_trigger;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ switch (flags & VFIO_IRQ_SET_DATA_TYPE_MASK) {
+ case VFIO_IRQ_SET_DATA_NONE:
+ {
+ if (*ctx)
+ eventfd_signal(*ctx, 1);
+ return 0;
+ }
+ case VFIO_IRQ_SET_DATA_BOOL:
+ {
+ uint8_t trigger;
+
+ if (get_user(trigger, (uint8_t __user *)data))
+ return -EFAULT;
+
+ if (trigger && *ctx)
+ eventfd_signal(*ctx, 1);
+ return 0;
+ }
+ case VFIO_IRQ_SET_DATA_EVENTFD:
+ {
+ int32_t fd;
+
+ if (get_user(fd, (int32_t __user *)data))
+ return -EFAULT;
+
+ if (fd == -1) {
+ if (*ctx)
+ eventfd_ctx_put(*ctx);
+ *ctx = NULL;
+ } else if (fd >= 0) {
+ struct eventfd_ctx *efdctx;
+
+ efdctx = eventfd_ctx_fdget(fd);
+ if (IS_ERR(efdctx))
+ return PTR_ERR(efdctx);
+
+ if (*ctx)
+ eventfd_ctx_put(*ctx);
+
+ *ctx = efdctx;
+ } else
+ return -EINVAL;
+
+ return 0;
+ }
+ default:
+ return -EINVAL;
+ }
+}
+
+int vfio_ccw_register_dev_region(struct vfio_ccw_private *private,
+ unsigned int subtype,
+ const struct vfio_ccw_regops *ops,
+ size_t size, u32 flags, void *data)
+{
+ struct vfio_ccw_region *region;
+
+ region = krealloc(private->region,
+ (private->num_regions + 1) * sizeof(*region),
+ GFP_KERNEL);
+ if (!region)
+ return -ENOMEM;
+
+ private->region = region;
+ private->region[private->num_regions].type = VFIO_REGION_TYPE_CCW;
+ private->region[private->num_regions].subtype = subtype;
+ private->region[private->num_regions].ops = ops;
+ private->region[private->num_regions].size = size;
+ private->region[private->num_regions].flags = flags;
+ private->region[private->num_regions].data = data;
+
+ private->num_regions++;
+
+ return 0;
+}
+
+void vfio_ccw_unregister_dev_regions(struct vfio_ccw_private *private)
+{
+ int i;
+
+ for (i = 0; i < private->num_regions; i++)
+ private->region[i].ops->release(private, &private->region[i]);
+ private->num_regions = 0;
+ kfree(private->region);
+ private->region = NULL;
+}
+
+static ssize_t vfio_ccw_mdev_ioctl(struct vfio_device *vdev,
+ unsigned int cmd,
+ unsigned long arg)
+{
+ struct vfio_ccw_private *private =
+ container_of(vdev, struct vfio_ccw_private, vdev);
+ int ret = 0;
+ unsigned long minsz;
+
+ switch (cmd) {
+ case VFIO_DEVICE_GET_INFO:
+ {
+ 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;
+
+ ret = vfio_ccw_mdev_get_device_info(private, &info);
+ if (ret)
+ return ret;
+
+ return copy_to_user((void __user *)arg, &info, minsz) ? -EFAULT : 0;
+ }
+ case VFIO_DEVICE_GET_REGION_INFO:
+ {
+ struct vfio_region_info info;
+
+ minsz = offsetofend(struct vfio_region_info, offset);
+
+ if (copy_from_user(&info, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ if (info.argsz < minsz)
+ return -EINVAL;
+
+ ret = vfio_ccw_mdev_get_region_info(private, &info, arg);
+ if (ret)
+ return ret;
+
+ return copy_to_user((void __user *)arg, &info, minsz) ? -EFAULT : 0;
+ }
+ case VFIO_DEVICE_GET_IRQ_INFO:
+ {
+ struct vfio_irq_info info;
+
+ minsz = offsetofend(struct vfio_irq_info, count);
+
+ if (copy_from_user(&info, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ if (info.argsz < minsz || info.index >= VFIO_CCW_NUM_IRQS)
+ return -EINVAL;
+
+ ret = vfio_ccw_mdev_get_irq_info(&info);
+ if (ret)
+ return ret;
+
+ if (info.count == -1)
+ return -EINVAL;
+
+ return copy_to_user((void __user *)arg, &info, minsz) ? -EFAULT : 0;
+ }
+ case VFIO_DEVICE_SET_IRQS:
+ {
+ struct vfio_irq_set hdr;
+ size_t data_size;
+ void __user *data;
+
+ minsz = offsetofend(struct vfio_irq_set, count);
+
+ if (copy_from_user(&hdr, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ ret = vfio_set_irqs_validate_and_prepare(&hdr, 1,
+ VFIO_CCW_NUM_IRQS,
+ &data_size);
+ if (ret)
+ return ret;
+
+ data = (void __user *)(arg + minsz);
+ return vfio_ccw_mdev_set_irqs(private, hdr.flags, hdr.index,
+ data);
+ }
+ case VFIO_DEVICE_RESET:
+ return vfio_ccw_mdev_reset(private);
+ default:
+ return -ENOTTY;
+ }
+}
+
+/* Request removal of the device*/
+static void vfio_ccw_mdev_request(struct vfio_device *vdev, unsigned int count)
+{
+ struct vfio_ccw_private *private =
+ container_of(vdev, struct vfio_ccw_private, vdev);
+ struct device *dev = vdev->dev;
+
+ if (private->req_trigger) {
+ if (!(count % 10))
+ dev_notice_ratelimited(dev,
+ "Relaying device request to user (#%u)\n",
+ count);
+
+ eventfd_signal(private->req_trigger, 1);
+ } else if (count == 0) {
+ dev_notice(dev,
+ "No device request channel registered, blocked until released by user\n");
+ }
+}
+
+static const struct vfio_device_ops vfio_ccw_dev_ops = {
+ .init = vfio_ccw_mdev_init_dev,
+ .release = vfio_ccw_mdev_release_dev,
+ .open_device = vfio_ccw_mdev_open_device,
+ .close_device = vfio_ccw_mdev_close_device,
+ .read = vfio_ccw_mdev_read,
+ .write = vfio_ccw_mdev_write,
+ .ioctl = vfio_ccw_mdev_ioctl,
+ .request = vfio_ccw_mdev_request,
+ .dma_unmap = vfio_ccw_dma_unmap,
+};
+
+struct mdev_driver vfio_ccw_mdev_driver = {
+ .device_api = VFIO_DEVICE_API_CCW_STRING,
+ .max_instances = 1,
+ .driver = {
+ .name = "vfio_ccw_mdev",
+ .owner = THIS_MODULE,
+ .mod_name = KBUILD_MODNAME,
+ },
+ .probe = vfio_ccw_mdev_probe,
+ .remove = vfio_ccw_mdev_remove,
+};
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-30 22:22:06 +0000