vfio/mdev: Pass in a struct vfio_device * to vfio_pin/unpin_pages()

Every caller has a readily available vfio_device pointer, use that instead
of passing in a generic struct device. The struct vfio_device already
contains the group we need so this avoids complexity, extra refcountings,
and a confusing lifecycle model.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com>
Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/3-v4-8045e76bf00b+13d-vfio_mdev_no_group_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

diff --git a/Documentation/driver-api/vfio-mediated-device.rst b/Documentation/driver-api/vfio-mediated-device.rst
index 784bbeb22adcf559e5b8d0e679560bfe2391cc28..eded8719180fba1aa22efcf09749082fbb15d91b 100644 (file)
--- a/Documentation/driver-api/vfio-mediated-device.rst
+++ b/Documentation/driver-api/vfio-mediated-device.rst
@@ -262,10 +262,10 @@ Translation APIs for Mediated Devices
 The following APIs are provided for translating user pfn to host pfn in a VFIO
 driver::
 
-       extern int vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
+       int vfio_pin_pages(struct vfio_device *device, unsigned long *user_pfn,
                                  int npage, int prot, unsigned long *phys_pfn);
 
-       extern int vfio_unpin_pages(struct device *dev, unsigned long *user_pfn,
+       int vfio_unpin_pages(struct vfio_device *device, unsigned long *user_pfn,
                                    int npage);
 
 These functions call back into the back-end IOMMU module by using the pin_pages

diff --git a/drivers/s390/cio/vfio_ccw_cp.c b/drivers/s390/cio/vfio_ccw_cp.c
index 7a1cf3091cd6470c338f1944a57739e3a213c2a6..0c2be9421ab78fa4e8c7802aa7533a745e3711da 100644 (file)
--- a/drivers/s390/cio/vfio_ccw_cp.c
+++ b/drivers/s390/cio/vfio_ccw_cp.c
@@ -103,13 +103,13 @@ static int pfn_array_pin(struct pfn_array *pa, struct vfio_device *vdev)
 {
        int ret = 0;
 
-       ret = vfio_pin_pages(vdev->dev, pa->pa_iova_pfn, pa->pa_nr,
+       ret = vfio_pin_pages(vdev, pa->pa_iova_pfn, pa->pa_nr,
                             IOMMU_READ | IOMMU_WRITE, pa->pa_pfn);
 
        if (ret < 0) {
                goto err_out;
        } else if (ret > 0 && ret != pa->pa_nr) {
-               vfio_unpin_pages(vdev->dev, pa->pa_iova_pfn, ret);
+               vfio_unpin_pages(vdev, pa->pa_iova_pfn, ret);
                ret = -EINVAL;
                goto err_out;
        }
@@ -127,7 +127,7 @@ static void pfn_array_unpin_free(struct pfn_array *pa, struct vfio_device *vdev)
 {
        /* Only unpin if any pages were pinned to begin with */
        if (pa->pa_nr)
-               vfio_unpin_pages(vdev->dev, pa->pa_iova_pfn, pa->pa_nr);
+               vfio_unpin_pages(vdev, pa->pa_iova_pfn, pa->pa_nr);
        pa->pa_nr = 0;
        kfree(pa->pa_iova_pfn);
 }

diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
index bfa7ee6ef532d9f4d451057e95322826aa1ebc4b..e8914024f5b1af6606f50b901d8f5b4dec0555e0 100644 (file)
--- a/drivers/s390/crypto/vfio_ap_ops.c
+++ b/drivers/s390/crypto/vfio_ap_ops.c
@@ -124,8 +124,7 @@ static void vfio_ap_free_aqic_resources(struct vfio_ap_queue *q)
                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);
+               vfio_unpin_pages(&q->matrix_mdev->vdev, &q->saved_pfn, 1);
                q->saved_pfn = 0;
        }
 }
@@ -258,7 +257,7 @@ static struct ap_queue_status vfio_ap_irq_enable(struct vfio_ap_queue *q,
                return status;
        }
 
-       ret = vfio_pin_pages(mdev_dev(q->matrix_mdev->mdev), &g_pfn, 1,
+       ret = vfio_pin_pages(&q->matrix_mdev->vdev, &g_pfn, 1,
                             IOMMU_READ | IOMMU_WRITE, &h_pfn);
        switch (ret) {
        case 1:
@@ -301,7 +300,7 @@ static struct ap_queue_status vfio_ap_irq_enable(struct vfio_ap_queue *q,
                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);
+               vfio_unpin_pages(&q->matrix_mdev->vdev, &g_pfn, 1);
                kvm_s390_gisc_unregister(kvm, isc);
                break;
        default:
@@ -1250,7 +1249,7 @@ static int vfio_ap_mdev_iommu_notifier(struct notifier_block *nb,
                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);
+               vfio_unpin_pages(&matrix_mdev->vdev, &g_pfn, 1);
                return NOTIFY_OK;
        }
 

diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index cb4730756510047237e73e73dbd170ce7e09f60b..0f85e789fbd39fcb63769cd54adcb2008ea0df69 100644 (file)
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c
@@ -2134,7 +2134,7 @@ EXPORT_SYMBOL(vfio_set_irqs_validate_and_prepare);
 /*
  * Pin a set of guest PFNs and return their associated host PFNs for local
  * domain only.
- * @dev [in]     : device
+ * @device [in]  : device
  * @user_pfn [in]: array of user/guest PFNs to be pinned.
  * @npage [in]   : count of elements in user_pfn array.  This count should not
  *                be greater VFIO_PIN_PAGES_MAX_ENTRIES.
@@ -2142,32 +2142,26 @@ EXPORT_SYMBOL(vfio_set_irqs_validate_and_prepare);
  * @phys_pfn[out]: array of host PFNs
  * Return error or number of pages pinned.
  */
-int vfio_pin_pages(struct device *dev, unsigned long *user_pfn, int npage,
-                  int prot, unsigned long *phys_pfn)
+int vfio_pin_pages(struct vfio_device *device, unsigned long *user_pfn,
+                  int npage, int prot, unsigned long *phys_pfn)
 {
        struct vfio_container *container;
-       struct vfio_group *group;
+       struct vfio_group *group = device->group;
        struct vfio_iommu_driver *driver;
        int ret;
 
-       if (!dev || !user_pfn || !phys_pfn || !npage)
+       if (!user_pfn || !phys_pfn || !npage)
                return -EINVAL;
 
        if (npage > VFIO_PIN_PAGES_MAX_ENTRIES)
                return -E2BIG;
 
-       group = vfio_group_get_from_dev(dev);
-       if (!group)
-               return -ENODEV;
-
-       if (group->dev_counter > 1) {
-               ret = -EINVAL;
-               goto err_pin_pages;
-       }
+       if (group->dev_counter > 1)
+               return -EINVAL;
 
        ret = vfio_group_add_container_user(group);
        if (ret)
-               goto err_pin_pages;
+               return ret;
 
        container = group->container;
        driver = container->iommu_driver;
@@ -2180,43 +2174,37 @@ int vfio_pin_pages(struct device *dev, unsigned long *user_pfn, int npage,
 
        vfio_group_try_dissolve_container(group);
 
-err_pin_pages:
-       vfio_group_put(group);
        return ret;
 }
 EXPORT_SYMBOL(vfio_pin_pages);
 
 /*
  * Unpin set of host PFNs for local domain only.
- * @dev [in]     : device
+ * @device [in]  : device
  * @user_pfn [in]: array of user/guest PFNs to be unpinned. Number of user/guest
  *                PFNs should not be greater than VFIO_PIN_PAGES_MAX_ENTRIES.
  * @npage [in]   : count of elements in user_pfn array.  This count should not
  *                 be greater than VFIO_PIN_PAGES_MAX_ENTRIES.
  * Return error or number of pages unpinned.
  */
-int vfio_unpin_pages(struct device *dev, unsigned long *user_pfn, int npage)
+int vfio_unpin_pages(struct vfio_device *device, unsigned long *user_pfn,
+                    int npage)
 {
        struct vfio_container *container;
-       struct vfio_group *group;
        struct vfio_iommu_driver *driver;
        int ret;
 
-       if (!dev || !user_pfn || !npage)
+       if (!user_pfn || !npage)
                return -EINVAL;
 
        if (npage > VFIO_PIN_PAGES_MAX_ENTRIES)
                return -E2BIG;
 
-       group = vfio_group_get_from_dev(dev);
-       if (!group)
-               return -ENODEV;
-
-       ret = vfio_group_add_container_user(group);
+       ret = vfio_group_add_container_user(device->group);
        if (ret)
-               goto err_unpin_pages;
+               return ret;
 
-       container = group->container;
+       container = device->group->container;
        driver = container->iommu_driver;
        if (likely(driver && driver->ops->unpin_pages))
                ret = driver->ops->unpin_pages(container->iommu_data, user_pfn,
@@ -2224,10 +2212,8 @@ int vfio_unpin_pages(struct device *dev, unsigned long *user_pfn, int npage)
        else
                ret = -ENOTTY;
 
-       vfio_group_try_dissolve_container(group);
+       vfio_group_try_dissolve_container(device->group);
 
-err_unpin_pages:
-       vfio_group_put(group);
        return ret;
 }
 EXPORT_SYMBOL(vfio_unpin_pages);

diff --git a/include/linux/vfio.h b/include/linux/vfio.h
index a00fd722f044b00f995ef67bad92bcb57b3f421d..bddc70f88899c3a3b17d247018c476012a303d75 100644 (file)
--- a/include/linux/vfio.h
+++ b/include/linux/vfio.h
@@ -150,9 +150,9 @@ extern long vfio_external_check_extension(struct vfio_group *group,
 
 #define VFIO_PIN_PAGES_MAX_ENTRIES     (PAGE_SIZE/sizeof(unsigned long))
 
-extern int vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
+extern int vfio_pin_pages(struct vfio_device *device, unsigned long *user_pfn,
                          int npage, int prot, unsigned long *phys_pfn);
-extern int vfio_unpin_pages(struct device *dev, unsigned long *user_pfn,
+extern int vfio_unpin_pages(struct vfio_device *device, unsigned long *user_pfn,
                            int npage);
 
 extern int vfio_group_pin_pages(struct vfio_group *group,