vfio/mdev: consolidate all the available_instance sysfs into the core code

Every driver just print a number, simply add a method to the mdev_driver
to return it and provide a standard sysfs show function.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Link: https://lore.kernel.org/r/20220923092652.100656-13-hch@lst.de
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 dcd1231..558bd7e 100644 (file)
--- a/Documentation/driver-api/vfio-mediated-device.rst
+++ b/Documentation/driver-api/vfio-mediated-device.rst
@@ -103,6 +103,7 @@ structure to represent a mediated device's driver::
      struct mdev_driver {
             int  (*probe)  (struct mdev_device *dev);
             void (*remove) (struct mdev_device *dev);
+            unsigned int (*get_available)(struct mdev_type *mtype);
             const struct attribute * const *types_attrs;
             struct device_driver    driver;
      };
@@ -207,7 +208,7 @@ Directories and files under the sysfs for Each Physical Device
 
 * available_instances
 
-  This attribute should show the number of devices of type <type-id> that can be
+  This attribute shows the number of devices of type <type-id> that can be
   created.
 
 * [device]

diff --git a/drivers/gpu/drm/i915/gvt/gvt.h b/drivers/gpu/drm/i915/gvt/gvt.h
index db18206..dbf8d74 100644 (file)
--- a/drivers/gpu/drm/i915/gvt/gvt.h
+++ b/drivers/gpu/drm/i915/gvt/gvt.h
@@ -314,7 +314,6 @@ struct intel_vgpu_type {
        struct mdev_type type;
        char name[16];
        const struct intel_vgpu_config *conf;
-       unsigned int avail_instance;
 };
 
 struct intel_gvt {

diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
index 93a52ae..45051ae 100644 (file)
--- a/drivers/gpu/drm/i915/gvt/kvmgt.c
+++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
@@ -113,16 +113,6 @@ static void kvmgt_page_track_flush_slot(struct kvm *kvm,
                struct kvm_memory_slot *slot,
                struct kvm_page_track_notifier_node *node);
 
-static ssize_t available_instances_show(struct mdev_type *mtype,
-                                       struct mdev_type_attribute *attr,
-                                       char *buf)
-{
-       struct intel_vgpu_type *type =
-               container_of(mtype, struct intel_vgpu_type, type);
-
-       return sprintf(buf, "%u\n", type->avail_instance);
-}
-
 static ssize_t description_show(struct mdev_type *mtype,
                                struct mdev_type_attribute *attr, char *buf)
 {
@@ -138,11 +128,9 @@ static ssize_t description_show(struct mdev_type *mtype,
                       type->conf->weight);
 }
 
-static MDEV_TYPE_ATTR_RO(available_instances);
 static MDEV_TYPE_ATTR_RO(description);
 
 static const struct attribute *gvt_type_attrs[] = {
-       &mdev_type_attr_available_instances.attr,
        &mdev_type_attr_description.attr,
        NULL,
 };
@@ -1533,6 +1521,27 @@ static void intel_vgpu_remove(struct mdev_device *mdev)
        vfio_put_device(&vgpu->vfio_device);
 }
 
+static unsigned int intel_vgpu_get_available(struct mdev_type *mtype)
+{
+       struct intel_vgpu_type *type =
+               container_of(mtype, struct intel_vgpu_type, type);
+       struct intel_gvt *gvt = kdev_to_i915(mtype->parent->dev)->gvt;
+       unsigned int low_gm_avail, high_gm_avail, fence_avail;
+
+       mutex_lock(&gvt->lock);
+       low_gm_avail = gvt_aperture_sz(gvt) - HOST_LOW_GM_SIZE -
+               gvt->gm.vgpu_allocated_low_gm_size;
+       high_gm_avail = gvt_hidden_sz(gvt) - HOST_HIGH_GM_SIZE -
+               gvt->gm.vgpu_allocated_high_gm_size;
+       fence_avail = gvt_fence_sz(gvt) - HOST_FENCE -
+               gvt->fence.vgpu_allocated_fence_num;
+       mutex_unlock(&gvt->lock);
+
+       return min3(low_gm_avail / type->conf->low_mm,
+                   high_gm_avail / type->conf->high_mm,
+                   fence_avail / type->conf->fence);
+}
+
 static struct mdev_driver intel_vgpu_mdev_driver = {
        .device_api     = VFIO_DEVICE_API_PCI_STRING,
        .driver = {
@@ -1542,6 +1551,7 @@ static struct mdev_driver intel_vgpu_mdev_driver = {
        },
        .probe          = intel_vgpu_probe,
        .remove         = intel_vgpu_remove,
+       .get_available  = intel_vgpu_get_available,
        .types_attrs    = gvt_type_attrs,
 };
 

diff --git a/drivers/gpu/drm/i915/gvt/vgpu.c b/drivers/gpu/drm/i915/gvt/vgpu.c
index 92aaa77..56c7147 100644 (file)
--- a/drivers/gpu/drm/i915/gvt/vgpu.c
+++ b/drivers/gpu/drm/i915/gvt/vgpu.c
@@ -129,11 +129,11 @@ int intel_gvt_init_vgpu_types(struct intel_gvt *gvt)
                sprintf(gvt->types[i].name, "GVTg_V%u_%s",
                        GRAPHICS_VER(gvt->gt->i915) == 8 ? 4 : 5, conf->name);
                gvt->types[i].conf = conf;
-               gvt->types[i].avail_instance = min(low_avail / conf->low_mm,
-                                                  high_avail / conf->high_mm);
 
                gvt_dbg_core("type[%d]: %s avail %u low %u high %u fence %u weight %u res %s\n",
-                            i, gvt->types[i].name, gvt->types[i].avail_instance,
+                            i, gvt->types[i].name,
+                            min(low_avail / conf->low_mm,
+                                high_avail / conf->high_mm),
                             conf->low_mm, conf->high_mm, conf->fence,
                             conf->weight, vgpu_edid_str(conf->edid));
 
@@ -157,36 +157,6 @@ void intel_gvt_clean_vgpu_types(struct intel_gvt *gvt)
        kfree(gvt->types);
 }
 
-static void intel_gvt_update_vgpu_types(struct intel_gvt *gvt)
-{
-       int i;
-       unsigned int low_gm_avail, high_gm_avail, fence_avail;
-       unsigned int low_gm_min, high_gm_min, fence_min;
-
-       /* Need to depend on maxium hw resource size but keep on
-        * static config for now.
-        */
-       low_gm_avail = gvt_aperture_sz(gvt) - HOST_LOW_GM_SIZE -
-               gvt->gm.vgpu_allocated_low_gm_size;
-       high_gm_avail = gvt_hidden_sz(gvt) - HOST_HIGH_GM_SIZE -
-               gvt->gm.vgpu_allocated_high_gm_size;
-       fence_avail = gvt_fence_sz(gvt) - HOST_FENCE -
-               gvt->fence.vgpu_allocated_fence_num;
-
-       for (i = 0; i < gvt->num_types; i++) {
-               low_gm_min = low_gm_avail / gvt->types[i].conf->low_mm;
-               high_gm_min = high_gm_avail / gvt->types[i].conf->high_mm;
-               fence_min = fence_avail / gvt->types[i].conf->fence;
-               gvt->types[i].avail_instance = min(min(low_gm_min, high_gm_min),
-                                                  fence_min);
-
-               gvt_dbg_core("update type[%d]: %s avail %u low %u high %u fence %u\n",
-                      i, gvt->types[i].name,
-                      gvt->types[i].avail_instance, gvt->types[i].conf->low_mm,
-                      gvt->types[i].conf->high_mm, gvt->types[i].conf->fence);
-       }
-}
-
 /**
  * intel_gvt_active_vgpu - activate a virtual GPU
  * @vgpu: virtual GPU
@@ -281,10 +251,6 @@ void intel_gvt_destroy_vgpu(struct intel_vgpu *vgpu)
        intel_vgpu_clean_mmio(vgpu);
        intel_vgpu_dmabuf_cleanup(vgpu);
        mutex_unlock(&vgpu->vgpu_lock);
-
-       mutex_lock(&gvt->lock);
-       intel_gvt_update_vgpu_types(gvt);
-       mutex_unlock(&gvt->lock);
 }
 
 #define IDLE_VGPU_IDR 0
@@ -414,7 +380,6 @@ int intel_gvt_create_vgpu(struct intel_vgpu *vgpu,
        if (ret)
                goto out_clean_sched_policy;
 
-       intel_gvt_update_vgpu_types(gvt);
        intel_gvt_update_reg_whitelist(vgpu);
        mutex_unlock(&gvt->lock);
        return 0;

diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c
index 394aab6..559ca18 100644 (file)
--- a/drivers/s390/cio/vfio_ccw_ops.c
+++ b/drivers/s390/cio/vfio_ccw_ops.c
@@ -44,20 +44,12 @@ static void vfio_ccw_dma_unmap(struct vfio_device *vdev, u64 iova, u64 length)
        vfio_ccw_mdev_reset(private);
 }
 
-static ssize_t available_instances_show(struct mdev_type *mtype,
-                                       struct mdev_type_attribute *attr,
-                                       char *buf)
+static unsigned int vfio_ccw_get_available(struct mdev_type *mtype)
 {
        struct vfio_ccw_private *private = dev_get_drvdata(mtype->parent->dev);
 
-       return sprintf(buf, "%d\n", atomic_read(&private->avail));
+       return atomic_read(&private->avail);
 }
-static MDEV_TYPE_ATTR_RO(available_instances);
-
-static const struct attribute *mdev_types_attrs[] = {
-       &mdev_type_attr_available_instances.attr,
-       NULL,
-};
 
 static int vfio_ccw_mdev_init_dev(struct vfio_device *vdev)
 {
@@ -620,5 +612,5 @@ struct mdev_driver vfio_ccw_mdev_driver = {
        },
        .probe = vfio_ccw_mdev_probe,
        .remove = vfio_ccw_mdev_remove,
-       .types_attrs = mdev_types_attrs,
+       .get_available = vfio_ccw_get_available,
 };

diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
index 5d8dd7e..8606f5d 100644 (file)
--- a/drivers/s390/crypto/vfio_ap_ops.c
+++ b/drivers/s390/crypto/vfio_ap_ops.c
@@ -790,21 +790,11 @@ static void vfio_ap_mdev_remove(struct mdev_device *mdev)
        vfio_put_device(&matrix_mdev->vdev);
 }
 
-static ssize_t available_instances_show(struct mdev_type *mtype,
-                                       struct mdev_type_attribute *attr,
-                                       char *buf)
+static unsigned int vfio_ap_mdev_get_available(struct mdev_type *mtype)
 {
-       return sprintf(buf, "%d\n",
-                      atomic_read(&matrix_dev->available_instances));
+       return atomic_read(&matrix_dev->available_instances);
 }
 
-static MDEV_TYPE_ATTR_RO(available_instances);
-
-static const struct attribute *vfio_ap_mdev_type_attrs[] = {
-       &mdev_type_attr_available_instances.attr,
-       NULL,
-};
-
 #define MDEV_SHARING_ERR "Userspace may not re-assign queue %02lx.%04lx " \
                         "already assigned to %s"
 
@@ -1790,7 +1780,7 @@ static struct mdev_driver vfio_ap_matrix_driver = {
        },
        .probe = vfio_ap_mdev_probe,
        .remove = vfio_ap_mdev_remove,
-       .types_attrs = vfio_ap_mdev_type_attrs,
+       .get_available = vfio_ap_mdev_get_available,
 };
 
 int vfio_ap_mdev_register(void)

diff --git a/drivers/vfio/mdev/mdev_sysfs.c b/drivers/vfio/mdev/mdev_sysfs.c
index 34583e6..b7f87c3 100644 (file)
--- a/drivers/vfio/mdev/mdev_sysfs.c
+++ b/drivers/vfio/mdev/mdev_sysfs.c
@@ -90,10 +90,21 @@ static ssize_t name_show(struct mdev_type *mtype,
 
 static MDEV_TYPE_ATTR_RO(name);
 
+static ssize_t available_instances_show(struct mdev_type *mtype,
+                                       struct mdev_type_attribute *attr,
+                                       char *buf)
+{
+       struct mdev_driver *drv = mtype->parent->mdev_driver;
+
+       return sysfs_emit(buf, "%u\n", drv->get_available(mtype));
+}
+static MDEV_TYPE_ATTR_RO(available_instances);
+
 static struct attribute *mdev_types_core_attrs[] = {
        &mdev_type_attr_create.attr,
        &mdev_type_attr_device_api.attr,
        &mdev_type_attr_name.attr,
+       &mdev_type_attr_available_instances.attr,
        NULL,
 };
 

diff --git a/include/linux/mdev.h b/include/linux/mdev.h
index 4bb8a58..d39e08a 100644 (file)
--- a/include/linux/mdev.h
+++ b/include/linux/mdev.h
@@ -72,6 +72,7 @@ struct mdev_type_attribute {
  * @device_api: string to return for the device_api sysfs
  * @probe: called when new device created
  * @remove: called when device removed
+ * @get_available: Return the max number of instances that can be created
  * @types_attrs: attributes to the type kobjects.
  * @driver: device driver structure
  **/
@@ -79,6 +80,7 @@ struct mdev_driver {
        const char *device_api;
        int (*probe)(struct mdev_device *dev);
        void (*remove)(struct mdev_device *dev);
+       unsigned int (*get_available)(struct mdev_type *mtype);
        const struct attribute * const *types_attrs;
        struct device_driver driver;
 };

diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c
index 0b7585f..6c2cbc4 100644 (file)
--- a/samples/vfio-mdev/mbochs.c
+++ b/samples/vfio-mdev/mbochs.c
@@ -1361,21 +1361,16 @@ static ssize_t description_show(struct mdev_type *mtype,
 }
 static MDEV_TYPE_ATTR_RO(description);
 
-static ssize_t available_instances_show(struct mdev_type *mtype,
-                                       struct mdev_type_attribute *attr,
-                                       char *buf)
+static unsigned int mbochs_get_available(struct mdev_type *mtype)
 {
        struct mbochs_type *type =
                container_of(mtype, struct mbochs_type, type);
-       int count = atomic_read(&mbochs_avail_mbytes) / type->mbytes;
 
-       return sprintf(buf, "%d\n", count);
+       return atomic_read(&mbochs_avail_mbytes) / type->mbytes;
 }
-static MDEV_TYPE_ATTR_RO(available_instances);
 
 static const struct attribute *mdev_types_attrs[] = {
        &mdev_type_attr_description.attr,
-       &mdev_type_attr_available_instances.attr,
        NULL,
 };
 
@@ -1399,6 +1394,7 @@ static struct mdev_driver mbochs_driver = {
        },
        .probe = mbochs_probe,
        .remove = mbochs_remove,
+       .get_available = mbochs_get_available,
        .types_attrs = mdev_types_attrs,
 };
 

diff --git a/samples/vfio-mdev/mdpy.c b/samples/vfio-mdev/mdpy.c
index 90c6fed..d1c835c 100644 (file)
--- a/samples/vfio-mdev/mdpy.c
+++ b/samples/vfio-mdev/mdpy.c
@@ -671,17 +671,13 @@ static ssize_t description_show(struct mdev_type *mtype,
 }
 static MDEV_TYPE_ATTR_RO(description);
 
-static ssize_t available_instances_show(struct mdev_type *mtype,
-                                       struct mdev_type_attribute *attr,
-                                       char *buf)
+static unsigned int mdpy_get_available(struct mdev_type *mtype)
 {
-       return sprintf(buf, "%d\n", max_devices - mdpy_count);
+       return max_devices - mdpy_count;
 }
-static MDEV_TYPE_ATTR_RO(available_instances);
 
 static const struct attribute *mdev_types_attrs[] = {
        &mdev_type_attr_description.attr,
-       &mdev_type_attr_available_instances.attr,
        NULL,
 };
 
@@ -704,6 +700,7 @@ static struct mdev_driver mdpy_driver = {
        },
        .probe = mdpy_probe,
        .remove = mdpy_remove,
+       .get_available = mdpy_get_available,
        .types_attrs = mdev_types_attrs,
 };
 

diff --git a/samples/vfio-mdev/mtty.c b/samples/vfio-mdev/mtty.c
index eab1b44..e72085f 100644 (file)
--- a/samples/vfio-mdev/mtty.c
+++ b/samples/vfio-mdev/mtty.c
@@ -1256,23 +1256,13 @@ static const struct attribute_group *mdev_dev_groups[] = {
        NULL,
 };
 
-static ssize_t available_instances_show(struct mdev_type *mtype,
-                                       struct mdev_type_attribute *attr,
-                                       char *buf)
+static unsigned int mtty_get_available(struct mdev_type *mtype)
 {
        struct mtty_type *type = container_of(mtype, struct mtty_type, type);
 
-       return sprintf(buf, "%d\n", atomic_read(&mdev_avail_ports) /
-                       type->nr_ports);
+       return atomic_read(&mdev_avail_ports) / type->nr_ports;
 }
 
-static MDEV_TYPE_ATTR_RO(available_instances);
-
-static const struct attribute *mdev_types_attrs[] = {
-       &mdev_type_attr_available_instances.attr,
-       NULL,
-};
-
 static const struct vfio_device_ops mtty_dev_ops = {
        .name = "vfio-mtty",
        .init = mtty_init_dev,
@@ -1292,7 +1282,7 @@ static struct mdev_driver mtty_driver = {
        },
        .probe = mtty_probe,
        .remove = mtty_remove,
-       .types_attrs = mdev_types_attrs,
+       .get_available = mtty_get_available,
 };
 
 static void mtty_device_release(struct device *dev)