For special mdev type which can aggregate instances for mdev device,
this extends mdev create interface by allowing extra "aggregate=xxx"
parameter, which is passed to mdev device model to be able to create
bundled number of instances for target mdev device.
v2: create new create_with_instances operator for vendor driver
v3:
- Change parameter name as "aggregate="
- Fix new interface comments.
- Parameter checking for new option, pass UUID string only to
parse and properly end parameter for kstrtouint() conversion.
Cc: Kirti Wankhede <kwankhede@xxxxxxxxxx>
Cc: Alex Williamson <alex.williamson@xxxxxxxxxx>
Cc: Kevin Tian <kevin.tian@xxxxxxxxx>
Cc: Cornelia Huck <cohuck@xxxxxxxxxx>
Signed-off-by: Zhenyu Wang <zhenyuw@xxxxxxxxxxxxxxx>
---
drivers/vfio/mdev/mdev_core.c | 21 +++++++++++++++++----
drivers/vfio/mdev/mdev_private.h | 4 +++-
drivers/vfio/mdev/mdev_sysfs.c | 32 ++++++++++++++++++++++++++++----
include/linux/mdev.h | 11 +++++++++++
4 files changed, 59 insertions(+), 9 deletions(-)
diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c
index 0212f0ee8aea..545c52ec7618 100644
--- a/drivers/vfio/mdev/mdev_core.c
+++ b/drivers/vfio/mdev/mdev_core.c
@@ -104,12 +104,17 @@ static inline void mdev_put_parent(struct mdev_parent *parent)
}
static int mdev_device_create_ops(struct kobject *kobj,
- struct mdev_device *mdev)
+ struct mdev_device *mdev,
+ unsigned int instances)
{
struct mdev_parent *parent = mdev->parent;
int ret;
- ret = parent->ops->create(kobj, mdev);
+ if (instances > 1) {
+ ret = parent->ops->create_with_instances(kobj, mdev,
+ instances);
+ } else
+ ret = parent->ops->create(kobj, mdev);
if (ret)
return ret;
@@ -276,7 +281,8 @@ static void mdev_device_release(struct device *dev)
kfree(mdev);
}
-int mdev_device_create(struct kobject *kobj, struct device *dev, uuid_le uuid)
+int mdev_device_create(struct kobject *kobj, struct device *dev, uuid_le uuid,
+ unsigned int instances)
{
int ret;
struct mdev_device *mdev, *tmp;
@@ -287,6 +293,12 @@ int mdev_device_create(struct kobject *kobj, struct device *dev, uuid_le uuid)
if (!parent)
return -EINVAL;
+ if (instances > 1 &&
+ !parent->ops->create_with_instances) {
+ ret = -EINVAL;
+ goto mdev_fail;
+ }
+
mutex_lock(&mdev_list_lock);
/* Check for duplicate */
@@ -316,6 +328,7 @@ int mdev_device_create(struct kobject *kobj, struct device *dev, uuid_le uuid)
mdev->dev.bus = &mdev_bus_type;
mdev->dev.release = mdev_device_release;
dev_set_name(&mdev->dev, "%pUl", uuid.b);
+ mdev->type_instances = instances;
ret = device_register(&mdev->dev);
if (ret) {
@@ -323,7 +336,7 @@ int mdev_device_create(struct kobject *kobj, struct device *dev, uuid_le uuid)
goto mdev_fail;
}
- ret = mdev_device_create_ops(kobj, mdev);
+ ret = mdev_device_create_ops(kobj, mdev, instances);
if (ret)
goto create_fail;
diff --git a/drivers/vfio/mdev/mdev_private.h b/drivers/vfio/mdev/mdev_private.h
index b5819b7d7ef7..e90d295d3927 100644
--- a/drivers/vfio/mdev/mdev_private.h
+++ b/drivers/vfio/mdev/mdev_private.h
@@ -33,6 +33,7 @@ struct mdev_device {
struct kref ref;
struct list_head next;
struct kobject *type_kobj;
+ unsigned int type_instances;
bool active;
};
@@ -58,7 +59,8 @@ void parent_remove_sysfs_files(struct mdev_parent *parent);
int mdev_create_sysfs_files(struct device *dev, struct mdev_type *type);
void mdev_remove_sysfs_files(struct device *dev, struct mdev_type *type);
-int mdev_device_create(struct kobject *kobj, struct device *dev, uuid_le uuid);
+int mdev_device_create(struct kobject *kobj, struct device *dev, uuid_le uuid,
+ unsigned int instances);
int mdev_device_remove(struct device *dev, bool force_remove);
#endif /* MDEV_PRIVATE_H */
diff --git a/drivers/vfio/mdev/mdev_sysfs.c b/drivers/vfio/mdev/mdev_sysfs.c
index 249472f05509..aefed0c8891b 100644
--- a/drivers/vfio/mdev/mdev_sysfs.c
+++ b/drivers/vfio/mdev/mdev_sysfs.c
@@ -54,14 +54,21 @@ static const struct sysfs_ops mdev_type_sysfs_ops = {
static ssize_t create_store(struct kobject *kobj, struct device *dev,
const char *buf, size_t count)
{
- char *str;
+ char *str, *param, *opt = NULL;
uuid_le uuid;
int ret;
+ unsigned int instances = 1;
- if ((count < UUID_STRING_LEN) || (count > UUID_STRING_LEN + 1))
+ if (count < UUID_STRING_LEN)
return -EINVAL;
- str = kstrndup(buf, count, GFP_KERNEL);
+ if ((param = strnchr(buf, count, ',')) == NULL) {
+ if (count > UUID_STRING_LEN + 1)
+ return -EINVAL;
+ } else if (param - buf != UUID_STRING_LEN)
+ return -EINVAL;
+
+ str = kstrndup(buf, UUID_STRING_LEN, GFP_KERNEL);
if (!str)
return -ENOMEM;
@@ -70,7 +77,24 @@ static ssize_t create_store(struct kobject *kobj, struct device *dev,
if (ret)
return ret;
- ret = mdev_device_create(kobj, dev, uuid);
+ if (param) {
+ opt = kstrndup(param + 1, count - UUID_STRING_LEN - 1,
+ GFP_KERNEL);
+ if (!opt)
+ return -ENOMEM;
+ if (strncmp(opt, "aggregate=", 10)) {
+ kfree(opt);
+ return -EINVAL;
+ }
+ opt += 10;
+ if (kstrtouint(opt, 10, &instances)) {
+ kfree(opt);
+ return -EINVAL;
+ }
+ kfree(opt);
+ }
+
+ ret = mdev_device_create(kobj, dev, uuid, instances);
if (ret)
return ret;
diff --git a/include/linux/mdev.h b/include/linux/mdev.h
index b6e048e1045f..c12c0bfc5598 100644
--- a/include/linux/mdev.h
+++ b/include/linux/mdev.h
@@ -31,6 +31,14 @@ struct mdev_device;
* @mdev: mdev_device structure on of mediated device
* that is being created
* Returns integer: success (0) or error (< 0)
+ * @create_with_instances: Allocate aggregated instances' resources in parent device's
+ * driver for a particular mediated device. Optional if aggregated
+ * resources are not supported.
+ * @kobj: kobject of type for which 'create' is called.
+ * @mdev: mdev_device structure on of mediated device
+ * that is being created
+ * @instances: number of instances to aggregate
+ * Returns integer: success (0) or error (< 0)
* @remove: Called to free resources in parent device's driver for a
* a mediated device. It is mandatory to provide 'remove'
* ops.
@@ -71,6 +79,9 @@ struct mdev_parent_ops {
struct attribute_group **supported_type_groups;
int (*create)(struct kobject *kobj, struct mdev_device *mdev);
+ int (*create_with_instances)(struct kobject *kobj,
+ struct mdev_device *mdev,
+ unsigned int instances);
int (*remove)(struct mdev_device *mdev);
int (*open)(struct mdev_device *mdev);
void (*release)(struct mdev_device *mdev);
--
2.19.1
