[PATCH v3 1/3] uacce: supports device isolation feature

[Kai Ye via Linux-accelerators <linux-accelerators@xxxxxxxxxxxxxxxx>]

UACCE adds the hardware error isolation API. Users can configure
the isolation method command by this sysfs node. This API interface
certainly supports the configuration of user protocol strategy. Then
parse it inside the device driver. UACCE only reports the device
isolate state. e.g. When the error frequency is exceeded, the device
will be isolated. The isolation strategy should be defined in each
driver module.

Signed-off-by: Kai Ye <yekai13@xxxxxxxxxx>
---
 drivers/misc/uacce/uacce.c | 41 ++++++++++++++++++++++++++++++++++++++
 include/linux/uacce.h      | 11 ++++++++++
 2 files changed, 52 insertions(+)

diff --git a/drivers/misc/uacce/uacce.c b/drivers/misc/uacce/uacce.c
index b6219c6bfb48..440144fea656 100644
--- a/drivers/misc/uacce/uacce.c
+++ b/drivers/misc/uacce/uacce.c
@@ -346,12 +346,51 @@ static ssize_t region_dus_size_show(struct device *dev,
 		       uacce->qf_pg_num[UACCE_QFRT_DUS] << PAGE_SHIFT);
 }
 
+static ssize_t isolate_show(struct device *dev,
+			    struct device_attribute *attr, char *buf)
+{
+	struct uacce_device *uacce = to_uacce_device(dev);
+
+	if (!uacce->ops->get_isolate_state)
+		return -ENODEV;
+
+	return sysfs_emit(buf, "%d\n", uacce->ops->get_isolate_state(uacce));
+}
+
+static ssize_t isolate_strategy_show(struct device *dev,
+				     struct device_attribute *attr, char *buf)
+{
+	struct uacce_device *uacce = to_uacce_device(dev);
+
+	if (!uacce->ops->isolate_strategy_read)
+		return -ENODEV;
+
+	return uacce->ops->isolate_strategy_read(uacce, buf);
+}
+
+static ssize_t isolate_strategy_store(struct device *dev,
+				      struct device_attribute *attr,
+				      const char *buf, size_t count)
+{
+	struct uacce_device *uacce = to_uacce_device(dev);
+	int ret;
+
+	if (!uacce->ops->isolate_strategy_write)
+		return -ENODEV;
+
+	ret = uacce->ops->isolate_strategy_write(uacce, buf, count);
+
+	return ret ? ret : count;
+}
+
 static DEVICE_ATTR_RO(api);
 static DEVICE_ATTR_RO(flags);
 static DEVICE_ATTR_RO(available_instances);
 static DEVICE_ATTR_RO(algorithms);
 static DEVICE_ATTR_RO(region_mmio_size);
 static DEVICE_ATTR_RO(region_dus_size);
+static DEVICE_ATTR_RO(isolate);
+static DEVICE_ATTR_RW(isolate_strategy);
 
 static struct attribute *uacce_dev_attrs[] = {
 	&dev_attr_api.attr,
@@ -360,6 +399,8 @@ static struct attribute *uacce_dev_attrs[] = {
 	&dev_attr_algorithms.attr,
 	&dev_attr_region_mmio_size.attr,
 	&dev_attr_region_dus_size.attr,
+	&dev_attr_isolate.attr,
+	&dev_attr_isolate_strategy.attr,
 	NULL,
 };
 
diff --git a/include/linux/uacce.h b/include/linux/uacce.h
index 48e319f40275..a535286d2753 100644
--- a/include/linux/uacce.h
+++ b/include/linux/uacce.h
@@ -30,6 +30,9 @@ struct uacce_qfile_region {
  * @is_q_updated: check whether the task is finished
  * @mmap: mmap addresses of queue to user space
  * @ioctl: ioctl for user space users of the queue
+ * @get_isolate_state: get the device state after set the isolate strategy
+ * @isolate_strategy_write: stored the isolate strategy to the device
+ * @isolate_strategy_read: read the isolate strategy from the device
  */
 struct uacce_ops {
 	int (*get_available_instances)(struct uacce_device *uacce);
@@ -43,6 +46,9 @@ struct uacce_ops {
 		    struct uacce_qfile_region *qfr);
 	long (*ioctl)(struct uacce_queue *q, unsigned int cmd,
 		      unsigned long arg);
+	enum uacce_dev_state (*get_isolate_state)(struct uacce_device *uacce);
+	int (*isolate_strategy_write)(struct uacce_device *uacce, const char *buf, size_t count);
+	int (*isolate_strategy_read)(struct uacce_device *uacce, char *buf);
 };
 
 /**
@@ -57,6 +63,11 @@ struct uacce_interface {
 	const struct uacce_ops *ops;
 };
 
+enum uacce_dev_state {
+	UACCE_DEV_NORMAL,
+	UACCE_DEV_ISOLATE,
+};
+
 enum uacce_q_state {
 	UACCE_Q_ZOMBIE = 0,
 	UACCE_Q_INIT,
-- 
2.33.0