[dpdk-dev] [PATCH V18 1/5] bus: introduce device hot unplug handle

[Jeff Guo <jia.guo@intel.com>]

As of device hot unplug, we need some preparatory measures so that we will
not encounter memory fault after device have been plug out of the system,
and also let we could recover the running data path but not been break.
This allows the buses to handle device hot unplug event.
In the following patch, will show how to handle the case for pci bus.

Signed-off-by: Jeff Guo <jia.guo@intel.com>
---
v16->v15:
split patch, and remove the ops from RTE_VERIFY
---
 lib/librte_eal/common/include/rte_bus.h | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/lib/librte_eal/common/include/rte_bus.h b/lib/librte_eal/common/include/rte_bus.h
index 6fb0834..ecd8b1c 100644
--- a/lib/librte_eal/common/include/rte_bus.h
+++ b/lib/librte_eal/common/include/rte_bus.h
@@ -168,6 +168,19 @@ typedef int (*rte_bus_unplug_t)(struct rte_device *dev);
 typedef int (*rte_bus_parse_t)(const char *name, void *addr);
 
 /**
+ * Implementation specific hot unplug handler function which is responsible
+ * for handle the failure when hot unplug the device, guaranty the system
+ * would not crash in the case.
+ * @param dev
+ *	Pointer of the device structure.
+ *
+ * @return
+ *	0 on success.
+ *	!0 on error.
+ */
+typedef int (*rte_bus_handle_hot_unplug_t)(struct rte_device *dev);
+
+/**
  * Bus scan policies
  */
 enum rte_bus_scan_mode {
@@ -209,6 +222,8 @@ struct rte_bus {
 	rte_bus_plug_t plug;         /**< Probe single device for drivers */
 	rte_bus_unplug_t unplug;     /**< Remove single device from driver */
 	rte_bus_parse_t parse;       /**< Parse a device name */
+	rte_bus_handle_hot_unplug_t handle_hot_unplug; /**< handle when device
+							hot unplug */
 	struct rte_bus_conf conf;    /**< Bus configuration */
 	rte_bus_get_iommu_class_t get_iommu_class; /**< Get iommu class */
 };
-- 
2.7.4