PCI hotplug: create symlink to hotplug driver module

Create symbolic link to hotplug driver module in the PCI slot
directory (/sys/bus/pci/slots/<SLOT#>). In the past, we need to load
hotplug drivers one by one to identify the hotplug driver that handles
the slot, and it was very inconvenient especially for trouble shooting.
With this change, we can easily identify the hotplug driver.

Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Reviewed-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

2 files changed, 18 insertions, 2 deletions

diff --git a/include/linux/pci.h b/include/linux/pci.h
index ea2a153a9126..6a1800ecd95d 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1261,5 +1261,10 @@ static inline irqreturn_t pci_sriov_migration(struct pci_dev *dev)
 }
 #endif
 
+#if defined(CONFIG_HOTPLUG_PCI) || defined(CONFIG_HOTPLUG_PCI_MODULE)
+extern void pci_hp_create_module_link(struct pci_slot *pci_slot);
+extern void pci_hp_remove_module_link(struct pci_slot *pci_slot);
+#endif
+
 #endif /* __KERNEL__ */
 #endif /* LINUX_PCI_H */
diff --git a/include/linux/pci_hotplug.h b/include/linux/pci_hotplug.h
index 11936fd0b56d..b3646cd7fd5a 100644
--- a/include/linux/pci_hotplug.h
+++ b/include/linux/pci_hotplug.h
@@ -69,6 +69,7 @@ enum pcie_link_speed {
 /**
  * struct hotplug_slot_ops -the callbacks that the hotplug pci core can use
  * @owner: The module owner of this structure
+ * @mod_name: The module name (KBUILD_MODNAME) of this structure
  * @enable_slot: Called when the user wants to enable a specific pci slot
  * @disable_slot: Called when the user wants to disable a specific pci slot
  * @set_attention_status: Called to set the specific slot's attention LED to
@@ -101,6 +102,7 @@ enum pcie_link_speed {
  */
 struct hotplug_slot_ops {
         struct module *owner;
+        const char *mod_name;
         int (*enable_slot)              (struct hotplug_slot *slot);
         int (*disable_slot)             (struct hotplug_slot *slot);
         int (*set_attention_status)     (struct hotplug_slot *slot, u8 value);
@@ -159,12 +161,21 @@ static inline const char *hotplug_slot_name(const struct hotplug_slot *slot)
         return pci_slot_name(slot->pci_slot);
 }
 
-extern int pci_hp_register(struct hotplug_slot *, struct pci_bus *, int nr,
-                           const char *name);
+extern int __pci_hp_register(struct hotplug_slot *slot, struct pci_bus *pbus,
+                             int nr, const char *name,
+                             struct module *owner, const char *mod_name);
 extern int pci_hp_deregister(struct hotplug_slot *slot);
 extern int __must_check pci_hp_change_slot_info (struct hotplug_slot *slot,
                                                  struct hotplug_slot_info *info);
 
+static inline int pci_hp_register(struct hotplug_slot *slot,
+                                  struct pci_bus *pbus,
+                                  int devnr, const char *name)
+{
+        return __pci_hp_register(slot, pbus, devnr, name,
+                                 THIS_MODULE, KBUILD_MODNAME);
+}
+
 /* PCI Setting Record (Type 0) */
 struct hpp_type0 {
         u32 revision;