powerpc/pseries: Introduce pSeries_reconfig_notify()

This introduces pSeries_reconfig_notify() as a just wrapper of
blocking_notifier_call_chain() for pSeries_reconfig_chain.

This is a preparation to improvement of error code on reconfiguration
notifier failure.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

3 files changed, 23 insertions, 19 deletions

diff --git a/arch/powerpc/include/asm/pSeries_reconfig.h b/arch/powerpc/include/asm/pSeries_reconfig.h
index 89d2f99c1bf4..23cd6cc30bcf 100644
--- a/arch/powerpc/include/asm/pSeries_reconfig.h
+++ b/arch/powerpc/include/asm/pSeries_reconfig.h
@@ -17,7 +17,7 @@
 #ifdef CONFIG_PPC_PSERIES
 extern int pSeries_reconfig_notifier_register(struct notifier_block *);
 extern void pSeries_reconfig_notifier_unregister(struct notifier_block *);
-extern struct blocking_notifier_head pSeries_reconfig_chain;
+extern int pSeries_reconfig_notify(unsigned long action, void *p);
 /* Not the best place to put this, will be fixed when we move some
  * of the rtas suspend-me stuff to pseries */
 extern void pSeries_coalesce_init(void);
diff --git a/arch/powerpc/platforms/pseries/dlpar.c b/arch/powerpc/platforms/pseries/dlpar.c
index 57ceb92b2288..e9be25bc571b 100644
--- a/arch/powerpc/platforms/pseries/dlpar.c
+++ b/arch/powerpc/platforms/pseries/dlpar.c
@@ -262,12 +262,11 @@ int dlpar_attach_node(struct device_node *dn)
         if (!dn->parent)
                 return -ENOMEM;
 
-        rc = blocking_notifier_call_chain(&pSeries_reconfig_chain,
-                                          PSERIES_RECONFIG_ADD, dn);
-        if (rc == NOTIFY_BAD) {
+        rc = pSeries_reconfig_notify(PSERIES_RECONFIG_ADD, dn);
+        if (rc) {
                 printk(KERN_ERR "Failed to add device node %s\n",
                        dn->full_name);
-                return -ENOMEM; /* For now, safe to assume kmalloc failure */
+                return rc;
         }
 
         of_attach_node(dn);
@@ -297,8 +296,7 @@ int dlpar_detach_node(struct device_node *dn)
                 remove_proc_entry(dn->pde->name, parent->pde);
 #endif
 
-        blocking_notifier_call_chain(&pSeries_reconfig_chain,
-                            PSERIES_RECONFIG_REMOVE, dn);
+        pSeries_reconfig_notify(PSERIES_RECONFIG_REMOVE, dn);
         of_detach_node(dn);
         of_node_put(dn); /* Must decrement the refcount */
 
diff --git a/arch/powerpc/platforms/pseries/reconfig.c b/arch/powerpc/platforms/pseries/reconfig.c
index 1de2cbb92303..286b6af3d55d 100644
--- a/arch/powerpc/platforms/pseries/reconfig.c
+++ b/arch/powerpc/platforms/pseries/reconfig.c
@@ -97,7 +97,7 @@ static struct device_node *derive_parent(const char *path)
         return parent;
 }
 
-BLOCKING_NOTIFIER_HEAD(pSeries_reconfig_chain);
+static BLOCKING_NOTIFIER_HEAD(pSeries_reconfig_chain);
 
 int pSeries_reconfig_notifier_register(struct notifier_block *nb)
 {
@@ -109,6 +109,16 @@ void pSeries_reconfig_notifier_unregister(struct notifier_block *nb)
         blocking_notifier_chain_unregister(&pSeries_reconfig_chain, nb);
 }
 
+int pSeries_reconfig_notify(unsigned long action, void *p)
+{
+        int err = blocking_notifier_call_chain(&pSeries_reconfig_chain,
+                                                action, p);
+
+        if (err == NOTIFY_BAD)
+                return -ENOMEM; /* For now, safe to assume kmalloc failure */
+        return 0;
+}
+
 static int pSeries_reconfig_add_node(const char *path, struct property *proplist)
 {
         struct device_node *np;
@@ -132,11 +142,9 @@ static int pSeries_reconfig_add_node(const char *path, struct property *proplist
                 goto out_err;
         }
 
-        err = blocking_notifier_call_chain(&pSeries_reconfig_chain,
-                                  PSERIES_RECONFIG_ADD, np);
-        if (err == NOTIFY_BAD) {
+        err = pSeries_reconfig_notify(PSERIES_RECONFIG_ADD, np);
+        if (err) {
                 printk(KERN_ERR "Failed to add device node %s\n", path);
-                err = -ENOMEM; /* For now, safe to assume kmalloc failure */
                 goto out_err;
         }
 
@@ -173,8 +181,7 @@ static int pSeries_reconfig_remove_node(struct device_node *np)
 
         remove_node_proc_entries(np);
 
-        blocking_notifier_call_chain(&pSeries_reconfig_chain,
-                            PSERIES_RECONFIG_REMOVE, np);
+        pSeries_reconfig_notify(PSERIES_RECONFIG_REMOVE, np);
         of_detach_node(np);
 
         of_node_put(parent);
@@ -472,11 +479,10 @@ static int do_update_property(char *buf, size_t bufsize)
                 else
                         action = PSERIES_DRCONF_MEM_REMOVE;
 
-                rc = blocking_notifier_call_chain(&pSeries_reconfig_chain,
-                                                  action, value);
-                if (rc == NOTIFY_BAD) {
-                        rc = prom_update_property(np, oldprop, newprop);
-                        return -ENOMEM;
+                rc = pSeries_reconfig_notify(action, value);
+                if (rc) {
+                        prom_update_property(np, oldprop, newprop);
+                        return rc;
                 }
         }