md/raid5: Fix CPU hotplug callback registration

[pandora-kernel.git] / drivers / md / raid5.c

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index c7109c8..7c963c4 100644 (file)
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -4450,23 +4450,43 @@ raid5_size(struct mddev *mddev, sector_t sectors, int raid_disks)
        return sectors * (raid_disks - conf->max_degraded);
 }
 
+static void free_scratch_buffer(struct r5conf *conf, struct raid5_percpu *percpu)
+{
+       safe_put_page(percpu->spare_page);
+       kfree(percpu->scribble);
+       percpu->spare_page = NULL;
+       percpu->scribble = NULL;
+}
+
+static int alloc_scratch_buffer(struct r5conf *conf, struct raid5_percpu *percpu)
+{
+       if (conf->level == 6 && !percpu->spare_page)
+               percpu->spare_page = alloc_page(GFP_KERNEL);
+       if (!percpu->scribble)
+               percpu->scribble = kmalloc(conf->scribble_len, GFP_KERNEL);
+
+       if (!percpu->scribble || (conf->level == 6 && !percpu->spare_page)) {
+               free_scratch_buffer(conf, percpu);
+               return -ENOMEM;
+       }
+
+       return 0;
+}
+
 static void raid5_free_percpu(struct r5conf *conf)
 {
-       struct raid5_percpu *percpu;
        unsigned long cpu;
 
        if (!conf->percpu)
                return;
 
-       get_online_cpus();
-       for_each_possible_cpu(cpu) {
-               percpu = per_cpu_ptr(conf->percpu, cpu);
-               safe_put_page(percpu->spare_page);
-               kfree(percpu->scribble);
-       }
 #ifdef CONFIG_HOTPLUG_CPU
        unregister_cpu_notifier(&conf->cpu_notify);
 #endif
+
+       get_online_cpus();
+       for_each_possible_cpu(cpu)
+               free_scratch_buffer(conf, per_cpu_ptr(conf->percpu, cpu));
        put_online_cpus();
 
        free_percpu(conf->percpu);
@@ -4492,15 +4512,7 @@ static int raid456_cpu_notify(struct notifier_block *nfb, unsigned long action,
        switch (action) {
        case CPU_UP_PREPARE:
        case CPU_UP_PREPARE_FROZEN:
-               if (conf->level == 6 && !percpu->spare_page)
-                       percpu->spare_page = alloc_page(GFP_KERNEL);
-               if (!percpu->scribble)
-                       percpu->scribble = kmalloc(conf->scribble_len, GFP_KERNEL);
-
-               if (!percpu->scribble ||
-                   (conf->level == 6 && !percpu->spare_page)) {
-                       safe_put_page(percpu->spare_page);
-                       kfree(percpu->scribble);
+               if (alloc_scratch_buffer(conf, percpu)) {
                        pr_err("%s: failed memory allocation for cpu%ld\n",
                               __func__, cpu);
                        return notifier_from_errno(-ENOMEM);
@@ -4508,10 +4520,7 @@ static int raid456_cpu_notify(struct notifier_block *nfb, unsigned long action,
                break;
        case CPU_DEAD:
        case CPU_DEAD_FROZEN:
-               safe_put_page(percpu->spare_page);
-               kfree(percpu->scribble);
-               percpu->spare_page = NULL;
-               percpu->scribble = NULL;
+               free_scratch_buffer(conf, per_cpu_ptr(conf->percpu, cpu));
                break;
        default:
                break;
@@ -4523,40 +4532,29 @@ static int raid456_cpu_notify(struct notifier_block *nfb, unsigned long action,
 static int raid5_alloc_percpu(struct r5conf *conf)
 {
        unsigned long cpu;
-       struct page *spare_page;
-       struct raid5_percpu __percpu *allcpus;
-       void *scribble;
-       int err;
+       int err = 0;
 
-       allcpus = alloc_percpu(struct raid5_percpu);
-       if (!allcpus)
+       conf->percpu = alloc_percpu(struct raid5_percpu);
+       if (!conf->percpu)
                return -ENOMEM;
-       conf->percpu = allcpus;
+
+#ifdef CONFIG_HOTPLUG_CPU
+       conf->cpu_notify.notifier_call = raid456_cpu_notify;
+       conf->cpu_notify.priority = 0;
+       err = register_cpu_notifier(&conf->cpu_notify);
+       if (err)
+               return err;
+#endif
 
        get_online_cpus();
-       err = 0;
        for_each_present_cpu(cpu) {
-               if (conf->level == 6) {
-                       spare_page = alloc_page(GFP_KERNEL);
-                       if (!spare_page) {
-                               err = -ENOMEM;
-                               break;
-                       }
-                       per_cpu_ptr(conf->percpu, cpu)->spare_page = spare_page;
-               }
-               scribble = kmalloc(conf->scribble_len, GFP_KERNEL);
-               if (!scribble) {
-                       err = -ENOMEM;
+               err = alloc_scratch_buffer(conf, per_cpu_ptr(conf->percpu, cpu));
+               if (err) {
+                       pr_err("%s: failed memory allocation for cpu%ld\n",
+                              __func__, cpu);
                        break;
                }
-               per_cpu_ptr(conf->percpu, cpu)->scribble = scribble;
        }
-#ifdef CONFIG_HOTPLUG_CPU
-       conf->cpu_notify.notifier_call = raid456_cpu_notify;
-       conf->cpu_notify.priority = 0;
-       if (err == 0)
-               err = register_cpu_notifier(&conf->cpu_notify);
-#endif
        put_online_cpus();
 
        return err;