1 files changed, 48 insertions, 0 deletions

diff --git a/drivers/infiniband/hw/ehca/ehca_main.c b/drivers/infiniband/hw/ehca/ehca_main.c
index 086959a0cbee..bb02a86aa526 100644
--- a/drivers/infiniband/hw/ehca/ehca_main.c
+++ b/drivers/infiniband/hw/ehca/ehca_main.c
@@ -44,6 +44,8 @@
 #include <linux/slab.h>
 #endif
 
+#include <linux/notifier.h>
+#include <linux/memory.h>
 #include "ehca_classes.h"
 #include "ehca_iverbs.h"
 #include "ehca_mrmw.h"
@@ -969,6 +971,41 @@ void ehca_poll_eqs(unsigned long data)
         spin_unlock(&shca_list_lock);
 }
 
+static int ehca_mem_notifier(struct notifier_block *nb,
+                             unsigned long action, void *data)
+{
+        static unsigned long ehca_dmem_warn_time;
+
+        switch (action) {
+        case MEM_CANCEL_OFFLINE:
+        case MEM_CANCEL_ONLINE:
+        case MEM_ONLINE:
+        case MEM_OFFLINE:
+                return NOTIFY_OK;
+        case MEM_GOING_ONLINE:
+        case MEM_GOING_OFFLINE:
+                /* only ok if no hca is attached to the lpar */
+                spin_lock(&shca_list_lock);
+                if (list_empty(&shca_list)) {
+                        spin_unlock(&shca_list_lock);
+                        return NOTIFY_OK;
+                } else {
+                        spin_unlock(&shca_list_lock);
+                        if (printk_timed_ratelimit(&ehca_dmem_warn_time,
+                                                   30 * 1000))
+                                ehca_gen_err("DMEM operations are not allowed"
+                                             "as long as an ehca adapter is"
+                                             "attached to the LPAR");
+                        return NOTIFY_BAD;
+                }
+        }
+        return NOTIFY_OK;
+}
+
+static struct notifier_block ehca_mem_nb = {
+        .notifier_call = ehca_mem_notifier,
+};
+
 static int __init ehca_module_init(void)
 {
         int ret;
@@ -996,6 +1033,12 @@ static int __init ehca_module_init(void)
                 goto module_init2;
         }
 
+        ret = register_memory_notifier(&ehca_mem_nb);
+        if (ret) {
+                ehca_gen_err("Failed registering memory add/remove notifier");
+                goto module_init3;
+        }
+
         if (ehca_poll_all_eqs != 1) {
                 ehca_gen_err("WARNING!!!");
                 ehca_gen_err("It is possible to lose interrupts.");
@@ -1008,6 +1051,9 @@ static int __init ehca_module_init(void)
 
         return 0;
 
+module_init3:
+        ibmebus_unregister_driver(&ehca_driver);
+
 module_init2:
         ehca_destroy_slab_caches();
 
@@ -1023,6 +1069,8 @@ static void __exit ehca_module_exit(void)
 
         ibmebus_unregister_driver(&ehca_driver);
 
+        unregister_memory_notifier(&ehca_mem_nb);
+
         ehca_destroy_slab_caches();
 
         ehca_destroy_comp_pool();