Drivers: hv: hv_balloon: report offline pages as being used

[firefly-linux-kernel-4.4.55.git] / drivers / hv / hv_balloon.c

diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c
index ea3d33cdf99c331592e675d2ba2e3446ec2dcf9c..53932b3e197396900aed3eb9999ee1e4e865f7ce 100644 (file)
--- a/drivers/hv/hv_balloon.c
+++ b/drivers/hv/hv_balloon.c
@@ -503,6 +503,8 @@ struct hv_dynmem_device {
         * Number of pages we have currently ballooned out.
         */
        unsigned int num_pages_ballooned;
+       unsigned int num_pages_onlined;
+       unsigned int num_pages_added;
 
        /*
         * State to manage the ballooning (up) operation.
@@ -556,12 +558,15 @@ static void post_status(struct hv_dynmem_device *dm);
 static int hv_memory_notifier(struct notifier_block *nb, unsigned long val,
                              void *v)
 {
+       struct memory_notify *mem = (struct memory_notify *)v;
+
        switch (val) {
        case MEM_GOING_ONLINE:
                mutex_lock(&dm_device.ha_region_mutex);
                break;
 
        case MEM_ONLINE:
+               dm_device.num_pages_onlined += mem->nr_pages;
        case MEM_CANCEL_ONLINE:
                mutex_unlock(&dm_device.ha_region_mutex);
                if (dm_device.ha_waiting) {
@@ -570,8 +575,12 @@ static int hv_memory_notifier(struct notifier_block *nb, unsigned long val,
                }
                break;
 
-       case MEM_GOING_OFFLINE:
        case MEM_OFFLINE:
+               mutex_lock(&dm_device.ha_region_mutex);
+               dm_device.num_pages_onlined -= mem->nr_pages;
+               mutex_unlock(&dm_device.ha_region_mutex);
+               break;
+       case MEM_GOING_OFFLINE:
        case MEM_CANCEL_OFFLINE:
                break;
        }
@@ -896,6 +905,8 @@ static void hot_add_req(struct work_struct *dummy)
        if (do_hot_add)
                resp.page_count = process_hot_add(pg_start, pfn_cnt,
                                                rg_start, rg_sz);
+
+       dm->num_pages_added += resp.page_count;
        mutex_unlock(&dm_device.ha_region_mutex);
 #endif
        /*
@@ -1009,17 +1020,21 @@ static void post_status(struct hv_dynmem_device *dm)
        status.hdr.trans_id = atomic_inc_return(&trans_id);
 
        /*
-        * The host expects the guest to report free memory.
-        * Further, the host expects the pressure information to
-        * include the ballooned out pages.
-        * For a given amount of memory that we are managing, we
-        * need to compute a floor below which we should not balloon.
-        * Compute this and add it to the pressure report.
+        * The host expects the guest to report free and committed memory.
+        * Furthermore, the host expects the pressure information to include
+        * the ballooned out pages. For a given amount of memory that we are
+        * managing we need to compute a floor below which we should not
+        * balloon. Compute this and add it to the pressure report.
+        * We also need to report all offline pages (num_pages_added -
+        * num_pages_onlined) as committed to the host, otherwise it can try
+        * asking us to balloon them out.
         */
        status.num_avail = val.freeram;
        status.num_committed = vm_memory_committed() +
-                               dm->num_pages_ballooned +
-                               compute_balloon_floor();
+               dm->num_pages_ballooned +
+               (dm->num_pages_added > dm->num_pages_onlined ?
+                dm->num_pages_added - dm->num_pages_onlined : 0) +
+               compute_balloon_floor();
 
        /*
         * If our transaction ID is no longer current, just don't