diff options
-rw-r--r-- | drivers/hv/hv_balloon.c | 68 |
1 files changed, 63 insertions, 5 deletions
diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c index 9cbbb831778a..8e30415b0eb7 100644 --- a/drivers/hv/hv_balloon.c +++ b/drivers/hv/hv_balloon.c @@ -533,6 +533,9 @@ struct hv_dynmem_device { */ struct task_struct *thread; + struct mutex ha_region_mutex; + struct completion waiter_event; + /* * A list of hot-add regions. */ @@ -549,7 +552,59 @@ struct hv_dynmem_device { static struct hv_dynmem_device dm_device; static void post_status(struct hv_dynmem_device *dm); + #ifdef CONFIG_MEMORY_HOTPLUG +static void acquire_region_mutex(bool trylock) +{ + if (trylock) { + reinit_completion(&dm_device.waiter_event); + while (!mutex_trylock(&dm_device.ha_region_mutex)) + wait_for_completion(&dm_device.waiter_event); + } else { + mutex_lock(&dm_device.ha_region_mutex); + } +} + +static void release_region_mutex(bool trylock) +{ + if (trylock) { + mutex_unlock(&dm_device.ha_region_mutex); + } else { + mutex_unlock(&dm_device.ha_region_mutex); + complete(&dm_device.waiter_event); + } +} + +static int hv_memory_notifier(struct notifier_block *nb, unsigned long val, + void *v) +{ + switch (val) { + case MEM_GOING_ONLINE: + acquire_region_mutex(true); + break; + + case MEM_ONLINE: + case MEM_CANCEL_ONLINE: + release_region_mutex(true); + if (dm_device.ha_waiting) { + dm_device.ha_waiting = false; + complete(&dm_device.ol_waitevent); + } + break; + + case MEM_GOING_OFFLINE: + case MEM_OFFLINE: + case MEM_CANCEL_OFFLINE: + break; + } + return NOTIFY_OK; +} + +static struct notifier_block hv_memory_nb = { + .notifier_call = hv_memory_notifier, + .priority = 0 +}; + static void hv_bring_pgs_online(unsigned long start_pfn, unsigned long size) { @@ -591,6 +646,7 @@ static void hv_mem_hot_add(unsigned long start, unsigned long size, init_completion(&dm_device.ol_waitevent); dm_device.ha_waiting = true; + release_region_mutex(false); nid = memory_add_physaddr_to_nid(PFN_PHYS(start_pfn)); ret = add_memory(nid, PFN_PHYS((start_pfn)), (HA_CHUNK << PAGE_SHIFT)); @@ -619,6 +675,7 @@ static void hv_mem_hot_add(unsigned long start, unsigned long size, * have not been "onlined" within the allowed time. */ wait_for_completion_timeout(&dm_device.ol_waitevent, 5*HZ); + acquire_region_mutex(false); post_status(&dm_device); } @@ -632,11 +689,6 @@ static void hv_online_page(struct page *pg) unsigned long cur_start_pgp; unsigned long cur_end_pgp; - if (dm_device.ha_waiting) { - dm_device.ha_waiting = false; - complete(&dm_device.ol_waitevent); - } - list_for_each(cur, &dm_device.ha_region_list) { has = list_entry(cur, struct hv_hotadd_state, list); cur_start_pgp = (unsigned long) @@ -834,6 +886,7 @@ static void hot_add_req(struct work_struct *dummy) resp.hdr.size = sizeof(struct dm_hot_add_response); #ifdef CONFIG_MEMORY_HOTPLUG + acquire_region_mutex(false); pg_start = dm->ha_wrk.ha_page_range.finfo.start_page; pfn_cnt = dm->ha_wrk.ha_page_range.finfo.page_cnt; @@ -865,6 +918,7 @@ 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); + release_region_mutex(false); #endif /* * The result field of the response structure has the @@ -1388,7 +1442,9 @@ static int balloon_probe(struct hv_device *dev, dm_device.next_version = DYNMEM_PROTOCOL_VERSION_WIN7; init_completion(&dm_device.host_event); init_completion(&dm_device.config_event); + init_completion(&dm_device.waiter_event); INIT_LIST_HEAD(&dm_device.ha_region_list); + mutex_init(&dm_device.ha_region_mutex); INIT_WORK(&dm_device.balloon_wrk.wrk, balloon_up); INIT_WORK(&dm_device.ha_wrk.wrk, hot_add_req); dm_device.host_specified_ha_region = false; @@ -1402,6 +1458,7 @@ static int balloon_probe(struct hv_device *dev, #ifdef CONFIG_MEMORY_HOTPLUG set_online_page_callback(&hv_online_page); + register_memory_notifier(&hv_memory_nb); #endif hv_set_drvdata(dev, &dm_device); @@ -1520,6 +1577,7 @@ static int balloon_remove(struct hv_device *dev) kfree(send_buffer); #ifdef CONFIG_MEMORY_HOTPLUG restore_online_page_callback(&hv_online_page); + unregister_memory_notifier(&hv_memory_nb); #endif list_for_each_safe(cur, tmp, &dm->ha_region_list) { has = list_entry(cur, struct hv_hotadd_state, list); |