diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c index c52a6b834f08ada83a23b2a04bd07ee508ca0f72..3b567838b905f99ff8a755a90647520ba9348d00 100644 --- a/arch/s390/mm/init.c +++ b/arch/s390/mm/init.c @@ -26,6 +26,7 @@ #include #include #include +#include #include #include #include @@ -167,6 +168,58 @@ unsigned long memory_block_size_bytes(void) } #ifdef CONFIG_MEMORY_HOTPLUG + +#ifdef CONFIG_CMA + +/* Prevent memory blocks which contain cma regions from going offline */ + +struct s390_cma_mem_data { + unsigned long start; + unsigned long end; +}; + +static int s390_cma_check_range(struct cma *cma, void *data) +{ + struct s390_cma_mem_data *mem_data; + unsigned long start, end; + + mem_data = data; + start = cma_get_base(cma); + end = start + cma_get_size(cma); + if (end < mem_data->start) + return 0; + if (start >= mem_data->end) + return 0; + return -EBUSY; +} + +static int s390_cma_mem_notifier(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct s390_cma_mem_data mem_data; + struct memory_notify *arg; + int rc = 0; + + arg = data; + mem_data.start = arg->start_pfn << PAGE_SHIFT; + mem_data.end = mem_data.start + (arg->nr_pages << PAGE_SHIFT); + if (action == MEM_GOING_OFFLINE) + rc = cma_for_each_area(s390_cma_check_range, &mem_data); + return notifier_from_errno(rc); +} + +static struct notifier_block s390_cma_mem_nb = { + .notifier_call = s390_cma_mem_notifier, +}; + +static int __init s390_cma_mem_init(void) +{ + return register_memory_notifier(&s390_cma_mem_nb); +} +device_initcall(s390_cma_mem_init); + +#endif /* CONFIG_CMA */ + int arch_add_memory(int nid, u64 start, u64 size, bool want_memblock) { unsigned long start_pfn = PFN_DOWN(start);