| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * S390 version |
| * Copyright IBM Corp. 1999 |
| * Author(s): Hartmut Penner (hp@de.ibm.com) |
| * |
| * Derived from "arch/i386/mm/init.c" |
| * Copyright (C) 1995 Linus Torvalds |
| */ |
| |
| #include <linux/signal.h> |
| #include <linux/sched.h> |
| #include <linux/kernel.h> |
| #include <linux/errno.h> |
| #include <linux/string.h> |
| #include <linux/types.h> |
| #include <linux/ptrace.h> |
| #include <linux/mman.h> |
| #include <linux/mm.h> |
| #include <linux/swap.h> |
| #include <linux/smp.h> |
| #include <linux/init.h> |
| #include <linux/pagemap.h> |
| #include <linux/memblock.h> |
| #include <linux/memory.h> |
| #include <linux/pfn.h> |
| #include <linux/poison.h> |
| #include <linux/initrd.h> |
| #include <linux/export.h> |
| #include <linux/cma.h> |
| #include <linux/gfp.h> |
| #include <asm/processor.h> |
| #include <linux/uaccess.h> |
| #include <asm/pgtable.h> |
| #include <asm/pgalloc.h> |
| #include <asm/dma.h> |
| #include <asm/lowcore.h> |
| #include <asm/tlb.h> |
| #include <asm/tlbflush.h> |
| #include <asm/sections.h> |
| #include <asm/ctl_reg.h> |
| #include <asm/sclp.h> |
| #include <asm/set_memory.h> |
| #include <asm/kasan.h> |
| |
| pgd_t swapper_pg_dir[PTRS_PER_PGD] __section(.bss..swapper_pg_dir); |
| |
| unsigned long empty_zero_page, zero_page_mask; |
| EXPORT_SYMBOL(empty_zero_page); |
| EXPORT_SYMBOL(zero_page_mask); |
| |
| static void __init setup_zero_pages(void) |
| { |
| unsigned int order; |
| struct page *page; |
| int i; |
| |
| /* Latest machines require a mapping granularity of 512KB */ |
| order = 7; |
| |
| /* Limit number of empty zero pages for small memory sizes */ |
| while (order > 2 && (totalram_pages() >> 10) < (1UL << order)) |
| order--; |
| |
| empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order); |
| if (!empty_zero_page) |
| panic("Out of memory in setup_zero_pages"); |
| |
| page = virt_to_page((void *) empty_zero_page); |
| split_page(page, order); |
| for (i = 1 << order; i > 0; i--) { |
| mark_page_reserved(page); |
| page++; |
| } |
| |
| zero_page_mask = ((PAGE_SIZE << order) - 1) & PAGE_MASK; |
| } |
| |
| /* |
| * paging_init() sets up the page tables |
| */ |
| void __init paging_init(void) |
| { |
| unsigned long max_zone_pfns[MAX_NR_ZONES]; |
| unsigned long pgd_type, asce_bits; |
| psw_t psw; |
| |
| init_mm.pgd = swapper_pg_dir; |
| if (VMALLOC_END > _REGION2_SIZE) { |
| asce_bits = _ASCE_TYPE_REGION2 | _ASCE_TABLE_LENGTH; |
| pgd_type = _REGION2_ENTRY_EMPTY; |
| } else { |
| asce_bits = _ASCE_TYPE_REGION3 | _ASCE_TABLE_LENGTH; |
| pgd_type = _REGION3_ENTRY_EMPTY; |
| } |
| init_mm.context.asce = (__pa(init_mm.pgd) & PAGE_MASK) | asce_bits; |
| S390_lowcore.kernel_asce = init_mm.context.asce; |
| S390_lowcore.user_asce = S390_lowcore.kernel_asce; |
| crst_table_init((unsigned long *) init_mm.pgd, pgd_type); |
| vmem_map_init(); |
| kasan_copy_shadow(init_mm.pgd); |
| |
| /* enable virtual mapping in kernel mode */ |
| __ctl_load(S390_lowcore.kernel_asce, 1, 1); |
| __ctl_load(S390_lowcore.kernel_asce, 7, 7); |
| __ctl_load(S390_lowcore.kernel_asce, 13, 13); |
| psw.mask = __extract_psw(); |
| psw_bits(psw).dat = 1; |
| psw_bits(psw).as = PSW_BITS_AS_HOME; |
| __load_psw_mask(psw.mask); |
| kasan_free_early_identity(); |
| |
| sparse_memory_present_with_active_regions(MAX_NUMNODES); |
| sparse_init(); |
| memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); |
| max_zone_pfns[ZONE_DMA] = PFN_DOWN(MAX_DMA_ADDRESS); |
| max_zone_pfns[ZONE_NORMAL] = max_low_pfn; |
| free_area_init_nodes(max_zone_pfns); |
| } |
| |
| void mark_rodata_ro(void) |
| { |
| unsigned long size = __end_ro_after_init - __start_ro_after_init; |
| |
| set_memory_ro((unsigned long)__start_ro_after_init, size >> PAGE_SHIFT); |
| pr_info("Write protected read-only-after-init data: %luk\n", size >> 10); |
| } |
| |
| void __init mem_init(void) |
| { |
| cpumask_set_cpu(0, &init_mm.context.cpu_attach_mask); |
| cpumask_set_cpu(0, mm_cpumask(&init_mm)); |
| |
| set_max_mapnr(max_low_pfn); |
| high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); |
| |
| /* Setup guest page hinting */ |
| cmma_init(); |
| |
| /* this will put all low memory onto the freelists */ |
| memblock_free_all(); |
| setup_zero_pages(); /* Setup zeroed pages. */ |
| |
| cmma_init_nodat(); |
| |
| mem_init_print_info(NULL); |
| } |
| |
| void free_initmem(void) |
| { |
| __set_memory((unsigned long)_sinittext, |
| (unsigned long)(_einittext - _sinittext) >> PAGE_SHIFT, |
| SET_MEMORY_RW | SET_MEMORY_NX); |
| free_initmem_default(POISON_FREE_INITMEM); |
| } |
| |
| #ifdef CONFIG_BLK_DEV_INITRD |
| void __init free_initrd_mem(unsigned long start, unsigned long end) |
| { |
| free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM, |
| "initrd"); |
| } |
| #endif |
| |
| unsigned long memory_block_size_bytes(void) |
| { |
| /* |
| * Make sure the memory block size is always greater |
| * or equal than the memory increment size. |
| */ |
| return max_t(unsigned long, MIN_MEMORY_BLOCK_SIZE, sclp.rzm); |
| } |
| |
| #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, struct vmem_altmap *altmap, |
| bool want_memblock) |
| { |
| unsigned long start_pfn = PFN_DOWN(start); |
| unsigned long size_pages = PFN_DOWN(size); |
| int rc; |
| |
| rc = vmem_add_mapping(start, size); |
| if (rc) |
| return rc; |
| |
| rc = __add_pages(nid, start_pfn, size_pages, altmap, want_memblock); |
| if (rc) |
| vmem_remove_mapping(start, size); |
| return rc; |
| } |
| |
| #ifdef CONFIG_MEMORY_HOTREMOVE |
| int arch_remove_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap) |
| { |
| /* |
| * There is no hardware or firmware interface which could trigger a |
| * hot memory remove on s390. So there is nothing that needs to be |
| * implemented. |
| */ |
| return -EBUSY; |
| } |
| #endif |
| #endif /* CONFIG_MEMORY_HOTPLUG */ |