// 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/bootmem.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 <linux/memblock.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> 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(); /* 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); 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 */ free_all_bootmem(); 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(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 */