diff options
Diffstat (limited to 'arch/s390/mm/init.c')
| -rw-r--r-- | arch/s390/mm/init.c | 251 |
1 files changed, 251 insertions, 0 deletions
diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c new file mode 100644 index 000000000..379a925d9 --- /dev/null +++ b/arch/s390/mm/init.c @@ -0,0 +1,251 @@ +// 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; +} + +void arch_remove_memory(int nid, u64 start, u64 size, + struct vmem_altmap *altmap) +{ + unsigned long start_pfn = start >> PAGE_SHIFT; + unsigned long nr_pages = size >> PAGE_SHIFT; + + __remove_pages(start_pfn, nr_pages, altmap); + vmem_remove_mapping(start, size); +} +#endif /* CONFIG_MEMORY_HOTPLUG */ |