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// 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, 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, want_memblock);
if (rc)
vmem_remove_mapping(start, size);
return rc;
}
#ifdef CONFIG_MEMORY_HOTREMOVE
int arch_remove_memory(u64 start, u64 size)
{
/*
* 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 */