1 // SPDX-License-Identifier: GPL-2.0
4 * Copyright IBM Corp. 1999
5 * Author(s): Hartmut Penner (hp@de.ibm.com)
7 * Derived from "arch/i386/mm/init.c"
8 * Copyright (C) 1995 Linus Torvalds
11 #include <linux/signal.h>
12 #include <linux/sched.h>
13 #include <linux/kernel.h>
14 #include <linux/errno.h>
15 #include <linux/string.h>
16 #include <linux/types.h>
17 #include <linux/ptrace.h>
18 #include <linux/mman.h>
20 #include <linux/swap.h>
21 #include <linux/swiotlb.h>
22 #include <linux/smp.h>
23 #include <linux/init.h>
24 #include <linux/pagemap.h>
25 #include <linux/memblock.h>
26 #include <linux/memory.h>
27 #include <linux/pfn.h>
28 #include <linux/poison.h>
29 #include <linux/initrd.h>
30 #include <linux/export.h>
31 #include <linux/cma.h>
32 #include <linux/gfp.h>
33 #include <linux/dma-direct.h>
34 #include <linux/percpu.h>
35 #include <asm/processor.h>
36 #include <linux/uaccess.h>
37 #include <asm/pgalloc.h>
38 #include <asm/ctlreg.h>
39 #include <asm/kfence.h>
40 #include <asm/ptdump.h>
42 #include <asm/abs_lowcore.h>
44 #include <asm/tlbflush.h>
45 #include <asm/sections.h>
47 #include <asm/set_memory.h>
48 #include <asm/kasan.h>
49 #include <asm/dma-mapping.h>
51 #include <linux/virtio_anchor.h>
52 #include <linux/virtio_config.h>
54 pgd_t swapper_pg_dir[PTRS_PER_PGD] __section(".bss..swapper_pg_dir");
55 pgd_t invalid_pg_dir[PTRS_PER_PGD] __section(".bss..invalid_pg_dir");
57 struct ctlreg __bootdata_preserved(s390_invalid_asce);
59 unsigned long empty_zero_page, zero_page_mask;
60 EXPORT_SYMBOL(empty_zero_page);
61 EXPORT_SYMBOL(zero_page_mask);
63 static void __init setup_zero_pages(void)
69 /* Latest machines require a mapping granularity of 512KB */
72 /* Limit number of empty zero pages for small memory sizes */
73 while (order > 2 && (totalram_pages() >> 10) < (1UL << order))
76 empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order);
78 panic("Out of memory in setup_zero_pages");
80 page = virt_to_page((void *) empty_zero_page);
81 split_page(page, order);
82 for (i = 1 << order; i > 0; i--) {
83 mark_page_reserved(page);
87 zero_page_mask = ((PAGE_SIZE << order) - 1) & PAGE_MASK;
91 * paging_init() sets up the page tables
93 void __init paging_init(void)
95 unsigned long max_zone_pfns[MAX_NR_ZONES];
100 memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
101 max_zone_pfns[ZONE_DMA] = virt_to_pfn(MAX_DMA_ADDRESS);
102 max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
103 free_area_init(max_zone_pfns);
106 void mark_rodata_ro(void)
108 unsigned long size = __end_ro_after_init - __start_ro_after_init;
110 __set_memory_ro(__start_ro_after_init, __end_ro_after_init);
111 pr_info("Write protected read-only-after-init data: %luk\n", size >> 10);
115 int set_memory_encrypted(unsigned long vaddr, int numpages)
119 /* make specified pages unshared, (swiotlb, dma_free) */
120 for (i = 0; i < numpages; ++i) {
121 uv_remove_shared(virt_to_phys((void *)vaddr));
127 int set_memory_decrypted(unsigned long vaddr, int numpages)
130 /* make specified pages shared (swiotlb, dma_alloca) */
131 for (i = 0; i < numpages; ++i) {
132 uv_set_shared(virt_to_phys((void *)vaddr));
138 /* are we a protected virtualization guest? */
139 bool force_dma_unencrypted(struct device *dev)
141 return is_prot_virt_guest();
144 /* protected virtualization */
145 static void pv_init(void)
147 if (!is_prot_virt_guest())
150 virtio_set_mem_acc_cb(virtio_require_restricted_mem_acc);
152 /* make sure bounce buffers are shared */
153 swiotlb_init(true, SWIOTLB_FORCE | SWIOTLB_VERBOSE);
154 swiotlb_update_mem_attributes();
157 void __init mem_init(void)
159 cpumask_set_cpu(0, &init_mm.context.cpu_attach_mask);
160 cpumask_set_cpu(0, mm_cpumask(&init_mm));
162 set_max_mapnr(max_low_pfn);
163 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
166 kfence_split_mapping();
168 /* this will put all low memory onto the freelists */
170 setup_zero_pages(); /* Setup zeroed pages. */
173 void free_initmem(void)
175 set_memory_rwnx((unsigned long)_sinittext,
176 (unsigned long)(_einittext - _sinittext) >> PAGE_SHIFT);
177 free_initmem_default(POISON_FREE_INITMEM);
180 unsigned long memory_block_size_bytes(void)
183 * Make sure the memory block size is always greater
184 * or equal than the memory increment size.
186 return max_t(unsigned long, MIN_MEMORY_BLOCK_SIZE, sclp.rzm);
189 unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
190 EXPORT_SYMBOL(__per_cpu_offset);
192 static int __init pcpu_cpu_distance(unsigned int from, unsigned int to)
194 return LOCAL_DISTANCE;
197 static int __init pcpu_cpu_to_node(int cpu)
202 void __init setup_per_cpu_areas(void)
209 * Always reserve area for module percpu variables. That's
210 * what the legacy allocator did.
212 rc = pcpu_embed_first_chunk(PERCPU_MODULE_RESERVE,
213 PERCPU_DYNAMIC_RESERVE, PAGE_SIZE,
217 panic("Failed to initialize percpu areas.");
219 delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
220 for_each_possible_cpu(cpu)
221 __per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu];
224 #ifdef CONFIG_MEMORY_HOTPLUG
228 /* Prevent memory blocks which contain cma regions from going offline */
230 struct s390_cma_mem_data {
235 static int s390_cma_check_range(struct cma *cma, void *data)
237 struct s390_cma_mem_data *mem_data;
238 unsigned long start, end;
241 start = cma_get_base(cma);
242 end = start + cma_get_size(cma);
243 if (end < mem_data->start)
245 if (start >= mem_data->end)
250 static int s390_cma_mem_notifier(struct notifier_block *nb,
251 unsigned long action, void *data)
253 struct s390_cma_mem_data mem_data;
254 struct memory_notify *arg;
258 mem_data.start = arg->start_pfn << PAGE_SHIFT;
259 mem_data.end = mem_data.start + (arg->nr_pages << PAGE_SHIFT);
260 if (action == MEM_GOING_OFFLINE)
261 rc = cma_for_each_area(s390_cma_check_range, &mem_data);
262 return notifier_from_errno(rc);
265 static struct notifier_block s390_cma_mem_nb = {
266 .notifier_call = s390_cma_mem_notifier,
269 static int __init s390_cma_mem_init(void)
271 return register_memory_notifier(&s390_cma_mem_nb);
273 device_initcall(s390_cma_mem_init);
275 #endif /* CONFIG_CMA */
277 int arch_add_memory(int nid, u64 start, u64 size,
278 struct mhp_params *params)
280 unsigned long start_pfn = PFN_DOWN(start);
281 unsigned long size_pages = PFN_DOWN(size);
284 if (WARN_ON_ONCE(params->altmap))
287 if (WARN_ON_ONCE(params->pgprot.pgprot != PAGE_KERNEL.pgprot))
290 VM_BUG_ON(!mhp_range_allowed(start, size, true));
291 rc = vmem_add_mapping(start, size);
295 rc = __add_pages(nid, start_pfn, size_pages, params);
297 vmem_remove_mapping(start, size);
301 void arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
303 unsigned long start_pfn = start >> PAGE_SHIFT;
304 unsigned long nr_pages = size >> PAGE_SHIFT;
306 __remove_pages(start_pfn, nr_pages, altmap);
307 vmem_remove_mapping(start, size);
309 #endif /* CONFIG_MEMORY_HOTPLUG */