1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * S390 version 4 * Copyright IBM Corp. 1999 5 * Author(s): Hartmut Penner (hp@de.ibm.com) 6 * 7 * Derived from "arch/i386/mm/init.c" 8 * Copyright (C) 1995 Linus Torvalds 9 */ 10 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> 19 #include <linux/mm.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 <asm/processor.h> 35 #include <linux/uaccess.h> 36 #include <asm/pgtable.h> 37 #include <asm/pgalloc.h> 38 #include <asm/dma.h> 39 #include <asm/lowcore.h> 40 #include <asm/tlb.h> 41 #include <asm/tlbflush.h> 42 #include <asm/sections.h> 43 #include <asm/ctl_reg.h> 44 #include <asm/sclp.h> 45 #include <asm/set_memory.h> 46 #include <asm/kasan.h> 47 #include <asm/dma-mapping.h> 48 #include <asm/uv.h> 49 50 pgd_t swapper_pg_dir[PTRS_PER_PGD] __section(.bss..swapper_pg_dir); 51 52 unsigned long empty_zero_page, zero_page_mask; 53 EXPORT_SYMBOL(empty_zero_page); 54 EXPORT_SYMBOL(zero_page_mask); 55 56 bool initmem_freed; 57 58 static void __init setup_zero_pages(void) 59 { 60 unsigned int order; 61 struct page *page; 62 int i; 63 64 /* Latest machines require a mapping granularity of 512KB */ 65 order = 7; 66 67 /* Limit number of empty zero pages for small memory sizes */ 68 while (order > 2 && (totalram_pages() >> 10) < (1UL << order)) 69 order--; 70 71 empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order); 72 if (!empty_zero_page) 73 panic("Out of memory in setup_zero_pages"); 74 75 page = virt_to_page((void *) empty_zero_page); 76 split_page(page, order); 77 for (i = 1 << order; i > 0; i--) { 78 mark_page_reserved(page); 79 page++; 80 } 81 82 zero_page_mask = ((PAGE_SIZE << order) - 1) & PAGE_MASK; 83 } 84 85 /* 86 * paging_init() sets up the page tables 87 */ 88 void __init paging_init(void) 89 { 90 unsigned long max_zone_pfns[MAX_NR_ZONES]; 91 unsigned long pgd_type, asce_bits; 92 psw_t psw; 93 94 init_mm.pgd = swapper_pg_dir; 95 if (VMALLOC_END > _REGION2_SIZE) { 96 asce_bits = _ASCE_TYPE_REGION2 | _ASCE_TABLE_LENGTH; 97 pgd_type = _REGION2_ENTRY_EMPTY; 98 } else { 99 asce_bits = _ASCE_TYPE_REGION3 | _ASCE_TABLE_LENGTH; 100 pgd_type = _REGION3_ENTRY_EMPTY; 101 } 102 init_mm.context.asce = (__pa(init_mm.pgd) & PAGE_MASK) | asce_bits; 103 S390_lowcore.kernel_asce = init_mm.context.asce; 104 S390_lowcore.user_asce = S390_lowcore.kernel_asce; 105 crst_table_init((unsigned long *) init_mm.pgd, pgd_type); 106 vmem_map_init(); 107 kasan_copy_shadow(init_mm.pgd); 108 109 /* enable virtual mapping in kernel mode */ 110 __ctl_load(S390_lowcore.kernel_asce, 1, 1); 111 __ctl_load(S390_lowcore.kernel_asce, 7, 7); 112 __ctl_load(S390_lowcore.kernel_asce, 13, 13); 113 psw.mask = __extract_psw(); 114 psw_bits(psw).dat = 1; 115 psw_bits(psw).as = PSW_BITS_AS_HOME; 116 __load_psw_mask(psw.mask); 117 kasan_free_early_identity(); 118 119 sparse_memory_present_with_active_regions(MAX_NUMNODES); 120 sparse_init(); 121 memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); 122 max_zone_pfns[ZONE_DMA] = PFN_DOWN(MAX_DMA_ADDRESS); 123 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 124 free_area_init_nodes(max_zone_pfns); 125 } 126 127 void mark_rodata_ro(void) 128 { 129 unsigned long size = __end_ro_after_init - __start_ro_after_init; 130 131 set_memory_ro((unsigned long)__start_ro_after_init, size >> PAGE_SHIFT); 132 pr_info("Write protected read-only-after-init data: %luk\n", size >> 10); 133 } 134 135 int set_memory_encrypted(unsigned long addr, int numpages) 136 { 137 int i; 138 139 /* make specified pages unshared, (swiotlb, dma_free) */ 140 for (i = 0; i < numpages; ++i) { 141 uv_remove_shared(addr); 142 addr += PAGE_SIZE; 143 } 144 return 0; 145 } 146 147 int set_memory_decrypted(unsigned long addr, int numpages) 148 { 149 int i; 150 /* make specified pages shared (swiotlb, dma_alloca) */ 151 for (i = 0; i < numpages; ++i) { 152 uv_set_shared(addr); 153 addr += PAGE_SIZE; 154 } 155 return 0; 156 } 157 158 /* are we a protected virtualization guest? */ 159 bool sev_active(void) 160 { 161 return is_prot_virt_guest(); 162 } 163 164 bool force_dma_unencrypted(struct device *dev) 165 { 166 return sev_active(); 167 } 168 169 /* protected virtualization */ 170 static void pv_init(void) 171 { 172 if (!is_prot_virt_guest()) 173 return; 174 175 /* make sure bounce buffers are shared */ 176 swiotlb_init(1); 177 swiotlb_update_mem_attributes(); 178 swiotlb_force = SWIOTLB_FORCE; 179 } 180 181 void __init mem_init(void) 182 { 183 cpumask_set_cpu(0, &init_mm.context.cpu_attach_mask); 184 cpumask_set_cpu(0, mm_cpumask(&init_mm)); 185 186 set_max_mapnr(max_low_pfn); 187 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 188 189 pv_init(); 190 191 /* Setup guest page hinting */ 192 cmma_init(); 193 194 /* this will put all low memory onto the freelists */ 195 memblock_free_all(); 196 setup_zero_pages(); /* Setup zeroed pages. */ 197 198 cmma_init_nodat(); 199 200 mem_init_print_info(NULL); 201 } 202 203 void free_initmem(void) 204 { 205 initmem_freed = true; 206 __set_memory((unsigned long)_sinittext, 207 (unsigned long)(_einittext - _sinittext) >> PAGE_SHIFT, 208 SET_MEMORY_RW | SET_MEMORY_NX); 209 free_initmem_default(POISON_FREE_INITMEM); 210 } 211 212 unsigned long memory_block_size_bytes(void) 213 { 214 /* 215 * Make sure the memory block size is always greater 216 * or equal than the memory increment size. 217 */ 218 return max_t(unsigned long, MIN_MEMORY_BLOCK_SIZE, sclp.rzm); 219 } 220 221 #ifdef CONFIG_MEMORY_HOTPLUG 222 223 #ifdef CONFIG_CMA 224 225 /* Prevent memory blocks which contain cma regions from going offline */ 226 227 struct s390_cma_mem_data { 228 unsigned long start; 229 unsigned long end; 230 }; 231 232 static int s390_cma_check_range(struct cma *cma, void *data) 233 { 234 struct s390_cma_mem_data *mem_data; 235 unsigned long start, end; 236 237 mem_data = data; 238 start = cma_get_base(cma); 239 end = start + cma_get_size(cma); 240 if (end < mem_data->start) 241 return 0; 242 if (start >= mem_data->end) 243 return 0; 244 return -EBUSY; 245 } 246 247 static int s390_cma_mem_notifier(struct notifier_block *nb, 248 unsigned long action, void *data) 249 { 250 struct s390_cma_mem_data mem_data; 251 struct memory_notify *arg; 252 int rc = 0; 253 254 arg = data; 255 mem_data.start = arg->start_pfn << PAGE_SHIFT; 256 mem_data.end = mem_data.start + (arg->nr_pages << PAGE_SHIFT); 257 if (action == MEM_GOING_OFFLINE) 258 rc = cma_for_each_area(s390_cma_check_range, &mem_data); 259 return notifier_from_errno(rc); 260 } 261 262 static struct notifier_block s390_cma_mem_nb = { 263 .notifier_call = s390_cma_mem_notifier, 264 }; 265 266 static int __init s390_cma_mem_init(void) 267 { 268 return register_memory_notifier(&s390_cma_mem_nb); 269 } 270 device_initcall(s390_cma_mem_init); 271 272 #endif /* CONFIG_CMA */ 273 274 int arch_add_memory(int nid, u64 start, u64 size, 275 struct mhp_restrictions *restrictions) 276 { 277 unsigned long start_pfn = PFN_DOWN(start); 278 unsigned long size_pages = PFN_DOWN(size); 279 int rc; 280 281 if (WARN_ON_ONCE(restrictions->altmap)) 282 return -EINVAL; 283 284 rc = vmem_add_mapping(start, size); 285 if (rc) 286 return rc; 287 288 rc = __add_pages(nid, start_pfn, size_pages, restrictions); 289 if (rc) 290 vmem_remove_mapping(start, size); 291 return rc; 292 } 293 294 void arch_remove_memory(int nid, u64 start, u64 size, 295 struct vmem_altmap *altmap) 296 { 297 unsigned long start_pfn = start >> PAGE_SHIFT; 298 unsigned long nr_pages = size >> PAGE_SHIFT; 299 struct zone *zone; 300 301 zone = page_zone(pfn_to_page(start_pfn)); 302 __remove_pages(zone, start_pfn, nr_pages, altmap); 303 vmem_remove_mapping(start, size); 304 } 305 #endif /* CONFIG_MEMORY_HOTPLUG */ 306