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 <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/dma.h> 41 #include <asm/abs_lowcore.h> 42 #include <asm/tlb.h> 43 #include <asm/tlbflush.h> 44 #include <asm/sections.h> 45 #include <asm/sclp.h> 46 #include <asm/set_memory.h> 47 #include <asm/kasan.h> 48 #include <asm/dma-mapping.h> 49 #include <asm/uv.h> 50 #include <linux/virtio_anchor.h> 51 #include <linux/virtio_config.h> 52 #include <linux/execmem.h> 53 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"); 56 57 struct ctlreg __bootdata_preserved(s390_invalid_asce); 58 59 unsigned long empty_zero_page, zero_page_mask; 60 EXPORT_SYMBOL(empty_zero_page); 61 EXPORT_SYMBOL(zero_page_mask); 62 63 static void __init setup_zero_pages(void) 64 { 65 unsigned int order; 66 struct page *page; 67 int i; 68 69 /* Latest machines require a mapping granularity of 512KB */ 70 order = 7; 71 72 /* Limit number of empty zero pages for small memory sizes */ 73 while (order > 2 && (totalram_pages() >> 10) < (1UL << order)) 74 order--; 75 76 empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order); 77 if (!empty_zero_page) 78 panic("Out of memory in setup_zero_pages"); 79 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); 84 page++; 85 } 86 87 zero_page_mask = ((PAGE_SIZE << order) - 1) & PAGE_MASK; 88 } 89 90 /* 91 * paging_init() sets up the page tables 92 */ 93 void __init paging_init(void) 94 { 95 unsigned long max_zone_pfns[MAX_NR_ZONES]; 96 97 vmem_map_init(); 98 sparse_init(); 99 zone_dma_bits = 31; 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); 104 } 105 106 void mark_rodata_ro(void) 107 { 108 unsigned long size = __end_ro_after_init - __start_ro_after_init; 109 110 __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); 112 } 113 114 int set_memory_encrypted(unsigned long vaddr, int numpages) 115 { 116 int i; 117 118 /* make specified pages unshared, (swiotlb, dma_free) */ 119 for (i = 0; i < numpages; ++i) { 120 uv_remove_shared(virt_to_phys((void *)vaddr)); 121 vaddr += PAGE_SIZE; 122 } 123 return 0; 124 } 125 126 int set_memory_decrypted(unsigned long vaddr, int numpages) 127 { 128 int i; 129 /* make specified pages shared (swiotlb, dma_alloca) */ 130 for (i = 0; i < numpages; ++i) { 131 uv_set_shared(virt_to_phys((void *)vaddr)); 132 vaddr += PAGE_SIZE; 133 } 134 return 0; 135 } 136 137 /* are we a protected virtualization guest? */ 138 bool force_dma_unencrypted(struct device *dev) 139 { 140 return is_prot_virt_guest(); 141 } 142 143 /* protected virtualization */ 144 static void pv_init(void) 145 { 146 if (!is_prot_virt_guest()) 147 return; 148 149 virtio_set_mem_acc_cb(virtio_require_restricted_mem_acc); 150 151 /* make sure bounce buffers are shared */ 152 swiotlb_init(true, SWIOTLB_FORCE | SWIOTLB_VERBOSE); 153 swiotlb_update_mem_attributes(); 154 } 155 156 void __init mem_init(void) 157 { 158 cpumask_set_cpu(0, &init_mm.context.cpu_attach_mask); 159 cpumask_set_cpu(0, mm_cpumask(&init_mm)); 160 161 set_max_mapnr(max_low_pfn); 162 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 163 164 pv_init(); 165 kfence_split_mapping(); 166 167 /* this will put all low memory onto the freelists */ 168 memblock_free_all(); 169 setup_zero_pages(); /* Setup zeroed pages. */ 170 } 171 172 void free_initmem(void) 173 { 174 set_memory_rwnx((unsigned long)_sinittext, 175 (unsigned long)(_einittext - _sinittext) >> PAGE_SHIFT); 176 free_initmem_default(POISON_FREE_INITMEM); 177 } 178 179 unsigned long memory_block_size_bytes(void) 180 { 181 /* 182 * Make sure the memory block size is always greater 183 * or equal than the memory increment size. 184 */ 185 return max_t(unsigned long, MIN_MEMORY_BLOCK_SIZE, sclp.rzm); 186 } 187 188 unsigned long __per_cpu_offset[NR_CPUS] __read_mostly; 189 EXPORT_SYMBOL(__per_cpu_offset); 190 191 static int __init pcpu_cpu_distance(unsigned int from, unsigned int to) 192 { 193 return LOCAL_DISTANCE; 194 } 195 196 static int __init pcpu_cpu_to_node(int cpu) 197 { 198 return 0; 199 } 200 201 void __init setup_per_cpu_areas(void) 202 { 203 unsigned long delta; 204 unsigned int cpu; 205 int rc; 206 207 /* 208 * Always reserve area for module percpu variables. That's 209 * what the legacy allocator did. 210 */ 211 rc = pcpu_embed_first_chunk(PERCPU_MODULE_RESERVE, 212 PERCPU_DYNAMIC_RESERVE, PAGE_SIZE, 213 pcpu_cpu_distance, 214 pcpu_cpu_to_node); 215 if (rc < 0) 216 panic("Failed to initialize percpu areas."); 217 218 delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start; 219 for_each_possible_cpu(cpu) 220 __per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu]; 221 } 222 223 #ifdef CONFIG_MEMORY_HOTPLUG 224 225 #ifdef CONFIG_CMA 226 227 /* Prevent memory blocks which contain cma regions from going offline */ 228 229 struct s390_cma_mem_data { 230 unsigned long start; 231 unsigned long end; 232 }; 233 234 static int s390_cma_check_range(struct cma *cma, void *data) 235 { 236 struct s390_cma_mem_data *mem_data; 237 unsigned long start, end; 238 239 mem_data = data; 240 start = cma_get_base(cma); 241 end = start + cma_get_size(cma); 242 if (end < mem_data->start) 243 return 0; 244 if (start >= mem_data->end) 245 return 0; 246 return -EBUSY; 247 } 248 249 static int s390_cma_mem_notifier(struct notifier_block *nb, 250 unsigned long action, void *data) 251 { 252 struct s390_cma_mem_data mem_data; 253 struct memory_notify *arg; 254 int rc = 0; 255 256 arg = data; 257 mem_data.start = arg->start_pfn << PAGE_SHIFT; 258 mem_data.end = mem_data.start + (arg->nr_pages << PAGE_SHIFT); 259 if (action == MEM_GOING_OFFLINE) 260 rc = cma_for_each_area(s390_cma_check_range, &mem_data); 261 return notifier_from_errno(rc); 262 } 263 264 static struct notifier_block s390_cma_mem_nb = { 265 .notifier_call = s390_cma_mem_notifier, 266 }; 267 268 static int __init s390_cma_mem_init(void) 269 { 270 return register_memory_notifier(&s390_cma_mem_nb); 271 } 272 device_initcall(s390_cma_mem_init); 273 274 #endif /* CONFIG_CMA */ 275 276 int arch_add_memory(int nid, u64 start, u64 size, 277 struct mhp_params *params) 278 { 279 unsigned long start_pfn = PFN_DOWN(start); 280 unsigned long size_pages = PFN_DOWN(size); 281 int rc; 282 283 if (WARN_ON_ONCE(params->pgprot.pgprot != PAGE_KERNEL.pgprot)) 284 return -EINVAL; 285 286 VM_BUG_ON(!mhp_range_allowed(start, size, true)); 287 rc = vmem_add_mapping(start, size); 288 if (rc) 289 return rc; 290 291 rc = __add_pages(nid, start_pfn, size_pages, params); 292 if (rc) 293 vmem_remove_mapping(start, size); 294 return rc; 295 } 296 297 void arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap) 298 { 299 unsigned long start_pfn = start >> PAGE_SHIFT; 300 unsigned long nr_pages = size >> PAGE_SHIFT; 301 302 __remove_pages(start_pfn, nr_pages, altmap); 303 vmem_remove_mapping(start, size); 304 } 305 #endif /* CONFIG_MEMORY_HOTPLUG */ 306 307 #ifdef CONFIG_EXECMEM 308 static struct execmem_info execmem_info __ro_after_init; 309 310 struct execmem_info __init *execmem_arch_setup(void) 311 { 312 unsigned long module_load_offset = 0; 313 unsigned long start; 314 315 if (kaslr_enabled()) 316 module_load_offset = get_random_u32_inclusive(1, 1024) * PAGE_SIZE; 317 318 start = MODULES_VADDR + module_load_offset; 319 320 execmem_info = (struct execmem_info){ 321 .ranges = { 322 [EXECMEM_DEFAULT] = { 323 .flags = EXECMEM_KASAN_SHADOW, 324 .start = start, 325 .end = MODULES_END, 326 .pgprot = PAGE_KERNEL, 327 .alignment = MODULE_ALIGN, 328 }, 329 }, 330 }; 331 332 return &execmem_info; 333 } 334 #endif /* CONFIG_EXECMEM */ 335