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 long total_pages = PHYS_PFN(memblock_phys_mem_size() - memblock_reserved_size()); 66 unsigned int order; 67 struct page *page; 68 int i; 69 70 /* Latest machines require a mapping granularity of 512KB */ 71 order = 7; 72 73 /* Limit number of empty zero pages for small memory sizes */ 74 while (order > 2 && (total_pages >> 10) < (1UL << order)) 75 order--; 76 77 empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order); 78 if (!empty_zero_page) 79 panic("Out of memory in setup_zero_pages"); 80 81 page = virt_to_page((void *) empty_zero_page); 82 split_page(page, order); 83 for (i = 1 << order; i > 0; i--) { 84 mark_page_reserved(page); 85 page++; 86 } 87 88 zero_page_mask = ((PAGE_SIZE << order) - 1) & PAGE_MASK; 89 } 90 91 /* 92 * paging_init() sets up the page tables 93 */ 94 void __init paging_init(void) 95 { 96 unsigned long max_zone_pfns[MAX_NR_ZONES]; 97 98 vmem_map_init(); 99 sparse_init(); 100 zone_dma_bits = 31; 101 memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); 102 max_zone_pfns[ZONE_DMA] = virt_to_pfn(MAX_DMA_ADDRESS); 103 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 104 free_area_init(max_zone_pfns); 105 } 106 107 void mark_rodata_ro(void) 108 { 109 unsigned long size = __end_ro_after_init - __start_ro_after_init; 110 111 if (MACHINE_HAS_NX) 112 system_ctl_set_bit(0, CR0_INSTRUCTION_EXEC_PROTECTION_BIT); 113 __set_memory_ro(__start_ro_after_init, __end_ro_after_init); 114 pr_info("Write protected read-only-after-init data: %luk\n", size >> 10); 115 } 116 117 int set_memory_encrypted(unsigned long vaddr, int numpages) 118 { 119 int i; 120 121 /* make specified pages unshared, (swiotlb, dma_free) */ 122 for (i = 0; i < numpages; ++i) { 123 uv_remove_shared(virt_to_phys((void *)vaddr)); 124 vaddr += PAGE_SIZE; 125 } 126 return 0; 127 } 128 129 int set_memory_decrypted(unsigned long vaddr, int numpages) 130 { 131 int i; 132 /* make specified pages shared (swiotlb, dma_alloca) */ 133 for (i = 0; i < numpages; ++i) { 134 uv_set_shared(virt_to_phys((void *)vaddr)); 135 vaddr += PAGE_SIZE; 136 } 137 return 0; 138 } 139 140 /* are we a protected virtualization guest? */ 141 bool force_dma_unencrypted(struct device *dev) 142 { 143 return is_prot_virt_guest(); 144 } 145 146 /* protected virtualization */ 147 static void pv_init(void) 148 { 149 if (!is_prot_virt_guest()) 150 return; 151 152 virtio_set_mem_acc_cb(virtio_require_restricted_mem_acc); 153 154 /* make sure bounce buffers are shared */ 155 swiotlb_init(true, SWIOTLB_FORCE | SWIOTLB_VERBOSE); 156 swiotlb_update_mem_attributes(); 157 } 158 159 void __init mem_init(void) 160 { 161 cpumask_set_cpu(0, &init_mm.context.cpu_attach_mask); 162 cpumask_set_cpu(0, mm_cpumask(&init_mm)); 163 164 set_max_mapnr(max_low_pfn); 165 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 166 167 pv_init(); 168 kfence_split_mapping(); 169 170 /* this will put all low memory onto the freelists */ 171 memblock_free_all(); 172 setup_zero_pages(); /* Setup zeroed pages. */ 173 } 174 175 unsigned long memory_block_size_bytes(void) 176 { 177 /* 178 * Make sure the memory block size is always greater 179 * or equal than the memory increment size. 180 */ 181 return max_t(unsigned long, MIN_MEMORY_BLOCK_SIZE, sclp.rzm); 182 } 183 184 unsigned long __per_cpu_offset[NR_CPUS] __read_mostly; 185 EXPORT_SYMBOL(__per_cpu_offset); 186 187 static int __init pcpu_cpu_distance(unsigned int from, unsigned int to) 188 { 189 return LOCAL_DISTANCE; 190 } 191 192 static int __init pcpu_cpu_to_node(int cpu) 193 { 194 return 0; 195 } 196 197 void __init setup_per_cpu_areas(void) 198 { 199 unsigned long delta; 200 unsigned int cpu; 201 int rc; 202 203 /* 204 * Always reserve area for module percpu variables. That's 205 * what the legacy allocator did. 206 */ 207 rc = pcpu_embed_first_chunk(PERCPU_MODULE_RESERVE, 208 PERCPU_DYNAMIC_RESERVE, PAGE_SIZE, 209 pcpu_cpu_distance, 210 pcpu_cpu_to_node); 211 if (rc < 0) 212 panic("Failed to initialize percpu areas."); 213 214 delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start; 215 for_each_possible_cpu(cpu) 216 __per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu]; 217 } 218 219 #ifdef CONFIG_MEMORY_HOTPLUG 220 221 #ifdef CONFIG_CMA 222 223 /* Prevent memory blocks which contain cma regions from going offline */ 224 225 struct s390_cma_mem_data { 226 unsigned long start; 227 unsigned long end; 228 }; 229 230 static int s390_cma_check_range(struct cma *cma, void *data) 231 { 232 struct s390_cma_mem_data *mem_data; 233 unsigned long start, end; 234 235 mem_data = data; 236 start = cma_get_base(cma); 237 end = start + cma_get_size(cma); 238 if (end < mem_data->start) 239 return 0; 240 if (start >= mem_data->end) 241 return 0; 242 return -EBUSY; 243 } 244 245 static int s390_cma_mem_notifier(struct notifier_block *nb, 246 unsigned long action, void *data) 247 { 248 struct s390_cma_mem_data mem_data; 249 struct memory_notify *arg; 250 int rc = 0; 251 252 arg = data; 253 mem_data.start = arg->start_pfn << PAGE_SHIFT; 254 mem_data.end = mem_data.start + (arg->nr_pages << PAGE_SHIFT); 255 if (action == MEM_GOING_OFFLINE) 256 rc = cma_for_each_area(s390_cma_check_range, &mem_data); 257 return notifier_from_errno(rc); 258 } 259 260 static struct notifier_block s390_cma_mem_nb = { 261 .notifier_call = s390_cma_mem_notifier, 262 }; 263 264 static int __init s390_cma_mem_init(void) 265 { 266 return register_memory_notifier(&s390_cma_mem_nb); 267 } 268 device_initcall(s390_cma_mem_init); 269 270 #endif /* CONFIG_CMA */ 271 272 int arch_add_memory(int nid, u64 start, u64 size, 273 struct mhp_params *params) 274 { 275 unsigned long start_pfn = PFN_DOWN(start); 276 unsigned long size_pages = PFN_DOWN(size); 277 int rc; 278 279 if (WARN_ON_ONCE(params->pgprot.pgprot != PAGE_KERNEL.pgprot)) 280 return -EINVAL; 281 282 VM_BUG_ON(!mhp_range_allowed(start, size, true)); 283 rc = vmem_add_mapping(start, size); 284 if (rc) 285 return rc; 286 287 rc = __add_pages(nid, start_pfn, size_pages, params); 288 if (rc) 289 vmem_remove_mapping(start, size); 290 return rc; 291 } 292 293 void arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap) 294 { 295 unsigned long start_pfn = start >> PAGE_SHIFT; 296 unsigned long nr_pages = size >> PAGE_SHIFT; 297 298 __remove_pages(start_pfn, nr_pages, altmap); 299 vmem_remove_mapping(start, size); 300 } 301 #endif /* CONFIG_MEMORY_HOTPLUG */ 302 303 #ifdef CONFIG_EXECMEM 304 static struct execmem_info execmem_info __ro_after_init; 305 306 struct execmem_info __init *execmem_arch_setup(void) 307 { 308 unsigned long module_load_offset = 0; 309 unsigned long start; 310 311 if (kaslr_enabled()) 312 module_load_offset = get_random_u32_inclusive(1, 1024) * PAGE_SIZE; 313 314 start = MODULES_VADDR + module_load_offset; 315 316 execmem_info = (struct execmem_info){ 317 .ranges = { 318 [EXECMEM_DEFAULT] = { 319 .flags = EXECMEM_KASAN_SHADOW, 320 .start = start, 321 .end = MODULES_END, 322 .pgprot = PAGE_KERNEL, 323 .alignment = MODULE_ALIGN, 324 }, 325 }, 326 }; 327 328 return &execmem_info; 329 } 330 #endif /* CONFIG_EXECMEM */ 331