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/cpufeature.h> 12 #include <linux/signal.h> 13 #include <linux/sched.h> 14 #include <linux/kernel.h> 15 #include <linux/errno.h> 16 #include <linux/string.h> 17 #include <linux/types.h> 18 #include <linux/ptrace.h> 19 #include <linux/mman.h> 20 #include <linux/mm.h> 21 #include <linux/swap.h> 22 #include <linux/swiotlb.h> 23 #include <linux/smp.h> 24 #include <linux/init.h> 25 #include <linux/pagemap.h> 26 #include <linux/memblock.h> 27 #include <linux/memory.h> 28 #include <linux/pfn.h> 29 #include <linux/poison.h> 30 #include <linux/initrd.h> 31 #include <linux/export.h> 32 #include <linux/cma.h> 33 #include <linux/gfp.h> 34 #include <linux/dma-direct.h> 35 #include <linux/percpu.h> 36 #include <asm/processor.h> 37 #include <linux/uaccess.h> 38 #include <asm/pgalloc.h> 39 #include <asm/ctlreg.h> 40 #include <asm/kfence.h> 41 #include <asm/dma.h> 42 #include <asm/abs_lowcore.h> 43 #include <asm/tlb.h> 44 #include <asm/tlbflush.h> 45 #include <asm/sections.h> 46 #include <asm/sclp.h> 47 #include <asm/set_memory.h> 48 #include <asm/kasan.h> 49 #include <asm/dma-mapping.h> 50 #include <asm/uv.h> 51 #include <linux/virtio_anchor.h> 52 #include <linux/virtio_config.h> 53 #include <linux/execmem.h> 54 55 pgd_t swapper_pg_dir[PTRS_PER_PGD] __section(".bss..swapper_pg_dir"); 56 pgd_t invalid_pg_dir[PTRS_PER_PGD] __section(".bss..invalid_pg_dir"); 57 58 struct ctlreg __bootdata_preserved(s390_invalid_asce); 59 60 unsigned long __bootdata_preserved(page_noexec_mask); 61 EXPORT_SYMBOL(page_noexec_mask); 62 63 unsigned long __bootdata_preserved(segment_noexec_mask); 64 EXPORT_SYMBOL(segment_noexec_mask); 65 66 unsigned long __bootdata_preserved(region_noexec_mask); 67 EXPORT_SYMBOL(region_noexec_mask); 68 69 unsigned long empty_zero_page, zero_page_mask; 70 EXPORT_SYMBOL(empty_zero_page); 71 EXPORT_SYMBOL(zero_page_mask); 72 73 static void __init setup_zero_pages(void) 74 { 75 unsigned long total_pages = memblock_estimated_nr_free_pages(); 76 unsigned int order; 77 78 /* Latest machines require a mapping granularity of 512KB */ 79 order = 7; 80 81 /* Limit number of empty zero pages for small memory sizes */ 82 while (order > 2 && (total_pages >> 10) < (1UL << order)) 83 order--; 84 85 empty_zero_page = (unsigned long)memblock_alloc_or_panic(PAGE_SIZE << order, PAGE_SIZE); 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_limit = DMA_BIT_MASK(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 if (cpu_has_nx()) 111 system_ctl_set_bit(0, CR0_INSTRUCTION_EXEC_PROTECTION_BIT); 112 __set_memory_ro(__start_ro_after_init, __end_ro_after_init); 113 pr_info("Write protected read-only-after-init data: %luk\n", size >> 10); 114 } 115 116 int set_memory_encrypted(unsigned long vaddr, int numpages) 117 { 118 int i; 119 120 /* make specified pages unshared, (swiotlb, dma_free) */ 121 for (i = 0; i < numpages; ++i) { 122 uv_remove_shared(virt_to_phys((void *)vaddr)); 123 vaddr += PAGE_SIZE; 124 } 125 return 0; 126 } 127 128 int set_memory_decrypted(unsigned long vaddr, int numpages) 129 { 130 int i; 131 /* make specified pages shared (swiotlb, dma_alloca) */ 132 for (i = 0; i < numpages; ++i) { 133 uv_set_shared(virt_to_phys((void *)vaddr)); 134 vaddr += PAGE_SIZE; 135 } 136 return 0; 137 } 138 139 /* are we a protected virtualization guest? */ 140 bool force_dma_unencrypted(struct device *dev) 141 { 142 return is_prot_virt_guest(); 143 } 144 145 /* protected virtualization */ 146 static void pv_init(void) 147 { 148 if (!is_prot_virt_guest()) 149 return; 150 151 virtio_set_mem_acc_cb(virtio_require_restricted_mem_acc); 152 153 /* make sure bounce buffers are shared */ 154 swiotlb_init(true, SWIOTLB_FORCE | SWIOTLB_VERBOSE); 155 swiotlb_update_mem_attributes(); 156 } 157 158 void __init arch_mm_preinit(void) 159 { 160 cpumask_set_cpu(0, &init_mm.context.cpu_attach_mask); 161 cpumask_set_cpu(0, mm_cpumask(&init_mm)); 162 163 pv_init(); 164 165 setup_zero_pages(); /* Setup zeroed pages. */ 166 } 167 168 unsigned long memory_block_size_bytes(void) 169 { 170 /* 171 * Make sure the memory block size is always greater 172 * or equal than the memory increment size. 173 */ 174 return max_t(unsigned long, MIN_MEMORY_BLOCK_SIZE, sclp.rzm); 175 } 176 177 unsigned long __per_cpu_offset[NR_CPUS] __read_mostly; 178 EXPORT_SYMBOL(__per_cpu_offset); 179 180 static int __init pcpu_cpu_distance(unsigned int from, unsigned int to) 181 { 182 return LOCAL_DISTANCE; 183 } 184 185 static int __init pcpu_cpu_to_node(int cpu) 186 { 187 return 0; 188 } 189 190 void __init setup_per_cpu_areas(void) 191 { 192 unsigned long delta; 193 unsigned int cpu; 194 int rc; 195 196 /* 197 * Always reserve area for module percpu variables. That's 198 * what the legacy allocator did. 199 */ 200 rc = pcpu_embed_first_chunk(PERCPU_MODULE_RESERVE, 201 PERCPU_DYNAMIC_RESERVE, PAGE_SIZE, 202 pcpu_cpu_distance, 203 pcpu_cpu_to_node); 204 if (rc < 0) 205 panic("Failed to initialize percpu areas."); 206 207 delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start; 208 for_each_possible_cpu(cpu) 209 __per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu]; 210 } 211 212 #ifdef CONFIG_MEMORY_HOTPLUG 213 214 #ifdef CONFIG_CMA 215 216 /* Prevent memory blocks which contain cma regions from going offline */ 217 218 struct s390_cma_mem_data { 219 unsigned long start; 220 unsigned long end; 221 }; 222 223 static int s390_cma_check_range(struct cma *cma, void *data) 224 { 225 struct s390_cma_mem_data *mem_data; 226 227 mem_data = data; 228 229 if (cma_intersects(cma, mem_data->start, mem_data->end)) 230 return -EBUSY; 231 232 return 0; 233 } 234 235 static int s390_cma_mem_notifier(struct notifier_block *nb, 236 unsigned long action, void *data) 237 { 238 struct s390_cma_mem_data mem_data; 239 struct memory_notify *arg; 240 int rc = 0; 241 242 arg = data; 243 mem_data.start = arg->start_pfn << PAGE_SHIFT; 244 mem_data.end = mem_data.start + (arg->nr_pages << PAGE_SHIFT); 245 if (action == MEM_GOING_OFFLINE) 246 rc = cma_for_each_area(s390_cma_check_range, &mem_data); 247 return notifier_from_errno(rc); 248 } 249 250 static struct notifier_block s390_cma_mem_nb = { 251 .notifier_call = s390_cma_mem_notifier, 252 }; 253 254 static int __init s390_cma_mem_init(void) 255 { 256 return register_memory_notifier(&s390_cma_mem_nb); 257 } 258 device_initcall(s390_cma_mem_init); 259 260 #endif /* CONFIG_CMA */ 261 262 int arch_add_memory(int nid, u64 start, u64 size, 263 struct mhp_params *params) 264 { 265 unsigned long start_pfn = PFN_DOWN(start); 266 unsigned long size_pages = PFN_DOWN(size); 267 int rc; 268 269 if (WARN_ON_ONCE(pgprot_val(params->pgprot) != pgprot_val(PAGE_KERNEL))) 270 return -EINVAL; 271 272 VM_BUG_ON(!mhp_range_allowed(start, size, true)); 273 rc = vmem_add_mapping(start, size); 274 if (rc) 275 return rc; 276 277 rc = __add_pages(nid, start_pfn, size_pages, params); 278 if (rc) 279 vmem_remove_mapping(start, size); 280 return rc; 281 } 282 283 void arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap) 284 { 285 unsigned long start_pfn = start >> PAGE_SHIFT; 286 unsigned long nr_pages = size >> PAGE_SHIFT; 287 288 __remove_pages(start_pfn, nr_pages, altmap); 289 vmem_remove_mapping(start, size); 290 } 291 #endif /* CONFIG_MEMORY_HOTPLUG */ 292 293 #ifdef CONFIG_EXECMEM 294 static struct execmem_info execmem_info __ro_after_init; 295 296 struct execmem_info __init *execmem_arch_setup(void) 297 { 298 unsigned long module_load_offset = 0; 299 unsigned long start; 300 301 if (kaslr_enabled()) 302 module_load_offset = get_random_u32_inclusive(1, 1024) * PAGE_SIZE; 303 304 start = MODULES_VADDR + module_load_offset; 305 306 execmem_info = (struct execmem_info){ 307 .ranges = { 308 [EXECMEM_DEFAULT] = { 309 .flags = EXECMEM_KASAN_SHADOW, 310 .start = start, 311 .end = MODULES_END, 312 .pgprot = PAGE_KERNEL, 313 .alignment = MODULE_ALIGN, 314 }, 315 }, 316 }; 317 318 return &execmem_info; 319 } 320 #endif /* CONFIG_EXECMEM */ 321