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 53 pgd_t swapper_pg_dir[PTRS_PER_PGD] __section(".bss..swapper_pg_dir"); 54 pgd_t invalid_pg_dir[PTRS_PER_PGD] __section(".bss..invalid_pg_dir"); 55 56 struct ctlreg __bootdata_preserved(s390_invalid_asce); 57 58 unsigned long empty_zero_page, zero_page_mask; 59 EXPORT_SYMBOL(empty_zero_page); 60 EXPORT_SYMBOL(zero_page_mask); 61 62 static void __init setup_zero_pages(void) 63 { 64 unsigned int order; 65 struct page *page; 66 int i; 67 68 /* Latest machines require a mapping granularity of 512KB */ 69 order = 7; 70 71 /* Limit number of empty zero pages for small memory sizes */ 72 while (order > 2 && (totalram_pages() >> 10) < (1UL << order)) 73 order--; 74 75 empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order); 76 if (!empty_zero_page) 77 panic("Out of memory in setup_zero_pages"); 78 79 page = virt_to_page((void *) empty_zero_page); 80 split_page(page, order); 81 for (i = 1 << order; i > 0; i--) { 82 mark_page_reserved(page); 83 page++; 84 } 85 86 zero_page_mask = ((PAGE_SIZE << order) - 1) & PAGE_MASK; 87 } 88 89 /* 90 * paging_init() sets up the page tables 91 */ 92 void __init paging_init(void) 93 { 94 unsigned long max_zone_pfns[MAX_NR_ZONES]; 95 96 vmem_map_init(); 97 sparse_init(); 98 zone_dma_bits = 31; 99 memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); 100 max_zone_pfns[ZONE_DMA] = virt_to_pfn(MAX_DMA_ADDRESS); 101 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 102 free_area_init(max_zone_pfns); 103 } 104 105 void mark_rodata_ro(void) 106 { 107 unsigned long size = __end_ro_after_init - __start_ro_after_init; 108 109 __set_memory_ro(__start_ro_after_init, __end_ro_after_init); 110 pr_info("Write protected read-only-after-init data: %luk\n", size >> 10); 111 } 112 113 int set_memory_encrypted(unsigned long vaddr, int numpages) 114 { 115 int i; 116 117 /* make specified pages unshared, (swiotlb, dma_free) */ 118 for (i = 0; i < numpages; ++i) { 119 uv_remove_shared(virt_to_phys((void *)vaddr)); 120 vaddr += PAGE_SIZE; 121 } 122 return 0; 123 } 124 125 int set_memory_decrypted(unsigned long vaddr, int numpages) 126 { 127 int i; 128 /* make specified pages shared (swiotlb, dma_alloca) */ 129 for (i = 0; i < numpages; ++i) { 130 uv_set_shared(virt_to_phys((void *)vaddr)); 131 vaddr += PAGE_SIZE; 132 } 133 return 0; 134 } 135 136 /* are we a protected virtualization guest? */ 137 bool force_dma_unencrypted(struct device *dev) 138 { 139 return is_prot_virt_guest(); 140 } 141 142 /* protected virtualization */ 143 static void pv_init(void) 144 { 145 if (!is_prot_virt_guest()) 146 return; 147 148 virtio_set_mem_acc_cb(virtio_require_restricted_mem_acc); 149 150 /* make sure bounce buffers are shared */ 151 swiotlb_init(true, SWIOTLB_FORCE | SWIOTLB_VERBOSE); 152 swiotlb_update_mem_attributes(); 153 } 154 155 void __init mem_init(void) 156 { 157 cpumask_set_cpu(0, &init_mm.context.cpu_attach_mask); 158 cpumask_set_cpu(0, mm_cpumask(&init_mm)); 159 160 set_max_mapnr(max_low_pfn); 161 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 162 163 pv_init(); 164 kfence_split_mapping(); 165 166 /* this will put all low memory onto the freelists */ 167 memblock_free_all(); 168 setup_zero_pages(); /* Setup zeroed pages. */ 169 } 170 171 void free_initmem(void) 172 { 173 set_memory_rwnx((unsigned long)_sinittext, 174 (unsigned long)(_einittext - _sinittext) >> PAGE_SHIFT); 175 free_initmem_default(POISON_FREE_INITMEM); 176 } 177 178 unsigned long memory_block_size_bytes(void) 179 { 180 /* 181 * Make sure the memory block size is always greater 182 * or equal than the memory increment size. 183 */ 184 return max_t(unsigned long, MIN_MEMORY_BLOCK_SIZE, sclp.rzm); 185 } 186 187 unsigned long __per_cpu_offset[NR_CPUS] __read_mostly; 188 EXPORT_SYMBOL(__per_cpu_offset); 189 190 static int __init pcpu_cpu_distance(unsigned int from, unsigned int to) 191 { 192 return LOCAL_DISTANCE; 193 } 194 195 static int __init pcpu_cpu_to_node(int cpu) 196 { 197 return 0; 198 } 199 200 void __init setup_per_cpu_areas(void) 201 { 202 unsigned long delta; 203 unsigned int cpu; 204 int rc; 205 206 /* 207 * Always reserve area for module percpu variables. That's 208 * what the legacy allocator did. 209 */ 210 rc = pcpu_embed_first_chunk(PERCPU_MODULE_RESERVE, 211 PERCPU_DYNAMIC_RESERVE, PAGE_SIZE, 212 pcpu_cpu_distance, 213 pcpu_cpu_to_node); 214 if (rc < 0) 215 panic("Failed to initialize percpu areas."); 216 217 delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start; 218 for_each_possible_cpu(cpu) 219 __per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu]; 220 } 221 222 #ifdef CONFIG_MEMORY_HOTPLUG 223 224 #ifdef CONFIG_CMA 225 226 /* Prevent memory blocks which contain cma regions from going offline */ 227 228 struct s390_cma_mem_data { 229 unsigned long start; 230 unsigned long end; 231 }; 232 233 static int s390_cma_check_range(struct cma *cma, void *data) 234 { 235 struct s390_cma_mem_data *mem_data; 236 unsigned long start, end; 237 238 mem_data = data; 239 start = cma_get_base(cma); 240 end = start + cma_get_size(cma); 241 if (end < mem_data->start) 242 return 0; 243 if (start >= mem_data->end) 244 return 0; 245 return -EBUSY; 246 } 247 248 static int s390_cma_mem_notifier(struct notifier_block *nb, 249 unsigned long action, void *data) 250 { 251 struct s390_cma_mem_data mem_data; 252 struct memory_notify *arg; 253 int rc = 0; 254 255 arg = data; 256 mem_data.start = arg->start_pfn << PAGE_SHIFT; 257 mem_data.end = mem_data.start + (arg->nr_pages << PAGE_SHIFT); 258 if (action == MEM_GOING_OFFLINE) 259 rc = cma_for_each_area(s390_cma_check_range, &mem_data); 260 return notifier_from_errno(rc); 261 } 262 263 static struct notifier_block s390_cma_mem_nb = { 264 .notifier_call = s390_cma_mem_notifier, 265 }; 266 267 static int __init s390_cma_mem_init(void) 268 { 269 return register_memory_notifier(&s390_cma_mem_nb); 270 } 271 device_initcall(s390_cma_mem_init); 272 273 #endif /* CONFIG_CMA */ 274 275 int arch_add_memory(int nid, u64 start, u64 size, 276 struct mhp_params *params) 277 { 278 unsigned long start_pfn = PFN_DOWN(start); 279 unsigned long size_pages = PFN_DOWN(size); 280 int rc; 281 282 if (WARN_ON_ONCE(params->pgprot.pgprot != PAGE_KERNEL.pgprot)) 283 return -EINVAL; 284 285 VM_BUG_ON(!mhp_range_allowed(start, size, true)); 286 rc = vmem_add_mapping(start, size); 287 if (rc) 288 return rc; 289 290 rc = __add_pages(nid, start_pfn, size_pages, params); 291 if (rc) 292 vmem_remove_mapping(start, size); 293 return rc; 294 } 295 296 void arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap) 297 { 298 unsigned long start_pfn = start >> PAGE_SHIFT; 299 unsigned long nr_pages = size >> PAGE_SHIFT; 300 301 __remove_pages(start_pfn, nr_pages, altmap); 302 vmem_remove_mapping(start, size); 303 } 304 #endif /* CONFIG_MEMORY_HOTPLUG */ 305