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/pgalloc.h> 37 #include <asm/dma.h> 38 #include <asm/lowcore.h> 39 #include <asm/tlb.h> 40 #include <asm/tlbflush.h> 41 #include <asm/sections.h> 42 #include <asm/ctl_reg.h> 43 #include <asm/sclp.h> 44 #include <asm/set_memory.h> 45 #include <asm/kasan.h> 46 #include <asm/dma-mapping.h> 47 #include <asm/uv.h> 48 49 pgd_t swapper_pg_dir[PTRS_PER_PGD] __section(.bss..swapper_pg_dir); 50 51 unsigned long empty_zero_page, zero_page_mask; 52 EXPORT_SYMBOL(empty_zero_page); 53 EXPORT_SYMBOL(zero_page_mask); 54 55 bool initmem_freed; 56 57 static void __init setup_zero_pages(void) 58 { 59 unsigned int order; 60 struct page *page; 61 int i; 62 63 /* Latest machines require a mapping granularity of 512KB */ 64 order = 7; 65 66 /* Limit number of empty zero pages for small memory sizes */ 67 while (order > 2 && (totalram_pages() >> 10) < (1UL << order)) 68 order--; 69 70 empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order); 71 if (!empty_zero_page) 72 panic("Out of memory in setup_zero_pages"); 73 74 page = virt_to_page((void *) empty_zero_page); 75 split_page(page, order); 76 for (i = 1 << order; i > 0; i--) { 77 mark_page_reserved(page); 78 page++; 79 } 80 81 zero_page_mask = ((PAGE_SIZE << order) - 1) & PAGE_MASK; 82 } 83 84 /* 85 * paging_init() sets up the page tables 86 */ 87 void __init paging_init(void) 88 { 89 unsigned long max_zone_pfns[MAX_NR_ZONES]; 90 unsigned long pgd_type, asce_bits; 91 psw_t psw; 92 93 init_mm.pgd = swapper_pg_dir; 94 if (VMALLOC_END > _REGION2_SIZE) { 95 asce_bits = _ASCE_TYPE_REGION2 | _ASCE_TABLE_LENGTH; 96 pgd_type = _REGION2_ENTRY_EMPTY; 97 } else { 98 asce_bits = _ASCE_TYPE_REGION3 | _ASCE_TABLE_LENGTH; 99 pgd_type = _REGION3_ENTRY_EMPTY; 100 } 101 init_mm.context.asce = (__pa(init_mm.pgd) & PAGE_MASK) | asce_bits; 102 S390_lowcore.kernel_asce = init_mm.context.asce; 103 S390_lowcore.user_asce = S390_lowcore.kernel_asce; 104 crst_table_init((unsigned long *) init_mm.pgd, pgd_type); 105 vmem_map_init(); 106 kasan_copy_shadow(init_mm.pgd); 107 108 /* enable virtual mapping in kernel mode */ 109 __ctl_load(S390_lowcore.kernel_asce, 1, 1); 110 __ctl_load(S390_lowcore.kernel_asce, 7, 7); 111 __ctl_load(S390_lowcore.kernel_asce, 13, 13); 112 psw.mask = __extract_psw(); 113 psw_bits(psw).dat = 1; 114 psw_bits(psw).as = PSW_BITS_AS_HOME; 115 __load_psw_mask(psw.mask); 116 kasan_free_early_identity(); 117 118 sparse_init(); 119 zone_dma_bits = 31; 120 memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); 121 max_zone_pfns[ZONE_DMA] = PFN_DOWN(MAX_DMA_ADDRESS); 122 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 123 free_area_init(max_zone_pfns); 124 } 125 126 void mark_rodata_ro(void) 127 { 128 unsigned long size = __end_ro_after_init - __start_ro_after_init; 129 130 set_memory_ro((unsigned long)__start_ro_after_init, size >> PAGE_SHIFT); 131 pr_info("Write protected read-only-after-init data: %luk\n", size >> 10); 132 } 133 134 int set_memory_encrypted(unsigned long addr, int numpages) 135 { 136 int i; 137 138 /* make specified pages unshared, (swiotlb, dma_free) */ 139 for (i = 0; i < numpages; ++i) { 140 uv_remove_shared(addr); 141 addr += PAGE_SIZE; 142 } 143 return 0; 144 } 145 146 int set_memory_decrypted(unsigned long addr, int numpages) 147 { 148 int i; 149 /* make specified pages shared (swiotlb, dma_alloca) */ 150 for (i = 0; i < numpages; ++i) { 151 uv_set_shared(addr); 152 addr += PAGE_SIZE; 153 } 154 return 0; 155 } 156 157 /* are we a protected virtualization guest? */ 158 bool force_dma_unencrypted(struct device *dev) 159 { 160 return is_prot_virt_guest(); 161 } 162 163 /* protected virtualization */ 164 static void pv_init(void) 165 { 166 if (!is_prot_virt_guest()) 167 return; 168 169 /* make sure bounce buffers are shared */ 170 swiotlb_init(1); 171 swiotlb_update_mem_attributes(); 172 swiotlb_force = SWIOTLB_FORCE; 173 } 174 175 void __init mem_init(void) 176 { 177 cpumask_set_cpu(0, &init_mm.context.cpu_attach_mask); 178 cpumask_set_cpu(0, mm_cpumask(&init_mm)); 179 180 set_max_mapnr(max_low_pfn); 181 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 182 183 pv_init(); 184 185 /* Setup guest page hinting */ 186 cmma_init(); 187 188 /* this will put all low memory onto the freelists */ 189 memblock_free_all(); 190 setup_zero_pages(); /* Setup zeroed pages. */ 191 192 cmma_init_nodat(); 193 194 mem_init_print_info(NULL); 195 } 196 197 void free_initmem(void) 198 { 199 initmem_freed = true; 200 __set_memory((unsigned long)_sinittext, 201 (unsigned long)(_einittext - _sinittext) >> PAGE_SHIFT, 202 SET_MEMORY_RW | SET_MEMORY_NX); 203 free_initmem_default(POISON_FREE_INITMEM); 204 } 205 206 unsigned long memory_block_size_bytes(void) 207 { 208 /* 209 * Make sure the memory block size is always greater 210 * or equal than the memory increment size. 211 */ 212 return max_t(unsigned long, MIN_MEMORY_BLOCK_SIZE, sclp.rzm); 213 } 214 215 #ifdef CONFIG_MEMORY_HOTPLUG 216 217 #ifdef CONFIG_CMA 218 219 /* Prevent memory blocks which contain cma regions from going offline */ 220 221 struct s390_cma_mem_data { 222 unsigned long start; 223 unsigned long end; 224 }; 225 226 static int s390_cma_check_range(struct cma *cma, void *data) 227 { 228 struct s390_cma_mem_data *mem_data; 229 unsigned long start, end; 230 231 mem_data = data; 232 start = cma_get_base(cma); 233 end = start + cma_get_size(cma); 234 if (end < mem_data->start) 235 return 0; 236 if (start >= mem_data->end) 237 return 0; 238 return -EBUSY; 239 } 240 241 static int s390_cma_mem_notifier(struct notifier_block *nb, 242 unsigned long action, void *data) 243 { 244 struct s390_cma_mem_data mem_data; 245 struct memory_notify *arg; 246 int rc = 0; 247 248 arg = data; 249 mem_data.start = arg->start_pfn << PAGE_SHIFT; 250 mem_data.end = mem_data.start + (arg->nr_pages << PAGE_SHIFT); 251 if (action == MEM_GOING_OFFLINE) 252 rc = cma_for_each_area(s390_cma_check_range, &mem_data); 253 return notifier_from_errno(rc); 254 } 255 256 static struct notifier_block s390_cma_mem_nb = { 257 .notifier_call = s390_cma_mem_notifier, 258 }; 259 260 static int __init s390_cma_mem_init(void) 261 { 262 return register_memory_notifier(&s390_cma_mem_nb); 263 } 264 device_initcall(s390_cma_mem_init); 265 266 #endif /* CONFIG_CMA */ 267 268 int arch_add_memory(int nid, u64 start, u64 size, 269 struct mhp_params *params) 270 { 271 unsigned long start_pfn = PFN_DOWN(start); 272 unsigned long size_pages = PFN_DOWN(size); 273 int rc; 274 275 if (WARN_ON_ONCE(params->altmap)) 276 return -EINVAL; 277 278 if (WARN_ON_ONCE(params->pgprot.pgprot != PAGE_KERNEL.pgprot)) 279 return -EINVAL; 280 281 rc = vmem_add_mapping(start, size); 282 if (rc) 283 return rc; 284 285 rc = __add_pages(nid, start_pfn, size_pages, params); 286 if (rc) 287 vmem_remove_mapping(start, size); 288 return rc; 289 } 290 291 void arch_remove_memory(int nid, u64 start, u64 size, 292 struct vmem_altmap *altmap) 293 { 294 unsigned long start_pfn = start >> PAGE_SHIFT; 295 unsigned long nr_pages = size >> PAGE_SHIFT; 296 297 __remove_pages(start_pfn, nr_pages, altmap); 298 vmem_remove_mapping(start, size); 299 } 300 #endif /* CONFIG_MEMORY_HOTPLUG */ 301