Kyle Swenson | 8d8f654 | 2021-03-15 11:02:55 -0600 | [diff] [blame^] | 1 | /* |
| 2 | * linux/arch/arm/mm/init.c |
| 3 | * |
| 4 | * Copyright (C) 1995-2005 Russell King |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License version 2 as |
| 8 | * published by the Free Software Foundation. |
| 9 | */ |
| 10 | #include <linux/kernel.h> |
| 11 | #include <linux/errno.h> |
| 12 | #include <linux/swap.h> |
| 13 | #include <linux/init.h> |
| 14 | #include <linux/bootmem.h> |
| 15 | #include <linux/mman.h> |
| 16 | #include <linux/export.h> |
| 17 | #include <linux/nodemask.h> |
| 18 | #include <linux/initrd.h> |
| 19 | #include <linux/of_fdt.h> |
| 20 | #include <linux/highmem.h> |
| 21 | #include <linux/gfp.h> |
| 22 | #include <linux/memblock.h> |
| 23 | #include <linux/dma-contiguous.h> |
| 24 | #include <linux/sizes.h> |
| 25 | #include <linux/stop_machine.h> |
| 26 | |
| 27 | #include <asm/cp15.h> |
| 28 | #include <asm/mach-types.h> |
| 29 | #include <asm/memblock.h> |
| 30 | #include <asm/prom.h> |
| 31 | #include <asm/sections.h> |
| 32 | #include <asm/setup.h> |
| 33 | #include <asm/system_info.h> |
| 34 | #include <asm/tlb.h> |
| 35 | #include <asm/fixmap.h> |
| 36 | |
| 37 | #include <asm/mach/arch.h> |
| 38 | #include <asm/mach/map.h> |
| 39 | |
| 40 | #include "mm.h" |
| 41 | |
| 42 | #ifdef CONFIG_CPU_CP15_MMU |
| 43 | unsigned long __init __clear_cr(unsigned long mask) |
| 44 | { |
| 45 | cr_alignment = cr_alignment & ~mask; |
| 46 | return cr_alignment; |
| 47 | } |
| 48 | #endif |
| 49 | |
| 50 | static phys_addr_t phys_initrd_start __initdata = 0; |
| 51 | static unsigned long phys_initrd_size __initdata = 0; |
| 52 | |
| 53 | static int __init early_initrd(char *p) |
| 54 | { |
| 55 | phys_addr_t start; |
| 56 | unsigned long size; |
| 57 | char *endp; |
| 58 | |
| 59 | start = memparse(p, &endp); |
| 60 | if (*endp == ',') { |
| 61 | size = memparse(endp + 1, NULL); |
| 62 | |
| 63 | phys_initrd_start = start; |
| 64 | phys_initrd_size = size; |
| 65 | } |
| 66 | return 0; |
| 67 | } |
| 68 | early_param("initrd", early_initrd); |
| 69 | |
| 70 | static int __init parse_tag_initrd(const struct tag *tag) |
| 71 | { |
| 72 | pr_warn("ATAG_INITRD is deprecated; " |
| 73 | "please update your bootloader.\n"); |
| 74 | phys_initrd_start = __virt_to_phys(tag->u.initrd.start); |
| 75 | phys_initrd_size = tag->u.initrd.size; |
| 76 | return 0; |
| 77 | } |
| 78 | |
| 79 | __tagtable(ATAG_INITRD, parse_tag_initrd); |
| 80 | |
| 81 | static int __init parse_tag_initrd2(const struct tag *tag) |
| 82 | { |
| 83 | phys_initrd_start = tag->u.initrd.start; |
| 84 | phys_initrd_size = tag->u.initrd.size; |
| 85 | return 0; |
| 86 | } |
| 87 | |
| 88 | __tagtable(ATAG_INITRD2, parse_tag_initrd2); |
| 89 | |
| 90 | static void __init find_limits(unsigned long *min, unsigned long *max_low, |
| 91 | unsigned long *max_high) |
| 92 | { |
| 93 | *max_low = PFN_DOWN(memblock_get_current_limit()); |
| 94 | *min = PFN_UP(memblock_start_of_DRAM()); |
| 95 | *max_high = PFN_DOWN(memblock_end_of_DRAM()); |
| 96 | } |
| 97 | |
| 98 | #ifdef CONFIG_ZONE_DMA |
| 99 | |
| 100 | phys_addr_t arm_dma_zone_size __read_mostly; |
| 101 | EXPORT_SYMBOL(arm_dma_zone_size); |
| 102 | |
| 103 | /* |
| 104 | * The DMA mask corresponding to the maximum bus address allocatable |
| 105 | * using GFP_DMA. The default here places no restriction on DMA |
| 106 | * allocations. This must be the smallest DMA mask in the system, |
| 107 | * so a successful GFP_DMA allocation will always satisfy this. |
| 108 | */ |
| 109 | phys_addr_t arm_dma_limit; |
| 110 | unsigned long arm_dma_pfn_limit; |
| 111 | |
| 112 | static void __init arm_adjust_dma_zone(unsigned long *size, unsigned long *hole, |
| 113 | unsigned long dma_size) |
| 114 | { |
| 115 | if (size[0] <= dma_size) |
| 116 | return; |
| 117 | |
| 118 | size[ZONE_NORMAL] = size[0] - dma_size; |
| 119 | size[ZONE_DMA] = dma_size; |
| 120 | hole[ZONE_NORMAL] = hole[0]; |
| 121 | hole[ZONE_DMA] = 0; |
| 122 | } |
| 123 | #endif |
| 124 | |
| 125 | void __init setup_dma_zone(const struct machine_desc *mdesc) |
| 126 | { |
| 127 | #ifdef CONFIG_ZONE_DMA |
| 128 | if (mdesc->dma_zone_size) { |
| 129 | arm_dma_zone_size = mdesc->dma_zone_size; |
| 130 | arm_dma_limit = PHYS_OFFSET + arm_dma_zone_size - 1; |
| 131 | } else |
| 132 | arm_dma_limit = 0xffffffff; |
| 133 | arm_dma_pfn_limit = arm_dma_limit >> PAGE_SHIFT; |
| 134 | #endif |
| 135 | } |
| 136 | |
| 137 | static void __init zone_sizes_init(unsigned long min, unsigned long max_low, |
| 138 | unsigned long max_high) |
| 139 | { |
| 140 | unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES]; |
| 141 | struct memblock_region *reg; |
| 142 | |
| 143 | /* |
| 144 | * initialise the zones. |
| 145 | */ |
| 146 | memset(zone_size, 0, sizeof(zone_size)); |
| 147 | |
| 148 | /* |
| 149 | * The memory size has already been determined. If we need |
| 150 | * to do anything fancy with the allocation of this memory |
| 151 | * to the zones, now is the time to do it. |
| 152 | */ |
| 153 | zone_size[0] = max_low - min; |
| 154 | #ifdef CONFIG_HIGHMEM |
| 155 | zone_size[ZONE_HIGHMEM] = max_high - max_low; |
| 156 | #endif |
| 157 | |
| 158 | /* |
| 159 | * Calculate the size of the holes. |
| 160 | * holes = node_size - sum(bank_sizes) |
| 161 | */ |
| 162 | memcpy(zhole_size, zone_size, sizeof(zhole_size)); |
| 163 | for_each_memblock(memory, reg) { |
| 164 | unsigned long start = memblock_region_memory_base_pfn(reg); |
| 165 | unsigned long end = memblock_region_memory_end_pfn(reg); |
| 166 | |
| 167 | if (start < max_low) { |
| 168 | unsigned long low_end = min(end, max_low); |
| 169 | zhole_size[0] -= low_end - start; |
| 170 | } |
| 171 | #ifdef CONFIG_HIGHMEM |
| 172 | if (end > max_low) { |
| 173 | unsigned long high_start = max(start, max_low); |
| 174 | zhole_size[ZONE_HIGHMEM] -= end - high_start; |
| 175 | } |
| 176 | #endif |
| 177 | } |
| 178 | |
| 179 | #ifdef CONFIG_ZONE_DMA |
| 180 | /* |
| 181 | * Adjust the sizes according to any special requirements for |
| 182 | * this machine type. |
| 183 | */ |
| 184 | if (arm_dma_zone_size) |
| 185 | arm_adjust_dma_zone(zone_size, zhole_size, |
| 186 | arm_dma_zone_size >> PAGE_SHIFT); |
| 187 | #endif |
| 188 | |
| 189 | free_area_init_node(0, zone_size, min, zhole_size); |
| 190 | } |
| 191 | |
| 192 | #ifdef CONFIG_HAVE_ARCH_PFN_VALID |
| 193 | int pfn_valid(unsigned long pfn) |
| 194 | { |
| 195 | return memblock_is_memory(__pfn_to_phys(pfn)); |
| 196 | } |
| 197 | EXPORT_SYMBOL(pfn_valid); |
| 198 | #endif |
| 199 | |
| 200 | #ifndef CONFIG_SPARSEMEM |
| 201 | static void __init arm_memory_present(void) |
| 202 | { |
| 203 | } |
| 204 | #else |
| 205 | static void __init arm_memory_present(void) |
| 206 | { |
| 207 | struct memblock_region *reg; |
| 208 | |
| 209 | for_each_memblock(memory, reg) |
| 210 | memory_present(0, memblock_region_memory_base_pfn(reg), |
| 211 | memblock_region_memory_end_pfn(reg)); |
| 212 | } |
| 213 | #endif |
| 214 | |
| 215 | static bool arm_memblock_steal_permitted = true; |
| 216 | |
| 217 | phys_addr_t __init arm_memblock_steal(phys_addr_t size, phys_addr_t align) |
| 218 | { |
| 219 | phys_addr_t phys; |
| 220 | |
| 221 | BUG_ON(!arm_memblock_steal_permitted); |
| 222 | |
| 223 | phys = memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ANYWHERE); |
| 224 | memblock_free(phys, size); |
| 225 | memblock_remove(phys, size); |
| 226 | |
| 227 | return phys; |
| 228 | } |
| 229 | |
| 230 | void __init arm_memblock_init(const struct machine_desc *mdesc) |
| 231 | { |
| 232 | /* Register the kernel text, kernel data and initrd with memblock. */ |
| 233 | #ifdef CONFIG_XIP_KERNEL |
| 234 | memblock_reserve(__pa(_sdata), _end - _sdata); |
| 235 | #else |
| 236 | memblock_reserve(__pa(_stext), _end - _stext); |
| 237 | #endif |
| 238 | #ifdef CONFIG_BLK_DEV_INITRD |
| 239 | /* FDT scan will populate initrd_start */ |
| 240 | if (initrd_start && !phys_initrd_size) { |
| 241 | phys_initrd_start = __virt_to_phys(initrd_start); |
| 242 | phys_initrd_size = initrd_end - initrd_start; |
| 243 | } |
| 244 | initrd_start = initrd_end = 0; |
| 245 | if (phys_initrd_size && |
| 246 | !memblock_is_region_memory(phys_initrd_start, phys_initrd_size)) { |
| 247 | pr_err("INITRD: 0x%08llx+0x%08lx is not a memory region - disabling initrd\n", |
| 248 | (u64)phys_initrd_start, phys_initrd_size); |
| 249 | phys_initrd_start = phys_initrd_size = 0; |
| 250 | } |
| 251 | if (phys_initrd_size && |
| 252 | memblock_is_region_reserved(phys_initrd_start, phys_initrd_size)) { |
| 253 | pr_err("INITRD: 0x%08llx+0x%08lx overlaps in-use memory region - disabling initrd\n", |
| 254 | (u64)phys_initrd_start, phys_initrd_size); |
| 255 | phys_initrd_start = phys_initrd_size = 0; |
| 256 | } |
| 257 | if (phys_initrd_size) { |
| 258 | memblock_reserve(phys_initrd_start, phys_initrd_size); |
| 259 | |
| 260 | /* Now convert initrd to virtual addresses */ |
| 261 | initrd_start = __phys_to_virt(phys_initrd_start); |
| 262 | initrd_end = initrd_start + phys_initrd_size; |
| 263 | } |
| 264 | #endif |
| 265 | |
| 266 | arm_mm_memblock_reserve(); |
| 267 | |
| 268 | /* reserve any platform specific memblock areas */ |
| 269 | if (mdesc->reserve) |
| 270 | mdesc->reserve(); |
| 271 | |
| 272 | early_init_fdt_reserve_self(); |
| 273 | early_init_fdt_scan_reserved_mem(); |
| 274 | |
| 275 | /* reserve memory for DMA contiguous allocations */ |
| 276 | dma_contiguous_reserve(arm_dma_limit); |
| 277 | |
| 278 | arm_memblock_steal_permitted = false; |
| 279 | memblock_dump_all(); |
| 280 | } |
| 281 | |
| 282 | void __init bootmem_init(void) |
| 283 | { |
| 284 | unsigned long min, max_low, max_high; |
| 285 | |
| 286 | memblock_allow_resize(); |
| 287 | max_low = max_high = 0; |
| 288 | |
| 289 | find_limits(&min, &max_low, &max_high); |
| 290 | |
| 291 | early_memtest((phys_addr_t)min << PAGE_SHIFT, |
| 292 | (phys_addr_t)max_low << PAGE_SHIFT); |
| 293 | |
| 294 | /* |
| 295 | * Sparsemem tries to allocate bootmem in memory_present(), |
| 296 | * so must be done after the fixed reservations |
| 297 | */ |
| 298 | arm_memory_present(); |
| 299 | |
| 300 | /* |
| 301 | * sparse_init() needs the bootmem allocator up and running. |
| 302 | */ |
| 303 | sparse_init(); |
| 304 | |
| 305 | /* |
| 306 | * Now free the memory - free_area_init_node needs |
| 307 | * the sparse mem_map arrays initialized by sparse_init() |
| 308 | * for memmap_init_zone(), otherwise all PFNs are invalid. |
| 309 | */ |
| 310 | zone_sizes_init(min, max_low, max_high); |
| 311 | |
| 312 | /* |
| 313 | * This doesn't seem to be used by the Linux memory manager any |
| 314 | * more, but is used by ll_rw_block. If we can get rid of it, we |
| 315 | * also get rid of some of the stuff above as well. |
| 316 | */ |
| 317 | min_low_pfn = min; |
| 318 | max_low_pfn = max_low; |
| 319 | max_pfn = max_high; |
| 320 | } |
| 321 | |
| 322 | /* |
| 323 | * Poison init memory with an undefined instruction (ARM) or a branch to an |
| 324 | * undefined instruction (Thumb). |
| 325 | */ |
| 326 | static inline void poison_init_mem(void *s, size_t count) |
| 327 | { |
| 328 | u32 *p = (u32 *)s; |
| 329 | for (; count != 0; count -= 4) |
| 330 | *p++ = 0xe7fddef0; |
| 331 | } |
| 332 | |
| 333 | static inline void |
| 334 | free_memmap(unsigned long start_pfn, unsigned long end_pfn) |
| 335 | { |
| 336 | struct page *start_pg, *end_pg; |
| 337 | phys_addr_t pg, pgend; |
| 338 | |
| 339 | /* |
| 340 | * Convert start_pfn/end_pfn to a struct page pointer. |
| 341 | */ |
| 342 | start_pg = pfn_to_page(start_pfn - 1) + 1; |
| 343 | end_pg = pfn_to_page(end_pfn - 1) + 1; |
| 344 | |
| 345 | /* |
| 346 | * Convert to physical addresses, and |
| 347 | * round start upwards and end downwards. |
| 348 | */ |
| 349 | pg = PAGE_ALIGN(__pa(start_pg)); |
| 350 | pgend = __pa(end_pg) & PAGE_MASK; |
| 351 | |
| 352 | /* |
| 353 | * If there are free pages between these, |
| 354 | * free the section of the memmap array. |
| 355 | */ |
| 356 | if (pg < pgend) |
| 357 | memblock_free_early(pg, pgend - pg); |
| 358 | } |
| 359 | |
| 360 | /* |
| 361 | * The mem_map array can get very big. Free the unused area of the memory map. |
| 362 | */ |
| 363 | static void __init free_unused_memmap(void) |
| 364 | { |
| 365 | unsigned long start, prev_end = 0; |
| 366 | struct memblock_region *reg; |
| 367 | |
| 368 | /* |
| 369 | * This relies on each bank being in address order. |
| 370 | * The banks are sorted previously in bootmem_init(). |
| 371 | */ |
| 372 | for_each_memblock(memory, reg) { |
| 373 | start = memblock_region_memory_base_pfn(reg); |
| 374 | |
| 375 | #ifdef CONFIG_SPARSEMEM |
| 376 | /* |
| 377 | * Take care not to free memmap entries that don't exist |
| 378 | * due to SPARSEMEM sections which aren't present. |
| 379 | */ |
| 380 | start = min(start, |
| 381 | ALIGN(prev_end, PAGES_PER_SECTION)); |
| 382 | #else |
| 383 | /* |
| 384 | * Align down here since the VM subsystem insists that the |
| 385 | * memmap entries are valid from the bank start aligned to |
| 386 | * MAX_ORDER_NR_PAGES. |
| 387 | */ |
| 388 | start = round_down(start, MAX_ORDER_NR_PAGES); |
| 389 | #endif |
| 390 | /* |
| 391 | * If we had a previous bank, and there is a space |
| 392 | * between the current bank and the previous, free it. |
| 393 | */ |
| 394 | if (prev_end && prev_end < start) |
| 395 | free_memmap(prev_end, start); |
| 396 | |
| 397 | /* |
| 398 | * Align up here since the VM subsystem insists that the |
| 399 | * memmap entries are valid from the bank end aligned to |
| 400 | * MAX_ORDER_NR_PAGES. |
| 401 | */ |
| 402 | prev_end = ALIGN(memblock_region_memory_end_pfn(reg), |
| 403 | MAX_ORDER_NR_PAGES); |
| 404 | } |
| 405 | |
| 406 | #ifdef CONFIG_SPARSEMEM |
| 407 | if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION)) |
| 408 | free_memmap(prev_end, |
| 409 | ALIGN(prev_end, PAGES_PER_SECTION)); |
| 410 | #endif |
| 411 | } |
| 412 | |
| 413 | #ifdef CONFIG_HIGHMEM |
| 414 | static inline void free_area_high(unsigned long pfn, unsigned long end) |
| 415 | { |
| 416 | for (; pfn < end; pfn++) |
| 417 | free_highmem_page(pfn_to_page(pfn)); |
| 418 | } |
| 419 | #endif |
| 420 | |
| 421 | static void __init free_highpages(void) |
| 422 | { |
| 423 | #ifdef CONFIG_HIGHMEM |
| 424 | unsigned long max_low = max_low_pfn; |
| 425 | struct memblock_region *mem, *res; |
| 426 | |
| 427 | /* set highmem page free */ |
| 428 | for_each_memblock(memory, mem) { |
| 429 | unsigned long start = memblock_region_memory_base_pfn(mem); |
| 430 | unsigned long end = memblock_region_memory_end_pfn(mem); |
| 431 | |
| 432 | /* Ignore complete lowmem entries */ |
| 433 | if (end <= max_low) |
| 434 | continue; |
| 435 | |
| 436 | /* Truncate partial highmem entries */ |
| 437 | if (start < max_low) |
| 438 | start = max_low; |
| 439 | |
| 440 | /* Find and exclude any reserved regions */ |
| 441 | for_each_memblock(reserved, res) { |
| 442 | unsigned long res_start, res_end; |
| 443 | |
| 444 | res_start = memblock_region_reserved_base_pfn(res); |
| 445 | res_end = memblock_region_reserved_end_pfn(res); |
| 446 | |
| 447 | if (res_end < start) |
| 448 | continue; |
| 449 | if (res_start < start) |
| 450 | res_start = start; |
| 451 | if (res_start > end) |
| 452 | res_start = end; |
| 453 | if (res_end > end) |
| 454 | res_end = end; |
| 455 | if (res_start != start) |
| 456 | free_area_high(start, res_start); |
| 457 | start = res_end; |
| 458 | if (start == end) |
| 459 | break; |
| 460 | } |
| 461 | |
| 462 | /* And now free anything which remains */ |
| 463 | if (start < end) |
| 464 | free_area_high(start, end); |
| 465 | } |
| 466 | #endif |
| 467 | } |
| 468 | |
| 469 | /* |
| 470 | * mem_init() marks the free areas in the mem_map and tells us how much |
| 471 | * memory is free. This is done after various parts of the system have |
| 472 | * claimed their memory after the kernel image. |
| 473 | */ |
| 474 | void __init mem_init(void) |
| 475 | { |
| 476 | #ifdef CONFIG_HAVE_TCM |
| 477 | /* These pointers are filled in on TCM detection */ |
| 478 | extern u32 dtcm_end; |
| 479 | extern u32 itcm_end; |
| 480 | #endif |
| 481 | |
| 482 | set_max_mapnr(pfn_to_page(max_pfn) - mem_map); |
| 483 | |
| 484 | /* this will put all unused low memory onto the freelists */ |
| 485 | free_unused_memmap(); |
| 486 | free_all_bootmem(); |
| 487 | |
| 488 | #ifdef CONFIG_SA1111 |
| 489 | /* now that our DMA memory is actually so designated, we can free it */ |
| 490 | free_reserved_area(__va(PHYS_OFFSET), swapper_pg_dir, -1, NULL); |
| 491 | #endif |
| 492 | |
| 493 | free_highpages(); |
| 494 | |
| 495 | mem_init_print_info(NULL); |
| 496 | |
| 497 | #define MLK(b, t) b, t, ((t) - (b)) >> 10 |
| 498 | #define MLM(b, t) b, t, ((t) - (b)) >> 20 |
| 499 | #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K) |
| 500 | |
| 501 | pr_notice("Virtual kernel memory layout:\n" |
| 502 | " vector : 0x%08lx - 0x%08lx (%4ld kB)\n" |
| 503 | #ifdef CONFIG_HAVE_TCM |
| 504 | " DTCM : 0x%08lx - 0x%08lx (%4ld kB)\n" |
| 505 | " ITCM : 0x%08lx - 0x%08lx (%4ld kB)\n" |
| 506 | #endif |
| 507 | " fixmap : 0x%08lx - 0x%08lx (%4ld kB)\n" |
| 508 | " vmalloc : 0x%08lx - 0x%08lx (%4ld MB)\n" |
| 509 | " lowmem : 0x%08lx - 0x%08lx (%4ld MB)\n" |
| 510 | #ifdef CONFIG_HIGHMEM |
| 511 | " pkmap : 0x%08lx - 0x%08lx (%4ld MB)\n" |
| 512 | #endif |
| 513 | #ifdef CONFIG_MODULES |
| 514 | " modules : 0x%08lx - 0x%08lx (%4ld MB)\n" |
| 515 | #endif |
| 516 | " .text : 0x%p" " - 0x%p" " (%4td kB)\n" |
| 517 | " .init : 0x%p" " - 0x%p" " (%4td kB)\n" |
| 518 | " .data : 0x%p" " - 0x%p" " (%4td kB)\n" |
| 519 | " .bss : 0x%p" " - 0x%p" " (%4td kB)\n", |
| 520 | |
| 521 | MLK(UL(CONFIG_VECTORS_BASE), UL(CONFIG_VECTORS_BASE) + |
| 522 | (PAGE_SIZE)), |
| 523 | #ifdef CONFIG_HAVE_TCM |
| 524 | MLK(DTCM_OFFSET, (unsigned long) dtcm_end), |
| 525 | MLK(ITCM_OFFSET, (unsigned long) itcm_end), |
| 526 | #endif |
| 527 | MLK(FIXADDR_START, FIXADDR_END), |
| 528 | MLM(VMALLOC_START, VMALLOC_END), |
| 529 | MLM(PAGE_OFFSET, (unsigned long)high_memory), |
| 530 | #ifdef CONFIG_HIGHMEM |
| 531 | MLM(PKMAP_BASE, (PKMAP_BASE) + (LAST_PKMAP) * |
| 532 | (PAGE_SIZE)), |
| 533 | #endif |
| 534 | #ifdef CONFIG_MODULES |
| 535 | MLM(MODULES_VADDR, MODULES_END), |
| 536 | #endif |
| 537 | |
| 538 | MLK_ROUNDUP(_text, _etext), |
| 539 | MLK_ROUNDUP(__init_begin, __init_end), |
| 540 | MLK_ROUNDUP(_sdata, _edata), |
| 541 | MLK_ROUNDUP(__bss_start, __bss_stop)); |
| 542 | |
| 543 | #undef MLK |
| 544 | #undef MLM |
| 545 | #undef MLK_ROUNDUP |
| 546 | |
| 547 | /* |
| 548 | * Check boundaries twice: Some fundamental inconsistencies can |
| 549 | * be detected at build time already. |
| 550 | */ |
| 551 | #ifdef CONFIG_MMU |
| 552 | BUILD_BUG_ON(TASK_SIZE > MODULES_VADDR); |
| 553 | BUG_ON(TASK_SIZE > MODULES_VADDR); |
| 554 | #endif |
| 555 | |
| 556 | #ifdef CONFIG_HIGHMEM |
| 557 | BUILD_BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET); |
| 558 | BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET); |
| 559 | #endif |
| 560 | |
| 561 | if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) { |
| 562 | extern int sysctl_overcommit_memory; |
| 563 | /* |
| 564 | * On a machine this small we won't get |
| 565 | * anywhere without overcommit, so turn |
| 566 | * it on by default. |
| 567 | */ |
| 568 | sysctl_overcommit_memory = OVERCOMMIT_ALWAYS; |
| 569 | } |
| 570 | } |
| 571 | |
| 572 | #ifdef CONFIG_ARM_KERNMEM_PERMS |
| 573 | struct section_perm { |
| 574 | unsigned long start; |
| 575 | unsigned long end; |
| 576 | pmdval_t mask; |
| 577 | pmdval_t prot; |
| 578 | pmdval_t clear; |
| 579 | }; |
| 580 | |
| 581 | static struct section_perm nx_perms[] = { |
| 582 | /* Make pages tables, etc before _stext RW (set NX). */ |
| 583 | { |
| 584 | .start = PAGE_OFFSET, |
| 585 | .end = (unsigned long)_stext, |
| 586 | .mask = ~PMD_SECT_XN, |
| 587 | .prot = PMD_SECT_XN, |
| 588 | }, |
| 589 | /* Make init RW (set NX). */ |
| 590 | { |
| 591 | .start = (unsigned long)__init_begin, |
| 592 | .end = (unsigned long)_sdata, |
| 593 | .mask = ~PMD_SECT_XN, |
| 594 | .prot = PMD_SECT_XN, |
| 595 | }, |
| 596 | #ifdef CONFIG_DEBUG_RODATA |
| 597 | /* Make rodata NX (set RO in ro_perms below). */ |
| 598 | { |
| 599 | .start = (unsigned long)__start_rodata, |
| 600 | .end = (unsigned long)__init_begin, |
| 601 | .mask = ~PMD_SECT_XN, |
| 602 | .prot = PMD_SECT_XN, |
| 603 | }, |
| 604 | #endif |
| 605 | }; |
| 606 | |
| 607 | #ifdef CONFIG_DEBUG_RODATA |
| 608 | static struct section_perm ro_perms[] = { |
| 609 | /* Make kernel code and rodata RX (set RO). */ |
| 610 | { |
| 611 | .start = (unsigned long)_stext, |
| 612 | .end = (unsigned long)__init_begin, |
| 613 | #ifdef CONFIG_ARM_LPAE |
| 614 | .mask = ~L_PMD_SECT_RDONLY, |
| 615 | .prot = L_PMD_SECT_RDONLY, |
| 616 | #else |
| 617 | .mask = ~(PMD_SECT_APX | PMD_SECT_AP_WRITE), |
| 618 | .prot = PMD_SECT_APX | PMD_SECT_AP_WRITE, |
| 619 | .clear = PMD_SECT_AP_WRITE, |
| 620 | #endif |
| 621 | }, |
| 622 | }; |
| 623 | #endif |
| 624 | |
| 625 | /* |
| 626 | * Updates section permissions only for the current mm (sections are |
| 627 | * copied into each mm). During startup, this is the init_mm. Is only |
| 628 | * safe to be called with preemption disabled, as under stop_machine(). |
| 629 | */ |
| 630 | static inline void section_update(unsigned long addr, pmdval_t mask, |
| 631 | pmdval_t prot, struct mm_struct *mm) |
| 632 | { |
| 633 | pmd_t *pmd; |
| 634 | |
| 635 | pmd = pmd_offset(pud_offset(pgd_offset(mm, addr), addr), addr); |
| 636 | |
| 637 | #ifdef CONFIG_ARM_LPAE |
| 638 | pmd[0] = __pmd((pmd_val(pmd[0]) & mask) | prot); |
| 639 | #else |
| 640 | if (addr & SECTION_SIZE) |
| 641 | pmd[1] = __pmd((pmd_val(pmd[1]) & mask) | prot); |
| 642 | else |
| 643 | pmd[0] = __pmd((pmd_val(pmd[0]) & mask) | prot); |
| 644 | #endif |
| 645 | flush_pmd_entry(pmd); |
| 646 | local_flush_tlb_kernel_range(addr, addr + SECTION_SIZE); |
| 647 | } |
| 648 | |
| 649 | /* Make sure extended page tables are in use. */ |
| 650 | static inline bool arch_has_strict_perms(void) |
| 651 | { |
| 652 | if (cpu_architecture() < CPU_ARCH_ARMv6) |
| 653 | return false; |
| 654 | |
| 655 | return !!(get_cr() & CR_XP); |
| 656 | } |
| 657 | |
| 658 | void set_section_perms(struct section_perm *perms, int n, bool set, |
| 659 | struct mm_struct *mm) |
| 660 | { |
| 661 | size_t i; |
| 662 | unsigned long addr; |
| 663 | |
| 664 | if (!arch_has_strict_perms()) |
| 665 | return; |
| 666 | |
| 667 | for (i = 0; i < n; i++) { |
| 668 | if (!IS_ALIGNED(perms[i].start, SECTION_SIZE) || |
| 669 | !IS_ALIGNED(perms[i].end, SECTION_SIZE)) { |
| 670 | pr_err("BUG: section %lx-%lx not aligned to %lx\n", |
| 671 | perms[i].start, perms[i].end, |
| 672 | SECTION_SIZE); |
| 673 | continue; |
| 674 | } |
| 675 | |
| 676 | for (addr = perms[i].start; |
| 677 | addr < perms[i].end; |
| 678 | addr += SECTION_SIZE) |
| 679 | section_update(addr, perms[i].mask, |
| 680 | set ? perms[i].prot : perms[i].clear, mm); |
| 681 | } |
| 682 | |
| 683 | } |
| 684 | |
| 685 | static void update_sections_early(struct section_perm perms[], int n) |
| 686 | { |
| 687 | struct task_struct *t, *s; |
| 688 | |
| 689 | read_lock(&tasklist_lock); |
| 690 | for_each_process(t) { |
| 691 | if (t->flags & PF_KTHREAD) |
| 692 | continue; |
| 693 | for_each_thread(t, s) |
| 694 | set_section_perms(perms, n, true, s->mm); |
| 695 | } |
| 696 | read_unlock(&tasklist_lock); |
| 697 | set_section_perms(perms, n, true, current->active_mm); |
| 698 | set_section_perms(perms, n, true, &init_mm); |
| 699 | } |
| 700 | |
| 701 | int __fix_kernmem_perms(void *unused) |
| 702 | { |
| 703 | update_sections_early(nx_perms, ARRAY_SIZE(nx_perms)); |
| 704 | return 0; |
| 705 | } |
| 706 | |
| 707 | void fix_kernmem_perms(void) |
| 708 | { |
| 709 | stop_machine(__fix_kernmem_perms, NULL, NULL); |
| 710 | } |
| 711 | |
| 712 | #ifdef CONFIG_DEBUG_RODATA |
| 713 | int __mark_rodata_ro(void *unused) |
| 714 | { |
| 715 | update_sections_early(ro_perms, ARRAY_SIZE(ro_perms)); |
| 716 | return 0; |
| 717 | } |
| 718 | |
| 719 | void mark_rodata_ro(void) |
| 720 | { |
| 721 | stop_machine(__mark_rodata_ro, NULL, NULL); |
| 722 | } |
| 723 | |
| 724 | void set_kernel_text_rw(void) |
| 725 | { |
| 726 | set_section_perms(ro_perms, ARRAY_SIZE(ro_perms), false, |
| 727 | current->active_mm); |
| 728 | } |
| 729 | |
| 730 | void set_kernel_text_ro(void) |
| 731 | { |
| 732 | set_section_perms(ro_perms, ARRAY_SIZE(ro_perms), true, |
| 733 | current->active_mm); |
| 734 | } |
| 735 | #endif /* CONFIG_DEBUG_RODATA */ |
| 736 | |
| 737 | #else |
| 738 | static inline void fix_kernmem_perms(void) { } |
| 739 | #endif /* CONFIG_ARM_KERNMEM_PERMS */ |
| 740 | |
| 741 | void free_tcmmem(void) |
| 742 | { |
| 743 | #ifdef CONFIG_HAVE_TCM |
| 744 | extern char __tcm_start, __tcm_end; |
| 745 | |
| 746 | poison_init_mem(&__tcm_start, &__tcm_end - &__tcm_start); |
| 747 | free_reserved_area(&__tcm_start, &__tcm_end, -1, "TCM link"); |
| 748 | #endif |
| 749 | } |
| 750 | |
| 751 | void free_initmem(void) |
| 752 | { |
| 753 | fix_kernmem_perms(); |
| 754 | free_tcmmem(); |
| 755 | |
| 756 | poison_init_mem(__init_begin, __init_end - __init_begin); |
| 757 | if (!machine_is_integrator() && !machine_is_cintegrator()) |
| 758 | free_initmem_default(-1); |
| 759 | } |
| 760 | |
| 761 | #ifdef CONFIG_BLK_DEV_INITRD |
| 762 | |
| 763 | static int keep_initrd; |
| 764 | |
| 765 | void free_initrd_mem(unsigned long start, unsigned long end) |
| 766 | { |
| 767 | if (!keep_initrd) { |
| 768 | if (start == initrd_start) |
| 769 | start = round_down(start, PAGE_SIZE); |
| 770 | if (end == initrd_end) |
| 771 | end = round_up(end, PAGE_SIZE); |
| 772 | |
| 773 | poison_init_mem((void *)start, PAGE_ALIGN(end) - start); |
| 774 | free_reserved_area((void *)start, (void *)end, -1, "initrd"); |
| 775 | } |
| 776 | } |
| 777 | |
| 778 | static int __init keepinitrd_setup(char *__unused) |
| 779 | { |
| 780 | keep_initrd = 1; |
| 781 | return 1; |
| 782 | } |
| 783 | |
| 784 | __setup("keepinitrd", keepinitrd_setup); |
| 785 | #endif |