1 /* 2 * Machine specific setup for xen 3 * 4 * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007 5 */ 6 7 #include <linux/init.h> 8 #include <linux/sched.h> 9 #include <linux/mm.h> 10 #include <linux/pm.h> 11 #include <linux/memblock.h> 12 #include <linux/cpuidle.h> 13 #include <linux/cpufreq.h> 14 15 #include <asm/elf.h> 16 #include <asm/vdso.h> 17 #include <asm/e820/api.h> 18 #include <asm/setup.h> 19 #include <asm/acpi.h> 20 #include <asm/numa.h> 21 #include <asm/xen/hypervisor.h> 22 #include <asm/xen/hypercall.h> 23 24 #include <xen/xen.h> 25 #include <xen/page.h> 26 #include <xen/interface/callback.h> 27 #include <xen/interface/memory.h> 28 #include <xen/interface/physdev.h> 29 #include <xen/features.h> 30 #include <xen/hvc-console.h> 31 #include "xen-ops.h" 32 #include "vdso.h" 33 #include "mmu.h" 34 35 #define GB(x) ((uint64_t)(x) * 1024 * 1024 * 1024) 36 37 /* Amount of extra memory space we add to the e820 ranges */ 38 struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata; 39 40 /* Number of pages released from the initial allocation. */ 41 unsigned long xen_released_pages; 42 43 /* E820 map used during setting up memory. */ 44 static struct e820_table xen_e820_table __initdata; 45 46 /* 47 * Buffer used to remap identity mapped pages. We only need the virtual space. 48 * The physical page behind this address is remapped as needed to different 49 * buffer pages. 50 */ 51 #define REMAP_SIZE (P2M_PER_PAGE - 3) 52 static struct { 53 unsigned long next_area_mfn; 54 unsigned long target_pfn; 55 unsigned long size; 56 unsigned long mfns[REMAP_SIZE]; 57 } xen_remap_buf __initdata __aligned(PAGE_SIZE); 58 static unsigned long xen_remap_mfn __initdata = INVALID_P2M_ENTRY; 59 60 /* 61 * The maximum amount of extra memory compared to the base size. The 62 * main scaling factor is the size of struct page. At extreme ratios 63 * of base:extra, all the base memory can be filled with page 64 * structures for the extra memory, leaving no space for anything 65 * else. 66 * 67 * 10x seems like a reasonable balance between scaling flexibility and 68 * leaving a practically usable system. 69 */ 70 #define EXTRA_MEM_RATIO (10) 71 72 static bool xen_512gb_limit __initdata = IS_ENABLED(CONFIG_XEN_512GB); 73 74 static void __init xen_parse_512gb(void) 75 { 76 bool val = false; 77 char *arg; 78 79 arg = strstr(xen_start_info->cmd_line, "xen_512gb_limit"); 80 if (!arg) 81 return; 82 83 arg = strstr(xen_start_info->cmd_line, "xen_512gb_limit="); 84 if (!arg) 85 val = true; 86 else if (strtobool(arg + strlen("xen_512gb_limit="), &val)) 87 return; 88 89 xen_512gb_limit = val; 90 } 91 92 static void __init xen_add_extra_mem(unsigned long start_pfn, 93 unsigned long n_pfns) 94 { 95 int i; 96 97 /* 98 * No need to check for zero size, should happen rarely and will only 99 * write a new entry regarded to be unused due to zero size. 100 */ 101 for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) { 102 /* Add new region. */ 103 if (xen_extra_mem[i].n_pfns == 0) { 104 xen_extra_mem[i].start_pfn = start_pfn; 105 xen_extra_mem[i].n_pfns = n_pfns; 106 break; 107 } 108 /* Append to existing region. */ 109 if (xen_extra_mem[i].start_pfn + xen_extra_mem[i].n_pfns == 110 start_pfn) { 111 xen_extra_mem[i].n_pfns += n_pfns; 112 break; 113 } 114 } 115 if (i == XEN_EXTRA_MEM_MAX_REGIONS) 116 printk(KERN_WARNING "Warning: not enough extra memory regions\n"); 117 118 memblock_reserve(PFN_PHYS(start_pfn), PFN_PHYS(n_pfns)); 119 } 120 121 static void __init xen_del_extra_mem(unsigned long start_pfn, 122 unsigned long n_pfns) 123 { 124 int i; 125 unsigned long start_r, size_r; 126 127 for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) { 128 start_r = xen_extra_mem[i].start_pfn; 129 size_r = xen_extra_mem[i].n_pfns; 130 131 /* Start of region. */ 132 if (start_r == start_pfn) { 133 BUG_ON(n_pfns > size_r); 134 xen_extra_mem[i].start_pfn += n_pfns; 135 xen_extra_mem[i].n_pfns -= n_pfns; 136 break; 137 } 138 /* End of region. */ 139 if (start_r + size_r == start_pfn + n_pfns) { 140 BUG_ON(n_pfns > size_r); 141 xen_extra_mem[i].n_pfns -= n_pfns; 142 break; 143 } 144 /* Mid of region. */ 145 if (start_pfn > start_r && start_pfn < start_r + size_r) { 146 BUG_ON(start_pfn + n_pfns > start_r + size_r); 147 xen_extra_mem[i].n_pfns = start_pfn - start_r; 148 /* Calling memblock_reserve() again is okay. */ 149 xen_add_extra_mem(start_pfn + n_pfns, start_r + size_r - 150 (start_pfn + n_pfns)); 151 break; 152 } 153 } 154 memblock_free(PFN_PHYS(start_pfn), PFN_PHYS(n_pfns)); 155 } 156 157 /* 158 * Called during boot before the p2m list can take entries beyond the 159 * hypervisor supplied p2m list. Entries in extra mem are to be regarded as 160 * invalid. 161 */ 162 unsigned long __ref xen_chk_extra_mem(unsigned long pfn) 163 { 164 int i; 165 166 for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) { 167 if (pfn >= xen_extra_mem[i].start_pfn && 168 pfn < xen_extra_mem[i].start_pfn + xen_extra_mem[i].n_pfns) 169 return INVALID_P2M_ENTRY; 170 } 171 172 return IDENTITY_FRAME(pfn); 173 } 174 175 /* 176 * Mark all pfns of extra mem as invalid in p2m list. 177 */ 178 void __init xen_inv_extra_mem(void) 179 { 180 unsigned long pfn, pfn_s, pfn_e; 181 int i; 182 183 for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) { 184 if (!xen_extra_mem[i].n_pfns) 185 continue; 186 pfn_s = xen_extra_mem[i].start_pfn; 187 pfn_e = pfn_s + xen_extra_mem[i].n_pfns; 188 for (pfn = pfn_s; pfn < pfn_e; pfn++) 189 set_phys_to_machine(pfn, INVALID_P2M_ENTRY); 190 } 191 } 192 193 /* 194 * Finds the next RAM pfn available in the E820 map after min_pfn. 195 * This function updates min_pfn with the pfn found and returns 196 * the size of that range or zero if not found. 197 */ 198 static unsigned long __init xen_find_pfn_range(unsigned long *min_pfn) 199 { 200 const struct e820_entry *entry = xen_e820_table.entries; 201 unsigned int i; 202 unsigned long done = 0; 203 204 for (i = 0; i < xen_e820_table.nr_entries; i++, entry++) { 205 unsigned long s_pfn; 206 unsigned long e_pfn; 207 208 if (entry->type != E820_TYPE_RAM) 209 continue; 210 211 e_pfn = PFN_DOWN(entry->addr + entry->size); 212 213 /* We only care about E820 after this */ 214 if (e_pfn <= *min_pfn) 215 continue; 216 217 s_pfn = PFN_UP(entry->addr); 218 219 /* If min_pfn falls within the E820 entry, we want to start 220 * at the min_pfn PFN. 221 */ 222 if (s_pfn <= *min_pfn) { 223 done = e_pfn - *min_pfn; 224 } else { 225 done = e_pfn - s_pfn; 226 *min_pfn = s_pfn; 227 } 228 break; 229 } 230 231 return done; 232 } 233 234 static int __init xen_free_mfn(unsigned long mfn) 235 { 236 struct xen_memory_reservation reservation = { 237 .address_bits = 0, 238 .extent_order = 0, 239 .domid = DOMID_SELF 240 }; 241 242 set_xen_guest_handle(reservation.extent_start, &mfn); 243 reservation.nr_extents = 1; 244 245 return HYPERVISOR_memory_op(XENMEM_decrease_reservation, &reservation); 246 } 247 248 /* 249 * This releases a chunk of memory and then does the identity map. It's used 250 * as a fallback if the remapping fails. 251 */ 252 static void __init xen_set_identity_and_release_chunk(unsigned long start_pfn, 253 unsigned long end_pfn, unsigned long nr_pages) 254 { 255 unsigned long pfn, end; 256 int ret; 257 258 WARN_ON(start_pfn > end_pfn); 259 260 /* Release pages first. */ 261 end = min(end_pfn, nr_pages); 262 for (pfn = start_pfn; pfn < end; pfn++) { 263 unsigned long mfn = pfn_to_mfn(pfn); 264 265 /* Make sure pfn exists to start with */ 266 if (mfn == INVALID_P2M_ENTRY || mfn_to_pfn(mfn) != pfn) 267 continue; 268 269 ret = xen_free_mfn(mfn); 270 WARN(ret != 1, "Failed to release pfn %lx err=%d\n", pfn, ret); 271 272 if (ret == 1) { 273 xen_released_pages++; 274 if (!__set_phys_to_machine(pfn, INVALID_P2M_ENTRY)) 275 break; 276 } else 277 break; 278 } 279 280 set_phys_range_identity(start_pfn, end_pfn); 281 } 282 283 /* 284 * Helper function to update the p2m and m2p tables and kernel mapping. 285 */ 286 static void __init xen_update_mem_tables(unsigned long pfn, unsigned long mfn) 287 { 288 struct mmu_update update = { 289 .ptr = ((uint64_t)mfn << PAGE_SHIFT) | MMU_MACHPHYS_UPDATE, 290 .val = pfn 291 }; 292 293 /* Update p2m */ 294 if (!set_phys_to_machine(pfn, mfn)) { 295 WARN(1, "Failed to set p2m mapping for pfn=%ld mfn=%ld\n", 296 pfn, mfn); 297 BUG(); 298 } 299 300 /* Update m2p */ 301 if (HYPERVISOR_mmu_update(&update, 1, NULL, DOMID_SELF) < 0) { 302 WARN(1, "Failed to set m2p mapping for mfn=%ld pfn=%ld\n", 303 mfn, pfn); 304 BUG(); 305 } 306 307 /* Update kernel mapping, but not for highmem. */ 308 if (pfn >= PFN_UP(__pa(high_memory - 1))) 309 return; 310 311 if (HYPERVISOR_update_va_mapping((unsigned long)__va(pfn << PAGE_SHIFT), 312 mfn_pte(mfn, PAGE_KERNEL), 0)) { 313 WARN(1, "Failed to update kernel mapping for mfn=%ld pfn=%ld\n", 314 mfn, pfn); 315 BUG(); 316 } 317 } 318 319 /* 320 * This function updates the p2m and m2p tables with an identity map from 321 * start_pfn to start_pfn+size and prepares remapping the underlying RAM of the 322 * original allocation at remap_pfn. The information needed for remapping is 323 * saved in the memory itself to avoid the need for allocating buffers. The 324 * complete remap information is contained in a list of MFNs each containing 325 * up to REMAP_SIZE MFNs and the start target PFN for doing the remap. 326 * This enables us to preserve the original mfn sequence while doing the 327 * remapping at a time when the memory management is capable of allocating 328 * virtual and physical memory in arbitrary amounts, see 'xen_remap_memory' and 329 * its callers. 330 */ 331 static void __init xen_do_set_identity_and_remap_chunk( 332 unsigned long start_pfn, unsigned long size, unsigned long remap_pfn) 333 { 334 unsigned long buf = (unsigned long)&xen_remap_buf; 335 unsigned long mfn_save, mfn; 336 unsigned long ident_pfn_iter, remap_pfn_iter; 337 unsigned long ident_end_pfn = start_pfn + size; 338 unsigned long left = size; 339 unsigned int i, chunk; 340 341 WARN_ON(size == 0); 342 343 BUG_ON(xen_feature(XENFEAT_auto_translated_physmap)); 344 345 mfn_save = virt_to_mfn(buf); 346 347 for (ident_pfn_iter = start_pfn, remap_pfn_iter = remap_pfn; 348 ident_pfn_iter < ident_end_pfn; 349 ident_pfn_iter += REMAP_SIZE, remap_pfn_iter += REMAP_SIZE) { 350 chunk = (left < REMAP_SIZE) ? left : REMAP_SIZE; 351 352 /* Map first pfn to xen_remap_buf */ 353 mfn = pfn_to_mfn(ident_pfn_iter); 354 set_pte_mfn(buf, mfn, PAGE_KERNEL); 355 356 /* Save mapping information in page */ 357 xen_remap_buf.next_area_mfn = xen_remap_mfn; 358 xen_remap_buf.target_pfn = remap_pfn_iter; 359 xen_remap_buf.size = chunk; 360 for (i = 0; i < chunk; i++) 361 xen_remap_buf.mfns[i] = pfn_to_mfn(ident_pfn_iter + i); 362 363 /* Put remap buf into list. */ 364 xen_remap_mfn = mfn; 365 366 /* Set identity map */ 367 set_phys_range_identity(ident_pfn_iter, ident_pfn_iter + chunk); 368 369 left -= chunk; 370 } 371 372 /* Restore old xen_remap_buf mapping */ 373 set_pte_mfn(buf, mfn_save, PAGE_KERNEL); 374 } 375 376 /* 377 * This function takes a contiguous pfn range that needs to be identity mapped 378 * and: 379 * 380 * 1) Finds a new range of pfns to use to remap based on E820 and remap_pfn. 381 * 2) Calls the do_ function to actually do the mapping/remapping work. 382 * 383 * The goal is to not allocate additional memory but to remap the existing 384 * pages. In the case of an error the underlying memory is simply released back 385 * to Xen and not remapped. 386 */ 387 static unsigned long __init xen_set_identity_and_remap_chunk( 388 unsigned long start_pfn, unsigned long end_pfn, unsigned long nr_pages, 389 unsigned long remap_pfn) 390 { 391 unsigned long pfn; 392 unsigned long i = 0; 393 unsigned long n = end_pfn - start_pfn; 394 395 if (remap_pfn == 0) 396 remap_pfn = nr_pages; 397 398 while (i < n) { 399 unsigned long cur_pfn = start_pfn + i; 400 unsigned long left = n - i; 401 unsigned long size = left; 402 unsigned long remap_range_size; 403 404 /* Do not remap pages beyond the current allocation */ 405 if (cur_pfn >= nr_pages) { 406 /* Identity map remaining pages */ 407 set_phys_range_identity(cur_pfn, cur_pfn + size); 408 break; 409 } 410 if (cur_pfn + size > nr_pages) 411 size = nr_pages - cur_pfn; 412 413 remap_range_size = xen_find_pfn_range(&remap_pfn); 414 if (!remap_range_size) { 415 pr_warning("Unable to find available pfn range, not remapping identity pages\n"); 416 xen_set_identity_and_release_chunk(cur_pfn, 417 cur_pfn + left, nr_pages); 418 break; 419 } 420 /* Adjust size to fit in current e820 RAM region */ 421 if (size > remap_range_size) 422 size = remap_range_size; 423 424 xen_do_set_identity_and_remap_chunk(cur_pfn, size, remap_pfn); 425 426 /* Update variables to reflect new mappings. */ 427 i += size; 428 remap_pfn += size; 429 } 430 431 /* 432 * If the PFNs are currently mapped, the VA mapping also needs 433 * to be updated to be 1:1. 434 */ 435 for (pfn = start_pfn; pfn <= max_pfn_mapped && pfn < end_pfn; pfn++) 436 (void)HYPERVISOR_update_va_mapping( 437 (unsigned long)__va(pfn << PAGE_SHIFT), 438 mfn_pte(pfn, PAGE_KERNEL_IO), 0); 439 440 return remap_pfn; 441 } 442 443 static unsigned long __init xen_count_remap_pages( 444 unsigned long start_pfn, unsigned long end_pfn, unsigned long nr_pages, 445 unsigned long remap_pages) 446 { 447 if (start_pfn >= nr_pages) 448 return remap_pages; 449 450 return remap_pages + min(end_pfn, nr_pages) - start_pfn; 451 } 452 453 static unsigned long __init xen_foreach_remap_area(unsigned long nr_pages, 454 unsigned long (*func)(unsigned long start_pfn, unsigned long end_pfn, 455 unsigned long nr_pages, unsigned long last_val)) 456 { 457 phys_addr_t start = 0; 458 unsigned long ret_val = 0; 459 const struct e820_entry *entry = xen_e820_table.entries; 460 int i; 461 462 /* 463 * Combine non-RAM regions and gaps until a RAM region (or the 464 * end of the map) is reached, then call the provided function 465 * to perform its duty on the non-RAM region. 466 * 467 * The combined non-RAM regions are rounded to a whole number 468 * of pages so any partial pages are accessible via the 1:1 469 * mapping. This is needed for some BIOSes that put (for 470 * example) the DMI tables in a reserved region that begins on 471 * a non-page boundary. 472 */ 473 for (i = 0; i < xen_e820_table.nr_entries; i++, entry++) { 474 phys_addr_t end = entry->addr + entry->size; 475 if (entry->type == E820_TYPE_RAM || i == xen_e820_table.nr_entries - 1) { 476 unsigned long start_pfn = PFN_DOWN(start); 477 unsigned long end_pfn = PFN_UP(end); 478 479 if (entry->type == E820_TYPE_RAM) 480 end_pfn = PFN_UP(entry->addr); 481 482 if (start_pfn < end_pfn) 483 ret_val = func(start_pfn, end_pfn, nr_pages, 484 ret_val); 485 start = end; 486 } 487 } 488 489 return ret_val; 490 } 491 492 /* 493 * Remap the memory prepared in xen_do_set_identity_and_remap_chunk(). 494 * The remap information (which mfn remap to which pfn) is contained in the 495 * to be remapped memory itself in a linked list anchored at xen_remap_mfn. 496 * This scheme allows to remap the different chunks in arbitrary order while 497 * the resulting mapping will be independant from the order. 498 */ 499 void __init xen_remap_memory(void) 500 { 501 unsigned long buf = (unsigned long)&xen_remap_buf; 502 unsigned long mfn_save, pfn; 503 unsigned long remapped = 0; 504 unsigned int i; 505 unsigned long pfn_s = ~0UL; 506 unsigned long len = 0; 507 508 mfn_save = virt_to_mfn(buf); 509 510 while (xen_remap_mfn != INVALID_P2M_ENTRY) { 511 /* Map the remap information */ 512 set_pte_mfn(buf, xen_remap_mfn, PAGE_KERNEL); 513 514 BUG_ON(xen_remap_mfn != xen_remap_buf.mfns[0]); 515 516 pfn = xen_remap_buf.target_pfn; 517 for (i = 0; i < xen_remap_buf.size; i++) { 518 xen_update_mem_tables(pfn, xen_remap_buf.mfns[i]); 519 remapped++; 520 pfn++; 521 } 522 if (pfn_s == ~0UL || pfn == pfn_s) { 523 pfn_s = xen_remap_buf.target_pfn; 524 len += xen_remap_buf.size; 525 } else if (pfn_s + len == xen_remap_buf.target_pfn) { 526 len += xen_remap_buf.size; 527 } else { 528 xen_del_extra_mem(pfn_s, len); 529 pfn_s = xen_remap_buf.target_pfn; 530 len = xen_remap_buf.size; 531 } 532 xen_remap_mfn = xen_remap_buf.next_area_mfn; 533 } 534 535 if (pfn_s != ~0UL && len) 536 xen_del_extra_mem(pfn_s, len); 537 538 set_pte_mfn(buf, mfn_save, PAGE_KERNEL); 539 540 pr_info("Remapped %ld page(s)\n", remapped); 541 } 542 543 static unsigned long __init xen_get_pages_limit(void) 544 { 545 unsigned long limit; 546 547 #ifdef CONFIG_X86_32 548 limit = GB(64) / PAGE_SIZE; 549 #else 550 limit = MAXMEM / PAGE_SIZE; 551 if (!xen_initial_domain() && xen_512gb_limit) 552 limit = GB(512) / PAGE_SIZE; 553 #endif 554 return limit; 555 } 556 557 static unsigned long __init xen_get_max_pages(void) 558 { 559 unsigned long max_pages, limit; 560 domid_t domid = DOMID_SELF; 561 long ret; 562 563 limit = xen_get_pages_limit(); 564 max_pages = limit; 565 566 /* 567 * For the initial domain we use the maximum reservation as 568 * the maximum page. 569 * 570 * For guest domains the current maximum reservation reflects 571 * the current maximum rather than the static maximum. In this 572 * case the e820 map provided to us will cover the static 573 * maximum region. 574 */ 575 if (xen_initial_domain()) { 576 ret = HYPERVISOR_memory_op(XENMEM_maximum_reservation, &domid); 577 if (ret > 0) 578 max_pages = ret; 579 } 580 581 return min(max_pages, limit); 582 } 583 584 static void __init xen_align_and_add_e820_region(phys_addr_t start, 585 phys_addr_t size, int type) 586 { 587 phys_addr_t end = start + size; 588 589 /* Align RAM regions to page boundaries. */ 590 if (type == E820_TYPE_RAM) { 591 start = PAGE_ALIGN(start); 592 end &= ~((phys_addr_t)PAGE_SIZE - 1); 593 } 594 595 e820__range_add(start, end - start, type); 596 } 597 598 static void __init xen_ignore_unusable(void) 599 { 600 struct e820_entry *entry = xen_e820_table.entries; 601 unsigned int i; 602 603 for (i = 0; i < xen_e820_table.nr_entries; i++, entry++) { 604 if (entry->type == E820_TYPE_UNUSABLE) 605 entry->type = E820_TYPE_RAM; 606 } 607 } 608 609 bool __init xen_is_e820_reserved(phys_addr_t start, phys_addr_t size) 610 { 611 struct e820_entry *entry; 612 unsigned mapcnt; 613 phys_addr_t end; 614 615 if (!size) 616 return false; 617 618 end = start + size; 619 entry = xen_e820_table.entries; 620 621 for (mapcnt = 0; mapcnt < xen_e820_table.nr_entries; mapcnt++) { 622 if (entry->type == E820_TYPE_RAM && entry->addr <= start && 623 (entry->addr + entry->size) >= end) 624 return false; 625 626 entry++; 627 } 628 629 return true; 630 } 631 632 /* 633 * Find a free area in physical memory not yet reserved and compliant with 634 * E820 map. 635 * Used to relocate pre-allocated areas like initrd or p2m list which are in 636 * conflict with the to be used E820 map. 637 * In case no area is found, return 0. Otherwise return the physical address 638 * of the area which is already reserved for convenience. 639 */ 640 phys_addr_t __init xen_find_free_area(phys_addr_t size) 641 { 642 unsigned mapcnt; 643 phys_addr_t addr, start; 644 struct e820_entry *entry = xen_e820_table.entries; 645 646 for (mapcnt = 0; mapcnt < xen_e820_table.nr_entries; mapcnt++, entry++) { 647 if (entry->type != E820_TYPE_RAM || entry->size < size) 648 continue; 649 start = entry->addr; 650 for (addr = start; addr < start + size; addr += PAGE_SIZE) { 651 if (!memblock_is_reserved(addr)) 652 continue; 653 start = addr + PAGE_SIZE; 654 if (start + size > entry->addr + entry->size) 655 break; 656 } 657 if (addr >= start + size) { 658 memblock_reserve(start, size); 659 return start; 660 } 661 } 662 663 return 0; 664 } 665 666 /* 667 * Like memcpy, but with physical addresses for dest and src. 668 */ 669 static void __init xen_phys_memcpy(phys_addr_t dest, phys_addr_t src, 670 phys_addr_t n) 671 { 672 phys_addr_t dest_off, src_off, dest_len, src_len, len; 673 void *from, *to; 674 675 while (n) { 676 dest_off = dest & ~PAGE_MASK; 677 src_off = src & ~PAGE_MASK; 678 dest_len = n; 679 if (dest_len > (NR_FIX_BTMAPS << PAGE_SHIFT) - dest_off) 680 dest_len = (NR_FIX_BTMAPS << PAGE_SHIFT) - dest_off; 681 src_len = n; 682 if (src_len > (NR_FIX_BTMAPS << PAGE_SHIFT) - src_off) 683 src_len = (NR_FIX_BTMAPS << PAGE_SHIFT) - src_off; 684 len = min(dest_len, src_len); 685 to = early_memremap(dest - dest_off, dest_len + dest_off); 686 from = early_memremap(src - src_off, src_len + src_off); 687 memcpy(to, from, len); 688 early_memunmap(to, dest_len + dest_off); 689 early_memunmap(from, src_len + src_off); 690 n -= len; 691 dest += len; 692 src += len; 693 } 694 } 695 696 /* 697 * Reserve Xen mfn_list. 698 */ 699 static void __init xen_reserve_xen_mfnlist(void) 700 { 701 phys_addr_t start, size; 702 703 if (xen_start_info->mfn_list >= __START_KERNEL_map) { 704 start = __pa(xen_start_info->mfn_list); 705 size = PFN_ALIGN(xen_start_info->nr_pages * 706 sizeof(unsigned long)); 707 } else { 708 start = PFN_PHYS(xen_start_info->first_p2m_pfn); 709 size = PFN_PHYS(xen_start_info->nr_p2m_frames); 710 } 711 712 memblock_reserve(start, size); 713 if (!xen_is_e820_reserved(start, size)) 714 return; 715 716 #ifdef CONFIG_X86_32 717 /* 718 * Relocating the p2m on 32 bit system to an arbitrary virtual address 719 * is not supported, so just give up. 720 */ 721 xen_raw_console_write("Xen hypervisor allocated p2m list conflicts with E820 map\n"); 722 BUG(); 723 #else 724 xen_relocate_p2m(); 725 memblock_free(start, size); 726 #endif 727 } 728 729 /** 730 * machine_specific_memory_setup - Hook for machine specific memory setup. 731 **/ 732 char * __init xen_memory_setup(void) 733 { 734 unsigned long max_pfn, pfn_s, n_pfns; 735 phys_addr_t mem_end, addr, size, chunk_size; 736 u32 type; 737 int rc; 738 struct xen_memory_map memmap; 739 unsigned long max_pages; 740 unsigned long extra_pages = 0; 741 int i; 742 int op; 743 744 xen_parse_512gb(); 745 max_pfn = xen_get_pages_limit(); 746 max_pfn = min(max_pfn, xen_start_info->nr_pages); 747 mem_end = PFN_PHYS(max_pfn); 748 749 memmap.nr_entries = ARRAY_SIZE(xen_e820_table.entries); 750 set_xen_guest_handle(memmap.buffer, xen_e820_table.entries); 751 752 op = xen_initial_domain() ? 753 XENMEM_machine_memory_map : 754 XENMEM_memory_map; 755 rc = HYPERVISOR_memory_op(op, &memmap); 756 if (rc == -ENOSYS) { 757 BUG_ON(xen_initial_domain()); 758 memmap.nr_entries = 1; 759 xen_e820_table.entries[0].addr = 0ULL; 760 xen_e820_table.entries[0].size = mem_end; 761 /* 8MB slack (to balance backend allocations). */ 762 xen_e820_table.entries[0].size += 8ULL << 20; 763 xen_e820_table.entries[0].type = E820_TYPE_RAM; 764 rc = 0; 765 } 766 BUG_ON(rc); 767 BUG_ON(memmap.nr_entries == 0); 768 xen_e820_table.nr_entries = memmap.nr_entries; 769 770 /* 771 * Xen won't allow a 1:1 mapping to be created to UNUSABLE 772 * regions, so if we're using the machine memory map leave the 773 * region as RAM as it is in the pseudo-physical map. 774 * 775 * UNUSABLE regions in domUs are not handled and will need 776 * a patch in the future. 777 */ 778 if (xen_initial_domain()) 779 xen_ignore_unusable(); 780 781 /* Make sure the Xen-supplied memory map is well-ordered. */ 782 e820__update_table(&xen_e820_table); 783 784 max_pages = xen_get_max_pages(); 785 786 /* How many extra pages do we need due to remapping? */ 787 max_pages += xen_foreach_remap_area(max_pfn, xen_count_remap_pages); 788 789 if (max_pages > max_pfn) 790 extra_pages += max_pages - max_pfn; 791 792 /* 793 * Clamp the amount of extra memory to a EXTRA_MEM_RATIO 794 * factor the base size. On non-highmem systems, the base 795 * size is the full initial memory allocation; on highmem it 796 * is limited to the max size of lowmem, so that it doesn't 797 * get completely filled. 798 * 799 * Make sure we have no memory above max_pages, as this area 800 * isn't handled by the p2m management. 801 * 802 * In principle there could be a problem in lowmem systems if 803 * the initial memory is also very large with respect to 804 * lowmem, but we won't try to deal with that here. 805 */ 806 extra_pages = min3(EXTRA_MEM_RATIO * min(max_pfn, PFN_DOWN(MAXMEM)), 807 extra_pages, max_pages - max_pfn); 808 i = 0; 809 addr = xen_e820_table.entries[0].addr; 810 size = xen_e820_table.entries[0].size; 811 while (i < xen_e820_table.nr_entries) { 812 bool discard = false; 813 814 chunk_size = size; 815 type = xen_e820_table.entries[i].type; 816 817 if (type == E820_TYPE_RAM) { 818 if (addr < mem_end) { 819 chunk_size = min(size, mem_end - addr); 820 } else if (extra_pages) { 821 chunk_size = min(size, PFN_PHYS(extra_pages)); 822 pfn_s = PFN_UP(addr); 823 n_pfns = PFN_DOWN(addr + chunk_size) - pfn_s; 824 extra_pages -= n_pfns; 825 xen_add_extra_mem(pfn_s, n_pfns); 826 xen_max_p2m_pfn = pfn_s + n_pfns; 827 } else 828 discard = true; 829 } 830 831 if (!discard) 832 xen_align_and_add_e820_region(addr, chunk_size, type); 833 834 addr += chunk_size; 835 size -= chunk_size; 836 if (size == 0) { 837 i++; 838 if (i < xen_e820_table.nr_entries) { 839 addr = xen_e820_table.entries[i].addr; 840 size = xen_e820_table.entries[i].size; 841 } 842 } 843 } 844 845 /* 846 * Set the rest as identity mapped, in case PCI BARs are 847 * located here. 848 */ 849 set_phys_range_identity(addr / PAGE_SIZE, ~0ul); 850 851 /* 852 * In domU, the ISA region is normal, usable memory, but we 853 * reserve ISA memory anyway because too many things poke 854 * about in there. 855 */ 856 e820__range_add(ISA_START_ADDRESS, ISA_END_ADDRESS - ISA_START_ADDRESS, E820_TYPE_RESERVED); 857 858 e820__update_table(e820_table); 859 860 /* 861 * Check whether the kernel itself conflicts with the target E820 map. 862 * Failing now is better than running into weird problems later due 863 * to relocating (and even reusing) pages with kernel text or data. 864 */ 865 if (xen_is_e820_reserved(__pa_symbol(_text), 866 __pa_symbol(__bss_stop) - __pa_symbol(_text))) { 867 xen_raw_console_write("Xen hypervisor allocated kernel memory conflicts with E820 map\n"); 868 BUG(); 869 } 870 871 /* 872 * Check for a conflict of the hypervisor supplied page tables with 873 * the target E820 map. 874 */ 875 xen_pt_check_e820(); 876 877 xen_reserve_xen_mfnlist(); 878 879 /* Check for a conflict of the initrd with the target E820 map. */ 880 if (xen_is_e820_reserved(boot_params.hdr.ramdisk_image, 881 boot_params.hdr.ramdisk_size)) { 882 phys_addr_t new_area, start, size; 883 884 new_area = xen_find_free_area(boot_params.hdr.ramdisk_size); 885 if (!new_area) { 886 xen_raw_console_write("Can't find new memory area for initrd needed due to E820 map conflict\n"); 887 BUG(); 888 } 889 890 start = boot_params.hdr.ramdisk_image; 891 size = boot_params.hdr.ramdisk_size; 892 xen_phys_memcpy(new_area, start, size); 893 pr_info("initrd moved from [mem %#010llx-%#010llx] to [mem %#010llx-%#010llx]\n", 894 start, start + size, new_area, new_area + size); 895 memblock_free(start, size); 896 boot_params.hdr.ramdisk_image = new_area; 897 boot_params.ext_ramdisk_image = new_area >> 32; 898 } 899 900 /* 901 * Set identity map on non-RAM pages and prepare remapping the 902 * underlying RAM. 903 */ 904 xen_foreach_remap_area(max_pfn, xen_set_identity_and_remap_chunk); 905 906 pr_info("Released %ld page(s)\n", xen_released_pages); 907 908 return "Xen"; 909 } 910 911 /* 912 * Machine specific memory setup for auto-translated guests. 913 */ 914 char * __init xen_auto_xlated_memory_setup(void) 915 { 916 struct xen_memory_map memmap; 917 int i; 918 int rc; 919 920 memmap.nr_entries = ARRAY_SIZE(xen_e820_table.entries); 921 set_xen_guest_handle(memmap.buffer, xen_e820_table.entries); 922 923 rc = HYPERVISOR_memory_op(XENMEM_memory_map, &memmap); 924 if (rc < 0) 925 panic("No memory map (%d)\n", rc); 926 927 xen_e820_table.nr_entries = memmap.nr_entries; 928 929 e820__update_table(&xen_e820_table); 930 931 for (i = 0; i < xen_e820_table.nr_entries; i++) 932 e820__range_add(xen_e820_table.entries[i].addr, xen_e820_table.entries[i].size, xen_e820_table.entries[i].type); 933 934 /* Remove p2m info, it is not needed. */ 935 xen_start_info->mfn_list = 0; 936 xen_start_info->first_p2m_pfn = 0; 937 xen_start_info->nr_p2m_frames = 0; 938 939 return "Xen"; 940 } 941 942 /* 943 * Set the bit indicating "nosegneg" library variants should be used. 944 * We only need to bother in pure 32-bit mode; compat 32-bit processes 945 * can have un-truncated segments, so wrapping around is allowed. 946 */ 947 static void __init fiddle_vdso(void) 948 { 949 #ifdef CONFIG_X86_32 950 u32 *mask = vdso_image_32.data + 951 vdso_image_32.sym_VDSO32_NOTE_MASK; 952 *mask |= 1 << VDSO_NOTE_NONEGSEG_BIT; 953 #endif 954 } 955 956 static int register_callback(unsigned type, const void *func) 957 { 958 struct callback_register callback = { 959 .type = type, 960 .address = XEN_CALLBACK(__KERNEL_CS, func), 961 .flags = CALLBACKF_mask_events, 962 }; 963 964 return HYPERVISOR_callback_op(CALLBACKOP_register, &callback); 965 } 966 967 void xen_enable_sysenter(void) 968 { 969 int ret; 970 unsigned sysenter_feature; 971 972 #ifdef CONFIG_X86_32 973 sysenter_feature = X86_FEATURE_SEP; 974 #else 975 sysenter_feature = X86_FEATURE_SYSENTER32; 976 #endif 977 978 if (!boot_cpu_has(sysenter_feature)) 979 return; 980 981 ret = register_callback(CALLBACKTYPE_sysenter, xen_sysenter_target); 982 if(ret != 0) 983 setup_clear_cpu_cap(sysenter_feature); 984 } 985 986 void xen_enable_syscall(void) 987 { 988 #ifdef CONFIG_X86_64 989 int ret; 990 991 ret = register_callback(CALLBACKTYPE_syscall, xen_syscall_target); 992 if (ret != 0) { 993 printk(KERN_ERR "Failed to set syscall callback: %d\n", ret); 994 /* Pretty fatal; 64-bit userspace has no other 995 mechanism for syscalls. */ 996 } 997 998 if (boot_cpu_has(X86_FEATURE_SYSCALL32)) { 999 ret = register_callback(CALLBACKTYPE_syscall32, 1000 xen_syscall32_target); 1001 if (ret != 0) 1002 setup_clear_cpu_cap(X86_FEATURE_SYSCALL32); 1003 } 1004 #endif /* CONFIG_X86_64 */ 1005 } 1006 1007 void __init xen_pvmmu_arch_setup(void) 1008 { 1009 HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_4gb_segments); 1010 HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_writable_pagetables); 1011 1012 HYPERVISOR_vm_assist(VMASST_CMD_enable, 1013 VMASST_TYPE_pae_extended_cr3); 1014 1015 if (register_callback(CALLBACKTYPE_event, xen_hypervisor_callback) || 1016 register_callback(CALLBACKTYPE_failsafe, xen_failsafe_callback)) 1017 BUG(); 1018 1019 xen_enable_sysenter(); 1020 xen_enable_syscall(); 1021 } 1022 1023 /* This function is not called for HVM domains */ 1024 void __init xen_arch_setup(void) 1025 { 1026 xen_panic_handler_init(); 1027 if (!xen_feature(XENFEAT_auto_translated_physmap)) 1028 xen_pvmmu_arch_setup(); 1029 1030 #ifdef CONFIG_ACPI 1031 if (!(xen_start_info->flags & SIF_INITDOMAIN)) { 1032 printk(KERN_INFO "ACPI in unprivileged domain disabled\n"); 1033 disable_acpi(); 1034 } 1035 #endif 1036 1037 memcpy(boot_command_line, xen_start_info->cmd_line, 1038 MAX_GUEST_CMDLINE > COMMAND_LINE_SIZE ? 1039 COMMAND_LINE_SIZE : MAX_GUEST_CMDLINE); 1040 1041 /* Set up idle, making sure it calls safe_halt() pvop */ 1042 disable_cpuidle(); 1043 disable_cpufreq(); 1044 WARN_ON(xen_set_default_idle()); 1045 fiddle_vdso(); 1046 #ifdef CONFIG_NUMA 1047 numa_off = 1; 1048 #endif 1049 } 1050