1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Machine specific setup for xen 4 * 5 * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007 6 */ 7 8 #include <linux/init.h> 9 #include <linux/sched.h> 10 #include <linux/kstrtox.h> 11 #include <linux/mm.h> 12 #include <linux/pm.h> 13 #include <linux/memblock.h> 14 #include <linux/cpuidle.h> 15 #include <linux/cpufreq.h> 16 #include <linux/memory_hotplug.h> 17 18 #include <asm/elf.h> 19 #include <asm/vdso.h> 20 #include <asm/e820/api.h> 21 #include <asm/setup.h> 22 #include <asm/acpi.h> 23 #include <asm/numa.h> 24 #include <asm/idtentry.h> 25 #include <asm/xen/hypervisor.h> 26 #include <asm/xen/hypercall.h> 27 28 #include <xen/xen.h> 29 #include <xen/page.h> 30 #include <xen/interface/callback.h> 31 #include <xen/interface/memory.h> 32 #include <xen/interface/physdev.h> 33 #include <xen/features.h> 34 #include <xen/hvc-console.h> 35 #include "xen-ops.h" 36 #include "mmu.h" 37 38 #define GB(x) ((uint64_t)(x) * 1024 * 1024 * 1024) 39 40 /* Amount of extra memory space we add to the e820 ranges */ 41 struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata; 42 43 /* Number of pages released from the initial allocation. */ 44 unsigned long xen_released_pages; 45 46 /* E820 map used during setting up memory. */ 47 static struct e820_table xen_e820_table __initdata; 48 49 /* 50 * Buffer used to remap identity mapped pages. We only need the virtual space. 51 * The physical page behind this address is remapped as needed to different 52 * buffer pages. 53 */ 54 #define REMAP_SIZE (P2M_PER_PAGE - 3) 55 static struct { 56 unsigned long next_area_mfn; 57 unsigned long target_pfn; 58 unsigned long size; 59 unsigned long mfns[REMAP_SIZE]; 60 } xen_remap_buf __initdata __aligned(PAGE_SIZE); 61 static unsigned long xen_remap_mfn __initdata = INVALID_P2M_ENTRY; 62 63 /* 64 * The maximum amount of extra memory compared to the base size. The 65 * main scaling factor is the size of struct page. At extreme ratios 66 * of base:extra, all the base memory can be filled with page 67 * structures for the extra memory, leaving no space for anything 68 * else. 69 * 70 * 10x seems like a reasonable balance between scaling flexibility and 71 * leaving a practically usable system. 72 */ 73 #define EXTRA_MEM_RATIO (10) 74 75 static bool xen_512gb_limit __initdata = IS_ENABLED(CONFIG_XEN_512GB); 76 77 static void __init xen_parse_512gb(void) 78 { 79 bool val = false; 80 char *arg; 81 82 arg = strstr(xen_start_info->cmd_line, "xen_512gb_limit"); 83 if (!arg) 84 return; 85 86 arg = strstr(xen_start_info->cmd_line, "xen_512gb_limit="); 87 if (!arg) 88 val = true; 89 else if (kstrtobool(arg + strlen("xen_512gb_limit="), &val)) 90 return; 91 92 xen_512gb_limit = val; 93 } 94 95 static void __init xen_add_extra_mem(unsigned long start_pfn, 96 unsigned long n_pfns) 97 { 98 int i; 99 100 /* 101 * No need to check for zero size, should happen rarely and will only 102 * write a new entry regarded to be unused due to zero size. 103 */ 104 for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) { 105 /* Add new region. */ 106 if (xen_extra_mem[i].n_pfns == 0) { 107 xen_extra_mem[i].start_pfn = start_pfn; 108 xen_extra_mem[i].n_pfns = n_pfns; 109 break; 110 } 111 /* Append to existing region. */ 112 if (xen_extra_mem[i].start_pfn + xen_extra_mem[i].n_pfns == 113 start_pfn) { 114 xen_extra_mem[i].n_pfns += n_pfns; 115 break; 116 } 117 } 118 if (i == XEN_EXTRA_MEM_MAX_REGIONS) 119 printk(KERN_WARNING "Warning: not enough extra memory regions\n"); 120 121 memblock_reserve(PFN_PHYS(start_pfn), PFN_PHYS(n_pfns)); 122 } 123 124 static void __init xen_del_extra_mem(unsigned long start_pfn, 125 unsigned long n_pfns) 126 { 127 int i; 128 unsigned long start_r, size_r; 129 130 for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) { 131 start_r = xen_extra_mem[i].start_pfn; 132 size_r = xen_extra_mem[i].n_pfns; 133 134 /* Start of region. */ 135 if (start_r == start_pfn) { 136 BUG_ON(n_pfns > size_r); 137 xen_extra_mem[i].start_pfn += n_pfns; 138 xen_extra_mem[i].n_pfns -= n_pfns; 139 break; 140 } 141 /* End of region. */ 142 if (start_r + size_r == start_pfn + n_pfns) { 143 BUG_ON(n_pfns > size_r); 144 xen_extra_mem[i].n_pfns -= n_pfns; 145 break; 146 } 147 /* Mid of region. */ 148 if (start_pfn > start_r && start_pfn < start_r + size_r) { 149 BUG_ON(start_pfn + n_pfns > start_r + size_r); 150 xen_extra_mem[i].n_pfns = start_pfn - start_r; 151 /* Calling memblock_reserve() again is okay. */ 152 xen_add_extra_mem(start_pfn + n_pfns, start_r + size_r - 153 (start_pfn + n_pfns)); 154 break; 155 } 156 } 157 memblock_phys_free(PFN_PHYS(start_pfn), PFN_PHYS(n_pfns)); 158 } 159 160 /* 161 * Called during boot before the p2m list can take entries beyond the 162 * hypervisor supplied p2m list. Entries in extra mem are to be regarded as 163 * invalid. 164 */ 165 unsigned long __ref xen_chk_extra_mem(unsigned long pfn) 166 { 167 int i; 168 169 for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) { 170 if (pfn >= xen_extra_mem[i].start_pfn && 171 pfn < xen_extra_mem[i].start_pfn + xen_extra_mem[i].n_pfns) 172 return INVALID_P2M_ENTRY; 173 } 174 175 return IDENTITY_FRAME(pfn); 176 } 177 178 /* 179 * Mark all pfns of extra mem as invalid in p2m list. 180 */ 181 void __init xen_inv_extra_mem(void) 182 { 183 unsigned long pfn, pfn_s, pfn_e; 184 int i; 185 186 for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) { 187 if (!xen_extra_mem[i].n_pfns) 188 continue; 189 pfn_s = xen_extra_mem[i].start_pfn; 190 pfn_e = pfn_s + xen_extra_mem[i].n_pfns; 191 for (pfn = pfn_s; pfn < pfn_e; pfn++) 192 set_phys_to_machine(pfn, INVALID_P2M_ENTRY); 193 } 194 } 195 196 /* 197 * Finds the next RAM pfn available in the E820 map after min_pfn. 198 * This function updates min_pfn with the pfn found and returns 199 * the size of that range or zero if not found. 200 */ 201 static unsigned long __init xen_find_pfn_range(unsigned long *min_pfn) 202 { 203 const struct e820_entry *entry = xen_e820_table.entries; 204 unsigned int i; 205 unsigned long done = 0; 206 207 for (i = 0; i < xen_e820_table.nr_entries; i++, entry++) { 208 unsigned long s_pfn; 209 unsigned long e_pfn; 210 211 if (entry->type != E820_TYPE_RAM) 212 continue; 213 214 e_pfn = PFN_DOWN(entry->addr + entry->size); 215 216 /* We only care about E820 after this */ 217 if (e_pfn <= *min_pfn) 218 continue; 219 220 s_pfn = PFN_UP(entry->addr); 221 222 /* If min_pfn falls within the E820 entry, we want to start 223 * at the min_pfn PFN. 224 */ 225 if (s_pfn <= *min_pfn) { 226 done = e_pfn - *min_pfn; 227 } else { 228 done = e_pfn - s_pfn; 229 *min_pfn = s_pfn; 230 } 231 break; 232 } 233 234 return done; 235 } 236 237 static int __init xen_free_mfn(unsigned long mfn) 238 { 239 struct xen_memory_reservation reservation = { 240 .address_bits = 0, 241 .extent_order = 0, 242 .domid = DOMID_SELF 243 }; 244 245 set_xen_guest_handle(reservation.extent_start, &mfn); 246 reservation.nr_extents = 1; 247 248 return HYPERVISOR_memory_op(XENMEM_decrease_reservation, &reservation); 249 } 250 251 /* 252 * This releases a chunk of memory and then does the identity map. It's used 253 * as a fallback if the remapping fails. 254 */ 255 static void __init xen_set_identity_and_release_chunk(unsigned long start_pfn, 256 unsigned long end_pfn, unsigned long nr_pages) 257 { 258 unsigned long pfn, end; 259 int ret; 260 261 WARN_ON(start_pfn > end_pfn); 262 263 /* Release pages first. */ 264 end = min(end_pfn, nr_pages); 265 for (pfn = start_pfn; pfn < end; pfn++) { 266 unsigned long mfn = pfn_to_mfn(pfn); 267 268 /* Make sure pfn exists to start with */ 269 if (mfn == INVALID_P2M_ENTRY || mfn_to_pfn(mfn) != pfn) 270 continue; 271 272 ret = xen_free_mfn(mfn); 273 WARN(ret != 1, "Failed to release pfn %lx err=%d\n", pfn, ret); 274 275 if (ret == 1) { 276 xen_released_pages++; 277 if (!__set_phys_to_machine(pfn, INVALID_P2M_ENTRY)) 278 break; 279 } else 280 break; 281 } 282 283 set_phys_range_identity(start_pfn, end_pfn); 284 } 285 286 /* 287 * Helper function to update the p2m and m2p tables and kernel mapping. 288 */ 289 static void __init xen_update_mem_tables(unsigned long pfn, unsigned long mfn) 290 { 291 struct mmu_update update = { 292 .ptr = ((uint64_t)mfn << PAGE_SHIFT) | MMU_MACHPHYS_UPDATE, 293 .val = pfn 294 }; 295 296 /* Update p2m */ 297 if (!set_phys_to_machine(pfn, mfn)) { 298 WARN(1, "Failed to set p2m mapping for pfn=%ld mfn=%ld\n", 299 pfn, mfn); 300 BUG(); 301 } 302 303 /* Update m2p */ 304 if (HYPERVISOR_mmu_update(&update, 1, NULL, DOMID_SELF) < 0) { 305 WARN(1, "Failed to set m2p mapping for mfn=%ld pfn=%ld\n", 306 mfn, pfn); 307 BUG(); 308 } 309 310 if (HYPERVISOR_update_va_mapping((unsigned long)__va(pfn << PAGE_SHIFT), 311 mfn_pte(mfn, PAGE_KERNEL), 0)) { 312 WARN(1, "Failed to update kernel mapping for mfn=%ld pfn=%ld\n", 313 mfn, pfn); 314 BUG(); 315 } 316 } 317 318 /* 319 * This function updates the p2m and m2p tables with an identity map from 320 * start_pfn to start_pfn+size and prepares remapping the underlying RAM of the 321 * original allocation at remap_pfn. The information needed for remapping is 322 * saved in the memory itself to avoid the need for allocating buffers. The 323 * complete remap information is contained in a list of MFNs each containing 324 * up to REMAP_SIZE MFNs and the start target PFN for doing the remap. 325 * This enables us to preserve the original mfn sequence while doing the 326 * remapping at a time when the memory management is capable of allocating 327 * virtual and physical memory in arbitrary amounts, see 'xen_remap_memory' and 328 * its callers. 329 */ 330 static void __init xen_do_set_identity_and_remap_chunk( 331 unsigned long start_pfn, unsigned long size, unsigned long remap_pfn) 332 { 333 unsigned long buf = (unsigned long)&xen_remap_buf; 334 unsigned long mfn_save, mfn; 335 unsigned long ident_pfn_iter, remap_pfn_iter; 336 unsigned long ident_end_pfn = start_pfn + size; 337 unsigned long left = size; 338 unsigned int i, chunk; 339 340 WARN_ON(size == 0); 341 342 mfn_save = virt_to_mfn(buf); 343 344 for (ident_pfn_iter = start_pfn, remap_pfn_iter = remap_pfn; 345 ident_pfn_iter < ident_end_pfn; 346 ident_pfn_iter += REMAP_SIZE, remap_pfn_iter += REMAP_SIZE) { 347 chunk = (left < REMAP_SIZE) ? left : REMAP_SIZE; 348 349 /* Map first pfn to xen_remap_buf */ 350 mfn = pfn_to_mfn(ident_pfn_iter); 351 set_pte_mfn(buf, mfn, PAGE_KERNEL); 352 353 /* Save mapping information in page */ 354 xen_remap_buf.next_area_mfn = xen_remap_mfn; 355 xen_remap_buf.target_pfn = remap_pfn_iter; 356 xen_remap_buf.size = chunk; 357 for (i = 0; i < chunk; i++) 358 xen_remap_buf.mfns[i] = pfn_to_mfn(ident_pfn_iter + i); 359 360 /* Put remap buf into list. */ 361 xen_remap_mfn = mfn; 362 363 /* Set identity map */ 364 set_phys_range_identity(ident_pfn_iter, ident_pfn_iter + chunk); 365 366 left -= chunk; 367 } 368 369 /* Restore old xen_remap_buf mapping */ 370 set_pte_mfn(buf, mfn_save, PAGE_KERNEL); 371 } 372 373 /* 374 * This function takes a contiguous pfn range that needs to be identity mapped 375 * and: 376 * 377 * 1) Finds a new range of pfns to use to remap based on E820 and remap_pfn. 378 * 2) Calls the do_ function to actually do the mapping/remapping work. 379 * 380 * The goal is to not allocate additional memory but to remap the existing 381 * pages. In the case of an error the underlying memory is simply released back 382 * to Xen and not remapped. 383 */ 384 static unsigned long __init xen_set_identity_and_remap_chunk( 385 unsigned long start_pfn, unsigned long end_pfn, unsigned long nr_pages, 386 unsigned long remap_pfn) 387 { 388 unsigned long pfn; 389 unsigned long i = 0; 390 unsigned long n = end_pfn - start_pfn; 391 392 if (remap_pfn == 0) 393 remap_pfn = nr_pages; 394 395 while (i < n) { 396 unsigned long cur_pfn = start_pfn + i; 397 unsigned long left = n - i; 398 unsigned long size = left; 399 unsigned long remap_range_size; 400 401 /* Do not remap pages beyond the current allocation */ 402 if (cur_pfn >= nr_pages) { 403 /* Identity map remaining pages */ 404 set_phys_range_identity(cur_pfn, cur_pfn + size); 405 break; 406 } 407 if (cur_pfn + size > nr_pages) 408 size = nr_pages - cur_pfn; 409 410 remap_range_size = xen_find_pfn_range(&remap_pfn); 411 if (!remap_range_size) { 412 pr_warn("Unable to find available pfn range, not remapping identity pages\n"); 413 xen_set_identity_and_release_chunk(cur_pfn, 414 cur_pfn + left, nr_pages); 415 break; 416 } 417 /* Adjust size to fit in current e820 RAM region */ 418 if (size > remap_range_size) 419 size = remap_range_size; 420 421 xen_do_set_identity_and_remap_chunk(cur_pfn, size, remap_pfn); 422 423 /* Update variables to reflect new mappings. */ 424 i += size; 425 remap_pfn += size; 426 } 427 428 /* 429 * If the PFNs are currently mapped, their VA mappings need to be 430 * zapped. 431 */ 432 for (pfn = start_pfn; pfn <= max_pfn_mapped && pfn < end_pfn; pfn++) 433 (void)HYPERVISOR_update_va_mapping( 434 (unsigned long)__va(pfn << PAGE_SHIFT), 435 native_make_pte(0), 0); 436 437 return remap_pfn; 438 } 439 440 static unsigned long __init xen_count_remap_pages( 441 unsigned long start_pfn, unsigned long end_pfn, unsigned long nr_pages, 442 unsigned long remap_pages) 443 { 444 if (start_pfn >= nr_pages) 445 return remap_pages; 446 447 return remap_pages + min(end_pfn, nr_pages) - start_pfn; 448 } 449 450 static unsigned long __init xen_foreach_remap_area(unsigned long nr_pages, 451 unsigned long (*func)(unsigned long start_pfn, unsigned long end_pfn, 452 unsigned long nr_pages, unsigned long last_val)) 453 { 454 phys_addr_t start = 0; 455 unsigned long ret_val = 0; 456 const struct e820_entry *entry = xen_e820_table.entries; 457 int i; 458 459 /* 460 * Combine non-RAM regions and gaps until a RAM region (or the 461 * end of the map) is reached, then call the provided function 462 * to perform its duty on the non-RAM region. 463 * 464 * The combined non-RAM regions are rounded to a whole number 465 * of pages so any partial pages are accessible via the 1:1 466 * mapping. This is needed for some BIOSes that put (for 467 * example) the DMI tables in a reserved region that begins on 468 * a non-page boundary. 469 */ 470 for (i = 0; i < xen_e820_table.nr_entries; i++, entry++) { 471 phys_addr_t end = entry->addr + entry->size; 472 if (entry->type == E820_TYPE_RAM || i == xen_e820_table.nr_entries - 1) { 473 unsigned long start_pfn = PFN_DOWN(start); 474 unsigned long end_pfn = PFN_UP(end); 475 476 if (entry->type == E820_TYPE_RAM) 477 end_pfn = PFN_UP(entry->addr); 478 479 if (start_pfn < end_pfn) 480 ret_val = func(start_pfn, end_pfn, nr_pages, 481 ret_val); 482 start = end; 483 } 484 } 485 486 return ret_val; 487 } 488 489 /* 490 * Remap the memory prepared in xen_do_set_identity_and_remap_chunk(). 491 * The remap information (which mfn remap to which pfn) is contained in the 492 * to be remapped memory itself in a linked list anchored at xen_remap_mfn. 493 * This scheme allows to remap the different chunks in arbitrary order while 494 * the resulting mapping will be independent from the order. 495 */ 496 void __init xen_remap_memory(void) 497 { 498 unsigned long buf = (unsigned long)&xen_remap_buf; 499 unsigned long mfn_save, pfn; 500 unsigned long remapped = 0; 501 unsigned int i; 502 unsigned long pfn_s = ~0UL; 503 unsigned long len = 0; 504 505 mfn_save = virt_to_mfn(buf); 506 507 while (xen_remap_mfn != INVALID_P2M_ENTRY) { 508 /* Map the remap information */ 509 set_pte_mfn(buf, xen_remap_mfn, PAGE_KERNEL); 510 511 BUG_ON(xen_remap_mfn != xen_remap_buf.mfns[0]); 512 513 pfn = xen_remap_buf.target_pfn; 514 for (i = 0; i < xen_remap_buf.size; i++) { 515 xen_update_mem_tables(pfn, xen_remap_buf.mfns[i]); 516 remapped++; 517 pfn++; 518 } 519 if (pfn_s == ~0UL || pfn == pfn_s) { 520 pfn_s = xen_remap_buf.target_pfn; 521 len += xen_remap_buf.size; 522 } else if (pfn_s + len == xen_remap_buf.target_pfn) { 523 len += xen_remap_buf.size; 524 } else { 525 xen_del_extra_mem(pfn_s, len); 526 pfn_s = xen_remap_buf.target_pfn; 527 len = xen_remap_buf.size; 528 } 529 xen_remap_mfn = xen_remap_buf.next_area_mfn; 530 } 531 532 if (pfn_s != ~0UL && len) 533 xen_del_extra_mem(pfn_s, len); 534 535 set_pte_mfn(buf, mfn_save, PAGE_KERNEL); 536 537 pr_info("Remapped %ld page(s)\n", remapped); 538 } 539 540 static unsigned long __init xen_get_pages_limit(void) 541 { 542 unsigned long limit; 543 544 limit = MAXMEM / PAGE_SIZE; 545 if (!xen_initial_domain() && xen_512gb_limit) 546 limit = GB(512) / PAGE_SIZE; 547 548 return limit; 549 } 550 551 static unsigned long __init xen_get_max_pages(void) 552 { 553 unsigned long max_pages, limit; 554 domid_t domid = DOMID_SELF; 555 long ret; 556 557 limit = xen_get_pages_limit(); 558 max_pages = limit; 559 560 /* 561 * For the initial domain we use the maximum reservation as 562 * the maximum page. 563 * 564 * For guest domains the current maximum reservation reflects 565 * the current maximum rather than the static maximum. In this 566 * case the e820 map provided to us will cover the static 567 * maximum region. 568 */ 569 if (xen_initial_domain()) { 570 ret = HYPERVISOR_memory_op(XENMEM_maximum_reservation, &domid); 571 if (ret > 0) 572 max_pages = ret; 573 } 574 575 return min(max_pages, limit); 576 } 577 578 static void __init xen_align_and_add_e820_region(phys_addr_t start, 579 phys_addr_t size, int type) 580 { 581 phys_addr_t end = start + size; 582 583 /* Align RAM regions to page boundaries. */ 584 if (type == E820_TYPE_RAM) { 585 start = PAGE_ALIGN(start); 586 end &= ~((phys_addr_t)PAGE_SIZE - 1); 587 #ifdef CONFIG_MEMORY_HOTPLUG 588 /* 589 * Don't allow adding memory not in E820 map while booting the 590 * system. Once the balloon driver is up it will remove that 591 * restriction again. 592 */ 593 max_mem_size = end; 594 #endif 595 } 596 597 e820__range_add(start, end - start, type); 598 } 599 600 static void __init xen_ignore_unusable(void) 601 { 602 struct e820_entry *entry = xen_e820_table.entries; 603 unsigned int i; 604 605 for (i = 0; i < xen_e820_table.nr_entries; i++, entry++) { 606 if (entry->type == E820_TYPE_UNUSABLE) 607 entry->type = E820_TYPE_RAM; 608 } 609 } 610 611 bool __init xen_is_e820_reserved(phys_addr_t start, phys_addr_t size) 612 { 613 struct e820_entry *entry; 614 unsigned mapcnt; 615 phys_addr_t end; 616 617 if (!size) 618 return false; 619 620 end = start + size; 621 entry = xen_e820_table.entries; 622 623 for (mapcnt = 0; mapcnt < xen_e820_table.nr_entries; mapcnt++) { 624 if (entry->type == E820_TYPE_RAM && entry->addr <= start && 625 (entry->addr + entry->size) >= end) 626 return false; 627 628 entry++; 629 } 630 631 return true; 632 } 633 634 /* 635 * Find a free area in physical memory not yet reserved and compliant with 636 * E820 map. 637 * Used to relocate pre-allocated areas like initrd or p2m list which are in 638 * conflict with the to be used E820 map. 639 * In case no area is found, return 0. Otherwise return the physical address 640 * of the area which is already reserved for convenience. 641 */ 642 phys_addr_t __init xen_find_free_area(phys_addr_t size) 643 { 644 unsigned mapcnt; 645 phys_addr_t addr, start; 646 struct e820_entry *entry = xen_e820_table.entries; 647 648 for (mapcnt = 0; mapcnt < xen_e820_table.nr_entries; mapcnt++, entry++) { 649 if (entry->type != E820_TYPE_RAM || entry->size < size) 650 continue; 651 start = entry->addr; 652 for (addr = start; addr < start + size; addr += PAGE_SIZE) { 653 if (!memblock_is_reserved(addr)) 654 continue; 655 start = addr + PAGE_SIZE; 656 if (start + size > entry->addr + entry->size) 657 break; 658 } 659 if (addr >= start + size) { 660 memblock_reserve(start, size); 661 return start; 662 } 663 } 664 665 return 0; 666 } 667 668 /* 669 * Like memcpy, but with physical addresses for dest and src. 670 */ 671 static void __init xen_phys_memcpy(phys_addr_t dest, phys_addr_t src, 672 phys_addr_t n) 673 { 674 phys_addr_t dest_off, src_off, dest_len, src_len, len; 675 void *from, *to; 676 677 while (n) { 678 dest_off = dest & ~PAGE_MASK; 679 src_off = src & ~PAGE_MASK; 680 dest_len = n; 681 if (dest_len > (NR_FIX_BTMAPS << PAGE_SHIFT) - dest_off) 682 dest_len = (NR_FIX_BTMAPS << PAGE_SHIFT) - dest_off; 683 src_len = n; 684 if (src_len > (NR_FIX_BTMAPS << PAGE_SHIFT) - src_off) 685 src_len = (NR_FIX_BTMAPS << PAGE_SHIFT) - src_off; 686 len = min(dest_len, src_len); 687 to = early_memremap(dest - dest_off, dest_len + dest_off); 688 from = early_memremap(src - src_off, src_len + src_off); 689 memcpy(to, from, len); 690 early_memunmap(to, dest_len + dest_off); 691 early_memunmap(from, src_len + src_off); 692 n -= len; 693 dest += len; 694 src += len; 695 } 696 } 697 698 /* 699 * Reserve Xen mfn_list. 700 */ 701 static void __init xen_reserve_xen_mfnlist(void) 702 { 703 phys_addr_t start, size; 704 705 if (xen_start_info->mfn_list >= __START_KERNEL_map) { 706 start = __pa(xen_start_info->mfn_list); 707 size = PFN_ALIGN(xen_start_info->nr_pages * 708 sizeof(unsigned long)); 709 } else { 710 start = PFN_PHYS(xen_start_info->first_p2m_pfn); 711 size = PFN_PHYS(xen_start_info->nr_p2m_frames); 712 } 713 714 memblock_reserve(start, size); 715 if (!xen_is_e820_reserved(start, size)) 716 return; 717 718 xen_relocate_p2m(); 719 memblock_phys_free(start, size); 720 } 721 722 /** 723 * xen_memory_setup - Hook for machine specific memory setup. 724 **/ 725 char * __init xen_memory_setup(void) 726 { 727 unsigned long max_pfn, pfn_s, n_pfns; 728 phys_addr_t mem_end, addr, size, chunk_size; 729 u32 type; 730 int rc; 731 struct xen_memory_map memmap; 732 unsigned long max_pages; 733 unsigned long extra_pages = 0; 734 int i; 735 int op; 736 737 xen_parse_512gb(); 738 max_pfn = xen_get_pages_limit(); 739 max_pfn = min(max_pfn, xen_start_info->nr_pages); 740 mem_end = PFN_PHYS(max_pfn); 741 742 memmap.nr_entries = ARRAY_SIZE(xen_e820_table.entries); 743 set_xen_guest_handle(memmap.buffer, xen_e820_table.entries); 744 745 #if defined(CONFIG_MEMORY_HOTPLUG) && defined(CONFIG_XEN_BALLOON) 746 xen_saved_max_mem_size = max_mem_size; 747 #endif 748 749 op = xen_initial_domain() ? 750 XENMEM_machine_memory_map : 751 XENMEM_memory_map; 752 rc = HYPERVISOR_memory_op(op, &memmap); 753 if (rc == -ENOSYS) { 754 BUG_ON(xen_initial_domain()); 755 memmap.nr_entries = 1; 756 xen_e820_table.entries[0].addr = 0ULL; 757 xen_e820_table.entries[0].size = mem_end; 758 /* 8MB slack (to balance backend allocations). */ 759 xen_e820_table.entries[0].size += 8ULL << 20; 760 xen_e820_table.entries[0].type = E820_TYPE_RAM; 761 rc = 0; 762 } 763 BUG_ON(rc); 764 BUG_ON(memmap.nr_entries == 0); 765 xen_e820_table.nr_entries = memmap.nr_entries; 766 767 /* 768 * Xen won't allow a 1:1 mapping to be created to UNUSABLE 769 * regions, so if we're using the machine memory map leave the 770 * region as RAM as it is in the pseudo-physical map. 771 * 772 * UNUSABLE regions in domUs are not handled and will need 773 * a patch in the future. 774 */ 775 if (xen_initial_domain()) 776 xen_ignore_unusable(); 777 778 /* Make sure the Xen-supplied memory map is well-ordered. */ 779 e820__update_table(&xen_e820_table); 780 781 max_pages = xen_get_max_pages(); 782 783 /* How many extra pages do we need due to remapping? */ 784 max_pages += xen_foreach_remap_area(max_pfn, xen_count_remap_pages); 785 786 if (max_pages > max_pfn) 787 extra_pages += max_pages - max_pfn; 788 789 /* 790 * Clamp the amount of extra memory to a EXTRA_MEM_RATIO 791 * factor the base size. 792 * 793 * Make sure we have no memory above max_pages, as this area 794 * isn't handled by the p2m management. 795 */ 796 extra_pages = min3(EXTRA_MEM_RATIO * min(max_pfn, PFN_DOWN(MAXMEM)), 797 extra_pages, max_pages - max_pfn); 798 i = 0; 799 addr = xen_e820_table.entries[0].addr; 800 size = xen_e820_table.entries[0].size; 801 while (i < xen_e820_table.nr_entries) { 802 bool discard = false; 803 804 chunk_size = size; 805 type = xen_e820_table.entries[i].type; 806 807 if (type == E820_TYPE_RAM) { 808 if (addr < mem_end) { 809 chunk_size = min(size, mem_end - addr); 810 } else if (extra_pages) { 811 chunk_size = min(size, PFN_PHYS(extra_pages)); 812 pfn_s = PFN_UP(addr); 813 n_pfns = PFN_DOWN(addr + chunk_size) - pfn_s; 814 extra_pages -= n_pfns; 815 xen_add_extra_mem(pfn_s, n_pfns); 816 xen_max_p2m_pfn = pfn_s + n_pfns; 817 } else 818 discard = true; 819 } 820 821 if (!discard) 822 xen_align_and_add_e820_region(addr, chunk_size, type); 823 824 addr += chunk_size; 825 size -= chunk_size; 826 if (size == 0) { 827 i++; 828 if (i < xen_e820_table.nr_entries) { 829 addr = xen_e820_table.entries[i].addr; 830 size = xen_e820_table.entries[i].size; 831 } 832 } 833 } 834 835 /* 836 * Set the rest as identity mapped, in case PCI BARs are 837 * located here. 838 */ 839 set_phys_range_identity(addr / PAGE_SIZE, ~0ul); 840 841 /* 842 * In domU, the ISA region is normal, usable memory, but we 843 * reserve ISA memory anyway because too many things poke 844 * about in there. 845 */ 846 e820__range_add(ISA_START_ADDRESS, ISA_END_ADDRESS - ISA_START_ADDRESS, E820_TYPE_RESERVED); 847 848 e820__update_table(e820_table); 849 850 /* 851 * Check whether the kernel itself conflicts with the target E820 map. 852 * Failing now is better than running into weird problems later due 853 * to relocating (and even reusing) pages with kernel text or data. 854 */ 855 if (xen_is_e820_reserved(__pa_symbol(_text), 856 __pa_symbol(__bss_stop) - __pa_symbol(_text))) { 857 xen_raw_console_write("Xen hypervisor allocated kernel memory conflicts with E820 map\n"); 858 BUG(); 859 } 860 861 /* 862 * Check for a conflict of the hypervisor supplied page tables with 863 * the target E820 map. 864 */ 865 xen_pt_check_e820(); 866 867 xen_reserve_xen_mfnlist(); 868 869 /* Check for a conflict of the initrd with the target E820 map. */ 870 if (xen_is_e820_reserved(boot_params.hdr.ramdisk_image, 871 boot_params.hdr.ramdisk_size)) { 872 phys_addr_t new_area, start, size; 873 874 new_area = xen_find_free_area(boot_params.hdr.ramdisk_size); 875 if (!new_area) { 876 xen_raw_console_write("Can't find new memory area for initrd needed due to E820 map conflict\n"); 877 BUG(); 878 } 879 880 start = boot_params.hdr.ramdisk_image; 881 size = boot_params.hdr.ramdisk_size; 882 xen_phys_memcpy(new_area, start, size); 883 pr_info("initrd moved from [mem %#010llx-%#010llx] to [mem %#010llx-%#010llx]\n", 884 start, start + size, new_area, new_area + size); 885 memblock_phys_free(start, size); 886 boot_params.hdr.ramdisk_image = new_area; 887 boot_params.ext_ramdisk_image = new_area >> 32; 888 } 889 890 /* 891 * Set identity map on non-RAM pages and prepare remapping the 892 * underlying RAM. 893 */ 894 xen_foreach_remap_area(max_pfn, xen_set_identity_and_remap_chunk); 895 896 pr_info("Released %ld page(s)\n", xen_released_pages); 897 898 return "Xen"; 899 } 900 901 static int register_callback(unsigned type, const void *func) 902 { 903 struct callback_register callback = { 904 .type = type, 905 .address = XEN_CALLBACK(__KERNEL_CS, func), 906 .flags = CALLBACKF_mask_events, 907 }; 908 909 return HYPERVISOR_callback_op(CALLBACKOP_register, &callback); 910 } 911 912 void xen_enable_sysenter(void) 913 { 914 if (cpu_feature_enabled(X86_FEATURE_SYSENTER32) && 915 register_callback(CALLBACKTYPE_sysenter, xen_entry_SYSENTER_compat)) 916 setup_clear_cpu_cap(X86_FEATURE_SYSENTER32); 917 } 918 919 void xen_enable_syscall(void) 920 { 921 int ret; 922 923 ret = register_callback(CALLBACKTYPE_syscall, xen_entry_SYSCALL_64); 924 if (ret != 0) { 925 printk(KERN_ERR "Failed to set syscall callback: %d\n", ret); 926 /* Pretty fatal; 64-bit userspace has no other 927 mechanism for syscalls. */ 928 } 929 930 if (cpu_feature_enabled(X86_FEATURE_SYSCALL32) && 931 register_callback(CALLBACKTYPE_syscall32, xen_entry_SYSCALL_compat)) 932 setup_clear_cpu_cap(X86_FEATURE_SYSCALL32); 933 } 934 935 static void __init xen_pvmmu_arch_setup(void) 936 { 937 HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_4gb_segments); 938 HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_writable_pagetables); 939 940 HYPERVISOR_vm_assist(VMASST_CMD_enable, 941 VMASST_TYPE_pae_extended_cr3); 942 943 if (register_callback(CALLBACKTYPE_event, 944 xen_asm_exc_xen_hypervisor_callback) || 945 register_callback(CALLBACKTYPE_failsafe, xen_failsafe_callback)) 946 BUG(); 947 948 xen_enable_sysenter(); 949 xen_enable_syscall(); 950 } 951 952 /* This function is not called for HVM domains */ 953 void __init xen_arch_setup(void) 954 { 955 xen_panic_handler_init(); 956 xen_pvmmu_arch_setup(); 957 958 #ifdef CONFIG_ACPI 959 if (!(xen_start_info->flags & SIF_INITDOMAIN)) { 960 printk(KERN_INFO "ACPI in unprivileged domain disabled\n"); 961 disable_acpi(); 962 } 963 #endif 964 965 memcpy(boot_command_line, xen_start_info->cmd_line, 966 MAX_GUEST_CMDLINE > COMMAND_LINE_SIZE ? 967 COMMAND_LINE_SIZE : MAX_GUEST_CMDLINE); 968 969 /* Set up idle, making sure it calls safe_halt() pvop */ 970 disable_cpuidle(); 971 disable_cpufreq(); 972 WARN_ON(xen_set_default_idle()); 973 #ifdef CONFIG_NUMA 974 numa_off = 1; 975 #endif 976 } 977