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/iscsi_ibft.h> 10 #include <linux/sched.h> 11 #include <linux/kstrtox.h> 12 #include <linux/mm.h> 13 #include <linux/pm.h> 14 #include <linux/memblock.h> 15 #include <linux/cpuidle.h> 16 #include <linux/cpufreq.h> 17 #include <linux/memory_hotplug.h> 18 19 #include <asm/elf.h> 20 #include <asm/vdso.h> 21 #include <asm/e820/api.h> 22 #include <asm/setup.h> 23 #include <asm/acpi.h> 24 #include <asm/numa.h> 25 #include <asm/idtentry.h> 26 #include <asm/xen/hypervisor.h> 27 #include <asm/xen/hypercall.h> 28 29 #include <xen/xen.h> 30 #include <xen/page.h> 31 #include <xen/interface/callback.h> 32 #include <xen/interface/memory.h> 33 #include <xen/interface/physdev.h> 34 #include <xen/features.h> 35 #include <xen/hvc-console.h> 36 #include "xen-ops.h" 37 38 #define GB(x) ((uint64_t)(x) * 1024 * 1024 * 1024) 39 40 /* Number of pages released from the initial allocation. */ 41 unsigned long xen_released_pages; 42 43 /* Memory map would allow PCI passthrough. */ 44 bool xen_pv_pci_possible; 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 static bool xen_512gb_limit __initdata = IS_ENABLED(CONFIG_XEN_512GB); 64 65 static void __init xen_parse_512gb(void) 66 { 67 bool val = false; 68 char *arg; 69 70 arg = strstr(xen_start_info->cmd_line, "xen_512gb_limit"); 71 if (!arg) 72 return; 73 74 arg = strstr(xen_start_info->cmd_line, "xen_512gb_limit="); 75 if (!arg) 76 val = true; 77 else if (kstrtobool(arg + strlen("xen_512gb_limit="), &val)) 78 return; 79 80 xen_512gb_limit = val; 81 } 82 83 static void __init xen_del_extra_mem(unsigned long start_pfn, 84 unsigned long n_pfns) 85 { 86 int i; 87 unsigned long start_r, size_r; 88 89 for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) { 90 start_r = xen_extra_mem[i].start_pfn; 91 size_r = xen_extra_mem[i].n_pfns; 92 93 /* Start of region. */ 94 if (start_r == start_pfn) { 95 BUG_ON(n_pfns > size_r); 96 xen_extra_mem[i].start_pfn += n_pfns; 97 xen_extra_mem[i].n_pfns -= n_pfns; 98 break; 99 } 100 /* End of region. */ 101 if (start_r + size_r == start_pfn + n_pfns) { 102 BUG_ON(n_pfns > size_r); 103 xen_extra_mem[i].n_pfns -= n_pfns; 104 break; 105 } 106 /* Mid of region. */ 107 if (start_pfn > start_r && start_pfn < start_r + size_r) { 108 BUG_ON(start_pfn + n_pfns > start_r + size_r); 109 xen_extra_mem[i].n_pfns = start_pfn - start_r; 110 /* Calling memblock_reserve() again is okay. */ 111 xen_add_extra_mem(start_pfn + n_pfns, start_r + size_r - 112 (start_pfn + n_pfns)); 113 break; 114 } 115 } 116 memblock_phys_free(PFN_PHYS(start_pfn), PFN_PHYS(n_pfns)); 117 } 118 119 /* 120 * Called during boot before the p2m list can take entries beyond the 121 * hypervisor supplied p2m list. Entries in extra mem are to be regarded as 122 * invalid. 123 */ 124 unsigned long __ref xen_chk_extra_mem(unsigned long pfn) 125 { 126 int i; 127 128 for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) { 129 if (pfn >= xen_extra_mem[i].start_pfn && 130 pfn < xen_extra_mem[i].start_pfn + xen_extra_mem[i].n_pfns) 131 return INVALID_P2M_ENTRY; 132 } 133 134 return IDENTITY_FRAME(pfn); 135 } 136 137 /* 138 * Mark all pfns of extra mem as invalid in p2m list. 139 */ 140 void __init xen_inv_extra_mem(void) 141 { 142 unsigned long pfn, pfn_s, pfn_e; 143 int i; 144 145 for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) { 146 if (!xen_extra_mem[i].n_pfns) 147 continue; 148 pfn_s = xen_extra_mem[i].start_pfn; 149 pfn_e = pfn_s + xen_extra_mem[i].n_pfns; 150 for (pfn = pfn_s; pfn < pfn_e; pfn++) 151 set_phys_to_machine(pfn, INVALID_P2M_ENTRY); 152 } 153 } 154 155 /* 156 * Finds the next RAM pfn available in the E820 map after min_pfn. 157 * This function updates min_pfn with the pfn found and returns 158 * the size of that range or zero if not found. 159 */ 160 static unsigned long __init xen_find_pfn_range(unsigned long *min_pfn) 161 { 162 const struct e820_entry *entry = xen_e820_table.entries; 163 unsigned int i; 164 unsigned long done = 0; 165 166 for (i = 0; i < xen_e820_table.nr_entries; i++, entry++) { 167 unsigned long s_pfn; 168 unsigned long e_pfn; 169 170 if (entry->type != E820_TYPE_RAM) 171 continue; 172 173 e_pfn = PFN_DOWN(entry->addr + entry->size); 174 175 /* We only care about E820 after this */ 176 if (e_pfn <= *min_pfn) 177 continue; 178 179 s_pfn = PFN_UP(entry->addr); 180 181 /* If min_pfn falls within the E820 entry, we want to start 182 * at the min_pfn PFN. 183 */ 184 if (s_pfn <= *min_pfn) { 185 done = e_pfn - *min_pfn; 186 } else { 187 done = e_pfn - s_pfn; 188 *min_pfn = s_pfn; 189 } 190 break; 191 } 192 193 return done; 194 } 195 196 static int __init xen_free_mfn(unsigned long mfn) 197 { 198 struct xen_memory_reservation reservation = { 199 .address_bits = 0, 200 .extent_order = 0, 201 .domid = DOMID_SELF 202 }; 203 204 set_xen_guest_handle(reservation.extent_start, &mfn); 205 reservation.nr_extents = 1; 206 207 return HYPERVISOR_memory_op(XENMEM_decrease_reservation, &reservation); 208 } 209 210 /* 211 * This releases a chunk of memory and then does the identity map. It's used 212 * as a fallback if the remapping fails. 213 */ 214 static void __init xen_set_identity_and_release_chunk(unsigned long start_pfn, 215 unsigned long end_pfn, unsigned long nr_pages) 216 { 217 unsigned long pfn, end; 218 int ret; 219 220 WARN_ON(start_pfn > end_pfn); 221 222 /* Release pages first. */ 223 end = min(end_pfn, nr_pages); 224 for (pfn = start_pfn; pfn < end; pfn++) { 225 unsigned long mfn = pfn_to_mfn(pfn); 226 227 /* Make sure pfn exists to start with */ 228 if (mfn == INVALID_P2M_ENTRY || mfn_to_pfn(mfn) != pfn) 229 continue; 230 231 ret = xen_free_mfn(mfn); 232 WARN(ret != 1, "Failed to release pfn %lx err=%d\n", pfn, ret); 233 234 if (ret == 1) { 235 xen_released_pages++; 236 if (!__set_phys_to_machine(pfn, INVALID_P2M_ENTRY)) 237 break; 238 } else 239 break; 240 } 241 242 set_phys_range_identity(start_pfn, end_pfn); 243 } 244 245 /* 246 * Helper function to update the p2m and m2p tables and kernel mapping. 247 */ 248 static void __init xen_update_mem_tables(unsigned long pfn, unsigned long mfn) 249 { 250 struct mmu_update update = { 251 .ptr = ((uint64_t)mfn << PAGE_SHIFT) | MMU_MACHPHYS_UPDATE, 252 .val = pfn 253 }; 254 255 /* Update p2m */ 256 if (!set_phys_to_machine(pfn, mfn)) { 257 WARN(1, "Failed to set p2m mapping for pfn=%ld mfn=%ld\n", 258 pfn, mfn); 259 BUG(); 260 } 261 262 /* Update m2p */ 263 if (HYPERVISOR_mmu_update(&update, 1, NULL, DOMID_SELF) < 0) { 264 WARN(1, "Failed to set m2p mapping for mfn=%ld pfn=%ld\n", 265 mfn, pfn); 266 BUG(); 267 } 268 269 if (HYPERVISOR_update_va_mapping((unsigned long)__va(pfn << PAGE_SHIFT), 270 mfn_pte(mfn, PAGE_KERNEL), 0)) { 271 WARN(1, "Failed to update kernel mapping for mfn=%ld pfn=%ld\n", 272 mfn, pfn); 273 BUG(); 274 } 275 } 276 277 /* 278 * This function updates the p2m and m2p tables with an identity map from 279 * start_pfn to start_pfn+size and prepares remapping the underlying RAM of the 280 * original allocation at remap_pfn. The information needed for remapping is 281 * saved in the memory itself to avoid the need for allocating buffers. The 282 * complete remap information is contained in a list of MFNs each containing 283 * up to REMAP_SIZE MFNs and the start target PFN for doing the remap. 284 * This enables us to preserve the original mfn sequence while doing the 285 * remapping at a time when the memory management is capable of allocating 286 * virtual and physical memory in arbitrary amounts, see 'xen_remap_memory' and 287 * its callers. 288 */ 289 static void __init xen_do_set_identity_and_remap_chunk( 290 unsigned long start_pfn, unsigned long size, unsigned long remap_pfn) 291 { 292 unsigned long buf = (unsigned long)&xen_remap_buf; 293 unsigned long mfn_save, mfn; 294 unsigned long ident_pfn_iter, remap_pfn_iter; 295 unsigned long ident_end_pfn = start_pfn + size; 296 unsigned long left = size; 297 unsigned int i, chunk; 298 299 WARN_ON(size == 0); 300 301 mfn_save = virt_to_mfn((void *)buf); 302 303 for (ident_pfn_iter = start_pfn, remap_pfn_iter = remap_pfn; 304 ident_pfn_iter < ident_end_pfn; 305 ident_pfn_iter += REMAP_SIZE, remap_pfn_iter += REMAP_SIZE) { 306 chunk = (left < REMAP_SIZE) ? left : REMAP_SIZE; 307 308 /* Map first pfn to xen_remap_buf */ 309 mfn = pfn_to_mfn(ident_pfn_iter); 310 set_pte_mfn(buf, mfn, PAGE_KERNEL); 311 312 /* Save mapping information in page */ 313 xen_remap_buf.next_area_mfn = xen_remap_mfn; 314 xen_remap_buf.target_pfn = remap_pfn_iter; 315 xen_remap_buf.size = chunk; 316 for (i = 0; i < chunk; i++) 317 xen_remap_buf.mfns[i] = pfn_to_mfn(ident_pfn_iter + i); 318 319 /* Put remap buf into list. */ 320 xen_remap_mfn = mfn; 321 322 /* Set identity map */ 323 set_phys_range_identity(ident_pfn_iter, ident_pfn_iter + chunk); 324 325 left -= chunk; 326 } 327 328 /* Restore old xen_remap_buf mapping */ 329 set_pte_mfn(buf, mfn_save, PAGE_KERNEL); 330 } 331 332 /* 333 * This function takes a contiguous pfn range that needs to be identity mapped 334 * and: 335 * 336 * 1) Finds a new range of pfns to use to remap based on E820 and remap_pfn. 337 * 2) Calls the do_ function to actually do the mapping/remapping work. 338 * 339 * The goal is to not allocate additional memory but to remap the existing 340 * pages. In the case of an error the underlying memory is simply released back 341 * to Xen and not remapped. 342 */ 343 static unsigned long __init xen_set_identity_and_remap_chunk( 344 unsigned long start_pfn, unsigned long end_pfn, unsigned long nr_pages, 345 unsigned long remap_pfn) 346 { 347 unsigned long pfn; 348 unsigned long i = 0; 349 unsigned long n = end_pfn - start_pfn; 350 351 if (remap_pfn == 0) 352 remap_pfn = nr_pages; 353 354 while (i < n) { 355 unsigned long cur_pfn = start_pfn + i; 356 unsigned long left = n - i; 357 unsigned long size = left; 358 unsigned long remap_range_size; 359 360 /* Do not remap pages beyond the current allocation */ 361 if (cur_pfn >= nr_pages) { 362 /* Identity map remaining pages */ 363 set_phys_range_identity(cur_pfn, cur_pfn + size); 364 break; 365 } 366 if (cur_pfn + size > nr_pages) 367 size = nr_pages - cur_pfn; 368 369 remap_range_size = xen_find_pfn_range(&remap_pfn); 370 if (!remap_range_size) { 371 pr_warn("Unable to find available pfn range, not remapping identity pages\n"); 372 xen_set_identity_and_release_chunk(cur_pfn, 373 cur_pfn + left, nr_pages); 374 break; 375 } 376 /* Adjust size to fit in current e820 RAM region */ 377 if (size > remap_range_size) 378 size = remap_range_size; 379 380 xen_do_set_identity_and_remap_chunk(cur_pfn, size, remap_pfn); 381 382 /* Update variables to reflect new mappings. */ 383 i += size; 384 remap_pfn += size; 385 } 386 387 /* 388 * If the PFNs are currently mapped, their VA mappings need to be 389 * zapped. 390 */ 391 for (pfn = start_pfn; pfn <= max_pfn_mapped && pfn < end_pfn; pfn++) 392 (void)HYPERVISOR_update_va_mapping( 393 (unsigned long)__va(pfn << PAGE_SHIFT), 394 native_make_pte(0), 0); 395 396 return remap_pfn; 397 } 398 399 static unsigned long __init xen_count_remap_pages( 400 unsigned long start_pfn, unsigned long end_pfn, unsigned long nr_pages, 401 unsigned long remap_pages) 402 { 403 if (start_pfn >= nr_pages) 404 return remap_pages; 405 406 return remap_pages + min(end_pfn, nr_pages) - start_pfn; 407 } 408 409 static unsigned long __init xen_foreach_remap_area(unsigned long nr_pages, 410 unsigned long (*func)(unsigned long start_pfn, unsigned long end_pfn, 411 unsigned long nr_pages, unsigned long last_val)) 412 { 413 phys_addr_t start = 0; 414 unsigned long ret_val = 0; 415 const struct e820_entry *entry = xen_e820_table.entries; 416 int i; 417 418 /* 419 * Combine non-RAM regions and gaps until a RAM region (or the 420 * end of the map) is reached, then call the provided function 421 * to perform its duty on the non-RAM region. 422 * 423 * The combined non-RAM regions are rounded to a whole number 424 * of pages so any partial pages are accessible via the 1:1 425 * mapping. This is needed for some BIOSes that put (for 426 * example) the DMI tables in a reserved region that begins on 427 * a non-page boundary. 428 */ 429 for (i = 0; i < xen_e820_table.nr_entries; i++, entry++) { 430 phys_addr_t end = entry->addr + entry->size; 431 if (entry->type == E820_TYPE_RAM || i == xen_e820_table.nr_entries - 1) { 432 unsigned long start_pfn = PFN_DOWN(start); 433 unsigned long end_pfn = PFN_UP(end); 434 435 if (entry->type == E820_TYPE_RAM) 436 end_pfn = PFN_UP(entry->addr); 437 438 if (start_pfn < end_pfn) 439 ret_val = func(start_pfn, end_pfn, nr_pages, 440 ret_val); 441 start = end; 442 } 443 } 444 445 return ret_val; 446 } 447 448 /* 449 * Remap the memory prepared in xen_do_set_identity_and_remap_chunk(). 450 * The remap information (which mfn remap to which pfn) is contained in the 451 * to be remapped memory itself in a linked list anchored at xen_remap_mfn. 452 * This scheme allows to remap the different chunks in arbitrary order while 453 * the resulting mapping will be independent from the order. 454 */ 455 void __init xen_remap_memory(void) 456 { 457 unsigned long buf = (unsigned long)&xen_remap_buf; 458 unsigned long mfn_save, pfn; 459 unsigned long remapped = 0; 460 unsigned int i; 461 unsigned long pfn_s = ~0UL; 462 unsigned long len = 0; 463 464 mfn_save = virt_to_mfn((void *)buf); 465 466 while (xen_remap_mfn != INVALID_P2M_ENTRY) { 467 /* Map the remap information */ 468 set_pte_mfn(buf, xen_remap_mfn, PAGE_KERNEL); 469 470 BUG_ON(xen_remap_mfn != xen_remap_buf.mfns[0]); 471 472 pfn = xen_remap_buf.target_pfn; 473 for (i = 0; i < xen_remap_buf.size; i++) { 474 xen_update_mem_tables(pfn, xen_remap_buf.mfns[i]); 475 remapped++; 476 pfn++; 477 } 478 if (pfn_s == ~0UL || pfn == pfn_s) { 479 pfn_s = xen_remap_buf.target_pfn; 480 len += xen_remap_buf.size; 481 } else if (pfn_s + len == xen_remap_buf.target_pfn) { 482 len += xen_remap_buf.size; 483 } else { 484 xen_del_extra_mem(pfn_s, len); 485 pfn_s = xen_remap_buf.target_pfn; 486 len = xen_remap_buf.size; 487 } 488 xen_remap_mfn = xen_remap_buf.next_area_mfn; 489 } 490 491 if (pfn_s != ~0UL && len) 492 xen_del_extra_mem(pfn_s, len); 493 494 set_pte_mfn(buf, mfn_save, PAGE_KERNEL); 495 496 pr_info("Remapped %ld page(s)\n", remapped); 497 } 498 499 static unsigned long __init xen_get_pages_limit(void) 500 { 501 unsigned long limit; 502 503 limit = MAXMEM / PAGE_SIZE; 504 if (!xen_initial_domain() && xen_512gb_limit) 505 limit = GB(512) / PAGE_SIZE; 506 507 return limit; 508 } 509 510 static unsigned long __init xen_get_max_pages(void) 511 { 512 unsigned long max_pages, limit; 513 domid_t domid = DOMID_SELF; 514 long ret; 515 516 limit = xen_get_pages_limit(); 517 max_pages = limit; 518 519 /* 520 * For the initial domain we use the maximum reservation as 521 * the maximum page. 522 * 523 * For guest domains the current maximum reservation reflects 524 * the current maximum rather than the static maximum. In this 525 * case the e820 map provided to us will cover the static 526 * maximum region. 527 */ 528 if (xen_initial_domain()) { 529 ret = HYPERVISOR_memory_op(XENMEM_maximum_reservation, &domid); 530 if (ret > 0) 531 max_pages = ret; 532 } 533 534 return min(max_pages, limit); 535 } 536 537 static void __init xen_align_and_add_e820_region(phys_addr_t start, 538 phys_addr_t size, int type) 539 { 540 phys_addr_t end = start + size; 541 542 /* Align RAM regions to page boundaries. */ 543 if (type == E820_TYPE_RAM) { 544 start = PAGE_ALIGN(start); 545 end &= ~((phys_addr_t)PAGE_SIZE - 1); 546 #ifdef CONFIG_MEMORY_HOTPLUG 547 /* 548 * Don't allow adding memory not in E820 map while booting the 549 * system. Once the balloon driver is up it will remove that 550 * restriction again. 551 */ 552 max_mem_size = end; 553 #endif 554 } 555 556 e820__range_add(start, end - start, type); 557 } 558 559 static void __init xen_ignore_unusable(void) 560 { 561 struct e820_entry *entry = xen_e820_table.entries; 562 unsigned int i; 563 564 for (i = 0; i < xen_e820_table.nr_entries; i++, entry++) { 565 if (entry->type == E820_TYPE_UNUSABLE) 566 entry->type = E820_TYPE_RAM; 567 } 568 } 569 570 bool __init xen_is_e820_reserved(phys_addr_t start, phys_addr_t size) 571 { 572 struct e820_entry *entry; 573 unsigned mapcnt; 574 phys_addr_t end; 575 576 if (!size) 577 return false; 578 579 end = start + size; 580 entry = xen_e820_table.entries; 581 582 for (mapcnt = 0; mapcnt < xen_e820_table.nr_entries; mapcnt++) { 583 if (entry->type == E820_TYPE_RAM && entry->addr <= start && 584 (entry->addr + entry->size) >= end) 585 return false; 586 587 entry++; 588 } 589 590 return true; 591 } 592 593 /* 594 * Find a free area in physical memory not yet reserved and compliant with 595 * E820 map. 596 * Used to relocate pre-allocated areas like initrd or p2m list which are in 597 * conflict with the to be used E820 map. 598 * In case no area is found, return 0. Otherwise return the physical address 599 * of the area which is already reserved for convenience. 600 */ 601 phys_addr_t __init xen_find_free_area(phys_addr_t size) 602 { 603 unsigned mapcnt; 604 phys_addr_t addr, start; 605 struct e820_entry *entry = xen_e820_table.entries; 606 607 for (mapcnt = 0; mapcnt < xen_e820_table.nr_entries; mapcnt++, entry++) { 608 if (entry->type != E820_TYPE_RAM || entry->size < size) 609 continue; 610 start = entry->addr; 611 for (addr = start; addr < start + size; addr += PAGE_SIZE) { 612 if (!memblock_is_reserved(addr)) 613 continue; 614 start = addr + PAGE_SIZE; 615 if (start + size > entry->addr + entry->size) 616 break; 617 } 618 if (addr >= start + size) { 619 memblock_reserve(start, size); 620 return start; 621 } 622 } 623 624 return 0; 625 } 626 627 /* 628 * Like memcpy, but with physical addresses for dest and src. 629 */ 630 static void __init xen_phys_memcpy(phys_addr_t dest, phys_addr_t src, 631 phys_addr_t n) 632 { 633 phys_addr_t dest_off, src_off, dest_len, src_len, len; 634 void *from, *to; 635 636 while (n) { 637 dest_off = dest & ~PAGE_MASK; 638 src_off = src & ~PAGE_MASK; 639 dest_len = n; 640 if (dest_len > (NR_FIX_BTMAPS << PAGE_SHIFT) - dest_off) 641 dest_len = (NR_FIX_BTMAPS << PAGE_SHIFT) - dest_off; 642 src_len = n; 643 if (src_len > (NR_FIX_BTMAPS << PAGE_SHIFT) - src_off) 644 src_len = (NR_FIX_BTMAPS << PAGE_SHIFT) - src_off; 645 len = min(dest_len, src_len); 646 to = early_memremap(dest - dest_off, dest_len + dest_off); 647 from = early_memremap(src - src_off, src_len + src_off); 648 memcpy(to, from, len); 649 early_memunmap(to, dest_len + dest_off); 650 early_memunmap(from, src_len + src_off); 651 n -= len; 652 dest += len; 653 src += len; 654 } 655 } 656 657 /* 658 * Reserve Xen mfn_list. 659 */ 660 static void __init xen_reserve_xen_mfnlist(void) 661 { 662 phys_addr_t start, size; 663 664 if (xen_start_info->mfn_list >= __START_KERNEL_map) { 665 start = __pa(xen_start_info->mfn_list); 666 size = PFN_ALIGN(xen_start_info->nr_pages * 667 sizeof(unsigned long)); 668 } else { 669 start = PFN_PHYS(xen_start_info->first_p2m_pfn); 670 size = PFN_PHYS(xen_start_info->nr_p2m_frames); 671 } 672 673 memblock_reserve(start, size); 674 if (!xen_is_e820_reserved(start, size)) 675 return; 676 677 xen_relocate_p2m(); 678 memblock_phys_free(start, size); 679 } 680 681 /** 682 * xen_memory_setup - Hook for machine specific memory setup. 683 **/ 684 char * __init xen_memory_setup(void) 685 { 686 unsigned long max_pfn, pfn_s, n_pfns; 687 phys_addr_t mem_end, addr, size, chunk_size; 688 u32 type; 689 int rc; 690 struct xen_memory_map memmap; 691 unsigned long max_pages; 692 unsigned long extra_pages = 0; 693 unsigned long maxmem_pages; 694 int i; 695 int op; 696 697 xen_parse_512gb(); 698 max_pfn = xen_get_pages_limit(); 699 max_pfn = min(max_pfn, xen_start_info->nr_pages); 700 mem_end = PFN_PHYS(max_pfn); 701 702 memmap.nr_entries = ARRAY_SIZE(xen_e820_table.entries); 703 set_xen_guest_handle(memmap.buffer, xen_e820_table.entries); 704 705 #if defined(CONFIG_MEMORY_HOTPLUG) && defined(CONFIG_XEN_BALLOON) 706 xen_saved_max_mem_size = max_mem_size; 707 #endif 708 709 op = xen_initial_domain() ? 710 XENMEM_machine_memory_map : 711 XENMEM_memory_map; 712 rc = HYPERVISOR_memory_op(op, &memmap); 713 if (rc == -ENOSYS) { 714 BUG_ON(xen_initial_domain()); 715 memmap.nr_entries = 1; 716 xen_e820_table.entries[0].addr = 0ULL; 717 xen_e820_table.entries[0].size = mem_end; 718 /* 8MB slack (to balance backend allocations). */ 719 xen_e820_table.entries[0].size += 8ULL << 20; 720 xen_e820_table.entries[0].type = E820_TYPE_RAM; 721 rc = 0; 722 } 723 BUG_ON(rc); 724 BUG_ON(memmap.nr_entries == 0); 725 xen_e820_table.nr_entries = memmap.nr_entries; 726 727 if (xen_initial_domain()) { 728 /* 729 * Xen won't allow a 1:1 mapping to be created to UNUSABLE 730 * regions, so if we're using the machine memory map leave the 731 * region as RAM as it is in the pseudo-physical map. 732 * 733 * UNUSABLE regions in domUs are not handled and will need 734 * a patch in the future. 735 */ 736 xen_ignore_unusable(); 737 738 #ifdef CONFIG_ISCSI_IBFT_FIND 739 /* Reserve 0.5 MiB to 1 MiB region so iBFT can be found */ 740 xen_e820_table.entries[xen_e820_table.nr_entries].addr = IBFT_START; 741 xen_e820_table.entries[xen_e820_table.nr_entries].size = IBFT_END - IBFT_START; 742 xen_e820_table.entries[xen_e820_table.nr_entries].type = E820_TYPE_RESERVED; 743 xen_e820_table.nr_entries++; 744 #endif 745 } 746 747 /* Make sure the Xen-supplied memory map is well-ordered. */ 748 e820__update_table(&xen_e820_table); 749 750 max_pages = xen_get_max_pages(); 751 752 /* How many extra pages do we need due to remapping? */ 753 max_pages += xen_foreach_remap_area(max_pfn, xen_count_remap_pages); 754 755 if (max_pages > max_pfn) 756 extra_pages += max_pages - max_pfn; 757 758 /* 759 * Clamp the amount of extra memory to a EXTRA_MEM_RATIO 760 * factor the base size. 761 * 762 * Make sure we have no memory above max_pages, as this area 763 * isn't handled by the p2m management. 764 */ 765 maxmem_pages = EXTRA_MEM_RATIO * min(max_pfn, PFN_DOWN(MAXMEM)); 766 extra_pages = min3(maxmem_pages, extra_pages, max_pages - max_pfn); 767 i = 0; 768 addr = xen_e820_table.entries[0].addr; 769 size = xen_e820_table.entries[0].size; 770 while (i < xen_e820_table.nr_entries) { 771 bool discard = false; 772 773 chunk_size = size; 774 type = xen_e820_table.entries[i].type; 775 776 if (type == E820_TYPE_RESERVED) 777 xen_pv_pci_possible = true; 778 779 if (type == E820_TYPE_RAM) { 780 if (addr < mem_end) { 781 chunk_size = min(size, mem_end - addr); 782 } else if (extra_pages) { 783 chunk_size = min(size, PFN_PHYS(extra_pages)); 784 pfn_s = PFN_UP(addr); 785 n_pfns = PFN_DOWN(addr + chunk_size) - pfn_s; 786 extra_pages -= n_pfns; 787 xen_add_extra_mem(pfn_s, n_pfns); 788 xen_max_p2m_pfn = pfn_s + n_pfns; 789 } else 790 discard = true; 791 } 792 793 if (!discard) 794 xen_align_and_add_e820_region(addr, chunk_size, type); 795 796 addr += chunk_size; 797 size -= chunk_size; 798 if (size == 0) { 799 i++; 800 if (i < xen_e820_table.nr_entries) { 801 addr = xen_e820_table.entries[i].addr; 802 size = xen_e820_table.entries[i].size; 803 } 804 } 805 } 806 807 /* 808 * Set the rest as identity mapped, in case PCI BARs are 809 * located here. 810 */ 811 set_phys_range_identity(addr / PAGE_SIZE, ~0ul); 812 813 /* 814 * In domU, the ISA region is normal, usable memory, but we 815 * reserve ISA memory anyway because too many things poke 816 * about in there. 817 */ 818 e820__range_add(ISA_START_ADDRESS, ISA_END_ADDRESS - ISA_START_ADDRESS, E820_TYPE_RESERVED); 819 820 e820__update_table(e820_table); 821 822 /* 823 * Check whether the kernel itself conflicts with the target E820 map. 824 * Failing now is better than running into weird problems later due 825 * to relocating (and even reusing) pages with kernel text or data. 826 */ 827 if (xen_is_e820_reserved(__pa_symbol(_text), 828 __pa_symbol(__bss_stop) - __pa_symbol(_text))) { 829 xen_raw_console_write("Xen hypervisor allocated kernel memory conflicts with E820 map\n"); 830 BUG(); 831 } 832 833 /* 834 * Check for a conflict of the hypervisor supplied page tables with 835 * the target E820 map. 836 */ 837 xen_pt_check_e820(); 838 839 xen_reserve_xen_mfnlist(); 840 841 /* Check for a conflict of the initrd with the target E820 map. */ 842 if (xen_is_e820_reserved(boot_params.hdr.ramdisk_image, 843 boot_params.hdr.ramdisk_size)) { 844 phys_addr_t new_area, start, size; 845 846 new_area = xen_find_free_area(boot_params.hdr.ramdisk_size); 847 if (!new_area) { 848 xen_raw_console_write("Can't find new memory area for initrd needed due to E820 map conflict\n"); 849 BUG(); 850 } 851 852 start = boot_params.hdr.ramdisk_image; 853 size = boot_params.hdr.ramdisk_size; 854 xen_phys_memcpy(new_area, start, size); 855 pr_info("initrd moved from [mem %#010llx-%#010llx] to [mem %#010llx-%#010llx]\n", 856 start, start + size, new_area, new_area + size); 857 memblock_phys_free(start, size); 858 boot_params.hdr.ramdisk_image = new_area; 859 boot_params.ext_ramdisk_image = new_area >> 32; 860 } 861 862 /* 863 * Set identity map on non-RAM pages and prepare remapping the 864 * underlying RAM. 865 */ 866 xen_foreach_remap_area(max_pfn, xen_set_identity_and_remap_chunk); 867 868 pr_info("Released %ld page(s)\n", xen_released_pages); 869 870 return "Xen"; 871 } 872 873 static int register_callback(unsigned type, const void *func) 874 { 875 struct callback_register callback = { 876 .type = type, 877 .address = XEN_CALLBACK(__KERNEL_CS, func), 878 .flags = CALLBACKF_mask_events, 879 }; 880 881 return HYPERVISOR_callback_op(CALLBACKOP_register, &callback); 882 } 883 884 void xen_enable_sysenter(void) 885 { 886 if (cpu_feature_enabled(X86_FEATURE_SYSENTER32) && 887 register_callback(CALLBACKTYPE_sysenter, xen_entry_SYSENTER_compat)) 888 setup_clear_cpu_cap(X86_FEATURE_SYSENTER32); 889 } 890 891 void xen_enable_syscall(void) 892 { 893 int ret; 894 895 ret = register_callback(CALLBACKTYPE_syscall, xen_entry_SYSCALL_64); 896 if (ret != 0) { 897 printk(KERN_ERR "Failed to set syscall callback: %d\n", ret); 898 /* Pretty fatal; 64-bit userspace has no other 899 mechanism for syscalls. */ 900 } 901 902 if (cpu_feature_enabled(X86_FEATURE_SYSCALL32) && 903 register_callback(CALLBACKTYPE_syscall32, xen_entry_SYSCALL_compat)) 904 setup_clear_cpu_cap(X86_FEATURE_SYSCALL32); 905 } 906 907 static void __init xen_pvmmu_arch_setup(void) 908 { 909 HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_writable_pagetables); 910 911 if (register_callback(CALLBACKTYPE_event, 912 xen_asm_exc_xen_hypervisor_callback) || 913 register_callback(CALLBACKTYPE_failsafe, xen_failsafe_callback)) 914 BUG(); 915 916 xen_enable_sysenter(); 917 xen_enable_syscall(); 918 } 919 920 /* This function is not called for HVM domains */ 921 void __init xen_arch_setup(void) 922 { 923 xen_panic_handler_init(); 924 xen_pvmmu_arch_setup(); 925 926 #ifdef CONFIG_ACPI 927 if (!(xen_start_info->flags & SIF_INITDOMAIN)) { 928 printk(KERN_INFO "ACPI in unprivileged domain disabled\n"); 929 disable_acpi(); 930 } 931 #endif 932 933 memcpy(boot_command_line, xen_start_info->cmd_line, 934 MAX_GUEST_CMDLINE > COMMAND_LINE_SIZE ? 935 COMMAND_LINE_SIZE : MAX_GUEST_CMDLINE); 936 937 /* Set up idle, making sure it calls safe_halt() pvop */ 938 disable_cpuidle(); 939 disable_cpufreq(); 940 WARN_ON(xen_set_default_idle()); 941 #ifdef CONFIG_NUMA 942 numa_off = 1; 943 #endif 944 } 945