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