2 * Machine specific setup for xen
4 * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007
7 #include <linux/module.h>
8 #include <linux/sched.h>
11 #include <linux/memblock.h>
12 #include <linux/cpuidle.h>
13 #include <linux/cpufreq.h>
18 #include <asm/setup.h>
21 #include <asm/xen/hypervisor.h>
22 #include <asm/xen/hypercall.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>
36 #define GB(x) ((uint64_t)(x) * 1024 * 1024 * 1024)
38 /* Amount of extra memory space we add to the e820 ranges */
39 struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata;
41 /* Number of pages released from the initial allocation. */
42 unsigned long xen_released_pages;
44 /* E820 map used during setting up memory. */
45 static struct e820entry xen_e820_map[E820MAX] __initdata;
46 static u32 xen_e820_map_entries __initdata;
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
53 #define REMAP_SIZE (P2M_PER_PAGE - 3)
55 unsigned long next_area_mfn;
56 unsigned long target_pfn;
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;
63 * The maximum amount of extra memory compared to the base size. The
64 * main scaling factor is the size of struct page. At extreme ratios
65 * of base:extra, all the base memory can be filled with page
66 * structures for the extra memory, leaving no space for anything
69 * 10x seems like a reasonable balance between scaling flexibility and
70 * leaving a practically usable system.
72 #define EXTRA_MEM_RATIO (10)
74 static bool xen_512gb_limit __initdata = IS_ENABLED(CONFIG_XEN_512GB);
76 static void __init xen_parse_512gb(void)
81 arg = strstr(xen_start_info->cmd_line, "xen_512gb_limit");
85 arg = strstr(xen_start_info->cmd_line, "xen_512gb_limit=");
88 else if (strtobool(arg + strlen("xen_512gb_limit="), &val))
91 xen_512gb_limit = val;
94 static void __init xen_add_extra_mem(phys_addr_t start, phys_addr_t size)
98 for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) {
100 if (xen_extra_mem[i].size == 0) {
101 xen_extra_mem[i].start = start;
102 xen_extra_mem[i].size = size;
105 /* Append to existing region. */
106 if (xen_extra_mem[i].start + xen_extra_mem[i].size == start) {
107 xen_extra_mem[i].size += size;
111 if (i == XEN_EXTRA_MEM_MAX_REGIONS)
112 printk(KERN_WARNING "Warning: not enough extra memory regions\n");
114 memblock_reserve(start, size);
117 static void __init xen_del_extra_mem(phys_addr_t start, phys_addr_t size)
120 phys_addr_t start_r, size_r;
122 for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) {
123 start_r = xen_extra_mem[i].start;
124 size_r = xen_extra_mem[i].size;
126 /* Start of region. */
127 if (start_r == start) {
128 BUG_ON(size > size_r);
129 xen_extra_mem[i].start += size;
130 xen_extra_mem[i].size -= size;
134 if (start_r + size_r == start + size) {
135 BUG_ON(size > size_r);
136 xen_extra_mem[i].size -= size;
140 if (start > start_r && start < start_r + size_r) {
141 BUG_ON(start + size > start_r + size_r);
142 xen_extra_mem[i].size = start - start_r;
143 /* Calling memblock_reserve() again is okay. */
144 xen_add_extra_mem(start + size, start_r + size_r -
149 memblock_free(start, size);
153 * Called during boot before the p2m list can take entries beyond the
154 * hypervisor supplied p2m list. Entries in extra mem are to be regarded as
157 unsigned long __ref xen_chk_extra_mem(unsigned long pfn)
160 phys_addr_t addr = PFN_PHYS(pfn);
162 for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) {
163 if (addr >= xen_extra_mem[i].start &&
164 addr < xen_extra_mem[i].start + xen_extra_mem[i].size)
165 return INVALID_P2M_ENTRY;
168 return IDENTITY_FRAME(pfn);
172 * Mark all pfns of extra mem as invalid in p2m list.
174 void __init xen_inv_extra_mem(void)
176 unsigned long pfn, pfn_s, pfn_e;
179 for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) {
180 if (!xen_extra_mem[i].size)
182 pfn_s = PFN_DOWN(xen_extra_mem[i].start);
183 pfn_e = PFN_UP(xen_extra_mem[i].start + xen_extra_mem[i].size);
184 for (pfn = pfn_s; pfn < pfn_e; pfn++)
185 set_phys_to_machine(pfn, INVALID_P2M_ENTRY);
190 * Finds the next RAM pfn available in the E820 map after min_pfn.
191 * This function updates min_pfn with the pfn found and returns
192 * the size of that range or zero if not found.
194 static unsigned long __init xen_find_pfn_range(unsigned long *min_pfn)
196 const struct e820entry *entry = xen_e820_map;
198 unsigned long done = 0;
200 for (i = 0; i < xen_e820_map_entries; i++, entry++) {
204 if (entry->type != E820_RAM)
207 e_pfn = PFN_DOWN(entry->addr + entry->size);
209 /* We only care about E820 after this */
210 if (e_pfn < *min_pfn)
213 s_pfn = PFN_UP(entry->addr);
215 /* If min_pfn falls within the E820 entry, we want to start
216 * at the min_pfn PFN.
218 if (s_pfn <= *min_pfn) {
219 done = e_pfn - *min_pfn;
221 done = e_pfn - s_pfn;
230 static int __init xen_free_mfn(unsigned long mfn)
232 struct xen_memory_reservation reservation = {
238 set_xen_guest_handle(reservation.extent_start, &mfn);
239 reservation.nr_extents = 1;
241 return HYPERVISOR_memory_op(XENMEM_decrease_reservation, &reservation);
245 * This releases a chunk of memory and then does the identity map. It's used
246 * as a fallback if the remapping fails.
248 static void __init xen_set_identity_and_release_chunk(unsigned long start_pfn,
249 unsigned long end_pfn, unsigned long nr_pages)
251 unsigned long pfn, end;
254 WARN_ON(start_pfn > end_pfn);
256 /* Release pages first. */
257 end = min(end_pfn, nr_pages);
258 for (pfn = start_pfn; pfn < end; pfn++) {
259 unsigned long mfn = pfn_to_mfn(pfn);
261 /* Make sure pfn exists to start with */
262 if (mfn == INVALID_P2M_ENTRY || mfn_to_pfn(mfn) != pfn)
265 ret = xen_free_mfn(mfn);
266 WARN(ret != 1, "Failed to release pfn %lx err=%d\n", pfn, ret);
269 xen_released_pages++;
270 if (!__set_phys_to_machine(pfn, INVALID_P2M_ENTRY))
276 set_phys_range_identity(start_pfn, end_pfn);
280 * Helper function to update the p2m and m2p tables and kernel mapping.
282 static void __init xen_update_mem_tables(unsigned long pfn, unsigned long mfn)
284 struct mmu_update update = {
285 .ptr = ((uint64_t)mfn << PAGE_SHIFT) | MMU_MACHPHYS_UPDATE,
290 if (!set_phys_to_machine(pfn, mfn)) {
291 WARN(1, "Failed to set p2m mapping for pfn=%ld mfn=%ld\n",
297 if (HYPERVISOR_mmu_update(&update, 1, NULL, DOMID_SELF) < 0) {
298 WARN(1, "Failed to set m2p mapping for mfn=%ld pfn=%ld\n",
303 /* Update kernel mapping, but not for highmem. */
304 if (pfn >= PFN_UP(__pa(high_memory - 1)))
307 if (HYPERVISOR_update_va_mapping((unsigned long)__va(pfn << PAGE_SHIFT),
308 mfn_pte(mfn, PAGE_KERNEL), 0)) {
309 WARN(1, "Failed to update kernel mapping for mfn=%ld pfn=%ld\n",
316 * This function updates the p2m and m2p tables with an identity map from
317 * start_pfn to start_pfn+size and prepares remapping the underlying RAM of the
318 * original allocation at remap_pfn. The information needed for remapping is
319 * saved in the memory itself to avoid the need for allocating buffers. The
320 * complete remap information is contained in a list of MFNs each containing
321 * up to REMAP_SIZE MFNs and the start target PFN for doing the remap.
322 * This enables us to preserve the original mfn sequence while doing the
323 * remapping at a time when the memory management is capable of allocating
324 * virtual and physical memory in arbitrary amounts, see 'xen_remap_memory' and
327 static void __init xen_do_set_identity_and_remap_chunk(
328 unsigned long start_pfn, unsigned long size, unsigned long remap_pfn)
330 unsigned long buf = (unsigned long)&xen_remap_buf;
331 unsigned long mfn_save, mfn;
332 unsigned long ident_pfn_iter, remap_pfn_iter;
333 unsigned long ident_end_pfn = start_pfn + size;
334 unsigned long left = size;
335 unsigned int i, chunk;
339 BUG_ON(xen_feature(XENFEAT_auto_translated_physmap));
341 mfn_save = virt_to_mfn(buf);
343 for (ident_pfn_iter = start_pfn, remap_pfn_iter = remap_pfn;
344 ident_pfn_iter < ident_end_pfn;
345 ident_pfn_iter += REMAP_SIZE, remap_pfn_iter += REMAP_SIZE) {
346 chunk = (left < REMAP_SIZE) ? left : REMAP_SIZE;
348 /* Map first pfn to xen_remap_buf */
349 mfn = pfn_to_mfn(ident_pfn_iter);
350 set_pte_mfn(buf, mfn, PAGE_KERNEL);
352 /* Save mapping information in page */
353 xen_remap_buf.next_area_mfn = xen_remap_mfn;
354 xen_remap_buf.target_pfn = remap_pfn_iter;
355 xen_remap_buf.size = chunk;
356 for (i = 0; i < chunk; i++)
357 xen_remap_buf.mfns[i] = pfn_to_mfn(ident_pfn_iter + i);
359 /* Put remap buf into list. */
362 /* Set identity map */
363 set_phys_range_identity(ident_pfn_iter, ident_pfn_iter + chunk);
368 /* Restore old xen_remap_buf mapping */
369 set_pte_mfn(buf, mfn_save, PAGE_KERNEL);
373 * This function takes a contiguous pfn range that needs to be identity mapped
376 * 1) Finds a new range of pfns to use to remap based on E820 and remap_pfn.
377 * 2) Calls the do_ function to actually do the mapping/remapping work.
379 * The goal is to not allocate additional memory but to remap the existing
380 * pages. In the case of an error the underlying memory is simply released back
381 * to Xen and not remapped.
383 static unsigned long __init xen_set_identity_and_remap_chunk(
384 unsigned long start_pfn, unsigned long end_pfn, unsigned long nr_pages,
385 unsigned long remap_pfn)
389 unsigned long n = end_pfn - start_pfn;
392 unsigned long cur_pfn = start_pfn + i;
393 unsigned long left = n - i;
394 unsigned long size = left;
395 unsigned long remap_range_size;
397 /* Do not remap pages beyond the current allocation */
398 if (cur_pfn >= nr_pages) {
399 /* Identity map remaining pages */
400 set_phys_range_identity(cur_pfn, cur_pfn + size);
403 if (cur_pfn + size > nr_pages)
404 size = nr_pages - cur_pfn;
406 remap_range_size = xen_find_pfn_range(&remap_pfn);
407 if (!remap_range_size) {
408 pr_warning("Unable to find available pfn range, not remapping identity pages\n");
409 xen_set_identity_and_release_chunk(cur_pfn,
410 cur_pfn + left, nr_pages);
413 /* Adjust size to fit in current e820 RAM region */
414 if (size > remap_range_size)
415 size = remap_range_size;
417 xen_do_set_identity_and_remap_chunk(cur_pfn, size, remap_pfn);
419 /* Update variables to reflect new mappings. */
425 * If the PFNs are currently mapped, the VA mapping also needs
426 * to be updated to be 1:1.
428 for (pfn = start_pfn; pfn <= max_pfn_mapped && pfn < end_pfn; pfn++)
429 (void)HYPERVISOR_update_va_mapping(
430 (unsigned long)__va(pfn << PAGE_SHIFT),
431 mfn_pte(pfn, PAGE_KERNEL_IO), 0);
436 static void __init xen_set_identity_and_remap(unsigned long nr_pages)
438 phys_addr_t start = 0;
439 unsigned long last_pfn = nr_pages;
440 const struct e820entry *entry = xen_e820_map;
444 * Combine non-RAM regions and gaps until a RAM region (or the
445 * end of the map) is reached, then set the 1:1 map and
446 * remap the memory in those non-RAM regions.
448 * The combined non-RAM regions are rounded to a whole number
449 * of pages so any partial pages are accessible via the 1:1
450 * mapping. This is needed for some BIOSes that put (for
451 * example) the DMI tables in a reserved region that begins on
452 * a non-page boundary.
454 for (i = 0; i < xen_e820_map_entries; i++, entry++) {
455 phys_addr_t end = entry->addr + entry->size;
456 if (entry->type == E820_RAM || i == xen_e820_map_entries - 1) {
457 unsigned long start_pfn = PFN_DOWN(start);
458 unsigned long end_pfn = PFN_UP(end);
460 if (entry->type == E820_RAM)
461 end_pfn = PFN_UP(entry->addr);
463 if (start_pfn < end_pfn)
464 last_pfn = xen_set_identity_and_remap_chunk(
465 start_pfn, end_pfn, nr_pages,
471 pr_info("Released %ld page(s)\n", xen_released_pages);
475 * Remap the memory prepared in xen_do_set_identity_and_remap_chunk().
476 * The remap information (which mfn remap to which pfn) is contained in the
477 * to be remapped memory itself in a linked list anchored at xen_remap_mfn.
478 * This scheme allows to remap the different chunks in arbitrary order while
479 * the resulting mapping will be independant from the order.
481 void __init xen_remap_memory(void)
483 unsigned long buf = (unsigned long)&xen_remap_buf;
484 unsigned long mfn_save, mfn, pfn;
485 unsigned long remapped = 0;
487 unsigned long pfn_s = ~0UL;
488 unsigned long len = 0;
490 mfn_save = virt_to_mfn(buf);
492 while (xen_remap_mfn != INVALID_P2M_ENTRY) {
493 /* Map the remap information */
494 set_pte_mfn(buf, xen_remap_mfn, PAGE_KERNEL);
496 BUG_ON(xen_remap_mfn != xen_remap_buf.mfns[0]);
498 pfn = xen_remap_buf.target_pfn;
499 for (i = 0; i < xen_remap_buf.size; i++) {
500 mfn = xen_remap_buf.mfns[i];
501 xen_update_mem_tables(pfn, mfn);
505 if (pfn_s == ~0UL || pfn == pfn_s) {
506 pfn_s = xen_remap_buf.target_pfn;
507 len += xen_remap_buf.size;
508 } else if (pfn_s + len == xen_remap_buf.target_pfn) {
509 len += xen_remap_buf.size;
511 xen_del_extra_mem(PFN_PHYS(pfn_s), PFN_PHYS(len));
512 pfn_s = xen_remap_buf.target_pfn;
513 len = xen_remap_buf.size;
517 xen_remap_mfn = xen_remap_buf.next_area_mfn;
520 if (pfn_s != ~0UL && len)
521 xen_del_extra_mem(PFN_PHYS(pfn_s), PFN_PHYS(len));
523 set_pte_mfn(buf, mfn_save, PAGE_KERNEL);
525 pr_info("Remapped %ld page(s)\n", remapped);
528 static unsigned long __init xen_get_pages_limit(void)
533 limit = GB(64) / PAGE_SIZE;
536 if (!xen_initial_domain() && xen_512gb_limit)
537 limit = GB(512) / PAGE_SIZE;
542 static unsigned long __init xen_get_max_pages(void)
544 unsigned long max_pages, limit;
545 domid_t domid = DOMID_SELF;
548 limit = xen_get_pages_limit();
552 * For the initial domain we use the maximum reservation as
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
560 if (xen_initial_domain()) {
561 ret = HYPERVISOR_memory_op(XENMEM_maximum_reservation, &domid);
566 return min(max_pages, limit);
569 static void __init xen_align_and_add_e820_region(phys_addr_t start,
570 phys_addr_t size, int type)
572 phys_addr_t end = start + size;
574 /* Align RAM regions to page boundaries. */
575 if (type == E820_RAM) {
576 start = PAGE_ALIGN(start);
577 end &= ~((phys_addr_t)PAGE_SIZE - 1);
580 e820_add_region(start, end - start, type);
583 static void __init xen_ignore_unusable(void)
585 struct e820entry *entry = xen_e820_map;
588 for (i = 0; i < xen_e820_map_entries; i++, entry++) {
589 if (entry->type == E820_UNUSABLE)
590 entry->type = E820_RAM;
594 static unsigned long __init xen_count_remap_pages(unsigned long max_pfn)
596 unsigned long extra = 0;
597 const struct e820entry *entry = xen_e820_map;
600 for (i = 0; i < xen_e820_map_entries; i++, entry++) {
601 unsigned long start_pfn = PFN_DOWN(entry->addr);
602 unsigned long end_pfn = PFN_UP(entry->addr + entry->size);
604 if (start_pfn >= max_pfn)
606 if (entry->type == E820_RAM)
608 if (end_pfn >= max_pfn)
610 extra += end_pfn - start_pfn;
616 bool __init xen_is_e820_reserved(phys_addr_t start, phys_addr_t size)
618 struct e820entry *entry;
626 entry = xen_e820_map;
628 for (mapcnt = 0; mapcnt < xen_e820_map_entries; mapcnt++) {
629 if (entry->type == E820_RAM && entry->addr <= start &&
630 (entry->addr + entry->size) >= end)
640 * Find a free area in physical memory not yet reserved and compliant with
642 * Used to relocate pre-allocated areas like initrd or p2m list which are in
643 * conflict with the to be used E820 map.
644 * In case no area is found, return 0. Otherwise return the physical address
645 * of the area which is already reserved for convenience.
647 phys_addr_t __init xen_find_free_area(phys_addr_t size)
650 phys_addr_t addr, start;
651 struct e820entry *entry = xen_e820_map;
653 for (mapcnt = 0; mapcnt < xen_e820_map_entries; mapcnt++, entry++) {
654 if (entry->type != E820_RAM || entry->size < size)
657 for (addr = start; addr < start + size; addr += PAGE_SIZE) {
658 if (!memblock_is_reserved(addr))
660 start = addr + PAGE_SIZE;
661 if (start + size > entry->addr + entry->size)
664 if (addr >= start + size) {
665 memblock_reserve(start, size);
674 * Like memcpy, but with physical addresses for dest and src.
676 static void __init xen_phys_memcpy(phys_addr_t dest, phys_addr_t src,
679 phys_addr_t dest_off, src_off, dest_len, src_len, len;
683 dest_off = dest & ~PAGE_MASK;
684 src_off = src & ~PAGE_MASK;
686 if (dest_len > (NR_FIX_BTMAPS << PAGE_SHIFT) - dest_off)
687 dest_len = (NR_FIX_BTMAPS << PAGE_SHIFT) - dest_off;
689 if (src_len > (NR_FIX_BTMAPS << PAGE_SHIFT) - src_off)
690 src_len = (NR_FIX_BTMAPS << PAGE_SHIFT) - src_off;
691 len = min(dest_len, src_len);
692 to = early_memremap(dest - dest_off, dest_len + dest_off);
693 from = early_memremap(src - src_off, src_len + src_off);
694 memcpy(to, from, len);
695 early_memunmap(to, dest_len + dest_off);
696 early_memunmap(from, src_len + src_off);
704 * Reserve Xen mfn_list.
706 static void __init xen_reserve_xen_mfnlist(void)
708 phys_addr_t start, size;
710 if (xen_start_info->mfn_list >= __START_KERNEL_map) {
711 start = __pa(xen_start_info->mfn_list);
712 size = PFN_ALIGN(xen_start_info->nr_pages *
713 sizeof(unsigned long));
715 start = PFN_PHYS(xen_start_info->first_p2m_pfn);
716 size = PFN_PHYS(xen_start_info->nr_p2m_frames);
719 if (!xen_is_e820_reserved(start, size)) {
720 memblock_reserve(start, size);
726 * Relocating the p2m on 32 bit system to an arbitrary virtual address
727 * is not supported, so just give up.
729 xen_raw_console_write("Xen hypervisor allocated p2m list conflicts with E820 map\n");
737 * machine_specific_memory_setup - Hook for machine specific memory setup.
739 char * __init xen_memory_setup(void)
741 unsigned long max_pfn;
742 phys_addr_t mem_end, addr, size, chunk_size;
745 struct xen_memory_map memmap;
746 unsigned long max_pages;
747 unsigned long extra_pages = 0;
752 max_pfn = xen_get_pages_limit();
753 max_pfn = min(max_pfn, xen_start_info->nr_pages);
754 mem_end = PFN_PHYS(max_pfn);
756 memmap.nr_entries = E820MAX;
757 set_xen_guest_handle(memmap.buffer, xen_e820_map);
759 op = xen_initial_domain() ?
760 XENMEM_machine_memory_map :
762 rc = HYPERVISOR_memory_op(op, &memmap);
764 BUG_ON(xen_initial_domain());
765 memmap.nr_entries = 1;
766 xen_e820_map[0].addr = 0ULL;
767 xen_e820_map[0].size = mem_end;
768 /* 8MB slack (to balance backend allocations). */
769 xen_e820_map[0].size += 8ULL << 20;
770 xen_e820_map[0].type = E820_RAM;
774 BUG_ON(memmap.nr_entries == 0);
775 xen_e820_map_entries = memmap.nr_entries;
778 * Xen won't allow a 1:1 mapping to be created to UNUSABLE
779 * regions, so if we're using the machine memory map leave the
780 * region as RAM as it is in the pseudo-physical map.
782 * UNUSABLE regions in domUs are not handled and will need
783 * a patch in the future.
785 if (xen_initial_domain())
786 xen_ignore_unusable();
788 /* Make sure the Xen-supplied memory map is well-ordered. */
789 sanitize_e820_map(xen_e820_map, xen_e820_map_entries,
790 &xen_e820_map_entries);
792 max_pages = xen_get_max_pages();
793 if (max_pages > max_pfn)
794 extra_pages += max_pages - max_pfn;
796 /* How many extra pages do we need due to remapping? */
797 extra_pages += xen_count_remap_pages(max_pfn);
800 * Clamp the amount of extra memory to a EXTRA_MEM_RATIO
801 * factor the base size. On non-highmem systems, the base
802 * size is the full initial memory allocation; on highmem it
803 * is limited to the max size of lowmem, so that it doesn't
804 * get completely filled.
806 * Make sure we have no memory above max_pages, as this area
807 * isn't handled by the p2m management.
809 * In principle there could be a problem in lowmem systems if
810 * the initial memory is also very large with respect to
811 * lowmem, but we won't try to deal with that here.
813 extra_pages = min3(EXTRA_MEM_RATIO * min(max_pfn, PFN_DOWN(MAXMEM)),
814 extra_pages, max_pages - max_pfn);
816 addr = xen_e820_map[0].addr;
817 size = xen_e820_map[0].size;
818 while (i < xen_e820_map_entries) {
820 type = xen_e820_map[i].type;
822 if (type == E820_RAM) {
823 if (addr < mem_end) {
824 chunk_size = min(size, mem_end - addr);
825 } else if (extra_pages) {
826 chunk_size = min(size, PFN_PHYS(extra_pages));
827 extra_pages -= PFN_DOWN(chunk_size);
828 xen_add_extra_mem(addr, chunk_size);
829 xen_max_p2m_pfn = PFN_DOWN(addr + chunk_size);
831 type = E820_UNUSABLE;
834 xen_align_and_add_e820_region(addr, chunk_size, type);
840 if (i < xen_e820_map_entries) {
841 addr = xen_e820_map[i].addr;
842 size = xen_e820_map[i].size;
848 * Set the rest as identity mapped, in case PCI BARs are
851 set_phys_range_identity(addr / PAGE_SIZE, ~0ul);
854 * In domU, the ISA region is normal, usable memory, but we
855 * reserve ISA memory anyway because too many things poke
858 e820_add_region(ISA_START_ADDRESS, ISA_END_ADDRESS - ISA_START_ADDRESS,
861 sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
864 * Check whether the kernel itself conflicts with the target E820 map.
865 * Failing now is better than running into weird problems later due
866 * to relocating (and even reusing) pages with kernel text or data.
868 if (xen_is_e820_reserved(__pa_symbol(_text),
869 __pa_symbol(__bss_stop) - __pa_symbol(_text))) {
870 xen_raw_console_write("Xen hypervisor allocated kernel memory conflicts with E820 map\n");
875 * Check for a conflict of the hypervisor supplied page tables with
876 * the target E820 map.
880 xen_reserve_xen_mfnlist();
882 /* Check for a conflict of the initrd with the target E820 map. */
883 if (xen_is_e820_reserved(boot_params.hdr.ramdisk_image,
884 boot_params.hdr.ramdisk_size)) {
885 phys_addr_t new_area, start, size;
887 new_area = xen_find_free_area(boot_params.hdr.ramdisk_size);
889 xen_raw_console_write("Can't find new memory area for initrd needed due to E820 map conflict\n");
893 start = boot_params.hdr.ramdisk_image;
894 size = boot_params.hdr.ramdisk_size;
895 xen_phys_memcpy(new_area, start, size);
896 pr_info("initrd moved from [mem %#010llx-%#010llx] to [mem %#010llx-%#010llx]\n",
897 start, start + size, new_area, new_area + size);
898 memblock_free(start, size);
899 boot_params.hdr.ramdisk_image = new_area;
900 boot_params.ext_ramdisk_image = new_area >> 32;
904 * Set identity map on non-RAM pages and prepare remapping the
907 xen_set_identity_and_remap(max_pfn);
913 * Machine specific memory setup for auto-translated guests.
915 char * __init xen_auto_xlated_memory_setup(void)
917 struct xen_memory_map memmap;
921 memmap.nr_entries = E820MAX;
922 set_xen_guest_handle(memmap.buffer, xen_e820_map);
924 rc = HYPERVISOR_memory_op(XENMEM_memory_map, &memmap);
926 panic("No memory map (%d)\n", rc);
928 xen_e820_map_entries = memmap.nr_entries;
930 sanitize_e820_map(xen_e820_map, ARRAY_SIZE(xen_e820_map),
931 &xen_e820_map_entries);
933 for (i = 0; i < xen_e820_map_entries; i++)
934 e820_add_region(xen_e820_map[i].addr, xen_e820_map[i].size,
935 xen_e820_map[i].type);
937 /* Remove p2m info, it is not needed. */
938 xen_start_info->mfn_list = 0;
939 xen_start_info->first_p2m_pfn = 0;
940 xen_start_info->nr_p2m_frames = 0;
946 * Set the bit indicating "nosegneg" library variants should be used.
947 * We only need to bother in pure 32-bit mode; compat 32-bit processes
948 * can have un-truncated segments, so wrapping around is allowed.
950 static void __init fiddle_vdso(void)
954 * This could be called before selected_vdso32 is initialized, so
955 * just fiddle with both possible images. vdso_image_32_syscall
956 * can't be selected, since it only exists on 64-bit systems.
959 mask = vdso_image_32_int80.data +
960 vdso_image_32_int80.sym_VDSO32_NOTE_MASK;
961 *mask |= 1 << VDSO_NOTE_NONEGSEG_BIT;
962 mask = vdso_image_32_sysenter.data +
963 vdso_image_32_sysenter.sym_VDSO32_NOTE_MASK;
964 *mask |= 1 << VDSO_NOTE_NONEGSEG_BIT;
968 static int register_callback(unsigned type, const void *func)
970 struct callback_register callback = {
972 .address = XEN_CALLBACK(__KERNEL_CS, func),
973 .flags = CALLBACKF_mask_events,
976 return HYPERVISOR_callback_op(CALLBACKOP_register, &callback);
979 void xen_enable_sysenter(void)
982 unsigned sysenter_feature;
985 sysenter_feature = X86_FEATURE_SEP;
987 sysenter_feature = X86_FEATURE_SYSENTER32;
990 if (!boot_cpu_has(sysenter_feature))
993 ret = register_callback(CALLBACKTYPE_sysenter, xen_sysenter_target);
995 setup_clear_cpu_cap(sysenter_feature);
998 void xen_enable_syscall(void)
1000 #ifdef CONFIG_X86_64
1003 ret = register_callback(CALLBACKTYPE_syscall, xen_syscall_target);
1005 printk(KERN_ERR "Failed to set syscall callback: %d\n", ret);
1006 /* Pretty fatal; 64-bit userspace has no other
1007 mechanism for syscalls. */
1010 if (boot_cpu_has(X86_FEATURE_SYSCALL32)) {
1011 ret = register_callback(CALLBACKTYPE_syscall32,
1012 xen_syscall32_target);
1014 setup_clear_cpu_cap(X86_FEATURE_SYSCALL32);
1016 #endif /* CONFIG_X86_64 */
1019 void __init xen_pvmmu_arch_setup(void)
1021 HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_4gb_segments);
1022 HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_writable_pagetables);
1024 HYPERVISOR_vm_assist(VMASST_CMD_enable,
1025 VMASST_TYPE_pae_extended_cr3);
1027 if (register_callback(CALLBACKTYPE_event, xen_hypervisor_callback) ||
1028 register_callback(CALLBACKTYPE_failsafe, xen_failsafe_callback))
1031 xen_enable_sysenter();
1032 xen_enable_syscall();
1035 /* This function is not called for HVM domains */
1036 void __init xen_arch_setup(void)
1038 xen_panic_handler_init();
1039 if (!xen_feature(XENFEAT_auto_translated_physmap))
1040 xen_pvmmu_arch_setup();
1043 if (!(xen_start_info->flags & SIF_INITDOMAIN)) {
1044 printk(KERN_INFO "ACPI in unprivileged domain disabled\n");
1049 memcpy(boot_command_line, xen_start_info->cmd_line,
1050 MAX_GUEST_CMDLINE > COMMAND_LINE_SIZE ?
1051 COMMAND_LINE_SIZE : MAX_GUEST_CMDLINE);
1053 /* Set up idle, making sure it calls safe_halt() pvop */
1056 WARN_ON(xen_set_default_idle());