2 * KVM guest address space mapping code
4 * Copyright IBM Corp. 2007, 2016
5 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
8 #include <linux/kernel.h>
10 #include <linux/swap.h>
11 #include <linux/smp.h>
12 #include <linux/spinlock.h>
13 #include <linux/slab.h>
14 #include <linux/swapops.h>
15 #include <linux/ksm.h>
16 #include <linux/mman.h>
18 #include <asm/pgtable.h>
19 #include <asm/pgalloc.h>
24 * gmap_alloc - allocate and initialize a guest address space
25 * @mm: pointer to the parent mm_struct
26 * @limit: maximum address of the gmap address space
28 * Returns a guest address space structure.
30 static struct gmap *gmap_alloc(unsigned long limit)
35 unsigned long etype, atype;
37 if (limit < (1UL << 31)) {
38 limit = (1UL << 31) - 1;
39 atype = _ASCE_TYPE_SEGMENT;
40 etype = _SEGMENT_ENTRY_EMPTY;
41 } else if (limit < (1UL << 42)) {
42 limit = (1UL << 42) - 1;
43 atype = _ASCE_TYPE_REGION3;
44 etype = _REGION3_ENTRY_EMPTY;
45 } else if (limit < (1UL << 53)) {
46 limit = (1UL << 53) - 1;
47 atype = _ASCE_TYPE_REGION2;
48 etype = _REGION2_ENTRY_EMPTY;
51 atype = _ASCE_TYPE_REGION1;
52 etype = _REGION1_ENTRY_EMPTY;
54 gmap = kzalloc(sizeof(struct gmap), GFP_KERNEL);
57 INIT_LIST_HEAD(&gmap->crst_list);
58 INIT_LIST_HEAD(&gmap->children);
59 INIT_LIST_HEAD(&gmap->pt_list);
60 INIT_RADIX_TREE(&gmap->guest_to_host, GFP_KERNEL);
61 INIT_RADIX_TREE(&gmap->host_to_guest, GFP_ATOMIC);
62 INIT_RADIX_TREE(&gmap->host_to_rmap, GFP_ATOMIC);
63 spin_lock_init(&gmap->guest_table_lock);
64 spin_lock_init(&gmap->shadow_lock);
65 atomic_set(&gmap->ref_count, 1);
66 page = alloc_pages(GFP_KERNEL, 2);
70 list_add(&page->lru, &gmap->crst_list);
71 table = (unsigned long *) page_to_phys(page);
72 crst_table_init(table, etype);
74 gmap->asce = atype | _ASCE_TABLE_LENGTH |
75 _ASCE_USER_BITS | __pa(table);
76 gmap->asce_end = limit;
86 * gmap_create - create a guest address space
87 * @mm: pointer to the parent mm_struct
88 * @limit: maximum size of the gmap address space
90 * Returns a guest address space structure.
92 struct gmap *gmap_create(struct mm_struct *mm, unsigned long limit)
96 gmap = gmap_alloc(limit);
100 spin_lock(&mm->context.gmap_lock);
101 list_add_rcu(&gmap->list, &mm->context.gmap_list);
102 spin_unlock(&mm->context.gmap_lock);
105 EXPORT_SYMBOL_GPL(gmap_create);
107 static void gmap_flush_tlb(struct gmap *gmap)
109 if (MACHINE_HAS_IDTE)
110 __tlb_flush_asce(gmap->mm, gmap->asce);
112 __tlb_flush_global();
115 static void gmap_radix_tree_free(struct radix_tree_root *root)
117 struct radix_tree_iter iter;
118 unsigned long indices[16];
123 /* A radix tree is freed by deleting all of its entries */
127 radix_tree_for_each_slot(slot, root, &iter, index) {
128 indices[nr] = iter.index;
132 for (i = 0; i < nr; i++) {
134 radix_tree_delete(root, index);
139 static void gmap_rmap_radix_tree_free(struct radix_tree_root *root)
141 struct gmap_rmap *rmap, *rnext, *head;
142 struct radix_tree_iter iter;
143 unsigned long indices[16];
148 /* A radix tree is freed by deleting all of its entries */
152 radix_tree_for_each_slot(slot, root, &iter, index) {
153 indices[nr] = iter.index;
157 for (i = 0; i < nr; i++) {
159 head = radix_tree_delete(root, index);
160 gmap_for_each_rmap_safe(rmap, rnext, head)
167 * gmap_free - free a guest address space
168 * @gmap: pointer to the guest address space structure
170 * No locks required. There are no references to this gmap anymore.
172 static void gmap_free(struct gmap *gmap)
174 struct page *page, *next;
176 /* Flush tlb of all gmaps (if not already done for shadows) */
177 if (!(gmap_is_shadow(gmap) && gmap->removed))
178 gmap_flush_tlb(gmap);
179 /* Free all segment & region tables. */
180 list_for_each_entry_safe(page, next, &gmap->crst_list, lru)
181 __free_pages(page, 2);
182 gmap_radix_tree_free(&gmap->guest_to_host);
183 gmap_radix_tree_free(&gmap->host_to_guest);
185 /* Free additional data for a shadow gmap */
186 if (gmap_is_shadow(gmap)) {
187 /* Free all page tables. */
188 list_for_each_entry_safe(page, next, &gmap->pt_list, lru)
189 page_table_free_pgste(page);
190 gmap_rmap_radix_tree_free(&gmap->host_to_rmap);
191 /* Release reference to the parent */
192 gmap_put(gmap->parent);
199 * gmap_get - increase reference counter for guest address space
200 * @gmap: pointer to the guest address space structure
202 * Returns the gmap pointer
204 struct gmap *gmap_get(struct gmap *gmap)
206 atomic_inc(&gmap->ref_count);
209 EXPORT_SYMBOL_GPL(gmap_get);
212 * gmap_put - decrease reference counter for guest address space
213 * @gmap: pointer to the guest address space structure
215 * If the reference counter reaches zero the guest address space is freed.
217 void gmap_put(struct gmap *gmap)
219 if (atomic_dec_return(&gmap->ref_count) == 0)
222 EXPORT_SYMBOL_GPL(gmap_put);
225 * gmap_remove - remove a guest address space but do not free it yet
226 * @gmap: pointer to the guest address space structure
228 void gmap_remove(struct gmap *gmap)
230 struct gmap *sg, *next;
232 /* Remove all shadow gmaps linked to this gmap */
233 if (!list_empty(&gmap->children)) {
234 spin_lock(&gmap->shadow_lock);
235 list_for_each_entry_safe(sg, next, &gmap->children, list) {
239 spin_unlock(&gmap->shadow_lock);
241 /* Remove gmap from the pre-mm list */
242 spin_lock(&gmap->mm->context.gmap_lock);
243 list_del_rcu(&gmap->list);
244 spin_unlock(&gmap->mm->context.gmap_lock);
249 EXPORT_SYMBOL_GPL(gmap_remove);
252 * gmap_enable - switch primary space to the guest address space
253 * @gmap: pointer to the guest address space structure
255 void gmap_enable(struct gmap *gmap)
257 S390_lowcore.gmap = (unsigned long) gmap;
259 EXPORT_SYMBOL_GPL(gmap_enable);
262 * gmap_disable - switch back to the standard primary address space
263 * @gmap: pointer to the guest address space structure
265 void gmap_disable(struct gmap *gmap)
267 S390_lowcore.gmap = 0UL;
269 EXPORT_SYMBOL_GPL(gmap_disable);
272 * gmap_alloc_table is assumed to be called with mmap_sem held
274 static int gmap_alloc_table(struct gmap *gmap, unsigned long *table,
275 unsigned long init, unsigned long gaddr)
280 /* since we dont free the gmap table until gmap_free we can unlock */
281 page = alloc_pages(GFP_KERNEL, 2);
284 new = (unsigned long *) page_to_phys(page);
285 crst_table_init(new, init);
286 spin_lock(&gmap->guest_table_lock);
287 if (*table & _REGION_ENTRY_INVALID) {
288 list_add(&page->lru, &gmap->crst_list);
289 *table = (unsigned long) new | _REGION_ENTRY_LENGTH |
290 (*table & _REGION_ENTRY_TYPE_MASK);
294 spin_unlock(&gmap->guest_table_lock);
296 __free_pages(page, 2);
301 * __gmap_segment_gaddr - find virtual address from segment pointer
302 * @entry: pointer to a segment table entry in the guest address space
304 * Returns the virtual address in the guest address space for the segment
306 static unsigned long __gmap_segment_gaddr(unsigned long *entry)
309 unsigned long offset, mask;
311 offset = (unsigned long) entry / sizeof(unsigned long);
312 offset = (offset & (PTRS_PER_PMD - 1)) * PMD_SIZE;
313 mask = ~(PTRS_PER_PMD * sizeof(pmd_t) - 1);
314 page = virt_to_page((void *)((unsigned long) entry & mask));
315 return page->index + offset;
319 * __gmap_unlink_by_vmaddr - unlink a single segment via a host address
320 * @gmap: pointer to the guest address space structure
321 * @vmaddr: address in the host process address space
323 * Returns 1 if a TLB flush is required
325 static int __gmap_unlink_by_vmaddr(struct gmap *gmap, unsigned long vmaddr)
327 unsigned long *entry;
330 BUG_ON(gmap_is_shadow(gmap));
331 spin_lock(&gmap->guest_table_lock);
332 entry = radix_tree_delete(&gmap->host_to_guest, vmaddr >> PMD_SHIFT);
334 flush = (*entry != _SEGMENT_ENTRY_INVALID);
335 *entry = _SEGMENT_ENTRY_INVALID;
337 spin_unlock(&gmap->guest_table_lock);
342 * __gmap_unmap_by_gaddr - unmap a single segment via a guest address
343 * @gmap: pointer to the guest address space structure
344 * @gaddr: address in the guest address space
346 * Returns 1 if a TLB flush is required
348 static int __gmap_unmap_by_gaddr(struct gmap *gmap, unsigned long gaddr)
350 unsigned long vmaddr;
352 vmaddr = (unsigned long) radix_tree_delete(&gmap->guest_to_host,
354 return vmaddr ? __gmap_unlink_by_vmaddr(gmap, vmaddr) : 0;
358 * gmap_unmap_segment - unmap segment from the guest address space
359 * @gmap: pointer to the guest address space structure
360 * @to: address in the guest address space
361 * @len: length of the memory area to unmap
363 * Returns 0 if the unmap succeeded, -EINVAL if not.
365 int gmap_unmap_segment(struct gmap *gmap, unsigned long to, unsigned long len)
370 BUG_ON(gmap_is_shadow(gmap));
371 if ((to | len) & (PMD_SIZE - 1))
373 if (len == 0 || to + len < to)
377 down_write(&gmap->mm->mmap_sem);
378 for (off = 0; off < len; off += PMD_SIZE)
379 flush |= __gmap_unmap_by_gaddr(gmap, to + off);
380 up_write(&gmap->mm->mmap_sem);
382 gmap_flush_tlb(gmap);
385 EXPORT_SYMBOL_GPL(gmap_unmap_segment);
388 * gmap_map_segment - map a segment to the guest address space
389 * @gmap: pointer to the guest address space structure
390 * @from: source address in the parent address space
391 * @to: target address in the guest address space
392 * @len: length of the memory area to map
394 * Returns 0 if the mmap succeeded, -EINVAL or -ENOMEM if not.
396 int gmap_map_segment(struct gmap *gmap, unsigned long from,
397 unsigned long to, unsigned long len)
402 BUG_ON(gmap_is_shadow(gmap));
403 if ((from | to | len) & (PMD_SIZE - 1))
405 if (len == 0 || from + len < from || to + len < to ||
406 from + len - 1 > TASK_MAX_SIZE || to + len - 1 > gmap->asce_end)
410 down_write(&gmap->mm->mmap_sem);
411 for (off = 0; off < len; off += PMD_SIZE) {
412 /* Remove old translation */
413 flush |= __gmap_unmap_by_gaddr(gmap, to + off);
414 /* Store new translation */
415 if (radix_tree_insert(&gmap->guest_to_host,
416 (to + off) >> PMD_SHIFT,
417 (void *) from + off))
420 up_write(&gmap->mm->mmap_sem);
422 gmap_flush_tlb(gmap);
425 gmap_unmap_segment(gmap, to, len);
428 EXPORT_SYMBOL_GPL(gmap_map_segment);
431 * __gmap_translate - translate a guest address to a user space address
432 * @gmap: pointer to guest mapping meta data structure
433 * @gaddr: guest address
435 * Returns user space address which corresponds to the guest address or
436 * -EFAULT if no such mapping exists.
437 * This function does not establish potentially missing page table entries.
438 * The mmap_sem of the mm that belongs to the address space must be held
439 * when this function gets called.
441 * Note: Can also be called for shadow gmaps.
443 unsigned long __gmap_translate(struct gmap *gmap, unsigned long gaddr)
445 unsigned long vmaddr;
447 vmaddr = (unsigned long)
448 radix_tree_lookup(&gmap->guest_to_host, gaddr >> PMD_SHIFT);
449 /* Note: guest_to_host is empty for a shadow gmap */
450 return vmaddr ? (vmaddr | (gaddr & ~PMD_MASK)) : -EFAULT;
452 EXPORT_SYMBOL_GPL(__gmap_translate);
455 * gmap_translate - translate a guest address to a user space address
456 * @gmap: pointer to guest mapping meta data structure
457 * @gaddr: guest address
459 * Returns user space address which corresponds to the guest address or
460 * -EFAULT if no such mapping exists.
461 * This function does not establish potentially missing page table entries.
463 unsigned long gmap_translate(struct gmap *gmap, unsigned long gaddr)
467 down_read(&gmap->mm->mmap_sem);
468 rc = __gmap_translate(gmap, gaddr);
469 up_read(&gmap->mm->mmap_sem);
472 EXPORT_SYMBOL_GPL(gmap_translate);
475 * gmap_unlink - disconnect a page table from the gmap shadow tables
476 * @gmap: pointer to guest mapping meta data structure
477 * @table: pointer to the host page table
478 * @vmaddr: vm address associated with the host page table
480 void gmap_unlink(struct mm_struct *mm, unsigned long *table,
481 unsigned long vmaddr)
487 list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) {
488 flush = __gmap_unlink_by_vmaddr(gmap, vmaddr);
490 gmap_flush_tlb(gmap);
496 * gmap_link - set up shadow page tables to connect a host to a guest address
497 * @gmap: pointer to guest mapping meta data structure
498 * @gaddr: guest address
499 * @vmaddr: vm address
501 * Returns 0 on success, -ENOMEM for out of memory conditions, and -EFAULT
502 * if the vm address is already mapped to a different guest segment.
503 * The mmap_sem of the mm that belongs to the address space must be held
504 * when this function gets called.
506 int __gmap_link(struct gmap *gmap, unsigned long gaddr, unsigned long vmaddr)
508 struct mm_struct *mm;
509 unsigned long *table;
516 BUG_ON(gmap_is_shadow(gmap));
517 /* Create higher level tables in the gmap page table */
519 if ((gmap->asce & _ASCE_TYPE_MASK) >= _ASCE_TYPE_REGION1) {
520 table += (gaddr >> 53) & 0x7ff;
521 if ((*table & _REGION_ENTRY_INVALID) &&
522 gmap_alloc_table(gmap, table, _REGION2_ENTRY_EMPTY,
523 gaddr & 0xffe0000000000000UL))
525 table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
527 if ((gmap->asce & _ASCE_TYPE_MASK) >= _ASCE_TYPE_REGION2) {
528 table += (gaddr >> 42) & 0x7ff;
529 if ((*table & _REGION_ENTRY_INVALID) &&
530 gmap_alloc_table(gmap, table, _REGION3_ENTRY_EMPTY,
531 gaddr & 0xfffffc0000000000UL))
533 table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
535 if ((gmap->asce & _ASCE_TYPE_MASK) >= _ASCE_TYPE_REGION3) {
536 table += (gaddr >> 31) & 0x7ff;
537 if ((*table & _REGION_ENTRY_INVALID) &&
538 gmap_alloc_table(gmap, table, _SEGMENT_ENTRY_EMPTY,
539 gaddr & 0xffffffff80000000UL))
541 table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
543 table += (gaddr >> 20) & 0x7ff;
544 /* Walk the parent mm page table */
546 pgd = pgd_offset(mm, vmaddr);
547 VM_BUG_ON(pgd_none(*pgd));
548 pud = pud_offset(pgd, vmaddr);
549 VM_BUG_ON(pud_none(*pud));
550 pmd = pmd_offset(pud, vmaddr);
551 VM_BUG_ON(pmd_none(*pmd));
552 /* large pmds cannot yet be handled */
555 /* Link gmap segment table entry location to page table. */
556 rc = radix_tree_preload(GFP_KERNEL);
559 ptl = pmd_lock(mm, pmd);
560 spin_lock(&gmap->guest_table_lock);
561 if (*table == _SEGMENT_ENTRY_INVALID) {
562 rc = radix_tree_insert(&gmap->host_to_guest,
563 vmaddr >> PMD_SHIFT, table);
565 *table = pmd_val(*pmd);
568 spin_unlock(&gmap->guest_table_lock);
570 radix_tree_preload_end();
575 * gmap_fault - resolve a fault on a guest address
576 * @gmap: pointer to guest mapping meta data structure
577 * @gaddr: guest address
578 * @fault_flags: flags to pass down to handle_mm_fault()
580 * Returns 0 on success, -ENOMEM for out of memory conditions, and -EFAULT
581 * if the vm address is already mapped to a different guest segment.
583 int gmap_fault(struct gmap *gmap, unsigned long gaddr,
584 unsigned int fault_flags)
586 unsigned long vmaddr;
590 down_read(&gmap->mm->mmap_sem);
594 vmaddr = __gmap_translate(gmap, gaddr);
595 if (IS_ERR_VALUE(vmaddr)) {
599 if (fixup_user_fault(current, gmap->mm, vmaddr, fault_flags,
605 * In the case that fixup_user_fault unlocked the mmap_sem during
606 * faultin redo __gmap_translate to not race with a map/unmap_segment.
611 rc = __gmap_link(gmap, gaddr, vmaddr);
613 up_read(&gmap->mm->mmap_sem);
616 EXPORT_SYMBOL_GPL(gmap_fault);
619 * this function is assumed to be called with mmap_sem held
621 void __gmap_zap(struct gmap *gmap, unsigned long gaddr)
623 unsigned long vmaddr;
627 /* Find the vm address for the guest address */
628 vmaddr = (unsigned long) radix_tree_lookup(&gmap->guest_to_host,
631 vmaddr |= gaddr & ~PMD_MASK;
632 /* Get pointer to the page table entry */
633 ptep = get_locked_pte(gmap->mm, vmaddr, &ptl);
635 ptep_zap_unused(gmap->mm, vmaddr, ptep, 0);
636 pte_unmap_unlock(ptep, ptl);
639 EXPORT_SYMBOL_GPL(__gmap_zap);
641 void gmap_discard(struct gmap *gmap, unsigned long from, unsigned long to)
643 unsigned long gaddr, vmaddr, size;
644 struct vm_area_struct *vma;
646 down_read(&gmap->mm->mmap_sem);
647 for (gaddr = from; gaddr < to;
648 gaddr = (gaddr + PMD_SIZE) & PMD_MASK) {
649 /* Find the vm address for the guest address */
650 vmaddr = (unsigned long)
651 radix_tree_lookup(&gmap->guest_to_host,
655 vmaddr |= gaddr & ~PMD_MASK;
656 /* Find vma in the parent mm */
657 vma = find_vma(gmap->mm, vmaddr);
658 size = min(to - gaddr, PMD_SIZE - (gaddr & ~PMD_MASK));
659 zap_page_range(vma, vmaddr, size, NULL);
661 up_read(&gmap->mm->mmap_sem);
663 EXPORT_SYMBOL_GPL(gmap_discard);
665 static LIST_HEAD(gmap_notifier_list);
666 static DEFINE_SPINLOCK(gmap_notifier_lock);
669 * gmap_register_pte_notifier - register a pte invalidation callback
670 * @nb: pointer to the gmap notifier block
672 void gmap_register_pte_notifier(struct gmap_notifier *nb)
674 spin_lock(&gmap_notifier_lock);
675 list_add_rcu(&nb->list, &gmap_notifier_list);
676 spin_unlock(&gmap_notifier_lock);
678 EXPORT_SYMBOL_GPL(gmap_register_pte_notifier);
681 * gmap_unregister_pte_notifier - remove a pte invalidation callback
682 * @nb: pointer to the gmap notifier block
684 void gmap_unregister_pte_notifier(struct gmap_notifier *nb)
686 spin_lock(&gmap_notifier_lock);
687 list_del_rcu(&nb->list);
688 spin_unlock(&gmap_notifier_lock);
691 EXPORT_SYMBOL_GPL(gmap_unregister_pte_notifier);
694 * gmap_call_notifier - call all registered invalidation callbacks
695 * @gmap: pointer to guest mapping meta data structure
696 * @start: start virtual address in the guest address space
697 * @end: end virtual address in the guest address space
699 static void gmap_call_notifier(struct gmap *gmap, unsigned long start,
702 struct gmap_notifier *nb;
704 list_for_each_entry(nb, &gmap_notifier_list, list)
705 nb->notifier_call(gmap, start, end);
709 * gmap_table_walk - walk the gmap page tables
710 * @gmap: pointer to guest mapping meta data structure
711 * @gaddr: virtual address in the guest address space
712 * @level: page table level to stop at
714 * Returns a table entry pointer for the given guest address and @level
715 * @level=0 : returns a pointer to a page table table entry (or NULL)
716 * @level=1 : returns a pointer to a segment table entry (or NULL)
717 * @level=2 : returns a pointer to a region-3 table entry (or NULL)
718 * @level=3 : returns a pointer to a region-2 table entry (or NULL)
719 * @level=4 : returns a pointer to a region-1 table entry (or NULL)
721 * Returns NULL if the gmap page tables could not be walked to the
724 * Note: Can also be called for shadow gmaps.
726 static inline unsigned long *gmap_table_walk(struct gmap *gmap,
727 unsigned long gaddr, int level)
729 unsigned long *table;
731 if ((gmap->asce & _ASCE_TYPE_MASK) + 4 < (level * 4))
733 if (gmap_is_shadow(gmap) && gmap->removed)
735 if (gaddr & (-1UL << (31 + ((gmap->asce & _ASCE_TYPE_MASK) >> 2)*11)))
738 switch (gmap->asce & _ASCE_TYPE_MASK) {
739 case _ASCE_TYPE_REGION1:
740 table += (gaddr >> 53) & 0x7ff;
743 if (*table & _REGION_ENTRY_INVALID)
745 table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
747 case _ASCE_TYPE_REGION2:
748 table += (gaddr >> 42) & 0x7ff;
751 if (*table & _REGION_ENTRY_INVALID)
753 table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
755 case _ASCE_TYPE_REGION3:
756 table += (gaddr >> 31) & 0x7ff;
759 if (*table & _REGION_ENTRY_INVALID)
761 table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
763 case _ASCE_TYPE_SEGMENT:
764 table += (gaddr >> 20) & 0x7ff;
767 if (*table & _REGION_ENTRY_INVALID)
769 table = (unsigned long *)(*table & _SEGMENT_ENTRY_ORIGIN);
770 table += (gaddr >> 12) & 0xff;
776 * gmap_pte_op_walk - walk the gmap page table, get the page table lock
777 * and return the pte pointer
778 * @gmap: pointer to guest mapping meta data structure
779 * @gaddr: virtual address in the guest address space
780 * @ptl: pointer to the spinlock pointer
782 * Returns a pointer to the locked pte for a guest address, or NULL
784 * Note: Can also be called for shadow gmaps.
786 static pte_t *gmap_pte_op_walk(struct gmap *gmap, unsigned long gaddr,
789 unsigned long *table;
791 if (gmap_is_shadow(gmap))
792 spin_lock(&gmap->guest_table_lock);
793 /* Walk the gmap page table, lock and get pte pointer */
794 table = gmap_table_walk(gmap, gaddr, 1); /* get segment pointer */
795 if (!table || *table & _SEGMENT_ENTRY_INVALID) {
796 if (gmap_is_shadow(gmap))
797 spin_unlock(&gmap->guest_table_lock);
800 if (gmap_is_shadow(gmap)) {
801 *ptl = &gmap->guest_table_lock;
802 return pte_offset_map((pmd_t *) table, gaddr);
804 return pte_alloc_map_lock(gmap->mm, (pmd_t *) table, gaddr, ptl);
808 * gmap_pte_op_fixup - force a page in and connect the gmap page table
809 * @gmap: pointer to guest mapping meta data structure
810 * @gaddr: virtual address in the guest address space
811 * @vmaddr: address in the host process address space
813 * Returns 0 if the caller can retry __gmap_translate (might fail again),
814 * -ENOMEM if out of memory and -EFAULT if anything goes wrong while fixing
815 * up or connecting the gmap page table.
817 static int gmap_pte_op_fixup(struct gmap *gmap, unsigned long gaddr,
818 unsigned long vmaddr)
820 struct mm_struct *mm = gmap->mm;
821 bool unlocked = false;
823 BUG_ON(gmap_is_shadow(gmap));
824 if (fixup_user_fault(current, mm, vmaddr, FAULT_FLAG_WRITE, &unlocked))
827 /* lost mmap_sem, caller has to retry __gmap_translate */
829 /* Connect the page tables */
830 return __gmap_link(gmap, gaddr, vmaddr);
834 * gmap_pte_op_end - release the page table lock
835 * @ptl: pointer to the spinlock pointer
837 static void gmap_pte_op_end(spinlock_t *ptl)
843 * gmap_protect_range - remove access rights to memory and set pgste bits
844 * @gmap: pointer to guest mapping meta data structure
845 * @gaddr: virtual address in the guest address space
847 * @prot: indicates access rights: PROT_NONE, PROT_READ or PROT_WRITE
848 * @bits: pgste notification bits to set
850 * Returns 0 if successfully protected, -ENOMEM if out of memory and
851 * -EFAULT if gaddr is invalid (or mapping for shadows is missing).
853 * Called with sg->mm->mmap_sem in read.
855 * Note: Can also be called for shadow gmaps.
857 static int gmap_protect_range(struct gmap *gmap, unsigned long gaddr,
858 unsigned long len, int prot, unsigned long bits)
860 unsigned long vmaddr;
867 ptep = gmap_pte_op_walk(gmap, gaddr, &ptl);
869 rc = ptep_force_prot(gmap->mm, gaddr, ptep, prot, bits);
870 gmap_pte_op_end(ptl);
873 vmaddr = __gmap_translate(gmap, gaddr);
874 if (IS_ERR_VALUE(vmaddr))
876 rc = gmap_pte_op_fixup(gmap, gaddr, vmaddr);
888 * gmap_mprotect_notify - change access rights for a range of ptes and
889 * call the notifier if any pte changes again
890 * @gmap: pointer to guest mapping meta data structure
891 * @gaddr: virtual address in the guest address space
893 * @prot: indicates access rights: PROT_NONE, PROT_READ or PROT_WRITE
895 * Returns 0 if for each page in the given range a gmap mapping exists,
896 * the new access rights could be set and the notifier could be armed.
897 * If the gmap mapping is missing for one or more pages -EFAULT is
898 * returned. If no memory could be allocated -ENOMEM is returned.
899 * This function establishes missing page table entries.
901 int gmap_mprotect_notify(struct gmap *gmap, unsigned long gaddr,
902 unsigned long len, int prot)
906 if ((gaddr & ~PAGE_MASK) || (len & ~PAGE_MASK) || gmap_is_shadow(gmap))
908 if (!MACHINE_HAS_ESOP && prot == PROT_READ)
910 down_read(&gmap->mm->mmap_sem);
911 rc = gmap_protect_range(gmap, gaddr, len, prot, PGSTE_IN_BIT);
912 up_read(&gmap->mm->mmap_sem);
915 EXPORT_SYMBOL_GPL(gmap_mprotect_notify);
918 * gmap_read_table - get an unsigned long value from a guest page table using
919 * absolute addressing, without marking the page referenced.
920 * @gmap: pointer to guest mapping meta data structure
921 * @gaddr: virtual address in the guest address space
922 * @val: pointer to the unsigned long value to return
924 * Returns 0 if the value was read, -ENOMEM if out of memory and -EFAULT
925 * if reading using the virtual address failed.
927 * Called with gmap->mm->mmap_sem in read.
929 int gmap_read_table(struct gmap *gmap, unsigned long gaddr, unsigned long *val)
931 unsigned long address, vmaddr;
938 ptep = gmap_pte_op_walk(gmap, gaddr, &ptl);
941 if (pte_present(pte) && (pte_val(pte) & _PAGE_READ)) {
942 address = pte_val(pte) & PAGE_MASK;
943 address += gaddr & ~PAGE_MASK;
944 *val = *(unsigned long *) address;
945 pte_val(*ptep) |= _PAGE_YOUNG;
946 /* Do *NOT* clear the _PAGE_INVALID bit! */
949 gmap_pte_op_end(ptl);
953 vmaddr = __gmap_translate(gmap, gaddr);
954 if (IS_ERR_VALUE(vmaddr)) {
958 rc = gmap_pte_op_fixup(gmap, gaddr, vmaddr);
964 EXPORT_SYMBOL_GPL(gmap_read_table);
967 * gmap_insert_rmap - add a rmap to the host_to_rmap radix tree
968 * @sg: pointer to the shadow guest address space structure
969 * @vmaddr: vm address associated with the rmap
970 * @rmap: pointer to the rmap structure
972 * Called with the sg->guest_table_lock
974 static inline void gmap_insert_rmap(struct gmap *sg, unsigned long vmaddr,
975 struct gmap_rmap *rmap)
979 BUG_ON(!gmap_is_shadow(sg));
980 slot = radix_tree_lookup_slot(&sg->host_to_rmap, vmaddr >> PAGE_SHIFT);
982 rmap->next = radix_tree_deref_slot_protected(slot,
983 &sg->guest_table_lock);
984 radix_tree_replace_slot(slot, rmap);
987 radix_tree_insert(&sg->host_to_rmap, vmaddr >> PAGE_SHIFT,
993 * gmap_protect_rmap - modify access rights to memory and create an rmap
994 * @sg: pointer to the shadow guest address space structure
995 * @raddr: rmap address in the shadow gmap
996 * @paddr: address in the parent guest address space
997 * @len: length of the memory area to protect
998 * @prot: indicates access rights: none, read-only or read-write
1000 * Returns 0 if successfully protected and the rmap was created, -ENOMEM
1001 * if out of memory and -EFAULT if paddr is invalid.
1003 static int gmap_protect_rmap(struct gmap *sg, unsigned long raddr,
1004 unsigned long paddr, unsigned long len, int prot)
1006 struct gmap *parent;
1007 struct gmap_rmap *rmap;
1008 unsigned long vmaddr;
1013 BUG_ON(!gmap_is_shadow(sg));
1014 parent = sg->parent;
1016 vmaddr = __gmap_translate(parent, paddr);
1017 if (IS_ERR_VALUE(vmaddr))
1019 rmap = kzalloc(sizeof(*rmap), GFP_KERNEL);
1022 rmap->raddr = raddr;
1023 rc = radix_tree_preload(GFP_KERNEL);
1029 ptep = gmap_pte_op_walk(parent, paddr, &ptl);
1031 spin_lock(&sg->guest_table_lock);
1032 rc = ptep_force_prot(parent->mm, paddr, ptep, prot,
1035 gmap_insert_rmap(sg, vmaddr, rmap);
1036 spin_unlock(&sg->guest_table_lock);
1037 gmap_pte_op_end(ptl);
1039 radix_tree_preload_end();
1042 rc = gmap_pte_op_fixup(parent, paddr, vmaddr);
1053 #define _SHADOW_RMAP_MASK 0x7
1054 #define _SHADOW_RMAP_REGION1 0x5
1055 #define _SHADOW_RMAP_REGION2 0x4
1056 #define _SHADOW_RMAP_REGION3 0x3
1057 #define _SHADOW_RMAP_SEGMENT 0x2
1058 #define _SHADOW_RMAP_PGTABLE 0x1
1061 * gmap_idte_one - invalidate a single region or segment table entry
1062 * @asce: region or segment table *origin* + table-type bits
1063 * @vaddr: virtual address to identify the table entry to flush
1065 * The invalid bit of a single region or segment table entry is set
1066 * and the associated TLB entries depending on the entry are flushed.
1067 * The table-type of the @asce identifies the portion of the @vaddr
1068 * that is used as the invalidation index.
1070 static inline void gmap_idte_one(unsigned long asce, unsigned long vaddr)
1073 " .insn rrf,0xb98e0000,%0,%1,0,0"
1074 : : "a" (asce), "a" (vaddr) : "cc", "memory");
1078 * gmap_unshadow_page - remove a page from a shadow page table
1079 * @sg: pointer to the shadow guest address space structure
1080 * @raddr: rmap address in the shadow guest address space
1082 * Called with the sg->guest_table_lock
1084 static void gmap_unshadow_page(struct gmap *sg, unsigned long raddr)
1086 unsigned long *table;
1088 BUG_ON(!gmap_is_shadow(sg));
1089 table = gmap_table_walk(sg, raddr, 0); /* get page table pointer */
1090 if (!table || *table & _PAGE_INVALID)
1092 gmap_call_notifier(sg, raddr, raddr + (1UL << 12) - 1);
1093 ptep_unshadow_pte(sg->mm, raddr, (pte_t *) table);
1097 * __gmap_unshadow_pgt - remove all entries from a shadow page table
1098 * @sg: pointer to the shadow guest address space structure
1099 * @raddr: rmap address in the shadow guest address space
1100 * @pgt: pointer to the start of a shadow page table
1102 * Called with the sg->guest_table_lock
1104 static void __gmap_unshadow_pgt(struct gmap *sg, unsigned long raddr,
1109 BUG_ON(!gmap_is_shadow(sg));
1110 for (i = 0; i < 256; i++, raddr += 1UL << 12)
1111 pgt[i] = _PAGE_INVALID;
1115 * gmap_unshadow_pgt - remove a shadow page table from a segment entry
1116 * @sg: pointer to the shadow guest address space structure
1117 * @raddr: address in the shadow guest address space
1119 * Called with the sg->guest_table_lock
1121 static void gmap_unshadow_pgt(struct gmap *sg, unsigned long raddr)
1123 unsigned long sto, *ste, *pgt;
1126 BUG_ON(!gmap_is_shadow(sg));
1127 ste = gmap_table_walk(sg, raddr, 1); /* get segment pointer */
1128 if (!ste || *ste & _SEGMENT_ENTRY_INVALID)
1130 gmap_call_notifier(sg, raddr, raddr + (1UL << 20) - 1);
1131 sto = (unsigned long) (ste - ((raddr >> 20) & 0x7ff));
1132 gmap_idte_one(sto | _ASCE_TYPE_SEGMENT, raddr);
1133 pgt = (unsigned long *)(*ste & _SEGMENT_ENTRY_ORIGIN);
1134 *ste = _SEGMENT_ENTRY_EMPTY;
1135 __gmap_unshadow_pgt(sg, raddr, pgt);
1136 /* Free page table */
1137 page = pfn_to_page(__pa(pgt) >> PAGE_SHIFT);
1138 list_del(&page->lru);
1139 page_table_free_pgste(page);
1143 * __gmap_unshadow_sgt - remove all entries from a shadow segment table
1144 * @sg: pointer to the shadow guest address space structure
1145 * @raddr: rmap address in the shadow guest address space
1146 * @sgt: pointer to the start of a shadow segment table
1148 * Called with the sg->guest_table_lock
1150 static void __gmap_unshadow_sgt(struct gmap *sg, unsigned long raddr,
1153 unsigned long asce, *pgt;
1157 BUG_ON(!gmap_is_shadow(sg));
1158 asce = (unsigned long) sgt | _ASCE_TYPE_SEGMENT;
1159 for (i = 0; i < 2048; i++, raddr += 1UL << 20) {
1160 if (sgt[i] & _SEGMENT_ENTRY_INVALID)
1162 pgt = (unsigned long *)(sgt[i] & _REGION_ENTRY_ORIGIN);
1163 sgt[i] = _SEGMENT_ENTRY_EMPTY;
1164 __gmap_unshadow_pgt(sg, raddr, pgt);
1165 /* Free page table */
1166 page = pfn_to_page(__pa(pgt) >> PAGE_SHIFT);
1167 list_del(&page->lru);
1168 page_table_free_pgste(page);
1173 * gmap_unshadow_sgt - remove a shadow segment table from a region-3 entry
1174 * @sg: pointer to the shadow guest address space structure
1175 * @raddr: rmap address in the shadow guest address space
1177 * Called with the shadow->guest_table_lock
1179 static void gmap_unshadow_sgt(struct gmap *sg, unsigned long raddr)
1181 unsigned long r3o, *r3e, *sgt;
1184 BUG_ON(!gmap_is_shadow(sg));
1185 r3e = gmap_table_walk(sg, raddr, 2); /* get region-3 pointer */
1186 if (!r3e || *r3e & _REGION_ENTRY_INVALID)
1188 gmap_call_notifier(sg, raddr, raddr + (1UL << 31) - 1);
1189 r3o = (unsigned long) (r3e - ((raddr >> 31) & 0x7ff));
1190 gmap_idte_one(r3o | _ASCE_TYPE_REGION3, raddr);
1191 sgt = (unsigned long *)(*r3e & _REGION_ENTRY_ORIGIN);
1192 *r3e = _REGION3_ENTRY_EMPTY;
1193 __gmap_unshadow_sgt(sg, raddr, sgt);
1194 /* Free segment table */
1195 page = pfn_to_page(__pa(sgt) >> PAGE_SHIFT);
1196 list_del(&page->lru);
1197 __free_pages(page, 2);
1201 * __gmap_unshadow_r3t - remove all entries from a shadow region-3 table
1202 * @sg: pointer to the shadow guest address space structure
1203 * @raddr: address in the shadow guest address space
1204 * @r3t: pointer to the start of a shadow region-3 table
1206 * Called with the sg->guest_table_lock
1208 static void __gmap_unshadow_r3t(struct gmap *sg, unsigned long raddr,
1211 unsigned long asce, *sgt;
1215 BUG_ON(!gmap_is_shadow(sg));
1216 asce = (unsigned long) r3t | _ASCE_TYPE_REGION3;
1217 for (i = 0; i < 2048; i++, raddr += 1UL << 31) {
1218 if (r3t[i] & _REGION_ENTRY_INVALID)
1220 sgt = (unsigned long *)(r3t[i] & _REGION_ENTRY_ORIGIN);
1221 r3t[i] = _REGION3_ENTRY_EMPTY;
1222 __gmap_unshadow_sgt(sg, raddr, sgt);
1223 /* Free segment table */
1224 page = pfn_to_page(__pa(sgt) >> PAGE_SHIFT);
1225 list_del(&page->lru);
1226 __free_pages(page, 2);
1231 * gmap_unshadow_r3t - remove a shadow region-3 table from a region-2 entry
1232 * @sg: pointer to the shadow guest address space structure
1233 * @raddr: rmap address in the shadow guest address space
1235 * Called with the sg->guest_table_lock
1237 static void gmap_unshadow_r3t(struct gmap *sg, unsigned long raddr)
1239 unsigned long r2o, *r2e, *r3t;
1242 BUG_ON(!gmap_is_shadow(sg));
1243 r2e = gmap_table_walk(sg, raddr, 3); /* get region-2 pointer */
1244 if (!r2e || *r2e & _REGION_ENTRY_INVALID)
1246 gmap_call_notifier(sg, raddr, raddr + (1UL << 42) - 1);
1247 r2o = (unsigned long) (r2e - ((raddr >> 42) & 0x7ff));
1248 gmap_idte_one(r2o | _ASCE_TYPE_REGION2, raddr);
1249 r3t = (unsigned long *)(*r2e & _REGION_ENTRY_ORIGIN);
1250 *r2e = _REGION2_ENTRY_EMPTY;
1251 __gmap_unshadow_r3t(sg, raddr, r3t);
1252 /* Free region 3 table */
1253 page = pfn_to_page(__pa(r3t) >> PAGE_SHIFT);
1254 list_del(&page->lru);
1255 __free_pages(page, 2);
1259 * __gmap_unshadow_r2t - remove all entries from a shadow region-2 table
1260 * @sg: pointer to the shadow guest address space structure
1261 * @raddr: rmap address in the shadow guest address space
1262 * @r2t: pointer to the start of a shadow region-2 table
1264 * Called with the sg->guest_table_lock
1266 static void __gmap_unshadow_r2t(struct gmap *sg, unsigned long raddr,
1269 unsigned long asce, *r3t;
1273 BUG_ON(!gmap_is_shadow(sg));
1274 asce = (unsigned long) r2t | _ASCE_TYPE_REGION2;
1275 for (i = 0; i < 2048; i++, raddr += 1UL << 42) {
1276 if (r2t[i] & _REGION_ENTRY_INVALID)
1278 r3t = (unsigned long *)(r2t[i] & _REGION_ENTRY_ORIGIN);
1279 r2t[i] = _REGION2_ENTRY_EMPTY;
1280 __gmap_unshadow_r3t(sg, raddr, r3t);
1281 /* Free region 3 table */
1282 page = pfn_to_page(__pa(r3t) >> PAGE_SHIFT);
1283 list_del(&page->lru);
1284 __free_pages(page, 2);
1289 * gmap_unshadow_r2t - remove a shadow region-2 table from a region-1 entry
1290 * @sg: pointer to the shadow guest address space structure
1291 * @raddr: rmap address in the shadow guest address space
1293 * Called with the sg->guest_table_lock
1295 static void gmap_unshadow_r2t(struct gmap *sg, unsigned long raddr)
1297 unsigned long r1o, *r1e, *r2t;
1300 BUG_ON(!gmap_is_shadow(sg));
1301 r1e = gmap_table_walk(sg, raddr, 4); /* get region-1 pointer */
1302 if (!r1e || *r1e & _REGION_ENTRY_INVALID)
1304 gmap_call_notifier(sg, raddr, raddr + (1UL << 53) - 1);
1305 r1o = (unsigned long) (r1e - ((raddr >> 53) & 0x7ff));
1306 gmap_idte_one(r1o | _ASCE_TYPE_REGION1, raddr);
1307 r2t = (unsigned long *)(*r1e & _REGION_ENTRY_ORIGIN);
1308 *r1e = _REGION1_ENTRY_EMPTY;
1309 __gmap_unshadow_r2t(sg, raddr, r2t);
1310 /* Free region 2 table */
1311 page = pfn_to_page(__pa(r2t) >> PAGE_SHIFT);
1312 list_del(&page->lru);
1313 __free_pages(page, 2);
1317 * __gmap_unshadow_r1t - remove all entries from a shadow region-1 table
1318 * @sg: pointer to the shadow guest address space structure
1319 * @raddr: rmap address in the shadow guest address space
1320 * @r1t: pointer to the start of a shadow region-1 table
1322 * Called with the shadow->guest_table_lock
1324 static void __gmap_unshadow_r1t(struct gmap *sg, unsigned long raddr,
1327 unsigned long asce, *r2t;
1331 BUG_ON(!gmap_is_shadow(sg));
1332 asce = (unsigned long) r1t | _ASCE_TYPE_REGION1;
1333 for (i = 0; i < 2048; i++, raddr += 1UL << 53) {
1334 if (r1t[i] & _REGION_ENTRY_INVALID)
1336 r2t = (unsigned long *)(r1t[i] & _REGION_ENTRY_ORIGIN);
1337 __gmap_unshadow_r2t(sg, raddr, r2t);
1338 /* Clear entry and flush translation r1t -> r2t */
1339 gmap_idte_one(asce, raddr);
1340 r1t[i] = _REGION1_ENTRY_EMPTY;
1341 /* Free region 2 table */
1342 page = pfn_to_page(__pa(r2t) >> PAGE_SHIFT);
1343 list_del(&page->lru);
1344 __free_pages(page, 2);
1349 * gmap_unshadow - remove a shadow page table completely
1350 * @sg: pointer to the shadow guest address space structure
1352 * Called with sg->guest_table_lock
1354 static void gmap_unshadow(struct gmap *sg)
1356 unsigned long *table;
1358 BUG_ON(!gmap_is_shadow(sg));
1362 gmap_call_notifier(sg, 0, -1UL);
1364 table = (unsigned long *)(sg->asce & _ASCE_ORIGIN);
1365 switch (sg->asce & _ASCE_TYPE_MASK) {
1366 case _ASCE_TYPE_REGION1:
1367 __gmap_unshadow_r1t(sg, 0, table);
1369 case _ASCE_TYPE_REGION2:
1370 __gmap_unshadow_r2t(sg, 0, table);
1372 case _ASCE_TYPE_REGION3:
1373 __gmap_unshadow_r3t(sg, 0, table);
1375 case _ASCE_TYPE_SEGMENT:
1376 __gmap_unshadow_sgt(sg, 0, table);
1382 * gmap_find_shadow - find a specific asce in the list of shadow tables
1383 * @parent: pointer to the parent gmap
1384 * @asce: ASCE for which the shadow table is created
1386 * Returns the pointer to a gmap if a shadow table with the given asce is
1387 * already available, otherwise NULL
1389 static struct gmap *gmap_find_shadow(struct gmap *parent, unsigned long asce)
1393 list_for_each_entry(sg, &parent->children, list) {
1394 if (sg->orig_asce != asce || sg->removed)
1396 atomic_inc(&sg->ref_count);
1403 * gmap_shadow - create/find a shadow guest address space
1404 * @parent: pointer to the parent gmap
1405 * @asce: ASCE for which the shadow table is created
1407 * The pages of the top level page table referred by the asce parameter
1408 * will be set to read-only and marked in the PGSTEs of the kvm process.
1409 * The shadow table will be removed automatically on any change to the
1410 * PTE mapping for the source table.
1412 * Returns a guest address space structure, NULL if out of memory or if
1413 * anything goes wrong while protecting the top level pages.
1415 struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce)
1417 struct gmap *sg, *new;
1418 unsigned long limit;
1421 BUG_ON(gmap_is_shadow(parent));
1422 spin_lock(&parent->shadow_lock);
1423 sg = gmap_find_shadow(parent, asce);
1424 spin_unlock(&parent->shadow_lock);
1427 /* Create a new shadow gmap */
1428 limit = -1UL >> (33 - (((asce & _ASCE_TYPE_MASK) >> 2) * 11));
1429 new = gmap_alloc(limit);
1432 new->mm = parent->mm;
1433 new->parent = gmap_get(parent);
1434 new->orig_asce = asce;
1435 down_read(&parent->mm->mmap_sem);
1436 rc = gmap_protect_range(parent, asce & _ASCE_ORIGIN,
1437 ((asce & _ASCE_TABLE_LENGTH) + 1) * 4096,
1438 PROT_READ, PGSTE_VSIE_BIT);
1439 up_read(&parent->mm->mmap_sem);
1441 atomic_set(&new->ref_count, 2);
1442 spin_lock(&parent->shadow_lock);
1443 /* Recheck if another CPU created the same shadow */
1444 sg = gmap_find_shadow(parent, asce);
1446 list_add(&new->list, &parent->children);
1450 spin_unlock(&parent->shadow_lock);
1456 EXPORT_SYMBOL_GPL(gmap_shadow);
1459 * gmap_shadow_r2t - create an empty shadow region 2 table
1460 * @sg: pointer to the shadow guest address space structure
1461 * @saddr: faulting address in the shadow gmap
1462 * @r2t: parent gmap address of the region 2 table to get shadowed
1464 * The r2t parameter specifies the address of the source table. The
1465 * four pages of the source table are made read-only in the parent gmap
1466 * address space. A write to the source table area @r2t will automatically
1467 * remove the shadow r2 table and all of its decendents.
1469 * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the
1470 * shadow table structure is incomplete, -ENOMEM if out of memory and
1471 * -EFAULT if an address in the parent gmap could not be resolved.
1473 * Called with sg->mm->mmap_sem in read.
1475 int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t)
1477 unsigned long raddr, origin, offset, len;
1478 unsigned long *s_r2t, *table;
1482 BUG_ON(!gmap_is_shadow(sg));
1483 /* Allocate a shadow region second table */
1484 page = alloc_pages(GFP_KERNEL, 2);
1487 page->index = r2t & _REGION_ENTRY_ORIGIN;
1488 s_r2t = (unsigned long *) page_to_phys(page);
1489 /* Install shadow region second table */
1490 spin_lock(&sg->guest_table_lock);
1491 table = gmap_table_walk(sg, saddr, 4); /* get region-1 pointer */
1493 rc = -EAGAIN; /* Race with unshadow */
1496 if (!(*table & _REGION_ENTRY_INVALID)) {
1497 rc = 0; /* Already established */
1500 crst_table_init(s_r2t, _REGION2_ENTRY_EMPTY);
1501 *table = (unsigned long) s_r2t |
1502 _REGION_ENTRY_LENGTH | _REGION_ENTRY_TYPE_R1;
1503 list_add(&page->lru, &sg->crst_list);
1504 spin_unlock(&sg->guest_table_lock);
1505 /* Make r2t read-only in parent gmap page table */
1506 raddr = (saddr & 0xffe0000000000000UL) | _SHADOW_RMAP_REGION1;
1507 origin = r2t & _REGION_ENTRY_ORIGIN;
1508 offset = ((r2t & _REGION_ENTRY_OFFSET) >> 6) * 4096;
1509 len = ((r2t & _REGION_ENTRY_LENGTH) + 1) * 4096 - offset;
1510 rc = gmap_protect_rmap(sg, raddr, origin + offset, len, PROT_READ);
1512 spin_lock(&sg->guest_table_lock);
1513 gmap_unshadow_r2t(sg, raddr);
1514 spin_unlock(&sg->guest_table_lock);
1518 spin_unlock(&sg->guest_table_lock);
1519 __free_pages(page, 2);
1522 EXPORT_SYMBOL_GPL(gmap_shadow_r2t);
1525 * gmap_shadow_r3t - create a shadow region 3 table
1526 * @sg: pointer to the shadow guest address space structure
1527 * @saddr: faulting address in the shadow gmap
1528 * @r3t: parent gmap address of the region 3 table to get shadowed
1530 * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the
1531 * shadow table structure is incomplete, -ENOMEM if out of memory and
1532 * -EFAULT if an address in the parent gmap could not be resolved.
1534 * Called with sg->mm->mmap_sem in read.
1536 int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t)
1538 unsigned long raddr, origin, offset, len;
1539 unsigned long *s_r3t, *table;
1543 BUG_ON(!gmap_is_shadow(sg));
1544 /* Allocate a shadow region second table */
1545 page = alloc_pages(GFP_KERNEL, 2);
1548 page->index = r3t & _REGION_ENTRY_ORIGIN;
1549 s_r3t = (unsigned long *) page_to_phys(page);
1550 /* Install shadow region second table */
1551 spin_lock(&sg->guest_table_lock);
1552 table = gmap_table_walk(sg, saddr, 3); /* get region-2 pointer */
1554 rc = -EAGAIN; /* Race with unshadow */
1557 if (!(*table & _REGION_ENTRY_INVALID)) {
1558 rc = 0; /* Already established */
1561 crst_table_init(s_r3t, _REGION3_ENTRY_EMPTY);
1562 *table = (unsigned long) s_r3t |
1563 _REGION_ENTRY_LENGTH | _REGION_ENTRY_TYPE_R2;
1564 list_add(&page->lru, &sg->crst_list);
1565 spin_unlock(&sg->guest_table_lock);
1566 /* Make r3t read-only in parent gmap page table */
1567 raddr = (saddr & 0xfffffc0000000000UL) | _SHADOW_RMAP_REGION2;
1568 origin = r3t & _REGION_ENTRY_ORIGIN;
1569 offset = ((r3t & _REGION_ENTRY_OFFSET) >> 6) * 4096;
1570 len = ((r3t & _REGION_ENTRY_LENGTH) + 1) * 4096 - offset;
1571 rc = gmap_protect_rmap(sg, raddr, origin + offset, len, PROT_READ);
1573 spin_lock(&sg->guest_table_lock);
1574 gmap_unshadow_r3t(sg, raddr);
1575 spin_unlock(&sg->guest_table_lock);
1579 spin_unlock(&sg->guest_table_lock);
1580 __free_pages(page, 2);
1583 EXPORT_SYMBOL_GPL(gmap_shadow_r3t);
1586 * gmap_shadow_sgt - create a shadow segment table
1587 * @sg: pointer to the shadow guest address space structure
1588 * @saddr: faulting address in the shadow gmap
1589 * @sgt: parent gmap address of the segment table to get shadowed
1591 * Returns: 0 if successfully shadowed or already shadowed, -EAGAIN if the
1592 * shadow table structure is incomplete, -ENOMEM if out of memory and
1593 * -EFAULT if an address in the parent gmap could not be resolved.
1595 * Called with sg->mm->mmap_sem in read.
1597 int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt)
1599 unsigned long raddr, origin, offset, len;
1600 unsigned long *s_sgt, *table;
1604 BUG_ON(!gmap_is_shadow(sg));
1605 /* Allocate a shadow segment table */
1606 page = alloc_pages(GFP_KERNEL, 2);
1609 page->index = sgt & _REGION_ENTRY_ORIGIN;
1610 s_sgt = (unsigned long *) page_to_phys(page);
1611 /* Install shadow region second table */
1612 spin_lock(&sg->guest_table_lock);
1613 table = gmap_table_walk(sg, saddr, 2); /* get region-3 pointer */
1615 rc = -EAGAIN; /* Race with unshadow */
1618 if (!(*table & _REGION_ENTRY_INVALID)) {
1619 rc = 0; /* Already established */
1622 crst_table_init(s_sgt, _SEGMENT_ENTRY_EMPTY);
1623 *table = (unsigned long) s_sgt |
1624 _REGION_ENTRY_LENGTH | _REGION_ENTRY_TYPE_R3;
1625 list_add(&page->lru, &sg->crst_list);
1626 spin_unlock(&sg->guest_table_lock);
1627 /* Make sgt read-only in parent gmap page table */
1628 raddr = (saddr & 0xffffffff80000000UL) | _SHADOW_RMAP_REGION3;
1629 origin = sgt & _REGION_ENTRY_ORIGIN;
1630 offset = ((sgt & _REGION_ENTRY_OFFSET) >> 6) * 4096;
1631 len = ((sgt & _REGION_ENTRY_LENGTH) + 1) * 4096 - offset;
1632 rc = gmap_protect_rmap(sg, raddr, origin + offset, len, PROT_READ);
1634 spin_lock(&sg->guest_table_lock);
1635 gmap_unshadow_sgt(sg, raddr);
1636 spin_unlock(&sg->guest_table_lock);
1640 spin_unlock(&sg->guest_table_lock);
1641 __free_pages(page, 2);
1644 EXPORT_SYMBOL_GPL(gmap_shadow_sgt);
1647 * gmap_shadow_lookup_pgtable - find a shadow page table
1648 * @sg: pointer to the shadow guest address space structure
1649 * @saddr: the address in the shadow aguest address space
1650 * @pgt: parent gmap address of the page table to get shadowed
1651 * @dat_protection: if the pgtable is marked as protected by dat
1653 * Returns 0 if the shadow page table was found and -EAGAIN if the page
1654 * table was not found.
1656 * Called with sg->mm->mmap_sem in read.
1658 int gmap_shadow_pgt_lookup(struct gmap *sg, unsigned long saddr,
1659 unsigned long *pgt, int *dat_protection)
1661 unsigned long *table;
1665 BUG_ON(!gmap_is_shadow(sg));
1666 spin_lock(&sg->guest_table_lock);
1667 table = gmap_table_walk(sg, saddr, 1); /* get segment pointer */
1668 if (table && !(*table & _SEGMENT_ENTRY_INVALID)) {
1669 /* Shadow page tables are full pages (pte+pgste) */
1670 page = pfn_to_page(*table >> PAGE_SHIFT);
1672 *dat_protection = !!(*table & _SEGMENT_ENTRY_PROTECT);
1677 spin_unlock(&sg->guest_table_lock);
1681 EXPORT_SYMBOL_GPL(gmap_shadow_pgt_lookup);
1684 * gmap_shadow_pgt - instantiate a shadow page table
1685 * @sg: pointer to the shadow guest address space structure
1686 * @saddr: faulting address in the shadow gmap
1687 * @pgt: parent gmap address of the page table to get shadowed
1689 * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the
1690 * shadow table structure is incomplete, -ENOMEM if out of memory,
1691 * -EFAULT if an address in the parent gmap could not be resolved and
1693 * Called with gmap->mm->mmap_sem in read
1695 int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt)
1697 unsigned long raddr, origin;
1698 unsigned long *s_pgt, *table;
1702 BUG_ON(!gmap_is_shadow(sg));
1703 /* Allocate a shadow page table */
1704 page = page_table_alloc_pgste(sg->mm);
1707 page->index = pgt & _SEGMENT_ENTRY_ORIGIN;
1708 s_pgt = (unsigned long *) page_to_phys(page);
1709 /* Install shadow page table */
1710 spin_lock(&sg->guest_table_lock);
1711 table = gmap_table_walk(sg, saddr, 1); /* get segment pointer */
1713 rc = -EAGAIN; /* Race with unshadow */
1716 if (!(*table & _SEGMENT_ENTRY_INVALID)) {
1717 rc = 0; /* Already established */
1720 *table = (unsigned long) s_pgt | _SEGMENT_ENTRY |
1721 (pgt & _SEGMENT_ENTRY_PROTECT);
1722 list_add(&page->lru, &sg->pt_list);
1723 spin_unlock(&sg->guest_table_lock);
1724 /* Make pgt read-only in parent gmap page table (not the pgste) */
1725 raddr = (saddr & 0xfffffffffff00000UL) | _SHADOW_RMAP_SEGMENT;
1726 origin = pgt & _SEGMENT_ENTRY_ORIGIN & PAGE_MASK;
1727 rc = gmap_protect_rmap(sg, raddr, origin, PAGE_SIZE, PROT_READ);
1729 spin_lock(&sg->guest_table_lock);
1730 gmap_unshadow_pgt(sg, raddr);
1731 spin_unlock(&sg->guest_table_lock);
1735 spin_unlock(&sg->guest_table_lock);
1736 page_table_free_pgste(page);
1740 EXPORT_SYMBOL_GPL(gmap_shadow_pgt);
1743 * gmap_shadow_page - create a shadow page mapping
1744 * @sg: pointer to the shadow guest address space structure
1745 * @saddr: faulting address in the shadow gmap
1746 * @paddr: parent gmap address to get mapped at @saddr
1747 * @write: =1 map r/w, =0 map r/o
1749 * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the
1750 * shadow table structure is incomplete, -ENOMEM if out of memory and
1751 * -EFAULT if an address in the parent gmap could not be resolved.
1753 * Called with sg->mm->mmap_sem in read.
1755 int gmap_shadow_page(struct gmap *sg, unsigned long saddr,
1756 unsigned long paddr, int write)
1758 struct gmap *parent;
1759 struct gmap_rmap *rmap;
1760 unsigned long vmaddr;
1762 pte_t *sptep, *tptep;
1765 BUG_ON(!gmap_is_shadow(sg));
1766 parent = sg->parent;
1768 rmap = kzalloc(sizeof(*rmap), GFP_KERNEL);
1771 rmap->raddr = (saddr & PAGE_MASK) | _SHADOW_RMAP_PGTABLE;
1774 vmaddr = __gmap_translate(parent, paddr);
1775 if (IS_ERR_VALUE(vmaddr)) {
1779 rc = radix_tree_preload(GFP_KERNEL);
1783 sptep = gmap_pte_op_walk(parent, paddr, &ptl);
1785 spin_lock(&sg->guest_table_lock);
1786 /* Get page table pointer */
1787 tptep = (pte_t *) gmap_table_walk(sg, saddr, 0);
1789 spin_unlock(&sg->guest_table_lock);
1790 gmap_pte_op_end(ptl);
1791 radix_tree_preload_end();
1794 rc = ptep_shadow_pte(sg->mm, saddr,
1795 sptep, tptep, write);
1797 /* Success and a new mapping */
1798 gmap_insert_rmap(sg, vmaddr, rmap);
1802 gmap_pte_op_end(ptl);
1803 spin_unlock(&sg->guest_table_lock);
1805 radix_tree_preload_end();
1808 rc = gmap_pte_op_fixup(parent, paddr, vmaddr);
1815 EXPORT_SYMBOL_GPL(gmap_shadow_page);
1818 * gmap_shadow_notify - handle notifications for shadow gmap
1820 * Called with sg->parent->shadow_lock.
1822 static void gmap_shadow_notify(struct gmap *sg, unsigned long vmaddr,
1823 unsigned long offset, pte_t *pte)
1825 struct gmap_rmap *rmap, *rnext, *head;
1826 unsigned long gaddr, start, end, bits, raddr;
1827 unsigned long *table;
1829 BUG_ON(!gmap_is_shadow(sg));
1830 spin_lock(&sg->parent->guest_table_lock);
1831 table = radix_tree_lookup(&sg->parent->host_to_guest,
1832 vmaddr >> PMD_SHIFT);
1833 gaddr = table ? __gmap_segment_gaddr(table) + offset : 0;
1834 spin_unlock(&sg->parent->guest_table_lock);
1838 spin_lock(&sg->guest_table_lock);
1840 spin_unlock(&sg->guest_table_lock);
1843 /* Check for top level table */
1844 start = sg->orig_asce & _ASCE_ORIGIN;
1845 end = start + ((sg->orig_asce & _ASCE_TABLE_LENGTH) + 1) * 4096;
1846 if (gaddr >= start && gaddr < end) {
1847 /* The complete shadow table has to go */
1849 spin_unlock(&sg->guest_table_lock);
1850 list_del(&sg->list);
1854 /* Remove the page table tree from on specific entry */
1855 head = radix_tree_delete(&sg->host_to_rmap, vmaddr >> 12);
1856 gmap_for_each_rmap_safe(rmap, rnext, head) {
1857 bits = rmap->raddr & _SHADOW_RMAP_MASK;
1858 raddr = rmap->raddr ^ bits;
1860 case _SHADOW_RMAP_REGION1:
1861 gmap_unshadow_r2t(sg, raddr);
1863 case _SHADOW_RMAP_REGION2:
1864 gmap_unshadow_r3t(sg, raddr);
1866 case _SHADOW_RMAP_REGION3:
1867 gmap_unshadow_sgt(sg, raddr);
1869 case _SHADOW_RMAP_SEGMENT:
1870 gmap_unshadow_pgt(sg, raddr);
1872 case _SHADOW_RMAP_PGTABLE:
1873 gmap_unshadow_page(sg, raddr);
1878 spin_unlock(&sg->guest_table_lock);
1882 * ptep_notify - call all invalidation callbacks for a specific pte.
1883 * @mm: pointer to the process mm_struct
1884 * @addr: virtual address in the process address space
1885 * @pte: pointer to the page table entry
1886 * @bits: bits from the pgste that caused the notify call
1888 * This function is assumed to be called with the page table lock held
1889 * for the pte to notify.
1891 void ptep_notify(struct mm_struct *mm, unsigned long vmaddr,
1892 pte_t *pte, unsigned long bits)
1894 unsigned long offset, gaddr;
1895 unsigned long *table;
1896 struct gmap *gmap, *sg, *next;
1898 offset = ((unsigned long) pte) & (255 * sizeof(pte_t));
1899 offset = offset * (4096 / sizeof(pte_t));
1901 list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) {
1902 if (!list_empty(&gmap->children) && (bits & PGSTE_VSIE_BIT)) {
1903 spin_lock(&gmap->shadow_lock);
1904 list_for_each_entry_safe(sg, next,
1905 &gmap->children, list)
1906 gmap_shadow_notify(sg, vmaddr, offset, pte);
1907 spin_unlock(&gmap->shadow_lock);
1909 if (!(bits & PGSTE_IN_BIT))
1911 spin_lock(&gmap->guest_table_lock);
1912 table = radix_tree_lookup(&gmap->host_to_guest,
1913 vmaddr >> PMD_SHIFT);
1915 gaddr = __gmap_segment_gaddr(table) + offset;
1916 spin_unlock(&gmap->guest_table_lock);
1918 gmap_call_notifier(gmap, gaddr, gaddr + PAGE_SIZE - 1);
1922 EXPORT_SYMBOL_GPL(ptep_notify);
1924 static inline void thp_split_mm(struct mm_struct *mm)
1926 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1927 struct vm_area_struct *vma;
1930 for (vma = mm->mmap; vma != NULL; vma = vma->vm_next) {
1931 for (addr = vma->vm_start;
1934 follow_page(vma, addr, FOLL_SPLIT);
1935 vma->vm_flags &= ~VM_HUGEPAGE;
1936 vma->vm_flags |= VM_NOHUGEPAGE;
1938 mm->def_flags |= VM_NOHUGEPAGE;
1943 * switch on pgstes for its userspace process (for kvm)
1945 int s390_enable_sie(void)
1947 struct mm_struct *mm = current->mm;
1949 /* Do we have pgstes? if yes, we are done */
1950 if (mm_has_pgste(mm))
1952 /* Fail if the page tables are 2K */
1953 if (!mm_alloc_pgste(mm))
1955 down_write(&mm->mmap_sem);
1956 mm->context.has_pgste = 1;
1957 /* split thp mappings and disable thp for future mappings */
1959 up_write(&mm->mmap_sem);
1962 EXPORT_SYMBOL_GPL(s390_enable_sie);
1965 * Enable storage key handling from now on and initialize the storage
1966 * keys with the default key.
1968 static int __s390_enable_skey(pte_t *pte, unsigned long addr,
1969 unsigned long next, struct mm_walk *walk)
1972 * Remove all zero page mappings,
1973 * after establishing a policy to forbid zero page mappings
1974 * following faults for that page will get fresh anonymous pages
1976 if (is_zero_pfn(pte_pfn(*pte)))
1977 ptep_xchg_direct(walk->mm, addr, pte, __pte(_PAGE_INVALID));
1978 /* Clear storage key */
1979 ptep_zap_key(walk->mm, addr, pte);
1983 int s390_enable_skey(void)
1985 struct mm_walk walk = { .pte_entry = __s390_enable_skey };
1986 struct mm_struct *mm = current->mm;
1987 struct vm_area_struct *vma;
1990 down_write(&mm->mmap_sem);
1991 if (mm_use_skey(mm))
1994 mm->context.use_skey = 1;
1995 for (vma = mm->mmap; vma; vma = vma->vm_next) {
1996 if (ksm_madvise(vma, vma->vm_start, vma->vm_end,
1997 MADV_UNMERGEABLE, &vma->vm_flags)) {
1998 mm->context.use_skey = 0;
2003 mm->def_flags &= ~VM_MERGEABLE;
2006 walk_page_range(0, TASK_SIZE, &walk);
2009 up_write(&mm->mmap_sem);
2012 EXPORT_SYMBOL_GPL(s390_enable_skey);
2015 * Reset CMMA state, make all pages stable again.
2017 static int __s390_reset_cmma(pte_t *pte, unsigned long addr,
2018 unsigned long next, struct mm_walk *walk)
2020 ptep_zap_unused(walk->mm, addr, pte, 1);
2024 void s390_reset_cmma(struct mm_struct *mm)
2026 struct mm_walk walk = { .pte_entry = __s390_reset_cmma };
2028 down_write(&mm->mmap_sem);
2030 walk_page_range(0, TASK_SIZE, &walk);
2031 up_write(&mm->mmap_sem);
2033 EXPORT_SYMBOL_GPL(s390_reset_cmma);