+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0
-/*
- * KVM guest address space mapping code
- *
- * Copyright IBM Corp. 2007, 2020
- * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
- * David Hildenbrand <david@redhat.com>
- * Janosch Frank <frankja@linux.vnet.ibm.com>
- */
-
-#include <linux/cpufeature.h>
-#include <linux/export.h>
-#include <linux/kernel.h>
-#include <linux/pagewalk.h>
-#include <linux/swap.h>
-#include <linux/smp.h>
-#include <linux/spinlock.h>
-#include <linux/slab.h>
-#include <linux/swapops.h>
-#include <linux/ksm.h>
-#include <linux/mman.h>
-#include <linux/pgtable.h>
-#include <asm/page-states.h>
-#include <asm/pgalloc.h>
-#include <asm/machine.h>
-#include <asm/gmap_helpers.h>
-#include <asm/gmap.h>
-#include <asm/page.h>
-
-/*
- * The address is saved in a radix tree directly; NULL would be ambiguous,
- * since 0 is a valid address, and NULL is returned when nothing was found.
- * The lower bits are ignored by all users of the macro, so it can be used
- * to distinguish a valid address 0 from a NULL.
- */
-#define VALID_GADDR_FLAG 1
-#define IS_GADDR_VALID(gaddr) ((gaddr) & VALID_GADDR_FLAG)
-#define MAKE_VALID_GADDR(gaddr) (((gaddr) & HPAGE_MASK) | VALID_GADDR_FLAG)
-
-#define GMAP_SHADOW_FAKE_TABLE 1ULL
-
-static struct page *gmap_alloc_crst(void)
-{
- struct page *page;
-
- page = alloc_pages(GFP_KERNEL_ACCOUNT, CRST_ALLOC_ORDER);
- if (!page)
- return NULL;
- __arch_set_page_dat(page_to_virt(page), 1UL << CRST_ALLOC_ORDER);
- return page;
-}
-
-/**
- * gmap_alloc - allocate and initialize a guest address space
- * @limit: maximum address of the gmap address space
- *
- * Returns a guest address space structure.
- */
-struct gmap *gmap_alloc(unsigned long limit)
-{
- struct gmap *gmap;
- struct page *page;
- unsigned long *table;
- unsigned long etype, atype;
-
- if (limit < _REGION3_SIZE) {
- limit = _REGION3_SIZE - 1;
- atype = _ASCE_TYPE_SEGMENT;
- etype = _SEGMENT_ENTRY_EMPTY;
- } else if (limit < _REGION2_SIZE) {
- limit = _REGION2_SIZE - 1;
- atype = _ASCE_TYPE_REGION3;
- etype = _REGION3_ENTRY_EMPTY;
- } else if (limit < _REGION1_SIZE) {
- limit = _REGION1_SIZE - 1;
- atype = _ASCE_TYPE_REGION2;
- etype = _REGION2_ENTRY_EMPTY;
- } else {
- limit = -1UL;
- atype = _ASCE_TYPE_REGION1;
- etype = _REGION1_ENTRY_EMPTY;
- }
- gmap = kzalloc(sizeof(struct gmap), GFP_KERNEL_ACCOUNT);
- if (!gmap)
- goto out;
- INIT_LIST_HEAD(&gmap->children);
- INIT_RADIX_TREE(&gmap->guest_to_host, GFP_KERNEL_ACCOUNT);
- INIT_RADIX_TREE(&gmap->host_to_guest, GFP_ATOMIC | __GFP_ACCOUNT);
- INIT_RADIX_TREE(&gmap->host_to_rmap, GFP_ATOMIC | __GFP_ACCOUNT);
- spin_lock_init(&gmap->guest_table_lock);
- spin_lock_init(&gmap->shadow_lock);
- refcount_set(&gmap->ref_count, 1);
- page = gmap_alloc_crst();
- if (!page)
- goto out_free;
- table = page_to_virt(page);
- crst_table_init(table, etype);
- gmap->table = table;
- gmap->asce = atype | _ASCE_TABLE_LENGTH |
- _ASCE_USER_BITS | __pa(table);
- gmap->asce_end = limit;
- return gmap;
-
-out_free:
- kfree(gmap);
-out:
- return NULL;
-}
-EXPORT_SYMBOL_GPL(gmap_alloc);
-
-/**
- * gmap_create - create a guest address space
- * @mm: pointer to the parent mm_struct
- * @limit: maximum size of the gmap address space
- *
- * Returns a guest address space structure.
- */
-struct gmap *gmap_create(struct mm_struct *mm, unsigned long limit)
-{
- struct gmap *gmap;
- unsigned long gmap_asce;
-
- gmap = gmap_alloc(limit);
- if (!gmap)
- return NULL;
- gmap->mm = mm;
- spin_lock(&mm->context.lock);
- list_add_rcu(&gmap->list, &mm->context.gmap_list);
- if (list_is_singular(&mm->context.gmap_list))
- gmap_asce = gmap->asce;
- else
- gmap_asce = -1UL;
- WRITE_ONCE(mm->context.gmap_asce, gmap_asce);
- spin_unlock(&mm->context.lock);
- return gmap;
-}
-EXPORT_SYMBOL_GPL(gmap_create);
-
-static void gmap_flush_tlb(struct gmap *gmap)
-{
- __tlb_flush_idte(gmap->asce);
-}
-
-static void gmap_radix_tree_free(struct radix_tree_root *root)
-{
- struct radix_tree_iter iter;
- unsigned long indices[16];
- unsigned long index;
- void __rcu **slot;
- int i, nr;
-
- /* A radix tree is freed by deleting all of its entries */
- index = 0;
- do {
- nr = 0;
- radix_tree_for_each_slot(slot, root, &iter, index) {
- indices[nr] = iter.index;
- if (++nr == 16)
- break;
- }
- for (i = 0; i < nr; i++) {
- index = indices[i];
- radix_tree_delete(root, index);
- }
- } while (nr > 0);
-}
-
-static void gmap_rmap_radix_tree_free(struct radix_tree_root *root)
-{
- struct gmap_rmap *rmap, *rnext, *head;
- struct radix_tree_iter iter;
- unsigned long indices[16];
- unsigned long index;
- void __rcu **slot;
- int i, nr;
-
- /* A radix tree is freed by deleting all of its entries */
- index = 0;
- do {
- nr = 0;
- radix_tree_for_each_slot(slot, root, &iter, index) {
- indices[nr] = iter.index;
- if (++nr == 16)
- break;
- }
- for (i = 0; i < nr; i++) {
- index = indices[i];
- head = radix_tree_delete(root, index);
- gmap_for_each_rmap_safe(rmap, rnext, head)
- kfree(rmap);
- }
- } while (nr > 0);
-}
-
-static void gmap_free_crst(unsigned long *table, bool free_ptes)
-{
- bool is_segment = (table[0] & _SEGMENT_ENTRY_TYPE_MASK) == 0;
- int i;
-
- if (is_segment) {
- if (!free_ptes)
- goto out;
- for (i = 0; i < _CRST_ENTRIES; i++)
- if (!(table[i] & _SEGMENT_ENTRY_INVALID))
- page_table_free_pgste(page_ptdesc(phys_to_page(table[i])));
- } else {
- for (i = 0; i < _CRST_ENTRIES; i++)
- if (!(table[i] & _REGION_ENTRY_INVALID))
- gmap_free_crst(__va(table[i] & PAGE_MASK), free_ptes);
- }
-
-out:
- free_pages((unsigned long)table, CRST_ALLOC_ORDER);
-}
-
-/**
- * gmap_free - free a guest address space
- * @gmap: pointer to the guest address space structure
- *
- * No locks required. There are no references to this gmap anymore.
- */
-void gmap_free(struct gmap *gmap)
-{
- /* Flush tlb of all gmaps (if not already done for shadows) */
- if (!(gmap_is_shadow(gmap) && gmap->removed))
- gmap_flush_tlb(gmap);
- /* Free all segment & region tables. */
- gmap_free_crst(gmap->table, gmap_is_shadow(gmap));
-
- gmap_radix_tree_free(&gmap->guest_to_host);
- gmap_radix_tree_free(&gmap->host_to_guest);
-
- /* Free additional data for a shadow gmap */
- if (gmap_is_shadow(gmap)) {
- gmap_rmap_radix_tree_free(&gmap->host_to_rmap);
- /* Release reference to the parent */
- gmap_put(gmap->parent);
- }
-
- kfree(gmap);
-}
-EXPORT_SYMBOL_GPL(gmap_free);
-
-/**
- * gmap_get - increase reference counter for guest address space
- * @gmap: pointer to the guest address space structure
- *
- * Returns the gmap pointer
- */
-struct gmap *gmap_get(struct gmap *gmap)
-{
- refcount_inc(&gmap->ref_count);
- return gmap;
-}
-EXPORT_SYMBOL_GPL(gmap_get);
-
-/**
- * gmap_put - decrease reference counter for guest address space
- * @gmap: pointer to the guest address space structure
- *
- * If the reference counter reaches zero the guest address space is freed.
- */
-void gmap_put(struct gmap *gmap)
-{
- if (refcount_dec_and_test(&gmap->ref_count))
- gmap_free(gmap);
-}
-EXPORT_SYMBOL_GPL(gmap_put);
-
-/**
- * gmap_remove - remove a guest address space but do not free it yet
- * @gmap: pointer to the guest address space structure
- */
-void gmap_remove(struct gmap *gmap)
-{
- struct gmap *sg, *next;
- unsigned long gmap_asce;
-
- /* Remove all shadow gmaps linked to this gmap */
- if (!list_empty(&gmap->children)) {
- spin_lock(&gmap->shadow_lock);
- list_for_each_entry_safe(sg, next, &gmap->children, list) {
- list_del(&sg->list);
- gmap_put(sg);
- }
- spin_unlock(&gmap->shadow_lock);
- }
- /* Remove gmap from the pre-mm list */
- spin_lock(&gmap->mm->context.lock);
- list_del_rcu(&gmap->list);
- if (list_empty(&gmap->mm->context.gmap_list))
- gmap_asce = 0;
- else if (list_is_singular(&gmap->mm->context.gmap_list))
- gmap_asce = list_first_entry(&gmap->mm->context.gmap_list,
- struct gmap, list)->asce;
- else
- gmap_asce = -1UL;
- WRITE_ONCE(gmap->mm->context.gmap_asce, gmap_asce);
- spin_unlock(&gmap->mm->context.lock);
- synchronize_rcu();
- /* Put reference */
- gmap_put(gmap);
-}
-EXPORT_SYMBOL_GPL(gmap_remove);
-
-/*
- * gmap_alloc_table is assumed to be called with mmap_lock held
- */
-static int gmap_alloc_table(struct gmap *gmap, unsigned long *table,
- unsigned long init, unsigned long gaddr)
-{
- struct page *page;
- unsigned long *new;
-
- /* since we dont free the gmap table until gmap_free we can unlock */
- page = gmap_alloc_crst();
- if (!page)
- return -ENOMEM;
- new = page_to_virt(page);
- crst_table_init(new, init);
- spin_lock(&gmap->guest_table_lock);
- if (*table & _REGION_ENTRY_INVALID) {
- *table = __pa(new) | _REGION_ENTRY_LENGTH |
- (*table & _REGION_ENTRY_TYPE_MASK);
- page = NULL;
- }
- spin_unlock(&gmap->guest_table_lock);
- if (page)
- __free_pages(page, CRST_ALLOC_ORDER);
- return 0;
-}
-
-static unsigned long host_to_guest_lookup(struct gmap *gmap, unsigned long vmaddr)
-{
- return (unsigned long)radix_tree_lookup(&gmap->host_to_guest, vmaddr >> PMD_SHIFT);
-}
-
-static unsigned long host_to_guest_delete(struct gmap *gmap, unsigned long vmaddr)
-{
- return (unsigned long)radix_tree_delete(&gmap->host_to_guest, vmaddr >> PMD_SHIFT);
-}
-
-static pmd_t *host_to_guest_pmd_delete(struct gmap *gmap, unsigned long vmaddr,
- unsigned long *gaddr)
-{
- *gaddr = host_to_guest_delete(gmap, vmaddr);
- if (IS_GADDR_VALID(*gaddr))
- return (pmd_t *)gmap_table_walk(gmap, *gaddr, 1);
- return NULL;
-}
-
-/**
- * __gmap_unlink_by_vmaddr - unlink a single segment via a host address
- * @gmap: pointer to the guest address space structure
- * @vmaddr: address in the host process address space
- *
- * Returns 1 if a TLB flush is required
- */
-static int __gmap_unlink_by_vmaddr(struct gmap *gmap, unsigned long vmaddr)
-{
- unsigned long gaddr;
- int flush = 0;
- pmd_t *pmdp;
-
- BUG_ON(gmap_is_shadow(gmap));
- spin_lock(&gmap->guest_table_lock);
-
- pmdp = host_to_guest_pmd_delete(gmap, vmaddr, &gaddr);
- if (pmdp) {
- flush = (pmd_val(*pmdp) != _SEGMENT_ENTRY_EMPTY);
- *pmdp = __pmd(_SEGMENT_ENTRY_EMPTY);
- }
-
- spin_unlock(&gmap->guest_table_lock);
- return flush;
-}
-
-/**
- * __gmap_unmap_by_gaddr - unmap a single segment via a guest address
- * @gmap: pointer to the guest address space structure
- * @gaddr: address in the guest address space
- *
- * Returns 1 if a TLB flush is required
- */
-static int __gmap_unmap_by_gaddr(struct gmap *gmap, unsigned long gaddr)
-{
- unsigned long vmaddr;
-
- vmaddr = (unsigned long) radix_tree_delete(&gmap->guest_to_host,
- gaddr >> PMD_SHIFT);
- return vmaddr ? __gmap_unlink_by_vmaddr(gmap, vmaddr) : 0;
-}
-
-/**
- * gmap_unmap_segment - unmap segment from the guest address space
- * @gmap: pointer to the guest address space structure
- * @to: address in the guest address space
- * @len: length of the memory area to unmap
- *
- * Returns 0 if the unmap succeeded, -EINVAL if not.
- */
-int gmap_unmap_segment(struct gmap *gmap, unsigned long to, unsigned long len)
-{
- unsigned long off;
- int flush;
-
- BUG_ON(gmap_is_shadow(gmap));
- if ((to | len) & (PMD_SIZE - 1))
- return -EINVAL;
- if (len == 0 || to + len < to)
- return -EINVAL;
-
- flush = 0;
- mmap_write_lock(gmap->mm);
- for (off = 0; off < len; off += PMD_SIZE)
- flush |= __gmap_unmap_by_gaddr(gmap, to + off);
- mmap_write_unlock(gmap->mm);
- if (flush)
- gmap_flush_tlb(gmap);
- return 0;
-}
-EXPORT_SYMBOL_GPL(gmap_unmap_segment);
-
-/**
- * gmap_map_segment - map a segment to the guest address space
- * @gmap: pointer to the guest address space structure
- * @from: source address in the parent address space
- * @to: target address in the guest address space
- * @len: length of the memory area to map
- *
- * Returns 0 if the mmap succeeded, -EINVAL or -ENOMEM if not.
- */
-int gmap_map_segment(struct gmap *gmap, unsigned long from,
- unsigned long to, unsigned long len)
-{
- unsigned long off;
- int flush;
-
- BUG_ON(gmap_is_shadow(gmap));
- if ((from | to | len) & (PMD_SIZE - 1))
- return -EINVAL;
- if (len == 0 || from + len < from || to + len < to ||
- from + len - 1 > TASK_SIZE_MAX || to + len - 1 > gmap->asce_end)
- return -EINVAL;
-
- flush = 0;
- mmap_write_lock(gmap->mm);
- for (off = 0; off < len; off += PMD_SIZE) {
- /* Remove old translation */
- flush |= __gmap_unmap_by_gaddr(gmap, to + off);
- /* Store new translation */
- if (radix_tree_insert(&gmap->guest_to_host,
- (to + off) >> PMD_SHIFT,
- (void *) from + off))
- break;
- }
- mmap_write_unlock(gmap->mm);
- if (flush)
- gmap_flush_tlb(gmap);
- if (off >= len)
- return 0;
- gmap_unmap_segment(gmap, to, len);
- return -ENOMEM;
-}
-EXPORT_SYMBOL_GPL(gmap_map_segment);
-
-/**
- * __gmap_translate - translate a guest address to a user space address
- * @gmap: pointer to guest mapping meta data structure
- * @gaddr: guest address
- *
- * Returns user space address which corresponds to the guest address or
- * -EFAULT if no such mapping exists.
- * This function does not establish potentially missing page table entries.
- * The mmap_lock of the mm that belongs to the address space must be held
- * when this function gets called.
- *
- * Note: Can also be called for shadow gmaps.
- */
-unsigned long __gmap_translate(struct gmap *gmap, unsigned long gaddr)
-{
- unsigned long vmaddr;
-
- vmaddr = (unsigned long)
- radix_tree_lookup(&gmap->guest_to_host, gaddr >> PMD_SHIFT);
- /* Note: guest_to_host is empty for a shadow gmap */
- return vmaddr ? (vmaddr | (gaddr & ~PMD_MASK)) : -EFAULT;
-}
-EXPORT_SYMBOL_GPL(__gmap_translate);
-
-/**
- * gmap_unlink - disconnect a page table from the gmap shadow tables
- * @mm: pointer to the parent mm_struct
- * @table: pointer to the host page table
- * @vmaddr: vm address associated with the host page table
- */
-void gmap_unlink(struct mm_struct *mm, unsigned long *table,
- unsigned long vmaddr)
-{
- struct gmap *gmap;
- int flush;
-
- rcu_read_lock();
- list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) {
- flush = __gmap_unlink_by_vmaddr(gmap, vmaddr);
- if (flush)
- gmap_flush_tlb(gmap);
- }
- rcu_read_unlock();
-}
-
-static void gmap_pmdp_xchg(struct gmap *gmap, pmd_t *old, pmd_t new,
- unsigned long gaddr);
-
-/**
- * __gmap_link - set up shadow page tables to connect a host to a guest address
- * @gmap: pointer to guest mapping meta data structure
- * @gaddr: guest address
- * @vmaddr: vm address
- *
- * Returns 0 on success, -ENOMEM for out of memory conditions, and -EFAULT
- * if the vm address is already mapped to a different guest segment.
- * The mmap_lock of the mm that belongs to the address space must be held
- * when this function gets called.
- */
-int __gmap_link(struct gmap *gmap, unsigned long gaddr, unsigned long vmaddr)
-{
- struct mm_struct *mm;
- unsigned long *table;
- spinlock_t *ptl;
- pgd_t *pgd;
- p4d_t *p4d;
- pud_t *pud;
- pmd_t *pmd;
- u64 unprot;
- int rc;
-
- BUG_ON(gmap_is_shadow(gmap));
- /* Create higher level tables in the gmap page table */
- table = gmap->table;
- if ((gmap->asce & _ASCE_TYPE_MASK) >= _ASCE_TYPE_REGION1) {
- table += (gaddr & _REGION1_INDEX) >> _REGION1_SHIFT;
- if ((*table & _REGION_ENTRY_INVALID) &&
- gmap_alloc_table(gmap, table, _REGION2_ENTRY_EMPTY,
- gaddr & _REGION1_MASK))
- return -ENOMEM;
- table = __va(*table & _REGION_ENTRY_ORIGIN);
- }
- if ((gmap->asce & _ASCE_TYPE_MASK) >= _ASCE_TYPE_REGION2) {
- table += (gaddr & _REGION2_INDEX) >> _REGION2_SHIFT;
- if ((*table & _REGION_ENTRY_INVALID) &&
- gmap_alloc_table(gmap, table, _REGION3_ENTRY_EMPTY,
- gaddr & _REGION2_MASK))
- return -ENOMEM;
- table = __va(*table & _REGION_ENTRY_ORIGIN);
- }
- if ((gmap->asce & _ASCE_TYPE_MASK) >= _ASCE_TYPE_REGION3) {
- table += (gaddr & _REGION3_INDEX) >> _REGION3_SHIFT;
- if ((*table & _REGION_ENTRY_INVALID) &&
- gmap_alloc_table(gmap, table, _SEGMENT_ENTRY_EMPTY,
- gaddr & _REGION3_MASK))
- return -ENOMEM;
- table = __va(*table & _REGION_ENTRY_ORIGIN);
- }
- table += (gaddr & _SEGMENT_INDEX) >> _SEGMENT_SHIFT;
- /* Walk the parent mm page table */
- mm = gmap->mm;
- pgd = pgd_offset(mm, vmaddr);
- VM_BUG_ON(pgd_none(*pgd));
- p4d = p4d_offset(pgd, vmaddr);
- VM_BUG_ON(p4d_none(*p4d));
- pud = pud_offset(p4d, vmaddr);
- VM_BUG_ON(pud_none(*pud));
- /* large puds cannot yet be handled */
- if (pud_leaf(*pud))
- return -EFAULT;
- pmd = pmd_offset(pud, vmaddr);
- VM_BUG_ON(pmd_none(*pmd));
- /* Are we allowed to use huge pages? */
- if (pmd_leaf(*pmd) && !gmap->mm->context.allow_gmap_hpage_1m)
- return -EFAULT;
- /* Link gmap segment table entry location to page table. */
- rc = radix_tree_preload(GFP_KERNEL_ACCOUNT);
- if (rc)
- return rc;
- ptl = pmd_lock(mm, pmd);
- spin_lock(&gmap->guest_table_lock);
- if (*table == _SEGMENT_ENTRY_EMPTY) {
- rc = radix_tree_insert(&gmap->host_to_guest,
- vmaddr >> PMD_SHIFT,
- (void *)MAKE_VALID_GADDR(gaddr));
- if (!rc) {
- if (pmd_leaf(*pmd)) {
- *table = (pmd_val(*pmd) &
- _SEGMENT_ENTRY_HARDWARE_BITS_LARGE)
- | _SEGMENT_ENTRY_GMAP_UC
- | _SEGMENT_ENTRY;
- } else
- *table = (pmd_val(*pmd) &
- _SEGMENT_ENTRY_HARDWARE_BITS)
- | _SEGMENT_ENTRY;
- }
- } else if (*table & _SEGMENT_ENTRY_PROTECT &&
- !(pmd_val(*pmd) & _SEGMENT_ENTRY_PROTECT)) {
- unprot = (u64)*table;
- unprot &= ~_SEGMENT_ENTRY_PROTECT;
- unprot |= _SEGMENT_ENTRY_GMAP_UC;
- gmap_pmdp_xchg(gmap, (pmd_t *)table, __pmd(unprot), gaddr);
- }
- spin_unlock(&gmap->guest_table_lock);
- spin_unlock(ptl);
- radix_tree_preload_end();
- return rc;
-}
-EXPORT_SYMBOL(__gmap_link);
-
-/*
- * this function is assumed to be called with mmap_lock held
- */
-void __gmap_zap(struct gmap *gmap, unsigned long gaddr)
-{
- unsigned long vmaddr;
-
- mmap_assert_locked(gmap->mm);
-
- /* Find the vm address for the guest address */
- vmaddr = (unsigned long) radix_tree_lookup(&gmap->guest_to_host,
- gaddr >> PMD_SHIFT);
- if (vmaddr) {
- vmaddr |= gaddr & ~PMD_MASK;
- gmap_helper_zap_one_page(gmap->mm, vmaddr);
- }
-}
-EXPORT_SYMBOL_GPL(__gmap_zap);
-
-static LIST_HEAD(gmap_notifier_list);
-static DEFINE_SPINLOCK(gmap_notifier_lock);
-
-/**
- * gmap_register_pte_notifier - register a pte invalidation callback
- * @nb: pointer to the gmap notifier block
- */
-void gmap_register_pte_notifier(struct gmap_notifier *nb)
-{
- spin_lock(&gmap_notifier_lock);
- list_add_rcu(&nb->list, &gmap_notifier_list);
- spin_unlock(&gmap_notifier_lock);
-}
-EXPORT_SYMBOL_GPL(gmap_register_pte_notifier);
-
-/**
- * gmap_unregister_pte_notifier - remove a pte invalidation callback
- * @nb: pointer to the gmap notifier block
- */
-void gmap_unregister_pte_notifier(struct gmap_notifier *nb)
-{
- spin_lock(&gmap_notifier_lock);
- list_del_rcu(&nb->list);
- spin_unlock(&gmap_notifier_lock);
- synchronize_rcu();
-}
-EXPORT_SYMBOL_GPL(gmap_unregister_pte_notifier);
-
-/**
- * gmap_call_notifier - call all registered invalidation callbacks
- * @gmap: pointer to guest mapping meta data structure
- * @start: start virtual address in the guest address space
- * @end: end virtual address in the guest address space
- */
-static void gmap_call_notifier(struct gmap *gmap, unsigned long start,
- unsigned long end)
-{
- struct gmap_notifier *nb;
-
- list_for_each_entry(nb, &gmap_notifier_list, list)
- nb->notifier_call(gmap, start, end);
-}
-
-/**
- * gmap_table_walk - walk the gmap page tables
- * @gmap: pointer to guest mapping meta data structure
- * @gaddr: virtual address in the guest address space
- * @level: page table level to stop at
- *
- * Returns a table entry pointer for the given guest address and @level
- * @level=0 : returns a pointer to a page table table entry (or NULL)
- * @level=1 : returns a pointer to a segment table entry (or NULL)
- * @level=2 : returns a pointer to a region-3 table entry (or NULL)
- * @level=3 : returns a pointer to a region-2 table entry (or NULL)
- * @level=4 : returns a pointer to a region-1 table entry (or NULL)
- *
- * Returns NULL if the gmap page tables could not be walked to the
- * requested level.
- *
- * Note: Can also be called for shadow gmaps.
- */
-unsigned long *gmap_table_walk(struct gmap *gmap, unsigned long gaddr, int level)
-{
- const int asce_type = gmap->asce & _ASCE_TYPE_MASK;
- unsigned long *table = gmap->table;
-
- if (gmap_is_shadow(gmap) && gmap->removed)
- return NULL;
-
- if (WARN_ON_ONCE(level > (asce_type >> 2) + 1))
- return NULL;
-
- if (asce_type != _ASCE_TYPE_REGION1 &&
- gaddr & (-1UL << (31 + (asce_type >> 2) * 11)))
- return NULL;
-
- switch (asce_type) {
- case _ASCE_TYPE_REGION1:
- table += (gaddr & _REGION1_INDEX) >> _REGION1_SHIFT;
- if (level == 4)
- break;
- if (*table & _REGION_ENTRY_INVALID)
- return NULL;
- table = __va(*table & _REGION_ENTRY_ORIGIN);
- fallthrough;
- case _ASCE_TYPE_REGION2:
- table += (gaddr & _REGION2_INDEX) >> _REGION2_SHIFT;
- if (level == 3)
- break;
- if (*table & _REGION_ENTRY_INVALID)
- return NULL;
- table = __va(*table & _REGION_ENTRY_ORIGIN);
- fallthrough;
- case _ASCE_TYPE_REGION3:
- table += (gaddr & _REGION3_INDEX) >> _REGION3_SHIFT;
- if (level == 2)
- break;
- if (*table & _REGION_ENTRY_INVALID)
- return NULL;
- table = __va(*table & _REGION_ENTRY_ORIGIN);
- fallthrough;
- case _ASCE_TYPE_SEGMENT:
- table += (gaddr & _SEGMENT_INDEX) >> _SEGMENT_SHIFT;
- if (level == 1)
- break;
- if (*table & _REGION_ENTRY_INVALID)
- return NULL;
- table = __va(*table & _SEGMENT_ENTRY_ORIGIN);
- table += (gaddr & _PAGE_INDEX) >> PAGE_SHIFT;
- }
- return table;
-}
-EXPORT_SYMBOL(gmap_table_walk);
-
-/**
- * gmap_pte_op_walk - walk the gmap page table, get the page table lock
- * and return the pte pointer
- * @gmap: pointer to guest mapping meta data structure
- * @gaddr: virtual address in the guest address space
- * @ptl: pointer to the spinlock pointer
- *
- * Returns a pointer to the locked pte for a guest address, or NULL
- */
-static pte_t *gmap_pte_op_walk(struct gmap *gmap, unsigned long gaddr,
- spinlock_t **ptl)
-{
- unsigned long *table;
-
- BUG_ON(gmap_is_shadow(gmap));
- /* Walk the gmap page table, lock and get pte pointer */
- table = gmap_table_walk(gmap, gaddr, 1); /* get segment pointer */
- if (!table || *table & _SEGMENT_ENTRY_INVALID)
- return NULL;
- return pte_alloc_map_lock(gmap->mm, (pmd_t *) table, gaddr, ptl);
-}
-
-/**
- * gmap_pte_op_fixup - force a page in and connect the gmap page table
- * @gmap: pointer to guest mapping meta data structure
- * @gaddr: virtual address in the guest address space
- * @vmaddr: address in the host process address space
- * @prot: indicates access rights: PROT_NONE, PROT_READ or PROT_WRITE
- *
- * Returns 0 if the caller can retry __gmap_translate (might fail again),
- * -ENOMEM if out of memory and -EFAULT if anything goes wrong while fixing
- * up or connecting the gmap page table.
- */
-static int gmap_pte_op_fixup(struct gmap *gmap, unsigned long gaddr,
- unsigned long vmaddr, int prot)
-{
- struct mm_struct *mm = gmap->mm;
- unsigned int fault_flags;
- bool unlocked = false;
-
- BUG_ON(gmap_is_shadow(gmap));
- fault_flags = (prot == PROT_WRITE) ? FAULT_FLAG_WRITE : 0;
- if (fixup_user_fault(mm, vmaddr, fault_flags, &unlocked))
- return -EFAULT;
- if (unlocked)
- /* lost mmap_lock, caller has to retry __gmap_translate */
- return 0;
- /* Connect the page tables */
- return __gmap_link(gmap, gaddr, vmaddr);
-}
-
-/**
- * gmap_pte_op_end - release the page table lock
- * @ptep: pointer to the locked pte
- * @ptl: pointer to the page table spinlock
- */
-static void gmap_pte_op_end(pte_t *ptep, spinlock_t *ptl)
-{
- pte_unmap_unlock(ptep, ptl);
-}
-
-/**
- * gmap_pmd_op_walk - walk the gmap tables, get the guest table lock
- * and return the pmd pointer
- * @gmap: pointer to guest mapping meta data structure
- * @gaddr: virtual address in the guest address space
- *
- * Returns a pointer to the pmd for a guest address, or NULL
- */
-static inline pmd_t *gmap_pmd_op_walk(struct gmap *gmap, unsigned long gaddr)
-{
- pmd_t *pmdp;
-
- BUG_ON(gmap_is_shadow(gmap));
- pmdp = (pmd_t *) gmap_table_walk(gmap, gaddr, 1);
- if (!pmdp)
- return NULL;
-
- /* without huge pages, there is no need to take the table lock */
- if (!gmap->mm->context.allow_gmap_hpage_1m)
- return pmd_none(*pmdp) ? NULL : pmdp;
-
- spin_lock(&gmap->guest_table_lock);
- if (pmd_none(*pmdp)) {
- spin_unlock(&gmap->guest_table_lock);
- return NULL;
- }
-
- /* 4k page table entries are locked via the pte (pte_alloc_map_lock). */
- if (!pmd_leaf(*pmdp))
- spin_unlock(&gmap->guest_table_lock);
- return pmdp;
-}
-
-/**
- * gmap_pmd_op_end - release the guest_table_lock if needed
- * @gmap: pointer to the guest mapping meta data structure
- * @pmdp: pointer to the pmd
- */
-static inline void gmap_pmd_op_end(struct gmap *gmap, pmd_t *pmdp)
-{
- if (pmd_leaf(*pmdp))
- spin_unlock(&gmap->guest_table_lock);
-}
-
-/*
- * gmap_protect_pmd - remove access rights to memory and set pmd notification bits
- * @pmdp: pointer to the pmd to be protected
- * @prot: indicates access rights: PROT_NONE, PROT_READ or PROT_WRITE
- * @bits: notification bits to set
- *
- * Returns:
- * 0 if successfully protected
- * -EAGAIN if a fixup is needed
- * -EINVAL if unsupported notifier bits have been specified
- *
- * Expected to be called with sg->mm->mmap_lock in read and
- * guest_table_lock held.
- */
-static int gmap_protect_pmd(struct gmap *gmap, unsigned long gaddr,
- pmd_t *pmdp, int prot, unsigned long bits)
-{
- int pmd_i = pmd_val(*pmdp) & _SEGMENT_ENTRY_INVALID;
- int pmd_p = pmd_val(*pmdp) & _SEGMENT_ENTRY_PROTECT;
- pmd_t new = *pmdp;
-
- /* Fixup needed */
- if ((pmd_i && (prot != PROT_NONE)) || (pmd_p && (prot == PROT_WRITE)))
- return -EAGAIN;
-
- if (prot == PROT_NONE && !pmd_i) {
- new = set_pmd_bit(new, __pgprot(_SEGMENT_ENTRY_INVALID));
- gmap_pmdp_xchg(gmap, pmdp, new, gaddr);
- }
-
- if (prot == PROT_READ && !pmd_p) {
- new = clear_pmd_bit(new, __pgprot(_SEGMENT_ENTRY_INVALID));
- new = set_pmd_bit(new, __pgprot(_SEGMENT_ENTRY_PROTECT));
- gmap_pmdp_xchg(gmap, pmdp, new, gaddr);
- }
-
- if (bits & GMAP_NOTIFY_MPROT)
- set_pmd(pmdp, set_pmd_bit(*pmdp, __pgprot(_SEGMENT_ENTRY_GMAP_IN)));
-
- /* Shadow GMAP protection needs split PMDs */
- if (bits & GMAP_NOTIFY_SHADOW)
- return -EINVAL;
-
- return 0;
-}
-
-/*
- * gmap_protect_pte - remove access rights to memory and set pgste bits
- * @gmap: pointer to guest mapping meta data structure
- * @gaddr: virtual address in the guest address space
- * @pmdp: pointer to the pmd associated with the pte
- * @prot: indicates access rights: PROT_NONE, PROT_READ or PROT_WRITE
- * @bits: notification bits to set
- *
- * Returns 0 if successfully protected, -ENOMEM if out of memory and
- * -EAGAIN if a fixup is needed.
- *
- * Expected to be called with sg->mm->mmap_lock in read
- */
-static int gmap_protect_pte(struct gmap *gmap, unsigned long gaddr,
- pmd_t *pmdp, int prot, unsigned long bits)
-{
- int rc;
- pte_t *ptep;
- spinlock_t *ptl;
- unsigned long pbits = 0;
-
- if (pmd_val(*pmdp) & _SEGMENT_ENTRY_INVALID)
- return -EAGAIN;
-
- ptep = pte_alloc_map_lock(gmap->mm, pmdp, gaddr, &ptl);
- if (!ptep)
- return -ENOMEM;
-
- pbits |= (bits & GMAP_NOTIFY_MPROT) ? PGSTE_IN_BIT : 0;
- pbits |= (bits & GMAP_NOTIFY_SHADOW) ? PGSTE_VSIE_BIT : 0;
- /* Protect and unlock. */
- rc = ptep_force_prot(gmap->mm, gaddr, ptep, prot, pbits);
- gmap_pte_op_end(ptep, ptl);
- return rc;
-}
-
-/*
- * gmap_protect_range - remove access rights to memory and set pgste bits
- * @gmap: pointer to guest mapping meta data structure
- * @gaddr: virtual address in the guest address space
- * @len: size of area
- * @prot: indicates access rights: PROT_NONE, PROT_READ or PROT_WRITE
- * @bits: pgste notification bits to set
- *
- * Returns:
- * PAGE_SIZE if a small page was successfully protected;
- * HPAGE_SIZE if a large page was successfully protected;
- * -ENOMEM if out of memory;
- * -EFAULT if gaddr is invalid (or mapping for shadows is missing);
- * -EAGAIN if the guest mapping is missing and should be fixed by the caller.
- *
- * Context: Called with sg->mm->mmap_lock in read.
- */
-int gmap_protect_one(struct gmap *gmap, unsigned long gaddr, int prot, unsigned long bits)
-{
- pmd_t *pmdp;
- int rc = 0;
-
- BUG_ON(gmap_is_shadow(gmap));
-
- pmdp = gmap_pmd_op_walk(gmap, gaddr);
- if (!pmdp)
- return -EAGAIN;
-
- if (!pmd_leaf(*pmdp)) {
- rc = gmap_protect_pte(gmap, gaddr, pmdp, prot, bits);
- if (!rc)
- rc = PAGE_SIZE;
- } else {
- rc = gmap_protect_pmd(gmap, gaddr, pmdp, prot, bits);
- if (!rc)
- rc = HPAGE_SIZE;
- }
- gmap_pmd_op_end(gmap, pmdp);
-
- return rc;
-}
-EXPORT_SYMBOL_GPL(gmap_protect_one);
-
-/**
- * gmap_read_table - get an unsigned long value from a guest page table using
- * absolute addressing, without marking the page referenced.
- * @gmap: pointer to guest mapping meta data structure
- * @gaddr: virtual address in the guest address space
- * @val: pointer to the unsigned long value to return
- *
- * Returns 0 if the value was read, -ENOMEM if out of memory and -EFAULT
- * if reading using the virtual address failed. -EINVAL if called on a gmap
- * shadow.
- *
- * Called with gmap->mm->mmap_lock in read.
- */
-int gmap_read_table(struct gmap *gmap, unsigned long gaddr, unsigned long *val)
-{
- unsigned long address, vmaddr;
- spinlock_t *ptl;
- pte_t *ptep, pte;
- int rc;
-
- if (gmap_is_shadow(gmap))
- return -EINVAL;
-
- while (1) {
- rc = -EAGAIN;
- ptep = gmap_pte_op_walk(gmap, gaddr, &ptl);
- if (ptep) {
- pte = *ptep;
- if (pte_present(pte) && (pte_val(pte) & _PAGE_READ)) {
- address = pte_val(pte) & PAGE_MASK;
- address += gaddr & ~PAGE_MASK;
- *val = *(unsigned long *)__va(address);
- set_pte(ptep, set_pte_bit(*ptep, __pgprot(_PAGE_YOUNG)));
- /* Do *NOT* clear the _PAGE_INVALID bit! */
- rc = 0;
- }
- gmap_pte_op_end(ptep, ptl);
- }
- if (!rc)
- break;
- vmaddr = __gmap_translate(gmap, gaddr);
- if (IS_ERR_VALUE(vmaddr)) {
- rc = vmaddr;
- break;
- }
- rc = gmap_pte_op_fixup(gmap, gaddr, vmaddr, PROT_READ);
- if (rc)
- break;
- }
- return rc;
-}
-EXPORT_SYMBOL_GPL(gmap_read_table);
-
-/**
- * gmap_insert_rmap - add a rmap to the host_to_rmap radix tree
- * @sg: pointer to the shadow guest address space structure
- * @vmaddr: vm address associated with the rmap
- * @rmap: pointer to the rmap structure
- *
- * Called with the sg->guest_table_lock
- */
-static inline void gmap_insert_rmap(struct gmap *sg, unsigned long vmaddr,
- struct gmap_rmap *rmap)
-{
- struct gmap_rmap *temp;
- void __rcu **slot;
-
- BUG_ON(!gmap_is_shadow(sg));
- slot = radix_tree_lookup_slot(&sg->host_to_rmap, vmaddr >> PAGE_SHIFT);
- if (slot) {
- rmap->next = radix_tree_deref_slot_protected(slot,
- &sg->guest_table_lock);
- for (temp = rmap->next; temp; temp = temp->next) {
- if (temp->raddr == rmap->raddr) {
- kfree(rmap);
- return;
- }
- }
- radix_tree_replace_slot(&sg->host_to_rmap, slot, rmap);
- } else {
- rmap->next = NULL;
- radix_tree_insert(&sg->host_to_rmap, vmaddr >> PAGE_SHIFT,
- rmap);
- }
-}
-
-/**
- * gmap_protect_rmap - restrict access rights to memory (RO) and create an rmap
- * @sg: pointer to the shadow guest address space structure
- * @raddr: rmap address in the shadow gmap
- * @paddr: address in the parent guest address space
- * @len: length of the memory area to protect
- *
- * Returns 0 if successfully protected and the rmap was created, -ENOMEM
- * if out of memory and -EFAULT if paddr is invalid.
- */
-static int gmap_protect_rmap(struct gmap *sg, unsigned long raddr,
- unsigned long paddr, unsigned long len)
-{
- struct gmap *parent;
- struct gmap_rmap *rmap;
- unsigned long vmaddr;
- spinlock_t *ptl;
- pte_t *ptep;
- int rc;
-
- BUG_ON(!gmap_is_shadow(sg));
- parent = sg->parent;
- while (len) {
- vmaddr = __gmap_translate(parent, paddr);
- if (IS_ERR_VALUE(vmaddr))
- return vmaddr;
- rmap = kzalloc(sizeof(*rmap), GFP_KERNEL_ACCOUNT);
- if (!rmap)
- return -ENOMEM;
- rmap->raddr = raddr;
- rc = radix_tree_preload(GFP_KERNEL_ACCOUNT);
- if (rc) {
- kfree(rmap);
- return rc;
- }
- rc = -EAGAIN;
- ptep = gmap_pte_op_walk(parent, paddr, &ptl);
- if (ptep) {
- spin_lock(&sg->guest_table_lock);
- rc = ptep_force_prot(parent->mm, paddr, ptep, PROT_READ,
- PGSTE_VSIE_BIT);
- if (!rc)
- gmap_insert_rmap(sg, vmaddr, rmap);
- spin_unlock(&sg->guest_table_lock);
- gmap_pte_op_end(ptep, ptl);
- }
- radix_tree_preload_end();
- if (rc) {
- kfree(rmap);
- rc = gmap_pte_op_fixup(parent, paddr, vmaddr, PROT_READ);
- if (rc)
- return rc;
- continue;
- }
- paddr += PAGE_SIZE;
- len -= PAGE_SIZE;
- }
- return 0;
-}
-
-#define _SHADOW_RMAP_MASK 0x7
-#define _SHADOW_RMAP_REGION1 0x5
-#define _SHADOW_RMAP_REGION2 0x4
-#define _SHADOW_RMAP_REGION3 0x3
-#define _SHADOW_RMAP_SEGMENT 0x2
-#define _SHADOW_RMAP_PGTABLE 0x1
-
-/**
- * gmap_idte_one - invalidate a single region or segment table entry
- * @asce: region or segment table *origin* + table-type bits
- * @vaddr: virtual address to identify the table entry to flush
- *
- * The invalid bit of a single region or segment table entry is set
- * and the associated TLB entries depending on the entry are flushed.
- * The table-type of the @asce identifies the portion of the @vaddr
- * that is used as the invalidation index.
- */
-static inline void gmap_idte_one(unsigned long asce, unsigned long vaddr)
-{
- asm volatile(
- " idte %0,0,%1"
- : : "a" (asce), "a" (vaddr) : "cc", "memory");
-}
-
-/**
- * gmap_unshadow_page - remove a page from a shadow page table
- * @sg: pointer to the shadow guest address space structure
- * @raddr: rmap address in the shadow guest address space
- *
- * Called with the sg->guest_table_lock
- */
-static void gmap_unshadow_page(struct gmap *sg, unsigned long raddr)
-{
- unsigned long *table;
-
- BUG_ON(!gmap_is_shadow(sg));
- table = gmap_table_walk(sg, raddr, 0); /* get page table pointer */
- if (!table || *table & _PAGE_INVALID)
- return;
- gmap_call_notifier(sg, raddr, raddr + PAGE_SIZE - 1);
- ptep_unshadow_pte(sg->mm, raddr, (pte_t *) table);
-}
-
-/**
- * __gmap_unshadow_pgt - remove all entries from a shadow page table
- * @sg: pointer to the shadow guest address space structure
- * @raddr: rmap address in the shadow guest address space
- * @pgt: pointer to the start of a shadow page table
- *
- * Called with the sg->guest_table_lock
- */
-static void __gmap_unshadow_pgt(struct gmap *sg, unsigned long raddr,
- unsigned long *pgt)
-{
- int i;
-
- BUG_ON(!gmap_is_shadow(sg));
- for (i = 0; i < _PAGE_ENTRIES; i++, raddr += PAGE_SIZE)
- pgt[i] = _PAGE_INVALID;
-}
-
-/**
- * gmap_unshadow_pgt - remove a shadow page table from a segment entry
- * @sg: pointer to the shadow guest address space structure
- * @raddr: address in the shadow guest address space
- *
- * Called with the sg->guest_table_lock
- */
-static void gmap_unshadow_pgt(struct gmap *sg, unsigned long raddr)
-{
- unsigned long *ste;
- phys_addr_t sto, pgt;
- struct ptdesc *ptdesc;
-
- BUG_ON(!gmap_is_shadow(sg));
- ste = gmap_table_walk(sg, raddr, 1); /* get segment pointer */
- if (!ste || !(*ste & _SEGMENT_ENTRY_ORIGIN))
- return;
- gmap_call_notifier(sg, raddr, raddr + _SEGMENT_SIZE - 1);
- sto = __pa(ste - ((raddr & _SEGMENT_INDEX) >> _SEGMENT_SHIFT));
- gmap_idte_one(sto | _ASCE_TYPE_SEGMENT, raddr);
- pgt = *ste & _SEGMENT_ENTRY_ORIGIN;
- *ste = _SEGMENT_ENTRY_EMPTY;
- __gmap_unshadow_pgt(sg, raddr, __va(pgt));
- /* Free page table */
- ptdesc = page_ptdesc(phys_to_page(pgt));
- page_table_free_pgste(ptdesc);
-}
-
-/**
- * __gmap_unshadow_sgt - remove all entries from a shadow segment table
- * @sg: pointer to the shadow guest address space structure
- * @raddr: rmap address in the shadow guest address space
- * @sgt: pointer to the start of a shadow segment table
- *
- * Called with the sg->guest_table_lock
- */
-static void __gmap_unshadow_sgt(struct gmap *sg, unsigned long raddr,
- unsigned long *sgt)
-{
- struct ptdesc *ptdesc;
- phys_addr_t pgt;
- int i;
-
- BUG_ON(!gmap_is_shadow(sg));
- for (i = 0; i < _CRST_ENTRIES; i++, raddr += _SEGMENT_SIZE) {
- if (!(sgt[i] & _SEGMENT_ENTRY_ORIGIN))
- continue;
- pgt = sgt[i] & _REGION_ENTRY_ORIGIN;
- sgt[i] = _SEGMENT_ENTRY_EMPTY;
- __gmap_unshadow_pgt(sg, raddr, __va(pgt));
- /* Free page table */
- ptdesc = page_ptdesc(phys_to_page(pgt));
- page_table_free_pgste(ptdesc);
- }
-}
-
-/**
- * gmap_unshadow_sgt - remove a shadow segment table from a region-3 entry
- * @sg: pointer to the shadow guest address space structure
- * @raddr: rmap address in the shadow guest address space
- *
- * Called with the shadow->guest_table_lock
- */
-static void gmap_unshadow_sgt(struct gmap *sg, unsigned long raddr)
-{
- unsigned long r3o, *r3e;
- phys_addr_t sgt;
- struct page *page;
-
- BUG_ON(!gmap_is_shadow(sg));
- r3e = gmap_table_walk(sg, raddr, 2); /* get region-3 pointer */
- if (!r3e || !(*r3e & _REGION_ENTRY_ORIGIN))
- return;
- gmap_call_notifier(sg, raddr, raddr + _REGION3_SIZE - 1);
- r3o = (unsigned long) (r3e - ((raddr & _REGION3_INDEX) >> _REGION3_SHIFT));
- gmap_idte_one(__pa(r3o) | _ASCE_TYPE_REGION3, raddr);
- sgt = *r3e & _REGION_ENTRY_ORIGIN;
- *r3e = _REGION3_ENTRY_EMPTY;
- __gmap_unshadow_sgt(sg, raddr, __va(sgt));
- /* Free segment table */
- page = phys_to_page(sgt);
- __free_pages(page, CRST_ALLOC_ORDER);
-}
-
-/**
- * __gmap_unshadow_r3t - remove all entries from a shadow region-3 table
- * @sg: pointer to the shadow guest address space structure
- * @raddr: address in the shadow guest address space
- * @r3t: pointer to the start of a shadow region-3 table
- *
- * Called with the sg->guest_table_lock
- */
-static void __gmap_unshadow_r3t(struct gmap *sg, unsigned long raddr,
- unsigned long *r3t)
-{
- struct page *page;
- phys_addr_t sgt;
- int i;
-
- BUG_ON(!gmap_is_shadow(sg));
- for (i = 0; i < _CRST_ENTRIES; i++, raddr += _REGION3_SIZE) {
- if (!(r3t[i] & _REGION_ENTRY_ORIGIN))
- continue;
- sgt = r3t[i] & _REGION_ENTRY_ORIGIN;
- r3t[i] = _REGION3_ENTRY_EMPTY;
- __gmap_unshadow_sgt(sg, raddr, __va(sgt));
- /* Free segment table */
- page = phys_to_page(sgt);
- __free_pages(page, CRST_ALLOC_ORDER);
- }
-}
-
-/**
- * gmap_unshadow_r3t - remove a shadow region-3 table from a region-2 entry
- * @sg: pointer to the shadow guest address space structure
- * @raddr: rmap address in the shadow guest address space
- *
- * Called with the sg->guest_table_lock
- */
-static void gmap_unshadow_r3t(struct gmap *sg, unsigned long raddr)
-{
- unsigned long r2o, *r2e;
- phys_addr_t r3t;
- struct page *page;
-
- BUG_ON(!gmap_is_shadow(sg));
- r2e = gmap_table_walk(sg, raddr, 3); /* get region-2 pointer */
- if (!r2e || !(*r2e & _REGION_ENTRY_ORIGIN))
- return;
- gmap_call_notifier(sg, raddr, raddr + _REGION2_SIZE - 1);
- r2o = (unsigned long) (r2e - ((raddr & _REGION2_INDEX) >> _REGION2_SHIFT));
- gmap_idte_one(__pa(r2o) | _ASCE_TYPE_REGION2, raddr);
- r3t = *r2e & _REGION_ENTRY_ORIGIN;
- *r2e = _REGION2_ENTRY_EMPTY;
- __gmap_unshadow_r3t(sg, raddr, __va(r3t));
- /* Free region 3 table */
- page = phys_to_page(r3t);
- __free_pages(page, CRST_ALLOC_ORDER);
-}
-
-/**
- * __gmap_unshadow_r2t - remove all entries from a shadow region-2 table
- * @sg: pointer to the shadow guest address space structure
- * @raddr: rmap address in the shadow guest address space
- * @r2t: pointer to the start of a shadow region-2 table
- *
- * Called with the sg->guest_table_lock
- */
-static void __gmap_unshadow_r2t(struct gmap *sg, unsigned long raddr,
- unsigned long *r2t)
-{
- phys_addr_t r3t;
- struct page *page;
- int i;
-
- BUG_ON(!gmap_is_shadow(sg));
- for (i = 0; i < _CRST_ENTRIES; i++, raddr += _REGION2_SIZE) {
- if (!(r2t[i] & _REGION_ENTRY_ORIGIN))
- continue;
- r3t = r2t[i] & _REGION_ENTRY_ORIGIN;
- r2t[i] = _REGION2_ENTRY_EMPTY;
- __gmap_unshadow_r3t(sg, raddr, __va(r3t));
- /* Free region 3 table */
- page = phys_to_page(r3t);
- __free_pages(page, CRST_ALLOC_ORDER);
- }
-}
-
-/**
- * gmap_unshadow_r2t - remove a shadow region-2 table from a region-1 entry
- * @sg: pointer to the shadow guest address space structure
- * @raddr: rmap address in the shadow guest address space
- *
- * Called with the sg->guest_table_lock
- */
-static void gmap_unshadow_r2t(struct gmap *sg, unsigned long raddr)
-{
- unsigned long r1o, *r1e;
- struct page *page;
- phys_addr_t r2t;
-
- BUG_ON(!gmap_is_shadow(sg));
- r1e = gmap_table_walk(sg, raddr, 4); /* get region-1 pointer */
- if (!r1e || !(*r1e & _REGION_ENTRY_ORIGIN))
- return;
- gmap_call_notifier(sg, raddr, raddr + _REGION1_SIZE - 1);
- r1o = (unsigned long) (r1e - ((raddr & _REGION1_INDEX) >> _REGION1_SHIFT));
- gmap_idte_one(__pa(r1o) | _ASCE_TYPE_REGION1, raddr);
- r2t = *r1e & _REGION_ENTRY_ORIGIN;
- *r1e = _REGION1_ENTRY_EMPTY;
- __gmap_unshadow_r2t(sg, raddr, __va(r2t));
- /* Free region 2 table */
- page = phys_to_page(r2t);
- __free_pages(page, CRST_ALLOC_ORDER);
-}
-
-/**
- * __gmap_unshadow_r1t - remove all entries from a shadow region-1 table
- * @sg: pointer to the shadow guest address space structure
- * @raddr: rmap address in the shadow guest address space
- * @r1t: pointer to the start of a shadow region-1 table
- *
- * Called with the shadow->guest_table_lock
- */
-static void __gmap_unshadow_r1t(struct gmap *sg, unsigned long raddr,
- unsigned long *r1t)
-{
- unsigned long asce;
- struct page *page;
- phys_addr_t r2t;
- int i;
-
- BUG_ON(!gmap_is_shadow(sg));
- asce = __pa(r1t) | _ASCE_TYPE_REGION1;
- for (i = 0; i < _CRST_ENTRIES; i++, raddr += _REGION1_SIZE) {
- if (!(r1t[i] & _REGION_ENTRY_ORIGIN))
- continue;
- r2t = r1t[i] & _REGION_ENTRY_ORIGIN;
- __gmap_unshadow_r2t(sg, raddr, __va(r2t));
- /* Clear entry and flush translation r1t -> r2t */
- gmap_idte_one(asce, raddr);
- r1t[i] = _REGION1_ENTRY_EMPTY;
- /* Free region 2 table */
- page = phys_to_page(r2t);
- __free_pages(page, CRST_ALLOC_ORDER);
- }
-}
-
-/**
- * gmap_unshadow - remove a shadow page table completely
- * @sg: pointer to the shadow guest address space structure
- *
- * Called with sg->guest_table_lock
- */
-void gmap_unshadow(struct gmap *sg)
-{
- unsigned long *table;
-
- BUG_ON(!gmap_is_shadow(sg));
- if (sg->removed)
- return;
- sg->removed = 1;
- gmap_call_notifier(sg, 0, -1UL);
- gmap_flush_tlb(sg);
- table = __va(sg->asce & _ASCE_ORIGIN);
- switch (sg->asce & _ASCE_TYPE_MASK) {
- case _ASCE_TYPE_REGION1:
- __gmap_unshadow_r1t(sg, 0, table);
- break;
- case _ASCE_TYPE_REGION2:
- __gmap_unshadow_r2t(sg, 0, table);
- break;
- case _ASCE_TYPE_REGION3:
- __gmap_unshadow_r3t(sg, 0, table);
- break;
- case _ASCE_TYPE_SEGMENT:
- __gmap_unshadow_sgt(sg, 0, table);
- break;
- }
-}
-EXPORT_SYMBOL(gmap_unshadow);
-
-/**
- * gmap_shadow_r2t - create an empty shadow region 2 table
- * @sg: pointer to the shadow guest address space structure
- * @saddr: faulting address in the shadow gmap
- * @r2t: parent gmap address of the region 2 table to get shadowed
- * @fake: r2t references contiguous guest memory block, not a r2t
- *
- * The r2t parameter specifies the address of the source table. The
- * four pages of the source table are made read-only in the parent gmap
- * address space. A write to the source table area @r2t will automatically
- * remove the shadow r2 table and all of its descendants.
- *
- * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the
- * shadow table structure is incomplete, -ENOMEM if out of memory and
- * -EFAULT if an address in the parent gmap could not be resolved.
- *
- * Called with sg->mm->mmap_lock in read.
- */
-int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t,
- int fake)
-{
- unsigned long raddr, origin, offset, len;
- unsigned long *table;
- phys_addr_t s_r2t;
- struct page *page;
- int rc;
-
- BUG_ON(!gmap_is_shadow(sg));
- /* Allocate a shadow region second table */
- page = gmap_alloc_crst();
- if (!page)
- return -ENOMEM;
- s_r2t = page_to_phys(page);
- /* Install shadow region second table */
- spin_lock(&sg->guest_table_lock);
- table = gmap_table_walk(sg, saddr, 4); /* get region-1 pointer */
- if (!table) {
- rc = -EAGAIN; /* Race with unshadow */
- goto out_free;
- }
- if (!(*table & _REGION_ENTRY_INVALID)) {
- rc = 0; /* Already established */
- goto out_free;
- } else if (*table & _REGION_ENTRY_ORIGIN) {
- rc = -EAGAIN; /* Race with shadow */
- goto out_free;
- }
- crst_table_init(__va(s_r2t), _REGION2_ENTRY_EMPTY);
- /* mark as invalid as long as the parent table is not protected */
- *table = s_r2t | _REGION_ENTRY_LENGTH |
- _REGION_ENTRY_TYPE_R1 | _REGION_ENTRY_INVALID;
- if (sg->edat_level >= 1)
- *table |= (r2t & _REGION_ENTRY_PROTECT);
- if (fake) {
- /* nothing to protect for fake tables */
- *table &= ~_REGION_ENTRY_INVALID;
- spin_unlock(&sg->guest_table_lock);
- return 0;
- }
- spin_unlock(&sg->guest_table_lock);
- /* Make r2t read-only in parent gmap page table */
- raddr = (saddr & _REGION1_MASK) | _SHADOW_RMAP_REGION1;
- origin = r2t & _REGION_ENTRY_ORIGIN;
- offset = ((r2t & _REGION_ENTRY_OFFSET) >> 6) * PAGE_SIZE;
- len = ((r2t & _REGION_ENTRY_LENGTH) + 1) * PAGE_SIZE - offset;
- rc = gmap_protect_rmap(sg, raddr, origin + offset, len);
- spin_lock(&sg->guest_table_lock);
- if (!rc) {
- table = gmap_table_walk(sg, saddr, 4);
- if (!table || (*table & _REGION_ENTRY_ORIGIN) != s_r2t)
- rc = -EAGAIN; /* Race with unshadow */
- else
- *table &= ~_REGION_ENTRY_INVALID;
- } else {
- gmap_unshadow_r2t(sg, raddr);
- }
- spin_unlock(&sg->guest_table_lock);
- return rc;
-out_free:
- spin_unlock(&sg->guest_table_lock);
- __free_pages(page, CRST_ALLOC_ORDER);
- return rc;
-}
-EXPORT_SYMBOL_GPL(gmap_shadow_r2t);
-
-/**
- * gmap_shadow_r3t - create a shadow region 3 table
- * @sg: pointer to the shadow guest address space structure
- * @saddr: faulting address in the shadow gmap
- * @r3t: parent gmap address of the region 3 table to get shadowed
- * @fake: r3t references contiguous guest memory block, not a r3t
- *
- * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the
- * shadow table structure is incomplete, -ENOMEM if out of memory and
- * -EFAULT if an address in the parent gmap could not be resolved.
- *
- * Called with sg->mm->mmap_lock in read.
- */
-int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t,
- int fake)
-{
- unsigned long raddr, origin, offset, len;
- unsigned long *table;
- phys_addr_t s_r3t;
- struct page *page;
- int rc;
-
- BUG_ON(!gmap_is_shadow(sg));
- /* Allocate a shadow region second table */
- page = gmap_alloc_crst();
- if (!page)
- return -ENOMEM;
- s_r3t = page_to_phys(page);
- /* Install shadow region second table */
- spin_lock(&sg->guest_table_lock);
- table = gmap_table_walk(sg, saddr, 3); /* get region-2 pointer */
- if (!table) {
- rc = -EAGAIN; /* Race with unshadow */
- goto out_free;
- }
- if (!(*table & _REGION_ENTRY_INVALID)) {
- rc = 0; /* Already established */
- goto out_free;
- } else if (*table & _REGION_ENTRY_ORIGIN) {
- rc = -EAGAIN; /* Race with shadow */
- goto out_free;
- }
- crst_table_init(__va(s_r3t), _REGION3_ENTRY_EMPTY);
- /* mark as invalid as long as the parent table is not protected */
- *table = s_r3t | _REGION_ENTRY_LENGTH |
- _REGION_ENTRY_TYPE_R2 | _REGION_ENTRY_INVALID;
- if (sg->edat_level >= 1)
- *table |= (r3t & _REGION_ENTRY_PROTECT);
- if (fake) {
- /* nothing to protect for fake tables */
- *table &= ~_REGION_ENTRY_INVALID;
- spin_unlock(&sg->guest_table_lock);
- return 0;
- }
- spin_unlock(&sg->guest_table_lock);
- /* Make r3t read-only in parent gmap page table */
- raddr = (saddr & _REGION2_MASK) | _SHADOW_RMAP_REGION2;
- origin = r3t & _REGION_ENTRY_ORIGIN;
- offset = ((r3t & _REGION_ENTRY_OFFSET) >> 6) * PAGE_SIZE;
- len = ((r3t & _REGION_ENTRY_LENGTH) + 1) * PAGE_SIZE - offset;
- rc = gmap_protect_rmap(sg, raddr, origin + offset, len);
- spin_lock(&sg->guest_table_lock);
- if (!rc) {
- table = gmap_table_walk(sg, saddr, 3);
- if (!table || (*table & _REGION_ENTRY_ORIGIN) != s_r3t)
- rc = -EAGAIN; /* Race with unshadow */
- else
- *table &= ~_REGION_ENTRY_INVALID;
- } else {
- gmap_unshadow_r3t(sg, raddr);
- }
- spin_unlock(&sg->guest_table_lock);
- return rc;
-out_free:
- spin_unlock(&sg->guest_table_lock);
- __free_pages(page, CRST_ALLOC_ORDER);
- return rc;
-}
-EXPORT_SYMBOL_GPL(gmap_shadow_r3t);
-
-/**
- * gmap_shadow_sgt - create a shadow segment table
- * @sg: pointer to the shadow guest address space structure
- * @saddr: faulting address in the shadow gmap
- * @sgt: parent gmap address of the segment table to get shadowed
- * @fake: sgt references contiguous guest memory block, not a sgt
- *
- * Returns: 0 if successfully shadowed or already shadowed, -EAGAIN if the
- * shadow table structure is incomplete, -ENOMEM if out of memory and
- * -EFAULT if an address in the parent gmap could not be resolved.
- *
- * Called with sg->mm->mmap_lock in read.
- */
-int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt,
- int fake)
-{
- unsigned long raddr, origin, offset, len;
- unsigned long *table;
- phys_addr_t s_sgt;
- struct page *page;
- int rc;
-
- BUG_ON(!gmap_is_shadow(sg) || (sgt & _REGION3_ENTRY_LARGE));
- /* Allocate a shadow segment table */
- page = gmap_alloc_crst();
- if (!page)
- return -ENOMEM;
- s_sgt = page_to_phys(page);
- /* Install shadow region second table */
- spin_lock(&sg->guest_table_lock);
- table = gmap_table_walk(sg, saddr, 2); /* get region-3 pointer */
- if (!table) {
- rc = -EAGAIN; /* Race with unshadow */
- goto out_free;
- }
- if (!(*table & _REGION_ENTRY_INVALID)) {
- rc = 0; /* Already established */
- goto out_free;
- } else if (*table & _REGION_ENTRY_ORIGIN) {
- rc = -EAGAIN; /* Race with shadow */
- goto out_free;
- }
- crst_table_init(__va(s_sgt), _SEGMENT_ENTRY_EMPTY);
- /* mark as invalid as long as the parent table is not protected */
- *table = s_sgt | _REGION_ENTRY_LENGTH |
- _REGION_ENTRY_TYPE_R3 | _REGION_ENTRY_INVALID;
- if (sg->edat_level >= 1)
- *table |= sgt & _REGION_ENTRY_PROTECT;
- if (fake) {
- /* nothing to protect for fake tables */
- *table &= ~_REGION_ENTRY_INVALID;
- spin_unlock(&sg->guest_table_lock);
- return 0;
- }
- spin_unlock(&sg->guest_table_lock);
- /* Make sgt read-only in parent gmap page table */
- raddr = (saddr & _REGION3_MASK) | _SHADOW_RMAP_REGION3;
- origin = sgt & _REGION_ENTRY_ORIGIN;
- offset = ((sgt & _REGION_ENTRY_OFFSET) >> 6) * PAGE_SIZE;
- len = ((sgt & _REGION_ENTRY_LENGTH) + 1) * PAGE_SIZE - offset;
- rc = gmap_protect_rmap(sg, raddr, origin + offset, len);
- spin_lock(&sg->guest_table_lock);
- if (!rc) {
- table = gmap_table_walk(sg, saddr, 2);
- if (!table || (*table & _REGION_ENTRY_ORIGIN) != s_sgt)
- rc = -EAGAIN; /* Race with unshadow */
- else
- *table &= ~_REGION_ENTRY_INVALID;
- } else {
- gmap_unshadow_sgt(sg, raddr);
- }
- spin_unlock(&sg->guest_table_lock);
- return rc;
-out_free:
- spin_unlock(&sg->guest_table_lock);
- __free_pages(page, CRST_ALLOC_ORDER);
- return rc;
-}
-EXPORT_SYMBOL_GPL(gmap_shadow_sgt);
-
-static void gmap_pgste_set_pgt_addr(struct ptdesc *ptdesc, unsigned long pgt_addr)
-{
- unsigned long *pgstes = page_to_virt(ptdesc_page(ptdesc));
-
- pgstes += _PAGE_ENTRIES;
-
- pgstes[0] &= ~PGSTE_ST2_MASK;
- pgstes[1] &= ~PGSTE_ST2_MASK;
- pgstes[2] &= ~PGSTE_ST2_MASK;
- pgstes[3] &= ~PGSTE_ST2_MASK;
-
- pgstes[0] |= (pgt_addr >> 16) & PGSTE_ST2_MASK;
- pgstes[1] |= pgt_addr & PGSTE_ST2_MASK;
- pgstes[2] |= (pgt_addr << 16) & PGSTE_ST2_MASK;
- pgstes[3] |= (pgt_addr << 32) & PGSTE_ST2_MASK;
-}
-
-/**
- * gmap_shadow_pgt - instantiate a shadow page table
- * @sg: pointer to the shadow guest address space structure
- * @saddr: faulting address in the shadow gmap
- * @pgt: parent gmap address of the page table to get shadowed
- * @fake: pgt references contiguous guest memory block, not a pgtable
- *
- * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the
- * shadow table structure is incomplete, -ENOMEM if out of memory,
- * -EFAULT if an address in the parent gmap could not be resolved and
- *
- * Called with gmap->mm->mmap_lock in read
- */
-int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt,
- int fake)
-{
- unsigned long raddr, origin;
- unsigned long *table;
- struct ptdesc *ptdesc;
- phys_addr_t s_pgt;
- int rc;
-
- BUG_ON(!gmap_is_shadow(sg) || (pgt & _SEGMENT_ENTRY_LARGE));
- /* Allocate a shadow page table */
- ptdesc = page_table_alloc_pgste(sg->mm);
- if (!ptdesc)
- return -ENOMEM;
- origin = pgt & _SEGMENT_ENTRY_ORIGIN;
- if (fake)
- origin |= GMAP_SHADOW_FAKE_TABLE;
- gmap_pgste_set_pgt_addr(ptdesc, origin);
- s_pgt = page_to_phys(ptdesc_page(ptdesc));
- /* Install shadow page table */
- spin_lock(&sg->guest_table_lock);
- table = gmap_table_walk(sg, saddr, 1); /* get segment pointer */
- if (!table) {
- rc = -EAGAIN; /* Race with unshadow */
- goto out_free;
- }
- if (!(*table & _SEGMENT_ENTRY_INVALID)) {
- rc = 0; /* Already established */
- goto out_free;
- } else if (*table & _SEGMENT_ENTRY_ORIGIN) {
- rc = -EAGAIN; /* Race with shadow */
- goto out_free;
- }
- /* mark as invalid as long as the parent table is not protected */
- *table = (unsigned long) s_pgt | _SEGMENT_ENTRY |
- (pgt & _SEGMENT_ENTRY_PROTECT) | _SEGMENT_ENTRY_INVALID;
- if (fake) {
- /* nothing to protect for fake tables */
- *table &= ~_SEGMENT_ENTRY_INVALID;
- spin_unlock(&sg->guest_table_lock);
- return 0;
- }
- spin_unlock(&sg->guest_table_lock);
- /* Make pgt read-only in parent gmap page table (not the pgste) */
- raddr = (saddr & _SEGMENT_MASK) | _SHADOW_RMAP_SEGMENT;
- origin = pgt & _SEGMENT_ENTRY_ORIGIN & PAGE_MASK;
- rc = gmap_protect_rmap(sg, raddr, origin, PAGE_SIZE);
- spin_lock(&sg->guest_table_lock);
- if (!rc) {
- table = gmap_table_walk(sg, saddr, 1);
- if (!table || (*table & _SEGMENT_ENTRY_ORIGIN) != s_pgt)
- rc = -EAGAIN; /* Race with unshadow */
- else
- *table &= ~_SEGMENT_ENTRY_INVALID;
- } else {
- gmap_unshadow_pgt(sg, raddr);
- }
- spin_unlock(&sg->guest_table_lock);
- return rc;
-out_free:
- spin_unlock(&sg->guest_table_lock);
- page_table_free_pgste(ptdesc);
- return rc;
-
-}
-EXPORT_SYMBOL_GPL(gmap_shadow_pgt);
-
-/**
- * gmap_shadow_page - create a shadow page mapping
- * @sg: pointer to the shadow guest address space structure
- * @saddr: faulting address in the shadow gmap
- * @pte: pte in parent gmap address space to get shadowed
- *
- * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the
- * shadow table structure is incomplete, -ENOMEM if out of memory and
- * -EFAULT if an address in the parent gmap could not be resolved.
- *
- * Called with sg->mm->mmap_lock in read.
- */
-int gmap_shadow_page(struct gmap *sg, unsigned long saddr, pte_t pte)
-{
- struct gmap *parent;
- struct gmap_rmap *rmap;
- unsigned long vmaddr, paddr;
- spinlock_t *ptl;
- pte_t *sptep, *tptep;
- int prot;
- int rc;
-
- BUG_ON(!gmap_is_shadow(sg));
- parent = sg->parent;
- prot = (pte_val(pte) & _PAGE_PROTECT) ? PROT_READ : PROT_WRITE;
-
- rmap = kzalloc(sizeof(*rmap), GFP_KERNEL_ACCOUNT);
- if (!rmap)
- return -ENOMEM;
- rmap->raddr = (saddr & PAGE_MASK) | _SHADOW_RMAP_PGTABLE;
-
- while (1) {
- paddr = pte_val(pte) & PAGE_MASK;
- vmaddr = __gmap_translate(parent, paddr);
- if (IS_ERR_VALUE(vmaddr)) {
- rc = vmaddr;
- break;
- }
- rc = radix_tree_preload(GFP_KERNEL_ACCOUNT);
- if (rc)
- break;
- rc = -EAGAIN;
- sptep = gmap_pte_op_walk(parent, paddr, &ptl);
- if (sptep) {
- spin_lock(&sg->guest_table_lock);
- /* Get page table pointer */
- tptep = (pte_t *) gmap_table_walk(sg, saddr, 0);
- if (!tptep) {
- spin_unlock(&sg->guest_table_lock);
- gmap_pte_op_end(sptep, ptl);
- radix_tree_preload_end();
- break;
- }
- rc = ptep_shadow_pte(sg->mm, saddr, sptep, tptep, pte);
- if (rc > 0) {
- /* Success and a new mapping */
- gmap_insert_rmap(sg, vmaddr, rmap);
- rmap = NULL;
- rc = 0;
- }
- gmap_pte_op_end(sptep, ptl);
- spin_unlock(&sg->guest_table_lock);
- }
- radix_tree_preload_end();
- if (!rc)
- break;
- rc = gmap_pte_op_fixup(parent, paddr, vmaddr, prot);
- if (rc)
- break;
- }
- kfree(rmap);
- return rc;
-}
-EXPORT_SYMBOL_GPL(gmap_shadow_page);
-
-/*
- * gmap_shadow_notify - handle notifications for shadow gmap
- *
- * Called with sg->parent->shadow_lock.
- */
-static void gmap_shadow_notify(struct gmap *sg, unsigned long vmaddr,
- unsigned long gaddr)
-{
- struct gmap_rmap *rmap, *rnext, *head;
- unsigned long start, end, bits, raddr;
-
- BUG_ON(!gmap_is_shadow(sg));
-
- spin_lock(&sg->guest_table_lock);
- if (sg->removed) {
- spin_unlock(&sg->guest_table_lock);
- return;
- }
- /* Check for top level table */
- start = sg->orig_asce & _ASCE_ORIGIN;
- end = start + ((sg->orig_asce & _ASCE_TABLE_LENGTH) + 1) * PAGE_SIZE;
- if (!(sg->orig_asce & _ASCE_REAL_SPACE) && gaddr >= start &&
- gaddr < end) {
- /* The complete shadow table has to go */
- gmap_unshadow(sg);
- spin_unlock(&sg->guest_table_lock);
- list_del(&sg->list);
- gmap_put(sg);
- return;
- }
- /* Remove the page table tree from on specific entry */
- head = radix_tree_delete(&sg->host_to_rmap, vmaddr >> PAGE_SHIFT);
- gmap_for_each_rmap_safe(rmap, rnext, head) {
- bits = rmap->raddr & _SHADOW_RMAP_MASK;
- raddr = rmap->raddr ^ bits;
- switch (bits) {
- case _SHADOW_RMAP_REGION1:
- gmap_unshadow_r2t(sg, raddr);
- break;
- case _SHADOW_RMAP_REGION2:
- gmap_unshadow_r3t(sg, raddr);
- break;
- case _SHADOW_RMAP_REGION3:
- gmap_unshadow_sgt(sg, raddr);
- break;
- case _SHADOW_RMAP_SEGMENT:
- gmap_unshadow_pgt(sg, raddr);
- break;
- case _SHADOW_RMAP_PGTABLE:
- gmap_unshadow_page(sg, raddr);
- break;
- }
- kfree(rmap);
- }
- spin_unlock(&sg->guest_table_lock);
-}
-
-/**
- * ptep_notify - call all invalidation callbacks for a specific pte.
- * @mm: pointer to the process mm_struct
- * @vmaddr: virtual address in the process address space
- * @pte: pointer to the page table entry
- * @bits: bits from the pgste that caused the notify call
- *
- * This function is assumed to be called with the page table lock held
- * for the pte to notify.
- */
-void ptep_notify(struct mm_struct *mm, unsigned long vmaddr,
- pte_t *pte, unsigned long bits)
-{
- unsigned long offset, gaddr = 0;
- struct gmap *gmap, *sg, *next;
-
- offset = ((unsigned long) pte) & (255 * sizeof(pte_t));
- offset = offset * (PAGE_SIZE / sizeof(pte_t));
- rcu_read_lock();
- list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) {
- spin_lock(&gmap->guest_table_lock);
- gaddr = host_to_guest_lookup(gmap, vmaddr) + offset;
- spin_unlock(&gmap->guest_table_lock);
- if (!IS_GADDR_VALID(gaddr))
- continue;
-
- if (!list_empty(&gmap->children) && (bits & PGSTE_VSIE_BIT)) {
- spin_lock(&gmap->shadow_lock);
- list_for_each_entry_safe(sg, next,
- &gmap->children, list)
- gmap_shadow_notify(sg, vmaddr, gaddr);
- spin_unlock(&gmap->shadow_lock);
- }
- if (bits & PGSTE_IN_BIT)
- gmap_call_notifier(gmap, gaddr, gaddr + PAGE_SIZE - 1);
- }
- rcu_read_unlock();
-}
-EXPORT_SYMBOL_GPL(ptep_notify);
-
-static void pmdp_notify_gmap(struct gmap *gmap, pmd_t *pmdp,
- unsigned long gaddr)
-{
- set_pmd(pmdp, clear_pmd_bit(*pmdp, __pgprot(_SEGMENT_ENTRY_GMAP_IN)));
- gmap_call_notifier(gmap, gaddr, gaddr + HPAGE_SIZE - 1);
-}
-
-/**
- * gmap_pmdp_xchg - exchange a gmap pmd with another
- * @gmap: pointer to the guest address space structure
- * @pmdp: pointer to the pmd entry
- * @new: replacement entry
- * @gaddr: the affected guest address
- *
- * This function is assumed to be called with the guest_table_lock
- * held.
- */
-static void gmap_pmdp_xchg(struct gmap *gmap, pmd_t *pmdp, pmd_t new,
- unsigned long gaddr)
-{
- gaddr &= HPAGE_MASK;
- pmdp_notify_gmap(gmap, pmdp, gaddr);
- new = clear_pmd_bit(new, __pgprot(_SEGMENT_ENTRY_GMAP_IN));
- if (machine_has_tlb_guest())
- __pmdp_idte(gaddr, (pmd_t *)pmdp, IDTE_GUEST_ASCE, gmap->asce,
- IDTE_GLOBAL);
- else
- __pmdp_idte(gaddr, (pmd_t *)pmdp, 0, 0, IDTE_GLOBAL);
- set_pmd(pmdp, new);
-}
-
-static void gmap_pmdp_clear(struct mm_struct *mm, unsigned long vmaddr,
- int purge)
-{
- pmd_t *pmdp;
- struct gmap *gmap;
- unsigned long gaddr;
-
- rcu_read_lock();
- list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) {
- spin_lock(&gmap->guest_table_lock);
- pmdp = host_to_guest_pmd_delete(gmap, vmaddr, &gaddr);
- if (pmdp) {
- pmdp_notify_gmap(gmap, pmdp, gaddr);
- WARN_ON(pmd_val(*pmdp) & ~(_SEGMENT_ENTRY_HARDWARE_BITS_LARGE |
- _SEGMENT_ENTRY_GMAP_UC |
- _SEGMENT_ENTRY));
- if (purge)
- __pmdp_cspg(pmdp);
- set_pmd(pmdp, __pmd(_SEGMENT_ENTRY_EMPTY));
- }
- spin_unlock(&gmap->guest_table_lock);
- }
- rcu_read_unlock();
-}
-
-/**
- * gmap_pmdp_invalidate - invalidate all affected guest pmd entries without
- * flushing
- * @mm: pointer to the process mm_struct
- * @vmaddr: virtual address in the process address space
- */
-void gmap_pmdp_invalidate(struct mm_struct *mm, unsigned long vmaddr)
-{
- gmap_pmdp_clear(mm, vmaddr, 0);
-}
-EXPORT_SYMBOL_GPL(gmap_pmdp_invalidate);
-
-/**
- * gmap_pmdp_idte_local - invalidate and clear a guest pmd entry
- * @mm: pointer to the process mm_struct
- * @vmaddr: virtual address in the process address space
- */
-void gmap_pmdp_idte_local(struct mm_struct *mm, unsigned long vmaddr)
-{
- unsigned long gaddr;
- struct gmap *gmap;
- pmd_t *pmdp;
-
- rcu_read_lock();
- list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) {
- spin_lock(&gmap->guest_table_lock);
- pmdp = host_to_guest_pmd_delete(gmap, vmaddr, &gaddr);
- if (pmdp) {
- pmdp_notify_gmap(gmap, pmdp, gaddr);
- WARN_ON(pmd_val(*pmdp) & ~(_SEGMENT_ENTRY_HARDWARE_BITS_LARGE |
- _SEGMENT_ENTRY_GMAP_UC |
- _SEGMENT_ENTRY));
- if (machine_has_tlb_guest())
- __pmdp_idte(gaddr, pmdp, IDTE_GUEST_ASCE,
- gmap->asce, IDTE_LOCAL);
- else
- __pmdp_idte(gaddr, pmdp, 0, 0, IDTE_LOCAL);
- *pmdp = __pmd(_SEGMENT_ENTRY_EMPTY);
- }
- spin_unlock(&gmap->guest_table_lock);
- }
- rcu_read_unlock();
-}
-EXPORT_SYMBOL_GPL(gmap_pmdp_idte_local);
-
-/**
- * gmap_pmdp_idte_global - invalidate and clear a guest pmd entry
- * @mm: pointer to the process mm_struct
- * @vmaddr: virtual address in the process address space
- */
-void gmap_pmdp_idte_global(struct mm_struct *mm, unsigned long vmaddr)
-{
- unsigned long gaddr;
- struct gmap *gmap;
- pmd_t *pmdp;
-
- rcu_read_lock();
- list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) {
- spin_lock(&gmap->guest_table_lock);
- pmdp = host_to_guest_pmd_delete(gmap, vmaddr, &gaddr);
- if (pmdp) {
- pmdp_notify_gmap(gmap, pmdp, gaddr);
- WARN_ON(pmd_val(*pmdp) & ~(_SEGMENT_ENTRY_HARDWARE_BITS_LARGE |
- _SEGMENT_ENTRY_GMAP_UC |
- _SEGMENT_ENTRY));
- if (machine_has_tlb_guest())
- __pmdp_idte(gaddr, pmdp, IDTE_GUEST_ASCE,
- gmap->asce, IDTE_GLOBAL);
- else
- __pmdp_idte(gaddr, pmdp, 0, 0, IDTE_GLOBAL);
- *pmdp = __pmd(_SEGMENT_ENTRY_EMPTY);
- }
- spin_unlock(&gmap->guest_table_lock);
- }
- rcu_read_unlock();
-}
-EXPORT_SYMBOL_GPL(gmap_pmdp_idte_global);
-
-/**
- * gmap_test_and_clear_dirty_pmd - test and reset segment dirty status
- * @gmap: pointer to guest address space
- * @pmdp: pointer to the pmd to be tested
- * @gaddr: virtual address in the guest address space
- *
- * This function is assumed to be called with the guest_table_lock
- * held.
- */
-static bool gmap_test_and_clear_dirty_pmd(struct gmap *gmap, pmd_t *pmdp,
- unsigned long gaddr)
-{
- if (pmd_val(*pmdp) & _SEGMENT_ENTRY_INVALID)
- return false;
-
- /* Already protected memory, which did not change is clean */
- if (pmd_val(*pmdp) & _SEGMENT_ENTRY_PROTECT &&
- !(pmd_val(*pmdp) & _SEGMENT_ENTRY_GMAP_UC))
- return false;
-
- /* Clear UC indication and reset protection */
- set_pmd(pmdp, clear_pmd_bit(*pmdp, __pgprot(_SEGMENT_ENTRY_GMAP_UC)));
- gmap_protect_pmd(gmap, gaddr, pmdp, PROT_READ, 0);
- return true;
-}
-
-/**
- * gmap_sync_dirty_log_pmd - set bitmap based on dirty status of segment
- * @gmap: pointer to guest address space
- * @bitmap: dirty bitmap for this pmd
- * @gaddr: virtual address in the guest address space
- * @vmaddr: virtual address in the host address space
- *
- * This function is assumed to be called with the guest_table_lock
- * held.
- */
-void gmap_sync_dirty_log_pmd(struct gmap *gmap, unsigned long bitmap[4],
- unsigned long gaddr, unsigned long vmaddr)
-{
- int i;
- pmd_t *pmdp;
- pte_t *ptep;
- spinlock_t *ptl;
-
- pmdp = gmap_pmd_op_walk(gmap, gaddr);
- if (!pmdp)
- return;
-
- if (pmd_leaf(*pmdp)) {
- if (gmap_test_and_clear_dirty_pmd(gmap, pmdp, gaddr))
- bitmap_fill(bitmap, _PAGE_ENTRIES);
- } else {
- for (i = 0; i < _PAGE_ENTRIES; i++, vmaddr += PAGE_SIZE) {
- ptep = pte_alloc_map_lock(gmap->mm, pmdp, vmaddr, &ptl);
- if (!ptep)
- continue;
- if (ptep_test_and_clear_uc(gmap->mm, vmaddr, ptep))
- set_bit(i, bitmap);
- pte_unmap_unlock(ptep, ptl);
- }
- }
- gmap_pmd_op_end(gmap, pmdp);
-}
-EXPORT_SYMBOL_GPL(gmap_sync_dirty_log_pmd);
-
-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
-static int thp_split_walk_pmd_entry(pmd_t *pmd, unsigned long addr,
- unsigned long end, struct mm_walk *walk)
-{
- struct vm_area_struct *vma = walk->vma;
-
- split_huge_pmd(vma, pmd, addr);
- return 0;
-}
-
-static const struct mm_walk_ops thp_split_walk_ops = {
- .pmd_entry = thp_split_walk_pmd_entry,
- .walk_lock = PGWALK_WRLOCK_VERIFY,
-};
-
-static inline void thp_split_mm(struct mm_struct *mm)
-{
- struct vm_area_struct *vma;
- VMA_ITERATOR(vmi, mm, 0);
-
- for_each_vma(vmi, vma) {
- vm_flags_mod(vma, VM_NOHUGEPAGE, VM_HUGEPAGE);
- walk_page_vma(vma, &thp_split_walk_ops, NULL);
- }
- mm->def_flags |= VM_NOHUGEPAGE;
-}
-#else
-static inline void thp_split_mm(struct mm_struct *mm)
-{
-}
-#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
-
-/*
- * switch on pgstes for its userspace process (for kvm)
- */
-int s390_enable_sie(void)
-{
- struct mm_struct *mm = current->mm;
-
- /* Do we have pgstes? if yes, we are done */
- if (mm_has_pgste(mm))
- return 0;
- mmap_write_lock(mm);
- mm->context.has_pgste = 1;
- /* split thp mappings and disable thp for future mappings */
- thp_split_mm(mm);
- mmap_write_unlock(mm);
- return 0;
-}
-EXPORT_SYMBOL_GPL(s390_enable_sie);
-
-/*
- * Enable storage key handling from now on and initialize the storage
- * keys with the default key.
- */
-static int __s390_enable_skey_pte(pte_t *pte, unsigned long addr,
- unsigned long next, struct mm_walk *walk)
-{
- /* Clear storage key */
- ptep_zap_key(walk->mm, addr, pte);
- return 0;
-}
-
-/*
- * Give a chance to schedule after setting a key to 256 pages.
- * We only hold the mm lock, which is a rwsem and the kvm srcu.
- * Both can sleep.
- */
-static int __s390_enable_skey_pmd(pmd_t *pmd, unsigned long addr,
- unsigned long next, struct mm_walk *walk)
-{
- cond_resched();
- return 0;
-}
-
-static int __s390_enable_skey_hugetlb(pte_t *pte, unsigned long addr,
- unsigned long hmask, unsigned long next,
- struct mm_walk *walk)
-{
- pmd_t *pmd = (pmd_t *)pte;
- unsigned long start, end;
- struct folio *folio = page_folio(pmd_page(*pmd));
-
- /*
- * The write check makes sure we do not set a key on shared
- * memory. This is needed as the walker does not differentiate
- * between actual guest memory and the process executable or
- * shared libraries.
- */
- if (pmd_val(*pmd) & _SEGMENT_ENTRY_INVALID ||
- !(pmd_val(*pmd) & _SEGMENT_ENTRY_WRITE))
- return 0;
-
- start = pmd_val(*pmd) & HPAGE_MASK;
- end = start + HPAGE_SIZE;
- __storage_key_init_range(start, end);
- set_bit(PG_arch_1, &folio->flags.f);
- cond_resched();
- return 0;
-}
-
-static const struct mm_walk_ops enable_skey_walk_ops = {
- .hugetlb_entry = __s390_enable_skey_hugetlb,
- .pte_entry = __s390_enable_skey_pte,
- .pmd_entry = __s390_enable_skey_pmd,
- .walk_lock = PGWALK_WRLOCK,
-};
-
-int s390_enable_skey(void)
-{
- struct mm_struct *mm = current->mm;
- int rc = 0;
-
- mmap_write_lock(mm);
- if (mm_uses_skeys(mm))
- goto out_up;
-
- mm->context.uses_skeys = 1;
- rc = gmap_helper_disable_cow_sharing();
- if (rc) {
- mm->context.uses_skeys = 0;
- goto out_up;
- }
- walk_page_range(mm, 0, TASK_SIZE, &enable_skey_walk_ops, NULL);
-
-out_up:
- mmap_write_unlock(mm);
- return rc;
-}
-EXPORT_SYMBOL_GPL(s390_enable_skey);
-
-/*
- * Reset CMMA state, make all pages stable again.
- */
-static int __s390_reset_cmma(pte_t *pte, unsigned long addr,
- unsigned long next, struct mm_walk *walk)
-{
- ptep_zap_unused(walk->mm, addr, pte, 1);
- return 0;
-}
-
-static const struct mm_walk_ops reset_cmma_walk_ops = {
- .pte_entry = __s390_reset_cmma,
- .walk_lock = PGWALK_WRLOCK,
-};
-
-void s390_reset_cmma(struct mm_struct *mm)
-{
- mmap_write_lock(mm);
- walk_page_range(mm, 0, TASK_SIZE, &reset_cmma_walk_ops, NULL);
- mmap_write_unlock(mm);
-}
-EXPORT_SYMBOL_GPL(s390_reset_cmma);
-
-#define GATHER_GET_PAGES 32
-
-struct reset_walk_state {
- unsigned long next;
- unsigned long count;
- unsigned long pfns[GATHER_GET_PAGES];
-};
-
-static int s390_gather_pages(pte_t *ptep, unsigned long addr,
- unsigned long next, struct mm_walk *walk)
-{
- struct reset_walk_state *p = walk->private;
- pte_t pte = READ_ONCE(*ptep);
-
- if (pte_present(pte)) {
- /* we have a reference from the mapping, take an extra one */
- get_page(phys_to_page(pte_val(pte)));
- p->pfns[p->count] = phys_to_pfn(pte_val(pte));
- p->next = next;
- p->count++;
- }
- return p->count >= GATHER_GET_PAGES;
-}
-
-static const struct mm_walk_ops gather_pages_ops = {
- .pte_entry = s390_gather_pages,
- .walk_lock = PGWALK_RDLOCK,
-};
-
-/*
- * Call the Destroy secure page UVC on each page in the given array of PFNs.
- * Each page needs to have an extra reference, which will be released here.
- */
-void s390_uv_destroy_pfns(unsigned long count, unsigned long *pfns)
-{
- struct folio *folio;
- unsigned long i;
-
- for (i = 0; i < count; i++) {
- folio = pfn_folio(pfns[i]);
- /* we always have an extra reference */
- uv_destroy_folio(folio);
- /* get rid of the extra reference */
- folio_put(folio);
- cond_resched();
- }
-}
-EXPORT_SYMBOL_GPL(s390_uv_destroy_pfns);
-
-/**
- * __s390_uv_destroy_range - Call the destroy secure page UVC on each page
- * in the given range of the given address space.
- * @mm: the mm to operate on
- * @start: the start of the range
- * @end: the end of the range
- * @interruptible: if not 0, stop when a fatal signal is received
- *
- * Walk the given range of the given address space and call the destroy
- * secure page UVC on each page. Optionally exit early if a fatal signal is
- * pending.
- *
- * Return: 0 on success, -EINTR if the function stopped before completing
- */
-int __s390_uv_destroy_range(struct mm_struct *mm, unsigned long start,
- unsigned long end, bool interruptible)
-{
- struct reset_walk_state state = { .next = start };
- int r = 1;
-
- while (r > 0) {
- state.count = 0;
- mmap_read_lock(mm);
- r = walk_page_range(mm, state.next, end, &gather_pages_ops, &state);
- mmap_read_unlock(mm);
- cond_resched();
- s390_uv_destroy_pfns(state.count, state.pfns);
- if (interruptible && fatal_signal_pending(current))
- return -EINTR;
- }
- return 0;
-}
-EXPORT_SYMBOL_GPL(__s390_uv_destroy_range);
-
-/**
- * s390_replace_asce - Try to replace the current ASCE of a gmap with a copy
- * @gmap: the gmap whose ASCE needs to be replaced
- *
- * If the ASCE is a SEGMENT type then this function will return -EINVAL,
- * otherwise the pointers in the host_to_guest radix tree will keep pointing
- * to the wrong pages, causing use-after-free and memory corruption.
- * If the allocation of the new top level page table fails, the ASCE is not
- * replaced.
- * In any case, the old ASCE is always removed from the gmap CRST list.
- * Therefore the caller has to make sure to save a pointer to it
- * beforehand, unless a leak is actually intended.
- */
-int s390_replace_asce(struct gmap *gmap)
-{
- unsigned long asce;
- struct page *page;
- void *table;
-
- /* Replacing segment type ASCEs would cause serious issues */
- if ((gmap->asce & _ASCE_TYPE_MASK) == _ASCE_TYPE_SEGMENT)
- return -EINVAL;
-
- page = gmap_alloc_crst();
- if (!page)
- return -ENOMEM;
- table = page_to_virt(page);
- memcpy(table, gmap->table, 1UL << (CRST_ALLOC_ORDER + PAGE_SHIFT));
-
- /* Set new table origin while preserving existing ASCE control bits */
- asce = (gmap->asce & ~_ASCE_ORIGIN) | __pa(table);
- WRITE_ONCE(gmap->asce, asce);
- WRITE_ONCE(gmap->mm->context.gmap_asce, asce);
- WRITE_ONCE(gmap->table, table);
-
- return 0;
-}
-EXPORT_SYMBOL_GPL(s390_replace_asce);
projects / thirdparty / linux.git / commitdiff
