s390/kvm: set guest page states to stable on re-ipl

The guest page state needs to be reset to stable for all pages
on initial program load via diagnose 0x308.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

diff --git a/arch/s390/include/asm/pgalloc.h b/arch/s390/include/asm/pgalloc.h
index e1408ddb94f8d6d5107561374bb759a37c5d8eb1..14d43c77d6cf9cea678d56dff8076b78346934c4 100644 (file)
--- a/arch/s390/include/asm/pgalloc.h
+++ b/arch/s390/include/asm/pgalloc.h
@@ -22,6 +22,7 @@ unsigned long *page_table_alloc(struct mm_struct *, unsigned long);
 void page_table_free(struct mm_struct *, unsigned long *);
 void page_table_free_rcu(struct mmu_gather *, unsigned long *);
 
+void page_table_reset_pgste(struct mm_struct *, unsigned long, unsigned long);
 int set_guest_storage_key(struct mm_struct *mm, unsigned long addr,
                          unsigned long key, bool nq);
 

diff --git a/arch/s390/kvm/diag.c b/arch/s390/kvm/diag.c
index 8216c0e0b2e299494ee297540ed0d7015e006858..6f9cfa50037246d8d37bb5dd81a21d643ff3f544 100644 (file)
--- a/arch/s390/kvm/diag.c
+++ b/arch/s390/kvm/diag.c
@@ -13,6 +13,7 @@
 
 #include <linux/kvm.h>
 #include <linux/kvm_host.h>
+#include <asm/pgalloc.h>
 #include <asm/virtio-ccw.h>
 #include "kvm-s390.h"
 #include "trace.h"
@@ -86,9 +87,11 @@ static int __diag_ipl_functions(struct kvm_vcpu *vcpu)
        switch (subcode) {
        case 3:
                vcpu->run->s390_reset_flags = KVM_S390_RESET_CLEAR;
+               page_table_reset_pgste(current->mm, 0, TASK_SIZE);
                break;
        case 4:
                vcpu->run->s390_reset_flags = 0;
+               page_table_reset_pgste(current->mm, 0, TASK_SIZE);
                break;
        default:
                return -EOPNOTSUPP;

diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c
index 9e2b4705dea2323300f9b3b725a4fd639e1c9a09..9c26b7aa96d97831b0190a1ea63216430bad1f18 100644 (file)
--- a/arch/s390/mm/pgtable.c
+++ b/arch/s390/mm/pgtable.c
@@ -879,6 +879,78 @@ static inline void page_table_free_pgste(unsigned long *table)
        __free_page(page);
 }
 
+static inline unsigned long page_table_reset_pte(struct mm_struct *mm,
+                       pmd_t *pmd, unsigned long addr, unsigned long end)
+{
+       pte_t *start_pte, *pte;
+       spinlock_t *ptl;
+       pgste_t pgste;
+
+       start_pte = pte_offset_map_lock(mm, pmd, addr, &ptl);
+       pte = start_pte;
+       do {
+               pgste = pgste_get_lock(pte);
+               pgste_val(pgste) &= ~_PGSTE_GPS_USAGE_MASK;
+               pgste_set_unlock(pte, pgste);
+       } while (pte++, addr += PAGE_SIZE, addr != end);
+       pte_unmap_unlock(start_pte, ptl);
+
+       return addr;
+}
+
+static inline unsigned long page_table_reset_pmd(struct mm_struct *mm,
+                       pud_t *pud, unsigned long addr, unsigned long end)
+{
+       unsigned long next;
+       pmd_t *pmd;
+
+       pmd = pmd_offset(pud, addr);
+       do {
+               next = pmd_addr_end(addr, end);
+               if (pmd_none_or_clear_bad(pmd))
+                       continue;
+               next = page_table_reset_pte(mm, pmd, addr, next);
+       } while (pmd++, addr = next, addr != end);
+
+       return addr;
+}
+
+static inline unsigned long page_table_reset_pud(struct mm_struct *mm,
+                       pgd_t *pgd, unsigned long addr, unsigned long end)
+{
+       unsigned long next;
+       pud_t *pud;
+
+       pud = pud_offset(pgd, addr);
+       do {
+               next = pud_addr_end(addr, end);
+               if (pud_none_or_clear_bad(pud))
+                       continue;
+               next = page_table_reset_pmd(mm, pud, addr, next);
+       } while (pud++, addr = next, addr != end);
+
+       return addr;
+}
+
+void page_table_reset_pgste(struct mm_struct *mm,
+                       unsigned long start, unsigned long end)
+{
+       unsigned long addr, next;
+       pgd_t *pgd;
+
+       addr = start;
+       down_read(&mm->mmap_sem);
+       pgd = pgd_offset(mm, addr);
+       do {
+               next = pgd_addr_end(addr, end);
+               if (pgd_none_or_clear_bad(pgd))
+                       continue;
+               next = page_table_reset_pud(mm, pgd, addr, next);
+       } while (pgd++, addr = next, addr != end);
+       up_read(&mm->mmap_sem);
+}
+EXPORT_SYMBOL(page_table_reset_pgste);
+
 int set_guest_storage_key(struct mm_struct *mm, unsigned long addr,
                          unsigned long key, bool nq)
 {