s390/mm: recfactor global pgste updates

Replace the s390 specific page table walker for the pgste updates
with a call to the common code walk_page_range function.
There are now two pte modification functions, one for the reset
of the CMMA state and another one for the initialization of the
storage keys.

Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Dominik Dingel 2014-10-23 12:07:14 +02:00 committed by Martin Schwidefsky
parent e43b49a0cb
commit a13cff318c
4 changed files with 56 additions and 102 deletions

View File

@ -22,8 +22,6 @@ unsigned long *page_table_alloc(struct mm_struct *);
void page_table_free(struct mm_struct *, unsigned long *); void page_table_free(struct mm_struct *, unsigned long *);
void page_table_free_rcu(struct mmu_gather *, unsigned long *, unsigned long); void page_table_free_rcu(struct mmu_gather *, unsigned long *, unsigned long);
void page_table_reset_pgste(struct mm_struct *, unsigned long, unsigned long,
bool init_skey);
int set_guest_storage_key(struct mm_struct *mm, unsigned long addr, int set_guest_storage_key(struct mm_struct *mm, unsigned long addr,
unsigned long key, bool nq); unsigned long key, bool nq);

View File

@ -1747,6 +1747,7 @@ extern int vmem_add_mapping(unsigned long start, unsigned long size);
extern int vmem_remove_mapping(unsigned long start, unsigned long size); extern int vmem_remove_mapping(unsigned long start, unsigned long size);
extern int s390_enable_sie(void); extern int s390_enable_sie(void);
extern void s390_enable_skey(void); extern void s390_enable_skey(void);
extern void s390_reset_cmma(struct mm_struct *mm);
/* /*
* No page table caches to initialise * No page table caches to initialise

View File

@ -271,7 +271,7 @@ static int kvm_s390_mem_control(struct kvm *kvm, struct kvm_device_attr *attr)
case KVM_S390_VM_MEM_CLR_CMMA: case KVM_S390_VM_MEM_CLR_CMMA:
mutex_lock(&kvm->lock); mutex_lock(&kvm->lock);
idx = srcu_read_lock(&kvm->srcu); idx = srcu_read_lock(&kvm->srcu);
page_table_reset_pgste(kvm->arch.gmap->mm, 0, TASK_SIZE, false); s390_reset_cmma(kvm->arch.gmap->mm);
srcu_read_unlock(&kvm->srcu, idx); srcu_read_unlock(&kvm->srcu, idx);
mutex_unlock(&kvm->lock); mutex_unlock(&kvm->lock);
ret = 0; ret = 0;

View File

@ -834,99 +834,6 @@ static inline void page_table_free_pgste(unsigned long *table)
__free_page(page); __free_page(page);
} }
static inline unsigned long page_table_reset_pte(struct mm_struct *mm, pmd_t *pmd,
unsigned long addr, unsigned long end, bool init_skey)
{
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;
if (init_skey) {
unsigned long address;
pgste_val(pgste) &= ~(PGSTE_ACC_BITS | PGSTE_FP_BIT |
PGSTE_GR_BIT | PGSTE_GC_BIT);
/* skip invalid and not writable pages */
if (pte_val(*pte) & _PAGE_INVALID ||
!(pte_val(*pte) & _PAGE_WRITE)) {
pgste_set_unlock(pte, pgste);
continue;
}
address = pte_val(*pte) & PAGE_MASK;
page_set_storage_key(address, PAGE_DEFAULT_KEY, 1);
}
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, bool init_skey)
{
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, init_skey);
} 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, bool init_skey)
{
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, init_skey);
} while (pud++, addr = next, addr != end);
return addr;
}
void page_table_reset_pgste(struct mm_struct *mm, unsigned long start,
unsigned long end, bool init_skey)
{
unsigned long addr, next;
pgd_t *pgd;
down_write(&mm->mmap_sem);
if (init_skey && mm_use_skey(mm))
goto out_up;
addr = start;
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, init_skey);
} while (pgd++, addr = next, addr != end);
if (init_skey)
current->mm->context.use_skey = 1;
out_up:
up_write(&mm->mmap_sem);
}
EXPORT_SYMBOL(page_table_reset_pgste);
int set_guest_storage_key(struct mm_struct *mm, unsigned long addr, int set_guest_storage_key(struct mm_struct *mm, unsigned long addr,
unsigned long key, bool nq) unsigned long key, bool nq)
{ {
@ -992,11 +899,6 @@ static inline unsigned long *page_table_alloc_pgste(struct mm_struct *mm)
return NULL; return NULL;
} }
void page_table_reset_pgste(struct mm_struct *mm, unsigned long start,
unsigned long end, bool init_skey)
{
}
static inline void page_table_free_pgste(unsigned long *table) static inline void page_table_free_pgste(unsigned long *table)
{ {
} }
@ -1347,12 +1249,65 @@ EXPORT_SYMBOL_GPL(s390_enable_sie);
* Enable storage key handling from now on and initialize the storage * Enable storage key handling from now on and initialize the storage
* keys with the default key. * keys with the default key.
*/ */
static int __s390_enable_skey(pte_t *pte, unsigned long addr,
unsigned long next, struct mm_walk *walk)
{
unsigned long ptev;
pgste_t pgste;
pgste = pgste_get_lock(pte);
/* Clear storage key */
pgste_val(pgste) &= ~(PGSTE_ACC_BITS | PGSTE_FP_BIT |
PGSTE_GR_BIT | PGSTE_GC_BIT);
ptev = pte_val(*pte);
if (!(ptev & _PAGE_INVALID) && (ptev & _PAGE_WRITE))
page_set_storage_key(ptev & PAGE_MASK, PAGE_DEFAULT_KEY, 1);
pgste_set_unlock(pte, pgste);
return 0;
}
void s390_enable_skey(void) void s390_enable_skey(void)
{ {
page_table_reset_pgste(current->mm, 0, TASK_SIZE, true); struct mm_walk walk = { .pte_entry = __s390_enable_skey };
struct mm_struct *mm = current->mm;
down_write(&mm->mmap_sem);
if (mm_use_skey(mm))
goto out_up;
walk.mm = mm;
walk_page_range(0, TASK_SIZE, &walk);
mm->context.use_skey = 1;
out_up:
up_write(&mm->mmap_sem);
} }
EXPORT_SYMBOL_GPL(s390_enable_skey); 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)
{
pgste_t pgste;
pgste = pgste_get_lock(pte);
pgste_val(pgste) &= ~_PGSTE_GPS_USAGE_MASK;
pgste_set_unlock(pte, pgste);
return 0;
}
void s390_reset_cmma(struct mm_struct *mm)
{
struct mm_walk walk = { .pte_entry = __s390_reset_cmma };
down_write(&mm->mmap_sem);
walk.mm = mm;
walk_page_range(0, TASK_SIZE, &walk);
up_write(&mm->mmap_sem);
}
EXPORT_SYMBOL_GPL(s390_reset_cmma);
/* /*
* Test and reset if a guest page is dirty * Test and reset if a guest page is dirty
*/ */