linux/arch/s390/include/asm/mmu.h
Martin Schwidefsky 0b46e0a3ec s390/kvm: remove delayed reallocation of page tables for KVM
Replacing a 2K page table with a 4K page table while a VMA is active
for the affected memory region is fundamentally broken. Rip out the
page table reallocation code and replace it with a simple system
control 'vm.allocate_pgste'. If the system control is set the page
tables for all processes are allocated as full 4K pages, even for
processes that do not need it.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-04-23 16:55:49 +02:00

45 lines
1.0 KiB
C

#ifndef __MMU_H
#define __MMU_H
#include <linux/cpumask.h>
#include <linux/errno.h>
typedef struct {
cpumask_t cpu_attach_mask;
atomic_t attach_count;
unsigned int flush_mm;
spinlock_t list_lock;
struct list_head pgtable_list;
struct list_head gmap_list;
unsigned long asce_bits;
unsigned long asce_limit;
unsigned long vdso_base;
/* The mmu context allocates 4K page tables. */
unsigned int alloc_pgste:1;
/* The mmu context uses extended page tables. */
unsigned int has_pgste:1;
/* The mmu context uses storage keys. */
unsigned int use_skey:1;
} mm_context_t;
#define INIT_MM_CONTEXT(name) \
.context.list_lock = __SPIN_LOCK_UNLOCKED(name.context.list_lock), \
.context.pgtable_list = LIST_HEAD_INIT(name.context.pgtable_list), \
.context.gmap_list = LIST_HEAD_INIT(name.context.gmap_list),
static inline int tprot(unsigned long addr)
{
int rc = -EFAULT;
asm volatile(
" tprot 0(%1),0\n"
"0: ipm %0\n"
" srl %0,28\n"
"1:\n"
EX_TABLE(0b,1b)
: "+d" (rc) : "a" (addr) : "cc");
return rc;
}
#endif