linux_dsm_epyc7002/arch/s390/include/asm/tlbflush.h
Martin Schwidefsky 44b6cc8130 s390/mm,kvm: flush gmap address space with IDTE
The __tlb_flush_mm() helper uses a global flush if the mm struct
has a gmap structure attached to it. Replace the global flush with
two individual flushes by means of the IDTE instruction if only a
single gmap is attached the the mm.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-08-24 09:23:55 +02:00

161 lines
3.8 KiB
C

#ifndef _S390_TLBFLUSH_H
#define _S390_TLBFLUSH_H
#include <linux/mm.h>
#include <linux/sched.h>
#include <asm/processor.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
/*
* Flush all TLB entries on the local CPU.
*/
static inline void __tlb_flush_local(void)
{
asm volatile("ptlb" : : : "memory");
}
/*
* Flush TLB entries for a specific ASCE on all CPUs
*/
static inline void __tlb_flush_idte(unsigned long asce)
{
/* Global TLB flush for the mm */
asm volatile(
" .insn rrf,0xb98e0000,0,%0,%1,0"
: : "a" (2048), "a" (asce) : "cc");
}
#ifdef CONFIG_SMP
void smp_ptlb_all(void);
/*
* Flush all TLB entries on all CPUs.
*/
static inline void __tlb_flush_global(void)
{
unsigned int dummy = 0;
csp(&dummy, 0, 0);
}
/*
* Flush TLB entries for a specific mm on all CPUs (in case gmap is used
* this implicates multiple ASCEs!).
*/
static inline void __tlb_flush_full(struct mm_struct *mm)
{
preempt_disable();
atomic_inc(&mm->context.flush_count);
if (cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id()))) {
/* Local TLB flush */
__tlb_flush_local();
} else {
/* Global TLB flush */
__tlb_flush_global();
/* Reset TLB flush mask */
cpumask_copy(mm_cpumask(mm), &mm->context.cpu_attach_mask);
}
atomic_dec(&mm->context.flush_count);
preempt_enable();
}
static inline void __tlb_flush_mm(struct mm_struct *mm)
{
unsigned long gmap_asce;
/*
* If the machine has IDTE we prefer to do a per mm flush
* on all cpus instead of doing a local flush if the mm
* only ran on the local cpu.
*/
preempt_disable();
atomic_inc(&mm->context.flush_count);
gmap_asce = READ_ONCE(mm->context.gmap_asce);
if (MACHINE_HAS_IDTE && gmap_asce != -1UL) {
if (gmap_asce)
__tlb_flush_idte(gmap_asce);
__tlb_flush_idte(mm->context.asce);
} else {
__tlb_flush_full(mm);
}
/* Reset TLB flush mask */
cpumask_copy(mm_cpumask(mm), &mm->context.cpu_attach_mask);
atomic_dec(&mm->context.flush_count);
preempt_enable();
}
static inline void __tlb_flush_kernel(void)
{
if (MACHINE_HAS_IDTE)
__tlb_flush_idte(init_mm.context.asce);
else
__tlb_flush_global();
}
#else
#define __tlb_flush_global() __tlb_flush_local()
#define __tlb_flush_full(mm) __tlb_flush_local()
/*
* Flush TLB entries for a specific ASCE on all CPUs.
*/
static inline void __tlb_flush_mm(struct mm_struct *mm)
{
__tlb_flush_local();
}
static inline void __tlb_flush_kernel(void)
{
__tlb_flush_local();
}
#endif
static inline void __tlb_flush_mm_lazy(struct mm_struct * mm)
{
if (mm->context.flush_mm) {
__tlb_flush_mm(mm);
mm->context.flush_mm = 0;
}
}
/*
* TLB flushing:
* flush_tlb() - flushes the current mm struct TLBs
* flush_tlb_all() - flushes all processes TLBs
* flush_tlb_mm(mm) - flushes the specified mm context TLB's
* flush_tlb_page(vma, vmaddr) - flushes one page
* flush_tlb_range(vma, start, end) - flushes a range of pages
* flush_tlb_kernel_range(start, end) - flushes a range of kernel pages
*/
/*
* flush_tlb_mm goes together with ptep_set_wrprotect for the
* copy_page_range operation and flush_tlb_range is related to
* ptep_get_and_clear for change_protection. ptep_set_wrprotect and
* ptep_get_and_clear do not flush the TLBs directly if the mm has
* only one user. At the end of the update the flush_tlb_mm and
* flush_tlb_range functions need to do the flush.
*/
#define flush_tlb() do { } while (0)
#define flush_tlb_all() do { } while (0)
#define flush_tlb_page(vma, addr) do { } while (0)
static inline void flush_tlb_mm(struct mm_struct *mm)
{
__tlb_flush_mm_lazy(mm);
}
static inline void flush_tlb_range(struct vm_area_struct *vma,
unsigned long start, unsigned long end)
{
__tlb_flush_mm_lazy(vma->vm_mm);
}
static inline void flush_tlb_kernel_range(unsigned long start,
unsigned long end)
{
__tlb_flush_kernel();
}
#endif /* _S390_TLBFLUSH_H */