linux/arch/powerpc/mm/tlb-radix.c
Aneesh Kumar K.V a145abf12c powerpc/mm/radix: Flush page walk cache when freeing page table
Even though a tlb_flush() does a flush with invalidate all cache,
we can end up doing an RCU page table free before calling tlb_flush().
That means we can have page walk cache entries even after we free the
page table pages. This can result in us doing wrong page table walk.

Avoid this by doing pwc flush on every page table free. We can't batch
the pwc flush, because the rcu call back function where we free the
page table pages doesn't have information of the mmu gather. Thus we
have to do a pwc on every page table page freed.

Note: I also removed the dummy tlb_flush_pgtable call functions for
hash 32.

Fixes: 1a472c9dba ("powerpc/mm/radix: Add tlbflush routines")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-06-10 16:14:52 +10:00

294 lines
7.4 KiB
C

/*
* TLB flush routines for radix kernels.
*
* Copyright 2015-2016, Aneesh Kumar K.V, IBM Corporation.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/mm.h>
#include <linux/hugetlb.h>
#include <linux/memblock.h>
#include <asm/tlb.h>
#include <asm/tlbflush.h>
static DEFINE_RAW_SPINLOCK(native_tlbie_lock);
#define RIC_FLUSH_TLB 0
#define RIC_FLUSH_PWC 1
#define RIC_FLUSH_ALL 2
static inline void __tlbiel_pid(unsigned long pid, int set,
unsigned long ric)
{
unsigned long rb,rs,prs,r;
rb = PPC_BIT(53); /* IS = 1 */
rb |= set << PPC_BITLSHIFT(51);
rs = ((unsigned long)pid) << PPC_BITLSHIFT(31);
prs = 1; /* process scoped */
r = 1; /* raidx format */
asm volatile("ptesync": : :"memory");
asm volatile(".long 0x7c000224 | (%0 << 11) | (%1 << 16) |"
"(%2 << 17) | (%3 << 18) | (%4 << 21)"
: : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(rs) : "memory");
asm volatile("ptesync": : :"memory");
}
/*
* We use 128 set in radix mode and 256 set in hpt mode.
*/
static inline void _tlbiel_pid(unsigned long pid, unsigned long ric)
{
int set;
for (set = 0; set < POWER9_TLB_SETS_RADIX ; set++) {
__tlbiel_pid(pid, set, ric);
}
return;
}
static inline void _tlbie_pid(unsigned long pid, unsigned long ric)
{
unsigned long rb,rs,prs,r;
rb = PPC_BIT(53); /* IS = 1 */
rs = pid << PPC_BITLSHIFT(31);
prs = 1; /* process scoped */
r = 1; /* raidx format */
asm volatile("ptesync": : :"memory");
asm volatile(".long 0x7c000264 | (%0 << 11) | (%1 << 16) |"
"(%2 << 17) | (%3 << 18) | (%4 << 21)"
: : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(rs) : "memory");
asm volatile("eieio; tlbsync; ptesync": : :"memory");
}
static inline void _tlbiel_va(unsigned long va, unsigned long pid,
unsigned long ap, unsigned long ric)
{
unsigned long rb,rs,prs,r;
rb = va & ~(PPC_BITMASK(52, 63));
rb |= ap << PPC_BITLSHIFT(58);
rs = pid << PPC_BITLSHIFT(31);
prs = 1; /* process scoped */
r = 1; /* raidx format */
asm volatile("ptesync": : :"memory");
asm volatile(".long 0x7c000224 | (%0 << 11) | (%1 << 16) |"
"(%2 << 17) | (%3 << 18) | (%4 << 21)"
: : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(rs) : "memory");
asm volatile("ptesync": : :"memory");
}
static inline void _tlbie_va(unsigned long va, unsigned long pid,
unsigned long ap, unsigned long ric)
{
unsigned long rb,rs,prs,r;
rb = va & ~(PPC_BITMASK(52, 63));
rb |= ap << PPC_BITLSHIFT(58);
rs = pid << PPC_BITLSHIFT(31);
prs = 1; /* process scoped */
r = 1; /* raidx format */
asm volatile("ptesync": : :"memory");
asm volatile(".long 0x7c000264 | (%0 << 11) | (%1 << 16) |"
"(%2 << 17) | (%3 << 18) | (%4 << 21)"
: : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(rs) : "memory");
asm volatile("eieio; tlbsync; ptesync": : :"memory");
}
/*
* Base TLB flushing operations:
*
* - 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 kernel pages
*
* - local_* variants of page and mm only apply to the current
* processor
*/
void radix__local_flush_tlb_mm(struct mm_struct *mm)
{
unsigned long pid;
preempt_disable();
pid = mm->context.id;
if (pid != MMU_NO_CONTEXT)
_tlbiel_pid(pid, RIC_FLUSH_ALL);
preempt_enable();
}
EXPORT_SYMBOL(radix__local_flush_tlb_mm);
void radix__local_flush_tlb_pwc(struct mmu_gather *tlb, unsigned long addr)
{
unsigned long pid;
struct mm_struct *mm = tlb->mm;
preempt_disable();
pid = mm->context.id;
if (pid != MMU_NO_CONTEXT)
_tlbiel_pid(pid, RIC_FLUSH_PWC);
preempt_enable();
}
EXPORT_SYMBOL(radix__local_flush_tlb_pwc);
void radix___local_flush_tlb_page(struct mm_struct *mm, unsigned long vmaddr,
unsigned long ap, int nid)
{
unsigned long pid;
preempt_disable();
pid = mm ? mm->context.id : 0;
if (pid != MMU_NO_CONTEXT)
_tlbiel_va(vmaddr, pid, ap, RIC_FLUSH_TLB);
preempt_enable();
}
void radix__local_flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr)
{
#ifdef CONFIG_HUGETLB_PAGE
/* need the return fix for nohash.c */
if (vma && is_vm_hugetlb_page(vma))
return __local_flush_hugetlb_page(vma, vmaddr);
#endif
radix___local_flush_tlb_page(vma ? vma->vm_mm : NULL, vmaddr,
mmu_get_ap(mmu_virtual_psize), 0);
}
EXPORT_SYMBOL(radix__local_flush_tlb_page);
#ifdef CONFIG_SMP
static int mm_is_core_local(struct mm_struct *mm)
{
return cpumask_subset(mm_cpumask(mm),
topology_sibling_cpumask(smp_processor_id()));
}
void radix__flush_tlb_mm(struct mm_struct *mm)
{
unsigned long pid;
preempt_disable();
pid = mm->context.id;
if (unlikely(pid == MMU_NO_CONTEXT))
goto no_context;
if (!mm_is_core_local(mm)) {
int lock_tlbie = !mmu_has_feature(MMU_FTR_LOCKLESS_TLBIE);
if (lock_tlbie)
raw_spin_lock(&native_tlbie_lock);
_tlbie_pid(pid, RIC_FLUSH_ALL);
if (lock_tlbie)
raw_spin_unlock(&native_tlbie_lock);
} else
_tlbiel_pid(pid, RIC_FLUSH_ALL);
no_context:
preempt_enable();
}
EXPORT_SYMBOL(radix__flush_tlb_mm);
void radix__flush_tlb_pwc(struct mmu_gather *tlb, unsigned long addr)
{
unsigned long pid;
struct mm_struct *mm = tlb->mm;
preempt_disable();
pid = mm->context.id;
if (unlikely(pid == MMU_NO_CONTEXT))
goto no_context;
if (!mm_is_core_local(mm)) {
int lock_tlbie = !mmu_has_feature(MMU_FTR_LOCKLESS_TLBIE);
if (lock_tlbie)
raw_spin_lock(&native_tlbie_lock);
_tlbie_pid(pid, RIC_FLUSH_PWC);
if (lock_tlbie)
raw_spin_unlock(&native_tlbie_lock);
} else
_tlbiel_pid(pid, RIC_FLUSH_PWC);
no_context:
preempt_enable();
}
EXPORT_SYMBOL(radix__flush_tlb_pwc);
void radix___flush_tlb_page(struct mm_struct *mm, unsigned long vmaddr,
unsigned long ap, int nid)
{
unsigned long pid;
preempt_disable();
pid = mm ? mm->context.id : 0;
if (unlikely(pid == MMU_NO_CONTEXT))
goto bail;
if (!mm_is_core_local(mm)) {
int lock_tlbie = !mmu_has_feature(MMU_FTR_LOCKLESS_TLBIE);
if (lock_tlbie)
raw_spin_lock(&native_tlbie_lock);
_tlbie_va(vmaddr, pid, ap, RIC_FLUSH_TLB);
if (lock_tlbie)
raw_spin_unlock(&native_tlbie_lock);
} else
_tlbiel_va(vmaddr, pid, ap, RIC_FLUSH_TLB);
bail:
preempt_enable();
}
void radix__flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr)
{
#ifdef CONFIG_HUGETLB_PAGE
if (vma && is_vm_hugetlb_page(vma))
return flush_hugetlb_page(vma, vmaddr);
#endif
radix___flush_tlb_page(vma ? vma->vm_mm : NULL, vmaddr,
mmu_get_ap(mmu_virtual_psize), 0);
}
EXPORT_SYMBOL(radix__flush_tlb_page);
#endif /* CONFIG_SMP */
void radix__flush_tlb_kernel_range(unsigned long start, unsigned long end)
{
int lock_tlbie = !mmu_has_feature(MMU_FTR_LOCKLESS_TLBIE);
if (lock_tlbie)
raw_spin_lock(&native_tlbie_lock);
_tlbie_pid(0, RIC_FLUSH_ALL);
if (lock_tlbie)
raw_spin_unlock(&native_tlbie_lock);
}
EXPORT_SYMBOL(radix__flush_tlb_kernel_range);
/*
* Currently, for range flushing, we just do a full mm flush. Because
* we use this in code path where we don' track the page size.
*/
void radix__flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
unsigned long end)
{
struct mm_struct *mm = vma->vm_mm;
radix__flush_tlb_mm(mm);
}
EXPORT_SYMBOL(radix__flush_tlb_range);
void radix__tlb_flush(struct mmu_gather *tlb)
{
struct mm_struct *mm = tlb->mm;
radix__flush_tlb_mm(mm);
}