[RFC PATCH 02/11] arm64: tlb: Add DSB ISHST prior to TLBI in __flush_tlb_[kernel_]pgtable()

Will Deacon
2018-08-24T15:52:40Z

__flush_tlb_[kernel_]pgtable() rely on set_pXd() having a DSB after
writing the new table entry and therefore avoid the barrier prior to the
TLBI instruction.

In preparation for delaying our walk-cache invalidation on the unmap()
path, move the DSB into the TLB invalidation routines.

Signed-off-by: Will Deacon <will.deacon@arm.com>
---
arch/arm64/include/asm/tlbflush.h | 2 ++
1 file changed, 2 insertions(+)

diff --git a/arch/arm64/include/asm/tlbflush.h b/arch/arm64/include/asm/tlbflush.h
index 7e2a35424ca4..e257f8655b84 100644
--- a/arch/arm64/include/asm/tlbflush.h
+++ b/arch/arm64/include/asm/tlbflush.h
@@ -213,6 +213,7 @@ static inline void __flush_tlb_pgtable(struct mm_struct *mm,
{
unsigned long addr = __TLBI_VADDR(uaddr, ASID(mm));

+ dsb(ishst);
__tlbi(vae1is, addr);
__tlbi_user(vae1is, addr);
dsb(ish);
@@ -222,6 +223,7 @@ static inline void __flush_tlb_kernel_pgtable(unsigned long kaddr)
{
unsigned long addr = __TLBI_VADDR(kaddr, 0);

+ dsb(ishst);
__tlbi(vaae1is, addr);
dsb(ish);
}
--
2.1.4