arm64: tlbflush: avoid writing RES0 bits

Several of the bits of the TLBI register operand are RES0 per the ARM
ARM, so TLBI operations should avoid writing non-zero values to these
bits.

This patch adds a macro __TLBI_VADDR(addr, asid) that creates the
operand register in the correct format and honors the RES0 bits.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Philip Elcan <pelcan@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>

diff --git a/arch/arm64/include/asm/tlbflush.h b/arch/arm64/include/asm/tlbflush.h
index 9e82dd7..dfc61d7 100644 (file)
--- a/arch/arm64/include/asm/tlbflush.h
+++ b/arch/arm64/include/asm/tlbflush.h
@@ -60,6 +60,15 @@
                __tlbi(op, (arg) | USER_ASID_FLAG);                             \
 } while (0)
 
+/* This macro creates a properly formatted VA operand for the TLBI */
+#define __TLBI_VADDR(addr, asid)                               \
+       ({                                                      \
+               unsigned long __ta = (addr) >> 12;              \
+               __ta &= GENMASK_ULL(43, 0);                     \
+               __ta |= (unsigned long)(asid) << 48;            \
+               __ta;                                           \
+       })
+
 /*
  *     TLB Management
  *     ==============
@@ -117,7 +126,7 @@ static inline void flush_tlb_all(void)
 
 static inline void flush_tlb_mm(struct mm_struct *mm)
 {
-       unsigned long asid = ASID(mm) << 48;
+       unsigned long asid = __TLBI_VADDR(0, ASID(mm));
 
        dsb(ishst);
        __tlbi(aside1is, asid);
@@ -128,7 +137,7 @@ static inline void flush_tlb_mm(struct mm_struct *mm)
 static inline void flush_tlb_page(struct vm_area_struct *vma,
                                  unsigned long uaddr)
 {
-       unsigned long addr = uaddr >> 12 | (ASID(vma->vm_mm) << 48);
+       unsigned long addr = __TLBI_VADDR(uaddr, ASID(vma->vm_mm));
 
        dsb(ishst);
        __tlbi(vale1is, addr);
@@ -146,7 +155,7 @@ static inline void __flush_tlb_range(struct vm_area_struct *vma,
                                     unsigned long start, unsigned long end,
                                     bool last_level)
 {
-       unsigned long asid = ASID(vma->vm_mm) << 48;
+       unsigned long asid = ASID(vma->vm_mm);
        unsigned long addr;
 
        if ((end - start) > MAX_TLB_RANGE) {
@@ -154,8 +163,8 @@ static inline void __flush_tlb_range(struct vm_area_struct *vma,
                return;
        }
 
-       start = asid | (start >> 12);
-       end = asid | (end >> 12);
+       start = __TLBI_VADDR(start, asid);
+       end = __TLBI_VADDR(end, asid);
 
        dsb(ishst);
        for (addr = start; addr < end; addr += 1 << (PAGE_SHIFT - 12)) {
@@ -185,8 +194,8 @@ static inline void flush_tlb_kernel_range(unsigned long start, unsigned long end
                return;
        }
 
-       start >>= 12;
-       end >>= 12;
+       start = __TLBI_VADDR(start, 0);
+       end = __TLBI_VADDR(end, 0);
 
        dsb(ishst);
        for (addr = start; addr < end; addr += 1 << (PAGE_SHIFT - 12))
@@ -202,7 +211,7 @@ static inline void flush_tlb_kernel_range(unsigned long start, unsigned long end
 static inline void __flush_tlb_pgtable(struct mm_struct *mm,
                                       unsigned long uaddr)
 {
-       unsigned long addr = uaddr >> 12 | (ASID(mm) << 48);
+       unsigned long addr = __TLBI_VADDR(uaddr, ASID(mm));
 
        __tlbi(vae1is, addr);
        __tlbi_user(vae1is, addr);