powerpc/mm/radix: Add checks in slice code to catch radix usage
authorAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Fri, 29 Apr 2016 13:26:09 +0000 (23:26 +1000)
committerMichael Ellerman <mpe@ellerman.id.au>
Wed, 11 May 2016 11:53:46 +0000 (21:53 +1000)
Radix doesn't need slice support. Catch incorrect usage of slice code
when radix is enabled.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
arch/powerpc/mm/slice.c

index ee21b86..2b27458 100644 (file)
@@ -395,6 +395,7 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
 
        /* Sanity checks */
        BUG_ON(mm->task_size == 0);
+       VM_BUG_ON(radix_enabled());
 
        slice_dbg("slice_get_unmapped_area(mm=%p, psize=%d...\n", mm, psize);
        slice_dbg(" addr=%lx, len=%lx, flags=%lx, topdown=%d\n",
@@ -568,6 +569,16 @@ unsigned int get_slice_psize(struct mm_struct *mm, unsigned long addr)
        unsigned char *hpsizes;
        int index, mask_index;
 
+       /*
+        * Radix doesn't use slice, but can get enabled along with MMU_SLICE
+        */
+       if (radix_enabled()) {
+#ifdef CONFIG_PPC_64K_PAGES
+               return MMU_PAGE_64K;
+#else
+               return MMU_PAGE_4K;
+#endif
+       }
        if (addr < SLICE_LOW_TOP) {
                u64 lpsizes;
                lpsizes = mm->context.low_slices_psize;
@@ -605,6 +616,7 @@ void slice_set_user_psize(struct mm_struct *mm, unsigned int psize)
 
        slice_dbg("slice_set_user_psize(mm=%p, psize=%d)\n", mm, psize);
 
+       VM_BUG_ON(radix_enabled());
        spin_lock_irqsave(&slice_convert_lock, flags);
 
        old_psize = mm->context.user_psize;
@@ -649,6 +661,7 @@ void slice_set_range_psize(struct mm_struct *mm, unsigned long start,
 {
        struct slice_mask mask = slice_range_to_mask(start, len);
 
+       VM_BUG_ON(radix_enabled());
        slice_convert(mm, mask, psize);
 }
 
@@ -678,6 +691,9 @@ int is_hugepage_only_range(struct mm_struct *mm, unsigned long addr,
        struct slice_mask mask, available;
        unsigned int psize = mm->context.user_psize;
 
+       if (radix_enabled())
+               return 0;
+
        mask = slice_range_to_mask(addr, len);
        available = slice_mask_for_size(mm, psize);
 #ifdef CONFIG_PPC_64K_PAGES