powerpc/mm/slice: Convert slice_mask high slice to a bitmap

In followup patch we want to increase the va range which will result
in us requiring high_slices to have more than 64 bits. To enable this
convert high_slices to bitmap. We keep the number bits same in this patch
and later change that to higher value

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[mpe: Fold in fix to use bitmap_empty()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

diff --git a/arch/powerpc/include/asm/page_64.h b/arch/powerpc/include/asm/page_64.h
index 3e83d2a20b6f4d964cf638487dfbb670eac858a8..bd55ff751938070c4fa3deb0504b29b3d5f36542 100644 (file)
--- a/arch/powerpc/include/asm/page_64.h
+++ b/arch/powerpc/include/asm/page_64.h
@@ -98,19 +98,16 @@ extern u64 ppc64_pft_size;
 #define GET_LOW_SLICE_INDEX(addr)      ((addr) >> SLICE_LOW_SHIFT)
 #define GET_HIGH_SLICE_INDEX(addr)     ((addr) >> SLICE_HIGH_SHIFT)
 
+#ifndef __ASSEMBLY__
 /*
- * 1 bit per slice and we have one slice per 1TB
- * Right now we support only 64TB.
- * IF we change this we will have to change the type
- * of high_slices
+ * One bit per slice. We have lower slices which cover 256MB segments
+ * upto 4G range. That gets us 16 low slices. For the rest we track slices
+ * in 1TB size.
+ * 64 below is actually SLICE_NUM_HIGH to fixup complie errros
  */
-#define SLICE_MASK_SIZE 8
-
-#ifndef __ASSEMBLY__
-
 struct slice_mask {
        u16 low_slices;
-       u64 high_slices;
+       DECLARE_BITMAP(high_slices, 64);
 };
 
 struct mm_struct;

diff --git a/arch/powerpc/mm/slice.c b/arch/powerpc/mm/slice.c
index bf150557dba82f51e16955bf0e3da598813a059e..639c7171d1745c359b5376a7583edc2e88adca0b 100644 (file)
--- a/arch/powerpc/mm/slice.c
+++ b/arch/powerpc/mm/slice.c
@@ -36,11 +36,6 @@
 #include <asm/copro.h>
 #include <asm/hugetlb.h>
 
-/* some sanity checks */
-#if (H_PGTABLE_RANGE >> 43) > SLICE_MASK_SIZE
-#error H_PGTABLE_RANGE exceeds slice_mask high_slices size
-#endif
-
 static DEFINE_SPINLOCK(slice_convert_lock);
 
 
@@ -49,7 +44,7 @@ int _slice_debug = 1;
 
 static void slice_print_mask(const char *label, struct slice_mask mask)
 {
-       char    *p, buf[16 + 3 + 64 + 1];
+       char    *p, buf[SLICE_NUM_LOW + 3 + SLICE_NUM_HIGH + 1];
        int     i;
 
        if (!_slice_debug)
@@ -60,8 +55,12 @@ static void slice_print_mask(const char *label, struct slice_mask mask)
        *(p++) = ' ';
        *(p++) = '-';
        *(p++) = ' ';
-       for (i = 0; i < SLICE_NUM_HIGH; i++)
-               *(p++) = (mask.high_slices & (1ul << i)) ? '1' : '0';
+       for (i = 0; i < SLICE_NUM_HIGH; i++) {
+               if (test_bit(i, mask.high_slices))
+                       *(p++) = '1';
+               else
+                       *(p++) = '0';
+       }
        *(p++) = 0;
 
        printk(KERN_DEBUG "%s:%s\n", label, buf);
@@ -80,7 +79,10 @@ static struct slice_mask slice_range_to_mask(unsigned long start,
                                             unsigned long len)
 {
        unsigned long end = start + len - 1;
-       struct slice_mask ret = { 0, 0 };
+       struct slice_mask ret;
+
+       ret.low_slices = 0;
+       bitmap_zero(ret.high_slices, SLICE_NUM_HIGH);
 
        if (start < SLICE_LOW_TOP) {
                unsigned long mend = min(end, (SLICE_LOW_TOP - 1));
@@ -89,10 +91,13 @@ static struct slice_mask slice_range_to_mask(unsigned long start,
                        - (1u << GET_LOW_SLICE_INDEX(start));
        }
 
-       if ((start + len) > SLICE_LOW_TOP)
-               ret.high_slices = (1ul << (GET_HIGH_SLICE_INDEX(end) + 1))
-                       - (1ul << GET_HIGH_SLICE_INDEX(start));
+       if ((start + len) > SLICE_LOW_TOP) {
+               unsigned long start_index = GET_HIGH_SLICE_INDEX(start);
+               unsigned long align_end = ALIGN(end, (1UL << SLICE_HIGH_SHIFT));
+               unsigned long count = GET_HIGH_SLICE_INDEX(align_end) - start_index;
 
+               bitmap_set(ret.high_slices, start_index, count);
+       }
        return ret;
 }
 
@@ -129,9 +134,12 @@ static int slice_high_has_vma(struct mm_struct *mm, unsigned long slice)
 
 static struct slice_mask slice_mask_for_free(struct mm_struct *mm)
 {
-       struct slice_mask ret = { 0, 0 };
+       struct slice_mask ret;
        unsigned long i;
 
+       ret.low_slices = 0;
+       bitmap_zero(ret.high_slices, SLICE_NUM_HIGH);
+
        for (i = 0; i < SLICE_NUM_LOW; i++)
                if (!slice_low_has_vma(mm, i))
                        ret.low_slices |= 1u << i;
@@ -141,7 +149,7 @@ static struct slice_mask slice_mask_for_free(struct mm_struct *mm)
 
        for (i = 0; i < SLICE_NUM_HIGH; i++)
                if (!slice_high_has_vma(mm, i))
-                       ret.high_slices |= 1ul << i;
+                       __set_bit(i, ret.high_slices);
 
        return ret;
 }
@@ -150,10 +158,13 @@ static struct slice_mask slice_mask_for_size(struct mm_struct *mm, int psize)
 {
        unsigned char *hpsizes;
        int index, mask_index;
-       struct slice_mask ret = { 0, 0 };
+       struct slice_mask ret;
        unsigned long i;
        u64 lpsizes;
 
+       ret.low_slices = 0;
+       bitmap_zero(ret.high_slices, SLICE_NUM_HIGH);
+
        lpsizes = mm->context.low_slices_psize;
        for (i = 0; i < SLICE_NUM_LOW; i++)
                if (((lpsizes >> (i * 4)) & 0xf) == psize)
@@ -164,7 +175,7 @@ static struct slice_mask slice_mask_for_size(struct mm_struct *mm, int psize)
                mask_index = i & 0x1;
                index = i >> 1;
                if (((hpsizes[index] >> (mask_index * 4)) & 0xf) == psize)
-                       ret.high_slices |= 1ul << i;
+                       __set_bit(i, ret.high_slices);
        }
 
        return ret;
@@ -172,8 +183,13 @@ static struct slice_mask slice_mask_for_size(struct mm_struct *mm, int psize)
 
 static int slice_check_fit(struct slice_mask mask, struct slice_mask available)
 {
+       DECLARE_BITMAP(result, SLICE_NUM_HIGH);
+
+       bitmap_and(result, mask.high_slices,
+                  available.high_slices, SLICE_NUM_HIGH);
+
        return (mask.low_slices & available.low_slices) == mask.low_slices &&
-               (mask.high_slices & available.high_slices) == mask.high_slices;
+               bitmap_equal(result, mask.high_slices, SLICE_NUM_HIGH);
 }
 
 static void slice_flush_segments(void *parm)
@@ -220,7 +236,7 @@ static void slice_convert(struct mm_struct *mm, struct slice_mask mask, int psiz
        for (i = 0; i < SLICE_NUM_HIGH; i++) {
                mask_index = i & 0x1;
                index = i >> 1;
-               if (mask.high_slices & (1ul << i))
+               if (test_bit(i, mask.high_slices))
                        hpsizes[index] = (hpsizes[index] &
                                          ~(0xf << (mask_index * 4))) |
                                (((unsigned long)psize) << (mask_index * 4));
@@ -256,7 +272,7 @@ static bool slice_scan_available(unsigned long addr,
                slice = GET_HIGH_SLICE_INDEX(addr);
                *boundary_addr = (slice + end) ?
                        ((slice + end) << SLICE_HIGH_SHIFT) : SLICE_LOW_TOP;
-               return !!(available.high_slices & (1ul << slice));
+               return !!test_bit(slice, available.high_slices);
        }
 }
 
@@ -363,15 +379,24 @@ static unsigned long slice_find_area(struct mm_struct *mm, unsigned long len,
                return slice_find_area_bottomup(mm, len, mask, psize);
 }
 
-#define or_mask(dst, src)      do {                    \
-       (dst).low_slices |= (src).low_slices;           \
-       (dst).high_slices |= (src).high_slices;         \
-} while (0)
+static inline void slice_or_mask(struct slice_mask *dst, struct slice_mask *src)
+{
+       DECLARE_BITMAP(result, SLICE_NUM_HIGH);
 
-#define andnot_mask(dst, src)  do {                    \
-       (dst).low_slices &= ~(src).low_slices;          \
-       (dst).high_slices &= ~(src).high_slices;        \
-} while (0)
+       dst->low_slices |= src->low_slices;
+       bitmap_or(result, dst->high_slices, src->high_slices, SLICE_NUM_HIGH);
+       bitmap_copy(dst->high_slices, result, SLICE_NUM_HIGH);
+}
+
+static inline void slice_andnot_mask(struct slice_mask *dst, struct slice_mask *src)
+{
+       DECLARE_BITMAP(result, SLICE_NUM_HIGH);
+
+       dst->low_slices &= ~src->low_slices;
+
+       bitmap_andnot(result, dst->high_slices, src->high_slices, SLICE_NUM_HIGH);
+       bitmap_copy(dst->high_slices, result, SLICE_NUM_HIGH);
+}
 
 #ifdef CONFIG_PPC_64K_PAGES
 #define MMU_PAGE_BASE  MMU_PAGE_64K
@@ -383,15 +408,28 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
                                      unsigned long flags, unsigned int psize,
                                      int topdown)
 {
-       struct slice_mask mask = {0, 0};
+       struct slice_mask mask;
        struct slice_mask good_mask;
-       struct slice_mask potential_mask = {0,0} /* silence stupid warning */;
-       struct slice_mask compat_mask = {0, 0};
+       struct slice_mask potential_mask;
+       struct slice_mask compat_mask;
        int fixed = (flags & MAP_FIXED);
        int pshift = max_t(int, mmu_psize_defs[psize].shift, PAGE_SHIFT);
        struct mm_struct *mm = current->mm;
        unsigned long newaddr;
 
+       /*
+        * init different masks
+        */
+       mask.low_slices = 0;
+       bitmap_zero(mask.high_slices, SLICE_NUM_HIGH);
+
+       /* silence stupid warning */;
+       potential_mask.low_slices = 0;
+       bitmap_zero(potential_mask.high_slices, SLICE_NUM_HIGH);
+
+       compat_mask.low_slices = 0;
+       bitmap_zero(compat_mask.high_slices, SLICE_NUM_HIGH);
+
        /* Sanity checks */
        BUG_ON(mm->task_size == 0);
        VM_BUG_ON(radix_enabled());
@@ -449,7 +487,7 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
        if (psize == MMU_PAGE_64K) {
                compat_mask = slice_mask_for_size(mm, MMU_PAGE_4K);
                if (fixed)
-                       or_mask(good_mask, compat_mask);
+                       slice_or_mask(&good_mask, &compat_mask);
        }
 #endif
 
@@ -484,7 +522,7 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
         * empty and thus can be converted
         */
        potential_mask = slice_mask_for_free(mm);
-       or_mask(potential_mask, good_mask);
+       slice_or_mask(&potential_mask, &good_mask);
        slice_print_mask(" potential", potential_mask);
 
        if ((addr != 0 || fixed) && slice_check_fit(mask, potential_mask)) {
@@ -517,7 +555,7 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
 #ifdef CONFIG_PPC_64K_PAGES
        if (addr == -ENOMEM && psize == MMU_PAGE_64K) {
                /* retry the search with 4k-page slices included */
-               or_mask(potential_mask, compat_mask);
+               slice_or_mask(&potential_mask, &compat_mask);
                addr = slice_find_area(mm, len, potential_mask, psize,
                                       topdown);
        }
@@ -531,9 +569,9 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
        slice_print_mask(" mask", mask);
 
  convert:
-       andnot_mask(mask, good_mask);
-       andnot_mask(mask, compat_mask);
-       if (mask.low_slices || mask.high_slices) {
+       slice_andnot_mask(&mask, &good_mask);
+       slice_andnot_mask(&mask, &compat_mask);
+       if (mask.low_slices || !bitmap_empty(mask.high_slices, SLICE_NUM_HIGH)) {
                slice_convert(mm, mask, psize);
                if (psize > MMU_PAGE_BASE)
                        on_each_cpu(slice_flush_segments, mm, 1);
@@ -700,7 +738,7 @@ int is_hugepage_only_range(struct mm_struct *mm, unsigned long addr,
        if (psize == MMU_PAGE_64K) {
                struct slice_mask compat_mask;
                compat_mask = slice_mask_for_size(mm, MMU_PAGE_4K);
-               or_mask(available, compat_mask);
+               slice_or_mask(&available, &compat_mask);
        }
 #endif