bitmap: introduce BITMAP_FROM_U64()

The macro is the compile-time analogue of bitmap_from_u64() with the same
purpose: convert the 64-bit number to the properly ordered pair of 32-bit
parts, suitable for filling the bitmap in 32-bit BE environment.

Use it to make test_bitmap_parselist() correct for 32-bit BE ABIs.

Tested on BE mips/qemu.

[akpm@linux-foundation.org: tweak code comment]
Link: http://lkml.kernel.org/r/20170810172916.24144-1-ynorov@caviumnetworks.com
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Cc: Noam Camus <noamca@mellanox.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 32 insertions, 15 deletions

diff --git a/lib/test_bitmap.c b/lib/test_bitmap.c
index 431c97fb1aa0..599c6713f2a2 100644
--- a/lib/test_bitmap.c
+++ b/lib/test_bitmap.c
@@ -175,24 +175,41 @@ struct test_bitmap_parselist{
         const int flags;
 };
 
-static const unsigned long exp[] = {1, 2, 0x0000ffff, 0xffff0000, 0x55555555,
-                                0xaaaaaaaa, 0x11111111, 0x22222222, 0xffffffff,
-                                0xfffffffe, 0x3333333311111111, 0xffffffff77777777};
-static const unsigned long exp2[] = {0x3333333311111111, 0xffffffff77777777};
+static const unsigned long exp[] __initconst = {
+        BITMAP_FROM_U64(1),
+        BITMAP_FROM_U64(2),
+        BITMAP_FROM_U64(0x0000ffff),
+        BITMAP_FROM_U64(0xffff0000),
+        BITMAP_FROM_U64(0x55555555),
+        BITMAP_FROM_U64(0xaaaaaaaa),
+        BITMAP_FROM_U64(0x11111111),
+        BITMAP_FROM_U64(0x22222222),
+        BITMAP_FROM_U64(0xffffffff),
+        BITMAP_FROM_U64(0xfffffffe),
+        BITMAP_FROM_U64(0x3333333311111111),
+        BITMAP_FROM_U64(0xffffffff77777777)
+};
+
+static const unsigned long exp2[] __initconst = {
+        BITMAP_FROM_U64(0x3333333311111111),
+        BITMAP_FROM_U64(0xffffffff77777777)
+};
 
 static const struct test_bitmap_parselist parselist_tests[] __initconst = {
+#define step (sizeof(u64) / sizeof(unsigned long))
+
         {0, "0",                        &exp[0], 8, 0},
-        {0, "1",                        &exp[1], 8, 0},
-        {0, "0-15",                     &exp[2], 32, 0},
-        {0, "16-31",                    &exp[3], 32, 0},
-        {0, "0-31:1/2",                 &exp[4], 32, 0},
-        {0, "1-31:1/2",                 &exp[5], 32, 0},
-        {0, "0-31:1/4",                 &exp[6], 32, 0},
-        {0, "1-31:1/4",                 &exp[7], 32, 0},
-        {0, "0-31:4/4",                 &exp[8], 32, 0},
-        {0, "1-31:4/4",                 &exp[9], 32, 0},
-        {0, "0-31:1/4,32-63:2/4",       &exp[10], 64, 0},
-        {0, "0-31:3/4,32-63:4/4",       &exp[11], 64, 0},
+        {0, "1",                        &exp[1 * step], 8, 0},
+        {0, "0-15",                     &exp[2 * step], 32, 0},
+        {0, "16-31",                    &exp[3 * step], 32, 0},
+        {0, "0-31:1/2",                 &exp[4 * step], 32, 0},
+        {0, "1-31:1/2",                 &exp[5 * step], 32, 0},
+        {0, "0-31:1/4",                 &exp[6 * step], 32, 0},
+        {0, "1-31:1/4",                 &exp[7 * step], 32, 0},
+        {0, "0-31:4/4",                 &exp[8 * step], 32, 0},
+        {0, "1-31:4/4",                 &exp[9 * step], 32, 0},
+        {0, "0-31:1/4,32-63:2/4",       &exp[10 * step], 64, 0},
+        {0, "0-31:3/4,32-63:4/4",       &exp[11 * step], 64, 0},
 
         {0, "0-31:1/4,32-63:2/4,64-95:3/4,96-127:4/4",  exp2, 128, 0},