m68k: Add ext2_find_{first,next}_bit() for ext4

Add ext2_find_{first,next}_bit(), which are needed for ext4.  They're
derived out of the ext2_find_next_zero_bit found in the same file.
Compile tested with crosstools

[Reworked to preserve all symmetry with ext2_find_{first,next}_zero_bit()]

This fixes http://bugzilla.kernel.org/show_bug.cgi?id=10393

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 43 insertions, 2 deletions

diff --git a/include/asm-m68k/bitops.h b/include/asm-m68k/bitops.h
index 83d1f286230..3e8106442d5 100644
--- a/include/asm-m68k/bitops.h
+++ b/include/asm-m68k/bitops.h
@@ -410,8 +410,49 @@ static inline int ext2_find_next_zero_bit(const void *vaddr, unsigned size,
         res = ext2_find_first_zero_bit (p, size - 32 * (p - addr));
         return (p - addr) * 32 + res;
 }
-#define ext2_find_next_bit(addr, size, off) \
-        generic_find_next_le_bit((unsigned long *)(addr), (size), (off))
+
+static inline int ext2_find_first_bit(const void *vaddr, unsigned size)
+{
+        const unsigned long *p = vaddr, *addr = vaddr;
+        int res;
+
+        if (!size)
+                return 0;
+
+        size = (size >> 5) + ((size & 31) > 0);
+        while (*p++ == 0UL) {
+                if (--size == 0)
+                        return (p - addr) << 5;
+        }
+
+        --p;
+        for (res = 0; res < 32; res++)
+                if (ext2_test_bit(res, p))
+                        break;
+        return (p - addr) * 32 + res;
+}
+
+static inline int ext2_find_next_bit(const void *vaddr, unsigned size,
+                                     unsigned offset)
+{
+        const unsigned long *addr = vaddr;
+        const unsigned long *p = addr + (offset >> 5);
+        int bit = offset & 31UL, res;
+
+        if (offset >= size)
+                return size;
+
+        if (bit) {
+                /* Look for one in first longword */
+                for (res = bit; res < 32; res++)
+                        if (ext2_test_bit(res, p))
+                                return (p - addr) * 32 + res;
+                p++;
+        }
+        /* No set bit yet, search remaining full bytes for a set bit */
+        res = ext2_find_first_bit(p, size - 32 * (p - addr));
+        return (p - addr) * 32 + res;
+}
 
 #endif /* __KERNEL__ */