X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=lib%2Ffind_next_bit.c;h=24c59ded47a05d5617e2fe2501077f990de1ec4b;hb=725278e0ecdabbbced6f1b05a23473ec9e4cafee;hp=bda0d71a25144c110df24920b6320470e9c213a8;hpb=79072f38909e3d9883317238887460c39ddcc4cb;p=pandora-kernel.git

diff --git a/lib/find_next_bit.c b/lib/find_next_bit.c
index bda0d71a2514..24c59ded47a0 100644
--- a/lib/find_next_bit.c
+++ b/lib/find_next_bit.c
@@ -16,14 +16,12 @@
 
 #define BITOP_WORD(nr)		((nr) / BITS_PER_LONG)
 
-/**
- * find_next_bit - find the next set bit in a memory region
- * @addr: The address to base the search on
- * @offset: The bitnumber to start searching at
- * @size: The maximum size to search
+#ifdef CONFIG_GENERIC_FIND_NEXT_BIT
+/*
+ * Find the next set bit in a memory region.
  */
 unsigned long find_next_bit(const unsigned long *addr, unsigned long size,
-		unsigned long offset)
+			    unsigned long offset)
 {
 	const unsigned long *p = addr + BITOP_WORD(offset);
 	unsigned long result = offset & ~(BITS_PER_LONG-1);
@@ -60,7 +58,6 @@ found_first:
 found_middle:
 	return result + __ffs(tmp);
 }
-
 EXPORT_SYMBOL(find_next_bit);
 
 /*
@@ -68,7 +65,7 @@ EXPORT_SYMBOL(find_next_bit);
  * Linus' asm-alpha/bitops.h.
  */
 unsigned long find_next_zero_bit(const unsigned long *addr, unsigned long size,
-		unsigned long offset)
+				 unsigned long offset)
 {
 	const unsigned long *p = addr + BITOP_WORD(offset);
 	unsigned long result = offset & ~(BITS_PER_LONG-1);
@@ -105,8 +102,62 @@ found_first:
 found_middle:
 	return result + ffz(tmp);
 }
-
 EXPORT_SYMBOL(find_next_zero_bit);
+#endif /* CONFIG_GENERIC_FIND_NEXT_BIT */
+
+#ifdef CONFIG_GENERIC_FIND_FIRST_BIT
+/*
+ * Find the first set bit in a memory region.
+ */
+unsigned long find_first_bit(const unsigned long *addr, unsigned long size)
+{
+	const unsigned long *p = addr;
+	unsigned long result = 0;
+	unsigned long tmp;
+
+	while (size & ~(BITS_PER_LONG-1)) {
+		if ((tmp = *(p++)))
+			goto found;
+		result += BITS_PER_LONG;
+		size -= BITS_PER_LONG;
+	}
+	if (!size)
+		return result;
+
+	tmp = (*p) & (~0UL >> (BITS_PER_LONG - size));
+	if (tmp == 0UL)		/* Are any bits set? */
+		return result + size;	/* Nope. */
+found:
+	return result + __ffs(tmp);
+}
+EXPORT_SYMBOL(find_first_bit);
+
+/*
+ * Find the first cleared bit in a memory region.
+ */
+unsigned long find_first_zero_bit(const unsigned long *addr, unsigned long size)
+{
+	const unsigned long *p = addr;
+	unsigned long result = 0;
+	unsigned long tmp;
+
+	while (size & ~(BITS_PER_LONG-1)) {
+		if (~(tmp = *(p++)))
+			goto found;
+		result += BITS_PER_LONG;
+		size -= BITS_PER_LONG;
+	}
+	if (!size)
+		return result;
+
+	tmp = (*p) | (~0UL << size);
+	if (tmp == ~0UL)	/* Are any bits zero? */
+		return result + size;	/* Nope. */
+found:
+	return result + ffz(tmp);
+}
+EXPORT_SYMBOL(find_first_zero_bit);
+#endif /* CONFIG_GENERIC_FIND_FIRST_BIT */
 
 #ifdef __BIG_ENDIAN
 
@@ -178,4 +229,47 @@ found_middle_swap:
 
 EXPORT_SYMBOL(generic_find_next_zero_le_bit);
 
+unsigned long generic_find_next_le_bit(const unsigned long *addr, unsigned
+		long size, unsigned long offset)
+{
+	const unsigned long *p = addr + BITOP_WORD(offset);
+	unsigned long result = offset & ~(BITS_PER_LONG - 1);
+	unsigned long tmp;
+
+	if (offset >= size)
+		return size;
+	size -= result;
+	offset &= (BITS_PER_LONG - 1UL);
+	if (offset) {
+		tmp = ext2_swabp(p++);
+		tmp &= (~0UL << offset);
+		if (size < BITS_PER_LONG)
+			goto found_first;
+		if (tmp)
+			goto found_middle;
+		size -= BITS_PER_LONG;
+		result += BITS_PER_LONG;
+	}
+
+	while (size & ~(BITS_PER_LONG - 1)) {
+		tmp = *(p++);
+		if (tmp)
+			goto found_middle_swap;
+		result += BITS_PER_LONG;
+		size -= BITS_PER_LONG;
+	}
+	if (!size)
+		return result;
+	tmp = ext2_swabp(p);
+found_first:
+	tmp &= (~0UL >> (BITS_PER_LONG - size));
+	if (tmp == 0UL)		/* Are any bits set? */
+		return result + size; /* Nope. */
+found_middle:
+	return result + __ffs(tmp);
+
+found_middle_swap:
+	return result + __ffs(ext2_swab(tmp));
+}
+EXPORT_SYMBOL(generic_find_next_le_bit);
 #endif /* __BIG_ENDIAN */