From 97848c10f9f8a8ce4296b149d06cab424eba05b3 Mon Sep 17 00:00:00 2001
From: Yury Norov <yury.norov@gmail.com>
Date: Sat, 17 Sep 2022 20:07:15 -0700
Subject: [PATCH] lib/bitmap: remove bitmap_ord_to_pos

Now that we have find_nth_bit(), we can drop bitmap_ord_to_pos().

Signed-off-by: Yury Norov <yury.norov@gmail.com>
---
 include/linux/bitmap.h   |  1 -
 include/linux/nodemask.h |  3 +--
 lib/bitmap.c             | 36 +++---------------------------------
 3 files changed, 4 insertions(+), 36 deletions(-)

diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h
index b2aef45af0db..7d6d73b78147 100644
--- a/include/linux/bitmap.h
+++ b/include/linux/bitmap.h
@@ -225,7 +225,6 @@ void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int n
 #else
 #define bitmap_copy_le bitmap_copy
 #endif
-unsigned int bitmap_ord_to_pos(const unsigned long *bitmap, unsigned int ord, unsigned int nbits);
 int bitmap_print_to_pagebuf(bool list, char *buf,
 				   const unsigned long *maskp, int nmaskbits);
 
diff --git a/include/linux/nodemask.h b/include/linux/nodemask.h
index 4b71a96190a8..0c45fb066caa 100644
--- a/include/linux/nodemask.h
+++ b/include/linux/nodemask.h
@@ -508,8 +508,7 @@ static inline int node_random(const nodemask_t *maskp)
 
 	w = nodes_weight(*maskp);
 	if (w)
-		bit = bitmap_ord_to_pos(maskp->bits,
-			get_random_int() % w, MAX_NUMNODES);
+		bit = find_nth_bit(maskp->bits, MAX_NUMNODES, get_random_int() % w);
 	return bit;
 #else
 	return 0;
diff --git a/lib/bitmap.c b/lib/bitmap.c
index 3fc2e338ec30..1c81413c51f8 100644
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -968,36 +968,6 @@ static int bitmap_pos_to_ord(const unsigned long *buf, unsigned int pos, unsigne
 	return bitmap_weight(buf, pos);
 }
 
-/**
- * bitmap_ord_to_pos - find position of n-th set bit in bitmap
- *	@buf: pointer to bitmap
- *	@ord: ordinal bit position (n-th set bit, n >= 0)
- *	@nbits: number of valid bit positions in @buf
- *
- * Map the ordinal offset of bit @ord in @buf to its position in @buf.
- * Value of @ord should be in range 0 <= @ord < weight(buf). If @ord
- * >= weight(buf), returns @nbits.
- *
- * If for example, just bits 4 through 7 are set in @buf, then @ord
- * values 0 through 3 will get mapped to 4 through 7, respectively,
- * and all other @ord values returns @nbits.  When @ord value 3
- * gets mapped to (returns) @pos value 7 in this example, that means
- * that the 3rd set bit (starting with 0th) is at position 7 in @buf.
- *
- * The bit positions 0 through @nbits-1 are valid positions in @buf.
- */
-unsigned int bitmap_ord_to_pos(const unsigned long *buf, unsigned int ord, unsigned int nbits)
-{
-	unsigned int pos;
-
-	for (pos = find_first_bit(buf, nbits);
-	     pos < nbits && ord;
-	     pos = find_next_bit(buf, nbits, pos + 1))
-		ord--;
-
-	return pos;
-}
-
 /**
  * bitmap_remap - Apply map defined by a pair of bitmaps to another bitmap
  *	@dst: remapped result
@@ -1047,7 +1017,7 @@ void bitmap_remap(unsigned long *dst, const unsigned long *src,
 		if (n < 0 || w == 0)
 			set_bit(oldbit, dst);	/* identity map */
 		else
-			set_bit(bitmap_ord_to_pos(new, n % w, nbits), dst);
+			set_bit(find_nth_bit(new, nbits, n % w), dst);
 	}
 }
 EXPORT_SYMBOL(bitmap_remap);
@@ -1086,7 +1056,7 @@ int bitmap_bitremap(int oldbit, const unsigned long *old,
 	if (n < 0 || w == 0)
 		return oldbit;
 	else
-		return bitmap_ord_to_pos(new, n % w, bits);
+		return find_nth_bit(new, bits, n % w);
 }
 EXPORT_SYMBOL(bitmap_bitremap);
 
@@ -1210,7 +1180,7 @@ void bitmap_onto(unsigned long *dst, const unsigned long *orig,
 	 * The following code is a more efficient, but less
 	 * obvious, equivalent to the loop:
 	 *	for (m = 0; m < bitmap_weight(relmap, bits); m++) {
-	 *		n = bitmap_ord_to_pos(orig, m, bits);
+	 *		n = find_nth_bit(orig, bits, m);
 	 *		if (test_bit(m, orig))
 	 *			set_bit(n, dst);
 	 *	}