diff --git a/src/opr/Makefile.in b/src/opr/Makefile.in
index af6a61b1c0..647eaca926 100644
--- a/src/opr/Makefile.in
+++ b/src/opr/Makefile.in
@@ -9,6 +9,7 @@ LT_libs = $(LIB_hcrypto) $(LIB_roken)
 HEADERS = $(TOP_INCDIR)/afs/opr.h \
 	  $(TOP_INCDIR)/afs/opr_assert.h \
 	  $(TOP_INCDIR)/opr/dict.h \
+	  $(TOP_INCDIR)/opr/ffs.h \
 	  $(TOP_INCDIR)/opr/fmt.h \
 	  $(TOP_INCDIR)/opr/jhash.h \
 	  $(TOP_INCDIR)/opr/lock.h \
@@ -45,6 +46,9 @@ $(TOP_INCDIR)/afs/opr_assert.h: ${srcdir}/opr_assert.h
 $(TOP_INCDIR)/opr/dict.h: ${srcdir}/dict.h
 	$(INSTALL_DATA) $? $@
 
+$(TOP_INCDIR)/opr/ffs.h: ${srcdir}/ffs.h
+	$(INSTALL_DATA) $? $@
+
 $(TOP_INCDIR)/opr/fmt.h: ${srcdir}/fmt.h
 	$(INSTALL_DATA) $? $@
 
diff --git a/src/opr/NTMakefile b/src/opr/NTMakefile
index 7f49d3bbc8..127c407965 100644
--- a/src/opr/NTMakefile
+++ b/src/opr/NTMakefile
@@ -14,6 +14,7 @@ INCFILES = \
 	$(INCFILEDIR)\opr.h \
 	$(INCFILEDIR)\opr_assert.h \
 	$(DESTDIR)\include\opr\dict.h \
+	$(DESTDIR)\include\opr\ffs.h \
 	$(DESTDIR)\include\opr\fmt.h \
 	$(DESTDIR)\include\opr\jhash.h \
 	$(DESTDIR)\include\opr\proc.h \
diff --git a/src/opr/ffs.h b/src/opr/ffs.h
new file mode 100644
index 0000000000..9a9ff6e480
--- /dev/null
+++ b/src/opr/ffs.h
@@ -0,0 +1,117 @@
+/*
+ * Copyright (C) 2014 by the Massachusetts Institute of Technology.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ * * Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in
+ *   the documentation and/or other materials provided with the
+ *   distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/*
+ * This contains portable implementations of the BSD ffs() suite of functions,
+ * which locate the first or last bit set in a bit string.
+ */
+
+#ifndef OPENAFS_OPR_FFS_H
+#define OPENAFS_OPR_FFS_H
+
+static_inline int
+opr_ffs(int value)
+{
+    afs_int32 i;
+    afs_uint32 tmp = value;
+
+    if (tmp == 0)
+	return 0;
+    /* This loop must terminate because tmp is nonzero and thus has at least
+     * one bit set. */
+    for (i = 1;; ++i) {
+	if (tmp & 1u)
+	    return i;
+	else
+	    tmp >>= 1;
+    }
+    /* NOTREACHED */
+}
+
+static_inline int
+opr_ffsll(long long value)
+{
+    afs_int32 i;
+    afs_uint64 tmp = value;
+
+    if (tmp == 0)
+	return 0;
+    /* This loop must terminate because tmp is nonzero and thus has at least
+     * one bit set. */
+    for (i = 1;; ++i) {
+	if (tmp & 1ull)
+	    return i;
+	else
+	    tmp >>= 1;
+    }
+    /* NOTREACHED */
+}
+
+static_inline int
+opr_fls(int value)
+{
+    afs_int32 i;
+    /* tmp must be unsigned to avoid undefined behavior. */
+    afs_uint32 tmp = value;
+
+    if (tmp == 0)
+	return 0;
+    /* This loop must terminate because tmp is nonzero and thus has at least
+     * one bit set. */
+    for (i = 32;; --i) {
+	if (tmp & 0x80000000u)
+	    return i;
+	else
+	    tmp <<= 1;
+    }
+    /* NOTREACHED */
+}
+
+static_inline int
+opr_flsll(long long value)
+{
+    afs_int32 i;
+    /* tmp must be unsigned to avoid undefined behavior. */
+    afs_uint64 tmp = value;
+
+    if (tmp == 0)
+	return 0;
+    /* This loop must terminate because tmp is nonzero and thus has at least
+     * one bit set. */
+    for (i = 64;; --i) {
+	if (tmp & 0x8000000000000000ull)
+	    return i;
+	else
+	    tmp <<= 1;
+    }
+    /* NOTREACHED */
+}
+
+#endif /* OPENAFS_OPR_FFS_H */