+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/bitops.h>
+#include <asm/unaligned.h>
+
+#include "varint.h"
+
+int bch2_varint_encode(u8 *out, u64 v)
+{
+ unsigned bits = fls64(v|1);
+ unsigned bytes = DIV_ROUND_UP(bits, 7);
+
+ if (likely(bytes < 9)) {
+ v <<= bytes;
+ v |= ~(~0 << (bytes - 1));
+ } else {
+ *out++ = 255;
+ bytes = 9;
+ }
+
+ put_unaligned_le64(v, out);
+ return bytes;
+}
+
+int bch2_varint_decode(const u8 *in, const u8 *end, u64 *out)
+{
+ u64 v = get_unaligned_le64(in);
+ unsigned bytes = ffz(v & 255) + 1;
+
+ if (unlikely(in + bytes > end))
+ return -1;
+
+ if (likely(bytes < 9)) {
+ v >>= bytes;
+ v &= ~(~0ULL << (7 * bytes));
+ } else {
+ v = get_unaligned_le64(++in);
+ }
+
+ *out = v;
+ return bytes;
+}