diff --git a/src/os/bluestore/BlueFS.cc b/src/os/bluestore/BlueFS.cc
index d8587c8d2cb..3c5a605eb28 100644
--- a/src/os/bluestore/BlueFS.cc
+++ b/src/os/bluestore/BlueFS.cc
@@ -1354,7 +1354,7 @@ void BlueFS::_drop_link(FileRef file)
 int BlueFS::_read_random(
   FileReader *h,         ///< [in] read from here
   uint64_t off,          ///< [in] offset
-  size_t len,            ///< [in] this many bytes
+  uint64_t len,          ///< [in] this many bytes
   char *out)             ///< [out] optional: or copy it here
 {
   auto* buf = &h->buf;
@@ -1384,7 +1384,7 @@ int BlueFS::_read_random(
       s_lock.unlock();
       uint64_t x_off = 0;
       auto p = h->file->fnode.seek(off, &x_off);
-      uint64_t l = std::min(p->length - x_off, static_cast<uint64_t>(len));
+      uint64_t l = std::min(p->length - x_off, len);
       dout(20) << __func__ << " read random 0x"
 	       << std::hex << x_off << "~" << l << std::dec
 	       << " of " << *p << dendl;
diff --git a/src/os/bluestore/BlueFS.h b/src/os/bluestore/BlueFS.h
index 780b3d2475a..c0b47956135 100644
--- a/src/os/bluestore/BlueFS.h
+++ b/src/os/bluestore/BlueFS.h
@@ -375,7 +375,7 @@ private:
   int _read_random(
     FileReader *h,   ///< [in] read from here
     uint64_t offset, ///< [in] offset
-    size_t len,      ///< [in] this many bytes
+    uint64_t len,    ///< [in] this many bytes
     char *out);      ///< [out] optional: or copy it here
 
   void _invalidate_cache(FileRef f, uint64_t offset, uint64_t length);
diff --git a/src/osd/osd_types.h b/src/osd/osd_types.h
index a9426df8ad1..326f270ec5f 100644
--- a/src/osd/osd_types.h
+++ b/src/osd/osd_types.h
@@ -4160,7 +4160,7 @@ public:
     return head.version == 0 && head.epoch == 0;
   }
 
-  size_t approx_size() const {
+  uint64_t approx_size() const {
     return head.version - tail.version;
   }
 
diff --git a/src/osdc/Striper.cc b/src/osdc/Striper.cc
index 5c5b4cb7d72..e8232f125c1 100644
--- a/src/osdc/Striper.cc
+++ b/src/osdc/Striper.cc
@@ -406,7 +406,7 @@ void Striper::StripedReadResult::add_partial_sparse_result(
 
     ceph_assert(s->first <= *bl_off);
     size_t left = (s->first + s->second) - *bl_off;
-    size_t actual = std::min(left, tlen);
+    size_t actual = std::min<size_t>(left, tlen);
 
     if (actual > 0) {
       ldout(cct, 20) << "  s has " << actual << ", copying" << dendl;