diff --git a/configure.ac b/configure.ac
index 9ba748638..a2f3bf269 100644
--- a/configure.ac
+++ b/configure.ac
@@ -146,6 +146,8 @@ if test "x$want_kqueue" = "xyes" ; then
     fi 
 fi 
 
+AC_CHECK_HEADERS([xfs/xfs.h])
+
 
 dnl ----------------------------------------------------------------------------
 dnl
diff --git a/libtransmission/fdlimit.c b/libtransmission/fdlimit.c
index 13a0daebe..021642687 100644
--- a/libtransmission/fdlimit.c
+++ b/libtransmission/fdlimit.c
@@ -47,6 +47,10 @@
  #include <linux/falloc.h>
 #endif
 
+#ifdef HAVE_XFS_XFS_H
+ #include <xfs/xfs.h>
+#endif
+
 #include <sys/types.h>
 #include <sys/stat.h>
 #ifdef HAVE_GETRLIMIT
@@ -158,30 +162,39 @@ preallocateFileFull( const char * filename, uint64_t length )
     int fd = open( filename, flags, 0666 );
     if( fd >= 0 )
     {
-        
+# ifdef HAVE_XFS_XFS_H
+        if( !success && platform_test_xfs_fd( fd ) )
+        {
+            xfs_flock64_t fl;
+            fl.l_whence = 0;
+            fl.l_start = 0;
+            fl.l_len = length;
+            success = !xfsctl( NULL, fd, XFS_IOC_RESVSP64, &fl );
+        }
+# endif
+# ifdef SYS_DARWIN
+        if( !success )
+        {
+            fstore_t fst;
+            fst.fst_flags = F_ALLOCATECONTIG;
+            fst.fst_posmode = F_PEOFPOSMODE;
+            fst.fst_offset = 0;
+            fst.fst_length = length;
+            fst.fst_bytesalloc = 0;
+            success = !fcntl( fd, F_PREALLOCATE, &fst );
+        }
+# endif
 # ifdef HAVE_FALLOCATE
-
-        success = !fallocate( fd, FALLOC_FL_KEEP_SIZE, 0, length );
-
-# elif defined(HAVE_POSIX_FALLOCATE)
-
-        success = !posix_fallocate( fd, 0, length );
-
-# elif defined(SYS_DARWIN) 
-
-        fstore_t fst;
-        fst.fst_flags = F_ALLOCATECONTIG;
-        fst.fst_posmode = F_PEOFPOSMODE;
-        fst.fst_offset = 0;
-        fst.fst_length = length;
-        fst.fst_bytesalloc = 0;
-        success = !fcntl( fd, F_PREALLOCATE, &fst );
-
-# else
-
-        #warning no known method to preallocate files on this platform
-        success = 0;
-
+        if( !success )
+        {
+            success = !fallocate( fd, FALLOC_FL_KEEP_SIZE, 0, length );
+        }
+# endif
+# ifdef HAVE_POSIX_FALLOCATE
+        if( !success )
+        {
+            success = !posix_fallocate( fd, 0, length );
+        }
 # endif
 
         close( fd );