.

bigfile/tests/test_virtmem.c

@@ -1560,7 +1560,7 @@ void test_file_access_mmapbase(void)
     vma_unmap(vma);
     err = fileh_mmap(vma, fh, 100, 4);
 
-    /* data saved, served from base layer */
+    /* data saved; served from base layer */
     ok1(B(vma, 0*PSb + 0) ==  10);
     ok1(B(vma, 0*PSb + 1) == 100);
     ok1(B(vma, 0*PSb + PSb - 1) == 100);

include/wendelin/bigfile/file.h

@@ -81,6 +81,10 @@ struct bigfile_ops {
      *
      * The mapping will be used as the base read-only layer for vma.
      *
+     * XXX bigfile backend owns setup mapping and can change it dynamically
+     * e.g. due to changes to the file from outside. However it should XXX
+     * check dirtyv and if dirty=1 not change that page until remmap_blk_read.
+     *
      * XXX mmap_read -> !loadblk ?
      * NOTE blk and blklen are in blocks, not pages.
      *