.

bigfile/tests/test_virtmem.c

@@ -1180,7 +1180,7 @@ void test_file_access_mmapbase(void)
     BigFileH fh_struct, *fh = &fh_struct;
     VMA vma_struct, *vma = &vma_struct;
 //  Page *page0, *page2, *page3;
-    Page         *page2;
+    Page *page0, *page2;
     size_t PS, PSb;
     int fd, err;
 
@@ -1291,6 +1291,23 @@ void test_file_access_mmapbase(void)
 
     ok1(ram->lru_list.prev == &page2->lru);
     ok1(page2->lru.prev == &ram->lru_list);
+
+    /* write to page[0] - page COW'ed into RAM */
+    B(vma, 0*PSb) = 10;
+
+    page0 = pagemap_get(&fh->pagemap, 100);
+    ok1( M(vma, 0));    CHECK_PAGE  (page0,   100,    PAGE_DIRTY,     1);
+    ok1(!M(vma, 1));    CHECK_NOPAGE(         101                      );
+    ok1( M(vma, 2));    CHECK_PAGE  (page2,   102,    PAGE_DIRTY,     1);
+    ok1(!M(vma, 3));    CHECK_NOPAGE(         103                      );
+
+    ok1(B(vma, 0*PSb + 0) ==  10); /* set by write */
+    ok1(B(vma, 0*PSb + 1) == 100);
+    ok1(B(vma, 0*PSb + PSb - 1) == 100);
+
+    ok1(ram->lru_list.prev == &page0->lru);
+    ok1(page0->lru.prev == &page2->lru);
+    ok1(page2->lru.prev == &ram->lru_list);
 }