.

bigfile/virtmem.c

@@ -471,8 +471,8 @@ void fileh_dirty_discard(BigFileH *fileh)
         BUG_ON(page->state != PAGE_DIRTY);
 
         fprintf(stderr, "discard p%ld\n", page->f_pgoffset);
+        pagemap_del(&fileh->pagemap, page->f_pgoffset);
         page_drop_memory(page);
-
         page_del(page);
         // XXX wcfs: remmap page(s) to base file
     }
@@ -515,6 +515,8 @@ void fileh_invalidate_page(BigFileH *fileh, pgoff_t pgoffset)
         /* else we just make sure to drop page memory */
         else {
             page_drop_memory(page);
+            // XXX + page_del       ?
+            // XXX + pagemap_del    ?
         }
     }
 
@@ -774,6 +776,7 @@ VMFaultResult vma_on_pagefault(VMA *vma, uintptr_t addr, int write)
         if (page->state == PAGE_LOADING_INVALIDATED) {
             page_drop_memory(page);
             page_del(page);
+            // XXX + pagemap_del    ?
 //            list_del(&page->lru);
 //            bzero(page, sizeof(*page)); /* just in case */
 //            free(page);
@@ -880,6 +883,7 @@ static int __ram_reclaim(RAM *ram)
         }
 
         /* PAGE_EMPTY pages without mappers go away */
+        // XXX merge vvv with ^^^ : page_drop_memory + pagemap_del + page_del
         if (page->state == PAGE_EMPTY) {
             BUG_ON(page->refcnt != 0);  // XXX what for then we have refcnt? -> vs discard
 
@@ -945,6 +949,7 @@ void *page_mmap(Page *page, void *addr, int prot)
 }
 
 
+// XXX -> page_drop = drop memory, delete page from pagemap, delete page
 static void page_drop_memory(Page *page)
 {
     /* Memory for this page goes out. 1) unmap it from all mmaps */
@@ -973,8 +978,14 @@ static void page_drop_memory(Page *page)
     // XXX touch lru?
 }
 
-/* page_del deletes Page struct (but not page memory - see page_drop_memory). */
+/* page_del deletes Page struct (but not page memory - see page_drop_memory).
+ *
+ * The page is removed from ram->lru.
+ */
 static void page_del(Page *page) {
+    BUG_ON(page->refcnt != 0);
+    BUG_ON(page->state == PAGE_DIRTY);  // XXX + PAGE_LOADING ?
+
     list_del(&page->lru);
     bzero(page, sizeof(*page)); /* just in case */
     free(page);

wcfs/wcfs_test.py

@@ -1786,7 +1786,7 @@ def test_wcfs_watch_vs_access():
 
 # verify that on pin message, while under pagefault, we can mmap @at/f[blk]
 # into where head/f[blk] was mmaped; the result of original pagefaulting read
-# must be from newly insterted mapping.
+# must be from newly inserted mapping.
 #
 # TODO same with two mappings to the same file, but only one changing blk mmap
 #      -> one read gets changed data, one read gets data from @head.