.

bigfile/tests/test_virtmem.c

@@ -1179,7 +1179,8 @@ void test_file_access_mmapbase(void)
     RAM *ram;
     BigFileH fh_struct, *fh = &fh_struct;
     VMA vma_struct, *vma = &vma_struct;
-    Page *page0, *page2, *page3;
+//  Page *page0, *page2, *page3;
+    Page         *page2;
     size_t PS, PSb;
     int fd, err;
 

bigfile/virtmem.c

 /* Wendelin.bigfile | Virtual memory
- * Copyright (C) 2014-2015  Nexedi SA and Contributors.
+ * Copyright (C) 2014-2019  Nexedi SA and Contributors.
  *                          Kirill Smelkov <kirr@nexedi.com>
  *
  * This program is free software: you can Use, Study, Modify and Redistribute
@@ -222,9 +222,9 @@ int fileh_mmap(VMA *vma, BigFileH *fileh, pgoff_t pgoffset, pgoff_t pglen)
 {
     void *addr;
     size_t len = pglen * fileh->ramh->ram->pagesize;
-    int err = 0;
     BigFile *file = fileh->file;
     const bigfile_ops *fops = file->file_ops;
+    int err = 0;
     sigset_t save_sigset;
 
     sigsegv_block(&save_sigset);
@@ -241,13 +241,14 @@ int fileh_mmap(VMA *vma, BigFileH *fileh, pgoff_t pgoffset, pgoff_t pglen)
     vma->mmap_overlay = (fops->mmap_setup_read != NULL);
 
     if (vma->mmap_overlay) {
+        /* wcfs: mmap(base, READ) + mmap(fileh->dirty_pages) over it */
         TODO (file->blksize != fileh->ramh->ram->pagesize);
         addr = fops->mmap_setup_read(file, pgoffset, pglen, vma);
         if (!addr)
             goto fail;
         // XXX + mmap(fileh->dirty_pages)
     } else {
-        /* allocate address space somewhere */
+        /* !wcfs: allocate address space somewhere */
         addr = mem_valloc(NULL, len);
         if (!addr)
             goto fail;
@@ -407,7 +408,7 @@ int fileh_dirty_writeout(BigFileH *fileh, enum WriteoutFlags flags)
         }
 
         /* page.state -> PAGE_LOADED and correct mappings RW -> R */
-        // XXX adjust(wcfs): just remmap base file? (but it does not yet have stored changes)
+        // XXX wcfs: just remmap base file? (but it does not yet have stored changes)
         // XXX       -> vma_remove_readonly_overlay()?
         if (flags & WRITEOUT_MARKSTORED) {
             page->state = PAGE_LOADED;
@@ -452,6 +453,7 @@ void fileh_dirty_discard(BigFileH *fileh)
         BUG_ON(page->state != PAGE_DIRTY);
 
         page_drop_memory(page);
+        // XXX wcfs: remmap page(s) to base file
     }
 
     BUG_ON(!list_empty(&fileh->dirty_pages));
@@ -475,6 +477,8 @@ void fileh_invalidate_page(BigFileH *fileh, pgoff_t pgoffset)
 
     /* it's an error to invalidate fileh while writeout is in progress */
     BUG_ON(fileh->writeout_inprogress);
+    // XXX wcfs: invalidate_page must not be called (wcfs handles invalidations itself)
+    // XXX       or allow invalidate anyway (e.g. DIRTY -> base) ?
 
     page = pagemap_get(&fileh->pagemap, pgoffset);
     if (page) {