.

bigfile/virtmem.c

@@ -44,6 +44,7 @@ static void     page_del(Page *page);
 static void    *vma_page_addr(VMA *vma, Page *page);
 static pgoff_t  vma_addr_fpgoffset(VMA *vma, uintptr_t addr);
 static void     vma_mmap_page(VMA *vma, Page *page);
+static int      vma_page_infilerange(VMA *vma, Page *page);
 static int      vma_page_ismapped(VMA *vma, Page *page);
 static void     vma_page_ensure_unmapped(VMA *vma, Page *page);
 static void     vma_page_ensure_notmappedrw(VMA *vma, Page *page);
@@ -283,7 +284,7 @@ int fileh_mmap(VMA *vma, BigFileH *fileh, pgoff_t pgoffset, pgoff_t pglen)
             page = list_entry(hpage, typeof(*page), in_dirty);
             BUG_ON(page->state != PAGE_DIRTY);
 
-            if (!(pgoffset <= page->f_pgoffset && page->f_pgoffset < pgoffset + pglen))
+            if (!vma_page_infilerange(vma, page))
                 continue; /* page is out of requested mmap coverage */
 
             // XXX notify watcher that we mmap RAM page in its range? -> no need
@@ -889,7 +890,11 @@ VMFaultResult vma_on_pagefault(VMA *vma, uintptr_t addr, int write)
     if (fileh->mmap_overlay) {
         list_for_each(hmmap, &fileh->mmaps) {
             VMA *vma2 = list_entry(hmmap, typeof(*vma2), same_fileh);
-            if (vma2 != vma)
+            if (vma2 == vma)
+                continue;
+            if (!vma_page_infilerange(vma2, page))
+                continue; /* page is out of vma2 file-range coverage */
+
             vma_mmap_page(vma2, page);
         }
     }
@@ -1092,15 +1097,23 @@ static void vma_mmap_page(VMA *vma, Page *page) {
     }
 }
 
-/* is `page` mapped to `vma` */
-static int vma_page_ismapped(VMA *vma, Page *page)
+/* is `page->fpgoffset` belongs to file-range covered by `vma` */
+static int vma_page_infilerange(VMA *vma, Page *page)
 {
     pgoff_t vma_fpgstop;
     ASSERT(vma->fileh == page->fileh);
 
     vma_fpgstop = vma_addr_fpgoffset(vma, vma->addr_stop);
-    if (!(vma->f_pgoffset <= page->f_pgoffset  &&
-                             page->f_pgoffset < vma_fpgstop))
+    return (vma->f_pgoffset <= page->f_pgoffset  &&
+                               page->f_pgoffset < vma_fpgstop);
+}
+
+/* is `page` mapped to `vma` */
+static int vma_page_ismapped(VMA *vma, Page *page)
+{
+    ASSERT(vma->fileh == page->fileh);
+
+    if (!vma_page_infilerange(vma, page))
         return 0;
 
     return bitmap_test_bit(vma->page_ismappedv, page->f_pgoffset - vma->f_pgoffset);

wcfs/internal/wcfs_virtmem.cpp

@@ -505,17 +505,10 @@ void _Mapping::unmap() {
     FileH f = mmap->fileh;
     //f->_mmaps.remove(mmap);
 
-    printf("\nbefore remove %p:\n", mmap._ptr());
-    for (auto x : f->_mmaps)
-        printf("\t%p\n", x._ptr());
-
     // FIXME keep mmaps sorted
     f->_mmaps.erase(
         std::remove(f->_mmaps.begin(), f->_mmaps.end(), mmap),
         f->_mmaps.end());
-    printf("\nafter remove:\n");
-    for (auto x : f->_mmaps)
-        printf("\t%p\n", x._ptr());
 }