.

bigfile/file_zodb.cpp

@@ -66,10 +66,13 @@ static int zfile_remmap_blk_read(VMA *vma, BigFile *file, blk_t blk) {
 
 static void zfile_munmap(VMA *vma, BigFile *file) {
     error err;
+    wcfs::_Mapping *mmap = static_cast<wcfs::_Mapping*>(vma->mmap_overlay_server);
 
+#if 0
     // NOTE taking 1 ref back from vma->mmap_overlay_server
     wcfs::Mapping mmap = adoptref(static_cast<wcfs::_Mapping*>(vma->mmap_overlay_server));
     vma->mmap_overlay_server = NULL;
+#endif
 
     err = mmap->unmap();
     if (err != nil)

wcfs/client/wcfs.cpp

@@ -259,7 +259,7 @@ error _Conn::__pin1(PinReq *req) {
         bool do_pin= true;
         error err;
         if (mmap->vma != nil) {
-            mmap->assertVMAOk();
+            mmap->_assertVMAOk();
             virt_lock();
             BigFileH *virt_fileh = mmap->vma->fileh;
             TODO (mmap->fileh->blksize != virt_fileh->ramh->ram->pagesize);
@@ -460,7 +460,7 @@ pair<Mapping, error> _FileH::mmap(int64_t blk_start, int64_t blk_len, VMA *vma)
         vma->mmap_overlay_server = mmap._ptr();
         vma->addr_start = (uintptr_t)mmap->mem_start;
         vma->addr_stop  = (uintptr_t)mmap->mem_stop;
-        mmap.assertVMAOk(); // just in case
+        mmap->_assertVMAOk(); // just in case
     }
 
     f._mmaps.push_back(mmap);   // TODO keep f._mmaps ↑blk_start
@@ -472,7 +472,9 @@ pair<Mapping, error> _FileH::mmap(int64_t blk_start, int64_t blk_len, VMA *vma)
 // unmap releases mapping memory from address space.
 //
 // After call to unmap the mapping must no longer be used.
-// virtmem calls unmap when VMA is unmapped.
+//
+// virtmem calls unmap when VMA is unmapped, thus
+// unmap must be called under virtmem lock for mappings associated with a VMA.
 error _Mapping::unmap() {
     Mapping mmap = newref(this);    // XXX newref for std::remove
     FileH f = mmap->fileh;
@@ -483,12 +485,13 @@ error _Mapping::unmap() {
     // XXX make sure mmap cannot be XXX
 
     if (mmap->vma != nil) {
-        // must be called under virtmem lock fo virtmem-intergrated case (?)
-        mmap->assertVMAOk();
+        mmap->_assertVMAOk();
         VMA *vma = mmap->vma;
-        vma->mmap_overlay_server = NULL;
+        vma->mmap_overlay_server = nil;
+        mmap->decref(); // vma->mmap_overlay_server was holding a ref to mmap
         vma->addr_start = 0;
         vma->addr_stop  = 0;
+        mmap->vma = nil;
     }
 
     error err = mm::unmap(mmap->mem_start, mmap->mem_stop - mmap->mem_start);
@@ -736,18 +739,19 @@ void _Mapping::decref() {
         delete this;
 }
 
-// assertVMAOk() verifies that mmap and vma are related to each other and cover
+// _assertVMAOk() verifies that mmap and vma are related to each other and cover
 // exactly the same virtual memory rane.
 //
 // It panics if mmap and vma do not exactly relate to each other or cover
 // different virtual memory range.
-void _Mapping::assertVMAOk() {
+void _Mapping::_assertVMAOk() {
     _Mapping* mmap = this;
-    VMA *vma = mmap.vma;
+    VMA *vma = mmap->vma;
 
-    if (!(vma->mmap_overlay_server == mmap._ptr()))
+    if (!(vma->mmap_overlay_server == static_cast<void*>(mmap)))
         panic("BUG: mmap and vma do not link to each other");
-    if (!(vma->addr_start == mmap->mem_start && vma->addr_stop == mmap->mem_stop))
+    if (!(vma->addr_start == uintptr_t(mmap->mem_start) &&
+          vma->addr_stop  == uintptr_t(mmap->mem_stop)))
         panic("BUG: mmap and vma cover different virtual memory ranges");
 
     // verified ok

wcfs/client/wcfs.h

@@ -262,6 +262,7 @@ struct _Mapping : object {
         return blk_start + (mem_stop - mem_start) / fileh->blksize;
     }
 
+    void  _assertVMAOk();
     error _remmapblk(int64_t blk, zodb::Tid at);
     error remmap_blk(int64_t blk); // for virtmem-only
     error unmap();