.

wcfs/client/wcfs.cpp

@@ -52,8 +52,17 @@
 // server. The requests are sent to tell wcfs that client wants to observe a
 // particular bigfile as of particular revision, or stop watching for it.
 //
+// XXX mmap zeros after .headfsize
+//     (mmap-in zeros after f.size (else access to memory after file.size will raise SIGBUS))
+//     (assumes head/f size ↑=)
 //
-// Every FileH  maintains
+// Every FileH maintains
+//
+// XXX fh.headfsize - refreshed at txn boundary; assumed to be ^ ;
+// XXX fh.pinned
+//   used on:
+//      - FileH.mmap (create new mapping)
+//      - Mapping.remmap_blk (call from virtmem after RW -> RO)
 //
 //
 //
@@ -559,7 +568,6 @@ error _FileH::close() {
 }
 
 // resync resyncs connection and its file mappings onto different database view.
-// XXX place=? -> closer to pinner & connect
 error _Conn::resync(zodb::Tid at) {
     _Conn& wconn = *this;
     error err;
@@ -927,7 +935,7 @@ tuple<os::File, error> WCFS::_open(const string &path, int flags) {
 
 // ---- misc ----
 
-// mmap_zero_into_ro mmaps read-only zeros into [addr +size) so that region as all zeros.
+// mmap_zero_into_ro mmaps read-only zeros into [addr +size) so that region is all zeros.
 // created mapping, even after it is accessed, does not consume memory.
 static error mmap_zero_into_ro(void *addr, size_t size) {
     xerr::Contextf E("mmap zero");