Merge remote-tracking branch 'remotes/amit-migration/tags/mig-2.3-1' into staging

A set of patches collected over the holidays.  Mix of optimizations and
fixes.

# gpg: Signature made Fri 16 Jan 2015 07:42:00 GMT using RSA key ID 854083B6
# gpg: Good signature from "Amit Shah <amit@amitshah.net>"
# gpg:                 aka "Amit Shah <amit@kernel.org>"
# gpg:                 aka "Amit Shah <amitshah@gmx.net>"

* remotes/amit-migration/tags/mig-2.3-1:
  vmstate: type-check sub-arrays
  migration_cancel: shutdown migration socket
  Handle bi-directional communication for fd migration
  socket shutdown
  Tests: QEMUSizedBuffer/QEMUBuffer
  QEMUSizedBuffer: only free qsb that qemu_bufopen allocated
  xbzrle: rebuild the cache_is_cached function
  xbzrle: optimize XBZRLE to decrease the cache misses

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 22 insertions, 2 deletions

diff --git a/migration/fd.c b/migration/fd.c
index d2e523af74..129da9910b 100644
--- a/migration/fd.c
+++ b/migration/fd.c
@@ -31,13 +31,29 @@
     do { } while (0)
 #endif
 
+static bool fd_is_socket(int fd)
+{
+    struct stat stat;
+    int ret = fstat(fd, &stat);
+    if (ret == -1) {
+        /* When in doubt say no */
+        return false;
+    }
+    return S_ISSOCK(stat.st_mode);
+}
+
 void fd_start_outgoing_migration(MigrationState *s, const char *fdname, Error **errp)
 {
     int fd = monitor_get_fd(cur_mon, fdname, errp);
     if (fd == -1) {
         return;
     }
-    s->file = qemu_fdopen(fd, "wb");
+
+    if (fd_is_socket(fd)) {
+        s->file = qemu_fopen_socket(fd, "wb");
+    } else {
+        s->file = qemu_fdopen(fd, "wb");
+    }
 
     migrate_fd_connect(s);
 }
@@ -58,7 +74,11 @@ void fd_start_incoming_migration(const char *infd, Error **errp)
     DPRINTF("Attempting to start an incoming migration via fd\n");
 
     fd = strtol(infd, NULL, 0);
-    f = qemu_fdopen(fd, "rb");
+    if (fd_is_socket(fd)) {
+        f = qemu_fopen_socket(fd, "rb");
+    } else {
+        f = qemu_fdopen(fd, "rb");
+    }
     if(f == NULL) {
         error_setg_errno(errp, errno, "failed to open the source descriptor");
         return;