1 files changed, 47 insertions, 2 deletions

diff --git a/hw/9pfs/virtio-9p.c b/hw/9pfs/virtio-9p.c
index 1b2fc5dfb6..36a862f1f1 100644
--- a/hw/9pfs/virtio-9p.c
+++ b/hw/9pfs/virtio-9p.c
@@ -23,6 +23,7 @@
 #include "virtio-9p-xattr.h"
 #include "virtio-9p-coth.h"
 #include "trace.h"
+#include "migration.h"
 
 int open_fd_hw;
 int total_open_fd;
@@ -373,6 +374,19 @@ static void put_fid(V9fsPDU *pdu, V9fsFidState *fidp)
      * Don't free the fid if it is in reclaim list
      */
     if (!fidp->ref && fidp->clunked) {
+        if (fidp->fid == pdu->s->root_fid) {
+            /*
+             * if the clunked fid is root fid then we
+             * have unmounted the fs on the client side.
+             * delete the migration blocker. Ideally, this
+             * should be hooked to transport close notification
+             */
+            if (pdu->s->migration_blocker) {
+                migrate_del_blocker(pdu->s->migration_blocker);
+                error_free(pdu->s->migration_blocker);
+                pdu->s->migration_blocker = NULL;
+            }
+        }
         free_fid(pdu, fidp);
     }
 }
@@ -509,6 +523,30 @@ static int v9fs_mark_fids_unreclaim(V9fsPDU *pdu, V9fsPath *path)
     return 0;
 }
 
+static void virtfs_reset(V9fsPDU *pdu)
+{
+    V9fsState *s = pdu->s;
+    V9fsFidState *fidp = NULL;
+
+    /* Free all fids */
+    while (s->fid_list) {
+        fidp = s->fid_list;
+        s->fid_list = fidp->next;
+
+        if (fidp->ref) {
+            fidp->clunked = 1;
+        } else {
+            free_fid(pdu, fidp);
+        }
+    }
+    if (fidp) {
+        /* One or more unclunked fids found... */
+        error_report("9pfs:%s: One or more uncluncked fids "
+                     "found during reset", __func__);
+    }
+    return;
+}
+
 #define P9_QID_TYPE_DIR         0x80
 #define P9_QID_TYPE_SYMLINK     0x02
 
@@ -1182,6 +1220,8 @@ static void v9fs_version(void *opaque)
     pdu_unmarshal(pdu, offset, "ds", &s->msize, &version);
     trace_v9fs_version(pdu->tag, pdu->id, s->msize, version.data);
 
+    virtfs_reset(pdu);
+
     if (!strcmp(version.data, "9P2000.u")) {
         s->proto_version = V9FS_PROTO_2000U;
     } else if (!strcmp(version.data, "9P2000.L")) {
@@ -1235,6 +1275,11 @@ static void v9fs_attach(void *opaque)
     err = offset;
     trace_v9fs_attach_return(pdu->tag, pdu->id,
                              qid.type, qid.version, qid.path);
+    s->root_fid = fid;
+    /* disable migration */
+    error_set(&s->migration_blocker, QERR_VIRTFS_FEATURE_BLOCKS_MIGRATION,
+              s->ctx.fs_root, s->tag);
+    migrate_add_blocker(s->migration_blocker);
 out:
     put_fid(pdu, fidp);
 out_nofid:
@@ -1447,7 +1492,7 @@ static void v9fs_walk(void *opaque)
     int32_t fid, newfid;
     V9fsString *wnames = NULL;
     V9fsFidState *fidp;
-    V9fsFidState *newfidp = NULL;;
+    V9fsFidState *newfidp = NULL;
     V9fsPDU *pdu = opaque;
     V9fsState *s = pdu->s;
 
@@ -2353,7 +2398,7 @@ static void v9fs_link(void *opaque)
     V9fsState *s = pdu->s;
     int32_t dfid, oldfid;
     V9fsFidState *dfidp, *oldfidp;
-    V9fsString name;;
+    V9fsString name;
     size_t offset = 7;
     int err = 0;