hw/block: Request permissions

This makes all device emulations with a qdev drive property request
permissions on their BlockBackend. The only thing we block at this point
is resizing images for some devices that can't support it.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>

1 files changed, 21 insertions, 1 deletions

diff --git a/hw/block/block.c b/hw/block/block.c
index 8dc9d84a39..7059ba1420 100644
--- a/hw/block/block.c
+++ b/hw/block/block.c
@@ -51,11 +51,31 @@ void blkconf_blocksizes(BlockConf *conf)
     }
 }
 
-void blkconf_apply_backend_options(BlockConf *conf)
+void blkconf_apply_backend_options(BlockConf *conf, bool readonly,
+                                   bool resizable, Error **errp)
 {
     BlockBackend *blk = conf->blk;
     BlockdevOnError rerror, werror;
+    uint64_t perm, shared_perm;
     bool wce;
+    int ret;
+
+    perm = BLK_PERM_CONSISTENT_READ;
+    if (!readonly) {
+        perm |= BLK_PERM_WRITE;
+    }
+
+    /* TODO Remove BLK_PERM_WRITE unless explicitly configured so */
+    shared_perm = BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE_UNCHANGED |
+                  BLK_PERM_GRAPH_MOD | BLK_PERM_WRITE;
+    if (resizable) {
+        shared_perm |= BLK_PERM_RESIZE;
+    }
+
+    ret = blk_set_perm(blk, perm, shared_perm, errp);
+    if (ret < 0) {
+        return;
+    }
 
     switch (conf->wce) {
     case ON_OFF_AUTO_ON:    wce = true; break;