file-posix: Fix bdrv_open_flags() for snapshot=on

[qemu.git] / block.c

diff --git a/block.c b/block.c
index ccf008c177c87549bfe9b71fa585d003559f924c..33804cdcaac0d43efe6c2cd36088cff0ec66f4cb 100644 (file)
--- a/block.c
+++ b/block.c
@@ -1163,13 +1163,6 @@ static int bdrv_open_flags(BlockDriverState *bs, int flags)
      */
     open_flags &= ~(BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING | BDRV_O_PROTOCOL);
 
-    /*
-     * Snapshots should be writable.
-     */
-    if (flags & BDRV_O_TEMPORARY) {
-        open_flags |= BDRV_O_RDWR;
-    }
-
     return open_flags;
 }
 
@@ -1698,6 +1691,7 @@ static void bdrv_child_set_perm(BdrvChild *c, uint64_t perm, uint64_t shared);
 
 typedef struct BlockReopenQueueEntry {
      bool prepared;
+     bool perms_checked;
      BDRVReopenState state;
      QSIMPLEQ_ENTRY(BlockReopenQueueEntry) entry;
 } BlockReopenQueueEntry;
@@ -3155,19 +3149,27 @@ int bdrv_reopen_multiple(AioContext *ctx, BlockReopenQueue *bs_queue, Error **er
 {
     int ret = -1;
     BlockReopenQueueEntry *bs_entry, *next;
-    Error *local_err = NULL;
 
     assert(bs_queue != NULL);
 
     QSIMPLEQ_FOREACH(bs_entry, bs_queue, entry) {
         assert(bs_entry->state.bs->quiesce_counter > 0);
-        if (bdrv_reopen_prepare(&bs_entry->state, bs_queue, &local_err)) {
-            error_propagate(errp, local_err);
+        if (bdrv_reopen_prepare(&bs_entry->state, bs_queue, errp)) {
             goto cleanup;
         }
         bs_entry->prepared = true;
     }
 
+    QSIMPLEQ_FOREACH(bs_entry, bs_queue, entry) {
+        BDRVReopenState *state = &bs_entry->state;
+        ret = bdrv_check_perm(state->bs, bs_queue, state->perm,
+                              state->shared_perm, NULL, errp);
+        if (ret < 0) {
+            goto cleanup_perm;
+        }
+        bs_entry->perms_checked = true;
+    }
+
     /* If we reach this point, we have success and just need to apply the
      * changes
      */
@@ -3176,7 +3178,20 @@ int bdrv_reopen_multiple(AioContext *ctx, BlockReopenQueue *bs_queue, Error **er
     }
 
     ret = 0;
+cleanup_perm:
+    QSIMPLEQ_FOREACH_SAFE(bs_entry, bs_queue, entry, next) {
+        BDRVReopenState *state = &bs_entry->state;
 
+        if (!bs_entry->perms_checked) {
+            continue;
+        }
+
+        if (ret == 0) {
+            bdrv_set_perm(state->bs, state->perm, state->shared_perm);
+        } else {
+            bdrv_abort_perm_update(state->bs);
+        }
+    }
 cleanup:
     QSIMPLEQ_FOREACH_SAFE(bs_entry, bs_queue, entry, next) {
         if (ret) {
@@ -3430,12 +3445,6 @@ int bdrv_reopen_prepare(BDRVReopenState *reopen_state, BlockReopenQueue *queue,
         } while ((entry = qdict_next(reopen_state->options, entry)));
     }
 
-    ret = bdrv_check_perm(reopen_state->bs, queue, reopen_state->perm,
-                          reopen_state->shared_perm, NULL, errp);
-    if (ret < 0) {
-        goto error;
-    }
-
     ret = 0;
 
     /* Restore the original reopen_state->options QDict */
@@ -3502,9 +3511,6 @@ void bdrv_reopen_commit(BDRVReopenState *reopen_state)
 
     bdrv_refresh_limits(bs, NULL);
 
-    bdrv_set_perm(reopen_state->bs, reopen_state->perm,
-                  reopen_state->shared_perm);
-
     new_can_write =
         !bdrv_is_read_only(bs) && !(bdrv_get_flags(bs) & BDRV_O_INACTIVE);
     if (!old_can_write && new_can_write && drv->bdrv_reopen_bitmaps_rw) {
@@ -3536,8 +3542,6 @@ void bdrv_reopen_abort(BDRVReopenState *reopen_state)
     if (drv->bdrv_reopen_abort) {
         drv->bdrv_reopen_abort(reopen_state);
     }
-
-    bdrv_abort_perm_update(reopen_state->bs);
 }