diff mbox

[09/21] block: Add blk_name_taken()

Message ID 1422300468-16216-10-git-send-email-mreitz@redhat.com
State New
Headers show

Commit Message

Max Reitz Jan. 26, 2015, 7:27 p.m. UTC 
There may be BlockBackends which are not returned by blk_by_name(), but
do exist and have a name. blk_name_taken() allows testing whether a
specific name is in use already, independent of whether the BlockBackend
with that name is accessible through blk_by_name().

Signed-off-by: Max Reitz <mreitz@redhat.com>
---
 block.c                        |  2 +-
 block/block-backend.c          | 19 ++++++++++++++++++-
 include/sysemu/block-backend.h |  1 +
 3 files changed, 20 insertions(+), 2 deletions(-)

Comments

Eric Blake Jan. 29, 2015, 11:51 p.m. UTC | #1 
On 01/26/2015 12:27 PM, Max Reitz wrote:
> There may be BlockBackends which are not returned by blk_by_name(), but
> do exist and have a name. blk_name_taken() allows testing whether a
> specific name is in use already, independent of whether the BlockBackend
> with that name is accessible through blk_by_name().
> 
> Signed-off-by: Max Reitz <mreitz@redhat.com>
> ---
>  block.c                        |  2 +-
>  block/block-backend.c          | 19 ++++++++++++++++++-
>  include/sysemu/block-backend.h |  1 +
>  3 files changed, 20 insertions(+), 2 deletions(-)
> 
> diff --git a/block.c b/block.c
> index 0cd6457..8eef0c5 100644
> --- a/block.c
> +++ b/block.c
> @@ -898,7 +898,7 @@ static void bdrv_assign_node_name(BlockDriverState *bs,
>      }
>  
>      /* takes care of avoiding namespaces collisions */
> -    if (blk_by_name(node_name)) {
> +    if (blk_name_taken(node_name)) {

While you are here, s/namespaces/namespace/

Reviewed-by: Eric Blake <eblake@redhat.com>
diff mbox

Patch

diff --git a/block.c b/block.c
index 0cd6457..8eef0c5 100644
--- a/block.c
+++ b/block.c
@@ -898,7 +898,7 @@  static void bdrv_assign_node_name(BlockDriverState *bs,
     }
 
     /* takes care of avoiding namespaces collisions */
-    if (blk_by_name(node_name)) {
+    if (blk_name_taken(node_name)) {
         error_setg(errp, "node-name=%s is conflicting with a device id",
                    node_name);
         return;
diff --git a/block/block-backend.c b/block/block-backend.c
index a7264a0..4467a8c 100644
--- a/block/block-backend.c
+++ b/block/block-backend.c
@@ -84,7 +84,7 @@  BlockBackend *blk_new(const char *name, Notifier *close_all_notifier,
         error_setg(errp, "Invalid device name");
         return NULL;
     }
-    if (blk_by_name(name)) {
+    if (blk_name_taken(name)) {
         error_setg(errp, "Device with id '%s' already exists", name);
         return NULL;
     }
@@ -259,6 +259,23 @@  BlockBackend *blk_by_name(const char *name)
 }
 
 /*
+ * This function should be used to check whether a certain BlockBackend name is
+ * already taken; blk_by_name() will only search in the list of monitor-owned
+ * BlockBackends which is not necessarily complete.
+ */
+bool blk_name_taken(const char *name)
+{
+    BlockBackend *blk;
+
+    QTAILQ_FOREACH(blk, &blk_backends, link) {
+        if (!strcmp(name, blk->name)) {
+            return true;
+        }
+    }
+    return false;
+}
+
+/*
  * Return the BlockDriverState attached to @blk if any, else null.
  */
 BlockDriverState *blk_bs(BlockBackend *blk)
diff --git a/include/sysemu/block-backend.h b/include/sysemu/block-backend.h
index f1da495..7322db6 100644
--- a/include/sysemu/block-backend.h
+++ b/include/sysemu/block-backend.h
@@ -72,6 +72,7 @@  void blk_ref(BlockBackend *blk, Notifier *close_all_notifier);
 void blk_unref(BlockBackend *blk, Notifier *close_all_notifier);
 const char *blk_name(BlockBackend *blk);
 BlockBackend *blk_by_name(const char *name);
+bool blk_name_taken(const char *name);
 BlockBackend *blk_next(BlockBackend *blk);
 
 BlockDriverState *blk_bs(BlockBackend *blk);