diff mbox series

[v8,1/7] block: teach bdrv_debug_breakpoint skip filters with backing

Message ID 20190529154654.95870-2-vsementsov@virtuozzo.com
State New
Headers show
Series backup-top filter driver for backup | expand

Commit Message

Vladimir Sementsov-Ogievskiy May 29, 2019, 3:46 p.m. UTC 
Teach bdrv_debug_breakpoint and bdrv_debug_remove_breakpoint skip
filters with backing. This is needed to implement and use in backup job
it's own backup_top filter driver (like mirror already has one), and
without this improvement, breakpoint removal will fail at least in 55
iotest.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 block.c | 34 ++++++++++++++++++++++++++--------
 1 file changed, 26 insertions(+), 8 deletions(-)

Comments

Max Reitz June 13, 2019, 1:43 p.m. UTC | #1 
On 29.05.19 17:46, Vladimir Sementsov-Ogievskiy wrote:
> Teach bdrv_debug_breakpoint and bdrv_debug_remove_breakpoint skip
> filters with backing. This is needed to implement and use in backup job
> it's own backup_top filter driver (like mirror already has one), and
> without this improvement, breakpoint removal will fail at least in 55
> iotest.
> 
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> ---
>  block.c | 34 ++++++++++++++++++++++++++--------
>  1 file changed, 26 insertions(+), 8 deletions(-)

Well, it would work in the meantime, but the real fix of course is to
use bdrv_primary_bs().

Max
diff mbox series

Patch

diff --git a/block.c b/block.c
index 1a73e310c1..e6e9770704 100644
--- a/block.c
+++ b/block.c
@@ -4982,14 +4982,35 @@  void bdrv_debug_event(BlockDriverState *bs, BlkdebugEvent event)
     bs->drv->bdrv_debug_event(bs, event);
 }
 
-int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event,
-                          const char *tag)
+static BlockDriverState *bdrv_find_debug_node(BlockDriverState *bs)
 {
     while (bs && bs->drv && !bs->drv->bdrv_debug_breakpoint) {
-        bs = bs->file ? bs->file->bs : NULL;
+        if (bs->file) {
+            bs = bs->file->bs;
+            continue;
+        }
+
+        if (bs->drv->is_filter && bs->backing) {
+            bs = bs->backing->bs;
+            continue;
+        }
+
+        break;
     }
 
     if (bs && bs->drv && bs->drv->bdrv_debug_breakpoint) {
+        assert(bs->drv->bdrv_debug_remove_breakpoint);
+        return bs;
+    }
+
+    return NULL;
+}
+
+int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event,
+                          const char *tag)
+{
+    bs = bdrv_find_debug_node(bs);
+    if (bs) {
         return bs->drv->bdrv_debug_breakpoint(bs, event, tag);
     }
 
@@ -4998,11 +5019,8 @@  int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event,
 
 int bdrv_debug_remove_breakpoint(BlockDriverState *bs, const char *tag)
 {
-    while (bs && bs->drv && !bs->drv->bdrv_debug_remove_breakpoint) {
-        bs = bs->file ? bs->file->bs : NULL;
-    }
-
-    if (bs && bs->drv && bs->drv->bdrv_debug_remove_breakpoint) {
+    bs = bdrv_find_debug_node(bs);
+    if (bs) {
         return bs->drv->bdrv_debug_remove_breakpoint(bs, tag);
     }