block: BLOCK_IO_ERROR QMP event

This commit introduces the bdrv_mon_event() function, which
should be called by block subsystems (eg. IDE) when a I/O
error occurs, so that an QMP event is emitted.

The following information is currently provided in the event:

- device name
- operation (ie. "read" or "write")
- action taken (eg. "stop")

Event example:

{ "event": "BLOCK_IO_ERROR",
    "data": { "device": "ide0-hd1",
              "operation": "write",
              "action": "stop" },
    "timestamp": { "seconds": 1265044230, "microseconds": 450486 } }

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/block.h b/block.h
index 536265e..edf5704 100644
--- a/block.h
+++ b/block.h
@@ -44,6 +44,12 @@ typedef struct QEMUSnapshotInfo {
 #define BDRV_SECTOR_SIZE   (1 << BDRV_SECTOR_BITS)
 #define BDRV_SECTOR_MASK   ~(BDRV_SECTOR_SIZE - 1);
 
+typedef enum {
+    BDRV_ACTION_REPORT, BDRV_ACTION_IGNORE, BDRV_ACTION_STOP
+} BlockMonEventAction;
+
+void bdrv_mon_event(const BlockDriverState *bdrv,
+                    BlockMonEventAction action, int is_read);
 void bdrv_info_print(Monitor *mon, const QObject *data);
 void bdrv_info(Monitor *mon, QObject **ret_data);
 void bdrv_stats_print(Monitor *mon, const QObject *data);