[Qemu-devel] [PATCH 2/2] ide: Handle flush failure

[Kevin Wolf <kwolf@redhat.com>]

Instead of always assuming success for bdrv_aio_flush, actually do something
with the error. This respects the werror option and accordingly ignores the
error, reports it to the guest or stops the VM and retries after cont.

Ignoring the error is trivial, obviously. For stopping the VM and retrying
later old code can be reused, but we need to introduce a new status for "retry
a flush". For reporting to the guest, fortunately the same action is required
as for a failed read/write (status = DRDY | ERR, error = ABRT), so this code
can be reused as well.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 hw/ide/core.c     |   10 +++++++++-
 hw/ide/internal.h |    3 ++-
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/hw/ide/core.c b/hw/ide/core.c
index 6d8606e..bc3e916 100644
--- a/hw/ide/core.c
+++ b/hw/ide/core.c
@@ -65,6 +65,7 @@ static void ide_dma_start(IDEState *s, BlockDriverCompletionFunc *dma_cb);
 static void ide_dma_restart(IDEState *s, int is_read);
 static void ide_atapi_cmd_read_dma_cb(void *opaque, int ret);
 static int ide_handle_rw_error(IDEState *s, int error, int op);
+static void ide_flush_cache(IDEState *s);
 
 static void padstr(char *str, const char *src, int len)
 {
@@ -688,6 +689,8 @@ static void ide_dma_restart_bh(void *opaque)
         } else {
             ide_sector_write(bmdma_active_if(bm));
         }
+    } else if (bm->status & BM_STATUS_RETRY_FLUSH) {
+        ide_flush_cache(bmdma_active_if(bm));
     }
 }
 
@@ -795,7 +798,12 @@ static void ide_flush_cb(void *opaque, int ret)
 {
     IDEState *s = opaque;
 
-    /* XXX: how do we signal I/O errors here? */
+    if (ret < 0) {
+        /* XXX: What sector number to set here? */
+        if (ide_handle_rw_error(s, -ret, BM_STATUS_RETRY_FLUSH)) {
+            return;
+        }
+    }
 
     s->status = READY_STAT | SEEK_STAT;
     ide_set_irq(s->bus);
diff --git a/hw/ide/internal.h b/hw/ide/internal.h
index 4165543..d652e06 100644
--- a/hw/ide/internal.h
+++ b/hw/ide/internal.h
@@ -472,7 +472,8 @@ struct IDEDeviceInfo {
 #define BM_STATUS_INT    0x04
 #define BM_STATUS_DMA_RETRY  0x08
 #define BM_STATUS_PIO_RETRY  0x10
-#define BM_STATUS_RETRY_READ 0x20
+#define BM_STATUS_RETRY_READ  0x20
+#define BM_STATUS_RETRY_FLUSH 0x40
 
 #define BM_CMD_START     0x01
 #define BM_CMD_READ      0x08
-- 
1.7.2.3