Block patches

index e20f2e7..9e1bdd5 100644
@@ -1643,6 +1643,21 @@ static void ide_atapi_cmd(IDEState *s)
             ide_atapi_cmd_reply(s, len, max_len);
             break;
         }
+    case GPCMD_GET_EVENT_STATUS_NOTIFICATION:
+        max_len = ube16_to_cpu(packet + 7);
+
+        if (packet[1] & 0x01) { /* polling */
+            /* We don't support any event class (yet). */
+            cpu_to_ube16(buf, 0x00); /* No event descriptor returned */
+            buf[2] = 0x80;           /* No Event Available (NEA) */
+            buf[3] = 0x00;           /* Empty supported event classes */
+            ide_atapi_cmd_reply(s, 4, max_len);
+        } else { /* asynchronous mode */
+            /* Only polling is supported, asynchronous mode is not. */
+            ide_atapi_cmd_error(s, SENSE_ILLEGAL_REQUEST,
+                                ASC_INV_FIELD_IN_CMD_PACKET);
+        }
+        break;
     default:
         ide_atapi_cmd_error(s, SENSE_ILLEGAL_REQUEST,
                             ASC_ILLEGAL_OPCODE);

index a77106e..8eda307 100644
@@ -586,6 +586,7 @@ static int block_load(QEMUFile *f, void *opaque, int version_id)
         addr >>= BDRV_SECTOR_BITS;
 
         if (flags & BLK_MIG_FLAG_DEVICE_BLOCK) {
+            int ret;
             /* get device name */
             len = qemu_get_byte(f);
             qemu_get_buffer(f, (uint8_t *)device_name, len);

@@ -601,9 +602,12 @@ static int block_load(QEMUFile *f, void *opaque, int version_id)
             buf = qemu_malloc(BLOCK_SIZE);
 
             qemu_get_buffer(f, buf, BLOCK_SIZE);
-            bdrv_write(bs, addr, buf, BDRV_SECTORS_PER_DIRTY_CHUNK);
+            ret = bdrv_write(bs, addr, buf, BDRV_SECTORS_PER_DIRTY_CHUNK);
 
             qemu_free(buf);
+            if (ret < 0) {
+                return ret;
+            }
         } else if (flags & BLK_MIG_FLAG_PROGRESS) {
             if (!banner_printed) {
                 printf("Receiving block device images\n");

index f50069d..490cd41 100644
@@ -28,6 +28,7 @@ typedef struct VirtIOBlock
     BlockConf *conf;
     unsigned short sector_mask;
     char sn[BLOCK_SERIAL_STRLEN];
+    DeviceState *qdev;
 } VirtIOBlock;
 
 static VirtIOBlock *to_virtio_blk(VirtIODevice *vdev)

@@ -522,9 +523,16 @@ VirtIODevice *virtio_blk_init(DeviceState *dev, BlockConf *conf)
     s->vq = virtio_add_queue(&s->vdev, 128, virtio_blk_handle_output);
 
     qemu_add_vm_change_state_handler(virtio_blk_dma_restart_cb, s);
+    s->qdev = dev;
     register_savevm(dev, "virtio-blk", virtio_blk_id++, 2,
                     virtio_blk_save, virtio_blk_load, s);
     bdrv_set_removable(s->bs, 0);
 
     return &s->vdev;
 }
+
+void virtio_blk_exit(VirtIODevice *vdev)
+{
+    VirtIOBlock *s = to_virtio_blk(vdev);
+    unregister_savevm(s->qdev, "virtio-blk", s);
+}

index 31a711e..17c3d15 100644
@@ -569,6 +569,7 @@ static int virtio_blk_exit_pci(PCIDevice *pci_dev)
 {
     VirtIOPCIProxy *proxy = DO_UPCAST(VirtIOPCIProxy, pci_dev, pci_dev);
 
+    virtio_blk_exit(proxy->vdev);
     blockdev_mark_auto_del(proxy->block.bs);
     return virtio_exit_pci(pci_dev);
 }

index e4306cd..30e472a 100644
@@ -194,6 +194,7 @@ VirtIODevice *virtio_9p_init(DeviceState *dev, V9fsConf *conf);
 
 
 void virtio_net_exit(VirtIODevice *vdev);
+void virtio_blk_exit(VirtIODevice *vdev);
 
 #define DEFINE_VIRTIO_COMMON_FEATURES(_state, _field) \
 	DEFINE_PROP_BIT("indirect_desc", _state, _field, \

index 96ff4cf..f075a8c 100644
@@ -243,7 +243,7 @@ static inline unsigned int get_physical_block_exp(BlockConf *conf)
                        _conf.logical_block_size, 512),                  \
     DEFINE_PROP_UINT16("physical_block_size", _state,                   \
                        _conf.physical_block_size, 512),                 \
-    DEFINE_PROP_UINT16("min_io_size", _state, _conf.min_io_size, 512),  \
-    DEFINE_PROP_UINT32("opt_io_size", _state, _conf.opt_io_size, 512)
+    DEFINE_PROP_UINT16("min_io_size", _state, _conf.min_io_size, 0),  \
+    DEFINE_PROP_UINT32("opt_io_size", _state, _conf.opt_io_size, 0)
 
 #endif /* BLOCK_INT_H */

index f837876..49e6cbc 100644
@@ -330,7 +330,7 @@ BlockDriver *bdrv_find_protocol(const char *filename)
     return NULL;
 }
 
-static BlockDriver *find_image_format(const char *filename)
+static int find_image_format(const char *filename, BlockDriver **pdrv)
 {
     int ret, score, score_max;
     BlockDriver *drv1, *drv;

@@ -338,19 +338,27 @@ static BlockDriver *find_image_format(const char *filename)
     BlockDriverState *bs;
 
     ret = bdrv_file_open(&bs, filename, 0);
-    if (ret < 0)
-        return NULL;
+    if (ret < 0) {
+        *pdrv = NULL;
+        return ret;
+    }
 
     /* Return the raw BlockDriver * to scsi-generic devices or empty drives */
     if (bs->sg || !bdrv_is_inserted(bs)) {
         bdrv_delete(bs);
-        return bdrv_find_format("raw");
+        drv = bdrv_find_format("raw");
+        if (!drv) {
+            ret = -ENOENT;
+        }
+        *pdrv = drv;
+        return ret;
     }
 
     ret = bdrv_pread(bs, 0, buf, sizeof(buf));
     bdrv_delete(bs);
     if (ret < 0) {
-        return NULL;
+        *pdrv = NULL;
+        return ret;
     }
 
     score_max = 0;

@@ -364,7 +372,11 @@ static BlockDriver *find_image_format(const char *filename)
             }
         }
     }
-    return drv;
+    if (!drv) {
+        ret = -ENOENT;
+    }
+    *pdrv = drv;
+    return ret;
 }
 
 /**

@@ -571,12 +583,11 @@ int bdrv_open(BlockDriverState *bs, const char *filename, int flags,
 
     /* Find the right image format driver */
     if (!drv) {
-        drv = find_image_format(filename);
+        ret = find_image_format(filename, &drv);
         probed = 1;
     }
 
     if (!drv) {
-        ret = -ENOENT;
         goto unlink_and_fail;
     }
 

index 49e6cbc..452ae94 100644
@@ -1811,6 +1811,11 @@ int bdrv_can_snapshot(BlockDriverState *bs)
     return 1;
 }
 
+int bdrv_is_snapshot(BlockDriverState *bs)
+{
+    return !!(bs->open_flags & BDRV_O_SNAPSHOT);
+}
+
 BlockDriverState *bdrv_snapshots(void)
 {
     BlockDriverState *bs;

index c2a7e4c..db131a3 100644
@@ -202,6 +202,7 @@ const char *bdrv_get_encrypted_filename(BlockDriverState *bs);
 void bdrv_get_backing_filename(BlockDriverState *bs,
                                char *filename, int filename_size);
 int bdrv_can_snapshot(BlockDriverState *bs);
+int bdrv_is_snapshot(BlockDriverState *bs);
 BlockDriverState *bdrv_snapshots(void);
 int bdrv_snapshot_create(BlockDriverState *bs,
                          QEMUSnapshotInfo *sn_info);

index 0a9dec3..01e402b 100644
@@ -590,6 +590,7 @@ int do_change_block(Monitor *mon, const char *device,
         return -1;
     }
     bdrv_flags = bdrv_is_read_only(bs) ? 0 : BDRV_O_RDWR;
+    bdrv_flags |= bdrv_is_snapshot(bs) ? BDRV_O_SNAPSHOT : 0;
     if (bdrv_open(bs, filename, bdrv_flags, drv) < 0) {
         qerror_report(QERR_OPEN_FILE_FAILED, filename);
         return -1;