block: Change BDS parameter of bdrv_open() to **

Make bdrv_open() take a pointer to a BDS pointer, similarly to
bdrv_file_open(). If a pointer to a NULL pointer is given, bdrv_open()
will create a new BDS with an empty name; if the BDS pointer is not
NULL, that existing BDS will be reused (in the same way as bdrv_open()
already did).

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

5 files changed, 16 insertions, 12 deletions

diff --git a/block/blkdebug.c b/block/blkdebug.c
index ee10013..46bd086 100644
--- a/block/blkdebug.c
+++ b/block/blkdebug.c
@@ -410,6 +410,7 @@ static int blkdebug_open(BlockDriverState *bs, QDict *options, int flags,
     s->state = 1;
 
     /* Open the backing file */
+    assert(bs->file == NULL);
     ret = bdrv_open_image(&bs->file, qemu_opt_get(opts, "x-image"), options, "image",
                           flags, true, false, &local_err);
     if (ret < 0) {
diff --git a/block/blkverify.c b/block/blkverify.c
index 1563c88..7d8a32e 100644
--- a/block/blkverify.c
+++ b/block/blkverify.c
@@ -135,6 +135,7 @@ static int blkverify_open(BlockDriverState *bs, QDict *options, int flags,
     }
 
     /* Open the raw file */
+    assert(bs->file == NULL);
     ret = bdrv_open_image(&bs->file, qemu_opt_get(opts, "x-raw"), options,
                           "raw", flags, true, false, &local_err);
     if (ret < 0) {
@@ -143,6 +144,7 @@ static int blkverify_open(BlockDriverState *bs, QDict *options, int flags,
     }
 
     /* Open the test file */
+    assert(s->test_file == NULL);
     ret = bdrv_open_image(&s->test_file, qemu_opt_get(opts, "x-image"), options,
                           "test", flags, false, false, &local_err);
     if (ret < 0) {
diff --git a/block/qcow2.c b/block/qcow2.c
index b1dbdb1..309ea12 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -1543,7 +1543,8 @@ static int qcow2_create2(const char *filename, int64_t total_size,
         goto out;
     }
 
-    bdrv_close(bs);
+    bdrv_unref(bs);
+    bs = NULL;
 
     /*
      * And now open the image and make it consistent first (i.e. increase the
@@ -1552,7 +1553,7 @@ static int qcow2_create2(const char *filename, int64_t total_size,
      */
     BlockDriver* drv = bdrv_find_format("qcow2");
     assert(drv != NULL);
-    ret = bdrv_open(bs, filename, NULL,
+    ret = bdrv_open(&bs, filename, NULL,
         BDRV_O_RDWR | BDRV_O_CACHE_WB | BDRV_O_NO_FLUSH, drv, &local_err);
     if (ret < 0) {
         error_propagate(errp, local_err);
@@ -1599,10 +1600,11 @@ static int qcow2_create2(const char *filename, int64_t total_size,
         }
     }
 
-    bdrv_close(bs);
+    bdrv_unref(bs);
+    bs = NULL;
 
     /* Reopen the image without BDRV_O_NO_FLUSH to flush it before returning */
-    ret = bdrv_open(bs, filename, NULL,
+    ret = bdrv_open(&bs, filename, NULL,
                     BDRV_O_RDWR | BDRV_O_CACHE_WB | BDRV_O_NO_BACKING,
                     drv, &local_err);
     if (local_err) {
@@ -1612,7 +1614,9 @@ static int qcow2_create2(const char *filename, int64_t total_size,
 
     ret = 0;
 out:
-    bdrv_unref(bs);
+    if (bs) {
+        bdrv_unref(bs);
+    }
     return ret;
 }
 
diff --git a/block/vmdk.c b/block/vmdk.c
index ff6f5ee..0622db5 100644
--- a/block/vmdk.c
+++ b/block/vmdk.c
@@ -1755,10 +1755,9 @@ static int vmdk_create(const char *filename, QEMUOptionParameter *options,
         goto exit;
     }
     if (backing_file) {
-        BlockDriverState *bs = bdrv_new("");
-        ret = bdrv_open(bs, backing_file, NULL, BDRV_O_NO_BACKING, NULL, errp);
+        BlockDriverState *bs = NULL;
+        ret = bdrv_open(&bs, backing_file, NULL, BDRV_O_NO_BACKING, NULL, errp);
         if (ret != 0) {
-            bdrv_unref(bs);
             goto exit;
         }
         if (strcmp(bs->drv->format_name, "vmdk")) {
diff --git a/block/vvfat.c b/block/vvfat.c
index a19e4ca..0a9f886 100644
--- a/block/vvfat.c
+++ b/block/vvfat.c
@@ -2936,15 +2936,13 @@ static int enable_write_target(BDRVVVFATState *s)
         goto err;
     }
 
-    s->qcow = bdrv_new("");
-
-    ret = bdrv_open(s->qcow, s->qcow_filename, NULL,
+    s->qcow = NULL;
+    ret = bdrv_open(&s->qcow, s->qcow_filename, NULL,
             BDRV_O_RDWR | BDRV_O_CACHE_WB | BDRV_O_NO_FLUSH, bdrv_qcow,
             &local_err);
     if (ret < 0) {
         qerror_report_err(local_err);
         error_free(local_err);
-        bdrv_unref(s->qcow);
         goto err;
     }