block: Use error code EMEDIUMTYPE for wrong format in some block drivers

This improves error reports for bochs, cow, qcow, qcow2, qed and vmdk
when a file with the wrong format is selected.
Signed-off-by: NStefan Weil <sw@weilnetz.de>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

block/bochs.c

@@ -126,7 +126,7 @@ static int bochs_open(BlockDriverState *bs, int flags)
         strcmp(bochs.subtype, GROWING_TYPE) ||
 	((le32_to_cpu(bochs.version) != HEADER_VERSION) &&
 	(le32_to_cpu(bochs.version) != HEADER_V1))) {
-        goto fail;
+        return -EMEDIUMTYPE;
     }
 
     if (le32_to_cpu(bochs.version) == HEADER_V1) {

block/cow.c

@@ -73,7 +73,7 @@ static int cow_open(BlockDriverState *bs, int flags)
     }
 
     if (be32_to_cpu(cow_header.magic) != COW_MAGIC) {
-        ret = -EINVAL;
+        ret = -EMEDIUMTYPE;
         goto fail;
     }
 

block/qcow.c

@@ -112,7 +112,7 @@ static int qcow_open(BlockDriverState *bs, int flags)
     be64_to_cpus(&header.l1_table_offset);
 
     if (header.magic != QCOW_MAGIC) {
-        ret = -EINVAL;
+        ret = -EMEDIUMTYPE;
         goto fail;
     }
     if (header.version != QCOW_VERSION) {

block/qcow2.c

@@ -311,7 +311,7 @@ static int qcow2_open(BlockDriverState *bs, int flags)
     be32_to_cpus(&header.nb_snapshots);
 
     if (header.magic != QCOW_MAGIC) {
-        ret = -EINVAL;
+        ret = -EMEDIUMTYPE;
         goto fail;
     }
     if (header.version < 2 || header.version > 3) {

block/qed.c

@@ -390,7 +390,7 @@ static int bdrv_qed_open(BlockDriverState *bs, int flags)
     qed_header_le_to_cpu(&le_header, &s->header);
 
     if (s->header.magic != QED_MAGIC) {
-        return -EINVAL;
+        return -EMEDIUMTYPE;
     }
     if (s->header.features & ~QED_FEATURE_MASK) {
         /* image uses unsupported feature bits */

block/vmdk.c

@@ -616,7 +616,7 @@ static int vmdk_open_sparse(BlockDriverState *bs,
             return vmdk_open_vmdk4(bs, file, flags);
             break;
         default:
-            return -EINVAL;
+            return -EMEDIUMTYPE;
             break;
     }
 }
@@ -718,7 +718,7 @@ static int vmdk_open_desc_file(BlockDriverState *bs, int flags,
     }
     buf[2047] = '\0';
     if (vmdk_parse_description(buf, "createType", ct, sizeof(ct))) {
-        return -EINVAL;
+        return -EMEDIUMTYPE;
     }
     if (strcmp(ct, "monolithicFlat") &&
         strcmp(ct, "twoGbMaxExtentSparse") &&