block: Add Error parameter to bdrv_amend_options

Looking at the qcow2 code that is riddled with error_report() calls,
this is really how it should have been from the start.

Along the way, turn the target_version/current_version comparisons at
the beginning of qcow2_downgrade() into assertions (the caller has to
make sure these conditions are met), and rephrase the error message on
using compat=1.1 to get refcount widths other than 16 bits.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20180509210023.20283-3-mreitz@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>

4 files changed, 5 insertions, 15 deletions

diff --git a/tests/qemu-iotests/060.out b/tests/qemu-iotests/060.out
index 25d5c3938b..5f4264cff6 100644
--- a/tests/qemu-iotests/060.out
+++ b/tests/qemu-iotests/060.out
@@ -129,7 +129,7 @@ Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864
 wrote 65536/65536 bytes at offset 0
 64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 qcow2: Marking image as corrupt: L2 table offset 0x42a00 unaligned (L1 index: 0); further corruption events will be suppressed
-qemu-img: Error while amending options: Input/output error
+qemu-img: Failed to turn zero into data clusters: Input/output error
 
 === Testing unaligned L2 entry ===
 
@@ -145,7 +145,7 @@ Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864
 wrote 65536/65536 bytes at offset 0
 64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 qcow2: Marking image as corrupt: Cluster allocation offset 0x52a00 unaligned (L2 offset: 0x40000, L2 index: 0); further corruption events will be suppressed
-qemu-img: Error while amending options: Input/output error
+qemu-img: Failed to turn zero into data clusters: Input/output error
 
 === Testing unaligned reftable entry ===
 
diff --git a/tests/qemu-iotests/061.out b/tests/qemu-iotests/061.out
index e857ef9a7d..183f7dd690 100644
--- a/tests/qemu-iotests/061.out
+++ b/tests/qemu-iotests/061.out
@@ -358,18 +358,12 @@ No errors were found on the image.
 
 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864
 qemu-img: Lazy refcounts only supported with compatibility level 1.1 and above (use compat=1.1 or greater)
-qemu-img: Error while amending options: Invalid argument
 qemu-img: Lazy refcounts only supported with compatibility level 1.1 and above (use compat=1.1 or greater)
-qemu-img: Error while amending options: Invalid argument
 qemu-img: Unknown compatibility level 0.42
-qemu-img: Error while amending options: Invalid argument
 qemu-img: Invalid parameter 'foo'
 qemu-img: Changing the cluster size is not supported
-qemu-img: Error while amending options: Operation not supported
 qemu-img: Changing the encryption flag is not supported
-qemu-img: Error while amending options: Operation not supported
 qemu-img: Cannot change preallocation mode
-qemu-img: Error while amending options: Operation not supported
 
 === Testing correct handling of unset value ===
 
@@ -377,7 +371,6 @@ Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864
 Should work:
 Should not work:
 qemu-img: Changing the cluster size is not supported
-qemu-img: Error while amending options: Operation not supported
 
 === Testing zero expansion on inactive clusters ===
 
diff --git a/tests/qemu-iotests/080.out b/tests/qemu-iotests/080.out
index 4e0f7f7b92..281c7e0d1d 100644
--- a/tests/qemu-iotests/080.out
+++ b/tests/qemu-iotests/080.out
@@ -65,7 +65,7 @@ wrote 512/512 bytes at offset 0
 512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 qemu-img: Failed to load snapshot: Snapshot L1 table offset invalid
 qemu-img: Snapshot L1 table offset invalid
-qemu-img: Error while amending options: Invalid argument
+qemu-img: Failed to turn zero into data clusters: Invalid argument
 Failed to flush the refcount block cache: Invalid argument
 write failed: Invalid argument
 qemu-img: Snapshot L1 table offset invalid
@@ -88,7 +88,7 @@ wrote 512/512 bytes at offset 0
 512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 qemu-img: Failed to load snapshot: Snapshot L1 table too large
 qemu-img: Snapshot L1 table too large
-qemu-img: Error while amending options: File too large
+qemu-img: Failed to turn zero into data clusters: File too large
 Failed to flush the refcount block cache: File too large
 write failed: File too large
 qemu-img: Snapshot L1 table too large
diff --git a/tests/qemu-iotests/112.out b/tests/qemu-iotests/112.out
index 86f041075d..ae0318cabe 100644
--- a/tests/qemu-iotests/112.out
+++ b/tests/qemu-iotests/112.out
@@ -99,13 +99,11 @@ refcount bits: 64
 === Amend to compat=0.10 ===
 
 qemu-img: compat=0.10 requires refcount_bits=16
-qemu-img: Error while amending options: Operation not supported
 refcount bits: 64
 No errors were found on the image.
 refcount bits: 16
 refcount bits: 16
-qemu-img: Different refcount widths than 16 bits require compatibility level 1.1 or above (use compat=1.1 or greater)
-qemu-img: Error while amending options: Invalid argument
+qemu-img: Refcount widths other than 16 bits require compatibility level 1.1 or above (use compat=1.1 or greater)
 refcount bits: 16
 
 === Amend with snapshot ===
@@ -113,7 +111,6 @@ refcount bits: 16
 wrote 16777216/16777216 bytes at offset 0
 16 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 qemu-img: Cannot decrease refcount entry width to 1 bits: Cluster at offset 0x50000 has a refcount of 2
-qemu-img: Error while amending options: Invalid argument
 No errors were found on the image.
 refcount bits: 16
 No errors were found on the image.