[PATCH v2 2/4] qcow2: List autoclear bit names in header

Eric Blake posted 4 patches 8 weeks ago
Maintainers: Max Reitz <mreitz@redhat.com>, Kevin Wolf <kwolf@redhat.com>, Liu Yuan <namei.unix@gmail.com>

[PATCH v2 2/4] qcow2: List autoclear bit names in header

Posted by Eric Blake 8 weeks ago
The feature table is supposed to advertise the name of all feature
bits that we support; however, we forgot to update the table for
autoclear bits.  While at it, move the table to read-only memory in
code, and tweak the qcow2 spec to name the second autoclear bit.
Update iotests that are affected by the longer header length.

Fixes: 88ddffae
Fixes: 93c24936
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>

---
[v2] tweak name of "bitmaps" autoclear bit [Vladimir]
---
 docs/interop/qcow2.txt     |  3 ++-
 block/qcow2.c              | 12 +++++++++++-
 tests/qemu-iotests/031.out |  8 ++++----
 tests/qemu-iotests/036.out |  4 ++--
 tests/qemu-iotests/061.out | 14 +++++++-------
 5 files changed, 26 insertions(+), 15 deletions(-)

diff --git a/docs/interop/qcow2.txt b/docs/interop/qcow2.txt
index 5597e244746e..640e0eca4000 100644
--- a/docs/interop/qcow2.txt
+++ b/docs/interop/qcow2.txt
@@ -143,7 +143,8 @@ the next fields through header_length.
                                 bit is unset, the bitmaps extension data must be
                                 considered inconsistent.

-                    Bit 1:      If this bit is set, the external data file can
+                    Bit 1:      Raw external data bit
+                                If this bit is set, the external data file can
                                 be read as a consistent standalone raw image
                                 without looking at the qcow2 metadata.

diff --git a/block/qcow2.c b/block/qcow2.c
index 5a7f30e692a2..67b0c214fba4 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -2825,7 +2825,7 @@ int qcow2_update_header(BlockDriverState *bs)

     /* Feature table */
     if (s->qcow_version >= 3) {
-        Qcow2Feature features[] = {
+        static const Qcow2Feature features[] = {
             {
                 .type = QCOW2_FEAT_TYPE_INCOMPATIBLE,
                 .bit  = QCOW2_INCOMPAT_DIRTY_BITNR,
@@ -2846,6 +2846,16 @@ int qcow2_update_header(BlockDriverState *bs)
                 .bit  = QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR,
                 .name = "lazy refcounts",
             },
+            {
+                .type = QCOW2_FEAT_TYPE_AUTOCLEAR,
+                .bit  = QCOW2_AUTOCLEAR_BITMAPS_BITNR,
+                .name = "bitmaps",
+            },
+            {
+                .type = QCOW2_FEAT_TYPE_AUTOCLEAR,
+                .bit  = QCOW2_AUTOCLEAR_DATA_FILE_RAW_BITNR,
+                .name = "raw external data",
+            },
         };

         ret = header_ext_add(buf, QCOW2_EXT_MAGIC_FEATURE_TABLE,
diff --git a/tests/qemu-iotests/031.out b/tests/qemu-iotests/031.out
index d535e407bc30..46f97c5a4ea4 100644
--- a/tests/qemu-iotests/031.out
+++ b/tests/qemu-iotests/031.out
@@ -117,7 +117,7 @@ header_length             104

 Header extension:
 magic                     0x6803f857
-length                    192
+length                    288
 data                      <binary>

 Header extension:
@@ -150,7 +150,7 @@ header_length             104

 Header extension:
 magic                     0x6803f857
-length                    192
+length                    288
 data                      <binary>

 Header extension:
@@ -164,7 +164,7 @@ No errors were found on the image.

 magic                     0x514649fb
 version                   3
-backing_file_offset       0x178
+backing_file_offset       0x1d8
 backing_file_size         0x17
 cluster_bits              16
 size                      67108864
@@ -188,7 +188,7 @@ data                      'host_device'

 Header extension:
 magic                     0x6803f857
-length                    192
+length                    288
 data                      <binary>

 Header extension:
diff --git a/tests/qemu-iotests/036.out b/tests/qemu-iotests/036.out
index 0b52b934e115..23b699ce0622 100644
--- a/tests/qemu-iotests/036.out
+++ b/tests/qemu-iotests/036.out
@@ -26,7 +26,7 @@ compatible_features       []
 autoclear_features        [63]
 Header extension:
 magic                     0x6803f857
-length                    192
+length                    288
 data                      <binary>


@@ -38,7 +38,7 @@ compatible_features       []
 autoclear_features        []
 Header extension:
 magic                     0x6803f857
-length                    192
+length                    288
 data                      <binary>

 *** done
diff --git a/tests/qemu-iotests/061.out b/tests/qemu-iotests/061.out
index 8b3091a412bc..413cc4e0f4ab 100644
--- a/tests/qemu-iotests/061.out
+++ b/tests/qemu-iotests/061.out
@@ -26,7 +26,7 @@ header_length             104

 Header extension:
 magic                     0x6803f857
-length                    192
+length                    288
 data                      <binary>

 magic                     0x514649fb
@@ -84,7 +84,7 @@ header_length             104

 Header extension:
 magic                     0x6803f857
-length                    192
+length                    288
 data                      <binary>

 magic                     0x514649fb
@@ -140,7 +140,7 @@ header_length             104

 Header extension:
 magic                     0x6803f857
-length                    192
+length                    288
 data                      <binary>

 ERROR cluster 5 refcount=0 reference=1
@@ -195,7 +195,7 @@ header_length             104

 Header extension:
 magic                     0x6803f857
-length                    192
+length                    288
 data                      <binary>

 magic                     0x514649fb
@@ -264,7 +264,7 @@ header_length             104

 Header extension:
 magic                     0x6803f857
-length                    192
+length                    288
 data                      <binary>

 read 65536/65536 bytes at offset 44040192
@@ -298,7 +298,7 @@ header_length             104

 Header extension:
 magic                     0x6803f857
-length                    192
+length                    288
 data                      <binary>

 ERROR cluster 5 refcount=0 reference=1
@@ -327,7 +327,7 @@ header_length             104

 Header extension:
 magic                     0x6803f857
-length                    192
+length                    288
 data                      <binary>

 read 131072/131072 bytes at offset 0
-- 
2.26.0.rc2