| Message ID | 5cc70489bfeb7d2f8f6c8a113dc530cab504db9e.1584468723.git.berto@igalia.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add subcluster allocation to qcow2 | expand |
On 17.03.20 19:16, Alberto Garcia wrote: > This function is only used by qcow2_expand_zero_clusters() to > downgrade a qcow2 image to a previous version. It is however not > possible to downgrade an image with extended L2 entries because older > versions of qcow2 do not have this feature. > > Signed-off-by: Alberto Garcia <berto@igalia.com> > --- > block/qcow2-cluster.c | 8 +++++++- > tests/qemu-iotests/061 | 6 ++++++ > tests/qemu-iotests/061.out | 5 +++++ > 3 files changed, 18 insertions(+), 1 deletion(-) [...] > diff --git a/tests/qemu-iotests/061 b/tests/qemu-iotests/061 > index 36b040491f..66bfd23179 100755 > --- a/tests/qemu-iotests/061 > +++ b/tests/qemu-iotests/061 > @@ -266,6 +266,12 @@ $QEMU_IMG amend -o "compat=0.10" "$TEST_IMG" > _img_info --format-specific > _check_test_img > > +echo > +echo "=== Testing version downgrade with extended L2 entries ===" > +echo > +_make_test_img -o "compat=1.1,extended_l2=on" 64M > +$QEMU_IMG amend -o "compat=0.10" "$TEST_IMG" > + > echo > echo "=== Try changing the external data file ===" > echo > diff --git a/tests/qemu-iotests/061.out b/tests/qemu-iotests/061.out > index 8b3091a412..5d009867a2 100644 > --- a/tests/qemu-iotests/061.out > +++ b/tests/qemu-iotests/061.out > @@ -498,6 +498,11 @@ Format specific information: > corrupt: false > No errors were found on the image. > > +=== Testing version downgrade with extended L2 entries === > + > +Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864 > +qemu-img: Cannot downgrade an image with incompatible features 0x10 set This test fails in this commit, because extended_l2 is only available after the next commit. The code changes and the test itself look good to me, though. Max
On Thu 09 Apr 2020 12:27:36 PM CEST, Max Reitz wrote: >> +=== Testing version downgrade with extended L2 entries === >> + >> +Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864 >> +qemu-img: Cannot downgrade an image with incompatible features 0x10 set > > This test fails in this commit, because extended_l2 is only available > after the next commit. The code changes and the test itself look good > to me, though. You're right, thanks! Since this one only adds an assertion I'll just swap both commits. Berto
diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index 1f471db98c..125d2852f6 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -2039,6 +2039,9 @@ static int expand_zero_clusters_in_l1(BlockDriverState *bs, uint64_t *l1_table, int ret; int i, j; + /* qcow2_downgrade() is not allowed in images with subclusters */ + assert(!has_subclusters(s)); + slice_size2 = s->l2_slice_size * l2_entry_size(s); n_slices = s->cluster_size / slice_size2; @@ -2107,7 +2110,8 @@ static int expand_zero_clusters_in_l1(BlockDriverState *bs, uint64_t *l1_table, if (cluster_type == QCOW2_CLUSTER_ZERO_PLAIN) { if (!bs->backing) { /* not backed; therefore we can simply deallocate the - * cluster */ + * cluster. No need to call set_l2_bitmap(), this + * function doesn't support images with subclusters. */ set_l2_entry(s, l2_slice, j, 0); l2_dirty = true; continue; @@ -2178,6 +2182,8 @@ static int expand_zero_clusters_in_l1(BlockDriverState *bs, uint64_t *l1_table, } else { set_l2_entry(s, l2_slice, j, offset); } + /* No need to call set_l2_bitmap() after set_l2_entry() because + * this function doesn't support images with subclusters. */ l2_dirty = true; } diff --git a/tests/qemu-iotests/061 b/tests/qemu-iotests/061 index 36b040491f..66bfd23179 100755 --- a/tests/qemu-iotests/061 +++ b/tests/qemu-iotests/061 @@ -266,6 +266,12 @@ $QEMU_IMG amend -o "compat=0.10" "$TEST_IMG" _img_info --format-specific _check_test_img +echo +echo "=== Testing version downgrade with extended L2 entries ===" +echo +_make_test_img -o "compat=1.1,extended_l2=on" 64M +$QEMU_IMG amend -o "compat=0.10" "$TEST_IMG" + echo echo "=== Try changing the external data file ===" echo diff --git a/tests/qemu-iotests/061.out b/tests/qemu-iotests/061.out index 8b3091a412..5d009867a2 100644 --- a/tests/qemu-iotests/061.out +++ b/tests/qemu-iotests/061.out @@ -498,6 +498,11 @@ Format specific information: corrupt: false No errors were found on the image. +=== Testing version downgrade with extended L2 entries === + +Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864 +qemu-img: Cannot downgrade an image with incompatible features 0x10 set + === Try changing the external data file === Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864
This function is only used by qcow2_expand_zero_clusters() to downgrade a qcow2 image to a previous version. It is however not possible to downgrade an image with extended L2 entries because older versions of qcow2 do not have this feature. Signed-off-by: Alberto Garcia <berto@igalia.com> --- block/qcow2-cluster.c | 8 +++++++- tests/qemu-iotests/061 | 6 ++++++ tests/qemu-iotests/061.out | 5 +++++ 3 files changed, 18 insertions(+), 1 deletion(-)