* [PULL 1/2] qcow2: Release read-only bitmaps when inactivated
2020-08-03 14:11 [PULL 0/2] bitmaps patches for -rc3, 2020-08-03 Eric Blake
@ 2020-08-03 14:11 ` Eric Blake
2020-08-03 14:11 ` [PULL 2/2] iotests/169: Test source cont with backing bmap Eric Blake
2020-08-03 16:02 ` [PULL 0/2] bitmaps patches for -rc3, 2020-08-03 Peter Maydell
2 siblings, 0 replies; 4+ messages in thread
From: Eric Blake @ 2020-08-03 14:11 UTC (permalink / raw)
To: qemu-devel
Cc: Kevin Wolf, Peter Krempa, open list:qcow2, Max Reitz,
Vladimir Sementsov-Ogievskiy, John Snow
From: Max Reitz <mreitz@redhat.com>
During migration, we release all bitmaps after storing them on disk, as
long as they are (1) stored on disk, (2) not read-only, and (3)
consistent.
(2) seems arbitrary, though. The reason we do not release them is
because we do not write them, as there is no need to; and then we just
forget about all bitmaps that we have not written to the file. However,
read-only persistent bitmaps are still in the file and in sync with
their in-memory representation, so we may as well release them just like
any R/W bitmap that we have updated.
It leads to actual problems, too: After migration, letting the source
continue may result in an error if there were any bitmaps on read-only
nodes (such as backing images), because those have not been released by
bdrv_inactive_all(), but bdrv_invalidate_cache_all() attempts to reload
them (which fails, because they are still present in memory).
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200730120234.49288-2-mreitz@redhat.com>
Tested-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
---
block/qcow2-bitmap.c | 23 +++++++++++++++++++----
1 file changed, 19 insertions(+), 4 deletions(-)
diff --git a/block/qcow2-bitmap.c b/block/qcow2-bitmap.c
index 1f38806ca6ea..8c34b2aef7cd 100644
--- a/block/qcow2-bitmap.c
+++ b/block/qcow2-bitmap.c
@@ -1562,11 +1562,22 @@ void qcow2_store_persistent_dirty_bitmaps(BlockDriverState *bs,
Qcow2Bitmap *bm;
if (!bdrv_dirty_bitmap_get_persistence(bitmap) ||
- bdrv_dirty_bitmap_readonly(bitmap) ||
bdrv_dirty_bitmap_inconsistent(bitmap)) {
continue;
}
+ if (bdrv_dirty_bitmap_readonly(bitmap)) {
+ /*
+ * Store the bitmap in the associated Qcow2Bitmap so it
+ * can be released later
+ */
+ bm = find_bitmap_by_name(bm_list, name);
+ if (bm) {
+ bm->dirty_bitmap = bitmap;
+ }
+ continue;
+ }
+
need_write = true;
if (check_constraints_on_bitmap(bs, name, granularity, errp) < 0) {
@@ -1618,7 +1629,9 @@ void qcow2_store_persistent_dirty_bitmaps(BlockDriverState *bs,
/* allocate clusters and store bitmaps */
QSIMPLEQ_FOREACH(bm, bm_list, entry) {
- if (bm->dirty_bitmap == NULL) {
+ BdrvDirtyBitmap *bitmap = bm->dirty_bitmap;
+
+ if (bitmap == NULL || bdrv_dirty_bitmap_readonly(bitmap)) {
continue;
}
@@ -1641,6 +1654,7 @@ void qcow2_store_persistent_dirty_bitmaps(BlockDriverState *bs,
g_free(tb);
}
+success:
if (release_stored) {
QSIMPLEQ_FOREACH(bm, bm_list, entry) {
if (bm->dirty_bitmap == NULL) {
@@ -1651,13 +1665,14 @@ void qcow2_store_persistent_dirty_bitmaps(BlockDriverState *bs,
}
}
-success:
bitmap_list_free(bm_list);
return;
fail:
QSIMPLEQ_FOREACH(bm, bm_list, entry) {
- if (bm->dirty_bitmap == NULL || bm->table.offset == 0) {
+ if (bm->dirty_bitmap == NULL || bm->table.offset == 0 ||
+ bdrv_dirty_bitmap_readonly(bm->dirty_bitmap))
+ {
continue;
}
--
2.28.0
^ permalink raw reply related [flat|nested] 4+ messages in thread* [PULL 2/2] iotests/169: Test source cont with backing bmap
2020-08-03 14:11 [PULL 0/2] bitmaps patches for -rc3, 2020-08-03 Eric Blake
2020-08-03 14:11 ` [PULL 1/2] qcow2: Release read-only bitmaps when inactivated Eric Blake
@ 2020-08-03 14:11 ` Eric Blake
2020-08-03 16:02 ` [PULL 0/2] bitmaps patches for -rc3, 2020-08-03 Peter Maydell
2 siblings, 0 replies; 4+ messages in thread
From: Eric Blake @ 2020-08-03 14:11 UTC (permalink / raw)
To: qemu-devel; +Cc: Kevin Wolf, open list:Block layer core, Max Reitz
From: Max Reitz <mreitz@redhat.com>
Test migrating from a VM with a persistent bitmap in the backing chain,
and then continuing that VM after the migration
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200730120234.49288-3-mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
---
tests/qemu-iotests/169 | 64 +++++++++++++++++++++++++++++++++++++-
tests/qemu-iotests/169.out | 4 +--
2 files changed, 65 insertions(+), 3 deletions(-)
diff --git a/tests/qemu-iotests/169 b/tests/qemu-iotests/169
index 2c5a132aa315..40afb1529986 100755
--- a/tests/qemu-iotests/169
+++ b/tests/qemu-iotests/169
@@ -24,11 +24,12 @@ import time
import itertools
import operator
import re
-from iotests import qemu_img
+from iotests import qemu_img, qemu_img_create, Timeout
disk_a = os.path.join(iotests.test_dir, 'disk_a')
disk_b = os.path.join(iotests.test_dir, 'disk_b')
+base_a = os.path.join(iotests.test_dir, 'base_a')
size = '1M'
mig_file = os.path.join(iotests.test_dir, 'mig_file')
mig_cmd = 'exec: cat > ' + mig_file
@@ -234,6 +235,67 @@ for cmb in list(itertools.product((True, False), repeat=2)):
inject_test_case(TestDirtyBitmapMigration, name,
'do_test_migration_resume_source', *list(cmb))
+
+class TestDirtyBitmapBackingMigration(iotests.QMPTestCase):
+ def setUp(self):
+ qemu_img_create('-f', iotests.imgfmt, base_a, size)
+ qemu_img_create('-f', iotests.imgfmt, '-F', iotests.imgfmt,
+ '-b', base_a, disk_a, size)
+
+ for f in (disk_a, base_a):
+ qemu_img('bitmap', '--add', f, 'bmap0')
+
+ blockdev = {
+ 'node-name': 'node0',
+ 'driver': iotests.imgfmt,
+ 'file': {
+ 'driver': 'file',
+ 'filename': disk_a
+ },
+ 'backing': {
+ 'node-name': 'node0-base',
+ 'driver': iotests.imgfmt,
+ 'file': {
+ 'driver': 'file',
+ 'filename': base_a
+ }
+ }
+ }
+
+ self.vm = iotests.VM()
+ self.vm.launch()
+
+ result = self.vm.qmp('blockdev-add', **blockdev)
+ self.assert_qmp(result, 'return', {})
+
+ # Check that the bitmaps are there
+ for node in self.vm.qmp('query-named-block-nodes', flat=True)['return']:
+ if 'node0' in node['node-name']:
+ self.assert_qmp(node, 'dirty-bitmaps[0]/name', 'bmap0')
+
+ caps = [{'capability': 'events', 'state': True}]
+ result = self.vm.qmp('migrate-set-capabilities', capabilities=caps)
+ self.assert_qmp(result, 'return', {})
+
+ def tearDown(self):
+ self.vm.shutdown()
+ for f in (disk_a, base_a):
+ os.remove(f)
+
+ def test_cont_on_source(self):
+ """
+ Continue the source after migration.
+ """
+ result = self.vm.qmp('migrate', uri=f'exec: cat > /dev/null')
+ self.assert_qmp(result, 'return', {})
+
+ with Timeout(10, 'Migration timeout'):
+ self.vm.wait_migration('postmigrate')
+
+ result = self.vm.qmp('cont')
+ self.assert_qmp(result, 'return', {})
+
+
if __name__ == '__main__':
iotests.main(supported_fmts=['qcow2'],
supported_protocols=['file'])
diff --git a/tests/qemu-iotests/169.out b/tests/qemu-iotests/169.out
index 5c26d15c0d06..cafb8161f7b1 100644
--- a/tests/qemu-iotests/169.out
+++ b/tests/qemu-iotests/169.out
@@ -1,5 +1,5 @@
-....................................
+.....................................
----------------------------------------------------------------------
-Ran 36 tests
+Ran 37 tests
OK
--
2.28.0
^ permalink raw reply related [flat|nested] 4+ messages in thread