* [Qemu-devel] [PATCH v3 1/2] qemu-img: Add --backing-chain option to info command
2012-10-17 12:02 [Qemu-devel] [PATCH v3 0/2] qemu-img: Add --backing-chain option to info command Stefan Hajnoczi
@ 2012-10-17 12:02 ` Stefan Hajnoczi
2012-10-17 12:02 ` [Qemu-devel] [PATCH v3 2/2] qemu-iotests: Add 043 backing file chain infinite loop test Stefan Hajnoczi
2012-10-17 14:47 ` [Qemu-devel] [PATCH v3 0/2] qemu-img: Add --backing-chain option to info command Kevin Wolf
2 siblings, 0 replies; 5+ messages in thread
From: Stefan Hajnoczi @ 2012-10-17 12:02 UTC (permalink / raw)
To: qemu-devel; +Cc: Kevin Wolf, kashyap.cv, Benoît Canet, Stefan Hajnoczi
The qemu-img info --backing-chain option enumerates the backing file
chain. For example, for base.qcow2 <- snap1.qcow2 <- snap2.qcow2 the
output becomes:
$ qemu-img info --backing-chain snap2.qcow2
image: snap2.qcow2
file format: qcow2
virtual size: 100M (104857600 bytes)
disk size: 196K
cluster_size: 65536
backing file: snap1.qcow2
backing file format: qcow2
image: snap1.qcow2
file format: qcow2
virtual size: 100M (104857600 bytes)
disk size: 196K
cluster_size: 65536
backing file: base.qcow2
backing file format: qcow2
image: base.qcow2
file format: qcow2
virtual size: 100M (104857600 bytes)
disk size: 136K
cluster_size: 65536
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
qemu-img.c | 167 +++++++++++++++++++++++++++++++++++++++++++++++++++++++------
1 file changed, 153 insertions(+), 14 deletions(-)
diff --git a/qemu-img.c b/qemu-img.c
index f17f187..7261be9 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -1108,6 +1108,23 @@ static void dump_snapshots(BlockDriverState *bs)
g_free(sn_tab);
}
+static void dump_json_image_info_list(ImageInfoList *list)
+{
+ Error *errp = NULL;
+ QString *str;
+ QmpOutputVisitor *ov = qmp_output_visitor_new();
+ QObject *obj;
+ visit_type_ImageInfoList(qmp_output_get_visitor(ov),
+ &list, NULL, &errp);
+ obj = qmp_output_get_qobject(ov);
+ str = qobject_to_json_pretty(obj);
+ assert(str != NULL);
+ printf("%s\n", qstring_get_str(str));
+ qobject_decref(obj);
+ qmp_output_visitor_cleanup(ov);
+ QDECREF(str);
+}
+
static void collect_snapshots(BlockDriverState *bs , ImageInfo *info)
{
int i, sn_count;
@@ -1247,9 +1264,129 @@ static void dump_human_image_info(ImageInfo *info)
printf("backing file format: %s\n", info->backing_filename_format);
}
}
+
+ if (info->has_snapshots) {
+ SnapshotInfoList *elem;
+ char buf[256];
+
+ printf("Snapshot list:\n");
+ printf("%s\n", bdrv_snapshot_dump(buf, sizeof(buf), NULL));
+
+ /* Ideally bdrv_snapshot_dump() would operate on SnapshotInfoList but
+ * we convert to the block layer's native QEMUSnapshotInfo for now.
+ */
+ for (elem = info->snapshots; elem; elem = elem->next) {
+ QEMUSnapshotInfo sn = {
+ .vm_state_size = elem->value->vm_state_size,
+ .date_sec = elem->value->date_sec,
+ .date_nsec = elem->value->date_nsec,
+ .vm_clock_nsec = elem->value->vm_clock_sec * 1000000000ULL +
+ elem->value->vm_clock_nsec,
+ };
+
+ pstrcpy(sn.id_str, sizeof(sn.id_str), elem->value->id);
+ pstrcpy(sn.name, sizeof(sn.name), elem->value->name);
+ printf("%s\n", bdrv_snapshot_dump(buf, sizeof(buf), &sn));
+ }
+ }
+}
+
+static void dump_human_image_info_list(ImageInfoList *list)
+{
+ ImageInfoList *elem;
+ bool delim = false;
+
+ for (elem = list; elem; elem = elem->next) {
+ if (delim) {
+ printf("\n");
+ }
+ delim = true;
+
+ dump_human_image_info(elem->value);
+ }
}
-enum {OPTION_OUTPUT = 256};
+static gboolean str_equal_func(gconstpointer a, gconstpointer b)
+{
+ return strcmp(a, b) == 0;
+}
+
+/**
+ * Open an image file chain and return an ImageInfoList
+ *
+ * @filename: topmost image filename
+ * @fmt: topmost image format (may be NULL to autodetect)
+ * @chain: true - enumerate entire backing file chain
+ * false - only topmost image file
+ *
+ * Returns a list of ImageInfo objects or NULL if there was an error opening an
+ * image file. If there was an error a message will have been printed to
+ * stderr.
+ */
+static ImageInfoList *collect_image_info_list(const char *filename,
+ const char *fmt,
+ bool chain)
+{
+ ImageInfoList *head = NULL;
+ ImageInfoList **last = &head;
+ GHashTable *filenames;
+
+ filenames = g_hash_table_new_full(g_str_hash, str_equal_func, NULL, NULL);
+
+ while (filename) {
+ BlockDriverState *bs;
+ ImageInfo *info;
+ ImageInfoList *elem;
+
+ if (g_hash_table_lookup_extended(filenames, filename, NULL, NULL)) {
+ error_report("Backing file '%s' creates an infinite loop.",
+ filename);
+ goto err;
+ }
+ g_hash_table_insert(filenames, (gpointer)filename, NULL);
+
+ bs = bdrv_new_open(filename, fmt, BDRV_O_FLAGS | BDRV_O_NO_BACKING,
+ false);
+ if (!bs) {
+ goto err;
+ }
+
+ info = g_new0(ImageInfo, 1);
+ collect_image_info(bs, info, filename, fmt);
+ collect_snapshots(bs, info);
+
+ elem = g_new0(ImageInfoList, 1);
+ elem->value = info;
+ *last = elem;
+ last = &elem->next;
+
+ bdrv_delete(bs);
+
+ filename = fmt = NULL;
+ if (chain) {
+ if (info->has_full_backing_filename) {
+ filename = info->full_backing_filename;
+ } else if (info->has_backing_filename) {
+ filename = info->backing_filename;
+ }
+ if (info->has_backing_filename_format) {
+ fmt = info->backing_filename_format;
+ }
+ }
+ }
+ g_hash_table_destroy(filenames);
+ return head;
+
+err:
+ qapi_free_ImageInfoList(head);
+ g_hash_table_destroy(filenames);
+ return NULL;
+}
+
+enum {
+ OPTION_OUTPUT = 256,
+ OPTION_BACKING_CHAIN = 257,
+};
typedef enum OutputFormat {
OFORMAT_JSON,
@@ -1260,9 +1397,9 @@ static int img_info(int argc, char **argv)
{
int c;
OutputFormat output_format = OFORMAT_HUMAN;
+ bool chain = false;
const char *filename, *fmt, *output;
- BlockDriverState *bs;
- ImageInfo *info;
+ ImageInfoList *list;
fmt = NULL;
output = NULL;
@@ -1272,6 +1409,7 @@ static int img_info(int argc, char **argv)
{"help", no_argument, 0, 'h'},
{"format", required_argument, 0, 'f'},
{"output", required_argument, 0, OPTION_OUTPUT},
+ {"backing-chain", no_argument, 0, OPTION_BACKING_CHAIN},
{0, 0, 0, 0}
};
c = getopt_long(argc, argv, "f:h",
@@ -1290,6 +1428,9 @@ static int img_info(int argc, char **argv)
case OPTION_OUTPUT:
output = optarg;
break;
+ case OPTION_BACKING_CHAIN:
+ chain = true;
+ break;
}
}
if (optind >= argc) {
@@ -1306,27 +1447,25 @@ static int img_info(int argc, char **argv)
return 1;
}
- bs = bdrv_new_open(filename, fmt, BDRV_O_FLAGS | BDRV_O_NO_BACKING, false);
- if (!bs) {
+ list = collect_image_info_list(filename, fmt, chain);
+ if (!list) {
return 1;
}
- info = g_new0(ImageInfo, 1);
- collect_image_info(bs, info, filename, fmt);
-
switch (output_format) {
case OFORMAT_HUMAN:
- dump_human_image_info(info);
- dump_snapshots(bs);
+ dump_human_image_info_list(list);
break;
case OFORMAT_JSON:
- collect_snapshots(bs, info);
- dump_json_image_info(info);
+ if (chain) {
+ dump_json_image_info_list(list);
+ } else {
+ dump_json_image_info(list->value);
+ }
break;
}
- qapi_free_ImageInfo(info);
- bdrv_delete(bs);
+ qapi_free_ImageInfoList(list);
return 0;
}
--
1.7.11.7
^ permalink raw reply related [flat|nested] 5+ messages in thread* [Qemu-devel] [PATCH v3 2/2] qemu-iotests: Add 043 backing file chain infinite loop test
2012-10-17 12:02 [Qemu-devel] [PATCH v3 0/2] qemu-img: Add --backing-chain option to info command Stefan Hajnoczi
2012-10-17 12:02 ` [Qemu-devel] [PATCH v3 1/2] " Stefan Hajnoczi
@ 2012-10-17 12:02 ` Stefan Hajnoczi
2012-10-17 14:47 ` [Qemu-devel] [PATCH v3 0/2] qemu-img: Add --backing-chain option to info command Kevin Wolf
2 siblings, 0 replies; 5+ messages in thread
From: Stefan Hajnoczi @ 2012-10-17 12:02 UTC (permalink / raw)
To: qemu-devel; +Cc: Kevin Wolf, kashyap.cv, Benoît Canet, Stefan Hajnoczi
This new test verifies that qemu-img info --backing-chain safely aborts
when an image file has a backing file infinite loop.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
tests/qemu-iotests/043 | 94 ++++++++++++++++++++++++++++++++++++++++++++
tests/qemu-iotests/043.out | 66 +++++++++++++++++++++++++++++++
tests/qemu-iotests/common.rc | 10 +++++
tests/qemu-iotests/group | 1 +
4 files changed, 171 insertions(+)
create mode 100755 tests/qemu-iotests/043
create mode 100644 tests/qemu-iotests/043.out
diff --git a/tests/qemu-iotests/043 b/tests/qemu-iotests/043
new file mode 100755
index 0000000..bf390ac
--- /dev/null
+++ b/tests/qemu-iotests/043
@@ -0,0 +1,94 @@
+#!/bin/bash
+#
+# Test that qemu-img info --backing-chain detects infinite loops
+#
+# Copyright (C) 2012 Red Hat, Inc.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+#
+
+# creator
+owner=stefanha@redhat.com
+
+seq=`basename $0`
+echo "QA output created by $seq"
+
+here=`pwd`
+tmp=/tmp/$$
+status=1 # failure is the default!
+
+_cleanup()
+{
+ _cleanup_test_img
+}
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+# get standard environment, filters and checks
+. ./common.rc
+. ./common.filter
+
+# Any format supporting backing files
+_supported_fmt qcow qcow2 vmdk qed
+_supported_proto generic
+_supported_os Linux
+
+
+size=128M
+_make_test_img $size
+$QEMU_IMG rebase -u -b $TEST_IMG $TEST_IMG
+
+echo
+echo "== backing file references self =="
+_img_info --backing-chain
+
+_make_test_img $size
+mv $TEST_IMG $TEST_IMG.base
+_make_test_img -b $TEST_IMG.base $size
+$QEMU_IMG rebase -u -b $TEST_IMG $TEST_IMG.base
+
+echo
+echo "== parent references self =="
+_img_info --backing-chain
+
+_make_test_img $size
+mv $TEST_IMG $TEST_IMG.1.base
+_make_test_img -b $TEST_IMG.1.base $size
+mv $TEST_IMG $TEST_IMG.2.base
+_make_test_img -b $TEST_IMG.2.base $size
+mv $TEST_IMG $TEST_IMG.3.base
+_make_test_img -b $TEST_IMG.3.base $size
+$QEMU_IMG rebase -u -b $TEST_IMG.2.base $TEST_IMG.1.base
+
+echo
+echo "== ancestor references another ancestor =="
+_img_info --backing-chain
+
+_make_test_img $size
+mv $TEST_IMG $TEST_IMG.1.base
+_make_test_img -b $TEST_IMG.1.base $size
+mv $TEST_IMG $TEST_IMG.2.base
+_make_test_img -b $TEST_IMG.2.base $size
+
+echo
+echo "== finite chain of length 3 (human) =="
+_img_info --backing-chain
+
+echo
+echo "== finite chain of length 3 (json) =="
+_img_info --backing-chain --output=json
+
+# success, all done
+echo "*** done"
+rm -f $seq.full $TEST_IMG.[123].base
+status=0
diff --git a/tests/qemu-iotests/043.out b/tests/qemu-iotests/043.out
new file mode 100644
index 0000000..ad23337
--- /dev/null
+++ b/tests/qemu-iotests/043.out
@@ -0,0 +1,66 @@
+QA output created by 043
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728
+
+== backing file references self ==
+qemu-img: Backing file 'TEST_DIR/t.IMGFMT' creates an infinite loop.
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 backing_file='TEST_DIR/t.IMGFMT.base'
+
+== parent references self ==
+qemu-img: Backing file 'TEST_DIR/t.IMGFMT' creates an infinite loop.
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 backing_file='TEST_DIR/t.IMGFMT.1.base'
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 backing_file='TEST_DIR/t.IMGFMT.2.base'
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 backing_file='TEST_DIR/t.IMGFMT.3.base'
+
+== ancestor references another ancestor ==
+qemu-img: Backing file 'TEST_DIR/t.IMGFMT.2.base' creates an infinite loop.
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 backing_file='TEST_DIR/t.IMGFMT.1.base'
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 backing_file='TEST_DIR/t.IMGFMT.2.base'
+
+== finite chain of length 3 (human) ==
+image: TEST_DIR/t.IMGFMT
+file format: IMGFMT
+virtual size: 128M (134217728 bytes)
+cluster_size: 65536
+backing file: TEST_DIR/t.IMGFMT.2.base
+
+image: TEST_DIR/t.IMGFMT.2.base
+file format: IMGFMT
+virtual size: 128M (134217728 bytes)
+cluster_size: 65536
+backing file: TEST_DIR/t.IMGFMT.1.base
+
+image: TEST_DIR/t.IMGFMT.1.base
+file format: IMGFMT
+virtual size: 128M (134217728 bytes)
+cluster_size: 65536
+
+== finite chain of length 3 (json) ==
+[
+ {
+ "virtual-size": 134217728,
+ "filename": "TEST_DIR/t.IMGFMT",
+ "cluster-size": 65536,
+ "format": "IMGFMT",
+ "backing-filename": "TEST_DIR/t.IMGFMT.2.base",
+ "dirty-flag": false
+ },
+ {
+ "virtual-size": 134217728,
+ "filename": "TEST_DIR/t.IMGFMT.2.base",
+ "cluster-size": 65536,
+ "format": "IMGFMT",
+ "backing-filename": "TEST_DIR/t.IMGFMT.1.base",
+ "dirty-flag": false
+ },
+ {
+ "virtual-size": 134217728,
+ "filename": "TEST_DIR/t.IMGFMT.1.base",
+ "cluster-size": 65536,
+ "format": "IMGFMT",
+ "dirty-flag": false
+ }
+]
+*** done
diff --git a/tests/qemu-iotests/common.rc b/tests/qemu-iotests/common.rc
index d534e94..334534f 100644
--- a/tests/qemu-iotests/common.rc
+++ b/tests/qemu-iotests/common.rc
@@ -145,6 +145,16 @@ _check_test_img()
sed -e 's/qemu-img\: This image format does not support checks/No errors were found on the image./'
}
+_img_info()
+{
+ $QEMU_IMG info "$@" $TEST_IMG 2>&1 | \
+ sed -e "s#$IMGPROTO:$TEST_DIR#TEST_DIR#g" \
+ -e "s#$TEST_DIR#TEST_DIR#g" \
+ -e "s#$IMGFMT#IMGFMT#g" \
+ -e "/^disk size:/ D" \
+ -e "/actual-size/ D"
+}
+
_get_pids_by_name()
{
if [ $# -ne 1 ]
diff --git a/tests/qemu-iotests/group b/tests/qemu-iotests/group
index 66d2ba9..a1b8917 100644
--- a/tests/qemu-iotests/group
+++ b/tests/qemu-iotests/group
@@ -47,3 +47,4 @@
038 rw auto backing
039 rw auto
040 rw auto
+043 rw auto backing
--
1.7.11.7
^ permalink raw reply related [flat|nested] 5+ messages in thread