Markus Armbruster c42e8742f5 block: Use JSON null instead of "" to disable backing file ... BlockdevRef is an alternate of BlockdevOptions (inline definition) and str (reference to an existing block device by name). BlockdevRef value "" is special: "no block device should be referenced." It's actually interpreted that way in just one place: optional member @backing of COW formats. Semantics: * Present means "use this block device" as backing storage * Absent means "default to the one stored in the image" * Except "" means "don't use backing storage at all" The first two are perfectly normal: when the parameter is absent, it defaults to an implied value, but the value's meaning is the same. The third one overloads the parameter with a second meaning. The overloading is *implicit*, i.e. it's not visible in the types. Works here, because "" is not a value block device ID. Pressing argument values the schema accepts, but are semantically invalid, into service to mean "do something else entirely" is not general, as suitable invalid values need not exist. I also find it ugly. To clean this up, we could add a separate flag argument to suppress @backing, or add a distinct value to @backing. This commit implements the latter: add JSON null to the values of @backing, deprecate "". Because we're so close to the 2.10 freeze, implement it in the stupidest way possible: have qmp_blockdev_add() rewrite null to "" before anything else can see the null. Works, because BlockdevRef occurs only within arguments of blockdev-add. The proper way to do it would be rewriting "" to null, preferably in a cleaner way, but that requires fixing up code to work with null. Add a TODO comment for that. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Daniel P. Berrange <berrange@redhat.com> Acked-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>		2017-07-24 13:35:11 +02:00
..
acpi-test-data	i386/acpi: update expected acpi files	2017-07-03 22:42:36 +03:00
data	test-qga: add test for guest-get-osinfo	2017-07-18 05:49:01 -05:00
docker	docker: install clang since Shippable setup_ve() verify it is available	2017-07-18 10:58:36 +01:00
guest-debug
image-fuzzer
libqos	libqos: add virtio used ring support	2017-06-30 11:03:45 +01:00
migration	tests: introduce a framework for testing migration performance	2016-07-22 13:23:39 +05:30
multiboot	tests: Avoid non-portable 'echo -ARG'	2017-07-11 17:45:00 +02:00
qapi-schema	qapi: Introduce a first class 'null' type	2017-07-24 13:35:11 +02:00
qemu-iotests	block: Use JSON null instead of "" to disable backing file	2017-07-24 13:35:11 +02:00
rocker	tests: Avoid non-portable 'echo -ARG'	2017-07-11 17:45:00 +02:00
tcg	Replace 'struct ucontext' with 'ucontext_t' type	2017-07-20 10:10:28 +01:00
vmstate-static-checker-data
.gitignore	tests: crypto: add hmac speed benchmark support	2017-07-19 10:11:05 +01:00
ac97-test.c
acpi-utils.c	tests: Move reusable ACPI code into a utility file	2017-03-02 07:14:27 +02:00
acpi-utils.h	hw/i386: Use Rev3 FADT (ACPI 2.0) instead of Rev1 to improve guest OS support.	2017-05-03 12:29:40 +02:00
ahci-test.c	tests/ahci-test: Be mean with RAM	2017-07-18 11:47:57 -04:00
atomic_add-bench.c	tests: add atomic_add-bench	2016-10-26 08:29:01 -07:00
benchmark-crypto-cipher.c	tests: crypto: add cipher speed benchmark support	2017-07-19 10:11:05 +01:00
benchmark-crypto-hash.c	tests: crypto: add hash speed benchmark support	2017-07-19 10:11:05 +01:00
benchmark-crypto-hmac.c	tests: crypto: add hmac speed benchmark support	2017-07-19 10:11:05 +01:00
bios-tables-test.c	pci, virtio, vhost: fixes	2017-05-18 10:01:08 +01:00
boot-order-test.c
boot-sector.c	tests/boot-sector: Increase time-out to 90 seconds	2016-10-14 10:06:47 +11:00
boot-sector.h	tests/boot-sector: Use mkstemp() to create a unique file name	2016-10-14 10:06:47 +11:00
boot-serial-test.c	boot-serial-test: use -no-shutdown	2017-03-24 13:39:50 +00:00
check-block.sh	tests: allow to specify list of formats to test for check-block.sh	2016-09-23 13:36:09 +02:00
check-qdict.c	tests/qdict: check more get_try_int() cases	2017-06-20 14:31:33 +02:00
check-qjson.c	qapi: Separate type QNull from QObject	2017-07-24 13:35:11 +02:00
check-qlist.c	tests: remove /{qnum, qlist, dict}/destroy test	2017-06-20 14:31:31 +02:00
check-qnull.c	qapi: Use QNull for a more regular visit_type_null()	2017-07-24 13:35:11 +02:00
check-qnum.c	qnum: add uint type	2017-06-20 14:31:31 +02:00
check-qom-interface.c	tests: fix check-qom-interface leaks	2016-09-08 17:57:32 +04:00
check-qom-proplist.c	qom: Fix ambiguous path detection when ambiguous=NULL	2017-07-17 15:41:30 -03:00
check-qstring.c	tests: remove /{qnum, qlist, dict}/destroy test	2017-06-20 14:31:31 +02:00
crypto-tls-x509-helpers.c
crypto-tls-x509-helpers.h	clean-up: removed duplicate #includes	2016-10-28 18:17:24 +03:00
device-introspect-test.c	qmp: Include parent type on 'qom-list-types' output	2017-07-17 15:41:30 -03:00
display-vga-test.c	qtest: add display-vga-test to ppc64	2017-01-31 10:10:13 +11:00
drive_del-test.c	tests: Use null-co:// instead of /dev/null as the dummy image	2017-05-11 11:08:40 +02:00
ds1338-test.c
e1000-test.c	tests: fix e1000-test leak	2017-03-01 11:51:28 +04:00
e1000e-test.c	tests: fix e1000e leaks	2017-03-01 11:51:28 +04:00
eepro100-test.c	tests: fix eepro100-test leak	2017-03-01 11:51:05 +04:00
endianness-test.c	tests: fix endianness-test leaks	2017-03-01 00:09:28 +04:00
es1370-test.c
fdc-test.c	fdc-test: Avoid deprecated 'change' command	2017-05-09 09:14:40 +02:00
fw_cfg-test.c
hd-geo-test.c	tests: fix hd-geo-test leaks	2017-03-01 11:51:04 +04:00
i440fx-test.c	tests: fix i440fx-test leaks	2017-03-01 11:51:28 +04:00
i82801b11-test.c
ide-test.c	ide-test: check return of fwrite	2017-06-04 18:42:55 +03:00
intel-hda-test.c
io-channel-helpers.c
io-channel-helpers.h
ioh3420-test.c
iothread.c	aio: introduce aio_co_schedule and aio_co_wake	2017-02-21 11:14:07 +00:00
iothread.h	aio: introduce aio_co_schedule and aio_co_wake	2017-02-21 11:14:07 +00:00
ipmi-bt-test.c	tests: fix ipmi-bt-test leak	2017-03-01 11:51:05 +04:00
ipmi-kcs-test.c	tests: fix ipmi-kcs-test leak	2017-03-01 11:51:05 +04:00
ipoctal232-test.c
ivshmem-test.c	qtest: add ivshmem-test for ppc64	2017-01-31 10:10:13 +11:00
libqtest.c	tests/libqtest: Print error instead of aborting when env variable is missing	2017-06-04 18:42:55 +03:00
libqtest.h	libqtest: Add a generic function to run a callback function for every machine	2017-04-26 14:42:31 +01:00
m25p80-test.c	aspeed/smc: extend tests for Command mode	2017-01-20 11:15:08 +00:00
m48t59-test.c
Makefile.include	tests: Handle $RANDOM not being supported by the shell	2017-07-20 15:00:00 +01:00
megasas-test.c	megasas: always store SCSIRequest* into MegasasCmd	2017-06-15 11:04:05 +02:00
ne2000-test.c
numa-test.c	numa-test: fix query-cpus leaks	2017-05-30 16:09:48 -03:00
nvme-test.c	tests: Use null-co:// instead of /dev/null as the dummy image	2017-05-11 11:08:40 +02:00
pc-cpu-test.c	libqtest: Add a generic function to run a callback function for every machine	2017-04-26 14:42:31 +01:00
pcnet-test.c
pkix_asn1_tab.c	qtest: fix make check complaint in crypto module	2016-10-19 10:09:24 +01:00
pnv-xscom-test.c	powernv: Don't test POWER9 CPU yet	2017-03-03 11:30:59 +11:00
postcopy-test.c	chardev: move headers to include/chardev	2017-06-02 11:33:52 +04:00
prom-env-test.c	tests/prom-env: Enable the test for the sun4u machine, too	2017-02-28 09:03:39 +03:00
ptimer-test-stubs.c	tests: fix ptimer leaks	2017-03-01 00:09:28 +04:00
ptimer-test.c	tests: fix ptimer leaks	2017-03-01 00:09:28 +04:00
ptimer-test.h	tests: ptimer: Change the copyright comment	2016-10-24 16:26:53 +01:00
pvpanic-test.c	tests: fix qmp response leak	2017-03-01 00:09:28 +04:00
pxe-test.c	tests/boot-sector: Use mkstemp() to create a unique file name	2016-10-14 10:06:47 +11:00
q35-test.c	tests/q35-test: add TSEG size checks	2017-06-16 18:44:55 +03:00
qemu-iotests-quick.sh
qht-bench.c	exec: [tcg] Use different TBs according to the vCPU's dynamic tracing state	2017-07-17 13:11:05 +01:00
qmp-test.c	qapi: Drop unused non-strict qobject input visitor	2017-03-05 09:14:19 +01:00
qom-test.c	libqtest: Add a generic function to run a callback function for every machine	2017-04-26 14:42:31 +01:00
rcutorture.c
rtas-test.c	tests: don't check if qtest_spapr_boot() returns NULL	2016-10-28 09:36:58 +11:00
rtc-test.c	qtest: add rtc periodic timer test	2017-06-06 20:18:35 +02:00
rtl8139-test.c	libqos: Change PCI accessors to take opaque BAR handle	2016-10-28 09:38:27 +11:00
spapr-phb-test.c	spapr: Improved placement of PCI host bridges in guest memory map	2016-10-16 12:04:15 +11:00
tco-test.c	tests: fix tco-test leaks	2017-03-01 11:51:25 +04:00
test-aio-multithread.c	cpus: define QEMUTimerListNotifyCB for QEMU system emulation	2017-03-14 13:28:29 +01:00
test-aio.c	cpus: define QEMUTimerListNotifyCB for QEMU system emulation	2017-03-14 13:28:29 +01:00
test-arm-mptimer.c	tests: Add tests for the ARM MPTimer	2016-10-24 16:26:54 +01:00
test-base64.c
test-bitcnt.c	tests: New test-bitcnt	2017-01-10 08:49:59 -08:00
test-bitops.c
test-blockjob-txn.c	blockjob: strengthen a bit test-blockjob-txn	2017-05-24 16:38:51 -04:00
test-blockjob.c	blockjob: introduce block_job_early_fail	2017-05-24 16:38:51 -04:00
test-bufferiszero.c	cutils: Add test for buffer_is_zero	2016-09-13 19:13:32 +02:00
test-char.c	test-char: add hotswap test	2017-07-14 11:04:34 +02:00
test-clone-visitor.c	tests/qapi-schema: Avoid 'str' in alternate test cases	2017-05-31 16:04:05 +02:00
test-coroutine.c	test-coroutine: test qemu_coroutine_entered()	2016-09-28 17:11:23 +01:00
test-crypto-afsplit.c
test-crypto-block.c	block: pass option prefix down to crypto layer	2017-07-11 17:44:56 +02:00
test-crypto-cipher.c	crypto: add 3des-ede support when using libgcrypt/nettle	2016-12-21 14:26:26 +00:00
test-crypto-hash.c	crypto: fix initialization of crypto in tests	2016-10-19 10:23:55 +01:00
test-crypto-hmac.c	crypto: add HMAC algorithms testcases	2016-12-22 09:24:59 +00:00
test-crypto-ivgen.c
test-crypto-pbkdf.c	crypto: support more hash algorithms for pbkdf	2016-09-19 16:30:45 +01:00
test-crypto-secret.c
test-crypto-tlscredsx509.c
test-crypto-tlssession.c
test-crypto-xts.c
test-cutils.c	util/cutils: Change qemu_strtosz*() from int64_t to uint64_t	2017-02-23 20:35:36 +01:00
test-filter-mirror.c	tests: fix qmp response leak	2017-03-01 00:09:28 +04:00
test-filter-redirector.c	tests: fix qmp response leak	2017-03-01 00:09:28 +04:00
test-hbitmap.c	tests: add hbitmap iter test	2017-07-11 17:44:57 +02:00
test-hmp.c	hmp: add hmp analogue for qmp-chardev-change	2017-07-14 11:04:34 +02:00
test-int128.c	int128: Use __int128 if available	2016-10-26 08:29:00 -07:00
test-io-channel-buffer.c
test-io-channel-command.c	tests: fix leaks in test-io-channel-command	2017-03-01 00:09:28 +04:00
test-io-channel-file.c
test-io-channel-socket.c	sockets: Limit SocketAddressLegacy to external interfaces	2017-05-09 09:14:40 +02:00
test-io-channel-tls.c	io: change the QIOTask callback signature	2017-01-23 15:32:18 +00:00
test-io-task.c	io: fix possible double free of task error object	2017-01-26 10:26:18 +00:00
test-iov.c	tests: fix test-iov leaks	2016-09-08 17:57:32 +04:00
test-keyval.c	tests: Remove test cases for alternates of 'number' and 'int'	2017-06-19 14:56:29 +02:00
test-logging.c	test-logging: don't hard-code paths in /tmp	2016-08-19 12:44:11 +01:00
test-mul64.c
test-netfilter.c
test-opts-visitor.c	qapi: Fix QemuOpts visitor regression on unvisited input	2017-03-22 19:24:34 +01:00
test-qapi-util.c	qapi: New parse_qapi_name()	2017-03-07 16:07:47 +01:00
test-qdev-global-props.c	test-qdev-global-props: Test global property ordering	2017-07-17 15:41:30 -03:00
test-qdist.c	qdist: return "(empty)" instead of NULL when printing an empty dist	2016-08-03 18:44:56 +02:00
test-qemu-opts.c	qobject: Use simpler QDict/QList scalar insertion macros	2017-05-09 09:13:51 +02:00
test-qga.c	test-qga: add test for guest-get-osinfo	2017-07-18 05:49:01 -05:00
test-qht-par.c
test-qht.c	test-qht: perform lookups under rcu_read_lock	2016-10-06 18:04:13 +02:00
test-qmp-commands.c	qapi: merge QInt and QFloat in QNum	2017-06-20 14:31:31 +02:00
test-qmp-event.c	qapi: merge QInt and QFloat in QNum	2017-06-20 14:31:31 +02:00
test-qobject-input-visitor.c	tests/test-qobject-input-visitor: Drop redundant test	2017-07-24 13:35:11 +02:00
test-qobject-output-visitor.c	qapi: Introduce a first class 'null' type	2017-07-24 13:35:11 +02:00
test-rcu-list.c
test-replication.c	tests: Disable image lock in test-replication	2017-05-11 11:08:41 +02:00
test-shift128.c	host-utils: Implement unsigned quadword left/right shift and unit tests	2017-01-31 10:10:14 +11:00
test-string-input-visitor.c	qapi: Fix string input visitor regression for empty lists	2017-03-21 10:43:01 +01:00
test-string-output-visitor.c	qapi: rename *qmp-*-visitor* to *qobject-*-visitor*	2016-10-25 16:25:48 +02:00
test-thread-pool.c	test-thread-pool: use generic AioContext infrastructure	2017-02-21 11:14:07 +00:00
test-throttle.c	block: remove timer canceling in throttle_config()	2017-07-18 15:14:35 +02:00
test-timed-average.c
test-uuid.c	test-uuid: fix leak	2016-11-11 20:53:23 +08:00
test-visitor-serialization.c	test-visitor-serialization: Pass &error_abort to qobject_from_json()	2017-03-07 16:07:47 +01:00
test-vmstate.c	migration: Move migration.h to migration/	2017-06-13 11:00:45 +02:00
test-write-threshold.c
test-x86-cpuid-compat.c	qapi: merge QInt and QFloat in QNum	2017-06-20 14:31:31 +02:00
test-x86-cpuid.c
test-xbzrle.c	migration: Create migration/xbzrle.h	2017-05-18 18:04:54 +02:00
tmp105-test.c
tpci200-test.c
usb-hcd-ehci-test.c	tests: fix usb-test leaks	2017-03-01 11:51:29 +04:00
usb-hcd-ohci-test.c
usb-hcd-uhci-test.c	tests: Use null-co:// instead of /dev/null as the dummy image	2017-05-11 11:08:40 +02:00
usb-hcd-xhci-test.c	tests: Use null-co:// instead of /dev/null as the dummy image	2017-05-11 11:08:40 +02:00
vhost-user-bridge.c	vhost-user-bridge: fix iov_restore_front() warning	2017-06-08 22:02:36 +03:00
vhost-user-test.c	char: add backend hotswap handler	2017-07-14 11:04:33 +02:00
virtio-9p-test.c	tests/virtio-9p-test: Don't call le*_to_cpus on fields of packed struct	2017-03-27 21:15:31 +02:00
virtio-balloon-test.c
virtio-blk-test.c	tests: fix virtio-blk-test ISR dependence	2017-06-30 11:03:45 +01:00
virtio-console-test.c
virtio-net-test.c	tests: fix virtio-net-test ISR dependence	2017-06-30 11:03:45 +01:00
virtio-rng-test.c	tests: enable virtio tests on SPAPR	2016-10-28 09:36:58 +11:00
virtio-scsi-test.c	tests: fix virtio-scsi-test ISR dependence	2017-06-30 11:03:45 +01:00
virtio-serial-test.c
vmgenid-test.c	vmgenid-test: use boot-sector infrastructure	2017-07-14 17:03:03 +01:00
vmxnet3-test.c
wdt_ib700-test.c