Commit Graph

1413 Commits

Author SHA1 Message Date
Daniel P. Berrangé
85cd1cc668 migration: use GDateTime for formatting timestamp in snapshot names
The GDateTime APIs provided by GLib avoid portability pitfalls, such
as some platforms where 'struct timeval.tv_sec' field is still 'long'
instead of 'time_t'. When combined with automatic cleanup, GDateTime
often results in simpler code too.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2021-06-14 13:28:50 +01:00
Daniel P. Berrangé
626ff6515d migration: add trace point when vm_stop_force_state fails
This is a critical failure scenario for migration that is hard to
diagnose from existing probes. Most likely it is caused by an error
from bdrv_flush(), but we're not logging the errno anywhere, hence
this new probe.

Reviewed-by: Connor Kuehl <ckuehl@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2021-06-14 13:28:50 +01:00
Rao, Lei
3ba024457f Remove migrate_set_block_enabled in checkpoint
We can detect disk migration in migrate_prepare, if disk migration
is enabled in COLO mode, we can directly report an error.and there
is no need to disable block migration at every checkpoint.

Signed-off-by: Lei Rao <lei.rao@intel.com>
Signed-off-by: Zhang Chen <chen.zhang@intel.com>
Reviewed-by: Li Zhijian <lizhijian@fujitsu.com>
Reviewed-by: Zhang Chen <chen.zhang@intel.com>
Reviewed-by: Lukas Straub <lukasstraub2@web.de>
Tested-by: Lukas Straub <lukasstraub2@web.de>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2021-06-11 10:30:13 +08:00
Peter Xu
a4a571d978 hmp: Add "calc_dirty_rate" and "info dirty_rate" cmds
These two commands are missing when adding the QMP sister commands.
Add them, so developers can play with them easier.

Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Hyman Huang(黄勇) <huangy81@chinatelecom.cn>
Message-Id: <4cc0039fc3ad6145136770cf3b0f056c09a2910b.1623027729.git.huangy81@chinatelecom.cn>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-06-08 20:18:26 +01:00
Hyman Huang(黄勇)
7afa08cd8f migration/dirtyrate: make sample page count configurable
introduce optional sample-pages argument in calc-dirty-rate,
making sample page count per GB configurable so that more
accurate dirtyrate can be calculated.

Signed-off-by: Hyman Huang(黄勇) <huangy81@chinatelecom.cn>
Message-Id: <3103453a3b2796f929269c99a6ad81a9a7f1f405.1623027729.git.huangy81@chinatelecom.cn>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  Wrapped a couple of long lines
2021-06-08 20:18:25 +01:00
Dr. David Alan Gilbert
a59136f3b1 migration/socket: Close the listener at the end
Delay closing the listener until the cleanup hook at the end; mptcp
needs the listener to stay open while the other paths come in.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210421112834.107651-5-dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-06-08 19:36:19 +01:00
Dr. David Alan Gilbert
1df6ddb43b migration: Add cleanup hook for inwards migration
Add a cleanup hook for incoming migration that gets called
at the end as a way for a transport to allow cleanup.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210421112834.107651-4-dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-06-08 19:36:18 +01:00
Li Zhijian
6b8c2eb5c6 migration/rdma: Fix cm event use after free
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Message-Id: <20210602023506.3821293-1-lizhijian@cn.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-06-08 18:55:43 +01:00
Leonardo Bras
7de2e85653 yank: Unregister function when using TLS migration
After yank feature was introduced in migration, whenever migration
is started using TLS, the following error happens in both source and
destination hosts:

(qemu) qemu-kvm: ../util/yank.c:107: yank_unregister_instance:
Assertion `QLIST_EMPTY(&entry->yankfns)' failed.

This happens because of a missing yank_unregister_function() when using
qio-channel-tls.

Fix this by also allowing TYPE_QIO_CHANNEL_TLS object type to perform
yank_unregister_function() in channel_close() and multifd_load_cleanup().

Also, inside migration_channel_connect() and
migration_channel_process_incoming() move yank_register_function() so
it only runs once on a TLS migration.

Fixes: b5eea99ec2 ("migration: Add yank feature", 2021-01-13)
Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1964326
Signed-off-by: Leonardo Bras <leobras.c@gmail.com>
Reviewed-by: Lukas Straub <lukasstraub2@web.de>
Reviewed-by: Peter Xu <peterx@redhat.com>

--
Changes since v2:
- Dropped all references to ioc->master
- yank_register_function() and yank_unregister_function() now only run
  once in a TLS migration.

Changes since v1:
- Cast p->c to QIOChannelTLS into multifd_load_cleanup()
Message-Id: <20210601054030.1153249-1-leobras.c@gmail.com>

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-06-08 18:50:03 +01:00
Stefano Garzarella
d0fb9657a3 docs: fix references to docs/devel/tracing.rst
Commit e50caf4a5c ("tracing: convert documentation to rST")
converted docs/devel/tracing.txt to docs/devel/tracing.rst.

We still have several references to the old file, so let's fix them
with the following command:

  sed -i s/tracing.txt/tracing.rst/ $(git grep -l docs/devel/tracing.txt)

Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210517151702.109066-2-sgarzare@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-06-02 06:51:09 +02:00
Peter Maydell
c5847f5e4e Virtiofs, migration and hmp pull 2021-05-26
Fixes for a loadvm regression from Kevin,
 some virtiofsd cleanups from Vivek and Mahmoud, and
 some RDMA migration fixups from Li.
 
 Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEERfXHG0oMt/uXep+pBRYzHrxb/ecFAmCuiMIACgkQBRYzHrxb
 /edPvxAAimpeeMuCBKPswmuxyAqAoes6FKWNohzCyTCWXEmhvZGFl6SEgMxW0YWh
 DRLfyGUp9CODqNS2oVbj3I7/R5rDvpaqWFJ8GiBH99pc5B+pxYtXjGhjR8JWZ691
 ZvoQsV/nN9dC7woIG5rcus09aPg1X8n8lD2GcV007Gacj3FGGHY6+DOmpfYmrdoG
 QY2OTQ2lMW3l1ACOhtdpWzVKgldYwTDLZsGWuFy+z5b64ijXyImpWa39Hu0HoWdS
 vds5D9GGMfI8kgOlIgsCoC26kre40952VqhOS5ie3axSZt48kufLMUaspiHMiA/B
 mwmrqMrNXoqC7pAWnv8Ur4NjEBlTkPtL4+kIMX0zeqJsRG24Fiee0e42CvNjFixF
 1F419HHKFQPYOvCb/SPLv18gmcyfHdTEbB+yjYIO48ccrPfu/LtTTKG85D1lFw7C
 cy3AWKz6EzYuzs0wtia+0K+5UwOhm2h9Z77kyX5MIfyrb+KWAfupFW6l9NnfmBtp
 +sJBSkIrph6oNmZADx2eSwev+pdlcy0uTOULOiPTF4Iu826LQxoaV9pFcvA+/HXZ
 EbKNrYxDNNYCugLybtULIiFJ8f1i90/UtQlrqAr21deC+gJYliDZScXnzi6lPuv7
 afn4QgMmFLus4ehB0TKcA7QbWL3yyrivXO4TSQNzcZaeXAvHOw0=
 =dIM2
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/dgilbert/tags/pull-migration-20210526a' into staging

Virtiofs, migration and hmp pull 2021-05-26

Fixes for a loadvm regression from Kevin,
some virtiofsd cleanups from Vivek and Mahmoud, and
some RDMA migration fixups from Li.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

# gpg: Signature made Wed 26 May 2021 18:43:30 BST
# gpg:                using RSA key 45F5C71B4A0CB7FB977A9FA90516331EBC5BFDE7
# gpg: Good signature from "Dr. David Alan Gilbert (RH2) <dgilbert@redhat.com>" [full]
# Primary key fingerprint: 45F5 C71B 4A0C B7FB 977A  9FA9 0516 331E BC5B FDE7

* remotes/dgilbert/tags/pull-migration-20210526a:
  migration/rdma: source: poll cm_event from return path
  migration/rdma: destination: create the return patch after the first accept
  migration/rdma: Fix rdma_addrinfo res leaks
  migration/rdma: cleanup rdma in rdma_start_incoming_migration error path
  migration/rdma: Fix cm_event used before being initialized
  tools/virtiofsd/fuse_opt.c: Replaced a malloc with GLib's g_try_malloc
  tools/virtiofsd/buffer.c: replaced a calloc call with GLib's g_try_new0
  virtiofsd: Set req->reply_sent right after sending reply
  virtiofsd: Check EOF before short read
  virtiofsd: Simplify skip byte logic
  virtiofsd: get rid of in_sg_left variable
  virtiofsd: Use iov_discard_front() to skip bytes
  virtiofsd: Get rid of unreachable code in read
  virtiofsd: Check for EINTR in preadv() and retry
  hmp: Fix loadvm to resume the VM on success instead of failure

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-05-27 14:57:01 +01:00
Li Zhijian
e49e49dd73 migration/rdma: source: poll cm_event from return path
source side always blocks if postcopy is only enabled at source side.
users are not able to cancel this migration in this case.

Let source side have chance to cancel this migration

Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Message-Id: <20210525080552.28259-4-lizhijian@cn.fujitsu.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  Typo fix
2021-05-26 18:39:32 +01:00
Li Zhijian
44bcfd45e9 migration/rdma: destination: create the return patch after the first accept
destination side:
$ build/qemu-system-x86_64 -enable-kvm -netdev tap,id=hn0,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown -device e1000,netdev=hn0,mac=50:52:54:00:11:22 -boot c -drive if=none,file=./Fedora-rdma-server-migration.qcow2,id=drive-virtio-disk0 -device virtio-blk-pci,bus=pci.0,addr=0x4,drive=drive-virtio-disk0,id=virtio-disk0 -m 2048 -smp 2 -device piix3-usb-uhci -device usb-tablet -monitor stdio -vga qxl -spice streaming-video=filter,port=5902,disable-ticketing -incoming rdma:192.168.1.10:8888
(qemu) migrate_set_capability postcopy-ram on
(qemu)
dest_init RDMA Device opened: kernel name rocep1s0f0 uverbs device name uverbs0, infiniband_verbs class device path /sys/class/infiniband_verbs/uverbs0, infiniband class device path /sys/class/infiniband/rocep1s0f0, transport: (2) Ethernet
Segmentation fault (core dumped)

 (gdb) bt
 #0  qemu_rdma_accept (rdma=0x0) at ../migration/rdma.c:3272
 #1  rdma_accept_incoming_migration (opaque=0x0) at     ../migration/rdma.c:3986
 #2  0x0000563c9e51f02a in aio_dispatch_handler
     (ctx=ctx@entry=0x563ca0606010, node=0x563ca12b2150) at ../util/aio-posix.c:329
 #3  0x0000563c9e51f752 in aio_dispatch_handlers (ctx=0x563ca0606010) at      ../util/aio-posix.c:372
 #4  aio_dispatch (ctx=0x563ca0606010) at ../util/aio-posix.c:382
 #5  0x0000563c9e4f4d9e in aio_ctx_dispatch (source=<optimized out>,      callback=<optimized out>, user_data=<optimized out>)    at ../util/async.c:306
 #6  0x00007fe96ef3fa9f in g_main_context_dispatch () at      /lib64/libglib-2.0.so.0
 #7  0x0000563c9e4ffeb8 in glib_pollfds_poll () at     ../util/main-loop.c:231
 #8  os_host_main_loop_wait (timeout=12188789) at     ../util/main-loop.c:254
 #9  main_loop_wait (nonblocking=nonblocking@entry=0) at     ../util/main-loop.c:530
 #10 0x0000563c9e3c7211 in qemu_main_loop () at     ../softmmu/runstate.c:725
 #11 0x0000563c9dfd46fe in main (argc=<optimized out>, argv=<optimized     out>, envp=<optimized out>) at ../softmmu/main.c:50

The rdma return path will not be created when qemu incoming is starting
since migrate_copy() is false at that moment, then a  NULL return path
rdma was referenced if the user enabled postcopy later.

Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Message-Id: <20210525080552.28259-3-lizhijian@cn.fujitsu.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-05-26 18:39:32 +01:00
Li Zhijian
f53b450ada migration/rdma: Fix rdma_addrinfo res leaks
rdma_freeaddrinfo() is the reverse operation of rdma_getaddrinfo()

Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20210525080552.28259-2-lizhijian@cn.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-05-26 18:39:32 +01:00
Li Zhijian
4e812d2338 migration/rdma: cleanup rdma in rdma_start_incoming_migration error path
the error path after calling qemu_rdma_dest_init() should do rdma cleanup

Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Message-Id: <20210520081148.17001-1-lizhijian@cn.fujitsu.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-05-26 18:39:32 +01:00
Li Zhijian
efb208dc9c migration/rdma: Fix cm_event used before being initialized
A segmentation fault was triggered when i try to abort a postcopy + rdma
migration.

since rdma_ack_cm_event releases a uninitialized cm_event in these case.

like below:
2496     ret = rdma_get_cm_event(rdma->channel, &cm_event);
2497     if (ret) {
2498         perror("rdma_get_cm_event after rdma_connect");
2499         ERROR(errp, "connecting to destination!");
2500         rdma_ack_cm_event(cm_event); <<<< cause segmentation fault
2501         goto err_rdma_source_connect;
2502     }

Refer to the rdma_get_cm_event() code, cm_event will be
updated/changed only if rdma_get_cm_event() returns 0. So it's okey to
remove the ack in error patch.

Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>

Message-Id: <20210519064740.10828-1-lizhijian@cn.fujitsu.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-05-26 18:39:32 +01:00
Paolo Bonzini
b02629550d replication: move include out of root directory
The replication.h file is included from migration/colo.c and tests/unit/test-replication.c,
so it should be in include/.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-05-26 14:49:46 +02:00
Peter Maydell
9b1e81d1c2 * Replace YAML anchors by extends in the gitlab-CI yaml files
* Many small qtest fixes (e.g. to fix issues discovered by Coverity)
 * Poison more config switches in common code
 * Fix the failing Travis-CI and Cirrus-CI tasks
 -----BEGIN PGP SIGNATURE-----
 
 iQJFBAABCAAvFiEEJ7iIR+7gJQEY8+q5LtnXdP5wLbUFAmCeXFMRHHRodXRoQHJl
 ZGhhdC5jb20ACgkQLtnXdP5wLbUV7g//VRxN74v2pO6zSsSNavYTkMa3jZE1Io3l
 w9lsOr3DM0HIMhyEMwSJsiygj0s8TNanUtFBHfDfo1k1gmZYd5FiM1sB7ZB/sB/S
 9Q9wjmeV2NMG7pcr9zLmiJaEM2LGfGbso44/m0c+gpSyxzg2TeH7sF+38AUZI9/R
 J6/gOzIs4WWdSV4f8kp+YPPQCyOtxZsfxDuk1z1fKsBgXE5iEBUqYyyZUm4gYJkN
 4ALmqc/NVeLszt08qkPHxwXQc488nCJP31psxx6MQ7toKfCAamT07Pp3oi70cakC
 y+HVfsIHc7SxaZyj8sbJCU3LJHwDd8N82ydJUrv216qDffb38fNb+m6y9mcYy2MH
 C25uGe9mucTuTP1WIttC6nCKg/MCgi4PWIzqEhkeKj3TxpTUJJP+BUIfSubV38Gc
 T+XUCNkWWW8sTeRiyE3m9pEZ+gz1MFubaIr/Owephch1SjRYn4zUwJFHHi3I4PY4
 7XjEo8y2M9tKckW3pCfYi+aIDzC1DcRtzvXUGtdemX5xVjTAGlKkFLWl/brdCn2U
 y+JrwrL8cQ3Fy7bXzmK6m9mmhcIW6PcSOBE7RnSESyKzqM5VBSBgnjMqnHcP3FrV
 FYzihTCDcFKy3ELUe3Kbc1TgG/07stQs9xInGXN7ZFsIwadfHgoNVQ6JpOqq1oQa
 fvmLPBhq+a4=
 =QZuG
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/thuth-gitlab/tags/pull-request-2021-05-14' into staging

* Replace YAML anchors by extends in the gitlab-CI yaml files
* Many small qtest fixes (e.g. to fix issues discovered by Coverity)
* Poison more config switches in common code
* Fix the failing Travis-CI and Cirrus-CI tasks

# gpg: Signature made Fri 14 May 2021 12:17:39 BST
# gpg:                using RSA key 27B88847EEE0250118F3EAB92ED9D774FE702DB5
# gpg:                issuer "thuth@redhat.com"
# gpg: Good signature from "Thomas Huth <th.huth@gmx.de>" [full]
# gpg:                 aka "Thomas Huth <thuth@redhat.com>" [full]
# gpg:                 aka "Thomas Huth <huth@tuxfamily.org>" [full]
# gpg:                 aka "Thomas Huth <th.huth@posteo.de>" [unknown]
# Primary key fingerprint: 27B8 8847 EEE0 2501 18F3  EAB9 2ED9 D774 FE70 2DB5

* remotes/thuth-gitlab/tags/pull-request-2021-05-14:
  cirrus.yml: Fix the MSYS2 task
  pc-bios/s390-ccw: Fix inline assembly for older versions of Clang
  tests/qtest/migration-test: Use g_autofree to avoid leaks on error paths
  configure: Poison all current target-specific #defines
  migration: Move populate_vfio_info() into a separate file
  include/sysemu: Poison all accelerator CONFIG switches in common code
  tests: Avoid side effects inside g_assert() arguments
  tests/qtest/rtc-test: Remove pointless NULL check
  tests/qtest/tpm-util.c: Free memory with correct free function
  tests/migration-test: Fix "true" vs true
  tests/qtest/npcm7xx_pwm-test.c: Avoid g_assert_true() for non-test assertions
  tests/qtest/ahci-test.c: Calculate iso_size with 64-bit arithmetic
  util/compatfd.c: Replaced a malloc call with g_malloc.
  libqtest: refuse QTEST_QEMU_BINARY=qemu-kvm
  docs/devel/qgraph: add troubleshooting information
  libqos/qgraph: fix "UNAVAILBLE" typo
  gitlab-ci: Replace YAML anchors by extends (native_test_job)
  gitlab-ci: Replace YAML anchors by extends (native_build_job)
  gitlab-ci: Replace YAML anchors by extends (container_job)
  tests/docker/dockerfiles: Add ccache to containers where it was missing

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-05-14 19:33:23 +01:00
Thomas Huth
43bd0bf30f migration: Move populate_vfio_info() into a separate file
The CONFIG_VFIO switch only works in target specific code. Since
migration/migration.c is common code, the #ifdef does not have
the intended behavior here. Move the related code to a separate
file now which gets compiled via specific_ss instead.

Fixes: 3710586caa ("qapi: Add VFIO devices migration stats in Migration stats")
Message-Id: <20210414112004.943383-3-thuth@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-05-14 12:31:51 +02:00
David Hildenbrand
542147f4e5 migration/ram: Use offset_in_ramblock() in range checks
We never read or write beyond the used_length of memory blocks when
migrating. Make this clearer by using offset_in_ramblock() consistently.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210429112708.12291-11-david@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-05-13 18:21:14 +01:00
David Hildenbrand
c1668bde5c migration/multifd: Print used_length of memory block
We actually want to print the used_length, against which we check.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210429112708.12291-10-david@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-05-13 18:21:14 +01:00
David Hildenbrand
898ba906cc migration/ram: Handle RAM block resizes during postcopy
Resizing while migrating is dangerous and does not work as expected.
The whole migration code works with the usable_length of a ram block and
does not expect this value to change at random points in time.

In the case of postcopy, relying on used_length is racy as soon as the
guest is running. Also, when used_length changes we might leave the
uffd handler registered for some memory regions, reject valid pages
when migrating and fail when sending the recv bitmap to the source.

Resizing can be trigger *after* (but not during) a reset in
ACPI code by the guest
- hw/arm/virt-acpi-build.c:acpi_ram_update()
- hw/i386/acpi-build.c:acpi_ram_update()

Let's remember the original used_length in a separate variable and
use it in relevant postcopy code. Make sure to update it when we resize
during precopy, when synchronizing the RAM block sizes with the source.

Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210429112708.12291-9-david@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-05-13 18:21:14 +01:00
David Hildenbrand
6a23f6399a migration/ram: Simplify host page handling in ram_load_postcopy()
Add two new helper functions. This will come in come handy once we want to
handle ram block resizes while postcopy is active.

Note that ram_block_from_stream() will already print proper errors.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210429112708.12291-8-david@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  dgilbert: Added brackets in host_page_from_ram_block_offset
     to cause uintptr_t to cast the sum, to fix armhf-cross build
2021-05-13 18:21:13 +01:00
David Hildenbrand
cc61c703b6 migration/ram: Discard RAM when growing RAM blocks after ram_postcopy_incoming_init()
In case we grow our RAM after ram_postcopy_incoming_init() (e.g., when
synchronizing the RAM block state with the migration source), the resized
part would not get discarded. Let's perform that when being notified
about a resize while postcopy has been advised, but is not listening
yet. With precopy, the process is as following:

1. VM created
- RAM blocks are created
2. Incomming migration started
- Postcopy is advised
- All pages in RAM blocks are discarded
3. Precopy starts
- RAM blocks are resized to match the size on the migration source.
- RAM pages from precopy stream are loaded
- Uffd handler is registered, postcopy starts listening
4. Guest started, postcopy running
- Pagefaults get resolved, pages get placed

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210429112708.12291-7-david@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-05-13 18:21:13 +01:00
David Hildenbrand
c7c0e72408 migration/ram: Handle RAM block resizes during precopy
Resizing while migrating is dangerous and does not work as expected.
The whole migration code works on the usable_length of ram blocks and does
not expect this to change at random points in time.

In the case of precopy, the ram block size must not change on the source,
after syncing the RAM block list in ram_save_setup(), so as long as the
guest is still running on the source.

Resizing can be trigger *after* (but not during) a reset in
ACPI code by the guest
- hw/arm/virt-acpi-build.c:acpi_ram_update()
- hw/i386/acpi-build.c:acpi_ram_update()

Use the ram block notifier to get notified about resizes. Let's simply
cancel migration and indicate the reason. We'll continue running on the
source. No harm done.

Update the documentation. Postcopy will be handled separately.

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210429112708.12291-5-david@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  Manual merge
2021-05-13 18:21:13 +01:00
Markus Armbruster
372043f389 migration: Drop redundant query-migrate result @blocked
Result @blocked is redundant.  Unfortunately, we realized this too
close to the release to risk dropping it, so we deprecated it
instead, in commit e11ce6c06.

Since it was deprecated from the start, we can delete it without
the customary grace period.  Do so.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210429140424.2802929-1-armbru@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-05-13 18:21:13 +01:00
Kunkun Jiang
ba1b7c812c migration/ram: Optimize ram_save_host_page()
Starting from pss->page, ram_save_host_page() will check every page
and send the dirty pages up to the end of the current host page or
the boundary of used_length of the block. If the host page size is
a huge page, the step "check" will take a lot of time.

It will improve performance to use migration_bitmap_find_dirty().

Tested on Kunpeng 920; VM parameters: 1U 4G (page size 1G)
The time of ram_save_host_page() in the last round of ram saving:
before optimize: 9250us		after optimize: 34us

Signed-off-by: Keqian Zhu <zhukeqian1@huawei.com>
Signed-off-by: Kunkun Jiang <jiangkunkun@huawei.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210316125716.1243-3-jiangkunkun@huawei.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-05-13 18:21:13 +01:00
Kunkun Jiang
23feba906e migration/ram: Reduce unnecessary rate limiting
When the host page is a huge page and something is sent in the
current iteration, migration_rate_limit() should be executed.
If not, it can be omitted.

Signed-off-by: Keqian Zhu <zhukeqian1@huawei.com>
Signed-off-by: Kunkun Jiang <jiangkunkun@huawei.com>
Reviewed-by: David Edmondson <david.edmondson@oracle.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20210316125716.1243-2-jiangkunkun@huawei.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-05-13 18:21:13 +01:00
David Hildenbrand
1a37352277 migrate/ram: remove "ram_bulk_stage" and "fpo_enabled"
The bulk stage is kind of weird: migration_bitmap_find_dirty() will
indicate a dirty page, however, ram_save_host_page() will never save it, as
migration_bitmap_clear_dirty() detects that it is not dirty.

We already fill the bitmap in ram_list_init_bitmaps() with ones, marking
everything dirty - it didn't used to be that way, which is why we needed
an explicit first bulk stage.

Let's simplify: make the bitmap the single source of thuth. Explicitly
handle the "xbzrle_enabled after first round" case.

Regarding XBZRLE (implicitly handled via "ram_bulk_stage = false" right
now), there is now a slight change in behavior:
- Colo: When starting, it will be disabled (was implicitly enabled)
  until the first round actually finishes.
- Free page hinting: When starting, XBZRLE will be disabled (was implicitly
  enabled) until the first round actually finished.
- Snapshots: When starting, XBZRLE will be disabled. We essentially only
  do a single run, so I guess it will never actually get disabled.

Postcopy seems to indirectly disable it in ram_save_page(), so there
shouldn't be really any change.

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Juan Quintela <quintela@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com>
Cc: Peter Xu <peterx@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210216105039.40680-1-david@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-05-13 18:21:13 +01:00
Thomas Huth
2068cabd3f Do not include cpu.h if it's not really necessary
Stop including cpu.h in files that don't need it.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210416171314.2074665-4-thuth@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2021-05-02 17:24:51 +02:00
Thomas Huth
4c386f8064 Do not include sysemu/sysemu.h if it's not really necessary
Stop including sysemu/sysemu.h in files that don't need it.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210416171314.2074665-2-thuth@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2021-05-02 17:24:50 +02:00
Andrey Gruzdev
82ea3e3b99 migration: Rename 'bs' to 'block' in background snapshot code
Rename 'bs' to commonly used 'block' in migration/ram.c background
snapshot code.

Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com>
Reported-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210401092226.102804-5-andrey.gruzdev@virtuozzo.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-04-07 18:37:56 +01:00
Andrey Gruzdev
eeccb99c9d migration: Pre-fault memory before starting background snasphot
This commit solves the issue with userfault_fd WP feature that
background snapshot is based on. For any never poluated or discarded
memory page, the UFFDIO_WRITEPROTECT ioctl() would skip updating
PTE for that page, thereby loosing WP setting for it.

So we need to pre-fault pages for each RAM block to be protected
before making a userfault_fd wr-protect ioctl().

Fixes: 278e2f551a (migration: support
  UFFD write fault processing in ram_save_iterate())
Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com>
Reported-by: David Hildenbrand <david@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210401092226.102804-4-andrey.gruzdev@virtuozzo.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
dgilbert:
  Bodged ifdef __linux__ on ram_write_tracking_prepare, should really
      go in a stub
2021-04-07 18:37:28 +01:00
Andrey Gruzdev
1a8e44a89f migration: Inhibit virtio-balloon for the duration of background snapshot
The same thing as for incoming postcopy - we cannot deal with concurrent
RAM discards when using background snapshot feature in outgoing migration.

Fixes: 8518278a6a (migration: implementation
  of background snapshot thread)
Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com>
Reported-by: David Hildenbrand <david@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210401092226.102804-3-andrey.gruzdev@virtuozzo.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-04-06 18:56:01 +01:00
Andrey Gruzdev
ecb23efea0 migration: Fix missing qemu_fflush() on buffer file in bg_migration_thread
Added missing qemu_fflush() on buffer file holding precopy device state.
Increased initial QIOChannelBuffer allocation to 512KB to avoid reallocs.
Typical configurations often require >200KB for device state and VMDESC.

Fixes: 8518278a6a (migration: implementation
  of background snapshot thread)
Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com>
Message-Id: <20210401092226.102804-2-andrey.gruzdev@virtuozzo.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-04-06 18:56:01 +01:00
Peter Maydell
415fa2fe91 For 6.0 misc patches under my radar.
V2:
  - "tests: Add tests for yank with the chardev-change case" updated
  - drop the readthedoc theme patch
 -----BEGIN PGP SIGNATURE-----
 
 iQJQBAABCAA6FiEEh6m9kz+HxgbSdvYt2ujhCXWWnOUFAmBltIwcHG1hcmNhbmRy
 ZS5sdXJlYXVAcmVkaGF0LmNvbQAKCRDa6OEJdZac5QzCEACOWNUlT5mTylY52sB4
 RXxt+vFFby6aj/M5/tXv7T4EHShWkycV5kEnGjUKiWQXfHfHRfOur6PXkbTMG5zY
 UBEuVAMWW50O2VQZR51W+kohZxsxNnimK2gnCTNGjDWOiofTFAcDf7Ycfxbg1TYU
 fsO3m/dl9cy1fBgCsm64+61T60DC5W0JRsxoRCR1qr4vbJtXjoYe9i21GMWOr548
 EVZo3XQDe5WYeTRyTpf1lHU0dLPrJqZuKmF6M3IQWXG7+ns7iMA0v/STmwsBwqSr
 W6vygj2vPKAi1b1X1z/t/IGXP7mOtTZMUZWxhdOcxqEgYyP4rZji02U33CCd0fCi
 wbD8VOmwvtqPeEHXu/b/dhpacgHis1w8jyJspAcW0MIpFJ+1mn+xtWnmMUlA2cOS
 Vmgirinycsim9TKA+jS3vTwT+/wwzqtWUY267m09tVhJwxvGOXQH1i+mlRRLoNcs
 2vf5iWanRbZgFJme8UYtqYB96pWIJjMa1FkMexJgK3VXgMA+Rjkr4MqIyuPoquyp
 /3PgoUU1LUmGh8F+mi8m88tpdgad6iM+UWXeRALsP7UFvP1Psjz8f6Fhh8uBeE7E
 wsdBsdTwwZ3zgLD4DxjpcZdLM+G7PT0nbeodnPWRuwebsYt3FymoCdmkS1CEn9ZT
 kbQxdeJhTa7QoacZUmQSAoXO6g==
 =UwXe
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/marcandre/tags/for-6.0-pull-request' into staging

For 6.0 misc patches under my radar.

V2:
 - "tests: Add tests for yank with the chardev-change case" updated
 - drop the readthedoc theme patch

# gpg: Signature made Thu 01 Apr 2021 12:54:52 BST
# gpg:                using RSA key 87A9BD933F87C606D276F62DDAE8E10975969CE5
# gpg:                issuer "marcandre.lureau@redhat.com"
# gpg: Good signature from "Marc-André Lureau <marcandre.lureau@redhat.com>" [full]
# gpg:                 aka "Marc-André Lureau <marcandre.lureau@gmail.com>" [full]
# Primary key fingerprint: 87A9 BD93 3F87 C606 D276  F62D DAE8 E109 7596 9CE5

* remotes/marcandre/tags/for-6.0-pull-request:
  tests: Add tests for yank with the chardev-change case
  chardev: Fix yank with the chardev-change case
  chardev/char.c: Always pass id to chardev_new
  chardev/char.c: Move object_property_try_add_child out of chardev_new
  yank: Always link full yank code
  yank: Remove dependency on qiochannel
  docs: simplify each section title
  dbus-vmstate: Increase the size of input stream buffer used during load
  util: fix use-after-free in module_load_one

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-04-01 17:08:48 +01:00
Lukas Straub
1a92d6d500 yank: Remove dependency on qiochannel
Remove dependency on qiochannel by removing yank_generic_iochannel and
letting migration and chardev use their own yank function for
iochannel.

Signed-off-by: Lukas Straub <lukasstraub2@web.de>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20ff143fc2db23e27cd41d38043e481376c9cec1.1616521341.git.lukasstraub2@web.de>
2021-04-01 15:27:44 +04:00
Jessica Clarke
76f67bac79 meson: Propagate gnutls dependency to migration
Commit 3eacf70bb5 neglected to fix this
for softmmu configs, which pull in migration's use of gnutls.

This fixes the following compilation failure on Arm-based Macs:

  In file included from migration/multifd.c:23:
  In file included from migration/tls.h:25:
  In file included from include/io/channel-tls.h:26:
  In file included from include/crypto/tlssession.h:24:
  include/crypto/tlscreds.h:28:10: fatal error: 'gnutls/gnutls.h' file not found
  #include <gnutls/gnutls.h>
           ^~~~~~~~~~~~~~~~~
  1 error generated.

(as well as for channel.c and tls.c)

Signed-off-by: Jessica Clarke <jrtc27@jrtc27.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20210320171221.37437-1-jrtc27@jrtc27.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-04-01 09:40:45 +02:00
Vladimir Sementsov-Ogievskiy
4290b4834c migration/block-dirty-bitmap: make incoming disabled bitmaps busy
Incoming enabled bitmaps are busy, because we do
bdrv_dirty_bitmap_create_successor() for them. But disabled bitmaps
being migrated are not marked busy, and user can remove them during the
incoming migration. Then we may crash in cancel_incoming_locked() when
try to remove the bitmap that was already removed by user, like this:

 #0  qemu_mutex_lock_impl (mutex=0x5593d88c50d1, file=0x559680554b20
   "../block/dirty-bitmap.c", line=64) at ../util/qemu-thread-posix.c:77
 #1  bdrv_dirty_bitmaps_lock (bs=0x5593d88c0ee9)
   at ../block/dirty-bitmap.c:64
 #2  bdrv_release_dirty_bitmap (bitmap=0x5596810e9570)
   at ../block/dirty-bitmap.c:362
 #3  cancel_incoming_locked (s=0x559680be8208 <dbm_state+40>)
   at ../migration/block-dirty-bitmap.c:918
 #4  dirty_bitmap_load (f=0x559681d02b10, opaque=0x559680be81e0
   <dbm_state>, version_id=1) at ../migration/block-dirty-bitmap.c:1194
 #5  vmstate_load (f=0x559681d02b10, se=0x559680fb5810)
   at ../migration/savevm.c:908
 #6  qemu_loadvm_section_part_end (f=0x559681d02b10,
   mis=0x559680fb4a30) at ../migration/savevm.c:2473
 #7  qemu_loadvm_state_main (f=0x559681d02b10, mis=0x559680fb4a30)
   at ../migration/savevm.c:2626
 #8  postcopy_ram_listen_thread (opaque=0x0)
   at ../migration/savevm.c:1871
 #9  qemu_thread_start (args=0x5596817ccd10)
   at ../util/qemu-thread-posix.c:521
 #10 start_thread () at /lib64/libpthread.so.0
 #11 clone () at /lib64/libc.so.6

Note bs pointer taken from bitmap: it's definitely bad aligned. That's
because we are in use after free, bitmap is already freed.

So, let's make disabled bitmaps (being migrated) busy during incoming
migration.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20210322094906.5079-2-vsementsov@virtuozzo.com>
2021-03-24 13:41:19 +00:00
Daniel P. Berrangé
cbde7be900 migrate: remove QMP/HMP commands for speed, downtime and cache size
The generic 'migrate_set_parameters' command handle all types of param.

Only the QMP commands were documented in the deprecations page, but the
rationale for deprecating applies equally to HMP, and the replacements
exist. Furthermore the HMP commands are just shims to the QMP commands,
so removing the latter breaks the former unless they get re-implemented.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2021-03-18 09:22:55 +00:00
Mahmoud Mandour
373969507a migration: Replaced qemu_mutex_lock calls with QEMU_LOCK_GUARD
Replaced various qemu_mutex_lock calls and their respective
qemu_mutex_unlock calls with QEMU_LOCK_GUARD macro. This simplifies
the code by eliminating the respective qemu_mutex_unlock calls.

Signed-off-by: Mahmoud Mandour <ma.mandourr@gmail.com>
Message-Id: <20210311031538.5325-7-ma.mandourr@gmail.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-03-15 20:01:55 +00:00
Hao Wang
fca676429c migration/tls: add error handling in multifd_tls_handshake_thread
If any error happens during multifd send thread creating (e.g. channel broke
because new domain is destroyed by the dst), multifd_tls_handshake_thread
may exit silently, leaving main migration thread hanging (ram_save_setup ->
multifd_send_sync_main -> qemu_sem_wait(&p->sem_sync)).
Fix that by adding error handling in multifd_tls_handshake_thread.

Signed-off-by: Hao Wang <wanghao232@huawei.com>
Message-Id: <20210209104237.2250941-3-wanghao232@huawei.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Chuan Zheng <zhengchuan@huawei.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-03-15 20:01:55 +00:00
Hao Wang
a339149afa migration/tls: fix inverted semantics in multifd_channel_connect
Function multifd_channel_connect() return "true" to indicate failure,
which is rather confusing. Fix that.

Signed-off-by: Hao Wang <wanghao232@huawei.com>
Message-Id: <20210209104237.2250941-2-wanghao232@huawei.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Chuan Zheng <zhengchuan@huawei.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-03-15 20:01:55 +00:00
Peter Krempa
6e9f21a2aa migration: dirty-bitmap: Allow control of bitmap persistence
Bitmap's source persistence is transported over the migration stream and
the destination mirrors it. In some cases the destination might want to
persist bitmaps which are not persistent on the source (e.g. the result
of merging bitmaps from a number of layers on the source when migrating
into a squashed image) but currently it would need to create another set
of persistent bitmaps and merge them.

This patch adds a 'transform' property to the alias map which allows
overriding the persistence of migrated bitmaps both on the source and
destination sides.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Message-Id: <b20afb675917b86f6359ac3591166ac6d4233573.1613150869.git.pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: grammar tweaks, drop dead conditional]
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-02-12 15:24:36 -06:00
Peter Krempa
0d1e450c7b migration: dirty-bitmap: Use struct for alias map inner members
Currently the alias mapping hash stores just strings of the target
objects internally. In further patches we'll be adding another member
which will need to be stored in the map so pass a copy of the whole
BitmapMigrationBitmapAlias QAPI struct into the map.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Message-Id: <fc5f27e1fe16cb75e08a248c2d938de3997b9bfb.1613150869.git.pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: adjust long lines]
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-02-12 14:50:55 -06:00
Stefan Reiter
e846b74650 migration: only check page size match if RAM postcopy is enabled
Postcopy may also be advised for dirty-bitmap migration only, in which
case the remote page size will not be available and we'll instead read
bogus data, blocking migration with a mismatch error if the VM uses
hugepages.

Fixes: 58110f0acb ("migration: split common postcopy out of ram postcopy")
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
Message-Id: <20210204163522.13291-1-s.reiter@proxmox.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-02-08 11:19:52 +00:00
Daniel P. Berrangé
0f0d83a456 migration: introduce snapshot-{save, load, delete} QMP commands
savevm, loadvm and delvm are some of the few HMP commands that have never
been converted to use QMP. The reasons for the lack of conversion are
that they blocked execution of the event thread, and the semantics
around choice of disks were ill-defined.

Despite this downside, however, libvirt and applications using libvirt
have used these commands for as long as QMP has existed, via the
"human-monitor-command" passthrough command. IOW, while it is clearly
desirable to be able to fix the problems, they are not a blocker to
all real world usage.

Meanwhile there is a need for other features which involve adding new
parameters to the commands. This is possible with HMP passthrough, but
it provides no reliable way for apps to introspect features, so using
QAPI modelling is highly desirable.

This patch thus introduces new snapshot-{load,save,delete} commands to
QMP that are intended to replace the old HMP counterparts. The new
commands are given different names, because they will be using the new
QEMU job framework and thus will have diverging behaviour from the HMP
originals. It would thus be misleading to keep the same name.

While this design uses the generic job framework, the current impl is
still blocking. The intention that the blocking problem is fixed later.
None the less applications using these new commands should assume that
they are asynchronous and thus wait for the job status change event to
indicate completion.

In addition to using the job framework, the new commands require the
caller to be explicit about all the block device nodes used in the
snapshot operations, with no built-in default heuristics in use.

Note that the existing "query-named-block-nodes" can be used to query
what snapshots currently exist for block nodes.

Acked-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210204124834.774401-13-berrange@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  dgilbert: removed tests for now, the output ordering isn't
deterministic
2021-02-08 11:19:52 +00:00
Daniel P. Berrangé
bef7e9e2c7 migration: introduce a delete_snapshot wrapper
Make snapshot deletion consistent with the snapshot save
and load commands by using a wrapper around the blockdev
layer. The main difference is that we get upfront validation
of the passed in device list (if any).

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210204124834.774401-10-berrange@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-02-08 11:19:51 +00:00
Daniel P. Berrangé
f1a9fcdd01 migration: wire up support for snapshot device selection
Modify load_snapshot/save_snapshot to accept the device list and vmstate
node name parameters previously added to the block layer.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210204124834.774401-9-berrange@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-02-08 11:19:51 +00:00
Daniel P. Berrangé
f781f84189 migration: control whether snapshots are ovewritten
The traditional HMP "savevm" command will overwrite an existing snapshot
if it already exists with the requested name. This new flag allows this
to be controlled allowing for safer behaviour with a future QMP command.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210204124834.774401-8-berrange@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-02-08 11:19:51 +00:00