Commit Graph

59 Commits

Author SHA1 Message Date
Marc-André Lureau
f0937ec669 migration: fix a typo
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Fiona Ebner <f.ebner@proxmox.com>
Tested-by: Fiona Ebner <f.ebner@proxmox.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
2024-05-22 17:34:40 -03:00
Marc-André Lureau
3f879f2f31 migration: add "exists" info to load-state-field trace
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Fiona Ebner <f.ebner@proxmox.com>
Tested-by: Fiona Ebner <f.ebner@proxmox.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
2024-05-22 17:34:40 -03:00
Richard Henderson
2027001919 migration: Make VMStateDescription.subsections const
Allow the array of pointers to itself be const.
Propagate this through the copies of this field.

Tested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20231221031652.119827-2-richard.henderson@linaro.org>
2023-12-29 11:17:30 +11:00
Juan Quintela
e9c0eed7c2 qemu-file: Remove _noflush from qemu_file_transferred_noflush()
qemu_file_transferred() don't exist anymore, so we can reuse the name.

Reviewed-by: Fabiano Rosas <farosas@suse.de>
Signed-off-by: Juan Quintela <quintela@redhat.com>

Message-ID: <20231025091117.6342-7-quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2023-10-31 08:44:33 +01:00
Marc-André Lureau
cd4c0da6db migration: set file error on subsection loading
commit 13cde50889 ("vmstate: Return error in case of error") sets
QemuFile error to stop reading from it and report to the caller (checked
by unit tests). We should do the same on subsection loading error.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <20231024084043.2926316-8-marcandre.lureau@redhat.com>
2023-10-30 17:44:03 +01:00
Marc-André Lureau
4d8bdc2ae0 migration: rename vmstate_save_needed->vmstate_section_needed
The function is used on save at this point. The following commits will
use it on load.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <20231024084043.2926316-5-marcandre.lureau@redhat.com>
2023-10-30 17:44:03 +01:00
Peter Xu
579cedf430 migration: Unify and trace vmstate field_exists() checks
For both save/load we actually share the logic on deciding whether a field
should exist.  Merge the checks into a helper and use it for both save and
load.  When doing so, add documentations and reformat the code to make it
much easier to read.

The real benefit here (besides code cleanups) is we add a trace-point for
this; this is a known spot where we can easily break migration
compatibilities between binaries, and this trace point will be critical for
us to identify such issues.

For example, this will be handy when debugging things like:

https://gitlab.com/qemu-project/qemu/-/issues/932

Reviewed-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <20230906204722.514474-1-peterx@redhat.com>
2023-10-04 13:19:47 +02:00
Tejus GK
848a050342 migration: Update error description outside migration.c
A few code paths exist in the source code,where a migration is
marked as failed via MIGRATION_STATUS_FAILED, but the failure happens
outside	of migration.c

In such	cases, an error_report() call is made, however the current
MigrationState is never	updated	with the error description, and	hence
clients	like libvirt never know	the actual reason for the failure.

This patch covers such cases outside of	migration.c and	updates	the
error description at the appropriate places.

Acked-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Tejus GK <tejus.gk@nutanix.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <20231003065538.244752-3-tejus.gk@nutanix.com>
2023-10-04 10:54:40 +02:00
Tejus GK
969298f9d7 migration/vmstate: Introduce vmstate_save_state_with_err
Currently, a few code paths exist in the function vmstate_save_state_v,
which ultimately leads to a migration failure. However, an update in the
current MigrationState for the error description is never done.

vmstate.c somehow doesn't seem to allow	the use	of migrate_set_error due
to some	dependencies for unit tests. Hence, this patch introduces a new
function vmstate_save_state_with_err, which will eventually propagate
the error message to savevm.c where a migrate_set_error	call can be
eventually done.

Acked-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Tejus GK <tejus.gk@nutanix.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <20231003065538.244752-2-tejus.gk@nutanix.com>
2023-10-04 10:54:40 +02:00
Markus Armbruster
7f3de3f02f migration: Clean up local variable shadowing
Local variables shadowing other local variables or parameters make the
code needlessly hard to understand.  Tracked down with -Wshadow=local.
Clean up: delete inner declarations when they are actually redundant,
else rename variables.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Li Zhijian <lizhijian@fujitsu.com>
Message-ID: <20230921121312.1301864-3-armbru@redhat.com>
2023-09-29 08:13:57 +02:00
Juan Quintela
fc95c63b60 qemu-file: Rename qemu_file_transferred_ fast -> noflush
Fast don't say much.  Noflush indicates more clearly that it is like
qemu_file_transferred but without the flush.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20230530183941.7223-2-quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2023-07-26 10:55:56 +02:00
Juan Quintela
6da835d42a qemu-file: Remove total from qemu_file_total_transferred_*()
Function is already quite long.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20230508130909.65420-7-quintela@redhat.com>
2023-05-15 13:46:14 +02:00
Juan Quintela
61abf1ebdc qemu-file: Make total_transferred an uint64_t
Change all the functions that use it.  It was already passed as
uint64_t.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20230504113841.23130-8-quintela@redhat.com>
2023-05-05 02:01:59 +02:00
Dr. David Alan Gilbert
89c5684891 migration: Add canary to VMSTATE_END_OF_LIST
We fairly regularly forget VMSTATE_END_OF_LIST markers off descriptions;
given that the current check is only for ->name being NULL, sometimes
we get unlucky and the code apparently works and no one spots the error.

Explicitly add a flag, VMS_END that should be set, and assert it is
set during the traversal.

Note: This can't go in until we update the copy of vmstate.h in slirp.

Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2023-02-06 19:22:56 +01:00
Daniel P. Berrangé
fbfa6404e5 migration: rename qemu_ftell to qemu_file_total_transferred
The name 'ftell' gives the misleading impression that the QEMUFile
objects are seekable. This is not the case, as in general we just
have an opaque stream. The users of this method are only interested
in the total bytes processed. This switches to a new name that
reflects the intended usage.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
   dgilbert: Wrapped long line
2022-06-22 19:33:36 +01:00
Peter Maydell
1862198702 migration: Remove load_state_old and minimum_version_id_old
There are no longer any VMStateDescription structs in the tree which
use the load_state_old support for custom handling of incoming
migration from very old QEMU.  Remove the mechanism entirely.

This includes removing one stray useless setting of
minimum_version_id_old in a VMStateDescription with no load_state_old
function, which crept in after the global weeding-out of them in
commit 17e3134061.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20220215175705.3846411-1-peter.maydell@linaro.org>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Francisco Iglesias <francisco.iglesias@xilinx.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-03-02 18:20:45 +00:00
Markus Armbruster
3ddba9a9e9 migration: Replace migration's JSON writer by the general one
Commit 8118f0950f "migration: Append JSON description of migration
stream" needs a JSON writer.  The existing qobject_to_json() wasn't a
good fit, because it requires building a QObject to convert.  Instead,
migration got its very own JSON writer, in commit 190c882ce2 "QJSON:
Add JSON writer".  It tacitly limits numbers to int64_t, and strings
contents to characters that don't need escaping, unlike
qobject_to_json().

The previous commit factored the JSON writer out of qobject_to_json().
Replace migration's JSON writer by it.

Cc: Juan Quintela <quintela@redhat.com>
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20201211171152.146877-17-armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-12-19 10:39:16 +01:00
Bihong Yu
395cb45009 migration: Add spaces around operator
Signed-off-by: Bihong Yu <yubihong@huawei.com>
Reviewed-by: Chuan Zheng <zhengchuan@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <1603163448-27122-4-git-send-email-yubihong@huawei.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-10-26 16:15:04 +00:00
Chen Qun
600fe89d6e migration/vmstate: Remove redundant statement in vmstate_save_state_v()
The "ret" has been assigned in all branches. It didn't need to be
 assigned separately.

Clang static code analyzer show warning:
  migration/vmstate.c:365:17: warning: Value stored to 'ret' is never read
                ret = 0;
                ^     ~

Reported-by: Euler Robot <euler.robot@huawei.com>
Signed-off-by: Chen Qun <kuhn.chenqun@huawei.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2020-02-28 09:25:49 +01:00
Markus Armbruster
a8d2532645 Include qemu-common.h exactly where needed
No header includes qemu-common.h after this commit, as prescribed by
qemu-common.h's file comment.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190523143508.25387-5-armbru@redhat.com>
[Rebased with conflicts resolved automatically, except for
include/hw/arm/xlnx-zynqmp.h hw/arm/nrf51_soc.c hw/arm/msf2-soc.c
block/qcow2-refcount.c block/qcow2-cluster.c block/qcow2-cache.c
target/arm/cpu.h target/lm32/cpu.h target/m68k/cpu.h target/mips/cpu.h
target/moxie/cpu.h target/nios2/cpu.h target/openrisc/cpu.h
target/riscv/cpu.h target/tilegx/cpu.h target/tricore/cpu.h
target/unicore32/cpu.h target/xtensa/cpu.h; bsd-user/main.c and
net/tap-bsd.c fixed up]
2019-06-12 13:20:20 +02:00
Wei Yang
f2dd7eddf2 vmstate: check subsection_found is enough
subsection_found is true implies vmdesc is not NULL.

This patch remove the additional check on vmdesc and rename
subsection_found to vmdesc_has_subsections to make it more self-explain.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>

Message-Id: <20190403011016.12549-1-richardw.yang@linux.intel.com>
Acked-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-05-14 17:33:35 +01:00
Aaron Lindsay
8c07559fc7 migration: Add post_save function to VMStateDescription
In some cases it may be helpful to modify state before saving it for
migration, and then modify the state back after it has been saved. The
existing pre_save function provides half of this functionality. This
patch adds a post_save function to provide the second half.

Signed-off-by: Aaron Lindsay <aclindsa@gmail.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-id: 20181211151945.29137-2-aaron@os.amperecomputing.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2019-01-21 10:38:55 +00:00
Marc-André Lureau
03fee66fde vmstate: constify VMStateField
Because they are supposed to remain const.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20181114132931.22624-1-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-11-27 15:35:15 +01:00
Peter Maydell
6f4923fcad migration: Correctly handle subsections with no 'needed' function
Currently the vmstate subsection handling code treats a subsection
with no 'needed' function pointer as if it were the subsection
list terminator, so the subsection is never transferred and nor
is any subsection following it in the list.

Handle NULL 'needed' function pointers in subsections in the same
way that we do for top level VMStateDescription structures:
treat the subsection as always being needed.

This doesn't change behaviour for the current set of devices
in the tree, because all subsections declare a 'needed' function.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-08-22 11:40:47 +02:00
Peter Maydell
f67c9b693a acpi, vhost, misc: fixes, features
vDPA support, fix to vhost blk RO bit handling, some include path
 cleanups, NFIT ACPI table.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

acpi, vhost, misc: fixes, features

vDPA support, fix to vhost blk RO bit handling, some include path
cleanups, NFIT ACPI table.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Fri 01 Jun 2018 17:25:19 BST
# gpg:                using RSA key 281F0DB8D28D5469
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>"
# gpg:                 aka "Michael S. Tsirkin <mst@redhat.com>"
# Primary key fingerprint: 0270 606B 6F3C DF3D 0B17  0970 C350 3912 AFBE 8E67
#      Subkey fingerprint: 5D09 FD08 71C8 F85B 94CA  8A0D 281F 0DB8 D28D 5469

* remotes/mst/tags/for_upstream: (31 commits)
  vhost-blk: turn on pre-defined RO feature bit
  ACPI testing: test NFIT platform capabilities
  nvdimm, acpi: support NFIT platform capabilities
  tests/.gitignore: add entry for generated file
  arch_init: sort architectures
  ui: use local path for local headers
  qga: use local path for local headers
  colo: use local path for local headers
  migration: use local path for local headers
  usb: use local path for local headers
  sd: fix up include
  vhost-scsi: drop an unused include
  ppc: use local path for local headers
  rocker: drop an unused include
  e1000e: use local path for local headers
  ioapic: fix up includes
  ide: use local path for local headers
  display: use local path for local headers
  trace: use local path for local headers
  migration: drop an unused include
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-06-04 10:15:16 +01:00
Michael S. Tsirkin
53d37d36ca migration: use local path for local headers
When pulling in headers that are in the same directory as the C file (as
opposed to one in include/), we should use its relative path, without a
directory.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
2018-06-01 19:20:38 +03:00
Corey Minyard
2dc6660bd8 vmstate: Add a VSTRUCT type
The VMS_STRUCT has no way to specify which version of a structure
to use.  Add a type and a new field to allow the specific version
of a structure to be used.

Signed-off-by: Corey Minyard <cminyard@mvista.com>
Message-Id: <1524670052-28373-2-git-send-email-minyard@acm.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-06-01 15:13:46 +02:00
Dr. David Alan Gilbert
f3cadd39c4 migration: wire vmstate_save_state errors up to vmstate_subsection_save
Route the errors from vmstate_save_state up through
vmstate_subsection_save (and back down, all rather recursive).

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20170925112917.21340-5-dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  Commit message fixed up as per Peter's review
2017-09-27 11:38:21 +01:00
Dr. David Alan Gilbert
88b0faf185 migration: Check field save returns
Check the return values from vmstate_save_state for fields and also the
return values from 'put' for fields that use that.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20170925112917.21340-4-dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-09-27 11:37:11 +01:00
Dr. David Alan Gilbert
551dbd0846 migration: check pre_save return in vmstate_save_state
Check the return value of pre_save state and fail vmstate_save_state
if the pre_save failed.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20170925112917.21340-3-dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-09-27 11:36:31 +01:00
Juan Quintela
6666c96aac migration: Move migration.h to migration/
Nothing uses it outside of migration.h

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
2017-06-13 11:00:45 +02:00
Juan Quintela
c3d2e2e76c migration: Move constants to savevm.h
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
2017-06-13 11:00:45 +02:00
Juan Quintela
08a0aee15c migration: Split qemu-file.h
Split the file into public and internal interfaces.  I have to rename
the external one because we can't have two include files with the same
name in the same directory.  Build system gets confused.  The only
exported functions are the ones that handle basic types.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-06-01 18:49:22 +02:00
Juan Quintela
576d1abc20 migration: Split vmstate-types.c from vmstate.c
Now one just has the interperter, and the other has the basic types.
Once there, add copyright boilerplate.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>

--

Use GPL v2 or later.  Detected by David.
2017-05-18 19:20:59 +02:00
Juan Quintela
05b98c22f8 migration: Move qjson.h to migration/
It is only used for migration code.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-05-18 19:20:59 +02:00
QingFeng Hao
e1e686c1fa vmstate: fix failed iotests case 68 and 91
This problem affects s390x only if we are running without KVM.
Basically, S390CPU.irqstate is unused if we do not use KVM,
and thus no buffer is allocated.
This causes size=0, first_elem=NULL and n_elems=1 in
vmstate_load_state and vmstate_save_state. And the assert fails.
With this fix we can go back to the old behavior and support
VMS_VBUFFER with size 0 and nullptr.

Signed-off-by: QingFeng Hao <haoqf@linux.vnet.ibm.com>
Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2017-03-16 08:59:52 +01:00
Halil Pasic
07d4e69147 migration/vmstate: fix array of ptr with nullptrs
Make VMS_ARRAY_OF_POINTER cope with null pointers. Previously the
reward for trying to migrate an array with some null pointers in it was
an illegal memory access, that is a swift and painless death of the
process.  Let's make vmstate cope with this scenario.

The general approach is, when we encounter a null pointer (element),
instead of following the pointer to save/load the data behind it, we
save/load a placeholder. This way we can detect if we expected a null
pointer at the load side but not null data was saved instead.

Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Guenther Hutzl <hutzl@linux.vnet.ibm.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20170222160119.52771-4-pasic@linux.vnet.ibm.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-02-28 11:29:00 +00:00
Halil Pasic
cbfda0e6cf migration/vmstate: split up vmstate_base_addr
Currently vmstate_base_addr does several things: it pinpoints the field
within the struct, possibly allocates memory and possibly does the first
pointer dereference. Obviously allocation is needed only for load.

Let us split up the functionality in vmstate_base_addr and move the
address manipulations (that is everything but the allocation logic) to
load and save so it becomes more obvious what is actually going on. Like
this all the address calculations (and the handling of the flags
controlling these) is in one place and the sequence is more obvious.

The newly introduced function vmstate_handle_alloc also fixes the
allocation for the unused VMS_VBUFFER|VMS_MULTIPLY|VMS_ALLOC scenario
and is substantially simpler than the original vmstate_base_addr.

In load and save some asserts are added so it's easier to debug
situations where we would end up with a null pointer dereference.

Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20170222160119.52771-3-pasic@linux.vnet.ibm.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-02-28 11:29:00 +00:00
Halil Pasic
e84641f73d migration/vmstate: renames in (load|save)_state
The vmstate_(load|save)_state start out with an a void *opaque pointing
to some struct, and manipulate one or more elements of one field within
that struct.

First the field within the struct is pinpointed as opaque + offset, then
if this is a pointer the pointer is dereferenced to obtain a pointer to
the first element of the vmstate field. Pointers to further elements if
any are calculated as first_element + i * element_size (where i is the
zero based index of the element in question).

Currently base_addr and addr is used as a variable name for the pointer
to the first element and the pointer to the current element being
processed. This is suboptimal because base_addr is somewhat
counter-intuitive (because obtained as base + offset) and both base_addr
and addr not very descriptive (that we have a pointer should be clear
from the fact that it is declared as a pointer).

Let make things easier to understand by renaming base_addr to first_elem
and addr to curr_elem. This has the additional benefit of harmonizing
with other names within the scope (n_elems, vmstate_n_elems).

Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20170222160119.52771-2-pasic@linux.vnet.ibm.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-02-28 11:29:00 +00:00
Dr. David Alan Gilbert
bcf4513129 migration: Add VMSTATE_WITH_TMP
VMSTATE_WITH_TMP is for handling structures where some calculation
or rearrangement of the data needs to be performed before the data
hits the wire.
For example,  where the value on the wire is an offset from a
non-migrated base, but the data in the structure is the actual pointer.

To use it, a temporary type is created and a vmsd used on that type.
The first element of the type must be 'parent' a pointer back to the
type of the main structure.  VMSTATE_WITH_TMP takes care of allocating
and freeing the temporary before running the child vmsd.

The post_load/pre_save on the child vmsd can copy things from the parent
to the temporary using the parent pointer and do any other calculations
needed; it can then use normal VMSD entries to do the actual data
storage without having to fiddle around with qemu_get_*/qemu_put_*

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20170203160651.19917-3-dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-02-13 17:27:14 +00:00
Halil Pasic
59046ec29a migration: consolidate VMStateField.start
The member VMStateField.start is used for two things, partial data
migration for VBUFFER data (basically provide migration for a
sub-buffer) and for locating next in QTAILQ.

The implementation of the VBUFFER feature is broken when VMSTATE_ALLOC
is used. This however goes unnoticed because actually partial migration
for VBUFFER is not used at all.

Let's consolidate the usage of VMStateField.start by removing support
for partial migration for VBUFFER.

Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com>

Message-Id: <20170203175217.45562-1-pasic@linux.vnet.ibm.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-02-13 17:27:13 +00:00
Dr. David Alan Gilbert
46a02a7451 migration/tracing: Add tracing on save
Add some tracing to vmstate_subsection_save and vmstate_save_state
to help in debugging when you're not sure if a conditional piece
of data is being saved.

In vmstate_subsection_save I renamed the inner vmsd to avoid the aliasing
and be able to print both names.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20161212125838.14425-1-dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-01-24 18:00:32 +00:00
Jianjun Duan
cde7ee5974 migration: add error_report
Added error_report where version_ids do not match in vmstate_load_state.

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

Signed-off-by: Jianjun Duan <duanj@linux.vnet.ibm.com>
Message-Id: <1484852453-12728-5-git-send-email-duanj@linux.vnet.ibm.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-01-24 17:54:47 +00:00
Jianjun Duan
94869d5c52 migration: migrate QTAILQ
Currently we cannot directly transfer a QTAILQ instance because of the
limitation in the migration code. Here we introduce an approach to
transfer such structures. We created VMStateInfo vmstate_info_qtailq
for QTAILQ. Similar VMStateInfo can be created for other data structures
such as list.

When a QTAILQ is migrated from source to target, it is appended to the
corresponding QTAILQ structure, which is assumed to have been properly
initialized.

This approach will be used to transfer pending_events and ccs_list in spapr
state.

We also create some macros in qemu/queue.h to access a QTAILQ using pointer
arithmetic. This ensures that we do not depend on the implementation
details about QTAILQ in the migration code.

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

Signed-off-by: Jianjun Duan <duanj@linux.vnet.ibm.com>
Message-Id: <1484852453-12728-3-git-send-email-duanj@linux.vnet.ibm.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-01-24 17:54:47 +00:00
Jianjun Duan
2c21ee769e migration: extend VMStateInfo
Current migration code cannot handle some data structures such as
QTAILQ in qemu/queue.h. Here we extend the signatures of put/get
in VMStateInfo so that customized handling is supported. put now
will return int type.

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

Signed-off-by: Jianjun Duan <duanj@linux.vnet.ibm.com>
Message-Id: <1484852453-12728-2-git-send-email-duanj@linux.vnet.ibm.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-01-24 17:54:47 +00:00
Dr. David Alan Gilbert
49228e17ed migration: Report values for comparisons
Report the values when a comparison fails; together with
the previous patch that prints the device and field names
this should give a good idea of why loading the migration failed.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2016-10-13 17:22:38 +02:00
Dr. David Alan Gilbert
a1771070e7 migration: report an error giving the failed field
When a field fails to load (typically due to a limit
check, or a call to a get/put) report the device and field
to give an indication of the cause.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2016-10-13 17:22:38 +02:00
Dr. David Alan Gilbert
023ad1a6e9 migration: Trace improvements
A couple of improvements to tracing that have come out of helping
people with migration problems:
  * vmstate_n_elems trace the count/name - for when you have problems
    getting array counts right
  * vmstate_subsection_load_bad - add the idstr, for when you receive a
    subsection you weren't expecting.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <1465896986-16132-1-git-send-email-dgilbert@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-06-17 18:23:53 +05:30
Markus Armbruster
17b74b9867 migration: Move qjson.[ch] to migration/
Type QJSON lets you build JSON text.  Its interface mirrors (a subset
of) abstract JSON syntax.

QAPI output visitors also produce JSON text.  They assert their
preconditions and invariants, and therefore abort on incorrect use.

Contrastingly, QJSON does *not* detect incorrect use.  It happily
produces invalid JSON then.  This is what migration wants.

QJSON was designed for migration, and migration is its only user.
Move it to migration/ for proper coverage by MAINTAINERS, and to deter
accidental use outside migration.

[Pointed out by Eric: QJSON was added in commits 0457d07..b174257
 -- Amit]

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <1462380558-2030-2-git-send-email-armbru@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-23 14:16:09 +05:30
Peter Maydell
1393a48526 migration: Clean up includes
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1453832250-766-2-git-send-email-peter.maydell@linaro.org
2016-01-29 15:07:22 +00:00