| Message ID | 1332157685-31701-2-git-send-email-stefano.stabellini@eu.citrix.com |
|---|---|
| State | New |
| Headers | show |
On Mon, 19 Mar 2012 11:48:01 +0000 Stefano Stabellini <stefano.stabellini@eu.citrix.com> wrote: > - add an "is_ram" flag to SaveStateEntry; > > - register_savevm_live sets is_ram for live_savevm devices; > > - introduce a "xen-save-devices-state" QAPI command that can be used to save > the state of all devices, but not the RAM or the block devices of the > VM. Is this series expected to go in through the QMP queue?
On Mon, 19 Mar 2012, Luiz Capitulino wrote: > > - add an "is_ram" flag to SaveStateEntry; > > > > - register_savevm_live sets is_ram for live_savevm devices; > > > > - introduce a "xen-save-devices-state" QAPI command that can be used to save > > the state of all devices, but not the RAM or the block devices of the > > VM. > > Is this series expected to go in through the QMP queue? That would be OK. Otherwise I was going to submit a pull request to Anthony as soon as you ack the second patch.
On 03/19/2012 10:16 AM, Stefano Stabellini wrote: > On Mon, 19 Mar 2012, Luiz Capitulino wrote: >>> - add an "is_ram" flag to SaveStateEntry; >>> >>> - register_savevm_live sets is_ram for live_savevm devices; >>> >>> - introduce a "xen-save-devices-state" QAPI command that can be used to save >>> the state of all devices, but not the RAM or the block devices of the >>> VM. >> >> Is this series expected to go in through the QMP queue? > > That would be OK. Otherwise I was going to submit a pull request to > Anthony as soon as you ack the second patch. I'd prefer Stefano do a pull request. I'm happy with the level of reviews to merge this. Regards, Anthony Liguori
On Mon, 19 Mar 2012 11:48:01 +0000 Stefano Stabellini <stefano.stabellini@eu.citrix.com> wrote: > - add an "is_ram" flag to SaveStateEntry; > > - register_savevm_live sets is_ram for live_savevm devices; > > - introduce a "xen-save-devices-state" QAPI command that can be used to save > the state of all devices, but not the RAM or the block devices of the > VM. > > Changes in v8: > > - rename save-devices-state to xen-save-devices-state. > > Changes in v7: > > - rename save_devices to save-devices-state. > > Changes in v6: > > - remove the is_ram parameter from register_savevm_live and sets is_ram > if the device is a live_savevm device; > > - introduce save_devices as a QAPI command, write a better description > for it; > > - fix CODING_STYLE; > > - introduce a new doc to explain the save format used by save_devices. > > Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> > Reviewed-by: Anthony Liguori <aliguori@us.ibm.com> Acked-by: Luiz Capitulino <lcapitulino@redhat.com> > --- > docs/xen-save-devices-state.txt | 34 ++++++++++++++++++ > qapi-schema.json | 19 ++++++++++ > qmp-commands.hx | 27 +++++++++++++++ > savevm.c | 71 +++++++++++++++++++++++++++++++++++++++ > 4 files changed, 151 insertions(+), 0 deletions(-) > create mode 100644 docs/xen-save-devices-state.txt > > diff --git a/docs/xen-save-devices-state.txt b/docs/xen-save-devices-state.txt > new file mode 100644 > index 0000000..92e08db > --- /dev/null > +++ b/docs/xen-save-devices-state.txt > @@ -0,0 +1,34 @@ > += Save Devices = > + > +QEMU has code to load/save the state of the guest that it is running. > +These are two complementary operations. Saving the state just does > +that, saves the state for each device that the guest is running. > + > +These operations are normally used with migration (see migration.txt), > +however it is also possible to save the state of all devices to file, > +without saving the RAM or the block devices of the VM. > + > +This operation is called "xen-save-devices-state" (see > +QMP/qmp-commands.txt) > + > + > +The binary format used in the file is the following: > + > + > +------------------------------------------- > + > +32 bit big endian: QEMU_VM_FILE_MAGIC > +32 bit big endian: QEMU_VM_FILE_VERSION > + > +for_each_device > +{ > + 8 bit: QEMU_VM_SECTION_FULL > + 32 bit big endian: section_id > + 8 bit: idstr (ID string) length > + string: idstr (ID string) > + 32 bit big endian: instance_id > + 32 bit big endian: version_id > + buffer: device specific data > +} > + > +8 bit: QEMU_VM_EOF > diff --git a/qapi-schema.json b/qapi-schema.json > index d0b6792..def69a9 100644 > --- a/qapi-schema.json > +++ b/qapi-schema.json > @@ -1593,3 +1593,22 @@ > { 'command': 'qom-list-types', > 'data': { '*implements': 'str', '*abstract': 'bool' }, > 'returns': [ 'ObjectTypeInfo' ] } > + > +## > +# @xen-save-devices-state: > +# > +# Save the state of all devices to file. The RAM and the block devices > +# of the VM are not saved by this command. > +# > +# @filename: the file to save the state of the devices to as binary > +# data. See xen-save-devices-state.txt for a description of the binary > +# format. > +# > +# Returns: Nothing on success > +# If @filename cannot be opened, OpenFileFailed > +# If an I/O error occurs while writing the file, IOError > +# > +# Since: 1.1 > +## > +{ 'command': 'xen-save-devices-state', 'data': {'filename': 'str'} } > + > diff --git a/qmp-commands.hx b/qmp-commands.hx > index 705f704..dbb6236 100644 > --- a/qmp-commands.hx > +++ b/qmp-commands.hx > @@ -444,6 +444,33 @@ Note: inject-nmi is only supported for x86 guest currently, it will > EQMP > > { > + .name = "xen-save-devices-state", > + .args_type = "filename:F", > + .mhandler.cmd_new = qmp_marshal_input_xen_save_devices_state, > + }, > + > +SQMP > +xen-save-devices-state > +------- > + > +Save the state of all devices to file. The RAM and the block devices > +of the VM are not saved by this command. > + > +Arguments: > + > +- "filename": the file to save the state of the devices to as binary > +data. See xen-save-devices-state.txt for a description of the binary > +format. > + > +Example: > + > +-> { "execute": "xen-save-devices-state", > + "arguments": { "filename": "/tmp/save" } } > +<- { "return": {} } > + > +EQMP > + > + { > .name = "migrate", > .args_type = "detach:-d,blk:-b,inc:-i,uri:s", > .params = "[-d] [-b] [-i] uri", > diff --git a/savevm.c b/savevm.c > index 80be1ff..0e61eb0 100644 > --- a/savevm.c > +++ b/savevm.c > @@ -84,6 +84,7 @@ > #include "qemu-timer.h" > #include "cpus.h" > #include "memory.h" > +#include "qmp-commands.h" > > #define SELF_ANNOUNCE_ROUNDS 5 > > @@ -1177,6 +1178,7 @@ typedef struct SaveStateEntry { > void *opaque; > CompatEntry *compat; > int no_migrate; > + int is_ram; > } SaveStateEntry; > > > @@ -1241,6 +1243,10 @@ int register_savevm_live(DeviceState *dev, > se->opaque = opaque; > se->vmsd = NULL; > se->no_migrate = 0; > + /* if this is a live_savem then set is_ram */ > + if (save_live_state != NULL) { > + se->is_ram = 1; > + } > > if (dev && dev->parent_bus && dev->parent_bus->info->get_dev_path) { > char *id = dev->parent_bus->info->get_dev_path(dev); > @@ -1728,6 +1734,45 @@ out: > return ret; > } > > +static int qemu_save_device_state(QEMUFile *f) > +{ > + SaveStateEntry *se; > + > + qemu_put_be32(f, QEMU_VM_FILE_MAGIC); > + qemu_put_be32(f, QEMU_VM_FILE_VERSION); > + > + cpu_synchronize_all_states(); > + > + QTAILQ_FOREACH(se, &savevm_handlers, entry) { > + int len; > + > + if (se->is_ram) { > + continue; > + } > + if (se->save_state == NULL && se->vmsd == NULL) { > + continue; > + } > + > + /* Section type */ > + qemu_put_byte(f, QEMU_VM_SECTION_FULL); > + qemu_put_be32(f, se->section_id); > + > + /* ID string */ > + len = strlen(se->idstr); > + qemu_put_byte(f, len); > + qemu_put_buffer(f, (uint8_t *)se->idstr, len); > + > + qemu_put_be32(f, se->instance_id); > + qemu_put_be32(f, se->version_id); > + > + vmstate_save(f, se); > + } > + > + qemu_put_byte(f, QEMU_VM_EOF); > + > + return qemu_file_get_error(f); > +} > + > static SaveStateEntry *find_se(const char *idstr, int instance_id) > { > SaveStateEntry *se; > @@ -2109,6 +2154,32 @@ void do_savevm(Monitor *mon, const QDict *qdict) > vm_start(); > } > > +void qmp_xen_save_devices_state(const char *filename, Error **errp) > +{ > + QEMUFile *f; > + int saved_vm_running; > + int ret; > + > + saved_vm_running = runstate_is_running(); > + vm_stop(RUN_STATE_SAVE_VM); > + > + f = qemu_fopen(filename, "wb"); > + if (!f) { > + error_set(errp, QERR_OPEN_FILE_FAILED, filename); > + goto the_end; > + } > + ret = qemu_save_device_state(f); > + qemu_fclose(f); > + if (ret < 0) { > + error_set(errp, QERR_IO_ERROR); > + } > + > + the_end: > + if (saved_vm_running) > + vm_start(); > + return; > +} > + > int load_vmstate(const char *name) > { > BlockDriverState *bs, *bs_vm_state;
On Mon, 19 Mar 2012, Luiz Capitulino wrote: > On Mon, 19 Mar 2012 11:48:01 +0000 > Stefano Stabellini <stefano.stabellini@eu.citrix.com> wrote: > > > - add an "is_ram" flag to SaveStateEntry; > > > > - register_savevm_live sets is_ram for live_savevm devices; > > > > - introduce a "xen-save-devices-state" QAPI command that can be used to save > > the state of all devices, but not the RAM or the block devices of the > > VM. > > > > Changes in v8: > > > > - rename save-devices-state to xen-save-devices-state. > > > > Changes in v7: > > > > - rename save_devices to save-devices-state. > > > > Changes in v6: > > > > - remove the is_ram parameter from register_savevm_live and sets is_ram > > if the device is a live_savevm device; > > > > - introduce save_devices as a QAPI command, write a better description > > for it; > > > > - fix CODING_STYLE; > > > > - introduce a new doc to explain the save format used by save_devices. > > > > Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> > > Reviewed-by: Anthony Liguori <aliguori@us.ibm.com> > > Acked-by: Luiz Capitulino <lcapitulino@redhat.com> Thanks!
On Mon, 19 Mar 2012, Anthony Liguori wrote: > On 03/19/2012 10:16 AM, Stefano Stabellini wrote: > > On Mon, 19 Mar 2012, Luiz Capitulino wrote: > >>> - add an "is_ram" flag to SaveStateEntry; > >>> > >>> - register_savevm_live sets is_ram for live_savevm devices; > >>> > >>> - introduce a "xen-save-devices-state" QAPI command that can be used to save > >>> the state of all devices, but not the RAM or the block devices of the > >>> VM. > >> > >> Is this series expected to go in through the QMP queue? > > > > That would be OK. Otherwise I was going to submit a pull request to > > Anthony as soon as you ack the second patch. > > I'd prefer Stefano do a pull request. > > I'm happy with the level of reviews to merge this. Done
diff --git a/docs/xen-save-devices-state.txt b/docs/xen-save-devices-state.txt new file mode 100644 index 0000000..92e08db --- /dev/null +++ b/docs/xen-save-devices-state.txt @@ -0,0 +1,34 @@ += Save Devices = + +QEMU has code to load/save the state of the guest that it is running. +These are two complementary operations. Saving the state just does +that, saves the state for each device that the guest is running. + +These operations are normally used with migration (see migration.txt), +however it is also possible to save the state of all devices to file, +without saving the RAM or the block devices of the VM. + +This operation is called "xen-save-devices-state" (see +QMP/qmp-commands.txt) + + +The binary format used in the file is the following: + + +------------------------------------------- + +32 bit big endian: QEMU_VM_FILE_MAGIC +32 bit big endian: QEMU_VM_FILE_VERSION + +for_each_device +{ + 8 bit: QEMU_VM_SECTION_FULL + 32 bit big endian: section_id + 8 bit: idstr (ID string) length + string: idstr (ID string) + 32 bit big endian: instance_id + 32 bit big endian: version_id + buffer: device specific data +} + +8 bit: QEMU_VM_EOF diff --git a/qapi-schema.json b/qapi-schema.json index d0b6792..def69a9 100644 --- a/qapi-schema.json +++ b/qapi-schema.json @@ -1593,3 +1593,22 @@ { 'command': 'qom-list-types', 'data': { '*implements': 'str', '*abstract': 'bool' }, 'returns': [ 'ObjectTypeInfo' ] } + +## +# @xen-save-devices-state: +# +# Save the state of all devices to file. The RAM and the block devices +# of the VM are not saved by this command. +# +# @filename: the file to save the state of the devices to as binary +# data. See xen-save-devices-state.txt for a description of the binary +# format. +# +# Returns: Nothing on success +# If @filename cannot be opened, OpenFileFailed +# If an I/O error occurs while writing the file, IOError +# +# Since: 1.1 +## +{ 'command': 'xen-save-devices-state', 'data': {'filename': 'str'} } + diff --git a/qmp-commands.hx b/qmp-commands.hx index 705f704..dbb6236 100644 --- a/qmp-commands.hx +++ b/qmp-commands.hx @@ -444,6 +444,33 @@ Note: inject-nmi is only supported for x86 guest currently, it will EQMP { + .name = "xen-save-devices-state", + .args_type = "filename:F", + .mhandler.cmd_new = qmp_marshal_input_xen_save_devices_state, + }, + +SQMP +xen-save-devices-state +------- + +Save the state of all devices to file. The RAM and the block devices +of the VM are not saved by this command. + +Arguments: + +- "filename": the file to save the state of the devices to as binary +data. See xen-save-devices-state.txt for a description of the binary +format. + +Example: + +-> { "execute": "xen-save-devices-state", + "arguments": { "filename": "/tmp/save" } } +<- { "return": {} } + +EQMP + + { .name = "migrate", .args_type = "detach:-d,blk:-b,inc:-i,uri:s", .params = "[-d] [-b] [-i] uri", diff --git a/savevm.c b/savevm.c index 80be1ff..0e61eb0 100644 --- a/savevm.c +++ b/savevm.c @@ -84,6 +84,7 @@ #include "qemu-timer.h" #include "cpus.h" #include "memory.h" +#include "qmp-commands.h" #define SELF_ANNOUNCE_ROUNDS 5 @@ -1177,6 +1178,7 @@ typedef struct SaveStateEntry { void *opaque; CompatEntry *compat; int no_migrate; + int is_ram; } SaveStateEntry; @@ -1241,6 +1243,10 @@ int register_savevm_live(DeviceState *dev, se->opaque = opaque; se->vmsd = NULL; se->no_migrate = 0; + /* if this is a live_savem then set is_ram */ + if (save_live_state != NULL) { + se->is_ram = 1; + } if (dev && dev->parent_bus && dev->parent_bus->info->get_dev_path) { char *id = dev->parent_bus->info->get_dev_path(dev); @@ -1728,6 +1734,45 @@ out: return ret; } +static int qemu_save_device_state(QEMUFile *f) +{ + SaveStateEntry *se; + + qemu_put_be32(f, QEMU_VM_FILE_MAGIC); + qemu_put_be32(f, QEMU_VM_FILE_VERSION); + + cpu_synchronize_all_states(); + + QTAILQ_FOREACH(se, &savevm_handlers, entry) { + int len; + + if (se->is_ram) { + continue; + } + if (se->save_state == NULL && se->vmsd == NULL) { + continue; + } + + /* Section type */ + qemu_put_byte(f, QEMU_VM_SECTION_FULL); + qemu_put_be32(f, se->section_id); + + /* ID string */ + len = strlen(se->idstr); + qemu_put_byte(f, len); + qemu_put_buffer(f, (uint8_t *)se->idstr, len); + + qemu_put_be32(f, se->instance_id); + qemu_put_be32(f, se->version_id); + + vmstate_save(f, se); + } + + qemu_put_byte(f, QEMU_VM_EOF); + + return qemu_file_get_error(f); +} + static SaveStateEntry *find_se(const char *idstr, int instance_id) { SaveStateEntry *se; @@ -2109,6 +2154,32 @@ void do_savevm(Monitor *mon, const QDict *qdict) vm_start(); } +void qmp_xen_save_devices_state(const char *filename, Error **errp) +{ + QEMUFile *f; + int saved_vm_running; + int ret; + + saved_vm_running = runstate_is_running(); + vm_stop(RUN_STATE_SAVE_VM); + + f = qemu_fopen(filename, "wb"); + if (!f) { + error_set(errp, QERR_OPEN_FILE_FAILED, filename); + goto the_end; + } + ret = qemu_save_device_state(f); + qemu_fclose(f); + if (ret < 0) { + error_set(errp, QERR_IO_ERROR); + } + + the_end: + if (saved_vm_running) + vm_start(); + return; +} + int load_vmstate(const char *name) { BlockDriverState *bs, *bs_vm_state;