Currently libvirt doesn't confirm whether the guest has responded to the
disk removal request. In some cases this can leave the guest with
continued access to the device while the mgmt layer believes that it has
been removed. With a recent qemu monitor command[1] we can
deterministically revoke a guests access to the disk (on the QEMU side)
to ensure no futher access is permitted.
This patch adds support for the drive_unplug() command and introduces it
in the disk removal paths. There is some discussion to be had about how
to handle the case where the guest is running in a QEMU without this
command (and the fact that we currently don't have a way of detecting
what monitor commands are available).
Changes since v2:
- use VIR_ERROR to report when unplug command not found
Changes since v1:
- return > 0 when command isn't present, < 0 on command failure
- detect when drive_unplug command isn't present and log error
instead of failing entire command
Signed-off-by: Ryan Harper <ryanh@us.ibm.com>
QEMU allows forcing a CDROM eject even if the guest has locked the device.
Expose this via a new UpdateDevice flag, VIR_DOMAIN_DEVICE_MODIFY_FORCE.
This has been requested for RHEV:
https://bugzilla.redhat.com/show_bug.cgi?id=626305
v2: Change flag name, bool cleanups
A couple of places in the text monitor were overwriting the
'ret' variable with a >= 0 value before success was actually
determined. So later error paths would not correctly return
the -1 value. The drive_add code was not checking for errors
like missing command
* src/qemu/qemu_monitor_text.c: Misc error handling fixes
Older dash mistakenly truncates regular files when using <> redirection;
this kills our use of double dd to reduce storage overhead when
saving qemu images. But qemu insists on running a command through
/bin/sh, so we work around it by having qemu run $sh -c 'real command'
when we have a replacement $sh in mind.
* configure.ac (VIR_WRAPPER_SHELL): Define to a replacement shell,
if /bin/sh is broken on <> redirection.
* src/qemu/qemu_monitor.h (VIR_WRAPPER_SHELL_PREFIX)
(VIR_WRAPPER_SHELL_SUFFIX): New macros.
* src/qemu/qemu_monitor_text.c (qemuMonitorTextMigrateToFile): Use
them.
* src/qemu/qemu_monitor_json.c (qemuMonitorJSONMigrateToFile):
Likewise.
Implement the qemu driver's virDomainQemuMonitorCommand
and hook it into the API entry point.
Changes since v1:
- Rename the (external) qemuMonitorCommand to qemuDomainMonitorCommand
- Add virCheckFlags to qemuDomainMonitorCommand
Changes since v2:
- Drop ATTRIBUTE_UNUSED from the flags
Changes since v3:
- Add a flag to priv so we only print out monitor command warning once. Note
that this has not been plumbed into qemuDomainObjPrivateXMLFormat or
qemuDomainObjPrivateXMLParse, which means that if you run a monitor command,
restart libvirtd, and then run another monitor command, you may get an
an erroneous VIR_INFO. It's a pretty minor matter, and I didn't think it
warranted the additional code.
- Add BeginJob/EndJob calls around EnterMonitor/ExitMonitor
Signed-off-by: Chris Lalancette <clalance@redhat.com>
The patches for shared storage migration were not correctly written
for json mode. Thus the 'blk' and 'inc' parameters were never being
set. In addition they didn't set the QEMU_MONITOR_MIGRATE_BACKGROUND
so migration was synchronous. Due to multiple bugs in QEMU's JSON
impl this wasn't noticed because it treated the sync migration requst
as asynchronous anyway. Finally 'background' parameter was converted
to take arbitrary flags but not renamed, and not all uses were changed
to unsigned int.
* src/qemu/qemu_driver.c: Set QEMU_MONITOR_MIGRATE_BACKGROUND in
doNativeMigrate
* src/qemu/qemu_monitor_json.c: Process QEMU_MONITOR_MIGRATE_NON_SHARED_DISK
and QEMU_MONITOR_MIGRATE_NON_SHARED_INC flags
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.h, src/qemu/qemu_monitor_text.c,
src/qemu/qemu_monitor_text.h: change 'int background' to
'unsigned int flags' in migration APIs. Add logging of flags
parameter
Followup to https://bugzilla.redhat.com/show_bug.cgi?id=599091,
commit 20206a4b, to reduce disk waste in padding.
* src/qemu/qemu_monitor.h (QEMU_MONITOR_MIGRATE_TO_FILE_BS): Drop
back to 4k.
(QEMU_MONITOR_MIGRATE_TO_FILE_TRANSFER_SIZE): New macro.
* src/qemu/qemu_driver.c (qemudDomainSaveFlag): Update comment.
* src/qemu/qemu_monitor_text.c (qemuMonitorTextMigrateToFile): Use
two invocations of dd to output non-aligned large blocks.
* src/qemu/qemu_monitor_json.c (qemuMonitorJSONMigrateToFile):
Likewise.
Any output at all from device_add indicates an error in the
command execution. Thus it needs to check for reply != ""
* src/qemu/qemu_monitor_text.c: Fix reply check for errors
to treat any output as an error
Basic live migration was broken by the commit that added
non-shared block support in two ways:
1) It added a virCheckFlags() to doNativeMigrate(). Besides
the fact that typical usage of virCheckFlags() is in driver
entry points, and doNativeMigrate() is not an entry point,
it was missing important flags like VIR_MIGRATE_LIVE. Move
the virCheckFlags to the top-level qemuDomainMigratePrepare2
and friends.
2) It also added a memory leak in qemuMonitorTextMigrate()
by not freeing the memory used by virBufferContentAndReset().
This is fixed by storing the pointer in a temporary variable
and freeing it at the end.
With this patch in place, normal live migration works again.
v3: Instead of the churn for virCheckFlagsUI and UL, instead
always promote flags to an unsigned long and always use %lx
for the fprintf.
v2: Add back flags check, which required adding virCheckFlagsUI
and virCheckFlagsUL
Signed-off-by: Chris Lalancette <clalance@redhat.com>
The virDomainGetBlockInfo API allows query physical block
extent and allocated block extent. These are normally the
same value unless storing a special format like qcow2
inside a block device. In this scenario we can query QEMU
to get the actual allocated extent.
Since last time:
- Return fatal error in text monitor
- Only invoke monitor command for block devices
- Fix error handling JSON code
* src/qemu/qemu_driver.c: Fill in block aloction extent when VM
is running
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h,
src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h: Add
API to query the highest block extent via info blockstats
Approximately 60 messages were marked. Since these diagnostics are
intended solely for developers and maintainers, encouraging translation
is deemed to be counterproductive:
http://thread.gmane.org/gmane.comp.emulators.libvirt/25050/focus=25052
Run this command:
git grep -l VIR_WARN|xargs perl -pi -e \
's/(VIR_WARN0?)\s*\(_\((".*?")\)/$1($2/'
QEMU is gaining a new monitor command netdev_add for hotplugging
NICs using the netdev backend code. We already support this on
the command this, though it is disabled. This adds support for
hotplug too, also to remain disabled until 0.13 QEMU is released
* src/qemu/qemu_driver.c: Support netdev hotplug for NICs
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h,
src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h: Add
support for netdev_add and netdev_remove commands
Support for live migration between hosts that do not share storage was
added to qemu-kvm release 0.12.1.
It supports two flags:
-b migration without shared storage with full disk copy
-i migration without shared storage with incremental copy (same base image
shared between source and destination).
I tested the live migration without shared storage (both flags) for native
and p2p with and without tunnelling. I also verified that the fix doesn't
affect normal migration with shared storage.
The save process was relying on use of the shell >> append
operator to ensure the save data was placed after the libvirt
header + XML. This doesn't work for block devices though.
Replace this code with use of 'dd' and its 'seek' parameter.
This means that we need to pad the header + XML out to a
multiple of dd block size (in this case we choose 512).
The qemuMonitorMigateToCommand() monitor API is used for both
save/coredump, and migration via UNIX socket. We can't simply
switch this to use 'dd' since this causes problems with the
migration usage. Thus, create a dedicated qemuMonitorMigateToFile
which can accept an filename + offset, and remove the filename
from the current qemuMonitorMigateToCommand() API
* src/qemu/qemu_driver.c: Switch to qemuMonitorMigateToFile
for save and core dump
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h,
src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h: Create
a new qemuMonitorMigateToFile, separate from the existing
qemuMonitorMigateToCommand to allow handling file offsets
The text monitor code was checking for a '\n' prefix on several
places. Previously this would work, but since the monitor code
re-write the '\n' is already stripped off, so mustn't be checked
for.
* src/qemu/qemu_monitor_text.c: Fix monitor error checking
Probably as a result of a merge error, the CPU hotplug command
names were completely wrong.
* src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_text.c: Fix
the CPU hotplug command names
If either of the getfd or host_net_add monitor commands return
any text, this indicates an error condition. Don't ignore this!
* src/qemu/qemu_monitor_text.c: Report errors for getfd and
host_net_add
The parameter for the qemuMonitorDeviceDel() is a device alias,
not a device config string. Rename the parameter reflect this
and avoid confusion to readers.
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h,
src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h:
Rename devicestr to devalias in qemuMonitorDeviceDel()
Currently when we attempt to change the cdrom in a qemu VM the monitor
doesn't generate an error if the target filename doesn't exist. I've
submitted a patch[1] for this. This patch is the libvirt qemu-driver
side which catches the error message from the monitor and reportes the
error to libvirt. This means that virsh attach-disk cdrom commands
won't appear to succeed when qemu change command actually failed.
* src/qemu/qemu_monitor_text.c: in qemuMonitorTextChangeMedia() look
for failure to access the new data
virStrToLong* guarantees (via strtol) that the end pointer will be set
to the point at which parsing stopped (even on failure, this point is
the start of the input string).
* src/esx/esx_driver.c (esxGetVersion): Remove pointless
conditional.
* src/qemu/qemu_conf.c (qemuParseCommandLinePCI)
(qemuParseCommandLineUSB, qemuParseCommandLineSmp): Likewise.
* src/qemu/qemu_monitor_text.c
(qemuMonitorTextGetMigrationStatus): Likewise.
The code erroneously searched the entire "reply" for a comma, when
its intent was to search only that portion after "balloon: actual="
* src/qemu/qemu_monitor_text.c (qemuMonitorTextGetMemoryStats):
Search for "," only starting *after* the BALLOON_PREFIX string.
Otherwise, we'd be more prone to false positives.
QEMU has a monitor command 'set_cpu' which allows a specific
CPU to be toggled between online& offline state. libvirt CPU
hotplug does not work in terms of individual indexes CPUs.
Thus to support this, we iteratively toggle the online state
when the total number of vCPUs is adjusted via libvirt
NB, currently untested since QEMU segvs when running this!
* src/qemu/qemu_driver.c: Toggle online state for CPUs when
doing hotplug
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h,
src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h: Add
monitor API for toggling a CPU's online status via 'set_cpu
The code assumed that 'device_add' returned an empty string upon
success. This is not true, it sometimes prints random debug info.
THus we need to check for an explicit fail string
* src/qemu/qemu_monitor_text.c: Fix error checking of the device_add
monitor command
Introduce support for virDomainGetJobInfo in the QEMU driver. This
allows for monitoring of any API that uses the 'info migrate' monitor
command. ie virDomainMigrate, virDomainSave and virDomainCoreDump
Unfortunately QEMU does not provide a way to monitor incoming migration
so we can't wire up virDomainRestore yet.
The virsh tool gets a new command 'domjobinfo' to query status
* src/qemu/qemu_driver.c: Record virDomainJobInfo and start time
in qemuDomainObjPrivatePtr objects. Add generic shared handler
for calling 'info migrate' with all migration based APIs.
* src/qemu/qemu_monitor_text.c: Fix parsing of 'info migration' reply
* tools/virsh.c: add new 'domjobinfo' command to query progress
when the underlying qemu supports the drive/device model and the
controller has been added this way.
* src/qemu/qemu_driver.c: use qemuMonitorDelDevice() when detaching
PCI controller and if supported
* src/qemu/qemu_monitor.[ch]: add new qemuMonitorDelDevice() function
* src/qemu/qemu_monitor_json.[ch]: JSON backend for DelDevice command
* src/qemu/qemu_monitor_text.[ch]: Text backend for DelDevice command
The old text mode monitor prompts for a password when disks are
encrypted. This interactive approach doesn't work for JSON mode
monitor. Thus there is a new 'block_passwd' command that can be
used.
* src/qemu/qemu_driver.c: Split out code for looking up a disk
secret from findVolumeQcowPassphrase, into a new method
getVolumeQcowPassphrase. Enhance qemuInitPasswords() to also
set the disk encryption password via the monitor
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h,
src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h: Add
support for the 'block_passwd' monitor command.
With QEMU >= 0.12 the host and guest side of disks no longer have
the same naming convention. Specifically the host side will now
get a 'drive-' prefix added to its name. The 'info blockstats'
monitor command returns the host side name, so it is neccessary
to strip this off when looking up stats since libvirt stores the
guest side name !
* src/qemu/qemu_conf.c, src/qemu/qemu_conf.h: Move 'drive-' prefix
string to a defined constant
* src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_text.c: Strip
off 'drive-' prefix (if found) when looking up disk stats
The way QEMU is started has been changed to use '-device' and
the new style '-drive' syntax. This needs to be mirrored in
the hotplug code, requiring addition of two new APIs.
* src/qemu/qemu_monitor.h, src/qemu/qemu_monitor.c: Define APIs
qemuMonitorAddDevice() and qemuMonitorAddDrive()
* src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h,
src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h:
Implement the new monitor APIs
* src/qemu/qemu_monitor_text.c (qemuMonitorTextAttachDrive): Most other
failures in this function would "goto cleanup", but one mistakenly
returned directly, skipping the cleanup and resulting in a leak.
In addition, iterating the "try_command" loop would clobber, and
thus leak, the "cmd" allocated on the first iteration,
so be careful to free it in addition to "reply" beforehand.
Fix a small problem with the qemu memory stats parsing algorithm. If qemu
reports a stat that libvirt does not recognize, skip past it so parsing can
continue. This corrects a potential infinite loop in the parsing code that can
only be triggered if new statistics are added to qemu.
* src/qemu/qemu_monitor_text.c: qemuMonitorParseExtraBalloonInfo add a
skip for extra ','
I noticed some debug messages are printed with an empty lines after
them. This patch removes these empty lines from all invocations of the
following macros:
VIR_DEBUG
VIR_DEBUG0
VIR_ERROR
VIR_ERROR0
VIR_INFO
VIR_WARN
VIR_WARN0
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Hotunplug of devices requires that we know their PCI address. Even
hotplug of SCSI drives, required that we know the PCI address of
the SCSI controller to attach the drive to. We can find this out
by running 'info pci' and then correlating the vendor/product IDs
with the devices we booted with.
Although this approach is somewhat fragile, it is the only viable
option with QEMU < 0.12, since there is no way for libvirto set
explicit PCI addresses when creating devices in the first place.
For QEMU > 0.12, this code will not be used.
* src/qemu/qemu_driver.c: Assign all dynamic PCI addresses on
startup of QEMU VM, matching vendor/product IDs
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h,
src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h: Add
API for fetching PCI device address mapping
The current SCSI hotplug support attaches a brand new SCSI controller
for every disk. This is broken because the semantics differ from those
used when starting the VM initially. In the latter case, each SCSI
controller is filled before a new one is added.
If the user specifies an high drive index (sdazz) then at initial
startup, many intermediate SCSI controllers may be added with no
drives.
This patch changes SCSI hotplug so that it exactly matches the
behaviour of initial startup. First the SCSI controller number is
determined for the drive to be hotplugged. If any controller upto
and including that controller number is not yet present, it is
attached. Then finally the drive is attached to the last controller.
NB, this breaks SCSI hotunplug, because there is no 'drive_del'
command in current QEMU. Previous SCSI hotunplug was broken in
any case because it was unplugging the entire controller, not
just the drive in question.
A future QEMU will allow proper SCSI hotunplug of a drive.
This patch is derived from work done by Wolfgang Mauerer on disk
controllers.
* src/qemu/qemu_driver.c: Fix SCSI hotplug to add a drive to
the correct controller, instead of just attaching a new
controller.
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h,
src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h: Add
support for 'drive_add' command
This patch allows for explicit hotplug/unplug of SCSI controllers.
Ordinarily this is not required, since QEMU/libvirt will attach
a new SCSI controller whenever one is required. Allowing explicit
hotplug of controllers though, enables the caller to specify a
static PCI address, instead of auto-assigning the next available
PCI slot. Or it will when we have static PCI addressing.
This patch is derived from Wolfgang Mauerer's disk controller
patch series.
* src/qemu/qemu_driver.c: Support hotplug & unplug of SCSI
controllers
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h,
src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h: Add
new API for attaching PCI SCSI controllers
Convert the QEMU monitor APIs over to use virDomainDeviceAddress
structs for passing addresses in/out, instead of individual bits.
This makes the number of parameters smaller & easier to deal with.
No functional change
* src/qemu/qemu_driver.c, src/qemu/qemu_monitor.c,
src/qemu/qemu_monitor.h, src/qemu/qemu_monitor_text.c,
src/qemu/qemu_monitor_text.h: Change monitor hotplug APIs to
take an explicit address ptr for all host/guest addresses
