QEMU 0.13 introduced cache=unsafe for -drive, this patch exposes
it in the libvirt layer.

  * Introduced a new QEMU capability flag ($prefix_CACHE_UNSAFE),
    as even if $prefix_CACHE_V2 is set, we can't know if unsafe
    is supported.

  * Improved the reliability of qemu cache type detection.

Commit 0a22f542 added --min-guarantee option for the memtune command.
This option is supported only by the ESX hypervisor. This patch adds a
statement about this fact, to prevent user confusion.

This patch also adds explanation how to clear/set to unlimited the
memory tunables. (documments the -1 value).

Virsh man page lists driver types to be used with attach-device
command, but does not specify that those are usable only with the XEN
Hypervisor.

This patch adds statement, that those options specified are applicable
only on the Xen hypervisor and adds option usable with qemu emulator.

This patch also changes type of error returned by QEMU driver if the
user specifies incompatible driver type from VIR_ERR_INTERNAL_ERROR to
VIR_ERR_CONFIG_UNSUPPORTED.

Users of virsh complain that output of the domblkstat command
is not intuitive enough. This patch adds explanation of fields
returned by this command to the help section for domblkstat and
the man page of virsh. Also a switch --human is added for
domblkstat that prints the fields with more descriptive
texts.

This patch also changes sequence of the output fields and their
names back to the order and spelling established by previous
versions of virsh to maintain compatibility with scripts.

Example of ordered and "translated" output:

PRE-patch:

virsh # domblkstat 1 vda
vda wr_bytes 5170176
vda wr_operations 511
vda rd_bytes 82815488
vda rd_operations 3726

POST-patch:

virsh # domblkstat 1 vda
vda rd_req 3726
vda rd_bytes 82815488
vda wr_req 478
vda wr_bytes 4965376

Example of human readable output:

virsh # domblkstat 1 vda --human
Device: vda
 number of read operations:      3726
 number of read bytes:           82815488
 number of write operations:     478
 number of bytes written:        4965376

https://bugzilla.redhat.com/show_bug.cgi?id=731656

Documentation did not specify, that some permissions are required on
target path for coredump for the user running the hypervisor.

Diff to v1:
- reword statements

With this patch, it is hopefully a bit more obvious that for
snapshot-create-as, a literal '--diskspec' is mandatory if name
or description was omitted, but optional if all earlier options
were provided.

These all denote two diskspecs and a description:
virsh snapshot-create-as dom name desc vda vdb
virsh snapshot-create-as dom name desc --diskspec vda --diskspec vdb
virsh snapshot-create-as dom name desc --diskspec vda vdb
virsh snapshot-create-as dom name desc vda --diskspec vdb
virsh snapshot-create-as dom --diskspec vda --diskspec vdb name desc

This gives two diskspecs but no description:
virsh snapshot-create-as dom name --diskspec vda --diskspec vdb

And this treats 'vda' as the description, with only one diskspec:
virsh snapshot-create-as dom name vda vdb

The help output now shows:
    snapshot-create-as <domain> [<name>] [<description>] [--print-xml] [--no-metadata] [--halt] [--disk-only] [[--diskspec] <string>]...

I also checked the help output for echo and send-key, which are two
other variants of argv commands.

* tools/virsh.pod (snapshot-create-as): Document when a literal
--diskspec must preceed a diskspec argument.
* tools/virsh.c (vshCmddefHelp): Update help output for argv when
naming the option is useful.
(vshCmddefGetData): Fix logic on when argv was seen.
* tests/virsh-optparse: Add tests to avoid regressions.

Fix cut&paste error having command named domif-setlink instead of
domif-getlink.

* tools/virsh.pod: fix a option typo of send-key section.
Signed-off-by: NAlex Jia <ajia@redhat.com>

Two new commands are added to virsh that wrap usage of
virDomainUpdateDeviceFlags for changing link state of domain's network
interfaces. These wrappers extract network devices's xml configuration
and modify the link state for easy manipulation from an user's perspective.

 - domif-setlink - set link state of a domains virtual network interface
 - domif-getlink - get link state

* tools/virsh.c   - Add functionality to virsh
* tools/virsh.pod - Manpage documentation

Expose the disk-only flag through virsh.  Additionally, make
virsh snapshot-create-as take an arbitrary number of diskspecs,
which can be used to build up the xml for <domainsnapshot>.

* tools/virsh.c (cmdSnapshotCreate): Add --disk-only.
(cmdSnapshotCreateAs): Likewise, and add argv diskspec.
(vshParseSnapshotDiskspec): New helper function.
(vshCmddefGetOption): Allow naming of argv field.
* tools/virsh.pod (snapshot-create, snapshot-create-as): Document
them.
* tests/virsh-optparse: Test snapshot-create-as parsing.

This adds a convenience function to virsh that parses out block
information from the domain xml, making it much easier to see
what strings can be used in all other contexts that demand a
specific block name, especially when given the previous patch
that allows using either target or unique source name.

As an example on a domain with one disk and an empty cdrom drive:

Target     Source
-------------------------------------------
vda        /var/lib/libvirt/images/fedora_12.img
hdc        -

* tools/virsh.c (cmdDomblklist): New function.
* tools/virsh.pod (domblklist): Document it.

I got confused when 'virsh domblkinfo dom disk' required the
path to a disk (which can be ambiguous, since a single file
can back multiple disks), rather than the unambiguous target
device name that I was using in disk snapshots.  So, in true
developer fashion, I went for the best of both worlds - all
interfaces that operate on a disk (aka block) now accept
either the target name or the unambiguous path to the backing
file used by the disk.

* src/conf/domain_conf.h (virDomainDiskIndexByName): Add
parameter.
(virDomainDiskPathByName): New prototype.
* src/libvirt_private.syms (domain_conf.h): Export it.
* src/conf/domain_conf.c (virDomainDiskIndexByName): Also allow
searching by path, and decide whether ambiguity is okay.
(virDomainDiskPathByName): New function.
(virDomainDiskRemoveByName, virDomainSnapshotAlignDisks): Update
callers.
* src/qemu/qemu_driver.c (qemudDomainBlockPeek)
(qemuDomainAttachDeviceConfig, qemuDomainUpdateDeviceConfig)
(qemuDomainGetBlockInfo, qemuDiskPathToAlias): Likewise.
* src/qemu/qemu_process.c (qemuProcessFindDomainDiskByPath):
Likewise.
* src/libxl/libxl_driver.c (libxlDomainAttachDeviceDiskLive)
(libxlDomainDetachDeviceDiskLive, libxlDomainAttachDeviceConfig)
(libxlDomainUpdateDeviceConfig): Likewise.
* src/uml/uml_driver.c (umlDomainBlockPeek): Likewise.
* src/xen/xend_internal.c (xenDaemonDomainBlockPeek): Likewise.
* docs/formatsnapshot.html.in: Update documentation.
* tools/virsh.pod (domblkstat, domblkinfo): Likewise.
* docs/schemas/domaincommon.rng (diskTarget): Tighten pattern on
disk targets.
* docs/schemas/domainsnapshot.rng (disksnapshot): Update to match.
* tests/domainsnapshotxml2xmlin/disk_snapshot.xml: Update test.

Easy enough to emulate even with older servers.

* tools/virsh.c (cmdSnapshotCreate, cmdSnapshotCreateAs): Add
--halt flag.
(vshSnapshotCreate): Emulate halt when flag is unsupported.
* tools/virsh.pod (snapshot-create, snapshot-create-as): Document
it.

It would technically be possible to have virsh compute the list
of descendants of a given snapshot, then delete those one at
a time.  But it's complex, and not worth writing for a first
cut at implementing the new flags.

* tools/virsh.c (cmdSnapshotDelete): Add --children-only,
--metadata.
* tools/virsh.pod (snapshot-delete): Document them.

Similar to 'undefine --managed-save' (commit 83e849c1), we must
assume that the old API is unsafe; however, we cannot emulate
metadata-only deletion on older servers.  Additionally, we have
the wrinkle that while virDomainUndefineFlags and managed save
cleanup were introduced in 0.9.4, it wasn't until 0.9.5 that
snapshots block undefine of a domain.  Do the best we can given
the server we are talking to.

* tools/virsh.c (cmdUndefine): Add --snapshots-metadata flag.
* tools/virsh.pod (undefine, destroy, shutdown): Document effect
of snapshots.

Wire up the new snapshot creation flags in virsh.  For convenience,
teach 'snapshot-current' how to make an existing snapshot become
current (can be used after upgrading to newer libvirt to recover
from the fact that the older libvirt lost track of the current
snapshot after a restart).  The snapshot-create-as command is
intentionally not taught --redefine or --current, as this would
imply adding a lot of other options for everything else that can
appear in the <domainsnapshot> xml, but which is normally read-only.
Besides, redefining will usually be done on files created by
snapshot-dumpxml, rather than something built up by hand on the
command line.  And now that we can redefine, we can edit.

* tools/virsh.c (cmdSnapshotCreate): Add --redefine, --current,
and --no-metadata.
(cmdSnapshotCreateAs): Add --no-metadata.
(cmdSnapshotCurrent): Add snapshotname to alter current snapshot.
(cmdSnapshotEdit): New command.
* tools/virsh.pod (snapshot-create, snapshot-create-as)
(snapshot-current, snapshot-edit):  Document these.

New flag bits are worth exposing via virsh.  In the case of
snapshot-list --roots, it's possible to emulate this even when
talking to an older server that lacks the bit; whereas
--metadata requires a newer server.

Although we don't use --security-info yet, the flag is already
documented for other dumpxml operations, and turning it on now
will make it useful when a future patch actually has to honor it.

* tools/virsh.c (cmdSnapshotDumpXML, cmdSnapshotCurrent): Add
--security-info.
(cmdSnapshotList): Add --roots, --metadata.
* tools/virsh.pod (snapshot-dumpxml, snapshot-current)
(snapshot-list): Document these.

Even though I recently added 'virsh snapshot-parent', doing it one
snapshot at a time is painful, so make it possible to expand the
snapshot-list table at once.

* tools/virsh.c (cmdSnapshotList): Add --parent.
* tools/virsh.pod (snapshot-list): Document it.

Pretty straight-forward exposure of new flags.  For most commands,
we let the API reject mutually exclusive flags; but for save-image-edit,
we do the sanity check ourselves to avoid looping on flag failure if
the edit cycle is ever enhanced to allow the user to retry an edit
to fix up an xml validation error.

* tools/virsh.c (cmdManagedSave, cmdRestore, cmdSave)
(cmdSaveImageDefine, cmdSaveImageEdit): Add new flags.
* tools/virsh.pod (managedsave, restore, save, save-image-define)
(save-image-edit): Document them.

Newer QEMU introduced cache=directsync for -drive, this patchset
is to expose it in libvirt layer.

  * Introduced a new QEMU capability flag ($prefix_CACHE_DIRECTSYNC),
    As even $prefix_CACHE_V2 is set, we can't known if directsync
    is supported.

The 'virsh man' description of send-key was incomplete and used the
old style (literal 'optional name' instead of '[name]' metasyntax).
Meanwhile, none of the other virsh help texts include examples, so
I moved it out of virsh help and into the man page.

* tools/virsh.pod (send-key): Give better details.
* tools/virsh.c (info_send_key): Drop example from here.

There have been several instances of people having problems with
a broken managed save file, and not aware that they could use
'virsh managedsave-remove dom' to fix things.  Making it possible
to do this as part of starting a domain makes the same functionality
easier to find, and one less API call.

* include/libvirt/libvirt.h.in (VIR_DOMAIN_START_FORCE_BOOT): New
flag.
* src/libvirt.c (virDomainCreateWithFlags): Document it.
* src/qemu/qemu_driver.c (qemuDomainObjStart): Alter signature.
(qemuAutostartDomain, qemuDomainStartWithFlags): Update callers.
* tools/virsh.c (cmdStart): Expose it in virsh.
* tools/virsh.pod (start): Document it.

This patch updates the man page about virsh schedinfo command.

 - fix typo: 1844674407370955 -> 18446744073709551
 - describe the value 0 of vcpu_period and vcpu_quota parameters
Signed-off-by: NTaku Izumi <izumi.taku@jp.fujitsu.com>

The default is 4, not 0.

Knowing whether 'virsh start' will resume a saved image or do
a fresh boot is useful enough to expose via 'virsh list'.

Also, translate the state column.

* tools/virsh.c (cmdList): add --managed-save flag
* tools/virsh.pod (list): Document it.
Based on a suggestion by Miklos Vajna.

This patch adds the missing documentation about the scheduler parameter
"vcpu_period" and "vcpu_quota".

Call me lazy, but:

virsh qemu-monitor-command dom --hmp info status

is nicer than:

virsh qemu-monitor-command dom --hmp 'info status'

* tools/virsh.c (cmdQemuMonitorCommand): Allow multiple arguments,
for convenience.

Down the road, I want to add virDomainSnapshotGetParent, and use
the new API rather than xml scraping; but this virsh command can
be implemented even without the new API.

* tools/virsh.c (cmdSnapshotParent): New command.
* tools/virsh.pod (snapshot-parent): Document it.

Sometimes, full XML is too much; since most snapshot commands
operate on a snapshot name, there should be an easy way to get
at the current snapshot's name.  For example:

virsh snapshot-revert dom `virsh snapshot-current dom --name`

* tools/virsh.c (cmdSnapshotCurrent): Add an option.
* tools/virsh.pod (snapshot-current): Document it.

* tools/virsh.pod: change 'live' to 'abort' based on actual option

* tools/virsh.c (doMigrate): Add --change-protection flag.
* tools/virsh.pod (migrate): Document it.

Commit b31abc6f introduce commands blockpull and blockjob, but
forgot to add the docs meanwhile.

The description of the list command seemed to suggest that it could
take a set of domains as an argument, which is not correct in the
current HEAD.  If virsh list is intended to take a list of domains,
then this patch should be NAK'd and a bug opened against virsh list.

Reported by hachi on #virt

v2:

Change language to include transient domains

Osier pointed out that transient domains are not defined, so what I
had originally proposed wasn't quite correct.

* tools/virsh.pod: Fix missing > tag in docs

Rename the existing --current flag to the new name --active,
while adding a new flag --current to expose the new
VIR_DOMAIN_AFFECT_CURRENT flag of virDomainGetVcpusFlags.

For backwards compability, the output does not change (even
though the label "current" no longer matches the spelling of
the option that would trigger that number in isolation), and
we accept "--current --live" as an undocumented synonym for
"--active --live" to avoid breaking any existing clients.

* tools/virsh.c (cmdVcpucount): Add --active flag, and rearrange
existing flag handling to expose VIR_DOMAIN_AFFECT_CURRENT support.
* tools/virsh.pod (vcpucount): Document this.

Now you can edit a saved state file even if you forgot to grab
a dumpxml file prior to saving a domain.  Plus, in-place editing
feels so much nicer.

* tools/virsh.c (cmdSaveImageDumpxml, cmdSaveImageDefine)
(cmdSaveImageEdit): New commands.
* tools/virsh.pod (save-image-dumpxml, save-image-define)
(save-image-edit): Document them.

Also, migrate was missing documentation for the --xml option
added in commit ec5301cb.

* tools/virsh.c (cmdSave, cmdRestore): Add xml argument.
* tools/virsh.pod (save, restore, migrate): Document it.

Wire up the new flag to several virsh commands.  Also, the
'dump' command had undocumented flags.

* tools/virsh.c (cmdSave, cmdManagedSave, cmdDump, cmdStart)
(cmdRestore): Add new flag.
* tools/virsh.pod (save, managedsave, dump, start, restore):
Document flags.