[Qemu-devel] [PATCH V13 0/6] enhancement for qmp/hmp interfaces of block info

[Wenchao Xia <xiawenc@linux.vnet.ibm.com>]

  This serial let qmp interface show delaied info, including internal snapshot
/backing chain on all block device at runtime, which helps management stack and
human user, by retrieving exactly the same info of what qemu saws.

Example:
-> { "execute": "query-block" }
<- {
      "return":[
         {
            "io-status": "ok",
            "device":"ide0-hd0",
            "locked":false,
            "removable":false,
            "inserted":{
               "ro":false,
               "drv":"qcow2",
               "encrypted":false,
               "file":"disks/test.qcow2",
               "backing_file_depth":1,
               "bps":1000000,
               "bps_rd":0,
               "bps_wr":0,
               "iops":1000000,
               "iops_rd":0,
               "iops_wr":0,
               "image":{
                  "filename":"disks/test.qcow2",
                  "format":"qcow2",
                  "virtual-size":2048000,
                  "backing_file":"base.qcow2",
                  "full-backing-filename":"disks/base.qcow2",
                  "backing-filename-format:"qcow2",
                  "snapshots":[
                     {
                        "id": "1",
                        "name": "snapshot1",
                        "vm-state-size": 0,
                        "date-sec": 10000200,
                        "date-nsec": 12,
                        "vm-clock-sec": 206,
                        "vm-clock-nsec": 30
                     }
                  ],
                  "backing-image":{
                      "filename":"disks/base.qcow2",
                      "format":"qcow2",
                      "virtual-size":2048000
                  }
               }
            },
            "type":"unknown"
         },
         {
            "io-status": "ok",
            "device":"ide1-cd0",
            "locked":false,
            "removable":true,
            "type":"unknown"
         },
         {
            "device":"floppy0",
            "locked":false,
            "removable":true,
            "type":"unknown"
         },
         {
            "device":"sd0",
            "locked":false,
            "removable":true,
            "type":"unknown"
         }
      ]
   }

  These patches follows the rule that use qmp to retieve information,
hmp layer just does a translation from qmp object it got. To make code
graceful, snapshot and image info retrieving code in qemu and qemu-img are
merged into block layer, and some function name was adjusted to make it tips
better. For the part touch by the serial, it works as:

   qemu          qemu-img

dump_monitor    dump_stdout
     |--------------| 
            |
       block/qapi.c

  Special thanks for Markus, Stefan, Kevin, Eric reviewing many times.

v13:
  Renamed the serial as "enhancement for qmp/hmp interfaces of block info".
  Seperated the common part of code moving and hmp printf as a standalone
serial, which can be used by both mine and Pavel's work. This serial depend
on it: "[PATCH V3 0/4] qapi and snapshot code clean up in block layer",
https://lists.gnu.org/archive/html/qemu-devel/2013-05/msg03539.html
  Removed the VM snapshot info part, since it relate to VM snapshot creating
logic, which should be changed together with Pavel's serial.
  Address Eric's comments:
  2/6: bdrv_query_image_info() returns void now, only use *errp to tip error.

Wenchao Xia (6):
  1 block: add snapshot info query function bdrv_query_snapshot_info_list()
  2 block: add image info query function bdrv_query_image_info()
  3 qmp: add recursive member in ImageInfo
  4 qmp: add ImageInfo in BlockDeviceInfo used by query-block
  5 hmp: show ImageInfo in 'info block'
  6 hmp: add parameters device and -v for info block

 block/qapi.c         |  148 ++++++++++++++++++++++++++++++++++++++++++--------
 hmp.c                |   21 +++++++
 include/block/qapi.h |   14 +++--
 monitor.c            |    7 ++-
 qapi-schema.json     |   10 +++-
 qemu-img.c           |   10 +++-
 qmp-commands.hx      |   69 +++++++++++++++++++++++-
 7 files changed, 242 insertions(+), 37 deletions(-)