[Qemu-devel] [V2 0/2]Qemu: Enable dynamic hostcache change through monitor

[Supriya Kannery]

  Currently host page cache setting for a block device cannot be changed
without restarting a running VM. Following patchset [V2] is for enabling 
dynamic change of host cache setting for devices through qemu monitor.

Changes from patchset V1:
1. Support of dynamic cache change only for hostcache.
2. Monitor command "hostcache_get" added to display current cache setting
3. Backed off the changes for display of cache setting in "info block"

Two new monitor commands added.
1. hostcache_get 
    -- Displays hostcache setting of a block device.
Usage:
"hostcache_get <device>
   <device> = block device

2. hostcache_set
    -- Sets hostcache for the device to specified value.
Usage:
"hostcache_set <device> <cache>"
   <device> = block device      
   <cache> = "on"/"off"

1/2 New error classes for file reopen and device insertion
2/2 Add commands "hostcache_set" and "hostcache_get" 
     
 block.c         |   48 ++++++++++++++++++++++++++++++++++++++++++++++++
 block.h         |    2 ++
 blockdev.c      |   48 ++++++++++++++++++++++++++++++++++++++++++++++++
 blockdev.h      |    2 ++
 hmp-commands.hx |   29 +++++++++++++++++++++++++++++
 qerror.c        |    8 ++++++++
 qerror.h        |    6 ++++++
 qmp-commands.hx |   55 
 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 8 files changed, 198 insertions(+)
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