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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