diff options
| author | Ryan Harper <ryanh@us.ibm.com> | 2010-11-12 11:07:13 -0600 |
|---|---|---|
| committer | Kevin Wolf <kwolf@redhat.com> | 2010-11-24 17:30:19 +0100 |
| commit | 9063f81415f3518ef8206e74085c2a92c96890a0 (patch) | |
| tree | ac5eb775dea385bff21fce6f063eb0348e413217 /hmp-commands.hx | |
| parent | 6fa2c95f279dda62aa7e3292cc424ff3fab6a602 (diff) | |
Implement drive_del to decouple block removal from device removal
Currently device hotplug removal code is tied to device removal via
ACPI. All pci devices that are removable via device_del() require the
guest to respond to the request. In some cases the guest may not
respond leaving the device still accessible to the guest. The management
layer doesn't currently have a reliable way to revoke access to host
resource in the presence of an uncooperative guest.
This patch implements a new monitor command, drive_del, which
provides an explicit command to revoke access to a host block device.
drive_del first quiesces the block device (qemu_aio_flush;
bdrv_flush() and bdrv_close()). This prevents further IO from being
submitted against the host device. Finally, drive_del cleans up
pointers between the drive object (host resource) and the device
object (guest resource).
Signed-off-by: Ryan Harper <ryanh@us.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Diffstat (limited to 'hmp-commands.hx')
| -rw-r--r-- | hmp-commands.hx | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/hmp-commands.hx b/hmp-commands.hx index e5585ba0e9..23024ba6f2 100644 --- a/hmp-commands.hx +++ b/hmp-commands.hx @@ -68,6 +68,24 @@ Eject a removable medium (use -f to force it). ETEXI { + .name = "drive_del", + .args_type = "id:s", + .params = "device", + .help = "remove host block device", + .user_print = monitor_user_noop, + .mhandler.cmd_new = do_drive_del, + }, + +STEXI +@item drive_del @var{device} +@findex drive_del +Remove host block device. The result is that guest generated IO is no longer +submitted against the host device underlying the disk. Once a drive has +been deleted, the QEMU Block layer returns -EIO which results in IO +errors in the guest for applications that are reading/writing to the device. +ETEXI + + { .name = "change", .args_type = "device:B,target:F,arg:s?", .params = "device filename [format]", |