Quoting Tomoki Sekiyama (2014-05-22 08:56:53)
> When an array of mount point paths is specified as 'mountpoints' argument
> of guest-fsfreeze-freeze, qemu-ga with this patch will only freeze the file
> systems mounted on specified paths in Linux.
> This would be useful when the host wants to create partial disk snapshots.
Since this isn't really applicable for win32, and it's hard to discover
optional params via guest-info without some extensive changes to how we handle
capabilities negotiation, I think it makes more sense to introduce a new
command for this, something like guest-fsfreeze-freeze-filesystems, which we
can easily discover and properly mark as unsupported on win32.
Other than that looks good.
>
> Signed-off-by: Tomoki Sekiyama <tomoki.sekiy...@hds.com>
> ---
> qga/commands-posix.c | 17 ++++++++++++++++-
> qga/commands-win32.c | 3 ++-
> qga/qapi-schema.json | 4 ++++
> 3 files changed, 22 insertions(+), 2 deletions(-)
>
> diff --git a/qga/commands-posix.c b/qga/commands-posix.c
> index 34ddba0..771f00c 100644
> --- a/qga/commands-posix.c
> +++ b/qga/commands-posix.c
> @@ -714,9 +714,11 @@ GuestFsfreezeStatus qmp_guest_fsfreeze_status(Error
> **errp)
> * Walk list of mounted file systems in the guest, and freeze the ones which
> * are real local file systems.
> */
> -int64_t qmp_guest_fsfreeze_freeze(Error **errp)
> +int64_t qmp_guest_fsfreeze_freeze(bool has_mountpoints, strList *mountpoints,
> + Error **errp)
> {
> int ret = 0, i = 0;
> + strList *list;
> FsMountList mounts;
> struct FsMount *mount;
> Error *local_err = NULL;
> @@ -741,6 +743,19 @@ int64_t qmp_guest_fsfreeze_freeze(Error **errp)
> ga_set_frozen(ga_state);
>
> QTAILQ_FOREACH_REVERSE(mount, &mounts, FsMountList, next) {
> + /* To issue fsfreeze in the reverse order of mounts, check if the
> + * mount is listed in the list here */
> + if (has_mountpoints) {
> + for (list = mountpoints; list; list = list->next) {
> + if (strcmp(list->value, mount->dirname) == 0) {
> + break;
> + }
> + }
> + if (!list) {
> + continue;
> + }
> + }
> +
> fd = qemu_open(mount->dirname, O_RDONLY);
> if (fd == -1) {
> error_setg_errno(errp, errno, "failed to open %s",
> mount->dirname);
> diff --git a/qga/commands-win32.c b/qga/commands-win32.c
> index d793dd0..0c6296d 100644
> --- a/qga/commands-win32.c
> +++ b/qga/commands-win32.c
> @@ -171,7 +171,8 @@ GuestFsfreezeStatus qmp_guest_fsfreeze_status(Error
> **errp)
> * Freeze local file systems using Volume Shadow-copy Service.
> * The frozen state is limited for up to 10 seconds by VSS.
> */
> -int64_t qmp_guest_fsfreeze_freeze(Error **errp)
> +int64_t qmp_guest_fsfreeze_freeze(bool has_mountpoints, strList *mountpoints,
> + Error **errp)
> {
> int i;
> Error *local_err = NULL;
> diff --git a/qga/qapi-schema.json b/qga/qapi-schema.json
> index a8cdcb3..31c0dc8 100644
> --- a/qga/qapi-schema.json
> +++ b/qga/qapi-schema.json
> @@ -378,12 +378,16 @@
> #
> # Sync and freeze all freezable, local guest filesystems
> #
> +# @mountpoints: #optional an array of mountpoints of filesystems to be
> frozen.
> +# If omitted, every mounted filesystem is frozen. (Since: 2.1)
> +#
> # Returns: Number of file systems currently frozen. On error, all filesystems
> # will be thawed.
> #
> # Since: 0.15.0
> ##
> { 'command': 'guest-fsfreeze-freeze',
> + 'data': { '*mountpoints': ['str'] },
> 'returns': 'int' }
>
> ##
