On 09/18/12 00:08, Eric Blake wrote:
The wait loop logic borrows heavily from blockcommit.
Maybe a little too sparse on the commit message, but the man page
addition makes it up.
* tools/virsh-domain.c (cmdBlockCommit): New function.
* tools/virsh.pod (blockcommit): Document it.
---
tools/virsh-domain.c | 153 ++++++++++++++++++++++++++++++++++++++++++++++++++-
tools/virsh.pod | 30 ++++++++++
2 files changed, 182 insertions(+), 1 deletion(-)
diff --git a/tools/virsh-domain.c b/tools/virsh-domain.c
index b6de9a8..aa23011 100644
--- a/tools/virsh-domain.c
+++ b/tools/virsh-domain.c
@@ -1260,6 +1272,144 @@ static void vshCatchInt(int sig ATTRIBUTE_UNUSED,
}
/*
+ * "blockcommit" command
+ */
+static const vshCmdInfo info_block_commit[] = {
+ {"help", N_("Start a block commit operation.")},
+ {"desc", N_("Commit changes from a snapshot down to its backing
image.")},
+ {NULL, NULL}
+};
+
+static const vshCmdOptDef opts_block_commit[] = {
+ {"domain", VSH_OT_DATA, VSH_OFLAG_REQ, N_("domain name, id or
uuid")},
+ {"path", VSH_OT_DATA, VSH_OFLAG_REQ, N_("fully-qualified path of
disk")},
The API says you can use "vda" and similar, is that considered
fully-qualified? / this question was answered below /
+ {"bandwidth", VSH_OT_DATA, VSH_OFLAG_NONE,
N_("bandwidth limit in MiB/s")},
Megabits look like a reasonable granularity to limit this. Well maybe
apart from testing purposes where somebody would like to do it really
slow to be able to poke around.
+ {"base", VSH_OT_DATA, VSH_OFLAG_NONE,
+ N_("path of base file to commit into (default bottom of chain)")},
+ {"shallow", VSH_OT_BOOL, 0, N_("use backing file of top as
base")},
+ {"top", VSH_OT_DATA, VSH_OFLAG_NONE,
+ N_("path of top file to commit from (default top of chain)")},
+ {"delete", VSH_OT_BOOL, 0,
+ N_("delete files that were successfully committed")},
+ {"wait", VSH_OT_BOOL, 0, N_("wait for job to complete")},
+ {"verbose", VSH_OT_BOOL, 0, N_("with --wait, display the
progress")},
+ {"timeout", VSH_OT_INT, VSH_OFLAG_NONE,
+ N_("with --wait, abort if copy exceeds timeout (in seconds)")},
+ {NULL, 0, 0, NULL}
+};
+
+static bool
+cmdBlockCommit(vshControl *ctl, const vshCmd *cmd)
+{
+ virDomainPtr dom = NULL;
+ bool ret = false;
+ bool blocking = vshCommandOptBool(cmd, "wait");
+ bool verbose = vshCommandOptBool(cmd, "verbose");
+ int timeout = 0;
+ struct sigaction sig_action;
+ struct sigaction old_sig_action;
+ sigset_t sigmask;
+ struct timeval start;
+ struct timeval curr;
+ const char *path = NULL;
+ bool quit = false;
+ int abort_flags = 0;
+
+ if (blocking) {
+ if (vshCommandOptInt(cmd, "timeout", &timeout) > 0) {
+ if (timeout < 1) {
+ vshError(ctl, "%s", _("invalid timeout"));
+ return false;
+ }
+
+ /* Ensure that we can multiply by 1000 without overflowing. */
+ if (timeout > INT_MAX / 1000) {
+ vshError(ctl, "%s", _("timeout is too big"));
+ return false;
+ }
+ }
+ if (vshCommandOptString(cmd, "path", &path) < 0)
+ return false;
+ if (vshCommandOptBool(cmd, "async"))
+ abort_flags |= VIR_DOMAIN_BLOCK_JOB_ABORT_ASYNC;
+
+ sigemptyset(&sigmask);
+ sigaddset(&sigmask, SIGINT);
+
+ intCaught = 0;
+ sig_action.sa_sigaction = vshCatchInt;
+ sig_action.sa_flags = SA_SIGINFO;
+ sigemptyset(&sig_action.sa_mask);
+ sigaction(SIGINT, &sig_action, &old_sig_action);
+
+ GETTIMEOFDAY(&start);
+ } else if (verbose || vshCommandOptBool(cmd, "timeout") ||
+ vshCommandOptBool(cmd, "async")) {
+ vshError(ctl, "%s", _("blocking control options require
--wait"));
This error message isn't 100% clear on the first read. What about:
"--verbose and --timeout require --wait" ?
+ return false;
+ }
+
+ if (blockJobImpl(ctl, cmd, NULL, VSH_CMD_BLOCK_JOB_COMMIT, &dom) < 0)
+ goto cleanup;
+
+ if (!blocking) {
+ vshPrint(ctl, "%s", _("Block Commit started"));
+ ret = true;
+ goto cleanup;
+ }
+
+ while (blocking) {
+ virDomainBlockJobInfo info;
+ int result = virDomainGetBlockJobInfo(dom, path, &info, 0);
+
+ if (result < 0) {
+ vshError(ctl, _("failed to query job for disk %s"), path);
+ goto cleanup;
+ }
+ if (result == 0)
+ break;
+
+ if (verbose)
+ print_job_progress(_("Block Commit"),
+ info.end - info.cur, info.end);
+
+ GETTIMEOFDAY(&curr);
+ if (intCaught || (timeout &&
+ (((int)(curr.tv_sec - start.tv_sec) * 1000 +
+ (int)(curr.tv_usec - start.tv_usec) / 1000) >
+ timeout * 1000))) {
Wouldn't it be better to multiply timeout by 1000 at the beginning and
not bother re-doing it on every iteration?
+ vshDebug(ctl, VSH_ERR_DEBUG,
+ intCaught ? "interrupted" : "timeout");
+ intCaught = 0;
+ timeout = 0;
+ quit = true;
+ if (virDomainBlockJobAbort(dom, path, abort_flags) < 0) {
+ vshError(ctl, _("failed to abort job for disk %s"), path);
+ goto cleanup;
+ }
+ if (abort_flags & VIR_DOMAIN_BLOCK_JOB_ABORT_ASYNC)
+ break;
+ } else {
+ usleep(500 * 1000);
+ }
+ }
+
+ if (verbose && !quit) {
+ /* printf [100 %] */
+ print_job_progress(_("Block Commit"), 0, 1);
+ }
+ vshPrint(ctl, "\n%s", quit ? _("Commit aborted") :
_("Commit complete"));
Meh a ternary ... but saves lines.
+
+ ret = true;
+cleanup:
+ if (dom)
+ virDomainFree(dom);
+ if (blocking)
+ sigaction(SIGINT, &old_sig_action, NULL);
+ return ret;
+}
+
+/*
* "blockcopy" command
*/
static const vshCmdInfo info_block_copy[] = {
@@ -8112,6 +8262,7 @@ const vshCmdDef domManagementCmds[] = {
{"autostart", cmdAutostart, opts_autostart, info_autostart, 0},
{"blkdeviotune", cmdBlkdeviotune, opts_blkdeviotune, info_blkdeviotune,
0},
{"blkiotune", cmdBlkiotune, opts_blkiotune, info_blkiotune, 0},
+ {"blockcommit", cmdBlockCommit, opts_block_commit, info_block_commit, 0},
{"blockcopy", cmdBlockCopy, opts_block_copy, info_block_copy, 0},
{"blockjob", cmdBlockJob, opts_block_job, info_block_job, 0},
{"blockpull", cmdBlockPull, opts_block_pull, info_block_pull, 0},
diff --git a/tools/virsh.pod b/tools/virsh.pod
index bb135da..4a79e12 100644
--- a/tools/virsh.pod
+++ b/tools/virsh.pod
@@ -694,6 +694,36 @@ currently in use by a running domain. Other contexts that require a
MAC
address of virtual interface (such as I<detach-interface> or
I<domif-setlink>) will accept the MAC address printed by this command.
+=item B<blockcommit> I<domain> I<path> [I<bandwidth>]
+{[I<base>] | [I<--shallow>]} [I<top>] [I<--delete>]
+[I<--wait> [I<--verbose>] [I<--timeout> B<seconds>]]
+
+Reduce the length of a backing image chain, by committing changes at the
+top of the chain (snapshot or delta files) into backing images. By
+default, this command attempts to flatten the entire chain. If I<base>
+and/or I<top> are specified as files within the backing chain, then the
+operation is constrained to committing just that portion of the chain;
+I<--shallow> can be used instead of I<base> to specify the immediate
+backing file of the resulting top image to be committed. The files
+being committed are rendered invalid, possibly as soon as the operation
+starts; using the I<--delete> flag will remove these files at the successful
+completion of the commit operation.
+
+By default, this command returns as soon as possible, and data for
+the entire disk is committed in the background; the progress of the
+operation can be checked with B<blockjob>. However, if I<--wait> is
+specified, then this command will block until the operation completes,
+or cancel the operation if the optional I<timeout> in seconds elapses
+or SIGINT is sent (usually with C<Ctrl-C>). Using I<--verbose> along
+with I<--wait> will produce periodic status updates.
+
+I<path> specifies fully-qualified path of the disk; it corresponds
+to a unique target name (<target dev='name'/>) or source file (<source
+file='name'/>) for one of the disk devices attached to I<domain> (see
Okay, this answers my question from the beginning.
+also B<domblklist> for listing these names).
+I<bandwidth> specifies copying bandwidth limit in MiB/s, although for
+qemu, it may be non-zero only for an online domain.
+
=item B<blockcopy> I<domain> I<path> I<dest>
[I<bandwidth>] [I<--shallow>]
[I<--reuse-external>] [I<--raw>] [I<--wait> [I<--verbose]
[{I<--pivot> | I<--finish>}] [I<--timeout> B<seconds>]
[I<--async>]]
Your docs are always great. ACK
Peter