[libvirt] [PATCH 14/8] save: add --direct flag to virsh restore operations

* tools/virsh.c (cmdStart, cmdRestore): Add new flag. * tools/virsh.pod (start, restore): Document flags. --- Counterpart to 4/8 tools/virsh.c | 9 ++++++++- tools/virsh.pod | 10 ++++++++-- 2 files changed, 16 insertions(+), 3 deletions(-) diff --git a/tools/virsh.c b/tools/virsh.c index 3cf0618..00ea533 100644 --- a/tools/virsh.c +++ b/tools/virsh.c @@ -1481,6 +1481,7 @@ static const vshCmdOptDef opts_start[] = { #endif {"paused", VSH_OT_BOOL, 0, N_("leave the guest paused after creation")}, {"autodestroy", VSH_OT_BOOL, 0, N_("automatically destroy the guest when virsh disconnects")}, + {"direct", VSH_OT_BOOL, 0, N_("use O_DIRECT when loading")}, {NULL, 0, 0, NULL} }; @@ -1511,6 +1512,8 @@ cmdStart(vshControl *ctl, const vshCmd *cmd) flags |= VIR_DOMAIN_START_PAUSED; if (vshCommandOptBool(cmd, "autodestroy")) flags |= VIR_DOMAIN_START_AUTODESTROY; + if (vshCommandOptBool(cmd, "direct")) + flags |= VIR_DOMAIN_START_DIRECT; /* Prefer older API unless we have to pass a flag. */ if ((flags ? virDomainCreateWithFlags(dom, flags) @@ -1940,6 +1943,7 @@ static const vshCmdInfo info_restore[] = { static const vshCmdOptDef opts_restore[] = { {"file", VSH_OT_DATA, VSH_OFLAG_REQ, N_("the state to restore")}, + {"direct", VSH_OT_BOOL, 0, N_("use O_DIRECT when restoring")}, {NULL, 0, 0, NULL} }; @@ -1948,6 +1952,7 @@ cmdRestore(vshControl *ctl, const vshCmd *cmd) { const char *from = NULL; bool ret = true; + bool direct = vshCommandOptBool(cmd, "direct"); if (!vshConnectionUsability(ctl, ctl->conn)) return false; @@ -1955,7 +1960,9 @@ cmdRestore(vshControl *ctl, const vshCmd *cmd) if (vshCommandOptString(cmd, "file", &from) <= 0) return false; - if (virDomainRestore(ctl->conn, from) == 0) { + if ((direct ? virDomainRestoreFlags(ctl->conn, from, NULL, + VIR_DOMAIN_SAVE_DIRECT) + : virDomainRestore(ctl->conn, from)) == 0) { vshPrint(ctl, _("Domain restored from %s\n"), from); } else { vshError(ctl, _("Failed to restore domain from %s"), from); diff --git a/tools/virsh.pod b/tools/virsh.pod index 1e04464..8e8e9bc 100644 --- a/tools/virsh.pod +++ b/tools/virsh.pod @@ -592,10 +592,13 @@ domain actually reboots. The exact behavior of a domain when it reboots is set by the I<on_reboot> parameter in the domain's XML definition. -=item B<restore> I<state-file> +=item B<restore> I<state-file> [I<--direct>] Restores a domain from a B<virsh save> state file. See I<save> for more info. +If I<--direct> is specified, the restore uses O_DIRECT, which reduces +file system cache pressure but may slow down the operation. + B<Note>: To avoid corrupting file system contents within the domain, you should not reuse the saved state file for a second B<restore> unless you have also reverted all storage volumes back to the same contents as when @@ -794,6 +797,7 @@ The exact behavior of a domain when it shuts down is set by the I<on_shutdown> parameter in the domain's XML definition. =item B<start> I<domain-name> [I<--console>] [I<--paused>] [I<--autodestroy>] +[I<--direct>] Start a (previously defined) inactive domain, either from the last B<managedsave> state, or via a fresh boot if no managedsave state is @@ -802,7 +806,9 @@ used and supported by the driver; otherwise it will be running. If I<--console> is requested, attach to the console after creation. If I<--autodestroy> is requested, then the guest will be automatically destroyed when virsh closes its connection to libvirt, or otherwise -exits. +exits. If I<--direct> is specified, and managedsave state exists, +the restore uses O_DIRECT, which reduces file system cache pressure +but may slow down the operation. =item B<suspend> I<domain-id> -- 1.7.4.4