virnetdevbandwidth.c: Separate tc filter creation to a function

Not only this simplifies the code a bit, it prepares the
environment for upcoming patches. The new
virNetDevBandwidthManipulateFilter() function is capable of both
removing a filter and adding a new one. At the same time! Yeah,
this is not currently used anywhere but look at the next commit
where you'll see it.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
This commit is contained in:
Michal Privoznik 2015-04-14 13:47:22 +02:00
parent 2397be694d
commit c6f0be2fcf

View File

@ -43,6 +43,108 @@ virNetDevBandwidthFree(virNetDevBandwidthPtr def)
VIR_FREE(def);
}
/**
* virNetDevBandwidthManipulateFilter:
* @ifname: interface to operate on
* @ifmac_ptr: MAC of the interface to create filter over
* @id: filter ID
* @class_id: where to place traffic
* @remove_old: whether to remove the filter
* @create_new: whether to create the filter
*
* TC filters are as crucial for traffic shaping as QDiscs. While
* QDiscs act like black boxes deciding which packets should be
* held up and which should be sent immediately, it's the filter
* that places a packet into the box. So, we may end up
* constructing a set of filters on a single device (e.g. a
* bridge) and filter the traffic into QDiscs based on the
* originating vNET device.
*
* Long story short, @ifname is the interface where the filter
* should be created. The @ifmac_ptr is the MAC address for which
* the filter should be created (usually different to the MAC
* address of @ifname). Then, like everything - even filters have
* an @id which should be unique (per @ifname). And @class_id
* tells into which QDisc should filter place the traffic.
*
* This function can be used for both, removing stale filter
* (@remove_old set to true) and creating new one (@create_new
* set to true). Both at once for the same price!
*
* Returns: 0 on success,
* -1 otherwise (with error reported).
*/
static int ATTRIBUTE_NONNULL(1)
virNetDevBandwidthManipulateFilter(const char *ifname,
const virMacAddr *ifmac_ptr,
unsigned int id,
const char *class_id,
bool remove_old,
bool create_new)
{
int ret = -1;
char *filter_id = NULL;
virCommandPtr cmd = NULL;
unsigned char ifmac[VIR_MAC_BUFLEN];
char *mac[2] = {NULL, NULL};
if (!(remove_old || create_new)) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("filter creation API error"));
goto cleanup;
}
/* u32 filters must have 800:: prefix. Don't ask. */
if (virAsprintf(&filter_id, "800::%u", id) < 0)
goto cleanup;
if (remove_old) {
int cmd_ret = 0;
cmd = virCommandNew(TC);
virCommandAddArgList(cmd, "filter", "del", "dev", ifname,
"prio", "2", "handle", filter_id, "u32", NULL);
if (virCommandRun(cmd, &cmd_ret) < 0)
goto cleanup;
}
if (create_new) {
virMacAddrGetRaw(ifmac_ptr, ifmac);
if (virAsprintf(&mac[0], "0x%02x%02x%02x%02x", ifmac[2],
ifmac[3], ifmac[4], ifmac[5]) < 0 ||
virAsprintf(&mac[1], "0x%02x%02x", ifmac[0], ifmac[1]) < 0)
goto cleanup;
virCommandFree(cmd);
cmd = virCommandNew(TC);
/* Okay, this not nice. But since libvirt does not necessarily track
* interface IP address(es), and tc fw filter simply refuse to use
* ebtables marks, we need to use u32 selector to match MAC address.
* If libvirt will ever know something, remove this FIXME
*/
virCommandAddArgList(cmd, "filter", "add", "dev", ifname, "protocol", "ip",
"prio", "2", "handle", filter_id, "u32",
"match", "u16", "0x0800", "0xffff", "at", "-2",
"match", "u32", mac[0], "0xffffffff", "at", "-12",
"match", "u16", mac[1], "0xffff", "at", "-14",
"flowid", class_id, NULL);
if (virCommandRun(cmd, NULL) < 0)
goto cleanup;
}
ret = 0;
cleanup:
VIR_FREE(mac[1]);
VIR_FREE(mac[0]);
VIR_FREE(filter_id);
virCommandFree(cmd);
return ret;
}
/**
* virNetDevBandwidthSet:
@ -416,19 +518,15 @@ virNetDevBandwidthPlug(const char *brname,
virCommandPtr cmd = NULL;
char *class_id = NULL;
char *qdisc_id = NULL;
char *filter_id = NULL;
char *floor = NULL;
char *ceil = NULL;
unsigned char ifmac[VIR_MAC_BUFLEN];
char ifmacStr[VIR_MAC_STRING_BUFLEN];
char *mac[2] = {NULL, NULL};
if (id <= 2) {
virReportError(VIR_ERR_INTERNAL_ERROR, _("Invalid class ID %d"), id);
return -1;
}
virMacAddrGetRaw(ifmac_ptr, ifmac);
virMacAddrFormat(ifmac_ptr, ifmacStr);
if (!net_bandwidth || !net_bandwidth->in) {
@ -441,10 +539,6 @@ virNetDevBandwidthPlug(const char *brname,
if (virAsprintf(&class_id, "1:%x", id) < 0 ||
virAsprintf(&qdisc_id, "%x:", id) < 0 ||
virAsprintf(&filter_id, "%u", id) < 0 ||
virAsprintf(&mac[0], "0x%02x%02x%02x%02x", ifmac[2],
ifmac[3], ifmac[4], ifmac[5]) < 0 ||
virAsprintf(&mac[1], "0x%02x%02x", ifmac[0], ifmac[1]) < 0 ||
virAsprintf(&floor, "%llukbps", bandwidth->in->floor) < 0 ||
virAsprintf(&ceil, "%llukbps", net_bandwidth->in->peak ?
net_bandwidth->in->peak :
@ -468,31 +562,15 @@ virNetDevBandwidthPlug(const char *brname,
if (virCommandRun(cmd, NULL) < 0)
goto cleanup;
virCommandFree(cmd);
cmd = virCommandNew(TC);
/* Okay, this not nice. But since libvirt does not know anything about
* interface IP address(es), and tc fw filter simply refuse to use ebtables
* marks, we need to use u32 selector to match MAC address.
* If libvirt will ever know something, remove this FIXME
*/
virCommandAddArgList(cmd, "filter", "add", "dev", brname, "protocol", "ip",
"prio", filter_id, "u32",
"match", "u16", "0x0800", "0xffff", "at", "-2",
"match", "u32", mac[0], "0xffffffff", "at", "-12",
"match", "u16", mac[1], "0xffff", "at", "-14",
"flowid", class_id, NULL);
if (virCommandRun(cmd, NULL) < 0)
if (virNetDevBandwidthManipulateFilter(brname, ifmac_ptr, id,
class_id, false, true) < 0)
goto cleanup;
ret = 0;
cleanup:
VIR_FREE(mac[1]);
VIR_FREE(mac[0]);
VIR_FREE(ceil);
VIR_FREE(floor);
VIR_FREE(filter_id);
VIR_FREE(qdisc_id);
VIR_FREE(class_id);
virCommandFree(cmd);
@ -517,7 +595,6 @@ virNetDevBandwidthUnplug(const char *brname,
virCommandPtr cmd = NULL;
char *class_id = NULL;
char *qdisc_id = NULL;
char *filter_id = NULL;
if (id <= 2) {
virReportError(VIR_ERR_INTERNAL_ERROR, _("Invalid class ID %d"), id);
@ -525,8 +602,7 @@ virNetDevBandwidthUnplug(const char *brname,
}
if (virAsprintf(&class_id, "1:%x", id) < 0 ||
virAsprintf(&qdisc_id, "%x:", id) < 0 ||
virAsprintf(&filter_id, "%u", id) < 0)
virAsprintf(&qdisc_id, "%x:", id) < 0)
goto cleanup;
cmd = virCommandNew(TC);
@ -538,12 +614,8 @@ virNetDevBandwidthUnplug(const char *brname,
if (virCommandRun(cmd, &cmd_ret) < 0)
goto cleanup;
virCommandFree(cmd);
cmd = virCommandNew(TC);
virCommandAddArgList(cmd, "filter", "del", "dev", brname,
"prio", filter_id, NULL);
if (virCommandRun(cmd, &cmd_ret) < 0)
if (virNetDevBandwidthManipulateFilter(brname, NULL, id,
NULL, true, false) < 0)
goto cleanup;
virCommandFree(cmd);
@ -557,7 +629,6 @@ virNetDevBandwidthUnplug(const char *brname,
ret = 0;
cleanup:
VIR_FREE(filter_id);
VIR_FREE(qdisc_id);
VIR_FREE(class_id);
virCommandFree(cmd);