xenconfig: support vif bandwidth in sexpr parser and formatter

The xen sexpr config format has long supported specifying vif rate
limiting, e.g.

  (device
    (vif
      (mac '00:16:3e:1b:b1:47')
      (rate '10240KB/s')
      ...
    )
  )

Add support for mapping rate to and from <bandwidth> in the xenconfig
sexpr parser and formatter. rate is mapped to the required 'average'
attribute of the <outbound> element, e.g.

  <interface type='bridge'>
    ...
    <bandwidth>
      <outbound average='10240'/>
    </bandwidth>
  </interface>

Also add unit tests to check the conversion logic.

This patch benefits both the old xen driver and the libxl driver.
Both drivers gain support for vif bandwidth when converting to/from
domXML and xen-sxpr. In addition, the old xen driver will now be
able to handle vif 'rate' setting when communicating with xend.

src/libvirt_xenconfig.syms

@@ -15,6 +15,7 @@ xenParseSxpr;
 xenParseSxprChar;
 xenParseSxprSound;
 xenParseSxprString;
+xenParseSxprVifRate;
 
 # xenconfig/xen_xm.h
 xenFormatXM;

src/xenconfig/xen_sxpr.c

@@ -26,6 +26,8 @@
 
 #include <config.h>
 
+#include <regex.h>
+
 #include "internal.h"
 #include "virerror.h"
 #include "virconf.h"
@@ -315,6 +317,56 @@ xenParseSxprChar(const char *value,
 }
 
 
+static const char *vif_bytes_per_sec_re = "^[0-9]+[GMK]?[Bb]/s$";
+
+int
+xenParseSxprVifRate(const char *rate, unsigned long long *kbytes_per_sec)
+{
+    char *trate = NULL;
+    char *p;
+    regex_t rec;
+    char *suffix;
+    unsigned long long tmp;
+    int ret = -1;
+
+    if (VIR_STRDUP(trate, rate) < 0)
+        return -1;
+
+    p = strchr(trate, '@');
+    if (p != NULL)
+        *p = 0;
+
+    regcomp(&rec, vif_bytes_per_sec_re, REG_EXTENDED|REG_NOSUB);
+    if (regexec(&rec, trate, 0, NULL, 0)) {
+        virReportError(VIR_ERR_INTERNAL_ERROR,
+                       _("Invalid rate '%s' specified"), rate);
+        goto cleanup;
+    }
+
+    if (virStrToLong_ull(rate, &suffix, 10, &tmp)) {
+        virReportError(VIR_ERR_INTERNAL_ERROR,
+                       _("Failed to parse rate '%s'"), rate);
+        goto cleanup;
+    }
+
+    if (*suffix == 'G')
+       tmp *= 1024 * 1024;
+    else if (*suffix == 'M')
+       tmp *= 1024;
+
+    if (*suffix == 'b' || *(suffix + 1) == 'b')
+       tmp /= 8;
+
+    *kbytes_per_sec = tmp;
+    ret = 0;
+
+ cleanup:
+    regfree(&rec);
+    VIR_FREE(trate);
+    return ret;
+}
+
+
 /**
  * xenParseSxprDisks:
  * @def: the domain config
@@ -594,6 +646,25 @@ xenParseSxprNets(virDomainDefPtr def,
                 VIR_STRDUP(net->model, "netfront") < 0)
                 goto cleanup;
 
+            tmp = sexpr_node(node, "device/vif/rate");
+            if (tmp) {
+                virNetDevBandwidthPtr bandwidth;
+                unsigned long long kbytes_per_sec;
+
+                if (xenParseSxprVifRate(tmp, &kbytes_per_sec) < 0)
+                    goto cleanup;
+
+                if (VIR_ALLOC(bandwidth) < 0)
+                    goto cleanup;
+                if (VIR_ALLOC(bandwidth->out) < 0) {
+                    VIR_FREE(bandwidth);
+                    goto cleanup;
+                }
+
+                bandwidth->out->average = kbytes_per_sec;
+                net->bandwidth = bandwidth;
+            }
+
             if (VIR_APPEND_ELEMENT(def->nets, def->nnets, net) < 0)
                 goto cleanup;
 
@@ -1783,6 +1854,9 @@ xenFormatSxprNet(virConnectPtr conn,
 
     virBufferAsprintf(buf, "(mac '%s')", virMacAddrFormat(&def->mac, macaddr));
 
+    if (def->bandwidth && def->bandwidth->out && def->bandwidth->out->average)
+        virBufferAsprintf(buf, "(rate '%lluKB/s')", def->bandwidth->out->average);
+
     switch (def->type) {
     case VIR_DOMAIN_NET_TYPE_BRIDGE:
         virBufferEscapeSexpr(buf, "(bridge '%s')", def->data.bridge.brname);

src/xenconfig/xen_sxpr.h

@@ -53,6 +53,8 @@ int xenParseSxprSound(virDomainDefPtr def, const char *str);
 
 virDomainChrDefPtr xenParseSxprChar(const char *value, const char *tty);
 
+int xenParseSxprVifRate(const char *rate, unsigned long long *kbytes_per_sec);
+
 int xenFormatSxprDisk(virDomainDiskDefPtr def, virBufferPtr buf, int hvm,
                       int isAttach);
 

tests/sexpr2xmldata/sexpr2xml-vif-rate.sexpr

@@ -0,0 +1,11 @@
+(domain (domid 3)(name 'fvtest')(memory 400)(maxmem 400)(vcpus 1)\
+(uuid 'b5d70dd275cdaca517769660b059d8bc')(on_poweroff 'destroy')\
+(on_reboot 'restart')(on_crash 'restart')\
+(image (hvm (kernel '/usr/lib/xen/boot/hvmloader')\
+(device_model '/usr/lib64/xen/bin/qemu-dm')(boot c)\
+(acpi 1)(vnc 1)(keymap ja)))(device (vbd (dev 'ioemu:hda')\
+(uname 'file:/root/foo.img')(mode 'w')))\
+(device (vbd (dev 'hdc:cdrom')\
+(uname 'file:/root/boot.iso')(mode 'r')))\
+(device (vif (mac '00:16:3e:1b:b1:47')(bridge 'xenbr0')\
+(script 'vif-bridge')(type 'netfront')(rate '10240KB/s'))))

tests/sexpr2xmldata/sexpr2xml-vif-rate.xml

@@ -0,0 +1,51 @@
+<domain type='xen' id='3'>
+  <name>fvtest</name>
+  <uuid>b5d70dd2-75cd-aca5-1776-9660b059d8bc</uuid>
+  <memory unit='KiB'>409600</memory>
+  <currentMemory unit='KiB'>409600</currentMemory>
+  <vcpu placement='static'>1</vcpu>
+  <os>
+    <type>hvm</type>
+    <loader type='rom'>/usr/lib/xen/boot/hvmloader</loader>
+    <boot dev='hd'/>
+  </os>
+  <features>
+    <acpi/>
+  </features>
+  <clock offset='variable' adjustment='0' basis='utc'/>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>restart</on_reboot>
+  <on_crash>restart</on_crash>
+  <devices>
+    <emulator>/usr/lib64/xen/bin/qemu-dm</emulator>
+    <disk type='file' device='disk'>
+      <driver name='file'/>
+      <source file='/root/foo.img'/>
+      <backingStore/>
+      <target dev='hda' bus='ide'/>
+      <address type='drive' controller='0' bus='0' target='0' unit='0'/>
+    </disk>
+    <disk type='file' device='cdrom'>
+      <driver name='file'/>
+      <source file='/root/boot.iso'/>
+      <backingStore/>
+      <target dev='hdc' bus='ide'/>
+      <readonly/>
+      <address type='drive' controller='0' bus='1' target='0' unit='0'/>
+    </disk>
+    <interface type='bridge'>
+      <mac address='00:16:3e:1b:b1:47'/>
+      <source bridge='xenbr0'/>
+      <bandwidth>
+        <outbound average='10240'/>
+      </bandwidth>
+      <script path='vif-bridge'/>
+      <target dev='vif3.0'/>
+      <model type='netfront'/>
+    </interface>
+    <input type='mouse' bus='ps2'/>
+    <input type='keyboard' bus='ps2'/>
+    <graphics type='vnc' port='-1' autoport='yes' keymap='ja'/>
+    <memballoon model='xen'/>
+  </devices>
+</domain>

tests/sexpr2xmltest.c

@@ -188,6 +188,8 @@ mymain(void)
 
     DO_TEST("boot-grub", "boot-grub");
 
+    DO_TEST("vif-rate", "vif-rate");
+
     virObjectUnref(caps);
     virObjectUnref(xmlopt);
 

tests/xml2sexprdata/xml2sexpr-fv-net-rate.sexpr

@@ -0,0 +1,10 @@
+(vm (name 'fvtest')(memory 400)(maxmem 400)(vcpus 1)\
+(uuid 'b5d70dd2-75cd-aca5-1776-9660b059d8bc')(on_poweroff 'destroy')\
+(on_reboot 'restart')(on_crash 'restart')\
+(image (hvm (kernel '/usr/lib/xen/boot/hvmloader')(vcpus 1)(boot c)(acpi 1)\
+(usb 1)(parallel none)(serial none)(device_model '/usr/lib64/xen/bin/qemu-dm')\
+(vnc 1)(vncunused 0)(vncdisplay 17)(keymap 'ja')(rtc_timeoffset 0)(localtime 0)))\
+(localtime 0)\
+(device (vbd (dev 'hda:disk')(uname 'file:/root/foo.img')\
+(mode 'w')))(device (vif (mac '00:16:3e:1b:b1:47')(rate '10240KB/s')\
+(bridge 'xenbr0')(script 'vif-bridge')(type netfront))))

tests/xml2sexprdata/xml2sexpr-fv-net-rate.xml

@@ -0,0 +1,34 @@
+<domain type='xen'>
+  <name>fvtest</name>
+  <uuid>b5d70dd275cdaca517769660b059d8bc</uuid>
+  <os>
+    <type>hvm</type>
+    <loader>/usr/lib/xen/boot/hvmloader</loader>
+    <boot dev='hd'/>
+  </os>
+  <memory unit='KiB'>409600</memory>
+  <vcpu>1</vcpu>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>restart</on_reboot>
+  <on_crash>restart</on_crash>
+  <features>
+    <acpi/>
+  </features>
+  <devices>
+    <emulator>/usr/lib64/xen/bin/qemu-dm</emulator>
+    <interface type='bridge'>
+      <source bridge='xenbr0'/>
+      <bandwidth>
+        <outbound average='10240'/>
+      </bandwidth>
+      <mac address='00:16:3e:1b:b1:47'/>
+      <script path='vif-bridge'/>
+      <model type='netfront'/>
+    </interface>
+    <disk type='file'>
+      <source file='/root/foo.img'/>
+      <target dev='ioemu:hda'/>
+    </disk>
+    <graphics type='vnc' port='5917' keymap='ja'/>
+  </devices>
+</domain>

tests/xml2sexprtest.c

@@ -156,6 +156,7 @@ mymain(void)
     DO_TEST("fv-sound", "fv-sound", "fvtest");
 
     DO_TEST("fv-net-netfront", "fv-net-netfront", "fvtest");
+    DO_TEST("fv-net-rate", "fv-net-rate", "fvtest");
 
     DO_TEST("boot-grub", "boot-grub", "fvtest");
     DO_TEST("escape", "escape", "fvtest");