qemu: Add optional unit to qemuMigrationParamsTPMapItem

Some migration parameters supported by libvirt may use units that differ
from the units used by QEMU for the corresponding parameters. For
example, libvirt defines migration bandwidth in MiB/s while QEMU expects
B/s. Let's add a unit field to qemuMigrationParamsTPMapItem for
automatic conversion when translating between libvirt's migration typed
parameters and QEMU's migration paramteres.

This patch is a preparation for future parameters as the existing
VIR_MIGRATE_PARAM_BANDWIDTH parameter is set using "migrate_set_speed"
QMP command rather than "migrate-set-parameters" for backward
compatibility.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>

src/qemu/qemu_migration_params.c

@@ -120,6 +120,7 @@ struct _qemuMigrationParamsFlagMapItem {
 typedef struct _qemuMigrationParamsTPMapItem qemuMigrationParamsTPMapItem;
 struct _qemuMigrationParamsTPMapItem {
     const char *typedParam;
+    unsigned int unit;
     qemuMigrationParam param;
     int party; /* bit-wise OR of qemuMigrationParty */
 };
@@ -273,7 +274,8 @@ qemuMigrationParamsGetTPInt(qemuMigrationParamsPtr migParams,
                             qemuMigrationParam param,
                             virTypedParameterPtr params,
                             int nparams,
-                            const char *name)
+                            const char *name,
+                            unsigned int unit)
 {
     int rc;
 
@@ -287,6 +289,17 @@ qemuMigrationParamsGetTPInt(qemuMigrationParamsPtr migParams,
                                    &migParams->params[param].value.i)) < 0)
         return -1;
 
+    if (unit > 0) {
+        unsigned int max = UINT_MAX / unit;
+        if (migParams->params[param].value.i > max) {
+            virReportError(VIR_ERR_OVERFLOW,
+                           _("migration parameter '%s' must be less than %u"),
+                           name, max + 1);
+            return -1;
+        }
+        migParams->params[param].value.i *= unit;
+    }
+
     migParams->params[param].set = !!rc;
     return 0;
 }
@@ -298,16 +311,22 @@ qemuMigrationParamsSetTPInt(qemuMigrationParamsPtr migParams,
                             virTypedParameterPtr *params,
                             int *nparams,
                             int *maxparams,
-                            const char *name)
+                            const char *name,
+                            unsigned int unit)
 {
+    int value;
+
     if (qemuMigrationParamsCheckType(param, QEMU_MIGRATION_PARAM_TYPE_INT) < 0)
         return -1;
 
     if (!migParams->params[param].set)
         return 0;
 
-    return virTypedParamsAddInt(params, nparams, maxparams, name,
+    value = migParams->params[param].value.i;
-                                migParams->params[param].value.i);
+    if (unit > 0)
+        value /= unit;
+
+    return virTypedParamsAddInt(params, nparams, maxparams, name, value);
 }
 
 
@@ -316,7 +335,8 @@ qemuMigrationParamsGetTPULL(qemuMigrationParamsPtr migParams,
                             qemuMigrationParam param,
                             virTypedParameterPtr params,
                             int nparams,
-                            const char *name)
+                            const char *name,
+                            unsigned int unit)
 {
     int rc;
 
@@ -330,6 +350,17 @@ qemuMigrationParamsGetTPULL(qemuMigrationParamsPtr migParams,
                                       &migParams->params[param].value.ull)) < 0)
         return -1;
 
+    if (unit > 0) {
+        unsigned long long max = ULLONG_MAX / unit;
+        if (migParams->params[param].value.ull > max) {
+            virReportError(VIR_ERR_OVERFLOW,
+                           _("migration parameter '%s' must be less than %llu"),
+                           name, max + 1);
+            return -1;
+        }
+        migParams->params[param].value.ull *= unit;
+    }
+
     migParams->params[param].set = !!rc;
     return 0;
 }
@@ -341,16 +372,22 @@ qemuMigrationParamsSetTPULL(qemuMigrationParamsPtr migParams,
                             virTypedParameterPtr *params,
                             int *nparams,
                             int *maxparams,
-                            const char *name)
+                            const char *name,
+                            unsigned int unit)
 {
+    unsigned long long value;
+
     if (qemuMigrationParamsCheckType(param, QEMU_MIGRATION_PARAM_TYPE_ULL) < 0)
         return -1;
 
     if (!migParams->params[param].set)
         return 0;
 
-    return virTypedParamsAddULLong(params, nparams, maxparams, name,
+    value = migParams->params[param].value.ull;
-                                   migParams->params[param].value.ull);
+    if (unit > 0)
+        value /= unit;
+
+    return virTypedParamsAddULLong(params, nparams, maxparams, name, value);
 }
 
 
@@ -465,13 +502,15 @@ qemuMigrationParamsFromFlags(virTypedParameterPtr params,
         switch (qemuMigrationParamTypes[item->param]) {
         case QEMU_MIGRATION_PARAM_TYPE_INT:
             if (qemuMigrationParamsGetTPInt(migParams, item->param, params,
-                                            nparams, item->typedParam) < 0)
+                                            nparams, item->typedParam,
+                                            item->unit) < 0)
                 goto error;
             break;
 
         case QEMU_MIGRATION_PARAM_TYPE_ULL:
             if (qemuMigrationParamsGetTPULL(migParams, item->param, params,
-                                            nparams, item->typedParam) < 0)
+                                            nparams, item->typedParam,
+                                            item->unit) < 0)
                 goto error;
             break;
 
@@ -533,14 +572,14 @@ qemuMigrationParamsDump(qemuMigrationParamsPtr migParams,
         case QEMU_MIGRATION_PARAM_TYPE_INT:
             if (qemuMigrationParamsSetTPInt(migParams, item->param,
                                             params, nparams, maxparams,
-                                            item->typedParam) < 0)
+                                            item->typedParam, item->unit) < 0)
                 return -1;
             break;
 
         case QEMU_MIGRATION_PARAM_TYPE_ULL:
             if (qemuMigrationParamsSetTPULL(migParams, item->param,
                                             params, nparams, maxparams,
-                                            item->typedParam) < 0)
+                                            item->typedParam, item->unit) < 0)
                 return -1;
             break;