qemu: Forbid "sgio" support for SCSI generic host device

The kernel didn't support the unprivileged SGIO for SCSI generic
device finally, and since it's unknow whether the way to support
unprivileged SGIO for SCSI generic device will be similar as for
SCSI block device or not, even it's simliar (I.e. via sysfs, for
SCSI block device, it's /sys/dev/block/8\:0/queue/unpriv_sgio,
for example), the file name might be different, So it's better not
guess what it should be like currently.

This patch removes the related code (mainly about the "shareable"
checking on the "sgio" setting, it's not supported at all, why
we leave checking code there? :-), and error out if "sgio" is
specified in the domain config.

src/qemu/qemu_conf.c

@@ -738,12 +738,8 @@ qemuCheckSharedDevice(virHashTablePtr sharedDevices,
                       virDomainDeviceDefPtr dev)
 {
     virDomainDiskDefPtr disk = NULL;
-    virDomainHostdevDefPtr hostdev = NULL;
     char *sysfs_path = NULL;
     char *key = NULL;
-    char *hostdev_name = NULL;
-    char *hostdev_path = NULL;
-    char *device_path = NULL;
     int val;
     int ret = 0;
 
@@ -755,27 +751,11 @@ qemuCheckSharedDevice(virHashTablePtr sharedDevices,
          */
         if (disk->device != VIR_DOMAIN_DISK_DEVICE_LUN)
             return 0;
-
-        device_path = disk->src;
-    } else if (dev->type == VIR_DOMAIN_DEVICE_HOSTDEV) {
-        hostdev = dev->data.hostdev;
-
-        if (!(hostdev_name = virSCSIDeviceGetDevName(NULL,
-                                                     hostdev->source.subsys.u.scsi.adapter,
-                                                     hostdev->source.subsys.u.scsi.bus,
-                                                     hostdev->source.subsys.u.scsi.target,
-                                                     hostdev->source.subsys.u.scsi.unit)))
-            goto cleanup;
-
-        if (virAsprintf(&hostdev_path, "/dev/%s", hostdev_name) < 0)
-            goto cleanup;
-
-        device_path = hostdev_path;
     } else {
         return 0;
     }
 
-    if (!(sysfs_path = virGetUnprivSGIOSysfsPath(device_path, NULL))) {
+    if (!(sysfs_path = virGetUnprivSGIOSysfsPath(disk->src, NULL))) {
         ret = -1;
         goto cleanup;
     }
@@ -786,7 +766,7 @@ qemuCheckSharedDevice(virHashTablePtr sharedDevices,
     if (!virFileExists(sysfs_path))
         goto cleanup;
 
-    if (!(key = qemuGetSharedDeviceKey(device_path))) {
+    if (!(key = qemuGetSharedDeviceKey(disk->src))) {
         ret = -1;
         goto cleanup;
     }
@@ -797,7 +777,7 @@ qemuCheckSharedDevice(virHashTablePtr sharedDevices,
     if (!(virHashLookup(sharedDevices, key)))
         goto cleanup;
 
-    if (virGetDeviceUnprivSGIO(device_path, NULL, &val) < 0) {
+    if (virGetDeviceUnprivSGIO(disk->src, NULL, &val) < 0) {
         ret = -1;
         goto cleanup;
     }
@@ -809,36 +789,25 @@ qemuCheckSharedDevice(virHashTablePtr sharedDevices,
          disk->sgio == VIR_DOMAIN_DEVICE_SGIO_UNFILTERED))
         goto cleanup;
 
-    if (dev->type == VIR_DOMAIN_DEVICE_DISK) {
-        if (disk->type == VIR_DOMAIN_DISK_TYPE_VOLUME) {
-            virReportError(VIR_ERR_OPERATION_INVALID,
-                           _("sgio of shared disk 'pool=%s' 'volume=%s' conflicts "
-                             "with other active domains"),
-                           disk->srcpool->pool,
-                           disk->srcpool->volume);
-        } else {
-            virReportError(VIR_ERR_OPERATION_INVALID,
-                           _("sgio of shared disk '%s' conflicts with other "
-                             "active domains"), disk->src);
-        }
+    if (disk->type == VIR_DOMAIN_DISK_TYPE_VOLUME) {
+        virReportError(VIR_ERR_OPERATION_INVALID,
+                       _("sgio of shared disk 'pool=%s' 'volume=%s' conflicts "
+                         "with other active domains"),
+                       disk->srcpool->pool,
+                       disk->srcpool->volume);
     } else {
         virReportError(VIR_ERR_OPERATION_INVALID,
-                       _("sgio of shared scsi host device '%s-%d-%d-%d' conflicts "
-                          "with other active domains"),
-                       hostdev->source.subsys.u.scsi.adapter,
-                       hostdev->source.subsys.u.scsi.bus,
-                       hostdev->source.subsys.u.scsi.target,
-                       hostdev->source.subsys.u.scsi.unit);
+                       _("sgio of shared disk '%s' conflicts with other "
+                         "active domains"), disk->src);
     }
 
     ret = -1;
 cleanup:
-    VIR_FREE(hostdev_name);
-    VIR_FREE(hostdev_path);
     VIR_FREE(sysfs_path);
     VIR_FREE(key);
     return ret;
 }
+
 bool
 qemuSharedDeviceEntryDomainExists(qemuSharedDeviceEntryPtr entry,
                                   const char *name,
@@ -1109,8 +1078,6 @@ qemuSetUnprivSGIO(virDomainDeviceDefPtr dev)
     virDomainHostdevDefPtr hostdev = NULL;
     char *sysfs_path = NULL;
     char *path = NULL;
-    char *hostdev_name = NULL;
-    char *hostdev_path = NULL;
     int val = -1;
     int ret = 0;
 
@@ -1128,22 +1095,19 @@ qemuSetUnprivSGIO(virDomainDeviceDefPtr dev)
     } else if (dev->type == VIR_DOMAIN_DEVICE_HOSTDEV) {
         hostdev = dev->data.hostdev;
 
-        if (!hostdev->shareable ||
-            !(hostdev->mode == VIR_DOMAIN_HOSTDEV_MODE_SUBSYS &&
-              hostdev->source.subsys.type == VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_SCSI))
-            return 0;
-
-        if (!(hostdev_name = virSCSIDeviceGetDevName(NULL,
-                                                     hostdev->source.subsys.u.scsi.adapter,
-                                                     hostdev->source.subsys.u.scsi.bus,
-                                                     hostdev->source.subsys.u.scsi.target,
-                                                     hostdev->source.subsys.u.scsi.unit)))
-            goto cleanup;
 
-        if (virAsprintf(&hostdev_path, "/dev/%s", hostdev_name) < 0)
+        if (hostdev->mode == VIR_DOMAIN_HOSTDEV_MODE_SUBSYS &&
+            hostdev->source.subsys.type ==
+            VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_SCSI &&
+            hostdev->source.subsys.u.scsi.sgio) {
+            virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                           _("'sgio' is not supported for SCSI "
+                             "generic device yet "));
+            ret = -1;
             goto cleanup;
+        }
 
-        path = hostdev_path;
+        return 0;
     } else {
         return 0;
     }
@@ -1155,12 +1119,7 @@ qemuSetUnprivSGIO(virDomainDeviceDefPtr dev)
     }
 
     /* By default, filter the SG_IO commands, i.e. set unpriv_sgio to 0.  */
-
-    if (dev->type == VIR_DOMAIN_DEVICE_DISK)
-        val = (disk->sgio == VIR_DOMAIN_DEVICE_SGIO_UNFILTERED);
-    else
-        val = (hostdev->source.subsys.u.scsi.sgio ==
-               VIR_DOMAIN_DEVICE_SGIO_UNFILTERED);
+    val = (disk->sgio == VIR_DOMAIN_DEVICE_SGIO_UNFILTERED);
 
     /* Do not do anything if unpriv_sgio is not supported by the kernel and the
      * whitelist is enabled.  But if requesting unfiltered access, always call
@@ -1172,8 +1131,6 @@ qemuSetUnprivSGIO(virDomainDeviceDefPtr dev)
 
 cleanup:
     VIR_FREE(sysfs_path);
-    VIR_FREE(hostdev_name);
-    VIR_FREE(hostdev_path);
     return ret;
 }