storage: add findPoolSources to iscsi_direct pool backend

Change the SetContext function to be able to take the session type in
argument.
Took the function findPoolSources of iscsi backend and wired it to my
function since the formatting is essentially the same.
Signed-off-by: NClementine Hayat <clem@lse.epita.fr>
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

src/storage/storage_backend_iscsi_direct.c

@@ -131,7 +131,8 @@ virStorageBackendISCSIDirectSetAuth(struct iscsi_context *iscsi,
 
 static int
 virISCSIDirectSetContext(struct iscsi_context *iscsi,
-                         const char *target_name)
+                         const char *target_name,
+                         enum iscsi_session_type session)
 {
     if (iscsi_init_transport(iscsi, TCP_TRANSPORT) < 0) {
         virReportError(VIR_ERR_INTERNAL_ERROR,
@@ -139,13 +140,15 @@ virISCSIDirectSetContext(struct iscsi_context *iscsi,
                        iscsi_get_error(iscsi));
         return -1;
     }
-    if (iscsi_set_targetname(iscsi, target_name) < 0) {
-        virReportError(VIR_ERR_INTERNAL_ERROR,
-                       _("Failed to set target name: %s"),
-                       iscsi_get_error(iscsi));
-        return -1;
+    if (session == ISCSI_SESSION_NORMAL) {
+        if (iscsi_set_targetname(iscsi, target_name) < 0) {
+            virReportError(VIR_ERR_INTERNAL_ERROR,
+                           _("Failed to set target name: %s"),
+                           iscsi_get_error(iscsi));
+            return -1;
+        }
     }
-    if (iscsi_set_session_type(iscsi, ISCSI_SESSION_NORMAL) < 0) {
+    if (iscsi_set_session_type(iscsi, session) < 0) {
         virReportError(VIR_ERR_INTERNAL_ERROR,
                        _("Failed to set session type: %s"),
                        iscsi_get_error(iscsi));
@@ -397,6 +400,73 @@ virISCSIDirectDisconnect(struct iscsi_context *iscsi)
     return 0;
 }
 
+static int
+virISCSIDirectUpdateTargets(struct iscsi_context *iscsi,
+                            size_t *ntargets,
+                            char ***targets)
+{
+    int ret = -1;
+    struct iscsi_discovery_address *addr;
+    struct iscsi_discovery_address *tmp_addr;
+    size_t tmp_ntargets = 0;
+    char **tmp_targets = NULL;
+
+    if (!(addr = iscsi_discovery_sync(iscsi))) {
+        virReportError(VIR_ERR_INTERNAL_ERROR,
+                       _("Failed to discover session: %s"),
+                       iscsi_get_error(iscsi));
+        return ret;
+    }
+
+    for (tmp_addr = addr; tmp_addr; tmp_addr = tmp_addr->next) {
+        char *target = NULL;
+
+        if (VIR_STRDUP(target, tmp_addr->target_name) < 0)
+            goto cleanup;
+
+        if (VIR_APPEND_ELEMENT(tmp_targets, tmp_ntargets, target) < 0) {
+            VIR_FREE(target);
+            goto cleanup;
+        }
+    }
+
+    VIR_STEAL_PTR(*targets, tmp_targets);
+    *ntargets = tmp_ntargets;
+    tmp_ntargets = 0;
+
+    ret = 0;
+ cleanup:
+    iscsi_free_discovery_data(iscsi, addr);
+    virStringListFreeCount(tmp_targets, tmp_ntargets);
+    return ret;
+}
+
+static int
+virISCSIDirectScanTargets(char *initiator_iqn,
+                          char *portal,
+                          size_t *ntargets,
+                          char ***targets)
+{
+    struct iscsi_context *iscsi = NULL;
+    int ret = -1;
+
+    if (!(iscsi = virISCSIDirectCreateContext(initiator_iqn)))
+        goto cleanup;
+    if (virISCSIDirectSetContext(iscsi, NULL, ISCSI_SESSION_DISCOVERY) < 0)
+        goto cleanup;
+    if (virISCSIDirectConnect(iscsi, portal) < 0)
+        goto cleanup;
+    if (virISCSIDirectUpdateTargets(iscsi, ntargets, targets) < 0)
+        goto disconnect;
+
+    ret = 0;
+ disconnect:
+    virISCSIDirectDisconnect(iscsi);
+ cleanup:
+    iscsi_destroy_context(iscsi);
+    return ret;
+}
+
 static int
 virStorageBackendISCSIDirectCheckPool(virStoragePoolObjPtr pool,
                                       bool *isActive)
@@ -405,6 +475,85 @@ virStorageBackendISCSIDirectCheckPool(virStoragePoolObjPtr pool,
     return 0;
 }
 
+static char *
+virStorageBackendISCSIDirectFindPoolSources(const char *srcSpec,
+                                            unsigned int flags)
+{
+    virStoragePoolSourcePtr source = NULL;
+    size_t ntargets = 0;
+    char **targets = NULL;
+    char *ret = NULL;
+    size_t i;
+    virStoragePoolSourceList list = {
+        .type = VIR_STORAGE_POOL_ISCSI_DIRECT,
+        .nsources = 0,
+        .sources = NULL
+    };
+    char *portal = NULL;
+
+    virCheckFlags(0, NULL);
+
+    if (!srcSpec) {
+        virReportError(VIR_ERR_INVALID_ARG, "%s",
+                       _("hostname must be specified for iscsi sources"));
+        return NULL;
+    }
+
+    if (!(source = virStoragePoolDefParseSourceString(srcSpec, list.type)))
+        return NULL;
+
+    if (source->nhost != 1) {
+        virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+                       _("Expected exactly 1 host for the storage pool"));
+        goto cleanup;
+    }
+
+    if (!source->initiator.iqn) {
+        virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+                       _("missing initiator IQN"));
+        goto cleanup;
+    }
+
+    if (!(portal = virStorageBackendISCSIDirectPortal(source)))
+        goto cleanup;
+
+    if (virISCSIDirectScanTargets(source->initiator.iqn, portal, &ntargets, &targets) < 0)
+        goto cleanup;
+
+    if (VIR_ALLOC_N(list.sources, ntargets) < 0)
+        goto cleanup;
+
+    for (i = 0; i < ntargets; i++) {
+        if (VIR_ALLOC_N(list.sources[i].devices, 1) < 0 ||
+            VIR_ALLOC_N(list.sources[i].hosts, 1) < 0)
+            goto cleanup;
+        list.sources[i].nhost = 1;
+        list.sources[i].hosts[0] = source->hosts[0];
+        list.sources[i].initiator = source->initiator;
+        list.sources[i].ndevice = 1;
+        list.sources[i].devices[0].path = targets[i];
+        list.nsources++;
+    }
+
+    if (!(ret = virStoragePoolSourceListFormat(&list)))
+        goto cleanup;
+
+ cleanup:
+    if (list.sources) {
+        for (i = 0; i < ntargets; i++) {
+            VIR_FREE(list.sources[i].hosts);
+            VIR_FREE(list.sources[i].devices);
+        }
+        VIR_FREE(list.sources);
+    }
+    for (i = 0; i < ntargets; i++)
+        VIR_FREE(targets[i]);
+    VIR_FREE(targets);
+    VIR_FREE(portal);
+    virStoragePoolSourceFree(source);
+    return ret;
+}
+
 static int
 virStorageBackendISCSIDirectRefreshPool(virStoragePoolObjPtr pool)
 {
@@ -419,7 +568,7 @@ virStorageBackendISCSIDirectRefreshPool(virStoragePoolObjPtr pool)
         goto cleanup;
     if (virStorageBackendISCSIDirectSetAuth(iscsi, &def->source) < 0)
         goto cleanup;
-    if (virISCSIDirectSetContext(iscsi, def->source.devices[0].path) < 0)
+    if (virISCSIDirectSetContext(iscsi, def->source.devices[0].path, ISCSI_SESSION_NORMAL) < 0)
         goto cleanup;
     if (virISCSIDirectConnect(iscsi, portal) < 0)
         goto cleanup;
@@ -439,6 +588,7 @@ virStorageBackend virStorageBackendISCSIDirect = {
     .type = VIR_STORAGE_POOL_ISCSI_DIRECT,
 
     .checkPool = virStorageBackendISCSIDirectCheckPool,
+    .findPoolSources = virStorageBackendISCSIDirectFindPoolSources,
     .refreshPool = virStorageBackendISCSIDirectRefreshPool,
 };