fabrics: Do not attempt to reconnect to already connected ctrls

Currently, connect-all and connect will blindly try to reconnect to
already connected controllers. Try to lookup the controller in the local
hierarchy. If found just ignore the attempt and fail.

Note, we have to distinguish between normal controllers and discovery
controller when comparing them. The main difference is that we have
ignore the discovery nqn and assume if we find a discovery controller
it's the correct one (persistent). This basically means the well known
discovery nqn matches any found controller.

Signed-off-by: Daniel Wagner <dwagner@suse.de>

diff --git a/fabrics.c b/fabrics.c
index f255e26776d2a4cd206a7c5aae2d784b6868790e..82017e2bdd7dea54a38c417dbf7e7718b6f5ffd4 100644 (file)
--- a/fabrics.c
+++ b/fabrics.c
@@ -124,6 +124,81 @@ static void space_strip_len(int max, char *str)
        }
 }
 
+/*
+ * Compare two C strings and handle NULL pointers gracefully.
+ * If either of the two strings is NULL, return 0
+ * to let caller ignore the compare.
+ */
+static inline int strcmp0(const char *s1, const char *s2)
+{
+       if (!s1 || !s2)
+               return 0;
+       return strcmp(s1, s2);
+}
+
+/*
+ * Compare two C strings and handle NULL pointers gracefully.
+ * If either of the two strings is NULL, return 0
+ * to let caller ignore the compare.
+ */
+static inline int strcasecmp0(const char *s1, const char *s2)
+{
+       if (!s1 || !s2)
+               return 0;
+       return strcasecmp(s1, s2);
+}
+
+static bool disc_ctrl_config_match(nvme_ctrl_t c, struct tr_config *trcfg)
+{
+       if (!strcmp0(nvme_ctrl_get_transport(c), trcfg->transport) &&
+           !strcasecmp0(nvme_ctrl_get_traddr(c), trcfg->traddr) &&
+           !strcmp0(nvme_ctrl_get_trsvcid(c), trcfg->trsvcid) &&
+           !strcmp0(nvme_ctrl_get_host_traddr(c), trcfg->host_traddr) &&
+           !strcmp0(nvme_ctrl_get_host_iface(c), trcfg->host_iface))
+               return true;
+
+       return false;
+}
+
+static bool ctrl_config_match(nvme_ctrl_t c, struct tr_config *trcfg)
+{
+       if (!strcmp0(nvme_ctrl_get_subsysnqn(c), trcfg->subsysnqn) &&
+           disc_ctrl_config_match(c, trcfg))
+               return true;
+
+       return false;
+}
+
+static nvme_ctrl_t __lookup_ctrl(nvme_root_t r, struct tr_config *trcfg,
+                            bool (*filter)(nvme_ctrl_t, struct tr_config *))
+{
+       nvme_host_t h;
+       nvme_subsystem_t s;
+       nvme_ctrl_t c;
+
+       nvme_for_each_host(r, h) {
+               nvme_for_each_subsystem(h, s) {
+                       nvme_subsystem_for_each_ctrl(s, c) {
+                               if (!(filter(c, trcfg)))
+                                       continue;
+                               return c;
+                       }
+               }
+       }
+
+       return NULL;
+}
+
+static nvme_ctrl_t lookup_discovery_ctrl(nvme_root_t r, struct tr_config *trcfg)
+{
+       return __lookup_ctrl(r, trcfg, disc_ctrl_config_match);
+}
+
+static nvme_ctrl_t lookup_ctrl(nvme_root_t r, struct tr_config *trcfg)
+{
+       return __lookup_ctrl(r, trcfg, ctrl_config_match);
+}
+
 static int set_discovery_kato(struct nvme_fabrics_config *cfg)
 {
        int tmo = cfg->keep_alive_tmo;
@@ -356,6 +431,7 @@ static int __discover(nvme_ctrl_t c, struct nvme_fabrics_config *defcfg,
        struct nvmf_discovery_log *log = NULL;
        nvme_subsystem_t s = nvme_ctrl_get_subsystem(c);
        nvme_host_t h = nvme_subsystem_get_host(s);
+       nvme_root_t r = nvme_host_get_root(h);
        uint64_t numrec;
 
        struct nvme_get_discovery_args args = {
@@ -402,6 +478,19 @@ static int __discover(nvme_ctrl_t c, struct nvme_fabrics_config *defcfg,
                        nvme_ctrl_t child;
                        int tmo = defcfg->keep_alive_tmo;
 
+                       struct tr_config trcfg = {
+                               .subsysnqn      = e->subnqn,
+                               .transport      = nvmf_trtype_str(e->trtype),
+                               .traddr         = e->traddr,
+                               .host_traddr    = defcfg->host_traddr,
+                               .host_iface     = defcfg->host_iface,
+                               .trsvcid        = e->trsvcid,
+                       };
+
+                       /* Already connected ? */
+                       if (lookup_ctrl(r, &trcfg))
+                               continue;
+
                        /* Skip connect if the transport types don't match */
                        if (strcmp(nvme_ctrl_get_transport(c), nvmf_trtype_str(e->trtype)))
                                continue;
@@ -440,62 +529,6 @@ static int __discover(nvme_ctrl_t c, struct nvme_fabrics_config *defcfg,
        return 0;
 }
 
-/*
- * Compare two C strings and handle NULL pointers gracefully.
- * If either of the two strings is NULL, return 0
- * to let caller ignore the compare.
- */
-static inline int strcmp0(const char *s1, const char *s2)
-{
-       if (!s1 || !s2)
-               return 0;
-       return strcmp(s1, s2);
-}
-
-/*
- * Compare two C strings and handle NULL pointers gracefully.
- * If either of the two strings is NULL, return 0
- * to let caller ignore the compare.
- */
-static inline int strcasecmp0(const char *s1, const char *s2)
-{
-       if (!s1 || !s2)
-               return 0;
-       return strcasecmp(s1, s2);
-}
-
-static bool ctrl_config_match(nvme_ctrl_t c, struct tr_config *trcfg)
-{
-       if (!strcmp0(nvme_ctrl_get_transport(c), trcfg->transport) &&
-           !strcasecmp0(nvme_ctrl_get_traddr(c), trcfg->traddr) &&
-           !strcmp0(nvme_ctrl_get_trsvcid(c), trcfg->trsvcid) &&
-           !strcmp0(nvme_ctrl_get_host_traddr(c), trcfg->host_traddr) &&
-           !strcmp0(nvme_ctrl_get_host_iface(c), trcfg->host_iface))
-               return true;
-
-       return false;
-}
-
-static nvme_ctrl_t lookup_discover_ctrl(nvme_root_t r, struct tr_config *trcfg)
-{
-       nvme_host_t h;
-       nvme_subsystem_t s;
-       nvme_ctrl_t c;
-
-       nvme_for_each_host(r, h) {
-               nvme_for_each_subsystem(h, s) {
-                       nvme_subsystem_for_each_ctrl(s, c) {
-                               if (!nvme_ctrl_is_discovery_ctrl(c))
-                                       continue;
-                               if (ctrl_config_match(c, trcfg))
-                                       return c;
-                       }
-               }
-       }
-
-       return NULL;
-}
-
 static char *get_default_trsvcid(const char *transport,
                                 bool discovery_ctrl)
 {
@@ -598,7 +631,7 @@ static int discover_from_conf_file(nvme_root_t r, nvme_host_t h,
                };
 
                if (!force) {
-                       c = lookup_discover_ctrl(r, &trcfg);
+                       c = lookup_discovery_ctrl(r, &trcfg);
                        if (c) {
                                __discover(c, &cfg, raw, connect,
                                           true, flags);
@@ -674,7 +707,7 @@ static int discover_from_json_config_file(nvme_root_t r, nvme_host_t h,
                        };
 
                        if (!force) {
-                               cn = lookup_discover_ctrl(r, &trcfg);
+                               cn = lookup_discovery_ctrl(r, &trcfg);
                                if (cn) {
                                        __discover(c, &cfg, raw, connect,
                                                   true, flags);
@@ -842,7 +875,7 @@ int nvmf_discover(const char *desc, int argc, char **argv, bool connect)
                }
        }
        if (!c && !force) {
-               c = lookup_discover_ctrl(r, &trcfg);
+               c = lookup_discovery_ctrl(r, &trcfg);
                if (c)
                        persistent = true;
        }
@@ -970,6 +1003,22 @@ int nvmf_connect(const char *desc, int argc, char **argv)
                nvme_host_set_dhchap_key(h, hostkey);
        if (!trsvcid)
                trsvcid = get_default_trsvcid(transport, false);
+
+       struct tr_config trcfg = {
+               .subsysnqn      = subsysnqn,
+               .transport      = transport,
+               .traddr         = traddr,
+               .host_traddr    = cfg.host_traddr,
+               .host_iface     = cfg.host_iface,
+               .trsvcid        = trsvcid,
+       };
+
+       if (lookup_ctrl(r, &trcfg)) {
+               fprintf(stderr, "already connected\n");
+               errno = EALREADY;
+               goto out_free;
+       }
+
        c = nvme_create_ctrl(r, subsysnqn, transport, traddr,
                             cfg.host_traddr, cfg.host_iface, trsvcid);
        if (!c) {