nvme-cli/0007-fabrics-only-look-for-matching-ctrl-on-same-host.patch

From 9cf31d24f8b3911b870cb217c6715637459a376a Mon Sep 17 00:00:00 2001
From: Caleb Sander <csander@purestorage.com>
Date: Wed, 28 Jun 2023 14:35:24 -0600
Subject: [PATCH] fabrics: only look for matching ctrl on same host
Content-type: text/plain

With the lookup_ctrl() check to prevent duplicate connections,
identical connections from different hosts are no longer possible.
Fix lookup_ctrl() to only look for matching controllers
on the same host that is being connected.
This restores the ability for multiple hosts on the same machine
to connect to the same transport addresses on the same subsystem.

Fixes: 07d6b91 ("fabrics: Do not attempt to reconnect to already
connected ctrls")
Signed-off-by: Caleb Sander <csander@purestorage.com>
---
 fabrics.c | 40 ++++++++++++++++++++++++++--------------
 fabrics.h |  2 +-
 nbft.c    |  4 ++--
 3 files changed, 29 insertions(+), 17 deletions(-)

diff --git a/fabrics.c b/fabrics.c
index ac240cad..14a91cc6 100644
--- a/fabrics.c
+++ b/fabrics.c
@@ -149,6 +149,8 @@ static bool is_persistent_discovery_ctrl(nvme_host_t h, nvme_ctrl_t c)
 	return false;
 }
 
+typedef bool (*ctrl_match_fn_t)(nvme_ctrl_t, struct tr_config *);
+
 static bool disc_ctrl_config_match(nvme_ctrl_t c, struct tr_config *trcfg)
 {
 	if (nvme_ctrl_is_discovery_ctrl(c) &&
@@ -175,34 +177,45 @@ static bool ctrl_config_match(nvme_ctrl_t c, struct tr_config *trcfg)
 	return false;
 }
 
-static nvme_ctrl_t __lookup_ctrl(nvme_root_t r, struct tr_config *trcfg,
-			     bool (*filter)(nvme_ctrl_t, struct tr_config *))
+static nvme_ctrl_t __lookup_host_ctrl(nvme_host_t h, struct tr_config *trcfg,
+				      ctrl_match_fn_t filter)
 {
-	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;
+	nvme_for_each_subsystem(h, s) {
+		nvme_subsystem_for_each_ctrl(s, c) {
+			if (filter(c, trcfg))
 				return c;
-			}
 		}
 	}
 
 	return NULL;
 }
 
+static nvme_ctrl_t __lookup_ctrl(nvme_root_t r, struct tr_config *trcfg,
+				 ctrl_match_fn_t filter)
+{
+	nvme_host_t h;
+	nvme_ctrl_t c;
+
+	nvme_for_each_host(r, h) {
+		c = __lookup_host_ctrl(h, trcfg, filter);
+		if (c)
+			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);
 }
 
-nvme_ctrl_t lookup_ctrl(nvme_root_t r, struct tr_config *trcfg)
+nvme_ctrl_t lookup_ctrl(nvme_host_t h, struct tr_config *trcfg)
 {
-	return __lookup_ctrl(r, trcfg, ctrl_config_match);
+	return __lookup_host_ctrl(h, trcfg, ctrl_config_match);
 }
 
 static int set_discovery_kato(struct nvme_fabrics_config *cfg)
@@ -317,7 +330,6 @@ 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 = {
@@ -362,7 +374,7 @@ static int __discover(nvme_ctrl_t c, struct nvme_fabrics_config *defcfg,
 			};
 
 			/* Already connected ? */
-			cl = lookup_ctrl(r, &trcfg);
+			cl = lookup_ctrl(h, &trcfg);
 			if (cl && nvme_ctrl_get_name(cl))
 				continue;
 
@@ -989,7 +1001,7 @@ int nvmf_connect(const char *desc, int argc, char **argv)
 		.trsvcid	= trsvcid,
 	};
 
-	c = lookup_ctrl(r, &trcfg);
+	c = lookup_ctrl(h, &trcfg);
 	if (c && nvme_ctrl_get_name(c)) {
 		fprintf(stderr, "already connected\n");
 		errno = EALREADY;
diff --git a/fabrics.h b/fabrics.h
index 02cebf5d..c16df604 100644
--- a/fabrics.h
+++ b/fabrics.h
@@ -11,7 +11,7 @@ struct tr_config {
 	const char *trsvcid;
 };
 
-extern nvme_ctrl_t lookup_ctrl(nvme_root_t r, struct tr_config *trcfg);
+extern nvme_ctrl_t lookup_ctrl(nvme_host_t h, struct tr_config *trcfg);
 extern int nvmf_discover(const char *desc, int argc, char **argv, bool connect);
 extern int nvmf_connect(const char *desc, int argc, char **argv);
 extern int nvmf_disconnect(const char *desc, int argc, char **argv);
diff --git a/nbft.c b/nbft.c
index c73413f5..e46e9d3d 100644
--- a/nbft.c
+++ b/nbft.c
@@ -144,7 +144,7 @@ int discover_from_nbft(nvme_root_t r, char *hostnqn_arg, char *hostid_arg,
 				};
 
 				/* Already connected ? */
-				cl = lookup_ctrl(r, &trcfg);
+				cl = lookup_ctrl(h, &trcfg);
 				if (cl && nvme_ctrl_get_name(cl))
 					continue;
 
@@ -170,7 +170,7 @@ int discover_from_nbft(nvme_root_t r, char *hostnqn_arg, char *hostid_arg,
 					nvme_free_ctrl(c);
 
 					trcfg.host_traddr = NULL;
-					cl = lookup_ctrl(r, &trcfg);
+					cl = lookup_ctrl(h, &trcfg);
 					if (cl && nvme_ctrl_get_name(cl))
 						continue;
 
-- 
2.39.3