[lustre-devel] [PATCH 02/27] lnet: rework module loading

[James Simmons]

The kernel IS_MODULE() only works in the positive, ie no ifndef.
So rework the LND module loading code to handle if modules are
enabled and use the proper macro. Also don't use request_module
in obdclass module as well unless IS_MODULE is true for Lustre.

WC-bug-id: https://jira.whamcloud.com/browse/LU-12511
Lustre-commit: 6e76d3569bf602d71 ("LU-12511 lnet: rework lnd module loading")
Signed-off-by: James Simmons <jsimmons at infradead.org>
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/57946
Reviewed-by: Frank Sehr <fsehr at whamcloud.com>
Reviewed-by: Serguei Smirnov <ssmirnov at whamcloud.com>
Reviewed-by: Chris Horn <chris.horn at hpe.com>
Reviewed-by: Oleg Drokin <green at whamcloud.com>
---
 fs/lustre/obdclass/genops.c |  4 +++-
 net/lnet/lnet/api-ni.c      | 12 ++++++------
 2 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/fs/lustre/obdclass/genops.c b/fs/lustre/obdclass/genops.c
index a3f7b59db47f..0cbc2c7c393d 100644
--- a/fs/lustre/obdclass/genops.c
+++ b/fs/lustre/obdclass/genops.c
@@ -36,6 +36,7 @@
  */
 
 #define DEBUG_SUBSYSTEM S_CLASS
+#include <linux/kconfig.h>
 #include <linux/libcfs/libcfs_cpu.h>
 #include <obd_class.h>
 #include <lustre_log.h>
@@ -97,7 +98,7 @@ static struct obd_type *class_get_type(const char *name)
 
 	rcu_read_lock();
 	type = class_search_type(name);
-
+#if IS_MODULE(CONFIG_LUSTRE_FS)
 	if (!type) {
 		const char *modname = name;
 
@@ -111,6 +112,7 @@ static struct obd_type *class_get_type(const char *name)
 		rcu_read_lock();
 		type = class_search_type(name);
 	}
+#endif
 	if (type) {
 		/*
 		 * Holding rcu_read_lock() matches the synchronize_rcu() call
diff --git a/net/lnet/lnet/api-ni.c b/net/lnet/lnet/api-ni.c
index 870ae4312d78..d65ccb4e78aa 100644
--- a/net/lnet/lnet/api-ni.c
+++ b/net/lnet/lnet/api-ni.c
@@ -2556,22 +2556,22 @@ static struct lnet_lnd *lnet_load_lnd(u32 lnd_type)
 	mutex_lock(&the_lnet.ln_lnd_mutex);
 	lnd = lnet_find_lnd_by_type(lnd_type);
 	if (!lnd) {
+#if IS_MODULE(CONFIG_LNET)
 		mutex_unlock(&the_lnet.ln_lnd_mutex);
 		rc = request_module("%s", libcfs_lnd2modname(lnd_type));
 		mutex_lock(&the_lnet.ln_lnd_mutex);
 
 		lnd = lnet_find_lnd_by_type(lnd_type);
 		if (!lnd) {
-			mutex_unlock(&the_lnet.ln_lnd_mutex);
 			CERROR("Can't load LND %s, module %s, rc=%d\n",
 			       libcfs_lnd2str(lnd_type),
 			       libcfs_lnd2modname(lnd_type), rc);
-#ifndef HAVE_MODULE_LOADING_SUPPORT
-			LCONSOLE_ERROR_MSG(0x104,
-					   "Your kernel must be compiled with kernel module loading support.");
-#endif
-			return ERR_PTR(-EINVAL);
+			lnd = ERR_PTR(-EINVAL);
 		}
+#else
+		LCONSOLE_ERROR("Could not find LND %s\n", libcfs_lnd2str(lnd_type));
+		lnd = ERR_PTR(-EINVAL);
+#endif
 	}
 	mutex_unlock(&the_lnet.ln_lnd_mutex);
 
-- 
2.39.3