From: Hannes Reinecke <hare@suse.de>
Date: Wed, 5 May 2021 12:15:55 +0000 (+0200)
Subject: tree: add 'nvme_update_config()' as API function
X-Git-Tag: v1.0-rc0~129^2~1
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=ab242a6a4d9f6155eaf1685720f2fdc34b08be5e;p=users%2Fsagi%2Flibnvme.git

tree: add 'nvme_update_config()' as API function

Add a function nvme_update_config() to write out the configuration
as an JSON file.

Signed-off-by: Hannes Reinecke <hare@suse.de>
---

diff --git a/src/nvme/json.c b/src/nvme/json.c
index 98280822..c902a3e9 100644
--- a/src/nvme/json.c
+++ b/src/nvme/json.c
@@ -227,11 +227,12 @@ static void json_update_subsys(struct json_object *subsys_array,
 	json_object_array_add(subsys_array, subsys_obj);
 }
 
-void json_update_config(nvme_root_t r, const char *config_file)
+int json_update_config(nvme_root_t r, const char *config_file)
 {
 	nvme_host_t h;
 	struct json_object *json_root, *host_obj;
 	struct json_object *subsys_array;
+	int ret = 0;
 
 	json_root = json_object_new_array();
 	nvme_for_each_host(r, h) {
@@ -260,6 +261,10 @@ void json_update_config(nvme_root_t r, const char *config_file)
 				    JSON_C_TO_STRING_PRETTY) < 0) {
 		fprintf(stderr, "Failed to write %s, %s\n",
 			config_file, json_util_get_last_err());
+		ret = -1;
+		errno = EIO;
 	}
 	json_object_put(json_root);
+
+	return ret;
 }
diff --git a/src/nvme/private.h b/src/nvme/private.h
index bc823abb..3d1a164f 100644
--- a/src/nvme/private.h
+++ b/src/nvme/private.h
@@ -13,6 +13,6 @@ int nvme_set_attr(const char *dir, const char *attr, const char *value);
 
 void json_read_config(nvme_root_t r, const char *config_file);
 
-void json_update_config(nvme_root_t r, const char *config_file);
+int json_update_config(nvme_root_t r, const char *config_file);
 
 #endif /* _LIBNVME_PRIVATE_H */
diff --git a/src/nvme/tree.c b/src/nvme/tree.c
index 518e89ed..38333e97 100644
--- a/src/nvme/tree.c
+++ b/src/nvme/tree.c
@@ -132,6 +132,7 @@ struct nvme_host {
 
 struct nvme_root {
 	struct list_head hosts;
+	bool modified;
 };
 
 static inline void nvme_free_dirents(struct dirent **d, int i)
@@ -202,6 +203,13 @@ nvme_root_t nvme_scan(const char *config_file)
 	return r;
 }
 
+int nvme_update_config(nvme_root_t r, const char *config_file)
+{
+	if (!r->modified)
+		return 0;
+	return json_update_config(r, config_file);
+}
+
 nvme_host_t nvme_first_host(nvme_root_t r)
 {
 	return list_top(&r->hosts, struct nvme_host, entry);
@@ -360,6 +368,7 @@ struct nvme_subsystem *nvme_lookup_subsystem(struct nvme_host *h,
 	list_head_init(&s->ctrls);
 	list_head_init(&s->namespaces);
 	list_add(&h->subsystems, &s->entry);
+	h->r->modified = true;
 	return s;
 }
 
@@ -373,6 +382,7 @@ static void nvme_free_host(struct nvme_host *h)
 	free(h->hostnqn);
 	if (h->hostid)
 		free(h->hostid);
+	h->r->modified = true;
 	free(h);
 }
 
@@ -399,6 +409,7 @@ struct nvme_host *nvme_lookup_host(nvme_root_t r, const char *hostnqn,
 	list_node_init(&h->entry);
 	h->r = r;
 	list_add(&r->hosts, &h->entry);
+	r->modified = true;
 
 	return h;
 }
@@ -435,7 +446,8 @@ static int nvme_subsystem_scan_ctrls(struct nvme_subsystem *s)
 	return 0;
 }
 
-int nvme_init_subsystem(nvme_subsystem_t s, const char *name, const char *path)
+static int nvme_init_subsystem(nvme_subsystem_t s, const char *name,
+			       const char *path)
 {
 	s->model = nvme_get_attr(path, "model");
 	if (!s->model) {
@@ -693,6 +705,7 @@ struct nvme_fabrics_config *nvme_ctrl_get_config(nvme_ctrl_t c)
 void nvme_ctrl_disable_sqflow(nvme_ctrl_t c, bool disable_sqflow)
 {
 	c->cfg.disable_sqflow = disable_sqflow;
+	c->s->h->r->modified = true;
 }
 
 void nvme_ctrl_set_discovered(nvme_ctrl_t c, bool discovered)
@@ -888,6 +901,7 @@ struct nvme_ctrl *nvme_lookup_ctrl(struct nvme_subsystem *s,
 	if (c) {
 		c->s = s;
 		list_add(&s->ctrls, &c->entry);
+		s->h->r->modified = true;
 	}
 	return c;
 }
diff --git a/src/nvme/tree.h b/src/nvme/tree.h
index 68428e9f..8823254a 100644
--- a/src/nvme/tree.h
+++ b/src/nvme/tree.h
@@ -974,6 +974,15 @@ void nvme_refresh_topology(nvme_root_t r);
  */
 void nvme_reset_topology(nvme_root_t r);
 
+/**
+ * nvme_update_config() -
+ * @r:
+ * @config_file:
+ *
+ * Return:
+ */
+int nvme_update_config(nvme_root_t r, const char *config_file);
+
 /**
  * nvme_free_tree() -
  * @r: