1 files changed, 25 insertions, 115 deletions

diff --git a/fs/cifs/dfs_cache.c b/fs/cifs/dfs_cache.c
index bef672534397..95cc3951420e 100644
--- a/fs/cifs/dfs_cache.c
+++ b/fs/cifs/dfs_cache.c
@@ -83,27 +83,6 @@ static void refresh_cache_worker(struct work_struct *work);
 
 static DECLARE_DELAYED_WORK(refresh_task, refresh_cache_worker);
 
-static void get_ipc_unc(const char *ref_path, char *ipc, size_t ipclen)
-{
-	const char *host;
-	size_t len;
-
-	extract_unc_hostname(ref_path, &host, &len);
-	scnprintf(ipc, ipclen, "\\\\%.*s\\IPC$", (int)len, host);
-}
-
-static struct cifs_ses *find_ipc_from_server_path(struct cifs_ses **ses, const char *path)
-{
-	char unc[SERVER_NAME_LENGTH + sizeof("//x/IPC$")] = {0};
-
-	get_ipc_unc(path, unc, sizeof(unc));
-	for (; *ses; ses++) {
-		if (!strcasecmp(unc, (*ses)->tcon_ipc->tree_name))
-			return *ses;
-	}
-	return ERR_PTR(-ENOENT);
-}
-
 static void __mount_group_release(struct mount_group *mg)
 {
 	int i;
@@ -760,8 +739,6 @@ static int get_dfs_referral(const unsigned int xid, struct cifs_ses *ses, const
 	int rc;
 	int i;
 
-	cifs_dbg(FYI, "%s: get an DFS referral for %s\n", __func__, path);
-
 	*refs = NULL;
 	*numrefs = 0;
 
@@ -770,6 +747,7 @@ static int get_dfs_referral(const unsigned int xid, struct cifs_ses *ses, const
 	if (unlikely(!cache_cp))
 		return -EINVAL;
 
+	cifs_dbg(FYI, "%s: ipc=%s referral=%s\n", __func__, ses->tcon_ipc->tree_name, path);
 	rc =  ses->server->ops->get_dfs_refer(xid, ses, path, refs, numrefs, cache_cp,
 					      NO_MAP_UNI_RSVD);
 	if (!rc) {
@@ -1366,10 +1344,9 @@ static void mark_for_reconnect_if_needed(struct cifs_tcon *tcon, struct dfs_cach
 }
 
 /* Refresh dfs referral of tcon and mark it for reconnect if needed */
-static int __refresh_tcon(const char *path, struct cifs_ses **sessions, struct cifs_tcon *tcon,
-			  bool force_refresh)
+static int __refresh_tcon(const char *path, struct cifs_tcon *tcon, bool force_refresh)
 {
-	struct cifs_ses *ses;
+	struct cifs_ses *ses = CIFS_DFS_ROOT_SES(tcon->ses);
 	struct cache_entry *ce;
 	struct dfs_info3_param *refs = NULL;
 	int numrefs = 0;
@@ -1378,11 +1355,7 @@ static int __refresh_tcon(const char *path, struct cifs_ses **sessions, struct c
 	int rc = 0;
 	unsigned int xid;
 
-	ses = find_ipc_from_server_path(sessions, path);
-	if (IS_ERR(ses)) {
-		cifs_dbg(FYI, "%s: could not find ipc session\n", __func__);
-		return PTR_ERR(ses);
-	}
+	xid = get_xid();
 
 	down_read(&htable_rw_lock);
 	ce = lookup_cache_entry(path);
@@ -1399,12 +1372,9 @@ static int __refresh_tcon(const char *path, struct cifs_ses **sessions, struct c
 		goto out;
 	}
 
-	xid = get_xid();
 	rc = get_dfs_referral(xid, ses, path, &refs, &numrefs);
-	free_xid(xid);
-
-	/* Create or update a cache entry with the new referral */
 	if (!rc) {
+		/* Create or update a cache entry with the new referral */
 		dump_refs(refs, numrefs);
 
 		down_write(&htable_rw_lock);
@@ -1419,24 +1389,20 @@ static int __refresh_tcon(const char *path, struct cifs_ses **sessions, struct c
 	}
 
 out:
+	free_xid(xid);
 	dfs_cache_free_tgts(&tl);
 	free_dfs_info_array(refs, numrefs);
 	return rc;
 }
 
-static int refresh_tcon(struct cifs_ses **sessions, struct cifs_tcon *tcon, bool force_refresh)
+static int refresh_tcon(struct cifs_tcon *tcon, bool force_refresh)
 {
 	struct TCP_Server_Info *server = tcon->ses->server;
 
 	mutex_lock(&server->refpath_lock);
-	if (server->origin_fullpath) {
-		if (server->leaf_fullpath && strcasecmp(server->leaf_fullpath,
-							server->origin_fullpath))
-			__refresh_tcon(server->leaf_fullpath + 1, sessions, tcon, force_refresh);
-		__refresh_tcon(server->origin_fullpath + 1, sessions, tcon, force_refresh);
-	}
+	if (server->leaf_fullpath)
+		__refresh_tcon(server->leaf_fullpath + 1, tcon, force_refresh);
 	mutex_unlock(&server->refpath_lock);
-
 	return 0;
 }
 
@@ -1454,9 +1420,6 @@ int dfs_cache_remount_fs(struct cifs_sb_info *cifs_sb)
 {
 	struct cifs_tcon *tcon;
 	struct TCP_Server_Info *server;
-	struct mount_group *mg;
-	struct cifs_ses *sessions[CACHE_MAX_ENTRIES + 1] = {NULL};
-	int rc;
 
 	if (!cifs_sb || !cifs_sb->master_tlink)
 		return -EINVAL;
@@ -1473,21 +1436,6 @@ int dfs_cache_remount_fs(struct cifs_sb_info *cifs_sb)
 		cifs_dbg(FYI, "%s: no dfs mount group id\n", __func__);
 		return -EINVAL;
 	}
-
-	mutex_lock(&mount_group_list_lock);
-	mg = find_mount_group_locked(&cifs_sb->dfs_mount_id);
-	if (IS_ERR(mg)) {
-		mutex_unlock(&mount_group_list_lock);
-		cifs_dbg(FYI, "%s: no ipc session for refreshing referral\n", __func__);
-		return PTR_ERR(mg);
-	}
-	kref_get(&mg->refcount);
-	mutex_unlock(&mount_group_list_lock);
-
-	spin_lock(&mg->lock);
-	memcpy(&sessions, mg->sessions, mg->num_sessions * sizeof(mg->sessions[0]));
-	spin_unlock(&mg->lock);
-
 	/*
 	 * After reconnecting to a different server, unique ids won't match anymore, so we disable
 	 * serverino. This prevents dentry revalidation to think the dentry are stale (ESTALE).
@@ -1498,17 +1446,15 @@ int dfs_cache_remount_fs(struct cifs_sb_info *cifs_sb)
 	 * that have different prefix paths.
 	 */
 	cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
-	rc = refresh_tcon(sessions, tcon, true);
 
-	kref_put(&mg->refcount, mount_group_release);
-	return rc;
+	return refresh_tcon(tcon, true);
 }
 
 /*
- * Refresh all active dfs mounts regardless of whether they are in cache or not.
- * (cache can be cleared)
+ * Worker that will refresh DFS cache from all active mounts based on lowest TTL value
+ * from a DFS referral.
  */
-static void refresh_mounts(struct cifs_ses **sessions)
+static void refresh_cache_worker(struct work_struct *work)
 {
 	struct TCP_Server_Info *server;
 	struct cifs_ses *ses;
@@ -1523,9 +1469,19 @@ static void refresh_mounts(struct cifs_ses **sessions)
 			continue;
 
 		list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
+			struct cifs_ses *root_ses = CIFS_DFS_ROOT_SES(ses);
+
+			spin_lock(&root_ses->ses_lock);
+			if (root_ses->ses_status != SES_GOOD) {
+				spin_unlock(&root_ses->ses_lock);
+				continue;
+			}
+			spin_unlock(&root_ses->ses_lock);
+
 			list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
 				spin_lock(&tcon->tc_lock);
-				if (!tcon->ipc && !tcon->need_reconnect) {
+				if (!tcon->ipc && tcon->status != TID_NEW &&
+				    tcon->status != TID_NEED_TCON) {
 					tcon->tc_count++;
 					list_add_tail(&tcon->ulist, &tcons);
 				}
@@ -1542,57 +1498,11 @@ static void refresh_mounts(struct cifs_ses **sessions)
 
 		mutex_lock(&server->refpath_lock);
 		if (server->leaf_fullpath)
-			__refresh_tcon(server->leaf_fullpath + 1, sessions, tcon, false);
+			__refresh_tcon(server->leaf_fullpath + 1, tcon, false);
 		mutex_unlock(&server->refpath_lock);
 
 		cifs_put_tcon(tcon);
 	}
-}
-
-/*
- * Worker that will refresh DFS cache and active mounts based on lowest TTL value from a DFS
- * referral.
- */
-static void refresh_cache_worker(struct work_struct *work)
-{
-	struct list_head mglist;
-	struct mount_group *mg, *tmp_mg;
-	struct cifs_ses *sessions[CACHE_MAX_ENTRIES + 1] = {NULL};
-	int max_sessions = ARRAY_SIZE(sessions) - 1;
-	int i = 0, count;
-
-	INIT_LIST_HEAD(&mglist);
-
-	/* Get refereces of mount groups */
-	mutex_lock(&mount_group_list_lock);
-	list_for_each_entry(mg, &mount_group_list, list) {
-		kref_get(&mg->refcount);
-		list_add(&mg->refresh_list, &mglist);
-	}
-	mutex_unlock(&mount_group_list_lock);
-
-	/* Fill in local array with an NULL-terminated list of all referral server sessions */
-	list_for_each_entry(mg, &mglist, refresh_list) {
-		if (i >= max_sessions)
-			break;
-
-		spin_lock(&mg->lock);
-		if (i + mg->num_sessions > max_sessions)
-			count = max_sessions - i;
-		else
-			count = mg->num_sessions;
-		memcpy(&sessions[i], mg->sessions, count * sizeof(mg->sessions[0]));
-		spin_unlock(&mg->lock);
-		i += count;
-	}
-
-	if (sessions[0])
-		refresh_mounts(sessions);
-
-	list_for_each_entry_safe(mg, tmp_mg, &mglist, refresh_list) {
-		list_del_init(&mg->refresh_list);
-		kref_put(&mg->refcount, mount_group_release);
-	}
 
 	spin_lock(&cache_ttl_lock);
 	queue_delayed_work(dfscache_wq, &refresh_task, cache_ttl * HZ);