X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=fs%2Fcifs%2Fdfs_cache.c;h=3bc1d3494be3a55ad408ce86cf7b3e29035499d5;hb=38044859deee1e00fcabf468a7f8442d276d855b;hp=e70915ad754100364c62e509357f412d1b49f9e9;hpb=d79dcde0bc413efd35dd7eabe2d5eed34ec6deb0;p=platform%2Fkernel%2Flinux-starfive.git

diff --git a/fs/cifs/dfs_cache.c b/fs/cifs/dfs_cache.c
index e70915a..3bc1d34 100644
--- a/fs/cifs/dfs_cache.c
+++ b/fs/cifs/dfs_cache.c
@@ -792,26 +792,27 @@ static int get_dfs_referral(const unsigned int xid, struct cifs_ses *ses, const
  */
 static int cache_refresh_path(const unsigned int xid, struct cifs_ses *ses, const char *path)
 {
-	int rc;
-	struct cache_entry *ce;
 	struct dfs_info3_param *refs = NULL;
+	struct cache_entry *ce;
 	int numrefs = 0;
-	bool newent = false;
+	int rc;
 
 	cifs_dbg(FYI, "%s: search path: %s\n", __func__, path);
 
-	down_write(&htable_rw_lock);
+	down_read(&htable_rw_lock);
 
 	ce = lookup_cache_entry(path);
-	if (!IS_ERR(ce)) {
-		if (!cache_entry_expired(ce)) {
-			dump_ce(ce);
-			up_write(&htable_rw_lock);
-			return 0;
-		}
-	} else {
-		newent = true;
+	if (!IS_ERR(ce) && !cache_entry_expired(ce)) {
+		up_read(&htable_rw_lock);
+		return 0;
 	}
+	/*
+	 * Unlock shared access as we don't want to hold any locks while getting
+	 * a new referral.  The @ses used for performing the I/O could be
+	 * reconnecting and it acquires @htable_rw_lock to look up the dfs cache
+	 * in order to failover -- if necessary.
+	 */
+	up_read(&htable_rw_lock);
 
 	/*
 	 * Either the entry was not found, or it is expired.
@@ -819,19 +820,22 @@ static int cache_refresh_path(const unsigned int xid, struct cifs_ses *ses, cons
 	 */
 	rc = get_dfs_referral(xid, ses, path, &refs, &numrefs);
 	if (rc)
-		goto out_unlock;
+		goto out;
 
 	dump_refs(refs, numrefs);
 
-	if (!newent) {
-		rc = update_cache_entry_locked(ce, refs, numrefs);
-		goto out_unlock;
+	down_write(&htable_rw_lock);
+	/* Re-check as another task might have it added or refreshed already */
+	ce = lookup_cache_entry(path);
+	if (!IS_ERR(ce)) {
+		if (cache_entry_expired(ce))
+			rc = update_cache_entry_locked(ce, refs, numrefs);
+	} else {
+		rc = add_cache_entry_locked(refs, numrefs);
 	}
 
-	rc = add_cache_entry_locked(refs, numrefs);
-
-out_unlock:
 	up_write(&htable_rw_lock);
+out:
 	free_dfs_info_array(refs, numrefs);
 	return rc;
 }
@@ -1046,10 +1050,10 @@ int dfs_cache_update_tgthint(const unsigned int xid, struct cifs_ses *ses,
 			     const struct nls_table *cp, int remap, const char *path,
 			     const struct dfs_cache_tgt_iterator *it)
 {
-	int rc;
-	const char *npath;
-	struct cache_entry *ce;
 	struct cache_dfs_tgt *t;
+	struct cache_entry *ce;
+	const char *npath;
+	int rc = 0;
 
 	npath = dfs_cache_canonical_path(path, cp, remap);
 	if (IS_ERR(npath))