eCryptfs: Remove ecryptfs_unlink_sigs warnings

A feature was added to the eCryptfs umount helper to automatically
unlink the keys used for an eCryptfs mount from the kernel keyring upon
umount.  This patch keeps the unrecognized mount option warnings for
ecryptfs_unlink_sigs out of the logs.
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>

fs/ecryptfs/ecryptfs_kernel.h

@@ -269,6 +269,7 @@ struct ecryptfs_crypt_stat {
 #define ECRYPTFS_ENCRYPT_FILENAMES    0x00000800
 #define ECRYPTFS_ENCFN_USE_MOUNT_FNEK 0x00001000
 #define ECRYPTFS_ENCFN_USE_FEK        0x00002000
+#define ECRYPTFS_UNLINK_SIGS	      0x00004000
 	u32 flags;
 	unsigned int file_version;
 	size_t iv_bytes;

fs/ecryptfs/main.c

@@ -208,7 +208,7 @@ enum { ecryptfs_opt_sig, ecryptfs_opt_ecryptfs_sig,
        ecryptfs_opt_passthrough, ecryptfs_opt_xattr_metadata,
        ecryptfs_opt_encrypted_view, ecryptfs_opt_fnek_sig,
        ecryptfs_opt_fn_cipher, ecryptfs_opt_fn_cipher_key_bytes,
-       ecryptfs_opt_err };
+       ecryptfs_opt_unlink_sigs, ecryptfs_opt_err };
 
 static const match_table_t tokens = {
 	{ecryptfs_opt_sig, "sig=%s"},
@@ -222,6 +222,7 @@ static const match_table_t tokens = {
 	{ecryptfs_opt_fnek_sig, "ecryptfs_fnek_sig=%s"},
 	{ecryptfs_opt_fn_cipher, "ecryptfs_fn_cipher=%s"},
 	{ecryptfs_opt_fn_cipher_key_bytes, "ecryptfs_fn_key_bytes=%u"},
+	{ecryptfs_opt_unlink_sigs, "ecryptfs_unlink_sigs"},
 	{ecryptfs_opt_err, NULL}
 };
 
@@ -402,6 +403,9 @@ static int ecryptfs_parse_options(struct super_block *sb, char *options)
 				fn_cipher_key_bytes;
 			fn_cipher_key_bytes_set = 1;
 			break;
+		case ecryptfs_opt_unlink_sigs:
+			mount_crypt_stat->flags |= ECRYPTFS_UNLINK_SIGS;
+			break;
 		case ecryptfs_opt_err:
 		default:
 			printk(KERN_WARNING

fs/ecryptfs/super.c

@@ -189,6 +189,8 @@ static int ecryptfs_show_options(struct seq_file *m, struct vfsmount *mnt)
 		seq_printf(m, ",ecryptfs_xattr_metadata");
 	if (mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED)
 		seq_printf(m, ",ecryptfs_encrypted_view");
+	if (mount_crypt_stat->flags & ECRYPTFS_UNLINK_SIGS)
+		seq_printf(m, ",ecryptfs_unlink_sigs");
 
 	return 0;
 }