cifs: new nt status codes from MS-SMB2

MS-SMB2 spec has introduced two new status codes,
STATUS_SERVER_UNAVAILABLE and STATUS_FILE_NOT_AVAILABLE
which are to be treated as retryable errors.

This change adds these to the available mappings and
maps them to Linux errno EAGAIN.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

fs/smb/client/smb2maperror.c

@@ -1210,6 +1210,8 @@ static const struct status_to_posix_error smb2_error_map_table[] = {
 	{STATUS_INVALID_TASK_INDEX, -EIO, "STATUS_INVALID_TASK_INDEX"},
 	{STATUS_THREAD_ALREADY_IN_TASK, -EIO, "STATUS_THREAD_ALREADY_IN_TASK"},
 	{STATUS_CALLBACK_BYPASS, -EIO, "STATUS_CALLBACK_BYPASS"},
+	{STATUS_SERVER_UNAVAILABLE, -EAGAIN, "STATUS_SERVER_UNAVAILABLE"},
+	{STATUS_FILE_NOT_AVAILABLE, -EAGAIN, "STATUS_FILE_NOT_AVAILABLE"},
 	{STATUS_PORT_CLOSED, -EIO, "STATUS_PORT_CLOSED"},
 	{STATUS_MESSAGE_LOST, -EIO, "STATUS_MESSAGE_LOST"},
 	{STATUS_INVALID_MESSAGE, -EIO, "STATUS_INVALID_MESSAGE"},

fs/smb/client/smb2status.h

@@ -982,6 +982,8 @@ struct ntstatus {
 #define STATUS_INVALID_TASK_INDEX cpu_to_le32(0xC0000501)
 #define STATUS_THREAD_ALREADY_IN_TASK cpu_to_le32(0xC0000502)
 #define STATUS_CALLBACK_BYPASS cpu_to_le32(0xC0000503)
+#define STATUS_SERVER_UNAVAILABLE cpu_to_le32(0xC0000466)
+#define STATUS_FILE_NOT_AVAILABLE cpu_to_le32(0xC0000467)
 #define STATUS_PORT_CLOSED cpu_to_le32(0xC0000700)
 #define STATUS_MESSAGE_LOST cpu_to_le32(0xC0000701)
 #define STATUS_INVALID_MESSAGE cpu_to_le32(0xC0000702)