[SERIAL] Clean up serial locking when obtaining a reference to a port
The locking for the uart_port is over complicated, and can be
simplified if we introduce a flag to indicate that a port is "dead"
and will be removed.
This also helps the validator because it removes a case of non-nested
unlock ordering.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index c32e60e..bd14858 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -254,6 +254,7 @@
#define UPF_CONS_FLOW ((__force upf_t) (1 << 23))
#define UPF_SHARE_IRQ ((__force upf_t) (1 << 24))
#define UPF_BOOT_AUTOCONF ((__force upf_t) (1 << 28))
+#define UPF_DEAD ((__force upf_t) (1 << 30))
#define UPF_IOREMAP ((__force upf_t) (1 << 31))
#define UPF_CHANGE_MASK ((__force upf_t) (0x17fff))