mirror of https://gitee.com/openkylin/linux.git
fef062cbf2
Since at least before 2.6.30, tty drivers that do not drop the tty lock while closing cannot observe ASYNC_CLOSING set while holding the tty lock; this includes the tty driver's open() and hangup() methods, since the tty core calls these methods holding the tty lock. For these drivers, waiting for ASYNC_CLOSING to clear while opening is not required, since this condition cannot occur. Similarly, even when the open() method drops and reacquires the tty lock after blocking, ASYNC_CLOSING cannot be set (again, for drivers that do not drop the tty lock while closing). Now that tty port drivers no longer drop the tty lock while closing (since 'tty: Remove tty_wait_until_sent_from_close()'), the same conditions apply: waiting for ASYNC_CLOSING to clear while opening is not required, nor is re-checking ASYNC_CLOSING after dropping and reacquiring the tty lock while blocking (eg., in *_block_til_ready()). Note: The ASYNC_CLOSING flag state is still maintained since several bitrotting drivers use it for (dubious) other purposes. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
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| .. | ||
| Kconfig | ||
| Makefile | ||
| cm4000_cs.c | ||
| cm4040_cs.c | ||
| cm4040_cs.h | ||
| synclink_cs.c | ||