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authorJiri Slaby <jslaby@suse.cz>2021-11-26 09:15:57 +0100
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2021-11-26 16:27:42 +0100
commit4072254f96f954ec0d34899f15d987803b6d76a2 (patch)
treea5e94e1d58e39cbfb962ae3b3590192fddacdf0f /include/linux/tty.h
parent40f4268cddb93d17a11579920d940c2dca8b9445 (diff)
tty: reformat tty_struct::flags into kernel-doc
Move the partial tty_struct::flags documentation from tty_ldisc to the tty.h header and combine it with the one-liners present there. Convert all those to kernel-doc. This way, we can simply reference the documentation in Documentation while the text is still along the definitions. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20211126081611.11001-10-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/linux/tty.h')
-rw-r--r--include/linux/tty.h74
1 files changed, 60 insertions, 14 deletions
diff --git a/include/linux/tty.h b/include/linux/tty.h
index da49ad9be281..7b0a5d478ef6 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -263,26 +263,72 @@ struct tty_file_private {
/* tty magic number */
#define TTY_MAGIC 0x5401
-/*
- * These bits are used in the flags field of the tty structure.
+/**
+ * DOC: TTY Struct Flags
+ *
+ * These bits are used in the :c:member:`tty_struct.flags` field.
*
* So that interrupts won't be able to mess up the queues,
* copy_to_cooked must be atomic with respect to itself, as must
* tty->write. Thus, you must use the inline functions set_bit() and
* clear_bit() to make things atomic.
+ *
+ * TTY_THROTTLED
+ * Driver input is throttled. The ldisc should call
+ * :c:member:`tty_driver.unthrottle()` in order to resume reception when
+ * it is ready to process more data (at threshold min).
+ *
+ * TTY_IO_ERROR
+ * If set, causes all subsequent userspace read/write calls on the tty to
+ * fail, returning -%EIO. (May be no ldisc too.)
+ *
+ * TTY_OTHER_CLOSED
+ * Device is a pty and the other side has closed.
+ *
+ * TTY_EXCLUSIVE
+ * Exclusive open mode (a single opener).
+ *
+ * TTY_DO_WRITE_WAKEUP
+ * If set, causes the driver to call the
+ * :c:member:`tty_ldisc_ops.write_wakeup()` method in order to resume
+ * transmission when it can accept more data to transmit.
+ *
+ * TTY_LDISC_OPEN
+ * Indicates that a line discipline is open. For debugging purposes only.
+ *
+ * TTY_PTY_LOCK
+ * A flag private to pty code to implement %TIOCSPTLCK/%TIOCGPTLCK logic.
+ *
+ * TTY_NO_WRITE_SPLIT
+ * Prevent driver from splitting up writes into smaller chunks (preserve
+ * write boundaries to driver).
+ *
+ * TTY_HUPPED
+ * The TTY was hung up. This is set post :c:member:`tty_driver.hangup()`.
+ *
+ * TTY_HUPPING
+ * The TTY is in the process of hanging up to abort potential readers.
+ *
+ * TTY_LDISC_CHANGING
+ * Line discipline for this TTY is being changed. I/O should not block
+ * when this is set. Use tty_io_nonblock() to check.
+ *
+ * TTY_LDISC_HALTED
+ * Line discipline for this TTY was stopped. No work should be queued to
+ * this ldisc.
*/
-#define TTY_THROTTLED 0 /* Call unthrottle() at threshold min */
-#define TTY_IO_ERROR 1 /* Cause an I/O error (may be no ldisc too) */
-#define TTY_OTHER_CLOSED 2 /* Other side (if any) has closed */
-#define TTY_EXCLUSIVE 3 /* Exclusive open mode */
-#define TTY_DO_WRITE_WAKEUP 5 /* Call write_wakeup after queuing new */
-#define TTY_LDISC_OPEN 11 /* Line discipline is open */
-#define TTY_PTY_LOCK 16 /* pty private */
-#define TTY_NO_WRITE_SPLIT 17 /* Preserve write boundaries to driver */
-#define TTY_HUPPED 18 /* Post driver->hangup() */
-#define TTY_HUPPING 19 /* Hangup in progress */
-#define TTY_LDISC_CHANGING 20 /* Change pending - non-block IO */
-#define TTY_LDISC_HALTED 22 /* Line discipline is halted */
+#define TTY_THROTTLED 0
+#define TTY_IO_ERROR 1
+#define TTY_OTHER_CLOSED 2
+#define TTY_EXCLUSIVE 3
+#define TTY_DO_WRITE_WAKEUP 5
+#define TTY_LDISC_OPEN 11
+#define TTY_PTY_LOCK 16
+#define TTY_NO_WRITE_SPLIT 17
+#define TTY_HUPPED 18
+#define TTY_HUPPING 19
+#define TTY_LDISC_CHANGING 20
+#define TTY_LDISC_HALTED 22
static inline bool tty_io_nonblock(struct tty_struct *tty, struct file *file)
{