[PATCH] const struct tty_operations

As part of an SMP cleanliness pass over UML, I consted a bunch of
structures in order to not have to document their locking.  One of these
structures was a struct tty_operations.  In order to const it in UML
without introducing compiler complaints, the declaration of
tty_set_operations needs to be changed, and then all of its callers need to
be fixed.

This patch declares all struct tty_operations in the tree as const.  In all
cases, they are static and used only as input to tty_set_operations.  As an
extra check, I ran an i386 allyesconfig build which produced no extra
warnings.

53 drivers are affected.  I checked the history of a bunch of them, and in
most cases, there have been only a handful of maintenance changes in the
last six months.  serial_core.c was the busiest one that I looked at.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 6 insertions, 7 deletions

diff --git a/arch/um/drivers/line.c b/arch/um/drivers/line.c
index 563ce7690a1..24747a41378 100644
--- a/arch/um/drivers/line.c
+++ b/arch/um/drivers/line.c
@@ -642,9 +642,9 @@ int line_remove(struct line *lines, unsigned int num, int n)
 }
 
 struct tty_driver *line_register_devfs(struct lines *set,
-                         struct line_driver *line_driver,
-                         struct tty_operations *ops, struct line *lines,
-                         int nlines)
+                                       struct line_driver *line_driver,
+                                       const struct tty_operations *ops,
+                                       struct line *lines, int nlines)
 {
         int i;
         struct tty_driver *driver = alloc_tty_driver(nlines);
diff --git a/arch/um/include/line.h b/arch/um/include/line.h
index 642c9a0320f..7be24811bb3 100644
--- a/arch/um/include/line.h
+++ b/arch/um/include/line.h
@@ -91,10 +91,9 @@ extern int line_setup_irq(int fd, int input, int output, struct line *line,
                           void *data);
 extern void line_close_chan(struct line *line);
 extern struct tty_driver * line_register_devfs(struct lines *set,
-                                struct line_driver *line_driver,
-                                struct tty_operations *driver,
-                                struct line *lines,
-                                int nlines);
+                                               struct line_driver *line_driver,
+                                               const struct tty_operations *driver,
+                                               struct line *lines, int nlines);
 extern void lines_init(struct line *lines, int nlines, struct chan_opts *opts);
 extern void close_lines(struct line *lines, int nlines);