[PATCH] uml: redo console locking

Fix some console locking problems (including scheduling in atomic) and various
reorderings and cleanup in that code.  Not yet ready for 2.6.12 probably.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 18 insertions, 18 deletions

diff --git a/arch/um/include/line.h b/arch/um/include/line.h
index 6d81ecc17be5..4c5e92c04ccb 100644
--- a/arch/um/include/line.h
+++ b/arch/um/include/line.h
@@ -10,7 +10,7 @@
 #include "linux/workqueue.h"
 #include "linux/tty.h"
 #include "linux/interrupt.h"
-#include "asm/semaphore.h"
+#include "linux/spinlock.h"
 #include "chan_user.h"
 #include "mconsole_kern.h"
 
@@ -37,10 +37,18 @@ struct line {
         struct list_head chan_list;
         int valid;
         int count;
-        struct semaphore sem;
+        /*This lock is actually, mostly, local to*/
+        spinlock_t lock;
+
+        /* Yes, this is a real circular buffer.
+         * XXX: And this should become a struct kfifo!
+         *
+         * buffer points to a buffer allocated on demand, of length
+         * LINE_BUFSIZE, head to the start of the ring, tail to the end.*/
         char *buffer;
         char *head;
         char *tail;
+
         int sigio;
         struct work_struct task;
         struct line_driver *driver;
@@ -52,7 +60,6 @@ struct line {
           init_pri :    INIT_STATIC, \
           chan_list :   { }, \
           valid :       1, \
-          sem :         { }, \
           buffer :      NULL, \
           head :        NULL, \
           tail :        NULL, \
@@ -69,15 +76,18 @@ struct lines {
 extern void line_close(struct tty_struct *tty, struct file * filp);
 extern int line_open(struct line *lines, struct tty_struct *tty, 
                      struct chan_opts *opts);
-extern int line_setup(struct line *lines, int num, char *init, 
+extern int line_setup(struct line *lines, unsigned int sizeof_lines, char *init,
                       int all_allowed);
 extern int line_write(struct tty_struct *tty, const unsigned char *buf, int len);
 extern void line_put_char(struct tty_struct *tty, unsigned char ch);
 extern void line_set_termios(struct tty_struct *tty, struct termios * old);
 extern int line_chars_in_buffer(struct tty_struct *tty);
+extern void line_flush_buffer(struct tty_struct *tty);
+extern void line_flush_chars(struct tty_struct *tty);
 extern int line_write_room(struct tty_struct *tty);
 extern int line_ioctl(struct tty_struct *tty, struct file * file,
                       unsigned int cmd, unsigned long arg);
+
 extern char *add_xterm_umid(char *base);
 extern int line_setup_irq(int fd, int input, int output, struct tty_struct *tty);
 extern void line_close_chan(struct line *line);
@@ -89,20 +99,10 @@ extern struct tty_driver * line_register_devfs(struct lines *set,
                                 int nlines);
 extern void lines_init(struct line *lines, int nlines);
 extern void close_lines(struct line *lines, int nlines);
-extern int line_config(struct line *lines, int num, char *str);
-extern int line_remove(struct line *lines, int num, char *str);
-extern int line_get_config(char *dev, struct line *lines, int num, char *str, 
+
+extern int line_config(struct line *lines, unsigned int sizeof_lines, char *str);
+extern int line_remove(struct line *lines, unsigned int sizeof_lines, char *str);
+extern int line_get_config(char *dev, struct line *lines, unsigned int sizeof_lines, char *str,
                            int size, char **error_out);
 
 #endif
-
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-file-style: "linux"
- * End:
- */