[PATCH] uml: return hotplug errors to host

I noticed that errors happening while hotplugging devices from the host were
never returned back to the mconsole client.  In some cases, success was
returned instead of even an information-free error.

This patch cleans that up by having the low-level configuration code pass back
an error string along with an error code.  At the top level, which knows
whether it is early boot time or responding to an mconsole request, the string
is printk'd or returned to the mconsole client.

There are also whitespace and trivial code cleanups in the surrounding code.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 5 insertions, 3 deletions

diff --git a/arch/um/include/line.h b/arch/um/include/line.h
index b79643eeee08..a2486b4cc9fe 100644
--- a/arch/um/include/line.h
+++ b/arch/um/include/line.h
@@ -76,7 +76,7 @@ struct lines {
 extern void line_close(struct tty_struct *tty, struct file * filp);
 extern int line_open(struct line *lines, struct tty_struct *tty);
 extern int line_setup(struct line *lines, unsigned int sizeof_lines,
-                      char *init);
+                      char *init, char **error_out);
 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);
@@ -102,9 +102,11 @@ extern void lines_init(struct line *lines, int nlines, struct chan_opts *opts);
 extern void close_lines(struct line *lines, int nlines);
 
 extern int line_config(struct line *lines, unsigned int sizeof_lines,
-                       char *str, const struct chan_opts *opts);
+                       char *str, const struct chan_opts *opts,
+                       char **error_out);
 extern int line_id(char **str, int *start_out, int *end_out);
-extern int line_remove(struct line *lines, unsigned int sizeof_lines, int n);
+extern int line_remove(struct line *lines, unsigned int sizeof_lines, int n,
+                       char **error_out);
 extern int line_get_config(char *dev, struct line *lines,
                            unsigned int sizeof_lines, char *str,
                            int size, char **error_out);