uml: const and other tidying

This patch also does some improvements for uml code.  Improvements include
dropping unnecessary cast, killing some unnecessary code and still some
constifying for pointers etc..

Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 6 insertions, 5 deletions

diff --git a/arch/um/os-Linux/drivers/tuntap_user.c b/arch/um/os-Linux/drivers/tuntap_user.c
index 1037a3b6386e..1d847959d1d6 100644
--- a/arch/um/os-Linux/drivers/tuntap_user.c
+++ b/arch/um/os-Linux/drivers/tuntap_user.c
@@ -148,7 +148,7 @@ static int tuntap_open(void *data)
                 memset(&ifr, 0, sizeof(ifr));
                 ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
                 strlcpy(ifr.ifr_name, pri->dev_name, sizeof(ifr.ifr_name));
-                if (ioctl(pri->fd, TUNSETIFF, (void *) &ifr) < 0) {
+                if (ioctl(pri->fd, TUNSETIFF, &ifr) < 0) {
                         err = -errno;
                         printk(UM_KERN_ERR "TUNSETIFF failed, errno = %d\n",
                                errno);
diff --git a/arch/um/os-Linux/mem.c b/arch/um/os-Linux/mem.c
index c3b736adc1d9..9674ed1bef2f 100644
--- a/arch/um/os-Linux/mem.c
+++ b/arch/um/os-Linux/mem.c
@@ -30,7 +30,7 @@ static char *tempdir = NULL;
 
 static void __init find_tempdir(void)
 {
-        char *dirs[] = { "TMP", "TEMP", "TMPDIR", NULL };
+        const char *dirs[] = { "TMP", "TEMP", "TMPDIR", NULL };
         int i;
         char *dir = NULL;
 
@@ -59,9 +59,10 @@ static void __init find_tempdir(void)
  * read the file as needed.  If there's an error, -errno is returned;
  * if the end of the file is reached, 0 is returned.
  */
-static int next(int fd, char *buf, int size, char c)
+static int next(int fd, char *buf, size_t size, char c)
 {
-        int n, len;
+        ssize_t n;
+        size_t len;
         char *ptr;
 
         while((ptr = strchr(buf, c)) == NULL){
diff --git a/arch/um/os-Linux/sigio.c b/arch/um/os-Linux/sigio.c
index dc03e9cccb63..7243f5733772 100644
--- a/arch/um/os-Linux/sigio.c
+++ b/arch/um/os-Linux/sigio.c
@@ -407,7 +407,7 @@ static int async_pty(int master, int slave)
         if((fcntl(slave, F_SETFL, flags | O_NONBLOCK) < 0))
                 return -errno;
 
-        return(0);
+        return 0;
 }
 
 static void __init check_one_sigio(void (*proc)(int, int))