tmpfs: cleanup mpol_parse_str()

mpol_parse_str() made lots 'err' variable related bug.  Because it is ugly
and reviewing unfriendly.

This patch simplifies it.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Ravikiran Thirumalai <kiran@scalex86.org>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Acked-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index fb71790..6cdfa1d 100644 (file)
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -2195,8 +2195,8 @@ int mpol_parse_str(char *str, struct mempolicy **mpol, int no_context)
                        char *rest = nodelist;
                        while (isdigit(*rest))
                                rest++;
-                       if (!*rest)
-                               err = 0;
+                       if (*rest)
+                               goto out;
                }
                break;
        case MPOL_INTERLEAVE:
@@ -2205,7 +2205,6 @@ int mpol_parse_str(char *str, struct mempolicy **mpol, int no_context)
                 */
                if (!nodelist)
                        nodes = node_states[N_HIGH_MEMORY];
-               err = 0;
                break;
        case MPOL_LOCAL:
                /*
@@ -2214,7 +2213,6 @@ int mpol_parse_str(char *str, struct mempolicy **mpol, int no_context)
                if (nodelist)
                        goto out;
                mode = MPOL_PREFERRED;
-               err = 0;
                break;
        case MPOL_DEFAULT:
                /*
@@ -2229,7 +2227,6 @@ int mpol_parse_str(char *str, struct mempolicy **mpol, int no_context)
                 */
                if (!nodelist)
                        goto out;
-               err = 0;
        }
 
        mode_flags = 0;
@@ -2243,13 +2240,14 @@ int mpol_parse_str(char *str, struct mempolicy **mpol, int no_context)
                else if (!strcmp(flags, "relative"))
                        mode_flags |= MPOL_F_RELATIVE_NODES;
                else
-                       err = 1;
+                       goto out;
        }
 
        new = mpol_new(mode, mode_flags, &nodes);
        if (IS_ERR(new))
-               err = 1;
-       else {
+               goto out;
+
+       {
                int ret;
                NODEMASK_SCRATCH(scratch);
                if (scratch) {
@@ -2260,13 +2258,15 @@ int mpol_parse_str(char *str, struct mempolicy **mpol, int no_context)
                        ret = -ENOMEM;
                NODEMASK_SCRATCH_FREE(scratch);
                if (ret) {
-                       err = 1;
                        mpol_put(new);
-               } else if (no_context) {
-                       /* save for contextualization */
-                       new->w.user_nodemask = nodes;
+                       goto out;
                }
        }
+       err = 0;
+       if (no_context) {
+               /* save for contextualization */
+               new->w.user_nodemask = nodes;
+       }
 
 out:
        /* Restore string for error message */