xfs: remove nr_to_write writeback windup.

[safe/jmp/linux-2.6] / kernel / utsname.c

diff --git a/kernel/utsname.c b/kernel/utsname.c
index c859164..8a82b4b 100644 (file)
--- a/kernel/utsname.c
+++ b/kernel/utsname.c
@@ -12,7 +12,18 @@
 #include <linux/module.h>
 #include <linux/uts.h>
 #include <linux/utsname.h>
-#include <linux/version.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+
+static struct uts_namespace *create_uts_ns(void)
+{
+       struct uts_namespace *uts_ns;
+
+       uts_ns = kmalloc(sizeof(struct uts_namespace), GFP_KERNEL);
+       if (uts_ns)
+               kref_init(&uts_ns->kref);
+       return uts_ns;
+}
 
 /*
  * Clone a new ns copying an original utsname, setting refcount to 1
@@ -23,30 +34,14 @@ static struct uts_namespace *clone_uts_ns(struct uts_namespace *old_ns)
 {
        struct uts_namespace *ns;
 
-       ns = kmalloc(sizeof(struct uts_namespace), GFP_KERNEL);
-       if (ns) {
-               memcpy(&ns->name, &old_ns->name, sizeof(ns->name));
-               kref_init(&ns->kref);
-       }
-       return ns;
-}
-
-/*
- * unshare the current process' utsname namespace.
- * called only in sys_unshare()
- */
-int unshare_utsname(unsigned long unshare_flags, struct uts_namespace **new_uts)
-{
-       if (unshare_flags & CLONE_NEWUTS) {
-               if (!capable(CAP_SYS_ADMIN))
-                       return -EPERM;
-
-               *new_uts = clone_uts_ns(current->nsproxy->uts_ns);
-               if (!*new_uts)
-                       return -ENOMEM;
-       }
+       ns = create_uts_ns();
+       if (!ns)
+               return ERR_PTR(-ENOMEM);
 
-       return 0;
+       down_read(&uts_sem);
+       memcpy(&ns->name, &old_ns->name, sizeof(ns->name));
+       up_read(&uts_sem);
+       return ns;
 }
 
 /*
@@ -55,35 +50,20 @@ int unshare_utsname(unsigned long unshare_flags, struct uts_namespace **new_uts)
  * utsname of this process won't be seen by parent, and vice
  * versa.
  */
-int copy_utsname(int flags, struct task_struct *tsk)
+struct uts_namespace *copy_utsname(unsigned long flags, struct uts_namespace *old_ns)
 {
-       struct uts_namespace *old_ns = tsk->nsproxy->uts_ns;
        struct uts_namespace *new_ns;
-       int err = 0;
-
-       if (!old_ns)
-               return 0;
 
+       BUG_ON(!old_ns);
        get_uts_ns(old_ns);
 
        if (!(flags & CLONE_NEWUTS))
-               return 0;
-
-       if (!capable(CAP_SYS_ADMIN)) {
-               err = -EPERM;
-               goto out;
-       }
+               return old_ns;
 
        new_ns = clone_uts_ns(old_ns);
-       if (!new_ns) {
-               err = -ENOMEM;
-               goto out;
-       }
-       tsk->nsproxy->uts_ns = new_ns;
 
-out:
        put_uts_ns(old_ns);
-       return err;
+       return new_ns;
 }
 
 void free_uts_ns(struct kref *kref)