Take fs_struct handling to new file (fs/fs_struct.c)

Pure code move; two new helper functions for nfsd and daemonize
(unshare_fs_struct() and daemonize_fs_struct() resp.; for now -
the same code as used to be in callers).  unshare_fs_struct()
exported (for nfsd, as copy_fs_struct()/exit_fs() used to be),
copy_fs_struct() and exit_fs() don't need exports anymore.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 2 insertions, 27 deletions

diff --git a/kernel/fork.c b/kernel/fork.c
index 47c1584..05c02dc 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -681,38 +681,13 @@ fail_nomem:
 	return retval;
 }
 
-static struct fs_struct *__copy_fs_struct(struct fs_struct *old)
-{
-	struct fs_struct *fs = kmem_cache_alloc(fs_cachep, GFP_KERNEL);
-	/* We don't need to lock fs - think why ;-) */
-	if (fs) {
-		atomic_set(&fs->count, 1);
-		rwlock_init(&fs->lock);
-		fs->umask = old->umask;
-		read_lock(&old->lock);
-		fs->root = old->root;
-		path_get(&old->root);
-		fs->pwd = old->pwd;
-		path_get(&old->pwd);
-		read_unlock(&old->lock);
-	}
-	return fs;
-}
-
-struct fs_struct *copy_fs_struct(struct fs_struct *old)
-{
-	return __copy_fs_struct(old);
-}
-
-EXPORT_SYMBOL_GPL(copy_fs_struct);
-
 static int copy_fs(unsigned long clone_flags, struct task_struct *tsk)
 {
 	if (clone_flags & CLONE_FS) {
 		atomic_inc(&current->fs->count);
 		return 0;
 	}
-	tsk->fs = __copy_fs_struct(current->fs);
+	tsk->fs = copy_fs_struct(current->fs);
 	if (!tsk->fs)
 		return -ENOMEM;
 	return 0;
@@ -1545,7 +1520,7 @@ static int unshare_fs(unsigned long unshare_flags, struct fs_struct **new_fsp)
 
 	if ((unshare_flags & CLONE_FS) &&
 	    (fs && atomic_read(&fs->count) > 1)) {
-		*new_fsp = __copy_fs_struct(current->fs);
+		*new_fsp = copy_fs_struct(current->fs);
 		if (!*new_fsp)
 			return -ENOMEM;
 	}