vfs: add helpers to get root and pwd
Add three helpers that retrieve a refcounted copy of the root and cwd
from the supplied fs_struct.
get_fs_root()
get_fs_pwd()
get_fs_root_and_pwd()
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/proc/base.c b/fs/proc/base.c
index c806dfb..4cf5abf 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -149,18 +149,13 @@
return count;
}
-static int get_fs_path(struct task_struct *task, struct path *path, bool root)
+static int get_task_root(struct task_struct *task, struct path *root)
{
- struct fs_struct *fs;
int result = -ENOENT;
task_lock(task);
- fs = task->fs;
- if (fs) {
- read_lock(&fs->lock);
- *path = root ? fs->root : fs->pwd;
- path_get(path);
- read_unlock(&fs->lock);
+ if (task->fs) {
+ get_fs_root(task->fs, root);
result = 0;
}
task_unlock(task);
@@ -173,7 +168,12 @@
int result = -ENOENT;
if (task) {
- result = get_fs_path(task, path, 0);
+ task_lock(task);
+ if (task->fs) {
+ get_fs_pwd(task->fs, path);
+ result = 0;
+ }
+ task_unlock(task);
put_task_struct(task);
}
return result;
@@ -185,7 +185,7 @@
int result = -ENOENT;
if (task) {
- result = get_fs_path(task, path, 1);
+ result = get_task_root(task, path);
put_task_struct(task);
}
return result;
@@ -597,7 +597,7 @@
get_mnt_ns(ns);
}
rcu_read_unlock();
- if (ns && get_fs_path(task, &root, 1) == 0)
+ if (ns && get_task_root(task, &root) == 0)
ret = 0;
put_task_struct(task);
}