Revert "kernfs: invoke kernfs_unmap_bin_file() directly from __kernfs_remove()"
This reverts commit f601f9a2bf7dc1f7ee18feece4c4e2fc6845d6c4.
Tejun writes:
I'm sorry but can you please revert the whole series?
get_active() waiting while a node is deactivated has potential
to lead to deadlock and that deactivate/reactivate interface is
something fundamentally flawed and that cgroup will have to work
with the remove_self() like everybody else. IOW, I think the
first posting was correct.
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c
index f878e4f..e565ec0 100644
--- a/fs/kernfs/dir.c
+++ b/fs/kernfs/dir.c
@@ -121,17 +121,13 @@
* Locking:
* mutex_lock(kernfs_mutex)
*/
-static bool kernfs_unlink_sibling(struct kernfs_node *kn)
+static void kernfs_unlink_sibling(struct kernfs_node *kn)
{
- if (RB_EMPTY_NODE(&kn->rb))
- return false;
-
if (kernfs_type(kn) == KERNFS_DIR)
kn->parent->dir.subdirs--;
rb_erase(&kn->rb, &kn->parent->dir.children);
RB_CLEAR_NODE(&kn->rb);
- return true;
}
/**
@@ -500,6 +496,7 @@
acxt->removed = kn->u.removed_list;
+ kernfs_unmap_bin_file(kn);
kernfs_put(kn);
}
}
@@ -857,44 +854,23 @@
/* unlink the subtree node-by-node */
do {
+ struct kernfs_iattrs *ps_iattr;
+
pos = kernfs_leftmost_descendant(kn);
- /*
- * We're gonna release kernfs_mutex to unmap bin files,
- * Make sure @pos doesn't go away inbetween.
- */
- kernfs_get(pos);
-
- /*
- * This must be come before unlinking; otherwise, when
- * there are multiple removers, some may finish before
- * unmapping is complete.
- */
- if (pos->flags & KERNFS_HAS_MMAP) {
- mutex_unlock(&kernfs_mutex);
- kernfs_unmap_file(pos);
- mutex_lock(&kernfs_mutex);
- }
-
- /*
- * kernfs_unlink_sibling() succeeds once per node. Use it
- * to decide who's responsible for cleanups.
- */
- if (!pos->parent || kernfs_unlink_sibling(pos)) {
- struct kernfs_iattrs *ps_iattr =
- pos->parent ? pos->parent->iattr : NULL;
+ if (pos->parent) {
+ kernfs_unlink_sibling(pos);
/* update timestamps on the parent */
+ ps_iattr = pos->parent->iattr;
if (ps_iattr) {
ps_iattr->ia_iattr.ia_ctime = CURRENT_TIME;
ps_iattr->ia_iattr.ia_mtime = CURRENT_TIME;
}
-
- pos->u.removed_list = acxt->removed;
- acxt->removed = pos;
}
- kernfs_put(pos);
+ pos->u.removed_list = acxt->removed;
+ acxt->removed = pos;
} while (pos != kn);
}
diff --git a/fs/kernfs/file.c b/fs/kernfs/file.c
index 404ffd2..231a171 100644
--- a/fs/kernfs/file.c
+++ b/fs/kernfs/file.c
@@ -700,11 +700,14 @@
return 0;
}
-void kernfs_unmap_file(struct kernfs_node *kn)
+void kernfs_unmap_bin_file(struct kernfs_node *kn)
{
struct kernfs_open_node *on;
struct kernfs_open_file *of;
+ if (!(kn->flags & KERNFS_HAS_MMAP))
+ return;
+
spin_lock_irq(&kernfs_open_node_lock);
on = kn->attr.open;
if (on)
diff --git a/fs/kernfs/kernfs-internal.h b/fs/kernfs/kernfs-internal.h
index e9ec38c..57a93f4 100644
--- a/fs/kernfs/kernfs-internal.h
+++ b/fs/kernfs/kernfs-internal.h
@@ -113,7 +113,7 @@
*/
extern const struct file_operations kernfs_file_fops;
-void kernfs_unmap_file(struct kernfs_node *kn);
+void kernfs_unmap_bin_file(struct kernfs_node *kn);
/*
* symlink.c