Monitor marking dirty activity of underlying upper inode
so that we have chance to mark overlayfs' own inode dirty.
Signed-off-by: Chengguang Xu <cgxu519@xxxxxxxxxxxx>
---
fs/overlayfs/inode.c | 4 +++-
fs/overlayfs/overlayfs.h | 2 ++
fs/overlayfs/ovl_entry.h | 2 ++
fs/overlayfs/super.c | 11 +++++++++++
fs/overlayfs/util.c | 34 ++++++++++++++++++++++++++++++++++
5 files changed, 52 insertions(+), 1 deletion(-)
diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index b584dca..e75c7ec 100644
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -632,8 +632,10 @@ void ovl_inode_init(struct inode *inode, struct ovl_inode_params *oip,
{
struct inode *realinode;
- if (oip->upperdentry)
+ if (oip->upperdentry) {
OVL_I(inode)->__upperdentry = oip->upperdentry;
+ ovl_register_mark_dirty_notify(OVL_I(inode));
+ }
if (oip->lowerpath && oip->lowerpath->dentry)
OVL_I(inode)->lower = igrab(d_inode(oip->lowerpath->dentry));
if (oip->lowerdata)
diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
index 7bce246..04ef778 100644
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -247,6 +247,8 @@ static inline bool ovl_open_flags_need_copy_up(int flags)
}
/* util.c */
+void ovl_register_mark_dirty_notify(struct ovl_inode *oi);
+void ovl_unregister_mark_dirty_notify(struct ovl_inode *oi);
int ovl_want_write(struct dentry *dentry);
void ovl_drop_write(struct dentry *dentry);
struct dentry *ovl_workdir(struct dentry *dentry);
diff --git a/fs/overlayfs/ovl_entry.h b/fs/overlayfs/ovl_entry.h
index 1b5a2094..fce5314 100644
--- a/fs/overlayfs/ovl_entry.h
+++ b/fs/overlayfs/ovl_entry.h
@@ -129,6 +129,8 @@ struct ovl_inode {
/* synchronize copy up and more */
struct mutex lock;
+ /* moniter marking dirty behavior of upper inode */
+ struct notifier_block mark_dirty_nb;
};
static inline struct ovl_inode *OVL_I(struct inode *inode)
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index dc22725..6d8f9da 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -390,11 +390,22 @@ static int ovl_remount(struct super_block *sb, int *flags, char *data)
return ret;
}
+void ovl_evict_inode(struct inode *inode)
+{
+ struct inode *upper;
+
+ upper = ovl_inode_upper(inode);
+ if (upper)
+ ovl_unregister_mark_dirty_notify(OVL_I(inode));
+ clear_inode(inode);
+}
+
static const struct super_operations ovl_super_operations = {
.alloc_inode = ovl_alloc_inode,
.free_inode = ovl_free_inode,
.destroy_inode = ovl_destroy_inode,
.drop_inode = generic_delete_inode,
+ .evict_inode = ovl_evict_inode,
.put_super = ovl_put_super,
.sync_fs = ovl_sync_fs,
.statfs = ovl_statfs,
diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c
index 23f4756..bdcfe55 100644
--- a/fs/overlayfs/util.c
+++ b/fs/overlayfs/util.c
@@ -417,6 +417,7 @@ void ovl_inode_update(struct inode *inode, struct dentry *upperdentry)
inode->i_private = upperinode;
__insert_inode_hash(inode, (unsigned long) upperinode);
}
+ ovl_register_mark_dirty_notify(OVL_I(inode));
}
static void ovl_dentry_version_inc(struct dentry *dentry, bool impurity)
@@ -950,3 +951,36 @@ char *ovl_get_redirect_xattr(struct ovl_fs *ofs, struct dentry *dentry,
kfree(buf);
return ERR_PTR(res);
}
+
+int ovl_inode_dirty_notify(struct notifier_block *nb,
+ unsigned long dummy, void *param)
+{
+ struct ovl_inode *oi = container_of(nb, struct ovl_inode, mark_dirty_nb);
+ int *flags = (int *)param;
+
+ // add later
+ //__mark_inode_dirty(&oi->vfs_inode, *flags);
+ return NOTIFY_OK;
+}
+
+void ovl_register_mark_dirty_notify(struct ovl_inode *oi)
+{
+ struct inode *upper;
+
+ upper = oi->__upperdentry->d_inode;
+ oi->mark_dirty_nb.notifier_call = ovl_inode_dirty_notify;
+
+ blocking_notifier_chain_register(
+ &upper->notifier_lists[MARK_INODE_DIRTY_NOTIFIER],
+ &oi->mark_dirty_nb);
+}
+
+void ovl_unregister_mark_dirty_notify(struct ovl_inode *oi)
+{
+ struct inode *upper;
+
+ upper = oi->__upperdentry->d_inode;
+ blocking_notifier_chain_unregister(
+ &upper->notifier_lists[MARK_INODE_DIRTY_NOTIFIER],
+ &oi->mark_dirty_nb);
+}
--
1.8.3.1
