ceph: use ceph_evict_inode to cleanup inode's resource

[ Upstream commit 87bc5b895d94a0f40fe170d4cf5771c8e8f85d15 ]

remove_session_caps() relies on __wait_on_freeing_inode(), to wait for
freeing inode to remove its caps. But VFS wakes freeing inode waiters
before calling destroy_inode().

[ jlayton: mainline moved to ->free_inode before the original patch was
	   merged. This backport reinstates ceph_destroy_inode and just
	   has it do the call_rcu call. ]

Cc: stable@vger.kernel.org
Link: https://tracker.ceph.com/issues/40102
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

fs/ceph/inode.c

@@ -528,13 +528,16 @@ static void ceph_i_callback(struct rcu_head *head)
 	kmem_cache_free(ceph_inode_cachep, ci);
 }
 
-void ceph_destroy_inode(struct inode *inode)
+void ceph_evict_inode(struct inode *inode)
 {
 	struct ceph_inode_info *ci = ceph_inode(inode);
 	struct ceph_inode_frag *frag;
 	struct rb_node *n;
 
-	dout("destroy_inode %p ino %llx.%llx\n", inode, ceph_vinop(inode));
+	dout("evict_inode %p ino %llx.%llx\n", inode, ceph_vinop(inode));
+
+	truncate_inode_pages_final(&inode->i_data);
+	clear_inode(inode);
 
 	ceph_fscache_unregister_inode_cookie(ci);
 
@@ -576,7 +579,10 @@ void ceph_destroy_inode(struct inode *inode)
 		ceph_buffer_put(ci->i_xattrs.prealloc_blob);
 
 	ceph_put_string(rcu_dereference_raw(ci->i_layout.pool_ns));
+}
 
+void ceph_destroy_inode(struct inode *inode)
+{
 	call_rcu(&inode->i_rcu, ceph_i_callback);
 }
 

fs/ceph/super.c

@@ -830,6 +830,7 @@ static const struct super_operations ceph_super_ops = {
 	.destroy_inode	= ceph_destroy_inode,
 	.write_inode    = ceph_write_inode,
 	.drop_inode	= ceph_drop_inode,
+	.evict_inode	= ceph_evict_inode,
 	.sync_fs        = ceph_sync_fs,
 	.put_super	= ceph_put_super,
 	.remount_fs	= ceph_remount,

fs/ceph/super.h

@@ -854,6 +854,7 @@ static inline bool __ceph_have_pending_cap_snap(struct ceph_inode_info *ci)
 extern const struct inode_operations ceph_file_iops;
 
 extern struct inode *ceph_alloc_inode(struct super_block *sb);
+extern void ceph_evict_inode(struct inode *inode);
 extern void ceph_destroy_inode(struct inode *inode);
 extern int ceph_drop_inode(struct inode *inode);