ceph: track and report error of async metadata operation

Use errseq_t to track and report errors of async metadata operations,
similar to how kernel handles errors during writeback.

If any dirty caps or any unsafe request gets dropped during session
eviction, record -EIO in corresponding inode's i_meta_err. The error
will be reported by subsequent fsync,

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

1 files changed, 27 insertions, 13 deletions

diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 920e9f048bd8..df4bea231017 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -1270,6 +1270,7 @@ static void cleanup_session_requests(struct ceph_mds_client *mdsc,
 {
 	struct ceph_mds_request *req;
 	struct rb_node *p;
+	struct ceph_inode_info *ci;
 
 	dout("cleanup_session_requests mds%d\n", session->s_mds);
 	mutex_lock(&mdsc->mutex);
@@ -1278,6 +1279,16 @@ static void cleanup_session_requests(struct ceph_mds_client *mdsc,
 				       struct ceph_mds_request, r_unsafe_item);
 		pr_warn_ratelimited(" dropping unsafe request %llu\n",
 				    req->r_tid);
+		if (req->r_target_inode) {
+			/* dropping unsafe change of inode's attributes */
+			ci = ceph_inode(req->r_target_inode);
+			errseq_set(&ci->i_meta_err, -EIO);
+		}
+		if (req->r_unsafe_dir) {
+			/* dropping unsafe directory operation */
+			ci = ceph_inode(req->r_unsafe_dir);
+			errseq_set(&ci->i_meta_err, -EIO);
+		}
 		__unregister_request(mdsc, req);
 	}
 	/* zero r_attempts, so kick_requests() will re-send requests */
@@ -1370,7 +1381,7 @@ static int remove_session_caps_cb(struct inode *inode, struct ceph_cap *cap,
 	struct ceph_fs_client *fsc = (struct ceph_fs_client *)arg;
 	struct ceph_inode_info *ci = ceph_inode(inode);
 	LIST_HEAD(to_remove);
-	bool drop = false;
+	bool dirty_dropped = false;
 	bool invalidate = false;
 
 	dout("removing cap %p, ci is %p, inode is %p\n",
@@ -1405,7 +1416,7 @@ static int remove_session_caps_cb(struct inode *inode, struct ceph_cap *cap,
 				inode, ceph_ino(inode));
 			ci->i_dirty_caps = 0;
 			list_del_init(&ci->i_dirty_item);
-			drop = true;
+			dirty_dropped = true;
 		}
 		if (!list_empty(&ci->i_flushing_item)) {
 			pr_warn_ratelimited(
@@ -1415,10 +1426,22 @@ static int remove_session_caps_cb(struct inode *inode, struct ceph_cap *cap,
 			ci->i_flushing_caps = 0;
 			list_del_init(&ci->i_flushing_item);
 			mdsc->num_cap_flushing--;
-			drop = true;
+			dirty_dropped = true;
 		}
 		spin_unlock(&mdsc->cap_dirty_lock);
 
+		if (dirty_dropped) {
+			errseq_set(&ci->i_meta_err, -EIO);
+
+			if (ci->i_wrbuffer_ref_head == 0 &&
+			    ci->i_wr_ref == 0 &&
+			    ci->i_dirty_caps == 0 &&
+			    ci->i_flushing_caps == 0) {
+				ceph_put_snap_context(ci->i_head_snapc);
+				ci->i_head_snapc = NULL;
+			}
+		}
+
 		if (atomic_read(&ci->i_filelock_ref) > 0) {
 			/* make further file lock syscall return -EIO */
 			ci->i_ceph_flags |= CEPH_I_ERROR_FILELOCK;
@@ -1430,15 +1453,6 @@ static int remove_session_caps_cb(struct inode *inode, struct ceph_cap *cap,
 			list_add(&ci->i_prealloc_cap_flush->i_list, &to_remove);
 			ci->i_prealloc_cap_flush = NULL;
 		}
-
-               if (drop &&
-                  ci->i_wrbuffer_ref_head == 0 &&
-                  ci->i_wr_ref == 0 &&
-                  ci->i_dirty_caps == 0 &&
-                  ci->i_flushing_caps == 0) {
-                      ceph_put_snap_context(ci->i_head_snapc);
-                      ci->i_head_snapc = NULL;
-               }
 	}
 	spin_unlock(&ci->i_ceph_lock);
 	while (!list_empty(&to_remove)) {
@@ -1452,7 +1466,7 @@ static int remove_session_caps_cb(struct inode *inode, struct ceph_cap *cap,
 	wake_up_all(&ci->i_cap_wq);
 	if (invalidate)
 		ceph_queue_invalidate(inode);
-	if (drop)
+	if (dirty_dropped)
 		iput(inode);
 	return 0;
 }