ceph: prepopulate inodes only when request is aborted

If r_aborted is true, we do not hold the dir i_mutex, and cannot touch
the dcache.  However, we still need to update the inodes with the state
returned by the MDS.

Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sage Weil <sage@inktank.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 38 insertions, 2 deletions

diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index 2971eaa65cdc..4bc086a72475 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -1130,8 +1130,8 @@ int ceph_fill_trace(struct super_block *sb, struct ceph_mds_request *req,
                                             req->r_request_started);
                 dout(" final dn %p\n", dn);
                 i++;
-        } else if (req->r_op == CEPH_MDS_OP_LOOKUPSNAP ||
-                   req->r_op == CEPH_MDS_OP_MKSNAP) {
+        } else if ((req->r_op == CEPH_MDS_OP_LOOKUPSNAP ||
+                   req->r_op == CEPH_MDS_OP_MKSNAP) && !req->r_aborted) {
                 struct dentry *dn = req->r_dentry;
 
                 /* fill out a snapdir LOOKUPSNAP dentry */
@@ -1195,6 +1195,39 @@ done:
 /*
  * Prepopulate our cache with readdir results, leases, etc.
  */
+static int readdir_prepopulate_inodes_only(struct ceph_mds_request *req,
+                                           struct ceph_mds_session *session)
+{
+        struct ceph_mds_reply_info_parsed *rinfo = &req->r_reply_info;
+        int i, err = 0;
+
+        for (i = 0; i < rinfo->dir_nr; i++) {
+                struct ceph_vino vino;
+                struct inode *in;
+                int rc;
+
+                vino.ino = le64_to_cpu(rinfo->dir_in[i].in->ino);
+                vino.snap = le64_to_cpu(rinfo->dir_in[i].in->snapid);
+
+                in = ceph_get_inode(req->r_dentry->d_sb, vino);
+                if (IS_ERR(in)) {
+                        err = PTR_ERR(in);
+                        dout("new_inode badness got %d\n", err);
+                        continue;
+                }
+                rc = fill_inode(in, &rinfo->dir_in[i], NULL, session,
+                                req->r_request_started, -1,
+                                &req->r_caps_reservation);
+                if (rc < 0) {
+                        pr_err("fill_inode badness on %p got %d\n", in, rc);
+                        err = rc;
+                        continue;
+                }
+        }
+
+        return err;
+}
+
 int ceph_readdir_prepopulate(struct ceph_mds_request *req,
                              struct ceph_mds_session *session)
 {
@@ -1209,6 +1242,9 @@ int ceph_readdir_prepopulate(struct ceph_mds_request *req,
         u64 frag = le32_to_cpu(rhead->args.readdir.frag);
         struct ceph_dentry_info *di;
 
+        if (req->r_aborted)
+                return readdir_prepopulate_inodes_only(req, session);
+
         if (le32_to_cpu(rinfo->head->op) == CEPH_MDS_OP_LSSNAP) {
                 snapdir = ceph_get_snapdir(parent->d_inode);
                 parent = d_find_alias(snapdir);