9p: add bdi backing to mount session

This ensures that dirty data gets flushed properly.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/fs/9p/v9fs.c b/fs/9p/v9fs.c
index 5c5bc8480070..f8b86e92cd66 100644
--- a/fs/9p/v9fs.c
+++ b/fs/9p/v9fs.c
@@ -238,6 +238,13 @@ struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
                 return ERR_PTR(-ENOMEM);
         }
 
+        rc = bdi_setup_and_register(&v9ses->bdi, "9p", BDI_CAP_MAP_COPY);
+        if (rc) {
+                __putname(v9ses->aname);
+                __putname(v9ses->uname);
+                return ERR_PTR(rc);
+        }
+
         spin_lock(&v9fs_sessionlist_lock);
         list_add(&v9ses->slist, &v9fs_sessionlist);
         spin_unlock(&v9fs_sessionlist_lock);
@@ -301,6 +308,7 @@ struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
         return fid;
 
 error:
+        bdi_destroy(&v9ses->bdi);
         return ERR_PTR(retval);
 }
 
@@ -326,6 +334,8 @@ void v9fs_session_close(struct v9fs_session_info *v9ses)
         __putname(v9ses->uname);
         __putname(v9ses->aname);
 
+        bdi_destroy(&v9ses->bdi);
+
         spin_lock(&v9fs_sessionlist_lock);
         list_del(&v9ses->slist);
         spin_unlock(&v9fs_sessionlist_lock);