NFSv4: Fix a reboot recovery race when opening a file
If the server reboots after it has replied to our OPEN, but before we
call nfs4_opendata_to_nfs4_state(), then the reboot recovery thread
will not see a stateid for this open, and so will fail to recover it.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index d512273..7cbf7aa 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -1848,6 +1848,43 @@
sattr->ia_valid |= ATTR_MTIME;
}
+static int _nfs4_open_and_get_state(struct nfs4_opendata *opendata,
+ fmode_t fmode,
+ int flags,
+ struct nfs4_state **res)
+{
+ struct nfs4_state_owner *sp = opendata->owner;
+ struct nfs_server *server = sp->so_server;
+ struct nfs4_state *state;
+ unsigned int seq;
+ int ret;
+
+ seq = raw_seqcount_begin(&sp->so_reclaim_seqcount);
+
+ ret = _nfs4_proc_open(opendata);
+ if (ret != 0)
+ goto out;
+
+ state = nfs4_opendata_to_nfs4_state(opendata);
+ ret = PTR_ERR(state);
+ if (IS_ERR(state))
+ goto out;
+ if (server->caps & NFS_CAP_POSIX_LOCK)
+ set_bit(NFS_STATE_POSIX_LOCKS, &state->flags);
+
+ ret = nfs4_opendata_access(sp->so_cred, opendata, state, fmode, flags);
+ if (ret != 0)
+ goto out;
+
+ if (read_seqcount_retry(&sp->so_reclaim_seqcount, seq)) {
+ nfs4_schedule_stateid_recovery(server, state);
+ nfs4_wait_clnt_recover(server->nfs_client);
+ }
+ *res = state;
+out:
+ return ret;
+}
+
/*
* Returns a referenced nfs4_state
*/
@@ -1892,18 +1929,7 @@
if (dentry->d_inode != NULL)
opendata->state = nfs4_get_open_state(dentry->d_inode, sp);
- status = _nfs4_proc_open(opendata);
- if (status != 0)
- goto err_opendata_put;
-
- state = nfs4_opendata_to_nfs4_state(opendata);
- status = PTR_ERR(state);
- if (IS_ERR(state))
- goto err_opendata_put;
- if (server->caps & NFS_CAP_POSIX_LOCK)
- set_bit(NFS_STATE_POSIX_LOCKS, &state->flags);
-
- status = nfs4_opendata_access(cred, opendata, state, fmode, flags);
+ status = _nfs4_open_and_get_state(opendata, fmode, flags, &state);
if (status != 0)
goto err_opendata_put;