From 7eb923b80c8ce16697129fb2dcdfaeabf83f0dbc Mon Sep 17 00:00:00 2001 From: Eric Van Hensbergen Date: Fri, 17 Oct 2008 12:45:40 -0500 Subject: [PATCH] 9p: add more conservative locking During the reorganization some of the multi-theaded locking assumptions were accidently relaxed. This patch moves us back towards a more conservative locking strategy. Signed-off-by: Eric Van Hensbergen --- net/9p/trans_fd.c | 24 +++++++++++++++++------- 1 file changed, 17 insertions(+), 7 deletions(-) diff --git a/net/9p/trans_fd.c b/net/9p/trans_fd.c index e8ebe2cb7e8b..be65d8242fd2 100644 --- a/net/9p/trans_fd.c +++ b/net/9p/trans_fd.c @@ -188,8 +188,16 @@ static void p9_conn_cancel(struct p9_conn *m, int err) LIST_HEAD(cancel_list); P9_DPRINTK(P9_DEBUG_ERROR, "mux %p err %d\n", m, err); - m->err = err; + spin_lock_irqsave(&m->client->lock, flags); + + if (m->err) { + spin_unlock_irqrestore(&m->client->lock, flags); + return; + } + + m->err = err; + list_for_each_entry_safe(req, rtmp, &m->req_list, req_list) { req->status = REQ_STATUS_ERROR; if (!req->t_err) @@ -352,8 +360,9 @@ static void p9_read_work(struct work_struct *work) /* not an else because some packets (like clunk) have no payload */ if ((m->req) && (m->rpos == m->rsize)) { /* packet is read in */ P9_DPRINTK(P9_DEBUG_TRANS, "got new packet\n"); - + spin_lock(&m->client->lock); list_del(&m->req->req_list); + spin_unlock(&m->client->lock); p9_client_cb(m->client, m->req); m->rbuf = NULL; @@ -651,9 +660,8 @@ static int p9_fd_request(struct p9_client *client, struct p9_req_t *req) if (m->err < 0) return m->err; - req->status = REQ_STATUS_UNSENT; - spin_lock(&client->lock); + req->status = REQ_STATUS_UNSENT; list_add_tail(&req->req_list, &m->unsent_req_list); spin_unlock(&client->lock); @@ -672,19 +680,21 @@ static int p9_fd_cancel(struct p9_client *client, struct p9_req_t *req) { struct p9_trans_fd *ts = client->trans; struct p9_conn *m = ts->conn; + int ret = 1; P9_DPRINTK(P9_DEBUG_TRANS, "mux %p req %p\n", m, req); spin_lock(&client->lock); list_del(&req->req_list); - spin_unlock(&client->lock); if (req->status == REQ_STATUS_UNSENT) { req->status = REQ_STATUS_FLSHD; - return 0; + ret = 0; } - return 1; + spin_unlock(&client->lock); + + return ret; } /** -- 2.39.5