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 <ericvh@gmail.com>
This commit is contained in:
Eric Van Hensbergen 2008-10-17 12:45:40 -05:00
parent f0a0ac2ee5
commit 7eb923b80c
1 changed files with 17 additions and 7 deletions

View File

@ -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;
}
/**