Hi Ulisses,
On Mon, Feb 13, 2012 at 10:58:43AM +0200, Emeltchenko Andrei wrote:
> Hi Ulisses,
>
> On Fri, Feb 10, 2012 at 04:24:57PM -0200, Ulisses Furquim wrote:
> > Hi Andrei,
> >
> > On Fri, Feb 10, 2012 at 11:54 AM, Emeltchenko Andrei
> > <Andrei.Emeltchenko.news@xxxxxxxxx> wrote:
> > > From: Andrei Emeltchenko <andrei.emeltchenko@xxxxxxxxx>
> > >
> > > Usage of RCU list looks not reasonalbe for a number of reasons:
> > > our code sleep and we have to use socket spinlocks, some parts
> > > of code are updaters thus we need to use mutexes anyway.
> > >
> > > Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@xxxxxxxxx>
> >
> > No need to lock and unlock conn->chan_lock in l2cap_disconnect_rsp()?
> > This change from RCU to mutexes really should be just one commit IMO.
>
> I try to add chunks which are not in different patches but then this patch
> would several hundreds lines long. If this OK I just merge them.
I've picked chunks which might come after this patch that are dealing with
locking conn->chan_lock. Please check it below. Do you think it needs to
be merged with "RCU remove" patch?
diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
index c0a35c5..356ce6e 100644
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -240,11 +240,13 @@ static void l2cap_chan_timeout(struct work_struct
*work)
{
struct l2cap_chan *chan = container_of(work, struct l2cap_chan,
chan_timer.work);
+ struct l2cap_conn *conn = chan->conn;
struct sock *sk = chan->sk;
int reason;
BT_DBG("chan %p state %d", chan, chan->state);
+ mutex_lock(&conn->chan_lock);
lock_sock(sk);
if (chan->state == BT_CONNECTED || chan->state == BT_CONFIG)
@@ -258,6 +260,7 @@ static void l2cap_chan_timeout(struct work_struct
*work)
l2cap_chan_close(chan, reason);
release_sock(sk);
+ mutex_unlock(&conn->chan_lock);
chan->ops->close(chan->data);
l2cap_chan_put(chan);
@@ -2619,6 +2622,7 @@ static inline int l2cap_connect_req(struct
l2cap_conn *conn, struct l2cap_cmd_hd
parent = pchan->sk;
+ mutex_lock(&conn->chan_lock);
lock_sock(parent);
/* Check if the ACL is secure enough (if not SDP) */
@@ -2692,6 +2696,7 @@ static inline int l2cap_connect_req(struct
l2cap_conn *conn, struct l2cap_cmd_hd
response:
release_sock(parent);
+ mutex_unlock(&conn->chan_lock);
sendresp:
rsp.scid = cpu_to_le16(scid);
@@ -2733,6 +2738,7 @@ static inline int l2cap_connect_rsp(struct
l2cap_conn *conn, struct l2cap_cmd_hd
struct l2cap_chan *chan;
struct sock *sk;
u8 req[128];
+ int err;
scid = __le16_to_cpu(rsp->scid);
dcid = __le16_to_cpu(rsp->dcid);
@@ -2742,16 +2748,24 @@ static inline int l2cap_connect_rsp(struct
l2cap_conn *conn, struct l2cap_cmd_hd
BT_DBG("dcid 0x%4.4x scid 0x%4.4x result 0x%2.2x status 0x%2.2x",
dcid, scid, result,
status);
+ mutex_lock(&conn->chan_lock);
+
if (scid) {
- chan = l2cap_get_chan_by_scid(conn, scid);
- if (!chan)
- return -EFAULT;
+ chan = __l2cap_get_chan_by_scid(conn, scid);
+ if (!chan) {
+ err = -EFAULT;
+ goto unlock;
+ }
} else {
- chan = l2cap_get_chan_by_ident(conn, cmd->ident);
- if (!chan)
- return -EFAULT;
+ chan = __l2cap_get_chan_by_ident(conn, cmd->ident);
+ if (!chan) {
+ err = -EFAULT;
+ goto unlock;
+ }
}
+ err = 0;
+
sk = chan->sk;
switch (result) {
@@ -2779,7 +2793,10 @@ static inline int l2cap_connect_rsp(struct
l2cap_conn *conn, struct l2cap_cmd_hd
}
release_sock(sk);
- return 0;
+unlock:
+ mutex_unlock(&conn->chan_lock);
+
+ return err;
}
static inline void set_default_fcs(struct l2cap_chan *chan)
@@ -3025,9 +3042,13 @@ static inline int l2cap_disconnect_req(struct
l2cap_conn *conn, struct l2cap_cmd
BT_DBG("scid 0x%4.4x dcid 0x%4.4x", scid, dcid);
- chan = l2cap_get_chan_by_scid(conn, dcid);
- if (!chan)
+ mutex_lock(&conn->chan_lock);
+
+ chan = __l2cap_get_chan_by_scid(conn, dcid);
+ if (!chan) {
+ mutex_unlock(&conn->chan_lock);
return 0;
+ }
sk = chan->sk;
@@ -3039,6 +3060,7 @@ static inline int l2cap_disconnect_req(struct
l2cap_conn *conn, struct l2cap_cmd
l2cap_chan_del(chan, ECONNRESET);
release_sock(sk);
+ mutex_unlock(&conn->chan_lock);
chan->ops->close(chan->data);
return 0;
@@ -3056,14 +3078,19 @@ static inline int l2cap_disconnect_rsp(struct
l2cap_conn *conn, struct l2cap_cmd
BT_DBG("dcid 0x%4.4x scid 0x%4.4x", dcid, scid);
- chan = l2cap_get_chan_by_scid(conn, scid);
- if (!chan)
+ mutex_lock(&conn->chan_lock);
+
+ chan = __l2cap_get_chan_by_scid(conn, scid);
+ if (!chan) {
+ mutex_unlock(&conn->chan_lock);
return 0;
+ }
sk = chan->sk;
l2cap_chan_del(chan, 0);
release_sock(sk);
+ mutex_unlock(&conn->chan_lock);
chan->ops->close(chan->data);
return 0;
--
1.7.8.3
Best regards
Andrei Emeltchenko
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