Re: [RFCv1 2/3] Bluetooth: Simplify num_comp_pkts_evt function

[Emeltchenko Andrei <Andrei.Emeltchenko.news@gmail.com>]

Hi Marcel,

On Mon, Dec 05, 2011 at 02:51:34PM +0100, Marcel Holtmann wrote:
> Hi Andrei,
> 
> > Simplify function and remove fourth level of indentation.
> > 
> > Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
> > ---
> >  net/bluetooth/hci_event.c |   43 +++++++++++++++++++++++++------------------
> >  1 files changed, 25 insertions(+), 18 deletions(-)
> > 
> > diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
> > index 273e1cb..fd7e6b5 100644
> > --- a/net/bluetooth/hci_event.c
> > +++ b/net/bluetooth/hci_event.c
> > @@ -2288,28 +2288,35 @@ static inline void hci_num_comp_pkts_evt(struct hci_dev *hdev, struct sk_buff *s
> >  		count  = get_unaligned_le16(ptr++);
> 
> actually we first need a cleanup of this function. This part is
> horrible. It works because of our ptr cast to uint16, but we should
> actually use a proper struct here. Maybe an info struct like we use for
> inquiry result might be helpful here.

Something like the code below?

diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index e33e468..403974c 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -1018,9 +1018,14 @@ struct hci_ev_role_change {
 } __packed;
 
 #define HCI_EV_NUM_COMP_PKTS           0x13
+struct hci_comp_pkts_info {
+       __le16   handle;
+       __le16   count;
+} __packed;
+
 struct hci_ev_num_comp_pkts {
        __u8     num_hndl;
-       /* variable length part */
+       struct hci_comp_pkts_info handles[0];
 } __packed;
 
 #define HCI_EV_MODE_CHANGE             0x14
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 238fb65..079b94f 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -2273,26 +2273,27 @@ static inline void hci_role_change_evt(struct
hci_dev *hdev, struct sk_buff *skb
 static inline void hci_num_comp_pkts_evt(struct hci_dev *hdev, struct
sk_buff *skb)
 {
        struct hci_ev_num_comp_pkts *ev = (void *) skb->data;
-       __le16 *ptr;
+       struct hci_comp_pkts_info *info;
        int i;
 
        skb_pull(skb, sizeof(*ev));
 
        BT_DBG("%s num_hndl %d", hdev->name, ev->num_hndl);
 
-       if (skb->len < ev->num_hndl * 4) {
+       if (skb->len < ev->num_hndl * sizeof(*info)) {
                BT_DBG("%s bad parameters", hdev->name);
                return;
        }
 
        tasklet_disable(&hdev->tx_task);
 
-       for (i = 0, ptr = (__le16 *) skb->data; i < ev->num_hndl; i++) {
+       for (i = 0; i < ev->num_hndl; i++) {
                struct hci_conn *conn;
                __u16  handle, count;
 
-               handle = get_unaligned_le16(ptr++);
-               count  = get_unaligned_le16(ptr++);
+               info = &ev->handles[i];
+               handle = __le16_to_cpu(info->handle);
+               count  = __le16_to_cpu(info->count);
 
                conn = hci_conn_hash_lookup_handle(hdev, handle);
                if (!conn)



> It also needs a check that we are in packet based flow control. If not,
> we need to just ignore this event and print an error message.

will add.

> 
> >  		conn = hci_conn_hash_lookup_handle(hdev, handle);
> > -		if (conn) {
> > -			conn->sent -= count;
> > -
> > -			if (conn->type == ACL_LINK) {
> > +		if (!conn)
> > +			continue;
> > +
> > +		conn->sent -= count;
> > +
> > +		switch (conn->type) {
> > +		case ACL_LINK:
> > +			hdev->acl_cnt += count;
> > +			if (hdev->acl_cnt > hdev->acl_pkts)
> > +				hdev->acl_cnt = hdev->acl_pkts;
> > +			break;
> > +
> > +		case LE_LINK:
> > +			if (hdev->le_pkts) {
> > +				hdev->le_cnt += count;
> > +				if (hdev->le_cnt > hdev->le_pkts)
> > +					hdev->le_cnt = hdev->le_pkts;
> > +			} else {
> >  				hdev->acl_cnt += count;
> >  				if (hdev->acl_cnt > hdev->acl_pkts)
> >  					hdev->acl_cnt = hdev->acl_pkts;
> > -			} else if (conn->type == LE_LINK) {
> > -				if (hdev->le_pkts) {
> > -					hdev->le_cnt += count;
> > -					if (hdev->le_cnt > hdev->le_pkts)
> > -						hdev->le_cnt = hdev->le_pkts;
> > -				} else {
> > -					hdev->acl_cnt += count;
> > -					if (hdev->acl_cnt > hdev->acl_pkts)
> > -						hdev->acl_cnt = hdev->acl_pkts;
> > -				}
> > -			} else {
> > -				hdev->sco_cnt += count;
> > -				if (hdev->sco_cnt > hdev->sco_pkts)
> > -					hdev->sco_cnt = hdev->sco_pkts;
> >  			}
> > +			break;
> > +
> > +		default:
> > +			hdev->sco_cnt += count;
> > +			if (hdev->sco_cnt > hdev->sco_pkts)
> > +				hdev->sco_cnt = hdev->sco_pkts;
> > +			break;
> 
> And this should be under SCO_LINK and default should print an error.

will fix

Best regards 
Andrei Emeltchenko