Bluetooth: EWS: rewrite handling SAR bits
Andrei Emeltchenko [Tue, 11 Oct 2011 10:37:45 +0000 (13:37 +0300)]
Segmentation and Reassembly (SAR) occupies different windows in standard and
extended control fields. Convert hardcoded masks to relative ones and use shift
to access SAR bits.

Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>

include/net/bluetooth/l2cap.h
net/bluetooth/l2cap_core.c

index f24f5cf..0759ac6 100644 (file)
@@ -146,10 +146,10 @@ struct l2cap_conninfo {
 #define L2CAP_SUPER_SREJ       0x03
 
 /* L2CAP Segmentation and Reassembly */
-#define L2CAP_SDU_UNSEGMENTED       0x0000
-#define L2CAP_SDU_START             0x4000
-#define L2CAP_SDU_END               0x8000
-#define L2CAP_SDU_CONTINUE          0xC000
+#define L2CAP_SAR_UNSEGMENTED  0x00
+#define L2CAP_SAR_START                0x01
+#define L2CAP_SAR_END          0x02
+#define L2CAP_SAR_CONTINUE     0x03
 
 /* L2CAP Command rej. reasons */
 #define L2CAP_REJ_NOT_UNDERSTOOD       0x0000
@@ -516,7 +516,34 @@ static inline int l2cap_tx_window_full(struct l2cap_chan *ch)
 #define __get_reqseq(ctrl)     (((ctrl) & L2CAP_CTRL_REQSEQ) >> 8)
 #define __is_iframe(ctrl)      (!((ctrl) & L2CAP_CTRL_FRAME_TYPE))
 #define __is_sframe(ctrl)      ((ctrl) & L2CAP_CTRL_FRAME_TYPE)
-#define __is_sar_start(ctrl)   (((ctrl) & L2CAP_CTRL_SAR) == L2CAP_SDU_START)
+static inline __u8 __get_ctrl_sar(struct l2cap_chan *chan, __u32 ctrl)
+{
+       if (test_bit(FLAG_EXT_CTRL, &chan->flags))
+               return (ctrl & L2CAP_EXT_CTRL_SAR) >> L2CAP_EXT_CTRL_SAR_SHIFT;
+       else
+               return (ctrl & L2CAP_CTRL_SAR) >> L2CAP_CTRL_SAR_SHIFT;
+}
+
+static inline __u32 __set_ctrl_sar(struct l2cap_chan *chan, __u32 sar)
+{
+       if (test_bit(FLAG_EXT_CTRL, &chan->flags))
+               return (sar << L2CAP_EXT_CTRL_SAR_SHIFT) & L2CAP_EXT_CTRL_SAR;
+       else
+               return (sar << L2CAP_CTRL_SAR_SHIFT) & L2CAP_CTRL_SAR;
+}
+
+static inline bool __is_sar_start(struct l2cap_chan *chan, __u32 ctrl)
+{
+       return __get_ctrl_sar(chan, ctrl) == L2CAP_SAR_START;
+}
+
+static inline __u32 __get_sar_mask(struct l2cap_chan *chan)
+{
+       if (test_bit(FLAG_EXT_CTRL, &chan->flags))
+               return L2CAP_EXT_CTRL_SAR;
+       else
+               return L2CAP_CTRL_SAR;
+}
 
 static inline __u8 __get_ctrl_super(struct l2cap_chan *chan, __u32 ctrl)
 {
index 93b5da6..9ee42ba 100644 (file)
@@ -1311,7 +1311,7 @@ static void l2cap_retransmit_one_frame(struct l2cap_chan *chan, u8 tx_seq)
        tx_skb = skb_clone(skb, GFP_ATOMIC);
        bt_cb(skb)->retries++;
        control = get_unaligned_le16(tx_skb->data + L2CAP_HDR_SIZE);
-       control &= L2CAP_CTRL_SAR;
+       control &= __get_sar_mask(chan);
 
        if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
                control |= L2CAP_CTRL_FINAL;
@@ -1351,7 +1351,7 @@ static int l2cap_ertm_send(struct l2cap_chan *chan)
                bt_cb(skb)->retries++;
 
                control = get_unaligned_le16(tx_skb->data + L2CAP_HDR_SIZE);
-               control &= L2CAP_CTRL_SAR;
+               control &= __get_sar_mask(chan);
 
                if (test_and_clear_bit(CONN_SEND_FBIT, &chan->conn_state))
                        control |= L2CAP_CTRL_FINAL;
@@ -1582,7 +1582,7 @@ static int l2cap_sar_segment_sdu(struct l2cap_chan *chan, struct msghdr *msg, si
        size_t size = 0;
 
        skb_queue_head_init(&sar_queue);
-       control = L2CAP_SDU_START;
+       control = __set_ctrl_sar(chan, L2CAP_SAR_START);
        skb = l2cap_create_iframe_pdu(chan, msg, chan->remote_mps, control, len);
        if (IS_ERR(skb))
                return PTR_ERR(skb);
@@ -1595,10 +1595,10 @@ static int l2cap_sar_segment_sdu(struct l2cap_chan *chan, struct msghdr *msg, si
                size_t buflen;
 
                if (len > chan->remote_mps) {
-                       control = L2CAP_SDU_CONTINUE;
+                       control = __set_ctrl_sar(chan, L2CAP_SAR_CONTINUE);
                        buflen = chan->remote_mps;
                } else {
-                       control = L2CAP_SDU_END;
+                       control = __set_ctrl_sar(chan, L2CAP_SAR_END);
                        buflen = len;
                }
 
@@ -1654,7 +1654,7 @@ int l2cap_chan_send(struct l2cap_chan *chan, struct msghdr *msg, size_t len)
        case L2CAP_MODE_STREAMING:
                /* Entire SDU fits into one PDU */
                if (len <= chan->remote_mps) {
-                       control = L2CAP_SDU_UNSEGMENTED;
+                       control = __set_ctrl_sar(chan, L2CAP_SAR_UNSEGMENTED);
                        skb = l2cap_create_iframe_pdu(chan, msg, len, control,
                                                                        0);
                        if (IS_ERR(skb))
@@ -3201,15 +3201,15 @@ static int l2cap_reassemble_sdu(struct l2cap_chan *chan, struct sk_buff *skb, u1
 {
        int err = -EINVAL;
 
-       switch (control & L2CAP_CTRL_SAR) {
-       case L2CAP_SDU_UNSEGMENTED:
+       switch (__get_ctrl_sar(chan, control)) {
+       case L2CAP_SAR_UNSEGMENTED:
                if (chan->sdu)
                        break;
 
                err = chan->ops->recv(chan->data, skb);
                break;
 
-       case L2CAP_SDU_START:
+       case L2CAP_SAR_START:
                if (chan->sdu)
                        break;
 
@@ -3231,7 +3231,7 @@ static int l2cap_reassemble_sdu(struct l2cap_chan *chan, struct sk_buff *skb, u1
                err = 0;
                break;
 
-       case L2CAP_SDU_CONTINUE:
+       case L2CAP_SAR_CONTINUE:
                if (!chan->sdu)
                        break;
 
@@ -3245,7 +3245,7 @@ static int l2cap_reassemble_sdu(struct l2cap_chan *chan, struct sk_buff *skb, u1
                err = 0;
                break;
 
-       case L2CAP_SDU_END:
+       case L2CAP_SAR_END:
                if (!chan->sdu)
                        break;
 
@@ -3343,7 +3343,7 @@ static void l2cap_check_srej_gap(struct l2cap_chan *chan, u8 tx_seq)
                        break;
 
                skb = skb_dequeue(&chan->srej_q);
-               control = bt_cb(skb)->sar << L2CAP_CTRL_SAR_SHIFT;
+               control = __set_ctrl_sar(chan, bt_cb(skb)->sar);
                err = l2cap_reassemble_sdu(chan, skb, control);
 
                if (err < 0) {
@@ -3398,7 +3398,7 @@ static inline int l2cap_data_channel_iframe(struct l2cap_chan *chan, u16 rx_cont
 {
        u8 tx_seq = __get_txseq(rx_control);
        u8 req_seq = __get_reqseq(rx_control);
-       u8 sar = rx_control >> L2CAP_CTRL_SAR_SHIFT;
+       u8 sar = __get_ctrl_sar(chan, rx_control);
        int tx_seq_offset, expected_tx_seq_offset;
        int num_to_ack = (chan->tx_win/6) + 1;
        int err = 0;
@@ -3707,7 +3707,7 @@ static int l2cap_ertm_data_rcv(struct sock *sk, struct sk_buff *skb)
        if (l2cap_check_fcs(chan, skb))
                goto drop;
 
-       if (__is_sar_start(control) && __is_iframe(control))
+       if (__is_sar_start(chan, control) && __is_iframe(control))
                len -= 2;
 
        if (chan->fcs == L2CAP_FCS_CRC16)
@@ -3811,7 +3811,7 @@ static inline int l2cap_data_channel(struct l2cap_conn *conn, u16 cid, struct sk
                if (l2cap_check_fcs(chan, skb))
                        goto drop;
 
-               if (__is_sar_start(control))
+               if (__is_sar_start(chan, control))
                        len -= 2;
 
                if (chan->fcs == L2CAP_FCS_CRC16)