wimax/i2400m: limit the message size upto 16KiB [v1]

According to Intel Wimax i3200, i5x50 and i6x50 specification
documents, the maximum size of each TX message can be upto 16KiB.
This patch modifies the i2400m_tx() routine to check that the
message size does not exceed the 16KiB limit.
Please refer the documentation in the code for details.

Signed-off-by: Prasanna S. Panchamukhi <prasannax.s.panchamukhi@intel.com>

diff --git a/drivers/net/wimax/i2400m/tx.c b/drivers/net/wimax/i2400m/tx.c
index b10c3b77c27e312885db7a7fc59ce9515a0e169b..a5002c8467c20f122356bee396991836143eae17 100644 (file)
--- a/drivers/net/wimax/i2400m/tx.c
+++ b/drivers/net/wimax/i2400m/tx.c
@@ -282,6 +282,11 @@ enum {
        I2400M_TX_PLD_SIZE = sizeof(struct i2400m_msg_hdr)
        + I2400M_TX_PLD_MAX * sizeof(struct i2400m_pld),
        I2400M_TX_SKIP = 0x80000000,
+       /*
+        * According to Intel Wimax i3200, i5x50 and i6x50 specification
+        * documents, the maximum size of each message can be up to 16KiB.
+        */
+       I2400M_TX_MSG_SIZE = 16384,
        /*
         * 16 byte aligned MAX_MTU + 4 byte payload prefix.
         */
@@ -682,7 +687,13 @@ try_new:
        }
        if (i2400m->tx_msg == NULL)
                goto error_tx_new;
-       if (i2400m->tx_msg->size + padded_len > I2400M_TX_BUF_SIZE / 2) {
+       /*
+        * Check if this skb will fit in the TX queue's current active
+        * TX message. The total message size must not exceed the maximum
+        * size of each message I2400M_TX_MSG_SIZE. If it exceeds,
+        * close the current message and push this skb into the new message.
+        */
+       if (i2400m->tx_msg->size + padded_len > I2400M_TX_MSG_SIZE) {
                d_printf(2, dev, "TX: message too big, going new\n");
                i2400m_tx_close(i2400m);
                i2400m_tx_new(i2400m);