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>

1 files changed, 12 insertions, 1 deletions

diff --git a/drivers/net/wimax/i2400m/tx.c b/drivers/net/wimax/i2400m/tx.c
index b10c3b77c27e..a5002c8467c2 100644
--- a/drivers/net/wimax/i2400m/tx.c
+++ b/drivers/net/wimax/i2400m/tx.c
@@ -283,6 +283,11 @@ enum {
         + 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.
          */
         I2400M_MAX_MTU_ALIGN = 16,
@@ -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);