[PATCH] Better fixup for the orinoco driver

The latest kernel added a pretty ugly fix for the orinoco etherleak bug
which contains bogus skb->len checks already done by the caller and causes
copies of all odd sized frames (which are quite common)

While the skb->len check should be ripped out the other fix is harder to do
properly so I'm proposing for this the -mm tree only until next 2.6.x so
that it gets tested.

Instead of copying buffers around blindly this code implements a padding
aware version of the hermes buffer writing function which does padding as
the buffer is loaded and thus more cleanly and without bogus 1.5K copies.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>

1 files changed, 38 insertions, 0 deletions

diff --git a/drivers/net/wireless/hermes.c b/drivers/net/wireless/hermes.c
index eba0d9d2b7c5..579480dad374 100644
--- a/drivers/net/wireless/hermes.c
+++ b/drivers/net/wireless/hermes.c
@@ -444,6 +444,43 @@ int hermes_bap_pwrite(hermes_t *hw, int bap, const void *buf, unsigned len,
         return err;
 }
 
+/* Write a block of data to the chip's buffer with padding if
+ * neccessary, via the BAP. Synchronization/serialization is the
+ * caller's problem. len must be even.
+ *
+ * Returns: < 0 on internal failure (errno), 0 on success, > 0 on error from firmware
+ */
+int hermes_bap_pwrite_pad(hermes_t *hw, int bap, const void *buf, unsigned data_len, unsigned len,
+                      u16 id, u16 offset)
+{
+        int dreg = bap ? HERMES_DATA1 : HERMES_DATA0;
+        int err = 0;
+
+        if (len < 0 || len % 2 || data_len > len)
+                return -EINVAL;
+
+        err = hermes_bap_seek(hw, bap, id, offset);
+        if (err)
+                goto out;
+
+        /* Transfer all the complete words of data */
+        hermes_write_words(hw, dreg, buf, data_len/2);
+        /* If there is an odd byte left over pad and transfer it */
+        if (data_len & 1) {
+                u8 end[2];
+                end[1] = 0;
+                end[0] = ((unsigned char *)buf)[data_len - 1];
+                hermes_write_words(hw, dreg, end, 1);
+                data_len ++;
+        }
+        /* Now send zeros for the padding */
+        if (data_len < len)
+                hermes_clear_words(hw, dreg, (len - data_len) / 2);
+        /* Complete */
+ out:
+        return err;
+}
+
 /* Read a Length-Type-Value record from the card.
  *
  * If length is NULL, we ignore the length read from the card, and
@@ -531,6 +568,7 @@ EXPORT_SYMBOL(hermes_allocate);
 
 EXPORT_SYMBOL(hermes_bap_pread);
 EXPORT_SYMBOL(hermes_bap_pwrite);
+EXPORT_SYMBOL(hermes_bap_pwrite_pad);
 EXPORT_SYMBOL(hermes_read_ltv);
 EXPORT_SYMBOL(hermes_write_ltv);