usb: gadget: rndis: don't use dev_get_stats

Since 2.6.36, spin_lock_bh has been added to dev_txq_stats_fold. So
dev_get_stats cannot be called from atomic context.

Replaced it by netdev_stats_to_stats64 to copy the stats directly. This
will work if the device driver does not need txq tx stats folding.

http://lkml.org/lkml/2010/9/20/250

Change-Id: I715b00892beda56cc369139d6e2bdc9efb6bfe79
Signed-off-by: Benoit Goby <benoit@android.com>

diff --git a/drivers/usb/gadget/rndis.c b/drivers/usb/gadget/rndis.c
index d3cdffea9c8a33e71dd8fb5bacaf41c7aaf240cd..6cea2e17b32b2d56adb32d4a8ddfde025d9a1f75 100644 (file)
--- a/drivers/usb/gadget/rndis.c
+++ b/drivers/usb/gadget/rndis.c
@@ -159,6 +159,25 @@ static const u32 oid_supported_list[] =
 #endif /* RNDIS_PM */
 };
 
+/* HACK: copied from net/core/dev.c to replace dev_get_stats since
+ * dev_get_stats cannot be called from atomic context */
+static void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
+                                   const struct net_device_stats *netdev_stats)
+{
+#if BITS_PER_LONG == 64
+       BUILD_BUG_ON(sizeof(*stats64) != sizeof(*netdev_stats));
+       memcpy(stats64, netdev_stats, sizeof(*stats64));
+#else
+       size_t i, n = sizeof(*stats64) / sizeof(u64);
+       const unsigned long *src = (const unsigned long *)netdev_stats;
+       u64 *dst = (u64 *)stats64;
+
+       BUILD_BUG_ON(sizeof(*netdev_stats) / sizeof(unsigned long) !=
+                    sizeof(*stats64) / sizeof(u64));
+       for (i = 0; i < n; i++)
+               dst[i] = src[i];
+#endif
+}
 
 /* NDIS Functions */
 static int gen_ndis_query_resp(int configNr, u32 OID, u8 *buf,
@@ -171,7 +190,7 @@ static int gen_ndis_query_resp(int configNr, u32 OID, u8 *buf,
        rndis_query_cmplt_type *resp;
        struct net_device *net;
        struct rtnl_link_stats64 temp;
-       const struct rtnl_link_stats64 *stats;
+       struct rtnl_link_stats64 *stats = &temp;
 
        if (!r) return -ENOMEM;
        resp = (rndis_query_cmplt_type *)r->buf;
@@ -194,7 +213,7 @@ static int gen_ndis_query_resp(int configNr, u32 OID, u8 *buf,
        resp->InformationBufferOffset = cpu_to_le32(16);
 
        net = rndis_per_dev_params[configNr].dev;
-       stats = dev_get_stats(net, &temp);
+       netdev_stats_to_stats64(stats, &net->stats);
 
        switch (OID) {