X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=drivers%2Finfiniband%2Fhw%2Fmthca%2Fmthca_main.c;h=fb9f91b60f30e401cdb24aad39410db6aae0b0f3;hb=82638844d9a8581bbf33201cc209a14876eca167;hp=9ebadd6e0cfba4046e4dc7309aeaf4033cc0e18f;hpb=886c35fbcf6fb2eee15687efc2d64d99b6ad9a4a;p=pandora-kernel.git

diff --git a/drivers/infiniband/hw/mthca/mthca_main.c b/drivers/infiniband/hw/mthca/mthca_main.c
index 9ebadd6e0cfb..fb9f91b60f30 100644
--- a/drivers/infiniband/hw/mthca/mthca_main.c
+++ b/drivers/infiniband/hw/mthca/mthca_main.c
@@ -30,8 +30,6 @@
  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
- *
- * $Id: mthca_main.c 1396 2004-12-28 04:10:27Z roland $
  */
 
 #include <linux/module.h>
@@ -45,6 +43,7 @@
 #include "mthca_cmd.h"
 #include "mthca_profile.h"
 #include "mthca_memfree.h"
+#include "mthca_wqe.h"
 
 MODULE_AUTHOR("Roland Dreier");
 MODULE_DESCRIPTION("Mellanox InfiniBand HCA low-level driver");
@@ -200,7 +199,18 @@ static int mthca_dev_lim(struct mthca_dev *mdev, struct mthca_dev_lim *dev_lim)
 	mdev->limits.gid_table_len  	= dev_lim->max_gids;
 	mdev->limits.pkey_table_len 	= dev_lim->max_pkeys;
 	mdev->limits.local_ca_ack_delay = dev_lim->local_ca_ack_delay;
-	mdev->limits.max_sg             = dev_lim->max_sg;
+	/*
+	 * Need to allow for worst case send WQE overhead and check
+	 * whether max_desc_sz imposes a lower limit than max_sg; UD
+	 * send has the biggest overhead.
+	 */
+	mdev->limits.max_sg		= min_t(int, dev_lim->max_sg,
+					      (dev_lim->max_desc_sz -
+					       sizeof (struct mthca_next_seg) -
+					       (mthca_is_memfree(mdev) ?
+						sizeof (struct mthca_arbel_ud_seg) :
+						sizeof (struct mthca_tavor_ud_seg))) /
+						sizeof (struct mthca_data_seg));
 	mdev->limits.max_wqes           = dev_lim->max_qp_sz;
 	mdev->limits.max_qp_init_rdma   = dev_lim->max_requester_per_qp;
 	mdev->limits.reserved_qps       = dev_lim->reserved_qps;