ioat3: fix p-disabled q-continuation

[safe/jmp/linux-2.6] / drivers / dma / ioat / dma_v3.c

diff --git a/drivers/dma/ioat/dma_v3.c b/drivers/dma/ioat/dma_v3.c
index 42f6f10..e58ecb2 100644 (file)
--- a/drivers/dma/ioat/dma_v3.c
+++ b/drivers/dma/ioat/dma_v3.c
@@ -650,9 +650,11 @@ __ioat3_prep_pq_lock(struct dma_chan *c, enum sum_check_flags *result,
 
        num_descs = ioat2_xferlen_to_descs(ioat, len);
        /* we need 2x the number of descriptors to cover greater than 3
-        * sources
+        * sources (we need 1 extra source in the q-only continuation
+        * case and 3 extra sources in the p+q continuation case.
         */
-       if (src_cnt > 3 || flags & DMA_PREP_CONTINUE) {
+       if (src_cnt + dmaf_p_disabled_continue(flags) > 3 ||
+           (dmaf_continue(flags) && !dmaf_p_disabled_continue(flags))) {
                with_ext = 1;
                num_descs *= 2;
        } else