[PATCH AUTOSEL 4.19 25/45] ibmvnic: Unmap DMA address of TX descriptor buffers after use
From: Sasha Levin <sashal@kernel.org>
Date: 2019-08-29 18:16:33
Also in:
linuxppc-dev, lkml, stable
Subsystem:
ibm power sriov virtual nic device driver, linux for powerpc (32-bit and 64-bit), networking drivers, the rest · Maintainers:
Haren Myneni, Rick Lindsley, Madhavan Srinivasan, Michael Ellerman, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
From: Thomas Falcon <redacted> [ Upstream commit 80f0fe0934cd3daa13a5e4d48a103f469115b160 ] There's no need to wait until a completion is received to unmap TX descriptor buffers that have been passed to the hypervisor. Instead unmap it when the hypervisor call has completed. This patch avoids the possibility that a buffer will not be unmapped because a TX completion is lost or mishandled. Reported-by: Abdul Haleem <redacted> Tested-by: Devesh K. Singh <redacted> Signed-off-by: Thomas Falcon <redacted> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> --- drivers/net/ethernet/ibm/ibmvnic.c | 11 ++--------- 1 file changed, 2 insertions(+), 9 deletions(-)
diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
index 0ae43d27cdcff..255de7d68cd33 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c@@ -1586,6 +1586,8 @@ static int ibmvnic_xmit(struct sk_buff *skb, struct net_device *netdev) lpar_rc = send_subcrq_indirect(adapter, handle_array[queue_num], (u64)tx_buff->indir_dma, (u64)num_entries); + dma_unmap_single(dev, tx_buff->indir_dma, + sizeof(tx_buff->indir_arr), DMA_TO_DEVICE); } else { tx_buff->num_entries = num_entries; lpar_rc = send_subcrq(adapter, handle_array[queue_num],
@@ -2747,7 +2749,6 @@ static int ibmvnic_complete_tx(struct ibmvnic_adapter *adapter, union sub_crq *next; int index; int i, j; - u8 *first; restart_loop: while (pending_scrq(adapter, scrq)) {
@@ -2777,14 +2778,6 @@ static int ibmvnic_complete_tx(struct ibmvnic_adapter *adapter, txbuff->data_dma[j] = 0; } - /* if sub_crq was sent indirectly */ - first = &txbuff->indir_arr[0].generic.first; - if (*first == IBMVNIC_CRQ_CMD) { - dma_unmap_single(dev, txbuff->indir_dma, - sizeof(txbuff->indir_arr), - DMA_TO_DEVICE); - *first = 0; - } if (txbuff->last_frag) { dev_kfree_skb_any(txbuff->skb);
--
2.20.1