From: Thomas Falcon <tlfalcon@linux.ibm.com>
To: netdev@vger.kernel.org
Cc: Thomas Falcon <tlfalcon@linux.ibm.com>
Subject: [PATCH net] ibmvnic: Unmap DMA address of TX descriptor buffers after use
Date: Wed, 14 Aug 2019 14:57:05 -0500 [thread overview]
Message-ID: <1565812625-24364-1-git-send-email-tlfalcon@linux.ibm.com> (raw)
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 <abdhalee@linux.vnet.ibm.com>
Tested-by: Devesh K. Singh <devesh_singh@in.ibm.com>
Signed-off-by: Thomas Falcon <tlfalcon@linux.ibm.com>
---
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 81a05ea38237..07efa2b40003 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -1568,6 +1568,8 @@ static netdev_tx_t 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],
@@ -2788,7 +2790,6 @@ 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)) {
@@ -2818,14 +2819,6 @@ 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);
--
2.16.4
next reply other threads:[~2019-08-14 19:57 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-14 19:57 Thomas Falcon [this message]
2019-08-18 20:58 ` [PATCH net] ibmvnic: Unmap DMA address of TX descriptor buffers after use David Miller
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1565812625-24364-1-git-send-email-tlfalcon@linux.ibm.com \
--to=tlfalcon@linux.ibm.com \
--cc=netdev@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).