[PATCH 5.7 160/265] usb: renesas_usbhs: getting residue from callback_result

Sasha Levin
2020-06-29T21:54:34Z

From: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>

[ Upstream commit ea0efd687b01355cd799c8643d0c636ba4859ffc ]

This driver assumed that dmaengine_tx_status() could return
the residue even if the transfer was completed. However,
this was not correct usage [1] and this caused to break getting
the residue after the commit 24461d9792c2 ("dmaengine:
virt-dma: Fix access after free in vchan_complete()") actually.
So, this is possible to get wrong received size if the usb
controller gets a short packet. For example, g_zero driver
causes "bad OUT byte" errors.

The usb-dmac driver will support the callback_result, so this
driver can use it to get residue correctly. Note that even if
the usb-dmac driver has not supported the callback_result yet,
this patch doesn't cause any side-effects.

[1]
https://lore.kernel.org/dmaengine/20200616165550.GP2324254@vkoul-mobl/

Reported-by: Hien Dang <hien.dang.eb@renesas.com>
Fixes: 24461d9792c2 ("dmaengine: virt-dma: Fix access after free in vchan_complete()")
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/1592482277-19563-1-git-send-email-yoshihiro.shimoda.uh@renesas.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/usb/renesas_usbhs/fifo.c | 23 +++++++++++++----------
drivers/usb/renesas_usbhs/fifo.h | 2 +-
2 files changed, 14 insertions(+), 11 deletions(-)

diff --git a/drivers/usb/renesas_usbhs/fifo.c b/drivers/usb/renesas_usbhs/fifo.c
index 01c6a48c41bc9..ac9a81ae82164 100644
--- a/drivers/usb/renesas_usbhs/fifo.c
+++ b/drivers/usb/renesas_usbhs/fifo.c
@@ -803,7 +803,8 @@ static int __usbhsf_dma_map_ctrl(struct usbhs_pkt *pkt, int map)
return info->dma_map_ctrl(chan->device->dev, pkt, map);
}

-static void usbhsf_dma_complete(void *arg);
+static void usbhsf_dma_complete(void *arg,
+ const struct dmaengine_result *result);
static void usbhsf_dma_xfer_preparing(struct usbhs_pkt *pkt)
{
struct usbhs_pipe *pipe = pkt->pipe;
@@ -813,6 +814,7 @@ static void usbhsf_dma_xfer_preparing(struct usbhs_pkt *pkt)
struct dma_chan *chan;
struct device *dev = usbhs_priv_to_dev(priv);
enum dma_transfer_direction dir;
+ dma_cookie_t cookie;

fifo = usbhs_pipe_to_fifo(pipe);
if (!fifo)
@@ -827,11 +829,11 @@ static void usbhsf_dma_xfer_preparing(struct usbhs_pkt *pkt)
if (!desc)
return;

- desc->callback = usbhsf_dma_complete;
- desc->callback_param = pipe;
+ desc->callback_result = usbhsf_dma_complete;
+ desc->callback_param = pkt;

- pkt->cookie = dmaengine_submit(desc);
- if (pkt->cookie < 0) {
+ cookie = dmaengine_submit(desc);
+ if (cookie < 0) {
dev_err(dev, "Failed to submit dma descriptor\n");
return;
}
@@ -1152,12 +1154,10 @@ static size_t usbhs_dma_calc_received_size(struct usbhs_pkt *pkt,
struct dma_chan *chan, int dtln)
{
struct usbhs_pipe *pipe = pkt->pipe;
- struct dma_tx_state state;
size_t received_size;
int maxp = usbhs_pipe_get_maxpacket(pipe);

- dmaengine_tx_status(chan, pkt->cookie, &state);
- received_size = pkt->length - state.residue;
+ received_size = pkt->length - pkt->dma_result->residue;

if (dtln) {
received_size -= USBHS_USB_DMAC_XFER_SIZE;
@@ -1363,13 +1363,16 @@ static int usbhsf_irq_ready(struct usbhs_priv *priv,
return 0;
}

-static void usbhsf_dma_complete(void *arg)
+static void usbhsf_dma_complete(void *arg,
+ const struct dmaengine_result *result)
{
- struct usbhs_pipe *pipe = arg;
+ struct usbhs_pkt *pkt = arg;
+ struct usbhs_pipe *pipe = pkt->pipe;
struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);
struct device *dev = usbhs_priv_to_dev(priv);
int ret;

+ pkt->dma_result = result;
ret = usbhsf_pkt_handler(pipe, USBHSF_PKT_DMA_DONE);
if (ret < 0)
dev_err(dev, "dma_complete run_error %d : %d\n",
diff --git a/drivers/usb/renesas_usbhs/fifo.h b/drivers/usb/renesas_usbhs/fifo.h
index c3d3cc35cee0f..4a7dc23ce3d35 100644
--- a/drivers/usb/renesas_usbhs/fifo.h
+++ b/drivers/usb/renesas_usbhs/fifo.h
@@ -50,7 +50,7 @@ struct usbhs_pkt {
struct usbhs_pkt *pkt);
struct work_struct work;
dma_addr_t dma;
- dma_cookie_t cookie;
+ const struct dmaengine_result *dma_result;
void *buf;
int length;
int trans;
--
2.25.1