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SubjectRe: [PATCH 3/3] drivers/usb/gadget: Drop NULL test on list_entry result
Thanks!

Applied.

Julia Lawall schrieb:
> From: Julia Lawall <julia@diku.dk>
>
> list_entry, which is an alias for container_of, cannot return NULL, as
> there is no way to add a NULL value to a doubly linked list.
>
> A simplified version of the semantic match that findds this problem is as
> follows:
> (http://www.emn.fr/x-info/coccinelle/)
>
> // <smpl>
> @r@
> expression x,E;
> statement S1,S2;
> position p,p1;
> @@
>
> *x = list_entry@p(...)
> ... when != x = E
> *if@p1 (x == NULL) S1 else S2
> // </smpl>
>
> Signed-off-by: Julia Lawall <julia@diku.dk>
>
> ---
> drivers/usb/gadget/amd5536udc.c | 56 +++++++++-----------
> 1 files changed, 25 insertions(+), 31 deletions(-)
>
> diff --git a/drivers/usb/gadget/amd5536udc.c b/drivers/usb/gadget/amd5536udc.c
> index 826f3ad..85f7aa9 100644
> --- a/drivers/usb/gadget/amd5536udc.c
> +++ b/drivers/usb/gadget/amd5536udc.c
> @@ -2379,40 +2379,34 @@ static irqreturn_t udc_data_in_isr(struct udc *dev, int ep_ix)
> if (!ep->cancel_transfer && !list_empty(&ep->queue)) {
> req = list_entry(ep->queue.next,
> struct udc_request, queue);
> - if (req) {
> - /*
> - * length bytes transfered
> - * check dma done of last desc. in PPBDU mode
> - */
> - if (use_dma_ppb_du) {
> - td = udc_get_last_dma_desc(req);
> - if (td) {
> - dma_done =
> - AMD_GETBITS(td->status,
> - UDC_DMA_IN_STS_BS);
> - /* don't care DMA done */
> - req->req.actual =
> - req->req.length;
> - }
> - } else {
> - /* assume all bytes transferred */
> + /*
> + * length bytes transfered
> + * check dma done of last desc. in PPBDU mode
> + */
> + if (use_dma_ppb_du) {
> + td = udc_get_last_dma_desc(req);
> + if (td) {
> + dma_done =
> + AMD_GETBITS(td->status,
> + UDC_DMA_IN_STS_BS);
> + /* don't care DMA done */
> req->req.actual = req->req.length;
> }
> + } else {
> + /* assume all bytes transferred */
> + req->req.actual = req->req.length;
> + }
>
> - if (req->req.actual == req->req.length) {
> - /* complete req */
> - complete_req(ep, req, 0);
> - req->dma_going = 0;
> - /* further request available ? */
> - if (list_empty(&ep->queue)) {
> - /* disable interrupt */
> - tmp = readl(
> - &dev->regs->ep_irqmsk);
> - tmp |= AMD_BIT(ep->num);
> - writel(tmp,
> - &dev->regs->ep_irqmsk);
> - }
> -
> + if (req->req.actual == req->req.length) {
> + /* complete req */
> + complete_req(ep, req, 0);
> + req->dma_going = 0;
> + /* further request available ? */
> + if (list_empty(&ep->queue)) {
> + /* disable interrupt */
> + tmp = readl(&dev->regs->ep_irqmsk);
> + tmp |= AMD_BIT(ep->num);
> + writel(tmp, &dev->regs->ep_irqmsk);
> }
> }
> }
>



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