| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <5639DAD8.40204@felipetonello.com>
Date: Wed, 4 Nov 2015 10:15:52 +0000
From: Felipe Ferreri Tonello <eu@...ipetonello.com>
To: Robert Baldyga <r.baldyga@...sung.com>, balbi@...com
Cc: gregkh@...uxfoundation.org, andrzej.p@...sung.com,
m.szyprowski@...sung.com, b.zolnierkie@...sung.com,
linux-usb@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 04/23] usb: gadget: f_loopback: free requests in
loopback_disable()
Hi Robert,
On 03/11/15 12:53, Robert Baldyga wrote:
> USB requests in Loopback function are allocated in loopback_get_alt()
> function, so we prefer to free them rather in loopback_disable() than
> in loopback_complete() when request is completed with error. It provides
> better symetry in resource management and improves code readability.
Are we doing this for all functions? Because I see that several
functions does the same thing, they free IN/OUT ep requests on
complete() instead of disable().
I also prefer this, but then we need to refactor most function code.
>
> Signed-off-by: Robert Baldyga <r.baldyga@...sung.com>
> ---
> drivers/usb/gadget/function/f_loopback.c | 58 +++++++++++++-------------------
> 1 file changed, 23 insertions(+), 35 deletions(-)
>
> diff --git a/drivers/usb/gadget/function/f_loopback.c b/drivers/usb/gadget/function/f_loopback.c
> index 6b2102b..41464ae 100644
> --- a/drivers/usb/gadget/function/f_loopback.c
> +++ b/drivers/usb/gadget/function/f_loopback.c
> @@ -35,6 +35,9 @@ struct f_loopback {
> struct usb_ep *in_ep;
> struct usb_ep *out_ep;
>
> + struct usb_request *in_req;
> + struct usb_request *out_req;
> +
> unsigned qlen;
> unsigned buflen;
> };
> @@ -249,30 +252,25 @@ static void loopback_complete(struct usb_ep *ep, struct usb_request *req)
> * We received some data from the host so let's
> * queue it so host can read the from our in ep
> */
> - struct usb_request *in_req = req->context;
> -
> - in_req->zero = (req->actual < req->length);
> - in_req->length = req->actual;
> + loop->in_req->zero = (req->actual < req->length);
> + loop->in_req->length = req->actual;
> + req = loop->in_req;
> ep = loop->in_ep;
> - req = in_req;
> } else {
> /*
> * We have just looped back a bunch of data
> * to host. Now let's wait for some more data.
> */
> - req = req->context;
> + req = loop->out_req;
> ep = loop->out_ep;
> }
>
> /* queue the buffer back to host or for next bunch of data */
> status = usb_ep_queue(ep, req, GFP_ATOMIC);
> - if (status == 0) {
> - return;
> - } else {
> + if (status < 0)
> ERROR(cdev, "Unable to loop back buffer to %s: %d\n",
> ep->name, status);
> - goto free_req;
> - }
> + break;
>
> /* "should never get here" */
> default:
> @@ -280,20 +278,10 @@ static void loopback_complete(struct usb_ep *ep, struct usb_request *req)
> status, req->actual, req->length);
> /* FALLTHROUGH */
>
> - /* NOTE: since this driver doesn't maintain an explicit record
> - * of requests it submitted (just maintains qlen count), we
> - * rely on the hardware driver to clean up on disconnect or
> - * endpoint disable.
> - */
> case -ECONNABORTED: /* hardware forced ep reset */
> case -ECONNRESET: /* request dequeued */
> case -ESHUTDOWN: /* disconnect from host */
> -free_req:
> - usb_ep_free_request(ep == loop->in_ep ?
> - loop->out_ep : loop->in_ep,
> - req->context);
> - free_ep_req(ep, req);
> - return;
> + break;
> }
> }
>
> @@ -316,7 +304,6 @@ static inline struct usb_request *lb_alloc_ep_req(struct usb_ep *ep, int len)
> static int alloc_requests(struct usb_composite_dev *cdev,
> struct f_loopback *loop)
> {
> - struct usb_request *in_req, *out_req;
> int i;
> int result = 0;
>
> @@ -329,23 +316,21 @@ static int alloc_requests(struct usb_composite_dev *cdev,
> for (i = 0; i < loop->qlen && result == 0; i++) {
> result = -ENOMEM;
>
> - in_req = usb_ep_alloc_request(loop->in_ep, GFP_KERNEL);
> - if (!in_req)
> + loop->in_req = usb_ep_alloc_request(loop->in_ep, GFP_KERNEL);
> + if (!loop->in_req)
> goto fail;
>
> - out_req = lb_alloc_ep_req(loop->out_ep, 0);
> - if (!out_req)
> + loop->out_req = lb_alloc_ep_req(loop->out_ep, 0);
> + if (!loop->out_req)
> goto fail_in;
>
> - in_req->complete = loopback_complete;
> - out_req->complete = loopback_complete;
> + loop->in_req->complete = loopback_complete;
> + loop->out_req->complete = loopback_complete;
>
> - in_req->buf = out_req->buf;
> + loop->in_req->buf = loop->out_req->buf;
> /* length will be set in complete routine */
> - in_req->context = out_req;
> - out_req->context = in_req;
>
> - result = usb_ep_queue(loop->out_ep, out_req, GFP_ATOMIC);
> + result = usb_ep_queue(loop->out_ep, loop->out_req, GFP_ATOMIC);
> if (result) {
> ERROR(cdev, "%s queue req --> %d\n",
> loop->out_ep->name, result);
> @@ -356,9 +341,9 @@ static int alloc_requests(struct usb_composite_dev *cdev,
> return 0;
>
> fail_out:
> - free_ep_req(loop->out_ep, out_req);
> + free_ep_req(loop->out_ep, loop->out_req);
> fail_in:
> - usb_ep_free_request(loop->in_ep, in_req);
> + usb_ep_free_request(loop->in_ep, loop->in_req);
> fail:
> return result;
> }
> @@ -426,6 +411,9 @@ static void loopback_disable(struct usb_function *f)
> struct f_loopback *loop = func_to_loop(f);
>
> disable_loopback(loop);
> +
> + free_ep_req(loop->out_ep, loop->out_req);
> + usb_ep_free_request(loop->in_ep, loop->in_req);
> }
>
> static struct usb_function *loopback_alloc(struct usb_function_instance *fi)
>
--
Felipe
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists