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From: Ladislav Michl <ladis@linux-mips.org>
To: linux-usb@vger.kernel.org
Cc: Felipe Balbi <balbi@kernel.org>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Subject: [PATCH 2/3] usb: gadget: u_serial: Remove console specific alloc/free req functions
Date: Wed, 3 Jul 2019 18:34:57 +0200	[thread overview]
Message-ID: <20190703163457.GC28579@lenoch> (raw)
In-Reply-To: <20190703163355.GA28579@lenoch>

Driver already contains request allocation and deallocation
functions, so use them also for console_req.
While console_req is always null when calling gs_console_connect
remove check and put access under con_lock as we are racing with
gs_console_thread.

Signed-off-by: Ladislav Michl <ladis@linux-mips.org>
---
 drivers/usb/gadget/function/u_serial.c | 43 +++++++-------------------
 1 file changed, 11 insertions(+), 32 deletions(-)

diff --git a/drivers/usb/gadget/function/u_serial.c b/drivers/usb/gadget/function/u_serial.c
index f8abb9c68e62..04b4338b4ae1 100644
--- a/drivers/usb/gadget/function/u_serial.c
+++ b/drivers/usb/gadget/function/u_serial.c
@@ -892,30 +892,6 @@ static struct tty_driver *gs_tty_driver;
 static struct gscons_info gscons_info;
 static struct console gserial_cons;
 
-static struct usb_request *gs_request_new(struct usb_ep *ep)
-{
-	struct usb_request *req = usb_ep_alloc_request(ep, GFP_ATOMIC);
-	if (!req)
-		return NULL;
-
-	req->buf = kmalloc(ep->maxpacket, GFP_ATOMIC);
-	if (!req->buf) {
-		usb_ep_free_request(ep, req);
-		return NULL;
-	}
-
-	return req;
-}
-
-static void gs_request_free(struct usb_request *req, struct usb_ep *ep)
-{
-	if (!req)
-		return;
-
-	kfree(req->buf);
-	usb_ep_free_request(ep, req);
-}
-
 static void gs_complete_out(struct usb_ep *ep, struct usb_request *req)
 {
 	struct gscons_info *info = &gscons_info;
@@ -954,15 +930,15 @@ static int gs_console_connect(int port_num)
 
 	port = ports[port_num].port;
 	ep = port->port_usb->in;
+	spin_lock(&info->con_lock);
+	info->console_req = gs_alloc_req(ep, ep->maxpacket, GFP_ATOMIC);
 	if (!info->console_req) {
-		info->console_req = gs_request_new(ep);
-		if (!info->console_req)
-			return -ENOMEM;
-		info->console_req->complete = gs_complete_out;
+		spin_unlock(&info->con_lock);
+		return -ENOMEM;
 	}
+	info->console_req->complete = gs_complete_out;
 
 	info->port = port;
-	spin_lock(&info->con_lock);
 	info->req_busy = 0;
 	spin_unlock(&info->con_lock);
 	pr_vdebug("port[%d] console connect!\n", port_num);
@@ -972,10 +948,13 @@ static int gs_console_connect(int port_num)
 static void gs_console_disconnect(struct usb_ep *ep)
 {
 	struct gscons_info *info = &gscons_info;
-	struct usb_request *req = info->console_req;
 
-	gs_request_free(req, ep);
-	info->console_req = NULL;
+	spin_lock(&info->con_lock);
+	if (info->console_req) {
+		gs_free_req(ep, info->console_req);
+		info->console_req = NULL;
+	}
+	spin_unlock(&info->con_lock);
 }
 
 static int gs_console_thread(void *data)
-- 
2.20.1


  parent reply	other threads:[~2019-07-03 16:35 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-07-03 16:33 [PATCH 0/3] usb: gadget: u_serial: Fix and cleanup Ladislav Michl
2019-07-03 16:34 ` [PATCH 1/3] usb: gadget: u_serial: Fix console_req complete event race Ladislav Michl
2019-07-03 16:34 ` Ladislav Michl [this message]
2019-07-03 16:35 ` [PATCH 3/3] usb: gadget: u_serial: Use bool for req_busy Ladislav Michl
2019-07-04 16:32 ` [PATCH 0/3] usb: gadget: u_serial: Fix and cleanup Ladislav Michl
2019-07-04 22:10   ` Ladislav Michl

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