From f5072556743a43716dd25e0a0bec5db4d337498f Mon Sep 17 00:00:00 2001
From: Oliver Neukum <oliver@neukum.org>
Date: Wed, 9 Sep 2009 10:23:35 +0200
Subject: [PATCH] --- yaml --- r: 165055 b: refs/heads/master c:
 798199867385417ba6494472e39c016e3340758c h: refs/heads/master i:   165053:
 c8e0dc0e740ad05b19251d3daac9ed5035907156   165051:
 e8a9268740c2189ac7ed87b0f362a71efe1644a2   165047:
 e0761719793f768055ee7155903a285fc8957c26   165039:
 2f3476f3a938bea9f636cb8010c1f1f67f752c51   165023:
 61e8a60d7b849cfbe7fe912289be92fda4ec5a8d   164991:
 63c47752f29571cd3edb27aa2755ac083ef0ebfa v: v3

---
 [refs]                           |  2 +-
 trunk/drivers/usb/usb-skeleton.c | 13 ++++++++++---
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/[refs] b/[refs]
index e11f846729bb..a14d5f315ee2 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: e7389cc9a7ff7c6e760e741c81a751c834f7d145
+refs/heads/master: 798199867385417ba6494472e39c016e3340758c
diff --git a/trunk/drivers/usb/usb-skeleton.c b/trunk/drivers/usb/usb-skeleton.c
index 5ffa3e246856..768fda9064e9 100644
--- a/trunk/drivers/usb/usb-skeleton.c
+++ b/trunk/drivers/usb/usb-skeleton.c
@@ -399,9 +399,16 @@ static ssize_t skel_write(struct file *file, const char *user_buffer, size_t cou
 		goto exit;
 
 	/* limit the number of URBs in flight to stop a user from using up all RAM */
-	if (down_interruptible(&dev->limit_sem)) {
-		retval = -ERESTARTSYS;
-		goto exit;
+	if (!file->f_flags & O_NONBLOCK) {
+		if (down_interruptible(&dev->limit_sem)) {
+			retval = -ERESTARTSYS;
+			goto exit;
+		}
+	} else {
+		if (down_trylock(&dev->limit_sem)) {
+			retval = -EAGAIN;
+			goto exit;
+		}
 	}
 
 	spin_lock_irq(&dev->err_lock);