Convert kzalloc_obj(s) to kzalloc_flex to save an allocation.

Add __counted_by to get extra runtime analysis. Move counting variable
assignment immediately after allocation as required by __counted_by.

Signed-off-by: Rosen Penev <rosenp@gmail.com>
---
 drivers/usb/host/fhci-hcd.c | 15 +++------------
 drivers/usb/host/fhci.h     |  3 ++-
 2 files changed, 5 insertions(+), 13 deletions(-)

diff --git a/drivers/usb/host/fhci-hcd.c b/drivers/usb/host/fhci-hcd.c
index 271bcbe9b326..71e785f445a3 100644
--- a/drivers/usb/host/fhci-hcd.c
+++ b/drivers/usb/host/fhci-hcd.c
@@ -426,16 +426,11 @@ static int fhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
 	}
 
 	/* allocate the private part of the URB */
-	urb_priv = kzalloc_obj(*urb_priv, mem_flags);
+	urb_priv = kzalloc_flex(*urb_priv, tds, size, mem_flags);
 	if (!urb_priv)
 		return -ENOMEM;
 
-	/* allocate the private part of the URB */
-	urb_priv->tds = kzalloc_objs(*urb_priv->tds, size, mem_flags);
-	if (!urb_priv->tds) {
-		kfree(urb_priv);
-		return -ENOMEM;
-	}
+	urb_priv->num_of_tds = size;
 
 	spin_lock_irqsave(&fhci->lock, flags);
 
@@ -444,8 +439,6 @@ static int fhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
 		goto err;
 
 	/* fill the private part of the URB */
-	urb_priv->num_of_tds = size;
-
 	urb->status = -EINPROGRESS;
 	urb->actual_length = 0;
 	urb->error_count = 0;
@@ -453,10 +446,8 @@ static int fhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
 
 	fhci_queue_urb(fhci, urb);
 err:
-	if (ret) {
-		kfree(urb_priv->tds);
+	if (ret)
 		kfree(urb_priv);
-	}
 	spin_unlock_irqrestore(&fhci->lock, flags);
 	return ret;
 }
diff --git a/drivers/usb/host/fhci.h b/drivers/usb/host/fhci.h
index 1f57b0989485..e221b28e8608 100644
--- a/drivers/usb/host/fhci.h
+++ b/drivers/usb/host/fhci.h
@@ -387,9 +387,10 @@ struct urb_priv {
 	int tds_cnt;
 	int state;
 
-	struct td **tds;
 	struct ed *ed;
 	struct timer_list time_out;
+
+	struct td *tds[] __counted_by(num_of_tds);
 };
 
 struct endpoint {
-- 
2.53.0