atm/nicstar: convert to idr_alloc()

Convert to the much saner new idr interface. The existing code looks
buggy to me - ID 0 is treated as no-ID but allocation specifies 0 as
lower limit and there's no error handling after partial success. This
conversion keeps the bugs unchanged.

Signed-off-by: Tejun Heo <[e-mail]>
Acked-by: Chas Williams <[e-mail]>
Reported-by: kbuild test robot <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

drivers/atm/nicstar.c

···
 static void push_rxbufs(ns_dev * card, struct sk_buff *skb)
 {
 	struct sk_buff *handle1, *handle2;
-	u32 id1 = 0, id2 = 0;
+	int id1, id2;
 	u32 addr1, addr2;
 	u32 stat;
 	unsigned long flags;
-	int err;
 
 	/* *BARF* */
 	handle2 = NULL;
···
 				card->lbfqc += 2;
 		}
 
-		do {
-			if (!idr_pre_get(&card->idr, GFP_ATOMIC)) {
-				printk(KERN_ERR
-				       "nicstar%d: no free memory for idr\n",
-				       card->index);
-				goto out;
-			}
+		id1 = idr_alloc(&card->idr, handle1, 0, 0, GFP_ATOMIC);
+		if (id1 < 0)
+			goto out;
 
-			if (!id1)
-				err = idr_get_new_above(&card->idr, handle1, 0, &id1);
-
-			if (!id2 && err == 0)
-				err = idr_get_new_above(&card->idr, handle2, 0, &id2);
-
-		} while (err == -EAGAIN);
-
-		if (err)
+		id2 = idr_alloc(&card->idr, handle2, 0, 0, GFP_ATOMIC);
+		if (id2 < 0)
 			goto out;
 
 		spin_lock_irqsave(&card->res_lock, flags);