From: Tejun Heo <tj@kernel.org>
Date: Thu, 28 Feb 2013 01:03:58 +0000 (-0800)
Subject: block/loop: convert to idr_alloc()
X-Git-Tag: accepted/tizen/common/20141203.182822~2762^2~98
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=c718aa652d3def382a79c25442c2a830263e52ed;p=platform%2Fkernel%2Flinux-arm64.git

block/loop: convert to idr_alloc()

Convert to the much saner new idr interface.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index c674e54..f47dccb 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -1624,30 +1624,17 @@ static int loop_add(struct loop_device **l, int i)
 	if (!lo)
 		goto out;
 
-	if (!idr_pre_get(&loop_index_idr, GFP_KERNEL))
-		goto out_free_dev;
-
+	/* allocate id, if @id >= 0, we're requesting that specific id */
 	if (i >= 0) {
-		int m;
-
-		/* create specific i in the index */
-		err = idr_get_new_above(&loop_index_idr, lo, i, &m);
-		if (err >= 0 && i != m) {
-			idr_remove(&loop_index_idr, m);
+		err = idr_alloc(&loop_index_idr, lo, i, i + 1, GFP_KERNEL);
+		if (err == -ENOSPC)
 			err = -EEXIST;
-		}
-	} else if (i == -1) {
-		int m;
-
-		/* get next free nr */
-		err = idr_get_new(&loop_index_idr, lo, &m);
-		if (err >= 0)
-			i = m;
 	} else {
-		err = -EINVAL;
+		err = idr_alloc(&loop_index_idr, lo, 0, 0, GFP_KERNEL);
 	}
 	if (err < 0)
 		goto out_free_dev;
+	i = err;
 
 	lo->lo_queue = blk_alloc_queue(GFP_KERNEL);
 	if (!lo->lo_queue)