block: convert to idr_alloc()

Convert to the much saner new idr interface.  Both bsg and genhd
protect idr w/ mutex making preloading unnecessary.

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>

1 files changed, 9 insertions, 17 deletions

diff --git a/block/bsg.c b/block/bsg.c
index ff64ae3..3ca92eb 100644
--- a/block/bsg.c
+++ b/block/bsg.c
@@ -997,7 +997,7 @@ int bsg_register_queue(struct request_queue *q, struct device *parent,
 {
 	struct bsg_class_device *bcd;
 	dev_t dev;
-	int ret, minor;
+	int ret;
 	struct device *class_dev = NULL;
 	const char *devname;
 
@@ -1017,23 +1017,16 @@ int bsg_register_queue(struct request_queue *q, struct device *parent,
 
 	mutex_lock(&bsg_mutex);
 
-	ret = idr_pre_get(&bsg_minor_idr, GFP_KERNEL);
-	if (!ret) {
-		ret = -ENOMEM;
-		goto unlock;
-	}
-
-	ret = idr_get_new(&bsg_minor_idr, bcd, &minor);
-	if (ret < 0)
+	ret = idr_alloc(&bsg_minor_idr, bcd, 0, BSG_MAX_DEVS, GFP_KERNEL);
+	if (ret < 0) {
+		if (ret == -ENOSPC) {
+			printk(KERN_ERR "bsg: too many bsg devices\n");
+			ret = -EINVAL;
+		}
 		goto unlock;
-
-	if (minor >= BSG_MAX_DEVS) {
-		printk(KERN_ERR "bsg: too many bsg devices\n");
-		ret = -EINVAL;
-		goto remove_idr;
 	}
 
-	bcd->minor = minor;
+	bcd->minor = ret;
 	bcd->queue = q;
 	bcd->parent = get_device(parent);
 	bcd->release = release;
@@ -1059,8 +1052,7 @@ unregister_class_dev:
 	device_unregister(class_dev);
 put_dev:
 	put_device(parent);
-remove_idr:
-	idr_remove(&bsg_minor_idr, minor);
+	idr_remove(&bsg_minor_idr, bcd->minor);
 unlock:
 	mutex_unlock(&bsg_mutex);
 	return ret;