IB/ipath: convert to idr_alloc()

Convert to the much saner new idr interface.

[yongjun_wei@trendmicro.com.cn: use GFP_NOWAIT under spin lock]
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Cc: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/infiniband/hw/ipath/ipath_driver.c

@@ -194,11 +194,6 @@ static struct ipath_devdata *ipath_alloc_devdata(struct pci_dev *pdev)
 	struct ipath_devdata *dd;
 	int ret;
 
-	if (!idr_pre_get(&unit_table, GFP_KERNEL)) {
-		dd = ERR_PTR(-ENOMEM);
-		goto bail;
-	}
-
 	dd = vzalloc(sizeof(*dd));
 	if (!dd) {
 		dd = ERR_PTR(-ENOMEM);
@@ -206,9 +201,10 @@ static struct ipath_devdata *ipath_alloc_devdata(struct pci_dev *pdev)
 	}
 	dd->ipath_unit = -1;
 
+	idr_preload(GFP_KERNEL);
 	spin_lock_irqsave(&ipath_devs_lock, flags);
 
-	ret = idr_get_new(&unit_table, dd, &dd->ipath_unit);
+	ret = idr_alloc(&unit_table, dd, 0, 0, GFP_NOWAIT);
 	if (ret < 0) {
 		printk(KERN_ERR IPATH_DRV_NAME
 		       ": Could not allocate unit ID: error %d\n", -ret);
@@ -216,6 +212,7 @@ static struct ipath_devdata *ipath_alloc_devdata(struct pci_dev *pdev)
 		dd = ERR_PTR(ret);
 		goto bail_unlock;
 	}
+	dd->ipath_unit = ret;
 
 	dd->pcidev = pdev;
 	pci_set_drvdata(pdev, dd);
@@ -224,7 +221,7 @@ static struct ipath_devdata *ipath_alloc_devdata(struct pci_dev *pdev)
 
 bail_unlock:
 	spin_unlock_irqrestore(&ipath_devs_lock, flags);
-
+	idr_preload_end();
 bail:
 	return dd;
 }
@@ -2503,11 +2500,6 @@ static int __init infinipath_init(void)
 	 * the PCI subsystem.
 	 */
 	idr_init(&unit_table);
-	if (!idr_pre_get(&unit_table, GFP_KERNEL)) {
-		printk(KERN_ERR IPATH_DRV_NAME ": idr_pre_get() failed\n");
-		ret = -ENOMEM;
-		goto bail;
-	}
 
 	ret = pci_register_driver(&ipath_driver);
 	if (ret < 0) {