From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753201AbbEDMki (ORCPT ); Mon, 4 May 2015 08:40:38 -0400 Received: from mail-pd0-f182.google.com ([209.85.192.182]:33578 "EHLO mail-pd0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752760AbbEDMkK (ORCPT ); Mon, 4 May 2015 08:40:10 -0400 From: Sergey Senozhatsky To: Andrew Morton , Minchan Kim Cc: Nitin Gupta , linux-kernel@vger.kernel.org, Sergey Senozhatsky , Sergey Senozhatsky Subject: [PATCHv4 08/10] zram: return zram device_id from zram_add() Date: Mon, 4 May 2015 21:39:00 +0900 Message-Id: <1430743142-15854-9-git-send-email-sergey.senozhatsky@gmail.com> X-Mailer: git-send-email 2.4.0 In-Reply-To: <1430743142-15854-1-git-send-email-sergey.senozhatsky@gmail.com> References: <1430743142-15854-1-git-send-email-sergey.senozhatsky@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch prepares zram to enable on-demand device creation. zram_add() performs automatic device_id assignment and returns new device id (>= 0) or error code (< 0). Acked-by: Minchan Kim Signed-off-by: Sergey Senozhatsky --- drivers/block/zram/zram_drv.c | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-) diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index 37a753c..3df4394 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -1151,20 +1151,24 @@ static struct attribute_group zram_disk_attr_group = { .attrs = zram_disk_attrs, }; -static int zram_add(int device_id) +/* + * Allocate and initialize new zram device. the function returns + * '>= 0' device_id upon success, and negative value otherwise. + */ +static int zram_add(void) { struct zram *zram; struct request_queue *queue; - int ret; + int ret, device_id; zram = kzalloc(sizeof(struct zram), GFP_KERNEL); if (!zram) return -ENOMEM; - ret = idr_alloc(&zram_index_idr, zram, device_id, - device_id + 1, GFP_KERNEL); + ret = idr_alloc(&zram_index_idr, zram, 0, 0, GFP_KERNEL); if (ret < 0) goto out_free_dev; + device_id = ret; init_rwsem(&zram->init_lock); @@ -1238,7 +1242,7 @@ static int zram_add(int device_id) zram->max_comp_streams = 1; pr_info("Added device: %s\n", zram->disk->disk_name); - return 0; + return device_id; out_free_disk: del_gendisk(zram->disk); @@ -1285,7 +1289,7 @@ static void destroy_devices(void) static int __init zram_init(void) { - int ret, dev_id; + int ret; zram_major = register_blkdev(0, "zram"); if (zram_major <= 0) { @@ -1293,10 +1297,11 @@ static int __init zram_init(void) return -EBUSY; } - for (dev_id = 0; dev_id < num_devices; dev_id++) { - ret = zram_add(dev_id); - if (ret != 0) + while (num_devices != 0) { + ret = zram_add(); + if (ret < 0) goto out_error; + num_devices--; } return 0; -- 2.4.0