From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932809AbbBZOLD (ORCPT ); Thu, 26 Feb 2015 09:11:03 -0500 Received: from mail-pd0-f172.google.com ([209.85.192.172]:34392 "EHLO mail-pd0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932535AbbBZOK5 (ORCPT ); Thu, 26 Feb 2015 09:10:57 -0500 From: Sergey Senozhatsky To: Andrew Morton , Minchan Kim Cc: Jerome Marchand , Nitin Gupta , Sergey Senozhatsky , linux-kernel@vger.kernel.org, Sergey Senozhatsky Subject: [PATCH 5/8] zram: return zram device_id value from zram_add() Date: Thu, 26 Feb 2015 23:10:40 +0900 Message-Id: <1424959843-20409-6-git-send-email-sergey.senozhatsky@gmail.com> X-Mailer: git-send-email 2.3.1.167.g7f4ba4b In-Reply-To: <1424959843-20409-1-git-send-email-sergey.senozhatsky@gmail.com> References: <1424959843-20409-1-git-send-email-sergey.senozhatsky@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ZRAM_CTL_ADD ioctl requires valid device_id to be provided, that can be a bit inconvenient. Change zram_add() to return negative value upon new device creation failure, and device_id (>= 0) value otherwise. This prepares ZRAM_CTL_ADD to perform automatic device_id assignment. New device_id will be returned back to user-space (so user can reference that device as zram%d device_id). Signed-off-by: Sergey Senozhatsky --- drivers/block/zram/zram_drv.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index 4f87d1e..0154c2d4 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -1078,6 +1078,8 @@ static struct zram *zram_lookup(int dev_id) return ERR_PTR(-ENODEV); } +/* allocate and initialize new zram device. the function returns >= 0 + * device_id value upon success, and negative value otherwise. */ static int zram_add(int device_id) { struct zram *zram; @@ -1161,7 +1163,7 @@ static int zram_add(int device_id) strlcpy(zram->compressor, default_compressor, sizeof(zram->compressor)); zram->meta = NULL; zram->max_comp_streams = 1; - return 0; + return device_id; out_free_disk: del_gendisk(zram->disk); @@ -1303,7 +1305,7 @@ static int __init zram_init(void) mutex_lock(&zram_index_mutex); ret = zram_add(dev_id); mutex_unlock(&zram_index_mutex); - if (ret != 0) + if (ret < 0) goto out_error; } -- 2.3.1.167.g7f4ba4b