From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9C001C43381 for ; Wed, 27 Mar 2019 12:42:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 76F922087C for ; Wed, 27 Mar 2019 12:42:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728621AbfC0MmQ (ORCPT ); Wed, 27 Mar 2019 08:42:16 -0400 Received: from mga12.intel.com ([192.55.52.136]:33721 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728565AbfC0MmP (ORCPT ); Wed, 27 Mar 2019 08:42:15 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga106.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 27 Mar 2019 05:42:15 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.60,276,1549958400"; d="scan'208";a="137680474" Received: from gklab-107-059.igk.intel.com ([10.102.107.59]) by orsmga003.jf.intel.com with ESMTP; 27 Mar 2019 05:42:14 -0700 From: Igor Konopko To: mb@lightnvm.io, javier@javigon.com, hans.holmberg@cnexlabs.com Cc: linux-block@vger.kernel.org, igor.j.konopko@intel.com Subject: [PATCH v3 10/10] lightnvm: track inflight target creations Date: Wed, 27 Mar 2019 13:39:01 +0100 Message-Id: <20190327123901.12323-11-igor.j.konopko@intel.com> X-Mailer: git-send-email 2.9.5 In-Reply-To: <20190327123901.12323-1-igor.j.konopko@intel.com> References: <20190327123901.12323-1-igor.j.konopko@intel.com> Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org This patch adds a counter, which is responsible for tracking inflight target creations. When creation process is still in progress, target is not yet on targets list. This causes a chance for removing whole lightnvm subsystem by calling nvm_unregister() in the meantime and finally by causing kernel panic inside target init function. With this patch we are able to track such a scenarios and wait with completing nvm_unregister() and freeing memory until target creation will be completed. Signed-off-by: Igor Konopko --- drivers/lightnvm/core.c | 19 ++++++++++++++++++- include/linux/lightnvm.h | 2 ++ 2 files changed, 20 insertions(+), 1 deletion(-) diff --git a/drivers/lightnvm/core.c b/drivers/lightnvm/core.c index e2abe88..62ed662 100644 --- a/drivers/lightnvm/core.c +++ b/drivers/lightnvm/core.c @@ -1083,6 +1083,7 @@ static int nvm_core_init(struct nvm_dev *dev) INIT_LIST_HEAD(&dev->targets); mutex_init(&dev->mlock); spin_lock_init(&dev->lock); + dev->create_inflight = 0; ret = nvm_register_map(dev); if (ret) @@ -1180,6 +1181,11 @@ void nvm_unregister(struct nvm_dev *dev) struct nvm_target *t, *tmp; mutex_lock(&dev->mlock); + while (dev->create_inflight > 0) { + mutex_unlock(&dev->mlock); + io_schedule(); + mutex_lock(&dev->mlock); + } list_for_each_entry_safe(t, tmp, &dev->targets, list) { if (t->dev->parent != dev) continue; @@ -1198,6 +1204,7 @@ EXPORT_SYMBOL(nvm_unregister); static int __nvm_configure_create(struct nvm_ioctl_create *create) { struct nvm_dev *dev; + int ret; down_write(&nvm_lock); dev = nvm_find_nvm_dev(create->dev); @@ -1208,7 +1215,17 @@ static int __nvm_configure_create(struct nvm_ioctl_create *create) return -EINVAL; } - return nvm_create_tgt(dev, create); + mutex_lock(&dev->mlock); + dev->create_inflight++; + mutex_unlock(&dev->mlock); + + ret = nvm_create_tgt(dev, create); + + mutex_lock(&dev->mlock); + dev->create_inflight--; + mutex_unlock(&dev->mlock); + + return ret; } static long nvm_ioctl_info(struct file *file, void __user *arg) diff --git a/include/linux/lightnvm.h b/include/linux/lightnvm.h index d3b0270..e462d1d 100644 --- a/include/linux/lightnvm.h +++ b/include/linux/lightnvm.h @@ -428,6 +428,8 @@ struct nvm_dev { char name[DISK_NAME_LEN]; void *private_data; + int create_inflight; + void *rmap; struct mutex mlock; -- 2.9.5