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=-9.3 required=3.0 tests=DKIM_ADSP_CUSTOM_MED, DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 E9BEEC32750 for ; Tue, 13 Aug 2019 06:16:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B5DCD20663 for ; Tue, 13 Aug 2019 06:16:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Ml6oknAs" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727259AbfHMGQl (ORCPT ); Tue, 13 Aug 2019 02:16:41 -0400 Received: from mail-pf1-f196.google.com ([209.85.210.196]:46261 "EHLO mail-pf1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727371AbfHMGQl (ORCPT ); Tue, 13 Aug 2019 02:16:41 -0400 Received: by mail-pf1-f196.google.com with SMTP id q139so2687790pfc.13; Mon, 12 Aug 2019 23:16:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=B2CMaPmFhgUSczabgn5seFFKFRX7ZBQEwXOP5kflvzo=; b=Ml6oknAsiRFd4vCBJ/hwVG6uWWhKFVd8S59qLwviy4Z0UqegjzZw3JmkrDl6JneFki JkJCJfKLVLDni3+XaQEzQBgT38/YR64J4PHtE2dc8OczIoJqZg7gfiGOdpAM9Wnx7HxK l5ZQh1merYV2b+HRftirYLMgUbJuRV70WhYNsVlM7JGi0a0+0K+LYsyb6lU7uFgvmdXH xoi1NI4okaQ25Wy4yIKFKznUhyXMgUJ/jTnJfhuPNIoxG9kijOaZ5wcMRacb2ogO1vdk tWIlCWUhLRBX0ZHfr8NfNiKpxRO1JAIJ6Q7giL0uA1x9nslMd6cmZPWtuOLkLST2LR8e ubmg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=B2CMaPmFhgUSczabgn5seFFKFRX7ZBQEwXOP5kflvzo=; b=LRzY98EBmVxbK1LMlOOtrHLZDxa+tou2pTEJp/tTfhxYw1mROldveQN8pd0yzpPjrj dZPaEc9s/ZO58mxFmXrpsu8O33OyKHJum+dRKg0kxeXZSH0sdEvVwNh7Ph+cPUVxz8Lv /+SjMcP2DceGriE8yqfQrBKKLrqDsiyorRZPT5ilR3YAkOALDh/nwmpWvvj4o3LYzuQT BrFL4Yt00YpaO2+BeJxmS+aBo3n+kDE6KS2Cx0BM1bYsVHIygDfgLRhS0ujymS+G1SRC 2aLCX/YqPj1YRbIFBZBF4TBUb7SgLSMH3rVjEdB9eokbCkBr3W+rJfL7fk3VaduBaYnC 81Pw== X-Gm-Message-State: APjAAAUssHd56YArNpgSmwuhmmzCgf3gUgKNTkYMDaFZldAIdQxekAn3 Ovh8PQrutved6v7Dkfx7OsGSahSsncWp0g== X-Google-Smtp-Source: APXvYqzkzJPidjPjU0th78+XWXE74z4yAjTlizY/SeAc2LinQjY4m8SinjVPc2zpTzshJdaQFboG6w== X-Received: by 2002:a62:2c93:: with SMTP id s141mr22093710pfs.114.1565677000124; Mon, 12 Aug 2019 23:16:40 -0700 (PDT) Received: from suzukaze.ipads-lab.se.sjtu.edu.cn ([89.31.126.54]) by smtp.gmail.com with ESMTPSA id w9sm5803654pfn.19.2019.08.12.23.16.37 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Mon, 12 Aug 2019 23:16:39 -0700 (PDT) From: Chuhong Yuan Cc: Philipp Reisner , Lars Ellenberg , Jens Axboe , drbd-dev@lists.linbit.com, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, Chuhong Yuan Subject: [PATCH v2 1/3] drbd: Use refcount_t for refcount Date: Tue, 13 Aug 2019 14:16:34 +0800 Message-Id: <20190813061634.5372-1-hslester96@gmail.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit To: unlisted-recipients:; (no To-header on input) Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Reference counters are preferred to use refcount_t instead of atomic_t. This is because the implementation of refcount_t can prevent overflows and detect possible use-after-free. So convert atomic_t ref counters to refcount_t. Signed-off-by: Chuhong Yuan --- drivers/block/drbd/drbd_int.h | 3 ++- drivers/block/drbd/drbd_main.c | 4 ++-- drivers/block/drbd/drbd_req.c | 16 ++++++++-------- 3 files changed, 12 insertions(+), 11 deletions(-) diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h index ddbf56014c51..d5167a7a87db 100644 --- a/drivers/block/drbd/drbd_int.h +++ b/drivers/block/drbd/drbd_int.h @@ -30,6 +30,7 @@ #include #include #include +#include #include #include #include @@ -354,7 +355,7 @@ struct drbd_request { /* once it hits 0, we may complete the master_bio */ - atomic_t completion_ref; + refcount_t completion_ref; /* once it hits 0, we may destroy this drbd_request object */ struct kref kref; diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c index 9bd4ddd12b25..37746708ee84 100644 --- a/drivers/block/drbd/drbd_main.c +++ b/drivers/block/drbd/drbd_main.c @@ -2295,14 +2295,14 @@ static void do_retry(struct work_struct *ws) bool expected; expected = - expect(atomic_read(&req->completion_ref) == 0) && + expect(refcount_read(&req->completion_ref) == 0) && expect(req->rq_state & RQ_POSTPONED) && expect((req->rq_state & RQ_LOCAL_PENDING) == 0 || (req->rq_state & RQ_LOCAL_ABORTED) != 0); if (!expected) drbd_err(device, "req=%p completion_ref=%d rq_state=%x\n", - req, atomic_read(&req->completion_ref), + req, refcount_read(&req->completion_ref), req->rq_state); /* We still need to put one kref associated with the diff --git a/drivers/block/drbd/drbd_req.c b/drivers/block/drbd/drbd_req.c index f86cea4c0f8d..cb5d573e7ea2 100644 --- a/drivers/block/drbd/drbd_req.c +++ b/drivers/block/drbd/drbd_req.c @@ -69,7 +69,7 @@ static struct drbd_request *drbd_req_new(struct drbd_device *device, struct bio INIT_LIST_HEAD(&req->req_pending_local); /* one reference to be put by __drbd_make_request */ - atomic_set(&req->completion_ref, 1); + refcount_set(&req->completion_ref, 1); /* one kref as long as completion_ref > 0 */ kref_init(&req->kref); return req; @@ -95,11 +95,11 @@ void drbd_req_destroy(struct kref *kref) const unsigned s = req->rq_state; if ((req->master_bio && !(s & RQ_POSTPONED)) || - atomic_read(&req->completion_ref) || + refcount_read(&req->completion_ref) || (s & RQ_LOCAL_PENDING) || ((s & RQ_NET_MASK) && !(s & RQ_NET_DONE))) { drbd_err(device, "drbd_req_destroy: Logic BUG rq_state = 0x%x, completion_ref = %d\n", - s, atomic_read(&req->completion_ref)); + s, refcount_read(&req->completion_ref)); return; } @@ -315,7 +315,7 @@ static void drbd_req_put_completion_ref(struct drbd_request *req, struct bio_and if (!put) return; - if (!atomic_sub_and_test(put, &req->completion_ref)) + if (!refcount_sub_and_test(put, &req->completion_ref)) return; drbd_req_complete(req, m); @@ -440,15 +440,15 @@ static void mod_rq_state(struct drbd_request *req, struct bio_and_error *m, kref_get(&req->kref); if (!(s & RQ_LOCAL_PENDING) && (set & RQ_LOCAL_PENDING)) - atomic_inc(&req->completion_ref); + refcount_inc(&req->completion_ref); if (!(s & RQ_NET_PENDING) && (set & RQ_NET_PENDING)) { inc_ap_pending(device); - atomic_inc(&req->completion_ref); + refcount_inc(&req->completion_ref); } if (!(s & RQ_NET_QUEUED) && (set & RQ_NET_QUEUED)) { - atomic_inc(&req->completion_ref); + refcount_inc(&req->completion_ref); set_if_null_req_next(peer_device, req); } @@ -466,7 +466,7 @@ static void mod_rq_state(struct drbd_request *req, struct bio_and_error *m, } if (!(s & RQ_COMPLETION_SUSP) && (set & RQ_COMPLETION_SUSP)) - atomic_inc(&req->completion_ref); + refcount_inc(&req->completion_ref); /* progress: put references */ -- 2.20.1