From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 504771ED38 for ; Tue, 25 Jul 2023 11:17:13 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C7B7FC433C8; Tue, 25 Jul 2023 11:17:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1690283833; bh=sLI5jFOQC5lhvYPsoEmpMEImX2r2RIbCFH9SYL7BVP4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=AuyD4LYwFViQo6pKE6tWMRuiWbvJoHrFglDlEz/gVkiYXXG5m06kPKaGZWXI7MD6p BCfkPWNNOBIJihBJzscWOXCLrZQ+NFOAUyBrieoJsU++bdi1IAOy6B8uGVj3zBnDC1 RqXgupaRsbM1HPSpn3XWO2Lz5HMwF/1mOfHhiMRY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Weihang Li , Jason Gunthorpe , Sasha Levin Subject: [PATCH 5.10 138/509] RDMA/hns: Use refcount_t APIs for HEM Date: Tue, 25 Jul 2023 12:41:17 +0200 Message-ID: <20230725104600.070696211@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230725104553.588743331@linuxfoundation.org> References: <20230725104553.588743331@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Weihang Li [ Upstream commit 82eb481da64586ccd287b2b2c5a086202c65e7eb ] refcount_t is better than integer for reference counting, it will WARN on overflow/underflow and avoid use-after-free risks. Link: https://lore.kernel.org/r/1621589395-2435-5-git-send-email-liweihang@huawei.com Signed-off-by: Weihang Li Signed-off-by: Jason Gunthorpe Stable-dep-of: cf5b608fb0e3 ("RDMA/hns: Fix hns_roce_table_get return value") Signed-off-by: Sasha Levin --- drivers/infiniband/hw/hns/hns_roce_hem.c | 32 +++++++++++------------- drivers/infiniband/hw/hns/hns_roce_hem.h | 4 +-- 2 files changed, 17 insertions(+), 19 deletions(-) diff --git a/drivers/infiniband/hw/hns/hns_roce_hem.c b/drivers/infiniband/hw/hns/hns_roce_hem.c index edc287a0a91a1..831e9476c6284 100644 --- a/drivers/infiniband/hw/hns/hns_roce_hem.c +++ b/drivers/infiniband/hw/hns/hns_roce_hem.c @@ -260,7 +260,6 @@ static struct hns_roce_hem *hns_roce_alloc_hem(struct hns_roce_dev *hr_dev, if (!hem) return NULL; - hem->refcount = 0; INIT_LIST_HEAD(&hem->chunk_list); order = get_order(hem_alloc_size); @@ -607,7 +606,7 @@ static int hns_roce_table_mhop_get(struct hns_roce_dev *hr_dev, mutex_lock(&table->mutex); if (table->hem[index.buf]) { - ++table->hem[index.buf]->refcount; + refcount_inc(&table->hem[index.buf]->refcount); goto out; } @@ -626,7 +625,7 @@ static int hns_roce_table_mhop_get(struct hns_roce_dev *hr_dev, } } - ++table->hem[index.buf]->refcount; + refcount_set(&table->hem[index.buf]->refcount, 1); goto out; err_alloc: @@ -652,7 +651,7 @@ int hns_roce_table_get(struct hns_roce_dev *hr_dev, mutex_lock(&table->mutex); if (table->hem[i]) { - ++table->hem[i]->refcount; + refcount_inc(&table->hem[i]->refcount); goto out; } @@ -675,7 +674,7 @@ int hns_roce_table_get(struct hns_roce_dev *hr_dev, goto out; } - ++table->hem[i]->refcount; + refcount_set(&table->hem[i]->refcount, 1); out: mutex_unlock(&table->mutex); return ret; @@ -742,11 +741,11 @@ static void hns_roce_table_mhop_put(struct hns_roce_dev *hr_dev, return; } - mutex_lock(&table->mutex); - if (check_refcount && (--table->hem[index.buf]->refcount > 0)) { - mutex_unlock(&table->mutex); + if (!check_refcount) + mutex_lock(&table->mutex); + else if (!refcount_dec_and_mutex_lock(&table->hem[index.buf]->refcount, + &table->mutex)) return; - } clear_mhop_hem(hr_dev, table, obj, &mhop, &index); free_mhop_hem(hr_dev, table, &mhop, &index); @@ -768,16 +767,15 @@ void hns_roce_table_put(struct hns_roce_dev *hr_dev, i = (obj & (table->num_obj - 1)) / (table->table_chunk_size / table->obj_size); - mutex_lock(&table->mutex); + if (!refcount_dec_and_mutex_lock(&table->hem[i]->refcount, + &table->mutex)) + return; - if (--table->hem[i]->refcount == 0) { - /* Clear HEM base address */ - if (hr_dev->hw->clear_hem(hr_dev, table, obj, 0)) - dev_warn(dev, "Clear HEM base address failed.\n"); + if (hr_dev->hw->clear_hem(hr_dev, table, obj, 0)) + dev_warn(dev, "failed to clear HEM base address.\n"); - hns_roce_free_hem(hr_dev, table->hem[i]); - table->hem[i] = NULL; - } + hns_roce_free_hem(hr_dev, table->hem[i]); + table->hem[i] = NULL; mutex_unlock(&table->mutex); } diff --git a/drivers/infiniband/hw/hns/hns_roce_hem.h b/drivers/infiniband/hw/hns/hns_roce_hem.h index 112243d112c23..03d44e2efa473 100644 --- a/drivers/infiniband/hw/hns/hns_roce_hem.h +++ b/drivers/infiniband/hw/hns/hns_roce_hem.h @@ -87,8 +87,8 @@ struct hns_roce_hem_chunk { }; struct hns_roce_hem { - struct list_head chunk_list; - int refcount; + struct list_head chunk_list; + refcount_t refcount; }; struct hns_roce_hem_iter { -- 2.39.2