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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,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 CE6CEC433DF for ; Mon, 29 Jun 2020 19:46:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AAEAB20760 for ; Mon, 29 Jun 2020 19:46:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593459967; bh=LoVIHkXo/f1i0Yzxzmm7UVOq2WlhqMhxCMJ6m/utMNQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=v6sbm6arrS8g1pTNHm4xjKe4IvLpup3xhgm+SZ3Wr1WTYB2ie8udVnzm+B+WwWmm1 nuTqSDC+DT56xDO0QIW+ozMHsvmXGwNo2gtwWQ2JEt7PLDsg8n1lnrmFHPAlwAd5B2 11A5umNqDEwqJPQEp8ex2RWb0MBoAZVBHKPcPbkc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388071AbgF2Tpw (ORCPT ); Mon, 29 Jun 2020 15:45:52 -0400 Received: from mail.kernel.org ([198.145.29.99]:47696 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387818AbgF2Tko (ORCPT ); Mon, 29 Jun 2020 15:40:44 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A633A248BD; Mon, 29 Jun 2020 15:26:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593444414; bh=LoVIHkXo/f1i0Yzxzmm7UVOq2WlhqMhxCMJ6m/utMNQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VVkvXmZWoyWkgscTqTBXFQj+4FrMi36+I3APp0gGB087iTxNd34sMBAdUvjoQ4HW0 X+ZPgkeMMHpMymDKjnZEe/sAb6IStVq4WpZLsIxTl4QdB3nD4vSau6eCvZqRBI4lJg way+Shiy9Q2IQ4beGTJ+HIOlE36DXFY0zfuP7LjY= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Alexander Lobakin , Igor Russkikh , Michal Kalderon , "David S . Miller" , Sasha Levin Subject: [PATCH 5.4 092/178] net: qed: fix left elements count calculation Date: Mon, 29 Jun 2020 11:23:57 -0400 Message-Id: <20200629152523.2494198-93-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200629152523.2494198-1-sashal@kernel.org> References: <20200629152523.2494198-1-sashal@kernel.org> MIME-Version: 1.0 X-KernelTest-Patch: http://kernel.org/pub/linux/kernel/v5.x/stable-review/patch-5.4.50-rc1.gz X-KernelTest-Tree: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git X-KernelTest-Branch: linux-5.4.y X-KernelTest-Patches: git://git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git X-KernelTest-Version: 5.4.50-rc1 X-KernelTest-Deadline: 2020-07-01T15:25+00:00 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Alexander Lobakin [ Upstream commit 97dd1abd026ae4e6a82fa68645928404ad483409 ] qed_chain_get_element_left{,_u32} returned 0 when the difference between producer and consumer page count was equal to the total page count. Fix this by conditional expanding of producer value (vs unconditional). This allowed to eliminate normalizaton against total page count, which was the cause of this bug. Misc: replace open-coded constants with common defines. Fixes: a91eb52abb50 ("qed: Revisit chain implementation") Signed-off-by: Alexander Lobakin Signed-off-by: Igor Russkikh Signed-off-by: Michal Kalderon Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- include/linux/qed/qed_chain.h | 26 ++++++++++++++++---------- 1 file changed, 16 insertions(+), 10 deletions(-) diff --git a/include/linux/qed/qed_chain.h b/include/linux/qed/qed_chain.h index 733fad7dfbed9..6d15040c642cb 100644 --- a/include/linux/qed/qed_chain.h +++ b/include/linux/qed/qed_chain.h @@ -207,28 +207,34 @@ static inline u32 qed_chain_get_cons_idx_u32(struct qed_chain *p_chain) static inline u16 qed_chain_get_elem_left(struct qed_chain *p_chain) { + u16 elem_per_page = p_chain->elem_per_page; + u32 prod = p_chain->u.chain16.prod_idx; + u32 cons = p_chain->u.chain16.cons_idx; u16 used; - used = (u16) (((u32)0x10000 + - (u32)p_chain->u.chain16.prod_idx) - - (u32)p_chain->u.chain16.cons_idx); + if (prod < cons) + prod += (u32)U16_MAX + 1; + + used = (u16)(prod - cons); if (p_chain->mode == QED_CHAIN_MODE_NEXT_PTR) - used -= p_chain->u.chain16.prod_idx / p_chain->elem_per_page - - p_chain->u.chain16.cons_idx / p_chain->elem_per_page; + used -= prod / elem_per_page - cons / elem_per_page; return (u16)(p_chain->capacity - used); } static inline u32 qed_chain_get_elem_left_u32(struct qed_chain *p_chain) { + u16 elem_per_page = p_chain->elem_per_page; + u64 prod = p_chain->u.chain32.prod_idx; + u64 cons = p_chain->u.chain32.cons_idx; u32 used; - used = (u32) (((u64)0x100000000ULL + - (u64)p_chain->u.chain32.prod_idx) - - (u64)p_chain->u.chain32.cons_idx); + if (prod < cons) + prod += (u64)U32_MAX + 1; + + used = (u32)(prod - cons); if (p_chain->mode == QED_CHAIN_MODE_NEXT_PTR) - used -= p_chain->u.chain32.prod_idx / p_chain->elem_per_page - - p_chain->u.chain32.cons_idx / p_chain->elem_per_page; + used -= (u32)(prod / elem_per_page - cons / elem_per_page); return p_chain->capacity - used; } -- 2.25.1