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=unavailable 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 75AF0C433DF for ; Mon, 29 Jun 2020 20:26:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5411620656 for ; Mon, 29 Jun 2020 20:26:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593462367; bh=LoVIHkXo/f1i0Yzxzmm7UVOq2WlhqMhxCMJ6m/utMNQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=O/U3bpZk5L8bZxreAMXVhJtvX+/45V5IpYp3goS9scB1VJDOMjWlbbK5mdThLY8Jd s39E6HfPc7cKpf5C7F2Q8P1UAzUasibEUOEans+/RAbok67qT0pFx8fIMXo0Rni5MK k86C/OkJBE1ISGey5bCuaWTgrqfZo7b8JnSv3Axc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732120AbgF2U0F (ORCPT ); Mon, 29 Jun 2020 16:26:05 -0400 Received: from mail.kernel.org ([198.145.29.99]:37058 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732528AbgF2TZ0 (ORCPT ); Mon, 29 Jun 2020 15:25:26 -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 72C7425312; Mon, 29 Jun 2020 15:39:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593445141; bh=LoVIHkXo/f1i0Yzxzmm7UVOq2WlhqMhxCMJ6m/utMNQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VIMbEV7xbpV4BTWBOEN7wDhjXwnmPMstnqSPvbpzNXOy5Ru2CNJEUOWsMmt7mHfHq wdiJ9W2sxabTUqCrmFr/JouEOGugJP+CHy62ybl1HOlh8SSy8TFED4z0w4xH6elLz6 QB5bZHhRaYp6qZqQ4iN5lYmvjOtL77DUxp/knp/8= 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 4.14 46/78] net: qed: fix left elements count calculation Date: Mon, 29 Jun 2020 11:37:34 -0400 Message-Id: <20200629153806.2494953-47-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200629153806.2494953-1-sashal@kernel.org> References: <20200629153806.2494953-1-sashal@kernel.org> MIME-Version: 1.0 X-KernelTest-Patch: http://kernel.org/pub/linux/kernel/v4.x/stable-review/patch-4.14.186-rc1.gz X-KernelTest-Tree: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git X-KernelTest-Branch: linux-4.14.y X-KernelTest-Patches: git://git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git X-KernelTest-Version: 4.14.186-rc1 X-KernelTest-Deadline: 2020-07-01T15:38+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