From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by inbox.dpdk.org (Postfix) with ESMTP id 00927A046B for ; Thu, 25 Jul 2019 19:04:19 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 8F7A91C3A4; Thu, 25 Jul 2019 19:04:18 +0200 (CEST) Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by dpdk.org (Postfix) with ESMTP id BEE9D1C39C for ; Thu, 25 Jul 2019 19:04:16 +0200 (CEST) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 25 Jul 2019 10:04:15 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.64,307,1559545200"; d="scan'208";a="197944853" Received: from sivswdev09.ir.intel.com (HELO localhost.localdomain) ([10.237.217.48]) by fmsmga002.fm.intel.com with ESMTP; 25 Jul 2019 10:04:14 -0700 From: Fiona Trahe To: dev@dpdk.org Cc: akhil.goyal@nxp.com, fiona.trahe@intel.com, shallyv@marvell.com Date: Thu, 25 Jul 2019 18:04:09 +0100 Message-Id: <1564074249-16222-1-git-send-email-fiona.trahe@intel.com> X-Mailer: git-send-email 1.7.0.7 Subject: [dpdk-dev] [PATCH] compressdev: clarify destination buffer size for corner case X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" Clarify the corner case with incompressible data whereby the output can actually be greater than the uncompressed data. Signed-off-by: Fiona Trahe --- lib/librte_compressdev/rte_comp.h | 6 ++++++ 1 files changed, 6 insertions(+), 0 deletions(-) diff --git a/lib/librte_compressdev/rte_comp.h b/lib/librte_compressdev/rte_comp.h index b7474c4..95306c5 100644 --- a/lib/librte_compressdev/rte_comp.h +++ b/lib/librte_compressdev/rte_comp.h @@ -323,6 +323,12 @@ struct rte_comp_op { * If the output data is expected to be bigger than this a chain of * mbufs can be passed to the PMD if the PMD's capabilities indicate * it supports this. + * + * @note, if incompressible data is passed to an engine for compression + * using RTE_COMP_ALGO_DEFLATE, it's possible for the output data + * to be larger than the uncompressed data, due to the inclusion + * of the DEFLATE header blocks. The size of m_dst should accommodate + * this, else OUT_OF_SPACE errors can be expected in this case. */ struct { -- 1.7.0.7