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 3B746A052A; Fri, 10 Jul 2020 17:39:11 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id B2D691DAAB; Fri, 10 Jul 2020 17:39:10 +0200 (CEST) Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by dpdk.org (Postfix) with ESMTP id 450681DAAA for ; Fri, 10 Jul 2020 17:39:09 +0200 (CEST) IronPort-SDR: ugo6JBFds6Rxy7aWOHxm5cARM7CvTOOhNHBCUQqbUMebHZzKRjWYCXIuvuw4fuwdifhGREdaOg 0OBn6/hmNC9A== X-IronPort-AV: E=McAfee;i="6000,8403,9678"; a="136425630" X-IronPort-AV: E=Sophos;i="5.75,336,1589266800"; d="scan'208";a="136425630" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga006.jf.intel.com ([10.7.209.51]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Jul 2020 08:39:08 -0700 IronPort-SDR: E25RqNkSDDS/Z6zyHaugS8hL3H0aixzu+472Zxvp20mXrhJGUOoazc/0TKjCzQXODTqclVZWIm 4f0HK9h0LpMw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.75,336,1589266800"; d="scan'208";a="284539199" Received: from aburakov-mobl.ger.corp.intel.com (HELO [10.213.1.123]) ([10.213.1.123]) by orsmga006.jf.intel.com with ESMTP; 10 Jul 2020 08:39:03 -0700 To: Thomas Monjalon , dev@dpdk.org Cc: david.marchand@redhat.com, ferruh.yigit@intel.com, grive@u256.net, alvinx.zhang@intel.com, beilei.xing@intel.com, jia.guo@intel.com, bruce.richardson@intel.com, dmitry.kozliuk@gmail.com, navasile@linux.microsoft.com, dmitrym@microsoft.com, pallavi.kadam@intel.com, talshn@mellanox.com References: <20200710115324.3902559-1-thomas@monjalon.net> From: "Burakov, Anatoly" Message-ID: <3151e427-77af-80c0-e53b-4e107bb1a40c@intel.com> Date: Fri, 10 Jul 2020 16:39:02 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.9.0 MIME-Version: 1.0 In-Reply-To: <20200710115324.3902559-1-thomas@monjalon.net> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Subject: Re: [dpdk-dev] [PATCH] pci: keep API compatibility with mmap values 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" On 10-Jul-20 12:53 PM, Thomas Monjalon wrote: > The function pci_map_resource() returns MAP_FAILED in case of error. > When replacing the call to mmap() by rte_mem_map(), > the error code became NULL, breaking the API. > This function is probably not used outside of DPDK, > but it is still a problem for two reasons: > - the deprecation process was not followed > - the Linux function pci_vfio_mmap_bar() is broken for i40e > > The error code is reverted to the Unix value MAP_FAILED. > Windows needs to define this special value (-1 as in Unix). > After proper deprecation process, the API could be changed again > if really needed. > > Because of the switch from mmap() to rte_mem_map(), > another part of the API was changed: "int additional_flags" > are defined as "additional flags for the mapping range" > without mentioning it was directly used in mmap(). > Currently it is directly used in rte_mem_map(), > that's why the values rte_map_flags must be mapped (sic) on the mmap ones > in case of Unix OS. > > These are side effects of a badly defined API using Unix values. > > Bugzilla ID: 503 > Fixes: 2fd3567e5425 ("pci: use OS generic memory mapping functions") > Cc: talshn@mellanox.com > > Reported-by: David Marchand > Signed-off-by: Thomas Monjalon > --- > /* unmap addrs correctly mapped */ > for (j = 0; j < i; j++) > pci_unmap_resource( > diff --git a/lib/librte_eal/include/rte_eal_paging.h b/lib/librte_eal/include/rte_eal_paging.h > index ed98e70e9e..680a7f2505 100644 > --- a/lib/librte_eal/include/rte_eal_paging.h > +++ b/lib/librte_eal/include/rte_eal_paging.h > @@ -3,6 +3,7 @@ > */ > > #include > +#include > > #include > > @@ -22,6 +23,7 @@ enum rte_mem_prot { > > /** Additional flags for memory mapping. */ > enum rte_map_flags { > +#ifdef RTE_EXEC_ENV_WINDOWS > /** Changes to the mapped memory are visible to other processes. */ > RTE_MAP_SHARED = 1 << 0, > /** Mapping is not backed by a regular file. */ > @@ -35,6 +37,12 @@ enum rte_map_flags { > * it is not required to do so, thus mapping with this flag may fail. > */ > RTE_MAP_FORCE_ADDRESS = 1 << 3 > +#else /* map mmap flags because they are exposed in pci_map_resource() API */ > + RTE_MAP_SHARED = MAP_SHARED, > + RTE_MAP_ANONYMOUS = MAP_ANONYMOUS, > + RTE_MAP_PRIVATE = MAP_PRIVATE, > + RTE_MAP_FORCE_ADDRESS = MAP_FIXED, > +#endif I'm probably missing something, but why is this needed? Doesn't rte_mem_map() automatically translate these flags into proper ones? pci_map_resource() will call rte_mem_map(), and that will translate these flags into their Unix equivalents. -- Thanks, Anatoly