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=-11.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 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 EB52BC43461 for ; Tue, 8 Sep 2020 22:17:16 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 74ADC20936 for ; Tue, 8 Sep 2020 22:17:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 74ADC20936 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id 28F9186D80; Tue, 8 Sep 2020 22:17:16 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id tVb4A6OBdtiX; Tue, 8 Sep 2020 22:17:14 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by fraxinus.osuosl.org (Postfix) with ESMTP id BE35386D9D; Tue, 8 Sep 2020 22:17:14 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id A804FC0052; Tue, 8 Sep 2020 22:17:14 +0000 (UTC) Received: from whitealder.osuosl.org (smtp1.osuosl.org [140.211.166.138]) by lists.linuxfoundation.org (Postfix) with ESMTP id DD94EC0051 for ; Tue, 8 Sep 2020 22:17:13 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by whitealder.osuosl.org (Postfix) with ESMTP id D92CF86852 for ; Tue, 8 Sep 2020 22:17:13 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from whitealder.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id QogcUTw2WIfZ for ; Tue, 8 Sep 2020 22:17:12 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) by whitealder.osuosl.org (Postfix) with ESMTPS id 66076853C5 for ; Tue, 8 Sep 2020 22:17:12 +0000 (UTC) IronPort-SDR: 9ZLpOS/ZIXA/ltTV+6rh0YFqu5ss+Y3M2YqtfDZD8llo+CPlV5KnHtnJMOEm/QZb24XXmoeAwn IOLiEv6mA5gw== X-IronPort-AV: E=McAfee;i="6000,8403,9738"; a="138278313" X-IronPort-AV: E=Sophos;i="5.76,407,1592895600"; d="scan'208";a="138278313" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga006.jf.intel.com ([10.7.209.51]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Sep 2020 15:17:11 -0700 IronPort-SDR: wdfv1J+J+QaysLnpOhCWO81wvxM1SV7iRWPHywKC9WXHRhhsGc5OBo9wVFKCccOp7ltS7qufX/ dHiIu5NF2L3w== X-IronPort-AV: E=Sophos;i="5.76,407,1592895600"; d="scan'208";a="304259025" Received: from jacob-builder.jf.intel.com (HELO jacob-builder) ([10.7.199.155]) by orsmga006-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Sep 2020 15:17:11 -0700 Date: Tue, 8 Sep 2020 15:19:08 -0700 From: Jacob Pan To: Jean-Philippe Brucker Subject: Re: [PATCH v2 5/9] iommu/ioasid: Introduce ioasid_set private ID Message-ID: <20200908151908.37df01f1@jacob-builder> In-Reply-To: <20200825102209.GC3252704@myrica> References: <1598070918-21321-1-git-send-email-jacob.jun.pan@linux.intel.com> <1598070918-21321-6-git-send-email-jacob.jun.pan@linux.intel.com> <20200825102209.GC3252704@myrica> Organization: OTC X-Mailer: Claws Mail 3.13.2 (GTK+ 2.24.30; x86_64-pc-linux-gnu) MIME-Version: 1.0 Cc: "Tian, Kevin" , Jacob Pan , Raj Ashok , David Woodhouse , LKML , iommu@lists.linux-foundation.org, Jean-Philippe Brucker , Wu Hao X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On Tue, 25 Aug 2020 12:22:09 +0200 Jean-Philippe Brucker wrote: > On Fri, Aug 21, 2020 at 09:35:14PM -0700, Jacob Pan wrote: > > When an IOASID set is used for guest SVA, each VM will acquire its > > ioasid_set for IOASID allocations. IOASIDs within the VM must have a > > host/physical IOASID backing, mapping between guest and host IOASIDs can > > be non-identical. IOASID set private ID (SPID) is introduced in this > > patch to be used as guest IOASID. However, the concept of ioasid_set > > specific namespace is generic, thus named SPID. > > > > As SPID namespace is within the IOASID set, the IOASID core can provide > > lookup services at both directions. SPIDs may not be allocated when its > > IOASID is allocated, the mapping between SPID and IOASID is usually > > established when a guest page table is bound to a host PASID. > > > > Signed-off-by: Jacob Pan > > --- > > drivers/iommu/ioasid.c | 54 ++++++++++++++++++++++++++++++++++++++++++++++++++ > > include/linux/ioasid.h | 12 +++++++++++ > > 2 files changed, 66 insertions(+) > > > > diff --git a/drivers/iommu/ioasid.c b/drivers/iommu/ioasid.c > > index 5f31d63c75b1..c0aef38a4fde 100644 > > --- a/drivers/iommu/ioasid.c > > +++ b/drivers/iommu/ioasid.c > > @@ -21,6 +21,7 @@ enum ioasid_state { > > * struct ioasid_data - Meta data about ioasid > > * > > * @id: Unique ID > > + * @spid: Private ID unique within a set > > * @users Number of active users > > * @state Track state of the IOASID > > * @set Meta data of the set this IOASID belongs to > > @@ -29,6 +30,7 @@ enum ioasid_state { > > */ > > struct ioasid_data { > > ioasid_t id; > > + ioasid_t spid; > > struct ioasid_set *set; > > refcount_t users; > > enum ioasid_state state; > > @@ -326,6 +328,58 @@ int ioasid_attach_data(ioasid_t ioasid, void *data) > > EXPORT_SYMBOL_GPL(ioasid_attach_data); > > > > /** > > + * ioasid_attach_spid - Attach ioasid_set private ID to an IOASID > > + * > > + * @ioasid: the ID to attach > > + * @spid: the ioasid_set private ID of @ioasid > > + * > > + * For IOASID that is already allocated, private ID within the set can be > > + * attached via this API. Future lookup can be done via ioasid_find. > > via ioasid_find_by_spid()? > yes, will update. > > + */ > > +int ioasid_attach_spid(ioasid_t ioasid, ioasid_t spid) > > +{ > > + struct ioasid_data *ioasid_data; > > + int ret = 0; > > + > > + spin_lock(&ioasid_allocator_lock); > > + ioasid_data = xa_load(&active_allocator->xa, ioasid); > > + > > + if (!ioasid_data) { > > + pr_err("No IOASID entry %d to attach SPID %d\n", > > + ioasid, spid); > > + ret = -ENOENT; > > + goto done_unlock; > > + } > > + ioasid_data->spid = spid; > > + > > +done_unlock: > > + spin_unlock(&ioasid_allocator_lock); > > + return ret; > > +} > > +EXPORT_SYMBOL_GPL(ioasid_attach_spid); > > + > > +ioasid_t ioasid_find_by_spid(struct ioasid_set *set, ioasid_t spid) > > Maybe add a bit of documentation as this is public-facing. > Good point, I will add /** * ioasid_find_by_spid - Find the system-wide IOASID by a set private ID and * its set. * * @set: the ioasid_set to search within * @spid: the set private ID * * Given a set private ID and its IOASID set, find the system-wide IOASID. Take * a reference upon finding the matching IOASID. Return INVALID_IOASID if the * IOASID is not found in the set or the set is not valid. */ > > +{ > > + struct ioasid_data *entry; > > + unsigned long index; > > + > > + if (!xa_load(&ioasid_sets, set->sid)) { > > + pr_warn("Invalid set\n"); > > + return INVALID_IOASID; > > + } > > + > > + xa_for_each(&set->xa, index, entry) { > > + if (spid == entry->spid) { > > + pr_debug("Found ioasid %lu by spid %u\n", index, spid); > > + refcount_inc(&entry->users); > > Nothing prevents ioasid_free() from concurrently dropping the refcount to > zero and calling ioasid_do_free(). The caller will later call ioasid_put() > on a stale/reallocated index. > right, need to add spin_lock(&ioasid_allocator_lock); > > + return index; > > + } > > + } > > + return INVALID_IOASID; > > +} > > +EXPORT_SYMBOL_GPL(ioasid_find_by_spid); > > + > > +/** > > * ioasid_alloc - Allocate an IOASID > > * @set: the IOASID set > > * @min: the minimum ID (inclusive) > > diff --git a/include/linux/ioasid.h b/include/linux/ioasid.h > > index 310abe4187a3..d4b3e83672f6 100644 > > --- a/include/linux/ioasid.h > > +++ b/include/linux/ioasid.h > > @@ -73,6 +73,8 @@ bool ioasid_is_active(ioasid_t ioasid); > > > > void *ioasid_find(struct ioasid_set *set, ioasid_t ioasid, bool (*getter)(void *)); > > int ioasid_attach_data(ioasid_t ioasid, void *data); > > +int ioasid_attach_spid(ioasid_t ioasid, ioasid_t spid); > > +ioasid_t ioasid_find_by_spid(struct ioasid_set *set, ioasid_t spid); > > int ioasid_register_allocator(struct ioasid_allocator_ops *allocator); > > void ioasid_unregister_allocator(struct ioasid_allocator_ops *allocator); > > void ioasid_is_in_set(struct ioasid_set *set, ioasid_t ioasid); > > @@ -136,5 +138,15 @@ static inline int ioasid_attach_data(ioasid_t ioasid, void *data) > > return -ENOTSUPP; > > } > > > > +staic inline int ioasid_attach_spid(ioasid_t ioasid, ioasid_t spid) > > +{ > > + return -ENOTSUPP; > > +} > > + > > +static inline ioasid_t ioasid_find_by_spid(struct ioasid_set *set, ioasid_t spid) > > +{ > > + return -ENOTSUPP; > > INVALID_IOASID > right, will fix. Thanks! > Thanks, > Jean > > > +} > > + > > #endif /* CONFIG_IOASID */ > > #endif /* __LINUX_IOASID_H */ > > -- > > 2.7.4 > > > _______________________________________________ > iommu mailing list > iommu@lists.linux-foundation.org > https://lists.linuxfoundation.org/mailman/listinfo/iommu [Jacob Pan] _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu