From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933264Ab1LFK52 (ORCPT ); Tue, 6 Dec 2011 05:57:28 -0500 Received: from acsinet15.oracle.com ([141.146.126.227]:28596 "EHLO acsinet15.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933089Ab1LFK51 (ORCPT ); Tue, 6 Dec 2011 05:57:27 -0500 From: annie.li@oracle.com To: xen-devel@lists.xensource.com, linux-kernel@vger.kernel.org, konrad.wilk@oracle.com, jeremy@goop.org Cc: kurt.hackel@oracle.com, paul.durrant@citrix.com, Ian.Campbell@citrix.com, annie.li@oracle.com Subject: [PATCH 2/2] xen/granttable: Support transitive grants Date: Tue, 6 Dec 2011 18:57:23 +0800 Message-Id: <1323169043-4470-1-git-send-email-annie.li@oracle.com> X-Mailer: git-send-email 1.7.6.4 In-Reply-To: <4EDDF41E.8070200@oracle.com> References: <4EDDF41E.8070200@oracle.com> X-Source-IP: ucsinet22.oracle.com [156.151.31.94] X-CT-RefId: str=0001.0A090204.4EDDF514.0037,ss=1,re=0.000,fgs=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Annie Li These allow a domain A which has been granted access on a page of domain B's memory to issue domain C with a copy-grant on the same page. This is useful e.g. for forwarding packets between domains. Signed-off-by: Annie Li --- drivers/xen/grant-table.c | 33 +++++++++++++++++++++++++++++++++ include/xen/grant_table.h | 6 ++++++ 2 files changed, 39 insertions(+), 0 deletions(-) diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c index 7a0f4d1..d64b7c5 100644 --- a/drivers/xen/grant-table.c +++ b/drivers/xen/grant-table.c @@ -296,6 +296,39 @@ void gnttab_grant_foreign_access_ref_subpage_v2(grant_ref_t ref, domid_t domid, } EXPORT_SYMBOL_GPL(gnttab_grant_foreign_access_ref_subpage_v2); +int gnttab_grant_foreign_access_trans_v2(domid_t domid, int flags, + domid_t trans_domid, + grant_ref_t trans_gref) +{ + int ref; + + ref = get_free_entries(1); + if (unlikely(ref < 0)) + return -ENOSPC; + + gnttab_grant_foreign_access_ref_trans_v2(ref, domid, flags, + trans_domid, trans_gref); + + return ref; +} +EXPORT_SYMBOL_GPL(gnttab_grant_foreign_access_trans_v2); + +void gnttab_grant_foreign_access_ref_trans_v2(grant_ref_t ref, domid_t domid, + int flags, domid_t trans_domid, + grant_ref_t trans_gref) +{ + BUG_ON(flags & (GTF_accept_transfer | GTF_reading | + GTF_writing | GTF_sub_page)); + BUG_ON(grant_table_version == 1); + gnttab_shared.v2[ref].transitive.trans_domid = trans_domid; + gnttab_shared.v2[ref].transitive.gref = trans_gref; + gnttab_shared.v2[ref].hdr.domid = domid; + wmb(); + gnttab_shared.v2[ref].hdr.flags = + GTF_permit_access | GTF_transitive | flags; +} +EXPORT_SYMBOL_GPL(gnttab_grant_foreign_access_ref_trans_v2); + bool gnttab_subpage_trans_grants_available(void) { return grant_table_version == 2; diff --git a/include/xen/grant_table.h b/include/xen/grant_table.h index 7e43652..35a8c73 100644 --- a/include/xen/grant_table.h +++ b/include/xen/grant_table.h @@ -65,6 +65,9 @@ int gnttab_grant_foreign_access(domid_t domid, unsigned long frame, int gnttab_grant_foreign_access_subpage_v2(domid_t domid, unsigned long frame, int flags, unsigned page_off, unsigned length); +int gnttab_grant_foreign_access_trans_v2(domid_t domid, int flags, + domid_t trans_domid, + grant_ref_t trans_gref); /* * Are sub-page or transitive grants available on this version of Xen? Returns @@ -121,6 +124,9 @@ void gnttab_grant_foreign_access_ref_subpage_v2(grant_ref_t ref, domid_t domid, unsigned long frame, int flags, unsigned page_off, unsigned length); +void gnttab_grant_foreign_access_ref_trans_v2(grant_ref_t ref, domid_t domid, + int flags, domid_t trans_domid, + grant_ref_t trans_gref); void gnttab_grant_foreign_transfer_ref(grant_ref_t, domid_t domid, unsigned long pfn); -- 1.7.6.4