Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753725Ab3HAAgq (ORCPT ); Wed, 31 Jul 2013 20:36:46 -0400 Received: from userp1040.oracle.com ([156.151.31.81]:36434 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752734Ab3HAAgn convert rfc822-to-8bit (ORCPT ); Wed, 31 Jul 2013 20:36:43 -0400 User-Agent: K-9 Mail for Android In-Reply-To: <1375292732-7627-5-git-send-email-stefano.stabellini@eu.citrix.com> References: <1375292732-7627-5-git-send-email-stefano.stabellini@eu.citrix.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8BIT Content-Type: text/plain; charset=UTF-8 Subject: Re: [PATCH RFC 5/8] xen: introduce XENMEM_get_dma_buf and xen_put_dma_buf From: Konrad Rzeszutek Wilk Date: Wed, 31 Jul 2013 20:36:03 -0400 To: Stefano Stabellini , xen-devel@lists.xensource.com CC: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Stefano.Stabellini@eu.citrix.com, Ian.Campbell@citrix.com Message-ID: <22032fc7-81f5-4271-81b6-cd2bee277fb5@email.android.com> X-Source-IP: ucsinet21.oracle.com [156.151.31.93] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3553 Lines: 98 Stefano Stabellini wrote: >Signed-off-by: Stefano Stabellini >--- >include/xen/interface/memory.h | 62 >++++++++++++++++++++++++++++++++++++++++ > 1 files changed, 62 insertions(+), 0 deletions(-) > >diff --git a/include/xen/interface/memory.h >b/include/xen/interface/memory.h >index 2ecfe4f..ffd7f4e 100644 >--- a/include/xen/interface/memory.h >+++ b/include/xen/interface/memory.h >@@ -263,4 +263,66 @@ struct xen_remove_from_physmap { > }; > DEFINE_GUEST_HANDLE_STRUCT(xen_remove_from_physmap); > >+#define XENMEM_get_dma_buf 26 >+/* >+ * This hypercall is similar to XENMEM_exchange: it exchanges the >pages Could you elaborate why the existing hyper call won't work? >+ * passed in with a new set of pages, contiguous and under 4G if so >+ * requested. The new pages are going to be "pinned": it's guaranteed >+ * that their p2m mapping won't be changed until explicitly >"unpinned". >+ * If return code is zero then @out.extent_list provides the MFNs of >the >+ * newly-allocated memory. Returns zero on complete success, >otherwise >+ * a negative error code. >+ * On complete success then always @nr_exchanged == @in.nr_extents. >On >+ * partial success @nr_exchanged indicates how much work was done. >+ */ >+struct xen_get_dma_buf { >+ /* >+ * [IN] Details of memory extents to be exchanged (GMFN bases). >+ * Note that @in.address_bits is ignored and unused. >+ */ >+ struct xen_memory_reservation in; >+ >+ /* >+ * [IN/OUT] Details of new memory extents. >+ * We require that: >+ * 1. @in.domid == @out.domid >+ * 2. @in.nr_extents << @in.extent_order == >+ * @out.nr_extents << @out.extent_order >+ * 3. @in.extent_start and @out.extent_start lists must not >overlap >+ * 4. @out.extent_start lists GPFN bases to be populated >+ * 5. @out.extent_start is overwritten with allocated GMFN bases >+ */ >+ struct xen_memory_reservation out; >+ >+ /* >+ * [OUT] Number of input extents that were successfully exchanged: >+ * 1. The first @nr_exchanged input extents were successfully >+ * deallocated. >+ * 2. The corresponding first entries in the output extent list >correctly >+ * indicate the GMFNs that were successfully exchanged. >+ * 3. All other input and output extents are untouched. >+ * 4. If not all input exents are exchanged then the return code >of this >+ * command will be non-zero. >+ * 5. THIS FIELD MUST BE INITIALISED TO ZERO BY THE CALLER! >+ */ >+ xen_ulong_t nr_exchanged; >+}; >+DEFINE_GUEST_HANDLE_STRUCT(xen_get_dma_buf); >+ >+#define XENMEM_put_dma_buf 27 >+/* >+ * XENMEM_put_dma_buf unpins a set of pages, previously pinned by >+ * XENMEM_get_dma_buf. After this call the p2m mapping of the pages >can >+ * be transparently changed by the hypervisor, as usual. The pages are >+ * still accessible from the guest. >+ */ >+struct xen_put_dma_buf { >+ /* >+ * [IN] Details of memory extents to be exchanged (GMFN bases). >+ * Note that @in.address_bits is ignored and unused. >+ */ >+ struct xen_memory_reservation in; >+}; >+DEFINE_GUEST_HANDLE_STRUCT(xen_put_dma_buf); >+ > #endif /* __XEN_PUBLIC_MEMORY_H__ */ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/