Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755566Ab3I3RWo (ORCPT ); Mon, 30 Sep 2013 13:22:44 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:39698 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754842Ab3I3RWn (ORCPT ); Mon, 30 Sep 2013 13:22:43 -0400 Date: Mon, 30 Sep 2013 13:22:09 -0400 From: Konrad Rzeszutek Wilk To: Stefano Stabellini Cc: xen-devel@lists.xensource.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Ian.Campbell@citrix.com Subject: Re: [PATCH v6 17/19] xen: introduce XENMEM_pin Message-ID: <20130930172209.GX3106@phenom.dumpdata.com> References: <1380298207-29151-17-git-send-email-stefano.stabellini@eu.citrix.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1380298207-29151-17-git-send-email-stefano.stabellini@eu.citrix.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-Source-IP: acsinet21.oracle.com [141.146.126.237] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4345 Lines: 126 On Fri, Sep 27, 2013 at 05:10:05PM +0100, Stefano Stabellini wrote: > Introduce a new hypercall to pin one or more pages whose machine > addresses respect a dma_mask passed as an argument > > Signed-off-by: Stefano Stabellini > --- > arch/arm/xen/mm.c | 16 ++++++++++++++++ > arch/x86/xen/mmu.c | 7 +++++++ > include/xen/interface/memory.h | 32 ++++++++++++++++++++++++++++++++ > include/xen/xen-ops.h | 1 + > 4 files changed, 56 insertions(+), 0 deletions(-) > > diff --git a/arch/arm/xen/mm.c b/arch/arm/xen/mm.c > index b305b94..146c1c3 100644 > --- a/arch/arm/xen/mm.c > +++ b/arch/arm/xen/mm.c > @@ -55,6 +55,22 @@ static int xen_exchange_memory(xen_ulong_t extents_in, > return success; > } > > +int xen_pin_page(xen_pfn_t *in_frame, unsigned int address_bits) > +{ > + struct xen_pin pin = { > + .in = { > + .nr_extents = 1, > + .extent_order = 0, > + .domid = DOMID_SELF, > + .address_bits = address_bits > + }, > + }; > + set_xen_guest_handle(pin.in.extent_start, in_frame); > + > + return HYPERVISOR_memory_op(XENMEM_pin, &pin); > +} > +EXPORT_SYMBOL_GPL(xen_pin_page); > + > int xen_create_contiguous_region(phys_addr_t pstart, unsigned int order, > unsigned int address_bits, > dma_addr_t *dma_handle) > diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c > index 8830883..8f76ce2 100644 > --- a/arch/x86/xen/mmu.c > +++ b/arch/x86/xen/mmu.c > @@ -2568,3 +2568,10 @@ int xen_unmap_domain_mfn_range(struct vm_area_struct *vma, > return -EINVAL; > } > EXPORT_SYMBOL_GPL(xen_unmap_domain_mfn_range); > + > +int xen_pin_page(xen_pfn_t *in_frame, unsigned int address_bits) > +{ > + return -ENOSYS; > +} > +EXPORT_SYMBOL_GPL(xen_pin_page); > + > diff --git a/include/xen/interface/memory.h b/include/xen/interface/memory.h > index 49db252..66ab578 100644 > --- a/include/xen/interface/memory.h > +++ b/include/xen/interface/memory.h > @@ -314,4 +314,36 @@ struct xen_unpin { > }; > DEFINE_GUEST_HANDLE_STRUCT(xen_unpin); > > +/* > + * XENMEM_pin pins a set of pages to make sure that the hypervisor does > + * not change the p2m mappings for them. > + * > + */ > +#define XENMEM_pin 28 > +struct xen_pin { > + /* > + * [IN/OUT] Details of memory extents to be pinned (GMFN bases). > + * Xen copies back the MFNs corresponding to the GMFNs passed in as > + * argument. > + * @in.address_bits contains the maximum number of bits addressable > + * by the caller. If the machine addresses of the pages to be pinned > + * are not addressable according to @in.address_bits, the hypercall > + * fails and returns an errors. The pages are not pinned. Otherwise ^^^^^-error. What kind of error? And you should probably join the two sentences together (the "If the ... The pages are not pinned.") > + * the hypercall succeeds. and does it return a number of pages that were pinned or just zero? > + */ > + struct xen_memory_reservation in; > + > + /* > + * [OUT] Number of input extents that were successfully pinned. > + * 1. The first @nr_pinned input extents were successfully > + * pinned. > + * 2. All other input extents are untouched. > + * 3. If not all input extents are pinned then the return code of this > + * command will be non-zero. OK, what return code? > + */ > + xen_ulong_t nr_pinned; > +}; > +DEFINE_GUEST_HANDLE_STRUCT(xen_pin); > + > + > #endif /* __XEN_PUBLIC_MEMORY_H__ */ > diff --git a/include/xen/xen-ops.h b/include/xen/xen-ops.h > index fb2ea8f..4cf4fc5 100644 > --- a/include/xen/xen-ops.h > +++ b/include/xen/xen-ops.h > @@ -22,6 +22,7 @@ extern unsigned long *xen_contiguous_bitmap; > int xen_create_contiguous_region(phys_addr_t pstart, unsigned int order, > unsigned int address_bits, > dma_addr_t *dma_handle); > +int xen_pin_page(xen_pfn_t *in_frame, unsigned int address_bits); > > void xen_destroy_contiguous_region(phys_addr_t pstart, unsigned int order); > > -- > 1.7.2.5 > -- 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/