Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757048Ab2JSNTu (ORCPT ); Fri, 19 Oct 2012 09:19:50 -0400 Received: from rcsinet15.oracle.com ([148.87.113.117]:40643 "EHLO rcsinet15.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751780Ab2JSNTt (ORCPT ); Fri, 19 Oct 2012 09:19:49 -0400 Date: Fri, 19 Oct 2012 09:07:39 -0400 From: Konrad Rzeszutek Wilk To: Mukesh Rathor Cc: "Xen-devel@lists.xensource.com" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH V3 1/6]: PVH: basic and header changes, elfnote changes, ... Message-ID: <20121019130739.GF26830@phenom.dumpdata.com> References: <20121017172642.349b2aae@mantra.us.oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20121017172642.349b2aae@mantra.us.oracle.com> User-Agent: Mutt/1.5.21 (2010-09-15) 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: 6479 Lines: 165 On Wed, Oct 17, 2012 at 05:26:42PM -0700, Mukesh Rathor wrote: > [PATCH 1/6] PVH: is a PV linux guest that has extended capabilities. This patch allows it to be configured and enabled. Also, basic header file changes to add new subcalls to physmap hypercall. Lastly, mfn_to_local_pfn must return mfn for paging mode translate. Usually one splits that description. So you have: (for title) "xen/pvh: Introduce ParaVirtualized Hardware support." And then in the body do (and split it in 80 lines for easier readability): ParaVirtualized Hardware (PVH) support allows a PV linux guest that has extended capabilities. [Q:Like what kind of extended capabilities? Can you explain what they are?] This patch allows it to be configured and enabled. Also, basic header file changes to add new subcalls to physmap hypercall. Lastly, mfn_to_local_pfn must return mfn for paging mode translate. [Q: You should explain why. There is nothing in this description saying why we do not need the PV MMU anymore] [note: the verb tense is wrong since I meshed your description with mine, so it would have to be fixed] > > Signed-off-by: Mukesh Rathor > --- > arch/x86/include/asm/xen/page.h | 3 +++ > arch/x86/xen/Kconfig | 10 ++++++++++ > arch/x86/xen/xen-head.S | 11 ++++++++++- > include/xen/interface/memory.h | 24 +++++++++++++++++++++++- > include/xen/interface/physdev.h | 10 ++++++++++ > 5 files changed, 56 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/include/asm/xen/page.h b/arch/x86/include/asm/xen/page.h > index 472b9b7..6af440d 100644 > --- a/arch/x86/include/asm/xen/page.h > +++ b/arch/x86/include/asm/xen/page.h > @@ -159,6 +159,9 @@ static inline xpaddr_t machine_to_phys(xmaddr_t machine) > static inline unsigned long mfn_to_local_pfn(unsigned long mfn) > { > unsigned long pfn = mfn_to_pfn(mfn); > + > + if (xen_feature(XENFEAT_auto_translated_physmap)) > + return mfn; > if (get_phys_to_machine(pfn) != mfn) > return -1; /* force !pfn_valid() */ > return pfn; > diff --git a/arch/x86/xen/Kconfig b/arch/x86/xen/Kconfig > index fdce49c..822c5a0 100644 > --- a/arch/x86/xen/Kconfig > +++ b/arch/x86/xen/Kconfig > @@ -50,3 +50,13 @@ config XEN_DEBUG_FS > Enable statistics output and various tuning options in debugfs. > Enabling this option may incur a significant performance overhead. > > +config XEN_X86_PVH > + bool "Support for running as a PVH guest (EXPERIMENTAL)" > + depends on X86_64 && XEN && EXPERIMENTAL > + default n > + help > + This option enables support for running as a PVH guest (PV guest > + using hardware extensions) under a suitably capable hypervisor. > + This option is EXPERIMENTAL because the hypervisor interfaces > + which it uses are not yet considered stable therefore backwards and > + forwards compatibility is not yet guaranteed. If unsure, say N. > diff --git a/arch/x86/xen/xen-head.S b/arch/x86/xen/xen-head.S > index 7faed58..1a6bca1 100644 > --- a/arch/x86/xen/xen-head.S > +++ b/arch/x86/xen/xen-head.S > @@ -13,6 +13,15 @@ > #include > #include > > +#ifdef CONFIG_XEN_X86_PVH > +#define FEATURES_PVH "|writable_descriptor_tables" \ > + "|auto_translated_physmap" \ > + "|supervisor_mode_kernel" \ > + "|hvm_callback_vector" > +#else > +#define FEATURES_PVH /* Not supported */ > +#endif > + > __INIT > ENTRY(startup_xen) > cld > @@ -95,7 +104,7 @@ NEXT_HYPERCALL(arch_6) > #endif > ELFNOTE(Xen, XEN_ELFNOTE_ENTRY, _ASM_PTR startup_xen) > ELFNOTE(Xen, XEN_ELFNOTE_HYPERCALL_PAGE, _ASM_PTR hypercall_page) > - ELFNOTE(Xen, XEN_ELFNOTE_FEATURES, .asciz "!writable_page_tables|pae_pgdir_above_4gb") > + ELFNOTE(Xen, XEN_ELFNOTE_FEATURES, .asciz "!writable_page_tables|pae_pgdir_above_4gb"FEATURES_PVH) > ELFNOTE(Xen, XEN_ELFNOTE_PAE_MODE, .asciz "yes") > ELFNOTE(Xen, XEN_ELFNOTE_LOADER, .asciz "generic") > ELFNOTE(Xen, XEN_ELFNOTE_L1_MFN_VALID, > diff --git a/include/xen/interface/memory.h b/include/xen/interface/memory.h > index d8e33a9..425911f 100644 > --- a/include/xen/interface/memory.h > +++ b/include/xen/interface/memory.h > @@ -169,7 +169,13 @@ struct xen_add_to_physmap { > /* Source mapping space. */ > #define XENMAPSPACE_shared_info 0 /* shared info page */ > #define XENMAPSPACE_grant_table 1 /* grant table page */ > - unsigned int space; > +#define XENMAPSPACE_gmfn 2 /* GMFN */ > +#define XENMAPSPACE_gmfn_range 3 /* GMFN range */ > +#define XENMAPSPACE_gmfn_foreign 4 /* GMFN from another guest */ > + uint16_t space; > + domid_t foreign_domid; /* IFF XENMAPSPACE_gmfn_foreign */ > + > +#define XENMAPIDX_grant_table_status 0x80000000 > > /* Index into source mapping space. */ > unsigned long idx; > @@ -237,4 +243,20 @@ DEFINE_GUEST_HANDLE_STRUCT(xen_memory_map); > * during a driver critical region. > */ > extern spinlock_t xen_reservation_lock; > + > +/* > + * Unmaps the page appearing at a particular GPFN from the specified guest's > + * pseudophysical address space. > + * arg == addr of xen_remove_from_physmap_t. > + */ > +#define XENMEM_remove_from_physmap 15 > +struct xen_remove_from_physmap { > + /* Which domain to change the mapping for. */ > + domid_t domid; > + > + /* GPFN of the current mapping of the page. */ > + xen_pfn_t gpfn; > +}; > +DEFINE_GUEST_HANDLE_STRUCT(xen_remove_from_physmap); > + > #endif /* __XEN_PUBLIC_MEMORY_H__ */ > diff --git a/include/xen/interface/physdev.h b/include/xen/interface/physdev.h > index 9ce788d..3b9d5b6 100644 > --- a/include/xen/interface/physdev.h > +++ b/include/xen/interface/physdev.h > @@ -258,6 +258,16 @@ struct physdev_pci_device { > uint8_t devfn; > }; > > +#define PHYSDEVOP_pvh_map_iomem 30 > +struct physdev_map_iomem { > + /* IN */ > + uint64_t first_gfn; > + uint64_t first_mfn; > + uint32_t nr_mfns; > + uint32_t add_mapping; /* 1 == add mapping; 0 == unmap */ > + > +}; > + > /* > * Notify that some PIRQ-bound event channels have been unmasked. > * ** This command is obsolete since interface version 0x00030202 and is ** > -- > 1.7.2.3 -- 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/