| Message ID | 20191229183341.14877-9-liuwe@microsoft.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | More Hyper-V infrastructure | expand |
From: Wei Liu <wei.liu.xen@gmail.com> On Behalf Of Wei Liu Sent: Sunday, December 29, 2019 10:34 AM > > VP assist page is rather important as we need to toggle some bits in > that page such that L1 guest can make hypercalls directly to L0 Hyper-V. > > Preemptively split out set_vp_assist page which will be used in the resume > path. > > Signed-off-by: Wei Liu <liuwe@microsoft.com> > --- > xen/arch/x86/guest/hyperv/hyperv.c | 35 ++++++++++++++++++++++++++++++ > xen/include/asm-x86/guest/hyperv.h | 1 + > 2 files changed, 36 insertions(+) > > diff --git a/xen/arch/x86/guest/hyperv/hyperv.c b/xen/arch/x86/guest/hyperv/hyperv.c > index da3a8cd85d..a88b9ae6d9 100644 > --- a/xen/arch/x86/guest/hyperv/hyperv.c > +++ b/xen/arch/x86/guest/hyperv/hyperv.c > @@ -30,6 +30,7 @@ void *hv_hypercall; > static struct page_info *hv_hypercall_page; > DEFINE_PER_CPU_READ_MOSTLY(struct hyperv_pcpu_page, hv_pcpu_input_arg); > DEFINE_PER_CPU_READ_MOSTLY(unsigned int, hv_vp_index); > +DEFINE_PER_CPU_READ_MOSTLY(struct hyperv_pcpu_page, hv_vp_assist); > > static const struct hypervisor_ops ops; > const struct hypervisor_ops *__init hyperv_probe(void) > @@ -125,17 +126,51 @@ static void setup_vp_index(void) > this_cpu(hv_vp_index) = vp_index_msr; > } > > +static void set_vp_assist(void) > +{ > + uint64_t val = paddr_to_pfn(this_cpu(hv_vp_assist).maddr); > + > + val = (val << HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_SHIFT) | I'd recommend using HV_HYP_PAGE_SHIFT instead of HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_SHIFT. On the Linux side, I'm planning to remove that #define and the similar *_PAGE_ADDRESS_MASK in favor of the newer HV_HYP_PAGE_* values. There's nothing special about the VP assist page, so using the generic #defines based on the Hyper-V page size is reasonable. Michael > + HV_X64_MSR_VP_ASSIST_PAGE_ENABLE; > + > + wrmsrl(HV_X64_MSR_VP_ASSIST_PAGE, val); > +} > + > +static void setup_vp_assist(void) > +{ > + struct page_info *pg; > + void *mapping; > + unsigned int cpu = smp_processor_id(); > + > + pg = alloc_domheap_page(NULL, 0); > + if ( !pg ) > + panic("Failed to allocate vp_assist page for %u\n", cpu); > + > + mapping = __map_domain_page_global(pg); > + if ( !mapping ) > + panic("Failed to map vp_assist page for %u\n", cpu); > + > + clear_page(mapping); > + > + this_cpu(hv_vp_assist).maddr = page_to_maddr(pg); > + this_cpu(hv_vp_assist).mapping = mapping; > + > + set_vp_assist(); > +} > + > static void __init setup(void) > { > setup_hypercall_page(); > setup_hypercall_pcpu_arg(); > setup_vp_index(); > + setup_vp_assist(); > } > > static void ap_setup(void) > { > setup_hypercall_pcpu_arg(); > setup_vp_index(); > + setup_vp_assist(); > } > > static const struct hypervisor_ops ops = { > diff --git a/xen/include/asm-x86/guest/hyperv.h b/xen/include/asm-x86/guest/hyperv.h > index 4b635829f3..917f4e02c2 100644 > --- a/xen/include/asm-x86/guest/hyperv.h > +++ b/xen/include/asm-x86/guest/hyperv.h > @@ -71,6 +71,7 @@ struct hyperv_pcpu_page { > }; > DECLARE_PER_CPU(struct hyperv_pcpu_page, hv_pcpu_input_arg); > DECLARE_PER_CPU(unsigned int, hv_vp_index); > +DECLARE_PER_CPU(struct hyperv_pcpu_page, hv_vp_assist); > > const struct hypervisor_ops *hyperv_probe(void); > > -- > 2.20.1
On Sun, Dec 29, 2019 at 07:59:48PM +0000, Michael Kelley wrote: > From: Wei Liu <wei.liu.xen@gmail.com> On Behalf Of Wei Liu Sent: Sunday, December 29, 2019 10:34 AM > > > > VP assist page is rather important as we need to toggle some bits in > > that page such that L1 guest can make hypercalls directly to L0 Hyper-V. > > > > Preemptively split out set_vp_assist page which will be used in the resume > > path. > > > > Signed-off-by: Wei Liu <liuwe@microsoft.com> > > --- > > xen/arch/x86/guest/hyperv/hyperv.c | 35 ++++++++++++++++++++++++++++++ > > xen/include/asm-x86/guest/hyperv.h | 1 + > > 2 files changed, 36 insertions(+) > > > > diff --git a/xen/arch/x86/guest/hyperv/hyperv.c b/xen/arch/x86/guest/hyperv/hyperv.c > > index da3a8cd85d..a88b9ae6d9 100644 > > --- a/xen/arch/x86/guest/hyperv/hyperv.c > > +++ b/xen/arch/x86/guest/hyperv/hyperv.c > > @@ -30,6 +30,7 @@ void *hv_hypercall; > > static struct page_info *hv_hypercall_page; > > DEFINE_PER_CPU_READ_MOSTLY(struct hyperv_pcpu_page, hv_pcpu_input_arg); > > DEFINE_PER_CPU_READ_MOSTLY(unsigned int, hv_vp_index); > > +DEFINE_PER_CPU_READ_MOSTLY(struct hyperv_pcpu_page, hv_vp_assist); > > > > static const struct hypervisor_ops ops; > > const struct hypervisor_ops *__init hyperv_probe(void) > > @@ -125,17 +126,51 @@ static void setup_vp_index(void) > > this_cpu(hv_vp_index) = vp_index_msr; > > } > > > > +static void set_vp_assist(void) > > +{ > > + uint64_t val = paddr_to_pfn(this_cpu(hv_vp_assist).maddr); > > + > > + val = (val << HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_SHIFT) | > > I'd recommend using HV_HYP_PAGE_SHIFT instead of > HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_SHIFT. On the Linux side, > I'm planning to remove that #define and the similar > *_PAGE_ADDRESS_MASK in favor of the newer HV_HYP_PAGE_* values. > There's nothing special about the VP assist page, so using the generic > #defines based on the Hyper-V page size is reasonable. Ack. Wei.
diff --git a/xen/arch/x86/guest/hyperv/hyperv.c b/xen/arch/x86/guest/hyperv/hyperv.c index da3a8cd85d..a88b9ae6d9 100644 --- a/xen/arch/x86/guest/hyperv/hyperv.c +++ b/xen/arch/x86/guest/hyperv/hyperv.c @@ -30,6 +30,7 @@ void *hv_hypercall; static struct page_info *hv_hypercall_page; DEFINE_PER_CPU_READ_MOSTLY(struct hyperv_pcpu_page, hv_pcpu_input_arg); DEFINE_PER_CPU_READ_MOSTLY(unsigned int, hv_vp_index); +DEFINE_PER_CPU_READ_MOSTLY(struct hyperv_pcpu_page, hv_vp_assist); static const struct hypervisor_ops ops; const struct hypervisor_ops *__init hyperv_probe(void) @@ -125,17 +126,51 @@ static void setup_vp_index(void) this_cpu(hv_vp_index) = vp_index_msr; } +static void set_vp_assist(void) +{ + uint64_t val = paddr_to_pfn(this_cpu(hv_vp_assist).maddr); + + val = (val << HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_SHIFT) | + HV_X64_MSR_VP_ASSIST_PAGE_ENABLE; + + wrmsrl(HV_X64_MSR_VP_ASSIST_PAGE, val); +} + +static void setup_vp_assist(void) +{ + struct page_info *pg; + void *mapping; + unsigned int cpu = smp_processor_id(); + + pg = alloc_domheap_page(NULL, 0); + if ( !pg ) + panic("Failed to allocate vp_assist page for %u\n", cpu); + + mapping = __map_domain_page_global(pg); + if ( !mapping ) + panic("Failed to map vp_assist page for %u\n", cpu); + + clear_page(mapping); + + this_cpu(hv_vp_assist).maddr = page_to_maddr(pg); + this_cpu(hv_vp_assist).mapping = mapping; + + set_vp_assist(); +} + static void __init setup(void) { setup_hypercall_page(); setup_hypercall_pcpu_arg(); setup_vp_index(); + setup_vp_assist(); } static void ap_setup(void) { setup_hypercall_pcpu_arg(); setup_vp_index(); + setup_vp_assist(); } static const struct hypervisor_ops ops = { diff --git a/xen/include/asm-x86/guest/hyperv.h b/xen/include/asm-x86/guest/hyperv.h index 4b635829f3..917f4e02c2 100644 --- a/xen/include/asm-x86/guest/hyperv.h +++ b/xen/include/asm-x86/guest/hyperv.h @@ -71,6 +71,7 @@ struct hyperv_pcpu_page { }; DECLARE_PER_CPU(struct hyperv_pcpu_page, hv_pcpu_input_arg); DECLARE_PER_CPU(unsigned int, hv_vp_index); +DECLARE_PER_CPU(struct hyperv_pcpu_page, hv_vp_assist); const struct hypervisor_ops *hyperv_probe(void);
VP assist page is rather important as we need to toggle some bits in that page such that L1 guest can make hypercalls directly to L0 Hyper-V. Preemptively split out set_vp_assist page which will be used in the resume path. Signed-off-by: Wei Liu <liuwe@microsoft.com> --- xen/arch/x86/guest/hyperv/hyperv.c | 35 ++++++++++++++++++++++++++++++ xen/include/asm-x86/guest/hyperv.h | 1 + 2 files changed, 36 insertions(+)