| Message ID | 1635264312-3796-3-git-send-email-olekstysh@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | xen: Add support of extended regions (safe ranges) on Arm | expand |
On Tue, 26 Oct 2021, Oleksandr Tyshchenko wrote: > From: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> > > Read the start address of the grant table space from DT > (region 0). > > This patch mostly restores behaviour before commit 3cf4095d7446 > ("arm/xen: Use xen_xlate_map_ballooned_pages to setup grant table") > but trying not to break the ACPI support added after that commit. > So the patch touches DT part only and leaves the ACPI part with > xen_xlate_map_ballooned_pages(). > > This is a preparation for using Xen extended region feature > where unused regions of guest physical address space (provided > by the hypervisor) will be used to create grant/foreign/whatever > mappings instead of wasting real RAM pages from the domain memory > for establishing these mappings. > > The immediate benefit of this change: > - Avoid superpage shattering in Xen P2M when establishing > stage-2 mapping (GFN <-> MFN) for the grant table space > - Avoid wasting real RAM pages (reducing the amount of memory > usuable) for mapping grant table space > - The grant table space is always mapped at the exact > same place (region 0 is reserved for the grant table) > > Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> > --- > Changes RFC -> V2: > - new patch > --- > arch/arm/xen/enlighten.c | 32 +++++++++++++++++++++++++------- > 1 file changed, 25 insertions(+), 7 deletions(-) > > diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c > index 7f1c106b..dea46ec 100644 > --- a/arch/arm/xen/enlighten.c > +++ b/arch/arm/xen/enlighten.c > @@ -59,6 +59,9 @@ unsigned long xen_released_pages; > struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata; > > static __read_mostly unsigned int xen_events_irq; > +static phys_addr_t xen_grant_frames; __read_mostly > +#define GRANT_TABLE_INDEX 0 > > uint32_t xen_start_flags; > EXPORT_SYMBOL(xen_start_flags); > @@ -303,6 +306,7 @@ static void __init xen_acpi_guest_init(void) > static void __init xen_dt_guest_init(void) > { > struct device_node *xen_node; > + struct resource res; > > xen_node = of_find_compatible_node(NULL, NULL, "xen,xen"); > if (!xen_node) { > @@ -310,6 +314,12 @@ static void __init xen_dt_guest_init(void) > return; > } > > + if (of_address_to_resource(xen_node, GRANT_TABLE_INDEX, &res)) { > + pr_err("Xen grant table region is not found\n"); > + return; > + } > + xen_grant_frames = res.start; > + > xen_events_irq = irq_of_parse_and_map(xen_node, 0); > } > > @@ -317,16 +327,20 @@ static int __init xen_guest_init(void) > { > struct xen_add_to_physmap xatp; > struct shared_info *shared_info_page = NULL; > - int cpu; > + int rc, cpu; > > if (!xen_domain()) > return 0; > > if (!acpi_disabled) > xen_acpi_guest_init(); > - else > + else { > xen_dt_guest_init(); > > + if (!xen_grant_frames) > + return -ENODEV; maybe we can avoid this, see below > + } > + > if (!xen_events_irq) { > pr_err("Xen event channel interrupt not found\n"); > return -ENODEV; > @@ -370,12 +384,16 @@ static int __init xen_guest_init(void) > for_each_possible_cpu(cpu) > per_cpu(xen_vcpu_id, cpu) = cpu; > > - xen_auto_xlat_grant_frames.count = gnttab_max_grant_frames(); > - if (xen_xlate_map_ballooned_pages(&xen_auto_xlat_grant_frames.pfn, > - &xen_auto_xlat_grant_frames.vaddr, > - xen_auto_xlat_grant_frames.count)) { > + if (!acpi_disabled) { To make the code more resilient couldn't we do: if (!acpi_disabled || !xen_grant_frames) { > + xen_auto_xlat_grant_frames.count = gnttab_max_grant_frames(); > + rc = xen_xlate_map_ballooned_pages(&xen_auto_xlat_grant_frames.pfn, > + &xen_auto_xlat_grant_frames.vaddr, > + xen_auto_xlat_grant_frames.count); > + } else > + rc = gnttab_setup_auto_xlat_frames(xen_grant_frames); > + if (rc) { > free_percpu(xen_vcpu_info); > - return -ENOMEM; > + return rc; > } > gnttab_init();
On 28.10.21 04:28, Stefano Stabellini wrote: Hi Stefano I am sorry for the late response. > On Tue, 26 Oct 2021, Oleksandr Tyshchenko wrote: >> From: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> >> >> Read the start address of the grant table space from DT >> (region 0). >> >> This patch mostly restores behaviour before commit 3cf4095d7446 >> ("arm/xen: Use xen_xlate_map_ballooned_pages to setup grant table") >> but trying not to break the ACPI support added after that commit. >> So the patch touches DT part only and leaves the ACPI part with >> xen_xlate_map_ballooned_pages(). >> >> This is a preparation for using Xen extended region feature >> where unused regions of guest physical address space (provided >> by the hypervisor) will be used to create grant/foreign/whatever >> mappings instead of wasting real RAM pages from the domain memory >> for establishing these mappings. >> >> The immediate benefit of this change: >> - Avoid superpage shattering in Xen P2M when establishing >> stage-2 mapping (GFN <-> MFN) for the grant table space >> - Avoid wasting real RAM pages (reducing the amount of memory >> usuable) for mapping grant table space >> - The grant table space is always mapped at the exact >> same place (region 0 is reserved for the grant table) >> >> Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> >> --- >> Changes RFC -> V2: >> - new patch >> --- >> arch/arm/xen/enlighten.c | 32 +++++++++++++++++++++++++------- >> 1 file changed, 25 insertions(+), 7 deletions(-) >> >> diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c >> index 7f1c106b..dea46ec 100644 >> --- a/arch/arm/xen/enlighten.c >> +++ b/arch/arm/xen/enlighten.c >> @@ -59,6 +59,9 @@ unsigned long xen_released_pages; >> struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata; >> >> static __read_mostly unsigned int xen_events_irq; >> +static phys_addr_t xen_grant_frames; > __read_mostly ok > > >> +#define GRANT_TABLE_INDEX 0 >> >> uint32_t xen_start_flags; >> EXPORT_SYMBOL(xen_start_flags); >> @@ -303,6 +306,7 @@ static void __init xen_acpi_guest_init(void) >> static void __init xen_dt_guest_init(void) >> { >> struct device_node *xen_node; >> + struct resource res; >> >> xen_node = of_find_compatible_node(NULL, NULL, "xen,xen"); >> if (!xen_node) { >> @@ -310,6 +314,12 @@ static void __init xen_dt_guest_init(void) >> return; >> } >> >> + if (of_address_to_resource(xen_node, GRANT_TABLE_INDEX, &res)) { >> + pr_err("Xen grant table region is not found\n"); >> + return; >> + } >> + xen_grant_frames = res.start; >> + >> xen_events_irq = irq_of_parse_and_map(xen_node, 0); >> } >> >> @@ -317,16 +327,20 @@ static int __init xen_guest_init(void) >> { >> struct xen_add_to_physmap xatp; >> struct shared_info *shared_info_page = NULL; >> - int cpu; >> + int rc, cpu; >> >> if (!xen_domain()) >> return 0; >> >> if (!acpi_disabled) >> xen_acpi_guest_init(); >> - else >> + else { >> xen_dt_guest_init(); >> >> + if (!xen_grant_frames) >> + return -ENODEV; > maybe we can avoid this, see below > > >> + } >> + >> if (!xen_events_irq) { >> pr_err("Xen event channel interrupt not found\n"); >> return -ENODEV; >> @@ -370,12 +384,16 @@ static int __init xen_guest_init(void) >> for_each_possible_cpu(cpu) >> per_cpu(xen_vcpu_id, cpu) = cpu; >> >> - xen_auto_xlat_grant_frames.count = gnttab_max_grant_frames(); >> - if (xen_xlate_map_ballooned_pages(&xen_auto_xlat_grant_frames.pfn, >> - &xen_auto_xlat_grant_frames.vaddr, >> - xen_auto_xlat_grant_frames.count)) { >> + if (!acpi_disabled) { > To make the code more resilient couldn't we do: > > if (!acpi_disabled || !xen_grant_frames) { I think, we can. On the one hand, indeed the code more resilient and less change. From the other hand if grant table region is not found then something weird happened as region 0 is always present in reg property if hypervisor node is exposed to the guest. The behavior before commit 3cf4095d7446 ("arm/xen: Use xen_xlate_map_ballooned_pages to setup grant table") was exactly the same in the context of the failure if region wasn't found. ... Well, if we want to make code more resilient, I will update. But, looks like we also need to switch actions in xen_dt_guest_init() in order to process xen_events_irq before xen_grant_frames, otherwise we may return after failing with region and end up not initializing xen_events_irq so xen_guest_init() will fail earlier than reaches that check. What do you think? > >> + xen_auto_xlat_grant_frames.count = gnttab_max_grant_frames(); >> + rc = xen_xlate_map_ballooned_pages(&xen_auto_xlat_grant_frames.pfn, >> + &xen_auto_xlat_grant_frames.vaddr, >> + xen_auto_xlat_grant_frames.count); >> + } else >> + rc = gnttab_setup_auto_xlat_frames(xen_grant_frames); >> + if (rc) { >> free_percpu(xen_vcpu_info); >> - return -ENOMEM; >> + return rc; >> } >> gnttab_init();
On Thu, 11 Nov 2021, Oleksandr wrote: > On 28.10.21 04:28, Stefano Stabellini wrote: > > Hi Stefano > > I am sorry for the late response. > > > On Tue, 26 Oct 2021, Oleksandr Tyshchenko wrote: > > > From: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> > > > > > > Read the start address of the grant table space from DT > > > (region 0). > > > > > > This patch mostly restores behaviour before commit 3cf4095d7446 > > > ("arm/xen: Use xen_xlate_map_ballooned_pages to setup grant table") > > > but trying not to break the ACPI support added after that commit. > > > So the patch touches DT part only and leaves the ACPI part with > > > xen_xlate_map_ballooned_pages(). > > > > > > This is a preparation for using Xen extended region feature > > > where unused regions of guest physical address space (provided > > > by the hypervisor) will be used to create grant/foreign/whatever > > > mappings instead of wasting real RAM pages from the domain memory > > > for establishing these mappings. > > > > > > The immediate benefit of this change: > > > - Avoid superpage shattering in Xen P2M when establishing > > > stage-2 mapping (GFN <-> MFN) for the grant table space > > > - Avoid wasting real RAM pages (reducing the amount of memory > > > usuable) for mapping grant table space > > > - The grant table space is always mapped at the exact > > > same place (region 0 is reserved for the grant table) > > > > > > Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> > > > --- > > > Changes RFC -> V2: > > > - new patch > > > --- > > > arch/arm/xen/enlighten.c | 32 +++++++++++++++++++++++++------- > > > 1 file changed, 25 insertions(+), 7 deletions(-) > > > > > > diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c > > > index 7f1c106b..dea46ec 100644 > > > --- a/arch/arm/xen/enlighten.c > > > +++ b/arch/arm/xen/enlighten.c > > > @@ -59,6 +59,9 @@ unsigned long xen_released_pages; > > > struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] > > > __initdata; > > > static __read_mostly unsigned int xen_events_irq; > > > +static phys_addr_t xen_grant_frames; > > __read_mostly > > ok > > > > > > > > > +#define GRANT_TABLE_INDEX 0 > > > uint32_t xen_start_flags; > > > EXPORT_SYMBOL(xen_start_flags); > > > @@ -303,6 +306,7 @@ static void __init xen_acpi_guest_init(void) > > > static void __init xen_dt_guest_init(void) > > > { > > > struct device_node *xen_node; > > > + struct resource res; > > > xen_node = of_find_compatible_node(NULL, NULL, "xen,xen"); > > > if (!xen_node) { > > > @@ -310,6 +314,12 @@ static void __init xen_dt_guest_init(void) > > > return; > > > } > > > + if (of_address_to_resource(xen_node, GRANT_TABLE_INDEX, &res)) { > > > + pr_err("Xen grant table region is not found\n"); > > > + return; > > > + } > > > + xen_grant_frames = res.start; > > > + > > > xen_events_irq = irq_of_parse_and_map(xen_node, 0); > > > } > > > @@ -317,16 +327,20 @@ static int __init xen_guest_init(void) > > > { > > > struct xen_add_to_physmap xatp; > > > struct shared_info *shared_info_page = NULL; > > > - int cpu; > > > + int rc, cpu; > > > if (!xen_domain()) > > > return 0; > > > if (!acpi_disabled) > > > xen_acpi_guest_init(); > > > - else > > > + else { > > > xen_dt_guest_init(); > > > + if (!xen_grant_frames) > > > + return -ENODEV; > > maybe we can avoid this, see below > > > > > > > + } > > > + > > > if (!xen_events_irq) { > > > pr_err("Xen event channel interrupt not found\n"); > > > return -ENODEV; > > > @@ -370,12 +384,16 @@ static int __init xen_guest_init(void) > > > for_each_possible_cpu(cpu) > > > per_cpu(xen_vcpu_id, cpu) = cpu; > > > - xen_auto_xlat_grant_frames.count = gnttab_max_grant_frames(); > > > - if (xen_xlate_map_ballooned_pages(&xen_auto_xlat_grant_frames.pfn, > > > - &xen_auto_xlat_grant_frames.vaddr, > > > - xen_auto_xlat_grant_frames.count)) { > > > + if (!acpi_disabled) { > > To make the code more resilient couldn't we do: > > > > if (!acpi_disabled || !xen_grant_frames) { > I think, we can. > > On the one hand, indeed the code more resilient and less change. > From the other hand if grant table region is not found then something weird > happened as region 0 is always present in reg property if hypervisor node is > exposed to the guest. > The behavior before commit 3cf4095d7446 ("arm/xen: Use > xen_xlate_map_ballooned_pages to setup grant table") was exactly the same in > the context of the failure if region wasn't found. > > ... > > Well, if we want to make code more resilient, I will update. But, looks like > we also need to switch actions in xen_dt_guest_init() in order to process > xen_events_irq before xen_grant_frames, otherwise we may return after failing > with region and end up not initializing xen_events_irq so xen_guest_init() > will fail earlier than reaches that check. > What do you think? Yes, you are right. I was re-reading the patch to refresh my memory and I noticed immediately that xen_dt_guest_init also need to be changed so that xen_events_irq is set before xen_grant_frames. I think it is a minor change that doesn't add complexity but make the code more robust so I think it is a good idea > > > + xen_auto_xlat_grant_frames.count = gnttab_max_grant_frames(); > > > + rc = > > > xen_xlate_map_ballooned_pages(&xen_auto_xlat_grant_frames.pfn, > > > + > > > &xen_auto_xlat_grant_frames.vaddr, > > > + > > > xen_auto_xlat_grant_frames.count); > > > + } else > > > + rc = gnttab_setup_auto_xlat_frames(xen_grant_frames); > > > + if (rc) { > > > free_percpu(xen_vcpu_info); > > > - return -ENOMEM; > > > + return rc; > > > } > > > gnttab_init();
On 19.11.21 02:32, Stefano Stabellini wrote: Hi Stefano > On Thu, 11 Nov 2021, Oleksandr wrote: >> On 28.10.21 04:28, Stefano Stabellini wrote: >> >> Hi Stefano >> >> I am sorry for the late response. >> >>> On Tue, 26 Oct 2021, Oleksandr Tyshchenko wrote: >>>> From: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> >>>> >>>> Read the start address of the grant table space from DT >>>> (region 0). >>>> >>>> This patch mostly restores behaviour before commit 3cf4095d7446 >>>> ("arm/xen: Use xen_xlate_map_ballooned_pages to setup grant table") >>>> but trying not to break the ACPI support added after that commit. >>>> So the patch touches DT part only and leaves the ACPI part with >>>> xen_xlate_map_ballooned_pages(). >>>> >>>> This is a preparation for using Xen extended region feature >>>> where unused regions of guest physical address space (provided >>>> by the hypervisor) will be used to create grant/foreign/whatever >>>> mappings instead of wasting real RAM pages from the domain memory >>>> for establishing these mappings. >>>> >>>> The immediate benefit of this change: >>>> - Avoid superpage shattering in Xen P2M when establishing >>>> stage-2 mapping (GFN <-> MFN) for the grant table space >>>> - Avoid wasting real RAM pages (reducing the amount of memory >>>> usuable) for mapping grant table space >>>> - The grant table space is always mapped at the exact >>>> same place (region 0 is reserved for the grant table) >>>> >>>> Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> >>>> --- >>>> Changes RFC -> V2: >>>> - new patch >>>> --- >>>> arch/arm/xen/enlighten.c | 32 +++++++++++++++++++++++++------- >>>> 1 file changed, 25 insertions(+), 7 deletions(-) >>>> >>>> diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c >>>> index 7f1c106b..dea46ec 100644 >>>> --- a/arch/arm/xen/enlighten.c >>>> +++ b/arch/arm/xen/enlighten.c >>>> @@ -59,6 +59,9 @@ unsigned long xen_released_pages; >>>> struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] >>>> __initdata; >>>> static __read_mostly unsigned int xen_events_irq; >>>> +static phys_addr_t xen_grant_frames; >>> __read_mostly >> ok >> >> >>> >>>> +#define GRANT_TABLE_INDEX 0 >>>> uint32_t xen_start_flags; >>>> EXPORT_SYMBOL(xen_start_flags); >>>> @@ -303,6 +306,7 @@ static void __init xen_acpi_guest_init(void) >>>> static void __init xen_dt_guest_init(void) >>>> { >>>> struct device_node *xen_node; >>>> + struct resource res; >>>> xen_node = of_find_compatible_node(NULL, NULL, "xen,xen"); >>>> if (!xen_node) { >>>> @@ -310,6 +314,12 @@ static void __init xen_dt_guest_init(void) >>>> return; >>>> } >>>> + if (of_address_to_resource(xen_node, GRANT_TABLE_INDEX, &res)) { >>>> + pr_err("Xen grant table region is not found\n"); >>>> + return; >>>> + } >>>> + xen_grant_frames = res.start; >>>> + >>>> xen_events_irq = irq_of_parse_and_map(xen_node, 0); >>>> } >>>> @@ -317,16 +327,20 @@ static int __init xen_guest_init(void) >>>> { >>>> struct xen_add_to_physmap xatp; >>>> struct shared_info *shared_info_page = NULL; >>>> - int cpu; >>>> + int rc, cpu; >>>> if (!xen_domain()) >>>> return 0; >>>> if (!acpi_disabled) >>>> xen_acpi_guest_init(); >>>> - else >>>> + else { >>>> xen_dt_guest_init(); >>>> + if (!xen_grant_frames) >>>> + return -ENODEV; >>> maybe we can avoid this, see below >>> >>> >>>> + } >>>> + >>>> if (!xen_events_irq) { >>>> pr_err("Xen event channel interrupt not found\n"); >>>> return -ENODEV; >>>> @@ -370,12 +384,16 @@ static int __init xen_guest_init(void) >>>> for_each_possible_cpu(cpu) >>>> per_cpu(xen_vcpu_id, cpu) = cpu; >>>> - xen_auto_xlat_grant_frames.count = gnttab_max_grant_frames(); >>>> - if (xen_xlate_map_ballooned_pages(&xen_auto_xlat_grant_frames.pfn, >>>> - &xen_auto_xlat_grant_frames.vaddr, >>>> - xen_auto_xlat_grant_frames.count)) { >>>> + if (!acpi_disabled) { >>> To make the code more resilient couldn't we do: >>> >>> if (!acpi_disabled || !xen_grant_frames) { >> I think, we can. >> >> On the one hand, indeed the code more resilient and less change. >> From the other hand if grant table region is not found then something weird >> happened as region 0 is always present in reg property if hypervisor node is >> exposed to the guest. >> The behavior before commit 3cf4095d7446 ("arm/xen: Use >> xen_xlate_map_ballooned_pages to setup grant table") was exactly the same in >> the context of the failure if region wasn't found. >> >> ... >> >> Well, if we want to make code more resilient, I will update. But, looks like >> we also need to switch actions in xen_dt_guest_init() in order to process >> xen_events_irq before xen_grant_frames, otherwise we may return after failing >> with region and end up not initializing xen_events_irq so xen_guest_init() >> will fail earlier than reaches that check. >> What do you think? > > Yes, you are right. I was re-reading the patch to refresh my memory and > I noticed immediately that xen_dt_guest_init also need to be changed so > that xen_events_irq is set before xen_grant_frames. > > I think it is a minor change that doesn't add complexity but make the > code more robust so I think it is a good idea Great, thank you. Will do in next version. > > >>>> + xen_auto_xlat_grant_frames.count = gnttab_max_grant_frames(); >>>> + rc = >>>> xen_xlate_map_ballooned_pages(&xen_auto_xlat_grant_frames.pfn, >>>> + >>>> &xen_auto_xlat_grant_frames.vaddr, >>>> + >>>> xen_auto_xlat_grant_frames.count); >>>> + } else >>>> + rc = gnttab_setup_auto_xlat_frames(xen_grant_frames); >>>> + if (rc) { >>>> free_percpu(xen_vcpu_info); >>>> - return -ENOMEM; >>>> + return rc; >>>> } >>>> gnttab_init();
diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c index 7f1c106b..dea46ec 100644 --- a/arch/arm/xen/enlighten.c +++ b/arch/arm/xen/enlighten.c @@ -59,6 +59,9 @@ unsigned long xen_released_pages; struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata; static __read_mostly unsigned int xen_events_irq; +static phys_addr_t xen_grant_frames; + +#define GRANT_TABLE_INDEX 0 uint32_t xen_start_flags; EXPORT_SYMBOL(xen_start_flags); @@ -303,6 +306,7 @@ static void __init xen_acpi_guest_init(void) static void __init xen_dt_guest_init(void) { struct device_node *xen_node; + struct resource res; xen_node = of_find_compatible_node(NULL, NULL, "xen,xen"); if (!xen_node) { @@ -310,6 +314,12 @@ static void __init xen_dt_guest_init(void) return; } + if (of_address_to_resource(xen_node, GRANT_TABLE_INDEX, &res)) { + pr_err("Xen grant table region is not found\n"); + return; + } + xen_grant_frames = res.start; + xen_events_irq = irq_of_parse_and_map(xen_node, 0); } @@ -317,16 +327,20 @@ static int __init xen_guest_init(void) { struct xen_add_to_physmap xatp; struct shared_info *shared_info_page = NULL; - int cpu; + int rc, cpu; if (!xen_domain()) return 0; if (!acpi_disabled) xen_acpi_guest_init(); - else + else { xen_dt_guest_init(); + if (!xen_grant_frames) + return -ENODEV; + } + if (!xen_events_irq) { pr_err("Xen event channel interrupt not found\n"); return -ENODEV; @@ -370,12 +384,16 @@ static int __init xen_guest_init(void) for_each_possible_cpu(cpu) per_cpu(xen_vcpu_id, cpu) = cpu; - xen_auto_xlat_grant_frames.count = gnttab_max_grant_frames(); - if (xen_xlate_map_ballooned_pages(&xen_auto_xlat_grant_frames.pfn, - &xen_auto_xlat_grant_frames.vaddr, - xen_auto_xlat_grant_frames.count)) { + if (!acpi_disabled) { + xen_auto_xlat_grant_frames.count = gnttab_max_grant_frames(); + rc = xen_xlate_map_ballooned_pages(&xen_auto_xlat_grant_frames.pfn, + &xen_auto_xlat_grant_frames.vaddr, + xen_auto_xlat_grant_frames.count); + } else + rc = gnttab_setup_auto_xlat_frames(xen_grant_frames); + if (rc) { free_percpu(xen_vcpu_info); - return -ENOMEM; + return rc; } gnttab_init();