* [PATCH V3 0/3] x86/Hyper-V/IOMMU: Add Hyper-V IOMMU driver to support x2apic mode @ 2019-02-07 15:33 lantianyu1986 [not found] ` <1549553629-8414-1-git-send-email-Tianyu.Lan-0li6OtcxBFHby3iVrkZq2A@public.gmane.org> 2019-02-07 15:33 ` [PATCH V3 2/3] HYPERV/IOMMU: Add Hyper-V stub IOMMU driver lantianyu1986 0 siblings, 2 replies; 11+ messages in thread From: lantianyu1986 @ 2019-02-07 15:33 UTC (permalink / raw) Cc: Lan Tianyu, arnd, bp, davem, devel, gregkh, haiyangz, hpa, iommu, joro, kys, linux-kernel, mchehab+samsung, mingo, nicolas.ferre, sashal, sthemmin, tglx, x86, michael.h.kelley, vkuznets, alex.williamson, dan.carpenter From: Lan Tianyu <Tianyu.Lan@microsoft.com> On the bare metal, enabling X2APIC mode requires interrupt remapping function which helps to deliver irq to cpu with 32-bit APIC ID. Hyper-V doesn't provide interrupt remapping function so far and Hyper-V MSI protocol already supports to deliver interrupt to the CPU whose virtual processor index is more than 255. IO-APIC interrupt still has 8-bit APIC ID limitation. This patchset is to add Hyper-V stub IOMMU driver in order to enable X2APIC mode successfully in Hyper-V Linux guest. The driver returns X2APIC interrupt remapping capability when X2APIC mode is available. X2APIC destination mode is set to physical by PATCH 1 when X2APIC is available. Hyper-V IOMMU driver will scan cpu 0~255 and set cpu into IO-APIC MAX cpu affinity cpumask if its APIC ID is 8-bit. Driver creates a Hyper-V irq domain to limit IO-APIC interrupts' affinity and make sure cpus assigned with IO-APIC interrupt are in the scope of IO-APIC MAX cpu affinity. Lan Tianyu (3): x86/Hyper-V: Set x2apic destination mode to physical when x2apic is available HYPERV/IOMMU: Add Hyper-V stub IOMMU driver MAINTAINERS: Add Hyper-V IOMMU driver into Hyper-V CORE AND DRIVERS scope MAINTAINERS | 1 + arch/x86/kernel/cpu/mshyperv.c | 10 +++ drivers/iommu/Kconfig | 8 ++ drivers/iommu/Makefile | 1 + drivers/iommu/hyperv-iommu.c | 194 +++++++++++++++++++++++++++++++++++++++++ drivers/iommu/irq_remapping.c | 3 + drivers/iommu/irq_remapping.h | 1 + 7 files changed, 218 insertions(+) create mode 100644 drivers/iommu/hyperv-iommu.c -- 2.7.4 ^ permalink raw reply [flat|nested] 11+ messages in thread
[parent not found: <1549553629-8414-1-git-send-email-Tianyu.Lan-0li6OtcxBFHby3iVrkZq2A@public.gmane.org>]
* [PATCH V3 1/3] x86/Hyper-V: Set x2apic destination mode to physical when x2apic is available [not found] ` <1549553629-8414-1-git-send-email-Tianyu.Lan-0li6OtcxBFHby3iVrkZq2A@public.gmane.org> @ 2019-02-07 15:33 ` lantianyu1986-Re5JQEeQqe8AvxtiuMwx3w 2019-02-10 21:48 ` Thomas Gleixner 0 siblings, 1 reply; 11+ messages in thread From: lantianyu1986-Re5JQEeQqe8AvxtiuMwx3w @ 2019-02-07 15:33 UTC (permalink / raw) Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA, hpa-YMNOUZJC4hwAvxtiuMwx3w, mchehab+samsung-DgEjT+Ai2ygdnm+yROfE0A, kys-0li6OtcxBFHby3iVrkZq2A, sashal-DgEjT+Ai2ygdnm+yROfE0A, sthemmin-0li6OtcxBFHby3iVrkZq2A, x86-DgEjT+Ai2ygdnm+yROfE0A, michael.h.kelley-0li6OtcxBFHby3iVrkZq2A, mingo-H+wXaHxf7aLQT0dZR+AlfA, dan.carpenter-QHcLZuEGTsvQT0dZR+AlfA, Lan Tianyu, arnd-r2nGTMty4D4, haiyangz-0li6OtcxBFHby3iVrkZq2A, alex.williamson-H+wXaHxf7aLQT0dZR+AlfA, bp-Gina5bIWoIWzQB+pC5nmwQ, tglx-hfZtesqFncYOwBW4kG4KsQ, gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r, nicolas.ferre-UWL1GkI3JZL3oGB3hsPCZA, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA, devel-tBiZLqfeLfOHmIFyCCdPziST3g8Odh+X, vkuznets-H+wXaHxf7aLQT0dZR+AlfA, davem-fT/PcQaiUtIeIZ0/mPfg9Q From: Lan Tianyu <Tianyu.Lan-0li6OtcxBFHby3iVrkZq2A@public.gmane.org> Hyper-V doesn't provide irq remapping for IO-APIC. To enable x2apic, set x2apic destination mode to physcial mode when x2apic is available and Hyper-V IOMMU driver makes sure cpus assigned with IO-APIC irqs have 8-bit APIC id. Signed-off-by: Lan Tianyu <Tianyu.Lan-0li6OtcxBFHby3iVrkZq2A@public.gmane.org> --- Change since v2: - Fix compile error due to x2apic_phys - Fix comment indent Change since v1: - Remove redundant extern for x2apic_phys --- arch/x86/kernel/cpu/mshyperv.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c index e81a2db..0c29e4e 100644 --- a/arch/x86/kernel/cpu/mshyperv.c +++ b/arch/x86/kernel/cpu/mshyperv.c @@ -328,6 +328,16 @@ static void __init ms_hyperv_init_platform(void) # ifdef CONFIG_SMP smp_ops.smp_prepare_boot_cpu = hv_smp_prepare_boot_cpu; # endif + + /* + * Hyper-V doesn't provide irq remapping for IO-APIC. To enable x2apic, + * set x2apic destination mode to physcial mode when x2apic is available + * and Hyper-V IOMMU driver makes sure cpus assigned with IO-APIC irqs + * have 8-bit APIC id. + */ + if (IS_ENABLED(CONFIG_X86_X2APIC) && x2apic_supported()) + x2apic_phys = 1; + #endif } -- 2.7.4 ^ permalink raw reply related [flat|nested] 11+ messages in thread
* Re: [PATCH V3 1/3] x86/Hyper-V: Set x2apic destination mode to physical when x2apic is available 2019-02-07 15:33 ` [PATCH V3 1/3] x86/Hyper-V: Set x2apic destination mode to physical when x2apic is available lantianyu1986-Re5JQEeQqe8AvxtiuMwx3w @ 2019-02-10 21:48 ` Thomas Gleixner 2019-02-11 8:05 ` Tianyu Lan 0 siblings, 1 reply; 11+ messages in thread From: Thomas Gleixner @ 2019-02-10 21:48 UTC (permalink / raw) To: lantianyu1986 Cc: Lan Tianyu, kys, haiyangz, sthemmin, sashal, mingo, bp, hpa, x86, joro, mchehab+samsung, davem, gregkh, nicolas.ferre, arnd, linux-kernel, devel, iommu, michael.h.kelley, vkuznets, alex.williamson, dan.carpenter On Thu, 7 Feb 2019, lantianyu1986@gmail.com wrote: > From: Lan Tianyu <Tianyu.Lan@microsoft.com> > > Hyper-V doesn't provide irq remapping for IO-APIC. To enable x2apic, > set x2apic destination mode to physcial mode when x2apic is available > and Hyper-V IOMMU driver makes sure cpus assigned with IO-APIC irqs have > 8-bit APIC id. This looks good now. Can that be applied independent of the IOMMU stuff or should this go together. If the latter: Reviewed-by: Thomas Gleixner <tglx@linutronix.de> If not, I just queue if for 5.1. Let me know, Thanks, tglx ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH V3 1/3] x86/Hyper-V: Set x2apic destination mode to physical when x2apic is available 2019-02-10 21:48 ` Thomas Gleixner @ 2019-02-11 8:05 ` Tianyu Lan 0 siblings, 0 replies; 11+ messages in thread From: Tianyu Lan @ 2019-02-11 8:05 UTC (permalink / raw) To: Thomas Gleixner Cc: linux-kernel@vger kernel org, H. Peter Anvin, mchehab+samsung, Sasha Levin, sthemmin, Joerg Roedel, the arch/x86 maintainers, michael.h.kelley, Ingo Molnar, Dan Carpenter, Lan Tianyu, Arnd Bergmann, haiyangz, Alex Williamson, bp, Greg Kroah-Hartman, nicolas.ferre, iommu, devel, Vitaly Kuznetsov, davem Hi Thomas: Thanks for your review. On Mon, Feb 11, 2019 at 5:48 AM Thomas Gleixner <tglx@linutronix.de> wrote: > > On Thu, 7 Feb 2019, lantianyu1986@gmail.com wrote: > > > From: Lan Tianyu <Tianyu.Lan@microsoft.com> > > > > Hyper-V doesn't provide irq remapping for IO-APIC. To enable x2apic, > > set x2apic destination mode to physcial mode when x2apic is available > > and Hyper-V IOMMU driver makes sure cpus assigned with IO-APIC irqs have > > 8-bit APIC id. > > This looks good now. Can that be applied independent of the IOMMU stuff or > should this go together. If the latter: > > Reviewed-by: Thomas Gleixner <tglx@linutronix.de> > > If not, I just queue if for 5.1. Let me know, > This patch can be applied independently. Thanks. -- Best regards Tianyu Lan ^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH V3 2/3] HYPERV/IOMMU: Add Hyper-V stub IOMMU driver 2019-02-07 15:33 [PATCH V3 0/3] x86/Hyper-V/IOMMU: Add Hyper-V IOMMU driver to support x2apic mode lantianyu1986 [not found] ` <1549553629-8414-1-git-send-email-Tianyu.Lan-0li6OtcxBFHby3iVrkZq2A@public.gmane.org> @ 2019-02-07 15:33 ` lantianyu1986 2019-02-07 17:15 ` Vitaly Kuznetsov ` (2 more replies) 1 sibling, 3 replies; 11+ messages in thread From: lantianyu1986 @ 2019-02-07 15:33 UTC (permalink / raw) Cc: Lan Tianyu, joro, mchehab+samsung, davem, gregkh, nicolas.ferre, arnd, linux-kernel, iommu, michael.h.kelley, kys, vkuznets, alex.williamson, sashal, dan.carpenter From: Lan Tianyu <Tianyu.Lan@microsoft.com> On the bare metal, enabling X2APIC mode requires interrupt remapping function which helps to deliver irq to cpu with 32-bit APIC ID. Hyper-V doesn't provide interrupt remapping function so far and Hyper-V MSI protocol already supports to deliver interrupt to the CPU whose virtual processor index is more than 255. IO-APIC interrupt still has 8-bit APIC ID limitation. This patch is to add Hyper-V stub IOMMU driver in order to enable X2APIC mode successfully in Hyper-V Linux guest. The driver returns X2APIC interrupt remapping capability when X2APIC mode is available. Otherwise, it creates a Hyper-V irq domain to limit IO-APIC interrupts' affinity and make sure cpus assigned with IO-APIC interrupt have 8-bit APIC ID. Define 24 IO-APIC remapping entries because Hyper-V only expose one single IO-APIC and one IO-APIC has 24 pins according IO-APIC spec( https://pdos.csail.mit.edu/6.828/2016/readings/ia32/ioapic.pdf). Signed-off-by: Lan Tianyu <Tianyu.Lan@microsoft.com> --- Change since v2: - Improve comment about why save IO-APIC entry in the irq chip data. - Some code improvement. - Improve statement in the IOMMU Kconfig. Change since v1: - Remove unused pr_fmt - Make ioapic_ir_domain as static variable - Remove unused variables cfg and entry in the hyperv_irq_remapping_alloc() - Fix comments --- drivers/iommu/Kconfig | 8 ++ drivers/iommu/Makefile | 1 + drivers/iommu/hyperv-iommu.c | 194 ++++++++++++++++++++++++++++++++++++++++++ drivers/iommu/irq_remapping.c | 3 + drivers/iommu/irq_remapping.h | 1 + 5 files changed, 207 insertions(+) create mode 100644 drivers/iommu/hyperv-iommu.c diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig index 45d7021..6090935 100644 --- a/drivers/iommu/Kconfig +++ b/drivers/iommu/Kconfig @@ -437,4 +437,12 @@ config QCOM_IOMMU help Support for IOMMU on certain Qualcomm SoCs. +config HYPERV_IOMMU + bool "Hyper-V x2APIC IRQ Handling" + depends on HYPERV + select IOMMU_API + help + Stub IOMMU driver to handle IRQs as to allow Hyper-V Linux + guests to run with x2APIC mode enabled. + endif # IOMMU_SUPPORT diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile index a158a68..8c71a15 100644 --- a/drivers/iommu/Makefile +++ b/drivers/iommu/Makefile @@ -32,3 +32,4 @@ obj-$(CONFIG_EXYNOS_IOMMU) += exynos-iommu.o obj-$(CONFIG_FSL_PAMU) += fsl_pamu.o fsl_pamu_domain.o obj-$(CONFIG_S390_IOMMU) += s390-iommu.o obj-$(CONFIG_QCOM_IOMMU) += qcom_iommu.o +obj-$(CONFIG_HYPERV_IOMMU) += hyperv-iommu.o diff --git a/drivers/iommu/hyperv-iommu.c b/drivers/iommu/hyperv-iommu.c new file mode 100644 index 0000000..d8572c5 --- /dev/null +++ b/drivers/iommu/hyperv-iommu.c @@ -0,0 +1,194 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * Hyper-V stub IOMMU driver. + * + * Copyright (C) 2019, Microsoft, Inc. + * + * Author : Lan Tianyu <Tianyu.Lan@microsoft.com> + */ + +#include <linux/types.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/iommu.h> +#include <linux/module.h> + +#include <asm/hw_irq.h> +#include <asm/io_apic.h> +#include <asm/irq_remapping.h> +#include <asm/hypervisor.h> + +#include "irq_remapping.h" + +#ifdef CONFIG_IRQ_REMAP + +/* + * According 82093AA IO-APIC spec , IO APIC has a 24-entry Interrupt + * Redirection Table. Hyper-V exposes one single IO-APIC and so define + * 24 IO APIC remmapping entries. + */ +#define IOAPIC_REMAPPING_ENTRY 24 + +static cpumask_t ioapic_max_cpumask = { CPU_BITS_NONE }; +static struct irq_domain *ioapic_ir_domain; + +static int hyperv_ir_set_affinity(struct irq_data *data, + const struct cpumask *mask, bool force) +{ + struct irq_data *parent = data->parent_data; + struct irq_cfg *cfg = irqd_cfg(data); + struct IO_APIC_route_entry *entry; + int ret; + + /* Return error If new irq affinity is out of ioapic_max_cpumask. */ + if (!cpumask_subset(mask, &ioapic_max_cpumask)) + return -EINVAL; + + ret = parent->chip->irq_set_affinity(parent, mask, force); + if (ret < 0 || ret == IRQ_SET_MASK_OK_DONE) + return ret; + + entry = data->chip_data; + entry->dest = cfg->dest_apicid; + entry->vector = cfg->vector; + send_cleanup_vector(cfg); + + return 0; +} + +static struct irq_chip hyperv_ir_chip = { + .name = "HYPERV-IR", + .irq_ack = apic_ack_irq, + .irq_set_affinity = hyperv_ir_set_affinity, +}; + +static int hyperv_irq_remapping_alloc(struct irq_domain *domain, + unsigned int virq, unsigned int nr_irqs, + void *arg) +{ + struct irq_alloc_info *info = arg; + struct irq_data *irq_data; + struct irq_desc *desc; + int ret = 0; + + if (!info || info->type != X86_IRQ_ALLOC_TYPE_IOAPIC || nr_irqs > 1) + return -EINVAL; + + ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, arg); + if (ret < 0) + return ret; + + irq_data = irq_domain_get_irq_data(domain, virq); + if (!irq_data) { + irq_domain_free_irqs_common(domain, virq, nr_irqs); + return -EINVAL; + } + + irq_data->chip = &hyperv_ir_chip; + + /* + * If there is interrupt remapping function of IOMMU, setting irq + * affinity only needs to change IRTE of IOMMU. But Hyper-V doesn't + * support interrupt remapping function, setting irq affinity of IO-APIC + * interrupts still needs to change IO-APIC registers. But ioapic_ + * configure_entry() will ignore value of cfg->vector and cfg-> + * dest_apicid when IO-APIC's parent irq domain is not the vector + * domain.(See ioapic_configure_entry()) In order to setting vector + * and dest_apicid to IO-APIC register, IO-APIC entry pointer is saved + * in the chip_data and hyperv_irq_remapping_activate()/hyperv_ir_set_ + * affinity() set vector and dest_apicid directly into IO-APIC entry. + */ + irq_data->chip_data = info->ioapic_entry; + + /* + * Hypver-V IO APIC irq affinity should be in the scope of + * ioapic_max_cpumask because no irq remapping support. + */ + desc = irq_data_to_desc(irq_data); + cpumask_copy(desc->irq_common_data.affinity, &ioapic_max_cpumask); + + return 0; +} + +static void hyperv_irq_remapping_free(struct irq_domain *domain, + unsigned int virq, unsigned int nr_irqs) +{ + irq_domain_free_irqs_common(domain, virq, nr_irqs); +} + +static int hyperv_irq_remapping_activate(struct irq_domain *domain, + struct irq_data *irq_data, bool reserve) +{ + struct irq_cfg *cfg = irqd_cfg(irq_data); + struct IO_APIC_route_entry *entry = irq_data->chip_data; + + entry->dest = cfg->dest_apicid; + entry->vector = cfg->vector; + + return 0; +} + +static struct irq_domain_ops hyperv_ir_domain_ops = { + .alloc = hyperv_irq_remapping_alloc, + .free = hyperv_irq_remapping_free, + .activate = hyperv_irq_remapping_activate, +}; + +static int __init hyperv_prepare_irq_remapping(void) +{ + struct fwnode_handle *fn; + int i; + + if (!hypervisor_is_type(x86_hyper_type) || + !x2apic_supported()) + return -ENODEV; + + fn = irq_domain_alloc_named_id_fwnode("HYPERV-IR", 0); + if (!fn) + return -ENOMEM; + + ioapic_ir_domain = + irq_domain_create_hierarchy(arch_get_ir_parent_domain(), + 0, IOAPIC_REMAPPING_ENTRY, fn, + &hyperv_ir_domain_ops, NULL); + + irq_domain_free_fwnode(fn); + + /* + * Hyper-V doesn't provide irq remapping function for + * IO-APIC and so IO-APIC only accepts 8-bit APIC ID. + * Cpu's APIC ID is read from ACPI MADT table and APIC IDs + * in the MADT table on Hyper-v are sorted monotonic increasingly. + * APIC ID reflects cpu topology. There maybe some APIC ID + * gaps when cpu number in a socket is not power of two. Prepare + * max cpu affinity for IOAPIC irqs. Scan cpu 0-255 and set cpu + * into ioapic_max_cpumask if its APIC ID is less than 256. + */ + for (i = 0; i < 256; i++) + if (cpu_physical_id(i) < 256) + cpumask_set_cpu(i, &ioapic_max_cpumask); + + return 0; +} + +static int __init hyperv_enable_irq_remapping(void) +{ + return IRQ_REMAP_X2APIC_MODE; +} + +static struct irq_domain *hyperv_get_ir_irq_domain(struct irq_alloc_info *info) +{ + if (info->type == X86_IRQ_ALLOC_TYPE_IOAPIC) + return ioapic_ir_domain; + else + return NULL; +} + +struct irq_remap_ops hyperv_irq_remap_ops = { + .prepare = hyperv_prepare_irq_remapping, + .enable = hyperv_enable_irq_remapping, + .get_ir_irq_domain = hyperv_get_ir_irq_domain, +}; + +#endif diff --git a/drivers/iommu/irq_remapping.c b/drivers/iommu/irq_remapping.c index b94ebd4..81cf290 100644 --- a/drivers/iommu/irq_remapping.c +++ b/drivers/iommu/irq_remapping.c @@ -103,6 +103,9 @@ int __init irq_remapping_prepare(void) else if (IS_ENABLED(CONFIG_AMD_IOMMU) && amd_iommu_irq_ops.prepare() == 0) remap_ops = &amd_iommu_irq_ops; + else if (IS_ENABLED(CONFIG_HYPERV_IOMMU) && + hyperv_irq_remap_ops.prepare() == 0) + remap_ops = &hyperv_irq_remap_ops; else return -ENOSYS; diff --git a/drivers/iommu/irq_remapping.h b/drivers/iommu/irq_remapping.h index 0afef6e..f8609e9 100644 --- a/drivers/iommu/irq_remapping.h +++ b/drivers/iommu/irq_remapping.h @@ -64,6 +64,7 @@ struct irq_remap_ops { extern struct irq_remap_ops intel_irq_remap_ops; extern struct irq_remap_ops amd_iommu_irq_ops; +extern struct irq_remap_ops hyperv_irq_remap_ops; #else /* CONFIG_IRQ_REMAP */ -- 2.7.4 ^ permalink raw reply related [flat|nested] 11+ messages in thread
* Re: [PATCH V3 2/3] HYPERV/IOMMU: Add Hyper-V stub IOMMU driver 2019-02-07 15:33 ` [PATCH V3 2/3] HYPERV/IOMMU: Add Hyper-V stub IOMMU driver lantianyu1986 @ 2019-02-07 17:15 ` Vitaly Kuznetsov 2019-02-11 8:19 ` Tianyu Lan [not found] ` <1549553629-8414-3-git-send-email-Tianyu.Lan-0li6OtcxBFHby3iVrkZq2A@public.gmane.org> 2019-02-08 14:51 ` Olaf Hering 2 siblings, 1 reply; 11+ messages in thread From: Vitaly Kuznetsov @ 2019-02-07 17:15 UTC (permalink / raw) To: lantianyu1986 Cc: Lan Tianyu, joro, mchehab+samsung, davem, gregkh, nicolas.ferre, arnd, linux-kernel, iommu, michael.h.kelley, kys, alex.williamson, sashal, dan.carpenter lantianyu1986@gmail.com writes: > From: Lan Tianyu <Tianyu.Lan@microsoft.com> > > On the bare metal, enabling X2APIC mode requires interrupt remapping > function which helps to deliver irq to cpu with 32-bit APIC ID. > Hyper-V doesn't provide interrupt remapping function so far and Hyper-V > MSI protocol already supports to deliver interrupt to the CPU whose > virtual processor index is more than 255. IO-APIC interrupt still has > 8-bit APIC ID limitation. > > This patch is to add Hyper-V stub IOMMU driver in order to enable > X2APIC mode successfully in Hyper-V Linux guest. The driver returns X2APIC > interrupt remapping capability when X2APIC mode is available. Otherwise, > it creates a Hyper-V irq domain to limit IO-APIC interrupts' affinity > and make sure cpus assigned with IO-APIC interrupt have 8-bit APIC ID. > > Define 24 IO-APIC remapping entries because Hyper-V only expose one > single IO-APIC and one IO-APIC has 24 pins according IO-APIC spec( > https://pdos.csail.mit.edu/6.828/2016/readings/ia32/ioapic.pdf). > > Signed-off-by: Lan Tianyu <Tianyu.Lan@microsoft.com> > --- > Change since v2: > - Improve comment about why save IO-APIC entry in the irq chip data. > - Some code improvement. > - Improve statement in the IOMMU Kconfig. > > Change since v1: > - Remove unused pr_fmt > - Make ioapic_ir_domain as static variable > - Remove unused variables cfg and entry in the hyperv_irq_remapping_alloc() > - Fix comments > --- > drivers/iommu/Kconfig | 8 ++ > drivers/iommu/Makefile | 1 + > drivers/iommu/hyperv-iommu.c | 194 ++++++++++++++++++++++++++++++++++++++++++ > drivers/iommu/irq_remapping.c | 3 + > drivers/iommu/irq_remapping.h | 1 + > 5 files changed, 207 insertions(+) > create mode 100644 drivers/iommu/hyperv-iommu.c > > diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig > index 45d7021..6090935 100644 > --- a/drivers/iommu/Kconfig > +++ b/drivers/iommu/Kconfig > @@ -437,4 +437,12 @@ config QCOM_IOMMU > help > Support for IOMMU on certain Qualcomm SoCs. > > +config HYPERV_IOMMU > + bool "Hyper-V x2APIC IRQ Handling" > + depends on HYPERV > + select IOMMU_API > + help > + Stub IOMMU driver to handle IRQs as to allow Hyper-V Linux > + guests to run with x2APIC mode enabled. > + > endif # IOMMU_SUPPORT > diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile > index a158a68..8c71a15 100644 > --- a/drivers/iommu/Makefile > +++ b/drivers/iommu/Makefile > @@ -32,3 +32,4 @@ obj-$(CONFIG_EXYNOS_IOMMU) += exynos-iommu.o > obj-$(CONFIG_FSL_PAMU) += fsl_pamu.o fsl_pamu_domain.o > obj-$(CONFIG_S390_IOMMU) += s390-iommu.o > obj-$(CONFIG_QCOM_IOMMU) += qcom_iommu.o > +obj-$(CONFIG_HYPERV_IOMMU) += hyperv-iommu.o > diff --git a/drivers/iommu/hyperv-iommu.c b/drivers/iommu/hyperv-iommu.c > new file mode 100644 > index 0000000..d8572c5 > --- /dev/null > +++ b/drivers/iommu/hyperv-iommu.c > @@ -0,0 +1,194 @@ > +// SPDX-License-Identifier: GPL-2.0 > + > +/* > + * Hyper-V stub IOMMU driver. > + * > + * Copyright (C) 2019, Microsoft, Inc. > + * > + * Author : Lan Tianyu <Tianyu.Lan@microsoft.com> > + */ > + > +#include <linux/types.h> > +#include <linux/interrupt.h> > +#include <linux/irq.h> > +#include <linux/iommu.h> > +#include <linux/module.h> > + > +#include <asm/hw_irq.h> > +#include <asm/io_apic.h> > +#include <asm/irq_remapping.h> > +#include <asm/hypervisor.h> > + > +#include "irq_remapping.h" > + > +#ifdef CONFIG_IRQ_REMAP > + > +/* > + * According 82093AA IO-APIC spec , IO APIC has a 24-entry Interrupt > + * Redirection Table. Hyper-V exposes one single IO-APIC and so define > + * 24 IO APIC remmapping entries. > + */ > +#define IOAPIC_REMAPPING_ENTRY 24 > + > +static cpumask_t ioapic_max_cpumask = { CPU_BITS_NONE }; > +static struct irq_domain *ioapic_ir_domain; > + > +static int hyperv_ir_set_affinity(struct irq_data *data, > + const struct cpumask *mask, bool force) > +{ > + struct irq_data *parent = data->parent_data; > + struct irq_cfg *cfg = irqd_cfg(data); > + struct IO_APIC_route_entry *entry; > + int ret; > + > + /* Return error If new irq affinity is out of ioapic_max_cpumask. */ > + if (!cpumask_subset(mask, &ioapic_max_cpumask)) > + return -EINVAL; > + > + ret = parent->chip->irq_set_affinity(parent, mask, force); > + if (ret < 0 || ret == IRQ_SET_MASK_OK_DONE) > + return ret; > + > + entry = data->chip_data; > + entry->dest = cfg->dest_apicid; > + entry->vector = cfg->vector; > + send_cleanup_vector(cfg); > + > + return 0; > +} > + > +static struct irq_chip hyperv_ir_chip = { > + .name = "HYPERV-IR", > + .irq_ack = apic_ack_irq, > + .irq_set_affinity = hyperv_ir_set_affinity, > +}; > + > +static int hyperv_irq_remapping_alloc(struct irq_domain *domain, > + unsigned int virq, unsigned int nr_irqs, > + void *arg) > +{ > + struct irq_alloc_info *info = arg; > + struct irq_data *irq_data; > + struct irq_desc *desc; > + int ret = 0; > + > + if (!info || info->type != X86_IRQ_ALLOC_TYPE_IOAPIC || nr_irqs > 1) > + return -EINVAL; > + > + ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, arg); > + if (ret < 0) > + return ret; > + > + irq_data = irq_domain_get_irq_data(domain, virq); > + if (!irq_data) { > + irq_domain_free_irqs_common(domain, virq, nr_irqs); > + return -EINVAL; > + } > + > + irq_data->chip = &hyperv_ir_chip; > + > + /* > + * If there is interrupt remapping function of IOMMU, setting irq > + * affinity only needs to change IRTE of IOMMU. But Hyper-V doesn't > + * support interrupt remapping function, setting irq affinity of IO-APIC > + * interrupts still needs to change IO-APIC registers. But ioapic_ > + * configure_entry() will ignore value of cfg->vector and cfg-> > + * dest_apicid when IO-APIC's parent irq domain is not the vector > + * domain.(See ioapic_configure_entry()) In order to setting vector > + * and dest_apicid to IO-APIC register, IO-APIC entry pointer is saved > + * in the chip_data and hyperv_irq_remapping_activate()/hyperv_ir_set_ > + * affinity() set vector and dest_apicid directly into IO-APIC entry. > + */ > + irq_data->chip_data = info->ioapic_entry; > + > + /* > + * Hypver-V IO APIC irq affinity should be in the scope of > + * ioapic_max_cpumask because no irq remapping support. > + */ > + desc = irq_data_to_desc(irq_data); > + cpumask_copy(desc->irq_common_data.affinity, &ioapic_max_cpumask); > + > + return 0; > +} > + > +static void hyperv_irq_remapping_free(struct irq_domain *domain, > + unsigned int virq, unsigned int nr_irqs) > +{ > + irq_domain_free_irqs_common(domain, virq, nr_irqs); > +} > + > +static int hyperv_irq_remapping_activate(struct irq_domain *domain, > + struct irq_data *irq_data, bool reserve) > +{ > + struct irq_cfg *cfg = irqd_cfg(irq_data); > + struct IO_APIC_route_entry *entry = irq_data->chip_data; > + > + entry->dest = cfg->dest_apicid; > + entry->vector = cfg->vector; > + > + return 0; > +} > + > +static struct irq_domain_ops hyperv_ir_domain_ops = { > + .alloc = hyperv_irq_remapping_alloc, > + .free = hyperv_irq_remapping_free, > + .activate = hyperv_irq_remapping_activate, > +}; > + > +static int __init hyperv_prepare_irq_remapping(void) > +{ > + struct fwnode_handle *fn; > + int i; > + > + if (!hypervisor_is_type(x86_hyper_type) || I think this should be if (hypervisor_is_type(X86_HYPER_MS_HYPERV)) > + !x2apic_supported()) > + return -ENODEV; > + > + fn = irq_domain_alloc_named_id_fwnode("HYPERV-IR", 0); > + if (!fn) > + return -ENOMEM; > + > + ioapic_ir_domain = > + irq_domain_create_hierarchy(arch_get_ir_parent_domain(), > + 0, IOAPIC_REMAPPING_ENTRY, fn, > + &hyperv_ir_domain_ops, NULL); > + > + irq_domain_free_fwnode(fn); > + > + /* > + * Hyper-V doesn't provide irq remapping function for > + * IO-APIC and so IO-APIC only accepts 8-bit APIC ID. > + * Cpu's APIC ID is read from ACPI MADT table and APIC IDs > + * in the MADT table on Hyper-v are sorted monotonic increasingly. > + * APIC ID reflects cpu topology. There maybe some APIC ID > + * gaps when cpu number in a socket is not power of two. Prepare > + * max cpu affinity for IOAPIC irqs. Scan cpu 0-255 and set cpu > + * into ioapic_max_cpumask if its APIC ID is less than 256. > + */ > + for (i = 0; i < 256; i++) > + if (cpu_physical_id(i) < 256) > + cpumask_set_cpu(i, &ioapic_max_cpumask); > + > + return 0; > +} > + > +static int __init hyperv_enable_irq_remapping(void) > +{ > + return IRQ_REMAP_X2APIC_MODE; > +} > + > +static struct irq_domain *hyperv_get_ir_irq_domain(struct irq_alloc_info *info) > +{ > + if (info->type == X86_IRQ_ALLOC_TYPE_IOAPIC) > + return ioapic_ir_domain; > + else > + return NULL; > +} > + > +struct irq_remap_ops hyperv_irq_remap_ops = { > + .prepare = hyperv_prepare_irq_remapping, > + .enable = hyperv_enable_irq_remapping, > + .get_ir_irq_domain = hyperv_get_ir_irq_domain, > +}; > + > +#endif > diff --git a/drivers/iommu/irq_remapping.c b/drivers/iommu/irq_remapping.c > index b94ebd4..81cf290 100644 > --- a/drivers/iommu/irq_remapping.c > +++ b/drivers/iommu/irq_remapping.c > @@ -103,6 +103,9 @@ int __init irq_remapping_prepare(void) > else if (IS_ENABLED(CONFIG_AMD_IOMMU) && > amd_iommu_irq_ops.prepare() == 0) > remap_ops = &amd_iommu_irq_ops; > + else if (IS_ENABLED(CONFIG_HYPERV_IOMMU) && > + hyperv_irq_remap_ops.prepare() == 0) > + remap_ops = &hyperv_irq_remap_ops; > else > return -ENOSYS; > > diff --git a/drivers/iommu/irq_remapping.h b/drivers/iommu/irq_remapping.h > index 0afef6e..f8609e9 100644 > --- a/drivers/iommu/irq_remapping.h > +++ b/drivers/iommu/irq_remapping.h > @@ -64,6 +64,7 @@ struct irq_remap_ops { > > extern struct irq_remap_ops intel_irq_remap_ops; > extern struct irq_remap_ops amd_iommu_irq_ops; > +extern struct irq_remap_ops hyperv_irq_remap_ops; > > #else /* CONFIG_IRQ_REMAP */ -- Vitaly ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH V3 2/3] HYPERV/IOMMU: Add Hyper-V stub IOMMU driver 2019-02-07 17:15 ` Vitaly Kuznetsov @ 2019-02-11 8:19 ` Tianyu Lan 0 siblings, 0 replies; 11+ messages in thread From: Tianyu Lan @ 2019-02-11 8:19 UTC (permalink / raw) To: Vitaly Kuznetsov Cc: Lan Tianyu, Joerg Roedel, mchehab+samsung, davem, Greg Kroah-Hartman, nicolas.ferre, Arnd Bergmann, linux-kernel@vger kernel org, iommu, michael.h.kelley, kys, Alex Williamson, Sasha Levin, Dan Carpenter On Fri, Feb 8, 2019 at 1:15 AM Vitaly Kuznetsov <vkuznets@redhat.com> wrote: > > lantianyu1986@gmail.com writes: > > > From: Lan Tianyu <Tianyu.Lan@microsoft.com> > > > > On the bare metal, enabling X2APIC mode requires interrupt remapping > > function which helps to deliver irq to cpu with 32-bit APIC ID. > > Hyper-V doesn't provide interrupt remapping function so far and Hyper-V > > MSI protocol already supports to deliver interrupt to the CPU whose > > virtual processor index is more than 255. IO-APIC interrupt still has > > 8-bit APIC ID limitation. > > > > This patch is to add Hyper-V stub IOMMU driver in order to enable > > X2APIC mode successfully in Hyper-V Linux guest. The driver returns X2APIC > > interrupt remapping capability when X2APIC mode is available. Otherwise, > > it creates a Hyper-V irq domain to limit IO-APIC interrupts' affinity > > and make sure cpus assigned with IO-APIC interrupt have 8-bit APIC ID. > > > > Define 24 IO-APIC remapping entries because Hyper-V only expose one > > single IO-APIC and one IO-APIC has 24 pins according IO-APIC spec( > > https://pdos.csail.mit.edu/6.828/2016/readings/ia32/ioapic.pdf). > > > > Signed-off-by: Lan Tianyu <Tianyu.Lan@microsoft.com> > > --- > > Change since v2: > > - Improve comment about why save IO-APIC entry in the irq chip data. > > - Some code improvement. > > - Improve statement in the IOMMU Kconfig. > > > > Change since v1: > > - Remove unused pr_fmt > > - Make ioapic_ir_domain as static variable > > - Remove unused variables cfg and entry in the hyperv_irq_remapping_alloc() > > - Fix comments > > --- > > drivers/iommu/Kconfig | 8 ++ > > drivers/iommu/Makefile | 1 + > > drivers/iommu/hyperv-iommu.c | 194 ++++++++++++++++++++++++++++++++++++++++++ > > drivers/iommu/irq_remapping.c | 3 + > > drivers/iommu/irq_remapping.h | 1 + > > 5 files changed, 207 insertions(+) > > create mode 100644 drivers/iommu/hyperv-iommu.c > > > > diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig > > index 45d7021..6090935 100644 > > --- a/drivers/iommu/Kconfig > > +++ b/drivers/iommu/Kconfig > > @@ -437,4 +437,12 @@ config QCOM_IOMMU > > help > > Support for IOMMU on certain Qualcomm SoCs. > > > > +config HYPERV_IOMMU > > + bool "Hyper-V x2APIC IRQ Handling" > > + depends on HYPERV > > + select IOMMU_API > > + help > > + Stub IOMMU driver to handle IRQs as to allow Hyper-V Linux > > + guests to run with x2APIC mode enabled. > > + > > endif # IOMMU_SUPPORT > > diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile > > index a158a68..8c71a15 100644 > > --- a/drivers/iommu/Makefile > > +++ b/drivers/iommu/Makefile > > @@ -32,3 +32,4 @@ obj-$(CONFIG_EXYNOS_IOMMU) += exynos-iommu.o > > obj-$(CONFIG_FSL_PAMU) += fsl_pamu.o fsl_pamu_domain.o > > obj-$(CONFIG_S390_IOMMU) += s390-iommu.o > > obj-$(CONFIG_QCOM_IOMMU) += qcom_iommu.o > > +obj-$(CONFIG_HYPERV_IOMMU) += hyperv-iommu.o > > diff --git a/drivers/iommu/hyperv-iommu.c b/drivers/iommu/hyperv-iommu.c > > new file mode 100644 > > index 0000000..d8572c5 > > --- /dev/null > > +++ b/drivers/iommu/hyperv-iommu.c > > @@ -0,0 +1,194 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > + > > +/* > > + * Hyper-V stub IOMMU driver. > > + * > > + * Copyright (C) 2019, Microsoft, Inc. > > + * > > + * Author : Lan Tianyu <Tianyu.Lan@microsoft.com> > > + */ > > + > > +#include <linux/types.h> > > +#include <linux/interrupt.h> > > +#include <linux/irq.h> > > +#include <linux/iommu.h> > > +#include <linux/module.h> > > + > > +#include <asm/hw_irq.h> > > +#include <asm/io_apic.h> > > +#include <asm/irq_remapping.h> > > +#include <asm/hypervisor.h> > > + > > +#include "irq_remapping.h" > > + > > +#ifdef CONFIG_IRQ_REMAP > > + > > +/* > > + * According 82093AA IO-APIC spec , IO APIC has a 24-entry Interrupt > > + * Redirection Table. Hyper-V exposes one single IO-APIC and so define > > + * 24 IO APIC remmapping entries. > > + */ > > +#define IOAPIC_REMAPPING_ENTRY 24 > > + > > +static cpumask_t ioapic_max_cpumask = { CPU_BITS_NONE }; > > +static struct irq_domain *ioapic_ir_domain; > > + > > +static int hyperv_ir_set_affinity(struct irq_data *data, > > + const struct cpumask *mask, bool force) > > +{ > > + struct irq_data *parent = data->parent_data; > > + struct irq_cfg *cfg = irqd_cfg(data); > > + struct IO_APIC_route_entry *entry; > > + int ret; > > + > > + /* Return error If new irq affinity is out of ioapic_max_cpumask. */ > > + if (!cpumask_subset(mask, &ioapic_max_cpumask)) > > + return -EINVAL; > > + > > + ret = parent->chip->irq_set_affinity(parent, mask, force); > > + if (ret < 0 || ret == IRQ_SET_MASK_OK_DONE) > > + return ret; > > + > > + entry = data->chip_data; > > + entry->dest = cfg->dest_apicid; > > + entry->vector = cfg->vector; > > + send_cleanup_vector(cfg); > > + > > + return 0; > > +} > > + > > +static struct irq_chip hyperv_ir_chip = { > > + .name = "HYPERV-IR", > > + .irq_ack = apic_ack_irq, > > + .irq_set_affinity = hyperv_ir_set_affinity, > > +}; > > + > > +static int hyperv_irq_remapping_alloc(struct irq_domain *domain, > > + unsigned int virq, unsigned int nr_irqs, > > + void *arg) > > +{ > > + struct irq_alloc_info *info = arg; > > + struct irq_data *irq_data; > > + struct irq_desc *desc; > > + int ret = 0; > > + > > + if (!info || info->type != X86_IRQ_ALLOC_TYPE_IOAPIC || nr_irqs > 1) > > + return -EINVAL; > > + > > + ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, arg); > > + if (ret < 0) > > + return ret; > > + > > + irq_data = irq_domain_get_irq_data(domain, virq); > > + if (!irq_data) { > > + irq_domain_free_irqs_common(domain, virq, nr_irqs); > > + return -EINVAL; > > + } > > + > > + irq_data->chip = &hyperv_ir_chip; > > + > > + /* > > + * If there is interrupt remapping function of IOMMU, setting irq > > + * affinity only needs to change IRTE of IOMMU. But Hyper-V doesn't > > + * support interrupt remapping function, setting irq affinity of IO-APIC > > + * interrupts still needs to change IO-APIC registers. But ioapic_ > > + * configure_entry() will ignore value of cfg->vector and cfg-> > > + * dest_apicid when IO-APIC's parent irq domain is not the vector > > + * domain.(See ioapic_configure_entry()) In order to setting vector > > + * and dest_apicid to IO-APIC register, IO-APIC entry pointer is saved > > + * in the chip_data and hyperv_irq_remapping_activate()/hyperv_ir_set_ > > + * affinity() set vector and dest_apicid directly into IO-APIC entry. > > + */ > > + irq_data->chip_data = info->ioapic_entry; > > + > > + /* > > + * Hypver-V IO APIC irq affinity should be in the scope of > > + * ioapic_max_cpumask because no irq remapping support. > > + */ > > + desc = irq_data_to_desc(irq_data); > > + cpumask_copy(desc->irq_common_data.affinity, &ioapic_max_cpumask); > > + > > + return 0; > > +} > > + > > +static void hyperv_irq_remapping_free(struct irq_domain *domain, > > + unsigned int virq, unsigned int nr_irqs) > > +{ > > + irq_domain_free_irqs_common(domain, virq, nr_irqs); > > +} > > + > > +static int hyperv_irq_remapping_activate(struct irq_domain *domain, > > + struct irq_data *irq_data, bool reserve) > > +{ > > + struct irq_cfg *cfg = irqd_cfg(irq_data); > > + struct IO_APIC_route_entry *entry = irq_data->chip_data; > > + > > + entry->dest = cfg->dest_apicid; > > + entry->vector = cfg->vector; > > + > > + return 0; > > +} > > + > > +static struct irq_domain_ops hyperv_ir_domain_ops = { > > + .alloc = hyperv_irq_remapping_alloc, > > + .free = hyperv_irq_remapping_free, > > + .activate = hyperv_irq_remapping_activate, > > +}; > > + > > +static int __init hyperv_prepare_irq_remapping(void) > > +{ > > + struct fwnode_handle *fn; > > + int i; > > + > > + if (!hypervisor_is_type(x86_hyper_type) || > > I think this should be > > if (hypervisor_is_type(X86_HYPER_MS_HYPERV)) Sorry for oops and will fix in the next version. Thanks. > > > + !x2apic_supported()) > > + return -ENODEV; > > + > > + fn = irq_domain_alloc_named_id_fwnode("HYPERV-IR", 0); > > + if (!fn) > > + return -ENOMEM; > > + > > + ioapic_ir_domain = > > + irq_domain_create_hierarchy(arch_get_ir_parent_domain(), > > + 0, IOAPIC_REMAPPING_ENTRY, fn, > > + &hyperv_ir_domain_ops, NULL); > > + > > + irq_domain_free_fwnode(fn); > > + > > + /* > > + * Hyper-V doesn't provide irq remapping function for > > + * IO-APIC and so IO-APIC only accepts 8-bit APIC ID. > > + * Cpu's APIC ID is read from ACPI MADT table and APIC IDs > > + * in the MADT table on Hyper-v are sorted monotonic increasingly. > > + * APIC ID reflects cpu topology. There maybe some APIC ID > > + * gaps when cpu number in a socket is not power of two. Prepare > > + * max cpu affinity for IOAPIC irqs. Scan cpu 0-255 and set cpu > > + * into ioapic_max_cpumask if its APIC ID is less than 256. > > + */ > > + for (i = 0; i < 256; i++) > > + if (cpu_physical_id(i) < 256) > > + cpumask_set_cpu(i, &ioapic_max_cpumask); > > + > > + return 0; > > +} > > + > > +static int __init hyperv_enable_irq_remapping(void) > > +{ > > + return IRQ_REMAP_X2APIC_MODE; > > +} > > + > > +static struct irq_domain *hyperv_get_ir_irq_domain(struct irq_alloc_info *info) > > +{ > > + if (info->type == X86_IRQ_ALLOC_TYPE_IOAPIC) > > + return ioapic_ir_domain; > > + else > > + return NULL; > > +} > > + > > +struct irq_remap_ops hyperv_irq_remap_ops = { > > + .prepare = hyperv_prepare_irq_remapping, > > + .enable = hyperv_enable_irq_remapping, > > + .get_ir_irq_domain = hyperv_get_ir_irq_domain, > > +}; > > + > > +#endif > > diff --git a/drivers/iommu/irq_remapping.c b/drivers/iommu/irq_remapping.c > > index b94ebd4..81cf290 100644 > > --- a/drivers/iommu/irq_remapping.c > > +++ b/drivers/iommu/irq_remapping.c > > @@ -103,6 +103,9 @@ int __init irq_remapping_prepare(void) > > else if (IS_ENABLED(CONFIG_AMD_IOMMU) && > > amd_iommu_irq_ops.prepare() == 0) > > remap_ops = &amd_iommu_irq_ops; > > + else if (IS_ENABLED(CONFIG_HYPERV_IOMMU) && > > + hyperv_irq_remap_ops.prepare() == 0) > > + remap_ops = &hyperv_irq_remap_ops; > > else > > return -ENOSYS; > > > > diff --git a/drivers/iommu/irq_remapping.h b/drivers/iommu/irq_remapping.h > > index 0afef6e..f8609e9 100644 > > --- a/drivers/iommu/irq_remapping.h > > +++ b/drivers/iommu/irq_remapping.h > > @@ -64,6 +64,7 @@ struct irq_remap_ops { > > > > extern struct irq_remap_ops intel_irq_remap_ops; > > extern struct irq_remap_ops amd_iommu_irq_ops; > > +extern struct irq_remap_ops hyperv_irq_remap_ops; > > > > #else /* CONFIG_IRQ_REMAP */ > > -- > Vitaly -- Best regards Tianyu Lan ^ permalink raw reply [flat|nested] 11+ messages in thread
[parent not found: <1549553629-8414-3-git-send-email-Tianyu.Lan-0li6OtcxBFHby3iVrkZq2A@public.gmane.org>]
* Re: [PATCH V3 2/3] HYPERV/IOMMU: Add Hyper-V stub IOMMU driver [not found] ` <1549553629-8414-3-git-send-email-Tianyu.Lan-0li6OtcxBFHby3iVrkZq2A@public.gmane.org> @ 2019-02-07 18:15 ` Alex Williamson 2019-02-11 8:10 ` Tianyu Lan 0 siblings, 1 reply; 11+ messages in thread From: Alex Williamson @ 2019-02-07 18:15 UTC (permalink / raw) To: lantianyu1986-Re5JQEeQqe8AvxtiuMwx3w Cc: sashal-DgEjT+Ai2ygdnm+yROfE0A, Lan Tianyu, arnd-r2nGTMty4D4, gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r, nicolas.ferre-UWL1GkI3JZL3oGB3hsPCZA, linux-kernel-u79uwXL29TY76Z2rM5mHXA, michael.h.kelley-0li6OtcxBFHby3iVrkZq2A, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA, mchehab+samsung-DgEjT+Ai2ygdnm+yROfE0A, vkuznets-H+wXaHxf7aLQT0dZR+AlfA, kys-0li6OtcxBFHby3iVrkZq2A, davem-fT/PcQaiUtIeIZ0/mPfg9Q, dan.carpenter-QHcLZuEGTsvQT0dZR+AlfA On Thu, 7 Feb 2019 23:33:48 +0800 lantianyu1986-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org wrote: > From: Lan Tianyu <Tianyu.Lan-0li6OtcxBFHby3iVrkZq2A@public.gmane.org> > > On the bare metal, enabling X2APIC mode requires interrupt remapping > function which helps to deliver irq to cpu with 32-bit APIC ID. > Hyper-V doesn't provide interrupt remapping function so far and Hyper-V > MSI protocol already supports to deliver interrupt to the CPU whose > virtual processor index is more than 255. IO-APIC interrupt still has > 8-bit APIC ID limitation. > > This patch is to add Hyper-V stub IOMMU driver in order to enable > X2APIC mode successfully in Hyper-V Linux guest. The driver returns X2APIC > interrupt remapping capability when X2APIC mode is available. Otherwise, > it creates a Hyper-V irq domain to limit IO-APIC interrupts' affinity > and make sure cpus assigned with IO-APIC interrupt have 8-bit APIC ID. > > Define 24 IO-APIC remapping entries because Hyper-V only expose one > single IO-APIC and one IO-APIC has 24 pins according IO-APIC spec( > https://pdos.csail.mit.edu/6.828/2016/readings/ia32/ioapic.pdf). > > Signed-off-by: Lan Tianyu <Tianyu.Lan-0li6OtcxBFHby3iVrkZq2A@public.gmane.org> > --- > Change since v2: > - Improve comment about why save IO-APIC entry in the irq chip data. > - Some code improvement. > - Improve statement in the IOMMU Kconfig. > > Change since v1: > - Remove unused pr_fmt > - Make ioapic_ir_domain as static variable > - Remove unused variables cfg and entry in the hyperv_irq_remapping_alloc() > - Fix comments > --- > drivers/iommu/Kconfig | 8 ++ > drivers/iommu/Makefile | 1 + > drivers/iommu/hyperv-iommu.c | 194 ++++++++++++++++++++++++++++++++++++++++++ > drivers/iommu/irq_remapping.c | 3 + > drivers/iommu/irq_remapping.h | 1 + > 5 files changed, 207 insertions(+) > create mode 100644 drivers/iommu/hyperv-iommu.c ... > diff --git a/drivers/iommu/hyperv-iommu.c b/drivers/iommu/hyperv-iommu.c > new file mode 100644 > index 0000000..d8572c5 > --- /dev/null > +++ b/drivers/iommu/hyperv-iommu.c ... > +static int __init hyperv_prepare_irq_remapping(void) > +{ > + struct fwnode_handle *fn; > + int i; > + > + if (!hypervisor_is_type(x86_hyper_type) || > + !x2apic_supported()) > + return -ENODEV; > + > + fn = irq_domain_alloc_named_id_fwnode("HYPERV-IR", 0); > + if (!fn) > + return -ENOMEM; > + > + ioapic_ir_domain = > + irq_domain_create_hierarchy(arch_get_ir_parent_domain(), > + 0, IOAPIC_REMAPPING_ENTRY, fn, > + &hyperv_ir_domain_ops, NULL); > + > + irq_domain_free_fwnode(fn); > + > + /* > + * Hyper-V doesn't provide irq remapping function for > + * IO-APIC and so IO-APIC only accepts 8-bit APIC ID. > + * Cpu's APIC ID is read from ACPI MADT table and APIC IDs > + * in the MADT table on Hyper-v are sorted monotonic increasingly. > + * APIC ID reflects cpu topology. There maybe some APIC ID > + * gaps when cpu number in a socket is not power of two. Prepare > + * max cpu affinity for IOAPIC irqs. Scan cpu 0-255 and set cpu > + * into ioapic_max_cpumask if its APIC ID is less than 256. > + */ > + for (i = 0; i < 256; i++) > + if (cpu_physical_id(i) < 256) > + cpumask_set_cpu(i, &ioapic_max_cpumask); This looks sketchy. What if NR_CPUS is less than 256? Thanks, Alex > + > + return 0; > +} ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH V3 2/3] HYPERV/IOMMU: Add Hyper-V stub IOMMU driver 2019-02-07 18:15 ` Alex Williamson @ 2019-02-11 8:10 ` Tianyu Lan 0 siblings, 0 replies; 11+ messages in thread From: Tianyu Lan @ 2019-02-11 8:10 UTC (permalink / raw) To: Alex Williamson Cc: Lan Tianyu, Joerg Roedel, mchehab+samsung, davem, Greg Kroah-Hartman, nicolas.ferre, Arnd Bergmann, linux-kernel@vger kernel org, iommu, michael.h.kelley, kys, Vitaly Kuznetsov, Sasha Levin, Dan Carpenter Hi Alex: Thanks for your review. On Fri, Feb 8, 2019 at 2:15 AM Alex Williamson <alex.williamson@redhat.com> wrote: > > On Thu, 7 Feb 2019 23:33:48 +0800 > lantianyu1986@gmail.com wrote: > > > From: Lan Tianyu <Tianyu.Lan@microsoft.com> > > > > On the bare metal, enabling X2APIC mode requires interrupt remapping > > function which helps to deliver irq to cpu with 32-bit APIC ID. > > Hyper-V doesn't provide interrupt remapping function so far and Hyper-V > > MSI protocol already supports to deliver interrupt to the CPU whose > > virtual processor index is more than 255. IO-APIC interrupt still has > > 8-bit APIC ID limitation. > > > > This patch is to add Hyper-V stub IOMMU driver in order to enable > > X2APIC mode successfully in Hyper-V Linux guest. The driver returns X2APIC > > interrupt remapping capability when X2APIC mode is available. Otherwise, > > it creates a Hyper-V irq domain to limit IO-APIC interrupts' affinity > > and make sure cpus assigned with IO-APIC interrupt have 8-bit APIC ID. > > > > Define 24 IO-APIC remapping entries because Hyper-V only expose one > > single IO-APIC and one IO-APIC has 24 pins according IO-APIC spec( > > https://pdos.csail.mit.edu/6.828/2016/readings/ia32/ioapic.pdf). > > > > Signed-off-by: Lan Tianyu <Tianyu.Lan@microsoft.com> > > --- > > Change since v2: > > - Improve comment about why save IO-APIC entry in the irq chip data. > > - Some code improvement. > > - Improve statement in the IOMMU Kconfig. > > > > Change since v1: > > - Remove unused pr_fmt > > - Make ioapic_ir_domain as static variable > > - Remove unused variables cfg and entry in the hyperv_irq_remapping_alloc() > > - Fix comments > > --- > > drivers/iommu/Kconfig | 8 ++ > > drivers/iommu/Makefile | 1 + > > drivers/iommu/hyperv-iommu.c | 194 ++++++++++++++++++++++++++++++++++++++++++ > > drivers/iommu/irq_remapping.c | 3 + > > drivers/iommu/irq_remapping.h | 1 + > > 5 files changed, 207 insertions(+) > > create mode 100644 drivers/iommu/hyperv-iommu.c > ... > > diff --git a/drivers/iommu/hyperv-iommu.c b/drivers/iommu/hyperv-iommu.c > > new file mode 100644 > > index 0000000..d8572c5 > > --- /dev/null > > +++ b/drivers/iommu/hyperv-iommu.c > ... > > +static int __init hyperv_prepare_irq_remapping(void) > > +{ > > + struct fwnode_handle *fn; > > + int i; > > + > > + if (!hypervisor_is_type(x86_hyper_type) || > > + !x2apic_supported()) > > + return -ENODEV; > > + > > + fn = irq_domain_alloc_named_id_fwnode("HYPERV-IR", 0); > > + if (!fn) > > + return -ENOMEM; > > + > > + ioapic_ir_domain = > > + irq_domain_create_hierarchy(arch_get_ir_parent_domain(), > > + 0, IOAPIC_REMAPPING_ENTRY, fn, > > + &hyperv_ir_domain_ops, NULL); > > + > > + irq_domain_free_fwnode(fn); > > + > > + /* > > + * Hyper-V doesn't provide irq remapping function for > > + * IO-APIC and so IO-APIC only accepts 8-bit APIC ID. > > + * Cpu's APIC ID is read from ACPI MADT table and APIC IDs > > + * in the MADT table on Hyper-v are sorted monotonic increasingly. > > + * APIC ID reflects cpu topology. There maybe some APIC ID > > + * gaps when cpu number in a socket is not power of two. Prepare > > + * max cpu affinity for IOAPIC irqs. Scan cpu 0-255 and set cpu > > + * into ioapic_max_cpumask if its APIC ID is less than 256. > > + */ > > + for (i = 0; i < 256; i++) > > + if (cpu_physical_id(i) < 256) > > + cpumask_set_cpu(i, &ioapic_max_cpumask); > > This looks sketchy. What if NR_CPUS is less than 256? Thanks, Nice catch. I should check NR_CPUS here. Will update. Thanks. -- Best regards Tianyu Lan ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH V3 2/3] HYPERV/IOMMU: Add Hyper-V stub IOMMU driver 2019-02-07 15:33 ` [PATCH V3 2/3] HYPERV/IOMMU: Add Hyper-V stub IOMMU driver lantianyu1986 2019-02-07 17:15 ` Vitaly Kuznetsov [not found] ` <1549553629-8414-3-git-send-email-Tianyu.Lan-0li6OtcxBFHby3iVrkZq2A@public.gmane.org> @ 2019-02-08 14:51 ` Olaf Hering 2019-02-11 8:21 ` Tianyu Lan 2 siblings, 1 reply; 11+ messages in thread From: Olaf Hering @ 2019-02-08 14:51 UTC (permalink / raw) To: lantianyu1986 Cc: Lan Tianyu, linux-kernel, iommu, michael.h.kelley, kys, vkuznets, alex.williamson, sashal, dan.carpenter [-- Attachment #1: Type: text/plain, Size: 272 bytes --] On Thu, Feb 07, lantianyu1986@gmail.com wrote: > +++ b/drivers/iommu/Kconfig > +config HYPERV_IOMMU > + bool "Hyper-V x2APIC IRQ Handling" > + depends on HYPERV > + select IOMMU_API > + help Consider adding 'default HYPERV' like some other drivers already do it. Olaf [-- Attachment #2: signature.asc --] [-- Type: application/pgp-signature, Size: 195 bytes --] ^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH V3 2/3] HYPERV/IOMMU: Add Hyper-V stub IOMMU driver 2019-02-08 14:51 ` Olaf Hering @ 2019-02-11 8:21 ` Tianyu Lan 0 siblings, 0 replies; 11+ messages in thread From: Tianyu Lan @ 2019-02-11 8:21 UTC (permalink / raw) To: Olaf Hering Cc: Lan Tianyu, linux-kernel@vger kernel org, iommu, michael.h.kelley, kys, Vitaly Kuznetsov, Alex Williamson, Sasha Levin, Dan Carpenter Hi Olaf: Thanks for your review. On Fri, Feb 8, 2019 at 10:52 PM Olaf Hering <olaf@aepfle.de> wrote: > > On Thu, Feb 07, lantianyu1986@gmail.com wrote: > > > +++ b/drivers/iommu/Kconfig > > +config HYPERV_IOMMU > > + bool "Hyper-V x2APIC IRQ Handling" > > + depends on HYPERV > > + select IOMMU_API > > + help > > > Consider adding 'default HYPERV' like some other drivers already do it. > > Olaf Good suggestion and will update. Thanks. -- Best regards Tianyu Lan ^ permalink raw reply [flat|nested] 11+ messages in thread
end of thread, other threads:[~2019-02-11 8:21 UTC | newest] Thread overview: 11+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2019-02-07 15:33 [PATCH V3 0/3] x86/Hyper-V/IOMMU: Add Hyper-V IOMMU driver to support x2apic mode lantianyu1986 [not found] ` <1549553629-8414-1-git-send-email-Tianyu.Lan-0li6OtcxBFHby3iVrkZq2A@public.gmane.org> 2019-02-07 15:33 ` [PATCH V3 1/3] x86/Hyper-V: Set x2apic destination mode to physical when x2apic is available lantianyu1986-Re5JQEeQqe8AvxtiuMwx3w 2019-02-10 21:48 ` Thomas Gleixner 2019-02-11 8:05 ` Tianyu Lan 2019-02-07 15:33 ` [PATCH V3 2/3] HYPERV/IOMMU: Add Hyper-V stub IOMMU driver lantianyu1986 2019-02-07 17:15 ` Vitaly Kuznetsov 2019-02-11 8:19 ` Tianyu Lan [not found] ` <1549553629-8414-3-git-send-email-Tianyu.Lan-0li6OtcxBFHby3iVrkZq2A@public.gmane.org> 2019-02-07 18:15 ` Alex Williamson 2019-02-11 8:10 ` Tianyu Lan 2019-02-08 14:51 ` Olaf Hering 2019-02-11 8:21 ` Tianyu Lan
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