From: Lan Tianyu <[email protected]>
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
From: Lan Tianyu <[email protected]>
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 <[email protected]>
---
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 <[email protected]>
+ */
+
+#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
From: Lan Tianyu <[email protected]>
This patch is to add Hyper-V IOMMU driver file into Hyper-V CORE and
DRIVERS scope.
Signed-off-by: Lan Tianyu <[email protected]>
---
MAINTAINERS | 1 +
1 file changed, 1 insertion(+)
diff --git a/MAINTAINERS b/MAINTAINERS
index 9f64f8d..5fb6306 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7015,6 +7015,7 @@ F: drivers/net/hyperv/
F: drivers/scsi/storvsc_drv.c
F: drivers/uio/uio_hv_generic.c
F: drivers/video/fbdev/hyperv_fb.c
+F: drivers/iommu/hyperv_iommu.c
F: net/vmw_vsock/hyperv_transport.c
F: include/linux/hyperv.h
F: include/uapi/linux/hyperv.h
--
2.7.4
From: Lan Tianyu <[email protected]>
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 <[email protected]>
---
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
[email protected] writes:
> From: Lan Tianyu <[email protected]>
>
> 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 <[email protected]>
> ---
> 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 <[email protected]>
> + */
> +
> +#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
On Thu, 7 Feb 2019 23:33:48 +0800
[email protected] wrote:
> From: Lan Tianyu <[email protected]>
>
> 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 <[email protected]>
> ---
> 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;
> +}
On Thu, Feb 07, [email protected] 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
On Thu, 7 Feb 2019, [email protected] wrote:
> From: Lan Tianyu <[email protected]>
>
> 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 <[email protected]>
If not, I just queue if for 5.1. Let me know,
Thanks,
tglx
Hi Thomas:
Thanks for your review.
On Mon, Feb 11, 2019 at 5:48 AM Thomas Gleixner <[email protected]> wrote:
>
> On Thu, 7 Feb 2019, [email protected] wrote:
>
> > From: Lan Tianyu <[email protected]>
> >
> > 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 <[email protected]>
>
> If not, I just queue if for 5.1. Let me know,
>
This patch can be applied independently. Thanks.
--
Best regards
Tianyu Lan
Hi Alex:
Thanks for your review.
On Fri, Feb 8, 2019 at 2:15 AM Alex Williamson
<[email protected]> wrote:
>
> On Thu, 7 Feb 2019 23:33:48 +0800
> [email protected] wrote:
>
> > From: Lan Tianyu <[email protected]>
> >
> > 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 <[email protected]>
> > ---
> > 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
On Fri, Feb 8, 2019 at 1:15 AM Vitaly Kuznetsov <[email protected]> wrote:
>
> [email protected] writes:
>
> > From: Lan Tianyu <[email protected]>
> >
> > 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 <[email protected]>
> > ---
> > 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 <[email protected]>
> > + */
> > +
> > +#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
Hi Olaf:
Thanks for your review.
On Fri, Feb 8, 2019 at 10:52 PM Olaf Hering <[email protected]> wrote:
>
> On Thu, Feb 07, [email protected] 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