kernel_optimize_test/drivers/iommu/irq_remapping.h
Lan Tianyu 29217a4746 iommu/hyper-v: Add Hyper-V stub IOMMU driver
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).

Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Lan Tianyu <Tianyu.Lan@microsoft.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-02-28 11:12:16 +01:00

78 lines
2.2 KiB
C

/*
* Copyright (C) 2012 Advanced Micro Devices, Inc.
* Author: Joerg Roedel <jroedel@suse.de>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* This header file contains stuff that is shared between different interrupt
* remapping drivers but with no need to be visible outside of the IOMMU layer.
*/
#ifndef __IRQ_REMAPPING_H
#define __IRQ_REMAPPING_H
#ifdef CONFIG_IRQ_REMAP
struct irq_data;
struct msi_msg;
struct irq_domain;
struct irq_alloc_info;
extern int irq_remap_broken;
extern int disable_sourceid_checking;
extern int no_x2apic_optout;
extern int irq_remapping_enabled;
extern int disable_irq_post;
struct irq_remap_ops {
/* The supported capabilities */
int capability;
/* Initializes hardware and makes it ready for remapping interrupts */
int (*prepare)(void);
/* Enables the remapping hardware */
int (*enable)(void);
/* Disables the remapping hardware */
void (*disable)(void);
/* Reenables the remapping hardware */
int (*reenable)(int);
/* Enable fault handling */
int (*enable_faulting)(void);
/* Get the irqdomain associated the IOMMU device */
struct irq_domain *(*get_ir_irq_domain)(struct irq_alloc_info *);
/* Get the MSI irqdomain associated with the IOMMU device */
struct irq_domain *(*get_irq_domain)(struct irq_alloc_info *);
};
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 */
#define irq_remapping_enabled 0
#define irq_remap_broken 0
#define disable_irq_post 1
#endif /* CONFIG_IRQ_REMAP */
#endif /* __IRQ_REMAPPING_H */