[PATCH v7 03/15] irq: move IRQ routing into irq.c
Andre Przywara
andre.przywara at arm.com
Fri Nov 4 10:35:13 PDT 2016
Hi Jean-Philippe,
On 02/11/16 14:37, Jean-Philippe Brucker wrote:
> On 20/07/16 18:04, Andre Przywara wrote:
>> The current IRQ routing code in x86/irq.c is mostly implementing a
>> generic KVM interface which other architectures may use too.
>> Move the code to set up an MSI route into the generic irq.c file and
>> guard it with the KVM_CAP_IRQ_ROUTING capability to return an error
>> if the kernel does not support interrupt routing.
>> This also removes the dummy implementations for all other
>> architectures and only leaves the x86 specific code in x86/irq.c.
>>
>> Signed-off-by: Andre Przywara <andre.przywara at arm.com>
>> ---
>> Makefile | 4 +--
>> arm/irq.c | 9 ------
>> hw/pci-shmem.c | 2 ++
>> include/kvm/irq.h | 5 ++++
>> irq.c | 83 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
>> mips/irq.c | 10 -------
>> powerpc/irq.c | 31 ---------------------
>> virtio/pci.c | 21 +++++++++-----
>> x86/irq.c | 45 ++++--------------------------
>> 9 files changed, 110 insertions(+), 100 deletions(-)
>> delete mode 100644 arm/irq.c
>> delete mode 100644 mips/irq.c
>> delete mode 100644 powerpc/irq.c
>>
>> diff --git a/Makefile b/Makefile
>> index e4a4002..8ca887f 100644
>> --- a/Makefile
>> +++ b/Makefile
>> @@ -138,7 +138,6 @@ ifeq ($(ARCH), powerpc)
>> DEFINES += -DCONFIG_PPC
>> OBJS += powerpc/boot.o
>> OBJS += powerpc/ioport.o
>> - OBJS += powerpc/irq.o
>> OBJS += powerpc/kvm.o
>> OBJS += powerpc/cpu_info.o
>> OBJS += powerpc/kvm-cpu.o
>> @@ -153,7 +152,7 @@ ifeq ($(ARCH), powerpc)
>> endif
>>
>> # ARM
>> -OBJS_ARM_COMMON := arm/fdt.o arm/gic.o arm/ioport.o arm/irq.o \
>> +OBJS_ARM_COMMON := arm/fdt.o arm/gic.o arm/ioport.o \
>> arm/kvm.o arm/kvm-cpu.o arm/pci.o arm/timer.o \
>> arm/pmu.o
>> HDRS_ARM_COMMON := arm/include
>> @@ -186,7 +185,6 @@ ifeq ($(ARCH),mips)
>> ARCH_INCLUDE := mips/include
>> OBJS += mips/kvm.o
>> OBJS += mips/kvm-cpu.o
>> - OBJS += mips/irq.o
>> endif
>> ###
>>
>> diff --git a/arm/irq.c b/arm/irq.c
>> deleted file mode 100644
>> index d8f44df..0000000
>> --- a/arm/irq.c
>> +++ /dev/null
>> @@ -1,9 +0,0 @@
>> -#include "kvm/irq.h"
>> -#include "kvm/kvm.h"
>> -#include "kvm/util.h"
>> -
>> -int irq__add_msix_route(struct kvm *kvm, struct msi_msg *msg)
>> -{
>> - die(__FUNCTION__);
>> - return 0;
>> -}
>> diff --git a/hw/pci-shmem.c b/hw/pci-shmem.c
>> index a1c5ab7..7ce98cb 100644
>> --- a/hw/pci-shmem.c
>> +++ b/hw/pci-shmem.c
>> @@ -136,6 +136,8 @@ int pci_shmem__get_local_irqfd(struct kvm *kvm)
>>
>> if (pci_shmem_pci_device.msix.ctrl & cpu_to_le16(PCI_MSIX_FLAGS_ENABLE)) {
>> gsi = irq__add_msix_route(kvm, &msix_table[0].msg);
>> + if (gsi < 0)
>> + return gsi;
>> } else {
>> gsi = pci_shmem_pci_device.irq_line;
>> }
>> diff --git a/include/kvm/irq.h b/include/kvm/irq.h
>> index 8a78e43..bb71521 100644
>> --- a/include/kvm/irq.h
>> +++ b/include/kvm/irq.h
>> @@ -10,11 +10,16 @@
>>
>> struct kvm;
>>
>> +extern struct kvm_irq_routing *irq_routing;
>> +extern int next_gsi;
>> +
>> int irq__alloc_line(void);
>> int irq__get_nr_allocated_lines(void);
>>
>> int irq__init(struct kvm *kvm);
>> int irq__exit(struct kvm *kvm);
>> +
>> +int irq__allocate_routing_entry(void);
>> int irq__add_msix_route(struct kvm *kvm, struct msi_msg *msg);
>>
>> #endif
>> diff --git a/irq.c b/irq.c
>> index 71eaa05..c4b481c 100644
>> --- a/irq.c
>> +++ b/irq.c
>> @@ -1,7 +1,19 @@
>> +#include <stdlib.h>
>> +#include <sys/ioctl.h>
>> +#include <linux/types.h>
>> +#include <linux/kvm.h>
>> +#include <errno.h>
>> +
>> +#include "kvm/kvm.h"
>> #include "kvm/irq.h"
>> #include "kvm/kvm-arch.h"
>>
>> static u8 next_line = KVM_IRQ_OFFSET;
>> +static int allocated_gsis = 0;
>> +
>> +int next_gsi;
>> +
>> +struct kvm_irq_routing *irq_routing = NULL;
>>
>> int irq__alloc_line(void)
>> {
>> @@ -12,3 +24,74 @@ int irq__get_nr_allocated_lines(void)
>> {
>> return next_line - KVM_IRQ_OFFSET;
>> }
>> +
>> +int irq__allocate_routing_entry(void)
>> +{
>> + size_t table_size = sizeof(struct kvm_irq_routing);
>> + int nr_entries = 0;
>> +
>> + if (irq_routing)
>> + nr_entries = irq_routing->nr;
>> +
>> + if (nr_entries < allocated_gsis)
>> + return 0;
>> +
>> + allocated_gsis = ALIGN(nr_entries + 1, 32);
>> + table_size += sizeof(struct kvm_irq_routing_entry) * allocated_gsis;
>> + irq_routing = realloc(irq_routing, table_size);
>> +
>> + if (irq_routing == NULL)
>> + return ENOMEM;
>
> This should be -ENOMEM. Otherwise when allocate_routing_entry fails,
> add_msix_route will return this positive value, which the caller will
> confuse with a GSI number.
Nice catch! Thanks for that.
I fixed the patch and sent out a v8 (which has one or two more fixes).
Cheers,
Andre.
>> +
>> + irq_routing->nr = nr_entries;
>> +
>> + return 0;
>> +}
>> +
>> +static bool check_for_irq_routing(struct kvm *kvm)
>> +{
>> + static int has_irq_routing = 0;
>> +
>> + if (has_irq_routing == 0) {
>> + if (kvm__supports_extension(kvm, KVM_CAP_IRQ_ROUTING))
>> + has_irq_routing = 1;
>> + else
>> + has_irq_routing = -1;
>> + }
>> +
>> + return has_irq_routing > 0;
>> +}
>> +
>> +int irq__add_msix_route(struct kvm *kvm, struct msi_msg *msg)
>> +{
>> + int r;
>> +
>> + if (!check_for_irq_routing(kvm))
>> + return -ENXIO;
>> +
>> + r = irq__allocate_routing_entry();
>> + if (r)
>> + return r;
>> +
>> + irq_routing->entries[irq_routing->nr++] =
>> + (struct kvm_irq_routing_entry) {
>> + .gsi = next_gsi,
>> + .type = KVM_IRQ_ROUTING_MSI,
>> + .u.msi.address_hi = msg->address_hi,
>> + .u.msi.address_lo = msg->address_lo,
>> + .u.msi.data = msg->data,
>> + };
>> +
>> + r = ioctl(kvm->vm_fd, KVM_SET_GSI_ROUTING, irq_routing);
>> + if (r)
>> + return r;
>> +
>> + return next_gsi++;
>> +}
>> +
>> +int __attribute__((weak)) irq__exit(struct kvm *kvm)
>> +{
>> + free(irq_routing);
>> + return 0;
>> +}
>> +dev_base_exit(irq__exit);
>> diff --git a/mips/irq.c b/mips/irq.c
>> deleted file mode 100644
>> index c1ff6bb..0000000
>> --- a/mips/irq.c
>> +++ /dev/null
>> @@ -1,10 +0,0 @@
>> -#include "kvm/irq.h"
>> -#include "kvm/kvm.h"
>> -
>> -#include <stdlib.h>
>> -
>> -int irq__add_msix_route(struct kvm *kvm, struct msi_msg *msg)
>> -{
>> - pr_warning("irq__add_msix_route");
>> - return 1;
>> -}
>> diff --git a/powerpc/irq.c b/powerpc/irq.c
>> deleted file mode 100644
>> index 03f2fe7..0000000
>> --- a/powerpc/irq.c
>> +++ /dev/null
>> @@ -1,31 +0,0 @@
>> -/*
>> - * PPC64 IRQ routines
>> - *
>> - * Copyright 2011 Matt Evans <matt at ozlabs.org>, IBM Corporation.
>> - *
>> - * 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.
>> - */
>> -
>> -#include "kvm/devices.h"
>> -#include "kvm/irq.h"
>> -#include "kvm/kvm.h"
>> -#include "kvm/util.h"
>> -
>> -#include <linux/types.h>
>> -#include <linux/rbtree.h>
>> -#include <linux/list.h>
>> -#include <linux/kvm.h>
>> -#include <sys/ioctl.h>
>> -
>> -#include <stddef.h>
>> -#include <stdlib.h>
>> -
>> -#include "kvm/pci.h"
>> -
>> -int irq__add_msix_route(struct kvm *kvm, struct msi_msg *msg)
>> -{
>> - die(__FUNCTION__);
>> - return 0;
>> -}
>> diff --git a/virtio/pci.c b/virtio/pci.c
>> index 90fcd64..072e5b7 100644
>> --- a/virtio/pci.c
>> +++ b/virtio/pci.c
>> @@ -156,7 +156,8 @@ static bool virtio_pci__specific_io_out(struct kvm *kvm, struct virtio_device *v
>> void *data, int size, int offset)
>> {
>> struct virtio_pci *vpci = vdev->virtio;
>> - u32 config_offset, gsi, vec;
>> + u32 config_offset, vec;
>> + int gsi;
>> int type = virtio__get_dev_specific_field(offset - 20, virtio_pci__msix_enabled(vpci),
>> &config_offset);
>> if (type == VIRTIO_PCI_O_MSIX) {
>> @@ -166,21 +167,27 @@ static bool virtio_pci__specific_io_out(struct kvm *kvm, struct virtio_device *v
>> if (vec == VIRTIO_MSI_NO_VECTOR)
>> break;
>>
>> - gsi = irq__add_msix_route(kvm, &vpci->msix_table[vec].msg);
>> -
>> - vpci->config_gsi = gsi;
>> + gsi = irq__add_msix_route(kvm,
>> + &vpci->msix_table[vec].msg);
>> + if (gsi >= 0)
>> + vpci->config_gsi = gsi;
>> break;
>> case VIRTIO_MSI_QUEUE_VECTOR:
>> - vec = vpci->vq_vector[vpci->queue_selector] = ioport__read16(data);
>> + vec = ioport__read16(data);
>> + vpci->vq_vector[vpci->queue_selector] = vec;
>>
>> if (vec == VIRTIO_MSI_NO_VECTOR)
>> break;
>>
>> - gsi = irq__add_msix_route(kvm, &vpci->msix_table[vec].msg);
>> + gsi = irq__add_msix_route(kvm,
>> + &vpci->msix_table[vec].msg);
>> + if (gsi < 0)
>> + break;
>> vpci->gsis[vpci->queue_selector] = gsi;
>> if (vdev->ops->notify_vq_gsi)
>> vdev->ops->notify_vq_gsi(kvm, vpci->dev,
>> - vpci->queue_selector, gsi);
>> + vpci->queue_selector,
>> + gsi);
>> break;
>> };
>>
>> diff --git a/x86/irq.c b/x86/irq.c
>> index 72177e7..db465a1 100644
>> --- a/x86/irq.c
>> +++ b/x86/irq.c
>> @@ -11,20 +11,15 @@
>> #include <stddef.h>
>> #include <stdlib.h>
>>
>> -#define IRQ_MAX_GSI 64
>> #define IRQCHIP_MASTER 0
>> #define IRQCHIP_SLAVE 1
>> #define IRQCHIP_IOAPIC 2
>>
>> -/* First 24 GSIs are routed between IRQCHIPs and IOAPICs */
>> -static u32 gsi = 24;
>> -
>> -struct kvm_irq_routing *irq_routing;
>> -
>> static int irq__add_routing(u32 gsi, u32 type, u32 irqchip, u32 pin)
>> {
>> - if (gsi >= IRQ_MAX_GSI)
>> - return -ENOSPC;
>> + int r = irq__allocate_routing_entry();
>> + if (r)
>> + return r;
>>
>> irq_routing->entries[irq_routing->nr++] =
>> (struct kvm_irq_routing_entry) {
>> @@ -41,11 +36,6 @@ int irq__init(struct kvm *kvm)
>> {
>> int i, r;
>>
>> - irq_routing = calloc(sizeof(struct kvm_irq_routing) +
>> - IRQ_MAX_GSI * sizeof(struct kvm_irq_routing_entry), 1);
>> - if (irq_routing == NULL)
>> - return -ENOMEM;
>> -
>> /* Hook first 8 GSIs to master IRQCHIP */
>> for (i = 0; i < 8; i++)
>> if (i != 2)
>> @@ -69,33 +59,8 @@ int irq__init(struct kvm *kvm)
>> return errno;
>> }
>>
>> - return 0;
>> -}
>> -dev_base_init(irq__init);
>> + next_gsi = i;
>>
>> -int irq__exit(struct kvm *kvm)
>> -{
>> - free(irq_routing);
>> return 0;
>> }
>> -dev_base_exit(irq__exit);
>> -
>> -int irq__add_msix_route(struct kvm *kvm, struct msi_msg *msg)
>> -{
>> - int r;
>> -
>> - irq_routing->entries[irq_routing->nr++] =
>> - (struct kvm_irq_routing_entry) {
>> - .gsi = gsi,
>> - .type = KVM_IRQ_ROUTING_MSI,
>> - .u.msi.address_hi = msg->address_hi,
>> - .u.msi.address_lo = msg->address_lo,
>> - .u.msi.data = msg->data,
>> - };
>> -
>> - r = ioctl(kvm->vm_fd, KVM_SET_GSI_ROUTING, irq_routing);
>> - if (r)
>> - return r;
>> -
>> - return gsi++;
>> -}
>> +dev_base_init(irq__init);
>>
>
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