LoongArch: KVM: Add irqfd support

Enable the KVM_IRQ_ROUTING/KVM_IRQCHIP/KVM_MSI configuration items,
add the KVM_CAP_IRQCHIP capability, and implement the query interface
of the in-kernel irqchip.

Signed-off-by: Xianglai Li <lixianglai@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

diff --git a/arch/loongarch/include/asm/kvm_host.h b/arch/loongarch/include/asm/kvm_host.h
index d1f75b8541074150032439c9f1e449d62205fcc8..7b8367c39da85f2328663d44f6cf82457dca7290 100644 (file)
--- a/arch/loongarch/include/asm/kvm_host.h
+++ b/arch/loongarch/include/asm/kvm_host.h
@@ -23,6 +23,8 @@
 #include <asm/kvm_pch_pic.h>
 #include <asm/loongarch.h>
 
+#define __KVM_HAVE_ARCH_INTC_INITIALIZED
+
 /* Loongarch KVM register ids */
 #define KVM_GET_IOC_CSR_IDX(id)                ((id & KVM_CSR_IDX_MASK) >> LOONGARCH_REG_SHIFT)
 #define KVM_GET_IOC_CPUCFG_IDX(id)     ((id & KVM_CPUCFG_IDX_MASK) >> LOONGARCH_REG_SHIFT)

diff --git a/arch/loongarch/include/uapi/asm/kvm.h b/arch/loongarch/include/uapi/asm/kvm.h
index 72af0e854a50acbf72400e1e6d20c3135d78c302..5f354f5c684701c353a1bfe2eb213025aa834a1c 100644 (file)
--- a/arch/loongarch/include/uapi/asm/kvm.h
+++ b/arch/loongarch/include/uapi/asm/kvm.h
@@ -8,6 +8,8 @@
 
 #include <linux/types.h>
 
+#define __KVM_HAVE_IRQ_LINE
+
 /*
  * KVM LoongArch specific structures and definitions.
  *

diff --git a/arch/loongarch/kvm/Kconfig b/arch/loongarch/kvm/Kconfig
index 248744b4d086d10049511cb9990b0a1e4aca26d3..97a811077ac3afd6cd3ead400146c05ebde97a1d 100644 (file)
--- a/arch/loongarch/kvm/Kconfig
+++ b/arch/loongarch/kvm/Kconfig
@@ -21,13 +21,16 @@ config KVM
        tristate "Kernel-based Virtual Machine (KVM) support"
        depends on AS_HAS_LVZ_EXTENSION
        select HAVE_KVM_DIRTY_RING_ACQ_REL
+       select HAVE_KVM_IRQ_ROUTING
+       select HAVE_KVM_IRQCHIP
+       select HAVE_KVM_MSI
+       select HAVE_KVM_READONLY_MEM
        select HAVE_KVM_VCPU_ASYNC_IOCTL
        select KVM_COMMON
        select KVM_GENERIC_DIRTYLOG_READ_PROTECT
        select KVM_GENERIC_HARDWARE_ENABLING
        select KVM_GENERIC_MMU_NOTIFIER
        select KVM_MMIO
-       select HAVE_KVM_READONLY_MEM
        select KVM_XFER_TO_GUEST_WORK
        select SCHED_INFO
        help

diff --git a/arch/loongarch/kvm/Makefile b/arch/loongarch/kvm/Makefile
index 97b2adf08206a0140fb04bc91ac71fdc4f05ce1f..3a01292f71cc2b29ab019d5e7ac5d56b0bb8d8e3 100644 (file)
--- a/arch/loongarch/kvm/Makefile
+++ b/arch/loongarch/kvm/Makefile
@@ -21,5 +21,6 @@ kvm-y += vm.o
 kvm-y += intc/ipi.o
 kvm-y += intc/eiointc.o
 kvm-y += intc/pch_pic.o
+kvm-y += irqfd.o
 
 CFLAGS_exit.o  += $(call cc-option,-Wno-override-init,)

diff --git a/arch/loongarch/kvm/intc/pch_pic.c b/arch/loongarch/kvm/intc/pch_pic.c
index fe1f966d6c8ad7025e0603d6371ea6a4c439148c..08fce845f66803adb7b4a63e7ffedc1f32202018 100644 (file)
--- a/arch/loongarch/kvm/intc/pch_pic.c
+++ b/arch/loongarch/kvm/intc/pch_pic.c
@@ -443,8 +443,31 @@ static int kvm_pch_pic_set_attr(struct kvm_device *dev,
        }
 }
 
+static int kvm_setup_default_irq_routing(struct kvm *kvm)
+{
+       int i, ret;
+       u32 nr = KVM_IRQCHIP_NUM_PINS;
+       struct kvm_irq_routing_entry *entries;
+
+       entries = kcalloc(nr, sizeof(*entries), GFP_KERNEL);
+       if (!entries)
+               return -ENOMEM;
+
+       for (i = 0; i < nr; i++) {
+               entries[i].gsi = i;
+               entries[i].type = KVM_IRQ_ROUTING_IRQCHIP;
+               entries[i].u.irqchip.irqchip = 0;
+               entries[i].u.irqchip.pin = i;
+       }
+       ret = kvm_set_irq_routing(kvm, entries, nr, 0);
+       kfree(entries);
+
+       return ret;
+}
+
 static int kvm_pch_pic_create(struct kvm_device *dev, u32 type)
 {
+       int ret;
        struct kvm *kvm = dev->kvm;
        struct loongarch_pch_pic *s;
 
@@ -452,6 +475,10 @@ static int kvm_pch_pic_create(struct kvm_device *dev, u32 type)
        if (kvm->arch.pch_pic)
                return -EINVAL;
 
+       ret = kvm_setup_default_irq_routing(kvm);
+       if (ret)
+               return -ENOMEM;
+
        s = kzalloc(sizeof(struct loongarch_pch_pic), GFP_KERNEL);
        if (!s)
                return -ENOMEM;

diff --git a/arch/loongarch/kvm/irqfd.c b/arch/loongarch/kvm/irqfd.c
new file mode 100644 (file)
index 0000000..9a39627
--- /dev/null
+++ b/arch/loongarch/kvm/irqfd.c
@@ -0,0 +1,89 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2024 Loongson Technology Corporation Limited
+ */
+
+#include <linux/kvm_host.h>
+#include <trace/events/kvm.h>
+#include <asm/kvm_pch_pic.h>
+
+static int kvm_set_pic_irq(struct kvm_kernel_irq_routing_entry *e,
+               struct kvm *kvm, int irq_source_id, int level, bool line_status)
+{
+       /* PCH-PIC pin (0 ~ 64) <---> GSI (0 ~ 64) */
+       pch_pic_set_irq(kvm->arch.pch_pic, e->irqchip.pin, level);
+
+       return 0;
+}
+
+/*
+ * kvm_set_msi: inject the MSI corresponding to the
+ * MSI routing entry
+ *
+ * This is the entry point for irqfd MSI injection
+ * and userspace MSI injection.
+ */
+int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
+               struct kvm *kvm, int irq_source_id, int level, bool line_status)
+{
+       if (!level)
+               return -1;
+
+       pch_msi_set_irq(kvm, e->msi.data, level);
+
+       return 0;
+}
+
+/*
+ * kvm_set_routing_entry: populate a kvm routing entry
+ * from a user routing entry
+ *
+ * @kvm: the VM this entry is applied to
+ * @e: kvm kernel routing entry handle
+ * @ue: user api routing entry handle
+ * return 0 on success, -EINVAL on errors.
+ */
+int kvm_set_routing_entry(struct kvm *kvm,
+                       struct kvm_kernel_irq_routing_entry *e,
+                       const struct kvm_irq_routing_entry *ue)
+{
+       switch (ue->type) {
+       case KVM_IRQ_ROUTING_IRQCHIP:
+               e->set = kvm_set_pic_irq;
+               e->irqchip.irqchip = ue->u.irqchip.irqchip;
+               e->irqchip.pin = ue->u.irqchip.pin;
+
+               if (e->irqchip.pin >= KVM_IRQCHIP_NUM_PINS)
+                       return -EINVAL;
+
+               return 0;
+       case KVM_IRQ_ROUTING_MSI:
+               e->set = kvm_set_msi;
+               e->msi.address_lo = ue->u.msi.address_lo;
+               e->msi.address_hi = ue->u.msi.address_hi;
+               e->msi.data = ue->u.msi.data;
+               return 0;
+       default:
+               return -EINVAL;
+       }
+}
+
+int kvm_arch_set_irq_inatomic(struct kvm_kernel_irq_routing_entry *e,
+               struct kvm *kvm, int irq_source_id, int level, bool line_status)
+{
+       switch (e->type) {
+       case KVM_IRQ_ROUTING_IRQCHIP:
+               pch_pic_set_irq(kvm->arch.pch_pic, e->irqchip.pin, level);
+               return 0;
+       case KVM_IRQ_ROUTING_MSI:
+               pch_msi_set_irq(kvm, e->msi.data, level);
+               return 0;
+       default:
+               return -EWOULDBLOCK;
+       }
+}
+
+bool kvm_arch_intc_initialized(struct kvm *kvm)
+{
+       return kvm_arch_irqchip_in_kernel(kvm);
+}

diff --git a/arch/loongarch/kvm/vm.c b/arch/loongarch/kvm/vm.c
index 4ba734aaef87a796da4d97e67dcb3fb680b6cef2..b8b3e1972d6eaa889f84c81e57e562b549f35ba7 100644 (file)
--- a/arch/loongarch/kvm/vm.c
+++ b/arch/loongarch/kvm/vm.c
@@ -6,6 +6,8 @@
 #include <linux/kvm_host.h>
 #include <asm/kvm_mmu.h>
 #include <asm/kvm_vcpu.h>
+#include <asm/kvm_eiointc.h>
+#include <asm/kvm_pch_pic.h>
 
 const struct _kvm_stats_desc kvm_vm_stats_desc[] = {
        KVM_GENERIC_VM_STATS(),
@@ -76,6 +78,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
        int r;
 
        switch (ext) {
+       case KVM_CAP_IRQCHIP:
        case KVM_CAP_ONE_REG:
        case KVM_CAP_ENABLE_CAP:
        case KVM_CAP_READONLY_MEM:
@@ -161,6 +164,8 @@ int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
        struct kvm_device_attr attr;
 
        switch (ioctl) {
+       case KVM_CREATE_IRQCHIP:
+               return 0;
        case KVM_HAS_DEVICE_ATTR:
                if (copy_from_user(&attr, argp, sizeof(attr)))
                        return -EFAULT;
@@ -170,3 +175,19 @@ int kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
                return -ENOIOCTLCMD;
        }
 }
+
+int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_event, bool line_status)
+{
+       if (!kvm_arch_irqchip_in_kernel(kvm))
+               return -ENXIO;
+
+       irq_event->status = kvm_set_irq(kvm, KVM_USERSPACE_IRQ_SOURCE_ID,
+                                       irq_event->irq, irq_event->level, line_status);
+
+       return 0;
+}
+
+bool kvm_arch_irqchip_in_kernel(struct kvm *kvm)
+{
+       return (kvm->arch.ipi && kvm->arch.eiointc && kvm->arch.pch_pic);
+}