[PATCH v7 12/18] virt: acrn: Introduce interrupt injection interfaces

From: shuo . a . liu
Date: Wed Jan 06 2021 - 02:53:40 EST


From: Shuo Liu <shuo.a.liu@xxxxxxxxx>

ACRN userspace need to inject virtual interrupts into a User VM in
devices emulation.

HSM needs provide interfaces to do so.

Introduce following interrupt injection interfaces:

ioctl ACRN_IOCTL_SET_IRQLINE:
Pass data from userspace to the hypervisor, and inform the hypervisor
to inject a virtual IOAPIC GSI interrupt to a User VM.

ioctl ACRN_IOCTL_INJECT_MSI:
Pass data struct acrn_msi_entry from userspace to the hypervisor, and
inform the hypervisor to inject a virtual MSI to a User VM.

ioctl ACRN_IOCTL_VM_INTR_MONITOR:
Set a 4-Kbyte aligned shared page for statistics information of
interrupts of a User VM.

Signed-off-by: Shuo Liu <shuo.a.liu@xxxxxxxxx>
Reviewed-by: Zhi Wang <zhi.a.wang@xxxxxxxxx>
Reviewed-by: Reinette Chatre <reinette.chatre@xxxxxxxxx>
Cc: Zhi Wang <zhi.a.wang@xxxxxxxxx>
Cc: Zhenyu Wang <zhenyuw@xxxxxxxxxxxxxxx>
Cc: Yu Wang <yu1.wang@xxxxxxxxx>
Cc: Reinette Chatre <reinette.chatre@xxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/virt/acrn/acrn_drv.h | 4 ++++
drivers/virt/acrn/hsm.c | 40 ++++++++++++++++++++++++++++++++++
drivers/virt/acrn/hypercall.h | 41 +++++++++++++++++++++++++++++++++++
drivers/virt/acrn/vm.c | 36 ++++++++++++++++++++++++++++++
include/uapi/linux/acrn.h | 17 +++++++++++++++
5 files changed, 138 insertions(+)

diff --git a/drivers/virt/acrn/acrn_drv.h b/drivers/virt/acrn/acrn_drv.h
index 97a7f31cd681..542448c88026 100644
--- a/drivers/virt/acrn/acrn_drv.h
+++ b/drivers/virt/acrn/acrn_drv.h
@@ -155,6 +155,7 @@ extern rwlock_t acrn_vm_list_lock;
* @ioreq_buf: I/O request shared buffer
* @ioreq_page: The page of the I/O request shared buffer
* @pci_conf_addr: Address of a PCI configuration access emulation
+ * @monitor_page: Page of interrupt statistics of User VM
*/
struct acrn_vm {
struct list_head list;
@@ -170,6 +171,7 @@ struct acrn_vm {
struct acrn_io_request_buffer *ioreq_buf;
struct page *ioreq_page;
u32 pci_conf_addr;
+ struct page *monitor_page;
};

struct acrn_vm *acrn_vm_create(struct acrn_vm *vm,
@@ -196,4 +198,6 @@ struct acrn_ioreq_client *acrn_ioreq_client_create(struct acrn_vm *vm,
const char *name);
void acrn_ioreq_client_destroy(struct acrn_ioreq_client *client);

+int acrn_msi_inject(struct acrn_vm *vm, u64 msi_addr, u64 msi_data);
+
#endif /* __ACRN_HSM_DRV_H */
diff --git a/drivers/virt/acrn/hsm.c b/drivers/virt/acrn/hsm.c
index e5676d0ecbbc..761b99722ab6 100644
--- a/drivers/virt/acrn/hsm.c
+++ b/drivers/virt/acrn/hsm.c
@@ -51,7 +51,9 @@ static long acrn_dev_ioctl(struct file *filp, unsigned int cmd,
struct acrn_ioreq_notify notify;
struct acrn_ptdev_irq *irq_info;
struct acrn_vm_memmap memmap;
+ struct acrn_msi_entry *msi;
struct acrn_pcidev *pcidev;
+ struct page *page;
int i, ret = 0;

if (vm->vmid == ACRN_INVALID_VMID && cmd != ACRN_IOCTL_CREATE_VM) {
@@ -185,6 +187,44 @@ static long acrn_dev_ioctl(struct file *filp, unsigned int cmd,
"Failed to reset intr for ptdev!\n");
kfree(irq_info);
break;
+ case ACRN_IOCTL_SET_IRQLINE:
+ ret = hcall_set_irqline(vm->vmid, ioctl_param);
+ if (ret < 0)
+ dev_dbg(acrn_dev.this_device,
+ "Failed to set interrupt line!\n");
+ break;
+ case ACRN_IOCTL_INJECT_MSI:
+ msi = memdup_user((void __user *)ioctl_param,
+ sizeof(struct acrn_msi_entry));
+ if (IS_ERR(msi))
+ return PTR_ERR(msi);
+
+ ret = hcall_inject_msi(vm->vmid, virt_to_phys(msi));
+ if (ret < 0)
+ dev_dbg(acrn_dev.this_device,
+ "Failed to inject MSI!\n");
+ kfree(msi);
+ break;
+ case ACRN_IOCTL_VM_INTR_MONITOR:
+ ret = pin_user_pages_fast(ioctl_param, 1,
+ FOLL_WRITE | FOLL_LONGTERM, &page);
+ if (unlikely(ret != 1)) {
+ dev_dbg(acrn_dev.this_device,
+ "Failed to pin intr hdr buffer!\n");
+ return -EFAULT;
+ }
+
+ ret = hcall_vm_intr_monitor(vm->vmid, page_to_phys(page));
+ if (ret < 0) {
+ unpin_user_page(page);
+ dev_dbg(acrn_dev.this_device,
+ "Failed to monitor intr data!\n");
+ return ret;
+ }
+ if (vm->monitor_page)
+ unpin_user_page(vm->monitor_page);
+ vm->monitor_page = page;
+ break;
case ACRN_IOCTL_CREATE_IOREQ_CLIENT:
if (vm->default_client)
return -EEXIST;
diff --git a/drivers/virt/acrn/hypercall.h b/drivers/virt/acrn/hypercall.h
index f448301832cf..a8813397a3fe 100644
--- a/drivers/virt/acrn/hypercall.h
+++ b/drivers/virt/acrn/hypercall.h
@@ -21,6 +21,11 @@
#define HC_RESET_VM _HC_ID(HC_ID, HC_ID_VM_BASE + 0x05)
#define HC_SET_VCPU_REGS _HC_ID(HC_ID, HC_ID_VM_BASE + 0x06)

+#define HC_ID_IRQ_BASE 0x20UL
+#define HC_INJECT_MSI _HC_ID(HC_ID, HC_ID_IRQ_BASE + 0x03)
+#define HC_VM_INTR_MONITOR _HC_ID(HC_ID, HC_ID_IRQ_BASE + 0x04)
+#define HC_SET_IRQLINE _HC_ID(HC_ID, HC_ID_IRQ_BASE + 0x05)
+
#define HC_ID_IOREQ_BASE 0x30UL
#define HC_SET_IOREQ_BUFFER _HC_ID(HC_ID, HC_ID_IOREQ_BASE + 0x00)
#define HC_NOTIFY_REQUEST_FINISH _HC_ID(HC_ID, HC_ID_IOREQ_BASE + 0x01)
@@ -101,6 +106,42 @@ static inline long hcall_set_vcpu_regs(u64 vmid, u64 regs_state)
return acrn_hypercall2(HC_SET_VCPU_REGS, vmid, regs_state);
}

+/**
+ * hcall_inject_msi() - Deliver a MSI interrupt to a User VM
+ * @vmid: User VM ID
+ * @msi: Service VM GPA of MSI message
+ *
+ * Return: 0 on success, <0 on failure
+ */
+static inline long hcall_inject_msi(u64 vmid, u64 msi)
+{
+ return acrn_hypercall2(HC_INJECT_MSI, vmid, msi);
+}
+
+/**
+ * hcall_vm_intr_monitor() - Set a shared page for User VM interrupt statistics
+ * @vmid: User VM ID
+ * @addr: Service VM GPA of the shared page
+ *
+ * Return: 0 on success, <0 on failure
+ */
+static inline long hcall_vm_intr_monitor(u64 vmid, u64 addr)
+{
+ return acrn_hypercall2(HC_VM_INTR_MONITOR, vmid, addr);
+}
+
+/**
+ * hcall_set_irqline() - Set or clear an interrupt line
+ * @vmid: User VM ID
+ * @op: Service VM GPA of interrupt line operations
+ *
+ * Return: 0 on success, <0 on failure
+ */
+static inline long hcall_set_irqline(u64 vmid, u64 op)
+{
+ return acrn_hypercall2(HC_SET_IRQLINE, vmid, op);
+}
+
/**
* hcall_set_ioreq_buffer() - Set up the shared buffer for I/O Requests.
* @vmid: User VM ID
diff --git a/drivers/virt/acrn/vm.c b/drivers/virt/acrn/vm.c
index 4ee1a99df4b7..38304aeef181 100644
--- a/drivers/virt/acrn/vm.c
+++ b/drivers/virt/acrn/vm.c
@@ -68,6 +68,10 @@ int acrn_vm_destroy(struct acrn_vm *vm)
write_unlock_bh(&acrn_vm_list_lock);

acrn_ioreq_deinit(vm);
+ if (vm->monitor_page) {
+ put_page(vm->monitor_page);
+ vm->monitor_page = NULL;
+ }

ret = hcall_destroy_vm(vm->vmid);
if (ret < 0) {
@@ -83,3 +87,35 @@ int acrn_vm_destroy(struct acrn_vm *vm)
vm->vmid = ACRN_INVALID_VMID;
return 0;
}
+
+/**
+ * acrn_inject_msi() - Inject a MSI interrupt into a User VM
+ * @vm: User VM
+ * @msi_addr: The MSI address
+ * @msi_data: The MSI data
+ *
+ * Return: 0 on success, <0 on error
+ */
+int acrn_msi_inject(struct acrn_vm *vm, u64 msi_addr, u64 msi_data)
+{
+ struct acrn_msi_entry *msi;
+ int ret;
+
+ /* might be used in interrupt context, so use GFP_ATOMIC */
+ msi = kzalloc(sizeof(*msi), GFP_ATOMIC);
+ if (!msi)
+ return -ENOMEM;
+
+ /*
+ * msi_addr: addr[19:12] with dest vcpu id
+ * msi_data: data[7:0] with vector
+ */
+ msi->msi_addr = msi_addr;
+ msi->msi_data = msi_data;
+ ret = hcall_inject_msi(vm->vmid, virt_to_phys(msi));
+ if (ret < 0)
+ dev_err(acrn_dev.this_device,
+ "Failed to inject MSI to VM %u!\n", vm->vmid);
+ kfree(msi);
+ return ret;
+}
diff --git a/include/uapi/linux/acrn.h b/include/uapi/linux/acrn.h
index 2727f16a7ef4..959dfbccc6a4 100644
--- a/include/uapi/linux/acrn.h
+++ b/include/uapi/linux/acrn.h
@@ -336,6 +336,16 @@ struct acrn_pcidev {
__u32 bar[ACRN_PCI_NUM_BARS];
};

+/**
+ * struct acrn_msi_entry - Info for injecting a MSI interrupt to a VM
+ * @msi_addr: MSI addr[19:12] with dest vCPU ID
+ * @msi_data: MSI data[7:0] with vector
+ */
+struct acrn_msi_entry {
+ __u64 msi_addr;
+ __u64 msi_data;
+};
+
/* The ioctl type, documented in ioctl-number.rst */
#define ACRN_IOCTL_TYPE 0xA2

@@ -355,6 +365,13 @@ struct acrn_pcidev {
#define ACRN_IOCTL_SET_VCPU_REGS \
_IOW(ACRN_IOCTL_TYPE, 0x16, struct acrn_vcpu_regs)

+#define ACRN_IOCTL_INJECT_MSI \
+ _IOW(ACRN_IOCTL_TYPE, 0x23, struct acrn_msi_entry)
+#define ACRN_IOCTL_VM_INTR_MONITOR \
+ _IOW(ACRN_IOCTL_TYPE, 0x24, unsigned long)
+#define ACRN_IOCTL_SET_IRQLINE \
+ _IOW(ACRN_IOCTL_TYPE, 0x25, __u64)
+
#define ACRN_IOCTL_NOTIFY_REQUEST_FINISH \
_IOW(ACRN_IOCTL_TYPE, 0x31, struct acrn_ioreq_notify)
#define ACRN_IOCTL_CREATE_IOREQ_CLIENT \
--
2.28.0