diff mbox

[PATCHv7,20/26] vfio/platform: trigger an interrupt via eventfd

Message ID 1411483586-29304-21-git-send-email-a.motakis@virtualopensystems.com (mailing list archive)
State New, archived
Headers show

Commit Message

Antonios Motakis Sept. 23, 2014, 2:46 p.m. UTC 
This patch allows to set an eventfd for a patform device's interrupt,
and also to trigger the interrupt eventfd from userspace for testing.

Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
---
 drivers/vfio/platform/vfio_platform_irq.c     | 89 ++++++++++++++++++++++++++-
 drivers/vfio/platform/vfio_platform_private.h |  2 +
 2 files changed, 89 insertions(+), 2 deletions(-)

Comments

Alex Williamson Sept. 24, 2014, 5 p.m. UTC | #1 
On Tue, 2014-09-23 at 16:46 +0200, Antonios Motakis wrote:
> This patch allows to set an eventfd for a patform device's interrupt,
> and also to trigger the interrupt eventfd from userspace for testing.
> 
> Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
> ---
>  drivers/vfio/platform/vfio_platform_irq.c     | 89 ++++++++++++++++++++++++++-
>  drivers/vfio/platform/vfio_platform_private.h |  2 +
>  2 files changed, 89 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/vfio/platform/vfio_platform_irq.c b/drivers/vfio/platform/vfio_platform_irq.c
> index 007b386..25a7825 100644
> --- a/drivers/vfio/platform/vfio_platform_irq.c
> +++ b/drivers/vfio/platform/vfio_platform_irq.c
> @@ -45,11 +45,91 @@ static int vfio_platform_set_irq_unmask(struct vfio_platform_device *vdev,
>  	return -EINVAL;
>  }
>  
> +static irqreturn_t vfio_irq_handler(int irq, void *dev_id)
> +{
> +	struct vfio_platform_irq *irq_ctx = dev_id;
> +
> +	eventfd_signal(irq_ctx->trigger, 1);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static int vfio_set_trigger(struct vfio_platform_device *vdev,
> +			    int index, int fd)
> +{
> +	struct vfio_platform_irq *irq = &vdev->irqs[index];
> +	struct eventfd_ctx *trigger;
> +	int ret;
> +
> +	if (irq->trigger) {
> +		free_irq(irq->hwirq, irq);
> +		kfree(irq->name);
> +		eventfd_ctx_put(irq->trigger);
> +		irq->trigger = NULL;
> +	}
> +
> +	if (fd < 0) /* Disable only */
> +		return 0;
> +
> +	irq->name = kasprintf(GFP_KERNEL, "vfio-irq[%d](%s)",
> +						irq->hwirq, vdev->name);
> +	if (!irq->name)
> +		return -ENOMEM;
> +
> +	trigger = eventfd_ctx_fdget(fd);
> +	if (IS_ERR(trigger)) {
> +		kfree(irq->name);
> +		return PTR_ERR(trigger);
> +	}
> +
> +	irq->trigger = trigger;
> +
> +	ret = request_irq(irq->hwirq, vfio_irq_handler, 0, irq->name, irq);
> +	if (ret) {
> +		kfree(irq->name);
> +		eventfd_ctx_put(trigger);
> +		irq->trigger = NULL;
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
>  static int vfio_platform_set_irq_trigger(struct vfio_platform_device *vdev,
>  				     unsigned index, unsigned start,
>  				     unsigned count, uint32_t flags, void *data)
>  {
> -	return -EINVAL;
> +	struct vfio_platform_irq *irq = &vdev->irqs[index];
> +	uint8_t irq_bitmap;

Minor nit here and also present in the next patch, I believe when we
have DATA_BOOL, it's defined to be a u8 array, where each byte is a
bool, not each bit.  So it's not actually a bitmap.  The PCI code
handles any non-zero byte as true, not just bit0.  Thanks,

Alex

> +	int32_t fd;
> +
> +	switch (flags & VFIO_IRQ_SET_DATA_TYPE_MASK) {
> +	case VFIO_IRQ_SET_DATA_NONE:
> +		if (count == 0)
> +			return vfio_set_trigger(vdev, index, -1);
> +
> +		vfio_irq_handler(irq->hwirq, irq);
> +		return 0;
> +
> +	case VFIO_IRQ_SET_DATA_BOOL:
> +		if (copy_from_user(&irq_bitmap, data, sizeof(uint8_t)))
> +			return -EFAULT;
> +
> +		if (irq_bitmap == 0x1) {
> +			vfio_irq_handler(irq->hwirq, irq);
> +			return 0;
> +		}
> +
> +		return -EINVAL;
> +
> +	case VFIO_IRQ_SET_DATA_EVENTFD:
> +		if (copy_from_user(&fd, data, sizeof(int32_t)))
> +			return -EFAULT;
> +
> +		return vfio_set_trigger(vdev, index, fd);
> +	}
> +
> +	return -EFAULT;
>  }
>  
>  int vfio_platform_set_irqs_ioctl(struct vfio_platform_device *vdev,
> @@ -95,7 +175,7 @@ int vfio_platform_irq_init(struct vfio_platform_device *vdev)
>  		if (hwirq < 0)
>  			goto err;
>  
> -		vdev->irqs[i].flags = 0;
> +		vdev->irqs[i].flags = VFIO_IRQ_INFO_EVENTFD;
>  		vdev->irqs[i].count = 1;
>  		vdev->irqs[i].hwirq = hwirq;
>  	}
> @@ -110,6 +190,11 @@ err:
>  
>  void vfio_platform_irq_cleanup(struct vfio_platform_device *vdev)
>  {
> +	int i;
> +
> +	for (i = 0; i < vdev->num_irqs; i++)
> +		vfio_set_trigger(vdev, i, -1);
> +
>  	vdev->num_irqs = 0;
>  	kfree(vdev->irqs);
>  }
> diff --git a/drivers/vfio/platform/vfio_platform_private.h b/drivers/vfio/platform/vfio_platform_private.h
> index 4201b94..765b371 100644
> --- a/drivers/vfio/platform/vfio_platform_private.h
> +++ b/drivers/vfio/platform/vfio_platform_private.h
> @@ -28,6 +28,8 @@ struct vfio_platform_irq {
>  	u32			flags;
>  	u32			count;
>  	int			hwirq;
> +	char			*name;
> +	struct eventfd_ctx	*trigger;
>  };
>  
>  struct vfio_platform_region {



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Antonios Motakis Sept. 26, 2014, 3:03 p.m. UTC | #2 
On Wed, Sep 24, 2014 at 7:00 PM, Alex Williamson
<alex.williamson@redhat.com> wrote:
> On Tue, 2014-09-23 at 16:46 +0200, Antonios Motakis wrote:
>> This patch allows to set an eventfd for a patform device's interrupt,
>> and also to trigger the interrupt eventfd from userspace for testing.
>>
>> Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
>> ---
>>  drivers/vfio/platform/vfio_platform_irq.c     | 89 ++++++++++++++++++++++++++-
>>  drivers/vfio/platform/vfio_platform_private.h |  2 +
>>  2 files changed, 89 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/vfio/platform/vfio_platform_irq.c b/drivers/vfio/platform/vfio_platform_irq.c
>> index 007b386..25a7825 100644
>> --- a/drivers/vfio/platform/vfio_platform_irq.c
>> +++ b/drivers/vfio/platform/vfio_platform_irq.c
>> @@ -45,11 +45,91 @@ static int vfio_platform_set_irq_unmask(struct vfio_platform_device *vdev,
>>       return -EINVAL;
>>  }
>>
>> +static irqreturn_t vfio_irq_handler(int irq, void *dev_id)
>> +{
>> +     struct vfio_platform_irq *irq_ctx = dev_id;
>> +
>> +     eventfd_signal(irq_ctx->trigger, 1);
>> +
>> +     return IRQ_HANDLED;
>> +}
>> +
>> +static int vfio_set_trigger(struct vfio_platform_device *vdev,
>> +                         int index, int fd)
>> +{
>> +     struct vfio_platform_irq *irq = &vdev->irqs[index];
>> +     struct eventfd_ctx *trigger;
>> +     int ret;
>> +
>> +     if (irq->trigger) {
>> +             free_irq(irq->hwirq, irq);
>> +             kfree(irq->name);
>> +             eventfd_ctx_put(irq->trigger);
>> +             irq->trigger = NULL;
>> +     }
>> +
>> +     if (fd < 0) /* Disable only */
>> +             return 0;
>> +
>> +     irq->name = kasprintf(GFP_KERNEL, "vfio-irq[%d](%s)",
>> +                                             irq->hwirq, vdev->name);
>> +     if (!irq->name)
>> +             return -ENOMEM;
>> +
>> +     trigger = eventfd_ctx_fdget(fd);
>> +     if (IS_ERR(trigger)) {
>> +             kfree(irq->name);
>> +             return PTR_ERR(trigger);
>> +     }
>> +
>> +     irq->trigger = trigger;
>> +
>> +     ret = request_irq(irq->hwirq, vfio_irq_handler, 0, irq->name, irq);
>> +     if (ret) {
>> +             kfree(irq->name);
>> +             eventfd_ctx_put(trigger);
>> +             irq->trigger = NULL;
>> +             return ret;
>> +     }
>> +
>> +     return 0;
>> +}
>> +
>>  static int vfio_platform_set_irq_trigger(struct vfio_platform_device *vdev,
>>                                    unsigned index, unsigned start,
>>                                    unsigned count, uint32_t flags, void *data)
>>  {
>> -     return -EINVAL;
>> +     struct vfio_platform_irq *irq = &vdev->irqs[index];
>> +     uint8_t irq_bitmap;
>
> Minor nit here and also present in the next patch, I believe when we
> have DATA_BOOL, it's defined to be a u8 array, where each byte is a
> bool, not each bit.  So it's not actually a bitmap.  The PCI code
> handles any non-zero byte as true, not just bit0.  Thanks,
>

Ok, I will correct this. Thanks for the clarification.

> Alex
>
>> +     int32_t fd;
>> +
>> +     switch (flags & VFIO_IRQ_SET_DATA_TYPE_MASK) {
>> +     case VFIO_IRQ_SET_DATA_NONE:
>> +             if (count == 0)
>> +                     return vfio_set_trigger(vdev, index, -1);
>> +
>> +             vfio_irq_handler(irq->hwirq, irq);
>> +             return 0;
>> +
>> +     case VFIO_IRQ_SET_DATA_BOOL:
>> +             if (copy_from_user(&irq_bitmap, data, sizeof(uint8_t)))
>> +                     return -EFAULT;
>> +
>> +             if (irq_bitmap == 0x1) {
>> +                     vfio_irq_handler(irq->hwirq, irq);
>> +                     return 0;
>> +             }
>> +
>> +             return -EINVAL;
>> +
>> +     case VFIO_IRQ_SET_DATA_EVENTFD:
>> +             if (copy_from_user(&fd, data, sizeof(int32_t)))
>> +                     return -EFAULT;
>> +
>> +             return vfio_set_trigger(vdev, index, fd);
>> +     }
>> +
>> +     return -EFAULT;
>>  }
>>
>>  int vfio_platform_set_irqs_ioctl(struct vfio_platform_device *vdev,
>> @@ -95,7 +175,7 @@ int vfio_platform_irq_init(struct vfio_platform_device *vdev)
>>               if (hwirq < 0)
>>                       goto err;
>>
>> -             vdev->irqs[i].flags = 0;
>> +             vdev->irqs[i].flags = VFIO_IRQ_INFO_EVENTFD;
>>               vdev->irqs[i].count = 1;
>>               vdev->irqs[i].hwirq = hwirq;
>>       }
>> @@ -110,6 +190,11 @@ err:
>>
>>  void vfio_platform_irq_cleanup(struct vfio_platform_device *vdev)
>>  {
>> +     int i;
>> +
>> +     for (i = 0; i < vdev->num_irqs; i++)
>> +             vfio_set_trigger(vdev, i, -1);
>> +
>>       vdev->num_irqs = 0;
>>       kfree(vdev->irqs);
>>  }
>> diff --git a/drivers/vfio/platform/vfio_platform_private.h b/drivers/vfio/platform/vfio_platform_private.h
>> index 4201b94..765b371 100644
>> --- a/drivers/vfio/platform/vfio_platform_private.h
>> +++ b/drivers/vfio/platform/vfio_platform_private.h
>> @@ -28,6 +28,8 @@ struct vfio_platform_irq {
>>       u32                     flags;
>>       u32                     count;
>>       int                     hwirq;
>> +     char                    *name;
>> +     struct eventfd_ctx      *trigger;
>>  };
>>
>>  struct vfio_platform_region {
>
>
>
diff mbox

Patch

diff --git a/drivers/vfio/platform/vfio_platform_irq.c b/drivers/vfio/platform/vfio_platform_irq.c
index 007b386..25a7825 100644
--- a/drivers/vfio/platform/vfio_platform_irq.c
+++ b/drivers/vfio/platform/vfio_platform_irq.c
@@ -45,11 +45,91 @@  static int vfio_platform_set_irq_unmask(struct vfio_platform_device *vdev,
 	return -EINVAL;
 }
 
+static irqreturn_t vfio_irq_handler(int irq, void *dev_id)
+{
+	struct vfio_platform_irq *irq_ctx = dev_id;
+
+	eventfd_signal(irq_ctx->trigger, 1);
+
+	return IRQ_HANDLED;
+}
+
+static int vfio_set_trigger(struct vfio_platform_device *vdev,
+			    int index, int fd)
+{
+	struct vfio_platform_irq *irq = &vdev->irqs[index];
+	struct eventfd_ctx *trigger;
+	int ret;
+
+	if (irq->trigger) {
+		free_irq(irq->hwirq, irq);
+		kfree(irq->name);
+		eventfd_ctx_put(irq->trigger);
+		irq->trigger = NULL;
+	}
+
+	if (fd < 0) /* Disable only */
+		return 0;
+
+	irq->name = kasprintf(GFP_KERNEL, "vfio-irq[%d](%s)",
+						irq->hwirq, vdev->name);
+	if (!irq->name)
+		return -ENOMEM;
+
+	trigger = eventfd_ctx_fdget(fd);
+	if (IS_ERR(trigger)) {
+		kfree(irq->name);
+		return PTR_ERR(trigger);
+	}
+
+	irq->trigger = trigger;
+
+	ret = request_irq(irq->hwirq, vfio_irq_handler, 0, irq->name, irq);
+	if (ret) {
+		kfree(irq->name);
+		eventfd_ctx_put(trigger);
+		irq->trigger = NULL;
+		return ret;
+	}
+
+	return 0;
+}
+
 static int vfio_platform_set_irq_trigger(struct vfio_platform_device *vdev,
 				     unsigned index, unsigned start,
 				     unsigned count, uint32_t flags, void *data)
 {
-	return -EINVAL;
+	struct vfio_platform_irq *irq = &vdev->irqs[index];
+	uint8_t irq_bitmap;
+	int32_t fd;
+
+	switch (flags & VFIO_IRQ_SET_DATA_TYPE_MASK) {
+	case VFIO_IRQ_SET_DATA_NONE:
+		if (count == 0)
+			return vfio_set_trigger(vdev, index, -1);
+
+		vfio_irq_handler(irq->hwirq, irq);
+		return 0;
+
+	case VFIO_IRQ_SET_DATA_BOOL:
+		if (copy_from_user(&irq_bitmap, data, sizeof(uint8_t)))
+			return -EFAULT;
+
+		if (irq_bitmap == 0x1) {
+			vfio_irq_handler(irq->hwirq, irq);
+			return 0;
+		}
+
+		return -EINVAL;
+
+	case VFIO_IRQ_SET_DATA_EVENTFD:
+		if (copy_from_user(&fd, data, sizeof(int32_t)))
+			return -EFAULT;
+
+		return vfio_set_trigger(vdev, index, fd);
+	}
+
+	return -EFAULT;
 }
 
 int vfio_platform_set_irqs_ioctl(struct vfio_platform_device *vdev,
@@ -95,7 +175,7 @@  int vfio_platform_irq_init(struct vfio_platform_device *vdev)
 		if (hwirq < 0)
 			goto err;
 
-		vdev->irqs[i].flags = 0;
+		vdev->irqs[i].flags = VFIO_IRQ_INFO_EVENTFD;
 		vdev->irqs[i].count = 1;
 		vdev->irqs[i].hwirq = hwirq;
 	}
@@ -110,6 +190,11 @@  err:
 
 void vfio_platform_irq_cleanup(struct vfio_platform_device *vdev)
 {
+	int i;
+
+	for (i = 0; i < vdev->num_irqs; i++)
+		vfio_set_trigger(vdev, i, -1);
+
 	vdev->num_irqs = 0;
 	kfree(vdev->irqs);
 }
diff --git a/drivers/vfio/platform/vfio_platform_private.h b/drivers/vfio/platform/vfio_platform_private.h
index 4201b94..765b371 100644
--- a/drivers/vfio/platform/vfio_platform_private.h
+++ b/drivers/vfio/platform/vfio_platform_private.h
@@ -28,6 +28,8 @@  struct vfio_platform_irq {
 	u32			flags;
 	u32			count;
 	int			hwirq;
+	char			*name;
+	struct eventfd_ctx	*trigger;
 };
 
 struct vfio_platform_region {