[PATCH v14 20/20] vfio/platform: implement IRQ masking/unmasking via an eventfd

Baptiste Reynal
2015-03-02T17:03:45Z

With this patch the VFIO user will be able to set an eventfd that can be
used in order to mask and unmask IRQs of platform devices.

Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
---
drivers/vfio/platform/vfio_platform_irq.c | 47 ++++++++++++++++++++++++---
drivers/vfio/platform/vfio_platform_private.h | 2 ++
2 files changed, 45 insertions(+), 4 deletions(-)

diff --git a/drivers/vfio/platform/vfio_platform_irq.c b/drivers/vfio/platform/vfio_platform_irq.c
index e0e6388..88bba57 100644
--- a/drivers/vfio/platform/vfio_platform_irq.c
+++ b/drivers/vfio/platform/vfio_platform_irq.c
@@ -37,6 +37,15 @@ static void vfio_platform_mask(struct vfio_platform_irq *irq_ctx)
spin_unlock_irqrestore(&irq_ctx->lock, flags);
}

+static int vfio_platform_mask_handler(void *opaque, void *unused)
+{
+ struct vfio_platform_irq *irq_ctx = opaque;
+
+ vfio_platform_mask(irq_ctx);
+
+ return 0;
+}
+
static int vfio_platform_set_irq_mask(struct vfio_platform_device *vdev,
unsigned index, unsigned start,
unsigned count, uint32_t flags,
@@ -48,8 +57,18 @@ static int vfio_platform_set_irq_mask(struct vfio_platform_device *vdev,
if (!(vdev->irqs[index].flags & VFIO_IRQ_INFO_MASKABLE))
return -EINVAL;

- if (flags & VFIO_IRQ_SET_DATA_EVENTFD)
- return -EINVAL; /* not implemented yet */
+ if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
+ int32_t fd = *(int32_t *)data;
+
+ if (fd >= 0)
+ return vfio_virqfd_enable((void *) &vdev->irqs[index],
+ vfio_platform_mask_handler,
+ NULL, NULL,
+ &vdev->irqs[index].mask, fd);
+
+ vfio_virqfd_disable(&vdev->irqs[index].mask);
+ return 0;
+ }

if (flags & VFIO_IRQ_SET_DATA_NONE) {
vfio_platform_mask(&vdev->irqs[index]);
@@ -78,6 +97,15 @@ static void vfio_platform_unmask(struct vfio_platform_irq *irq_ctx)
spin_unlock_irqrestore(&irq_ctx->lock, flags);
}

+static int vfio_platform_unmask_handler(void *opaque, void *unused)
+{
+ struct vfio_platform_irq *irq_ctx = opaque;
+
+ vfio_platform_unmask(irq_ctx);
+
+ return 0;
+}
+
static int vfio_platform_set_irq_unmask(struct vfio_platform_device *vdev,
unsigned index, unsigned start,
unsigned count, uint32_t flags,
@@ -89,8 +117,19 @@ static int vfio_platform_set_irq_unmask(struct vfio_platform_device *vdev,
if (!(vdev->irqs[index].flags & VFIO_IRQ_INFO_MASKABLE))
return -EINVAL;

- if (flags & VFIO_IRQ_SET_DATA_EVENTFD)
- return -EINVAL; /* not implemented yet */
+ if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
+ int32_t fd = *(int32_t *)data;
+
+ if (fd >= 0)
+ return vfio_virqfd_enable((void *) &vdev->irqs[index],
+ vfio_platform_unmask_handler,
+ NULL, NULL,
+ &vdev->irqs[index].unmask,
+ fd);
+
+ vfio_virqfd_disable(&vdev->irqs[index].unmask);
+ return 0;
+ }

if (flags & VFIO_IRQ_SET_DATA_NONE) {
vfio_platform_unmask(&vdev->irqs[index]);
diff --git a/drivers/vfio/platform/vfio_platform_private.h b/drivers/vfio/platform/vfio_platform_private.h
index ff2db1d..5d31e04 100644
--- a/drivers/vfio/platform/vfio_platform_private.h
+++ b/drivers/vfio/platform/vfio_platform_private.h
@@ -35,6 +35,8 @@ struct vfio_platform_irq {
struct eventfd_ctx *trigger;
bool masked;
spinlock_t lock;
+ struct virqfd *unmask;
+ struct virqfd *mask;
};

struct vfio_platform_region {
--
2.3.1