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.mota...@virtualopensystems.com> --- drivers/vfio/platform/vfio_platform.c | 36 +++++++- drivers/vfio/platform/vfio_platform_irq.c | 123 +++++++++++++++++++++++++- drivers/vfio/platform/vfio_platform_private.h | 7 ++ 3 files changed, 162 insertions(+), 4 deletions(-) diff --git a/drivers/vfio/platform/vfio_platform.c b/drivers/vfio/platform/vfio_platform.c index 2e16595..8aa5d10 100644 --- a/drivers/vfio/platform/vfio_platform.c +++ b/drivers/vfio/platform/vfio_platform.c @@ -174,10 +174,40 @@ static long vfio_platform_ioctl(void *device_data, return copy_to_user((void __user *)arg, &info, minsz); - } else if (cmd == VFIO_DEVICE_SET_IRQS) - return -EINVAL; + } else if (cmd == VFIO_DEVICE_SET_IRQS) { + struct vfio_irq_set hdr; + int ret = 0; + + minsz = offsetofend(struct vfio_irq_set, count); + + if (copy_from_user(&hdr, (void __user *)arg, minsz)) + return -EFAULT; + + if (hdr.argsz < minsz) + return -EINVAL; + + if (hdr.index >= vdev->num_irqs) + return -EINVAL; + + if (hdr.start != 0 || hdr.count > 1) + return -EINVAL; + + if (hdr.count == 0 && + (!(hdr.flags & VFIO_IRQ_SET_DATA_NONE) || + !(hdr.flags & VFIO_IRQ_SET_ACTION_TRIGGER))) + return -EINVAL; + + if (hdr.flags & ~(VFIO_IRQ_SET_DATA_TYPE_MASK | + VFIO_IRQ_SET_ACTION_TYPE_MASK)) + return -EINVAL; + + ret = vfio_platform_set_irqs_ioctl(vdev, hdr.flags, hdr.index, + hdr.start, hdr.count, + (void *)arg+minsz); + + return ret; - else if (cmd == VFIO_DEVICE_RESET) + } else if (cmd == VFIO_DEVICE_RESET) return -EINVAL; return -ENOTTY; diff --git a/drivers/vfio/platform/vfio_platform_irq.c b/drivers/vfio/platform/vfio_platform_irq.c index 075c401..433edc1 100644 --- a/drivers/vfio/platform/vfio_platform_irq.c +++ b/drivers/vfio/platform/vfio_platform_irq.c @@ -31,6 +31,9 @@ #include "vfio_platform_private.h" +static int vfio_set_trigger(struct vfio_platform_device *vdev, + int index, int fd); + int vfio_platform_irq_init(struct vfio_platform_device *vdev) { int cnt = 0, i; @@ -47,9 +50,11 @@ int vfio_platform_irq_init(struct vfio_platform_device *vdev) for (i = 0; i < cnt; i++) { struct vfio_platform_irq irq; + int hwirq = platform_get_irq(vdev->pdev, i); - irq.flags = 0; + irq.flags = VFIO_IRQ_INFO_EVENTFD; irq.count = 1; + irq.hwirq = hwirq; vdev->irq[i] = irq; } @@ -59,5 +64,121 @@ int vfio_platform_irq_init(struct vfio_platform_device *vdev) 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); + kfree(vdev->irq); } + +static irqreturn_t vfio_irq_handler(int irq, void *dev_id) +{ + struct eventfd_ctx *trigger = dev_id; + + eventfd_signal(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->irq[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->pdev->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) +{ + struct vfio_platform_irq *irq = &vdev->irq[index]; + uint8_t arr; + 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(&arr, data, sizeof(uint8_t))) + return -EFAULT; + + if (arr == 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, + uint32_t flags, unsigned index, unsigned start, + unsigned count, void *data) +{ + int (*func)(struct vfio_platform_device *vdev, unsigned index, + unsigned start, unsigned count, uint32_t flags, + void *data) = NULL; + + switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) { + case VFIO_IRQ_SET_ACTION_MASK: + case VFIO_IRQ_SET_ACTION_UNMASK: + /* XXX not implemented */ + break; + case VFIO_IRQ_SET_ACTION_TRIGGER: + func = vfio_platform_set_irq_trigger; + break; + } + + if (!func) + return -ENOTTY; + + return func(vdev, index, start, count, flags, data); +} diff --git a/drivers/vfio/platform/vfio_platform_private.h b/drivers/vfio/platform/vfio_platform_private.h index 9776cff..e21c15a 100644 --- a/drivers/vfio/platform/vfio_platform_private.h +++ b/drivers/vfio/platform/vfio_platform_private.h @@ -25,8 +25,11 @@ ((u64)(index) << VFIO_PLATFORM_OFFSET_SHIFT) struct vfio_platform_irq { + struct eventfd_ctx *trigger; u32 flags; u32 count; + int hwirq; + char *name; }; struct vfio_platform_region { @@ -47,4 +50,8 @@ extern int vfio_platform_irq_init(struct vfio_platform_device *vdev); extern void vfio_platform_irq_cleanup(struct vfio_platform_device *vdev); +extern int vfio_platform_set_irqs_ioctl(struct vfio_platform_device *vdev, + uint32_t flags, unsigned index, unsigned start, + unsigned count, void *data); + #endif /* VFIO_PLATFORM_PRIVATE_H */ -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/