Adds support to mask interrupts, and also for automasked interrupts. Level sensitive interrupts are exposed as automasked interrupts and are masked and disabled automatically when they fire.
Signed-off-by: Antonios Motakis <a.mota...@virtualopensystems.com> --- drivers/vfio/platform/vfio_platform_irq.c | 120 ++++++++++++++++++++++++-- drivers/vfio/platform/vfio_platform_private.h | 2 + 2 files changed, 117 insertions(+), 5 deletions(-) diff --git a/drivers/vfio/platform/vfio_platform_irq.c b/drivers/vfio/platform/vfio_platform_irq.c index 25a7825..90fa25a 100644 --- a/drivers/vfio/platform/vfio_platform_irq.c +++ b/drivers/vfio/platform/vfio_platform_irq.c @@ -31,27 +31,129 @@ #include "vfio_platform_private.h" +static void vfio_platform_mask(struct vfio_platform_irq *irq_ctx) +{ + unsigned long flags; + + spin_lock_irqsave(&irq_ctx->lock, flags); + + if (!irq_ctx->masked) { + disable_irq(irq_ctx->hwirq); + irq_ctx->masked = true; + } + + spin_unlock_irqrestore(&irq_ctx->lock, flags); +} + static int vfio_platform_set_irq_mask(struct vfio_platform_device *vdev, unsigned index, unsigned start, unsigned count, uint32_t flags, void *data) { - return -EINVAL; + uint8_t irq_bitmap; + + if (start != 0 || count != 1) + return -EINVAL; + + switch (flags & VFIO_IRQ_SET_DATA_TYPE_MASK) { + case VFIO_IRQ_SET_DATA_BOOL: + if (copy_from_user(&irq_bitmap, data, sizeof(uint8_t))) + return -EFAULT; + + if (irq_bitmap != 0x1) + return -EINVAL; + + /* + * The following fall through is both intentional and safe. + * VFIO_IRQ_SET_DATA_BOOL allows to handle an array of IRQs + * on the same index. For VFIO platform devices we always have + * one IRQ per index, so as soon as we check that the user + * provided bitmap only refers to one single IRQ, we can safely + * share the rest of the logic with VFIO_IRQ_SET_DATA_NONE. + */ + + case VFIO_IRQ_SET_DATA_NONE: + vfio_platform_mask(&vdev->irqs[index]); + return 0; + + case VFIO_IRQ_SET_DATA_EVENTFD: /* XXX not implemented yet */ + default: + return -ENOTTY; + } + + return 0; +} + +static void vfio_platform_unmask(struct vfio_platform_irq *irq_ctx) +{ + unsigned long flags; + + spin_lock_irqsave(&irq_ctx->lock, flags); + + if (irq_ctx->masked) { + enable_irq(irq_ctx->hwirq); + irq_ctx->masked = false; + } + + spin_unlock_irqrestore(&irq_ctx->lock, flags); } static int vfio_platform_set_irq_unmask(struct vfio_platform_device *vdev, unsigned index, unsigned start, unsigned count, uint32_t flags, void *data) { - return -EINVAL; + uint8_t irq_bitmap; + + if (start != 0 || count != 1) + return -EINVAL; + + switch (flags & VFIO_IRQ_SET_DATA_TYPE_MASK) { + case VFIO_IRQ_SET_DATA_BOOL: + if (copy_from_user(&irq_bitmap, data, sizeof(uint8_t))) + return -EFAULT; + + if (irq_bitmap != 0x1) + return -EINVAL; + + /* + * The following fall through is both intentional and safe, + * as in vfio_platform_set_irq_mask(). + */ + + case VFIO_IRQ_SET_DATA_NONE: + vfio_platform_unmask(&vdev->irqs[index]); + return 0; + + case VFIO_IRQ_SET_DATA_EVENTFD: /* XXX not implemented yet */ + default: + return -ENOTTY; + } + + return 0; } static irqreturn_t vfio_irq_handler(int irq, void *dev_id) { struct vfio_platform_irq *irq_ctx = dev_id; + unsigned long flags; + int ret = IRQ_NONE; - eventfd_signal(irq_ctx->trigger, 1); + spin_lock_irqsave(&irq_ctx->lock, flags); - return IRQ_HANDLED; + if (!irq_ctx->masked) { + ret = IRQ_HANDLED; + + if (irq_ctx->flags & VFIO_IRQ_INFO_AUTOMASKED) { + disable_irq_nosync(irq_ctx->hwirq); + irq_ctx->masked = true; + } + } + + spin_unlock_irqrestore(&irq_ctx->lock, flags); + + if (ret == IRQ_HANDLED) + eventfd_signal(irq_ctx->trigger, 1); + + return ret; } static int vfio_set_trigger(struct vfio_platform_device *vdev, @@ -175,9 +277,17 @@ int vfio_platform_irq_init(struct vfio_platform_device *vdev) if (hwirq < 0) goto err; - vdev->irqs[i].flags = VFIO_IRQ_INFO_EVENTFD; + spin_lock_init(&vdev->irqs[i].lock); + + vdev->irqs[i].flags = VFIO_IRQ_INFO_EVENTFD + | VFIO_IRQ_INFO_MASKABLE; + + if (irq_get_trigger_type(hwirq) & IRQ_TYPE_LEVEL_MASK) + vdev->irqs[i].flags |= VFIO_IRQ_INFO_AUTOMASKED; + vdev->irqs[i].count = 1; vdev->irqs[i].hwirq = hwirq; + vdev->irqs[i].masked = false; } vdev->num_irqs = cnt; diff --git a/drivers/vfio/platform/vfio_platform_private.h b/drivers/vfio/platform/vfio_platform_private.h index 765b371..500e299 100644 --- a/drivers/vfio/platform/vfio_platform_private.h +++ b/drivers/vfio/platform/vfio_platform_private.h @@ -30,6 +30,8 @@ struct vfio_platform_irq { int hwirq; char *name; struct eventfd_ctx *trigger; + bool masked; + spinlock_t lock; }; struct vfio_platform_region { -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html