From: Saurabh Sengar Date: Sat, 30 Mar 2024 08:51:59 +0000 (-0700) Subject: uio_hv_generic: Enable interrupt for low speed VMBus devices X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=547fa4ffd799ad48bf96e60efd24985adeec35de;p=linux.git uio_hv_generic: Enable interrupt for low speed VMBus devices Hyper-V is adding some "specialty" synthetic devices. Instead of writing new kernel-level VMBus drivers for these devices, the devices will be presented to user space via this existing Hyper-V generic UIO driver, so that a user space driver can handle the device. Since these new synthetic devices are low speed devices, they don't support monitor bits and we must use vmbus_setevent() to enable interrupts from the host. Signed-off-by: Saurabh Sengar Reviewed-by: Long Li Link: https://lore.kernel.org/r/1711788723-8593-4-git-send-email-ssengar@linux.microsoft.com Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/uio/uio_hv_generic.c b/drivers/uio/uio_hv_generic.c index 4bda6b52e49ea..289611c7dfd79 100644 --- a/drivers/uio/uio_hv_generic.c +++ b/drivers/uio/uio_hv_generic.c @@ -84,6 +84,9 @@ hv_uio_irqcontrol(struct uio_info *info, s32 irq_state) dev->channel->inbound.ring_buffer->interrupt_mask = !irq_state; virt_mb(); + if (!dev->channel->offermsg.monitor_allocated && irq_state) + vmbus_setevent(dev->channel); + return 0; } @@ -240,12 +243,6 @@ hv_uio_probe(struct hv_device *dev, int ret; size_t ring_size = hv_dev_ring_size(channel); - /* Communicating with host has to be via shared memory not hypercall */ - if (!channel->offermsg.monitor_allocated) { - dev_err(&dev->device, "vmbus channel requires hypercall\n"); - return -ENOTSUPP; - } - if (!ring_size) ring_size = HV_RING_SIZE * PAGE_SIZE;