Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751841AbaJZMB1 (ORCPT ); Sun, 26 Oct 2014 08:01:27 -0400 Received: from mx1.redhat.com ([209.132.183.28]:60047 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751517AbaJZMB0 (ORCPT ); Sun, 26 Oct 2014 08:01:26 -0400 Date: Sun, 26 Oct 2014 14:01:03 +0200 From: "Michael S. Tsirkin" To: "john.liuli" Cc: linux-kernel@vger.kernel.org, qemu-devel@nongnu.org, peter.huangpeng@huawei.com, rusty@rustcorp.com.au, virtualization@lists.linux-foundation.org, n.nikolaev@virtualopensystems.com, yingshiuan.pan@gmail.com, remy.gauguey@cea.fr, joel.schopp@amd.com Subject: Re: [RFC PATCH 1/2] Add a new register offset let interrupt reason available Message-ID: <20141026120103.GC5497@redhat.com> References: <1414225494-2208-1-git-send-email-john.liuli@huawei.com> <1414225494-2208-2-git-send-email-john.liuli@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1414225494-2208-2-git-send-email-john.liuli@huawei.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Oct 25, 2014 at 04:24:53PM +0800, john.liuli wrote: > From: Li Liu > > Add a new register offset VIRTIO_MMIO_ISRMEM which help to > estblish a shared memory region between virtio-mmio driver > and qemu with two purposes: > > 1.Guest virtio-mmio driver can get the interrupt reason. > 2.Check irqfd enabled or not to register different irq handler. > > Signed-off-by: Li Liu > --- > drivers/virtio/virtio_mmio.c | 21 ++++++++++++++++++++- > include/linux/virtio_mmio.h | 3 +++ > 2 files changed, 23 insertions(+), 1 deletion(-) > > diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c > index ef9a165..28ddb55 100644 > --- a/drivers/virtio/virtio_mmio.c > +++ b/drivers/virtio/virtio_mmio.c > @@ -122,6 +122,8 @@ struct virtio_mmio_device { > /* a list of queues so we can dispatch IRQs */ > spinlock_t lock; > struct list_head virtqueues; > + > + uint8_t *isr_mem; > }; > > struct virtio_mmio_vq_info { > @@ -443,6 +445,7 @@ static int virtio_mmio_probe(struct platform_device *pdev) > struct virtio_mmio_device *vm_dev; > struct resource *mem; > unsigned long magic; > + int err; > > mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); > if (!mem) > @@ -481,6 +484,15 @@ static int virtio_mmio_probe(struct platform_device *pdev) > return -ENXIO; > } > > + vm_dev->isr_mem = alloc_pages_exact(PAGE_SIZE, GFP_KERNEL|__GFP_ZERO); > + if (vm_dev->isr_mem == NULL) { > + dev_err(&pdev->dev, "Allocate isr memory failed!\n"); > + return -ENOMEM; > + } > + > + writel(virt_to_phys(vm_dev->isr_mem), > + vm_dev->base + VIRTIO_MMIO_ISRMEM); > + What happens to existing devices? then might not expect writes at this address. > vm_dev->vdev.id.device = readl(vm_dev->base + VIRTIO_MMIO_DEVICE_ID); > vm_dev->vdev.id.vendor = readl(vm_dev->base + VIRTIO_MMIO_VENDOR_ID); > > @@ -488,13 +500,20 @@ static int virtio_mmio_probe(struct platform_device *pdev) > > platform_set_drvdata(pdev, vm_dev); > > - return register_virtio_device(&vm_dev->vdev); > + err = register_virtio_device(&vm_dev->vdev); > + if (err) { > + free_pages_exact(vm_dev->isr_mem, PAGE_SIZE); > + vm_dev->isr_mem = NULL; > + } > + > + return err; > } > > static int virtio_mmio_remove(struct platform_device *pdev) > { > struct virtio_mmio_device *vm_dev = platform_get_drvdata(pdev); > > + free_pages_exact(vm_dev->isr_mem, PAGE_SIZE); > unregister_virtio_device(&vm_dev->vdev); > > return 0; > diff --git a/include/linux/virtio_mmio.h b/include/linux/virtio_mmio.h > index 5c7b6f0..b1e3ec7 100644 > --- a/include/linux/virtio_mmio.h > +++ b/include/linux/virtio_mmio.h > @@ -95,6 +95,9 @@ > /* Device status register - Read Write */ > #define VIRTIO_MMIO_STATUS 0x070 > > +/* Allocate ISRMEM for interrupt reason - Write Only */ > +#define VIRTIO_MMIO_ISRMEM 0x080 > + > /* The config space is defined by each driver as > * the per-driver configuration space - Read Write */ > #define VIRTIO_MMIO_CONFIG 0x100 > -- > 1.7.9.5 > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/