Subject: [PATCH] virtio_pci updates From: Anthony Liguori Date: Sat, 10 Nov 2007 16:12:12 -0600 This patch brings the virtio_pci driver up-to-date with what I have locally. It fixes a bug with destroying a virtqueue, switches to kmalloc so we can support rings > PAGE_SIZE, and fixes a bug with odd sized configuration entries. Signed-off-by: Anthony Liguori Signed-off-by: Rusty Russell diff -r 9e60bfaa0c3c drivers/virtio/virtio_pci.c --- a/drivers/virtio/virtio_pci.c Tue Nov 13 14:44:42 2007 +1100 +++ b/drivers/virtio/virtio_pci.c Tue Nov 13 14:47:12 2007 +1100 @@ -1,3 +1,19 @@ +/* + * Virtio PCI driver + * + * This module allows virtio devices to be used over a virtual PCI device. + * This can be used with QEMU based VMMs like KVM or Xen. + * + * Copyright IBM Corp. 2007 + * + * Authors: + * Anthony Liguori + * + * This work is licensed under the terms of the GNU GPL, version 2. See + * the COPYING file in the top-level directory. + * + */ + #include #include #include @@ -17,32 +33,32 @@ MODULE_VERSION("1"); /* Our device structure */ struct virtio_pci_device { - /* the virtio device */ struct virtio_device vdev; - /* the PCI device */ struct pci_dev *pci_dev; + /* the IO mapping for the PCI config space */ void *ioaddr; + /* a list of queues so we can dispatch IRQs */ spinlock_t lock; struct list_head virtqueues; }; struct virtio_pci_vq_info { + /* the actual virtqueue */ + struct virtqueue *vq; + /* the number of entries in the queue */ int num; - /* the number of pages the device needs for the ring queue */ - int n_pages; + /* the index of the queue */ int queue_index; - /* the struct page of the ring queue */ - struct page *pages; + /* the virtual address of the ring queue */ void *queue; - /* a pointer to the virtqueue */ - struct virtqueue *vq; - /* the node pointer */ + + /* the list node for the virtqueues list */ struct list_head node; }; @@ -127,11 +143,14 @@ static void vp_get(struct virtio_device break; } - /* for strange accesses of an odd size, we do not perform any - * endianness conversion. */ - default: - ioread8_rep(ioaddr, buf, len); - break; + default: { + uint8_t *ptr = buf; + int i; + + for (i = 0; i < len; i++) + ptr[i] = ioread8(ioaddr + i); + break; + } } } @@ -169,9 +188,14 @@ static void vp_set(struct virtio_device iowrite32(val, ioaddr + 4); break; } - default: - iowrite8_rep(ioaddr, buf, len); - break; + default: { + const uint8_t *ptr = buf; + int i; + + for (i = 0; i < len; i++) + iowrite8(ptr[i], ioaddr + i); + break; + } } } @@ -237,8 +261,8 @@ static struct virtqueue *vp_find_vq(stru struct virtio_pci_device *vp_dev = to_vp_device(vdev); struct virtio_pci_vq_info *info; struct virtqueue *vq; + u16 num; int err; - u16 num; /* Select the queue we're interested in */ iowrite16(index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL); @@ -257,25 +281,14 @@ static struct virtqueue *vp_find_vq(stru info->queue_index = index; info->num = num; - /* determine the memory needed for the queue and provide the memory - * location to the host */ - info->n_pages = DIV_ROUND_UP(vring_size(num), PAGE_SIZE); - info->pages = alloc_pages(GFP_KERNEL | __GFP_ZERO, - get_order(info->n_pages)); - if (info->pages == NULL) { + info->queue = kmalloc(vring_size(num), GFP_KERNEL | __GFP_ZERO); + if (info->queue == NULL) { err = -ENOMEM; goto out_info; } - /* FIXME: is this sufficient for info->n_pages > 1? */ - info->queue = kmap(info->pages); - if (info->queue == NULL) { - err = -ENOMEM; - goto out_alloc_pages; - } - /* activate the queue */ - iowrite32(page_to_pfn(info->pages), + iowrite32(virt_to_phys(info->queue) >> PAGE_SHIFT, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN); /* create the vring */ @@ -297,9 +310,7 @@ static struct virtqueue *vp_find_vq(stru out_activate_queue: iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN); - kunmap(info->queue); -out_alloc_pages: - __free_pages(info->pages, get_order(info->n_pages)); + kfree(info->queue); out_info: kfree(info); return ERR_PTR(err); @@ -319,10 +330,9 @@ static void vp_del_vq(struct virtqueue * /* Select and deactivate the queue */ iowrite16(info->queue_index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL); - iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL); - - kunmap(info->queue); - __free_pages(info->pages, get_order(info->n_pages)); + iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN); + + kfree(info->queue); kfree(info); } @@ -348,10 +358,13 @@ static int __devinit virtio_pci_probe(st if (vp_dev == NULL) return -ENOMEM; + snprintf(vp_dev->vdev.dev.bus_id, BUS_ID_SIZE, "virtio%d", dev_index); + vp_dev->vdev.index = dev_index; + dev_index++; + + vp_dev->vdev.dev.parent = &virtio_pci_root; + vp_dev->vdev.config = &virtio_pci_config_ops; vp_dev->pci_dev = pci_dev; - vp_dev->vdev.dev.parent = &virtio_pci_root; - vp_dev->vdev.index = dev_index++; - vp_dev->vdev.config = &virtio_pci_config_ops; INIT_LIST_HEAD(&vp_dev->virtqueues); spin_lock_init(&vp_dev->lock); @@ -379,7 +392,7 @@ static int __devinit virtio_pci_probe(st /* register a handler for the queue with the PCI device's interrupt */ err = request_irq(vp_dev->pci_dev->irq, vp_interrupt, IRQF_SHARED, - pci_name(vp_dev->pci_dev), vp_dev); + vp_dev->vdev.dev.bus_id, vp_dev); if (err) goto out_set_drvdata; diff -r 9e60bfaa0c3c include/linux/virtio_pci.h --- a/include/linux/virtio_pci.h Tue Nov 13 14:44:42 2007 +1100 +++ b/include/linux/virtio_pci.h Tue Nov 13 14:47:12 2007 +1100 @@ -1,3 +1,19 @@ +/* + * Virtio PCI driver + * + * This module allows virtio devices to be used over a virtual PCI device. + * This can be used with QEMU based VMMs like KVM or Xen. + * + * Copyright IBM Corp. 2007 + * + * Authors: + * Anthony Liguori + * + * This work is licensed under the terms of the GNU GPL, version 2. See + * the COPYING file in the top-level directory. + * + */ + #ifndef _LINUX_VIRTIO_PCI_H #define _LINUX_VIRTIO_PCI_H