From a717072007e8aedd3f951726d8cf55454860b30d Mon Sep 17 00:00:00 2001 From: Shameer Kolothum Date: Tue, 23 Jul 2019 17:06:36 +0100 Subject: vfio/type1: Add IOVA range capability support This allows the user-space to retrieve the supported IOVA range(s), excluding any non-relaxable reserved regions. The implementation is based on capability chains, added to VFIO_IOMMU_GET_INFO ioctl. Signed-off-by: Shameer Kolothum Reviewed-by: Eric Auger Signed-off-by: Alex Williamson --- drivers/vfio/vfio_iommu_type1.c | 101 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 101 insertions(+) (limited to 'drivers/vfio') diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index 56cf55776d6c..d0c5e768acb7 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -2138,6 +2138,73 @@ static int vfio_domains_have_iommu_cache(struct vfio_iommu *iommu) return ret; } +static int vfio_iommu_iova_add_cap(struct vfio_info_cap *caps, + struct vfio_iommu_type1_info_cap_iova_range *cap_iovas, + size_t size) +{ + struct vfio_info_cap_header *header; + struct vfio_iommu_type1_info_cap_iova_range *iova_cap; + + header = vfio_info_cap_add(caps, size, + VFIO_IOMMU_TYPE1_INFO_CAP_IOVA_RANGE, 1); + if (IS_ERR(header)) + return PTR_ERR(header); + + iova_cap = container_of(header, + struct vfio_iommu_type1_info_cap_iova_range, + header); + iova_cap->nr_iovas = cap_iovas->nr_iovas; + memcpy(iova_cap->iova_ranges, cap_iovas->iova_ranges, + cap_iovas->nr_iovas * sizeof(*cap_iovas->iova_ranges)); + return 0; +} + +static int vfio_iommu_iova_build_caps(struct vfio_iommu *iommu, + struct vfio_info_cap *caps) +{ + struct vfio_iommu_type1_info_cap_iova_range *cap_iovas; + struct vfio_iova *iova; + size_t size; + int iovas = 0, i = 0, ret; + + mutex_lock(&iommu->lock); + + list_for_each_entry(iova, &iommu->iova_list, list) + iovas++; + + if (!iovas) { + /* + * Return 0 as a container with a single mdev device + * will have an empty list + */ + ret = 0; + goto out_unlock; + } + + size = sizeof(*cap_iovas) + (iovas * sizeof(*cap_iovas->iova_ranges)); + + cap_iovas = kzalloc(size, GFP_KERNEL); + if (!cap_iovas) { + ret = -ENOMEM; + goto out_unlock; + } + + cap_iovas->nr_iovas = iovas; + + list_for_each_entry(iova, &iommu->iova_list, list) { + cap_iovas->iova_ranges[i].start = iova->start; + cap_iovas->iova_ranges[i].end = iova->end; + i++; + } + + ret = vfio_iommu_iova_add_cap(caps, cap_iovas, size); + + kfree(cap_iovas); +out_unlock: + mutex_unlock(&iommu->lock); + return ret; +} + static long vfio_iommu_type1_ioctl(void *iommu_data, unsigned int cmd, unsigned long arg) { @@ -2159,19 +2226,53 @@ static long vfio_iommu_type1_ioctl(void *iommu_data, } } else if (cmd == VFIO_IOMMU_GET_INFO) { struct vfio_iommu_type1_info info; + struct vfio_info_cap caps = { .buf = NULL, .size = 0 }; + unsigned long capsz; + int ret; minsz = offsetofend(struct vfio_iommu_type1_info, iova_pgsizes); + /* For backward compatibility, cannot require this */ + capsz = offsetofend(struct vfio_iommu_type1_info, cap_offset); + if (copy_from_user(&info, (void __user *)arg, minsz)) return -EFAULT; if (info.argsz < minsz) return -EINVAL; + if (info.argsz >= capsz) { + minsz = capsz; + info.cap_offset = 0; /* output, no-recopy necessary */ + } + info.flags = VFIO_IOMMU_INFO_PGSIZES; info.iova_pgsizes = vfio_pgsize_bitmap(iommu); + ret = vfio_iommu_iova_build_caps(iommu, &caps); + if (ret) + return ret; + + if (caps.size) { + info.flags |= VFIO_IOMMU_INFO_CAPS; + + if (info.argsz < sizeof(info) + caps.size) { + info.argsz = sizeof(info) + caps.size; + } else { + vfio_info_cap_shift(&caps, sizeof(info)); + if (copy_to_user((void __user *)arg + + sizeof(info), caps.buf, + caps.size)) { + kfree(caps.buf); + return -EFAULT; + } + info.cap_offset = sizeof(info); + } + + kfree(caps.buf); + } + return copy_to_user((void __user *)arg, &info, minsz) ? -EFAULT : 0; -- cgit