From ad146355bfad627bd0717ece73997c6c93b1b82e Mon Sep 17 00:00:00 2001 From: Xie Yongji Date: Wed, 3 Aug 2022 12:55:23 +0800 Subject: [PATCH] vduse: Support querying information of IOVA regions This introduces a new ioctl: VDUSE_IOTLB_GET_INFO to support querying some information of IOVA regions. Now it can be used to query whether the IOVA region supports userspace memory registration. Signed-off-by: Xie Yongji Message-Id: <20220803045523.23851-6-xieyongji@bytedance.com> Signed-off-by: Michael S. Tsirkin Acked-by: Jason Wang --- drivers/vdpa/vdpa_user/vduse_dev.c | 39 ++++++++++++++++++++++++++++++++++++++ include/uapi/linux/vduse.h | 24 +++++++++++++++++++++++ 2 files changed, 63 insertions(+) diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c index eedff0a..41c0b29 100644 --- a/drivers/vdpa/vdpa_user/vduse_dev.c +++ b/drivers/vdpa/vdpa_user/vduse_dev.c @@ -1228,6 +1228,45 @@ static long vduse_dev_ioctl(struct file *file, unsigned int cmd, umem.size); break; } + case VDUSE_IOTLB_GET_INFO: { + struct vduse_iova_info info; + struct vhost_iotlb_map *map; + struct vduse_iova_domain *domain = dev->domain; + + ret = -EFAULT; + if (copy_from_user(&info, argp, sizeof(info))) + break; + + ret = -EINVAL; + if (info.start > info.last) + break; + + if (!is_mem_zero((const char *)info.reserved, + sizeof(info.reserved))) + break; + + spin_lock(&domain->iotlb_lock); + map = vhost_iotlb_itree_first(domain->iotlb, + info.start, info.last); + if (map) { + info.start = map->start; + info.last = map->last; + info.capability = 0; + if (domain->bounce_map && map->start == 0 && + map->last == domain->bounce_size - 1) + info.capability |= VDUSE_IOVA_CAP_UMEM; + } + spin_unlock(&domain->iotlb_lock); + if (!map) + break; + + ret = -EFAULT; + if (copy_to_user(argp, &info, sizeof(info))) + break; + + ret = 0; + break; + } default: ret = -ENOIOCTLCMD; break; diff --git a/include/uapi/linux/vduse.h b/include/uapi/linux/vduse.h index 9885e05..11bd48c 100644 --- a/include/uapi/linux/vduse.h +++ b/include/uapi/linux/vduse.h @@ -233,6 +233,30 @@ struct vduse_iova_umem { /* De-register the userspace memory. Caller should set iova and size field. */ #define VDUSE_IOTLB_DEREG_UMEM _IOW(VDUSE_BASE, 0x19, struct vduse_iova_umem) +/** + * struct vduse_iova_info - information of one IOVA region + * @start: start of the IOVA region + * @last: last of the IOVA region + * @capability: capability of the IOVA regsion + * @reserved: for future use, needs to be initialized to zero + * + * Structure used by VDUSE_IOTLB_GET_INFO ioctl to get information of + * one IOVA region. + */ +struct vduse_iova_info { + __u64 start; + __u64 last; +#define VDUSE_IOVA_CAP_UMEM (1 << 0) + __u64 capability; + __u64 reserved[3]; +}; + +/* + * Find the first IOVA region that overlaps with the range [start, last] + * and return some information on it. Caller should set start and last fields. + */ +#define VDUSE_IOTLB_GET_INFO _IOWR(VDUSE_BASE, 0x1a, struct vduse_iova_info) + /* The control messages definition for read(2)/write(2) on /dev/vduse/$NAME */ /** -- 2.7.4