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 <shameerali.kolothum.thodi@huawei.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This commit is contained in:
Shameer Kolothum 2019-07-23 17:06:36 +01:00 committed by Alex Williamson
parent 9b77e5c798
commit a717072007
2 changed files with 126 additions and 1 deletions

View file

@ -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;

View file

@ -714,7 +714,31 @@ struct vfio_iommu_type1_info {
__u32 argsz;
__u32 flags;
#define VFIO_IOMMU_INFO_PGSIZES (1 << 0) /* supported page sizes info */
__u64 iova_pgsizes; /* Bitmap of supported page sizes */
#define VFIO_IOMMU_INFO_CAPS (1 << 1) /* Info supports caps */
__u64 iova_pgsizes; /* Bitmap of supported page sizes */
__u32 cap_offset; /* Offset within info struct of first cap */
};
/*
* The IOVA capability allows to report the valid IOVA range(s)
* excluding any non-relaxable reserved regions exposed by
* devices attached to the container. Any DMA map attempt
* outside the valid iova range will return error.
*
* The structures below define version 1 of this capability.
*/
#define VFIO_IOMMU_TYPE1_INFO_CAP_IOVA_RANGE 1
struct vfio_iova_range {
__u64 start;
__u64 end;
};
struct vfio_iommu_type1_info_cap_iova_range {
struct vfio_info_cap_header header;
__u32 nr_iovas;
__u32 reserved;
struct vfio_iova_range iova_ranges[];
};
#define VFIO_IOMMU_GET_INFO _IO(VFIO_TYPE, VFIO_BASE + 12)