@@ -844,6 +844,41 @@ vfio_get_region_info_cap(struct vfio_region_info *info, uint16_t id)
return NULL;
}
+static struct vfio_info_cap_header *
+vfio_get_iommu_type1_info_cap(struct vfio_iommu_type1_info *info, uint16_t id)
+{
+ struct vfio_info_cap_header *hdr;
+ void *ptr = info;
+
+ if (!(info->flags & VFIO_IOMMU_INFO_CAPS)) {
+ return NULL;
+ }
+
+ for (hdr = ptr + info->cap_offset; hdr != ptr; hdr = ptr + hdr->next) {
+ if (hdr->id == id) {
+ return hdr;
+ }
+ }
+
+ return NULL;
+}
+
+static unsigned int vfio_get_info_dma_limit(struct vfio_iommu_type1_info *info)
+{
+ struct vfio_info_cap_header *hdr;
+ struct vfio_iommu_type1_info_dma_limit *cap;
+
+ /* If the capability cannot be found, assume no DMA limiting */
+ hdr = vfio_get_iommu_type1_info_cap(info,
+ VFIO_IOMMU_TYPE1_INFO_DMA_LIMIT);
+ if (hdr == NULL) {
+ return 0;
+ }
+
+ cap = (void *) hdr;
+ return cap->max;
+}
+
static int vfio_setup_region_sparse_mmaps(VFIORegion *region,
struct vfio_region_info *info)
{
@@ -1285,7 +1320,8 @@ static int vfio_connect_container(VFIOGroup *group, AddressSpace *as,
case VFIO_TYPE1v2_IOMMU:
case VFIO_TYPE1_IOMMU:
{
- struct vfio_iommu_type1_info info;
+ struct vfio_iommu_type1_info *info;
+ uint32_t argsz;
/*
* FIXME: This assumes that a Type1 IOMMU can map any 64-bit
@@ -1294,15 +1330,37 @@ static int vfio_connect_container(VFIOGroup *group, AddressSpace *as,
* existing Type1 IOMMUs generally support any IOVA we're
* going to actually try in practice.
*/
- info.argsz = sizeof(info);
- ret = ioctl(fd, VFIO_IOMMU_GET_INFO, &info);
- /* Ignore errors */
- if (ret || !(info.flags & VFIO_IOMMU_INFO_PGSIZES)) {
- /* Assume 4k IOVA page size */
- info.iova_pgsizes = 4096;
+ argsz = sizeof(struct vfio_iommu_type1_info);
+ info = g_malloc0(argsz);
+ info->argsz = argsz;
+ /*
+ * If the specified argsz is not large enough to contain all
+ * capabilities it will be updated upon return. In this case
+ * use the updated value to get the entire capability chain.
+ */
+ ret = ioctl(fd, VFIO_IOMMU_GET_INFO, info);
+ if (argsz != info->argsz) {
+ argsz = info->argsz;
+ info = g_realloc(info, argsz);
+ info->argsz = argsz;
+ ret = ioctl(fd, VFIO_IOMMU_GET_INFO, info);
+ }
+ /* Set defaults on error */
+ if (ret) {
+ /* Assume 4k IOVA page size and no DMA limiting */
+ info->iova_pgsizes = 4096;
+ container->dma_limit = 0;
+ } else {
+ if (!(info->flags & VFIO_IOMMU_INFO_PGSIZES)) {
+ /* Assume 4k IOVA page size */
+ info->iova_pgsizes = 4096;
+ }
+ /* Obtain DMA limit from capability chain */
+ container->dma_limit = vfio_get_info_dma_limit(info);
}
- vfio_host_win_add(container, 0, (hwaddr)-1, info.iova_pgsizes);
- container->pgsizes = info.iova_pgsizes;
+ vfio_host_win_add(container, 0, (hwaddr)-1, info->iova_pgsizes);
+ container->pgsizes = info->iova_pgsizes;
+ g_free(info);
break;
}
case VFIO_SPAPR_TCE_v2_IOMMU:
@@ -74,6 +74,7 @@ typedef struct VFIOContainer {
Error *error;
bool initialized;
unsigned long pgsizes;
+ unsigned int dma_limit;
QLIST_HEAD(, VFIOGuestIOMMU) giommu_list;
QLIST_HEAD(, VFIOHostDMAWindow) hostwin_list;
QLIST_HEAD(, VFIOGroup) group_list;
The underlying host may be limiting the number of outstanding DMA requests for type 1 IOMMU. Determine if this is the case and if so retrieve the number of outstanding mappings allowed. Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com> --- hw/vfio/common.c | 76 ++++++++++++++++++++++++++++++++++++++----- include/hw/vfio/vfio-common.h | 1 + 2 files changed, 68 insertions(+), 9 deletions(-)