VFIO exposes host IOMMU dual-stage DMA translation programming capability to userspace by VFIO_TYPE1_NESTING_IOMMU type. However, userspace needs more info on the nesting type. e.g. the supported stage 1 format and PASID alloc/free request availability. This patch gets the iommu nesting cap info from kernel by using IOCTL VFIO_IOMMU_GET_INFO. This patch referred some code from Shameer Kolothum. https://lists.gnu.org/archive/html/qemu-devel/2018-05/msg03759.html Cc: Kevin Tian <kevin.tian@xxxxxxxxx> Cc: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx> Cc: Peter Xu <peterx@xxxxxxxxxx> Cc: Eric Auger <eric.auger@xxxxxxxxxx> Cc: Yi Sun <yi.y.sun@xxxxxxxxxxxxxxx> Cc: David Gibson <david@xxxxxxxxxxxxxxxxxxxxx> Cc: Alex Williamson <alex.williamson@xxxxxxxxxx> Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@xxxxxxxxxx> Signed-off-by: Liu Yi L <yi.l.liu@xxxxxxxxx> --- hw/iommu/host_iommu_context.c | 5 +- hw/vfio/common.c | 97 ++++++++++++++++++++++++++++++++++- include/hw/iommu/host_iommu_context.h | 10 +++- 3 files changed, 108 insertions(+), 4 deletions(-) diff --git a/hw/iommu/host_iommu_context.c b/hw/iommu/host_iommu_context.c index 11b092f..689a087 100644 --- a/hw/iommu/host_iommu_context.c +++ b/hw/iommu/host_iommu_context.c @@ -42,10 +42,13 @@ int host_iommu_ctx_pasid_free(HostIOMMUContext *host_icx, uint32_t pasid) } void host_iommu_ctx_init(HostIOMMUContext *host_icx, - uint64_t flags, HostIOMMUOps *ops) + uint64_t flags, HostIOMMUOps *ops, + HostIOMMUInfo *uinfo) { host_icx->flags = flags; host_icx->ops = ops; + + host_icx->uinfo.stage1_format = uinfo->stage1_format; } void host_iommu_ctx_destroy(HostIOMMUContext *host_icx) diff --git a/hw/vfio/common.c b/hw/vfio/common.c index 9ab62a6..f9be68d 100644 --- a/hw/vfio/common.c +++ b/hw/vfio/common.c @@ -1183,6 +1183,84 @@ static struct HostIOMMUOps vfio_host_icx_ops = { /* To be added later */ }; +/** + * Get iommu info from host. Caller of this funcion should free + * the memory pointed by the returned pointer stored in @info + * after a successful calling when finished its usage. + */ +static int vfio_get_iommu_info(VFIOContainer *container, + struct vfio_iommu_type1_info **info) +{ + + size_t argsz = sizeof(struct vfio_iommu_type1_info); + + *info = g_malloc0(argsz); + +retry: + (*info)->argsz = argsz; + + if (ioctl(container->fd, VFIO_IOMMU_GET_INFO, *info)) { + g_free(*info); + *info = NULL; + return -errno; + } + + if (((*info)->argsz > argsz)) { + argsz = (*info)->argsz; + *info = g_realloc(*info, argsz); + goto retry; + } + + return 0; +} + +static struct vfio_info_cap_header * +vfio_get_iommu_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 int vfio_get_nesting_iommu_cap(VFIOContainer *container, + struct vfio_iommu_type1_info_cap_nesting *cap_nesting) +{ + struct vfio_iommu_type1_info *info; + struct vfio_info_cap_header *hdr; + struct vfio_iommu_type1_info_cap_nesting *cap; + int ret; + + ret = vfio_get_iommu_info(container, &info); + if (ret) { + return ret; + } + + hdr = vfio_get_iommu_info_cap(info, + VFIO_IOMMU_TYPE1_INFO_CAP_NESTING); + if (!hdr) { + g_free(info); + return -errno; + } + + cap = container_of(hdr, + struct vfio_iommu_type1_info_cap_nesting, header); + *cap_nesting = *cap; + + g_free(info); + return 0; +} + static int vfio_init_container(VFIOContainer *container, int group_fd, Error **errp) { @@ -1216,8 +1294,23 @@ static int vfio_init_container(VFIOContainer *container, int group_fd, } if (iommu_type == VFIO_TYPE1_NESTING_IOMMU) { - host_iommu_ctx_init(&container->host_icx, - flags, &vfio_host_icx_ops); + struct vfio_iommu_type1_info_cap_nesting nesting = { + .nesting_capabilities = 0x0, + .stage1_format = 0, }; + HostIOMMUInfo uinfo; + + ret = vfio_get_nesting_iommu_cap(container, &nesting); + if (ret) { + error_setg_errno(errp, -ret, + "Failed to get nesting iommu cap"); + return ret; + } + + uinfo.stage1_format = nesting.stage1_format; + flags |= (nesting.nesting_capabilities & VFIO_IOMMU_PASID_REQS) ? + HOST_IOMMU_PASID_REQUEST : 0; + host_iommu_ctx_init(&container->host_icx, flags, + &vfio_host_icx_ops, &uinfo); } container->iommu_type = iommu_type; diff --git a/include/hw/iommu/host_iommu_context.h b/include/hw/iommu/host_iommu_context.h index f4d811a..6797f6d 100644 --- a/include/hw/iommu/host_iommu_context.h +++ b/include/hw/iommu/host_iommu_context.h @@ -23,12 +23,14 @@ #define HW_IOMMU_CONTEXT_H #include "qemu/queue.h" +#include <linux/iommu.h> #ifndef CONFIG_USER_ONLY #include "exec/hwaddr.h" #endif typedef struct HostIOMMUContext HostIOMMUContext; typedef struct HostIOMMUOps HostIOMMUOps; +typedef struct HostIOMMUInfo HostIOMMUInfo; struct HostIOMMUOps { /* Allocate pasid from HostIOMMUContext (a.k.a. host software) */ @@ -41,6 +43,10 @@ struct HostIOMMUOps { uint32_t pasid); }; +struct HostIOMMUInfo { + uint32_t stage1_format; +}; + /* * This is an abstraction of host IOMMU with dual-stage capability */ @@ -48,6 +54,7 @@ struct HostIOMMUContext { #define HOST_IOMMU_PASID_REQUEST (1ULL << 0) uint64_t flags; HostIOMMUOps *ops; + HostIOMMUInfo uinfo; }; int host_iommu_ctx_pasid_alloc(HostIOMMUContext *host_icx, uint32_t min, @@ -55,7 +62,8 @@ int host_iommu_ctx_pasid_alloc(HostIOMMUContext *host_icx, uint32_t min, int host_iommu_ctx_pasid_free(HostIOMMUContext *host_icx, uint32_t pasid); void host_iommu_ctx_init(HostIOMMUContext *host_icx, - uint64_t flags, HostIOMMUOps *ops); + uint64_t flags, HostIOMMUOps *ops, + HostIOMMUInfo *uinfo); void host_iommu_ctx_destroy(HostIOMMUContext *host_icx); #endif -- 2.7.4