Hi Zhenzhong,
On 5/30/25 11:35 AM, Zhenzhong Duan wrote:
> This helper passes cache invalidation request from guest to invalidate
> stage-1 page table cache in host hardware.
>
> Signed-off-by: Nicolin Chen <nicol...@nvidia.com>
> Signed-off-by: Zhenzhong Duan <zhenzhong.d...@intel.com>
> ---
> include/system/iommufd.h | 4 ++++
> backends/iommufd.c | 36 ++++++++++++++++++++++++++++++++++++
> backends/trace-events | 1 +
> 3 files changed, 41 insertions(+)
>
> diff --git a/include/system/iommufd.h b/include/system/iommufd.h
> index cbab75bfbf..83ab8e1e4c 100644
> --- a/include/system/iommufd.h
> +++ b/include/system/iommufd.h
> @@ -61,6 +61,10 @@ bool iommufd_backend_get_dirty_bitmap(IOMMUFDBackend *be,
> uint32_t hwpt_id,
> uint64_t iova, ram_addr_t size,
> uint64_t page_size, uint64_t *data,
> Error **errp);
> +bool iommufd_backend_invalidate_cache(IOMMUFDBackend *be, uint32_t id,
> + uint32_t data_type, uint32_t entry_len,
> + uint32_t *entry_num, void *data,
> + Error **errp);
>
> #define TYPE_HOST_IOMMU_DEVICE_IOMMUFD TYPE_HOST_IOMMU_DEVICE "-iommufd"
> #endif
> diff --git a/backends/iommufd.c b/backends/iommufd.c
> index b73f75cd0b..8bcdb60fe7 100644
> --- a/backends/iommufd.c
> +++ b/backends/iommufd.c
> @@ -311,6 +311,42 @@ bool iommufd_backend_get_device_info(IOMMUFDBackend *be,
> uint32_t devid,
> return true;
> }
>
> +bool iommufd_backend_invalidate_cache(IOMMUFDBackend *be, uint32_t id,
> + uint32_t data_type, uint32_t entry_len,
> + uint32_t *entry_num, void *data,
> + Error **errp)
> +{
> + int ret, fd = be->fd;
> + uint32_t total_entries = *entry_num;
> + struct iommu_hwpt_invalidate cache = {
> + .size = sizeof(cache),
> + .hwpt_id = id,
> + .data_type = data_type,
> + .entry_len = entry_len,
> + .entry_num = total_entries,
> + .data_uptr = (uintptr_t)data,
> + };
> +
> + ret = ioctl(fd, IOMMU_HWPT_INVALIDATE, &cache);
> + trace_iommufd_backend_invalidate_cache(fd, id, data_type, entry_len,
> + total_entries, cache.entry_num,
> + (uintptr_t)data, ret ? errno : 0);
> + *entry_num = cache.entry_num;
> +
> + if (ret) {
> + error_setg_errno(errp, errno, "IOMMU_HWPT_INVALIDATE failed:"
> + " total %d entries, processed %d entries",
> + total_entries, cache.entry_num);
> + } else if (total_entries != cache.entry_num) {
> + error_setg(errp, "IOMMU_HWPT_INVALIDATE succeed but with unprocessed"
> + " entries: total %d entries, processed %d entries."
> + " Kernel BUG?!", total_entries, cache.entry_num);
Can this happen? Isn't it a failure case?
Besides
Reviewed-by: Eric Auger <eric.au...@redhat.com>
Eric
> + return false;
> + }
> +
> + return !ret;
> +}
> +
> static int hiod_iommufd_get_cap(HostIOMMUDevice *hiod, int cap, Error **errp)
> {
> HostIOMMUDeviceCaps *caps = &hiod->caps;
> diff --git a/backends/trace-events b/backends/trace-events
> index 40811a3162..7278214ea5 100644
> --- a/backends/trace-events
> +++ b/backends/trace-events
> @@ -18,3 +18,4 @@ iommufd_backend_alloc_hwpt(int iommufd, uint32_t dev_id,
> uint32_t pt_id, uint32_
> iommufd_backend_free_id(int iommufd, uint32_t id, int ret) " iommufd=%d
> id=%d (%d)"
> iommufd_backend_set_dirty(int iommufd, uint32_t hwpt_id, bool start, int
> ret) " iommufd=%d hwpt=%u enable=%d (%d)"
> iommufd_backend_get_dirty_bitmap(int iommufd, uint32_t hwpt_id, uint64_t
> iova, uint64_t size, uint64_t page_size, int ret) " iommufd=%d hwpt=%u
> iova=0x%"PRIx64" size=0x%"PRIx64" page_size=0x%"PRIx64" (%d)"
> +iommufd_backend_invalidate_cache(int iommufd, uint32_t id, uint32_t
> data_type, uint32_t entry_len, uint32_t entry_num, uint32_t done_num,
> uint64_t data_ptr, int ret) " iommufd=%d id=%u data_type=%u entry_len=%u
> entry_num=%u done_num=%u data_ptr=0x%"PRIx64" (%d)"
