Commit e8b3b3ef53 for qemu.org

commit e8b3b3ef5381df5daa9071e9e93bbcaeb9963a4e
Author: Zhenzhong Duan <zhenzhong.duan@intel.com>
Date:   Tue Oct 20 17:19:50 2026 +0800

    backends/iommufd: Introduce iommufd_backend_alloc_faultq

    Add a new helper for IOMMU_FAULT_QUEUE_ALLOC ioctl to allocate a fault
    handling object which will be used in hwpt allocation.

    Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
    Reviewed-by: Clement Mathieu--Drif <clement.mathieu--drif@bull.com>
    Reviewed-by: Yi Liu <yi.l.liu@intel.com>
    Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
    Tested-by: Xudong Hao <xudong.hao@intel.com>
    Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
    Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
    Message-ID: <20261020091955.1607161-3-zhenzhong.duan@intel.com>

diff --git a/backends/iommufd.c b/backends/iommufd.c
index 45fd2e44c7..457b74a558 100644
--- a/backends/iommufd.c
+++ b/backends/iommufd.c
@@ -556,6 +556,27 @@ bool iommufd_backend_alloc_veventq(IOMMUFDBackend *be, uint32_t viommu_id,
     return true;
 }

+bool iommufd_backend_alloc_faultq(IOMMUFDBackend *be, uint32_t *out_fault_id,
+                                  uint32_t *out_fault_fd, Error **errp)
+{
+    int ret, fd = be->fd;
+    struct iommu_fault_alloc cmd = {
+        .size = sizeof(cmd),
+    };
+
+    ret = ioctl(fd, IOMMU_FAULT_QUEUE_ALLOC, &cmd);
+    trace_iommufd_backend_alloc_faultq(fd, cmd.out_fault_id, cmd.out_fault_fd,
+                                       ret);
+    if (ret) {
+        error_setg_errno(errp, errno, "Failed to allocate fault queue");
+        return false;
+    }
+
+    *out_fault_id = cmd.out_fault_id;
+    *out_fault_fd = cmd.out_fault_fd;
+    return true;
+}
+
 bool iommufd_backend_alloc_hw_queue(IOMMUFDBackend *be, uint32_t viommu_id,
                                     uint32_t queue_type, uint32_t index,
                                     uint64_t addr, uint64_t length,
diff --git a/backends/trace-events b/backends/trace-events
index 9b7b9b7d68..b1c1d89dd8 100644
--- a/backends/trace-events
+++ b/backends/trace-events
@@ -17,6 +17,7 @@ iommufd_backend_unmap_dma_non_exist(int iommufd, uint32_t ioas, uint64_t iova, u
 iommufd_backend_unmap_dma(int iommufd, uint32_t ioas, uint64_t iova, uint64_t size, int ret) " iommufd=%d ioas=%d iova=0x%"PRIx64" size=0x%"PRIx64" (%d)"
 iommufd_backend_alloc_ioas(int iommufd, uint32_t ioas) " iommufd=%d ioas=%d"
 iommufd_backend_alloc_hwpt(int iommufd, uint32_t dev_id, uint32_t pt_id, uint32_t flags, uint32_t hwpt_type, uint32_t len, uint64_t data_ptr, uint32_t out_hwpt_id, int ret) " iommufd=%d dev_id=%u pt_id=%u flags=0x%x hwpt_type=%u len=%u data_ptr=0x%"PRIx64" out_hwpt=%u (%d)"
+iommufd_backend_alloc_faultq(int iommufd, uint32_t fault_id, uint32_t fault_fd, int ret) " iommufd=%d fault_id=%u fault_fd=%u (%d)"
 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 flags, uint64_t page_size, int ret) " iommufd=%d hwpt=%u iova=0x%"PRIx64" size=0x%"PRIx64" flags=0x%"PRIx64" page_size=0x%"PRIx64" (%d)"
diff --git a/include/system/iommufd.h b/include/system/iommufd.h
index 17bf1a3727..36b34b4899 100644
--- a/include/system/iommufd.h
+++ b/include/system/iommufd.h
@@ -106,6 +106,9 @@ bool iommufd_backend_alloc_veventq(IOMMUFDBackend *be, uint32_t viommu_id,
                                    uint32_t *out_veventq_id,
                                    uint32_t *out_veventq_fd, Error **errp);

+bool iommufd_backend_alloc_faultq(IOMMUFDBackend *be, uint32_t *out_fault_id,
+                                  uint32_t *out_fault_fd, Error **errp);
+
 bool iommufd_backend_alloc_hw_queue(IOMMUFDBackend *be, uint32_t viommu_id,
                                     uint32_t queue_type, uint32_t index,
                                     uint64_t addr, uint64_t length,