On Tue, Mar 4, 2025 9:09 AM Cavitt, Jonathan wrote
> Add support for userspace to request a list of observed failed pagefaults from
> a specified VM.
>
> v2:
> - Only allow querying of failed pagefaults (Matt Brost)
>
> v3:
> - Remove unnecessary size parameter from helper function, as it
> is a property of the arguments. (jcavitt)
> - Remove unnecessary copy_from_user (Jainxun)
> - Set address_precision to 1 (Jainxun)
> - Report max size instead of dynamic size for memory allocation
> purposes. Total memory usage is reported separately.
>
> v4:
> - Return int from xe_vm_get_property_size (Shuicheng)
> - Fix memory leak (Shuicheng)
> - Remove unnecessary size variable (jcavitt)
>
> Signed-off-by: Jonathan Cavitt <jonathan.cav...@intel.com>
> Suggested-by: Matthew Brost <matthew.br...@intel.com>
> CC: Jainxun Zhang <jianxun.zh...@intel.com>
> CC: Shuicheng Lin <shuicheng....@intel.com>
> ---
> drivers/gpu/drm/xe/xe_device.c | 3 ++
> drivers/gpu/drm/xe/xe_vm.c | 75
> ++++++++++++++++++++++++++++++++++
> drivers/gpu/drm/xe/xe_vm.h | 2 +
> 3 files changed, 80 insertions(+)
>
> diff --git a/drivers/gpu/drm/xe/xe_device.c b/drivers/gpu/drm/xe/xe_device.c
> index 9454b51f7ad8..43accae152ff 100644
> --- a/drivers/gpu/drm/xe/xe_device.c
> +++ b/drivers/gpu/drm/xe/xe_device.c
> @@ -193,6 +193,9 @@ static const struct drm_ioctl_desc xe_ioctls[] = {
> DRM_IOCTL_DEF_DRV(XE_WAIT_USER_FENCE,
> xe_wait_user_fence_ioctl,
> DRM_RENDER_ALLOW),
> DRM_IOCTL_DEF_DRV(XE_OBSERVATION, xe_observation_ioctl,
> DRM_RENDER_ALLOW),
> + DRM_IOCTL_DEF_DRV(XE_VM_GET_PROPERTY,
> xe_vm_get_property_ioctl,
> + DRM_RENDER_ALLOW),
> +
> };
>
> static long xe_drm_ioctl(struct file *file, unsigned int cmd, unsigned long
> arg)
> diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c index
> 6211b971bbbd..1e78103fb0f6 100644
> --- a/drivers/gpu/drm/xe/xe_vm.c
> +++ b/drivers/gpu/drm/xe/xe_vm.c
> @@ -3234,6 +3234,81 @@ int xe_vm_bind_ioctl(struct drm_device *dev,
> void *data, struct drm_file *file)
> return err;
> }
>
> +static int xe_vm_get_property_size(struct xe_vm *vm, u32 property) {
> + switch (property) {
> + case DRM_XE_VM_GET_PROPERTY_FAULTS:
> + return MAX_PFS * sizeof(struct drm_xe_pf);
> + default:
> + return -EINVAL;
> + }
> +}
> +
> +static int fill_property_pfs(struct xe_vm *vm,
> + struct drm_xe_vm_get_property *args) {
> + struct drm_xe_pf __user *usr_ptr = u64_to_user_ptr(args->ptr);
> + struct drm_xe_pf *fault_list;
> + struct drm_xe_pf *fault;
> + struct xe_vm_pf_entry *entry;
> + int ret, i = 0;
> +
> + fault_list = kzalloc(args->size, GFP_KERNEL);
> + if (!fault_list)
> + return -ENOMEM;
> +
> + spin_lock(&vm->pfs.lock);
> + list_for_each_entry(entry, &vm->pfs.list, list) {
> + struct xe_pagefault *pf = entry->pf;
> +
> + fault = &fault_list[i++];
> + fault->address = pf->page_addr;
> + fault->address_type = pf->address_type;
> + fault->address_precision = 1;
> + }
> + args->value = vm->pfs.len;
It should be args->size instead of "args->value" ?
Shuicheng
> + spin_unlock(&vm->pfs.lock);
> +
> + ret = copy_to_user(usr_ptr, &fault_list, args->size);
It should be fault_list instead of "&fault_list" ?
Shuicheng
> + kfree(fault_list);
> +
> + return ret ? -EFAULT : 0;
> +}
> +
> +int xe_vm_get_property_ioctl(struct drm_device *drm, void *data,
> + struct drm_file *file)
> +{
> + struct xe_device *xe = to_xe_device(drm);
> + struct xe_file *xef = to_xe_file(file);
> + struct drm_xe_vm_get_property *args = data;
> + struct xe_vm *vm;
> + int size;
> +
> + if (XE_IOCTL_DBG(xe, args->reserved[0] || args->reserved[1]))
> + return -EINVAL;
> +
> + vm = xe_vm_lookup(xef, args->vm_id);
> + if (XE_IOCTL_DBG(xe, !vm))
> + return -ENOENT;
This vm need be released with xe_vm_put(vm) at the end of the function.
Shuicheng
> +
> + size = xe_vm_get_property_size(vm, args->property);
> + if (size < 0) {
> + return size;
> + } else if (args->size != size) {
> + if (args->size)
> + return -EINVAL;
> + args->size = size;
> + return 0;
> + }
> +
> + switch (args->property) {
> + case DRM_XE_VM_GET_PROPERTY_FAULTS:
> + return fill_property_pfs(vm, args);
> + default:
> + return -EINVAL;
> + }
> +}
> +
> /**
> * xe_vm_bind_kernel_bo - bind a kernel BO to a VM
> * @vm: VM to bind the BO to
> diff --git a/drivers/gpu/drm/xe/xe_vm.h b/drivers/gpu/drm/xe/xe_vm.h index
> 4d94ab5c8ea4..bf6604465aa3 100644
> --- a/drivers/gpu/drm/xe/xe_vm.h
> +++ b/drivers/gpu/drm/xe/xe_vm.h
> @@ -184,6 +184,8 @@ int xe_vm_destroy_ioctl(struct drm_device *dev, void
> *data,
> struct drm_file *file);
> int xe_vm_bind_ioctl(struct drm_device *dev, void *data,
> struct drm_file *file);
> +int xe_vm_get_property_ioctl(struct drm_device *dev, void *data,
> + struct drm_file *file);
>
> void xe_vm_close_and_put(struct xe_vm *vm);
>
> --
> 2.43.0
