[Intel-xe] [PATCH v2 01/27] drm/xe: Allow num_binds == 0 in VM bind IOCTL

[Dafna Hirschfeld]

On 06.11.2023 21:25, Matthew Brost wrote:
>The idea being out-syncs can signal indicating all previous operations
>on the bind queue are complete. An example use case of this would be
>support for implementing vkQueueWaitForIdle easily.
>
>Signed-off-by: Matthew Brost <matthew.brost at intel.com>
>---
> drivers/gpu/drm/xe/xe_vm.c | 30 ++++++++++++++++++------------
> 1 file changed, 18 insertions(+), 12 deletions(-)
>
>diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c
>index d26c90f0d702..403444ff3856 100644
>--- a/drivers/gpu/drm/xe/xe_vm.c
>+++ b/drivers/gpu/drm/xe/xe_vm.c
>@@ -2850,7 +2850,6 @@ static int vm_bind_ioctl_check_args(struct xe_device *xe,
> 	int i;
>
> 	if (XE_IOCTL_DBG(xe, args->extensions) ||
>-	    XE_IOCTL_DBG(xe, !args->num_binds) ||
> 	    XE_IOCTL_DBG(xe, args->num_binds > MAX_BINDS))
> 		return -EINVAL;
>
>@@ -2977,7 +2976,7 @@ int xe_vm_bind_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
> 			goto put_exec_queue;
> 		}
>
>-		if (XE_IOCTL_DBG(xe, async !=
>+		if (XE_IOCTL_DBG(xe, args->num_binds && async !=
> 				 !!(q->flags & EXEC_QUEUE_FLAG_VM_ASYNC))) {
> 			err = -EINVAL;
> 			goto put_exec_queue;
>@@ -2991,7 +2990,7 @@ int xe_vm_bind_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
> 	}
>
> 	if (!args->exec_queue_id) {
>-		if (XE_IOCTL_DBG(xe, async !=
>+		if (XE_IOCTL_DBG(xe, args->num_binds && async !=
> 				 !!(vm->flags & XE_VM_FLAG_ASYNC_DEFAULT))) {
> 			err = -EINVAL;
> 			goto put_vm;
>@@ -3028,16 +3027,18 @@ int xe_vm_bind_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
> 		}
> 	}
>
>-	bos = kzalloc(sizeof(*bos) * args->num_binds, GFP_KERNEL);
>-	if (!bos) {
>-		err = -ENOMEM;
>-		goto release_vm_lock;
>-	}
>+	if (args->num_binds) {
>+		bos = kzalloc(sizeof(*bos) * args->num_binds, GFP_KERNEL);
>+		if (!bos) {
>+			err = -ENOMEM;
>+			goto release_vm_lock;
>+		}
>
>-	ops = kzalloc(sizeof(*ops) * args->num_binds, GFP_KERNEL);
>-	if (!ops) {
>-		err = -ENOMEM;
>-		goto release_vm_lock;
>+		ops = kzalloc(sizeof(*ops) * args->num_binds, GFP_KERNEL);
>+		if (!ops) {
>+			err = -ENOMEM;
>+			goto release_vm_lock;
>+		}
> 	}
>
> 	for (i = 0; i < args->num_binds; ++i) {
>@@ -3092,6 +3093,11 @@ int xe_vm_bind_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
> 			goto free_syncs;
> 	}
>
>+	if (!args->num_binds) {
>+		err = -ENODATA;
>+		goto free_syncs;
if args->num_binds = 0 is valid, then it might be confusing to indicate it with err = -ENODATA,
Also , it is invalid if both args->num_binds and args->num_syncs are 0 right? if so maybe
add XE_IOCTL_DBG for that,

Thanks,
Dafna

>+	}
>+
> 	for (i = 0; i < args->num_binds; ++i) {
> 		u64 range = bind_ops[i].range;
> 		u64 addr = bind_ops[i].addr;
>-- 
>2.34.1
>