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XenevaOS
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#include <panthor_drm.h>
Public Attributes | |
| __u32 | flags |
| __u32 | id |
| __u64 | user_va_range |
struct drm_panthor_vm_create - Arguments passed to DRM_PANTHOR_IOCTL_VM_CREATE
| __u32 drm_panthor_vm_create::flags |
@flags: VM flags, MBZ.
| __u32 drm_panthor_vm_create::id |
@id: Returned VM ID.
| __u64 drm_panthor_vm_create::user_va_range |
@user_va_range: Size of the VA space reserved for user objects.
The kernel will pick the remaining space to map kernel-only objects to the VM (heap chunks, heap context, ring buffers, kernel synchronization objects, ...). If the space left for kernel objects is too small, kernel object allocation will fail further down the road. One can use drm_panthor_gpu_info::mmu_features to extract the total virtual address range, and chose a user_va_range that leaves some space to the kernel.
If user_va_range is zero, the kernel will pick a sensible value based on TASK_SIZE and the virtual range supported by the GPU MMU (the kernel/user split should leave enough VA space for userspace processes to support SVM, while still allowing the kernel to map some amount of kernel objects in the kernel VA range). The value chosen by the driver will be returned in @user_va_range.
User VA space always starts at 0x0, kernel VA space is always placed after the user VA range.
1.9.8