On 12/2/2025 10:12 AM, Christian König wrote:
Instead of abusing the create IOCTL to open global BO add a new
AMDGPU_GEM_OP_OPEN_GLOBAL functionality.
The new AMDGPU_GEM_OP_OPEN_GLOBAL functionality expects an enum which tells
it which global BO to open and copies the information about the BO to
userspace similar to the AMDGPU_GEM_OP_GET_GEM_CREATE_INFO operation.
The advantage is that we don't start overloading the create IOCTL with
tons of special cases and opening the global BOs doesn't requires knowing
the exact size and parameters of it in userspace any more.
Heavily WIP and only compile tested.
Signed-off-by: Christian König <[email protected]>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c | 26 ++++++++++++++++++++-----
include/uapi/drm/amdgpu_drm.h | 5 ++++-
2 files changed, 25 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
index 9b81a6677f90..9e9b94dcb699 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
@@ -968,22 +968,34 @@ int amdgpu_gem_va_ioctl(struct drm_device *dev, void
*data,
int amdgpu_gem_op_ioctl(struct drm_device *dev, void *data,
struct drm_file *filp)
{
+ struct amdgpu_fpriv *fpriv = filp->driver_priv;
struct drm_amdgpu_gem_op *args = data;
struct drm_gem_object *gobj;
struct amdgpu_vm_bo_base *base;
struct amdgpu_bo *robj;
struct drm_exec exec;
- struct amdgpu_fpriv *fpriv = filp->driver_priv;
int r;
if (args->padding)
return -EINVAL;
- gobj = drm_gem_object_lookup(filp, args->handle);
- if (!gobj)
- return -ENOENT;
+ if (args->op == AMDGPU_GEM_OP_OPEN_GLOBAL) {
+ switch (args->handle) {
+ case AMDGPU_GEM_GLOBAL_MMIO_REMAP:
+ robj = drm_to_adev(dev)->rmmio_remap.bo;
rmmio_remap.bo could be null - so robj should be checked and return error
instead.
David
+ break;
+ default:
+ return -EINVAL;
+ }
+ gobj = &robj->tbo.base;
+ drm_gem_object_get(gobj);
+ } else {
+ gobj = drm_gem_object_lookup(filp, args->handle);
+ if (!gobj)
+ return -ENOENT;
- robj = gem_to_amdgpu_bo(gobj);
+ robj = gem_to_amdgpu_bo(gobj);
+ }
drm_exec_init(&exec, DRM_EXEC_INTERRUPTIBLE_WAIT |
DRM_EXEC_IGNORE_DUPLICATES, 0);
@@ -1002,6 +1014,7 @@ int amdgpu_gem_op_ioctl(struct drm_device *dev, void
*data,
}
switch (args->op) {
+ case AMDGPU_GEM_OP_OPEN_GLOBAL:
case AMDGPU_GEM_OP_GET_GEM_CREATE_INFO: {
struct drm_amdgpu_gem_create_in info;
void __user *out = u64_to_user_ptr(args->value);
@@ -1096,6 +1109,9 @@ int amdgpu_gem_op_ioctl(struct drm_device *dev, void
*data,
r = -EINVAL;
}
+ if (!r && args->op == AMDGPU_GEM_OP_OPEN_GLOBAL)
+ r = drm_gem_handle_create(filp, gobj, &args->handle);
+
drm_gem_object_put(gobj);
return r;
out_exec:
diff --git a/include/uapi/drm/amdgpu_drm.h b/include/uapi/drm/amdgpu_drm.h
index c1336ed4ff75..6927c864a6d1 100644
--- a/include/uapi/drm/amdgpu_drm.h
+++ b/include/uapi/drm/amdgpu_drm.h
@@ -807,6 +807,9 @@ union drm_amdgpu_wait_fences {
#define AMDGPU_GEM_OP_GET_GEM_CREATE_INFO 0
#define AMDGPU_GEM_OP_SET_PLACEMENT 1
#define AMDGPU_GEM_OP_GET_MAPPING_INFO 2
+#define AMDGPU_GEM_OP_OPEN_GLOBAL 3
+
+#define AMDGPU_GEM_GLOBAL_MMIO_REMAP 0
struct drm_amdgpu_gem_vm_entry {
/* Start of mapping (in bytes) */
@@ -824,7 +827,7 @@ struct drm_amdgpu_gem_vm_entry {
/* Sets or returns a value associated with a buffer. */
struct drm_amdgpu_gem_op {
- /** GEM object handle */
+ /** GEM object handle or AMDGPU_GEM_GLOBAL_* */
__u32 handle;
/** AMDGPU_GEM_OP_* */
__u32 op;
