Danilo Krummrich
2023-Oct-08 23:32 UTC
[Nouveau] [PATCH drm-misc-next v6 3/6] drm/gpuvm: add an abstraction for a VM / BO combination
Add an abstraction layer between the drm_gpuva mappings of a particular
drm_gem_object and this GEM object itself. The abstraction represents a
combination of a drm_gem_object and drm_gpuvm. The drm_gem_object holds
a list of drm_gpuvm_bo structures (the structure representing this
abstraction), while each drm_gpuvm_bo contains list of mappings of this
GEM object.
This has multiple advantages:
1) We can use the drm_gpuvm_bo structure to attach it to various lists
of the drm_gpuvm. This is useful for tracking external and evicted
objects per VM, which is introduced in subsequent patches.
2) Finding mappings of a certain drm_gem_object mapped in a certain
drm_gpuvm becomes much cheaper.
3) Drivers can derive and extend the structure to easily represent
driver specific states of a BO for a certain GPUVM.
The idea of this abstraction was taken from amdgpu, hence the credit for
this idea goes to the developers of amdgpu.
Cc: Christian K?nig <christian.koenig at amd.com>
Signed-off-by: Danilo Krummrich <dakr at redhat.com>
---
drivers/gpu/drm/drm_gpuvm.c | 332 +++++++++++++++++++++----
drivers/gpu/drm/nouveau/nouveau_uvmm.c | 64 +++--
include/drm/drm_gem.h | 32 +--
include/drm/drm_gpuvm.h | 177 ++++++++++++-
4 files changed, 521 insertions(+), 84 deletions(-)
diff --git a/drivers/gpu/drm/drm_gpuvm.c b/drivers/gpu/drm/drm_gpuvm.c
index 6368dfdbe9dd..28282283ddaf 100644
--- a/drivers/gpu/drm/drm_gpuvm.c
+++ b/drivers/gpu/drm/drm_gpuvm.c
@@ -70,6 +70,18 @@
* &drm_gem_object, such as the &drm_gem_object containing the root
page table,
* but it can also be a 'dummy' object, which can be allocated with
* drm_gpuvm_root_object_alloc().
+ *
+ * In order to connect a struct drm_gpuva its backing &drm_gem_object each
+ * &drm_gem_object maintains a list of &drm_gpuvm_bo structures, and
each
+ * &drm_gpuvm_bo contains a list of &&drm_gpuva structures.
+ *
+ * A &drm_gpuvm_bo is an abstraction that represents a combination of a
+ * &drm_gpuvm and a &drm_gem_object. Every such combination should be
unique.
+ * This is ensured by the API through drm_gpuvm_bo_obtain() and
+ * drm_gpuvm_bo_obtain_prealloc() which first look into the corresponding
+ * &drm_gem_object list of &drm_gpuvm_bos for an existing instance of
this
+ * particular combination. If not existent a new instance is created and linked
+ * to the &drm_gem_object.
*/
/**
@@ -395,21 +407,28 @@
/**
* DOC: Locking
*
- * Generally, the GPU VA manager does not take care of locking itself, it is
- * the drivers responsibility to take care about locking. Drivers might want to
- * protect the following operations: inserting, removing and iterating
- * &drm_gpuva objects as well as generating all kinds of operations, such
as
- * split / merge or prefetch.
- *
- * The GPU VA manager also does not take care of the locking of the backing
- * &drm_gem_object buffers GPU VA lists by itself; drivers are responsible
to
- * enforce mutual exclusion using either the GEMs dma_resv lock or
alternatively
- * a driver specific external lock. For the latter see also
- * drm_gem_gpuva_set_lock().
- *
- * However, the GPU VA manager contains lockdep checks to ensure callers of its
- * API hold the corresponding lock whenever the &drm_gem_objects GPU VA
list is
- * accessed by functions such as drm_gpuva_link() or drm_gpuva_unlink().
+ * In terms of managing &drm_gpuva entries DRM GPUVM does not take care of
+ * locking itself, it is the drivers responsibility to take care about locking.
+ * Drivers might want to protect the following operations: inserting, removing
+ * and iterating &drm_gpuva objects as well as generating all kinds of
+ * operations, such as split / merge or prefetch.
+ *
+ * DRM GPUVM also does not take care of the locking of the backing
+ * &drm_gem_object buffers GPU VA lists and &drm_gpuvm_bo abstractions
by
+ * itself; drivers are responsible to enforce mutual exclusion using either the
+ * GEMs dma_resv lock or alternatively a driver specific external lock. For the
+ * latter see also drm_gem_gpuva_set_lock().
+ *
+ * However, DRM GPUVM contains lockdep checks to ensure callers of its API hold
+ * the corresponding lock whenever the &drm_gem_objects GPU VA list is
accessed
+ * by functions such as drm_gpuva_link() or drm_gpuva_unlink(), but also
+ * drm_gpuvm_bo_obtain() and drm_gpuvm_bo_put().
+ *
+ * The latter is required since on creation and destruction of a
&drm_gpuvm_bo
+ * the &drm_gpuvm_bo is attached / removed from the &drm_gem_objects
gpuva list.
+ * Subsequent calls to drm_gpuvm_bo_obtain() for the same &drm_gpuvm and
+ * &drm_gem_object must be able to observe previous creations and
destructions
+ * of &drm_gpuvm_bos in order to keep instances unique.
*/
/**
@@ -439,6 +458,7 @@
* {
* struct drm_gpuva_ops *ops;
* struct drm_gpuva_op *op
+ * struct drm_gpuvm_bo *vm_bo;
*
* driver_lock_va_space();
* ops = drm_gpuvm_sm_map_ops_create(gpuvm, addr, range,
@@ -446,6 +466,10 @@
* if (IS_ERR(ops))
* return PTR_ERR(ops);
*
+ * vm_bo = drm_gpuvm_bo_obtain(gpuvm, obj);
+ * if (IS_ERR(vm_bo))
+ * return PTR_ERR(vm_bo);
+ *
* drm_gpuva_for_each_op(op, ops) {
* struct drm_gpuva *va;
*
@@ -458,7 +482,7 @@
*
* driver_vm_map();
* drm_gpuva_map(gpuvm, va, &op->map);
- * drm_gpuva_link(va);
+ * drm_gpuva_link(va, vm_bo);
*
* break;
* case DRM_GPUVA_OP_REMAP: {
@@ -485,11 +509,11 @@
* driver_vm_remap();
* drm_gpuva_remap(prev, next, &op->remap);
*
- * drm_gpuva_unlink(va);
* if (prev)
- * drm_gpuva_link(prev);
+ * drm_gpuva_link(prev, va->vm_bo);
* if (next)
- * drm_gpuva_link(next);
+ * drm_gpuva_link(next, va->vm_bo);
+ * drm_gpuva_unlink(va);
*
* break;
* }
@@ -505,6 +529,7 @@
* break;
* }
* }
+ * drm_gpuvm_bo_put(vm_bo);
* driver_unlock_va_space();
*
* return 0;
@@ -514,6 +539,7 @@
*
* struct driver_context {
* struct drm_gpuvm *gpuvm;
+ * struct drm_gpuvm_bo *vm_bo;
* struct drm_gpuva *new_va;
* struct drm_gpuva *prev_va;
* struct drm_gpuva *next_va;
@@ -534,6 +560,7 @@
* struct drm_gem_object *obj, u64 offset)
* {
* struct driver_context ctx;
+ * struct drm_gpuvm_bo *vm_bo;
* struct drm_gpuva_ops *ops;
* struct drm_gpuva_op *op;
* int ret = 0;
@@ -543,16 +570,23 @@
* ctx.new_va = kzalloc(sizeof(*ctx.new_va), GFP_KERNEL);
* ctx.prev_va = kzalloc(sizeof(*ctx.prev_va), GFP_KERNEL);
* ctx.next_va = kzalloc(sizeof(*ctx.next_va), GFP_KERNEL);
- * if (!ctx.new_va || !ctx.prev_va || !ctx.next_va) {
+ * ctx.vm_bo = drm_gpuvm_bo_create(gpuvm, obj);
+ * if (!ctx.new_va || !ctx.prev_va || !ctx.next_va || !vm_bo) {
* ret = -ENOMEM;
* goto out;
* }
*
+ * // Typically protected with a driver specific GEM gpuva lock
+ * // used in the fence signaling path for drm_gpuva_link() and
+ * // drm_gpuva_unlink(), hence pre-allocate.
+ * ctx.vm_bo = drm_gpuvm_bo_obtain_prealloc(ctx.vm_bo);
+ *
* driver_lock_va_space();
* ret = drm_gpuvm_sm_map(gpuvm, &ctx, addr, range, obj, offset);
* driver_unlock_va_space();
*
* out:
+ * drm_gpuvm_bo_put(ctx.vm_bo);
* kfree(ctx.new_va);
* kfree(ctx.prev_va);
* kfree(ctx.next_va);
@@ -565,7 +599,7 @@
*
* drm_gpuva_map(ctx->vm, ctx->new_va, &op->map);
*
- * drm_gpuva_link(ctx->new_va);
+ * drm_gpuva_link(ctx->new_va, ctx->vm_bo);
*
* // prevent the new GPUVA from being freed in
* // driver_mapping_create()
@@ -577,22 +611,23 @@
* int driver_gpuva_remap(struct drm_gpuva_op *op, void *__ctx)
* {
* struct driver_context *ctx = __ctx;
+ * struct drm_gpuva *va = op->remap.unmap->va;
*
* drm_gpuva_remap(ctx->prev_va, ctx->next_va, &op->remap);
*
- * drm_gpuva_unlink(op->remap.unmap->va);
- * kfree(op->remap.unmap->va);
- *
* if (op->remap.prev) {
- * drm_gpuva_link(ctx->prev_va);
+ * drm_gpuva_link(ctx->prev_va, va->vm_bo);
* ctx->prev_va = NULL;
* }
*
* if (op->remap.next) {
- * drm_gpuva_link(ctx->next_va);
+ * drm_gpuva_link(ctx->next_va, va->vm_bo);
* ctx->next_va = NULL;
* }
*
+ * drm_gpuva_unlink(va);
+ * kfree(va);
+ *
* return 0;
* }
*
@@ -771,6 +806,194 @@ drm_gpuvm_destroy(struct drm_gpuvm *gpuvm)
}
EXPORT_SYMBOL_GPL(drm_gpuvm_destroy);
+/**
+ * drm_gpuvm_bo_create() - create a new instance of struct drm_gpuvm_bo
+ * @gpuvm: The &drm_gpuvm the @obj is mapped in.
+ * @obj: The &drm_gem_object being mapped in the @gpuvm.
+ *
+ * If provided by the driver, this function uses the &drm_gpuvm_ops
+ * vm_bo_alloc() callback to allocate.
+ *
+ * Returns: a pointer to the &drm_gpuvm_bo on success, NULL on failure
+ */
+struct drm_gpuvm_bo *
+drm_gpuvm_bo_create(struct drm_gpuvm *gpuvm,
+ struct drm_gem_object *obj)
+{
+ const struct drm_gpuvm_ops *ops = gpuvm->ops;
+ struct drm_gpuvm_bo *vm_bo;
+
+ if (ops && ops->vm_bo_alloc)
+ vm_bo = ops->vm_bo_alloc();
+ else
+ vm_bo = kzalloc(sizeof(*vm_bo), GFP_KERNEL);
+
+ if (unlikely(!vm_bo))
+ return NULL;
+
+ vm_bo->vm = gpuvm;
+ vm_bo->obj = obj;
+
+ kref_init(&vm_bo->kref);
+ INIT_LIST_HEAD(&vm_bo->list.gpuva);
+ INIT_LIST_HEAD(&vm_bo->list.entry.gem);
+
+ drm_gem_object_get(obj);
+
+ return vm_bo;
+}
+EXPORT_SYMBOL_GPL(drm_gpuvm_bo_create);
+
+static void
+drm_gpuvm_bo_destroy(struct kref *kref)
+{
+ struct drm_gpuvm_bo *vm_bo = container_of(kref, struct drm_gpuvm_bo,
+ kref);
+ struct drm_gpuvm *gpuvm = vm_bo->vm;
+ const struct drm_gpuvm_ops *ops = gpuvm->ops;
+ struct drm_gem_object *obj = vm_bo->obj;
+ bool lock = !drm_gpuvm_resv_protected(gpuvm);
+
+ drm_gem_gpuva_assert_lock_held(obj);
+ if (!lock)
+ drm_gpuvm_resv_assert_held(gpuvm);
+
+ list_del(&vm_bo->list.entry.gem);
+
+ drm_gem_object_put(obj);
+
+ if (ops && ops->vm_bo_free)
+ ops->vm_bo_free(vm_bo);
+ else
+ kfree(vm_bo);
+}
+
+/**
+ * drm_gpuvm_bo_put() - drop a struct drm_gpuvm_bo reference
+ * @vm_bo: the &drm_gpuvm_bo to release the reference of
+ *
+ * This releases a reference to @vm_bo.
+ *
+ * If the reference count drops to zero, the &gpuvm_bo is destroyed, which
+ * includes removing it from the GEMs gpuva list. Hence, if a call to this
+ * function can potentially let the reference count to zero the caller must
+ * hold the dma-resv or driver specific GEM gpuva lock.
+ */
+void
+drm_gpuvm_bo_put(struct drm_gpuvm_bo *vm_bo)
+{
+ if (vm_bo)
+ kref_put(&vm_bo->kref, drm_gpuvm_bo_destroy);
+}
+EXPORT_SYMBOL_GPL(drm_gpuvm_bo_put);
+
+static struct drm_gpuvm_bo *
+__drm_gpuvm_bo_find(struct drm_gpuvm *gpuvm,
+ struct drm_gem_object *obj)
+{
+ struct drm_gpuvm_bo *vm_bo;
+
+ drm_gem_gpuva_assert_lock_held(obj);
+
+ drm_gem_for_each_gpuvm_bo(vm_bo, obj)
+ if (vm_bo->vm == gpuvm)
+ return vm_bo;
+
+ return NULL;
+}
+
+/**
+ * drm_gpuvm_bo_find() - find the &drm_gpuvm_bo for the given
+ * &drm_gpuvm and &drm_gem_object
+ * @gpuvm: The &drm_gpuvm the @obj is mapped in.
+ * @obj: The &drm_gem_object being mapped in the @gpuvm.
+ *
+ * Find the &drm_gpuvm_bo representing the combination of the given
+ * &drm_gpuvm and &drm_gem_object. If found, increases the reference
+ * count of the &drm_gpuvm_bo accordingly.
+ *
+ * Returns: a pointer to the &drm_gpuvm_bo on success, NULL on failure
+ */
+struct drm_gpuvm_bo *
+drm_gpuvm_bo_find(struct drm_gpuvm *gpuvm,
+ struct drm_gem_object *obj)
+{
+ struct drm_gpuvm_bo *vm_bo = __drm_gpuvm_bo_find(gpuvm, obj);
+
+ return vm_bo ? drm_gpuvm_bo_get(vm_bo) : NULL;
+}
+EXPORT_SYMBOL_GPL(drm_gpuvm_bo_find);
+
+/**
+ * drm_gpuvm_bo_obtain() - obtains and instance of the &drm_gpuvm_bo for
the
+ * given &drm_gpuvm and &drm_gem_object
+ * @gpuvm: The &drm_gpuvm the @obj is mapped in.
+ * @obj: The &drm_gem_object being mapped in the @gpuvm.
+ *
+ * Find the &drm_gpuvm_bo representing the combination of the given
+ * &drm_gpuvm and &drm_gem_object. If found, increases the reference
+ * count of the &drm_gpuvm_bo accordingly. If not found, allocates a new
+ * &drm_gpuvm_bo.
+ *
+ * A new &drm_gpuvm_bo is added to the GEMs gpuva list.
+ *
+ * Returns: a pointer to the &drm_gpuvm_bo on success, an ERR_PTR on
failure
+ */
+struct drm_gpuvm_bo *
+drm_gpuvm_bo_obtain(struct drm_gpuvm *gpuvm,
+ struct drm_gem_object *obj)
+{
+ struct drm_gpuvm_bo *vm_bo;
+
+ vm_bo = drm_gpuvm_bo_find(gpuvm, obj);
+ if (vm_bo)
+ return vm_bo;
+
+ vm_bo = drm_gpuvm_bo_create(gpuvm, obj);
+ if (!vm_bo)
+ return ERR_PTR(-ENOMEM);
+
+ list_add_tail(&vm_bo->list.entry.gem, &obj->gpuva.list);
+
+ return vm_bo;
+}
+EXPORT_SYMBOL_GPL(drm_gpuvm_bo_obtain);
+
+/**
+ * drm_gpuvm_bo_obtain_prealloc() - obtains and instance of the
&drm_gpuvm_bo
+ * for the given &drm_gpuvm and &drm_gem_object
+ * @__vm_bo: A pre-allocated struct drm_gpuvm_bo.
+ *
+ * Find the &drm_gpuvm_bo representing the combination of the given
+ * &drm_gpuvm and &drm_gem_object. If found, increases the reference
+ * count of the found &drm_gpuvm_bo accordingly, while the @__vm_bo
reference
+ * count is decreased. If not found @__vm_bo is returned without further
+ * increase of the reference count.
+ *
+ * A new &drm_gpuvm_bo is added to the GEMs gpuva list.
+ *
+ * Returns: a pointer to the found &drm_gpuvm_bo or @__vm_bo if no existing
+ * &drm_gpuvm_bo was found
+ */
+struct drm_gpuvm_bo *
+drm_gpuvm_bo_obtain_prealloc(struct drm_gpuvm_bo *__vm_bo)
+{
+ struct drm_gpuvm *gpuvm = __vm_bo->vm;
+ struct drm_gem_object *obj = __vm_bo->obj;
+ struct drm_gpuvm_bo *vm_bo;
+
+ vm_bo = drm_gpuvm_bo_find(gpuvm, obj);
+ if (vm_bo) {
+ drm_gpuvm_bo_put(__vm_bo);
+ return vm_bo;
+ }
+
+ list_add_tail(&__vm_bo->list.entry.gem, &obj->gpuva.list);
+
+ return __vm_bo;
+}
+EXPORT_SYMBOL_GPL(drm_gpuvm_bo_obtain_prealloc);
+
static int
__drm_gpuva_insert(struct drm_gpuvm *gpuvm,
struct drm_gpuva *va)
@@ -860,24 +1083,33 @@ EXPORT_SYMBOL_GPL(drm_gpuva_remove);
/**
* drm_gpuva_link() - link a &drm_gpuva
* @va: the &drm_gpuva to link
+ * @vm_bo: the &drm_gpuvm_bo to add the &drm_gpuva to
*
- * This adds the given &va to the GPU VA list of the &drm_gem_object it
is
- * associated with.
+ * This adds the given &va to the GPU VA list of the &drm_gpuvm_bo and
the
+ * &drm_gpuvm_bo to the &drm_gem_object it is associated with.
+ *
+ * For every &drm_gpuva entry added to the &drm_gpuvm_bo an additional
+ * reference of the latter is taken.
*
* This function expects the caller to protect the GEM's GPUVA list against
- * concurrent access using the GEMs dma_resv lock.
+ * concurrent access using either the GEMs dma_resv lock or a driver specific
+ * lock set through drm_gem_gpuva_set_lock().
*/
void
-drm_gpuva_link(struct drm_gpuva *va)
+drm_gpuva_link(struct drm_gpuva *va, struct drm_gpuvm_bo *vm_bo)
{
struct drm_gem_object *obj = va->gem.obj;
if (unlikely(!obj))
return;
+ WARN_ON(obj != vm_bo->obj);
drm_gem_gpuva_assert_lock_held(obj);
- list_add_tail(&va->gem.entry, &obj->gpuva.list);
+ drm_gpuvm_bo_get(vm_bo);
+
+ va->vm_bo = vm_bo;
+ list_add_tail(&va->gem.entry, &vm_bo->list.gpuva);
}
EXPORT_SYMBOL_GPL(drm_gpuva_link);
@@ -888,13 +1120,22 @@ EXPORT_SYMBOL_GPL(drm_gpuva_link);
* This removes the given &va from the GPU VA list of the
&drm_gem_object it is
* associated with.
*
+ * This removes the given &va from the GPU VA list of the &drm_gpuvm_bo
and
+ * the &drm_gpuvm_bo from the &drm_gem_object it is associated with in
case
+ * this call unlinks the last &drm_gpuva from the &drm_gpuvm_bo.
+ *
+ * For every &drm_gpuva entry removed from the &drm_gpuvm_bo a
reference of
+ * the latter is dropped.
+ *
* This function expects the caller to protect the GEM's GPUVA list against
- * concurrent access using the GEMs dma_resv lock.
+ * concurrent access using either the GEMs dma_resv lock or a driver specific
+ * lock set through drm_gem_gpuva_set_lock().
*/
void
drm_gpuva_unlink(struct drm_gpuva *va)
{
struct drm_gem_object *obj = va->gem.obj;
+ struct drm_gpuvm_bo *vm_bo = va->vm_bo;
if (unlikely(!obj))
return;
@@ -902,6 +1143,9 @@ drm_gpuva_unlink(struct drm_gpuva *va)
drm_gem_gpuva_assert_lock_held(obj);
list_del_init(&va->gem.entry);
+ va->vm_bo = NULL;
+
+ drm_gpuvm_bo_put(vm_bo);
}
EXPORT_SYMBOL_GPL(drm_gpuva_unlink);
@@ -1046,10 +1290,10 @@ drm_gpuva_remap(struct drm_gpuva *prev,
struct drm_gpuva *next,
struct drm_gpuva_op_remap *op)
{
- struct drm_gpuva *curr = op->unmap->va;
- struct drm_gpuvm *gpuvm = curr->vm;
+ struct drm_gpuva *va = op->unmap->va;
+ struct drm_gpuvm *gpuvm = va->vm;
- drm_gpuva_remove(curr);
+ drm_gpuva_remove(va);
if (op->prev) {
drm_gpuva_init_from_op(prev, op->prev);
@@ -1693,9 +1937,8 @@ drm_gpuvm_prefetch_ops_create(struct drm_gpuvm *gpuvm,
EXPORT_SYMBOL_GPL(drm_gpuvm_prefetch_ops_create);
/**
- * drm_gpuvm_gem_unmap_ops_create() - creates the &drm_gpuva_ops to unmap a
GEM
- * @gpuvm: the &drm_gpuvm representing the GPU VA space
- * @obj: the &drm_gem_object to unmap
+ * drm_gpuvm_bo_unmap_ops_create() - creates the &drm_gpuva_ops to unmap a
GEM
+ * @vm_bo: the &drm_gpuvm_bo abstraction
*
* This function creates a list of operations to perform unmapping for every
* GPUVA attached to a GEM.
@@ -1712,15 +1955,14 @@ EXPORT_SYMBOL_GPL(drm_gpuvm_prefetch_ops_create);
* Returns: a pointer to the &drm_gpuva_ops on success, an ERR_PTR on
failure
*/
struct drm_gpuva_ops *
-drm_gpuvm_gem_unmap_ops_create(struct drm_gpuvm *gpuvm,
- struct drm_gem_object *obj)
+drm_gpuvm_bo_unmap_ops_create(struct drm_gpuvm_bo *vm_bo)
{
struct drm_gpuva_ops *ops;
struct drm_gpuva_op *op;
struct drm_gpuva *va;
int ret;
- drm_gem_gpuva_assert_lock_held(obj);
+ drm_gem_gpuva_assert_lock_held(vm_bo->obj);
ops = kzalloc(sizeof(*ops), GFP_KERNEL);
if (!ops)
@@ -1728,8 +1970,8 @@ drm_gpuvm_gem_unmap_ops_create(struct drm_gpuvm *gpuvm,
INIT_LIST_HEAD(&ops->list);
- drm_gem_for_each_gpuva(va, obj) {
- op = gpuva_op_alloc(gpuvm);
+ drm_gpuvm_bo_for_each_va(va, vm_bo) {
+ op = gpuva_op_alloc(vm_bo->vm);
if (!op) {
ret = -ENOMEM;
goto err_free_ops;
@@ -1743,10 +1985,10 @@ drm_gpuvm_gem_unmap_ops_create(struct drm_gpuvm *gpuvm,
return ops;
err_free_ops:
- drm_gpuva_ops_free(gpuvm, ops);
+ drm_gpuva_ops_free(vm_bo->vm, ops);
return ERR_PTR(ret);
}
-EXPORT_SYMBOL_GPL(drm_gpuvm_gem_unmap_ops_create);
+EXPORT_SYMBOL_GPL(drm_gpuvm_bo_unmap_ops_create);
/**
* drm_gpuva_ops_free() - free the given &drm_gpuva_ops
diff --git a/drivers/gpu/drm/nouveau/nouveau_uvmm.c
b/drivers/gpu/drm/nouveau/nouveau_uvmm.c
index 93ad2ba7ec8b..4e46f850e65f 100644
--- a/drivers/gpu/drm/nouveau/nouveau_uvmm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_uvmm.c
@@ -62,6 +62,8 @@ struct bind_job_op {
enum vm_bind_op op;
u32 flags;
+ struct drm_gpuvm_bo *vm_bo;
+
struct {
u64 addr;
u64 range;
@@ -1113,22 +1115,28 @@ bind_validate_region(struct nouveau_job *job)
}
static void
-bind_link_gpuvas(struct drm_gpuva_ops *ops, struct nouveau_uvma_prealloc *new)
+bind_link_gpuvas(struct bind_job_op *bop)
{
+ struct nouveau_uvma_prealloc *new = &bop->new;
+ struct drm_gpuvm_bo *vm_bo = bop->vm_bo;
+ struct drm_gpuva_ops *ops = bop->ops;
struct drm_gpuva_op *op;
drm_gpuva_for_each_op(op, ops) {
switch (op->op) {
case DRM_GPUVA_OP_MAP:
- drm_gpuva_link(&new->map->va);
+ drm_gpuva_link(&new->map->va, vm_bo);
break;
- case DRM_GPUVA_OP_REMAP:
+ case DRM_GPUVA_OP_REMAP: {
+ struct drm_gpuva *va = op->remap.unmap->va;
+
if (op->remap.prev)
- drm_gpuva_link(&new->prev->va);
+ drm_gpuva_link(&new->prev->va, va->vm_bo);
if (op->remap.next)
- drm_gpuva_link(&new->next->va);
- drm_gpuva_unlink(op->remap.unmap->va);
+ drm_gpuva_link(&new->next->va, va->vm_bo);
+ drm_gpuva_unlink(va);
break;
+ }
case DRM_GPUVA_OP_UNMAP:
drm_gpuva_unlink(op->unmap.va);
break;
@@ -1150,10 +1158,18 @@ nouveau_uvmm_bind_job_submit(struct nouveau_job *job)
list_for_each_op(op, &bind_job->ops) {
if (op->op == OP_MAP) {
- op->gem.obj = drm_gem_object_lookup(job->file_priv,
- op->gem.handle);
- if (!op->gem.obj)
+ struct drm_gem_object *obj;
+
+ obj = drm_gem_object_lookup(job->file_priv,
+ op->gem.handle);
+ if (!(op->gem.obj = obj))
return -ENOENT;
+
+ dma_resv_lock(obj->resv, NULL);
+ op->vm_bo = drm_gpuvm_bo_obtain(&uvmm->base, obj);
+ dma_resv_unlock(obj->resv);
+ if (IS_ERR(op->vm_bo))
+ return PTR_ERR(op->vm_bo);
}
ret = bind_validate_op(job, op);
@@ -1364,7 +1380,7 @@ nouveau_uvmm_bind_job_submit(struct nouveau_job *job)
case OP_UNMAP_SPARSE:
case OP_MAP:
case OP_UNMAP:
- bind_link_gpuvas(op->ops, &op->new);
+ bind_link_gpuvas(op);
break;
default:
break;
@@ -1511,6 +1527,12 @@ nouveau_uvmm_bind_job_free_work_fn(struct work_struct
*work)
if (!IS_ERR_OR_NULL(op->ops))
drm_gpuva_ops_free(&uvmm->base, op->ops);
+ if (!IS_ERR_OR_NULL(op->vm_bo)) {
+ dma_resv_lock(obj->resv, NULL);
+ drm_gpuvm_bo_put(op->vm_bo);
+ dma_resv_unlock(obj->resv);
+ }
+
if (obj)
drm_gem_object_put(obj);
}
@@ -1776,15 +1798,18 @@ void
nouveau_uvmm_bo_map_all(struct nouveau_bo *nvbo, struct nouveau_mem *mem)
{
struct drm_gem_object *obj = &nvbo->bo.base;
+ struct drm_gpuvm_bo *vm_bo;
struct drm_gpuva *va;
dma_resv_assert_held(obj->resv);
- drm_gem_for_each_gpuva(va, obj) {
- struct nouveau_uvma *uvma = uvma_from_va(va);
+ drm_gem_for_each_gpuvm_bo(vm_bo, obj) {
+ drm_gpuvm_bo_for_each_va(va, vm_bo) {
+ struct nouveau_uvma *uvma = uvma_from_va(va);
- nouveau_uvma_map(uvma, mem);
- drm_gpuva_invalidate(va, false);
+ nouveau_uvma_map(uvma, mem);
+ drm_gpuva_invalidate(va, false);
+ }
}
}
@@ -1792,15 +1817,18 @@ void
nouveau_uvmm_bo_unmap_all(struct nouveau_bo *nvbo)
{
struct drm_gem_object *obj = &nvbo->bo.base;
+ struct drm_gpuvm_bo *vm_bo;
struct drm_gpuva *va;
dma_resv_assert_held(obj->resv);
- drm_gem_for_each_gpuva(va, obj) {
- struct nouveau_uvma *uvma = uvma_from_va(va);
+ drm_gem_for_each_gpuvm_bo(vm_bo, obj) {
+ drm_gpuvm_bo_for_each_va(va, vm_bo) {
+ struct nouveau_uvma *uvma = uvma_from_va(va);
- nouveau_uvma_unmap(uvma);
- drm_gpuva_invalidate(va, true);
+ nouveau_uvma_unmap(uvma);
+ drm_gpuva_invalidate(va, true);
+ }
}
}
diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h
index 16364487fde9..369505447acd 100644
--- a/include/drm/drm_gem.h
+++ b/include/drm/drm_gem.h
@@ -580,7 +580,7 @@ int drm_gem_evict(struct drm_gem_object *obj);
* drm_gem_gpuva_init() - initialize the gpuva list of a GEM object
* @obj: the &drm_gem_object
*
- * This initializes the &drm_gem_object's &drm_gpuva list.
+ * This initializes the &drm_gem_object's &drm_gpuvm_bo list.
*
* Calling this function is only necessary for drivers intending to support the
* &drm_driver_feature DRIVER_GEM_GPUVA.
@@ -593,28 +593,28 @@ static inline void drm_gem_gpuva_init(struct
drm_gem_object *obj)
}
/**
- * drm_gem_for_each_gpuva() - iternator to walk over a list of gpuvas
- * @entry__: &drm_gpuva structure to assign to in each iteration step
- * @obj__: the &drm_gem_object the &drm_gpuvas to walk are associated
with
+ * drm_gem_for_each_gpuvm_bo() - iterator to walk over a list of
&drm_gpuvm_bo
+ * @entry__: &drm_gpuvm_bo structure to assign to in each iteration step
+ * @obj__: the &drm_gem_object the &drm_gpuvm_bo to walk are associated
with
*
- * This iterator walks over all &drm_gpuva structures associated with the
- * &drm_gpuva_manager.
+ * This iterator walks over all &drm_gpuvm_bo structures associated with
the
+ * &drm_gem_object.
*/
-#define drm_gem_for_each_gpuva(entry__, obj__) \
- list_for_each_entry(entry__, &(obj__)->gpuva.list, gem.entry)
+#define drm_gem_for_each_gpuvm_bo(entry__, obj__) \
+ list_for_each_entry(entry__, &(obj__)->gpuva.list, list.entry.gem)
/**
- * drm_gem_for_each_gpuva_safe() - iternator to safely walk over a list of
- * gpuvas
- * @entry__: &drm_gpuva structure to assign to in each iteration step
- * @next__: &next &drm_gpuva to store the next step
- * @obj__: the &drm_gem_object the &drm_gpuvas to walk are associated
with
+ * drm_gem_for_each_gpuvm_bo_safe() - iterator to safely walk over a list of
+ * &drm_gpuvm_bo
+ * @entry__: &drm_gpuvm_bostructure to assign to in each iteration step
+ * @next__: &next &drm_gpuvm_bo to store the next step
+ * @obj__: the &drm_gem_object the &drm_gpuvm_bo to walk are associated
with
*
- * This iterator walks over all &drm_gpuva structures associated with the
+ * This iterator walks over all &drm_gpuvm_bo structures associated with
the
* &drm_gem_object. It is implemented with list_for_each_entry_safe(),
hence
* it is save against removal of elements.
*/
-#define drm_gem_for_each_gpuva_safe(entry__, next__, obj__) \
- list_for_each_entry_safe(entry__, next__, &(obj__)->gpuva.list,
gem.entry)
+#define drm_gem_for_each_gpuvm_bo_safe(entry__, next__, obj__) \
+ list_for_each_entry_safe(entry__, next__, &(obj__)->gpuva.list,
list.entry.gem)
#endif /* __DRM_GEM_H__ */
diff --git a/include/drm/drm_gpuvm.h b/include/drm/drm_gpuvm.h
index 13539f32c2e2..ddb0b8d323cf 100644
--- a/include/drm/drm_gpuvm.h
+++ b/include/drm/drm_gpuvm.h
@@ -26,12 +26,14 @@
*/
#include <linux/list.h>
+#include <linux/dma-resv.h>
#include <linux/rbtree.h>
#include <linux/types.h>
#include <drm/drm_gem.h>
struct drm_gpuvm;
+struct drm_gpuvm_bo;
struct drm_gpuvm_ops;
/**
@@ -72,6 +74,12 @@ struct drm_gpuva {
*/
struct drm_gpuvm *vm;
+ /**
+ * @vm_bo: the &drm_gpuvm_bo abstraction for the mapped
+ * &drm_gem_object
+ */
+ struct drm_gpuvm_bo *vm_bo;
+
/**
* @flags: the &drm_gpuva_flags for this mapping
*/
@@ -107,7 +115,7 @@ struct drm_gpuva {
struct drm_gem_object *obj;
/**
- * @entry: the &list_head to attach this object to a &drm_gem_object
+ * @entry: the &list_head to attach this object to a &drm_gpuvm_bo
*/
struct list_head entry;
} gem;
@@ -140,7 +148,7 @@ struct drm_gpuva {
int drm_gpuva_insert(struct drm_gpuvm *gpuvm, struct drm_gpuva *va);
void drm_gpuva_remove(struct drm_gpuva *va);
-void drm_gpuva_link(struct drm_gpuva *va);
+void drm_gpuva_link(struct drm_gpuva *va, struct drm_gpuvm_bo *vm_bo);
void drm_gpuva_unlink(struct drm_gpuva *va);
struct drm_gpuva *drm_gpuva_find(struct drm_gpuvm *gpuvm,
@@ -187,10 +195,16 @@ static inline bool drm_gpuva_invalidated(struct drm_gpuva
*va)
* enum drm_gpuvm_flags - flags for struct drm_gpuvm
*/
enum drm_gpuvm_flags {
+ /**
+ * @DRM_GPUVM_RESV_PROTECTED: GPUVM is protected externally by the
+ * GPUVM's &dma_resv lock
+ */
+ DRM_GPUVM_RESV_PROTECTED = (1 << 0),
+
/**
* @DRM_GPUVM_USERBITS: user defined bits
*/
- DRM_GPUVM_USERBITS = (1 << 0),
+ DRM_GPUVM_USERBITS = (1 << 1),
};
/**
@@ -272,6 +286,19 @@ bool drm_gpuvm_interval_empty(struct drm_gpuvm *gpuvm, u64
addr, u64 range);
struct drm_gem_object *
drm_gpuvm_root_object_alloc(struct drm_device *drm);
+/**
+ * drm_gpuvm_resv_protected() - indicates whether &DRM_GPUVM_RESV_PROTECTED
is
+ * set
+ * @gpuvm: the &drm_gpuvm
+ *
+ * Returns: true if &DRM_GPUVM_RESV_PROTECTED is set, false otherwise.
+ */
+static inline bool
+drm_gpuvm_resv_protected(struct drm_gpuvm *gpuvm)
+{
+ return gpuvm->flags & DRM_GPUVM_RESV_PROTECTED;
+}
+
/**
* drm_gpuvm_resv() - returns the &drm_gpuvm's &dma_resv
* @gpuvm__: the &drm_gpuvm
@@ -290,6 +317,12 @@ drm_gpuvm_root_object_alloc(struct drm_device *drm);
*/
#define drm_gpuvm_resv_obj(gpuvm__) ((gpuvm__)->r_obj)
+#define drm_gpuvm_resv_held(gpuvm__) \
+ dma_resv_held(drm_gpuvm_resv(gpuvm__))
+
+#define drm_gpuvm_resv_assert_held(gpuvm__) \
+ dma_resv_assert_held(drm_gpuvm_resv(gpuvm__))
+
#define drm_gpuvm_resv_held(gpuvm__) \
dma_resv_held(drm_gpuvm_resv(gpuvm__))
@@ -374,6 +407,117 @@ __drm_gpuva_next(struct drm_gpuva *va)
#define drm_gpuvm_for_each_va_safe(va__, next__, gpuvm__) \
list_for_each_entry_safe(va__, next__, &(gpuvm__)->rb.list, rb.entry)
+/**
+ * struct drm_gpuvm_bo - structure representing a &drm_gpuvm and
+ * &drm_gem_object combination
+ *
+ * This structure is an abstraction representing a &drm_gpuvm and
+ * &drm_gem_object combination. It serves as an indirection to accelerate
+ * iterating all &drm_gpuvas within a &drm_gpuvm backed by the same
+ * &drm_gem_object.
+ *
+ * Furthermore it is used cache evicted GEM objects for a certain GPU-VM to
+ * accelerate validation.
+ *
+ * Typically, drivers want to create an instance of a struct drm_gpuvm_bo once
+ * a GEM object is mapped first in a GPU-VM and release the instance once the
+ * last mapping of the GEM object in this GPU-VM is unmapped.
+ */
+struct drm_gpuvm_bo {
+
+ /**
+ * @vm: The &drm_gpuvm the @obj is mapped in.
+ */
+ struct drm_gpuvm *vm;
+
+ /**
+ * @obj: The &drm_gem_object being mapped in @vm.
+ */
+ struct drm_gem_object *obj;
+
+ /**
+ * @kref: The reference count for this &drm_gpuvm_bo.
+ */
+ struct kref kref;
+
+ /**
+ * @list: Structure containing all &list_heads.
+ */
+ struct {
+ /**
+ * @gpuva: The list of linked &drm_gpuvas.
+ */
+ struct list_head gpuva;
+
+ /**
+ * @entry: Structure containing all &list_heads serving as
+ * entry.
+ */
+ struct {
+ /**
+ * @gem: List entry to attach to the &drm_gem_objects
+ * gpuva list.
+ */
+ struct list_head gem;
+ } entry;
+ } list;
+};
+
+struct drm_gpuvm_bo *
+drm_gpuvm_bo_create(struct drm_gpuvm *gpuvm,
+ struct drm_gem_object *obj);
+
+struct drm_gpuvm_bo *
+drm_gpuvm_bo_obtain(struct drm_gpuvm *gpuvm,
+ struct drm_gem_object *obj);
+struct drm_gpuvm_bo *
+drm_gpuvm_bo_obtain_prealloc(struct drm_gpuvm_bo *vm_bo);
+
+/**
+ * drm_gpuvm_bo_get() - acquire a struct drm_gpuvm_bo reference
+ * @vm_bo: the &drm_gpuvm_bo to acquire the reference of
+ *
+ * This function acquires an additional reference to @vm_bo. It is illegal to
+ * call this without already holding a reference. No locks required.
+ */
+static inline struct drm_gpuvm_bo *
+drm_gpuvm_bo_get(struct drm_gpuvm_bo *vm_bo)
+{
+ kref_get(&vm_bo->kref);
+ return vm_bo;
+}
+
+void drm_gpuvm_bo_put(struct drm_gpuvm_bo *vm_bo);
+
+struct drm_gpuvm_bo *
+drm_gpuvm_bo_find(struct drm_gpuvm *gpuvm,
+ struct drm_gem_object *obj);
+
+/**
+ * drm_gpuvm_bo_for_each_va() - iterator to walk over a list of &drm_gpuva
+ * @va__: &drm_gpuva structure to assign to in each iteration step
+ * @vm_bo__: the &drm_gpuvm_bo the &drm_gpuva to walk are associated
with
+ *
+ * This iterator walks over all &drm_gpuva structures associated with the
+ * &drm_gpuvm_bo.
+ */
+#define drm_gpuvm_bo_for_each_va(va__, vm_bo__) \
+ list_for_each_entry(va__, &(vm_bo)->list.gpuva, gem.entry)
+
+/**
+ * drm_gpuvm_bo_for_each_va_safe() - iterator to safely walk over a list of
+ * &drm_gpuva
+ * @va__: &drm_gpuva structure to assign to in each iteration step
+ * @next__: &next &drm_gpuva to store the next step
+ * @vm_bo__: the &drm_gpuvm_bo the &drm_gpuva to walk are associated
with
+ *
+ * This iterator walks over all &drm_gpuva structures associated with the
+ * &drm_gpuvm_bo. It is implemented with list_for_each_entry_safe(), hence
+ * it is save against removal of elements.
+ */
+#define drm_gpuvm_bo_for_each_va_safe(va__, next__, vm_bo__) \
+ list_for_each_entry_safe(va__, next__, &(vm_bo)->list.gpuva, gem.entry)
+
/**
* enum drm_gpuva_op_type - GPU VA operation type
*
@@ -643,8 +787,7 @@ drm_gpuvm_prefetch_ops_create(struct drm_gpuvm *gpuvm,
u64 addr, u64 range);
struct drm_gpuva_ops *
-drm_gpuvm_gem_unmap_ops_create(struct drm_gpuvm *gpuvm,
- struct drm_gem_object *obj);
+drm_gpuvm_bo_unmap_ops_create(struct drm_gpuvm_bo *vm_bo);
void drm_gpuva_ops_free(struct drm_gpuvm *gpuvm,
struct drm_gpuva_ops *ops);
@@ -688,6 +831,30 @@ struct drm_gpuvm_ops {
*/
void (*op_free)(struct drm_gpuva_op *op);
+ /**
+ * @vm_bo_alloc: called when the &drm_gpuvm allocates
+ * a struct drm_gpuvm_bo
+ *
+ * Some drivers may want to embed struct drm_gpuvm_bo into driver
+ * specific structures. By implementing this callback drivers can
+ * allocate memory accordingly.
+ *
+ * This callback is optional.
+ */
+ struct drm_gpuvm_bo *(*vm_bo_alloc)(void);
+
+ /**
+ * @vm_bo_free: called when the &drm_gpuvm frees a
+ * struct drm_gpuvm_bo
+ *
+ * Some drivers may want to embed struct drm_gpuvm_bo into driver
+ * specific structures. By implementing this callback drivers can
+ * free the previously allocated memory accordingly.
+ *
+ * This callback is optional.
+ */
+ void (*vm_bo_free)(struct drm_gpuvm_bo *vm_bo);
+
/**
* @sm_step_map: called from &drm_gpuvm_sm_map to finally insert the
* mapping once all previous steps were completed
--
2.41.0
Thomas Hellström
2023-Oct-13 12:30 UTC
[Nouveau] [PATCH drm-misc-next v6 3/6] drm/gpuvm: add an abstraction for a VM / BO combination
On Mon, 2023-10-09 at 01:32 +0200, Danilo Krummrich wrote:> Add an abstraction layer between the drm_gpuva mappings of a > particular > drm_gem_object and this GEM object itself. The abstraction represents > a > combination of a drm_gem_object and drm_gpuvm. The drm_gem_object > holds > a list of drm_gpuvm_bo structures (the structure representing this > abstraction), while each drm_gpuvm_bo contains list of mappings of > this > GEM object. > > This has multiple advantages: > > 1) We can use the drm_gpuvm_bo structure to attach it to various > lists > ?? of the drm_gpuvm. This is useful for tracking external and evicted > ?? objects per VM, which is introduced in subsequent patches. > > 2) Finding mappings of a certain drm_gem_object mapped in a certain > ?? drm_gpuvm becomes much cheaper. > > 3) Drivers can derive and extend the structure to easily represent > ?? driver specific states of a BO for a certain GPUVM. > > The idea of this abstraction was taken from amdgpu, hence the credit > for > this idea goes to the developers of amdgpu. > > Cc: Christian K?nig <christian.koenig at amd.com> > Signed-off-by: Danilo Krummrich <dakr at redhat.com> > --- > ?drivers/gpu/drm/drm_gpuvm.c??????????? | 332 +++++++++++++++++++++-- > -- > ?drivers/gpu/drm/nouveau/nouveau_uvmm.c |? 64 +++-- > ?include/drm/drm_gem.h????????????????? |? 32 +-- > ?include/drm/drm_gpuvm.h??????????????? | 177 ++++++++++++- > ?4 files changed, 521 insertions(+), 84 deletions(-) > > diff --git a/drivers/gpu/drm/drm_gpuvm.c > b/drivers/gpu/drm/drm_gpuvm.c > index 6368dfdbe9dd..28282283ddaf 100644 > --- a/drivers/gpu/drm/drm_gpuvm.c > +++ b/drivers/gpu/drm/drm_gpuvm.c > @@ -70,6 +70,18 @@ > ? * &drm_gem_object, such as the &drm_gem_object containing the root > page table, > ? * but it can also be a 'dummy' object, which can be allocated with > ? * drm_gpuvm_root_object_alloc(). > + * > + * In order to connect a struct drm_gpuva its backing > &drm_gem_object eachNIT: Same as previous patch regarding kerneldoc references> + * &drm_gem_object maintains a list of &drm_gpuvm_bo structures, and > each > + * &drm_gpuvm_bo contains a list of &&drm_gpuva structures. > + * > + * A &drm_gpuvm_bo is an abstraction that represents a combination > of a > + * &drm_gpuvm and a &drm_gem_object. Every such combination should > be unique. > + * This is ensured by the API through drm_gpuvm_bo_obtain() and > + * drm_gpuvm_bo_obtain_prealloc() which first look into the > corresponding > + * &drm_gem_object list of &drm_gpuvm_bos for an existing instance > of this > + * particular combination. If not existent a new instance is created > and linked > + * to the &drm_gem_object. > ? */ > ? > ?/** > @@ -395,21 +407,28 @@ > ?/** > ? * DOC: Locking > ? * > - * Generally, the GPU VA manager does not take care of locking > itself, it is > - * the drivers responsibility to take care about locking. Drivers > might want to > - * protect the following operations: inserting, removing and > iterating > - * &drm_gpuva objects as well as generating all kinds of operations, > such as > - * split / merge or prefetch. > - * > - * The GPU VA manager also does not take care of the locking of the > backing > - * &drm_gem_object buffers GPU VA lists by itself; drivers are > responsible to > - * enforce mutual exclusion using either the GEMs dma_resv lock or > alternatively > - * a driver specific external lock. For the latter see also > - * drm_gem_gpuva_set_lock(). > - * > - * However, the GPU VA manager contains lockdep checks to ensure > callers of its > - * API hold the corresponding lock whenever the &drm_gem_objects GPU > VA list is > - * accessed by functions such as drm_gpuva_link() or > drm_gpuva_unlink(). > + * In terms of managing &drm_gpuva entries DRM GPUVM does not take > care of > + * locking itself, it is the drivers responsibility to take care > about locking. > + * Drivers might want to protect the following operations: > inserting, removing > + * and iterating &drm_gpuva objects as well as generating all kinds > of > + * operations, such as split / merge or prefetch. > + * > + * DRM GPUVM also does not take care of the locking of the backing > + * &drm_gem_object buffers GPU VA lists and &drm_gpuvm_bo > abstractions by > + * itself; drivers are responsible to enforce mutual exclusion using > either the > + * GEMs dma_resv lock or alternatively a driver specific external > lock. For the > + * latter see also drm_gem_gpuva_set_lock(). > + * > + * However, DRM GPUVM contains lockdep checks to ensure callers of > its API hold > + * the corresponding lock whenever the &drm_gem_objects GPU VA list > is accessed > + * by functions such as drm_gpuva_link() or drm_gpuva_unlink(), but > also > + * drm_gpuvm_bo_obtain() and drm_gpuvm_bo_put(). > + * > + * The latter is required since on creation and destruction of a > &drm_gpuvm_bo > + * the &drm_gpuvm_bo is attached / removed from the &drm_gem_objects > gpuva list. > + * Subsequent calls to drm_gpuvm_bo_obtain() for the same &drm_gpuvm > and > + * &drm_gem_object must be able to observe previous creations and > destructions > + * of &drm_gpuvm_bos in order to keep instances unique. > ? */ > ? > ?/** > @@ -439,6 +458,7 @@ > ? *?????{ > ? *?????????????struct drm_gpuva_ops *ops; > ? *?????????????struct drm_gpuva_op *op > + *?????????????struct drm_gpuvm_bo *vm_bo; > ? * > ? *?????????????driver_lock_va_space(); > ? *?????????????ops = drm_gpuvm_sm_map_ops_create(gpuvm, addr, range, > @@ -446,6 +466,10 @@ > ? *?????????????if (IS_ERR(ops)) > ? *?????????????????????return PTR_ERR(ops); > ? * > + *?????????????vm_bo = drm_gpuvm_bo_obtain(gpuvm, obj); > + *?????????????if (IS_ERR(vm_bo)) > + *?????????????????????return PTR_ERR(vm_bo); > + * > ? *?????????????drm_gpuva_for_each_op(op, ops) { > ? *?????????????????????struct drm_gpuva *va; > ? * > @@ -458,7 +482,7 @@ > ? * > ? *?????????????????????????????driver_vm_map(); > ? *?????????????????????????????drm_gpuva_map(gpuvm, va, &op->map); > - *?????????????????????????????drm_gpuva_link(va); > + *?????????????????????????????drm_gpuva_link(va, vm_bo); > ? * > ? *?????????????????????????????break; > ? *?????????????????????case DRM_GPUVA_OP_REMAP: { > @@ -485,11 +509,11 @@ > ? *?????????????????????????????driver_vm_remap(); > ? *?????????????????????????????drm_gpuva_remap(prev, next, &op- > >remap); > ? * > - *?????????????????????????????drm_gpuva_unlink(va); > ? *?????????????????????????????if (prev) > - *?????????????????????????????????????drm_gpuva_link(prev); > + *?????????????????????????????????????drm_gpuva_link(prev, va- > >vm_bo); > ? *?????????????????????????????if (next) > - *?????????????????????????????????????drm_gpuva_link(next); > + *?????????????????????????????????????drm_gpuva_link(next, va- > >vm_bo); > + *?????????????????????????????drm_gpuva_unlink(va); > ? * > ? *?????????????????????????????break; > ? *?????????????????????} > @@ -505,6 +529,7 @@ > ? *?????????????????????????????break; > ? *?????????????????????} > ? *?????????????} > + *?????????????drm_gpuvm_bo_put(vm_bo); > ? *?????????????driver_unlock_va_space(); > ? * > ? *?????????????return 0; > @@ -514,6 +539,7 @@ > ? * > ? *?????struct driver_context { > ? *?????????????struct drm_gpuvm *gpuvm; > + *?????????????struct drm_gpuvm_bo *vm_bo; > ? *?????????????struct drm_gpuva *new_va; > ? *?????????????struct drm_gpuva *prev_va; > ? *?????????????struct drm_gpuva *next_va; > @@ -534,6 +560,7 @@ > ? *?????????????????????????????? struct drm_gem_object *obj, u64 > offset) > ? *?????{ > ? *?????????????struct driver_context ctx; > + *?????????????struct drm_gpuvm_bo *vm_bo; > ? *?????????????struct drm_gpuva_ops *ops; > ? *?????????????struct drm_gpuva_op *op; > ? *?????????????int ret = 0; > @@ -543,16 +570,23 @@ > ? *?????????????ctx.new_va = kzalloc(sizeof(*ctx.new_va), > GFP_KERNEL); > ? *?????????????ctx.prev_va = kzalloc(sizeof(*ctx.prev_va), > GFP_KERNEL); > ? *?????????????ctx.next_va = kzalloc(sizeof(*ctx.next_va), > GFP_KERNEL); > - *?????????????if (!ctx.new_va || !ctx.prev_va || !ctx.next_va) { > + *?????????????ctx.vm_bo = drm_gpuvm_bo_create(gpuvm, obj); > + *?????????????if (!ctx.new_va || !ctx.prev_va || !ctx.next_va || > !vm_bo) { > ? *?????????????????????ret = -ENOMEM; > ? *?????????????????????goto out; > ? *?????????????} > ? * > + *?????????????// Typically protected with a driver specific GEM > gpuva lock > + *?????????????// used in the fence signaling path for > drm_gpuva_link() and > + *?????????????// drm_gpuva_unlink(), hence pre-allocate. > + *?????????????ctx.vm_bo = drm_gpuvm_bo_obtain_prealloc(ctx.vm_bo); > + * > ? *?????????????driver_lock_va_space(); > ? *?????????????ret = drm_gpuvm_sm_map(gpuvm, &ctx, addr, range, obj, > offset); > ? *?????????????driver_unlock_va_space(); > ? * > ? *?????out: > + *?????????????drm_gpuvm_bo_put(ctx.vm_bo); > ? *?????????????kfree(ctx.new_va); > ? *?????????????kfree(ctx.prev_va); > ? *?????????????kfree(ctx.next_va); > @@ -565,7 +599,7 @@ > ? * > ? *?????????????drm_gpuva_map(ctx->vm, ctx->new_va, &op->map); > ? * > - *?????????????drm_gpuva_link(ctx->new_va); > + *?????????????drm_gpuva_link(ctx->new_va, ctx->vm_bo); > ? * > ? *?????????????// prevent the new GPUVA from being freed in > ? *?????????????// driver_mapping_create() > @@ -577,22 +611,23 @@ > ? *?????int driver_gpuva_remap(struct drm_gpuva_op *op, void *__ctx) > ? *?????{ > ? *?????????????struct driver_context *ctx = __ctx; > + *?????????????struct drm_gpuva *va = op->remap.unmap->va; > ? * > ? *?????????????drm_gpuva_remap(ctx->prev_va, ctx->next_va, &op- > >remap); > ? * > - *?????????????drm_gpuva_unlink(op->remap.unmap->va); > - *?????????????kfree(op->remap.unmap->va); > - * > ? *?????????????if (op->remap.prev) { > - *?????????????????????drm_gpuva_link(ctx->prev_va); > + *?????????????????????drm_gpuva_link(ctx->prev_va, va->vm_bo); > ? *?????????????????????ctx->prev_va = NULL; > ? *?????????????} > ? * > ? *?????????????if (op->remap.next) { > - *?????????????????????drm_gpuva_link(ctx->next_va); > + *?????????????????????drm_gpuva_link(ctx->next_va, va->vm_bo); > ? *?????????????????????ctx->next_va = NULL; > ? *?????????????} > ? * > + *?????????????drm_gpuva_unlink(va); > + *?????????????kfree(va); > + * > ? *?????????????return 0; > ? *?????} > ? * > @@ -771,6 +806,194 @@ drm_gpuvm_destroy(struct drm_gpuvm *gpuvm) > ?} > ?EXPORT_SYMBOL_GPL(drm_gpuvm_destroy); > ? > +/** > + * drm_gpuvm_bo_create() - create a new instance of struct > drm_gpuvm_bo > + * @gpuvm: The &drm_gpuvm the @obj is mapped in. > + * @obj: The &drm_gem_object being mapped in the @gpuvm. > + * > + * If provided by the driver, this function uses the &drm_gpuvm_ops > + * vm_bo_alloc() callback to allocate. > + * > + * Returns: a pointer to the &drm_gpuvm_bo on success, NULL onKerneldoc uses "Return:" rather than "Returns:", (This seems to a common thing throughout the series).> failure > + */ > +struct drm_gpuvm_bo *Any particular reason there's line-break after the function type even when it fits the ~100 char limit?> +drm_gpuvm_bo_create(struct drm_gpuvm *gpuvm, > +?????????????????? struct drm_gem_object *obj)> +{ > +???????const struct drm_gpuvm_ops *ops = gpuvm->ops; > +???????struct drm_gpuvm_bo *vm_bo; > + > +???????if (ops && ops->vm_bo_alloc) > +???????????????vm_bo = ops->vm_bo_alloc(); > +???????else > +???????????????vm_bo = kzalloc(sizeof(*vm_bo), GFP_KERNEL); > + > +???????if (unlikely(!vm_bo)) > +???????????????return NULL; > + > +???????vm_bo->vm = gpuvm; > +???????vm_bo->obj = obj; > + > +???????kref_init(&vm_bo->kref); > +???????INIT_LIST_HEAD(&vm_bo->list.gpuva); > +???????INIT_LIST_HEAD(&vm_bo->list.entry.gem); > + > +???????drm_gem_object_get(obj);Perhaps group this with the vm_bo->obj assignment to emphasize that that's the pointer that gets the reference?> + > +???????return vm_bo; > +} > +EXPORT_SYMBOL_GPL(drm_gpuvm_bo_create); > + > +static void > +drm_gpuvm_bo_destroy(struct kref *kref) > +{ > +???????struct drm_gpuvm_bo *vm_bo = container_of(kref, struct > drm_gpuvm_bo, > +???????????????????????????????????????????????? kref); > +???????struct drm_gpuvm *gpuvm = vm_bo->vm; > +???????const struct drm_gpuvm_ops *ops = gpuvm->ops; > +???????struct drm_gem_object *obj = vm_bo->obj; > +???????bool lock = !drm_gpuvm_resv_protected(gpuvm); > + > +???????drm_gem_gpuva_assert_lock_held(obj); > +???????if (!lock) > +???????????????drm_gpuvm_resv_assert_held(gpuvm); > + > +???????list_del(&vm_bo->list.entry.gem); > + > +???????drm_gem_object_put(obj);Not sure if we have any drivers utilizing vm_bo_free() yet, but it might make sense to move the drm_gem_object_put() until after the freeing below, in case vm_bo_free() wants to use it?> + > +???????if (ops && ops->vm_bo_free) > +???????????????ops->vm_bo_free(vm_bo); > +???????else > +???????????????kfree(vm_bo); > +} > + > +/** > + * drm_gpuvm_bo_put() - drop a struct drm_gpuvm_bo reference > + * @vm_bo: the &drm_gpuvm_bo to release the reference of > + * > + * This releases a reference to @vm_bo. > + * > + * If the reference count drops to zero, the &gpuvm_bo is destroyed, > which > + * includes removing it from the GEMs gpuva list. Hence, if a call > to this > + * function can potentially let the reference count to zero the > caller must > + * hold the dma-resv or driver specific GEM gpuva lock. > + */ > +void > +drm_gpuvm_bo_put(struct drm_gpuvm_bo *vm_bo) > +{ > +???????if (vm_bo) > +???????????????kref_put(&vm_bo->kref, drm_gpuvm_bo_destroy); > +} > +EXPORT_SYMBOL_GPL(drm_gpuvm_bo_put); > + > +static struct drm_gpuvm_bo * > +__drm_gpuvm_bo_find(struct drm_gpuvm *gpuvm, > +?????????????????? struct drm_gem_object *obj) > +{ > +???????struct drm_gpuvm_bo *vm_bo; > + > +???????drm_gem_gpuva_assert_lock_held(obj); > + > +???????drm_gem_for_each_gpuvm_bo(vm_bo, obj) > +???????????????if (vm_bo->vm == gpuvm) > +???????????????????????return vm_bo; > + > +???????return NULL; > +} > + > +/** > + * drm_gpuvm_bo_find() - find the &drm_gpuvm_bo for the given > + * &drm_gpuvm and &drm_gem_object > + * @gpuvm: The &drm_gpuvm the @obj is mapped in. > + * @obj: The &drm_gem_object being mapped in the @gpuvm. > + * > + * Find the &drm_gpuvm_bo representing the combination of the given > + * &drm_gpuvm and &drm_gem_object. If found, increases the reference > + * count of the &drm_gpuvm_bo accordingly. > + * > + * Returns: a pointer to the &drm_gpuvm_bo on success, NULL on > failure > + */ > +struct drm_gpuvm_bo * > +drm_gpuvm_bo_find(struct drm_gpuvm *gpuvm, > +???????????????? struct drm_gem_object *obj) > +{ > +???????struct drm_gpuvm_bo *vm_bo = __drm_gpuvm_bo_find(gpuvm, obj); > + > +???????return vm_bo ? drm_gpuvm_bo_get(vm_bo) : NULL; > +} > +EXPORT_SYMBOL_GPL(drm_gpuvm_bo_find); > + > +/** > + * drm_gpuvm_bo_obtain() - obtains and instance of the &drm_gpuvm_bo > for the > + * given &drm_gpuvm and &drm_gem_object > + * @gpuvm: The &drm_gpuvm the @obj is mapped in. > + * @obj: The &drm_gem_object being mapped in the @gpuvm. > + * > + * Find the &drm_gpuvm_bo representing the combination of the given > + * &drm_gpuvm and &drm_gem_object. If found, increases the reference > + * count of the &drm_gpuvm_bo accordingly. If not found, allocates a > new > + * &drm_gpuvm_bo. > + * > + * A new &drm_gpuvm_bo is added to the GEMs gpuva list. > + * > + * Returns: a pointer to the &drm_gpuvm_bo on success, an ERR_PTR on > failure > + */ > +struct drm_gpuvm_bo * > +drm_gpuvm_bo_obtain(struct drm_gpuvm *gpuvm, > +?????????????????? struct drm_gem_object *obj) > +{ > +???????struct drm_gpuvm_bo *vm_bo; > + > +???????vm_bo = drm_gpuvm_bo_find(gpuvm, obj); > +???????if (vm_bo) > +???????????????return vm_bo; > + > +???????vm_bo = drm_gpuvm_bo_create(gpuvm, obj); > +???????if (!vm_bo) > +???????????????return ERR_PTR(-ENOMEM); > + > +???????list_add_tail(&vm_bo->list.entry.gem, &obj->gpuva.list);Lockdep check?> + > +???????return vm_bo; > +} > +EXPORT_SYMBOL_GPL(drm_gpuvm_bo_obtain); > + > +/** > + * drm_gpuvm_bo_obtain_prealloc() - obtains and instance of the > &drm_gpuvm_bo > + * for the given &drm_gpuvm and &drm_gem_object > + * @__vm_bo: A pre-allocated struct drm_gpuvm_bo. > + * > + * Find the &drm_gpuvm_bo representing the combination of the given > + * &drm_gpuvm and &drm_gem_object. If found, increases the reference > + * count of the found &drm_gpuvm_bo accordingly, while the @__vm_bo > reference > + * count is decreased. If not found @__vm_bo is returned without > further > + * increase of the reference count. > + * > + * A new &drm_gpuvm_bo is added to the GEMs gpuva list. > + * > + * Returns: a pointer to the found &drm_gpuvm_bo or @__vm_bo if no > existing > + * &drm_gpuvm_bo was found > + */ > +struct drm_gpuvm_bo * > +drm_gpuvm_bo_obtain_prealloc(struct drm_gpuvm_bo *__vm_bo) > +{ > +???????struct drm_gpuvm *gpuvm = __vm_bo->vm; > +???????struct drm_gem_object *obj = __vm_bo->obj; > +???????struct drm_gpuvm_bo *vm_bo; > + > +???????vm_bo = drm_gpuvm_bo_find(gpuvm, obj); > +???????if (vm_bo) { > +???????????????drm_gpuvm_bo_put(__vm_bo); > +???????????????return vm_bo; > +???????} > + > +???????list_add_tail(&__vm_bo->list.entry.gem, &obj->gpuva.list);Perhaps a lockdep check here?> + > +???????return __vm_bo; > +} > +EXPORT_SYMBOL_GPL(drm_gpuvm_bo_obtain_prealloc); > + > ?static int > ?__drm_gpuva_insert(struct drm_gpuvm *gpuvm, > ?????????????????? struct drm_gpuva *va) > @@ -860,24 +1083,33 @@ EXPORT_SYMBOL_GPL(drm_gpuva_remove); > ?/** > ? * drm_gpuva_link() - link a &drm_gpuva > ? * @va: the &drm_gpuva to link > + * @vm_bo: the &drm_gpuvm_bo to add the &drm_gpuva to > ? * > - * This adds the given &va to the GPU VA list of the &drm_gem_object > it is > - * associated with. > + * This adds the given &va to the GPU VA list of the &drm_gpuvm_bo > and the > + * &drm_gpuvm_bo to the &drm_gem_object it is associated with. > + * > + * For every &drm_gpuva entry added to the &drm_gpuvm_bo an > additional > + * reference of the latter is taken. > ? * > ? * This function expects the caller to protect the GEM's GPUVA list > againstNIT: Referring to a "gem object" as a "GEM" catches my eye every time. Perhaps that has become common practice? With my "it used to be like.." hat on, I'd use gem object.> - * concurrent access using the GEMs dma_resv lock. > + * concurrent access using either the GEMs dma_resv lock or a driver > specific > + * lock set through drm_gem_gpuva_set_lock(). > ? */ > ?void > -drm_gpuva_link(struct drm_gpuva *va) > +drm_gpuva_link(struct drm_gpuva *va, struct drm_gpuvm_bo *vm_bo) > ?{ > ????????struct drm_gem_object *obj = va->gem.obj; > ? > ????????if (unlikely(!obj)) > ????????????????return; > ? > +???????WARN_ON(obj != vm_bo->obj);Can we use drm_WARN here?> ????????drm_gem_gpuva_assert_lock_held(obj); > ? > -???????list_add_tail(&va->gem.entry, &obj->gpuva.list); > +???????drm_gpuvm_bo_get(vm_bo); > + > +???????va->vm_bo = vm_bo; > +???????list_add_tail(&va->gem.entry, &vm_bo->list.gpuva); > ?} > ?EXPORT_SYMBOL_GPL(drm_gpuva_link); > ? > @@ -888,13 +1120,22 @@ EXPORT_SYMBOL_GPL(drm_gpuva_link); > ? * This removes the given &va from the GPU VA list of the > &drm_gem_object it is > ? * associated with. > ? * > + * This removes the given &va from the GPU VA list of the > &drm_gpuvm_bo and > + * the &drm_gpuvm_bo from the &drm_gem_object it is associated with > in case > + * this call unlinks the last &drm_gpuva from the &drm_gpuvm_bo. > + * > + * For every &drm_gpuva entry removed from the &drm_gpuvm_bo a > reference of > + * the latter is dropped. > + * > ? * This function expects the caller to protect the GEM's GPUVA list > against > - * concurrent access using the GEMs dma_resv lock. > + * concurrent access using either the GEMs dma_resv lock or a driver > specific > + * lock set through drm_gem_gpuva_set_lock(). > ? */ > ?void > ?drm_gpuva_unlink(struct drm_gpuva *va) > ?{ > ????????struct drm_gem_object *obj = va->gem.obj; > +???????struct drm_gpuvm_bo *vm_bo = va->vm_bo; > ? > ????????if (unlikely(!obj)) > ????????????????return; > @@ -902,6 +1143,9 @@ drm_gpuva_unlink(struct drm_gpuva *va) > ????????drm_gem_gpuva_assert_lock_held(obj); > ? > ????????list_del_init(&va->gem.entry); > +???????va->vm_bo = NULL; > + > +???????drm_gpuvm_bo_put(vm_bo); > ?} > ?EXPORT_SYMBOL_GPL(drm_gpuva_unlink); > ? > @@ -1046,10 +1290,10 @@ drm_gpuva_remap(struct drm_gpuva *prev, > ????????????????struct drm_gpuva *next, > ????????????????struct drm_gpuva_op_remap *op) > ?{ > -???????struct drm_gpuva *curr = op->unmap->va; > -???????struct drm_gpuvm *gpuvm = curr->vm; > +???????struct drm_gpuva *va = op->unmap->va; > +???????struct drm_gpuvm *gpuvm = va->vm; > ? > -???????drm_gpuva_remove(curr); > +???????drm_gpuva_remove(va); > ? > ????????if (op->prev) { > ????????????????drm_gpuva_init_from_op(prev, op->prev); > @@ -1693,9 +1937,8 @@ drm_gpuvm_prefetch_ops_create(struct drm_gpuvm > *gpuvm, > ?EXPORT_SYMBOL_GPL(drm_gpuvm_prefetch_ops_create); > ? > ?/** > - * drm_gpuvm_gem_unmap_ops_create() - creates the &drm_gpuva_ops to > unmap a GEM > - * @gpuvm: the &drm_gpuvm representing the GPU VA space > - * @obj: the &drm_gem_object to unmap > + * drm_gpuvm_bo_unmap_ops_create() - creates the &drm_gpuva_ops to > unmap a GEM > + * @vm_bo: the &drm_gpuvm_bo abstraction > ? * > ? * This function creates a list of operations to perform unmapping > for every > ? * GPUVA attached to a GEM. > @@ -1712,15 +1955,14 @@ > EXPORT_SYMBOL_GPL(drm_gpuvm_prefetch_ops_create); > ? * Returns: a pointer to the &drm_gpuva_ops on success, an ERR_PTR > on failure > ? */ > ?struct drm_gpuva_ops * > -drm_gpuvm_gem_unmap_ops_create(struct drm_gpuvm *gpuvm, > -????????????????????????????? struct drm_gem_object *obj) > +drm_gpuvm_bo_unmap_ops_create(struct drm_gpuvm_bo *vm_bo) > ?{ > ????????struct drm_gpuva_ops *ops; > ????????struct drm_gpuva_op *op; > ????????struct drm_gpuva *va; > ????????int ret; > ? > -???????drm_gem_gpuva_assert_lock_held(obj); > +???????drm_gem_gpuva_assert_lock_held(vm_bo->obj); > ? > ????????ops = kzalloc(sizeof(*ops), GFP_KERNEL); > ????????if (!ops) > @@ -1728,8 +1970,8 @@ drm_gpuvm_gem_unmap_ops_create(struct drm_gpuvm > *gpuvm, > ? > ????????INIT_LIST_HEAD(&ops->list); > ? > -???????drm_gem_for_each_gpuva(va, obj) { > -???????????????op = gpuva_op_alloc(gpuvm); > +???????drm_gpuvm_bo_for_each_va(va, vm_bo) { > +???????????????op = gpuva_op_alloc(vm_bo->vm); > ????????????????if (!op) { > ????????????????????????ret = -ENOMEM; > ????????????????????????goto err_free_ops; > @@ -1743,10 +1985,10 @@ drm_gpuvm_gem_unmap_ops_create(struct > drm_gpuvm *gpuvm, > ????????return ops; > ? > ?err_free_ops: > -???????drm_gpuva_ops_free(gpuvm, ops); > +???????drm_gpuva_ops_free(vm_bo->vm, ops); > ????????return ERR_PTR(ret); > ?} > -EXPORT_SYMBOL_GPL(drm_gpuvm_gem_unmap_ops_create); > +EXPORT_SYMBOL_GPL(drm_gpuvm_bo_unmap_ops_create); > ? > ?/** > ? * drm_gpuva_ops_free() - free the given &drm_gpuva_ops > diff --git a/drivers/gpu/drm/nouveau/nouveau_uvmm.c > b/drivers/gpu/drm/nouveau/nouveau_uvmm.c > index 93ad2ba7ec8b..4e46f850e65f 100644 > --- a/drivers/gpu/drm/nouveau/nouveau_uvmm.c > +++ b/drivers/gpu/drm/nouveau/nouveau_uvmm.c > @@ -62,6 +62,8 @@ struct bind_job_op { > ????????enum vm_bind_op op; > ????????u32 flags; > ? > +???????struct drm_gpuvm_bo *vm_bo; > + > ????????struct { > ????????????????u64 addr; > ????????????????u64 range; > @@ -1113,22 +1115,28 @@ bind_validate_region(struct nouveau_job *job) > ?} > ? > ?static void > -bind_link_gpuvas(struct drm_gpuva_ops *ops, struct > nouveau_uvma_prealloc *new) > +bind_link_gpuvas(struct bind_job_op *bop) > ?{ > +???????struct nouveau_uvma_prealloc *new = &bop->new; > +???????struct drm_gpuvm_bo *vm_bo = bop->vm_bo; > +???????struct drm_gpuva_ops *ops = bop->ops; > ????????struct drm_gpuva_op *op; > ? > ????????drm_gpuva_for_each_op(op, ops) { > ????????????????switch (op->op) { > ????????????????case DRM_GPUVA_OP_MAP: > -???????????????????????drm_gpuva_link(&new->map->va); > +???????????????????????drm_gpuva_link(&new->map->va, vm_bo); > ????????????????????????break; > -???????????????case DRM_GPUVA_OP_REMAP: > +???????????????case DRM_GPUVA_OP_REMAP: { > +???????????????????????struct drm_gpuva *va = op->remap.unmap->va; > + > ????????????????????????if (op->remap.prev) > -???????????????????????????????drm_gpuva_link(&new->prev->va); > +???????????????????????????????drm_gpuva_link(&new->prev->va, va- > >vm_bo); > ????????????????????????if (op->remap.next) > -???????????????????????????????drm_gpuva_link(&new->next->va); > -???????????????????????drm_gpuva_unlink(op->remap.unmap->va); > +???????????????????????????????drm_gpuva_link(&new->next->va, va- > >vm_bo); > +???????????????????????drm_gpuva_unlink(va); > ????????????????????????break; > +???????????????} > ????????????????case DRM_GPUVA_OP_UNMAP: > ????????????????????????drm_gpuva_unlink(op->unmap.va); > ????????????????????????break; > @@ -1150,10 +1158,18 @@ nouveau_uvmm_bind_job_submit(struct > nouveau_job *job) > ? > ????????list_for_each_op(op, &bind_job->ops) { > ????????????????if (op->op == OP_MAP) { > -???????????????????????op->gem.obj = drm_gem_object_lookup(job- > >file_priv, > -?????????????????????????????????????????????????????????? op- > >gem.handle); > -???????????????????????if (!op->gem.obj) > +???????????????????????struct drm_gem_object *obj; > + > +???????????????????????obj = drm_gem_object_lookup(job->file_priv, > +?????????????????????????????????????????????????? op->gem.handle); > +???????????????????????if (!(op->gem.obj = obj)) > ????????????????????????????????return -ENOENT; > + > +???????????????????????dma_resv_lock(obj->resv, NULL); > +???????????????????????op->vm_bo = drm_gpuvm_bo_obtain(&uvmm->base, > obj); > +???????????????????????dma_resv_unlock(obj->resv); > +???????????????????????if (IS_ERR(op->vm_bo)) > +???????????????????????????????return PTR_ERR(op->vm_bo); > ????????????????} > ? > ????????????????ret = bind_validate_op(job, op); > @@ -1364,7 +1380,7 @@ nouveau_uvmm_bind_job_submit(struct nouveau_job > *job) > ????????????????case OP_UNMAP_SPARSE: > ????????????????case OP_MAP: > ????????????????case OP_UNMAP: > -???????????????????????bind_link_gpuvas(op->ops, &op->new); > +???????????????????????bind_link_gpuvas(op); > ????????????????????????break; > ????????????????default: > ????????????????????????break; > @@ -1511,6 +1527,12 @@ nouveau_uvmm_bind_job_free_work_fn(struct > work_struct *work) > ????????????????if (!IS_ERR_OR_NULL(op->ops)) > ????????????????????????drm_gpuva_ops_free(&uvmm->base, op->ops); > ? > +???????????????if (!IS_ERR_OR_NULL(op->vm_bo)) { > +???????????????????????dma_resv_lock(obj->resv, NULL); > +???????????????????????drm_gpuvm_bo_put(op->vm_bo); > +???????????????????????dma_resv_unlock(obj->resv); > +???????????????} > + > ????????????????if (obj) > ????????????????????????drm_gem_object_put(obj); > ????????} > @@ -1776,15 +1798,18 @@ void > ?nouveau_uvmm_bo_map_all(struct nouveau_bo *nvbo, struct nouveau_mem > *mem) > ?{ > ????????struct drm_gem_object *obj = &nvbo->bo.base; > +???????struct drm_gpuvm_bo *vm_bo; > ????????struct drm_gpuva *va; > ? > ????????dma_resv_assert_held(obj->resv); > ? > -???????drm_gem_for_each_gpuva(va, obj) { > -???????????????struct nouveau_uvma *uvma = uvma_from_va(va); > +???????drm_gem_for_each_gpuvm_bo(vm_bo, obj) { > +???????????????drm_gpuvm_bo_for_each_va(va, vm_bo) { > +???????????????????????struct nouveau_uvma *uvma = uvma_from_va(va); > ? > -???????????????nouveau_uvma_map(uvma, mem); > -???????????????drm_gpuva_invalidate(va, false); > +???????????????????????nouveau_uvma_map(uvma, mem); > +???????????????????????drm_gpuva_invalidate(va, false); > +???????????????} > ????????} > ?} > ? > @@ -1792,15 +1817,18 @@ void > ?nouveau_uvmm_bo_unmap_all(struct nouveau_bo *nvbo) > ?{ > ????????struct drm_gem_object *obj = &nvbo->bo.base; > +???????struct drm_gpuvm_bo *vm_bo; > ????????struct drm_gpuva *va; > ? > ????????dma_resv_assert_held(obj->resv); > ? > -???????drm_gem_for_each_gpuva(va, obj) { > -???????????????struct nouveau_uvma *uvma = uvma_from_va(va); > +???????drm_gem_for_each_gpuvm_bo(vm_bo, obj) { > +???????????????drm_gpuvm_bo_for_each_va(va, vm_bo) { > +???????????????????????struct nouveau_uvma *uvma = uvma_from_va(va); > ? > -???????????????nouveau_uvma_unmap(uvma); > -???????????????drm_gpuva_invalidate(va, true); > +???????????????????????nouveau_uvma_unmap(uvma); > +???????????????????????drm_gpuva_invalidate(va, true); > +???????????????} > ????????} > ?} > ? > diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h > index 16364487fde9..369505447acd 100644 > --- a/include/drm/drm_gem.h > +++ b/include/drm/drm_gem.h > @@ -580,7 +580,7 @@ int drm_gem_evict(struct drm_gem_object *obj); > ? * drm_gem_gpuva_init() - initialize the gpuva list of a GEM object > ? * @obj: the &drm_gem_object > ? * > - * This initializes the &drm_gem_object's &drm_gpuva list. > + * This initializes the &drm_gem_object's &drm_gpuvm_bo list. > ? * > ? * Calling this function is only necessary for drivers intending to > support the > ? * &drm_driver_feature DRIVER_GEM_GPUVA. > @@ -593,28 +593,28 @@ static inline void drm_gem_gpuva_init(struct > drm_gem_object *obj) > ?} > ? > ?/** > - * drm_gem_for_each_gpuva() - iternator to walk over a list of > gpuvas > - * @entry__: &drm_gpuva structure to assign to in each iteration > step > - * @obj__: the &drm_gem_object the &drm_gpuvas to walk are > associated with > + * drm_gem_for_each_gpuvm_bo() - iterator to walk over a list of > &drm_gpuvm_bo > + * @entry__: &drm_gpuvm_bo structure to assign to in each iteration > step > + * @obj__: the &drm_gem_object the &drm_gpuvm_bo to walk are > associated with > ? * > - * This iterator walks over all &drm_gpuva structures associated > with the > - * &drm_gpuva_manager. > + * This iterator walks over all &drm_gpuvm_bo structures associated > with the > + * &drm_gem_object. > ? */ > -#define drm_gem_for_each_gpuva(entry__, obj__) \ > -???????list_for_each_entry(entry__, &(obj__)->gpuva.list, gem.entry) > +#define drm_gem_for_each_gpuvm_bo(entry__, obj__) \ > +???????list_for_each_entry(entry__, &(obj__)->gpuva.list, > list.entry.gem) > ? > ?/** > - * drm_gem_for_each_gpuva_safe() - iternator to safely walk over a > list of > - * gpuvas > - * @entry__: &drm_gpuva structure to assign to in each iteration > step > - * @next__: &next &drm_gpuva to store the next step > - * @obj__: the &drm_gem_object the &drm_gpuvas to walk are > associated with > + * drm_gem_for_each_gpuvm_bo_safe() - iterator to safely walk over a > list of > + * &drm_gpuvm_bo > + * @entry__: &drm_gpuvm_bostructure to assign to in each iteration > step > + * @next__: &next &drm_gpuvm_bo to store the next step > + * @obj__: the &drm_gem_object the &drm_gpuvm_bo to walk are > associated with > ? * > - * This iterator walks over all &drm_gpuva structures associated > with the > + * This iterator walks over all &drm_gpuvm_bo structures associated > with the > ? * &drm_gem_object. It is implemented with > list_for_each_entry_safe(), hence > ? * it is save against removal of elements. > ? */ > -#define drm_gem_for_each_gpuva_safe(entry__, next__, obj__) \ > -???????list_for_each_entry_safe(entry__, next__, &(obj__)- > >gpuva.list, gem.entry) > +#define drm_gem_for_each_gpuvm_bo_safe(entry__, next__, obj__) \ > +???????list_for_each_entry_safe(entry__, next__, &(obj__)- > >gpuva.list, list.entry.gem) > ? > ?#endif /* __DRM_GEM_H__ */ > diff --git a/include/drm/drm_gpuvm.h b/include/drm/drm_gpuvm.h > index 13539f32c2e2..ddb0b8d323cf 100644 > --- a/include/drm/drm_gpuvm.h > +++ b/include/drm/drm_gpuvm.h > @@ -26,12 +26,14 @@ > ? */ > ? > ?#include <linux/list.h> > +#include <linux/dma-resv.h> > ?#include <linux/rbtree.h> > ?#include <linux/types.h> > ? > ?#include <drm/drm_gem.h> > ? > ?struct drm_gpuvm; > +struct drm_gpuvm_bo; > ?struct drm_gpuvm_ops; > ? > ?/** > @@ -72,6 +74,12 @@ struct drm_gpuva { > ???????? */ > ????????struct drm_gpuvm *vm; > ? > +???????/** > +??????? * @vm_bo: the &drm_gpuvm_bo abstraction for the mapped > +??????? * &drm_gem_object > +??????? */ > +???????struct drm_gpuvm_bo *vm_bo; > + > ????????/** > ???????? * @flags: the &drm_gpuva_flags for this mapping > ???????? */ > @@ -107,7 +115,7 @@ struct drm_gpuva { > ????????????????struct drm_gem_object *obj; > ? > ????????????????/** > -??????????????? * @entry: the &list_head to attach this object to a > &drm_gem_object > +??????????????? * @entry: the &list_head to attach this object to a > &drm_gpuvm_bo > ???????????????? */ > ????????????????struct list_head entry; > ????????} gem; > @@ -140,7 +148,7 @@ struct drm_gpuva { > ?int drm_gpuva_insert(struct drm_gpuvm *gpuvm, struct drm_gpuva *va); > ?void drm_gpuva_remove(struct drm_gpuva *va); > ? > -void drm_gpuva_link(struct drm_gpuva *va); > +void drm_gpuva_link(struct drm_gpuva *va, struct drm_gpuvm_bo > *vm_bo); > ?void drm_gpuva_unlink(struct drm_gpuva *va); > ? > ?struct drm_gpuva *drm_gpuva_find(struct drm_gpuvm *gpuvm, > @@ -187,10 +195,16 @@ static inline bool drm_gpuva_invalidated(struct > drm_gpuva *va) > ? * enum drm_gpuvm_flags - flags for struct drm_gpuvm > ? */ > ?enum drm_gpuvm_flags { > +???????/** > +??????? * @DRM_GPUVM_RESV_PROTECTED: GPUVM is protected externally > by the > +??????? * GPUVM's &dma_resv lock > +??????? */ > +???????DRM_GPUVM_RESV_PROTECTED = (1 << 0), > + > ????????/** > ???????? * @DRM_GPUVM_USERBITS: user defined bits > ???????? */ > -???????DRM_GPUVM_USERBITS = (1 << 0), > +???????DRM_GPUVM_USERBITS = (1 << 1), > ?}; > ? > ?/** > @@ -272,6 +286,19 @@ bool drm_gpuvm_interval_empty(struct drm_gpuvm > *gpuvm, u64 addr, u64 range); > ?struct drm_gem_object * > ?drm_gpuvm_root_object_alloc(struct drm_device *drm); > ? > +/** > + * drm_gpuvm_resv_protected() - indicates whether > &DRM_GPUVM_RESV_PROTECTED is > + * set > + * @gpuvm: the &drm_gpuvm > + * > + * Returns: true if &DRM_GPUVM_RESV_PROTECTED is set, false > otherwise. > + */ > +static inline bool > +drm_gpuvm_resv_protected(struct drm_gpuvm *gpuvm) > +{ > +???????return gpuvm->flags & DRM_GPUVM_RESV_PROTECTED; > +} > + > ?/** > ? * drm_gpuvm_resv() - returns the &drm_gpuvm's &dma_resv > ? * @gpuvm__: the &drm_gpuvm > @@ -290,6 +317,12 @@ drm_gpuvm_root_object_alloc(struct drm_device > *drm); > ? */ > ?#define drm_gpuvm_resv_obj(gpuvm__) ((gpuvm__)->r_obj) > ? > +#define drm_gpuvm_resv_held(gpuvm__) \ > +???????dma_resv_held(drm_gpuvm_resv(gpuvm__)) > + > +#define drm_gpuvm_resv_assert_held(gpuvm__) \ > +???????dma_resv_assert_held(drm_gpuvm_resv(gpuvm__)) > + > ?#define drm_gpuvm_resv_held(gpuvm__) \ > ????????dma_resv_held(drm_gpuvm_resv(gpuvm__)) > ? > @@ -374,6 +407,117 @@ __drm_gpuva_next(struct drm_gpuva *va) > ?#define drm_gpuvm_for_each_va_safe(va__, next__, gpuvm__) \ > ????????list_for_each_entry_safe(va__, next__, &(gpuvm__)->rb.list, > rb.entry) > ? > +/** > + * struct drm_gpuvm_bo - structure representing a &drm_gpuvm and > + * &drm_gem_object combination > + * > + * This structure is an abstraction representing a &drm_gpuvm and > + * &drm_gem_object combination. It serves as an indirection to > accelerate > + * iterating all &drm_gpuvas within a &drm_gpuvm backed by the same > + * &drm_gem_object. > + * > + * Furthermore it is used cache evicted GEM objects for a certain > GPU-VM to > + * accelerate validation. > + * > + * Typically, drivers want to create an instance of a struct > drm_gpuvm_bo once > + * a GEM object is mapped first in a GPU-VM and release the instance > once the > + * last mapping of the GEM object in this GPU-VM is unmapped. > + */ > +struct drm_gpuvm_bo { > + > +???????/** > +??????? * @vm: The &drm_gpuvm the @obj is mapped in.Not refcounted. @vm may potentially be freed under us in the !RESV_PROTECTED case.> +??????? */ > +???????struct drm_gpuvm *vm; > + > +???????/** > +??????? * @obj: The &drm_gem_object being mapped in @vm.Refcounted pointer.> +??????? */ > +???????struct drm_gem_object *obj; > + > +???????/** > +??????? * @kref: The reference count for this &drm_gpuvm_bo. > +??????? */ > +???????struct kref kref; > + > +???????/** > +??????? * @list: Structure containing all &list_heads. > +??????? */ > +???????struct { > +???????????????/** > +??????????????? * @gpuva: The list of linked &drm_gpuvas. > +??????????????? */Here we should also document how we ensure gpvuas are kept alive. (which I presume is the lock protecting the gem object's vm_bo list must be held all the time any gpuva obtained from this list is being accessed).> +???????????????struct list_head gpuva; > + > +???????????????/** > +??????????????? * @entry: Structure containing all &list_heads > serving as > +??????????????? * entry. > +??????????????? */ > +???????????????struct { > +???????????????????????/** > +??????????????????????? * @gem: List entry to attach to the > &drm_gem_objects > +??????????????????????? * gpuva list. > +??????????????????????? */ > +???????????????????????struct list_head gem; > +???????????????} entry; > +???????} list; > +}; > + > +struct drm_gpuvm_bo * > +drm_gpuvm_bo_create(struct drm_gpuvm *gpuvm, > +?????????????????? struct drm_gem_object *obj); > + > +struct drm_gpuvm_bo * > +drm_gpuvm_bo_obtain(struct drm_gpuvm *gpuvm, > +?????????????????? struct drm_gem_object *obj); > +struct drm_gpuvm_bo * > +drm_gpuvm_bo_obtain_prealloc(struct drm_gpuvm_bo *vm_bo); > + > +/** > + * drm_gpuvm_bo_get() - acquire a struct drm_gpuvm_bo reference > + * @vm_bo: the &drm_gpuvm_bo to acquire the reference of > + * > + * This function acquires an additional reference to @vm_bo. It is > illegal to > + * call this without already holding a reference. No locks required. > + */ > +static inline struct drm_gpuvm_bo * > +drm_gpuvm_bo_get(struct drm_gpuvm_bo *vm_bo) > +{ > +???????kref_get(&vm_bo->kref); > +???????return vm_bo; > +} > + > +void drm_gpuvm_bo_put(struct drm_gpuvm_bo *vm_bo); > + > +struct drm_gpuvm_bo * > +drm_gpuvm_bo_find(struct drm_gpuvm *gpuvm, > +???????????????? struct drm_gem_object *obj); > + > +/** > + * drm_gpuvm_bo_for_each_va() - iterator to walk over a list of > &drm_gpuva > + * @va__: &drm_gpuva structure to assign to in each iteration step > + * @vm_bo__: the &drm_gpuvm_bo the &drm_gpuva to walk are associated > with > + * > + * This iterator walks over all &drm_gpuva structures associated > with the > + * &drm_gpuvm_bo.Must hold the ... lock.> + */ > +#define drm_gpuvm_bo_for_each_va(va__, vm_bo__) \ > +???????list_for_each_entry(va__, &(vm_bo)->list.gpuva, gem.entry) > + > +/** > + * drm_gpuvm_bo_for_each_va_safe() - iterator to safely walk over a > list of > + * &drm_gpuva > + * @va__: &drm_gpuva structure to assign to in each iteration step > + * @next__: &next &drm_gpuva to store the next step > + * @vm_bo__: the &drm_gpuvm_bo the &drm_gpuva to walk are associated > with > + * > + * This iterator walks over all &drm_gpuva structures associated > with the > + * &drm_gpuvm_bo. It is implemented with list_for_each_entry_safe(), > hence > + * it is save against removal of elements. > + */ > +#define drm_gpuvm_bo_for_each_va_safe(va__, next__, vm_bo__) \ > +???????list_for_each_entry_safe(va__, next__, &(vm_bo)->list.gpuva, > gem.entry)Same here.> + > ?/** > ? * enum drm_gpuva_op_type - GPU VA operation type > ? * > @@ -643,8 +787,7 @@ drm_gpuvm_prefetch_ops_create(struct drm_gpuvm > *gpuvm, > ???????????????????????????????? u64 addr, u64 range); > ? > ?struct drm_gpuva_ops * > -drm_gpuvm_gem_unmap_ops_create(struct drm_gpuvm *gpuvm, > -????????????????????????????? struct drm_gem_object *obj); > +drm_gpuvm_bo_unmap_ops_create(struct drm_gpuvm_bo *vm_bo); > ? > ?void drm_gpuva_ops_free(struct drm_gpuvm *gpuvm, > ????????????????????????struct drm_gpuva_ops *ops); > @@ -688,6 +831,30 @@ struct drm_gpuvm_ops { > ???????? */ > ????????void (*op_free)(struct drm_gpuva_op *op); > ? > +???????/** > +??????? * @vm_bo_alloc: called when the &drm_gpuvm allocates > +??????? * a struct drm_gpuvm_bo > +??????? * > +??????? * Some drivers may want to embed struct drm_gpuvm_bo into > driver > +??????? * specific structures. By implementing this callback drivers > can > +??????? * allocate memory accordingly. > +??????? * > +??????? * This callback is optional. > +??????? */ > +???????struct drm_gpuvm_bo *(*vm_bo_alloc)(void); > + > +???????/** > +??????? * @vm_bo_free: called when the &drm_gpuvm frees a > +??????? * struct drm_gpuvm_bo > +??????? * > +??????? * Some drivers may want to embed struct drm_gpuvm_bo into > driver > +??????? * specific structures. By implementing this callback drivers > can > +??????? * free the previously allocated memory accordingly. > +??????? * > +??????? * This callback is optional. > +??????? */ > +???????void (*vm_bo_free)(struct drm_gpuvm_bo *vm_bo); > + > ????????/** > ???????? * @sm_step_map: called from &drm_gpuvm_sm_map to finally > insert the > ???????? * mapping once all previous steps were completedThanks, Thomas
Thomas Hellström
2023-Oct-13 12:33 UTC
[Nouveau] [PATCH drm-misc-next v6 3/6] drm/gpuvm: add an abstraction for a VM / BO combination
On Mon, 2023-10-09 at 01:32 +0200, Danilo Krummrich wrote:> Add an abstraction layer between the drm_gpuva mappings of a > particular > drm_gem_object and this GEM object itself. The abstraction represents > a > combination of a drm_gem_object and drm_gpuvm. The drm_gem_object > holds > a list of drm_gpuvm_bo structures (the structure representing this > abstraction), while each drm_gpuvm_bo contains list of mappings of > this > GEM object. > > This has multiple advantages: > > 1) We can use the drm_gpuvm_bo structure to attach it to various > lists > ?? of the drm_gpuvm. This is useful for tracking external and evicted > ?? objects per VM, which is introduced in subsequent patches. > > 2) Finding mappings of a certain drm_gem_object mapped in a certain > ?? drm_gpuvm becomes much cheaper. > > 3) Drivers can derive and extend the structure to easily represent > ?? driver specific states of a BO for a certain GPUVM. > > The idea of this abstraction was taken from amdgpu, hence the credit > for > this idea goes to the developers of amdgpu. > > Cc: Christian K?nig <christian.koenig at amd.com> > Signed-off-by: Danilo Krummrich <dakr at redhat.com> > --- > ?drivers/gpu/drm/drm_gpuvm.c??????????? | 332 +++++++++++++++++++++-- > -- > ?drivers/gpu/drm/nouveau/nouveau_uvmm.c |? 64 +++-- > ?include/drm/drm_gem.h????????????????? |? 32 +-- > ?include/drm/drm_gpuvm.h??????????????? | 177 ++++++++++++- > ?4 files changed, 521 insertions(+), 84 deletions(-)Forgot to mention, there are a couple of checkpatch.pl --strict issues with this patch that might need looking at. Thanks, Thomas