[PATCH drm-next 03/14] drm: manager to keep track of GPUs VA mappings
Danilo Krummrich
dakr at redhat.com
Wed Jan 18 06:12:45 UTC 2023
This adds the infrastructure for a manager implementation to keep track
of GPU virtual address (VA) mappings.
New UAPIs, motivated by Vulkan sparse memory bindings graphics drivers
start implementing, allow userspace applications to request multiple and
arbitrary GPU VA mappings of buffer objects. The DRM GPU VA manager is
intended to serve the following purposes in this context.
1) Provide a dedicated range allocator to track GPU VA allocations and
mappings, making use of the drm_mm range allocator.
2) Generically connect GPU VA mappings to their backing buffers, in
particular DRM GEM objects.
3) Provide a common implementation to perform more complex mapping
operations on the GPU VA space. In particular splitting and merging
of GPU VA mappings, e.g. for intersecting mapping requests or partial
unmap requests.
Idea-suggested-by: Dave Airlie <airlied at redhat.com>
Signed-off-by: Danilo Krummrich <dakr at redhat.com>
---
Documentation/gpu/drm-mm.rst | 31 +
drivers/gpu/drm/Makefile | 1 +
drivers/gpu/drm/drm_gem.c | 3 +
drivers/gpu/drm/drm_gpuva_mgr.c | 1323 +++++++++++++++++++++++++++++++
include/drm/drm_drv.h | 6 +
include/drm/drm_gem.h | 75 ++
include/drm/drm_gpuva_mgr.h | 527 ++++++++++++
7 files changed, 1966 insertions(+)
create mode 100644 drivers/gpu/drm/drm_gpuva_mgr.c
create mode 100644 include/drm/drm_gpuva_mgr.h
diff --git a/Documentation/gpu/drm-mm.rst b/Documentation/gpu/drm-mm.rst
index a52e6f4117d6..c9f120cfe730 100644
--- a/Documentation/gpu/drm-mm.rst
+++ b/Documentation/gpu/drm-mm.rst
@@ -466,6 +466,37 @@ DRM MM Range Allocator Function References
.. kernel-doc:: drivers/gpu/drm/drm_mm.c
:export:
+DRM GPU VA Manager
+==================
+
+Overview
+--------
+
+.. kernel-doc:: drivers/gpu/drm/drm_gpuva_mgr.c
+ :doc: Overview
+
+Split and Merge
+---------------
+
+.. kernel-doc:: drivers/gpu/drm/drm_gpuva_mgr.c
+ :doc: Split and Merge
+
+Locking
+-------
+
+.. kernel-doc:: drivers/gpu/drm/drm_gpuva_mgr.c
+ :doc: Locking
+
+
+DRM GPU VA Manager Function References
+--------------------------------------
+
+.. kernel-doc:: include/drm/drm_gpuva_mgr.h
+ :internal:
+
+.. kernel-doc:: drivers/gpu/drm/drm_gpuva_mgr.c
+ :export:
+
DRM Buddy Allocator
===================
diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile
index 4fe190aee584..de2ffca3b6e4 100644
--- a/drivers/gpu/drm/Makefile
+++ b/drivers/gpu/drm/Makefile
@@ -45,6 +45,7 @@ drm-y := \
drm_vblank.o \
drm_vblank_work.o \
drm_vma_manager.o \
+ drm_gpuva_mgr.o \
drm_writeback.o
drm-$(CONFIG_DRM_LEGACY) += \
drm_agpsupport.o \
diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c
index 59a0bb5ebd85..65115fe88627 100644
--- a/drivers/gpu/drm/drm_gem.c
+++ b/drivers/gpu/drm/drm_gem.c
@@ -164,6 +164,9 @@ void drm_gem_private_object_init(struct drm_device *dev,
if (!obj->resv)
obj->resv = &obj->_resv;
+ if (drm_core_check_feature(dev, DRIVER_GEM_GPUVA))
+ drm_gem_gpuva_init(obj);
+
drm_vma_node_reset(&obj->vma_node);
INIT_LIST_HEAD(&obj->lru_node);
}
diff --git a/drivers/gpu/drm/drm_gpuva_mgr.c b/drivers/gpu/drm/drm_gpuva_mgr.c
new file mode 100644
index 000000000000..e665f642689d
--- /dev/null
+++ b/drivers/gpu/drm/drm_gpuva_mgr.c
@@ -0,0 +1,1323 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2022 Red Hat.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors:
+ * Danilo Krummrich <dakr at redhat.com>
+ *
+ */
+
+#include <drm/drm_gem.h>
+#include <drm/drm_gpuva_mgr.h>
+
+/**
+ * DOC: Overview
+ *
+ * The DRM GPU VA Manager, represented by struct drm_gpuva_manager keeps track
+ * of a GPU's virtual address (VA) space and manages the corresponding virtual
+ * mappings represented by &drm_gpuva objects. It also keeps track of the
+ * mapping's backing &drm_gem_object buffers.
+ *
+ * &drm_gem_object buffers maintain a list (and a corresponding list lock) of
+ * &drm_gpuva objects representing all existent GPU VA mappings using this
+ * &drm_gem_object as backing buffer.
+ *
+ * A GPU VA mapping can only be created within a previously allocated
+ * &drm_gpuva_region, which represents a reserved portion of the GPU VA space.
+ * GPU VA mappings are not allowed to span over a &drm_gpuva_region's boundary.
+ *
+ * GPU VA regions can also be flagged as sparse, which allows drivers to create
+ * sparse mappings for a whole GPU VA region in order to support Vulkan
+ * 'Sparse Resources'.
+ *
+ * The GPU VA manager internally uses the &drm_mm range allocator to manage the
+ * &drm_gpuva mappings and the &drm_gpuva_regions within a GPU's virtual address
+ * space.
+ *
+ * Besides the GPU VA space regions (&drm_gpuva_region) allocated by a driver
+ * the &drm_gpuva_manager contains a special region representing the portion of
+ * VA space reserved by the kernel. This node is initialized together with the
+ * GPU VA manager instance and removed when the GPU VA manager is destroyed.
+ *
+ * In a typical application drivers would embed struct drm_gpuva_manager,
+ * struct drm_gpuva_region and struct drm_gpuva within their own driver
+ * specific structures, there won't be any memory allocations of it's own nor
+ * memory allocations of &drm_gpuva or &drm_gpuva_region entries.
+ */
+
+/**
+ * DOC: Split and Merge
+ *
+ * The DRM GPU VA manager also provides an algorithm implementing splitting and
+ * merging of existent GPU VA mappings with the ones that are requested to be
+ * mapped or unmapped. This feature is required by the Vulkan API to implement
+ * Vulkan 'Sparse Memory Bindings' - drivers UAPIs often refer to this as
+ * VM BIND.
+ *
+ * Drivers can call drm_gpuva_sm_map_ops_create() to obtain a list of map, unmap
+ * and remap operations for a given newly requested mapping. This list
+ * represents the set of operations to execute in order to integrate the new
+ * mapping cleanly into the current state of the GPU VA space.
+ *
+ * Depending on how the new GPU VA mapping intersects with the existent mappings
+ * of the GPU VA space the &drm_gpuva_ops contain an arbitrary amount of unmap
+ * operations, a maximum of two remap operations and a single map operation.
+ * The set of operations can also be empty if no operation is required, e.g. if
+ * the requested mapping already exists in the exact same way.
+ *
+ * The single map operation, if existent, represents the original map operation
+ * requested by the caller. Please note that this operation might be altered
+ * comparing it with the original map operation, e.g. because it was merged with
+ * an already existent mapping. Hence, drivers must execute this map operation
+ * instead of the original one they passed to drm_gpuva_sm_map_ops_create().
+ *
+ * &drm_gpuva_op_unmap contains a 'keep' field, which indicates whether the
+ * &drm_gpuva to unmap is physically contiguous with the original mapping
+ * request. Optionally, if 'keep' is set, drivers may keep the actual page table
+ * entries for this &drm_gpuva, adding the missing page table entries only and
+ * update the &drm_gpuva_manager's view of things accordingly.
+ *
+ * Drivers may do the same optimization, namely delta page table updates, also
+ * for remap operations. This is possible since &drm_gpuva_op_remap consists of
+ * one unmap operation and one or two map operations, such that drivers can
+ * derive the page table update delta accordingly.
+ *
+ * Note that there can't be more than two existent mappings to split up, one at
+ * the beginning and one at the end of the new mapping, hence there is a
+ * maximum of two remap operations.
+ *
+ * Generally, the DRM GPU VA manager never merges mappings across the
+ * boundaries of &drm_gpuva_regions. This is the case since merging between
+ * GPU VA regions would result into unmap and map operations to be issued for
+ * both regions involved although the original mapping request was referred to
+ * one specific GPU VA region only. Since the other GPU VA region, the one not
+ * explicitly requested to be altered, might be in use by the GPU, we are not
+ * allowed to issue any map/unmap operations for this region.
+ *
+ * Note that before calling drm_gpuva_sm_map_ops_create() again with another
+ * mapping request it is necessary to update the &drm_gpuva_manager's view of
+ * the GPU VA space. The previously obtained operations must be either fully
+ * processed or completely abandoned.
+ *
+ * To update the &drm_gpuva_manager's view of the GPU VA space
+ * drm_gpuva_insert(), drm_gpuva_destroy_locked() and/or
+ * drm_gpuva_destroy_unlocked() should be used.
+ *
+ * Analogue to drm_gpuva_sm_map_ops_create() drm_gpuva_sm_unmap_ops_create()
+ * provides drivers a the list of operations to be executed in order to unmap
+ * a range of GPU VA space. The logic behind this functions is way simpler
+ * though: For all existent mappings enclosed by the given range unmap
+ * operations are created. For mappings which are only partically located within
+ * the given range, remap operations are created such that those mappings are
+ * split up and re-mapped partically.
+ *
+ * The following paragraph depicts the basic constellations of existent GPU VA
+ * mappings, a newly requested mapping and the resulting mappings as implemented
+ * by drm_gpuva_sm_map_ops_create() - it doesn't cover arbitrary combinations
+ * of those constellations.
+ *
+ * ::
+ *
+ * 1) Existent mapping is kept.
+ * ----------------------------
+ *
+ * 0 a 1
+ * old: |-----------| (bo_offset=n)
+ *
+ * 0 a 1
+ * req: |-----------| (bo_offset=n)
+ *
+ * 0 a 1
+ * new: |-----------| (bo_offset=n)
+ *
+ *
+ * 2) Existent mapping is replaced.
+ * --------------------------------
+ *
+ * 0 a 1
+ * old: |-----------| (bo_offset=n)
+ *
+ * 0 a 1
+ * req: |-----------| (bo_offset=m)
+ *
+ * 0 a 1
+ * new: |-----------| (bo_offset=m)
+ *
+ *
+ * 3) Existent mapping is replaced.
+ * --------------------------------
+ *
+ * 0 a 1
+ * old: |-----------| (bo_offset=n)
+ *
+ * 0 b 1
+ * req: |-----------| (bo_offset=n)
+ *
+ * 0 b 1
+ * new: |-----------| (bo_offset=n)
+ *
+ *
+ * 4) Existent mapping is replaced.
+ * --------------------------------
+ *
+ * 0 a 1
+ * old: |-----| (bo_offset=n)
+ *
+ * 0 a 2
+ * req: |-----------| (bo_offset=n)
+ *
+ * 0 a 2
+ * new: |-----------| (bo_offset=n)
+ *
+ * Note: We expect to see the same result for a request with a different bo
+ * and/or bo_offset.
+ *
+ *
+ * 5) Existent mapping is split.
+ * -----------------------------
+ *
+ * 0 a 2
+ * old: |-----------| (bo_offset=n)
+ *
+ * 0 b 1
+ * req: |-----| (bo_offset=n)
+ *
+ * 0 b 1 a' 2
+ * new: |-----|-----| (b.bo_offset=n, a.bo_offset=n+1)
+ *
+ * Note: We expect to see the same result for a request with a different bo
+ * and/or non-contiguous bo_offset.
+ *
+ *
+ * 6) Existent mapping is kept.
+ * ----------------------------
+ *
+ * 0 a 2
+ * old: |-----------| (bo_offset=n)
+ *
+ * 0 a 1
+ * req: |-----| (bo_offset=n)
+ *
+ * 0 a 2
+ * new: |-----------| (bo_offset=n)
+ *
+ *
+ * 7) Existent mapping is split.
+ * -----------------------------
+ *
+ * 0 a 2
+ * old: |-----------| (bo_offset=n)
+ *
+ * 1 b 2
+ * req: |-----| (bo_offset=m)
+ *
+ * 0 a 1 b 2
+ * new: |-----|-----| (a.bo_offset=n,b.bo_offset=m)
+ *
+ *
+ * 8) Existent mapping is kept.
+ * ----------------------------
+ *
+ * 0 a 2
+ * old: |-----------| (bo_offset=n)
+ *
+ * 1 a 2
+ * req: |-----| (bo_offset=n+1)
+ *
+ * 0 a 2
+ * new: |-----------| (bo_offset=n)
+ *
+ *
+ * 9) Existent mapping is split.
+ * -----------------------------
+ *
+ * 0 a 2
+ * old: |-----------| (bo_offset=n)
+ *
+ * 1 b 3
+ * req: |-----------| (bo_offset=m)
+ *
+ * 0 a 1 b 3
+ * new: |-----|-----------| (a.bo_offset=n,b.bo_offset=m)
+ *
+ *
+ * 10) Existent mapping is merged.
+ * -------------------------------
+ *
+ * 0 a 2
+ * old: |-----------| (bo_offset=n)
+ *
+ * 1 a 3
+ * req: |-----------| (bo_offset=n+1)
+ *
+ * 0 a 3
+ * new: |-----------------| (bo_offset=n)
+ *
+ *
+ * 11) Existent mapping is split.
+ * ------------------------------
+ *
+ * 0 a 3
+ * old: |-----------------| (bo_offset=n)
+ *
+ * 1 b 2
+ * req: |-----| (bo_offset=m)
+ *
+ * 0 a 1 b 2 a' 3
+ * new: |-----|-----|-----| (a.bo_offset=n,b.bo_offset=m,a'.bo_offset=n+2)
+ *
+ *
+ * 12) Existent mapping is kept.
+ * -----------------------------
+ *
+ * 0 a 3
+ * old: |-----------------| (bo_offset=n)
+ *
+ * 1 a 2
+ * req: |-----| (bo_offset=n+1)
+ *
+ * 0 a 3
+ * old: |-----------------| (bo_offset=n)
+ *
+ *
+ * 13) Existent mapping is replaced.
+ * ---------------------------------
+ *
+ * 1 a 2
+ * old: |-----| (bo_offset=n)
+ *
+ * 0 a 2
+ * req: |-----------| (bo_offset=n)
+ *
+ * 0 a 2
+ * new: |-----------| (bo_offset=n)
+ *
+ * Note: We expect to see the same result for a request with a different bo
+ * and/or non-contiguous bo_offset.
+ *
+ *
+ * 14) Existent mapping is replaced.
+ * ---------------------------------
+ *
+ * 1 a 2
+ * old: |-----| (bo_offset=n)
+ *
+ * 0 a 3
+ * req: |----------------| (bo_offset=n)
+ *
+ * 0 a 3
+ * new: |----------------| (bo_offset=n)
+ *
+ * Note: We expect to see the same result for a request with a different bo
+ * and/or non-contiguous bo_offset.
+ *
+ *
+ * 15) Existent mapping is split.
+ * ------------------------------
+ *
+ * 1 a 3
+ * old: |-----------| (bo_offset=n)
+ *
+ * 0 b 2
+ * req: |-----------| (bo_offset=m)
+ *
+ * 0 b 2 a' 3
+ * new: |-----------|-----| (b.bo_offset=m,a.bo_offset=n+2)
+ *
+ *
+ * 16) Existent mappings are merged.
+ * ---------------------------------
+ *
+ * 0 a 1
+ * old: |-----------| (bo_offset=n)
+ *
+ * 2 a 3
+ * old': |-----------| (bo_offset=n+2)
+ *
+ * 1 a 2
+ * req: |-----------| (bo_offset=n+1)
+ *
+ * a
+ * new: |----------------------------------| (bo_offset=n)
+ */
+
+/**
+ * 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, destroying and iterating
+ * &drm_gpuva and &drm_gpuva_region objects as well as generating split and merge
+ * operations.
+ *
+ * The GPU VA manager does take care of the locking of the backing
+ * &drm_gem_object buffers GPU VA lists though, unless the provided functions
+ * documentation claims otherwise.
+ */
+
+/**
+ * drm_gpuva_manager_init - initialize a &drm_gpuva_manager
+ * @mgr: pointer to the &drm_gpuva_manager to initialize
+ * @name: the name of the GPU VA space
+ * @start_offset: the start offset of the GPU VA space
+ * @range: the size of the GPU VA space
+ * @reserve_offset: the start of the kernel reserved GPU VA area
+ * @reserve_range: the size of the kernel reserved GPU VA area
+ *
+ * The &drm_gpuva_manager must be initialized with this function before use.
+ *
+ * Note that @mgr must be cleared to 0 before calling this function. The given
+ * &name is expected to be managed by the surrounding driver structures.
+ */
+void
+drm_gpuva_manager_init(struct drm_gpuva_manager *mgr,
+ const char *name,
+ u64 start_offset, u64 range,
+ u64 reserve_offset, u64 reserve_range)
+{
+ drm_mm_init(&mgr->va_mm, start_offset, range);
+ drm_mm_init(&mgr->region_mm, start_offset, range);
+
+ mgr->mm_start = start_offset;
+ mgr->mm_range = range;
+
+ mgr->name = name ? name : "unknown";
+
+ memset(&mgr->kernel_alloc_node, 0, sizeof(struct drm_mm_node));
+ mgr->kernel_alloc_node.start = reserve_offset;
+ mgr->kernel_alloc_node.size = reserve_range;
+ drm_mm_reserve_node(&mgr->region_mm, &mgr->kernel_alloc_node);
+}
+EXPORT_SYMBOL(drm_gpuva_manager_init);
+
+/**
+ * drm_gpuva_manager_destroy - cleanup a &drm_gpuva_manager
+ * @mgr: pointer to the &drm_gpuva_manager to clean up
+ *
+ * Note that it is a bug to call this function on a manager that still
+ * holds GPU VA mappings.
+ */
+void
+drm_gpuva_manager_destroy(struct drm_gpuva_manager *mgr)
+{
+ mgr->name = NULL;
+ drm_mm_remove_node(&mgr->kernel_alloc_node);
+ drm_mm_takedown(&mgr->va_mm);
+ drm_mm_takedown(&mgr->region_mm);
+}
+EXPORT_SYMBOL(drm_gpuva_manager_destroy);
+
+static struct drm_gpuva_region *
+drm_gpuva_in_region(struct drm_gpuva_manager *mgr, u64 addr, u64 range)
+{
+ struct drm_gpuva_region *reg;
+
+ /* Find the VA region the requested range is strictly enclosed by. */
+ drm_gpuva_for_each_region_in_range(reg, mgr, addr, addr + range) {
+ if (reg->node.start <= addr &&
+ reg->node.start + reg->node.size >= addr + range &&
+ ®->node != &mgr->kernel_alloc_node)
+ return reg;
+ }
+
+ return NULL;
+}
+
+static bool
+drm_gpuva_in_any_region(struct drm_gpuva_manager *mgr, u64 addr, u64 range)
+{
+ return !!drm_gpuva_in_region(mgr, addr, range);
+}
+
+/**
+ * drm_gpuva_insert - insert a &drm_gpuva
+ * @mgr: the &drm_gpuva_manager to insert the &drm_gpuva in
+ * @va: the &drm_gpuva to insert
+ * @addr: the start address of the GPU VA
+ * @range: the range of the GPU VA
+ *
+ * Insert a &drm_gpuva with a given address and range into a
+ * &drm_gpuva_manager.
+ *
+ * The function assumes the caller does not hold the &drm_gem_object's
+ * GPU VA list mutex.
+ *
+ * Returns: 0 on success, negative error code on failure.
+ */
+int
+drm_gpuva_insert(struct drm_gpuva_manager *mgr,
+ struct drm_gpuva *va,
+ u64 addr, u64 range)
+{
+ struct drm_gpuva_region *reg;
+ int ret;
+
+ if (!va->gem.obj)
+ return -EINVAL;
+
+ reg = drm_gpuva_in_region(mgr, addr, range);
+ if (!reg)
+ return -EINVAL;
+
+ ret = drm_mm_insert_node_in_range(&mgr->va_mm, &va->node,
+ range, 0,
+ 0, addr,
+ addr + range,
+ DRM_MM_INSERT_LOW|DRM_MM_INSERT_ONCE);
+ if (ret)
+ return ret;
+
+ va->mgr = mgr;
+ va->region = reg;
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_gpuva_insert);
+
+/**
+ * drm_gpuva_link_locked - link a &drm_gpuva
+ * @va: the &drm_gpuva to link
+ *
+ * This adds the given &va to the GPU VA list of the &drm_gem_object it is
+ * associated with.
+ *
+ * The function assumes the caller already holds the &drm_gem_object's
+ * GPU VA list mutex.
+ */
+void
+drm_gpuva_link_locked(struct drm_gpuva *va)
+{
+ lockdep_assert_held(&va->gem.obj->gpuva.mutex);
+ list_add_tail(&va->head, &va->gem.obj->gpuva.list);
+}
+EXPORT_SYMBOL(drm_gpuva_link_locked);
+
+/**
+ * drm_gpuva_link_unlocked - unlink a &drm_gpuva
+ * @va: the &drm_gpuva to unlink
+ *
+ * This adds the given &va to the GPU VA list of the &drm_gem_object it is
+ * associated with.
+ *
+ * The function assumes the caller does not hold the &drm_gem_object's
+ * GPU VA list mutex.
+ */
+void
+drm_gpuva_link_unlocked(struct drm_gpuva *va)
+{
+ drm_gem_gpuva_lock(va->gem.obj);
+ drm_gpuva_link_locked(va);
+ drm_gem_gpuva_unlock(va->gem.obj);
+}
+EXPORT_SYMBOL(drm_gpuva_link_unlocked);
+
+/**
+ * drm_gpuva_unlink_locked - unlink a &drm_gpuva
+ * @va: the &drm_gpuva to unlink
+ *
+ * This removes the given &va from the GPU VA list of the &drm_gem_object it is
+ * associated with.
+ *
+ * The function assumes the caller already holds the &drm_gem_object's
+ * GPU VA list mutex.
+ */
+void
+drm_gpuva_unlink_locked(struct drm_gpuva *va)
+{
+ lockdep_assert_held(&va->gem.obj->gpuva.mutex);
+ list_del_init(&va->head);
+}
+EXPORT_SYMBOL(drm_gpuva_unlink_locked);
+
+/**
+ * drm_gpuva_unlink_unlocked - unlink a &drm_gpuva
+ * @va: the &drm_gpuva to unlink
+ *
+ * This removes the given &va from the GPU VA list of the &drm_gem_object it is
+ * associated with.
+ *
+ * The function assumes the caller does not hold the &drm_gem_object's
+ * GPU VA list mutex.
+ */
+void
+drm_gpuva_unlink_unlocked(struct drm_gpuva *va)
+{
+ drm_gem_gpuva_lock(va->gem.obj);
+ drm_gpuva_unlink_locked(va);
+ drm_gem_gpuva_unlock(va->gem.obj);
+}
+EXPORT_SYMBOL(drm_gpuva_unlink_unlocked);
+
+/**
+ * drm_gpuva_destroy_locked - destroy a &drm_gpuva
+ * @va: the &drm_gpuva to destroy
+ *
+ * This removes the given &va from GPU VA list of the &drm_gem_object it is
+ * associated with and removes it from the underlaying range allocator.
+ *
+ * The function assumes the caller already holds the &drm_gem_object's
+ * GPU VA list mutex.
+ */
+void
+drm_gpuva_destroy_locked(struct drm_gpuva *va)
+{
+ lockdep_assert_held(&va->gem.obj->gpuva.mutex);
+
+ list_del(&va->head);
+ drm_mm_remove_node(&va->node);
+}
+EXPORT_SYMBOL(drm_gpuva_destroy_locked);
+
+/**
+ * drm_gpuva_destroy_unlocked - destroy a &drm_gpuva
+ * @va: the &drm_gpuva to destroy
+ *
+ * This removes the given &va from GPU VA list of the &drm_gem_object it is
+ * associated with and removes it from the underlaying range allocator.
+ *
+ * The function assumes the caller does not hold the &drm_gem_object's
+ * GPU VA list mutex.
+ */
+void
+drm_gpuva_destroy_unlocked(struct drm_gpuva *va)
+{
+ drm_gem_gpuva_lock(va->gem.obj);
+ list_del(&va->head);
+ drm_gem_gpuva_unlock(va->gem.obj);
+
+ drm_mm_remove_node(&va->node);
+}
+EXPORT_SYMBOL(drm_gpuva_destroy_unlocked);
+
+/**
+ * drm_gpuva_find - find a &drm_gpuva
+ * @mgr: the &drm_gpuva_manager to search in
+ * @addr: the &drm_gpuvas address
+ * @range: the &drm_gpuvas range
+ *
+ * Returns: the &drm_gpuva at a given &addr and with a given &range
+ */
+struct drm_gpuva *
+drm_gpuva_find(struct drm_gpuva_manager *mgr,
+ u64 addr, u64 range)
+{
+ struct drm_gpuva *va;
+
+ drm_gpuva_for_each_va_in_range(va, mgr, addr, range) {
+ if (va->node.start == addr &&
+ va->node.size == range)
+ return va;
+ }
+
+ return NULL;
+}
+EXPORT_SYMBOL(drm_gpuva_find);
+
+/**
+ * drm_gpuva_find_prev - find the &drm_gpuva before the given address
+ * @mgr: the &drm_gpuva_manager to search in
+ * @start: the given GPU VA's start address
+ *
+ * Find the adjacent &drm_gpuva before the GPU VA with given &start address.
+ *
+ * Note that if there is any free space between the GPU VA mappings no mapping
+ * is returned.
+ *
+ * Returns: a pointer to the found &drm_gpuva or NULL if none was found
+ */
+struct drm_gpuva *
+drm_gpuva_find_prev(struct drm_gpuva_manager *mgr, u64 start)
+{
+ struct drm_mm_node *node;
+
+ if (start <= mgr->mm_start ||
+ start > (mgr->mm_start + mgr->mm_range))
+ return NULL;
+
+ node = __drm_mm_interval_first(&mgr->va_mm, start - 1, start);
+ if (node == &mgr->va_mm.head_node)
+ return NULL;
+
+ return (struct drm_gpuva *)node;
+}
+EXPORT_SYMBOL(drm_gpuva_find_prev);
+
+/**
+ * drm_gpuva_find_next - find the &drm_gpuva after the given address
+ * @mgr: the &drm_gpuva_manager to search in
+ * @end: the given GPU VA's end address
+ *
+ * Find the adjacent &drm_gpuva after the GPU VA with given &end address.
+ *
+ * Note that if there is any free space between the GPU VA mappings no mapping
+ * is returned.
+ *
+ * Returns: a pointer to the found &drm_gpuva or NULL if none was found
+ */
+struct drm_gpuva *
+drm_gpuva_find_next(struct drm_gpuva_manager *mgr, u64 end)
+{
+ struct drm_mm_node *node;
+
+ if (end < mgr->mm_start ||
+ end >= (mgr->mm_start + mgr->mm_range))
+ return NULL;
+
+ node = __drm_mm_interval_first(&mgr->va_mm, end, end + 1);
+ if (node == &mgr->va_mm.head_node)
+ return NULL;
+
+ return (struct drm_gpuva *)node;
+}
+EXPORT_SYMBOL(drm_gpuva_find_next);
+
+/**
+ * drm_gpuva_region_insert - insert a &drm_gpuva_region
+ * @mgr: the &drm_gpuva_manager to insert the &drm_gpuva in
+ * @reg: the &drm_gpuva_region to insert
+ * @addr: the start address of the GPU VA
+ * @range: the range of the GPU VA
+ *
+ * Insert a &drm_gpuva_region with a given address and range into a
+ * &drm_gpuva_manager.
+ *
+ * Returns: 0 on success, negative error code on failure.
+ */
+int
+drm_gpuva_region_insert(struct drm_gpuva_manager *mgr,
+ struct drm_gpuva_region *reg,
+ u64 addr, u64 range)
+{
+ int ret;
+
+ ret = drm_mm_insert_node_in_range(&mgr->region_mm, ®->node,
+ range, 0,
+ 0, addr,
+ addr + range,
+ DRM_MM_INSERT_LOW|
+ DRM_MM_INSERT_ONCE);
+ if (ret)
+ return ret;
+
+ reg->mgr = mgr;
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_gpuva_region_insert);
+
+/**
+ * drm_gpuva_region_destroy - destroy a &drm_gpuva_region
+ * @mgr: the &drm_gpuva_manager holding the region
+ * @reg: the &drm_gpuva to destroy
+ *
+ * This removes the given ® from the underlaying range allocator.
+ */
+void
+drm_gpuva_region_destroy(struct drm_gpuva_manager *mgr,
+ struct drm_gpuva_region *reg)
+{
+ struct drm_gpuva *va;
+
+ drm_gpuva_for_each_va_in_range(va, mgr,
+ reg->node.start,
+ reg->node.size) {
+ WARN(1, "GPU VA region must be empty on destroy.\n");
+ return;
+ }
+
+ if (®->node == &mgr->kernel_alloc_node) {
+ WARN(1, "Can't destroy kernel reserved region.\n");
+ return;
+ }
+
+ drm_mm_remove_node(®->node);
+}
+EXPORT_SYMBOL(drm_gpuva_region_destroy);
+
+/**
+ * drm_gpuva_region_find - find a &drm_gpuva_region
+ * @mgr: the &drm_gpuva_manager to search in
+ * @addr: the &drm_gpuva_regions address
+ * @range: the &drm_gpuva_regions range
+ *
+ * Returns: the &drm_gpuva_region at a given &addr and with a given &range
+ */
+struct drm_gpuva_region *
+drm_gpuva_region_find(struct drm_gpuva_manager *mgr,
+ u64 addr, u64 range)
+{
+ struct drm_gpuva_region *reg;
+
+ drm_gpuva_for_each_region_in_range(reg, mgr, addr, addr + range)
+ if (reg->node.start == addr &&
+ reg->node.size == range)
+ return reg;
+
+ return NULL;
+}
+EXPORT_SYMBOL(drm_gpuva_region_find);
+
+static int
+gpuva_op_map_new(struct drm_gpuva_op **pop,
+ u64 addr, u64 range,
+ struct drm_gem_object *obj, u64 offset)
+{
+ struct drm_gpuva_op *op;
+
+ op = *pop = kzalloc(sizeof(*op), GFP_KERNEL);
+ if (!op)
+ return -ENOMEM;
+
+ op->op = DRM_GPUVA_OP_MAP;
+ op->map.va.addr = addr;
+ op->map.va.range = range;
+ op->map.gem.obj = obj;
+ op->map.gem.offset = offset;
+
+ return 0;
+}
+
+static int
+gpuva_op_remap_new(struct drm_gpuva_op **pop,
+ struct drm_gpuva_op_map *prev,
+ struct drm_gpuva_op_map *next,
+ struct drm_gpuva_op_unmap *unmap)
+{
+ struct drm_gpuva_op *op;
+ struct drm_gpuva_op_remap *r;
+
+ op = *pop = kzalloc(sizeof(*op), GFP_KERNEL);
+ if (!op)
+ return -ENOMEM;
+
+ op->op = DRM_GPUVA_OP_REMAP;
+ r = &op->remap;
+
+ if (prev) {
+ r->prev = kmemdup(prev, sizeof(*prev), GFP_KERNEL);
+ if (!r->prev)
+ goto err_free_op;
+ }
+
+ if (next) {
+ r->next = kmemdup(next, sizeof(*next), GFP_KERNEL);
+ if (!r->next)
+ goto err_free_prev;
+ }
+
+ r->unmap = kmemdup(unmap, sizeof(*unmap), GFP_KERNEL);
+ if (!r->unmap)
+ goto err_free_next;
+
+ return 0;
+
+err_free_next:
+ if (next)
+ kfree(r->next);
+err_free_prev:
+ if (prev)
+ kfree(r->prev);
+err_free_op:
+ kfree(op);
+ *pop = NULL;
+
+ return -ENOMEM;
+}
+
+static int
+gpuva_op_unmap_new(struct drm_gpuva_op **pop,
+ struct drm_gpuva *va, bool merge)
+{
+ struct drm_gpuva_op *op;
+
+ op = *pop = kzalloc(sizeof(*op), GFP_KERNEL);
+ if (!op)
+ return -ENOMEM;
+
+ op->op = DRM_GPUVA_OP_UNMAP;
+ op->unmap.va = va;
+ op->unmap.keep = merge;
+
+ return 0;
+}
+
+#define op_map_new_to_list(_ops, _addr, _range, \
+ _obj, _offset) \
+do { \
+ struct drm_gpuva_op *op; \
+ \
+ ret = gpuva_op_map_new(&op, _addr, _range, \
+ _obj, _offset); \
+ if (ret) \
+ goto err_free_ops; \
+ \
+ list_add_tail(&op->entry, _ops); \
+} while (0)
+
+#define op_remap_new_to_list(_ops, _prev, _next, \
+ _unmap) \
+do { \
+ struct drm_gpuva_op *op; \
+ \
+ ret = gpuva_op_remap_new(&op, _prev, _next, \
+ _unmap); \
+ if (ret) \
+ goto err_free_ops; \
+ \
+ list_add_tail(&op->entry, _ops); \
+} while (0)
+
+#define op_unmap_new_to_list(_ops, _gpuva, _merge) \
+do { \
+ struct drm_gpuva_op *op; \
+ \
+ ret = gpuva_op_unmap_new(&op, _gpuva, _merge); \
+ if (ret) \
+ goto err_free_ops; \
+ \
+ list_add_tail(&op->entry, _ops); \
+} while (0)
+
+/**
+ * drm_gpuva_sm_map_ops_create - creates the &drm_gpuva_ops to split and merge
+ * @mgr: the &drm_gpuva_manager representing the GPU VA space
+ * @req_addr: the start address of the new mapping
+ * @req_range: the range of the new mapping
+ * @req_obj: the &drm_gem_object to map
+ * @req_offset: the offset within the &drm_gem_object
+ *
+ * This function creates a list of operations to perform splitting and merging
+ * of existent mapping(s) with the newly requested one.
+ *
+ * The list can be iterated with &drm_gpuva_for_each_op and must be processed
+ * in the given order. It can contain map, unmap and remap operations, but it
+ * also can be empty if no operation is required, e.g. if the requested mapping
+ * already exists is the exact same way.
+ *
+ * There can be an arbitrary amount of unmap operations, a maximum of two remap
+ * operations and a single map operation. The latter one, if existent,
+ * represents the original map operation requested by the caller. Please note
+ * that the map operation might has been modified, e.g. if it was
+ * merged with an existent mapping.
+ *
+ * Note that before calling this function again with another mapping request it
+ * is necessary to update the &drm_gpuva_manager's view of the GPU VA space.
+ * The previously obtained operations must be either processed or abandoned.
+ * To update the &drm_gpuva_manager's view of the GPU VA space
+ * drm_gpuva_insert(), drm_gpuva_destroy_locked() and/or
+ * drm_gpuva_destroy_unlocked() should be used.
+ *
+ * After the caller finished processing the returned &drm_gpuva_ops, they must
+ * be freed with &drm_gpuva_ops_free.
+ *
+ * Returns: a pointer to the &drm_gpuva_ops on success, an ERR_PTR on failure
+ */
+struct drm_gpuva_ops *
+drm_gpuva_sm_map_ops_create(struct drm_gpuva_manager *mgr,
+ u64 req_addr, u64 req_range,
+ struct drm_gem_object *req_obj, u64 req_offset)
+{
+ struct drm_gpuva_ops *ops;
+ struct drm_gpuva *va, *prev = NULL;
+ u64 req_end = req_addr + req_range;
+ bool skip_pmerge = false, skip_nmerge = false;
+ int ret;
+
+ if (!drm_gpuva_in_any_region(mgr, req_addr, req_range))
+ return ERR_PTR(-EINVAL);
+
+ ops = kzalloc(sizeof(*ops), GFP_KERNEL);
+ if (!ops)
+ return ERR_PTR(-ENOMEM);
+
+ INIT_LIST_HEAD(&ops->list);
+
+ drm_gpuva_for_each_va_in_range(va, mgr, req_addr, req_end) {
+ struct drm_gem_object *obj = va->gem.obj;
+ u64 offset = va->gem.offset;
+ u64 addr = va->node.start;
+ u64 range = va->node.size;
+ u64 end = addr + range;
+
+ /* Generally, we want to skip merging with potential mappings
+ * left and right of the requested one when we found a
+ * collision, since merging happens in this loop already.
+ *
+ * However, there is one exception when the requested mapping
+ * spans into a free VM area. If this is the case we might
+ * still hit the boundary of another mapping before and/or
+ * after the free VM area.
+ */
+ skip_pmerge = true;
+ skip_nmerge = true;
+
+ if (addr == req_addr) {
+ bool merge = obj == req_obj &&
+ offset == req_offset;
+ if (end == req_end) {
+ if (merge)
+ goto done;
+
+ op_unmap_new_to_list(&ops->list, va, false);
+ break;
+ }
+
+ if (end < req_end) {
+ skip_nmerge = false;
+ op_unmap_new_to_list(&ops->list, va, merge);
+ goto next;
+ }
+
+ if (end > req_end) {
+ struct drm_gpuva_op_map n = {
+ .va.addr = req_end,
+ .va.range = range - req_range,
+ .gem.obj = obj,
+ .gem.offset = offset + req_range,
+ };
+ struct drm_gpuva_op_unmap u = { .va = va };
+
+ if (merge)
+ goto done;
+
+ op_remap_new_to_list(&ops->list, NULL, &n, &u);
+ break;
+ }
+ } else if (addr < req_addr) {
+ u64 ls_range = req_addr - addr;
+ struct drm_gpuva_op_map p = {
+ .va.addr = addr,
+ .va.range = ls_range,
+ .gem.obj = obj,
+ .gem.offset = offset,
+ };
+ struct drm_gpuva_op_unmap u = { .va = va };
+ bool merge = obj == req_obj &&
+ offset + ls_range == req_offset;
+
+ if (end == req_end) {
+ if (merge)
+ goto done;
+
+ op_remap_new_to_list(&ops->list, &p, NULL, &u);
+ break;
+ }
+
+ if (end < req_end) {
+ u64 new_addr = addr;
+ u64 new_range = req_range + ls_range;
+ u64 new_offset = offset;
+
+ /* We validated that the requested mapping is
+ * within a single VA region already.
+ * Since it overlaps the current mapping (which
+ * can't cross a VA region boundary) we can be
+ * sure that we're still within the boundaries
+ * of the same VA region after merging.
+ */
+ if (merge) {
+ req_offset = new_offset;
+ req_addr = new_addr;
+ req_range = new_range;
+ op_unmap_new_to_list(&ops->list, va, true);
+ goto next;
+ }
+
+ op_remap_new_to_list(&ops->list, &p, NULL, &u);
+ goto next;
+ }
+
+ if (end > req_end) {
+ struct drm_gpuva_op_map n = {
+ .va.addr = req_end,
+ .va.range = end - req_end,
+ .gem.obj = obj,
+ .gem.offset = offset + ls_range +
+ req_range,
+ };
+
+ if (merge)
+ goto done;
+
+ op_remap_new_to_list(&ops->list, &p, &n, &u);
+ break;
+ }
+ } else if (addr > req_addr) {
+ bool merge = obj == req_obj &&
+ offset == req_offset +
+ (addr - req_addr);
+ if (!prev)
+ skip_pmerge = false;
+
+ if (end == req_end) {
+ op_unmap_new_to_list(&ops->list, va, merge);
+ break;
+ }
+
+ if (end < req_end) {
+ skip_nmerge = false;
+ op_unmap_new_to_list(&ops->list, va, merge);
+ goto next;
+ }
+
+ if (end > req_end) {
+ struct drm_gpuva_op_map n = {
+ .va.addr = req_end,
+ .va.range = end - req_end,
+ .gem.obj = obj,
+ .gem.offset = offset + req_end - addr,
+ };
+ struct drm_gpuva_op_unmap u = { .va = va };
+ u64 new_end = end;
+ u64 new_range = new_end - req_addr;
+
+ /* We validated that the requested mapping is
+ * within a single VA region already.
+ * Since it overlaps the current mapping (which
+ * can't cross a VA region boundary) we can be
+ * sure that we're still within the boundaries
+ * of the same VA region after merging.
+ */
+ if (merge) {
+ req_end = new_end;
+ req_range = new_range;
+ op_unmap_new_to_list(&ops->list, va, true);
+ break;
+ }
+
+ op_remap_new_to_list(&ops->list, NULL, &n, &u);
+ break;
+ }
+ }
+next:
+ prev = va;
+ }
+
+ va = skip_pmerge ? NULL : drm_gpuva_find_prev(mgr, req_addr);
+ if (va) {
+ struct drm_gem_object *obj = va->gem.obj;
+ u64 offset = va->gem.offset;
+ u64 addr = va->node.start;
+ u64 range = va->node.size;
+ u64 new_offset = offset;
+ u64 new_addr = addr;
+ u64 new_range = req_range + range;
+ bool merge = obj == req_obj &&
+ offset + range == req_offset;
+
+ /* Don't merge over VA region boundaries. */
+ merge &= drm_gpuva_in_any_region(mgr, new_addr, new_range);
+ if (merge) {
+ op_unmap_new_to_list(&ops->list, va, true);
+
+ req_offset = new_offset;
+ req_addr = new_addr;
+ req_range = new_range;
+ }
+ }
+
+ va = skip_nmerge ? NULL : drm_gpuva_find_next(mgr, req_end);
+ if (va) {
+ struct drm_gem_object *obj = va->gem.obj;
+ u64 offset = va->gem.offset;
+ u64 addr = va->node.start;
+ u64 range = va->node.size;
+ u64 end = addr + range;
+ u64 new_range = req_range + range;
+ u64 new_end = end;
+ bool merge = obj == req_obj &&
+ offset == req_offset + req_range;
+
+ /* Don't merge over VA region boundaries. */
+ merge &= drm_gpuva_in_any_region(mgr, req_addr, new_range);
+ if (merge) {
+ op_unmap_new_to_list(&ops->list, va, true);
+
+ req_range = new_range;
+ req_end = new_end;
+ }
+ }
+
+ op_map_new_to_list(&ops->list,
+ req_addr, req_range,
+ req_obj, req_offset);
+
+done:
+ return ops;
+
+err_free_ops:
+ drm_gpuva_ops_free(ops);
+ return ERR_PTR(ret);
+}
+EXPORT_SYMBOL(drm_gpuva_sm_map_ops_create);
+
+#undef op_map_new_to_list
+#undef op_remap_new_to_list
+#undef op_unmap_new_to_list
+
+/**
+ * drm_gpuva_sm_unmap_ops_create - creates the &drm_gpuva_ops to split on unmap
+ * @mgr: the &drm_gpuva_manager representing the GPU VA space
+ * @req_addr: the start address of the range to unmap
+ * @req_range: the range of the mappings to unmap
+ *
+ * This function creates a list of operations to perform unmapping and, if
+ * required, splitting of the mappings overlapping the unmap range.
+ *
+ * The list can be iterated with &drm_gpuva_for_each_op and must be processed
+ * in the given order. It can contain unmap and remap operations, depending on
+ * whether there are actual overlapping mappings to split.
+ *
+ * There can be an arbitrary amount of unmap operations and a maximum of two
+ * remap operations.
+ *
+ * Note that before calling this function again with another range to unmap it
+ * is necessary to update the &drm_gpuva_manager's view of the GPU VA space.
+ * The previously obtained operations must be processed or abandoned.
+ * To update the &drm_gpuva_manager's view of the GPU VA space
+ * drm_gpuva_insert(), drm_gpuva_destroy_locked() and/or
+ * drm_gpuva_destroy_unlocked() should be used.
+ *
+ * After the caller finished processing the returned &drm_gpuva_ops, they must
+ * be freed with &drm_gpuva_ops_free.
+ *
+ * Returns: a pointer to the &drm_gpuva_ops on success, an ERR_PTR on failure
+ */
+struct drm_gpuva_ops *
+drm_gpuva_sm_unmap_ops_create(struct drm_gpuva_manager *mgr,
+ u64 req_addr, u64 req_range)
+{
+ struct drm_gpuva_ops *ops;
+ struct drm_gpuva_op *op;
+ struct drm_gpuva_op_remap *r;
+ struct drm_gpuva *va;
+ u64 req_end = req_addr + req_range;
+ int ret;
+
+ ops = kzalloc(sizeof(*ops), GFP_KERNEL);
+ if (!ops)
+ return ERR_PTR(-ENOMEM);
+
+ INIT_LIST_HEAD(&ops->list);
+
+ drm_gpuva_for_each_va_in_range(va, mgr, req_addr, req_end) {
+ struct drm_gem_object *obj = va->gem.obj;
+ u64 offset = va->gem.offset;
+ u64 addr = va->node.start;
+ u64 range = va->node.size;
+ u64 end = addr + range;
+
+ op = kzalloc(sizeof(*op), GFP_KERNEL);
+ if (!op) {
+ ret = -ENOMEM;
+ goto err_free_ops;
+ }
+
+ r = &op->remap;
+
+ if (addr < req_addr) {
+ r->prev = kzalloc(sizeof(*r->prev), GFP_KERNEL);
+ if (!r->prev) {
+ ret = -ENOMEM;
+ goto err_free_op;
+ }
+
+ r->prev->va.addr = addr;
+ r->prev->va.range = req_addr - addr;
+ r->prev->gem.obj = obj;
+ r->prev->gem.offset = offset;
+ }
+
+ if (end > req_end) {
+ r->next = kzalloc(sizeof(*r->next), GFP_KERNEL);
+ if (!r->next) {
+ ret = -ENOMEM;
+ goto err_free_prev;
+ }
+
+ r->next->va.addr = req_end;
+ r->next->va.range = end - req_end;
+ r->next->gem.obj = obj;
+ r->next->gem.offset = offset + (req_end - addr);
+ }
+
+ if (op->remap.prev || op->remap.next) {
+ op->op = DRM_GPUVA_OP_REMAP;
+ r->unmap = kzalloc(sizeof(*r->unmap), GFP_KERNEL);
+ if (!r->unmap) {
+ ret = -ENOMEM;
+ goto err_free_next;
+ }
+
+ r->unmap->va = va;
+ } else {
+ op->op = DRM_GPUVA_OP_UNMAP;
+ op->unmap.va = va;
+ }
+
+ list_add_tail(&op->entry, &ops->list);
+ }
+
+ return ops;
+
+err_free_next:
+ if (r->next)
+ kfree(r->next);
+err_free_prev:
+ if (r->prev)
+ kfree(r->prev);
+err_free_op:
+ kfree(op);
+err_free_ops:
+ drm_gpuva_ops_free(ops);
+ return ERR_PTR(ret);
+}
+EXPORT_SYMBOL(drm_gpuva_sm_unmap_ops_create);
+
+/**
+ * drm_gpuva_ops_free - free the given &drm_gpuva_ops
+ * @ops: the &drm_gpuva_ops to free
+ *
+ * Frees the given &drm_gpuva_ops structure including all the ops associated
+ * with it.
+ */
+void
+drm_gpuva_ops_free(struct drm_gpuva_ops *ops)
+{
+ struct drm_gpuva_op *op, *next;
+
+ drm_gpuva_for_each_op_safe(op, next, ops) {
+ list_del(&op->entry);
+ if (op->op == DRM_GPUVA_OP_REMAP) {
+ if (op->remap.prev)
+ kfree(op->remap.prev);
+
+ if (op->remap.next)
+ kfree(op->remap.next);
+
+ kfree(op->remap.unmap);
+ }
+ kfree(op);
+ }
+
+ kfree(ops);
+}
+EXPORT_SYMBOL(drm_gpuva_ops_free);
diff --git a/include/drm/drm_drv.h b/include/drm/drm_drv.h
index d7c521e8860f..6feacd93aca6 100644
--- a/include/drm/drm_drv.h
+++ b/include/drm/drm_drv.h
@@ -104,6 +104,12 @@ enum drm_driver_feature {
* acceleration should be handled by two drivers that are connected using auxiliary bus.
*/
DRIVER_COMPUTE_ACCEL = BIT(7),
+ /**
+ * @DRIVER_GEM_GPUVA:
+ *
+ * Driver supports user defined GPU VA bindings for GEM objects.
+ */
+ DRIVER_GEM_GPUVA = BIT(8),
/* IMPORTANT: Below are all the legacy flags, add new ones above. */
diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h
index 772a4adf5287..4a3679034966 100644
--- a/include/drm/drm_gem.h
+++ b/include/drm/drm_gem.h
@@ -36,6 +36,8 @@
#include <linux/kref.h>
#include <linux/dma-resv.h>
+#include <linux/list.h>
+#include <linux/mutex.h>
#include <drm/drm_vma_manager.h>
@@ -337,6 +339,17 @@ struct drm_gem_object {
*/
struct dma_resv _resv;
+ /**
+ * @gpuva:
+ *
+ * Provides the list and list mutex of GPU VAs attached to this
+ * GEM object.
+ */
+ struct {
+ struct list_head list;
+ struct mutex mutex;
+ } gpuva;
+
/**
* @funcs:
*
@@ -479,4 +492,66 @@ void drm_gem_lru_move_tail(struct drm_gem_lru *lru, struct drm_gem_object *obj);
unsigned long drm_gem_lru_scan(struct drm_gem_lru *lru, unsigned nr_to_scan,
bool (*shrink)(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 and the mutex
+ * protecting it.
+ *
+ * Calling this function is only necessary for drivers intending to support the
+ * &drm_driver_feature DRIVER_GEM_GPUVA.
+ */
+static inline void drm_gem_gpuva_init(struct drm_gem_object *obj)
+{
+ INIT_LIST_HEAD(&obj->gpuva.list);
+ mutex_init(&obj->gpuva.mutex);
+}
+
+/**
+ * drm_gem_gpuva_lock - lock the GEM's gpuva list mutex
+ * @obj: the &drm_gem_object
+ *
+ * This unlocks the mutex protecting the &drm_gem_object's &drm_gpuva list.
+ */
+static inline void drm_gem_gpuva_lock(struct drm_gem_object *obj)
+{
+ mutex_lock(&obj->gpuva.mutex);
+}
+
+/**
+ * drm_gem_gpuva_unlock - unlock the GEM's gpuva list mutex
+ * @obj: the &drm_gem_object
+ *
+ * This unlocks the mutex protecting the &drm_gem_object's &drm_gpuva list.
+ */
+static inline void drm_gem_gpuva_unlock(struct drm_gem_object *obj)
+{
+ mutex_unlock(&obj->gpuva.mutex);
+}
+
+/**
+ * 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
+ *
+ * This iterator walks over all &drm_gpuva structures associated with the
+ * &drm_gpuva_manager.
+ */
+#define drm_gem_for_each_gpuva(entry, obj) \
+ list_for_each_entry(entry, &obj->gpuva.list, head)
+
+/**
+ * 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
+ *
+ * This iterator walks over all &drm_gpuva 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, head)
+
#endif /* __DRM_GEM_H__ */
diff --git a/include/drm/drm_gpuva_mgr.h b/include/drm/drm_gpuva_mgr.h
new file mode 100644
index 000000000000..adeb0c916e91
--- /dev/null
+++ b/include/drm/drm_gpuva_mgr.h
@@ -0,0 +1,527 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#ifndef __DRM_GPUVA_MGR_H__
+#define __DRM_GPUVA_MGR_H__
+
+/*
+ * Copyright (c) 2022 Red Hat.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include <drm/drm_mm.h>
+#include <linux/mm.h>
+#include <linux/rbtree.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+
+struct drm_gpuva_region;
+struct drm_gpuva;
+struct drm_gpuva_ops;
+
+/**
+ * struct drm_gpuva_manager - DRM GPU VA Manager
+ *
+ * The DRM GPU VA Manager keeps track of a GPU's virtual address space by using
+ * the &drm_mm range allocator. Typically, this structure is embedded in bigger
+ * driver structures.
+ *
+ * Drivers can pass addresses and ranges in an arbitrary unit, e.g. bytes or
+ * pages.
+ *
+ * There should be one manager instance per GPU virtual address space.
+ */
+struct drm_gpuva_manager {
+ /**
+ * @name: the name of the DRM GPU VA space
+ */
+ const char *name;
+
+ /**
+ * @mm_start: start of the VA space
+ */
+ u64 mm_start;
+
+ /**
+ * @mm_range: length of the VA space
+ */
+ u64 mm_range;
+
+ /**
+ * @region_mm: the &drm_mm range allocator to track GPU VA regions
+ */
+ struct drm_mm region_mm;
+
+ /**
+ * @va_mm: the &drm_mm range allocator to track GPU VA mappings
+ */
+ struct drm_mm va_mm;
+
+ /**
+ * @kernel_alloc_node:
+ *
+ * &drm_mm_node representing the address space cutout reserved for
+ * the kernel
+ */
+ struct drm_mm_node kernel_alloc_node;
+};
+
+void drm_gpuva_manager_init(struct drm_gpuva_manager *mgr,
+ const char *name,
+ u64 start_offset, u64 range,
+ u64 reserve_offset, u64 reserve_range);
+void drm_gpuva_manager_destroy(struct drm_gpuva_manager *mgr);
+
+/**
+ * struct drm_gpuva_region - structure to track a portion of GPU VA space
+ *
+ * This structure represents a portion of a GPUs VA space and is associated
+ * with a &drm_gpuva_manager. Internally it is based on a &drm_mm_node.
+ *
+ * GPU VA mappings, represented by &drm_gpuva objects, are restricted to be
+ * placed within a &drm_gpuva_region.
+ */
+struct drm_gpuva_region {
+ /**
+ * @node: the &drm_mm_node to track the GPU VA region
+ */
+ struct drm_mm_node node;
+
+ /**
+ * @mgr: the &drm_gpuva_manager this object is associated with
+ */
+ struct drm_gpuva_manager *mgr;
+
+ /**
+ * @sparse: indicates whether this region is sparse
+ */
+ bool sparse;
+};
+
+struct drm_gpuva_region *
+drm_gpuva_region_find(struct drm_gpuva_manager *mgr,
+ u64 addr, u64 range);
+int drm_gpuva_region_insert(struct drm_gpuva_manager *mgr,
+ struct drm_gpuva_region *reg,
+ u64 addr, u64 range);
+void drm_gpuva_region_destroy(struct drm_gpuva_manager *mgr,
+ struct drm_gpuva_region *reg);
+
+int drm_gpuva_insert(struct drm_gpuva_manager *mgr,
+ struct drm_gpuva *va,
+ u64 addr, u64 range);
+/**
+ * drm_gpuva_for_each_region_in_range - iternator to walk over a range of nodes
+ * @node__: &drm_gpuva_region structure to assign to in each iteration step
+ * @gpuva__: &drm_gpuva_manager structure to walk
+ * @start__: starting offset, the first node will overlap this
+ * @end__: ending offset, the last node will start before this (but may overlap)
+ *
+ * This iterator walks over all nodes in the range allocator that lie
+ * between @start and @end. It is implemented similarly to list_for_each(),
+ * but is using &drm_mm's internal interval tree to accelerate the search for
+ * the starting node, and hence isn't safe against removal of elements. It
+ * assumes that @end is within (or is the upper limit of) the &drm_gpuva_manager.
+ * If [@start, @end] are beyond the range of the &drm_gpuva_manager, the
+ * iterator may walk over the special _unallocated_ &drm_mm.head_node of the
+ * backing &drm_mm, and may even continue indefinitely.
+ */
+#define drm_gpuva_for_each_region_in_range(node__, gpuva__, start__, end__) \
+ for (node__ = (struct drm_gpuva_region *)__drm_mm_interval_first(&(gpuva__)->region_mm, \
+ (start__), (end__)-1); \
+ node__->node.start < (end__); \
+ node__ = (struct drm_gpuva_region *)list_next_entry(&node__->node, node_list))
+
+/**
+ * drm_gpuva_for_each_region - iternator to walk over a range of nodes
+ * @entry: &drm_gpuva_region structure to assign to in each iteration step
+ * @gpuva: &drm_gpuva_manager structure to walk
+ *
+ * This iterator walks over all &drm_gpuva_region structures associated with the
+ * &drm_gpuva_manager.
+ */
+#define drm_gpuva_for_each_region(entry, gpuva) \
+ list_for_each_entry(entry, drm_mm_nodes(&(gpuva)->region_mm), node.node_list)
+
+/**
+ * drm_gpuva_for_each_region_safe - iternator to safely walk over a range of
+ * nodes
+ * @entry: &drm_gpuva_region structure to assign to in each iteration step
+ * @next: &next &drm_gpuva_region to store the next step
+ * @gpuva: &drm_gpuva_manager structure to walk
+ *
+ * This iterator walks over all &drm_gpuva_region structures associated with the
+ * &drm_gpuva_manager. It is implemented with list_for_each_safe(), so save
+ * against removal of elements.
+ */
+#define drm_gpuva_for_each_region_safe(entry, next, gpuva) \
+ list_for_each_entry_safe(entry, next, drm_mm_nodes(&(gpuva)->region_mm), node.node_list)
+
+
+/**
+ * enum drm_gpuva_flags - flags for struct drm_gpuva
+ */
+enum drm_gpuva_flags {
+ /**
+ * @DRM_GPUVA_SWAPPED: flag indicating that the &drm_gpuva is swapped
+ */
+ DRM_GPUVA_SWAPPED = (1 << 0),
+};
+
+/**
+ * struct drm_gpuva - structure to track a GPU VA mapping
+ *
+ * This structure represents a GPU VA mapping and is associated with a
+ * &drm_gpuva_manager. Internally it is based on a &drm_mm_node.
+ *
+ * Typically, this structure is embedded in bigger driver structures.
+ */
+struct drm_gpuva {
+ /**
+ * @node: the &drm_mm_node to track the GPU VA mapping
+ */
+ struct drm_mm_node node;
+
+ /**
+ * @mgr: the &drm_gpuva_manager this object is associated with
+ */
+ struct drm_gpuva_manager *mgr;
+
+ /**
+ * @region: the &drm_gpuva_region the &drm_gpuva is mapped in
+ */
+ struct drm_gpuva_region *region;
+
+ /**
+ * @head: the &list_head to attach this object to a &drm_gem_object
+ */
+ struct list_head head;
+
+ /**
+ * @flags: the &drm_gpuva_flags for this mapping
+ */
+ enum drm_gpuva_flags flags;
+
+ /**
+ * @gem: structure containing the &drm_gem_object and it's offset
+ */
+ struct {
+ /**
+ * @offset: the offset within the &drm_gem_object
+ */
+ u64 offset;
+
+ /**
+ * @obj: the mapped &drm_gem_object
+ */
+ struct drm_gem_object *obj;
+ } gem;
+};
+
+void drm_gpuva_link_locked(struct drm_gpuva *va);
+void drm_gpuva_link_unlocked(struct drm_gpuva *va);
+void drm_gpuva_unlink_locked(struct drm_gpuva *va);
+void drm_gpuva_unlink_unlocked(struct drm_gpuva *va);
+
+void drm_gpuva_destroy_locked(struct drm_gpuva *va);
+void drm_gpuva_destroy_unlocked(struct drm_gpuva *va);
+
+struct drm_gpuva *drm_gpuva_find(struct drm_gpuva_manager *mgr,
+ u64 addr, u64 range);
+struct drm_gpuva *drm_gpuva_find_prev(struct drm_gpuva_manager *mgr, u64 start);
+struct drm_gpuva *drm_gpuva_find_next(struct drm_gpuva_manager *mgr, u64 end);
+
+/**
+ * drm_gpuva_swap - sets whether the backing BO of this &drm_gpuva is swapped
+ * @va: the &drm_gpuva to set the swap flag of
+ * @swap: indicates whether the &drm_gpuva is swapped
+ */
+static inline void drm_gpuva_swap(struct drm_gpuva *va, bool swap)
+{
+ if (swap)
+ va->flags |= DRM_GPUVA_SWAPPED;
+ else
+ va->flags &= ~DRM_GPUVA_SWAPPED;
+}
+
+/**
+ * drm_gpuva_swapped - indicates whether the backing BO of this &drm_gpuva
+ * is swapped
+ * @va: the &drm_gpuva to check
+ */
+static inline bool drm_gpuva_swapped(struct drm_gpuva *va)
+{
+ return va->flags & DRM_GPUVA_SWAPPED;
+}
+
+/**
+ * drm_gpuva_for_each_va_in_range - iternator to walk over a range of nodes
+ * @node__: &drm_gpuva structure to assign to in each iteration step
+ * @gpuva__: &drm_gpuva_manager structure to walk
+ * @start__: starting offset, the first node will overlap this
+ * @end__: ending offset, the last node will start before this (but may overlap)
+ *
+ * This iterator walks over all nodes in the range allocator that lie
+ * between @start and @end. It is implemented similarly to list_for_each(),
+ * but is using &drm_mm's internal interval tree to accelerate the search for
+ * the starting node, and hence isn't safe against removal of elements. It
+ * assumes that @end is within (or is the upper limit of) the &drm_gpuva_manager.
+ * If [@start, @end] are beyond the range of the &drm_gpuva_manager, the
+ * iterator may walk over the special _unallocated_ &drm_mm.head_node of the
+ * backing &drm_mm, and may even continue indefinitely.
+ */
+#define drm_gpuva_for_each_va_in_range(node__, gpuva__, start__, end__) \
+ for (node__ = (struct drm_gpuva *)__drm_mm_interval_first(&(gpuva__)->va_mm, \
+ (start__), (end__)-1); \
+ node__->node.start < (end__); \
+ node__ = (struct drm_gpuva *)list_next_entry(&node__->node, node_list))
+
+/**
+ * drm_gpuva_for_each_va - iternator to walk over a range of nodes
+ * @entry: &drm_gpuva structure to assign to in each iteration step
+ * @gpuva: &drm_gpuva_manager structure to walk
+ *
+ * This iterator walks over all &drm_gpuva structures associated with the
+ * &drm_gpuva_manager.
+ */
+#define drm_gpuva_for_each_va(entry, gpuva) \
+ list_for_each_entry(entry, drm_mm_nodes(&(gpuva)->va_mm), node.node_list)
+
+/**
+ * drm_gpuva_for_each_va_safe - iternator to safely walk over a range of
+ * nodes
+ * @entry: &drm_gpuva structure to assign to in each iteration step
+ * @next: &next &drm_gpuva to store the next step
+ * @gpuva: &drm_gpuva_manager structure to walk
+ *
+ * This iterator walks over all &drm_gpuva structures associated with the
+ * &drm_gpuva_manager. It is implemented with list_for_each_safe(), so save
+ * against removal of elements.
+ */
+#define drm_gpuva_for_each_va_safe(entry, next, gpuva) \
+ list_for_each_entry_safe(entry, next, drm_mm_nodes(&(gpuva)->va_mm), node.node_list)
+
+/**
+ * enum drm_gpuva_op_type - GPU VA operation type
+ *
+ * Operations to alter the GPU VA mappings tracked by the &drm_gpuva_manager
+ * can be map, remap or unmap operations.
+ */
+enum drm_gpuva_op_type {
+ /**
+ * @DRM_GPUVA_OP_MAP: the map op type
+ */
+ DRM_GPUVA_OP_MAP,
+
+ /**
+ * @DRM_GPUVA_OP_REMAP: the remap op type
+ */
+ DRM_GPUVA_OP_REMAP,
+
+ /**
+ * @DRM_GPUVA_OP_UNMAP: the unmap op type
+ */
+ DRM_GPUVA_OP_UNMAP,
+};
+
+/**
+ * struct drm_gpuva_op_map - GPU VA map operation
+ *
+ * This structure represents a single map operation generated by the
+ * DRM GPU VA manager.
+ */
+struct drm_gpuva_op_map {
+ /**
+ * @va: structure containing address and range of a map
+ * operation
+ */
+ struct {
+ /**
+ * @addr: the base address of the new mapping
+ */
+ u64 addr;
+
+ /**
+ * @range: the range of the new mapping
+ */
+ u64 range;
+ } va;
+
+ /**
+ * @gem: structure containing the &drm_gem_object and it's offset
+ */
+ struct {
+ /**
+ * @offset: the offset within the &drm_gem_object
+ */
+ u64 offset;
+
+ /**
+ * @obj: the &drm_gem_object to map
+ */
+ struct drm_gem_object *obj;
+ } gem;
+};
+
+/**
+ * struct drm_gpuva_op_unmap - GPU VA unmap operation
+ *
+ * This structure represents a single unmap operation generated by the
+ * DRM GPU VA manager.
+ */
+struct drm_gpuva_op_unmap {
+ /**
+ * @va: the &drm_gpuva to unmap
+ */
+ struct drm_gpuva *va;
+
+ /**
+ * @keep:
+ *
+ * Indicates whether this &drm_gpuva is physically contiguous with the
+ * original mapping request.
+ *
+ * Optionally, if &keep is set, drivers may keep the actual page table
+ * mappings for this &drm_gpuva, adding the missing page table entries
+ * only and update the &drm_gpuva_manager accordingly.
+ */
+ bool keep;
+};
+
+/**
+ * struct drm_gpuva_op_remap - GPU VA remap operation
+ *
+ * This represents a single remap operation generated by the DRM GPU VA manager.
+ *
+ * A remap operation is generated when an existing GPU VA mmapping is split up
+ * by inserting a new GPU VA mapping or by partially unmapping existent
+ * mapping(s), hence it consists of a maximum of two map and one unmap
+ * operation.
+ *
+ * The @unmap operation takes care of removing the original existing mapping.
+ * @prev is used to remap the preceding part, @next the subsequent part.
+ *
+ * If either a new mapping's start address is aligned with the start address
+ * of the old mapping or the new mapping's end address is aligned with the
+ * end address of the old mapping, either @prev or @next is NULL.
+ *
+ * Note, the reason for a dedicated remap operation, rather than arbitrary
+ * unmap and map operations, is to give drivers the chance of extracting driver
+ * specific data for creating the new mappings from the unmap operations's
+ * &drm_gpuva structure which typically is embedded in larger driver specific
+ * structures.
+ */
+struct drm_gpuva_op_remap {
+ /**
+ * @prev: the preceding part of a split mapping
+ */
+ struct drm_gpuva_op_map *prev;
+
+ /**
+ * @next: the subsequent part of a split mapping
+ */
+ struct drm_gpuva_op_map *next;
+
+ /**
+ * @unmap: the unmap operation for the original existing mapping
+ */
+ struct drm_gpuva_op_unmap *unmap;
+};
+
+/**
+ * struct drm_gpuva_op - GPU VA operation
+ *
+ * This structure represents a single generic operation, which can be either
+ * map, unmap or remap.
+ *
+ * The particular type of the operation is defined by @op.
+ */
+struct drm_gpuva_op {
+ /**
+ * @entry:
+ *
+ * The &list_head used to distribute instances of this struct within
+ * &drm_gpuva_ops.
+ */
+ struct list_head entry;
+
+ /**
+ * @op: the type of the operation
+ */
+ enum drm_gpuva_op_type op;
+
+ union {
+ /**
+ * @map: the map operation
+ */
+ struct drm_gpuva_op_map map;
+
+ /**
+ * @unmap: the unmap operation
+ */
+ struct drm_gpuva_op_unmap unmap;
+
+ /**
+ * @remap: the remap operation
+ */
+ struct drm_gpuva_op_remap remap;
+ };
+};
+
+/**
+ * struct drm_gpuva_ops - wraps a list of &drm_gpuva_op
+ */
+struct drm_gpuva_ops {
+ /**
+ * @list: the &list_head
+ */
+ struct list_head list;
+};
+
+/**
+ * drm_gpuva_for_each_op - iterator to walk over all ops
+ * @op: &drm_gpuva_op to assign in each iteration step
+ * @ops: &drm_gpuva_ops to walk
+ *
+ * This iterator walks over all ops within a given list of operations.
+ */
+#define drm_gpuva_for_each_op(op, ops) list_for_each_entry(op, &(ops)->list, entry)
+
+/**
+ * drm_gpuva_for_each_op_safe - iterator to safely walk over all ops
+ * @op: &drm_gpuva_op to assign in each iteration step
+ * @next: &next &drm_gpuva_op to store the next step
+ * @ops: &drm_gpuva_ops to walk
+ *
+ * This iterator walks over all ops within a given list of operations. It is
+ * implemented with list_for_each_safe(), so save against removal of elements.
+ */
+#define drm_gpuva_for_each_op_safe(op, next, ops) \
+ list_for_each_entry_safe(op, next, &(ops)->list, entry)
+
+struct drm_gpuva_ops *
+drm_gpuva_sm_map_ops_create(struct drm_gpuva_manager *mgr,
+ u64 addr, u64 range,
+ struct drm_gem_object *obj, u64 offset);
+struct drm_gpuva_ops *
+drm_gpuva_sm_unmap_ops_create(struct drm_gpuva_manager *mgr,
+ u64 addr, u64 range);
+void drm_gpuva_ops_free(struct drm_gpuva_ops *ops);
+
+#endif /* __DRM_GPUVA_MGR_H__ */
--
2.39.0
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