[Intel-xe] [PATCH 3/3] drm/xe: NULL binding implementation
Matthew Brost
matthew.brost at intel.com
Thu Jun 8 05:03:33 UTC 2023
Add uAPI and implementation for NULL bindings. A NULL binding is defined
as writes dropped and read zero. A single bit in the uAPI has been added
which results in a single bit in the PTEs being set.
NULL bindings are indended to be used to implement VK sparse bindings,
in particular residencyNonResidentStrict property.
Suggested-by: Paulo Zanoni <paulo.r.zanoni at intel.com>
Signed-off-by: Matthew Brost <matthew.brost at intel.com>
---
drivers/gpu/drm/xe/xe_bo.h | 1 +
drivers/gpu/drm/xe/xe_exec.c | 2 +
drivers/gpu/drm/xe/xe_gt_pagefault.c | 4 +-
drivers/gpu/drm/xe/xe_pt.c | 71 +++++++++++++++------
drivers/gpu/drm/xe/xe_vm.c | 95 ++++++++++++++++++----------
drivers/gpu/drm/xe/xe_vm.h | 12 +++-
drivers/gpu/drm/xe/xe_vm_types.h | 1 +
include/uapi/drm/xe_drm.h | 8 +++
8 files changed, 138 insertions(+), 56 deletions(-)
diff --git a/drivers/gpu/drm/xe/xe_bo.h b/drivers/gpu/drm/xe/xe_bo.h
index dd3d448fee0b..3a148cc6e811 100644
--- a/drivers/gpu/drm/xe/xe_bo.h
+++ b/drivers/gpu/drm/xe/xe_bo.h
@@ -61,6 +61,7 @@
#define XE_PPGTT_PTE_LM BIT_ULL(11)
#define XE_PDE_64K BIT_ULL(6)
#define XE_PTE_PS64 BIT_ULL(8)
+#define XE_PTE_NULL BIT_ULL(9)
#define XE_PAGE_PRESENT BIT_ULL(0)
#define XE_PAGE_RW BIT_ULL(1)
diff --git a/drivers/gpu/drm/xe/xe_exec.c b/drivers/gpu/drm/xe/xe_exec.c
index e44076ee2e11..4f7694a29348 100644
--- a/drivers/gpu/drm/xe/xe_exec.c
+++ b/drivers/gpu/drm/xe/xe_exec.c
@@ -120,6 +120,8 @@ static int xe_exec_begin(struct xe_engine *e, struct ww_acquire_ctx *ww,
* to a location where the GPU can access it).
*/
list_for_each_entry(vma, &vm->rebind_list, rebind_link) {
+ XE_WARN_ON(xe_vma_is_null(vma));
+
if (xe_vma_is_userptr(vma))
continue;
diff --git a/drivers/gpu/drm/xe/xe_gt_pagefault.c b/drivers/gpu/drm/xe/xe_gt_pagefault.c
index 73db7f7c0381..6faebd02f3fb 100644
--- a/drivers/gpu/drm/xe/xe_gt_pagefault.c
+++ b/drivers/gpu/drm/xe/xe_gt_pagefault.c
@@ -533,8 +533,8 @@ static int handle_acc(struct xe_gt *gt, struct acc *acc)
trace_xe_vma_acc(vma);
- /* Userptr can't be migrated, nothing to do */
- if (xe_vma_is_userptr(vma))
+ /* Userptr or null can't be migrated, nothing to do */
+ if (xe_vma_has_no_bo(vma))
goto unlock_vm;
/* Lock VM and BOs dma-resv */
diff --git a/drivers/gpu/drm/xe/xe_pt.c b/drivers/gpu/drm/xe/xe_pt.c
index 39ec94549439..265ee45bee5c 100644
--- a/drivers/gpu/drm/xe/xe_pt.c
+++ b/drivers/gpu/drm/xe/xe_pt.c
@@ -81,7 +81,9 @@ u64 gen8_pde_encode(struct xe_bo *bo, u64 bo_offset,
static dma_addr_t vma_addr(struct xe_vma *vma, u64 offset,
size_t page_size, bool *is_vram)
{
- if (xe_vma_is_userptr(vma)) {
+ if (xe_vma_is_null(vma)) {
+ return 0;
+ } else if (xe_vma_is_userptr(vma)) {
struct xe_res_cursor cur;
u64 page;
@@ -559,6 +561,10 @@ static bool xe_pt_hugepte_possible(u64 addr, u64 next, unsigned int level,
if (next - xe_walk->va_curs_start > xe_walk->curs->size)
return false;
+ /* null VMA's do not have dma adresses */
+ if (xe_walk->pte_flags & XE_PTE_FLAG_NULL)
+ return true;
+
/* Is the DMA address huge PTE size aligned? */
size = next - addr;
dma = addr - xe_walk->va_curs_start + xe_res_dma(xe_walk->curs);
@@ -575,6 +581,10 @@ xe_pt_scan_64K(u64 addr, u64 next, struct xe_pt_stage_bind_walk *xe_walk)
{
struct xe_res_cursor curs = *xe_walk->curs;
+ /* null VMA's do not have dma adresses */
+ if (xe_walk->pte_flags & XE_PTE_FLAG_NULL)
+ return true;
+
if (!IS_ALIGNED(addr, SZ_64K))
return false;
@@ -631,12 +641,29 @@ xe_pt_stage_bind_entry(struct xe_ptw *parent, pgoff_t offset,
/* Is this a leaf entry ?*/
if (level == 0 || xe_pt_hugepte_possible(addr, next, level, xe_walk)) {
struct xe_res_cursor *curs = xe_walk->curs;
+ u64 pte = 0;
+ bool is_null = xe_walk->pte_flags & XE_PTE_FLAG_NULL;
XE_WARN_ON(xe_walk->va_curs_start != addr);
- pte = __gen8_pte_encode(xe_res_dma(curs) + xe_walk->dma_offset,
- xe_walk->cache, xe_walk->pte_flags,
- level);
+ if (is_null) {
+ pte |= XE_PAGE_PRESENT | XE_PAGE_RW;
+ if (xe_walk->pte_flags & XE_PTE_FLAG_READ_ONLY)
+ pte &= ~XE_PAGE_RW;
+
+ if (level == 1)
+ pte |= XE_PDE_PS_2M;
+ else if (level == 2)
+ pte |= XE_PDPE_PS_1G;
+
+ pte |= XE_PTE_NULL;
+ } else {
+ pte = __gen8_pte_encode(xe_res_dma(curs) +
+ xe_walk->dma_offset,
+ xe_walk->cache,
+ xe_walk->pte_flags,
+ level);
+ }
pte |= xe_walk->default_pte;
/*
@@ -654,7 +681,8 @@ xe_pt_stage_bind_entry(struct xe_ptw *parent, pgoff_t offset,
if (unlikely(ret))
return ret;
- xe_res_next(curs, next - addr);
+ if (!is_null)
+ xe_res_next(curs, next - addr);
xe_walk->va_curs_start = next;
*action = ACTION_CONTINUE;
@@ -761,24 +789,29 @@ xe_pt_stage_bind(struct xe_tile *tile, struct xe_vma *vma,
xe_walk.dma_offset = vram_region_gpu_offset(bo->ttm.resource);
xe_walk.cache = XE_CACHE_WB;
} else {
- if (!xe_vma_is_userptr(vma) && bo->flags & XE_BO_SCANOUT_BIT)
+ if (!xe_vma_has_no_bo(vma) && bo->flags & XE_BO_SCANOUT_BIT)
xe_walk.cache = XE_CACHE_WT;
else
xe_walk.cache = XE_CACHE_WB;
}
- if (!xe_vma_is_userptr(vma) && xe_bo_is_stolen(bo))
+ if (!xe_vma_has_no_bo(vma) && xe_bo_is_stolen(bo))
xe_walk.dma_offset = xe_ttm_stolen_gpu_offset(xe_bo_device(bo));
xe_bo_assert_held(bo);
- if (xe_vma_is_userptr(vma))
- xe_res_first_sg(vma->userptr.sg, 0, vma->end - vma->start + 1,
- &curs);
- else if (xe_bo_is_vram(bo) || xe_bo_is_stolen(bo))
- xe_res_first(bo->ttm.resource, vma->bo_offset,
- vma->end - vma->start + 1, &curs);
- else
- xe_res_first_sg(xe_bo_get_sg(bo), vma->bo_offset,
- vma->end - vma->start + 1, &curs);
+
+ if (!xe_vma_is_null(vma)) {
+ if (xe_vma_is_userptr(vma))
+ xe_res_first_sg(vma->userptr.sg, 0,
+ vma->end - vma->start + 1, &curs);
+ else if (xe_bo_is_vram(bo) || xe_bo_is_stolen(bo))
+ xe_res_first(bo->ttm.resource, vma->bo_offset,
+ vma->end - vma->start + 1, &curs);
+ else
+ xe_res_first_sg(xe_bo_get_sg(bo), vma->bo_offset,
+ vma->end - vma->start + 1, &curs);
+ } else {
+ curs.size = vma->end - vma->start + 1;
+ }
ret = xe_pt_walk_range(&pt->base, pt->level, vma->start, vma->end + 1,
&xe_walk.base);
@@ -967,7 +1000,7 @@ static void xe_pt_commit_locks_assert(struct xe_vma *vma)
if (xe_vma_is_userptr(vma))
lockdep_assert_held_read(&vm->userptr.notifier_lock);
- else
+ else if (!xe_vma_is_null(vma))
dma_resv_assert_held(vma->bo->ttm.base.resv);
dma_resv_assert_held(&vm->resv);
@@ -1330,7 +1363,7 @@ __xe_pt_bind_vma(struct xe_tile *tile, struct xe_vma *vma, struct xe_engine *e,
DMA_RESV_USAGE_KERNEL :
DMA_RESV_USAGE_BOOKKEEP);
- if (!xe_vma_is_userptr(vma) && !vma->bo->vm)
+ if (!xe_vma_has_no_bo(vma) && !vma->bo->vm)
dma_resv_add_fence(vma->bo->ttm.base.resv, fence,
DMA_RESV_USAGE_BOOKKEEP);
xe_pt_commit_bind(vma, entries, num_entries, rebind,
@@ -1647,7 +1680,7 @@ __xe_pt_unbind_vma(struct xe_tile *tile, struct xe_vma *vma, struct xe_engine *e
DMA_RESV_USAGE_BOOKKEEP);
/* This fence will be installed by caller when doing eviction */
- if (!xe_vma_is_userptr(vma) && !vma->bo->vm)
+ if (!xe_vma_has_no_bo(vma) && !vma->bo->vm)
dma_resv_add_fence(vma->bo->ttm.base.resv, fence,
DMA_RESV_USAGE_BOOKKEEP);
xe_pt_commit_unbind(vma, entries, num_entries,
diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c
index 94fc9c330235..f7629db275f9 100644
--- a/drivers/gpu/drm/xe/xe_vm.c
+++ b/drivers/gpu/drm/xe/xe_vm.c
@@ -590,7 +590,7 @@ static void preempt_rebind_work_func(struct work_struct *w)
goto out_unlock;
list_for_each_entry(vma, &vm->rebind_list, rebind_link) {
- if (xe_vma_is_userptr(vma) || vma->destroyed)
+ if (xe_vma_has_no_bo(vma) || vma->destroyed)
continue;
err = xe_bo_validate(vma->bo, vm, false);
@@ -843,6 +843,7 @@ static struct xe_vma *xe_vma_create(struct xe_vm *vm,
u64 bo_offset_or_userptr,
u64 start, u64 end,
bool read_only,
+ bool is_null,
u64 tile_mask)
{
struct xe_vma *vma;
@@ -868,8 +869,11 @@ static struct xe_vma *xe_vma_create(struct xe_vm *vm,
vma->vm = vm;
vma->start = start;
vma->end = end;
+ vma->pte_flags = 0;
if (read_only)
- vma->pte_flags = XE_PTE_FLAG_READ_ONLY;
+ vma->pte_flags |= XE_PTE_FLAG_READ_ONLY;
+ if (is_null)
+ vma->pte_flags |= XE_PTE_FLAG_NULL;
if (tile_mask) {
vma->tile_mask = tile_mask;
@@ -886,23 +890,26 @@ static struct xe_vma *xe_vma_create(struct xe_vm *vm,
vma->bo_offset = bo_offset_or_userptr;
vma->bo = xe_bo_get(bo);
list_add_tail(&vma->bo_link, &bo->vmas);
- } else /* userptr */ {
- u64 size = end - start + 1;
- int err;
+ } else /* userptr or null */ {
+ if (!is_null) {
+ u64 size = end - start + 1;
+ int err;
- vma->userptr.ptr = bo_offset_or_userptr;
+ vma->userptr.ptr = bo_offset_or_userptr;
- err = mmu_interval_notifier_insert(&vma->userptr.notifier,
- current->mm,
- vma->userptr.ptr, size,
- &vma_userptr_notifier_ops);
- if (err) {
- kfree(vma);
- vma = ERR_PTR(err);
- return vma;
+ err = mmu_interval_notifier_insert(&vma->userptr.notifier,
+ current->mm,
+ vma->userptr.ptr, size,
+ &vma_userptr_notifier_ops);
+ if (err) {
+ kfree(vma);
+ vma = ERR_PTR(err);
+ return vma;
+ }
+
+ vma->userptr.notifier_seq = LONG_MAX;
}
- vma->userptr.notifier_seq = LONG_MAX;
xe_vm_get(vm);
}
@@ -942,6 +949,8 @@ static void xe_vma_destroy_late(struct xe_vma *vma)
*/
mmu_interval_notifier_remove(&vma->userptr.notifier);
xe_vm_put(vm);
+ } else if (xe_vma_is_null(vma)) {
+ xe_vm_put(vm);
} else {
xe_bo_put(vma->bo);
}
@@ -1024,7 +1033,7 @@ static void xe_vma_destroy(struct xe_vma *vma, struct dma_fence *fence)
list_del_init(&vma->userptr.invalidate_link);
spin_unlock(&vm->userptr.invalidated_lock);
list_del(&vma->userptr_link);
- } else {
+ } else if (!xe_vma_is_null(vma)) {
xe_bo_assert_held(vma->bo);
list_del(&vma->bo_link);
@@ -1391,7 +1400,7 @@ void xe_vm_close_and_put(struct xe_vm *vm)
while (vm->vmas.rb_node) {
struct xe_vma *vma = to_xe_vma(vm->vmas.rb_node);
- if (xe_vma_is_userptr(vma)) {
+ if (xe_vma_has_no_bo(vma)) {
down_read(&vm->userptr.notifier_lock);
vma->destroyed = true;
up_read(&vm->userptr.notifier_lock);
@@ -1400,7 +1409,7 @@ void xe_vm_close_and_put(struct xe_vm *vm)
rb_erase(&vma->vm_node, &vm->vmas);
/* easy case, remove from VMA? */
- if (xe_vma_is_userptr(vma) || vma->bo->vm) {
+ if (xe_vma_has_no_bo(vma) || vma->bo->vm) {
xe_vma_destroy(vma, NULL);
continue;
}
@@ -2034,7 +2043,7 @@ static int xe_vm_prefetch(struct xe_vm *vm, struct xe_vma *vma,
XE_BUG_ON(region > ARRAY_SIZE(region_to_mem_type));
- if (!xe_vma_is_userptr(vma)) {
+ if (!xe_vma_has_no_bo(vma)) {
err = xe_bo_migrate(vma->bo, region_to_mem_type[region]);
if (err)
return err;
@@ -2643,6 +2652,8 @@ static struct xe_vma *vm_unbind_lookup_vmas(struct xe_vm *vm,
lookup->start - 1,
(first->pte_flags &
XE_PTE_FLAG_READ_ONLY),
+ (first->pte_flags &
+ XE_PTE_FLAG_NULL),
first->tile_mask);
if (first->bo)
xe_bo_unlock(first->bo, &ww);
@@ -2675,6 +2686,7 @@ static struct xe_vma *vm_unbind_lookup_vmas(struct xe_vm *vm,
last->end,
(last->pte_flags &
XE_PTE_FLAG_READ_ONLY),
+ (last->pte_flags & XE_PTE_FLAG_NULL),
last->tile_mask);
if (last->bo)
xe_bo_unlock(last->bo, &ww);
@@ -2742,7 +2754,7 @@ static struct xe_vma *vm_prefetch_lookup_vmas(struct xe_vm *vm,
*next;
struct rb_node *node;
- if (!xe_vma_is_userptr(vma)) {
+ if (!xe_vma_has_no_bo(vma)) {
if (!xe_bo_can_migrate(vma->bo, region_to_mem_type[region]))
return ERR_PTR(-EINVAL);
}
@@ -2751,7 +2763,7 @@ static struct xe_vma *vm_prefetch_lookup_vmas(struct xe_vm *vm,
while ((node = rb_next(node))) {
if (!xe_vma_cmp_vma_cb(lookup, node)) {
__vma = to_xe_vma(node);
- if (!xe_vma_is_userptr(__vma)) {
+ if (!xe_vma_has_no_bo(__vma)) {
if (!xe_bo_can_migrate(__vma->bo, region_to_mem_type[region]))
goto flush_list;
}
@@ -2765,7 +2777,7 @@ static struct xe_vma *vm_prefetch_lookup_vmas(struct xe_vm *vm,
while ((node = rb_prev(node))) {
if (!xe_vma_cmp_vma_cb(lookup, node)) {
__vma = to_xe_vma(node);
- if (!xe_vma_is_userptr(__vma)) {
+ if (!xe_vma_has_no_bo(__vma)) {
if (!xe_bo_can_migrate(__vma->bo, region_to_mem_type[region]))
goto flush_list;
}
@@ -2824,21 +2836,23 @@ static struct xe_vma *vm_bind_ioctl_lookup_vma(struct xe_vm *vm,
switch (VM_BIND_OP(op)) {
case XE_VM_BIND_OP_MAP:
- XE_BUG_ON(!bo);
-
- err = xe_bo_lock(bo, &ww, 0, true);
- if (err)
- return ERR_PTR(err);
+ if (bo) {
+ err = xe_bo_lock(bo, &ww, 0, true);
+ if (err)
+ return ERR_PTR(err);
+ }
vma = xe_vma_create(vm, bo, bo_offset_or_userptr, addr,
addr + range - 1,
op & XE_VM_BIND_FLAG_READONLY,
+ op & XE_VM_BIND_FLAG_NULL,
tile_mask);
- xe_bo_unlock(bo, &ww);
+ if (bo)
+ xe_bo_unlock(bo, &ww);
if (!vma)
return ERR_PTR(-ENOMEM);
xe_vm_insert_vma(vm, vma);
- if (!bo->vm) {
+ if (bo && !bo->vm) {
vm_insert_extobj(vm, vma);
err = add_preempt_fences(vm, bo);
if (err) {
@@ -2872,6 +2886,7 @@ static struct xe_vma *vm_bind_ioctl_lookup_vma(struct xe_vm *vm,
vma = xe_vma_create(vm, NULL, bo_offset_or_userptr, addr,
addr + range - 1,
op & XE_VM_BIND_FLAG_READONLY,
+ op & XE_VM_BIND_FLAG_NULL,
tile_mask);
if (!vma)
return ERR_PTR(-ENOMEM);
@@ -2897,11 +2912,12 @@ static struct xe_vma *vm_bind_ioctl_lookup_vma(struct xe_vm *vm,
#ifdef TEST_VM_ASYNC_OPS_ERROR
#define SUPPORTED_FLAGS \
(FORCE_ASYNC_OP_ERROR | XE_VM_BIND_FLAG_ASYNC | \
- XE_VM_BIND_FLAG_READONLY | XE_VM_BIND_FLAG_IMMEDIATE | 0xffff)
+ XE_VM_BIND_FLAG_READONLY | XE_VM_BIND_FLAG_IMMEDIATE | \
+ XE_VM_BIND_FLAG_NULL | 0xffff)
#else
#define SUPPORTED_FLAGS \
(XE_VM_BIND_FLAG_ASYNC | XE_VM_BIND_FLAG_READONLY | \
- XE_VM_BIND_FLAG_IMMEDIATE | 0xffff)
+ XE_VM_BIND_FLAG_IMMEDIATE | XE_VM_BIND_FLAG_NULL | 0xffff)
#endif
#define XE_64K_PAGE_MASK 0xffffull
@@ -2949,6 +2965,7 @@ static int vm_bind_ioctl_check_args(struct xe_device *xe,
u32 obj = (*bind_ops)[i].obj;
u64 obj_offset = (*bind_ops)[i].obj_offset;
u32 region = (*bind_ops)[i].region;
+ bool is_null = op & XE_VM_BIND_FLAG_NULL;
if (XE_IOCTL_ERR(xe, (*bind_ops)[i].pad) ||
XE_IOCTL_ERR(xe, (*bind_ops)[i].reserved[0] ||
@@ -2982,8 +2999,13 @@ static int vm_bind_ioctl_check_args(struct xe_device *xe,
if (XE_IOCTL_ERR(xe, VM_BIND_OP(op) >
XE_VM_BIND_OP_PREFETCH) ||
XE_IOCTL_ERR(xe, op & ~SUPPORTED_FLAGS) ||
+ XE_IOCTL_ERR(xe, obj && is_null) ||
+ XE_IOCTL_ERR(xe, obj_offset && is_null) ||
+ XE_IOCTL_ERR(xe, VM_BIND_OP(op) != XE_VM_BIND_OP_MAP &&
+ is_null) ||
XE_IOCTL_ERR(xe, !obj &&
- VM_BIND_OP(op) == XE_VM_BIND_OP_MAP) ||
+ VM_BIND_OP(op) == XE_VM_BIND_OP_MAP &&
+ !is_null) ||
XE_IOCTL_ERR(xe, !obj &&
VM_BIND_OP(op) == XE_VM_BIND_OP_UNMAP_ALL) ||
XE_IOCTL_ERR(xe, addr &&
@@ -3389,6 +3411,7 @@ int xe_vm_invalidate_vma(struct xe_vma *vma)
int ret;
XE_BUG_ON(!xe_vm_in_fault_mode(vma->vm));
+ XE_WARN_ON(xe_vma_is_null(vma));
trace_xe_vma_usm_invalidate(vma);
/* Check that we don't race with page-table updates */
@@ -3451,8 +3474,11 @@ int xe_analyze_vm(struct drm_printer *p, struct xe_vm *vm, int gt_id)
for (node = rb_first(&vm->vmas); node; node = rb_next(node)) {
struct xe_vma *vma = to_xe_vma(node);
bool is_userptr = xe_vma_is_userptr(vma);
+ bool is_null = xe_vma_is_null(vma);
- if (is_userptr) {
+ if (is_null) {
+ addr = 0;
+ } else if (is_userptr) {
struct xe_res_cursor cur;
xe_res_first_sg(vma->userptr.sg, 0, XE_PAGE_SIZE,
@@ -3463,7 +3489,8 @@ int xe_analyze_vm(struct drm_printer *p, struct xe_vm *vm, int gt_id)
}
drm_printf(p, " [%016llx-%016llx] S:0x%016llx A:%016llx %s\n",
vma->start, vma->end, vma->end - vma->start + 1ull,
- addr, is_userptr ? "USR" : is_vram ? "VRAM" : "SYS");
+ addr, is_null ? "NULL" : is_userptr ? "USR" :
+ is_vram ? "VRAM" : "SYS");
}
up_read(&vm->lock);
diff --git a/drivers/gpu/drm/xe/xe_vm.h b/drivers/gpu/drm/xe/xe_vm.h
index 372f26153209..38731e200813 100644
--- a/drivers/gpu/drm/xe/xe_vm.h
+++ b/drivers/gpu/drm/xe/xe_vm.h
@@ -115,11 +115,21 @@ static inline void xe_vm_reactivate_rebind(struct xe_vm *vm)
}
}
-static inline bool xe_vma_is_userptr(struct xe_vma *vma)
+static inline bool xe_vma_is_null(struct xe_vma *vma)
+{
+ return vma->pte_flags & XE_PTE_FLAG_NULL;
+}
+
+static inline bool xe_vma_has_no_bo(struct xe_vma *vma)
{
return !vma->bo;
}
+static inline bool xe_vma_is_userptr(struct xe_vma *vma)
+{
+ return xe_vma_has_no_bo(vma) && !xe_vma_is_null(vma);
+}
+
int xe_vma_userptr_pin_pages(struct xe_vma *vma);
int xe_vma_userptr_check_repin(struct xe_vma *vma);
diff --git a/drivers/gpu/drm/xe/xe_vm_types.h b/drivers/gpu/drm/xe/xe_vm_types.h
index 6daddd29d416..f775bafe4619 100644
--- a/drivers/gpu/drm/xe/xe_vm_types.h
+++ b/drivers/gpu/drm/xe/xe_vm_types.h
@@ -31,6 +31,7 @@ struct xe_vma {
u64 end;
/** @pte_flags: pte flags for this VMA */
#define XE_PTE_FLAG_READ_ONLY BIT(0)
+#define XE_PTE_FLAG_NULL BIT(1)
u32 pte_flags;
/** @bo: BO if not a userptr, must be NULL is userptr */
diff --git a/include/uapi/drm/xe_drm.h b/include/uapi/drm/xe_drm.h
index 0ebc50beb5e5..39a1ce89732f 100644
--- a/include/uapi/drm/xe_drm.h
+++ b/include/uapi/drm/xe_drm.h
@@ -456,6 +456,14 @@ struct drm_xe_vm_bind_op {
* than differing the MAP to the page fault handler.
*/
#define XE_VM_BIND_FLAG_IMMEDIATE (0x1 << 18)
+ /*
+ * When the NULL flag is set, the page tables are setup with a special
+ * bit which indicates writes are dropped and all reads return zero. In
+ * the future, the NULL flags will only be valid for XE_VM_BIND_OP_MAP
+ * operations, the BO handle MBZ, and the BO offset MBZ. This flag is
+ * intended to implement VK sparse bindings.
+ */
+#define XE_VM_BIND_FLAG_NULL (0x1 << 19)
/** @reserved: Reserved */
__u64 reserved[2];
--
2.34.1
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