From: Asahi Lina <lina+kernel@asahilina.net>
drm_gpuva objects have a flags field. Currently, this can be managed by
drivers out-of-band, without any special handling in drm_gpuvm.
To be able to introduce flags that do affect the logic in the drm_gpuvm
core, we need to plumb it through the map calls. This will allow the
core to check the flags on map and alter the merge/split logic depending
on the requested flags and the flags of the existing drm_gpuva ranges
that are being split.
Signed-off-by: Asahi Lina <lina+kernel@asahilina.net>
Signed-off-by: Caterina Shablia <caterina.shablia@collabora.com>
---
drivers/gpu/drm/drm_gpuvm.c | 14 ++++++++++++--
include/drm/drm_gpuvm.h | 18 ++++++++++++++++++
2 files changed, 30 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/drm_gpuvm.c b/drivers/gpu/drm/drm_gpuvm.c
index 4af7b71abcb4..0d9c821d1b34 100644
--- a/drivers/gpu/drm/drm_gpuvm.c
+++ b/drivers/gpu/drm/drm_gpuvm.c
@@ -2386,6 +2386,7 @@ static bool can_merge(struct drm_gpuvm *gpuvm, const struct drm_gpuva *va,
.va.range = va->va.range,
.gem.offset = va->gem.offset,
.gem.obj = va->gem.obj,
+ .flags = va->flags,
};
const struct drm_gpuva_op_map *a = new_map, *b = &existing_map;
@@ -2395,6 +2396,10 @@ static bool can_merge(struct drm_gpuvm *gpuvm, const struct drm_gpuva *va,
if (a->gem.obj != b->gem.obj || !a->gem.obj)
return false;
+ /* For two VAs to be merged, their flags must be compatible */
+ if ((a->flags & VA_MERGE_MUST_MATCH_FLAGS) != (b->flags & VA_MERGE_MUST_MATCH_FLAGS))
+ return false;
+
/* Order VAs for the rest of the checks. */
if (a->va.addr > b->va.addr)
swap(a, b);
@@ -2459,6 +2464,7 @@ __drm_gpuvm_sm_map(struct drm_gpuvm *gpuvm,
.va.range = range - req_range,
.gem.obj = obj,
.gem.offset = offset + req_range,
+ .flags = va->flags,
};
struct drm_gpuva_op_unmap u = {
.va = va,
@@ -2480,6 +2486,7 @@ __drm_gpuvm_sm_map(struct drm_gpuvm *gpuvm,
.va.range = ls_range,
.gem.obj = obj,
.gem.offset = offset,
+ .flags = va->flags,
};
struct drm_gpuva_op_unmap u = { .va = va };
@@ -2519,8 +2526,8 @@ __drm_gpuvm_sm_map(struct drm_gpuvm *gpuvm,
.va.addr = req_end,
.va.range = end - req_end,
.gem.obj = obj,
- .gem.offset = offset + ls_range +
- req_range,
+ .gem.offset = offset + ls_range + req_range,
+ .flags = va->flags,
};
ret = op_remap_cb(ops, priv, &p, &n, &u);
@@ -2554,6 +2561,7 @@ __drm_gpuvm_sm_map(struct drm_gpuvm *gpuvm,
.va.range = end - req_end,
.gem.obj = obj,
.gem.offset = offset + req_end - addr,
+ .flags = va->flags,
};
struct drm_gpuva_op_unmap u = {
.va = va,
@@ -2605,6 +2613,7 @@ __drm_gpuvm_sm_unmap(struct drm_gpuvm *gpuvm,
prev.va.range = req_addr - addr;
prev.gem.obj = obj;
prev.gem.offset = offset;
+ prev.flags = va->flags;
prev_split = true;
}
@@ -2614,6 +2623,7 @@ __drm_gpuvm_sm_unmap(struct drm_gpuvm *gpuvm,
next.va.range = end - req_end;
next.gem.obj = obj;
next.gem.offset = offset + (req_end - addr);
+ next.flags = va->flags;
next_split = true;
}
diff --git a/include/drm/drm_gpuvm.h b/include/drm/drm_gpuvm.h
index 6a6e64cd2cce..5bf37deb282d 100644
--- a/include/drm/drm_gpuvm.h
+++ b/include/drm/drm_gpuvm.h
@@ -63,6 +63,8 @@ enum drm_gpuva_flags {
DRM_GPUVA_USERBITS = (1 << 2),
};
+#define VA_MERGE_MUST_MATCH_FLAGS (DRM_GPUVA_SPARSE)
+
/**
* struct drm_gpuva - structure to track a GPU VA mapping
*
@@ -886,6 +888,11 @@ struct drm_gpuva_op_map {
*/
struct drm_gem_object *obj;
} gem;
+
+ /**
+ * @flags: requested flags for the &drm_gpuva for this mapping
+ */
+ enum drm_gpuva_flags flags;
};
/**
@@ -1124,6 +1131,7 @@ void drm_gpuva_ops_free(struct drm_gpuvm *gpuvm,
static inline void drm_gpuva_init_from_op(struct drm_gpuva *va,
const struct drm_gpuva_op_map *op)
{
+ va->flags = op->flags;
va->va.addr = op->va.addr;
va->va.range = op->va.range;
va->gem.obj = op->gem.obj;
@@ -1249,6 +1257,16 @@ struct drm_gpuvm_ops {
* used.
*/
int (*sm_step_unmap)(struct drm_gpuva_op *op, void *priv);
+
+ /**
+ * @sm_can_merge_flags: called during &drm_gpuvm_sm_map
+ *
+ * This callback is called to determine whether two va ranges can be merged,
+ * based on their flags.
+ *
+ * If NULL, va ranges can only be merged if their flags are equal.
+ */
+ bool (*sm_can_merge_flags)(enum drm_gpuva_flags a, enum drm_gpuva_flags b);
};
int drm_gpuvm_sm_map(struct drm_gpuvm *gpuvm, void *priv,
--
2.53.0On Fri Mar 13, 2026 at 4:09 PM CET, Adrián Larumbe wrote:
> From: Asahi Lina <lina+kernel@asahilina.net>
>
> drm_gpuva objects have a flags field. Currently, this can be managed by
> drivers out-of-band, without any special handling in drm_gpuvm.
>
> To be able to introduce flags that do affect the logic in the drm_gpuvm
> core, we need to plumb it through the map calls. This will allow the
> core to check the flags on map and alter the merge/split logic depending
> on the requested flags and the flags of the existing drm_gpuva ranges
> that are being split.
>
> Signed-off-by: Asahi Lina <lina+kernel@asahilina.net>
> Signed-off-by: Caterina Shablia <caterina.shablia@collabora.com>
Missing Signed-off-by.
> ---
> drivers/gpu/drm/drm_gpuvm.c | 14 ++++++++++++--
> include/drm/drm_gpuvm.h | 18 ++++++++++++++++++
> 2 files changed, 30 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_gpuvm.c b/drivers/gpu/drm/drm_gpuvm.c
> index 4af7b71abcb4..0d9c821d1b34 100644
> --- a/drivers/gpu/drm/drm_gpuvm.c
> +++ b/drivers/gpu/drm/drm_gpuvm.c
> @@ -2386,6 +2386,7 @@ static bool can_merge(struct drm_gpuvm *gpuvm, const struct drm_gpuva *va,
> .va.range = va->va.range,
> .gem.offset = va->gem.offset,
> .gem.obj = va->gem.obj,
> + .flags = va->flags,
> };
> const struct drm_gpuva_op_map *a = new_map, *b = &existing_map;
>
> @@ -2395,6 +2396,10 @@ static bool can_merge(struct drm_gpuvm *gpuvm, const struct drm_gpuva *va,
> if (a->gem.obj != b->gem.obj || !a->gem.obj)
> return false;
>
> + /* For two VAs to be merged, their flags must be compatible */
> + if ((a->flags & VA_MERGE_MUST_MATCH_FLAGS) != (b->flags & VA_MERGE_MUST_MATCH_FLAGS))
> + return false;
This has nothing to do with this patch, the commit message only talks about
adding flags to struct drm_gpuva_op_map.
Please create a new patch for further changes, v4 of this was fine as is.
> +
> /* Order VAs for the rest of the checks. */
> if (a->va.addr > b->va.addr)
> swap(a, b);
> @@ -2459,6 +2464,7 @@ __drm_gpuvm_sm_map(struct drm_gpuvm *gpuvm,
> .va.range = range - req_range,
> .gem.obj = obj,
> .gem.offset = offset + req_range,
> + .flags = va->flags,
> };
> struct drm_gpuva_op_unmap u = {
> .va = va,
> @@ -2480,6 +2486,7 @@ __drm_gpuvm_sm_map(struct drm_gpuvm *gpuvm,
> .va.range = ls_range,
> .gem.obj = obj,
> .gem.offset = offset,
> + .flags = va->flags,
> };
> struct drm_gpuva_op_unmap u = { .va = va };
>
> @@ -2519,8 +2526,8 @@ __drm_gpuvm_sm_map(struct drm_gpuvm *gpuvm,
> .va.addr = req_end,
> .va.range = end - req_end,
> .gem.obj = obj,
> - .gem.offset = offset + ls_range +
> - req_range,
> + .gem.offset = offset + ls_range + req_range,
Spurious change.
> + .flags = va->flags,
> };
>
> ret = op_remap_cb(ops, priv, &p, &n, &u);
> @@ -2554,6 +2561,7 @@ __drm_gpuvm_sm_map(struct drm_gpuvm *gpuvm,
> .va.range = end - req_end,
> .gem.obj = obj,
> .gem.offset = offset + req_end - addr,
> + .flags = va->flags,
> };
> struct drm_gpuva_op_unmap u = {
> .va = va,
> @@ -2605,6 +2613,7 @@ __drm_gpuvm_sm_unmap(struct drm_gpuvm *gpuvm,
> prev.va.range = req_addr - addr;
> prev.gem.obj = obj;
> prev.gem.offset = offset;
> + prev.flags = va->flags;
>
> prev_split = true;
> }
> @@ -2614,6 +2623,7 @@ __drm_gpuvm_sm_unmap(struct drm_gpuvm *gpuvm,
> next.va.range = end - req_end;
> next.gem.obj = obj;
> next.gem.offset = offset + (req_end - addr);
> + next.flags = va->flags;
>
> next_split = true;
> }
> diff --git a/include/drm/drm_gpuvm.h b/include/drm/drm_gpuvm.h
> index 6a6e64cd2cce..5bf37deb282d 100644
> --- a/include/drm/drm_gpuvm.h
> +++ b/include/drm/drm_gpuvm.h
> @@ -63,6 +63,8 @@ enum drm_gpuva_flags {
> DRM_GPUVA_USERBITS = (1 << 2),
> };
>
> +#define VA_MERGE_MUST_MATCH_FLAGS (DRM_GPUVA_SPARSE)
Please drop this indirection if the only criteria is that both must be sparse.
> +
> /**
> * struct drm_gpuva - structure to track a GPU VA mapping
> *
> @@ -886,6 +888,11 @@ struct drm_gpuva_op_map {
> */
> struct drm_gem_object *obj;
> } gem;
> +
> + /**
> + * @flags: requested flags for the &drm_gpuva for this mapping
> + */
> + enum drm_gpuva_flags flags;
> };
>
> /**
> @@ -1124,6 +1131,7 @@ void drm_gpuva_ops_free(struct drm_gpuvm *gpuvm,
> static inline void drm_gpuva_init_from_op(struct drm_gpuva *va,
> const struct drm_gpuva_op_map *op)
> {
> + va->flags = op->flags;
> va->va.addr = op->va.addr;
> va->va.range = op->va.range;
> va->gem.obj = op->gem.obj;
> @@ -1249,6 +1257,16 @@ struct drm_gpuvm_ops {
> * used.
> */
> int (*sm_step_unmap)(struct drm_gpuva_op *op, void *priv);
> +
> + /**
> + * @sm_can_merge_flags: called during &drm_gpuvm_sm_map
> + *
> + * This callback is called to determine whether two va ranges can be merged,
> + * based on their flags.
> + *
> + * If NULL, va ranges can only be merged if their flags are equal.
> + */
> + bool (*sm_can_merge_flags)(enum drm_gpuva_flags a, enum drm_gpuva_flags b);
Again, this has nothing to do with this commit, please add a separate patch for
this with a proper commit message explaining the motivation.
Also, this callback appears to be unused and seems to contradict the static
check for compatible merge flags in the hunk above.
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