diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
index a90f796e85c03f337bcb0dbb10577cb40a70bfa7..2f3b7dc7b0e6e33976b7aef7de3ed6d9941d814a 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
@@ -679,10 +679,16 @@ __assign_mmap_offset(struct drm_i915_gem_object *obj,
return -ENODEV;
if (obj->ops->mmap_offset) {
+ if (mmap_type != I915_MMAP_TYPE_FIXED)
+ return -ENODEV;
+
*offset = obj->ops->mmap_offset(obj);
return 0;
}
+ if (mmap_type == I915_MMAP_TYPE_FIXED)
+ return -ENODEV;
+
if (mmap_type != I915_MMAP_TYPE_GTT &&
!i915_gem_object_has_struct_page(obj) &&
!i915_gem_object_has_iomem(obj))
@@ -727,7 +733,9 @@ i915_gem_dumb_mmap_offset(struct drm_file *file,
{
enum i915_mmap_type mmap_type;
- if (boot_cpu_has(X86_FEATURE_PAT))
+ if (HAS_LMEM(to_i915(dev)))
+ mmap_type = I915_MMAP_TYPE_FIXED;
+ else if (boot_cpu_has(X86_FEATURE_PAT))
mmap_type = I915_MMAP_TYPE_WC;
else if (!i915_ggtt_has_aperture(&to_i915(dev)->ggtt))
return -ENODEV;
@@ -798,6 +806,10 @@ i915_gem_mmap_offset_ioctl(struct drm_device *dev, void *data,
type = I915_MMAP_TYPE_UC;
break;
+ case I915_MMAP_OFFSET_FIXED:
+ type = I915_MMAP_TYPE_FIXED;
+ break;
+
default:
return -EINVAL;
}
@@ -968,6 +980,9 @@ int i915_gem_mmap(struct file *filp, struct vm_area_struct *vma)
vma->vm_ops = &vm_ops_cpu;
break;
+ case I915_MMAP_TYPE_FIXED:
+ GEM_WARN_ON(1);
+ fallthrough;
case I915_MMAP_TYPE_WB:
vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
vma->vm_ops = &vm_ops_cpu;
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object_types.h b/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
index ef3de2ae97236330c4498e3e417ecb4d4149409b..afbadfc5516b68408ebc075c96a3b2767fedb9ef 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
@@ -105,6 +105,7 @@ enum i915_mmap_type {
I915_MMAP_TYPE_WC,
I915_MMAP_TYPE_WB,
I915_MMAP_TYPE_UC,
+ I915_MMAP_TYPE_FIXED,
};
struct i915_mmap_offset {
diff --git a/drivers/gpu/drm/i915/gem/selftests/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/selftests/i915_gem_mman.c
index fda017c19ef6ecdd23ea987f649ec02d03df0d69..0b2b73d8a36480f4692f08fd488f7ccd9f97e0cd 100644
--- a/drivers/gpu/drm/i915/gem/selftests/i915_gem_mman.c
+++ b/drivers/gpu/drm/i915/gem/selftests/i915_gem_mman.c
@@ -573,6 +573,14 @@ static int make_obj_busy(struct drm_i915_gem_object *obj)
return 0;
}
+static enum i915_mmap_type default_mapping(struct drm_i915_private *i915)
+{
+ if (HAS_LMEM(i915))
+ return I915_MMAP_TYPE_FIXED;
+
+ return I915_MMAP_TYPE_GTT;
+}
+
static bool assert_mmap_offset(struct drm_i915_private *i915,
unsigned long size,
int expected)
@@ -585,7 +593,7 @@ static bool assert_mmap_offset(struct drm_i915_private *i915,
if (IS_ERR(obj))
return expected && expected == PTR_ERR(obj);
- ret = __assign_mmap_offset(obj, I915_MMAP_TYPE_GTT, &offset, NULL);
+ ret = __assign_mmap_offset(obj, default_mapping(i915), &offset, NULL);
i915_gem_object_put(obj);
return ret == expected;
@@ -689,7 +697,7 @@ static int igt_mmap_offset_exhaustion(void *arg)
goto out;
}
- err = __assign_mmap_offset(obj, I915_MMAP_TYPE_GTT, &offset, NULL);
+ err = __assign_mmap_offset(obj, default_mapping(i915), &offset, NULL);
if (err) {
pr_err("Unable to insert object into reclaimed hole\n");
goto err_obj;
@@ -831,8 +839,14 @@ static int wc_check(struct drm_i915_gem_object *obj)
static bool can_mmap(struct drm_i915_gem_object *obj, enum i915_mmap_type type)
{
+ struct drm_i915_private *i915 = to_i915(obj->base.dev);
bool no_map;
+ if (HAS_LMEM(i915))
+ return type == I915_MMAP_TYPE_FIXED;
+ else if (type == I915_MMAP_TYPE_FIXED)
+ return false;
+
if (type == I915_MMAP_TYPE_GTT &&
!i915_ggtt_has_aperture(&to_i915(obj->base.dev)->ggtt))
return false;
@@ -970,6 +984,8 @@ static int igt_mmap(void *arg)
err = __igt_mmap(i915, obj, I915_MMAP_TYPE_GTT);
if (err == 0)
err = __igt_mmap(i915, obj, I915_MMAP_TYPE_WC);
+ if (err == 0)
+ err = __igt_mmap(i915, obj, I915_MMAP_TYPE_FIXED);
i915_gem_object_put(obj);
if (err)
@@ -987,6 +1003,7 @@ static const char *repr_mmap_type(enum i915_mmap_type type)
case I915_MMAP_TYPE_WB: return "wb";
case I915_MMAP_TYPE_WC: return "wc";
case I915_MMAP_TYPE_UC: return "uc";
+ case I915_MMAP_TYPE_FIXED: return "fixed";
default: return "unknown";
}
}
@@ -1100,6 +1117,8 @@ static int igt_mmap_access(void *arg)
err = __igt_mmap_access(i915, obj, I915_MMAP_TYPE_WC);
if (err == 0)
err = __igt_mmap_access(i915, obj, I915_MMAP_TYPE_UC);
+ if (err == 0)
+ err = __igt_mmap_access(i915, obj, I915_MMAP_TYPE_FIXED);
i915_gem_object_put(obj);
if (err)
@@ -1241,6 +1260,8 @@ static int igt_mmap_gpu(void *arg)
err = __igt_mmap_gpu(i915, obj, I915_MMAP_TYPE_GTT);
if (err == 0)
err = __igt_mmap_gpu(i915, obj, I915_MMAP_TYPE_WC);
+ if (err == 0)
+ err = __igt_mmap_gpu(i915, obj, I915_MMAP_TYPE_FIXED);
i915_gem_object_put(obj);
if (err)
@@ -1396,6 +1417,8 @@ static int igt_mmap_revoke(void *arg)
err = __igt_mmap_revoke(i915, obj, I915_MMAP_TYPE_GTT);
if (err == 0)
err = __igt_mmap_revoke(i915, obj, I915_MMAP_TYPE_WC);
+ if (err == 0)
+ err = __igt_mmap_revoke(i915, obj, I915_MMAP_TYPE_FIXED);
i915_gem_object_put(obj);
if (err)
diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
index e20eeeca7a1cb1358b45f9cfee93384c560690a0..0aea82657cdc4137acd817bb9db965165f778dfc 100644
--- a/include/uapi/drm/i915_drm.h
+++ b/include/uapi/drm/i915_drm.h
@@ -849,31 +849,56 @@ struct drm_i915_gem_mmap_gtt {
__u64 offset;
};
+/**
+ * struct drm_i915_gem_mmap_offset - Retrieve an offset so we can mmap this buffer object.
+ *
+ * This struct is passed as argument to the `DRM_IOCTL_I915_GEM_MMAP_OFFSET` ioctl,
+ * and is used to retrieve the fake offset to mmap an object specified by &handle.
+ *
+ * The legacy way of using `DRM_IOCTL_I915_GEM_MMAP` is removed on gen12+.
+ * `DRM_IOCTL_I915_GEM_MMAP_GTT` is an older supported alias to this struct, but will behave
+ * as setting the &extensions to 0, and &flags to `I915_MMAP_OFFSET_GTT`.
+ */
struct drm_i915_gem_mmap_offset {
- /** Handle for the object being mapped. */
+ /** @handle: Handle for the object being mapped. */
__u32 handle;
+ /** @pad: Must be zero */
__u32 pad;
/**
- * Fake offset to use for subsequent mmap call
+ * @offset: The fake offset to use for subsequent mmap call
*
* This is a fixed-size type for 32/64 compatibility.
*/
__u64 offset;
/**
- * Flags for extended behaviour.
+ * @flags: Flags for extended behaviour.
*
- * It is mandatory that one of the MMAP_OFFSET types
- * (GTT, WC, WB, UC, etc) should be included.
+ * It is mandatory that one of the `MMAP_OFFSET` types
+ * should be included:
+ *
+ * - `I915_MMAP_OFFSET_GTT`: Use mmap with the object bound to GTT. (Write-Combined)
+ * - `I915_MMAP_OFFSET_WC`: Use Write-Combined caching.
+ * - `I915_MMAP_OFFSET_WB`: Use Write-Back caching.
+ * - `I915_MMAP_OFFSET_FIXED`: Use object placement to determine caching.
+ *
+ * On devices with local memory `I915_MMAP_OFFSET_FIXED` is the only valid
+ * type. On devices without local memory, this caching mode is invalid.
+ *
+ * As caching mode when specifying `I915_MMAP_OFFSET_FIXED`, WC or WB will
+ * be used, depending on the object placement on creation. WB will be used
+ * when the object can only exist in system memory, WC otherwise.
*/
__u64 flags;
-#define I915_MMAP_OFFSET_GTT 0
-#define I915_MMAP_OFFSET_WC 1
-#define I915_MMAP_OFFSET_WB 2
-#define I915_MMAP_OFFSET_UC 3
- /*
- * Zero-terminated chain of extensions.
+#define I915_MMAP_OFFSET_GTT 0
+#define I915_MMAP_OFFSET_WC 1
+#define I915_MMAP_OFFSET_WB 2
+#define I915_MMAP_OFFSET_UC 3
+#define I915_MMAP_OFFSET_FIXED 4
+
+ /**
+ * @extensions: Zero-terminated chain of extensions.
*
* No current extensions defined; mbz.
*/