On Sat, Jun 25, 2022 at 8:49 PM Niranjana Vishwanathapura <niranjana.vishwanathapura@xxxxxxxxx> wrote:
VM_BIND and related uapi definitions
v2: Reduce the scope to simple Mesa use case.
v3: Expand VM_UNBIND documentation and add
I915_GEM_VM_BIND/UNBIND_FENCE_VALID
and I915_GEM_VM_BIND_TLB_FLUSH flags.
v4: Remove I915_GEM_VM_BIND_TLB_FLUSH flag and add additional
documentation for vm_bind/unbind.
v5: Remove TLB flush requirement on VM_UNBIND.
Add version support to stage implementation.
v6: Define and use drm_i915_gem_timeline_fence structure for
all timeline fences.
v7: Rename I915_PARAM_HAS_VM_BIND to I915_PARAM_VM_BIND_VERSION.
Update documentation on async vm_bind/unbind and versioning.
Remove redundant vm_bind/unbind FENCE_VALID flag, execbuf3
batch_count field and I915_EXEC3_SECURE flag.
Signed-off-by: Niranjana Vishwanathapura <niranjana.vishwanathapura@xxxxxxxxx>
Reviewed-by: Daniel Vetter <daniel.vetter@xxxxxxxx>
---
Documentation/gpu/rfc/i915_vm_bind.h | 280 +++++++++++++++++++++++++++
1 file changed, 280 insertions(+)
create mode 100644 Documentation/gpu/rfc/i915_vm_bind.h
diff --git a/Documentation/gpu/rfc/i915_vm_bind.h b/Documentation/gpu/rfc/i915_vm_bind.h
new file mode 100644
index 000000000000..a93e08bceee6
--- /dev/null
+++ b/Documentation/gpu/rfc/i915_vm_bind.h
@@ -0,0 +1,280 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2022 Intel Corporation
+ */
+
+/**
+ * DOC: I915_PARAM_VM_BIND_VERSION
+ *
+ * VM_BIND feature version supported.
+ * See typedef drm_i915_getparam_t param.
+ *
+ * Specifies the VM_BIND feature version supported.
+ * The following versions of VM_BIND have been defined:
+ *
+ * 0: No VM_BIND support.
+ *
+ * 1: In VM_UNBIND calls, the UMD must specify the exact mappings created
+ * previously with VM_BIND, the ioctl will not support unbinding multiple
+ * mappings or splitting them. Similarly, VM_BIND calls will not replace
+ * any existing mappings.
+ *
+ * 2: The restrictions on unbinding partial or multiple mappings is
+ * lifted, Similarly, binding will replace any mappings in the given range.
+ *
+ * See struct drm_i915_gem_vm_bind and struct drm_i915_gem_vm_unbind.
+ */
+#define I915_PARAM_VM_BIND_VERSION 57
+
+/**
+ * DOC: I915_VM_CREATE_FLAGS_USE_VM_BIND
+ *
+ * Flag to opt-in for VM_BIND mode of binding during VM creation.
+ * See struct drm_i915_gem_vm_control flags.
+ *
+ * The older execbuf2 ioctl will not support VM_BIND mode of operation.
+ * For VM_BIND mode, we have new execbuf3 ioctl which will not accept any
+ * execlist (See struct drm_i915_gem_execbuffer3 for more details).
+ */
+#define I915_VM_CREATE_FLAGS_USE_VM_BIND (1 << 0)
+
+/* VM_BIND related ioctls */
+#define DRM_I915_GEM_VM_BIND 0x3d
+#define DRM_I915_GEM_VM_UNBIND 0x3e
+#define DRM_I915_GEM_EXECBUFFER3 0x3f
+
+#define DRM_IOCTL_I915_GEM_VM_BIND DRM_IOWR(DRM_COMMAND_BASE + DRM_I915_GEM_VM_BIND, struct drm_i915_gem_vm_bind)
+#define DRM_IOCTL_I915_GEM_VM_UNBIND DRM_IOWR(DRM_COMMAND_BASE + DRM_I915_GEM_VM_UNBIND, struct drm_i915_gem_vm_bind)
+#define DRM_IOCTL_I915_GEM_EXECBUFFER3 DRM_IOWR(DRM_COMMAND_BASE + DRM_I915_GEM_EXECBUFFER3, struct drm_i915_gem_execbuffer3)
+
+/**
+ * struct drm_i915_gem_timeline_fence - An input or output timeline fence.
+ *
+ * The operation will wait for input fence to signal.
+ *
+ * The returned output fence will be signaled after the completion of the
+ * operation.
+ */
+struct drm_i915_gem_timeline_fence {
+ /** @handle: User's handle for a drm_syncobj to wait on or signal. */
+ __u32 handle;
+
+ /**
+ * @flags: Supported flags are:
+ *
+ * I915_TIMELINE_FENCE_WAIT:
+ * Wait for the input fence before the operation.
+ *
+ * I915_TIMELINE_FENCE_SIGNAL:
+ * Return operation completion fence as output.
+ */
+ __u32 flags;
+#define I915_TIMELINE_FENCE_WAIT (1 << 0)
+#define I915_TIMELINE_FENCE_SIGNAL (1 << 1)
+#define __I915_TIMELINE_FENCE_UNKNOWN_FLAGS (-(I915_TIMELINE_FENCE_SIGNAL << 1))
+
+ /**
+ * @value: A point in the timeline.
+ * Value must be 0 for a binary drm_syncobj. A Value of 0 for a
+ * timeline drm_syncobj is invalid as it turns a drm_syncobj into a
+ * binary one.
+ */
+ __u64 value;
+};
+
+/**
+ * struct drm_i915_gem_vm_bind - VA to object mapping to bind.
+ *
+ * This structure is passed to VM_BIND ioctl and specifies the mapping of GPU
+ * virtual address (VA) range to the section of an object that should be bound
+ * in the device page table of the specified address space (VM).
+ * The VA range specified must be unique (ie., not currently bound) and can
+ * be mapped to whole object or a section of the object (partial binding).
+ * Multiple VA mappings can be created to the same section of the object
+ * (aliasing).
+ *
+ * The @start, @offset and @length must be 4K page aligned. However the DG2
+ * and XEHPSDV has 64K page size for device local-memory and has compact page
+ * table. On those platforms, for binding device local-memory objects, the
+ * @start must be 2M aligned, @offset and @length must be 64K aligned.
+ * Also, for such mappings, i915 will reserve the whole 2M range for it so as
+ * to not allow multiple mappings in that 2M range (Compact page tables do not
+ * allow 64K page and 4K page bindings in the same 2M range).
+ *
+ * Error code -EINVAL will be returned if @start, @offset and @length are not
+ * properly aligned. In version 1 (See I915_PARAM_VM_BIND_VERSION), error code
+ * -ENOSPC will be returned if the VA range specified can't be reserved.
+ *
+ * VM_BIND/UNBIND ioctl calls executed on different CPU threads concurrently
+ * are not ordered. Furthermore, parts of the VM_BIND operation can be done
+ * asynchronously, if valid @fence is specified.
+ */
+struct drm_i915_gem_vm_bind {
+ /** @vm_id: VM (address space) id to bind */
+ __u32 vm_id;
+
+ /** @handle: Object handle */
+ __u32 handle;
+
+ /** @start: Virtual Address start to bind */
+ __u64 start;
+
+ /** @offset: Offset in object to bind */
+ __u64 offset;
+
+ /** @length: Length of mapping to bind */
+ __u64 length;
+
+ /**
+ * @flags: Supported flags are:
+ *
+ * I915_GEM_VM_BIND_READONLY:
+ * Mapping is read-only.
+ *
+ * I915_GEM_VM_BIND_CAPTURE:
+ * Capture this mapping in the dump upon GPU error.
+ */
+ __u64 flags;
+#define I915_GEM_VM_BIND_READONLY (1 << 1)
+#define I915_GEM_VM_BIND_CAPTURE (1 << 2)
+
+ /**
+ * @fence: Timeline fence for bind completion signaling.
+ *
+ * It is an out fence, hence using I915_TIMELINE_FENCE_WAIT flag
+ * is invalid, and an error will be returned.
+ */
+ struct drm_i915_gem_timeline_fence fence;
Why a single fence and not an array of fences? If Mesa wants to use the out fences for signalling VkSemaphores on the sparse binding queue, we need N of them. We can still have the "zero fences means block" behavior.
--Jason
+
+ /**
+ * @extensions: Zero-terminated chain of extensions.
+ *
+ * For future extensions. See struct i915_user_extension.
+ */
+ __u64 extensions;
+};
+
+/**
+ * struct drm_i915_gem_vm_unbind - VA to object mapping to unbind.
+ *
+ * This structure is passed to VM_UNBIND ioctl and specifies the GPU virtual
+ * address (VA) range that should be unbound from the device page table of the
+ * specified address space (VM). VM_UNBIND will force unbind the specified
+ * range from device page table without waiting for any GPU job to complete.
+ * It is UMDs responsibility to ensure the mapping is no longer in use before
+ * calling VM_UNBIND.
+ *
+ * If the specified mapping is not found, the ioctl will simply return without
+ * any error.
+ *
+ * VM_BIND/UNBIND ioctl calls executed on different CPU threads concurrently
+ * are not ordered. Furthermore, parts of the VM_UNBIND operation can be done
+ * asynchronously, if valid @fence is specified.
+ */
+struct drm_i915_gem_vm_unbind {
+ /** @vm_id: VM (address space) id to bind */
+ __u32 vm_id;
+
+ /** @rsvd: Reserved, MBZ */
+ __u32 rsvd;
+
+ /** @start: Virtual Address start to unbind */
+ __u64 start;
+
+ /** @length: Length of mapping to unbind */
+ __u64 length;
+
+ /** @flags: Currently reserved, MBZ */
+ __u64 flags;
+
+ /**
+ * @fence: Timeline fence for unbind completion signaling.
+ *
+ * It is an out fence, hence using I915_TIMELINE_FENCE_WAIT flag
+ * is invalid, and an error will be returned.
+ */
+ struct drm_i915_gem_timeline_fence fence;
+
+ /**
+ * @extensions: Zero-terminated chain of extensions.
+ *
+ * For future extensions. See struct i915_user_extension.
+ */
+ __u64 extensions;
+};
+
+/**
+ * struct drm_i915_gem_execbuffer3 - Structure for DRM_I915_GEM_EXECBUFFER3
+ * ioctl.
+ *
+ * DRM_I915_GEM_EXECBUFFER3 ioctl only works in VM_BIND mode and VM_BIND mode
+ * only works with this ioctl for submission.
+ * See I915_VM_CREATE_FLAGS_USE_VM_BIND.
+ */
+struct drm_i915_gem_execbuffer3 {
+ /**
+ * @ctx_id: Context id
+ *
+ * Only contexts with user engine map are allowed.
+ */
+ __u32 ctx_id;
+
+ /**
+ * @engine_idx: Engine index
+ *
+ * An index in the user engine map of the context specified by @ctx_id.
+ */
+ __u32 engine_idx;
+
+ /**
+ * @batch_address: Batch gpu virtual address/es.
+ *
+ * For normal submission, it is the gpu virtual address of the batch
+ * buffer. For parallel submission, it is a pointer to an array of
+ * batch buffer gpu virtual addresses with array size equal to the
+ * number of (parallel) engines involved in that submission (See
+ * struct i915_context_engines_parallel_submit).
+ */
+ __u64 batch_address;
+
+ /** @flags: Currently reserved, MBZ */
+ __u64 flags;
+
+ /** @rsvd1: Reserved, MBZ */
+ __u32 rsvd1;
+
+ /** @fence_count: Number of fences in @timeline_fences array. */
+ __u32 fence_count;
+
+ /**
+ * @timeline_fences: Pointer to an array of timeline fences.
+ *
+ * Timeline fences are of format struct drm_i915_gem_timeline_fence.
+ */
+ __u64 timeline_fences;
+
+ /** @rsvd2: Reserved, MBZ */
+ __u64 rsvd2;
+
+ /**
+ * @extensions: Zero-terminated chain of extensions.
+ *
+ * For future extensions. See struct i915_user_extension.
+ */
+ __u64 extensions;
+};
+
+/**
+ * struct drm_i915_gem_create_ext_vm_private - Extension to make the object
+ * private to the specified VM.
+ *
+ * See struct drm_i915_gem_create_ext.
+ */
+struct drm_i915_gem_create_ext_vm_private {
+#define I915_GEM_CREATE_EXT_VM_PRIVATE 2
+ /** @base: Extension link. See struct i915_user_extension. */
+ struct i915_user_extension base;
+
+ /** @vm_id: Id of the VM to which the object is private */
+ __u32 vm_id;
+};
--
2.21.0.rc0.32.g243a4c7e27
