drm/nouveau: new VM_BIND uAPI interfaces

This commit provides the interfaces for the new UAPI motivated by the
Vulkan API. It allows user mode drivers (UMDs) to:

1) Initialize a GPU virtual address (VA) space via the new
   DRM_IOCTL_NOUVEAU_VM_INIT ioctl. UMDs can provide a kernel reserved
   VA area.

2) Bind and unbind GPU VA space mappings via the new
   DRM_IOCTL_NOUVEAU_VM_BIND ioctl.

3) Execute push buffers with the new DRM_IOCTL_NOUVEAU_EXEC ioctl.

Both, DRM_IOCTL_NOUVEAU_VM_BIND and DRM_IOCTL_NOUVEAU_EXEC support
asynchronous processing with DRM syncobjs as synchronization mechanism.

The default DRM_IOCTL_NOUVEAU_VM_BIND is synchronous processing,
DRM_IOCTL_NOUVEAU_EXEC supports asynchronous processing only.
Reviewed-by: Faith Ekstrand <faith.ekstrand@collabora.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Co-developed-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Danilo Krummrich <dakr@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230804182406.5222-4-dakr@redhat.com

Documentation/gpu/driver-uapi.rst

@@ -6,3 +6,11 @@ drm/i915 uAPI
 =============
 
 .. kernel-doc:: include/uapi/drm/i915_drm.h
+
+drm/nouveau uAPI
+================
+
+VM_BIND / EXEC uAPI
+-------------------
+
+.. kernel-doc:: include/uapi/drm/nouveau_drm.h

include/uapi/drm/nouveau_drm.h

@@ -76,6 +76,8 @@ struct drm_nouveau_channel_free {
 #define NOUVEAU_GEM_DOMAIN_GART      (1 << 2)
 #define NOUVEAU_GEM_DOMAIN_MAPPABLE  (1 << 3)
 #define NOUVEAU_GEM_DOMAIN_COHERENT  (1 << 4)
+/* The BO will never be shared via import or export. */
+#define NOUVEAU_GEM_DOMAIN_NO_SHARE  (1 << 5)
 
 #define NOUVEAU_GEM_TILE_COMP        0x00030000 /* nv50-only */
 #define NOUVEAU_GEM_TILE_LAYOUT_MASK 0x0000ff00
@@ -164,6 +166,215 @@ struct drm_nouveau_gem_cpu_fini {
 	__u32 handle;
 };
 
+/**
+ * struct drm_nouveau_sync - sync object
+ *
+ * This structure serves as synchronization mechanism for (potentially)
+ * asynchronous operations such as EXEC or VM_BIND.
+ */
+struct drm_nouveau_sync {
+	/**
+	 * @flags: the flags for a sync object
+	 *
+	 * The first 8 bits are used to determine the type of the sync object.
+	 */
+	__u32 flags;
+#define DRM_NOUVEAU_SYNC_SYNCOBJ 0x0
+#define DRM_NOUVEAU_SYNC_TIMELINE_SYNCOBJ 0x1
+#define DRM_NOUVEAU_SYNC_TYPE_MASK 0xf
+	/**
+	 * @handle: the handle of the sync object
+	 */
+	__u32 handle;
+	/**
+	 * @timeline_value:
+	 *
+	 * The timeline point of the sync object in case the syncobj is of
+	 * type DRM_NOUVEAU_SYNC_TIMELINE_SYNCOBJ.
+	 */
+	__u64 timeline_value;
+};
+
+/**
+ * struct drm_nouveau_vm_init - GPU VA space init structure
+ *
+ * Used to initialize the GPU's VA space for a user client, telling the kernel
+ * which portion of the VA space is managed by the UMD and kernel respectively.
+ *
+ * For the UMD to use the VM_BIND uAPI, this must be called before any BOs or
+ * channels are created; if called afterwards DRM_IOCTL_NOUVEAU_VM_INIT fails
+ * with -ENOSYS.
+ */
+struct drm_nouveau_vm_init {
+	/**
+	 * @kernel_managed_addr: start address of the kernel managed VA space
+	 * region
+	 */
+	__u64 kernel_managed_addr;
+	/**
+	 * @kernel_managed_size: size of the kernel managed VA space region in
+	 * bytes
+	 */
+	__u64 kernel_managed_size;
+};
+
+/**
+ * struct drm_nouveau_vm_bind_op - VM_BIND operation
+ *
+ * This structure represents a single VM_BIND operation. UMDs should pass
+ * an array of this structure via struct drm_nouveau_vm_bind's &op_ptr field.
+ */
+struct drm_nouveau_vm_bind_op {
+	/**
+	 * @op: the operation type
+	 */
+	__u32 op;
+/**
+ * @DRM_NOUVEAU_VM_BIND_OP_MAP:
+ *
+ * Map a GEM object to the GPU's VA space. Optionally, the
+ * &DRM_NOUVEAU_VM_BIND_SPARSE flag can be passed to instruct the kernel to
+ * create sparse mappings for the given range.
+ */
+#define DRM_NOUVEAU_VM_BIND_OP_MAP 0x0
+/**
+ * @DRM_NOUVEAU_VM_BIND_OP_UNMAP:
+ *
+ * Unmap an existing mapping in the GPU's VA space. If the region the mapping
+ * is located in is a sparse region, new sparse mappings are created where the
+ * unmapped (memory backed) mapping was mapped previously. To remove a sparse
+ * region the &DRM_NOUVEAU_VM_BIND_SPARSE must be set.
+ */
+#define DRM_NOUVEAU_VM_BIND_OP_UNMAP 0x1
+	/**
+	 * @flags: the flags for a &drm_nouveau_vm_bind_op
+	 */
+	__u32 flags;
+/**
+ * @DRM_NOUVEAU_VM_BIND_SPARSE:
+ *
+ * Indicates that an allocated VA space region should be sparse.
+ */
+#define DRM_NOUVEAU_VM_BIND_SPARSE (1 << 8)
+	/**
+	 * @handle: the handle of the DRM GEM object to map
+	 */
+	__u32 handle;
+	/**
+	 * @pad: 32 bit padding, should be 0
+	 */
+	__u32 pad;
+	/**
+	 * @addr:
+	 *
+	 * the address the VA space region or (memory backed) mapping should be mapped to
+	 */
+	__u64 addr;
+	/**
+	 * @bo_offset: the offset within the BO backing the mapping
+	 */
+	__u64 bo_offset;
+	/**
+	 * @range: the size of the requested mapping in bytes
+	 */
+	__u64 range;
+};
+
+/**
+ * struct drm_nouveau_vm_bind - structure for DRM_IOCTL_NOUVEAU_VM_BIND
+ */
+struct drm_nouveau_vm_bind {
+	/**
+	 * @op_count: the number of &drm_nouveau_vm_bind_op
+	 */
+	__u32 op_count;
+	/**
+	 * @flags: the flags for a &drm_nouveau_vm_bind ioctl
+	 */
+	__u32 flags;
+/**
+ * @DRM_NOUVEAU_VM_BIND_RUN_ASYNC:
+ *
+ * Indicates that the given VM_BIND operation should be executed asynchronously
+ * by the kernel.
+ *
+ * If this flag is not supplied the kernel executes the associated operations
+ * synchronously and doesn't accept any &drm_nouveau_sync objects.
+ */
+#define DRM_NOUVEAU_VM_BIND_RUN_ASYNC 0x1
+	/**
+	 * @wait_count: the number of wait &drm_nouveau_syncs
+	 */
+	__u32 wait_count;
+	/**
+	 * @sig_count: the number of &drm_nouveau_syncs to signal when finished
+	 */
+	__u32 sig_count;
+	/**
+	 * @wait_ptr: pointer to &drm_nouveau_syncs to wait for
+	 */
+	__u64 wait_ptr;
+	/**
+	 * @sig_ptr: pointer to &drm_nouveau_syncs to signal when finished
+	 */
+	__u64 sig_ptr;
+	/**
+	 * @op_ptr: pointer to the &drm_nouveau_vm_bind_ops to execute
+	 */
+	__u64 op_ptr;
+};
+
+/**
+ * struct drm_nouveau_exec_push - EXEC push operation
+ *
+ * This structure represents a single EXEC push operation. UMDs should pass an
+ * array of this structure via struct drm_nouveau_exec's &push_ptr field.
+ */
+struct drm_nouveau_exec_push {
+	/**
+	 * @va: the virtual address of the push buffer mapping
+	 */
+	__u64 va;
+	/**
+	 * @va_len: the length of the push buffer mapping
+	 */
+	__u64 va_len;
+};
+
+/**
+ * struct drm_nouveau_exec - structure for DRM_IOCTL_NOUVEAU_EXEC
+ */
+struct drm_nouveau_exec {
+	/**
+	 * @channel: the channel to execute the push buffer in
+	 */
+	__u32 channel;
+	/**
+	 * @push_count: the number of &drm_nouveau_exec_push ops
+	 */
+	__u32 push_count;
+	/**
+	 * @wait_count: the number of wait &drm_nouveau_syncs
+	 */
+	__u32 wait_count;
+	/**
+	 * @sig_count: the number of &drm_nouveau_syncs to signal when finished
+	 */
+	__u32 sig_count;
+	/**
+	 * @wait_ptr: pointer to &drm_nouveau_syncs to wait for
+	 */
+	__u64 wait_ptr;
+	/**
+	 * @sig_ptr: pointer to &drm_nouveau_syncs to signal when finished
+	 */
+	__u64 sig_ptr;
+	/**
+	 * @push_ptr: pointer to &drm_nouveau_exec_push ops
+	 */
+	__u64 push_ptr;
+};
+
 #define DRM_NOUVEAU_GETPARAM           0x00
 #define DRM_NOUVEAU_SETPARAM           0x01 /* deprecated */
 #define DRM_NOUVEAU_CHANNEL_ALLOC      0x02
@@ -174,6 +385,9 @@ struct drm_nouveau_gem_cpu_fini {
 #define DRM_NOUVEAU_NVIF               0x07
 #define DRM_NOUVEAU_SVM_INIT           0x08
 #define DRM_NOUVEAU_SVM_BIND           0x09
+#define DRM_NOUVEAU_VM_INIT            0x10
+#define DRM_NOUVEAU_VM_BIND            0x11
+#define DRM_NOUVEAU_EXEC               0x12
 #define DRM_NOUVEAU_GEM_NEW            0x40
 #define DRM_NOUVEAU_GEM_PUSHBUF        0x41
 #define DRM_NOUVEAU_GEM_CPU_PREP       0x42
@@ -239,6 +453,9 @@ struct drm_nouveau_svm_bind {
 #define DRM_IOCTL_NOUVEAU_GEM_CPU_FINI       DRM_IOW (DRM_COMMAND_BASE + DRM_NOUVEAU_GEM_CPU_FINI, struct drm_nouveau_gem_cpu_fini)
 #define DRM_IOCTL_NOUVEAU_GEM_INFO           DRM_IOWR(DRM_COMMAND_BASE + DRM_NOUVEAU_GEM_INFO, struct drm_nouveau_gem_info)
 
+#define DRM_IOCTL_NOUVEAU_VM_INIT            DRM_IOWR(DRM_COMMAND_BASE + DRM_NOUVEAU_VM_INIT, struct drm_nouveau_vm_init)
+#define DRM_IOCTL_NOUVEAU_VM_BIND            DRM_IOWR(DRM_COMMAND_BASE + DRM_NOUVEAU_VM_BIND, struct drm_nouveau_vm_bind)
+#define DRM_IOCTL_NOUVEAU_EXEC               DRM_IOWR(DRM_COMMAND_BASE + DRM_NOUVEAU_EXEC, struct drm_nouveau_exec)
 #if defined(__cplusplus)
 }
 #endif