[PATCH drm-next v2 07/16] drm/nouveau: new VM_BIND uapi interfaces

From: Danilo Krummrich <dakr@redhat.com>
To: airlied@gmail.com, daniel@ffwll.ch, tzimmermann@suse.de,
	mripard@kernel.org, corbet@lwn.net, christian.koenig@amd.com,
	bskeggs@redhat.com, Liam.Howlett@oracle.com,
	matthew.brost@intel.com, boris.brezillon@collabora.com,
	alexdeucher@gmail.com, ogabbay@kernel.org, bagasdotme@gmail.com,
	willy@infradead.org, jason@jlekstrand.net
Cc: dri-devel@lists.freedesktop.org, nouveau@lists.freedesktop.org,
	linux-doc@vger.kernel.org, linux-mm@kvack.org,
	linux-kernel@vger.kernel.org, Danilo Krummrich <dakr@redhat.com>,
	Dave Airlie <airlied@redhat.com>
Subject: [PATCH drm-next v2 07/16] drm/nouveau: new VM_BIND uapi interfaces
Date: Fri, 17 Feb 2023 14:48:11 +0100	[thread overview]
Message-ID: <20230217134820.14672-2-dakr@redhat.com> (raw)
In-Reply-To: <20230217134422.14116-1-dakr@redhat.com>

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.

Co-authored-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Danilo Krummrich <dakr@redhat.com>
---
 Documentation/gpu/driver-uapi.rst |   8 ++
 include/uapi/drm/nouveau_drm.h    | 220 ++++++++++++++++++++++++++++++
 2 files changed, 228 insertions(+)

diff --git a/Documentation/gpu/driver-uapi.rst b/Documentation/gpu/driver-uapi.rst
index 4411e6919a3d..9c7ca6e33a68 100644
--- a/Documentation/gpu/driver-uapi.rst
+++ b/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
diff --git a/include/uapi/drm/nouveau_drm.h b/include/uapi/drm/nouveau_drm.h
index 853a327433d3..dbe0afbd858a 100644
--- a/include/uapi/drm/nouveau_drm.h
+++ b/include/uapi/drm/nouveau_drm.h
@@ -126,6 +126,220 @@ 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.
+ */
+struct drm_nouveau_vm_init {
+	/**
+	 * @unmanaged_addr: start address of the kernel managed VA space region
+	 */
+	__u64 unmanaged_addr;
+	/**
+	 * @unmanaged_size: size of the kernel managed VA space region in bytes
+	 */
+	__u64 unmanaged_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_ALLOC:
+ *
+ * The alloc operation is used to reserve a VA space region within 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 region.
+ */
+#define DRM_NOUVEAU_VM_BIND_OP_ALLOC 0x0
+/**
+ * @DRM_NOUVEAU_VM_BIND_OP_FREE: Free a reserved VA space region.
+ */
+#define DRM_NOUVEAU_VM_BIND_OP_FREE 0x1
+/**
+ * @DRM_NOUVEAU_VM_BIND_OP_MAP:
+ *
+ * Map a GEM object to the GPU's VA space. The mapping must be fully enclosed by
+ * a previously allocated VA space region. If the region is sparse, existing
+ * sparse mappings are overwritten.
+ */
+#define DRM_NOUVEAU_VM_BIND_OP_MAP 0x2
+/**
+ * @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.
+ */
+#define DRM_NOUVEAU_VM_BIND_OP_UNMAP 0x3
+	/**
+	 * @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 /* deprecated */
 #define DRM_NOUVEAU_SETPARAM           0x01 /* deprecated */
 #define DRM_NOUVEAU_CHANNEL_ALLOC      0x02 /* deprecated */
@@ -136,6 +350,9 @@ 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
@@ -197,6 +414,9 @@ 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
-- 
2.39.1

