drm/amdkfd: Add ioctls for GPUVM memory management

v2:
* Fix error handling after kfd_bind_process_to_device in
  kfd_ioctl_map_memory_to_gpu
v3:
* Add ioctl to acquire VM from a DRM FD
v4:
* Return number of successful map/unmap operations in failure cases
* Facilitate partial retry after failed map/unmap
* Added comments with parameter descriptions to new APIs
* Defined AMDKFD_IOC_FREE_MEMORY_OF_GPU write-only

Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>

1 files changed, 96 insertions, 1 deletions

diff --git a/include/uapi/linux/kfd_ioctl.h b/include/uapi/linux/kfd_ioctl.h
index 52014370e2e5..b4f5073dbac2 100644
--- a/include/uapi/linux/kfd_ioctl.h
+++ b/include/uapi/linux/kfd_ioctl.h
@@ -286,6 +286,86 @@ struct kfd_ioctl_set_trap_handler_args {
 	__u32 pad;
 };
 
+struct kfd_ioctl_acquire_vm_args {
+	__u32 drm_fd;	/* to KFD */
+	__u32 gpu_id;	/* to KFD */
+};
+
+/* Allocation flags: memory types */
+#define KFD_IOC_ALLOC_MEM_FLAGS_VRAM		(1 << 0)
+#define KFD_IOC_ALLOC_MEM_FLAGS_GTT		(1 << 1)
+#define KFD_IOC_ALLOC_MEM_FLAGS_USERPTR		(1 << 2)
+#define KFD_IOC_ALLOC_MEM_FLAGS_DOORBELL	(1 << 3)
+/* Allocation flags: attributes/access options */
+#define KFD_IOC_ALLOC_MEM_FLAGS_WRITABLE	(1 << 31)
+#define KFD_IOC_ALLOC_MEM_FLAGS_EXECUTABLE	(1 << 30)
+#define KFD_IOC_ALLOC_MEM_FLAGS_PUBLIC		(1 << 29)
+#define KFD_IOC_ALLOC_MEM_FLAGS_NO_SUBSTITUTE	(1 << 28)
+#define KFD_IOC_ALLOC_MEM_FLAGS_AQL_QUEUE_MEM	(1 << 27)
+#define KFD_IOC_ALLOC_MEM_FLAGS_COHERENT	(1 << 26)
+
+/* Allocate memory for later SVM (shared virtual memory) mapping.
+ *
+ * @va_addr:     virtual address of the memory to be allocated
+ *               all later mappings on all GPUs will use this address
+ * @size:        size in bytes
+ * @handle:      buffer handle returned to user mode, used to refer to
+ *               this allocation for mapping, unmapping and freeing
+ * @mmap_offset: for CPU-mapping the allocation by mmapping a render node
+ *               for userptrs this is overloaded to specify the CPU address
+ * @gpu_id:      device identifier
+ * @flags:       memory type and attributes. See KFD_IOC_ALLOC_MEM_FLAGS above
+ */
+struct kfd_ioctl_alloc_memory_of_gpu_args {
+	__u64 va_addr;		/* to KFD */
+	__u64 size;		/* to KFD */
+	__u64 handle;		/* from KFD */
+	__u64 mmap_offset;	/* to KFD (userptr), from KFD (mmap offset) */
+	__u32 gpu_id;		/* to KFD */
+	__u32 flags;
+};
+
+/* Free memory allocated with kfd_ioctl_alloc_memory_of_gpu
+ *
+ * @handle: memory handle returned by alloc
+ */
+struct kfd_ioctl_free_memory_of_gpu_args {
+	__u64 handle;		/* to KFD */
+};
+
+/* Map memory to one or more GPUs
+ *
+ * @handle:                memory handle returned by alloc
+ * @device_ids_array_ptr:  array of gpu_ids (__u32 per device)
+ * @n_devices:             number of devices in the array
+ * @n_success:             number of devices mapped successfully
+ *
+ * @n_success returns information to the caller how many devices from
+ * the start of the array have mapped the buffer successfully. It can
+ * be passed into a subsequent retry call to skip those devices. For
+ * the first call the caller should initialize it to 0.
+ *
+ * If the ioctl completes with return code 0 (success), n_success ==
+ * n_devices.
+ */
+struct kfd_ioctl_map_memory_to_gpu_args {
+	__u64 handle;			/* to KFD */
+	__u64 device_ids_array_ptr;	/* to KFD */
+	__u32 n_devices;		/* to KFD */
+	__u32 n_success;		/* to/from KFD */
+};
+
+/* Unmap memory from one or more GPUs
+ *
+ * same arguments as for mapping
+ */
+struct kfd_ioctl_unmap_memory_from_gpu_args {
+	__u64 handle;			/* to KFD */
+	__u64 device_ids_array_ptr;	/* to KFD */
+	__u32 n_devices;		/* to KFD */
+	__u32 n_success;		/* to/from KFD */
+};
+
 #define AMDKFD_IOCTL_BASE 'K'
 #define AMDKFD_IO(nr)			_IO(AMDKFD_IOCTL_BASE, nr)
 #define AMDKFD_IOR(nr, type)		_IOR(AMDKFD_IOCTL_BASE, nr, type)
@@ -353,7 +433,22 @@ struct kfd_ioctl_set_trap_handler_args {
 		AMDKFD_IOWR(0x14,		\
 			struct kfd_ioctl_get_process_apertures_new_args)
 
+#define AMDKFD_IOC_ACQUIRE_VM			\
+		AMDKFD_IOW(0x15, struct kfd_ioctl_acquire_vm_args)
+
+#define AMDKFD_IOC_ALLOC_MEMORY_OF_GPU		\
+		AMDKFD_IOWR(0x16, struct kfd_ioctl_alloc_memory_of_gpu_args)
+
+#define AMDKFD_IOC_FREE_MEMORY_OF_GPU		\
+		AMDKFD_IOW(0x17, struct kfd_ioctl_free_memory_of_gpu_args)
+
+#define AMDKFD_IOC_MAP_MEMORY_TO_GPU		\
+		AMDKFD_IOWR(0x18, struct kfd_ioctl_map_memory_to_gpu_args)
+
+#define AMDKFD_IOC_UNMAP_MEMORY_FROM_GPU	\
+		AMDKFD_IOWR(0x19, struct kfd_ioctl_unmap_memory_from_gpu_args)
+
 #define AMDKFD_COMMAND_START		0x01
-#define AMDKFD_COMMAND_END		0x15
+#define AMDKFD_COMMAND_END		0x1A
 
 #endif