ipc4: notification: make send_resource_notif() a syscall

Move user-facing notification functions
(send_copier_gateway_xrun_notif_msg, send_gateway_xrun_notif_msg,
send_mixer_underrun_notif_msg, send_process_data_error_notif_msg) to a
new notification-user.c file so they can run in userspace.

The send_resource_notif() function, which depends on the kernel-side
notification pool and IPC message infrastructure, is converted to a
Zephyr syscall. The implementation is renamed to
z_impl_send_resource_notif() and remains in notification.c alongside
is_notif_filtered_out() and ipc4_update_notification_mask().

The send_resource_notif() is converted to a system call only if
CONFIG_SOF_USERSPACE_LL=y, without it the behaviour is same as befofe.

A z_vrfy_send_resource_notif() handler is added to validate the
user-provided data buffer and other parameters before forwarding to
the kernel implementation.

Signed-off-by: Jyri Sarha <jyri.sarha@linux.intel.com>

Author: Jyri Sarha

src/include/ipc4/notification.h

@@ -297,4 +297,21 @@ void send_mixer_underrun_notif_msg(uint32_t resource_id, uint32_t eos_flag, uint
 				   uint32_t expected_data_mixed);
 void ipc4_update_notification_mask(uint32_t ntfy_mask, uint32_t enabled_mask);
 
+#ifdef CONFIG_SOF_USERSPACE_LL
+
+__syscall bool send_resource_notif(uint32_t resource_id, uint32_t event_type,
+				   uint32_t resource_type, void *data, uint32_t data_size);
+
+bool z_impl_send_resource_notif(uint32_t resource_id, uint32_t event_type,
+				uint32_t resource_type, void *data, uint32_t data_size);
+
+#include <zephyr/syscalls/notification.h>
+
+#else
+
+bool send_resource_notif(uint32_t resource_id, uint32_t event_type,
+			 uint32_t resource_type, void *data, uint32_t data_size);
+
+#endif /* CONFIG_SOF_USERSPACE_LL */
+
 #endif /* __IPC4_NOTIFICATION_H__ */

src/ipc/ipc4/CMakeLists.txt

@@ -7,6 +7,7 @@ add_local_sources(sof
 	helper.c
 	logging.c
 	notification.c
+	notification-user.c
 )
 
 # The DAI interface is not implemented in library builds and

src/ipc/ipc4/notification-user.c

@@ -0,0 +1,54 @@
+// SPDX-License-Identifier: BSD-3-Clause
+/*
+ * Copyright(c) 2023 Intel Corporation. All rights reserved.
+ *
+ * Author: Piotr Makaruk <piotr.makaruk@intel.com>
+ *	   Adrian Warecki <adrian.warecki@intel.com>
+ */
+
+#include <sof/common.h>
+#include <stdbool.h>
+#include <ipc4/notification.h>
+
+#include <rtos/symbol.h>
+
+static enum sof_ipc4_resource_event_type dir_to_xrun_event(enum sof_ipc_stream_direction dir)
+{
+	return (dir == SOF_IPC_STREAM_PLAYBACK) ? SOF_IPC4_GATEWAY_UNDERRUN_DETECTED :
+						  SOF_IPC4_GATEWAY_OVERRUN_DETECTED;
+}
+
+bool send_copier_gateway_xrun_notif_msg(uint32_t pipeline_id, enum sof_ipc_stream_direction dir)
+{
+	return send_resource_notif(pipeline_id, dir_to_xrun_event(dir), SOF_IPC4_PIPELINE, NULL,
+				   0);
+}
+
+bool send_gateway_xrun_notif_msg(uint32_t resource_id, enum sof_ipc_stream_direction dir)
+{
+	return send_resource_notif(resource_id, dir_to_xrun_event(dir), SOF_IPC4_GATEWAY, NULL, 0);
+}
+
+void send_mixer_underrun_notif_msg(uint32_t resource_id, uint32_t eos_flag, uint32_t data_mixed,
+				   uint32_t expected_data_mixed)
+{
+	struct ipc4_mixer_underrun_event_data mixer_underrun_data;
+
+	mixer_underrun_data.eos_flag = eos_flag;
+	mixer_underrun_data.data_mixed = data_mixed;
+	mixer_underrun_data.expected_data_mixed = expected_data_mixed;
+
+	send_resource_notif(resource_id, SOF_IPC4_MIXER_UNDERRUN_DETECTED, SOF_IPC4_PIPELINE,
+			    &mixer_underrun_data, sizeof(mixer_underrun_data));
+}
+EXPORT_SYMBOL(send_mixer_underrun_notif_msg);
+
+void send_process_data_error_notif_msg(uint32_t resource_id, uint32_t error_code)
+{
+	struct ipc4_process_data_error_event_data error_data;
+
+	error_data.error_code = error_code;
+
+	send_resource_notif(resource_id, SOF_IPC4_PROCESS_DATA_ERROR, SOF_IPC4_MODULE_INSTANCE,
+			    &error_data, sizeof(error_data));
+}

src/ipc/ipc4/notification.c

@@ -12,7 +12,9 @@
 #include <ipc4/notification.h>
 #include <sof/ipc/notification_pool.h>
 
-#include <rtos/symbol.h>
+#ifdef CONFIG_SOF_USERSPACE_LL
+#include <zephyr/internal/syscall_handler.h>
+#endif
 
 static uint32_t notification_mask = 0xFFFFFFFF;
 
@@ -37,8 +39,13 @@ static bool is_notif_filtered_out(uint32_t event_type)
 	return (notification_mask & BIT(notif_idx)) == 0;
 }
 
-static bool send_resource_notif(uint32_t resource_id, uint32_t event_type, uint32_t resource_type,
-				void *data, uint32_t data_size)
+#ifdef CONFIG_SOF_USERSPACE_LL
+bool z_impl_send_resource_notif(uint32_t resource_id, uint32_t event_type,
+				uint32_t resource_type, void *data, uint32_t data_size)
+#else
+bool send_resource_notif(uint32_t resource_id, uint32_t event_type,
+			 uint32_t resource_type, void *data, uint32_t data_size)
+#endif
 {
 	struct ipc_msg *msg;
 
@@ -80,49 +87,34 @@ static bool send_resource_notif(uint32_t resource_id, uint32_t event_type, uint3
 	return true;
 }
 
-static enum sof_ipc4_resource_event_type dir_to_xrun_event(enum sof_ipc_stream_direction dir)
-{
-	return (dir == SOF_IPC_STREAM_PLAYBACK) ? SOF_IPC4_GATEWAY_UNDERRUN_DETECTED :
-						  SOF_IPC4_GATEWAY_OVERRUN_DETECTED;
-}
-
 void ipc4_update_notification_mask(uint32_t ntfy_mask, uint32_t enabled_mask)
 {
 	notification_mask &= enabled_mask | (~ntfy_mask);
 	notification_mask |= enabled_mask & ntfy_mask;
 }
 
-bool send_copier_gateway_xrun_notif_msg(uint32_t pipeline_id, enum sof_ipc_stream_direction dir)
+#ifdef CONFIG_SOF_USERSPACE_LL
+static inline bool z_vrfy_send_resource_notif(uint32_t resource_id, uint32_t event_type,
+					      uint32_t resource_type, void *data,
+					      uint32_t data_size)
 {
-	return send_resource_notif(pipeline_id, dir_to_xrun_event(dir), SOF_IPC4_PIPELINE, NULL,
-				   0);
-}
+	/* Validate event_type is a known resource event */
+	K_OOPS(K_SYSCALL_VERIFY(event_type < SOF_IPC4_INVALID_RESOURCE_EVENT_TYPE));
 
-bool send_gateway_xrun_notif_msg(uint32_t resource_id, enum sof_ipc_stream_direction dir)
-{
-	return send_resource_notif(resource_id, dir_to_xrun_event(dir), SOF_IPC4_GATEWAY, NULL, 0);
-}
+	/* Validate resource_type is a known resource type */
+	K_OOPS(K_SYSCALL_VERIFY(resource_type < SOF_IPC4_INVALID_RESOURCE_TYPE));
 
-void send_mixer_underrun_notif_msg(uint32_t resource_id, uint32_t eos_flag, uint32_t data_mixed,
-				   uint32_t expected_data_mixed)
-{
-	struct ipc4_mixer_underrun_event_data mixer_underrun_data;
-
-	mixer_underrun_data.eos_flag = eos_flag;
-	mixer_underrun_data.data_mixed = data_mixed;
-	mixer_underrun_data.expected_data_mixed = expected_data_mixed;
+	/* data and data_size must be consistent */
+	K_OOPS(K_SYSCALL_VERIFY((!data && !data_size) || (data && data_size)));
 
-	send_resource_notif(resource_id, SOF_IPC4_MIXER_UNDERRUN_DETECTED, SOF_IPC4_PIPELINE,
-			    &mixer_underrun_data, sizeof(mixer_underrun_data));
-}
-EXPORT_SYMBOL(send_mixer_underrun_notif_msg);
-
-void send_process_data_error_notif_msg(uint32_t resource_id, uint32_t error_code)
-{
-	struct ipc4_process_data_error_event_data error_data;
+	/* Payload must fit in the event_data union and the IPC message */
+	K_OOPS(K_SYSCALL_VERIFY(data_size <= sizeof(union ipc4_resource_event_data)));
+	K_OOPS(K_SYSCALL_VERIFY(data_size <= SOF_IPC_MSG_MAX_SIZE));
 
-	error_data.error_code = error_code;
+	if (data && data_size)
+		K_OOPS(K_SYSCALL_MEMORY_READ(data, data_size));
 
-	send_resource_notif(resource_id, SOF_IPC4_PROCESS_DATA_ERROR, SOF_IPC4_MODULE_INSTANCE,
-			    &error_data, sizeof(error_data));
+	return z_impl_send_resource_notif(resource_id, event_type, resource_type, data, data_size);
 }
+#include <zephyr/syscalls/send_resource_notif_mrsh.c>
+#endif

zephyr/CMakeLists.txt

@@ -634,6 +634,8 @@ zephyr_library_sources_ifdef(CONFIG_USERSPACE syscall/dai.c)
 
 zephyr_syscall_header(${SOF_SRC_PATH}/include/user/debug_stream_slot.h)
 
+zephyr_syscall_header(${SOF_SRC_PATH}/include/ipc4/notification.h)
+
 zephyr_library_link_libraries(SOF)
 target_link_libraries(SOF INTERFACE zephyr_interface)