Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) // SPDX-License-Identifier: GPL-2.0-only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) #include <linux/sched.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3) #include <linux/ftrace.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4) #include <asm/ptrace.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5) #include <asm/bitops.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6) #include <asm/stacktrace.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7) #include <asm/unwind.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9) unsigned long unwind_get_return_address(struct unwind_state *state)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) 	unsigned long addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) 	if (unwind_done(state))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) 	addr = READ_ONCE_NOCHECK(*state->sp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) 	return ftrace_graph_ret_addr(state->task, &state->graph_idx,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) 				     addr, state->sp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) EXPORT_SYMBOL_GPL(unwind_get_return_address);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) unsigned long *unwind_get_return_address_ptr(struct unwind_state *state)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) 	return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) bool unwind_next_frame(struct unwind_state *state)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) 	struct stack_info *info = &state->stack_info;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) 	if (unwind_done(state))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) 		return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) 	do {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) 		for (state->sp++; state->sp < info->end; state->sp++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 			unsigned long addr = READ_ONCE_NOCHECK(*state->sp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 			if (__kernel_text_address(addr))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) 				return true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) 		state->sp = PTR_ALIGN(info->next_sp, sizeof(long));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) 	} while (!get_stack_info(state->sp, state->task, info,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) 				 &state->stack_mask));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) 	return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) EXPORT_SYMBOL_GPL(unwind_next_frame);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) void __unwind_start(struct unwind_state *state, struct task_struct *task,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) 		    struct pt_regs *regs, unsigned long *first_frame)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) 	memset(state, 0, sizeof(*state));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) 	state->task = task;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) 	state->sp   = PTR_ALIGN(first_frame, sizeof(long));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) 	get_stack_info(first_frame, state->task, &state->stack_info,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) 		       &state->stack_mask);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) 	 * The caller can provide the address of the first frame directly
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) 	 * (first_frame) or indirectly (regs->sp) to indicate which stack frame
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) 	 * to start unwinding at.  Skip ahead until we reach it.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) 	if (!unwind_done(state) &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) 	    (!on_stack(&state->stack_info, first_frame, sizeof(long)) ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) 	    !__kernel_text_address(*first_frame)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) 		unwind_next_frame(state);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) EXPORT_SYMBOL_GPL(__unwind_start);