1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2019 Ian Lepore <ian@freebsd.org> 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include <sys/cdefs.h> 29 __FBSDID("$FreeBSD$"); 30 31 #include <sys/types.h> 32 #include <sys/systm.h> 33 #include <sys/lock.h> 34 #include <sys/mutex.h> 35 #include <sys/proc.h> 36 #include <sys/stack.h> 37 38 #include <machine/pcb.h> 39 #include <machine/stack.h> 40 41 static void 42 stack_capture(struct stack *st, struct unwind_state *state) 43 { 44 45 stack_zero(st); 46 while (unwind_stack_one(state, 0) == 0) { 47 if (stack_put(st, state->registers[PC]) == -1) 48 break; 49 } 50 } 51 52 void 53 stack_save(struct stack *st) 54 { 55 struct unwind_state state; 56 uint32_t sp; 57 58 /* Read the stack pointer */ 59 __asm __volatile("mov %0, sp" : "=&r" (sp)); 60 61 state.registers[FP] = (uint32_t)__builtin_frame_address(0); 62 state.registers[SP] = sp; 63 state.registers[LR] = (uint32_t)__builtin_return_address(0); 64 state.registers[PC] = (uint32_t)stack_save; 65 66 stack_capture(st, &state); 67 } 68 69 int 70 stack_save_td(struct stack *st, struct thread *td) 71 { 72 struct unwind_state state; 73 74 THREAD_LOCK_ASSERT(td, MA_OWNED); 75 KASSERT(!TD_IS_SWAPPED(td), 76 ("stack_save_td: thread %p is swapped", td)); 77 78 if (TD_IS_RUNNING(td)) 79 return (EOPNOTSUPP); 80 81 state.registers[FP] = td->td_pcb->pcb_regs.sf_r11; 82 state.registers[SP] = td->td_pcb->pcb_regs.sf_sp; 83 state.registers[LR] = td->td_pcb->pcb_regs.sf_lr; 84 state.registers[PC] = td->td_pcb->pcb_regs.sf_pc; 85 86 stack_capture(st, &state); 87 return (0); 88 } 89