1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/compat.h> 3 #include <linux/errno.h> 4 #include <linux/kernel.h> 5 #include <linux/perf_event.h> 6 #include <linux/bug.h> 7 #include <linux/sched/task_stack.h> 8 9 #include <asm/perf_regs.h> 10 #include <asm/ptrace.h> 11 12 u64 perf_reg_value(struct pt_regs *regs, int idx) 13 { 14 if (WARN_ON_ONCE((u32)idx >= PERF_REG_ARM64_MAX)) 15 return 0; 16 17 /* 18 * Compat (i.e. 32 bit) mode: 19 * - PC has been set in the pt_regs struct in kernel_entry, 20 * - Handle SP and LR here. 21 */ 22 if (compat_user_mode(regs)) { 23 if ((u32)idx == PERF_REG_ARM64_SP) 24 return regs->compat_sp; 25 if ((u32)idx == PERF_REG_ARM64_LR) 26 return regs->compat_lr; 27 } 28 29 if ((u32)idx == PERF_REG_ARM64_SP) 30 return regs->sp; 31 32 if ((u32)idx == PERF_REG_ARM64_PC) 33 return regs->pc; 34 35 return regs->regs[idx]; 36 } 37 38 #define REG_RESERVED (~((1ULL << PERF_REG_ARM64_MAX) - 1)) 39 40 int perf_reg_validate(u64 mask) 41 { 42 if (!mask || mask & REG_RESERVED) 43 return -EINVAL; 44 45 return 0; 46 } 47 48 u64 perf_reg_abi(struct task_struct *task) 49 { 50 if (is_compat_thread(task_thread_info(task))) 51 return PERF_SAMPLE_REGS_ABI_32; 52 else 53 return PERF_SAMPLE_REGS_ABI_64; 54 } 55 56 void perf_get_regs_user(struct perf_regs *regs_user, 57 struct pt_regs *regs, 58 struct pt_regs *regs_user_copy) 59 { 60 regs_user->regs = task_pt_regs(current); 61 regs_user->abi = perf_reg_abi(current); 62 } 63