1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 #ifndef _POWERPC_PERF_CALLCHAIN_H 3 #define _POWERPC_PERF_CALLCHAIN_H 4 5 int read_user_stack_slow(const void __user *ptr, void *buf, int nb); 6 void perf_callchain_user_64(struct perf_callchain_entry_ctx *entry, 7 struct pt_regs *regs); 8 void perf_callchain_user_32(struct perf_callchain_entry_ctx *entry, 9 struct pt_regs *regs); 10 11 static inline bool invalid_user_sp(unsigned long sp) 12 { 13 unsigned long mask = is_32bit_task() ? 3 : 7; 14 unsigned long top = STACK_TOP - (is_32bit_task() ? 16 : 32); 15 16 return (!sp || (sp & mask) || (sp > top)); 17 } 18 19 /* 20 * On 32-bit we just access the address and let hash_page create a 21 * HPTE if necessary, so there is no need to fall back to reading 22 * the page tables. Since this is called at interrupt level, 23 * do_page_fault() won't treat a DSI as a page fault. 24 */ 25 static inline int __read_user_stack(const void __user *ptr, void *ret, 26 size_t size) 27 { 28 unsigned long addr = (unsigned long)ptr; 29 int rc; 30 31 if (addr > TASK_SIZE - size || (addr & (size - 1))) 32 return -EFAULT; 33 34 rc = copy_from_user_nofault(ret, ptr, size); 35 36 if (IS_ENABLED(CONFIG_PPC64) && rc) 37 return read_user_stack_slow(ptr, ret, size); 38 39 return rc; 40 } 41 42 #endif /* _POWERPC_PERF_CALLCHAIN_H */ 43