xref: /linux/arch/s390/include/asm/ptrace.h (revision 6f7e6393d1ce636bb7ec77a7fe7b77458fddf701)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  *  S390 version
4  *    Copyright IBM Corp. 1999, 2000
5  *    Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com)
6  */
7 #ifndef _S390_PTRACE_H
8 #define _S390_PTRACE_H
9 
10 #include <linux/bits.h>
11 #include <linux/typecheck.h>
12 #include <uapi/asm/ptrace.h>
13 #include <asm/thread_info.h>
14 #include <asm/tpi.h>
15 
16 #define PIF_SYSCALL			0	/* inside a system call */
17 #define PIF_PSW_ADDR_ADJUSTED		1	/* psw address has been adjusted */
18 #define PIF_SYSCALL_RET_SET		2	/* return value was set via ptrace */
19 #define PIF_GUEST_FAULT			3	/* indicates program check in sie64a */
20 #define PIF_FTRACE_FULL_REGS		4	/* all register contents valid (ftrace) */
21 
22 #define _PIF_SYSCALL			BIT(PIF_SYSCALL)
23 #define _PIF_ADDR_PSW_ADJUSTED		BIT(PIF_PSW_ADDR_ADJUSTED)
24 #define _PIF_SYSCALL_RET_SET		BIT(PIF_SYSCALL_RET_SET)
25 #define _PIF_GUEST_FAULT		BIT(PIF_GUEST_FAULT)
26 #define _PIF_FTRACE_FULL_REGS		BIT(PIF_FTRACE_FULL_REGS)
27 
28 #define PSW32_MASK_PER		_AC(0x40000000, UL)
29 #define PSW32_MASK_DAT		_AC(0x04000000, UL)
30 #define PSW32_MASK_IO		_AC(0x02000000, UL)
31 #define PSW32_MASK_EXT		_AC(0x01000000, UL)
32 #define PSW32_MASK_KEY		_AC(0x00F00000, UL)
33 #define PSW32_MASK_BASE		_AC(0x00080000, UL)	/* Always one */
34 #define PSW32_MASK_MCHECK	_AC(0x00040000, UL)
35 #define PSW32_MASK_WAIT		_AC(0x00020000, UL)
36 #define PSW32_MASK_PSTATE	_AC(0x00010000, UL)
37 #define PSW32_MASK_ASC		_AC(0x0000C000, UL)
38 #define PSW32_MASK_CC		_AC(0x00003000, UL)
39 #define PSW32_MASK_PM		_AC(0x00000f00, UL)
40 #define PSW32_MASK_RI		_AC(0x00000080, UL)
41 
42 #define PSW32_ADDR_AMODE	_AC(0x80000000, UL)
43 #define PSW32_ADDR_INSN		_AC(0x7FFFFFFF, UL)
44 
45 #define PSW32_DEFAULT_KEY	((PAGE_DEFAULT_ACC) << 20)
46 
47 #define PSW32_ASC_PRIMARY	_AC(0x00000000, UL)
48 #define PSW32_ASC_ACCREG	_AC(0x00004000, UL)
49 #define PSW32_ASC_SECONDARY	_AC(0x00008000, UL)
50 #define PSW32_ASC_HOME		_AC(0x0000C000, UL)
51 
52 #define PSW_DEFAULT_KEY			((PAGE_DEFAULT_ACC) << 52)
53 
54 #define PSW_KERNEL_BITS	(PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_ASC_HOME | \
55 			 PSW_MASK_EA | PSW_MASK_BA | PSW_MASK_DAT)
56 #define PSW_USER_BITS	(PSW_MASK_DAT | PSW_MASK_IO | PSW_MASK_EXT | \
57 			 PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_MASK_MCHECK | \
58 			 PSW_MASK_PSTATE | PSW_ASC_PRIMARY)
59 
60 #ifndef __ASSEMBLER__
61 
62 struct psw_bits {
63 	unsigned long	     :	1;
64 	unsigned long per    :	1; /* PER-Mask */
65 	unsigned long	     :	3;
66 	unsigned long dat    :	1; /* DAT Mode */
67 	unsigned long io     :	1; /* Input/Output Mask */
68 	unsigned long ext    :	1; /* External Mask */
69 	unsigned long key    :	4; /* PSW Key */
70 	unsigned long	     :	1;
71 	unsigned long mcheck :	1; /* Machine-Check Mask */
72 	unsigned long wait   :	1; /* Wait State */
73 	unsigned long pstate :	1; /* Problem State */
74 	unsigned long as     :	2; /* Address Space Control */
75 	unsigned long cc     :	2; /* Condition Code */
76 	unsigned long pm     :	4; /* Program Mask */
77 	unsigned long ri     :	1; /* Runtime Instrumentation */
78 	unsigned long	     :	6;
79 	unsigned long eaba   :	2; /* Addressing Mode */
80 	unsigned long	     : 31;
81 	unsigned long ia     : 64; /* Instruction Address */
82 };
83 
84 enum {
85 	PSW_BITS_AMODE_24BIT = 0,
86 	PSW_BITS_AMODE_31BIT = 1,
87 	PSW_BITS_AMODE_64BIT = 3
88 };
89 
90 enum {
91 	PSW_BITS_AS_PRIMARY	= 0,
92 	PSW_BITS_AS_ACCREG	= 1,
93 	PSW_BITS_AS_SECONDARY	= 2,
94 	PSW_BITS_AS_HOME	= 3
95 };
96 
97 #define psw_bits(__psw) (*({			\
98 	typecheck(psw_t, __psw);		\
99 	&(*(struct psw_bits *)(&(__psw)));	\
100 }))
101 
102 typedef struct {
103 	unsigned int mask;
104 	unsigned int addr;
105 } psw32_t __aligned(8);
106 
107 #define PGM_INT_CODE_MASK	0x7f
108 #define PGM_INT_CODE_PER	0x80
109 
110 /*
111  * The pt_regs struct defines the way the registers are stored on
112  * the stack during a system call.
113  */
114 struct pt_regs {
115 	union {
116 		user_pt_regs user_regs;
117 		struct {
118 			unsigned long args[1];
119 			psw_t psw;
120 			unsigned long gprs[NUM_GPRS];
121 		};
122 	};
123 	union {
124 		unsigned long orig_gpr2;
125 		unsigned long monitor_code;
126 	};
127 	union {
128 		struct {
129 			unsigned int int_code;
130 			unsigned int int_parm;
131 			unsigned long int_parm_long;
132 		};
133 		struct tpi_info tpi_info;
134 	};
135 	unsigned long flags;
136 	unsigned long last_break;
137 };
138 
139 /*
140  * Program event recording (PER) register set.
141  */
142 struct per_regs {
143 	unsigned long control;		/* PER control bits */
144 	unsigned long start;		/* PER starting address */
145 	unsigned long end;		/* PER ending address */
146 };
147 
148 /*
149  * PER event contains information about the cause of the last PER exception.
150  */
151 struct per_event {
152 	unsigned short cause;		/* PER code, ATMID and AI */
153 	unsigned long address;		/* PER address */
154 	unsigned char paid;		/* PER access identification */
155 };
156 
157 /*
158  * Simplified per_info structure used to decode the ptrace user space ABI.
159  */
160 struct per_struct_kernel {
161 	unsigned long cr9;		/* PER control bits */
162 	unsigned long cr10;		/* PER starting address */
163 	unsigned long cr11;		/* PER ending address */
164 	unsigned long bits;		/* Obsolete software bits */
165 	unsigned long starting_addr;	/* User specified start address */
166 	unsigned long ending_addr;	/* User specified end address */
167 	unsigned short perc_atmid;	/* PER trap ATMID */
168 	unsigned long address;		/* PER trap instruction address */
169 	unsigned char access_id;	/* PER trap access identification */
170 };
171 
172 #define PER_EVENT_MASK			0xEB000000UL
173 
174 #define PER_EVENT_BRANCH		0x80000000UL
175 #define PER_EVENT_IFETCH		0x40000000UL
176 #define PER_EVENT_STORE			0x20000000UL
177 #define PER_EVENT_STORE_REAL		0x08000000UL
178 #define PER_EVENT_TRANSACTION_END	0x02000000UL
179 #define PER_EVENT_NULLIFICATION		0x01000000UL
180 
181 #define PER_CONTROL_MASK		0x00e00000UL
182 
183 #define PER_CONTROL_BRANCH_ADDRESS	0x00800000UL
184 #define PER_CONTROL_SUSPENSION		0x00400000UL
185 #define PER_CONTROL_ALTERATION		0x00200000UL
186 
187 static inline void set_pt_regs_flag(struct pt_regs *regs, int flag)
188 {
189 	regs->flags |= (1UL << flag);
190 }
191 
192 static inline void clear_pt_regs_flag(struct pt_regs *regs, int flag)
193 {
194 	regs->flags &= ~(1UL << flag);
195 }
196 
197 static inline int test_pt_regs_flag(struct pt_regs *regs, int flag)
198 {
199 	return !!(regs->flags & (1UL << flag));
200 }
201 
202 static inline int test_and_clear_pt_regs_flag(struct pt_regs *regs, int flag)
203 {
204 	int ret = test_pt_regs_flag(regs, flag);
205 
206 	clear_pt_regs_flag(regs, flag);
207 	return ret;
208 }
209 
210 struct task_struct;
211 
212 void update_cr_regs(struct task_struct *task);
213 
214 /*
215  * These are defined as per linux/ptrace.h, which see.
216  */
217 #define arch_has_single_step()	(1)
218 #define arch_has_block_step()	(1)
219 
220 #define profile_pc(regs) instruction_pointer(regs)
221 
222 static __always_inline bool user_mode(const struct pt_regs *regs)
223 {
224 	return psw_bits(regs->psw).pstate;
225 }
226 
227 static inline long regs_return_value(const struct pt_regs *regs)
228 {
229 	return regs->gprs[2];
230 }
231 
232 static __always_inline unsigned long instruction_pointer(const struct pt_regs *regs)
233 {
234 	return regs->psw.addr;
235 }
236 
237 static inline void instruction_pointer_set(struct pt_regs *regs,
238 					   unsigned long val)
239 {
240 	regs->psw.addr = val;
241 }
242 
243 int regs_query_register_offset(const char *name);
244 const char *regs_query_register_name(unsigned int offset);
245 
246 static __always_inline unsigned long kernel_stack_pointer(const struct pt_regs *regs)
247 {
248 	return regs->gprs[15];
249 }
250 
251 static __always_inline unsigned long user_stack_pointer(const struct pt_regs *regs)
252 {
253 	return regs->gprs[15];
254 }
255 
256 static __always_inline unsigned long regs_get_register(const struct pt_regs *regs,
257 						       unsigned int offset)
258 {
259 	if (offset >= NUM_GPRS)
260 		return 0;
261 	return regs->gprs[offset];
262 }
263 
264 static __always_inline int regs_within_kernel_stack(const struct pt_regs *regs,
265 						    unsigned long addr)
266 {
267 	unsigned long ksp = kernel_stack_pointer(regs);
268 
269 	return (addr & ~(THREAD_SIZE - 1)) == (ksp & ~(THREAD_SIZE - 1));
270 }
271 
272 /**
273  * regs_get_kernel_stack_nth() - get Nth entry of the stack
274  * @regs:pt_regs which contains kernel stack pointer.
275  * @n:stack entry number.
276  *
277  * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
278  * is specifined by @regs. If the @n th entry is NOT in the kernel stack,
279  * this returns 0.
280  */
281 static __always_inline unsigned long regs_get_kernel_stack_nth(const struct pt_regs *regs,
282 							       unsigned int n)
283 {
284 	unsigned long addr;
285 
286 	addr = kernel_stack_pointer(regs) + n * sizeof(long);
287 	if (!regs_within_kernel_stack(regs, addr))
288 		return 0;
289 	return READ_ONCE_NOCHECK(*(unsigned long *)addr);
290 }
291 
292 /**
293  * regs_get_kernel_argument() - get Nth function argument in kernel
294  * @regs:	pt_regs of that context
295  * @n:		function argument number (start from 0)
296  *
297  * regs_get_kernel_argument() returns @n th argument of the function call.
298  */
299 static __always_inline unsigned long regs_get_kernel_argument(const struct pt_regs *regs,
300 							      unsigned int n)
301 {
302 	unsigned int argoffset = STACK_FRAME_OVERHEAD / sizeof(long);
303 
304 #define NR_REG_ARGUMENTS 5
305 	if (n < NR_REG_ARGUMENTS)
306 		return regs_get_register(regs, 2 + n);
307 	n -= NR_REG_ARGUMENTS;
308 	return regs_get_kernel_stack_nth(regs, argoffset + n);
309 }
310 
311 static __always_inline void regs_set_return_value(struct pt_regs *regs, unsigned long rc)
312 {
313 	regs->gprs[2] = rc;
314 }
315 
316 #endif /* __ASSEMBLER__ */
317 #endif /* _S390_PTRACE_H */
318