1// SPDX-License-Identifier: GPL-2.0
2/*
3 *  Ptrace user space interface.
4 *
5 *    Copyright IBM Corp. 1999, 2010
6 *    Author(s): Denis Joseph Barrow
7 *               Martin Schwidefsky (schwidefsky@de.ibm.com)
8 */
9
10#include "asm/ptrace.h"
11#include <linux/kernel.h>
12#include <linux/sched.h>
13#include <linux/sched/task_stack.h>
14#include <linux/mm.h>
15#include <linux/smp.h>
16#include <linux/errno.h>
17#include <linux/ptrace.h>
18#include <linux/user.h>
19#include <linux/security.h>
20#include <linux/audit.h>
21#include <linux/signal.h>
22#include <linux/elf.h>
23#include <linux/regset.h>
24#include <linux/seccomp.h>
25#include <linux/compat.h>
26#include <trace/syscall.h>
27#include <asm/guarded_storage.h>
28#include <asm/access-regs.h>
29#include <asm/page.h>
30#include <linux/uaccess.h>
31#include <asm/unistd.h>
32#include <asm/runtime_instr.h>
33#include <asm/facility.h>
34#include <asm/fpu.h>
35
36#include "entry.h"
37
38#ifdef CONFIG_COMPAT
39#include "compat_ptrace.h"
40#endif
41
42void update_cr_regs(struct task_struct *task)
43{
44	struct pt_regs *regs = task_pt_regs(task);
45	struct thread_struct *thread = &task->thread;
46	union ctlreg0 cr0_old, cr0_new;
47	union ctlreg2 cr2_old, cr2_new;
48	int cr0_changed, cr2_changed;
49	union {
50		struct ctlreg regs[3];
51		struct {
52			struct ctlreg control;
53			struct ctlreg start;
54			struct ctlreg end;
55		};
56	} old, new;
57
58	local_ctl_store(0, &cr0_old.reg);
59	local_ctl_store(2, &cr2_old.reg);
60	cr0_new = cr0_old;
61	cr2_new = cr2_old;
62	/* Take care of the enable/disable of transactional execution. */
63	if (MACHINE_HAS_TE) {
64		/* Set or clear transaction execution TXC bit 8. */
65		cr0_new.tcx = 1;
66		if (task->thread.per_flags & PER_FLAG_NO_TE)
67			cr0_new.tcx = 0;
68		/* Set or clear transaction execution TDC bits 62 and 63. */
69		cr2_new.tdc = 0;
70		if (task->thread.per_flags & PER_FLAG_TE_ABORT_RAND) {
71			if (task->thread.per_flags & PER_FLAG_TE_ABORT_RAND_TEND)
72				cr2_new.tdc = 1;
73			else
74				cr2_new.tdc = 2;
75		}
76	}
77	/* Take care of enable/disable of guarded storage. */
78	if (MACHINE_HAS_GS) {
79		cr2_new.gse = 0;
80		if (task->thread.gs_cb)
81			cr2_new.gse = 1;
82	}
83	/* Load control register 0/2 iff changed */
84	cr0_changed = cr0_new.val != cr0_old.val;
85	cr2_changed = cr2_new.val != cr2_old.val;
86	if (cr0_changed)
87		local_ctl_load(0, &cr0_new.reg);
88	if (cr2_changed)
89		local_ctl_load(2, &cr2_new.reg);
90	/* Copy user specified PER registers */
91	new.control.val = thread->per_user.control;
92	new.start.val = thread->per_user.start;
93	new.end.val = thread->per_user.end;
94
95	/* merge TIF_SINGLE_STEP into user specified PER registers. */
96	if (test_tsk_thread_flag(task, TIF_SINGLE_STEP) ||
97	    test_tsk_thread_flag(task, TIF_UPROBE_SINGLESTEP)) {
98		if (test_tsk_thread_flag(task, TIF_BLOCK_STEP))
99			new.control.val |= PER_EVENT_BRANCH;
100		else
101			new.control.val |= PER_EVENT_IFETCH;
102		new.control.val |= PER_CONTROL_SUSPENSION;
103		new.control.val |= PER_EVENT_TRANSACTION_END;
104		if (test_tsk_thread_flag(task, TIF_UPROBE_SINGLESTEP))
105			new.control.val |= PER_EVENT_IFETCH;
106		new.start.val = 0;
107		new.end.val = -1UL;
108	}
109
110	/* Take care of the PER enablement bit in the PSW. */
111	if (!(new.control.val & PER_EVENT_MASK)) {
112		regs->psw.mask &= ~PSW_MASK_PER;
113		return;
114	}
115	regs->psw.mask |= PSW_MASK_PER;
116	__local_ctl_store(9, 11, old.regs);
117	if (memcmp(&new, &old, sizeof(struct per_regs)) != 0)
118		__local_ctl_load(9, 11, new.regs);
119}
120
121void user_enable_single_step(struct task_struct *task)
122{
123	clear_tsk_thread_flag(task, TIF_BLOCK_STEP);
124	set_tsk_thread_flag(task, TIF_SINGLE_STEP);
125}
126
127void user_disable_single_step(struct task_struct *task)
128{
129	clear_tsk_thread_flag(task, TIF_BLOCK_STEP);
130	clear_tsk_thread_flag(task, TIF_SINGLE_STEP);
131}
132
133void user_enable_block_step(struct task_struct *task)
134{
135	set_tsk_thread_flag(task, TIF_SINGLE_STEP);
136	set_tsk_thread_flag(task, TIF_BLOCK_STEP);
137}
138
139/*
140 * Called by kernel/ptrace.c when detaching..
141 *
142 * Clear all debugging related fields.
143 */
144void ptrace_disable(struct task_struct *task)
145{
146	memset(&task->thread.per_user, 0, sizeof(task->thread.per_user));
147	memset(&task->thread.per_event, 0, sizeof(task->thread.per_event));
148	clear_tsk_thread_flag(task, TIF_SINGLE_STEP);
149	clear_tsk_thread_flag(task, TIF_PER_TRAP);
150	task->thread.per_flags = 0;
151}
152
153#define __ADDR_MASK 7
154
155static inline unsigned long __peek_user_per(struct task_struct *child,
156					    addr_t addr)
157{
158	if (addr == offsetof(struct per_struct_kernel, cr9))
159		/* Control bits of the active per set. */
160		return test_thread_flag(TIF_SINGLE_STEP) ?
161			PER_EVENT_IFETCH : child->thread.per_user.control;
162	else if (addr == offsetof(struct per_struct_kernel, cr10))
163		/* Start address of the active per set. */
164		return test_thread_flag(TIF_SINGLE_STEP) ?
165			0 : child->thread.per_user.start;
166	else if (addr == offsetof(struct per_struct_kernel, cr11))
167		/* End address of the active per set. */
168		return test_thread_flag(TIF_SINGLE_STEP) ?
169			-1UL : child->thread.per_user.end;
170	else if (addr == offsetof(struct per_struct_kernel, bits))
171		/* Single-step bit. */
172		return test_thread_flag(TIF_SINGLE_STEP) ?
173			(1UL << (BITS_PER_LONG - 1)) : 0;
174	else if (addr == offsetof(struct per_struct_kernel, starting_addr))
175		/* Start address of the user specified per set. */
176		return child->thread.per_user.start;
177	else if (addr == offsetof(struct per_struct_kernel, ending_addr))
178		/* End address of the user specified per set. */
179		return child->thread.per_user.end;
180	else if (addr == offsetof(struct per_struct_kernel, perc_atmid))
181		/* PER code, ATMID and AI of the last PER trap */
182		return (unsigned long)
183			child->thread.per_event.cause << (BITS_PER_LONG - 16);
184	else if (addr == offsetof(struct per_struct_kernel, address))
185		/* Address of the last PER trap */
186		return child->thread.per_event.address;
187	else if (addr == offsetof(struct per_struct_kernel, access_id))
188		/* Access id of the last PER trap */
189		return (unsigned long)
190			child->thread.per_event.paid << (BITS_PER_LONG - 8);
191	return 0;
192}
193
194/*
195 * Read the word at offset addr from the user area of a process. The
196 * trouble here is that the information is littered over different
197 * locations. The process registers are found on the kernel stack,
198 * the floating point stuff and the trace settings are stored in
199 * the task structure. In addition the different structures in
200 * struct user contain pad bytes that should be read as zeroes.
201 * Lovely...
202 */
203static unsigned long __peek_user(struct task_struct *child, addr_t addr)
204{
205	addr_t offset, tmp;
206
207	if (addr < offsetof(struct user, regs.acrs)) {
208		/*
209		 * psw and gprs are stored on the stack
210		 */
211		tmp = *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr);
212		if (addr == offsetof(struct user, regs.psw.mask)) {
213			/* Return a clean psw mask. */
214			tmp &= PSW_MASK_USER | PSW_MASK_RI;
215			tmp |= PSW_USER_BITS;
216		}
217
218	} else if (addr < offsetof(struct user, regs.orig_gpr2)) {
219		/*
220		 * access registers are stored in the thread structure
221		 */
222		offset = addr - offsetof(struct user, regs.acrs);
223		/*
224		 * Very special case: old & broken 64 bit gdb reading
225		 * from acrs[15]. Result is a 64 bit value. Read the
226		 * 32 bit acrs[15] value and shift it by 32. Sick...
227		 */
228		if (addr == offsetof(struct user, regs.acrs[15]))
229			tmp = ((unsigned long) child->thread.acrs[15]) << 32;
230		else
231			tmp = *(addr_t *)((addr_t) &child->thread.acrs + offset);
232
233	} else if (addr == offsetof(struct user, regs.orig_gpr2)) {
234		/*
235		 * orig_gpr2 is stored on the kernel stack
236		 */
237		tmp = (addr_t) task_pt_regs(child)->orig_gpr2;
238
239	} else if (addr < offsetof(struct user, regs.fp_regs)) {
240		/*
241		 * prevent reads of padding hole between
242		 * orig_gpr2 and fp_regs on s390.
243		 */
244		tmp = 0;
245
246	} else if (addr == offsetof(struct user, regs.fp_regs.fpc)) {
247		/*
248		 * floating point control reg. is in the thread structure
249		 */
250		tmp = child->thread.ufpu.fpc;
251		tmp <<= BITS_PER_LONG - 32;
252
253	} else if (addr < offsetof(struct user, regs.fp_regs) + sizeof(s390_fp_regs)) {
254		/*
255		 * floating point regs. are in the child->thread.ufpu.vxrs array
256		 */
257		offset = addr - offsetof(struct user, regs.fp_regs.fprs);
258		tmp = *(addr_t *)((addr_t)child->thread.ufpu.vxrs + 2 * offset);
259	} else if (addr < offsetof(struct user, regs.per_info) + sizeof(per_struct)) {
260		/*
261		 * Handle access to the per_info structure.
262		 */
263		addr -= offsetof(struct user, regs.per_info);
264		tmp = __peek_user_per(child, addr);
265
266	} else
267		tmp = 0;
268
269	return tmp;
270}
271
272static int
273peek_user(struct task_struct *child, addr_t addr, addr_t data)
274{
275	addr_t tmp, mask;
276
277	/*
278	 * Stupid gdb peeks/pokes the access registers in 64 bit with
279	 * an alignment of 4. Programmers from hell...
280	 */
281	mask = __ADDR_MASK;
282	if (addr >= offsetof(struct user, regs.acrs) &&
283	    addr < offsetof(struct user, regs.orig_gpr2))
284		mask = 3;
285	if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
286		return -EIO;
287
288	tmp = __peek_user(child, addr);
289	return put_user(tmp, (addr_t __user *) data);
290}
291
292static inline void __poke_user_per(struct task_struct *child,
293				   addr_t addr, addr_t data)
294{
295	/*
296	 * There are only three fields in the per_info struct that the
297	 * debugger user can write to.
298	 * 1) cr9: the debugger wants to set a new PER event mask
299	 * 2) starting_addr: the debugger wants to set a new starting
300	 *    address to use with the PER event mask.
301	 * 3) ending_addr: the debugger wants to set a new ending
302	 *    address to use with the PER event mask.
303	 * The user specified PER event mask and the start and end
304	 * addresses are used only if single stepping is not in effect.
305	 * Writes to any other field in per_info are ignored.
306	 */
307	if (addr == offsetof(struct per_struct_kernel, cr9))
308		/* PER event mask of the user specified per set. */
309		child->thread.per_user.control =
310			data & (PER_EVENT_MASK | PER_CONTROL_MASK);
311	else if (addr == offsetof(struct per_struct_kernel, starting_addr))
312		/* Starting address of the user specified per set. */
313		child->thread.per_user.start = data;
314	else if (addr == offsetof(struct per_struct_kernel, ending_addr))
315		/* Ending address of the user specified per set. */
316		child->thread.per_user.end = data;
317}
318
319/*
320 * Write a word to the user area of a process at location addr. This
321 * operation does have an additional problem compared to peek_user.
322 * Stores to the program status word and on the floating point
323 * control register needs to get checked for validity.
324 */
325static int __poke_user(struct task_struct *child, addr_t addr, addr_t data)
326{
327	addr_t offset;
328
329
330	if (addr < offsetof(struct user, regs.acrs)) {
331		struct pt_regs *regs = task_pt_regs(child);
332		/*
333		 * psw and gprs are stored on the stack
334		 */
335		if (addr == offsetof(struct user, regs.psw.mask)) {
336			unsigned long mask = PSW_MASK_USER;
337
338			mask |= is_ri_task(child) ? PSW_MASK_RI : 0;
339			if ((data ^ PSW_USER_BITS) & ~mask)
340				/* Invalid psw mask. */
341				return -EINVAL;
342			if ((data & PSW_MASK_ASC) == PSW_ASC_HOME)
343				/* Invalid address-space-control bits */
344				return -EINVAL;
345			if ((data & PSW_MASK_EA) && !(data & PSW_MASK_BA))
346				/* Invalid addressing mode bits */
347				return -EINVAL;
348		}
349
350		if (test_pt_regs_flag(regs, PIF_SYSCALL) &&
351			addr == offsetof(struct user, regs.gprs[2])) {
352			struct pt_regs *regs = task_pt_regs(child);
353
354			regs->int_code = 0x20000 | (data & 0xffff);
355		}
356		*(addr_t *)((addr_t) &regs->psw + addr) = data;
357	} else if (addr < offsetof(struct user, regs.orig_gpr2)) {
358		/*
359		 * access registers are stored in the thread structure
360		 */
361		offset = addr - offsetof(struct user, regs.acrs);
362		/*
363		 * Very special case: old & broken 64 bit gdb writing
364		 * to acrs[15] with a 64 bit value. Ignore the lower
365		 * half of the value and write the upper 32 bit to
366		 * acrs[15]. Sick...
367		 */
368		if (addr == offsetof(struct user, regs.acrs[15]))
369			child->thread.acrs[15] = (unsigned int) (data >> 32);
370		else
371			*(addr_t *)((addr_t) &child->thread.acrs + offset) = data;
372
373	} else if (addr == offsetof(struct user, regs.orig_gpr2)) {
374		/*
375		 * orig_gpr2 is stored on the kernel stack
376		 */
377		task_pt_regs(child)->orig_gpr2 = data;
378
379	} else if (addr < offsetof(struct user, regs.fp_regs)) {
380		/*
381		 * prevent writes of padding hole between
382		 * orig_gpr2 and fp_regs on s390.
383		 */
384		return 0;
385
386	} else if (addr == offsetof(struct user, regs.fp_regs.fpc)) {
387		/*
388		 * floating point control reg. is in the thread structure
389		 */
390		if ((unsigned int)data != 0)
391			return -EINVAL;
392		child->thread.ufpu.fpc = data >> (BITS_PER_LONG - 32);
393
394	} else if (addr < offsetof(struct user, regs.fp_regs) + sizeof(s390_fp_regs)) {
395		/*
396		 * floating point regs. are in the child->thread.ufpu.vxrs array
397		 */
398		offset = addr - offsetof(struct user, regs.fp_regs.fprs);
399		*(addr_t *)((addr_t)child->thread.ufpu.vxrs + 2 * offset) = data;
400	} else if (addr < offsetof(struct user, regs.per_info) + sizeof(per_struct)) {
401		/*
402		 * Handle access to the per_info structure.
403		 */
404		addr -= offsetof(struct user, regs.per_info);
405		__poke_user_per(child, addr, data);
406
407	}
408
409	return 0;
410}
411
412static int poke_user(struct task_struct *child, addr_t addr, addr_t data)
413{
414	addr_t mask;
415
416	/*
417	 * Stupid gdb peeks/pokes the access registers in 64 bit with
418	 * an alignment of 4. Programmers from hell indeed...
419	 */
420	mask = __ADDR_MASK;
421	if (addr >= offsetof(struct user, regs.acrs) &&
422	    addr < offsetof(struct user, regs.orig_gpr2))
423		mask = 3;
424	if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
425		return -EIO;
426
427	return __poke_user(child, addr, data);
428}
429
430long arch_ptrace(struct task_struct *child, long request,
431		 unsigned long addr, unsigned long data)
432{
433	ptrace_area parea;
434	int copied, ret;
435
436	switch (request) {
437	case PTRACE_PEEKUSR:
438		/* read the word at location addr in the USER area. */
439		return peek_user(child, addr, data);
440
441	case PTRACE_POKEUSR:
442		/* write the word at location addr in the USER area */
443		return poke_user(child, addr, data);
444
445	case PTRACE_PEEKUSR_AREA:
446	case PTRACE_POKEUSR_AREA:
447		if (copy_from_user(&parea, (void __force __user *) addr,
448							sizeof(parea)))
449			return -EFAULT;
450		addr = parea.kernel_addr;
451		data = parea.process_addr;
452		copied = 0;
453		while (copied < parea.len) {
454			if (request == PTRACE_PEEKUSR_AREA)
455				ret = peek_user(child, addr, data);
456			else {
457				addr_t utmp;
458				if (get_user(utmp,
459					     (addr_t __force __user *) data))
460					return -EFAULT;
461				ret = poke_user(child, addr, utmp);
462			}
463			if (ret)
464				return ret;
465			addr += sizeof(unsigned long);
466			data += sizeof(unsigned long);
467			copied += sizeof(unsigned long);
468		}
469		return 0;
470	case PTRACE_GET_LAST_BREAK:
471		return put_user(child->thread.last_break, (unsigned long __user *)data);
472	case PTRACE_ENABLE_TE:
473		if (!MACHINE_HAS_TE)
474			return -EIO;
475		child->thread.per_flags &= ~PER_FLAG_NO_TE;
476		return 0;
477	case PTRACE_DISABLE_TE:
478		if (!MACHINE_HAS_TE)
479			return -EIO;
480		child->thread.per_flags |= PER_FLAG_NO_TE;
481		child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND;
482		return 0;
483	case PTRACE_TE_ABORT_RAND:
484		if (!MACHINE_HAS_TE || (child->thread.per_flags & PER_FLAG_NO_TE))
485			return -EIO;
486		switch (data) {
487		case 0UL:
488			child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND;
489			break;
490		case 1UL:
491			child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND;
492			child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND_TEND;
493			break;
494		case 2UL:
495			child->thread.per_flags |= PER_FLAG_TE_ABORT_RAND;
496			child->thread.per_flags &= ~PER_FLAG_TE_ABORT_RAND_TEND;
497			break;
498		default:
499			return -EINVAL;
500		}
501		return 0;
502	default:
503		return ptrace_request(child, request, addr, data);
504	}
505}
506
507#ifdef CONFIG_COMPAT
508/*
509 * Now the fun part starts... a 31 bit program running in the
510 * 31 bit emulation tracing another program. PTRACE_PEEKTEXT,
511 * PTRACE_PEEKDATA, PTRACE_POKETEXT and PTRACE_POKEDATA are easy
512 * to handle, the difference to the 64 bit versions of the requests
513 * is that the access is done in multiples of 4 byte instead of
514 * 8 bytes (sizeof(unsigned long) on 31/64 bit).
515 * The ugly part are PTRACE_PEEKUSR, PTRACE_PEEKUSR_AREA,
516 * PTRACE_POKEUSR and PTRACE_POKEUSR_AREA. If the traced program
517 * is a 31 bit program too, the content of struct user can be
518 * emulated. A 31 bit program peeking into the struct user of
519 * a 64 bit program is a no-no.
520 */
521
522/*
523 * Same as peek_user_per but for a 31 bit program.
524 */
525static inline __u32 __peek_user_per_compat(struct task_struct *child,
526					   addr_t addr)
527{
528	if (addr == offsetof(struct compat_per_struct_kernel, cr9))
529		/* Control bits of the active per set. */
530		return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
531			PER_EVENT_IFETCH : child->thread.per_user.control;
532	else if (addr == offsetof(struct compat_per_struct_kernel, cr10))
533		/* Start address of the active per set. */
534		return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
535			0 : child->thread.per_user.start;
536	else if (addr == offsetof(struct compat_per_struct_kernel, cr11))
537		/* End address of the active per set. */
538		return test_thread_flag(TIF_SINGLE_STEP) ?
539			PSW32_ADDR_INSN : child->thread.per_user.end;
540	else if (addr == offsetof(struct compat_per_struct_kernel, bits))
541		/* Single-step bit. */
542		return (__u32) test_thread_flag(TIF_SINGLE_STEP) ?
543			0x80000000 : 0;
544	else if (addr == offsetof(struct compat_per_struct_kernel, starting_addr))
545		/* Start address of the user specified per set. */
546		return (__u32) child->thread.per_user.start;
547	else if (addr == offsetof(struct compat_per_struct_kernel, ending_addr))
548		/* End address of the user specified per set. */
549		return (__u32) child->thread.per_user.end;
550	else if (addr == offsetof(struct compat_per_struct_kernel, perc_atmid))
551		/* PER code, ATMID and AI of the last PER trap */
552		return (__u32) child->thread.per_event.cause << 16;
553	else if (addr == offsetof(struct compat_per_struct_kernel, address))
554		/* Address of the last PER trap */
555		return (__u32) child->thread.per_event.address;
556	else if (addr == offsetof(struct compat_per_struct_kernel, access_id))
557		/* Access id of the last PER trap */
558		return (__u32) child->thread.per_event.paid << 24;
559	return 0;
560}
561
562/*
563 * Same as peek_user but for a 31 bit program.
564 */
565static u32 __peek_user_compat(struct task_struct *child, addr_t addr)
566{
567	addr_t offset;
568	__u32 tmp;
569
570	if (addr < offsetof(struct compat_user, regs.acrs)) {
571		struct pt_regs *regs = task_pt_regs(child);
572		/*
573		 * psw and gprs are stored on the stack
574		 */
575		if (addr == offsetof(struct compat_user, regs.psw.mask)) {
576			/* Fake a 31 bit psw mask. */
577			tmp = (__u32)(regs->psw.mask >> 32);
578			tmp &= PSW32_MASK_USER | PSW32_MASK_RI;
579			tmp |= PSW32_USER_BITS;
580		} else if (addr == offsetof(struct compat_user, regs.psw.addr)) {
581			/* Fake a 31 bit psw address. */
582			tmp = (__u32) regs->psw.addr |
583				(__u32)(regs->psw.mask & PSW_MASK_BA);
584		} else {
585			/* gpr 0-15 */
586			tmp = *(__u32 *)((addr_t) &regs->psw + addr*2 + 4);
587		}
588	} else if (addr < offsetof(struct compat_user, regs.orig_gpr2)) {
589		/*
590		 * access registers are stored in the thread structure
591		 */
592		offset = addr - offsetof(struct compat_user, regs.acrs);
593		tmp = *(__u32*)((addr_t) &child->thread.acrs + offset);
594
595	} else if (addr == offsetof(struct compat_user, regs.orig_gpr2)) {
596		/*
597		 * orig_gpr2 is stored on the kernel stack
598		 */
599		tmp = *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4);
600
601	} else if (addr < offsetof(struct compat_user, regs.fp_regs)) {
602		/*
603		 * prevent reads of padding hole between
604		 * orig_gpr2 and fp_regs on s390.
605		 */
606		tmp = 0;
607
608	} else if (addr == offsetof(struct compat_user, regs.fp_regs.fpc)) {
609		/*
610		 * floating point control reg. is in the thread structure
611		 */
612		tmp = child->thread.ufpu.fpc;
613
614	} else if (addr < offsetof(struct compat_user, regs.fp_regs) + sizeof(s390_fp_regs)) {
615		/*
616		 * floating point regs. are in the child->thread.ufpu.vxrs array
617		 */
618		offset = addr - offsetof(struct compat_user, regs.fp_regs.fprs);
619		tmp = *(__u32 *)((addr_t)child->thread.ufpu.vxrs + 2 * offset);
620	} else if (addr < offsetof(struct compat_user, regs.per_info) + sizeof(struct compat_per_struct_kernel)) {
621		/*
622		 * Handle access to the per_info structure.
623		 */
624		addr -= offsetof(struct compat_user, regs.per_info);
625		tmp = __peek_user_per_compat(child, addr);
626
627	} else
628		tmp = 0;
629
630	return tmp;
631}
632
633static int peek_user_compat(struct task_struct *child,
634			    addr_t addr, addr_t data)
635{
636	__u32 tmp;
637
638	if (!is_compat_task() || (addr & 3) || addr > sizeof(struct user) - 3)
639		return -EIO;
640
641	tmp = __peek_user_compat(child, addr);
642	return put_user(tmp, (__u32 __user *) data);
643}
644
645/*
646 * Same as poke_user_per but for a 31 bit program.
647 */
648static inline void __poke_user_per_compat(struct task_struct *child,
649					  addr_t addr, __u32 data)
650{
651	if (addr == offsetof(struct compat_per_struct_kernel, cr9))
652		/* PER event mask of the user specified per set. */
653		child->thread.per_user.control =
654			data & (PER_EVENT_MASK | PER_CONTROL_MASK);
655	else if (addr == offsetof(struct compat_per_struct_kernel, starting_addr))
656		/* Starting address of the user specified per set. */
657		child->thread.per_user.start = data;
658	else if (addr == offsetof(struct compat_per_struct_kernel, ending_addr))
659		/* Ending address of the user specified per set. */
660		child->thread.per_user.end = data;
661}
662
663/*
664 * Same as poke_user but for a 31 bit program.
665 */
666static int __poke_user_compat(struct task_struct *child,
667			      addr_t addr, addr_t data)
668{
669	__u32 tmp = (__u32) data;
670	addr_t offset;
671
672	if (addr < offsetof(struct compat_user, regs.acrs)) {
673		struct pt_regs *regs = task_pt_regs(child);
674		/*
675		 * psw, gprs, acrs and orig_gpr2 are stored on the stack
676		 */
677		if (addr == offsetof(struct compat_user, regs.psw.mask)) {
678			__u32 mask = PSW32_MASK_USER;
679
680			mask |= is_ri_task(child) ? PSW32_MASK_RI : 0;
681			/* Build a 64 bit psw mask from 31 bit mask. */
682			if ((tmp ^ PSW32_USER_BITS) & ~mask)
683				/* Invalid psw mask. */
684				return -EINVAL;
685			if ((data & PSW32_MASK_ASC) == PSW32_ASC_HOME)
686				/* Invalid address-space-control bits */
687				return -EINVAL;
688			regs->psw.mask = (regs->psw.mask & ~PSW_MASK_USER) |
689				(regs->psw.mask & PSW_MASK_BA) |
690				(__u64)(tmp & mask) << 32;
691		} else if (addr == offsetof(struct compat_user, regs.psw.addr)) {
692			/* Build a 64 bit psw address from 31 bit address. */
693			regs->psw.addr = (__u64) tmp & PSW32_ADDR_INSN;
694			/* Transfer 31 bit amode bit to psw mask. */
695			regs->psw.mask = (regs->psw.mask & ~PSW_MASK_BA) |
696				(__u64)(tmp & PSW32_ADDR_AMODE);
697		} else {
698			if (test_pt_regs_flag(regs, PIF_SYSCALL) &&
699				addr == offsetof(struct compat_user, regs.gprs[2])) {
700				struct pt_regs *regs = task_pt_regs(child);
701
702				regs->int_code = 0x20000 | (data & 0xffff);
703			}
704			/* gpr 0-15 */
705			*(__u32*)((addr_t) &regs->psw + addr*2 + 4) = tmp;
706		}
707	} else if (addr < offsetof(struct compat_user, regs.orig_gpr2)) {
708		/*
709		 * access registers are stored in the thread structure
710		 */
711		offset = addr - offsetof(struct compat_user, regs.acrs);
712		*(__u32*)((addr_t) &child->thread.acrs + offset) = tmp;
713
714	} else if (addr == offsetof(struct compat_user, regs.orig_gpr2)) {
715		/*
716		 * orig_gpr2 is stored on the kernel stack
717		 */
718		*(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4) = tmp;
719
720	} else if (addr < offsetof(struct compat_user, regs.fp_regs)) {
721		/*
722		 * prevent writess of padding hole between
723		 * orig_gpr2 and fp_regs on s390.
724		 */
725		return 0;
726
727	} else if (addr == offsetof(struct compat_user, regs.fp_regs.fpc)) {
728		/*
729		 * floating point control reg. is in the thread structure
730		 */
731		child->thread.ufpu.fpc = data;
732
733	} else if (addr < offsetof(struct compat_user, regs.fp_regs) + sizeof(s390_fp_regs)) {
734		/*
735		 * floating point regs. are in the child->thread.ufpu.vxrs array
736		 */
737		offset = addr - offsetof(struct compat_user, regs.fp_regs.fprs);
738		*(__u32 *)((addr_t)child->thread.ufpu.vxrs + 2 * offset) = tmp;
739	} else if (addr < offsetof(struct compat_user, regs.per_info) + sizeof(struct compat_per_struct_kernel)) {
740		/*
741		 * Handle access to the per_info structure.
742		 */
743		addr -= offsetof(struct compat_user, regs.per_info);
744		__poke_user_per_compat(child, addr, data);
745	}
746
747	return 0;
748}
749
750static int poke_user_compat(struct task_struct *child,
751			    addr_t addr, addr_t data)
752{
753	if (!is_compat_task() || (addr & 3) ||
754	    addr > sizeof(struct compat_user) - 3)
755		return -EIO;
756
757	return __poke_user_compat(child, addr, data);
758}
759
760long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
761			compat_ulong_t caddr, compat_ulong_t cdata)
762{
763	unsigned long addr = caddr;
764	unsigned long data = cdata;
765	compat_ptrace_area parea;
766	int copied, ret;
767
768	switch (request) {
769	case PTRACE_PEEKUSR:
770		/* read the word at location addr in the USER area. */
771		return peek_user_compat(child, addr, data);
772
773	case PTRACE_POKEUSR:
774		/* write the word at location addr in the USER area */
775		return poke_user_compat(child, addr, data);
776
777	case PTRACE_PEEKUSR_AREA:
778	case PTRACE_POKEUSR_AREA:
779		if (copy_from_user(&parea, (void __force __user *) addr,
780							sizeof(parea)))
781			return -EFAULT;
782		addr = parea.kernel_addr;
783		data = parea.process_addr;
784		copied = 0;
785		while (copied < parea.len) {
786			if (request == PTRACE_PEEKUSR_AREA)
787				ret = peek_user_compat(child, addr, data);
788			else {
789				__u32 utmp;
790				if (get_user(utmp,
791					     (__u32 __force __user *) data))
792					return -EFAULT;
793				ret = poke_user_compat(child, addr, utmp);
794			}
795			if (ret)
796				return ret;
797			addr += sizeof(unsigned int);
798			data += sizeof(unsigned int);
799			copied += sizeof(unsigned int);
800		}
801		return 0;
802	case PTRACE_GET_LAST_BREAK:
803		return put_user(child->thread.last_break, (unsigned int __user *)data);
804	}
805	return compat_ptrace_request(child, request, addr, data);
806}
807#endif
808
809/*
810 * user_regset definitions.
811 */
812
813static int s390_regs_get(struct task_struct *target,
814			 const struct user_regset *regset,
815			 struct membuf to)
816{
817	unsigned pos;
818	if (target == current)
819		save_access_regs(target->thread.acrs);
820
821	for (pos = 0; pos < sizeof(s390_regs); pos += sizeof(long))
822		membuf_store(&to, __peek_user(target, pos));
823	return 0;
824}
825
826static int s390_regs_set(struct task_struct *target,
827			 const struct user_regset *regset,
828			 unsigned int pos, unsigned int count,
829			 const void *kbuf, const void __user *ubuf)
830{
831	int rc = 0;
832
833	if (target == current)
834		save_access_regs(target->thread.acrs);
835
836	if (kbuf) {
837		const unsigned long *k = kbuf;
838		while (count > 0 && !rc) {
839			rc = __poke_user(target, pos, *k++);
840			count -= sizeof(*k);
841			pos += sizeof(*k);
842		}
843	} else {
844		const unsigned long  __user *u = ubuf;
845		while (count > 0 && !rc) {
846			unsigned long word;
847			rc = __get_user(word, u++);
848			if (rc)
849				break;
850			rc = __poke_user(target, pos, word);
851			count -= sizeof(*u);
852			pos += sizeof(*u);
853		}
854	}
855
856	if (rc == 0 && target == current)
857		restore_access_regs(target->thread.acrs);
858
859	return rc;
860}
861
862static int s390_fpregs_get(struct task_struct *target,
863			   const struct user_regset *regset,
864			   struct membuf to)
865{
866	_s390_fp_regs fp_regs;
867
868	if (target == current)
869		save_user_fpu_regs();
870
871	fp_regs.fpc = target->thread.ufpu.fpc;
872	fpregs_store(&fp_regs, &target->thread.ufpu);
873
874	return membuf_write(&to, &fp_regs, sizeof(fp_regs));
875}
876
877static int s390_fpregs_set(struct task_struct *target,
878			   const struct user_regset *regset, unsigned int pos,
879			   unsigned int count, const void *kbuf,
880			   const void __user *ubuf)
881{
882	int rc = 0;
883	freg_t fprs[__NUM_FPRS];
884
885	if (target == current)
886		save_user_fpu_regs();
887	convert_vx_to_fp(fprs, target->thread.ufpu.vxrs);
888	if (count > 0 && pos < offsetof(s390_fp_regs, fprs)) {
889		u32 ufpc[2] = { target->thread.ufpu.fpc, 0 };
890		rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ufpc,
891					0, offsetof(s390_fp_regs, fprs));
892		if (rc)
893			return rc;
894		if (ufpc[1] != 0)
895			return -EINVAL;
896		target->thread.ufpu.fpc = ufpc[0];
897	}
898
899	if (rc == 0 && count > 0)
900		rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
901					fprs, offsetof(s390_fp_regs, fprs), -1);
902	if (rc)
903		return rc;
904	convert_fp_to_vx(target->thread.ufpu.vxrs, fprs);
905	return rc;
906}
907
908static int s390_last_break_get(struct task_struct *target,
909			       const struct user_regset *regset,
910			       struct membuf to)
911{
912	return membuf_store(&to, target->thread.last_break);
913}
914
915static int s390_last_break_set(struct task_struct *target,
916			       const struct user_regset *regset,
917			       unsigned int pos, unsigned int count,
918			       const void *kbuf, const void __user *ubuf)
919{
920	return 0;
921}
922
923static int s390_tdb_get(struct task_struct *target,
924			const struct user_regset *regset,
925			struct membuf to)
926{
927	struct pt_regs *regs = task_pt_regs(target);
928	size_t size;
929
930	if (!(regs->int_code & 0x200))
931		return -ENODATA;
932	size = sizeof(target->thread.trap_tdb.data);
933	return membuf_write(&to, target->thread.trap_tdb.data, size);
934}
935
936static int s390_tdb_set(struct task_struct *target,
937			const struct user_regset *regset,
938			unsigned int pos, unsigned int count,
939			const void *kbuf, const void __user *ubuf)
940{
941	return 0;
942}
943
944static int s390_vxrs_low_get(struct task_struct *target,
945			     const struct user_regset *regset,
946			     struct membuf to)
947{
948	__u64 vxrs[__NUM_VXRS_LOW];
949	int i;
950
951	if (!cpu_has_vx())
952		return -ENODEV;
953	if (target == current)
954		save_user_fpu_regs();
955	for (i = 0; i < __NUM_VXRS_LOW; i++)
956		vxrs[i] = target->thread.ufpu.vxrs[i].low;
957	return membuf_write(&to, vxrs, sizeof(vxrs));
958}
959
960static int s390_vxrs_low_set(struct task_struct *target,
961			     const struct user_regset *regset,
962			     unsigned int pos, unsigned int count,
963			     const void *kbuf, const void __user *ubuf)
964{
965	__u64 vxrs[__NUM_VXRS_LOW];
966	int i, rc;
967
968	if (!cpu_has_vx())
969		return -ENODEV;
970	if (target == current)
971		save_user_fpu_regs();
972
973	for (i = 0; i < __NUM_VXRS_LOW; i++)
974		vxrs[i] = target->thread.ufpu.vxrs[i].low;
975
976	rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, vxrs, 0, -1);
977	if (rc == 0)
978		for (i = 0; i < __NUM_VXRS_LOW; i++)
979			target->thread.ufpu.vxrs[i].low = vxrs[i];
980
981	return rc;
982}
983
984static int s390_vxrs_high_get(struct task_struct *target,
985			      const struct user_regset *regset,
986			      struct membuf to)
987{
988	if (!cpu_has_vx())
989		return -ENODEV;
990	if (target == current)
991		save_user_fpu_regs();
992	return membuf_write(&to, target->thread.ufpu.vxrs + __NUM_VXRS_LOW,
993			    __NUM_VXRS_HIGH * sizeof(__vector128));
994}
995
996static int s390_vxrs_high_set(struct task_struct *target,
997			      const struct user_regset *regset,
998			      unsigned int pos, unsigned int count,
999			      const void *kbuf, const void __user *ubuf)
1000{
1001	int rc;
1002
1003	if (!cpu_has_vx())
1004		return -ENODEV;
1005	if (target == current)
1006		save_user_fpu_regs();
1007
1008	rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1009				target->thread.ufpu.vxrs + __NUM_VXRS_LOW, 0, -1);
1010	return rc;
1011}
1012
1013static int s390_system_call_get(struct task_struct *target,
1014				const struct user_regset *regset,
1015				struct membuf to)
1016{
1017	return membuf_store(&to, target->thread.system_call);
1018}
1019
1020static int s390_system_call_set(struct task_struct *target,
1021				const struct user_regset *regset,
1022				unsigned int pos, unsigned int count,
1023				const void *kbuf, const void __user *ubuf)
1024{
1025	unsigned int *data = &target->thread.system_call;
1026	return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1027				  data, 0, sizeof(unsigned int));
1028}
1029
1030static int s390_gs_cb_get(struct task_struct *target,
1031			  const struct user_regset *regset,
1032			  struct membuf to)
1033{
1034	struct gs_cb *data = target->thread.gs_cb;
1035
1036	if (!MACHINE_HAS_GS)
1037		return -ENODEV;
1038	if (!data)
1039		return -ENODATA;
1040	if (target == current)
1041		save_gs_cb(data);
1042	return membuf_write(&to, data, sizeof(struct gs_cb));
1043}
1044
1045static int s390_gs_cb_set(struct task_struct *target,
1046			  const struct user_regset *regset,
1047			  unsigned int pos, unsigned int count,
1048			  const void *kbuf, const void __user *ubuf)
1049{
1050	struct gs_cb gs_cb = { }, *data = NULL;
1051	int rc;
1052
1053	if (!MACHINE_HAS_GS)
1054		return -ENODEV;
1055	if (!target->thread.gs_cb) {
1056		data = kzalloc(sizeof(*data), GFP_KERNEL);
1057		if (!data)
1058			return -ENOMEM;
1059	}
1060	if (!target->thread.gs_cb)
1061		gs_cb.gsd = 25;
1062	else if (target == current)
1063		save_gs_cb(&gs_cb);
1064	else
1065		gs_cb = *target->thread.gs_cb;
1066	rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1067				&gs_cb, 0, sizeof(gs_cb));
1068	if (rc) {
1069		kfree(data);
1070		return -EFAULT;
1071	}
1072	preempt_disable();
1073	if (!target->thread.gs_cb)
1074		target->thread.gs_cb = data;
1075	*target->thread.gs_cb = gs_cb;
1076	if (target == current) {
1077		local_ctl_set_bit(2, CR2_GUARDED_STORAGE_BIT);
1078		restore_gs_cb(target->thread.gs_cb);
1079	}
1080	preempt_enable();
1081	return rc;
1082}
1083
1084static int s390_gs_bc_get(struct task_struct *target,
1085			  const struct user_regset *regset,
1086			  struct membuf to)
1087{
1088	struct gs_cb *data = target->thread.gs_bc_cb;
1089
1090	if (!MACHINE_HAS_GS)
1091		return -ENODEV;
1092	if (!data)
1093		return -ENODATA;
1094	return membuf_write(&to, data, sizeof(struct gs_cb));
1095}
1096
1097static int s390_gs_bc_set(struct task_struct *target,
1098			  const struct user_regset *regset,
1099			  unsigned int pos, unsigned int count,
1100			  const void *kbuf, const void __user *ubuf)
1101{
1102	struct gs_cb *data = target->thread.gs_bc_cb;
1103
1104	if (!MACHINE_HAS_GS)
1105		return -ENODEV;
1106	if (!data) {
1107		data = kzalloc(sizeof(*data), GFP_KERNEL);
1108		if (!data)
1109			return -ENOMEM;
1110		target->thread.gs_bc_cb = data;
1111	}
1112	return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1113				  data, 0, sizeof(struct gs_cb));
1114}
1115
1116static bool is_ri_cb_valid(struct runtime_instr_cb *cb)
1117{
1118	return (cb->rca & 0x1f) == 0 &&
1119		(cb->roa & 0xfff) == 0 &&
1120		(cb->rla & 0xfff) == 0xfff &&
1121		cb->s == 1 &&
1122		cb->k == 1 &&
1123		cb->h == 0 &&
1124		cb->reserved1 == 0 &&
1125		cb->ps == 1 &&
1126		cb->qs == 0 &&
1127		cb->pc == 1 &&
1128		cb->qc == 0 &&
1129		cb->reserved2 == 0 &&
1130		cb->reserved3 == 0 &&
1131		cb->reserved4 == 0 &&
1132		cb->reserved5 == 0 &&
1133		cb->reserved6 == 0 &&
1134		cb->reserved7 == 0 &&
1135		cb->reserved8 == 0 &&
1136		cb->rla >= cb->roa &&
1137		cb->rca >= cb->roa &&
1138		cb->rca <= cb->rla+1 &&
1139		cb->m < 3;
1140}
1141
1142static int s390_runtime_instr_get(struct task_struct *target,
1143				const struct user_regset *regset,
1144				struct membuf to)
1145{
1146	struct runtime_instr_cb *data = target->thread.ri_cb;
1147
1148	if (!test_facility(64))
1149		return -ENODEV;
1150	if (!data)
1151		return -ENODATA;
1152
1153	return membuf_write(&to, data, sizeof(struct runtime_instr_cb));
1154}
1155
1156static int s390_runtime_instr_set(struct task_struct *target,
1157				  const struct user_regset *regset,
1158				  unsigned int pos, unsigned int count,
1159				  const void *kbuf, const void __user *ubuf)
1160{
1161	struct runtime_instr_cb ri_cb = { }, *data = NULL;
1162	int rc;
1163
1164	if (!test_facility(64))
1165		return -ENODEV;
1166
1167	if (!target->thread.ri_cb) {
1168		data = kzalloc(sizeof(*data), GFP_KERNEL);
1169		if (!data)
1170			return -ENOMEM;
1171	}
1172
1173	if (target->thread.ri_cb) {
1174		if (target == current)
1175			store_runtime_instr_cb(&ri_cb);
1176		else
1177			ri_cb = *target->thread.ri_cb;
1178	}
1179
1180	rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
1181				&ri_cb, 0, sizeof(struct runtime_instr_cb));
1182	if (rc) {
1183		kfree(data);
1184		return -EFAULT;
1185	}
1186
1187	if (!is_ri_cb_valid(&ri_cb)) {
1188		kfree(data);
1189		return -EINVAL;
1190	}
1191	/*
1192	 * Override access key in any case, since user space should
1193	 * not be able to set it, nor should it care about it.
1194	 */
1195	ri_cb.key = PAGE_DEFAULT_KEY >> 4;
1196	preempt_disable();
1197	if (!target->thread.ri_cb)
1198		target->thread.ri_cb = data;
1199	*target->thread.ri_cb = ri_cb;
1200	if (target == current)
1201		load_runtime_instr_cb(target->thread.ri_cb);
1202	preempt_enable();
1203
1204	return 0;
1205}
1206
1207static const struct user_regset s390_regsets[] = {
1208	{
1209		.core_note_type = NT_PRSTATUS,
1210		.n = sizeof(s390_regs) / sizeof(long),
1211		.size = sizeof(long),
1212		.align = sizeof(long),
1213		.regset_get = s390_regs_get,
1214		.set = s390_regs_set,
1215	},
1216	{
1217		.core_note_type = NT_PRFPREG,
1218		.n = sizeof(s390_fp_regs) / sizeof(long),
1219		.size = sizeof(long),
1220		.align = sizeof(long),
1221		.regset_get = s390_fpregs_get,
1222		.set = s390_fpregs_set,
1223	},
1224	{
1225		.core_note_type = NT_S390_SYSTEM_CALL,
1226		.n = 1,
1227		.size = sizeof(unsigned int),
1228		.align = sizeof(unsigned int),
1229		.regset_get = s390_system_call_get,
1230		.set = s390_system_call_set,
1231	},
1232	{
1233		.core_note_type = NT_S390_LAST_BREAK,
1234		.n = 1,
1235		.size = sizeof(long),
1236		.align = sizeof(long),
1237		.regset_get = s390_last_break_get,
1238		.set = s390_last_break_set,
1239	},
1240	{
1241		.core_note_type = NT_S390_TDB,
1242		.n = 1,
1243		.size = 256,
1244		.align = 1,
1245		.regset_get = s390_tdb_get,
1246		.set = s390_tdb_set,
1247	},
1248	{
1249		.core_note_type = NT_S390_VXRS_LOW,
1250		.n = __NUM_VXRS_LOW,
1251		.size = sizeof(__u64),
1252		.align = sizeof(__u64),
1253		.regset_get = s390_vxrs_low_get,
1254		.set = s390_vxrs_low_set,
1255	},
1256	{
1257		.core_note_type = NT_S390_VXRS_HIGH,
1258		.n = __NUM_VXRS_HIGH,
1259		.size = sizeof(__vector128),
1260		.align = sizeof(__vector128),
1261		.regset_get = s390_vxrs_high_get,
1262		.set = s390_vxrs_high_set,
1263	},
1264	{
1265		.core_note_type = NT_S390_GS_CB,
1266		.n = sizeof(struct gs_cb) / sizeof(__u64),
1267		.size = sizeof(__u64),
1268		.align = sizeof(__u64),
1269		.regset_get = s390_gs_cb_get,
1270		.set = s390_gs_cb_set,
1271	},
1272	{
1273		.core_note_type = NT_S390_GS_BC,
1274		.n = sizeof(struct gs_cb) / sizeof(__u64),
1275		.size = sizeof(__u64),
1276		.align = sizeof(__u64),
1277		.regset_get = s390_gs_bc_get,
1278		.set = s390_gs_bc_set,
1279	},
1280	{
1281		.core_note_type = NT_S390_RI_CB,
1282		.n = sizeof(struct runtime_instr_cb) / sizeof(__u64),
1283		.size = sizeof(__u64),
1284		.align = sizeof(__u64),
1285		.regset_get = s390_runtime_instr_get,
1286		.set = s390_runtime_instr_set,
1287	},
1288};
1289
1290static const struct user_regset_view user_s390_view = {
1291	.name = "s390x",
1292	.e_machine = EM_S390,
1293	.regsets = s390_regsets,
1294	.n = ARRAY_SIZE(s390_regsets)
1295};
1296
1297#ifdef CONFIG_COMPAT
1298static int s390_compat_regs_get(struct task_struct *target,
1299				const struct user_regset *regset,
1300				struct membuf to)
1301{
1302	unsigned n;
1303
1304	if (target == current)
1305		save_access_regs(target->thread.acrs);
1306
1307	for (n = 0; n < sizeof(s390_compat_regs); n += sizeof(compat_ulong_t))
1308		membuf_store(&to, __peek_user_compat(target, n));
1309	return 0;
1310}
1311
1312static int s390_compat_regs_set(struct task_struct *target,
1313				const struct user_regset *regset,
1314				unsigned int pos, unsigned int count,
1315				const void *kbuf, const void __user *ubuf)
1316{
1317	int rc = 0;
1318
1319	if (target == current)
1320		save_access_regs(target->thread.acrs);
1321
1322	if (kbuf) {
1323		const compat_ulong_t *k = kbuf;
1324		while (count > 0 && !rc) {
1325			rc = __poke_user_compat(target, pos, *k++);
1326			count -= sizeof(*k);
1327			pos += sizeof(*k);
1328		}
1329	} else {
1330		const compat_ulong_t  __user *u = ubuf;
1331		while (count > 0 && !rc) {
1332			compat_ulong_t word;
1333			rc = __get_user(word, u++);
1334			if (rc)
1335				break;
1336			rc = __poke_user_compat(target, pos, word);
1337			count -= sizeof(*u);
1338			pos += sizeof(*u);
1339		}
1340	}
1341
1342	if (rc == 0 && target == current)
1343		restore_access_regs(target->thread.acrs);
1344
1345	return rc;
1346}
1347
1348static int s390_compat_regs_high_get(struct task_struct *target,
1349				     const struct user_regset *regset,
1350				     struct membuf to)
1351{
1352	compat_ulong_t *gprs_high;
1353	int i;
1354
1355	gprs_high = (compat_ulong_t *)task_pt_regs(target)->gprs;
1356	for (i = 0; i < NUM_GPRS; i++, gprs_high += 2)
1357		membuf_store(&to, *gprs_high);
1358	return 0;
1359}
1360
1361static int s390_compat_regs_high_set(struct task_struct *target,
1362				     const struct user_regset *regset,
1363				     unsigned int pos, unsigned int count,
1364				     const void *kbuf, const void __user *ubuf)
1365{
1366	compat_ulong_t *gprs_high;
1367	int rc = 0;
1368
1369	gprs_high = (compat_ulong_t *)
1370		&task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)];
1371	if (kbuf) {
1372		const compat_ulong_t *k = kbuf;
1373		while (count > 0) {
1374			*gprs_high = *k++;
1375			*gprs_high += 2;
1376			count -= sizeof(*k);
1377		}
1378	} else {
1379		const compat_ulong_t  __user *u = ubuf;
1380		while (count > 0 && !rc) {
1381			unsigned long word;
1382			rc = __get_user(word, u++);
1383			if (rc)
1384				break;
1385			*gprs_high = word;
1386			*gprs_high += 2;
1387			count -= sizeof(*u);
1388		}
1389	}
1390
1391	return rc;
1392}
1393
1394static int s390_compat_last_break_get(struct task_struct *target,
1395				      const struct user_regset *regset,
1396				      struct membuf to)
1397{
1398	compat_ulong_t last_break = target->thread.last_break;
1399
1400	return membuf_store(&to, (unsigned long)last_break);
1401}
1402
1403static int s390_compat_last_break_set(struct task_struct *target,
1404				      const struct user_regset *regset,
1405				      unsigned int pos, unsigned int count,
1406				      const void *kbuf, const void __user *ubuf)
1407{
1408	return 0;
1409}
1410
1411static const struct user_regset s390_compat_regsets[] = {
1412	{
1413		.core_note_type = NT_PRSTATUS,
1414		.n = sizeof(s390_compat_regs) / sizeof(compat_long_t),
1415		.size = sizeof(compat_long_t),
1416		.align = sizeof(compat_long_t),
1417		.regset_get = s390_compat_regs_get,
1418		.set = s390_compat_regs_set,
1419	},
1420	{
1421		.core_note_type = NT_PRFPREG,
1422		.n = sizeof(s390_fp_regs) / sizeof(compat_long_t),
1423		.size = sizeof(compat_long_t),
1424		.align = sizeof(compat_long_t),
1425		.regset_get = s390_fpregs_get,
1426		.set = s390_fpregs_set,
1427	},
1428	{
1429		.core_note_type = NT_S390_SYSTEM_CALL,
1430		.n = 1,
1431		.size = sizeof(compat_uint_t),
1432		.align = sizeof(compat_uint_t),
1433		.regset_get = s390_system_call_get,
1434		.set = s390_system_call_set,
1435	},
1436	{
1437		.core_note_type = NT_S390_LAST_BREAK,
1438		.n = 1,
1439		.size = sizeof(long),
1440		.align = sizeof(long),
1441		.regset_get = s390_compat_last_break_get,
1442		.set = s390_compat_last_break_set,
1443	},
1444	{
1445		.core_note_type = NT_S390_TDB,
1446		.n = 1,
1447		.size = 256,
1448		.align = 1,
1449		.regset_get = s390_tdb_get,
1450		.set = s390_tdb_set,
1451	},
1452	{
1453		.core_note_type = NT_S390_VXRS_LOW,
1454		.n = __NUM_VXRS_LOW,
1455		.size = sizeof(__u64),
1456		.align = sizeof(__u64),
1457		.regset_get = s390_vxrs_low_get,
1458		.set = s390_vxrs_low_set,
1459	},
1460	{
1461		.core_note_type = NT_S390_VXRS_HIGH,
1462		.n = __NUM_VXRS_HIGH,
1463		.size = sizeof(__vector128),
1464		.align = sizeof(__vector128),
1465		.regset_get = s390_vxrs_high_get,
1466		.set = s390_vxrs_high_set,
1467	},
1468	{
1469		.core_note_type = NT_S390_HIGH_GPRS,
1470		.n = sizeof(s390_compat_regs_high) / sizeof(compat_long_t),
1471		.size = sizeof(compat_long_t),
1472		.align = sizeof(compat_long_t),
1473		.regset_get = s390_compat_regs_high_get,
1474		.set = s390_compat_regs_high_set,
1475	},
1476	{
1477		.core_note_type = NT_S390_GS_CB,
1478		.n = sizeof(struct gs_cb) / sizeof(__u64),
1479		.size = sizeof(__u64),
1480		.align = sizeof(__u64),
1481		.regset_get = s390_gs_cb_get,
1482		.set = s390_gs_cb_set,
1483	},
1484	{
1485		.core_note_type = NT_S390_GS_BC,
1486		.n = sizeof(struct gs_cb) / sizeof(__u64),
1487		.size = sizeof(__u64),
1488		.align = sizeof(__u64),
1489		.regset_get = s390_gs_bc_get,
1490		.set = s390_gs_bc_set,
1491	},
1492	{
1493		.core_note_type = NT_S390_RI_CB,
1494		.n = sizeof(struct runtime_instr_cb) / sizeof(__u64),
1495		.size = sizeof(__u64),
1496		.align = sizeof(__u64),
1497		.regset_get = s390_runtime_instr_get,
1498		.set = s390_runtime_instr_set,
1499	},
1500};
1501
1502static const struct user_regset_view user_s390_compat_view = {
1503	.name = "s390",
1504	.e_machine = EM_S390,
1505	.regsets = s390_compat_regsets,
1506	.n = ARRAY_SIZE(s390_compat_regsets)
1507};
1508#endif
1509
1510const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1511{
1512#ifdef CONFIG_COMPAT
1513	if (test_tsk_thread_flag(task, TIF_31BIT))
1514		return &user_s390_compat_view;
1515#endif
1516	return &user_s390_view;
1517}
1518
1519static const char *gpr_names[NUM_GPRS] = {
1520	"r0", "r1",  "r2",  "r3",  "r4",  "r5",  "r6",  "r7",
1521	"r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
1522};
1523
1524unsigned long regs_get_register(struct pt_regs *regs, unsigned int offset)
1525{
1526	if (offset >= NUM_GPRS)
1527		return 0;
1528	return regs->gprs[offset];
1529}
1530
1531int regs_query_register_offset(const char *name)
1532{
1533	unsigned long offset;
1534
1535	if (!name || *name != 'r')
1536		return -EINVAL;
1537	if (kstrtoul(name + 1, 10, &offset))
1538		return -EINVAL;
1539	if (offset >= NUM_GPRS)
1540		return -EINVAL;
1541	return offset;
1542}
1543
1544const char *regs_query_register_name(unsigned int offset)
1545{
1546	if (offset >= NUM_GPRS)
1547		return NULL;
1548	return gpr_names[offset];
1549}
1550
1551static int regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
1552{
1553	unsigned long ksp = kernel_stack_pointer(regs);
1554
1555	return (addr & ~(THREAD_SIZE - 1)) == (ksp & ~(THREAD_SIZE - 1));
1556}
1557
1558/**
1559 * regs_get_kernel_stack_nth() - get Nth entry of the stack
1560 * @regs:pt_regs which contains kernel stack pointer.
1561 * @n:stack entry number.
1562 *
1563 * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
1564 * is specifined by @regs. If the @n th entry is NOT in the kernel stack,
1565 * this returns 0.
1566 */
1567unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
1568{
1569	unsigned long addr;
1570
1571	addr = kernel_stack_pointer(regs) + n * sizeof(long);
1572	if (!regs_within_kernel_stack(regs, addr))
1573		return 0;
1574	return *(unsigned long *)addr;
1575}
1576