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v3.5.6
  1/*
  2 * unaligned.c: Unaligned load/store trap handling with special
  3 *              cases for the kernel to do them more quickly.
  4 *
  5 * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
  6 * Copyright (C) 1996 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
  7 */
  8
  9
 10#include <linux/kernel.h>
 11#include <linux/sched.h>
 12#include <linux/mm.h>
 13#include <asm/ptrace.h>
 14#include <asm/processor.h>
 15#include <asm/uaccess.h>
 16#include <linux/smp.h>
 17#include <linux/perf_event.h>
 18
 
 
 
 
 19enum direction {
 20	load,    /* ld, ldd, ldh, ldsh */
 21	store,   /* st, std, sth, stsh */
 22	both,    /* Swap, ldstub, etc. */
 23	fpload,
 24	fpstore,
 25	invalid,
 26};
 27
 28static inline enum direction decode_direction(unsigned int insn)
 29{
 30	unsigned long tmp = (insn >> 21) & 1;
 31
 32	if(!tmp)
 33		return load;
 34	else {
 35		if(((insn>>19)&0x3f) == 15)
 36			return both;
 37		else
 38			return store;
 39	}
 40}
 41
 42/* 8 = double-word, 4 = word, 2 = half-word */
 43static inline int decode_access_size(unsigned int insn)
 44{
 45	insn = (insn >> 19) & 3;
 46
 47	if(!insn)
 48		return 4;
 49	else if(insn == 3)
 50		return 8;
 51	else if(insn == 2)
 52		return 2;
 53	else {
 54		printk("Impossible unaligned trap. insn=%08x\n", insn);
 55		die_if_kernel("Byte sized unaligned access?!?!", current->thread.kregs);
 56		return 4; /* just to keep gcc happy. */
 57	}
 58}
 59
 60/* 0x400000 = signed, 0 = unsigned */
 61static inline int decode_signedness(unsigned int insn)
 62{
 63	return (insn & 0x400000);
 64}
 65
 66static inline void maybe_flush_windows(unsigned int rs1, unsigned int rs2,
 67				       unsigned int rd)
 68{
 69	if(rs2 >= 16 || rs1 >= 16 || rd >= 16) {
 70		/* Wheee... */
 71		__asm__ __volatile__("save %sp, -0x40, %sp\n\t"
 72				     "save %sp, -0x40, %sp\n\t"
 73				     "save %sp, -0x40, %sp\n\t"
 74				     "save %sp, -0x40, %sp\n\t"
 75				     "save %sp, -0x40, %sp\n\t"
 76				     "save %sp, -0x40, %sp\n\t"
 77				     "save %sp, -0x40, %sp\n\t"
 78				     "restore; restore; restore; restore;\n\t"
 79				     "restore; restore; restore;\n\t");
 80	}
 81}
 82
 83static inline int sign_extend_imm13(int imm)
 84{
 85	return imm << 19 >> 19;
 86}
 87
 88static inline unsigned long fetch_reg(unsigned int reg, struct pt_regs *regs)
 89{
 90	struct reg_window32 *win;
 91
 92	if(reg < 16)
 93		return (!reg ? 0 : regs->u_regs[reg]);
 94
 95	/* Ho hum, the slightly complicated case. */
 96	win = (struct reg_window32 *) regs->u_regs[UREG_FP];
 97	return win->locals[reg - 16]; /* yes, I know what this does... */
 98}
 99
100static inline unsigned long safe_fetch_reg(unsigned int reg, struct pt_regs *regs)
101{
102	struct reg_window32 __user *win;
103	unsigned long ret;
104
105	if (reg < 16)
106		return (!reg ? 0 : regs->u_regs[reg]);
107
108	/* Ho hum, the slightly complicated case. */
109	win = (struct reg_window32 __user *) regs->u_regs[UREG_FP];
110
111	if ((unsigned long)win & 3)
112		return -1;
113
114	if (get_user(ret, &win->locals[reg - 16]))
115		return -1;
116
117	return ret;
118}
119
120static inline unsigned long *fetch_reg_addr(unsigned int reg, struct pt_regs *regs)
121{
122	struct reg_window32 *win;
123
124	if(reg < 16)
125		return &regs->u_regs[reg];
126	win = (struct reg_window32 *) regs->u_regs[UREG_FP];
127	return &win->locals[reg - 16];
128}
129
130static unsigned long compute_effective_address(struct pt_regs *regs,
131					       unsigned int insn)
132{
133	unsigned int rs1 = (insn >> 14) & 0x1f;
134	unsigned int rs2 = insn & 0x1f;
135	unsigned int rd = (insn >> 25) & 0x1f;
136
137	if(insn & 0x2000) {
138		maybe_flush_windows(rs1, 0, rd);
139		return (fetch_reg(rs1, regs) + sign_extend_imm13(insn));
140	} else {
141		maybe_flush_windows(rs1, rs2, rd);
142		return (fetch_reg(rs1, regs) + fetch_reg(rs2, regs));
143	}
144}
145
146unsigned long safe_compute_effective_address(struct pt_regs *regs,
147					     unsigned int insn)
148{
149	unsigned int rs1 = (insn >> 14) & 0x1f;
150	unsigned int rs2 = insn & 0x1f;
151	unsigned int rd = (insn >> 25) & 0x1f;
152
153	if(insn & 0x2000) {
154		maybe_flush_windows(rs1, 0, rd);
155		return (safe_fetch_reg(rs1, regs) + sign_extend_imm13(insn));
156	} else {
157		maybe_flush_windows(rs1, rs2, rd);
158		return (safe_fetch_reg(rs1, regs) + safe_fetch_reg(rs2, regs));
159	}
160}
161
162/* This is just to make gcc think panic does return... */
163static void unaligned_panic(char *str)
164{
165	panic(str);
166}
167
168/* una_asm.S */
169extern int do_int_load(unsigned long *dest_reg, int size,
170		       unsigned long *saddr, int is_signed);
171extern int __do_int_store(unsigned long *dst_addr, int size,
172			  unsigned long *src_val);
173
174static int do_int_store(int reg_num, int size, unsigned long *dst_addr,
175			struct pt_regs *regs)
176{
177	unsigned long zero[2] = { 0, 0 };
178	unsigned long *src_val;
179
180	if (reg_num)
181		src_val = fetch_reg_addr(reg_num, regs);
182	else {
183		src_val = &zero[0];
184		if (size == 8)
185			zero[1] = fetch_reg(1, regs);
186	}
187	return __do_int_store(dst_addr, size, src_val);
188}
189
190extern void smp_capture(void);
191extern void smp_release(void);
192
193static inline void advance(struct pt_regs *regs)
194{
195	regs->pc   = regs->npc;
196	regs->npc += 4;
197}
198
199static inline int floating_point_load_or_store_p(unsigned int insn)
200{
201	return (insn >> 24) & 1;
202}
203
204static inline int ok_for_kernel(unsigned int insn)
205{
206	return !floating_point_load_or_store_p(insn);
207}
208
209static void kernel_mna_trap_fault(struct pt_regs *regs, unsigned int insn)
210{
211	unsigned long g2 = regs->u_regs [UREG_G2];
212	unsigned long fixup = search_extables_range(regs->pc, &g2);
213
214	if (!fixup) {
215		unsigned long address = compute_effective_address(regs, insn);
216        	if(address < PAGE_SIZE) {
217                	printk(KERN_ALERT "Unable to handle kernel NULL pointer dereference in mna handler");
218        	} else
219                	printk(KERN_ALERT "Unable to handle kernel paging request in mna handler");
220	        printk(KERN_ALERT " at virtual address %08lx\n",address);
221		printk(KERN_ALERT "current->{mm,active_mm}->context = %08lx\n",
222			(current->mm ? current->mm->context :
223			current->active_mm->context));
224		printk(KERN_ALERT "current->{mm,active_mm}->pgd = %08lx\n",
225			(current->mm ? (unsigned long) current->mm->pgd :
226			(unsigned long) current->active_mm->pgd));
227	        die_if_kernel("Oops", regs);
228		/* Not reached */
229	}
230	regs->pc = fixup;
231	regs->npc = regs->pc + 4;
232	regs->u_regs [UREG_G2] = g2;
233}
234
235asmlinkage void kernel_unaligned_trap(struct pt_regs *regs, unsigned int insn)
236{
237	enum direction dir = decode_direction(insn);
238	int size = decode_access_size(insn);
239
240	if(!ok_for_kernel(insn) || dir == both) {
241		printk("Unsupported unaligned load/store trap for kernel at <%08lx>.\n",
242		       regs->pc);
243		unaligned_panic("Wheee. Kernel does fpu/atomic unaligned load/store.");
244	} else {
245		unsigned long addr = compute_effective_address(regs, insn);
246		int err;
247
248		perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1, regs, addr);
249		switch (dir) {
250		case load:
251			err = do_int_load(fetch_reg_addr(((insn>>25)&0x1f),
252							 regs),
253					  size, (unsigned long *) addr,
254					  decode_signedness(insn));
255			break;
256
257		case store:
258			err = do_int_store(((insn>>25)&0x1f), size,
259					   (unsigned long *) addr, regs);
260			break;
261		default:
262			panic("Impossible kernel unaligned trap.");
263			/* Not reached... */
264		}
265		if (err)
266			kernel_mna_trap_fault(regs, insn);
267		else
268			advance(regs);
269	}
270}
271
272static inline int ok_for_user(struct pt_regs *regs, unsigned int insn,
273			      enum direction dir)
274{
275	unsigned int reg;
276	int check = (dir == load) ? VERIFY_READ : VERIFY_WRITE;
277	int size = ((insn >> 19) & 3) == 3 ? 8 : 4;
278
279	if ((regs->pc | regs->npc) & 3)
280		return 0;
281
282	/* Must access_ok() in all the necessary places. */
283#define WINREG_ADDR(regnum) \
284	((void __user *)(((unsigned long *)regs->u_regs[UREG_FP])+(regnum)))
285
286	reg = (insn >> 25) & 0x1f;
287	if (reg >= 16) {
288		if (!access_ok(check, WINREG_ADDR(reg - 16), size))
289			return -EFAULT;
290	}
291	reg = (insn >> 14) & 0x1f;
292	if (reg >= 16) {
293		if (!access_ok(check, WINREG_ADDR(reg - 16), size))
294			return -EFAULT;
295	}
296	if (!(insn & 0x2000)) {
297		reg = (insn & 0x1f);
298		if (reg >= 16) {
299			if (!access_ok(check, WINREG_ADDR(reg - 16), size))
300				return -EFAULT;
301		}
302	}
303#undef WINREG_ADDR
304	return 0;
305}
306
307static void user_mna_trap_fault(struct pt_regs *regs, unsigned int insn)
308{
309	siginfo_t info;
310
311	info.si_signo = SIGBUS;
312	info.si_errno = 0;
313	info.si_code = BUS_ADRALN;
314	info.si_addr = (void __user *)safe_compute_effective_address(regs, insn);
315	info.si_trapno = 0;
316	send_sig_info(SIGBUS, &info, current);
317}
318
319asmlinkage void user_unaligned_trap(struct pt_regs *regs, unsigned int insn)
320{
321	enum direction dir;
322
323	if(!(current->thread.flags & SPARC_FLAG_UNALIGNED) ||
324	   (((insn >> 30) & 3) != 3))
325		goto kill_user;
326	dir = decode_direction(insn);
327	if(!ok_for_user(regs, insn, dir)) {
328		goto kill_user;
329	} else {
330		int err, size = decode_access_size(insn);
331		unsigned long addr;
332
333		if(floating_point_load_or_store_p(insn)) {
334			printk("User FPU load/store unaligned unsupported.\n");
335			goto kill_user;
336		}
337
338		addr = compute_effective_address(regs, insn);
339		perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1, regs, addr);
340		switch(dir) {
341		case load:
342			err = do_int_load(fetch_reg_addr(((insn>>25)&0x1f),
343							 regs),
344					  size, (unsigned long *) addr,
345					  decode_signedness(insn));
346			break;
347
348		case store:
349			err = do_int_store(((insn>>25)&0x1f), size,
350					   (unsigned long *) addr, regs);
351			break;
352
353		case both:
354			/*
355			 * This was supported in 2.4. However, we question
356			 * the value of SWAP instruction across word boundaries.
357			 */
358			printk("Unaligned SWAP unsupported.\n");
359			err = -EFAULT;
360			break;
361
362		default:
363			unaligned_panic("Impossible user unaligned trap.");
364			goto out;
365		}
366		if (err)
367			goto kill_user;
368		else
369			advance(regs);
370		goto out;
371	}
372
373kill_user:
374	user_mna_trap_fault(regs, insn);
375out:
376	;
377}
v4.10.11
  1/*
  2 * unaligned.c: Unaligned load/store trap handling with special
  3 *              cases for the kernel to do them more quickly.
  4 *
  5 * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
  6 * Copyright (C) 1996 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
  7 */
  8
  9
 10#include <linux/kernel.h>
 11#include <linux/sched.h>
 12#include <linux/mm.h>
 13#include <asm/ptrace.h>
 14#include <asm/processor.h>
 15#include <linux/uaccess.h>
 16#include <linux/smp.h>
 17#include <linux/perf_event.h>
 18
 19#include <asm/setup.h>
 20
 21#include "kernel.h"
 22
 23enum direction {
 24	load,    /* ld, ldd, ldh, ldsh */
 25	store,   /* st, std, sth, stsh */
 26	both,    /* Swap, ldstub, etc. */
 27	fpload,
 28	fpstore,
 29	invalid,
 30};
 31
 32static inline enum direction decode_direction(unsigned int insn)
 33{
 34	unsigned long tmp = (insn >> 21) & 1;
 35
 36	if(!tmp)
 37		return load;
 38	else {
 39		if(((insn>>19)&0x3f) == 15)
 40			return both;
 41		else
 42			return store;
 43	}
 44}
 45
 46/* 8 = double-word, 4 = word, 2 = half-word */
 47static inline int decode_access_size(unsigned int insn)
 48{
 49	insn = (insn >> 19) & 3;
 50
 51	if(!insn)
 52		return 4;
 53	else if(insn == 3)
 54		return 8;
 55	else if(insn == 2)
 56		return 2;
 57	else {
 58		printk("Impossible unaligned trap. insn=%08x\n", insn);
 59		die_if_kernel("Byte sized unaligned access?!?!", current->thread.kregs);
 60		return 4; /* just to keep gcc happy. */
 61	}
 62}
 63
 64/* 0x400000 = signed, 0 = unsigned */
 65static inline int decode_signedness(unsigned int insn)
 66{
 67	return (insn & 0x400000);
 68}
 69
 70static inline void maybe_flush_windows(unsigned int rs1, unsigned int rs2,
 71				       unsigned int rd)
 72{
 73	if(rs2 >= 16 || rs1 >= 16 || rd >= 16) {
 74		/* Wheee... */
 75		__asm__ __volatile__("save %sp, -0x40, %sp\n\t"
 76				     "save %sp, -0x40, %sp\n\t"
 77				     "save %sp, -0x40, %sp\n\t"
 78				     "save %sp, -0x40, %sp\n\t"
 79				     "save %sp, -0x40, %sp\n\t"
 80				     "save %sp, -0x40, %sp\n\t"
 81				     "save %sp, -0x40, %sp\n\t"
 82				     "restore; restore; restore; restore;\n\t"
 83				     "restore; restore; restore;\n\t");
 84	}
 85}
 86
 87static inline int sign_extend_imm13(int imm)
 88{
 89	return imm << 19 >> 19;
 90}
 91
 92static inline unsigned long fetch_reg(unsigned int reg, struct pt_regs *regs)
 93{
 94	struct reg_window32 *win;
 95
 96	if(reg < 16)
 97		return (!reg ? 0 : regs->u_regs[reg]);
 98
 99	/* Ho hum, the slightly complicated case. */
100	win = (struct reg_window32 *) regs->u_regs[UREG_FP];
101	return win->locals[reg - 16]; /* yes, I know what this does... */
102}
103
104static inline unsigned long safe_fetch_reg(unsigned int reg, struct pt_regs *regs)
105{
106	struct reg_window32 __user *win;
107	unsigned long ret;
108
109	if (reg < 16)
110		return (!reg ? 0 : regs->u_regs[reg]);
111
112	/* Ho hum, the slightly complicated case. */
113	win = (struct reg_window32 __user *) regs->u_regs[UREG_FP];
114
115	if ((unsigned long)win & 3)
116		return -1;
117
118	if (get_user(ret, &win->locals[reg - 16]))
119		return -1;
120
121	return ret;
122}
123
124static inline unsigned long *fetch_reg_addr(unsigned int reg, struct pt_regs *regs)
125{
126	struct reg_window32 *win;
127
128	if(reg < 16)
129		return &regs->u_regs[reg];
130	win = (struct reg_window32 *) regs->u_regs[UREG_FP];
131	return &win->locals[reg - 16];
132}
133
134static unsigned long compute_effective_address(struct pt_regs *regs,
135					       unsigned int insn)
136{
137	unsigned int rs1 = (insn >> 14) & 0x1f;
138	unsigned int rs2 = insn & 0x1f;
139	unsigned int rd = (insn >> 25) & 0x1f;
140
141	if(insn & 0x2000) {
142		maybe_flush_windows(rs1, 0, rd);
143		return (fetch_reg(rs1, regs) + sign_extend_imm13(insn));
144	} else {
145		maybe_flush_windows(rs1, rs2, rd);
146		return (fetch_reg(rs1, regs) + fetch_reg(rs2, regs));
147	}
148}
149
150unsigned long safe_compute_effective_address(struct pt_regs *regs,
151					     unsigned int insn)
152{
153	unsigned int rs1 = (insn >> 14) & 0x1f;
154	unsigned int rs2 = insn & 0x1f;
155	unsigned int rd = (insn >> 25) & 0x1f;
156
157	if(insn & 0x2000) {
158		maybe_flush_windows(rs1, 0, rd);
159		return (safe_fetch_reg(rs1, regs) + sign_extend_imm13(insn));
160	} else {
161		maybe_flush_windows(rs1, rs2, rd);
162		return (safe_fetch_reg(rs1, regs) + safe_fetch_reg(rs2, regs));
163	}
164}
165
166/* This is just to make gcc think panic does return... */
167static void unaligned_panic(char *str)
168{
169	panic("%s", str);
170}
171
172/* una_asm.S */
173extern int do_int_load(unsigned long *dest_reg, int size,
174		       unsigned long *saddr, int is_signed);
175extern int __do_int_store(unsigned long *dst_addr, int size,
176			  unsigned long *src_val);
177
178static int do_int_store(int reg_num, int size, unsigned long *dst_addr,
179			struct pt_regs *regs)
180{
181	unsigned long zero[2] = { 0, 0 };
182	unsigned long *src_val;
183
184	if (reg_num)
185		src_val = fetch_reg_addr(reg_num, regs);
186	else {
187		src_val = &zero[0];
188		if (size == 8)
189			zero[1] = fetch_reg(1, regs);
190	}
191	return __do_int_store(dst_addr, size, src_val);
192}
193
194extern void smp_capture(void);
195extern void smp_release(void);
196
197static inline void advance(struct pt_regs *regs)
198{
199	regs->pc   = regs->npc;
200	regs->npc += 4;
201}
202
203static inline int floating_point_load_or_store_p(unsigned int insn)
204{
205	return (insn >> 24) & 1;
206}
207
208static inline int ok_for_kernel(unsigned int insn)
209{
210	return !floating_point_load_or_store_p(insn);
211}
212
213static void kernel_mna_trap_fault(struct pt_regs *regs, unsigned int insn)
214{
215	unsigned long g2 = regs->u_regs [UREG_G2];
216	unsigned long fixup = search_extables_range(regs->pc, &g2);
217
218	if (!fixup) {
219		unsigned long address = compute_effective_address(regs, insn);
220        	if(address < PAGE_SIZE) {
221                	printk(KERN_ALERT "Unable to handle kernel NULL pointer dereference in mna handler");
222        	} else
223                	printk(KERN_ALERT "Unable to handle kernel paging request in mna handler");
224	        printk(KERN_ALERT " at virtual address %08lx\n",address);
225		printk(KERN_ALERT "current->{mm,active_mm}->context = %08lx\n",
226			(current->mm ? current->mm->context :
227			current->active_mm->context));
228		printk(KERN_ALERT "current->{mm,active_mm}->pgd = %08lx\n",
229			(current->mm ? (unsigned long) current->mm->pgd :
230			(unsigned long) current->active_mm->pgd));
231	        die_if_kernel("Oops", regs);
232		/* Not reached */
233	}
234	regs->pc = fixup;
235	regs->npc = regs->pc + 4;
236	regs->u_regs [UREG_G2] = g2;
237}
238
239asmlinkage void kernel_unaligned_trap(struct pt_regs *regs, unsigned int insn)
240{
241	enum direction dir = decode_direction(insn);
242	int size = decode_access_size(insn);
243
244	if(!ok_for_kernel(insn) || dir == both) {
245		printk("Unsupported unaligned load/store trap for kernel at <%08lx>.\n",
246		       regs->pc);
247		unaligned_panic("Wheee. Kernel does fpu/atomic unaligned load/store.");
248	} else {
249		unsigned long addr = compute_effective_address(regs, insn);
250		int err;
251
252		perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1, regs, addr);
253		switch (dir) {
254		case load:
255			err = do_int_load(fetch_reg_addr(((insn>>25)&0x1f),
256							 regs),
257					  size, (unsigned long *) addr,
258					  decode_signedness(insn));
259			break;
260
261		case store:
262			err = do_int_store(((insn>>25)&0x1f), size,
263					   (unsigned long *) addr, regs);
264			break;
265		default:
266			panic("Impossible kernel unaligned trap.");
267			/* Not reached... */
268		}
269		if (err)
270			kernel_mna_trap_fault(regs, insn);
271		else
272			advance(regs);
273	}
274}
275
276static inline int ok_for_user(struct pt_regs *regs, unsigned int insn,
277			      enum direction dir)
278{
279	unsigned int reg;
280	int check = (dir == load) ? VERIFY_READ : VERIFY_WRITE;
281	int size = ((insn >> 19) & 3) == 3 ? 8 : 4;
282
283	if ((regs->pc | regs->npc) & 3)
284		return 0;
285
286	/* Must access_ok() in all the necessary places. */
287#define WINREG_ADDR(regnum) \
288	((void __user *)(((unsigned long *)regs->u_regs[UREG_FP])+(regnum)))
289
290	reg = (insn >> 25) & 0x1f;
291	if (reg >= 16) {
292		if (!access_ok(check, WINREG_ADDR(reg - 16), size))
293			return -EFAULT;
294	}
295	reg = (insn >> 14) & 0x1f;
296	if (reg >= 16) {
297		if (!access_ok(check, WINREG_ADDR(reg - 16), size))
298			return -EFAULT;
299	}
300	if (!(insn & 0x2000)) {
301		reg = (insn & 0x1f);
302		if (reg >= 16) {
303			if (!access_ok(check, WINREG_ADDR(reg - 16), size))
304				return -EFAULT;
305		}
306	}
307#undef WINREG_ADDR
308	return 0;
309}
310
311static void user_mna_trap_fault(struct pt_regs *regs, unsigned int insn)
312{
313	siginfo_t info;
314
315	info.si_signo = SIGBUS;
316	info.si_errno = 0;
317	info.si_code = BUS_ADRALN;
318	info.si_addr = (void __user *)safe_compute_effective_address(regs, insn);
319	info.si_trapno = 0;
320	send_sig_info(SIGBUS, &info, current);
321}
322
323asmlinkage void user_unaligned_trap(struct pt_regs *regs, unsigned int insn)
324{
325	enum direction dir;
326
327	if(!(current->thread.flags & SPARC_FLAG_UNALIGNED) ||
328	   (((insn >> 30) & 3) != 3))
329		goto kill_user;
330	dir = decode_direction(insn);
331	if(!ok_for_user(regs, insn, dir)) {
332		goto kill_user;
333	} else {
334		int err, size = decode_access_size(insn);
335		unsigned long addr;
336
337		if(floating_point_load_or_store_p(insn)) {
338			printk("User FPU load/store unaligned unsupported.\n");
339			goto kill_user;
340		}
341
342		addr = compute_effective_address(regs, insn);
343		perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1, regs, addr);
344		switch(dir) {
345		case load:
346			err = do_int_load(fetch_reg_addr(((insn>>25)&0x1f),
347							 regs),
348					  size, (unsigned long *) addr,
349					  decode_signedness(insn));
350			break;
351
352		case store:
353			err = do_int_store(((insn>>25)&0x1f), size,
354					   (unsigned long *) addr, regs);
355			break;
356
357		case both:
358			/*
359			 * This was supported in 2.4. However, we question
360			 * the value of SWAP instruction across word boundaries.
361			 */
362			printk("Unaligned SWAP unsupported.\n");
363			err = -EFAULT;
364			break;
365
366		default:
367			unaligned_panic("Impossible user unaligned trap.");
368			goto out;
369		}
370		if (err)
371			goto kill_user;
372		else
373			advance(regs);
374		goto out;
375	}
376
377kill_user:
378	user_mna_trap_fault(regs, insn);
379out:
380	;
381}