xref: /openbmc/linux/arch/ia64/kernel/entry.S (revision 87c2ce3b)
1/*
2 * ia64/kernel/entry.S
3 *
4 * Kernel entry points.
5 *
6 * Copyright (C) 1998-2003, 2005 Hewlett-Packard Co
7 *	David Mosberger-Tang <davidm@hpl.hp.com>
8 * Copyright (C) 1999, 2002-2003
9 *	Asit Mallick <Asit.K.Mallick@intel.com>
10 * 	Don Dugger <Don.Dugger@intel.com>
11 *	Suresh Siddha <suresh.b.siddha@intel.com>
12 *	Fenghua Yu <fenghua.yu@intel.com>
13 * Copyright (C) 1999 VA Linux Systems
14 * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
15 */
16/*
17 * ia64_switch_to now places correct virtual mapping in in TR2 for
18 * kernel stack. This allows us to handle interrupts without changing
19 * to physical mode.
20 *
21 * Jonathan Nicklin	<nicklin@missioncriticallinux.com>
22 * Patrick O'Rourke	<orourke@missioncriticallinux.com>
23 * 11/07/2000
24 */
25/*
26 * Global (preserved) predicate usage on syscall entry/exit path:
27 *
28 *	pKStk:		See entry.h.
29 *	pUStk:		See entry.h.
30 *	pSys:		See entry.h.
31 *	pNonSys:	!pSys
32 */
33
34#include <linux/config.h>
35
36#include <asm/asmmacro.h>
37#include <asm/cache.h>
38#include <asm/errno.h>
39#include <asm/kregs.h>
40#include <asm/asm-offsets.h>
41#include <asm/pgtable.h>
42#include <asm/percpu.h>
43#include <asm/processor.h>
44#include <asm/thread_info.h>
45#include <asm/unistd.h>
46
47#include "minstate.h"
48
49	/*
50	 * execve() is special because in case of success, we need to
51	 * setup a null register window frame.
52	 */
53ENTRY(ia64_execve)
54	/*
55	 * Allocate 8 input registers since ptrace() may clobber them
56	 */
57	.prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(8)
58	alloc loc1=ar.pfs,8,2,4,0
59	mov loc0=rp
60	.body
61	mov out0=in0			// filename
62	;;				// stop bit between alloc and call
63	mov out1=in1			// argv
64	mov out2=in2			// envp
65	add out3=16,sp			// regs
66	br.call.sptk.many rp=sys_execve
67.ret0:
68#ifdef CONFIG_IA32_SUPPORT
69	/*
70	 * Check if we're returning to ia32 mode. If so, we need to restore ia32 registers
71	 * from pt_regs.
72	 */
73	adds r16=PT(CR_IPSR)+16,sp
74	;;
75	ld8 r16=[r16]
76#endif
77	cmp4.ge p6,p7=r8,r0
78	mov ar.pfs=loc1			// restore ar.pfs
79	sxt4 r8=r8			// return 64-bit result
80	;;
81	stf.spill [sp]=f0
82(p6)	cmp.ne pKStk,pUStk=r0,r0	// a successful execve() lands us in user-mode...
83	mov rp=loc0
84(p6)	mov ar.pfs=r0			// clear ar.pfs on success
85(p7)	br.ret.sptk.many rp
86
87	/*
88	 * In theory, we'd have to zap this state only to prevent leaking of
89	 * security sensitive state (e.g., if current->mm->dumpable is zero).  However,
90	 * this executes in less than 20 cycles even on Itanium, so it's not worth
91	 * optimizing for...).
92	 */
93	mov ar.unat=0; 		mov ar.lc=0
94	mov r4=0;		mov f2=f0;		mov b1=r0
95	mov r5=0;		mov f3=f0;		mov b2=r0
96	mov r6=0;		mov f4=f0;		mov b3=r0
97	mov r7=0;		mov f5=f0;		mov b4=r0
98	ldf.fill f12=[sp];	mov f13=f0;		mov b5=r0
99	ldf.fill f14=[sp];	ldf.fill f15=[sp];	mov f16=f0
100	ldf.fill f17=[sp];	ldf.fill f18=[sp];	mov f19=f0
101	ldf.fill f20=[sp];	ldf.fill f21=[sp];	mov f22=f0
102	ldf.fill f23=[sp];	ldf.fill f24=[sp];	mov f25=f0
103	ldf.fill f26=[sp];	ldf.fill f27=[sp];	mov f28=f0
104	ldf.fill f29=[sp];	ldf.fill f30=[sp];	mov f31=f0
105#ifdef CONFIG_IA32_SUPPORT
106	tbit.nz p6,p0=r16, IA64_PSR_IS_BIT
107	movl loc0=ia64_ret_from_ia32_execve
108	;;
109(p6)	mov rp=loc0
110#endif
111	br.ret.sptk.many rp
112END(ia64_execve)
113
114/*
115 * sys_clone2(u64 flags, u64 ustack_base, u64 ustack_size, u64 parent_tidptr, u64 child_tidptr,
116 *	      u64 tls)
117 */
118GLOBAL_ENTRY(sys_clone2)
119	/*
120	 * Allocate 8 input registers since ptrace() may clobber them
121	 */
122	.prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(8)
123	alloc r16=ar.pfs,8,2,6,0
124	DO_SAVE_SWITCH_STACK
125	adds r2=PT(R16)+IA64_SWITCH_STACK_SIZE+16,sp
126	mov loc0=rp
127	mov loc1=r16				// save ar.pfs across do_fork
128	.body
129	mov out1=in1
130	mov out3=in2
131	tbit.nz p6,p0=in0,CLONE_SETTLS_BIT
132	mov out4=in3	// parent_tidptr: valid only w/CLONE_PARENT_SETTID
133	;;
134(p6)	st8 [r2]=in5				// store TLS in r16 for copy_thread()
135	mov out5=in4	// child_tidptr:  valid only w/CLONE_CHILD_SETTID or CLONE_CHILD_CLEARTID
136	adds out2=IA64_SWITCH_STACK_SIZE+16,sp	// out2 = &regs
137	mov out0=in0				// out0 = clone_flags
138	br.call.sptk.many rp=do_fork
139.ret1:	.restore sp
140	adds sp=IA64_SWITCH_STACK_SIZE,sp	// pop the switch stack
141	mov ar.pfs=loc1
142	mov rp=loc0
143	br.ret.sptk.many rp
144END(sys_clone2)
145
146/*
147 * sys_clone(u64 flags, u64 ustack_base, u64 parent_tidptr, u64 child_tidptr, u64 tls)
148 *	Deprecated.  Use sys_clone2() instead.
149 */
150GLOBAL_ENTRY(sys_clone)
151	/*
152	 * Allocate 8 input registers since ptrace() may clobber them
153	 */
154	.prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(8)
155	alloc r16=ar.pfs,8,2,6,0
156	DO_SAVE_SWITCH_STACK
157	adds r2=PT(R16)+IA64_SWITCH_STACK_SIZE+16,sp
158	mov loc0=rp
159	mov loc1=r16				// save ar.pfs across do_fork
160	.body
161	mov out1=in1
162	mov out3=16				// stacksize (compensates for 16-byte scratch area)
163	tbit.nz p6,p0=in0,CLONE_SETTLS_BIT
164	mov out4=in2	// parent_tidptr: valid only w/CLONE_PARENT_SETTID
165	;;
166(p6)	st8 [r2]=in4				// store TLS in r13 (tp)
167	mov out5=in3	// child_tidptr:  valid only w/CLONE_CHILD_SETTID or CLONE_CHILD_CLEARTID
168	adds out2=IA64_SWITCH_STACK_SIZE+16,sp	// out2 = &regs
169	mov out0=in0				// out0 = clone_flags
170	br.call.sptk.many rp=do_fork
171.ret2:	.restore sp
172	adds sp=IA64_SWITCH_STACK_SIZE,sp	// pop the switch stack
173	mov ar.pfs=loc1
174	mov rp=loc0
175	br.ret.sptk.many rp
176END(sys_clone)
177
178/*
179 * prev_task <- ia64_switch_to(struct task_struct *next)
180 *	With Ingo's new scheduler, interrupts are disabled when this routine gets
181 *	called.  The code starting at .map relies on this.  The rest of the code
182 *	doesn't care about the interrupt masking status.
183 */
184GLOBAL_ENTRY(ia64_switch_to)
185	.prologue
186	alloc r16=ar.pfs,1,0,0,0
187	DO_SAVE_SWITCH_STACK
188	.body
189
190	adds r22=IA64_TASK_THREAD_KSP_OFFSET,r13
191	movl r25=init_task
192	mov r27=IA64_KR(CURRENT_STACK)
193	adds r21=IA64_TASK_THREAD_KSP_OFFSET,in0
194	dep r20=0,in0,61,3		// physical address of "next"
195	;;
196	st8 [r22]=sp			// save kernel stack pointer of old task
197	shr.u r26=r20,IA64_GRANULE_SHIFT
198	cmp.eq p7,p6=r25,in0
199	;;
200	/*
201	 * If we've already mapped this task's page, we can skip doing it again.
202	 */
203(p6)	cmp.eq p7,p6=r26,r27
204(p6)	br.cond.dpnt .map
205	;;
206.done:
207	ld8 sp=[r21]			// load kernel stack pointer of new task
208	mov IA64_KR(CURRENT)=in0	// update "current" application register
209	mov r8=r13			// return pointer to previously running task
210	mov r13=in0			// set "current" pointer
211	;;
212	DO_LOAD_SWITCH_STACK
213
214#ifdef CONFIG_SMP
215	sync.i				// ensure "fc"s done by this CPU are visible on other CPUs
216#endif
217	br.ret.sptk.many rp		// boogie on out in new context
218
219.map:
220	rsm psr.ic			// interrupts (psr.i) are already disabled here
221	movl r25=PAGE_KERNEL
222	;;
223	srlz.d
224	or r23=r25,r20			// construct PA | page properties
225	mov r25=IA64_GRANULE_SHIFT<<2
226	;;
227	mov cr.itir=r25
228	mov cr.ifa=in0			// VA of next task...
229	;;
230	mov r25=IA64_TR_CURRENT_STACK
231	mov IA64_KR(CURRENT_STACK)=r26	// remember last page we mapped...
232	;;
233	itr.d dtr[r25]=r23		// wire in new mapping...
234	ssm psr.ic			// reenable the psr.ic bit
235	;;
236	srlz.d
237	br.cond.sptk .done
238END(ia64_switch_to)
239
240/*
241 * Note that interrupts are enabled during save_switch_stack and load_switch_stack.  This
242 * means that we may get an interrupt with "sp" pointing to the new kernel stack while
243 * ar.bspstore is still pointing to the old kernel backing store area.  Since ar.rsc,
244 * ar.rnat, ar.bsp, and ar.bspstore are all preserved by interrupts, this is not a
245 * problem.  Also, we don't need to specify unwind information for preserved registers
246 * that are not modified in save_switch_stack as the right unwind information is already
247 * specified at the call-site of save_switch_stack.
248 */
249
250/*
251 * save_switch_stack:
252 *	- r16 holds ar.pfs
253 *	- b7 holds address to return to
254 *	- rp (b0) holds return address to save
255 */
256GLOBAL_ENTRY(save_switch_stack)
257	.prologue
258	.altrp b7
259	flushrs			// flush dirty regs to backing store (must be first in insn group)
260	.save @priunat,r17
261	mov r17=ar.unat		// preserve caller's
262	.body
263#ifdef CONFIG_ITANIUM
264	adds r2=16+128,sp
265	adds r3=16+64,sp
266	adds r14=SW(R4)+16,sp
267	;;
268	st8.spill [r14]=r4,16		// spill r4
269	lfetch.fault.excl.nt1 [r3],128
270	;;
271	lfetch.fault.excl.nt1 [r2],128
272	lfetch.fault.excl.nt1 [r3],128
273	;;
274	lfetch.fault.excl [r2]
275	lfetch.fault.excl [r3]
276	adds r15=SW(R5)+16,sp
277#else
278	add r2=16+3*128,sp
279	add r3=16,sp
280	add r14=SW(R4)+16,sp
281	;;
282	st8.spill [r14]=r4,SW(R6)-SW(R4)	// spill r4 and prefetch offset 0x1c0
283	lfetch.fault.excl.nt1 [r3],128	//		prefetch offset 0x010
284	;;
285	lfetch.fault.excl.nt1 [r3],128	//		prefetch offset 0x090
286	lfetch.fault.excl.nt1 [r2],128	//		prefetch offset 0x190
287	;;
288	lfetch.fault.excl.nt1 [r3]	//		prefetch offset 0x110
289	lfetch.fault.excl.nt1 [r2]	//		prefetch offset 0x210
290	adds r15=SW(R5)+16,sp
291#endif
292	;;
293	st8.spill [r15]=r5,SW(R7)-SW(R5)	// spill r5
294	mov.m ar.rsc=0			// put RSE in mode: enforced lazy, little endian, pl 0
295	add r2=SW(F2)+16,sp		// r2 = &sw->f2
296	;;
297	st8.spill [r14]=r6,SW(B0)-SW(R6)	// spill r6
298	mov.m r18=ar.fpsr		// preserve fpsr
299	add r3=SW(F3)+16,sp		// r3 = &sw->f3
300	;;
301	stf.spill [r2]=f2,32
302	mov.m r19=ar.rnat
303	mov r21=b0
304
305	stf.spill [r3]=f3,32
306	st8.spill [r15]=r7,SW(B2)-SW(R7)	// spill r7
307	mov r22=b1
308	;;
309	// since we're done with the spills, read and save ar.unat:
310	mov.m r29=ar.unat
311	mov.m r20=ar.bspstore
312	mov r23=b2
313	stf.spill [r2]=f4,32
314	stf.spill [r3]=f5,32
315	mov r24=b3
316	;;
317	st8 [r14]=r21,SW(B1)-SW(B0)		// save b0
318	st8 [r15]=r23,SW(B3)-SW(B2)		// save b2
319	mov r25=b4
320	mov r26=b5
321	;;
322	st8 [r14]=r22,SW(B4)-SW(B1)		// save b1
323	st8 [r15]=r24,SW(AR_PFS)-SW(B3)		// save b3
324	mov r21=ar.lc		// I-unit
325	stf.spill [r2]=f12,32
326	stf.spill [r3]=f13,32
327	;;
328	st8 [r14]=r25,SW(B5)-SW(B4)		// save b4
329	st8 [r15]=r16,SW(AR_LC)-SW(AR_PFS)	// save ar.pfs
330	stf.spill [r2]=f14,32
331	stf.spill [r3]=f15,32
332	;;
333	st8 [r14]=r26				// save b5
334	st8 [r15]=r21				// save ar.lc
335	stf.spill [r2]=f16,32
336	stf.spill [r3]=f17,32
337	;;
338	stf.spill [r2]=f18,32
339	stf.spill [r3]=f19,32
340	;;
341	stf.spill [r2]=f20,32
342	stf.spill [r3]=f21,32
343	;;
344	stf.spill [r2]=f22,32
345	stf.spill [r3]=f23,32
346	;;
347	stf.spill [r2]=f24,32
348	stf.spill [r3]=f25,32
349	;;
350	stf.spill [r2]=f26,32
351	stf.spill [r3]=f27,32
352	;;
353	stf.spill [r2]=f28,32
354	stf.spill [r3]=f29,32
355	;;
356	stf.spill [r2]=f30,SW(AR_UNAT)-SW(F30)
357	stf.spill [r3]=f31,SW(PR)-SW(F31)
358	add r14=SW(CALLER_UNAT)+16,sp
359	;;
360	st8 [r2]=r29,SW(AR_RNAT)-SW(AR_UNAT)	// save ar.unat
361	st8 [r14]=r17,SW(AR_FPSR)-SW(CALLER_UNAT) // save caller_unat
362	mov r21=pr
363	;;
364	st8 [r2]=r19,SW(AR_BSPSTORE)-SW(AR_RNAT) // save ar.rnat
365	st8 [r3]=r21				// save predicate registers
366	;;
367	st8 [r2]=r20				// save ar.bspstore
368	st8 [r14]=r18				// save fpsr
369	mov ar.rsc=3		// put RSE back into eager mode, pl 0
370	br.cond.sptk.many b7
371END(save_switch_stack)
372
373/*
374 * load_switch_stack:
375 *	- "invala" MUST be done at call site (normally in DO_LOAD_SWITCH_STACK)
376 *	- b7 holds address to return to
377 *	- must not touch r8-r11
378 */
379ENTRY(load_switch_stack)
380	.prologue
381	.altrp b7
382
383	.body
384	lfetch.fault.nt1 [sp]
385	adds r2=SW(AR_BSPSTORE)+16,sp
386	adds r3=SW(AR_UNAT)+16,sp
387	mov ar.rsc=0						// put RSE into enforced lazy mode
388	adds r14=SW(CALLER_UNAT)+16,sp
389	adds r15=SW(AR_FPSR)+16,sp
390	;;
391	ld8 r27=[r2],(SW(B0)-SW(AR_BSPSTORE))	// bspstore
392	ld8 r29=[r3],(SW(B1)-SW(AR_UNAT))	// unat
393	;;
394	ld8 r21=[r2],16		// restore b0
395	ld8 r22=[r3],16		// restore b1
396	;;
397	ld8 r23=[r2],16		// restore b2
398	ld8 r24=[r3],16		// restore b3
399	;;
400	ld8 r25=[r2],16		// restore b4
401	ld8 r26=[r3],16		// restore b5
402	;;
403	ld8 r16=[r2],(SW(PR)-SW(AR_PFS))	// ar.pfs
404	ld8 r17=[r3],(SW(AR_RNAT)-SW(AR_LC))	// ar.lc
405	;;
406	ld8 r28=[r2]		// restore pr
407	ld8 r30=[r3]		// restore rnat
408	;;
409	ld8 r18=[r14],16	// restore caller's unat
410	ld8 r19=[r15],24	// restore fpsr
411	;;
412	ldf.fill f2=[r14],32
413	ldf.fill f3=[r15],32
414	;;
415	ldf.fill f4=[r14],32
416	ldf.fill f5=[r15],32
417	;;
418	ldf.fill f12=[r14],32
419	ldf.fill f13=[r15],32
420	;;
421	ldf.fill f14=[r14],32
422	ldf.fill f15=[r15],32
423	;;
424	ldf.fill f16=[r14],32
425	ldf.fill f17=[r15],32
426	;;
427	ldf.fill f18=[r14],32
428	ldf.fill f19=[r15],32
429	mov b0=r21
430	;;
431	ldf.fill f20=[r14],32
432	ldf.fill f21=[r15],32
433	mov b1=r22
434	;;
435	ldf.fill f22=[r14],32
436	ldf.fill f23=[r15],32
437	mov b2=r23
438	;;
439	mov ar.bspstore=r27
440	mov ar.unat=r29		// establish unat holding the NaT bits for r4-r7
441	mov b3=r24
442	;;
443	ldf.fill f24=[r14],32
444	ldf.fill f25=[r15],32
445	mov b4=r25
446	;;
447	ldf.fill f26=[r14],32
448	ldf.fill f27=[r15],32
449	mov b5=r26
450	;;
451	ldf.fill f28=[r14],32
452	ldf.fill f29=[r15],32
453	mov ar.pfs=r16
454	;;
455	ldf.fill f30=[r14],32
456	ldf.fill f31=[r15],24
457	mov ar.lc=r17
458	;;
459	ld8.fill r4=[r14],16
460	ld8.fill r5=[r15],16
461	mov pr=r28,-1
462	;;
463	ld8.fill r6=[r14],16
464	ld8.fill r7=[r15],16
465
466	mov ar.unat=r18				// restore caller's unat
467	mov ar.rnat=r30				// must restore after bspstore but before rsc!
468	mov ar.fpsr=r19				// restore fpsr
469	mov ar.rsc=3				// put RSE back into eager mode, pl 0
470	br.cond.sptk.many b7
471END(load_switch_stack)
472
473GLOBAL_ENTRY(prefetch_stack)
474	add r14 = -IA64_SWITCH_STACK_SIZE, sp
475	add r15 = IA64_TASK_THREAD_KSP_OFFSET, in0
476	;;
477	ld8 r16 = [r15]				// load next's stack pointer
478	lfetch.fault.excl [r14], 128
479	;;
480	lfetch.fault.excl [r14], 128
481	lfetch.fault [r16], 128
482	;;
483	lfetch.fault.excl [r14], 128
484	lfetch.fault [r16], 128
485	;;
486	lfetch.fault.excl [r14], 128
487	lfetch.fault [r16], 128
488	;;
489	lfetch.fault.excl [r14], 128
490	lfetch.fault [r16], 128
491	;;
492	lfetch.fault [r16], 128
493	br.ret.sptk.many rp
494END(prefetch_stack)
495
496GLOBAL_ENTRY(execve)
497	mov r15=__NR_execve			// put syscall number in place
498	break __BREAK_SYSCALL
499	br.ret.sptk.many rp
500END(execve)
501
502GLOBAL_ENTRY(clone)
503	mov r15=__NR_clone			// put syscall number in place
504	break __BREAK_SYSCALL
505	br.ret.sptk.many rp
506END(clone)
507
508	/*
509	 * Invoke a system call, but do some tracing before and after the call.
510	 * We MUST preserve the current register frame throughout this routine
511	 * because some system calls (such as ia64_execve) directly
512	 * manipulate ar.pfs.
513	 */
514GLOBAL_ENTRY(ia64_trace_syscall)
515	PT_REGS_UNWIND_INFO(0)
516	/*
517	 * We need to preserve the scratch registers f6-f11 in case the system
518	 * call is sigreturn.
519	 */
520	adds r16=PT(F6)+16,sp
521	adds r17=PT(F7)+16,sp
522	;;
523 	stf.spill [r16]=f6,32
524 	stf.spill [r17]=f7,32
525	;;
526 	stf.spill [r16]=f8,32
527 	stf.spill [r17]=f9,32
528	;;
529 	stf.spill [r16]=f10
530 	stf.spill [r17]=f11
531	br.call.sptk.many rp=syscall_trace_enter // give parent a chance to catch syscall args
532	adds r16=PT(F6)+16,sp
533	adds r17=PT(F7)+16,sp
534	;;
535	ldf.fill f6=[r16],32
536	ldf.fill f7=[r17],32
537	;;
538	ldf.fill f8=[r16],32
539	ldf.fill f9=[r17],32
540	;;
541	ldf.fill f10=[r16]
542	ldf.fill f11=[r17]
543	// the syscall number may have changed, so re-load it and re-calculate the
544	// syscall entry-point:
545	adds r15=PT(R15)+16,sp			// r15 = &pt_regs.r15 (syscall #)
546	;;
547	ld8 r15=[r15]
548	mov r3=NR_syscalls - 1
549	;;
550	adds r15=-1024,r15
551	movl r16=sys_call_table
552	;;
553	shladd r20=r15,3,r16			// r20 = sys_call_table + 8*(syscall-1024)
554	cmp.leu p6,p7=r15,r3
555	;;
556(p6)	ld8 r20=[r20]				// load address of syscall entry point
557(p7)	movl r20=sys_ni_syscall
558	;;
559	mov b6=r20
560	br.call.sptk.many rp=b6			// do the syscall
561.strace_check_retval:
562	cmp.lt p6,p0=r8,r0			// syscall failed?
563	adds r2=PT(R8)+16,sp			// r2 = &pt_regs.r8
564	adds r3=PT(R10)+16,sp			// r3 = &pt_regs.r10
565	mov r10=0
566(p6)	br.cond.sptk strace_error		// syscall failed ->
567	;;					// avoid RAW on r10
568.strace_save_retval:
569.mem.offset 0,0; st8.spill [r2]=r8		// store return value in slot for r8
570.mem.offset 8,0; st8.spill [r3]=r10		// clear error indication in slot for r10
571	br.call.sptk.many rp=syscall_trace_leave // give parent a chance to catch return value
572.ret3:	br.cond.sptk .work_pending_syscall_end
573
574strace_error:
575	ld8 r3=[r2]				// load pt_regs.r8
576	sub r9=0,r8				// negate return value to get errno value
577	;;
578	cmp.ne p6,p0=r3,r0			// is pt_regs.r8!=0?
579	adds r3=16,r2				// r3=&pt_regs.r10
580	;;
581(p6)	mov r10=-1
582(p6)	mov r8=r9
583	br.cond.sptk .strace_save_retval
584END(ia64_trace_syscall)
585
586	/*
587	 * When traced and returning from sigreturn, we invoke syscall_trace but then
588	 * go straight to ia64_leave_kernel rather than ia64_leave_syscall.
589	 */
590GLOBAL_ENTRY(ia64_strace_leave_kernel)
591	PT_REGS_UNWIND_INFO(0)
592{	/*
593	 * Some versions of gas generate bad unwind info if the first instruction of a
594	 * procedure doesn't go into the first slot of a bundle.  This is a workaround.
595	 */
596	nop.m 0
597	nop.i 0
598	br.call.sptk.many rp=syscall_trace_leave // give parent a chance to catch return value
599}
600.ret4:	br.cond.sptk ia64_leave_kernel
601END(ia64_strace_leave_kernel)
602
603GLOBAL_ENTRY(ia64_ret_from_clone)
604	PT_REGS_UNWIND_INFO(0)
605{	/*
606	 * Some versions of gas generate bad unwind info if the first instruction of a
607	 * procedure doesn't go into the first slot of a bundle.  This is a workaround.
608	 */
609	nop.m 0
610	nop.i 0
611	/*
612	 * We need to call schedule_tail() to complete the scheduling process.
613	 * Called by ia64_switch_to() after do_fork()->copy_thread().  r8 contains the
614	 * address of the previously executing task.
615	 */
616	br.call.sptk.many rp=ia64_invoke_schedule_tail
617}
618.ret8:
619	adds r2=TI_FLAGS+IA64_TASK_SIZE,r13
620	;;
621	ld4 r2=[r2]
622	;;
623	mov r8=0
624	and r2=_TIF_SYSCALL_TRACEAUDIT,r2
625	;;
626	cmp.ne p6,p0=r2,r0
627(p6)	br.cond.spnt .strace_check_retval
628	;;					// added stop bits to prevent r8 dependency
629END(ia64_ret_from_clone)
630	// fall through
631GLOBAL_ENTRY(ia64_ret_from_syscall)
632	PT_REGS_UNWIND_INFO(0)
633	cmp.ge p6,p7=r8,r0			// syscall executed successfully?
634	adds r2=PT(R8)+16,sp			// r2 = &pt_regs.r8
635	mov r10=r0				// clear error indication in r10
636(p7)	br.cond.spnt handle_syscall_error	// handle potential syscall failure
637END(ia64_ret_from_syscall)
638	// fall through
639/*
640 * ia64_leave_syscall(): Same as ia64_leave_kernel, except that it doesn't
641 *	need to switch to bank 0 and doesn't restore the scratch registers.
642 *	To avoid leaking kernel bits, the scratch registers are set to
643 *	the following known-to-be-safe values:
644 *
645 *		  r1: restored (global pointer)
646 *		  r2: cleared
647 *		  r3: 1 (when returning to user-level)
648 *	      r8-r11: restored (syscall return value(s))
649 *		 r12: restored (user-level stack pointer)
650 *		 r13: restored (user-level thread pointer)
651 *		 r14: set to __kernel_syscall_via_epc
652 *		 r15: restored (syscall #)
653 *	     r16-r17: cleared
654 *		 r18: user-level b6
655 *		 r19: cleared
656 *		 r20: user-level ar.fpsr
657 *		 r21: user-level b0
658 *		 r22: cleared
659 *		 r23: user-level ar.bspstore
660 *		 r24: user-level ar.rnat
661 *		 r25: user-level ar.unat
662 *		 r26: user-level ar.pfs
663 *		 r27: user-level ar.rsc
664 *		 r28: user-level ip
665 *		 r29: user-level psr
666 *		 r30: user-level cfm
667 *		 r31: user-level pr
668 *	      f6-f11: cleared
669 *		  pr: restored (user-level pr)
670 *		  b0: restored (user-level rp)
671 *	          b6: restored
672 *		  b7: set to __kernel_syscall_via_epc
673 *	     ar.unat: restored (user-level ar.unat)
674 *	      ar.pfs: restored (user-level ar.pfs)
675 *	      ar.rsc: restored (user-level ar.rsc)
676 *	     ar.rnat: restored (user-level ar.rnat)
677 *	 ar.bspstore: restored (user-level ar.bspstore)
678 *	     ar.fpsr: restored (user-level ar.fpsr)
679 *	      ar.ccv: cleared
680 *	      ar.csd: cleared
681 *	      ar.ssd: cleared
682 */
683ENTRY(ia64_leave_syscall)
684	PT_REGS_UNWIND_INFO(0)
685	/*
686	 * work.need_resched etc. mustn't get changed by this CPU before it returns to
687	 * user- or fsys-mode, hence we disable interrupts early on.
688	 *
689	 * p6 controls whether current_thread_info()->flags needs to be check for
690	 * extra work.  We always check for extra work when returning to user-level.
691	 * With CONFIG_PREEMPT, we also check for extra work when the preempt_count
692	 * is 0.  After extra work processing has been completed, execution
693	 * resumes at .work_processed_syscall with p6 set to 1 if the extra-work-check
694	 * needs to be redone.
695	 */
696#ifdef CONFIG_PREEMPT
697	rsm psr.i				// disable interrupts
698	cmp.eq pLvSys,p0=r0,r0			// pLvSys=1: leave from syscall
699(pKStk) adds r20=TI_PRE_COUNT+IA64_TASK_SIZE,r13
700	;;
701	.pred.rel.mutex pUStk,pKStk
702(pKStk) ld4 r21=[r20]			// r21 <- preempt_count
703(pUStk)	mov r21=0			// r21 <- 0
704	;;
705	cmp.eq p6,p0=r21,r0		// p6 <- pUStk || (preempt_count == 0)
706#else /* !CONFIG_PREEMPT */
707(pUStk)	rsm psr.i
708	cmp.eq pLvSys,p0=r0,r0		// pLvSys=1: leave from syscall
709(pUStk)	cmp.eq.unc p6,p0=r0,r0		// p6 <- pUStk
710#endif
711.work_processed_syscall:
712	adds r2=PT(LOADRS)+16,r12
713	adds r3=PT(AR_BSPSTORE)+16,r12
714	adds r18=TI_FLAGS+IA64_TASK_SIZE,r13
715	;;
716(p6)	ld4 r31=[r18]				// load current_thread_info()->flags
717	ld8 r19=[r2],PT(B6)-PT(LOADRS)		// load ar.rsc value for "loadrs"
718	nop.i 0
719	;;
720	mov r16=ar.bsp				// M2  get existing backing store pointer
721	ld8 r18=[r2],PT(R9)-PT(B6)		// load b6
722(p6)	and r15=TIF_WORK_MASK,r31		// any work other than TIF_SYSCALL_TRACE?
723	;;
724	ld8 r23=[r3],PT(R11)-PT(AR_BSPSTORE)	// load ar.bspstore (may be garbage)
725(p6)	cmp4.ne.unc p6,p0=r15, r0		// any special work pending?
726(p6)	br.cond.spnt .work_pending_syscall
727	;;
728	// start restoring the state saved on the kernel stack (struct pt_regs):
729	ld8 r9=[r2],PT(CR_IPSR)-PT(R9)
730	ld8 r11=[r3],PT(CR_IIP)-PT(R11)
731(pNonSys) break 0		//      bug check: we shouldn't be here if pNonSys is TRUE!
732	;;
733	invala			// M0|1 invalidate ALAT
734	rsm psr.i | psr.ic	// M2   turn off interrupts and interruption collection
735	cmp.eq p9,p0=r0,r0	// A    set p9 to indicate that we should restore cr.ifs
736
737	ld8 r29=[r2],16		// M0|1 load cr.ipsr
738	ld8 r28=[r3],16		// M0|1 load cr.iip
739	mov r22=r0		// A    clear r22
740	;;
741	ld8 r30=[r2],16		// M0|1 load cr.ifs
742	ld8 r25=[r3],16		// M0|1 load ar.unat
743(pUStk) add r14=IA64_TASK_THREAD_ON_USTACK_OFFSET,r13
744	;;
745	ld8 r26=[r2],PT(B0)-PT(AR_PFS)	// M0|1 load ar.pfs
746(pKStk)	mov r22=psr			// M2   read PSR now that interrupts are disabled
747	nop 0
748	;;
749	ld8 r21=[r2],PT(AR_RNAT)-PT(B0) // M0|1 load b0
750	ld8 r27=[r3],PT(PR)-PT(AR_RSC)	// M0|1 load ar.rsc
751	mov f6=f0			// F    clear f6
752	;;
753	ld8 r24=[r2],PT(AR_FPSR)-PT(AR_RNAT)	// M0|1 load ar.rnat (may be garbage)
754	ld8 r31=[r3],PT(R1)-PT(PR)		// M0|1 load predicates
755	mov f7=f0				// F    clear f7
756	;;
757	ld8 r20=[r2],PT(R12)-PT(AR_FPSR)	// M0|1 load ar.fpsr
758	ld8.fill r1=[r3],16			// M0|1 load r1
759(pUStk) mov r17=1				// A
760	;;
761(pUStk) st1 [r14]=r17				// M2|3
762	ld8.fill r13=[r3],16			// M0|1
763	mov f8=f0				// F    clear f8
764	;;
765	ld8.fill r12=[r2]			// M0|1 restore r12 (sp)
766	ld8.fill r15=[r3]			// M0|1 restore r15
767	mov b6=r18				// I0   restore b6
768
769	addl r17=THIS_CPU(ia64_phys_stacked_size_p8),r0 // A
770	mov f9=f0					// F    clear f9
771(pKStk) br.cond.dpnt.many skip_rbs_switch		// B
772
773	srlz.d				// M0   ensure interruption collection is off (for cover)
774	shr.u r18=r19,16		// I0|1 get byte size of existing "dirty" partition
775	cover				// B    add current frame into dirty partition & set cr.ifs
776	;;
777(pUStk) ld4 r17=[r17]			// M0|1 r17 = cpu_data->phys_stacked_size_p8
778	mov r19=ar.bsp			// M2   get new backing store pointer
779	mov f10=f0			// F    clear f10
780
781	nop.m 0
782	movl r14=__kernel_syscall_via_epc // X
783	;;
784	mov.m ar.csd=r0			// M2   clear ar.csd
785	mov.m ar.ccv=r0			// M2   clear ar.ccv
786	mov b7=r14			// I0   clear b7 (hint with __kernel_syscall_via_epc)
787
788	mov.m ar.ssd=r0			// M2   clear ar.ssd
789	mov f11=f0			// F    clear f11
790	br.cond.sptk.many rbs_switch	// B
791END(ia64_leave_syscall)
792
793#ifdef CONFIG_IA32_SUPPORT
794GLOBAL_ENTRY(ia64_ret_from_ia32_execve)
795	PT_REGS_UNWIND_INFO(0)
796	adds r2=PT(R8)+16,sp			// r2 = &pt_regs.r8
797	adds r3=PT(R10)+16,sp			// r3 = &pt_regs.r10
798	;;
799	.mem.offset 0,0
800	st8.spill [r2]=r8	// store return value in slot for r8 and set unat bit
801	.mem.offset 8,0
802	st8.spill [r3]=r0	// clear error indication in slot for r10 and set unat bit
803END(ia64_ret_from_ia32_execve)
804	// fall through
805#endif /* CONFIG_IA32_SUPPORT */
806GLOBAL_ENTRY(ia64_leave_kernel)
807	PT_REGS_UNWIND_INFO(0)
808	/*
809	 * work.need_resched etc. mustn't get changed by this CPU before it returns to
810	 * user- or fsys-mode, hence we disable interrupts early on.
811	 *
812	 * p6 controls whether current_thread_info()->flags needs to be check for
813	 * extra work.  We always check for extra work when returning to user-level.
814	 * With CONFIG_PREEMPT, we also check for extra work when the preempt_count
815	 * is 0.  After extra work processing has been completed, execution
816	 * resumes at .work_processed_syscall with p6 set to 1 if the extra-work-check
817	 * needs to be redone.
818	 */
819#ifdef CONFIG_PREEMPT
820	rsm psr.i				// disable interrupts
821	cmp.eq p0,pLvSys=r0,r0			// pLvSys=0: leave from kernel
822(pKStk)	adds r20=TI_PRE_COUNT+IA64_TASK_SIZE,r13
823	;;
824	.pred.rel.mutex pUStk,pKStk
825(pKStk)	ld4 r21=[r20]			// r21 <- preempt_count
826(pUStk)	mov r21=0			// r21 <- 0
827	;;
828	cmp.eq p6,p0=r21,r0		// p6 <- pUStk || (preempt_count == 0)
829#else
830(pUStk)	rsm psr.i
831	cmp.eq p0,pLvSys=r0,r0		// pLvSys=0: leave from kernel
832(pUStk)	cmp.eq.unc p6,p0=r0,r0		// p6 <- pUStk
833#endif
834.work_processed_kernel:
835	adds r17=TI_FLAGS+IA64_TASK_SIZE,r13
836	;;
837(p6)	ld4 r31=[r17]				// load current_thread_info()->flags
838	adds r21=PT(PR)+16,r12
839	;;
840
841	lfetch [r21],PT(CR_IPSR)-PT(PR)
842	adds r2=PT(B6)+16,r12
843	adds r3=PT(R16)+16,r12
844	;;
845	lfetch [r21]
846	ld8 r28=[r2],8		// load b6
847	adds r29=PT(R24)+16,r12
848
849	ld8.fill r16=[r3],PT(AR_CSD)-PT(R16)
850	adds r30=PT(AR_CCV)+16,r12
851(p6)	and r19=TIF_WORK_MASK,r31		// any work other than TIF_SYSCALL_TRACE?
852	;;
853	ld8.fill r24=[r29]
854	ld8 r15=[r30]		// load ar.ccv
855(p6)	cmp4.ne.unc p6,p0=r19, r0		// any special work pending?
856	;;
857	ld8 r29=[r2],16		// load b7
858	ld8 r30=[r3],16		// load ar.csd
859(p6)	br.cond.spnt .work_pending
860	;;
861	ld8 r31=[r2],16		// load ar.ssd
862	ld8.fill r8=[r3],16
863	;;
864	ld8.fill r9=[r2],16
865	ld8.fill r10=[r3],PT(R17)-PT(R10)
866	;;
867	ld8.fill r11=[r2],PT(R18)-PT(R11)
868	ld8.fill r17=[r3],16
869	;;
870	ld8.fill r18=[r2],16
871	ld8.fill r19=[r3],16
872	;;
873	ld8.fill r20=[r2],16
874	ld8.fill r21=[r3],16
875	mov ar.csd=r30
876	mov ar.ssd=r31
877	;;
878	rsm psr.i | psr.ic	// initiate turning off of interrupt and interruption collection
879	invala			// invalidate ALAT
880	;;
881	ld8.fill r22=[r2],24
882	ld8.fill r23=[r3],24
883	mov b6=r28
884	;;
885	ld8.fill r25=[r2],16
886	ld8.fill r26=[r3],16
887	mov b7=r29
888	;;
889	ld8.fill r27=[r2],16
890	ld8.fill r28=[r3],16
891	;;
892	ld8.fill r29=[r2],16
893	ld8.fill r30=[r3],24
894	;;
895	ld8.fill r31=[r2],PT(F9)-PT(R31)
896	adds r3=PT(F10)-PT(F6),r3
897	;;
898	ldf.fill f9=[r2],PT(F6)-PT(F9)
899	ldf.fill f10=[r3],PT(F8)-PT(F10)
900	;;
901	ldf.fill f6=[r2],PT(F7)-PT(F6)
902	;;
903	ldf.fill f7=[r2],PT(F11)-PT(F7)
904	ldf.fill f8=[r3],32
905	;;
906	srlz.d	// ensure that inter. collection is off (VHPT is don't care, since text is pinned)
907	mov ar.ccv=r15
908	;;
909	ldf.fill f11=[r2]
910	bsw.0			// switch back to bank 0 (no stop bit required beforehand...)
911	;;
912(pUStk)	mov r18=IA64_KR(CURRENT)// M2 (12 cycle read latency)
913	adds r16=PT(CR_IPSR)+16,r12
914	adds r17=PT(CR_IIP)+16,r12
915
916(pKStk)	mov r22=psr		// M2 read PSR now that interrupts are disabled
917	nop.i 0
918	nop.i 0
919	;;
920	ld8 r29=[r16],16	// load cr.ipsr
921	ld8 r28=[r17],16	// load cr.iip
922	;;
923	ld8 r30=[r16],16	// load cr.ifs
924	ld8 r25=[r17],16	// load ar.unat
925	;;
926	ld8 r26=[r16],16	// load ar.pfs
927	ld8 r27=[r17],16	// load ar.rsc
928	cmp.eq p9,p0=r0,r0	// set p9 to indicate that we should restore cr.ifs
929	;;
930	ld8 r24=[r16],16	// load ar.rnat (may be garbage)
931	ld8 r23=[r17],16	// load ar.bspstore (may be garbage)
932	;;
933	ld8 r31=[r16],16	// load predicates
934	ld8 r21=[r17],16	// load b0
935	;;
936	ld8 r19=[r16],16	// load ar.rsc value for "loadrs"
937	ld8.fill r1=[r17],16	// load r1
938	;;
939	ld8.fill r12=[r16],16
940	ld8.fill r13=[r17],16
941(pUStk)	adds r18=IA64_TASK_THREAD_ON_USTACK_OFFSET,r18
942	;;
943	ld8 r20=[r16],16	// ar.fpsr
944	ld8.fill r15=[r17],16
945	;;
946	ld8.fill r14=[r16],16
947	ld8.fill r2=[r17]
948(pUStk)	mov r17=1
949	;;
950	ld8.fill r3=[r16]
951(pUStk)	st1 [r18]=r17		// restore current->thread.on_ustack
952	shr.u r18=r19,16	// get byte size of existing "dirty" partition
953	;;
954	mov r16=ar.bsp		// get existing backing store pointer
955	addl r17=THIS_CPU(ia64_phys_stacked_size_p8),r0
956	;;
957	ld4 r17=[r17]		// r17 = cpu_data->phys_stacked_size_p8
958(pKStk)	br.cond.dpnt skip_rbs_switch
959
960	/*
961	 * Restore user backing store.
962	 *
963	 * NOTE: alloc, loadrs, and cover can't be predicated.
964	 */
965(pNonSys) br.cond.dpnt dont_preserve_current_frame
966	cover				// add current frame into dirty partition and set cr.ifs
967	;;
968	mov r19=ar.bsp			// get new backing store pointer
969rbs_switch:
970	sub r16=r16,r18			// krbs = old bsp - size of dirty partition
971	cmp.ne p9,p0=r0,r0		// clear p9 to skip restore of cr.ifs
972	;;
973	sub r19=r19,r16			// calculate total byte size of dirty partition
974	add r18=64,r18			// don't force in0-in7 into memory...
975	;;
976	shl r19=r19,16			// shift size of dirty partition into loadrs position
977	;;
978dont_preserve_current_frame:
979	/*
980	 * To prevent leaking bits between the kernel and user-space,
981	 * we must clear the stacked registers in the "invalid" partition here.
982	 * Not pretty, but at least it's fast (3.34 registers/cycle on Itanium,
983	 * 5 registers/cycle on McKinley).
984	 */
985#	define pRecurse	p6
986#	define pReturn	p7
987#ifdef CONFIG_ITANIUM
988#	define Nregs	10
989#else
990#	define Nregs	14
991#endif
992	alloc loc0=ar.pfs,2,Nregs-2,2,0
993	shr.u loc1=r18,9		// RNaTslots <= floor(dirtySize / (64*8))
994	sub r17=r17,r18			// r17 = (physStackedSize + 8) - dirtySize
995	;;
996	mov ar.rsc=r19			// load ar.rsc to be used for "loadrs"
997	shladd in0=loc1,3,r17
998	mov in1=0
999	;;
1000	TEXT_ALIGN(32)
1001rse_clear_invalid:
1002#ifdef CONFIG_ITANIUM
1003	// cycle 0
1004 { .mii
1005	alloc loc0=ar.pfs,2,Nregs-2,2,0
1006	cmp.lt pRecurse,p0=Nregs*8,in0	// if more than Nregs regs left to clear, (re)curse
1007	add out0=-Nregs*8,in0
1008}{ .mfb
1009	add out1=1,in1			// increment recursion count
1010	nop.f 0
1011	nop.b 0				// can't do br.call here because of alloc (WAW on CFM)
1012	;;
1013}{ .mfi	// cycle 1
1014	mov loc1=0
1015	nop.f 0
1016	mov loc2=0
1017}{ .mib
1018	mov loc3=0
1019	mov loc4=0
1020(pRecurse) br.call.sptk.many b0=rse_clear_invalid
1021
1022}{ .mfi	// cycle 2
1023	mov loc5=0
1024	nop.f 0
1025	cmp.ne pReturn,p0=r0,in1	// if recursion count != 0, we need to do a br.ret
1026}{ .mib
1027	mov loc6=0
1028	mov loc7=0
1029(pReturn) br.ret.sptk.many b0
1030}
1031#else /* !CONFIG_ITANIUM */
1032	alloc loc0=ar.pfs,2,Nregs-2,2,0
1033	cmp.lt pRecurse,p0=Nregs*8,in0	// if more than Nregs regs left to clear, (re)curse
1034	add out0=-Nregs*8,in0
1035	add out1=1,in1			// increment recursion count
1036	mov loc1=0
1037	mov loc2=0
1038	;;
1039	mov loc3=0
1040	mov loc4=0
1041	mov loc5=0
1042	mov loc6=0
1043	mov loc7=0
1044(pRecurse) br.call.dptk.few b0=rse_clear_invalid
1045	;;
1046	mov loc8=0
1047	mov loc9=0
1048	cmp.ne pReturn,p0=r0,in1	// if recursion count != 0, we need to do a br.ret
1049	mov loc10=0
1050	mov loc11=0
1051(pReturn) br.ret.dptk.many b0
1052#endif /* !CONFIG_ITANIUM */
1053#	undef pRecurse
1054#	undef pReturn
1055	;;
1056	alloc r17=ar.pfs,0,0,0,0	// drop current register frame
1057	;;
1058	loadrs
1059	;;
1060skip_rbs_switch:
1061	mov ar.unat=r25		// M2
1062(pKStk)	extr.u r22=r22,21,1	// I0 extract current value of psr.pp from r22
1063(pLvSys)mov r19=r0		// A  clear r19 for leave_syscall, no-op otherwise
1064	;;
1065(pUStk)	mov ar.bspstore=r23	// M2
1066(pKStk)	dep r29=r22,r29,21,1	// I0 update ipsr.pp with psr.pp
1067(pLvSys)mov r16=r0		// A  clear r16 for leave_syscall, no-op otherwise
1068	;;
1069	mov cr.ipsr=r29		// M2
1070	mov ar.pfs=r26		// I0
1071(pLvSys)mov r17=r0		// A  clear r17 for leave_syscall, no-op otherwise
1072
1073(p9)	mov cr.ifs=r30		// M2
1074	mov b0=r21		// I0
1075(pLvSys)mov r18=r0		// A  clear r18 for leave_syscall, no-op otherwise
1076
1077	mov ar.fpsr=r20		// M2
1078	mov cr.iip=r28		// M2
1079	nop 0
1080	;;
1081(pUStk)	mov ar.rnat=r24		// M2 must happen with RSE in lazy mode
1082	nop 0
1083(pLvSys)mov r2=r0
1084
1085	mov ar.rsc=r27		// M2
1086	mov pr=r31,-1		// I0
1087	rfi			// B
1088
1089	/*
1090	 * On entry:
1091	 *	r20 = &current->thread_info->pre_count (if CONFIG_PREEMPT)
1092	 *	r31 = current->thread_info->flags
1093	 * On exit:
1094	 *	p6 = TRUE if work-pending-check needs to be redone
1095	 */
1096.work_pending_syscall:
1097	add r2=-8,r2
1098	add r3=-8,r3
1099	;;
1100	st8 [r2]=r8
1101	st8 [r3]=r10
1102.work_pending:
1103	tbit.nz p6,p0=r31,TIF_SIGDELAYED		// signal delayed from  MCA/INIT/NMI/PMI context?
1104(p6)	br.cond.sptk.few .sigdelayed
1105	;;
1106	tbit.z p6,p0=r31,TIF_NEED_RESCHED		// current_thread_info()->need_resched==0?
1107(p6)	br.cond.sptk.few .notify
1108#ifdef CONFIG_PREEMPT
1109(pKStk) dep r21=-1,r0,PREEMPT_ACTIVE_BIT,1
1110	;;
1111(pKStk) st4 [r20]=r21
1112	ssm psr.i		// enable interrupts
1113#endif
1114	br.call.spnt.many rp=schedule
1115.ret9:	cmp.eq p6,p0=r0,r0				// p6 <- 1
1116	rsm psr.i		// disable interrupts
1117	;;
1118#ifdef CONFIG_PREEMPT
1119(pKStk)	adds r20=TI_PRE_COUNT+IA64_TASK_SIZE,r13
1120	;;
1121(pKStk)	st4 [r20]=r0		// preempt_count() <- 0
1122#endif
1123(pLvSys)br.cond.sptk.few  .work_pending_syscall_end
1124	br.cond.sptk.many .work_processed_kernel	// re-check
1125
1126.notify:
1127(pUStk)	br.call.spnt.many rp=notify_resume_user
1128.ret10:	cmp.ne p6,p0=r0,r0				// p6 <- 0
1129(pLvSys)br.cond.sptk.few  .work_pending_syscall_end
1130	br.cond.sptk.many .work_processed_kernel	// don't re-check
1131
1132// There is a delayed signal that was detected in MCA/INIT/NMI/PMI context where
1133// it could not be delivered.  Deliver it now.  The signal might be for us and
1134// may set TIF_SIGPENDING, so redrive ia64_leave_* after processing the delayed
1135// signal.
1136
1137.sigdelayed:
1138	br.call.sptk.many rp=do_sigdelayed
1139	cmp.eq p6,p0=r0,r0				// p6 <- 1, always re-check
1140(pLvSys)br.cond.sptk.few  .work_pending_syscall_end
1141	br.cond.sptk.many .work_processed_kernel	// re-check
1142
1143.work_pending_syscall_end:
1144	adds r2=PT(R8)+16,r12
1145	adds r3=PT(R10)+16,r12
1146	;;
1147	ld8 r8=[r2]
1148	ld8 r10=[r3]
1149	br.cond.sptk.many .work_processed_syscall	// re-check
1150
1151END(ia64_leave_kernel)
1152
1153ENTRY(handle_syscall_error)
1154	/*
1155	 * Some system calls (e.g., ptrace, mmap) can return arbitrary values which could
1156	 * lead us to mistake a negative return value as a failed syscall.  Those syscall
1157	 * must deposit a non-zero value in pt_regs.r8 to indicate an error.  If
1158	 * pt_regs.r8 is zero, we assume that the call completed successfully.
1159	 */
1160	PT_REGS_UNWIND_INFO(0)
1161	ld8 r3=[r2]		// load pt_regs.r8
1162	;;
1163	cmp.eq p6,p7=r3,r0	// is pt_regs.r8==0?
1164	;;
1165(p7)	mov r10=-1
1166(p7)	sub r8=0,r8		// negate return value to get errno
1167	br.cond.sptk ia64_leave_syscall
1168END(handle_syscall_error)
1169
1170	/*
1171	 * Invoke schedule_tail(task) while preserving in0-in7, which may be needed
1172	 * in case a system call gets restarted.
1173	 */
1174GLOBAL_ENTRY(ia64_invoke_schedule_tail)
1175	.prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(8)
1176	alloc loc1=ar.pfs,8,2,1,0
1177	mov loc0=rp
1178	mov out0=r8				// Address of previous task
1179	;;
1180	br.call.sptk.many rp=schedule_tail
1181.ret11:	mov ar.pfs=loc1
1182	mov rp=loc0
1183	br.ret.sptk.many rp
1184END(ia64_invoke_schedule_tail)
1185
1186	/*
1187	 * Setup stack and call do_notify_resume_user().  Note that pSys and pNonSys need to
1188	 * be set up by the caller.  We declare 8 input registers so the system call
1189	 * args get preserved, in case we need to restart a system call.
1190	 */
1191ENTRY(notify_resume_user)
1192	.prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(8)
1193	alloc loc1=ar.pfs,8,2,3,0 // preserve all eight input regs in case of syscall restart!
1194	mov r9=ar.unat
1195	mov loc0=rp				// save return address
1196	mov out0=0				// there is no "oldset"
1197	adds out1=8,sp				// out1=&sigscratch->ar_pfs
1198(pSys)	mov out2=1				// out2==1 => we're in a syscall
1199	;;
1200(pNonSys) mov out2=0				// out2==0 => not a syscall
1201	.fframe 16
1202	.spillsp ar.unat, 16
1203	st8 [sp]=r9,-16				// allocate space for ar.unat and save it
1204	st8 [out1]=loc1,-8			// save ar.pfs, out1=&sigscratch
1205	.body
1206	br.call.sptk.many rp=do_notify_resume_user
1207.ret15:	.restore sp
1208	adds sp=16,sp				// pop scratch stack space
1209	;;
1210	ld8 r9=[sp]				// load new unat from sigscratch->scratch_unat
1211	mov rp=loc0
1212	;;
1213	mov ar.unat=r9
1214	mov ar.pfs=loc1
1215	br.ret.sptk.many rp
1216END(notify_resume_user)
1217
1218GLOBAL_ENTRY(sys_rt_sigsuspend)
1219	.prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(8)
1220	alloc loc1=ar.pfs,8,2,3,0 // preserve all eight input regs in case of syscall restart!
1221	mov r9=ar.unat
1222	mov loc0=rp				// save return address
1223	mov out0=in0				// mask
1224	mov out1=in1				// sigsetsize
1225	adds out2=8,sp				// out2=&sigscratch->ar_pfs
1226	;;
1227	.fframe 16
1228	.spillsp ar.unat, 16
1229	st8 [sp]=r9,-16				// allocate space for ar.unat and save it
1230	st8 [out2]=loc1,-8			// save ar.pfs, out2=&sigscratch
1231	.body
1232	br.call.sptk.many rp=ia64_rt_sigsuspend
1233.ret17:	.restore sp
1234	adds sp=16,sp				// pop scratch stack space
1235	;;
1236	ld8 r9=[sp]				// load new unat from sw->caller_unat
1237	mov rp=loc0
1238	;;
1239	mov ar.unat=r9
1240	mov ar.pfs=loc1
1241	br.ret.sptk.many rp
1242END(sys_rt_sigsuspend)
1243
1244ENTRY(sys_rt_sigreturn)
1245	PT_REGS_UNWIND_INFO(0)
1246	/*
1247	 * Allocate 8 input registers since ptrace() may clobber them
1248	 */
1249	alloc r2=ar.pfs,8,0,1,0
1250	.prologue
1251	PT_REGS_SAVES(16)
1252	adds sp=-16,sp
1253	.body
1254	cmp.eq pNonSys,pSys=r0,r0		// sigreturn isn't a normal syscall...
1255	;;
1256	/*
1257	 * leave_kernel() restores f6-f11 from pt_regs, but since the streamlined
1258	 * syscall-entry path does not save them we save them here instead.  Note: we
1259	 * don't need to save any other registers that are not saved by the stream-lined
1260	 * syscall path, because restore_sigcontext() restores them.
1261	 */
1262	adds r16=PT(F6)+32,sp
1263	adds r17=PT(F7)+32,sp
1264	;;
1265 	stf.spill [r16]=f6,32
1266 	stf.spill [r17]=f7,32
1267	;;
1268 	stf.spill [r16]=f8,32
1269 	stf.spill [r17]=f9,32
1270	;;
1271 	stf.spill [r16]=f10
1272 	stf.spill [r17]=f11
1273	adds out0=16,sp				// out0 = &sigscratch
1274	br.call.sptk.many rp=ia64_rt_sigreturn
1275.ret19:	.restore sp,0
1276	adds sp=16,sp
1277	;;
1278	ld8 r9=[sp]				// load new ar.unat
1279	mov.sptk b7=r8,ia64_leave_kernel
1280	;;
1281	mov ar.unat=r9
1282	br.many b7
1283END(sys_rt_sigreturn)
1284
1285GLOBAL_ENTRY(ia64_prepare_handle_unaligned)
1286	.prologue
1287	/*
1288	 * r16 = fake ar.pfs, we simply need to make sure privilege is still 0
1289	 */
1290	mov r16=r0
1291	DO_SAVE_SWITCH_STACK
1292	br.call.sptk.many rp=ia64_handle_unaligned	// stack frame setup in ivt
1293.ret21:	.body
1294	DO_LOAD_SWITCH_STACK
1295	br.cond.sptk.many rp				// goes to ia64_leave_kernel
1296END(ia64_prepare_handle_unaligned)
1297
1298	//
1299	// unw_init_running(void (*callback)(info, arg), void *arg)
1300	//
1301#	define EXTRA_FRAME_SIZE	((UNW_FRAME_INFO_SIZE+15)&~15)
1302
1303GLOBAL_ENTRY(unw_init_running)
1304	.prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(2)
1305	alloc loc1=ar.pfs,2,3,3,0
1306	;;
1307	ld8 loc2=[in0],8
1308	mov loc0=rp
1309	mov r16=loc1
1310	DO_SAVE_SWITCH_STACK
1311	.body
1312
1313	.prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(2)
1314	.fframe IA64_SWITCH_STACK_SIZE+EXTRA_FRAME_SIZE
1315	SWITCH_STACK_SAVES(EXTRA_FRAME_SIZE)
1316	adds sp=-EXTRA_FRAME_SIZE,sp
1317	.body
1318	;;
1319	adds out0=16,sp				// &info
1320	mov out1=r13				// current
1321	adds out2=16+EXTRA_FRAME_SIZE,sp	// &switch_stack
1322	br.call.sptk.many rp=unw_init_frame_info
13231:	adds out0=16,sp				// &info
1324	mov b6=loc2
1325	mov loc2=gp				// save gp across indirect function call
1326	;;
1327	ld8 gp=[in0]
1328	mov out1=in1				// arg
1329	br.call.sptk.many rp=b6			// invoke the callback function
13301:	mov gp=loc2				// restore gp
1331
1332	// For now, we don't allow changing registers from within
1333	// unw_init_running; if we ever want to allow that, we'd
1334	// have to do a load_switch_stack here:
1335	.restore sp
1336	adds sp=IA64_SWITCH_STACK_SIZE+EXTRA_FRAME_SIZE,sp
1337
1338	mov ar.pfs=loc1
1339	mov rp=loc0
1340	br.ret.sptk.many rp
1341END(unw_init_running)
1342
1343	.rodata
1344	.align 8
1345	.globl sys_call_table
1346sys_call_table:
1347	data8 sys_ni_syscall		//  This must be sys_ni_syscall!  See ivt.S.
1348	data8 sys_exit				// 1025
1349	data8 sys_read
1350	data8 sys_write
1351	data8 sys_open
1352	data8 sys_close
1353	data8 sys_creat				// 1030
1354	data8 sys_link
1355	data8 sys_unlink
1356	data8 ia64_execve
1357	data8 sys_chdir
1358	data8 sys_fchdir			// 1035
1359	data8 sys_utimes
1360	data8 sys_mknod
1361	data8 sys_chmod
1362	data8 sys_chown
1363	data8 sys_lseek				// 1040
1364	data8 sys_getpid
1365	data8 sys_getppid
1366	data8 sys_mount
1367	data8 sys_umount
1368	data8 sys_setuid			// 1045
1369	data8 sys_getuid
1370	data8 sys_geteuid
1371	data8 sys_ptrace
1372	data8 sys_access
1373	data8 sys_sync				// 1050
1374	data8 sys_fsync
1375	data8 sys_fdatasync
1376	data8 sys_kill
1377	data8 sys_rename
1378	data8 sys_mkdir				// 1055
1379	data8 sys_rmdir
1380	data8 sys_dup
1381	data8 sys_pipe
1382	data8 sys_times
1383	data8 ia64_brk				// 1060
1384	data8 sys_setgid
1385	data8 sys_getgid
1386	data8 sys_getegid
1387	data8 sys_acct
1388	data8 sys_ioctl				// 1065
1389	data8 sys_fcntl
1390	data8 sys_umask
1391	data8 sys_chroot
1392	data8 sys_ustat
1393	data8 sys_dup2				// 1070
1394	data8 sys_setreuid
1395	data8 sys_setregid
1396	data8 sys_getresuid
1397	data8 sys_setresuid
1398	data8 sys_getresgid			// 1075
1399	data8 sys_setresgid
1400	data8 sys_getgroups
1401	data8 sys_setgroups
1402	data8 sys_getpgid
1403	data8 sys_setpgid			// 1080
1404	data8 sys_setsid
1405	data8 sys_getsid
1406	data8 sys_sethostname
1407	data8 sys_setrlimit
1408	data8 sys_getrlimit			// 1085
1409	data8 sys_getrusage
1410	data8 sys_gettimeofday
1411	data8 sys_settimeofday
1412	data8 sys_select
1413	data8 sys_poll				// 1090
1414	data8 sys_symlink
1415	data8 sys_readlink
1416	data8 sys_uselib
1417	data8 sys_swapon
1418	data8 sys_swapoff			// 1095
1419	data8 sys_reboot
1420	data8 sys_truncate
1421	data8 sys_ftruncate
1422	data8 sys_fchmod
1423	data8 sys_fchown			// 1100
1424	data8 ia64_getpriority
1425	data8 sys_setpriority
1426	data8 sys_statfs
1427	data8 sys_fstatfs
1428	data8 sys_gettid			// 1105
1429	data8 sys_semget
1430	data8 sys_semop
1431	data8 sys_semctl
1432	data8 sys_msgget
1433	data8 sys_msgsnd			// 1110
1434	data8 sys_msgrcv
1435	data8 sys_msgctl
1436	data8 sys_shmget
1437	data8 sys_shmat
1438	data8 sys_shmdt				// 1115
1439	data8 sys_shmctl
1440	data8 sys_syslog
1441	data8 sys_setitimer
1442	data8 sys_getitimer
1443	data8 sys_ni_syscall			// 1120		/* was: ia64_oldstat */
1444	data8 sys_ni_syscall					/* was: ia64_oldlstat */
1445	data8 sys_ni_syscall					/* was: ia64_oldfstat */
1446	data8 sys_vhangup
1447	data8 sys_lchown
1448	data8 sys_remap_file_pages		// 1125
1449	data8 sys_wait4
1450	data8 sys_sysinfo
1451	data8 sys_clone
1452	data8 sys_setdomainname
1453	data8 sys_newuname			// 1130
1454	data8 sys_adjtimex
1455	data8 sys_ni_syscall					/* was: ia64_create_module */
1456	data8 sys_init_module
1457	data8 sys_delete_module
1458	data8 sys_ni_syscall			// 1135		/* was: sys_get_kernel_syms */
1459	data8 sys_ni_syscall					/* was: sys_query_module */
1460	data8 sys_quotactl
1461	data8 sys_bdflush
1462	data8 sys_sysfs
1463	data8 sys_personality			// 1140
1464	data8 sys_ni_syscall		// sys_afs_syscall
1465	data8 sys_setfsuid
1466	data8 sys_setfsgid
1467	data8 sys_getdents
1468	data8 sys_flock				// 1145
1469	data8 sys_readv
1470	data8 sys_writev
1471	data8 sys_pread64
1472	data8 sys_pwrite64
1473	data8 sys_sysctl			// 1150
1474	data8 sys_mmap
1475	data8 sys_munmap
1476	data8 sys_mlock
1477	data8 sys_mlockall
1478	data8 sys_mprotect			// 1155
1479	data8 ia64_mremap
1480	data8 sys_msync
1481	data8 sys_munlock
1482	data8 sys_munlockall
1483	data8 sys_sched_getparam		// 1160
1484	data8 sys_sched_setparam
1485	data8 sys_sched_getscheduler
1486	data8 sys_sched_setscheduler
1487	data8 sys_sched_yield
1488	data8 sys_sched_get_priority_max	// 1165
1489	data8 sys_sched_get_priority_min
1490	data8 sys_sched_rr_get_interval
1491	data8 sys_nanosleep
1492	data8 sys_nfsservctl
1493	data8 sys_prctl				// 1170
1494	data8 sys_getpagesize
1495	data8 sys_mmap2
1496	data8 sys_pciconfig_read
1497	data8 sys_pciconfig_write
1498	data8 sys_perfmonctl			// 1175
1499	data8 sys_sigaltstack
1500	data8 sys_rt_sigaction
1501	data8 sys_rt_sigpending
1502	data8 sys_rt_sigprocmask
1503	data8 sys_rt_sigqueueinfo		// 1180
1504	data8 sys_rt_sigreturn
1505	data8 sys_rt_sigsuspend
1506	data8 sys_rt_sigtimedwait
1507	data8 sys_getcwd
1508	data8 sys_capget			// 1185
1509	data8 sys_capset
1510	data8 sys_sendfile64
1511	data8 sys_ni_syscall		// sys_getpmsg (STREAMS)
1512	data8 sys_ni_syscall		// sys_putpmsg (STREAMS)
1513	data8 sys_socket			// 1190
1514	data8 sys_bind
1515	data8 sys_connect
1516	data8 sys_listen
1517	data8 sys_accept
1518	data8 sys_getsockname			// 1195
1519	data8 sys_getpeername
1520	data8 sys_socketpair
1521	data8 sys_send
1522	data8 sys_sendto
1523	data8 sys_recv				// 1200
1524	data8 sys_recvfrom
1525	data8 sys_shutdown
1526	data8 sys_setsockopt
1527	data8 sys_getsockopt
1528	data8 sys_sendmsg			// 1205
1529	data8 sys_recvmsg
1530	data8 sys_pivot_root
1531	data8 sys_mincore
1532	data8 sys_madvise
1533	data8 sys_newstat			// 1210
1534	data8 sys_newlstat
1535	data8 sys_newfstat
1536	data8 sys_clone2
1537	data8 sys_getdents64
1538	data8 sys_getunwind			// 1215
1539	data8 sys_readahead
1540	data8 sys_setxattr
1541	data8 sys_lsetxattr
1542	data8 sys_fsetxattr
1543	data8 sys_getxattr			// 1220
1544	data8 sys_lgetxattr
1545	data8 sys_fgetxattr
1546	data8 sys_listxattr
1547	data8 sys_llistxattr
1548	data8 sys_flistxattr			// 1225
1549	data8 sys_removexattr
1550	data8 sys_lremovexattr
1551	data8 sys_fremovexattr
1552	data8 sys_tkill
1553	data8 sys_futex				// 1230
1554	data8 sys_sched_setaffinity
1555	data8 sys_sched_getaffinity
1556	data8 sys_set_tid_address
1557	data8 sys_fadvise64_64
1558	data8 sys_tgkill 			// 1235
1559	data8 sys_exit_group
1560	data8 sys_lookup_dcookie
1561	data8 sys_io_setup
1562	data8 sys_io_destroy
1563	data8 sys_io_getevents			// 1240
1564	data8 sys_io_submit
1565	data8 sys_io_cancel
1566	data8 sys_epoll_create
1567	data8 sys_epoll_ctl
1568	data8 sys_epoll_wait			// 1245
1569	data8 sys_restart_syscall
1570	data8 sys_semtimedop
1571	data8 sys_timer_create
1572	data8 sys_timer_settime
1573	data8 sys_timer_gettime			// 1250
1574	data8 sys_timer_getoverrun
1575	data8 sys_timer_delete
1576	data8 sys_clock_settime
1577	data8 sys_clock_gettime
1578	data8 sys_clock_getres			// 1255
1579	data8 sys_clock_nanosleep
1580	data8 sys_fstatfs64
1581	data8 sys_statfs64
1582	data8 sys_mbind
1583	data8 sys_get_mempolicy			// 1260
1584	data8 sys_set_mempolicy
1585	data8 sys_mq_open
1586	data8 sys_mq_unlink
1587	data8 sys_mq_timedsend
1588	data8 sys_mq_timedreceive		// 1265
1589	data8 sys_mq_notify
1590	data8 sys_mq_getsetattr
1591	data8 sys_ni_syscall			// reserved for kexec_load
1592	data8 sys_ni_syscall			// reserved for vserver
1593	data8 sys_waitid			// 1270
1594	data8 sys_add_key
1595	data8 sys_request_key
1596	data8 sys_keyctl
1597	data8 sys_ioprio_set
1598	data8 sys_ioprio_get			// 1275
1599	data8 sys_ni_syscall
1600	data8 sys_inotify_init
1601	data8 sys_inotify_add_watch
1602	data8 sys_inotify_rm_watch
1603	data8 sys_migrate_pages			// 1280
1604
1605	.org sys_call_table + 8*NR_syscalls	// guard against failures to increase NR_syscalls
1606