Linux Audio

Check our new training course

Loading...
v6.2
  1/* SPDX-License-Identifier: GPL-2.0 */
  2/*
  3 * This file contains the light-weight system call handlers (fsyscall-handlers).
  4 *
  5 * Copyright (C) 2003 Hewlett-Packard Co
  6 * 	David Mosberger-Tang <davidm@hpl.hp.com>
  7 *
  8 * 25-Sep-03 davidm	Implement fsys_rt_sigprocmask().
  9 * 18-Feb-03 louisk	Implement fsys_gettimeofday().
 10 * 28-Feb-03 davidm	Fixed several bugs in fsys_gettimeofday().  Tuned it some more,
 11 *			probably broke it along the way... ;-)
 12 * 13-Jul-04 clameter   Implement fsys_clock_gettime and revise fsys_gettimeofday to make
 13 *                      it capable of using memory based clocks without falling back to C code.
 14 * 08-Feb-07 Fenghua Yu Implement fsys_getcpu.
 15 *
 16 */
 17
 18#include <asm/asmmacro.h>
 19#include <asm/errno.h>
 20#include <asm/asm-offsets.h>
 21#include <asm/percpu.h>
 22#include <asm/thread_info.h>
 23#include <asm/sal.h>
 24#include <asm/signal.h>
 25#include <asm/unistd.h>
 26
 27#include "entry.h"
 28#include <asm/native/inst.h>
 29
 30/*
 31 * See Documentation/ia64/fsys.rst for details on fsyscalls.
 32 *
 33 * On entry to an fsyscall handler:
 34 *   r10	= 0 (i.e., defaults to "successful syscall return")
 35 *   r11	= saved ar.pfs (a user-level value)
 36 *   r15	= system call number
 37 *   r16	= "current" task pointer (in normal kernel-mode, this is in r13)
 38 *   r32-r39	= system call arguments
 39 *   b6		= return address (a user-level value)
 40 *   ar.pfs	= previous frame-state (a user-level value)
 41 *   PSR.be	= cleared to zero (i.e., little-endian byte order is in effect)
 42 *   all other registers may contain values passed in from user-mode
 43 *
 44 * On return from an fsyscall handler:
 45 *   r11	= saved ar.pfs (as passed into the fsyscall handler)
 46 *   r15	= system call number (as passed into the fsyscall handler)
 47 *   r32-r39	= system call arguments (as passed into the fsyscall handler)
 48 *   b6		= return address (as passed into the fsyscall handler)
 49 *   ar.pfs	= previous frame-state (as passed into the fsyscall handler)
 50 */
 51
 52ENTRY(fsys_ni_syscall)
 53	.prologue
 54	.altrp b6
 55	.body
 56	mov r8=ENOSYS
 57	mov r10=-1
 58	FSYS_RETURN
 59END(fsys_ni_syscall)
 60
 61ENTRY(fsys_getpid)
 62	.prologue
 63	.altrp b6
 64	.body
 65	add r17=IA64_TASK_SIGNAL_OFFSET,r16
 66	;;
 67	ld8 r17=[r17]				// r17 = current->signal
 68	add r9=TI_FLAGS+IA64_TASK_SIZE,r16
 69	;;
 70	ld4 r9=[r9]
 71	add r17=IA64_SIGNAL_PIDS_TGID_OFFSET,r17
 72	;;
 73	and r9=TIF_ALLWORK_MASK,r9
 74	ld8 r17=[r17]				// r17 = current->signal->pids[PIDTYPE_TGID]
 75	;;
 76	add r8=IA64_PID_LEVEL_OFFSET,r17
 77	;;
 78	ld4 r8=[r8]				// r8 = pid->level
 79	add r17=IA64_PID_UPID_OFFSET,r17	// r17 = &pid->numbers[0]
 80	;;
 81	shl r8=r8,IA64_UPID_SHIFT
 82	;;
 83	add r17=r17,r8				// r17 = &pid->numbers[pid->level]
 84	;;
 85	ld4 r8=[r17]				// r8 = pid->numbers[pid->level].nr
 86	;;
 87	mov r17=0
 88	;;
 89	cmp.ne p8,p0=0,r9
 90(p8)	br.spnt.many fsys_fallback_syscall
 91	FSYS_RETURN
 92END(fsys_getpid)
 93
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 94ENTRY(fsys_set_tid_address)
 95	.prologue
 96	.altrp b6
 97	.body
 98	add r9=TI_FLAGS+IA64_TASK_SIZE,r16
 99	add r17=IA64_TASK_THREAD_PID_OFFSET,r16
100	;;
101	ld4 r9=[r9]
102	tnat.z p6,p7=r32		// check argument register for being NaT
103	ld8 r17=[r17]				// r17 = current->thread_pid
104	;;
105	and r9=TIF_ALLWORK_MASK,r9
106	add r8=IA64_PID_LEVEL_OFFSET,r17
107	add r18=IA64_TASK_CLEAR_CHILD_TID_OFFSET,r16
108	;;
109	ld4 r8=[r8]				// r8 = pid->level
110	add r17=IA64_PID_UPID_OFFSET,r17	// r17 = &pid->numbers[0]
111	;;
112	shl r8=r8,IA64_UPID_SHIFT
113	;;
114	add r17=r17,r8				// r17 = &pid->numbers[pid->level]
115	;;
116	ld4 r8=[r17]				// r8 = pid->numbers[pid->level].nr
117	;;
118	cmp.ne p8,p0=0,r9
119	mov r17=-1
120	;;
121(p6)	st8 [r18]=r32
122(p7)	st8 [r18]=r17
123(p8)	br.spnt.many fsys_fallback_syscall
124	;;
125	mov r17=0			// i must not leak kernel bits...
126	mov r18=0			// i must not leak kernel bits...
127	FSYS_RETURN
128END(fsys_set_tid_address)
129
130#if IA64_GTOD_SEQ_OFFSET !=0
131#error fsys_gettimeofday incompatible with changes to struct fsyscall_gtod_data_t
132#endif
133#if IA64_ITC_JITTER_OFFSET !=0
134#error fsys_gettimeofday incompatible with changes to struct itc_jitter_data_t
135#endif
136#define CLOCK_REALTIME 0
137#define CLOCK_MONOTONIC 1
138#define CLOCK_DIVIDE_BY_1000 0x4000
139#define CLOCK_ADD_MONOTONIC 0x8000
140
141ENTRY(fsys_gettimeofday)
142	.prologue
143	.altrp b6
144	.body
145	mov r31 = r32
146	tnat.nz p6,p0 = r33		// guard against NaT argument
147(p6)    br.cond.spnt.few .fail_einval
148	mov r30 = CLOCK_DIVIDE_BY_1000
149	;;
150.gettime:
151	// Register map
152	// Incoming r31 = pointer to address where to place result
153	//          r30 = flags determining how time is processed
154	// r2,r3 = temp r4-r7 preserved
155	// r8 = result nanoseconds
156	// r9 = result seconds
157	// r10 = temporary storage for clock difference
158	// r11 = preserved: saved ar.pfs
159	// r12 = preserved: memory stack
160	// r13 = preserved: thread pointer
161	// r14 = address of mask / mask value
162	// r15 = preserved: system call number
163	// r16 = preserved: current task pointer
164	// r17 = (not used)
165	// r18 = (not used)
166	// r19 = address of itc_lastcycle
167	// r20 = struct fsyscall_gtod_data (= address of gtod_lock.sequence)
168	// r21 = address of mmio_ptr
169	// r22 = address of wall_time or monotonic_time
170	// r23 = address of shift / value
171	// r24 = address mult factor / cycle_last value
172	// r25 = itc_lastcycle value
173	// r26 = address clocksource cycle_last
174	// r27 = (not used)
175	// r28 = sequence number at the beginning of critical section
176	// r29 = address of itc_jitter
177	// r30 = time processing flags / memory address
178	// r31 = pointer to result
179	// Predicates
180	// p6,p7 short term use
181	// p8 = timesource ar.itc
182	// p9 = timesource mmio64
183	// p10 = timesource mmio32 - not used
184	// p11 = timesource not to be handled by asm code
185	// p12 = memory time source ( = p9 | p10) - not used
186	// p13 = do cmpxchg with itc_lastcycle
187	// p14 = Divide by 1000
188	// p15 = Add monotonic
189	//
190	// Note that instructions are optimized for McKinley. McKinley can
191	// process two bundles simultaneously and therefore we continuously
192	// try to feed the CPU two bundles and then a stop.
193
194	add r2 = TI_FLAGS+IA64_TASK_SIZE,r16
195	tnat.nz p6,p0 = r31		// guard against Nat argument
196(p6)	br.cond.spnt.few .fail_einval
197	movl r20 = fsyscall_gtod_data // load fsyscall gettimeofday data address
198	;;
199	ld4 r2 = [r2]			// process work pending flags
200	movl r29 = itc_jitter_data	// itc_jitter
201	add r22 = IA64_GTOD_WALL_TIME_OFFSET,r20	// wall_time
202	add r21 = IA64_CLKSRC_MMIO_OFFSET,r20
203	mov pr = r30,0xc000	// Set predicates according to function
204	;;
205	and r2 = TIF_ALLWORK_MASK,r2
206	add r19 = IA64_ITC_LASTCYCLE_OFFSET,r29
207(p15)	add r22 = IA64_GTOD_MONO_TIME_OFFSET,r20	// monotonic_time
208	;;
209	add r26 = IA64_CLKSRC_CYCLE_LAST_OFFSET,r20	// clksrc_cycle_last
210	cmp.ne p6, p0 = 0, r2	// Fallback if work is scheduled
211(p6)	br.cond.spnt.many fsys_fallback_syscall
212	;;
213	// Begin critical section
214.time_redo:
215	ld4.acq r28 = [r20]	// gtod_lock.sequence, Must take first
216	;;
217	and r28 = ~1,r28	// And make sequence even to force retry if odd
218	;;
219	ld8 r30 = [r21]		// clocksource->mmio_ptr
220	add r24 = IA64_CLKSRC_MULT_OFFSET,r20
221	ld4 r2 = [r29]		// itc_jitter value
222	add r23 = IA64_CLKSRC_SHIFT_OFFSET,r20
223	add r14 = IA64_CLKSRC_MASK_OFFSET,r20
224	;;
225	ld4 r3 = [r24]		// clocksource mult value
226	ld8 r14 = [r14]         // clocksource mask value
227	cmp.eq p8,p9 = 0,r30	// use cpu timer if no mmio_ptr
228	;;
229	setf.sig f7 = r3	// Setup for mult scaling of counter
230(p8)	cmp.ne p13,p0 = r2,r0	// need itc_jitter compensation, set p13
231	ld4 r23 = [r23]		// clocksource shift value
232	ld8 r24 = [r26]		// get clksrc_cycle_last value
233(p9)	cmp.eq p13,p0 = 0,r30	// if mmio_ptr, clear p13 jitter control
234	;;
235	.pred.rel.mutex p8,p9
236	MOV_FROM_ITC(p8, p6, r2, r10)	// CPU_TIMER. 36 clocks latency!!!
237(p9)	ld8 r2 = [r30]		// MMIO_TIMER. Could also have latency issues..
238(p13)	ld8 r25 = [r19]		// get itc_lastcycle value
239	ld8 r9 = [r22],IA64_TIME_SN_SPEC_SNSEC_OFFSET	// sec
240	;;
241	ld8 r8 = [r22],-IA64_TIME_SN_SPEC_SNSEC_OFFSET	// snsec
242(p13)	sub r3 = r25,r2		// Diff needed before comparison (thanks davidm)
243	;;
244(p13)	cmp.gt.unc p6,p7 = r3,r0 // check if it is less than last. p6,p7 cleared
245	sub r10 = r2,r24	// current_cycle - last_cycle
246	;;
247(p6)	sub r10 = r25,r24	// time we got was less than last_cycle
248(p7)	mov ar.ccv = r25	// more than last_cycle. Prep for cmpxchg
249	;;
250(p7)	cmpxchg8.rel r3 = [r19],r2,ar.ccv
251	;;
252(p7)	cmp.ne p7,p0 = r25,r3	// if cmpxchg not successful
253	;;
254(p7)	sub r10 = r3,r24	// then use new last_cycle instead
255	;;
256	and r10 = r10,r14	// Apply mask
257	;;
258	setf.sig f8 = r10
259	nop.i 123
260	;;
261	// fault check takes 5 cycles and we have spare time
262EX(.fail_efault, probe.w.fault r31, 3)
263	xmpy.l f8 = f8,f7	// nsec_per_cyc*(counter-last_counter)
264	;;
265	getf.sig r2 = f8
266	mf
267	;;
268	ld4 r10 = [r20]		// gtod_lock.sequence
269	add r8 = r8,r2		// Add xtime.nsecs
270	;;
271	shr.u r8 = r8,r23	// shift by factor
272	cmp4.ne p7,p0 = r28,r10
273(p7)	br.cond.dpnt.few .time_redo	// sequence number changed, redo
274	// End critical section.
275	// Now r8=tv->tv_nsec and r9=tv->tv_sec
276	mov r10 = r0
277	movl r2 = 1000000000
278	add r23 = IA64_TIMESPEC_TV_NSEC_OFFSET, r31
279(p14)	movl r3 = 2361183241434822607	// Prep for / 1000 hack
280	;;
281.time_normalize:
282	mov r21 = r8
283	cmp.ge p6,p0 = r8,r2
284(p14)	shr.u r20 = r8, 3 // We can repeat this if necessary just wasting time
285	;;
286(p14)	setf.sig f8 = r20
287(p6)	sub r8 = r8,r2
288(p6)	add r9 = 1,r9		// two nops before the branch.
289(p14)	setf.sig f7 = r3	// Chances for repeats are 1 in 10000 for gettod
290(p6)	br.cond.dpnt.few .time_normalize
291	;;
292	// Divided by 8 though shift. Now divide by 125
293	// The compiler was able to do that with a multiply
294	// and a shift and we do the same
295EX(.fail_efault, probe.w.fault r23, 3)	// This also costs 5 cycles
296(p14)	xmpy.hu f8 = f8, f7		// xmpy has 5 cycles latency so use it
297	;;
298(p14)	getf.sig r2 = f8
299	;;
300	mov r8 = r0
301(p14)	shr.u r21 = r2, 4
302	;;
303EX(.fail_efault, st8 [r31] = r9)
304EX(.fail_efault, st8 [r23] = r21)
305	FSYS_RETURN
306.fail_einval:
307	mov r8 = EINVAL
308	mov r10 = -1
309	FSYS_RETURN
310.fail_efault:
311	mov r8 = EFAULT
312	mov r10 = -1
313	FSYS_RETURN
314END(fsys_gettimeofday)
315
316ENTRY(fsys_clock_gettime)
317	.prologue
318	.altrp b6
319	.body
320	cmp4.ltu p6, p0 = CLOCK_MONOTONIC, r32
321	// Fallback if this is not CLOCK_REALTIME or CLOCK_MONOTONIC
322(p6)	br.spnt.few fsys_fallback_syscall
323	mov r31 = r33
324	shl r30 = r32,15
325	br.many .gettime
326END(fsys_clock_gettime)
327
328/*
329 * fsys_getcpu doesn't use the third parameter in this implementation. It reads
330 * current_thread_info()->cpu and corresponding node in cpu_to_node_map.
331 */
332ENTRY(fsys_getcpu)
333	.prologue
334	.altrp b6
335	.body
336	;;
337	add r2=TI_FLAGS+IA64_TASK_SIZE,r16
338	tnat.nz p6,p0 = r32			// guard against NaT argument
339	add r3=TI_CPU+IA64_TASK_SIZE,r16
340	;;
341	ld4 r3=[r3]				// M r3 = thread_info->cpu
342	ld4 r2=[r2]				// M r2 = thread_info->flags
343(p6)    br.cond.spnt.few .fail_einval		// B
344	;;
345	tnat.nz p7,p0 = r33			// I guard against NaT argument
346(p7)    br.cond.spnt.few .fail_einval		// B
347	;;
348	cmp.ne p6,p0=r32,r0
349	cmp.ne p7,p0=r33,r0
350	;;
351#ifdef CONFIG_NUMA
352	movl r17=cpu_to_node_map
353	;;
354EX(.fail_efault, (p6) probe.w.fault r32, 3)		// M This takes 5 cycles
355EX(.fail_efault, (p7) probe.w.fault r33, 3)		// M This takes 5 cycles
356	shladd r18=r3,1,r17
357	;;
358	ld2 r20=[r18]				// r20 = cpu_to_node_map[cpu]
359	and r2 = TIF_ALLWORK_MASK,r2
360	;;
361	cmp.ne p8,p0=0,r2
362(p8)	br.spnt.many fsys_fallback_syscall
363	;;
364	;;
365EX(.fail_efault, (p6) st4 [r32] = r3)
366EX(.fail_efault, (p7) st2 [r33] = r20)
367	mov r8=0
368	;;
369#else
370EX(.fail_efault, (p6) probe.w.fault r32, 3)		// M This takes 5 cycles
371EX(.fail_efault, (p7) probe.w.fault r33, 3)		// M This takes 5 cycles
372	and r2 = TIF_ALLWORK_MASK,r2
373	;;
374	cmp.ne p8,p0=0,r2
375(p8)	br.spnt.many fsys_fallback_syscall
376	;;
377EX(.fail_efault, (p6) st4 [r32] = r3)
378EX(.fail_efault, (p7) st2 [r33] = r0)
379	mov r8=0
380	;;
381#endif
382	FSYS_RETURN
383END(fsys_getcpu)
384
385ENTRY(fsys_fallback_syscall)
386	.prologue
387	.altrp b6
388	.body
389	/*
390	 * We only get here from light-weight syscall handlers.  Thus, we already
391	 * know that r15 contains a valid syscall number.  No need to re-check.
392	 */
393	adds r17=-1024,r15
394	movl r14=sys_call_table
395	;;
396	RSM_PSR_I(p0, r26, r27)
397	shladd r18=r17,3,r14
398	;;
399	ld8 r18=[r18]				// load normal (heavy-weight) syscall entry-point
400	MOV_FROM_PSR(p0, r29, r26)		// read psr (12 cyc load latency)
401	mov r27=ar.rsc
402	mov r21=ar.fpsr
403	mov r26=ar.pfs
404END(fsys_fallback_syscall)
405	/* FALL THROUGH */
406GLOBAL_ENTRY(fsys_bubble_down)
407	.prologue
408	.altrp b6
409	.body
410	/*
411	 * We get here for syscalls that don't have a lightweight
412	 * handler.  For those, we need to bubble down into the kernel
413	 * and that requires setting up a minimal pt_regs structure,
414	 * and initializing the CPU state more or less as if an
415	 * interruption had occurred.  To make syscall-restarts work,
416	 * we setup pt_regs such that cr_iip points to the second
417	 * instruction in syscall_via_break.  Decrementing the IP
418	 * hence will restart the syscall via break and not
419	 * decrementing IP will return us to the caller, as usual.
420	 * Note that we preserve the value of psr.pp rather than
421	 * initializing it from dcr.pp.  This makes it possible to
422	 * distinguish fsyscall execution from other privileged
423	 * execution.
424	 *
425	 * On entry:
426	 *	- normal fsyscall handler register usage, except
427	 *	  that we also have:
428	 *	- r18: address of syscall entry point
429	 *	- r21: ar.fpsr
430	 *	- r26: ar.pfs
431	 *	- r27: ar.rsc
432	 *	- r29: psr
433	 *
434	 * We used to clear some PSR bits here but that requires slow
435	 * serialization.  Fortunately, that isn't really necessary.
436	 * The rationale is as follows: we used to clear bits
437	 * ~PSR_PRESERVED_BITS in PSR.L.  Since
438	 * PSR_PRESERVED_BITS==PSR.{UP,MFL,MFH,PK,DT,PP,SP,RT,IC}, we
439	 * ended up clearing PSR.{BE,AC,I,DFL,DFH,DI,DB,SI,TB}.
440	 * However,
441	 *
442	 * PSR.BE : already is turned off in __kernel_syscall_via_epc()
443	 * PSR.AC : don't care (kernel normally turns PSR.AC on)
444	 * PSR.I  : already turned off by the time fsys_bubble_down gets
445	 *	    invoked
446	 * PSR.DFL: always 0 (kernel never turns it on)
447	 * PSR.DFH: don't care --- kernel never touches f32-f127 on its own
448	 *	    initiative
449	 * PSR.DI : always 0 (kernel never turns it on)
450	 * PSR.SI : always 0 (kernel never turns it on)
451	 * PSR.DB : don't care --- kernel never enables kernel-level
452	 *	    breakpoints
453	 * PSR.TB : must be 0 already; if it wasn't zero on entry to
454	 *          __kernel_syscall_via_epc, the branch to fsys_bubble_down
455	 *          will trigger a taken branch; the taken-trap-handler then
456	 *          converts the syscall into a break-based system-call.
457	 */
458	/*
459	 * Reading psr.l gives us only bits 0-31, psr.it, and psr.mc.
460	 * The rest we have to synthesize.
461	 */
462#	define PSR_ONE_BITS		((3 << IA64_PSR_CPL0_BIT)	\
463					 | (0x1 << IA64_PSR_RI_BIT)	\
464					 | IA64_PSR_BN | IA64_PSR_I)
465
466	invala					// M0|1
467	movl r14=ia64_ret_from_syscall		// X
468
469	nop.m 0
470	movl r28=__kernel_syscall_via_break	// X	create cr.iip
471	;;
472
473	mov r2=r16				// A    get task addr to addl-addressable register
474	adds r16=IA64_TASK_THREAD_ON_USTACK_OFFSET,r16 // A
475	mov r31=pr				// I0   save pr (2 cyc)
476	;;
477	st1 [r16]=r0				// M2|3 clear current->thread.on_ustack flag
478	addl r22=IA64_RBS_OFFSET,r2		// A    compute base of RBS
479	add r3=TI_FLAGS+IA64_TASK_SIZE,r2	// A
480	;;
481	ld4 r3=[r3]				// M0|1 r3 = current_thread_info()->flags
482	lfetch.fault.excl.nt1 [r22]		// M0|1 prefetch register backing-store
483	nop.i 0
484	;;
485	mov ar.rsc=0				// M2   set enforced lazy mode, pl 0, LE, loadrs=0
486#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
487	MOV_FROM_ITC(p0, p6, r30, r23)		// M    get cycle for accounting
488#else
489	nop.m 0
490#endif
491	nop.i 0
492	;;
493	mov r23=ar.bspstore			// M2 (12 cyc) save ar.bspstore
494	mov.m r24=ar.rnat			// M2 (5 cyc) read ar.rnat (dual-issues!)
495	nop.i 0
496	;;
497	mov ar.bspstore=r22			// M2 (6 cyc) switch to kernel RBS
498	movl r8=PSR_ONE_BITS			// X
499	;;
500	mov r25=ar.unat				// M2 (5 cyc) save ar.unat
501	mov r19=b6				// I0   save b6 (2 cyc)
502	mov r20=r1				// A    save caller's gp in r20
503	;;
504	or r29=r8,r29				// A    construct cr.ipsr value to save
505	mov b6=r18				// I0   copy syscall entry-point to b6 (7 cyc)
506	addl r1=IA64_STK_OFFSET-IA64_PT_REGS_SIZE,r2 // A compute base of memory stack
507
508	mov r18=ar.bsp				// M2   save (kernel) ar.bsp (12 cyc)
509	cmp.ne pKStk,pUStk=r0,r0		// A    set pKStk <- 0, pUStk <- 1
510	br.call.sptk.many b7=ia64_syscall_setup	// B
511	;;
512#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
513	// mov.m r30=ar.itc is called in advance
514	add r16=TI_AC_STAMP+IA64_TASK_SIZE,r2
515	add r17=TI_AC_LEAVE+IA64_TASK_SIZE,r2
516	;;
517	ld8 r18=[r16],TI_AC_STIME-TI_AC_STAMP	// time at last check in kernel
518	ld8 r19=[r17],TI_AC_UTIME-TI_AC_LEAVE	// time at leave kernel
519	;;
520	ld8 r20=[r16],TI_AC_STAMP-TI_AC_STIME	// cumulated stime
521	ld8 r21=[r17]				// cumulated utime
522	sub r22=r19,r18				// stime before leave kernel
523	;;
524	st8 [r16]=r30,TI_AC_STIME-TI_AC_STAMP	// update stamp
525	sub r18=r30,r19				// elapsed time in user mode
526	;;
527	add r20=r20,r22				// sum stime
528	add r21=r21,r18				// sum utime
529	;;
530	st8 [r16]=r20				// update stime
531	st8 [r17]=r21				// update utime
532	;;
533#endif
534	mov ar.rsc=0x3				// M2   set eager mode, pl 0, LE, loadrs=0
535	mov rp=r14				// I0   set the real return addr
536	and r3=_TIF_SYSCALL_TRACEAUDIT,r3	// A
537	;;
538	SSM_PSR_I(p0, p6, r22)			// M2   we're on kernel stacks now, reenable irqs
539	cmp.eq p8,p0=r3,r0			// A
540(p10)	br.cond.spnt.many ia64_ret_from_syscall	// B    return if bad call-frame or r15 is a NaT
541
542	nop.m 0
543(p8)	br.call.sptk.many b6=b6			// B    (ignore return address)
544	br.cond.spnt ia64_trace_syscall		// B
545END(fsys_bubble_down)
546
547	.rodata
548	.align 8
549	.globl fsyscall_table
550
551	data8 fsys_bubble_down
552fsyscall_table:
553	data8 fsys_ni_syscall
554	data8 0				// exit			// 1025
555	data8 0				// read
556	data8 0				// write
557	data8 0				// open
558	data8 0				// close
559	data8 0				// creat		// 1030
560	data8 0				// link
561	data8 0				// unlink
562	data8 0				// execve
563	data8 0				// chdir
564	data8 0				// fchdir		// 1035
565	data8 0				// utimes
566	data8 0				// mknod
567	data8 0				// chmod
568	data8 0				// chown
569	data8 0				// lseek		// 1040
570	data8 fsys_getpid		// getpid
571	data8 0				// getppid
572	data8 0				// mount
573	data8 0				// umount
574	data8 0				// setuid		// 1045
575	data8 0				// getuid
576	data8 0				// geteuid
577	data8 0				// ptrace
578	data8 0				// access
579	data8 0				// sync			// 1050
580	data8 0				// fsync
581	data8 0				// fdatasync
582	data8 0				// kill
583	data8 0				// rename
584	data8 0				// mkdir		// 1055
585	data8 0				// rmdir
586	data8 0				// dup
587	data8 0				// pipe
588	data8 0				// times
589	data8 0				// brk			// 1060
590	data8 0				// setgid
591	data8 0				// getgid
592	data8 0				// getegid
593	data8 0				// acct
594	data8 0				// ioctl		// 1065
595	data8 0				// fcntl
596	data8 0				// umask
597	data8 0				// chroot
598	data8 0				// ustat
599	data8 0				// dup2			// 1070
600	data8 0				// setreuid
601	data8 0				// setregid
602	data8 0				// getresuid
603	data8 0				// setresuid
604	data8 0				// getresgid		// 1075
605	data8 0				// setresgid
606	data8 0				// getgroups
607	data8 0				// setgroups
608	data8 0				// getpgid
609	data8 0				// setpgid		// 1080
610	data8 0				// setsid
611	data8 0				// getsid
612	data8 0				// sethostname
613	data8 0				// setrlimit
614	data8 0				// getrlimit		// 1085
615	data8 0				// getrusage
616	data8 fsys_gettimeofday		// gettimeofday
617	data8 0				// settimeofday
618	data8 0				// select
619	data8 0				// poll			// 1090
620	data8 0				// symlink
621	data8 0				// readlink
622	data8 0				// uselib
623	data8 0				// swapon
624	data8 0				// swapoff		// 1095
625	data8 0				// reboot
626	data8 0				// truncate
627	data8 0				// ftruncate
628	data8 0				// fchmod
629	data8 0				// fchown		// 1100
630	data8 0				// getpriority
631	data8 0				// setpriority
632	data8 0				// statfs
633	data8 0				// fstatfs
634	data8 0				// gettid		// 1105
635	data8 0				// semget
636	data8 0				// semop
637	data8 0				// semctl
638	data8 0				// msgget
639	data8 0				// msgsnd		// 1110
640	data8 0				// msgrcv
641	data8 0				// msgctl
642	data8 0				// shmget
643	data8 0				// shmat
644	data8 0				// shmdt		// 1115
645	data8 0				// shmctl
646	data8 0				// syslog
647	data8 0				// setitimer
648	data8 0				// getitimer
649	data8 0					 		// 1120
650	data8 0
651	data8 0
652	data8 0				// vhangup
653	data8 0				// lchown
654	data8 0				// remap_file_pages	// 1125
655	data8 0				// wait4
656	data8 0				// sysinfo
657	data8 0				// clone
658	data8 0				// setdomainname
659	data8 0				// newuname		// 1130
660	data8 0				// adjtimex
661	data8 0
662	data8 0				// init_module
663	data8 0				// delete_module
664	data8 0							// 1135
665	data8 0
666	data8 0				// quotactl
667	data8 0				// bdflush
668	data8 0				// sysfs
669	data8 0				// personality		// 1140
670	data8 0				// afs_syscall
671	data8 0				// setfsuid
672	data8 0				// setfsgid
673	data8 0				// getdents
674	data8 0				// flock		// 1145
675	data8 0				// readv
676	data8 0				// writev
677	data8 0				// pread64
678	data8 0				// pwrite64
679	data8 0				// sysctl		// 1150
680	data8 0				// mmap
681	data8 0				// munmap
682	data8 0				// mlock
683	data8 0				// mlockall
684	data8 0				// mprotect		// 1155
685	data8 0				// mremap
686	data8 0				// msync
687	data8 0				// munlock
688	data8 0				// munlockall
689	data8 0				// sched_getparam	// 1160
690	data8 0				// sched_setparam
691	data8 0				// sched_getscheduler
692	data8 0				// sched_setscheduler
693	data8 0				// sched_yield
694	data8 0				// sched_get_priority_max	// 1165
695	data8 0				// sched_get_priority_min
696	data8 0				// sched_rr_get_interval
697	data8 0				// nanosleep
698	data8 0				// nfsservctl
699	data8 0				// prctl		// 1170
700	data8 0				// getpagesize
701	data8 0				// mmap2
702	data8 0				// pciconfig_read
703	data8 0				// pciconfig_write
704	data8 0				// perfmonctl		// 1175
705	data8 0				// sigaltstack
706	data8 0				// rt_sigaction
707	data8 0				// rt_sigpending
708	data8 0				// rt_sigprocmask
709	data8 0				// rt_sigqueueinfo	// 1180
710	data8 0				// rt_sigreturn
711	data8 0				// rt_sigsuspend
712	data8 0				// rt_sigtimedwait
713	data8 0				// getcwd
714	data8 0				// capget		// 1185
715	data8 0				// capset
716	data8 0				// sendfile
717	data8 0
718	data8 0
719	data8 0				// socket		// 1190
720	data8 0				// bind
721	data8 0				// connect
722	data8 0				// listen
723	data8 0				// accept
724	data8 0				// getsockname		// 1195
725	data8 0				// getpeername
726	data8 0				// socketpair
727	data8 0				// send
728	data8 0				// sendto
729	data8 0				// recv			// 1200
730	data8 0				// recvfrom
731	data8 0				// shutdown
732	data8 0				// setsockopt
733	data8 0				// getsockopt
734	data8 0				// sendmsg		// 1205
735	data8 0				// recvmsg
736	data8 0				// pivot_root
737	data8 0				// mincore
738	data8 0				// madvise
739	data8 0				// newstat		// 1210
740	data8 0				// newlstat
741	data8 0				// newfstat
742	data8 0				// clone2
743	data8 0				// getdents64
744	data8 0				// getunwind		// 1215
745	data8 0				// readahead
746	data8 0				// setxattr
747	data8 0				// lsetxattr
748	data8 0				// fsetxattr
749	data8 0				// getxattr		// 1220
750	data8 0				// lgetxattr
751	data8 0				// fgetxattr
752	data8 0				// listxattr
753	data8 0				// llistxattr
754	data8 0				// flistxattr		// 1225
755	data8 0				// removexattr
756	data8 0				// lremovexattr
757	data8 0				// fremovexattr
758	data8 0				// tkill
759	data8 0				// futex		// 1230
760	data8 0				// sched_setaffinity
761	data8 0				// sched_getaffinity
762	data8 fsys_set_tid_address	// set_tid_address
763	data8 0				// fadvise64_64
764	data8 0				// tgkill		// 1235
765	data8 0				// exit_group
766	data8 0				// lookup_dcookie
767	data8 0				// io_setup
768	data8 0				// io_destroy
769	data8 0				// io_getevents		// 1240
770	data8 0				// io_submit
771	data8 0				// io_cancel
772	data8 0				// epoll_create
773	data8 0				// epoll_ctl
774	data8 0				// epoll_wait		// 1245
775	data8 0				// restart_syscall
776	data8 0				// semtimedop
777	data8 0				// timer_create
778	data8 0				// timer_settime
779	data8 0				// timer_gettime 	// 1250
780	data8 0				// timer_getoverrun
781	data8 0				// timer_delete
782	data8 0				// clock_settime
783	data8 fsys_clock_gettime	// clock_gettime
784	data8 0				// clock_getres		// 1255
785	data8 0				// clock_nanosleep
786	data8 0				// fstatfs64
787	data8 0				// statfs64
788	data8 0				// mbind
789	data8 0				// get_mempolicy	// 1260
790	data8 0				// set_mempolicy
791	data8 0				// mq_open
792	data8 0				// mq_unlink
793	data8 0				// mq_timedsend
794	data8 0				// mq_timedreceive	// 1265
795	data8 0				// mq_notify
796	data8 0				// mq_getsetattr
797	data8 0				// kexec_load
798	data8 0				// vserver
799	data8 0				// waitid		// 1270
800	data8 0				// add_key
801	data8 0				// request_key
802	data8 0				// keyctl
803	data8 0				// ioprio_set
804	data8 0				// ioprio_get		// 1275
805	data8 0				// move_pages
806	data8 0				// inotify_init
807	data8 0				// inotify_add_watch
808	data8 0				// inotify_rm_watch
809	data8 0				// migrate_pages	// 1280
810	data8 0				// openat
811	data8 0				// mkdirat
812	data8 0				// mknodat
813	data8 0				// fchownat
814	data8 0				// futimesat		// 1285
815	data8 0				// newfstatat
816	data8 0				// unlinkat
817	data8 0				// renameat
818	data8 0				// linkat
819	data8 0				// symlinkat		// 1290
820	data8 0				// readlinkat
821	data8 0				// fchmodat
822	data8 0				// faccessat
823	data8 0
824	data8 0							// 1295
825	data8 0				// unshare
826	data8 0				// splice
827	data8 0				// set_robust_list
828	data8 0				// get_robust_list
829	data8 0				// sync_file_range	// 1300
830	data8 0				// tee
831	data8 0				// vmsplice
832	data8 0
833	data8 fsys_getcpu		// getcpu		// 1304
834
835	// fill in zeros for the remaining entries
836	.zero:
837	.space fsyscall_table + 8*NR_syscalls - .zero, 0
v3.5.6
 
  1/*
  2 * This file contains the light-weight system call handlers (fsyscall-handlers).
  3 *
  4 * Copyright (C) 2003 Hewlett-Packard Co
  5 * 	David Mosberger-Tang <davidm@hpl.hp.com>
  6 *
  7 * 25-Sep-03 davidm	Implement fsys_rt_sigprocmask().
  8 * 18-Feb-03 louisk	Implement fsys_gettimeofday().
  9 * 28-Feb-03 davidm	Fixed several bugs in fsys_gettimeofday().  Tuned it some more,
 10 *			probably broke it along the way... ;-)
 11 * 13-Jul-04 clameter   Implement fsys_clock_gettime and revise fsys_gettimeofday to make
 12 *                      it capable of using memory based clocks without falling back to C code.
 13 * 08-Feb-07 Fenghua Yu Implement fsys_getcpu.
 14 *
 15 */
 16
 17#include <asm/asmmacro.h>
 18#include <asm/errno.h>
 19#include <asm/asm-offsets.h>
 20#include <asm/percpu.h>
 21#include <asm/thread_info.h>
 22#include <asm/sal.h>
 23#include <asm/signal.h>
 24#include <asm/unistd.h>
 25
 26#include "entry.h"
 27#include "paravirt_inst.h"
 28
 29/*
 30 * See Documentation/ia64/fsys.txt for details on fsyscalls.
 31 *
 32 * On entry to an fsyscall handler:
 33 *   r10	= 0 (i.e., defaults to "successful syscall return")
 34 *   r11	= saved ar.pfs (a user-level value)
 35 *   r15	= system call number
 36 *   r16	= "current" task pointer (in normal kernel-mode, this is in r13)
 37 *   r32-r39	= system call arguments
 38 *   b6		= return address (a user-level value)
 39 *   ar.pfs	= previous frame-state (a user-level value)
 40 *   PSR.be	= cleared to zero (i.e., little-endian byte order is in effect)
 41 *   all other registers may contain values passed in from user-mode
 42 *
 43 * On return from an fsyscall handler:
 44 *   r11	= saved ar.pfs (as passed into the fsyscall handler)
 45 *   r15	= system call number (as passed into the fsyscall handler)
 46 *   r32-r39	= system call arguments (as passed into the fsyscall handler)
 47 *   b6		= return address (as passed into the fsyscall handler)
 48 *   ar.pfs	= previous frame-state (as passed into the fsyscall handler)
 49 */
 50
 51ENTRY(fsys_ni_syscall)
 52	.prologue
 53	.altrp b6
 54	.body
 55	mov r8=ENOSYS
 56	mov r10=-1
 57	FSYS_RETURN
 58END(fsys_ni_syscall)
 59
 60ENTRY(fsys_getpid)
 61	.prologue
 62	.altrp b6
 63	.body
 64	add r17=IA64_TASK_GROUP_LEADER_OFFSET,r16
 65	;;
 66	ld8 r17=[r17]				// r17 = current->group_leader
 67	add r9=TI_FLAGS+IA64_TASK_SIZE,r16
 68	;;
 69	ld4 r9=[r9]
 70	add r17=IA64_TASK_TGIDLINK_OFFSET,r17
 71	;;
 72	and r9=TIF_ALLWORK_MASK,r9
 73	ld8 r17=[r17]				// r17 = current->group_leader->pids[PIDTYPE_PID].pid
 74	;;
 75	add r8=IA64_PID_LEVEL_OFFSET,r17
 76	;;
 77	ld4 r8=[r8]				// r8 = pid->level
 78	add r17=IA64_PID_UPID_OFFSET,r17	// r17 = &pid->numbers[0]
 79	;;
 80	shl r8=r8,IA64_UPID_SHIFT
 81	;;
 82	add r17=r17,r8				// r17 = &pid->numbers[pid->level]
 83	;;
 84	ld4 r8=[r17]				// r8 = pid->numbers[pid->level].nr
 85	;;
 86	mov r17=0
 87	;;
 88	cmp.ne p8,p0=0,r9
 89(p8)	br.spnt.many fsys_fallback_syscall
 90	FSYS_RETURN
 91END(fsys_getpid)
 92
 93ENTRY(fsys_getppid)
 94	.prologue
 95	.altrp b6
 96	.body
 97	add r17=IA64_TASK_GROUP_LEADER_OFFSET,r16
 98	;;
 99	ld8 r17=[r17]				// r17 = current->group_leader
100	add r9=TI_FLAGS+IA64_TASK_SIZE,r16
101	;;
102
103	ld4 r9=[r9]
104	add r17=IA64_TASK_REAL_PARENT_OFFSET,r17 // r17 = &current->group_leader->real_parent
105	;;
106	and r9=TIF_ALLWORK_MASK,r9
107
1081:	ld8 r18=[r17]				// r18 = current->group_leader->real_parent
109	;;
110	cmp.ne p8,p0=0,r9
111	add r8=IA64_TASK_TGID_OFFSET,r18	// r8 = &current->group_leader->real_parent->tgid
112	;;
113
114	/*
115	 * The .acq is needed to ensure that the read of tgid has returned its data before
116	 * we re-check "real_parent".
117	 */
118	ld4.acq r8=[r8]				// r8 = current->group_leader->real_parent->tgid
119#ifdef CONFIG_SMP
120	/*
121	 * Re-read current->group_leader->real_parent.
122	 */
123	ld8 r19=[r17]				// r19 = current->group_leader->real_parent
124(p8)	br.spnt.many fsys_fallback_syscall
125	;;
126	cmp.ne p6,p0=r18,r19			// did real_parent change?
127	mov r19=0			// i must not leak kernel bits...
128(p6)	br.cond.spnt.few 1b			// yes -> redo the read of tgid and the check
129	;;
130	mov r17=0			// i must not leak kernel bits...
131	mov r18=0			// i must not leak kernel bits...
132#else
133	mov r17=0			// i must not leak kernel bits...
134	mov r18=0			// i must not leak kernel bits...
135	mov r19=0			// i must not leak kernel bits...
136#endif
137	FSYS_RETURN
138END(fsys_getppid)
139
140ENTRY(fsys_set_tid_address)
141	.prologue
142	.altrp b6
143	.body
144	add r9=TI_FLAGS+IA64_TASK_SIZE,r16
145	add r17=IA64_TASK_TGIDLINK_OFFSET,r16
146	;;
147	ld4 r9=[r9]
148	tnat.z p6,p7=r32		// check argument register for being NaT
149	ld8 r17=[r17]				// r17 = current->pids[PIDTYPE_PID].pid
150	;;
151	and r9=TIF_ALLWORK_MASK,r9
152	add r8=IA64_PID_LEVEL_OFFSET,r17
153	add r18=IA64_TASK_CLEAR_CHILD_TID_OFFSET,r16
154	;;
155	ld4 r8=[r8]				// r8 = pid->level
156	add r17=IA64_PID_UPID_OFFSET,r17	// r17 = &pid->numbers[0]
157	;;
158	shl r8=r8,IA64_UPID_SHIFT
159	;;
160	add r17=r17,r8				// r17 = &pid->numbers[pid->level]
161	;;
162	ld4 r8=[r17]				// r8 = pid->numbers[pid->level].nr
163	;;
164	cmp.ne p8,p0=0,r9
165	mov r17=-1
166	;;
167(p6)	st8 [r18]=r32
168(p7)	st8 [r18]=r17
169(p8)	br.spnt.many fsys_fallback_syscall
170	;;
171	mov r17=0			// i must not leak kernel bits...
172	mov r18=0			// i must not leak kernel bits...
173	FSYS_RETURN
174END(fsys_set_tid_address)
175
176#if IA64_GTOD_SEQ_OFFSET !=0
177#error fsys_gettimeofday incompatible with changes to struct fsyscall_gtod_data_t
178#endif
179#if IA64_ITC_JITTER_OFFSET !=0
180#error fsys_gettimeofday incompatible with changes to struct itc_jitter_data_t
181#endif
182#define CLOCK_REALTIME 0
183#define CLOCK_MONOTONIC 1
184#define CLOCK_DIVIDE_BY_1000 0x4000
185#define CLOCK_ADD_MONOTONIC 0x8000
186
187ENTRY(fsys_gettimeofday)
188	.prologue
189	.altrp b6
190	.body
191	mov r31 = r32
192	tnat.nz p6,p0 = r33		// guard against NaT argument
193(p6)    br.cond.spnt.few .fail_einval
194	mov r30 = CLOCK_DIVIDE_BY_1000
195	;;
196.gettime:
197	// Register map
198	// Incoming r31 = pointer to address where to place result
199	//          r30 = flags determining how time is processed
200	// r2,r3 = temp r4-r7 preserved
201	// r8 = result nanoseconds
202	// r9 = result seconds
203	// r10 = temporary storage for clock difference
204	// r11 = preserved: saved ar.pfs
205	// r12 = preserved: memory stack
206	// r13 = preserved: thread pointer
207	// r14 = address of mask / mask value
208	// r15 = preserved: system call number
209	// r16 = preserved: current task pointer
210	// r17 = (not used)
211	// r18 = (not used)
212	// r19 = address of itc_lastcycle
213	// r20 = struct fsyscall_gtod_data (= address of gtod_lock.sequence)
214	// r21 = address of mmio_ptr
215	// r22 = address of wall_time or monotonic_time
216	// r23 = address of shift / value
217	// r24 = address mult factor / cycle_last value
218	// r25 = itc_lastcycle value
219	// r26 = address clocksource cycle_last
220	// r27 = (not used)
221	// r28 = sequence number at the beginning of critcal section
222	// r29 = address of itc_jitter
223	// r30 = time processing flags / memory address
224	// r31 = pointer to result
225	// Predicates
226	// p6,p7 short term use
227	// p8 = timesource ar.itc
228	// p9 = timesource mmio64
229	// p10 = timesource mmio32 - not used
230	// p11 = timesource not to be handled by asm code
231	// p12 = memory time source ( = p9 | p10) - not used
232	// p13 = do cmpxchg with itc_lastcycle
233	// p14 = Divide by 1000
234	// p15 = Add monotonic
235	//
236	// Note that instructions are optimized for McKinley. McKinley can
237	// process two bundles simultaneously and therefore we continuously
238	// try to feed the CPU two bundles and then a stop.
239
240	add r2 = TI_FLAGS+IA64_TASK_SIZE,r16
241	tnat.nz p6,p0 = r31		// guard against Nat argument
242(p6)	br.cond.spnt.few .fail_einval
243	movl r20 = fsyscall_gtod_data // load fsyscall gettimeofday data address
244	;;
245	ld4 r2 = [r2]			// process work pending flags
246	movl r29 = itc_jitter_data	// itc_jitter
247	add r22 = IA64_GTOD_WALL_TIME_OFFSET,r20	// wall_time
248	add r21 = IA64_CLKSRC_MMIO_OFFSET,r20
249	mov pr = r30,0xc000	// Set predicates according to function
250	;;
251	and r2 = TIF_ALLWORK_MASK,r2
252	add r19 = IA64_ITC_LASTCYCLE_OFFSET,r29
253(p15)	add r22 = IA64_GTOD_MONO_TIME_OFFSET,r20	// monotonic_time
254	;;
255	add r26 = IA64_CLKSRC_CYCLE_LAST_OFFSET,r20	// clksrc_cycle_last
256	cmp.ne p6, p0 = 0, r2	// Fallback if work is scheduled
257(p6)	br.cond.spnt.many fsys_fallback_syscall
258	;;
259	// Begin critical section
260.time_redo:
261	ld4.acq r28 = [r20]	// gtod_lock.sequence, Must take first
262	;;
263	and r28 = ~1,r28	// And make sequence even to force retry if odd
264	;;
265	ld8 r30 = [r21]		// clocksource->mmio_ptr
266	add r24 = IA64_CLKSRC_MULT_OFFSET,r20
267	ld4 r2 = [r29]		// itc_jitter value
268	add r23 = IA64_CLKSRC_SHIFT_OFFSET,r20
269	add r14 = IA64_CLKSRC_MASK_OFFSET,r20
270	;;
271	ld4 r3 = [r24]		// clocksource mult value
272	ld8 r14 = [r14]         // clocksource mask value
273	cmp.eq p8,p9 = 0,r30	// use cpu timer if no mmio_ptr
274	;;
275	setf.sig f7 = r3	// Setup for mult scaling of counter
276(p8)	cmp.ne p13,p0 = r2,r0	// need itc_jitter compensation, set p13
277	ld4 r23 = [r23]		// clocksource shift value
278	ld8 r24 = [r26]		// get clksrc_cycle_last value
279(p9)	cmp.eq p13,p0 = 0,r30	// if mmio_ptr, clear p13 jitter control
280	;;
281	.pred.rel.mutex p8,p9
282	MOV_FROM_ITC(p8, p6, r2, r10)	// CPU_TIMER. 36 clocks latency!!!
283(p9)	ld8 r2 = [r30]		// MMIO_TIMER. Could also have latency issues..
284(p13)	ld8 r25 = [r19]		// get itc_lastcycle value
285	ld8 r9 = [r22],IA64_TIMESPEC_TV_NSEC_OFFSET	// tv_sec
286	;;
287	ld8 r8 = [r22],-IA64_TIMESPEC_TV_NSEC_OFFSET	// tv_nsec
288(p13)	sub r3 = r25,r2		// Diff needed before comparison (thanks davidm)
289	;;
290(p13)	cmp.gt.unc p6,p7 = r3,r0 // check if it is less than last. p6,p7 cleared
291	sub r10 = r2,r24	// current_cycle - last_cycle
292	;;
293(p6)	sub r10 = r25,r24	// time we got was less than last_cycle
294(p7)	mov ar.ccv = r25	// more than last_cycle. Prep for cmpxchg
295	;;
296(p7)	cmpxchg8.rel r3 = [r19],r2,ar.ccv
297	;;
298(p7)	cmp.ne p7,p0 = r25,r3	// if cmpxchg not successful
299	;;
300(p7)	sub r10 = r3,r24	// then use new last_cycle instead
301	;;
302	and r10 = r10,r14	// Apply mask
303	;;
304	setf.sig f8 = r10
305	nop.i 123
306	;;
307	// fault check takes 5 cycles and we have spare time
308EX(.fail_efault, probe.w.fault r31, 3)
309	xmpy.l f8 = f8,f7	// nsec_per_cyc*(counter-last_counter)
310	;;
311	getf.sig r2 = f8
312	mf
313	;;
314	ld4 r10 = [r20]		// gtod_lock.sequence
315	shr.u r2 = r2,r23	// shift by factor
316	;;
317	add r8 = r8,r2		// Add xtime.nsecs
318	cmp4.ne p7,p0 = r28,r10
319(p7)	br.cond.dpnt.few .time_redo	// sequence number changed, redo
320	// End critical section.
321	// Now r8=tv->tv_nsec and r9=tv->tv_sec
322	mov r10 = r0
323	movl r2 = 1000000000
324	add r23 = IA64_TIMESPEC_TV_NSEC_OFFSET, r31
325(p14)	movl r3 = 2361183241434822607	// Prep for / 1000 hack
326	;;
327.time_normalize:
328	mov r21 = r8
329	cmp.ge p6,p0 = r8,r2
330(p14)	shr.u r20 = r8, 3 // We can repeat this if necessary just wasting time
331	;;
332(p14)	setf.sig f8 = r20
333(p6)	sub r8 = r8,r2
334(p6)	add r9 = 1,r9		// two nops before the branch.
335(p14)	setf.sig f7 = r3	// Chances for repeats are 1 in 10000 for gettod
336(p6)	br.cond.dpnt.few .time_normalize
337	;;
338	// Divided by 8 though shift. Now divide by 125
339	// The compiler was able to do that with a multiply
340	// and a shift and we do the same
341EX(.fail_efault, probe.w.fault r23, 3)	// This also costs 5 cycles
342(p14)	xmpy.hu f8 = f8, f7		// xmpy has 5 cycles latency so use it
343	;;
344(p14)	getf.sig r2 = f8
345	;;
346	mov r8 = r0
347(p14)	shr.u r21 = r2, 4
348	;;
349EX(.fail_efault, st8 [r31] = r9)
350EX(.fail_efault, st8 [r23] = r21)
351	FSYS_RETURN
352.fail_einval:
353	mov r8 = EINVAL
354	mov r10 = -1
355	FSYS_RETURN
356.fail_efault:
357	mov r8 = EFAULT
358	mov r10 = -1
359	FSYS_RETURN
360END(fsys_gettimeofday)
361
362ENTRY(fsys_clock_gettime)
363	.prologue
364	.altrp b6
365	.body
366	cmp4.ltu p6, p0 = CLOCK_MONOTONIC, r32
367	// Fallback if this is not CLOCK_REALTIME or CLOCK_MONOTONIC
368(p6)	br.spnt.few fsys_fallback_syscall
369	mov r31 = r33
370	shl r30 = r32,15
371	br.many .gettime
372END(fsys_clock_gettime)
373
374/*
375 * fsys_getcpu doesn't use the third parameter in this implementation. It reads
376 * current_thread_info()->cpu and corresponding node in cpu_to_node_map.
377 */
378ENTRY(fsys_getcpu)
379	.prologue
380	.altrp b6
381	.body
382	;;
383	add r2=TI_FLAGS+IA64_TASK_SIZE,r16
384	tnat.nz p6,p0 = r32			// guard against NaT argument
385	add r3=TI_CPU+IA64_TASK_SIZE,r16
386	;;
387	ld4 r3=[r3]				// M r3 = thread_info->cpu
388	ld4 r2=[r2]				// M r2 = thread_info->flags
389(p6)    br.cond.spnt.few .fail_einval		// B
390	;;
391	tnat.nz p7,p0 = r33			// I guard against NaT argument
392(p7)    br.cond.spnt.few .fail_einval		// B
393	;;
394	cmp.ne p6,p0=r32,r0
395	cmp.ne p7,p0=r33,r0
396	;;
397#ifdef CONFIG_NUMA
398	movl r17=cpu_to_node_map
399	;;
400EX(.fail_efault, (p6) probe.w.fault r32, 3)		// M This takes 5 cycles
401EX(.fail_efault, (p7) probe.w.fault r33, 3)		// M This takes 5 cycles
402	shladd r18=r3,1,r17
403	;;
404	ld2 r20=[r18]				// r20 = cpu_to_node_map[cpu]
405	and r2 = TIF_ALLWORK_MASK,r2
406	;;
407	cmp.ne p8,p0=0,r2
408(p8)	br.spnt.many fsys_fallback_syscall
409	;;
410	;;
411EX(.fail_efault, (p6) st4 [r32] = r3)
412EX(.fail_efault, (p7) st2 [r33] = r20)
413	mov r8=0
414	;;
415#else
416EX(.fail_efault, (p6) probe.w.fault r32, 3)		// M This takes 5 cycles
417EX(.fail_efault, (p7) probe.w.fault r33, 3)		// M This takes 5 cycles
418	and r2 = TIF_ALLWORK_MASK,r2
419	;;
420	cmp.ne p8,p0=0,r2
421(p8)	br.spnt.many fsys_fallback_syscall
422	;;
423EX(.fail_efault, (p6) st4 [r32] = r3)
424EX(.fail_efault, (p7) st2 [r33] = r0)
425	mov r8=0
426	;;
427#endif
428	FSYS_RETURN
429END(fsys_getcpu)
430
431ENTRY(fsys_fallback_syscall)
432	.prologue
433	.altrp b6
434	.body
435	/*
436	 * We only get here from light-weight syscall handlers.  Thus, we already
437	 * know that r15 contains a valid syscall number.  No need to re-check.
438	 */
439	adds r17=-1024,r15
440	movl r14=sys_call_table
441	;;
442	RSM_PSR_I(p0, r26, r27)
443	shladd r18=r17,3,r14
444	;;
445	ld8 r18=[r18]				// load normal (heavy-weight) syscall entry-point
446	MOV_FROM_PSR(p0, r29, r26)		// read psr (12 cyc load latency)
447	mov r27=ar.rsc
448	mov r21=ar.fpsr
449	mov r26=ar.pfs
450END(fsys_fallback_syscall)
451	/* FALL THROUGH */
452GLOBAL_ENTRY(paravirt_fsys_bubble_down)
453	.prologue
454	.altrp b6
455	.body
456	/*
457	 * We get here for syscalls that don't have a lightweight
458	 * handler.  For those, we need to bubble down into the kernel
459	 * and that requires setting up a minimal pt_regs structure,
460	 * and initializing the CPU state more or less as if an
461	 * interruption had occurred.  To make syscall-restarts work,
462	 * we setup pt_regs such that cr_iip points to the second
463	 * instruction in syscall_via_break.  Decrementing the IP
464	 * hence will restart the syscall via break and not
465	 * decrementing IP will return us to the caller, as usual.
466	 * Note that we preserve the value of psr.pp rather than
467	 * initializing it from dcr.pp.  This makes it possible to
468	 * distinguish fsyscall execution from other privileged
469	 * execution.
470	 *
471	 * On entry:
472	 *	- normal fsyscall handler register usage, except
473	 *	  that we also have:
474	 *	- r18: address of syscall entry point
475	 *	- r21: ar.fpsr
476	 *	- r26: ar.pfs
477	 *	- r27: ar.rsc
478	 *	- r29: psr
479	 *
480	 * We used to clear some PSR bits here but that requires slow
481	 * serialization.  Fortuntely, that isn't really necessary.
482	 * The rationale is as follows: we used to clear bits
483	 * ~PSR_PRESERVED_BITS in PSR.L.  Since
484	 * PSR_PRESERVED_BITS==PSR.{UP,MFL,MFH,PK,DT,PP,SP,RT,IC}, we
485	 * ended up clearing PSR.{BE,AC,I,DFL,DFH,DI,DB,SI,TB}.
486	 * However,
487	 *
488	 * PSR.BE : already is turned off in __kernel_syscall_via_epc()
489	 * PSR.AC : don't care (kernel normally turns PSR.AC on)
490	 * PSR.I  : already turned off by the time paravirt_fsys_bubble_down gets
491	 *	    invoked
492	 * PSR.DFL: always 0 (kernel never turns it on)
493	 * PSR.DFH: don't care --- kernel never touches f32-f127 on its own
494	 *	    initiative
495	 * PSR.DI : always 0 (kernel never turns it on)
496	 * PSR.SI : always 0 (kernel never turns it on)
497	 * PSR.DB : don't care --- kernel never enables kernel-level
498	 *	    breakpoints
499	 * PSR.TB : must be 0 already; if it wasn't zero on entry to
500	 *          __kernel_syscall_via_epc, the branch to paravirt_fsys_bubble_down
501	 *          will trigger a taken branch; the taken-trap-handler then
502	 *          converts the syscall into a break-based system-call.
503	 */
504	/*
505	 * Reading psr.l gives us only bits 0-31, psr.it, and psr.mc.
506	 * The rest we have to synthesize.
507	 */
508#	define PSR_ONE_BITS		((3 << IA64_PSR_CPL0_BIT)	\
509					 | (0x1 << IA64_PSR_RI_BIT)	\
510					 | IA64_PSR_BN | IA64_PSR_I)
511
512	invala					// M0|1
513	movl r14=ia64_ret_from_syscall		// X
514
515	nop.m 0
516	movl r28=__kernel_syscall_via_break	// X	create cr.iip
517	;;
518
519	mov r2=r16				// A    get task addr to addl-addressable register
520	adds r16=IA64_TASK_THREAD_ON_USTACK_OFFSET,r16 // A
521	mov r31=pr				// I0   save pr (2 cyc)
522	;;
523	st1 [r16]=r0				// M2|3 clear current->thread.on_ustack flag
524	addl r22=IA64_RBS_OFFSET,r2		// A    compute base of RBS
525	add r3=TI_FLAGS+IA64_TASK_SIZE,r2	// A
526	;;
527	ld4 r3=[r3]				// M0|1 r3 = current_thread_info()->flags
528	lfetch.fault.excl.nt1 [r22]		// M0|1 prefetch register backing-store
529	nop.i 0
530	;;
531	mov ar.rsc=0				// M2   set enforced lazy mode, pl 0, LE, loadrs=0
532#ifdef CONFIG_VIRT_CPU_ACCOUNTING
533	MOV_FROM_ITC(p0, p6, r30, r23)		// M    get cycle for accounting
534#else
535	nop.m 0
536#endif
537	nop.i 0
538	;;
539	mov r23=ar.bspstore			// M2 (12 cyc) save ar.bspstore
540	mov.m r24=ar.rnat			// M2 (5 cyc) read ar.rnat (dual-issues!)
541	nop.i 0
542	;;
543	mov ar.bspstore=r22			// M2 (6 cyc) switch to kernel RBS
544	movl r8=PSR_ONE_BITS			// X
545	;;
546	mov r25=ar.unat				// M2 (5 cyc) save ar.unat
547	mov r19=b6				// I0   save b6 (2 cyc)
548	mov r20=r1				// A    save caller's gp in r20
549	;;
550	or r29=r8,r29				// A    construct cr.ipsr value to save
551	mov b6=r18				// I0   copy syscall entry-point to b6 (7 cyc)
552	addl r1=IA64_STK_OFFSET-IA64_PT_REGS_SIZE,r2 // A compute base of memory stack
553
554	mov r18=ar.bsp				// M2   save (kernel) ar.bsp (12 cyc)
555	cmp.ne pKStk,pUStk=r0,r0		// A    set pKStk <- 0, pUStk <- 1
556	br.call.sptk.many b7=ia64_syscall_setup	// B
557	;;
558#ifdef CONFIG_VIRT_CPU_ACCOUNTING
559	// mov.m r30=ar.itc is called in advance
560	add r16=TI_AC_STAMP+IA64_TASK_SIZE,r2
561	add r17=TI_AC_LEAVE+IA64_TASK_SIZE,r2
562	;;
563	ld8 r18=[r16],TI_AC_STIME-TI_AC_STAMP	// time at last check in kernel
564	ld8 r19=[r17],TI_AC_UTIME-TI_AC_LEAVE	// time at leave kernel
565	;;
566	ld8 r20=[r16],TI_AC_STAMP-TI_AC_STIME	// cumulated stime
567	ld8 r21=[r17]				// cumulated utime
568	sub r22=r19,r18				// stime before leave kernel
569	;;
570	st8 [r16]=r30,TI_AC_STIME-TI_AC_STAMP	// update stamp
571	sub r18=r30,r19				// elapsed time in user mode
572	;;
573	add r20=r20,r22				// sum stime
574	add r21=r21,r18				// sum utime
575	;;
576	st8 [r16]=r20				// update stime
577	st8 [r17]=r21				// update utime
578	;;
579#endif
580	mov ar.rsc=0x3				// M2   set eager mode, pl 0, LE, loadrs=0
581	mov rp=r14				// I0   set the real return addr
582	and r3=_TIF_SYSCALL_TRACEAUDIT,r3	// A
583	;;
584	SSM_PSR_I(p0, p6, r22)			// M2   we're on kernel stacks now, reenable irqs
585	cmp.eq p8,p0=r3,r0			// A
586(p10)	br.cond.spnt.many ia64_ret_from_syscall	// B    return if bad call-frame or r15 is a NaT
587
588	nop.m 0
589(p8)	br.call.sptk.many b6=b6			// B    (ignore return address)
590	br.cond.spnt ia64_trace_syscall		// B
591END(paravirt_fsys_bubble_down)
592
593	.rodata
594	.align 8
595	.globl paravirt_fsyscall_table
596
597	data8 paravirt_fsys_bubble_down
598paravirt_fsyscall_table:
599	data8 fsys_ni_syscall
600	data8 0				// exit			// 1025
601	data8 0				// read
602	data8 0				// write
603	data8 0				// open
604	data8 0				// close
605	data8 0				// creat		// 1030
606	data8 0				// link
607	data8 0				// unlink
608	data8 0				// execve
609	data8 0				// chdir
610	data8 0				// fchdir		// 1035
611	data8 0				// utimes
612	data8 0				// mknod
613	data8 0				// chmod
614	data8 0				// chown
615	data8 0				// lseek		// 1040
616	data8 fsys_getpid		// getpid
617	data8 fsys_getppid		// getppid
618	data8 0				// mount
619	data8 0				// umount
620	data8 0				// setuid		// 1045
621	data8 0				// getuid
622	data8 0				// geteuid
623	data8 0				// ptrace
624	data8 0				// access
625	data8 0				// sync			// 1050
626	data8 0				// fsync
627	data8 0				// fdatasync
628	data8 0				// kill
629	data8 0				// rename
630	data8 0				// mkdir		// 1055
631	data8 0				// rmdir
632	data8 0				// dup
633	data8 0				// pipe
634	data8 0				// times
635	data8 0				// brk			// 1060
636	data8 0				// setgid
637	data8 0				// getgid
638	data8 0				// getegid
639	data8 0				// acct
640	data8 0				// ioctl		// 1065
641	data8 0				// fcntl
642	data8 0				// umask
643	data8 0				// chroot
644	data8 0				// ustat
645	data8 0				// dup2			// 1070
646	data8 0				// setreuid
647	data8 0				// setregid
648	data8 0				// getresuid
649	data8 0				// setresuid
650	data8 0				// getresgid		// 1075
651	data8 0				// setresgid
652	data8 0				// getgroups
653	data8 0				// setgroups
654	data8 0				// getpgid
655	data8 0				// setpgid		// 1080
656	data8 0				// setsid
657	data8 0				// getsid
658	data8 0				// sethostname
659	data8 0				// setrlimit
660	data8 0				// getrlimit		// 1085
661	data8 0				// getrusage
662	data8 fsys_gettimeofday		// gettimeofday
663	data8 0				// settimeofday
664	data8 0				// select
665	data8 0				// poll			// 1090
666	data8 0				// symlink
667	data8 0				// readlink
668	data8 0				// uselib
669	data8 0				// swapon
670	data8 0				// swapoff		// 1095
671	data8 0				// reboot
672	data8 0				// truncate
673	data8 0				// ftruncate
674	data8 0				// fchmod
675	data8 0				// fchown		// 1100
676	data8 0				// getpriority
677	data8 0				// setpriority
678	data8 0				// statfs
679	data8 0				// fstatfs
680	data8 0				// gettid		// 1105
681	data8 0				// semget
682	data8 0				// semop
683	data8 0				// semctl
684	data8 0				// msgget
685	data8 0				// msgsnd		// 1110
686	data8 0				// msgrcv
687	data8 0				// msgctl
688	data8 0				// shmget
689	data8 0				// shmat
690	data8 0				// shmdt		// 1115
691	data8 0				// shmctl
692	data8 0				// syslog
693	data8 0				// setitimer
694	data8 0				// getitimer
695	data8 0					 		// 1120
696	data8 0
697	data8 0
698	data8 0				// vhangup
699	data8 0				// lchown
700	data8 0				// remap_file_pages	// 1125
701	data8 0				// wait4
702	data8 0				// sysinfo
703	data8 0				// clone
704	data8 0				// setdomainname
705	data8 0				// newuname		// 1130
706	data8 0				// adjtimex
707	data8 0
708	data8 0				// init_module
709	data8 0				// delete_module
710	data8 0							// 1135
711	data8 0
712	data8 0				// quotactl
713	data8 0				// bdflush
714	data8 0				// sysfs
715	data8 0				// personality		// 1140
716	data8 0				// afs_syscall
717	data8 0				// setfsuid
718	data8 0				// setfsgid
719	data8 0				// getdents
720	data8 0				// flock		// 1145
721	data8 0				// readv
722	data8 0				// writev
723	data8 0				// pread64
724	data8 0				// pwrite64
725	data8 0				// sysctl		// 1150
726	data8 0				// mmap
727	data8 0				// munmap
728	data8 0				// mlock
729	data8 0				// mlockall
730	data8 0				// mprotect		// 1155
731	data8 0				// mremap
732	data8 0				// msync
733	data8 0				// munlock
734	data8 0				// munlockall
735	data8 0				// sched_getparam	// 1160
736	data8 0				// sched_setparam
737	data8 0				// sched_getscheduler
738	data8 0				// sched_setscheduler
739	data8 0				// sched_yield
740	data8 0				// sched_get_priority_max	// 1165
741	data8 0				// sched_get_priority_min
742	data8 0				// sched_rr_get_interval
743	data8 0				// nanosleep
744	data8 0				// nfsservctl
745	data8 0				// prctl		// 1170
746	data8 0				// getpagesize
747	data8 0				// mmap2
748	data8 0				// pciconfig_read
749	data8 0				// pciconfig_write
750	data8 0				// perfmonctl		// 1175
751	data8 0				// sigaltstack
752	data8 0				// rt_sigaction
753	data8 0				// rt_sigpending
754	data8 0				// rt_sigprocmask
755	data8 0				// rt_sigqueueinfo	// 1180
756	data8 0				// rt_sigreturn
757	data8 0				// rt_sigsuspend
758	data8 0				// rt_sigtimedwait
759	data8 0				// getcwd
760	data8 0				// capget		// 1185
761	data8 0				// capset
762	data8 0				// sendfile
763	data8 0
764	data8 0
765	data8 0				// socket		// 1190
766	data8 0				// bind
767	data8 0				// connect
768	data8 0				// listen
769	data8 0				// accept
770	data8 0				// getsockname		// 1195
771	data8 0				// getpeername
772	data8 0				// socketpair
773	data8 0				// send
774	data8 0				// sendto
775	data8 0				// recv			// 1200
776	data8 0				// recvfrom
777	data8 0				// shutdown
778	data8 0				// setsockopt
779	data8 0				// getsockopt
780	data8 0				// sendmsg		// 1205
781	data8 0				// recvmsg
782	data8 0				// pivot_root
783	data8 0				// mincore
784	data8 0				// madvise
785	data8 0				// newstat		// 1210
786	data8 0				// newlstat
787	data8 0				// newfstat
788	data8 0				// clone2
789	data8 0				// getdents64
790	data8 0				// getunwind		// 1215
791	data8 0				// readahead
792	data8 0				// setxattr
793	data8 0				// lsetxattr
794	data8 0				// fsetxattr
795	data8 0				// getxattr		// 1220
796	data8 0				// lgetxattr
797	data8 0				// fgetxattr
798	data8 0				// listxattr
799	data8 0				// llistxattr
800	data8 0				// flistxattr		// 1225
801	data8 0				// removexattr
802	data8 0				// lremovexattr
803	data8 0				// fremovexattr
804	data8 0				// tkill
805	data8 0				// futex		// 1230
806	data8 0				// sched_setaffinity
807	data8 0				// sched_getaffinity
808	data8 fsys_set_tid_address	// set_tid_address
809	data8 0				// fadvise64_64
810	data8 0				// tgkill		// 1235
811	data8 0				// exit_group
812	data8 0				// lookup_dcookie
813	data8 0				// io_setup
814	data8 0				// io_destroy
815	data8 0				// io_getevents		// 1240
816	data8 0				// io_submit
817	data8 0				// io_cancel
818	data8 0				// epoll_create
819	data8 0				// epoll_ctl
820	data8 0				// epoll_wait		// 1245
821	data8 0				// restart_syscall
822	data8 0				// semtimedop
823	data8 0				// timer_create
824	data8 0				// timer_settime
825	data8 0				// timer_gettime 	// 1250
826	data8 0				// timer_getoverrun
827	data8 0				// timer_delete
828	data8 0				// clock_settime
829	data8 fsys_clock_gettime	// clock_gettime
830	data8 0				// clock_getres		// 1255
831	data8 0				// clock_nanosleep
832	data8 0				// fstatfs64
833	data8 0				// statfs64
834	data8 0				// mbind
835	data8 0				// get_mempolicy	// 1260
836	data8 0				// set_mempolicy
837	data8 0				// mq_open
838	data8 0				// mq_unlink
839	data8 0				// mq_timedsend
840	data8 0				// mq_timedreceive	// 1265
841	data8 0				// mq_notify
842	data8 0				// mq_getsetattr
843	data8 0				// kexec_load
844	data8 0				// vserver
845	data8 0				// waitid		// 1270
846	data8 0				// add_key
847	data8 0				// request_key
848	data8 0				// keyctl
849	data8 0				// ioprio_set
850	data8 0				// ioprio_get		// 1275
851	data8 0				// move_pages
852	data8 0				// inotify_init
853	data8 0				// inotify_add_watch
854	data8 0				// inotify_rm_watch
855	data8 0				// migrate_pages	// 1280
856	data8 0				// openat
857	data8 0				// mkdirat
858	data8 0				// mknodat
859	data8 0				// fchownat
860	data8 0				// futimesat		// 1285
861	data8 0				// newfstatat
862	data8 0				// unlinkat
863	data8 0				// renameat
864	data8 0				// linkat
865	data8 0				// symlinkat		// 1290
866	data8 0				// readlinkat
867	data8 0				// fchmodat
868	data8 0				// faccessat
869	data8 0
870	data8 0							// 1295
871	data8 0				// unshare
872	data8 0				// splice
873	data8 0				// set_robust_list
874	data8 0				// get_robust_list
875	data8 0				// sync_file_range	// 1300
876	data8 0				// tee
877	data8 0				// vmsplice
878	data8 0
879	data8 fsys_getcpu		// getcpu		// 1304
880
881	// fill in zeros for the remaining entries
882	.zero:
883	.space paravirt_fsyscall_table + 8*NR_syscalls - .zero, 0