xref: /openbmc/linux/arch/parisc/kernel/syscall.S (revision 96de0e252cedffad61b3cb5e05662c591898e69a)
1/*
2 * Linux/PA-RISC Project (http://www.parisc-linux.org/)
3 *
4 * System call entry code Copyright (c) Matthew Wilcox 1999 <willy@bofh.ai>
5 * Licensed under the GNU GPL.
6 * thanks to Philipp Rumpf, Mike Shaver and various others
7 * sorry about the wall, puffin..
8 */
9
10#include <asm/asm-offsets.h>
11#include <asm/unistd.h>
12#include <asm/errno.h>
13#include <asm/psw.h>
14#include <asm/thread_info.h>
15#include <asm/assembly.h>
16#include <asm/processor.h>
17
18#include <linux/linkage.h>
19
20	/* We fill the empty parts of the gateway page with
21 	 * something that will kill the kernel or a
22 	 * userspace application.
23	 */
24#define KILL_INSN	break	0,0
25
26	.level          LEVEL
27
28	.text
29
30	.import syscall_exit,code
31	.import syscall_exit_rfi,code
32
33	/* Linux gateway page is aliased to virtual page 0 in the kernel
34	 * address space. Since it is a gateway page it cannot be
35	 * dereferenced, so null pointers will still fault. We start
36	 * the actual entry point at 0x100. We put break instructions
37	 * at the beginning of the page to trap null indirect function
38	 * pointers.
39	 */
40
41	.align ASM_PAGE_SIZE
42ENTRY(linux_gateway_page)
43
44        /* ADDRESS 0x00 to 0xb0 = 176 bytes / 4 bytes per insn = 44 insns */
45	.rept 44
46	KILL_INSN
47	.endr
48
49	/* ADDRESS 0xb0 to 0xb4, lws uses 1 insns for entry */
50	/* Light-weight-syscall entry must always be located at 0xb0 */
51	/* WARNING: Keep this number updated with table size changes */
52#define __NR_lws_entries (2)
53
54lws_entry:
55	/* Unconditional branch to lws_start, located on the
56	   same gateway page */
57	b,n	lws_start
58
59	/* Fill from 0xb4 to 0xe0 */
60	.rept 11
61	KILL_INSN
62	.endr
63
64	/* This function MUST be located at 0xe0 for glibc's threading
65	mechanism to work. DO NOT MOVE THIS CODE EVER! */
66set_thread_pointer:
67	gate	.+8, %r0		/* increase privilege */
68	depi	3, 31, 2, %r31		/* Ensure we return into user mode. */
69	be	0(%sr7,%r31)		/* return to user space */
70	mtctl	%r26, %cr27		/* move arg0 to the control register */
71
72	/* Increase the chance of trapping if random jumps occur to this
73	address, fill from 0xf0 to 0x100 */
74	.rept 4
75	KILL_INSN
76	.endr
77
78/* This address must remain fixed at 0x100 for glibc's syscalls to work */
79	.align 256
80linux_gateway_entry:
81	gate	.+8, %r0			/* become privileged */
82	mtsp	%r0,%sr4			/* get kernel space into sr4 */
83	mtsp	%r0,%sr5			/* get kernel space into sr5 */
84	mtsp	%r0,%sr6			/* get kernel space into sr6 */
85	mfsp    %sr7,%r1                        /* save user sr7 */
86	mtsp    %r1,%sr3                        /* and store it in sr3 */
87
88#ifdef CONFIG_64BIT
89	/* for now we can *always* set the W bit on entry to the syscall
90	 * since we don't support wide userland processes.  We could
91	 * also save the current SM other than in r0 and restore it on
92	 * exit from the syscall, and also use that value to know
93	 * whether to do narrow or wide syscalls. -PB
94	 */
95	ssm	PSW_SM_W, %r1
96	extrd,u	%r1,PSW_W_BIT,1,%r1
97	/* sp must be aligned on 4, so deposit the W bit setting into
98	 * the bottom of sp temporarily */
99	or,ev	%r1,%r30,%r30
100	b,n	1f
101	/* The top halves of argument registers must be cleared on syscall
102	 * entry from narrow executable.
103	 */
104	depdi	0, 31, 32, %r26
105	depdi	0, 31, 32, %r25
106	depdi	0, 31, 32, %r24
107	depdi	0, 31, 32, %r23
108	depdi	0, 31, 32, %r22
109	depdi	0, 31, 32, %r21
1101:
111#endif
112	mfctl   %cr30,%r1
113	xor     %r1,%r30,%r30                   /* ye olde xor trick */
114	xor     %r1,%r30,%r1
115	xor     %r1,%r30,%r30
116
117	ldo     THREAD_SZ_ALGN+FRAME_SIZE(%r30),%r30  /* set up kernel stack */
118
119	/* N.B.: It is critical that we don't set sr7 to 0 until r30
120	 *       contains a valid kernel stack pointer. It is also
121	 *       critical that we don't start using the kernel stack
122	 *       until after sr7 has been set to 0.
123	 */
124
125	mtsp	%r0,%sr7			/* get kernel space into sr7 */
126	STREGM	%r1,FRAME_SIZE(%r30)		/* save r1 (usp) here for now */
127	mfctl	%cr30,%r1			/* get task ptr in %r1 */
128	LDREG	TI_TASK(%r1),%r1
129
130	/* Save some registers for sigcontext and potential task
131	   switch (see entry.S for the details of which ones are
132	   saved/restored).  TASK_PT_PSW is zeroed so we can see whether
133	   a process is on a syscall or not.  For an interrupt the real
134	   PSW value is stored.  This is needed for gdb and sys_ptrace. */
135	STREG	%r0,  TASK_PT_PSW(%r1)
136	STREG	%r2,  TASK_PT_GR2(%r1)		/* preserve rp */
137	STREG	%r19, TASK_PT_GR19(%r1)
138
139	LDREGM	-FRAME_SIZE(%r30), %r2		/* get users sp back */
140#ifdef CONFIG_64BIT
141	extrd,u	%r2,63,1,%r19			/* W hidden in bottom bit */
142#if 0
143	xor	%r19,%r2,%r2			/* clear bottom bit */
144	depd,z	%r19,1,1,%r19
145	std	%r19,TASK_PT_PSW(%r1)
146#endif
147#endif
148	STREG	%r2,  TASK_PT_GR30(%r1)		/* ... and save it */
149
150	STREG	%r20, TASK_PT_GR20(%r1)		/* Syscall number */
151	STREG	%r21, TASK_PT_GR21(%r1)
152	STREG	%r22, TASK_PT_GR22(%r1)
153	STREG	%r23, TASK_PT_GR23(%r1)		/* 4th argument */
154	STREG	%r24, TASK_PT_GR24(%r1)		/* 3rd argument */
155	STREG	%r25, TASK_PT_GR25(%r1)		/* 2nd argument */
156	STREG	%r26, TASK_PT_GR26(%r1)	 	/* 1st argument */
157	STREG	%r27, TASK_PT_GR27(%r1)		/* user dp */
158	STREG   %r28, TASK_PT_GR28(%r1)         /* return value 0 */
159	STREG   %r28, TASK_PT_ORIG_R28(%r1)     /* return value 0 (saved for signals) */
160	STREG	%r29, TASK_PT_GR29(%r1)		/* return value 1 */
161	STREG	%r31, TASK_PT_GR31(%r1)		/* preserve syscall return ptr */
162
163	ldo	TASK_PT_FR0(%r1), %r27		/* save fpregs from the kernel */
164	save_fp	%r27				/* or potential task switch  */
165
166	mfctl	%cr11, %r27			/* i.e. SAR */
167	STREG	%r27, TASK_PT_SAR(%r1)
168
169	loadgp
170
171#ifdef CONFIG_64BIT
172	ldo	-16(%r30),%r29			/* Reference param save area */
173	copy	%r19,%r2			/* W bit back to r2 */
174#else
175	/* no need to save these on stack in wide mode because the first 8
176	 * args are passed in registers */
177	stw     %r22, -52(%r30)                 /* 5th argument */
178	stw     %r21, -56(%r30)                 /* 6th argument */
179#endif
180
181	/* Are we being ptraced? */
182	mfctl	%cr30, %r1
183	LDREG	TI_TASK(%r1),%r1
184	ldw	TASK_PTRACE(%r1), %r1
185	bb,<,n	%r1,31,.Ltracesys
186
187	/* Note!  We cannot use the syscall table that is mapped
188	nearby since the gateway page is mapped execute-only. */
189
190#ifdef CONFIG_64BIT
191	ldil	L%sys_call_table, %r1
192	or,=	%r2,%r2,%r2
193	addil	L%(sys_call_table64-sys_call_table), %r1
194	ldo	R%sys_call_table(%r1), %r19
195	or,=	%r2,%r2,%r2
196	ldo	R%sys_call_table64(%r1), %r19
197#else
198	ldil	L%sys_call_table, %r1
199	ldo     R%sys_call_table(%r1), %r19
200#endif
201	comiclr,>>	__NR_Linux_syscalls, %r20, %r0
202	b,n	.Lsyscall_nosys
203
204	LDREGX  %r20(%r19), %r19
205
206	/* If this is a sys_rt_sigreturn call, and the signal was received
207	 * when not in_syscall, then we want to return via syscall_exit_rfi,
208	 * not syscall_exit.  Signal no. in r20, in_syscall in r25 (see
209	 * trampoline code in signal.c).
210	 */
211	ldi	__NR_rt_sigreturn,%r2
212	comb,=	%r2,%r20,.Lrt_sigreturn
213.Lin_syscall:
214	ldil	L%syscall_exit,%r2
215	be      0(%sr7,%r19)
216	ldo	R%syscall_exit(%r2),%r2
217.Lrt_sigreturn:
218	comib,<> 0,%r25,.Lin_syscall
219	ldil	L%syscall_exit_rfi,%r2
220	be      0(%sr7,%r19)
221	ldo	R%syscall_exit_rfi(%r2),%r2
222
223	/* Note!  Because we are not running where we were linked, any
224	calls to functions external to this file must be indirect.  To
225	be safe, we apply the opposite rule to functions within this
226	file, with local labels given to them to ensure correctness. */
227
228.Lsyscall_nosys:
229syscall_nosys:
230	ldil	L%syscall_exit,%r1
231	be	R%syscall_exit(%sr7,%r1)
232	ldo	-ENOSYS(%r0),%r28		   /* set errno */
233
234
235/* Warning! This trace code is a virtual duplicate of the code above so be
236 * sure to maintain both! */
237.Ltracesys:
238tracesys:
239	/* Need to save more registers so the debugger can see where we
240	 * are.  This saves only the lower 8 bits of PSW, so that the C
241	 * bit is still clear on syscalls, and the D bit is set if this
242	 * full register save path has been executed.  We check the D
243	 * bit on syscall_return_rfi to determine which registers to
244	 * restore.  An interrupt results in a full PSW saved with the
245	 * C bit set, a non-straced syscall entry results in C and D clear
246	 * in the saved PSW.
247	 */
248	ldo     -THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1      /* get task ptr */
249	LDREG	TI_TASK(%r1), %r1
250	ssm	0,%r2
251	STREG	%r2,TASK_PT_PSW(%r1)		/* Lower 8 bits only!! */
252	mfsp	%sr0,%r2
253	STREG	%r2,TASK_PT_SR0(%r1)
254	mfsp	%sr1,%r2
255	STREG	%r2,TASK_PT_SR1(%r1)
256	mfsp	%sr2,%r2
257	STREG	%r2,TASK_PT_SR2(%r1)
258	mfsp	%sr3,%r2
259	STREG	%r2,TASK_PT_SR3(%r1)
260	STREG	%r2,TASK_PT_SR4(%r1)
261	STREG	%r2,TASK_PT_SR5(%r1)
262	STREG	%r2,TASK_PT_SR6(%r1)
263	STREG	%r2,TASK_PT_SR7(%r1)
264	STREG	%r2,TASK_PT_IASQ0(%r1)
265	STREG	%r2,TASK_PT_IASQ1(%r1)
266	LDREG	TASK_PT_GR31(%r1),%r2
267	STREG	%r2,TASK_PT_IAOQ0(%r1)
268	ldo	4(%r2),%r2
269	STREG	%r2,TASK_PT_IAOQ1(%r1)
270	ldo	TASK_REGS(%r1),%r2
271	/* reg_save %r2 */
272	STREG	%r3,PT_GR3(%r2)
273	STREG	%r4,PT_GR4(%r2)
274	STREG	%r5,PT_GR5(%r2)
275	STREG	%r6,PT_GR6(%r2)
276	STREG	%r7,PT_GR7(%r2)
277	STREG	%r8,PT_GR8(%r2)
278	STREG	%r9,PT_GR9(%r2)
279	STREG	%r10,PT_GR10(%r2)
280	STREG	%r11,PT_GR11(%r2)
281	STREG	%r12,PT_GR12(%r2)
282	STREG	%r13,PT_GR13(%r2)
283	STREG	%r14,PT_GR14(%r2)
284	STREG	%r15,PT_GR15(%r2)
285	STREG	%r16,PT_GR16(%r2)
286	STREG	%r17,PT_GR17(%r2)
287	STREG	%r18,PT_GR18(%r2)
288	/* Finished saving things for the debugger */
289
290	ldil	L%syscall_trace,%r1
291	ldil	L%tracesys_next,%r2
292	be	R%syscall_trace(%sr7,%r1)
293	ldo	R%tracesys_next(%r2),%r2
294
295tracesys_next:
296	ldil	L%sys_call_table,%r1
297	ldo     R%sys_call_table(%r1), %r19
298
299	ldo     -THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1      /* get task ptr */
300	LDREG	TI_TASK(%r1), %r1
301	LDREG   TASK_PT_GR20(%r1), %r20
302	LDREG   TASK_PT_GR26(%r1), %r26		/* Restore the users args */
303	LDREG   TASK_PT_GR25(%r1), %r25
304	LDREG   TASK_PT_GR24(%r1), %r24
305	LDREG   TASK_PT_GR23(%r1), %r23
306#ifdef CONFIG_64BIT
307	LDREG   TASK_PT_GR22(%r1), %r22
308	LDREG   TASK_PT_GR21(%r1), %r21
309	ldo	-16(%r30),%r29			/* Reference param save area */
310#endif
311
312	comiclr,>>=	__NR_Linux_syscalls, %r20, %r0
313	b,n	.Lsyscall_nosys
314
315	LDREGX  %r20(%r19), %r19
316
317	/* If this is a sys_rt_sigreturn call, and the signal was received
318	 * when not in_syscall, then we want to return via syscall_exit_rfi,
319	 * not syscall_exit.  Signal no. in r20, in_syscall in r25 (see
320	 * trampoline code in signal.c).
321	 */
322	ldi	__NR_rt_sigreturn,%r2
323	comb,=	%r2,%r20,.Ltrace_rt_sigreturn
324.Ltrace_in_syscall:
325	ldil	L%tracesys_exit,%r2
326	be      0(%sr7,%r19)
327	ldo	R%tracesys_exit(%r2),%r2
328
329	/* Do *not* call this function on the gateway page, because it
330	makes a direct call to syscall_trace. */
331
332tracesys_exit:
333	ldo     -THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1      /* get task ptr */
334	LDREG	TI_TASK(%r1), %r1
335#ifdef CONFIG_64BIT
336	ldo	-16(%r30),%r29			/* Reference param save area */
337#endif
338	bl	syscall_trace, %r2
339	STREG   %r28,TASK_PT_GR28(%r1)          /* save return value now */
340	ldo     -THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1      /* get task ptr */
341	LDREG	TI_TASK(%r1), %r1
342	LDREG   TASK_PT_GR28(%r1), %r28		/* Restore return val. */
343
344	ldil	L%syscall_exit,%r1
345	be,n	R%syscall_exit(%sr7,%r1)
346
347.Ltrace_rt_sigreturn:
348	comib,<> 0,%r25,.Ltrace_in_syscall
349	ldil	L%tracesys_sigexit,%r2
350	be      0(%sr7,%r19)
351	ldo	R%tracesys_sigexit(%r2),%r2
352
353tracesys_sigexit:
354	ldo     -THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1      /* get task ptr */
355	LDREG	0(%r1), %r1
356#ifdef CONFIG_64BIT
357	ldo	-16(%r30),%r29			/* Reference param save area */
358#endif
359	bl	syscall_trace, %r2
360	nop
361
362	ldil	L%syscall_exit_rfi,%r1
363	be,n	R%syscall_exit_rfi(%sr7,%r1)
364
365
366	/*********************************************************
367		Light-weight-syscall code
368
369		r20 - lws number
370		r26,r25,r24,r23,r22 - Input registers
371		r28 - Function return register
372		r21 - Error code.
373
374		Scracth: Any of the above that aren't being
375		currently used, including r1.
376
377		Return pointer: r31 (Not usable)
378
379		Error codes returned by entry path:
380
381		ENOSYS - r20 was an invalid LWS number.
382
383	*********************************************************/
384lws_start:
385	/* Gate and ensure we return to userspace */
386	gate	.+8, %r0
387	depi	3, 31, 2, %r31	/* Ensure we return to userspace */
388
389#ifdef CONFIG_64BIT
390	/* FIXME: If we are a 64-bit kernel just
391	 *        turn this on unconditionally.
392	 */
393	ssm	PSW_SM_W, %r1
394	extrd,u	%r1,PSW_W_BIT,1,%r1
395	/* sp must be aligned on 4, so deposit the W bit setting into
396	 * the bottom of sp temporarily */
397	or,ev	%r1,%r30,%r30
398
399	/* Clip LWS number to a 32-bit value always */
400	depdi	0, 31, 32, %r20
401#endif
402
403        /* Is the lws entry number valid? */
404	comiclr,>>=	__NR_lws_entries, %r20, %r0
405	b,n	lws_exit_nosys
406
407	/* WARNING: Trashing sr2 and sr3 */
408	mfsp	%sr7,%r1			/* get userspace into sr3 */
409	mtsp	%r1,%sr3
410	mtsp	%r0,%sr2			/* get kernel space into sr2 */
411
412	/* Load table start */
413	ldil	L%lws_table, %r1
414	ldo	R%lws_table(%r1), %r28	/* Scratch use of r28 */
415	LDREGX	%r20(%sr2,r28), %r21	/* Scratch use of r21 */
416
417	/* Jump to lws, lws table pointers already relocated */
418	be,n	0(%sr2,%r21)
419
420lws_exit_nosys:
421	ldo	-ENOSYS(%r0),%r21		   /* set errno */
422	/* Fall through: Return to userspace */
423
424lws_exit:
425#ifdef CONFIG_64BIT
426	/* decide whether to reset the wide mode bit
427	 *
428	 * For a syscall, the W bit is stored in the lowest bit
429	 * of sp.  Extract it and reset W if it is zero */
430	extrd,u,*<>	%r30,63,1,%r1
431	rsm	PSW_SM_W, %r0
432	/* now reset the lowest bit of sp if it was set */
433	xor	%r30,%r1,%r30
434#endif
435	be,n	0(%sr3, %r31)
436
437
438
439	/***************************************************
440		Implementing CAS as an atomic operation:
441
442		%r26 - Address to examine
443		%r25 - Old value to check (old)
444		%r24 - New value to set (new)
445		%r28 - Return prev through this register.
446		%r21 - Kernel error code
447
448		If debugging is DISabled:
449
450		%r21 has the following meanings:
451
452		EAGAIN - CAS is busy, ldcw failed, try again.
453		EFAULT - Read or write failed.
454
455		If debugging is enabled:
456
457		EDEADLOCK - CAS called recursively.
458		EAGAIN && r28 == 1 - CAS is busy. Lock contended.
459		EAGAIN && r28 == 2 - CAS is busy. ldcw failed.
460		EFAULT - Read or write failed.
461
462		Scratch: r20, r28, r1
463
464	****************************************************/
465
466	/* Do not enable LWS debugging */
467#define ENABLE_LWS_DEBUG 0
468
469	/* ELF64 Process entry path */
470lws_compare_and_swap64:
471#ifdef CONFIG_64BIT
472	b,n	lws_compare_and_swap
473#else
474	/* If we are not a 64-bit kernel, then we don't
475	 * implement having 64-bit input registers
476	 */
477	b,n	lws_exit_nosys
478#endif
479
480	/* ELF32 Process entry path */
481lws_compare_and_swap32:
482#ifdef CONFIG_64BIT
483	/* Clip all the input registers */
484	depdi	0, 31, 32, %r26
485	depdi	0, 31, 32, %r25
486	depdi	0, 31, 32, %r24
487#endif
488
489lws_compare_and_swap:
490#ifdef CONFIG_SMP
491	/* Load start of lock table */
492	ldil	L%lws_lock_start, %r20
493	ldo	R%lws_lock_start(%r20), %r28
494
495	/* Extract four bits from r26 and hash lock (Bits 4-7) */
496	extru  %r26, 27, 4, %r20
497
498	/* Find lock to use, the hash is either one of 0 to
499	   15, multiplied by 16 (keep it 16-byte aligned)
500	   and add to the lock table offset. */
501	shlw	%r20, 4, %r20
502	add	%r20, %r28, %r20
503
504# if ENABLE_LWS_DEBUG
505	/*
506		DEBUG, check for deadlock!
507		If the thread register values are the same
508		then we were the one that locked it last and
509		this is a recurisve call that will deadlock.
510		We *must* giveup this call and fail.
511	*/
512	ldw	4(%sr2,%r20), %r28			/* Load thread register */
513	/* WARNING: If cr27 cycles to the same value we have problems */
514	mfctl	%cr27, %r21				/* Get current thread register */
515	cmpb,<>,n	%r21, %r28, cas_lock		/* Called recursive? */
516	b	lws_exit				/* Return error! */
517	ldo	-EDEADLOCK(%r0), %r21
518cas_lock:
519	cmpb,=,n	%r0, %r28, cas_nocontend	/* Is nobody using it? */
520	ldo	1(%r0), %r28				/* 1st case */
521	b	lws_exit				/* Contended... */
522	ldo	-EAGAIN(%r0), %r21			/* Spin in userspace */
523cas_nocontend:
524# endif
525/* ENABLE_LWS_DEBUG */
526
527	LDCW	0(%sr2,%r20), %r28			/* Try to acquire the lock */
528	cmpb,<>,n	%r0, %r28, cas_action		/* Did we get it? */
529cas_wouldblock:
530	ldo	2(%r0), %r28				/* 2nd case */
531	b	lws_exit				/* Contended... */
532	ldo	-EAGAIN(%r0), %r21			/* Spin in userspace */
533#endif
534/* CONFIG_SMP */
535
536	/*
537		prev = *addr;
538		if ( prev == old )
539		  *addr = new;
540		return prev;
541	*/
542
543	/* NOTES:
544		This all works becuse intr_do_signal
545		and schedule both check the return iasq
546		and see that we are on the kernel page
547		so this process is never scheduled off
548		or is ever sent any signal of any sort,
549		thus it is wholly atomic from usrspaces
550		perspective
551	*/
552cas_action:
553#if defined CONFIG_SMP && ENABLE_LWS_DEBUG
554	/* DEBUG */
555	mfctl	%cr27, %r1
556	stw	%r1, 4(%sr2,%r20)
557#endif
558	/* The load and store could fail */
5591:	ldw	0(%sr3,%r26), %r28
560	sub,<>	%r28, %r25, %r0
5612:	stw	%r24, 0(%sr3,%r26)
562#ifdef CONFIG_SMP
563	/* Free lock */
564	stw	%r20, 0(%sr2,%r20)
565# if ENABLE_LWS_DEBUG
566	/* Clear thread register indicator */
567	stw	%r0, 4(%sr2,%r20)
568# endif
569#endif
570	/* Return to userspace, set no error */
571	b	lws_exit
572	copy	%r0, %r21
573
5743:
575	/* Error occured on load or store */
576#ifdef CONFIG_SMP
577	/* Free lock */
578	stw	%r20, 0(%sr2,%r20)
579# if ENABLE_LWS_DEBUG
580	stw	%r0, 4(%sr2,%r20)
581# endif
582#endif
583	b	lws_exit
584	ldo	-EFAULT(%r0),%r21	/* set errno */
585	nop
586	nop
587	nop
588	nop
589
590	/* Two exception table entries, one for the load,
591	   the other for the store. Either return -EFAULT.
592	   Each of the entries must be relocated. */
593	.section __ex_table,"aw"
594	ASM_ULONG_INSN (1b - linux_gateway_page), (3b - linux_gateway_page)
595	ASM_ULONG_INSN (2b - linux_gateway_page), (3b - linux_gateway_page)
596	.previous
597
598
599	/* Make sure nothing else is placed on this page */
600	.align ASM_PAGE_SIZE
601END(linux_gateway_page)
602ENTRY(end_linux_gateway_page)
603
604	/* Relocate symbols assuming linux_gateway_page is mapped
605	   to virtual address 0x0 */
606
607#define LWS_ENTRY(_name_) ASM_ULONG_INSN (lws_##_name_ - linux_gateway_page)
608
609	.section .rodata,"a"
610
611	.align ASM_PAGE_SIZE
612	/* Light-weight-syscall table */
613	/* Start of lws table. */
614ENTRY(lws_table)
615	LWS_ENTRY(compare_and_swap32)	/* 0 - ELF32 Atomic compare and swap */
616	LWS_ENTRY(compare_and_swap64)	/* 1 - ELF64 Atomic compare and swap */
617END(lws_table)
618	/* End of lws table */
619
620	.align ASM_PAGE_SIZE
621ENTRY(sys_call_table)
622#include "syscall_table.S"
623END(sys_call_table)
624
625#ifdef CONFIG_64BIT
626	.align ASM_PAGE_SIZE
627ENTRY(sys_call_table64)
628#define SYSCALL_TABLE_64BIT
629#include "syscall_table.S"
630END(sys_call_table64)
631#endif
632
633#ifdef CONFIG_SMP
634	/*
635		All light-weight-syscall atomic operations
636		will use this set of locks
637	*/
638	.section .data
639	.align 4096
640ENTRY(lws_lock_start)
641	/* lws locks */
642	.align 16
643	.rept 16
644	/* Keep locks aligned at 16-bytes */
645	.word 1
646	.word 0
647	.word 0
648	.word 0
649	.endr
650END(lws_lock_start)
651	.previous
652#endif
653/* CONFIG_SMP for lws_lock_start */
654
655.end
656
657
658