| blob | 59fc1a43ec3ef094ae514694e549ab6b518aa05a |
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 */
10 #include <asm/asm-offsets.h>
11 #include <asm/unistd.h>
12 #include <asm/errno.h>
13 #include <asm/page.h>
14 #include <asm/psw.h>
15 #include <asm/thread_info.h>
16 #include <asm/assembly.h>
17 #include <asm/processor.h>
19 #include <linux/linkage.h>
21 /* We fill the empty parts of the gateway page with
22 * something that will kill the kernel or a
23 * userspace application.
24 */
25 #define KILL_INSN break 0,0
27 .level LEVEL
29 .text
31 .import syscall_exit,code
32 .import syscall_exit_rfi,code
34 /* Linux gateway page is aliased to virtual page 0 in the kernel
35 * address space. Since it is a gateway page it cannot be
36 * dereferenced, so null pointers will still fault. We start
37 * the actual entry point at 0x100. We put break instructions
38 * at the beginning of the page to trap null indirect function
39 * pointers.
40 */
42 .align PAGE_SIZE
43 ENTRY(linux_gateway_page)
45 /* ADDRESS 0x00 to 0xb0 = 176 bytes / 4 bytes per insn = 44 insns */
46 .rept 44
47 KILL_INSN
48 .endr
50 /* ADDRESS 0xb0 to 0xb4, lws uses 1 insns for entry */
51 /* Light-weight-syscall entry must always be located at 0xb0 */
52 /* WARNING: Keep this number updated with table size changes */
53 #define __NR_lws_entries (2)
55 lws_entry:
56 /* Unconditional branch to lws_start, located on the
57 same gateway page */
58 b,n lws_start
60 /* Fill from 0xb4 to 0xe0 */
61 .rept 11
62 KILL_INSN
63 .endr
65 /* This function MUST be located at 0xe0 for glibc's threading
66 mechanism to work. DO NOT MOVE THIS CODE EVER! */
67 set_thread_pointer:
68 gate .+8, %r0 /* increase privilege */
69 depi 3, 31, 2, %r31 /* Ensure we return into user mode. */
70 be 0(%sr7,%r31) /* return to user space */
71 mtctl %r26, %cr27 /* move arg0 to the control register */
73 /* Increase the chance of trapping if random jumps occur to this
74 address, fill from 0xf0 to 0x100 */
75 .rept 4
76 KILL_INSN
77 .endr
79 /* This address must remain fixed at 0x100 for glibc's syscalls to work */
80 .align 256
81 linux_gateway_entry:
82 gate .+8, %r0 /* become privileged */
83 mtsp %r0,%sr4 /* get kernel space into sr4 */
84 mtsp %r0,%sr5 /* get kernel space into sr5 */
85 mtsp %r0,%sr6 /* get kernel space into sr6 */
86 mfsp %sr7,%r1 /* save user sr7 */
87 mtsp %r1,%sr3 /* and store it in sr3 */
89 #ifdef CONFIG_64BIT
90 /* for now we can *always* set the W bit on entry to the syscall
91 * since we don't support wide userland processes. We could
92 * also save the current SM other than in r0 and restore it on
93 * exit from the syscall, and also use that value to know
94 * whether to do narrow or wide syscalls. -PB
95 */
96 ssm PSW_SM_W, %r1
97 extrd,u %r1,PSW_W_BIT,1,%r1
98 /* sp must be aligned on 4, so deposit the W bit setting into
99 * the bottom of sp temporarily */
100 or,ev %r1,%r30,%r30
101 b,n 1f
102 /* The top halves of argument registers must be cleared on syscall
103 * entry from narrow executable.
104 */
105 depdi 0, 31, 32, %r26
106 depdi 0, 31, 32, %r25
107 depdi 0, 31, 32, %r24
108 depdi 0, 31, 32, %r23
109 depdi 0, 31, 32, %r22
110 depdi 0, 31, 32, %r21
111 1:
112 #endif
113 mfctl %cr30,%r1
114 xor %r1,%r30,%r30 /* ye olde xor trick */
115 xor %r1,%r30,%r1
116 xor %r1,%r30,%r30
118 ldo THREAD_SZ_ALGN+FRAME_SIZE(%r30),%r30 /* set up kernel stack */
120 /* N.B.: It is critical that we don't set sr7 to 0 until r30
121 * contains a valid kernel stack pointer. It is also
122 * critical that we don't start using the kernel stack
123 * until after sr7 has been set to 0.
124 */
126 mtsp %r0,%sr7 /* get kernel space into sr7 */
127 STREGM %r1,FRAME_SIZE(%r30) /* save r1 (usp) here for now */
128 mfctl %cr30,%r1 /* get task ptr in %r1 */
129 LDREG TI_TASK(%r1),%r1
131 /* Save some registers for sigcontext and potential task
132 switch (see entry.S for the details of which ones are
133 saved/restored). TASK_PT_PSW is zeroed so we can see whether
134 a process is on a syscall or not. For an interrupt the real
135 PSW value is stored. This is needed for gdb and sys_ptrace. */
136 STREG %r0, TASK_PT_PSW(%r1)
137 STREG %r2, TASK_PT_GR2(%r1) /* preserve rp */
138 STREG %r19, TASK_PT_GR19(%r1)
140 LDREGM -FRAME_SIZE(%r30), %r2 /* get users sp back */
141 #ifdef CONFIG_64BIT
142 extrd,u %r2,63,1,%r19 /* W hidden in bottom bit */
143 #if 0
144 xor %r19,%r2,%r2 /* clear bottom bit */
145 depd,z %r19,1,1,%r19
146 std %r19,TASK_PT_PSW(%r1)
147 #endif
148 #endif
149 STREG %r2, TASK_PT_GR30(%r1) /* ... and save it */
151 STREG %r20, TASK_PT_GR20(%r1) /* Syscall number */
152 STREG %r21, TASK_PT_GR21(%r1)
153 STREG %r22, TASK_PT_GR22(%r1)
154 STREG %r23, TASK_PT_GR23(%r1) /* 4th argument */
155 STREG %r24, TASK_PT_GR24(%r1) /* 3rd argument */
156 STREG %r25, TASK_PT_GR25(%r1) /* 2nd argument */
157 STREG %r26, TASK_PT_GR26(%r1) /* 1st argument */
158 STREG %r27, TASK_PT_GR27(%r1) /* user dp */
159 STREG %r28, TASK_PT_GR28(%r1) /* return value 0 */
160 STREG %r28, TASK_PT_ORIG_R28(%r1) /* return value 0 (saved for signals) */
161 STREG %r29, TASK_PT_GR29(%r1) /* return value 1 */
162 STREG %r31, TASK_PT_GR31(%r1) /* preserve syscall return ptr */
164 ldo TASK_PT_FR0(%r1), %r27 /* save fpregs from the kernel */
165 save_fp %r27 /* or potential task switch */
167 mfctl %cr11, %r27 /* i.e. SAR */
168 STREG %r27, TASK_PT_SAR(%r1)
170 loadgp
172 #ifdef CONFIG_64BIT
173 ldo -16(%r30),%r29 /* Reference param save area */
174 copy %r19,%r2 /* W bit back to r2 */
175 #else
176 /* no need to save these on stack in wide mode because the first 8
177 * args are passed in registers */
178 stw %r22, -52(%r30) /* 5th argument */
179 stw %r21, -56(%r30) /* 6th argument */
180 #endif
182 /* Are we being ptraced? */
183 mfctl %cr30, %r1
184 LDREG TI_TASK(%r1),%r1
185 ldw TASK_PTRACE(%r1), %r1
186 bb,<,n %r1,31,.Ltracesys
188 /* Note! We cannot use the syscall table that is mapped
189 nearby since the gateway page is mapped execute-only. */
191 #ifdef CONFIG_64BIT
192 ldil L%sys_call_table, %r1
193 or,= %r2,%r2,%r2
194 addil L%(sys_call_table64-sys_call_table), %r1
195 ldo R%sys_call_table(%r1), %r19
196 or,= %r2,%r2,%r2
197 ldo R%sys_call_table64(%r1), %r19
198 #else
199 ldil L%sys_call_table, %r1
200 ldo R%sys_call_table(%r1), %r19
201 #endif
202 comiclr,>> __NR_Linux_syscalls, %r20, %r0
203 b,n .Lsyscall_nosys
205 LDREGX %r20(%r19), %r19
207 /* If this is a sys_rt_sigreturn call, and the signal was received
208 * when not in_syscall, then we want to return via syscall_exit_rfi,
209 * not syscall_exit. Signal no. in r20, in_syscall in r25 (see
210 * trampoline code in signal.c).
211 */
212 ldi __NR_rt_sigreturn,%r2
213 comb,= %r2,%r20,.Lrt_sigreturn
214 .Lin_syscall:
215 ldil L%syscall_exit,%r2
216 be 0(%sr7,%r19)
217 ldo R%syscall_exit(%r2),%r2
218 .Lrt_sigreturn:
219 comib,<> 0,%r25,.Lin_syscall
220 ldil L%syscall_exit_rfi,%r2
221 be 0(%sr7,%r19)
222 ldo R%syscall_exit_rfi(%r2),%r2
224 /* Note! Because we are not running where we were linked, any
225 calls to functions external to this file must be indirect. To
226 be safe, we apply the opposite rule to functions within this
227 file, with local labels given to them to ensure correctness. */
229 .Lsyscall_nosys:
230 syscall_nosys:
231 ldil L%syscall_exit,%r1
232 be R%syscall_exit(%sr7,%r1)
233 ldo -ENOSYS(%r0),%r28 /* set errno */
236 /* Warning! This trace code is a virtual duplicate of the code above so be
237 * sure to maintain both! */
238 .Ltracesys:
239 tracesys:
240 /* Need to save more registers so the debugger can see where we
241 * are. This saves only the lower 8 bits of PSW, so that the C
242 * bit is still clear on syscalls, and the D bit is set if this
243 * full register save path has been executed. We check the D
244 * bit on syscall_return_rfi to determine which registers to
245 * restore. An interrupt results in a full PSW saved with the
246 * C bit set, a non-straced syscall entry results in C and D clear
247 * in the saved PSW.
248 */
249 ldo -THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 /* get task ptr */
250 LDREG TI_TASK(%r1), %r1
251 ssm 0,%r2
252 STREG %r2,TASK_PT_PSW(%r1) /* Lower 8 bits only!! */
253 mfsp %sr0,%r2
254 STREG %r2,TASK_PT_SR0(%r1)
255 mfsp %sr1,%r2
256 STREG %r2,TASK_PT_SR1(%r1)
257 mfsp %sr2,%r2
258 STREG %r2,TASK_PT_SR2(%r1)
259 mfsp %sr3,%r2
260 STREG %r2,TASK_PT_SR3(%r1)
261 STREG %r2,TASK_PT_SR4(%r1)
262 STREG %r2,TASK_PT_SR5(%r1)
263 STREG %r2,TASK_PT_SR6(%r1)
264 STREG %r2,TASK_PT_SR7(%r1)
265 STREG %r2,TASK_PT_IASQ0(%r1)
266 STREG %r2,TASK_PT_IASQ1(%r1)
267 LDREG TASK_PT_GR31(%r1),%r2
268 STREG %r2,TASK_PT_IAOQ0(%r1)
269 ldo 4(%r2),%r2
270 STREG %r2,TASK_PT_IAOQ1(%r1)
271 ldo TASK_REGS(%r1),%r2
272 /* reg_save %r2 */
273 STREG %r3,PT_GR3(%r2)
274 STREG %r4,PT_GR4(%r2)
275 STREG %r5,PT_GR5(%r2)
276 STREG %r6,PT_GR6(%r2)
277 STREG %r7,PT_GR7(%r2)
278 STREG %r8,PT_GR8(%r2)
279 STREG %r9,PT_GR9(%r2)
280 STREG %r10,PT_GR10(%r2)
281 STREG %r11,PT_GR11(%r2)
282 STREG %r12,PT_GR12(%r2)
283 STREG %r13,PT_GR13(%r2)
284 STREG %r14,PT_GR14(%r2)
285 STREG %r15,PT_GR15(%r2)
286 STREG %r16,PT_GR16(%r2)
287 STREG %r17,PT_GR17(%r2)
288 STREG %r18,PT_GR18(%r2)
289 /* Finished saving things for the debugger */
291 ldil L%syscall_trace,%r1
292 ldil L%tracesys_next,%r2
293 be R%syscall_trace(%sr7,%r1)
294 ldo R%tracesys_next(%r2),%r2
296 tracesys_next:
297 ldil L%sys_call_table,%r1
298 ldo R%sys_call_table(%r1), %r19
300 ldo -THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 /* get task ptr */
301 LDREG TI_TASK(%r1), %r1
302 LDREG TASK_PT_GR20(%r1), %r20
303 LDREG TASK_PT_GR26(%r1), %r26 /* Restore the users args */
304 LDREG TASK_PT_GR25(%r1), %r25
305 LDREG TASK_PT_GR24(%r1), %r24
306 LDREG TASK_PT_GR23(%r1), %r23
307 #ifdef CONFIG_64BIT
308 LDREG TASK_PT_GR22(%r1), %r22
309 LDREG TASK_PT_GR21(%r1), %r21
310 ldo -16(%r30),%r29 /* Reference param save area */
311 #endif
313 comiclr,>>= __NR_Linux_syscalls, %r20, %r0
314 b,n .Lsyscall_nosys
316 LDREGX %r20(%r19), %r19
318 /* If this is a sys_rt_sigreturn call, and the signal was received
319 * when not in_syscall, then we want to return via syscall_exit_rfi,
320 * not syscall_exit. Signal no. in r20, in_syscall in r25 (see
321 * trampoline code in signal.c).
322 */
323 ldi __NR_rt_sigreturn,%r2
324 comb,= %r2,%r20,.Ltrace_rt_sigreturn
325 .Ltrace_in_syscall:
326 ldil L%tracesys_exit,%r2
327 be 0(%sr7,%r19)
328 ldo R%tracesys_exit(%r2),%r2
330 /* Do *not* call this function on the gateway page, because it
331 makes a direct call to syscall_trace. */
333 tracesys_exit:
334 ldo -THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 /* get task ptr */
335 LDREG TI_TASK(%r1), %r1
336 #ifdef CONFIG_64BIT
337 ldo -16(%r30),%r29 /* Reference param save area */
338 #endif
339 bl syscall_trace, %r2
340 STREG %r28,TASK_PT_GR28(%r1) /* save return value now */
341 ldo -THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 /* get task ptr */
342 LDREG TI_TASK(%r1), %r1
343 LDREG TASK_PT_GR28(%r1), %r28 /* Restore return val. */
345 ldil L%syscall_exit,%r1
346 be,n R%syscall_exit(%sr7,%r1)
348 .Ltrace_rt_sigreturn:
349 comib,<> 0,%r25,.Ltrace_in_syscall
350 ldil L%tracesys_sigexit,%r2
351 be 0(%sr7,%r19)
352 ldo R%tracesys_sigexit(%r2),%r2
354 tracesys_sigexit:
355 ldo -THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 /* get task ptr */
356 LDREG 0(%r1), %r1
357 #ifdef CONFIG_64BIT
358 ldo -16(%r30),%r29 /* Reference param save area */
359 #endif
360 bl syscall_trace, %r2
361 nop
363 ldil L%syscall_exit_rfi,%r1
364 be,n R%syscall_exit_rfi(%sr7,%r1)
367 /*********************************************************
368 32/64-bit Light-Weight-Syscall ABI
370 * - Indicates a hint for userspace inline asm
371 implementations.
373 Syscall number (caller-saves)
374 - %r20
375 * In asm clobber.
377 Argument registers (caller-saves)
378 - %r26, %r25, %r24, %r23, %r22
379 * In asm input.
381 Return registers (caller-saves)
382 - %r28 (return), %r21 (errno)
383 * In asm output.
385 Caller-saves registers
386 - %r1, %r27, %r29
387 - %r2 (return pointer)
388 - %r31 (ble link register)
389 * In asm clobber.
391 Callee-saves registers
392 - %r3-%r18
393 - %r30 (stack pointer)
394 * Not in asm clobber.
396 If userspace is 32-bit:
397 Callee-saves registers
398 - %r19 (32-bit PIC register)
400 Differences from 32-bit calling convention:
401 - Syscall number in %r20
402 - Additional argument register %r22 (arg4)
403 - Callee-saves %r19.
405 If userspace is 64-bit:
406 Callee-saves registers
407 - %r27 (64-bit PIC register)
409 Differences from 64-bit calling convention:
410 - Syscall number in %r20
411 - Additional argument register %r22 (arg4)
412 - Callee-saves %r27.
414 Error codes returned by entry path:
416 ENOSYS - r20 was an invalid LWS number.
418 *********************************************************/
419 lws_start:
420 /* Gate and ensure we return to userspace */
421 gate .+8, %r0
422 depi 3, 31, 2, %r31 /* Ensure we return to userspace */
424 #ifdef CONFIG_64BIT
425 /* FIXME: If we are a 64-bit kernel just
426 * turn this on unconditionally.
427 */
428 ssm PSW_SM_W, %r1
429 extrd,u %r1,PSW_W_BIT,1,%r1
430 /* sp must be aligned on 4, so deposit the W bit setting into
431 * the bottom of sp temporarily */
432 or,ev %r1,%r30,%r30
434 /* Clip LWS number to a 32-bit value always */
435 depdi 0, 31, 32, %r20
436 #endif
438 /* Is the lws entry number valid? */
439 comiclr,>>= __NR_lws_entries, %r20, %r0
440 b,n lws_exit_nosys
442 /* WARNING: Trashing sr2 and sr3 */
443 mfsp %sr7,%r1 /* get userspace into sr3 */
444 mtsp %r1,%sr3
445 mtsp %r0,%sr2 /* get kernel space into sr2 */
447 /* Load table start */
448 ldil L%lws_table, %r1
449 ldo R%lws_table(%r1), %r28 /* Scratch use of r28 */
450 LDREGX %r20(%sr2,r28), %r21 /* Scratch use of r21 */
452 /* Jump to lws, lws table pointers already relocated */
453 be,n 0(%sr2,%r21)
455 lws_exit_nosys:
456 ldo -ENOSYS(%r0),%r21 /* set errno */
457 /* Fall through: Return to userspace */
459 lws_exit:
460 #ifdef CONFIG_64BIT
461 /* decide whether to reset the wide mode bit
462 *
463 * For a syscall, the W bit is stored in the lowest bit
464 * of sp. Extract it and reset W if it is zero */
465 extrd,u,*<> %r30,63,1,%r1
466 rsm PSW_SM_W, %r0
467 /* now reset the lowest bit of sp if it was set */
468 xor %r30,%r1,%r30
469 #endif
470 be,n 0(%sr3, %r31)
474 /***************************************************
475 Implementing CAS as an atomic operation:
477 %r26 - Address to examine
478 %r25 - Old value to check (old)
479 %r24 - New value to set (new)
480 %r28 - Return prev through this register.
481 %r21 - Kernel error code
483 If debugging is DISabled:
485 %r21 has the following meanings:
487 EAGAIN - CAS is busy, ldcw failed, try again.
488 EFAULT - Read or write failed.
490 If debugging is enabled:
492 EDEADLOCK - CAS called recursively.
493 EAGAIN && r28 == 1 - CAS is busy. Lock contended.
494 EAGAIN && r28 == 2 - CAS is busy. ldcw failed.
495 EFAULT - Read or write failed.
497 Scratch: r20, r28, r1
499 ****************************************************/
501 /* Do not enable LWS debugging */
502 #define ENABLE_LWS_DEBUG 0
504 /* ELF64 Process entry path */
505 lws_compare_and_swap64:
506 #ifdef CONFIG_64BIT
507 b,n lws_compare_and_swap
508 #else
509 /* If we are not a 64-bit kernel, then we don't
510 * have 64-bit input registers, and calling
511 * the 64-bit LWS CAS returns ENOSYS.
512 */
513 b,n lws_exit_nosys
514 #endif
516 /* ELF32 Process entry path */
517 lws_compare_and_swap32:
518 #ifdef CONFIG_64BIT
519 /* Clip all the input registers */
520 depdi 0, 31, 32, %r26
521 depdi 0, 31, 32, %r25
522 depdi 0, 31, 32, %r24
523 #endif
525 lws_compare_and_swap:
526 #ifdef CONFIG_SMP
527 /* Load start of lock table */
528 ldil L%lws_lock_start, %r20
529 ldo R%lws_lock_start(%r20), %r28
531 /* Extract four bits from r26 and hash lock (Bits 4-7) */
532 extru %r26, 27, 4, %r20
534 /* Find lock to use, the hash is either one of 0 to
535 15, multiplied by 16 (keep it 16-byte aligned)
536 and add to the lock table offset. */
537 shlw %r20, 4, %r20
538 add %r20, %r28, %r20
540 # if ENABLE_LWS_DEBUG
541 /*
542 DEBUG, check for deadlock!
543 If the thread register values are the same
544 then we were the one that locked it last and
545 this is a recurisve call that will deadlock.
546 We *must* giveup this call and fail.
547 */
548 ldw 4(%sr2,%r20), %r28 /* Load thread register */
549 /* WARNING: If cr27 cycles to the same value we have problems */
550 mfctl %cr27, %r21 /* Get current thread register */
551 cmpb,<>,n %r21, %r28, cas_lock /* Called recursive? */
552 b lws_exit /* Return error! */
553 ldo -EDEADLOCK(%r0), %r21
554 cas_lock:
555 cmpb,=,n %r0, %r28, cas_nocontend /* Is nobody using it? */
556 ldo 1(%r0), %r28 /* 1st case */
557 b lws_exit /* Contended... */
558 ldo -EAGAIN(%r0), %r21 /* Spin in userspace */
559 cas_nocontend:
560 # endif
561 /* ENABLE_LWS_DEBUG */
563 LDCW 0(%sr2,%r20), %r28 /* Try to acquire the lock */
564 cmpb,<>,n %r0, %r28, cas_action /* Did we get it? */
565 cas_wouldblock:
566 ldo 2(%r0), %r28 /* 2nd case */
567 b lws_exit /* Contended... */
568 ldo -EAGAIN(%r0), %r21 /* Spin in userspace */
569 #endif
570 /* CONFIG_SMP */
572 /*
573 prev = *addr;
574 if ( prev == old )
575 *addr = new;
576 return prev;
577 */
579 /* NOTES:
580 This all works becuse intr_do_signal
581 and schedule both check the return iasq
582 and see that we are on the kernel page
583 so this process is never scheduled off
584 or is ever sent any signal of any sort,
585 thus it is wholly atomic from usrspaces
586 perspective
587 */
588 cas_action:
589 #if defined CONFIG_SMP && ENABLE_LWS_DEBUG
590 /* DEBUG */
591 mfctl %cr27, %r1
592 stw %r1, 4(%sr2,%r20)
593 #endif
594 /* The load and store could fail */
595 1: ldw 0(%sr3,%r26), %r28
596 sub,<> %r28, %r25, %r0
597 2: stw %r24, 0(%sr3,%r26)
598 #ifdef CONFIG_SMP
599 /* Free lock */
600 stw %r20, 0(%sr2,%r20)
601 # if ENABLE_LWS_DEBUG
602 /* Clear thread register indicator */
603 stw %r0, 4(%sr2,%r20)
604 # endif
605 #endif
606 /* Return to userspace, set no error */
607 b lws_exit
608 copy %r0, %r21
610 3:
611 /* Error occured on load or store */
612 #ifdef CONFIG_SMP
613 /* Free lock */
614 stw %r20, 0(%sr2,%r20)
615 # if ENABLE_LWS_DEBUG
616 stw %r0, 4(%sr2,%r20)
617 # endif
618 #endif
619 b lws_exit
620 ldo -EFAULT(%r0),%r21 /* set errno */
621 nop
622 nop
623 nop
624 nop
626 /* Two exception table entries, one for the load,
627 the other for the store. Either return -EFAULT.
628 Each of the entries must be relocated. */
629 .section __ex_table,"aw"
630 ASM_ULONG_INSN (1b - linux_gateway_page), (3b - linux_gateway_page)
631 ASM_ULONG_INSN (2b - linux_gateway_page), (3b - linux_gateway_page)
632 .previous
635 /* Make sure nothing else is placed on this page */
636 .align PAGE_SIZE
637 END(linux_gateway_page)
638 ENTRY(end_linux_gateway_page)
640 /* Relocate symbols assuming linux_gateway_page is mapped
641 to virtual address 0x0 */
643 #define LWS_ENTRY(_name_) ASM_ULONG_INSN (lws_##_name_ - linux_gateway_page)
645 .section .rodata,"a"
647 .align PAGE_SIZE
648 /* Light-weight-syscall table */
649 /* Start of lws table. */
650 ENTRY(lws_table)
651 LWS_ENTRY(compare_and_swap32) /* 0 - ELF32 Atomic compare and swap */
652 LWS_ENTRY(compare_and_swap64) /* 1 - ELF64 Atomic compare and swap */
653 END(lws_table)
654 /* End of lws table */
656 .align PAGE_SIZE
657 ENTRY(sys_call_table)
658 #include "syscall_table.S"
659 END(sys_call_table)
661 #ifdef CONFIG_64BIT
662 .align PAGE_SIZE
663 ENTRY(sys_call_table64)
664 #define SYSCALL_TABLE_64BIT
665 #include "syscall_table.S"
666 END(sys_call_table64)
667 #endif
669 #ifdef CONFIG_SMP
670 /*
671 All light-weight-syscall atomic operations
672 will use this set of locks
674 NOTE: The lws_lock_start symbol must be
675 at least 16-byte aligned for safe use
676 with ldcw.
677 */
678 .section .data
679 .align PAGE_SIZE
680 ENTRY(lws_lock_start)
681 /* lws locks */
682 .rept 16
683 /* Keep locks aligned at 16-bytes */
684 .word 1
685 .word 0
686 .word 0
687 .word 0
688 .endr
689 END(lws_lock_start)
690 .previous
691 #endif
692 /* CONFIG_SMP for lws_lock_start */
694 .end