| blob | 82a52b2fb13f296ef65726afc51b38f12e420047 |
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 0xb8, lws uses two 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 gate lws_start, %r0 /* increase privilege */
57 depi 3, 31, 2, %r31 /* Ensure we return into user mode. */
59 /* Fill from 0xb8 to 0xe0 */
60 .rept 10
61 KILL_INSN
62 .endr
64 /* This function MUST be located at 0xe0 for glibc's threading
65 mechanism to work. DO NOT MOVE THIS CODE EVER! */
66 set_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 */
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
78 /* This address must remain fixed at 0x100 for glibc's syscalls to work */
79 .align 256
80 linux_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 */
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
110 1:
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
117 ldo THREAD_SZ_ALGN+FRAME_SIZE(%r30),%r30 /* set up kernel stack */
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 */
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
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)
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 */
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 */
163 ldo TASK_PT_FR0(%r1), %r27 /* save fpregs from the kernel */
164 save_fp %r27 /* or potential task switch */
166 mfctl %cr11, %r27 /* i.e. SAR */
167 STREG %r27, TASK_PT_SAR(%r1)
169 loadgp
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
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
187 /* Note! We cannot use the syscall table that is mapped
188 nearby since the gateway page is mapped execute-only. */
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
204 LDREGX %r20(%r19), %r19
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
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. */
228 .Lsyscall_nosys:
229 syscall_nosys:
230 ldil L%syscall_exit,%r1
231 be R%syscall_exit(%sr7,%r1)
232 ldo -ENOSYS(%r0),%r28 /* set errno */
235 /* Warning! This trace code is a virtual duplicate of the code above so be
236 * sure to maintain both! */
237 .Ltracesys:
238 tracesys:
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 */
290 copy %r2,%r26
291 ldil L%do_syscall_trace_enter,%r1
292 ldil L%tracesys_next,%r2
293 be R%do_syscall_trace_enter(%sr7,%r1)
294 ldo R%tracesys_next(%r2),%r2
296 tracesys_next:
297 /* do_syscall_trace_enter either returned the syscallno, or -1L,
298 * so we skip restoring the PT_GR20 below, since we pulled it from
299 * task->thread.regs.gr[20] above.
300 */
301 copy %ret0,%r20
302 ldil L%sys_call_table,%r1
303 ldo R%sys_call_table(%r1), %r19
305 ldo -THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 /* get task ptr */
306 LDREG TI_TASK(%r1), %r1
307 LDREG TASK_PT_GR26(%r1), %r26 /* Restore the users args */
308 LDREG TASK_PT_GR25(%r1), %r25
309 LDREG TASK_PT_GR24(%r1), %r24
310 LDREG TASK_PT_GR23(%r1), %r23
311 #ifdef CONFIG_64BIT
312 LDREG TASK_PT_GR22(%r1), %r22
313 LDREG TASK_PT_GR21(%r1), %r21
314 ldo -16(%r30),%r29 /* Reference param save area */
315 #endif
317 comiclr,>>= __NR_Linux_syscalls, %r20, %r0
318 b,n .Lsyscall_nosys
320 LDREGX %r20(%r19), %r19
322 /* If this is a sys_rt_sigreturn call, and the signal was received
323 * when not in_syscall, then we want to return via syscall_exit_rfi,
324 * not syscall_exit. Signal no. in r20, in_syscall in r25 (see
325 * trampoline code in signal.c).
326 */
327 ldi __NR_rt_sigreturn,%r2
328 comb,= %r2,%r20,.Ltrace_rt_sigreturn
329 .Ltrace_in_syscall:
330 ldil L%tracesys_exit,%r2
331 be 0(%sr7,%r19)
332 ldo R%tracesys_exit(%r2),%r2
334 /* Do *not* call this function on the gateway page, because it
335 makes a direct call to syscall_trace. */
337 tracesys_exit:
338 ldo -THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 /* get task ptr */
339 LDREG TI_TASK(%r1), %r1
340 #ifdef CONFIG_64BIT
341 ldo -16(%r30),%r29 /* Reference param save area */
342 #endif
343 ldo TASK_REGS(%r1),%r26
344 bl do_syscall_trace_exit,%r2
345 STREG %r28,TASK_PT_GR28(%r1) /* save return value now */
346 ldo -THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 /* get task ptr */
347 LDREG TI_TASK(%r1), %r1
348 LDREG TASK_PT_GR28(%r1), %r28 /* Restore return val. */
350 ldil L%syscall_exit,%r1
351 be,n R%syscall_exit(%sr7,%r1)
353 .Ltrace_rt_sigreturn:
354 comib,<> 0,%r25,.Ltrace_in_syscall
355 ldil L%tracesys_sigexit,%r2
356 be 0(%sr7,%r19)
357 ldo R%tracesys_sigexit(%r2),%r2
359 tracesys_sigexit:
360 ldo -THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 /* get task ptr */
361 LDREG TI_TASK(%r1), %r1
362 #ifdef CONFIG_64BIT
363 ldo -16(%r30),%r29 /* Reference param save area */
364 #endif
365 bl do_syscall_trace_exit,%r2
366 ldo TASK_REGS(%r1),%r26
368 ldil L%syscall_exit_rfi,%r1
369 be,n R%syscall_exit_rfi(%sr7,%r1)
372 /*********************************************************
373 32/64-bit Light-Weight-Syscall ABI
375 * - Indicates a hint for userspace inline asm
376 implementations.
378 Syscall number (caller-saves)
379 - %r20
380 * In asm clobber.
382 Argument registers (caller-saves)
383 - %r26, %r25, %r24, %r23, %r22
384 * In asm input.
386 Return registers (caller-saves)
387 - %r28 (return), %r21 (errno)
388 * In asm output.
390 Caller-saves registers
391 - %r1, %r27, %r29
392 - %r2 (return pointer)
393 - %r31 (ble link register)
394 * In asm clobber.
396 Callee-saves registers
397 - %r3-%r18
398 - %r30 (stack pointer)
399 * Not in asm clobber.
401 If userspace is 32-bit:
402 Callee-saves registers
403 - %r19 (32-bit PIC register)
405 Differences from 32-bit calling convention:
406 - Syscall number in %r20
407 - Additional argument register %r22 (arg4)
408 - Callee-saves %r19.
410 If userspace is 64-bit:
411 Callee-saves registers
412 - %r27 (64-bit PIC register)
414 Differences from 64-bit calling convention:
415 - Syscall number in %r20
416 - Additional argument register %r22 (arg4)
417 - Callee-saves %r27.
419 Error codes returned by entry path:
421 ENOSYS - r20 was an invalid LWS number.
423 *********************************************************/
424 lws_start:
426 #ifdef CONFIG_64BIT
427 /* FIXME: If we are a 64-bit kernel just
428 * turn this on unconditionally.
429 */
430 ssm PSW_SM_W, %r1
431 extrd,u %r1,PSW_W_BIT,1,%r1
432 /* sp must be aligned on 4, so deposit the W bit setting into
433 * the bottom of sp temporarily */
434 or,ev %r1,%r30,%r30
436 /* Clip LWS number to a 32-bit value always */
437 depdi 0, 31, 32, %r20
438 #endif
440 /* Is the lws entry number valid? */
441 comiclr,>> __NR_lws_entries, %r20, %r0
442 b,n lws_exit_nosys
444 /* WARNING: Trashing sr2 and sr3 */
445 mfsp %sr7,%r1 /* get userspace into sr3 */
446 mtsp %r1,%sr3
447 mtsp %r0,%sr2 /* get kernel space into sr2 */
449 /* Load table start */
450 ldil L%lws_table, %r1
451 ldo R%lws_table(%r1), %r28 /* Scratch use of r28 */
452 LDREGX %r20(%sr2,r28), %r21 /* Scratch use of r21 */
454 /* Jump to lws, lws table pointers already relocated */
455 be,n 0(%sr2,%r21)
457 lws_exit_nosys:
458 ldo -ENOSYS(%r0),%r21 /* set errno */
459 /* Fall through: Return to userspace */
461 lws_exit:
462 #ifdef CONFIG_64BIT
463 /* decide whether to reset the wide mode bit
464 *
465 * For a syscall, the W bit is stored in the lowest bit
466 * of sp. Extract it and reset W if it is zero */
467 extrd,u,*<> %r30,63,1,%r1
468 rsm PSW_SM_W, %r0
469 /* now reset the lowest bit of sp if it was set */
470 xor %r30,%r1,%r30
471 #endif
472 be,n 0(%sr7, %r31)
476 /***************************************************
477 Implementing CAS as an atomic operation:
479 %r26 - Address to examine
480 %r25 - Old value to check (old)
481 %r24 - New value to set (new)
482 %r28 - Return prev through this register.
483 %r21 - Kernel error code
485 If debugging is DISabled:
487 %r21 has the following meanings:
489 EAGAIN - CAS is busy, ldcw failed, try again.
490 EFAULT - Read or write failed.
492 If debugging is enabled:
494 EDEADLOCK - CAS called recursively.
495 EAGAIN && r28 == 1 - CAS is busy. Lock contended.
496 EAGAIN && r28 == 2 - CAS is busy. ldcw failed.
497 EFAULT - Read or write failed.
499 Scratch: r20, r28, r1
501 ****************************************************/
503 /* Do not enable LWS debugging */
504 #define ENABLE_LWS_DEBUG 0
506 /* ELF64 Process entry path */
507 lws_compare_and_swap64:
508 #ifdef CONFIG_64BIT
509 b,n lws_compare_and_swap
510 #else
511 /* If we are not a 64-bit kernel, then we don't
512 * have 64-bit input registers, and calling
513 * the 64-bit LWS CAS returns ENOSYS.
514 */
515 b,n lws_exit_nosys
516 #endif
518 /* ELF32 Process entry path */
519 lws_compare_and_swap32:
520 #ifdef CONFIG_64BIT
521 /* Clip all the input registers */
522 depdi 0, 31, 32, %r26
523 depdi 0, 31, 32, %r25
524 depdi 0, 31, 32, %r24
525 #endif
527 lws_compare_and_swap:
528 /* Load start of lock table */
529 ldil L%lws_lock_start, %r20
530 ldo R%lws_lock_start(%r20), %r28
532 /* Extract four bits from r26 and hash lock (Bits 4-7) */
533 extru %r26, 27, 4, %r20
535 /* Find lock to use, the hash is either one of 0 to
536 15, multiplied by 16 (keep it 16-byte aligned)
537 and add to the lock table offset. */
538 shlw %r20, 4, %r20
539 add %r20, %r28, %r20
541 # if ENABLE_LWS_DEBUG
542 /*
543 DEBUG, check for deadlock!
544 If the thread register values are the same
545 then we were the one that locked it last and
546 this is a recurisve call that will deadlock.
547 We *must* giveup this call and fail.
548 */
549 ldw 4(%sr2,%r20), %r28 /* Load thread register */
550 /* WARNING: If cr27 cycles to the same value we have problems */
551 mfctl %cr27, %r21 /* Get current thread register */
552 cmpb,<>,n %r21, %r28, cas_lock /* Called recursive? */
553 b lws_exit /* Return error! */
554 ldo -EDEADLOCK(%r0), %r21
555 cas_lock:
556 cmpb,=,n %r0, %r28, cas_nocontend /* Is nobody using it? */
557 ldo 1(%r0), %r28 /* 1st case */
558 b lws_exit /* Contended... */
559 ldo -EAGAIN(%r0), %r21 /* Spin in userspace */
560 cas_nocontend:
561 # endif
562 /* ENABLE_LWS_DEBUG */
564 LDCW 0(%sr2,%r20), %r28 /* Try to acquire the lock */
565 cmpb,<>,n %r0, %r28, cas_action /* Did we get it? */
566 cas_wouldblock:
567 ldo 2(%r0), %r28 /* 2nd case */
568 b lws_exit /* Contended... */
569 ldo -EAGAIN(%r0), %r21 /* Spin in userspace */
571 /*
572 prev = *addr;
573 if ( prev == old )
574 *addr = new;
575 return prev;
576 */
578 /* NOTES:
579 This all works becuse intr_do_signal
580 and schedule both check the return iasq
581 and see that we are on the kernel page
582 so this process is never scheduled off
583 or is ever sent any signal of any sort,
584 thus it is wholly atomic from usrspaces
585 perspective
586 */
587 cas_action:
588 #if defined CONFIG_SMP && ENABLE_LWS_DEBUG
589 /* DEBUG */
590 mfctl %cr27, %r1
591 stw %r1, 4(%sr2,%r20)
592 #endif
593 /* The load and store could fail */
594 1: ldw 0(%sr3,%r26), %r28
595 sub,<> %r28, %r25, %r0
596 2: stw %r24, 0(%sr3,%r26)
597 /* Free lock */
598 stw %r20, 0(%sr2,%r20)
599 #if ENABLE_LWS_DEBUG
600 /* Clear thread register indicator */
601 stw %r0, 4(%sr2,%r20)
602 #endif
603 /* Return to userspace, set no error */
604 b lws_exit
605 copy %r0, %r21
607 3:
608 /* Error occurred on load or store */
609 /* Free lock */
610 stw %r20, 0(%sr2,%r20)
611 #if ENABLE_LWS_DEBUG
612 stw %r0, 4(%sr2,%r20)
613 #endif
614 b lws_exit
615 ldo -EFAULT(%r0),%r21 /* set errno */
616 nop
617 nop
618 nop
619 nop
621 /* Two exception table entries, one for the load,
622 the other for the store. Either return -EFAULT.
623 Each of the entries must be relocated. */
624 .section __ex_table,"aw"
625 ASM_ULONG_INSN (1b - linux_gateway_page), (3b - linux_gateway_page)
626 ASM_ULONG_INSN (2b - linux_gateway_page), (3b - linux_gateway_page)
627 .previous
630 /* Make sure nothing else is placed on this page */
631 .align PAGE_SIZE
632 END(linux_gateway_page)
633 ENTRY(end_linux_gateway_page)
635 /* Relocate symbols assuming linux_gateway_page is mapped
636 to virtual address 0x0 */
638 #define LWS_ENTRY(_name_) ASM_ULONG_INSN (lws_##_name_ - linux_gateway_page)
640 .section .rodata,"a"
642 .align PAGE_SIZE
643 /* Light-weight-syscall table */
644 /* Start of lws table. */
645 ENTRY(lws_table)
646 LWS_ENTRY(compare_and_swap32) /* 0 - ELF32 Atomic compare and swap */
647 LWS_ENTRY(compare_and_swap64) /* 1 - ELF64 Atomic compare and swap */
648 END(lws_table)
649 /* End of lws table */
651 .align PAGE_SIZE
652 ENTRY(sys_call_table)
653 #include "syscall_table.S"
654 END(sys_call_table)
656 #ifdef CONFIG_64BIT
657 .align PAGE_SIZE
658 ENTRY(sys_call_table64)
659 #define SYSCALL_TABLE_64BIT
660 #include "syscall_table.S"
661 END(sys_call_table64)
662 #endif
664 /*
665 All light-weight-syscall atomic operations
666 will use this set of locks
668 NOTE: The lws_lock_start symbol must be
669 at least 16-byte aligned for safe use
670 with ldcw.
671 */
672 .section .data
673 .align PAGE_SIZE
674 ENTRY(lws_lock_start)
675 /* lws locks */
676 .rept 16
677 /* Keep locks aligned at 16-bytes */
678 .word 1
679 .word 0
680 .word 0
681 .word 0
682 .endr
683 END(lws_lock_start)
684 .previous
686 .end