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 16#include <asm/assembly.h> 17#include <asm/processor.h> 18 19 /* We fill the empty parts of the gateway page with 20 * something that will kill the kernel or a 21 * userspace application. 22 */ 23#define KILL_INSN break 0,0 24 25#ifdef CONFIG_64BIT 26 .level 2.0w 27#else 28 .level 1.1 29#endif 30 31 .text 32 33 .import syscall_exit,code 34 .import syscall_exit_rfi,code 35 .export linux_gateway_page 36 37 /* Linux gateway page is aliased to virtual page 0 in the kernel 38 * address space. Since it is a gateway page it cannot be 39 * dereferenced, so null pointers will still fault. We start 40 * the actual entry point at 0x100. We put break instructions 41 * at the beginning of the page to trap null indirect function 42 * pointers. 43 */ 44 45 .align ASM_PAGE_SIZE 46linux_gateway_page: 47 48 /* ADDRESS 0x00 to 0xb0 = 176 bytes / 4 bytes per insn = 44 insns */ 49 .rept 44 50 KILL_INSN 51 .endr 52 53 /* ADDRESS 0xb0 to 0xb4, lws uses 1 insns for entry */ 54 /* Light-weight-syscall entry must always be located at 0xb0 */ 55 /* WARNING: Keep this number updated with table size changes */ 56#define __NR_lws_entries (2) 57 58lws_entry: 59 /* Unconditional branch to lws_start, located on the 60 same gateway page */ 61 b,n lws_start 62 63 /* Fill from 0xb4 to 0xe0 */ 64 .rept 11 65 KILL_INSN 66 .endr 67 68 /* This function MUST be located at 0xe0 for glibc's threading 69 mechanism to work. DO NOT MOVE THIS CODE EVER! */ 70set_thread_pointer: 71 gate .+8, %r0 /* increase privilege */ 72 depi 3, 31, 2, %r31 /* Ensure we return into user mode. */ 73 be 0(%sr7,%r31) /* return to user space */ 74 mtctl %r26, %cr27 /* move arg0 to the control register */ 75 76 /* Increase the chance of trapping if random jumps occur to this 77 address, fill from 0xf0 to 0x100 */ 78 .rept 4 79 KILL_INSN 80 .endr 81 82/* This address must remain fixed at 0x100 for glibc's syscalls to work */ 83 .align 256 84linux_gateway_entry: 85 gate .+8, %r0 /* become privileged */ 86 mtsp %r0,%sr4 /* get kernel space into sr4 */ 87 mtsp %r0,%sr5 /* get kernel space into sr5 */ 88 mtsp %r0,%sr6 /* get kernel space into sr6 */ 89 mfsp %sr7,%r1 /* save user sr7 */ 90 mtsp %r1,%sr3 /* and store it in sr3 */ 91 92#ifdef CONFIG_64BIT 93 /* for now we can *always* set the W bit on entry to the syscall 94 * since we don't support wide userland processes. We could 95 * also save the current SM other than in r0 and restore it on 96 * exit from the syscall, and also use that value to know 97 * whether to do narrow or wide syscalls. -PB 98 */ 99 ssm PSW_SM_W, %r1 100 extrd,u %r1,PSW_W_BIT,1,%r1 101 /* sp must be aligned on 4, so deposit the W bit setting into 102 * the bottom of sp temporarily */ 103 or,ev %r1,%r30,%r30 104 b,n 1f 105 /* The top halves of argument registers must be cleared on syscall 106 * entry from narrow executable. 107 */ 108 depdi 0, 31, 32, %r26 109 depdi 0, 31, 32, %r25 110 depdi 0, 31, 32, %r24 111 depdi 0, 31, 32, %r23 112 depdi 0, 31, 32, %r22 113 depdi 0, 31, 32, %r21 1141: 115#endif 116 mfctl %cr30,%r1 117 xor %r1,%r30,%r30 /* ye olde xor trick */ 118 xor %r1,%r30,%r1 119 xor %r1,%r30,%r30 120 121 ldo THREAD_SZ_ALGN+FRAME_SIZE(%r30),%r30 /* set up kernel stack */ 122 123 /* N.B.: It is critical that we don't set sr7 to 0 until r30 124 * contains a valid kernel stack pointer. It is also 125 * critical that we don't start using the kernel stack 126 * until after sr7 has been set to 0. 127 */ 128 129 mtsp %r0,%sr7 /* get kernel space into sr7 */ 130 STREGM %r1,FRAME_SIZE(%r30) /* save r1 (usp) here for now */ 131 mfctl %cr30,%r1 /* get task ptr in %r1 */ 132 LDREG TI_TASK(%r1),%r1 133 134 /* Save some registers for sigcontext and potential task 135 switch (see entry.S for the details of which ones are 136 saved/restored). TASK_PT_PSW is zeroed so we can see whether 137 a process is on a syscall or not. For an interrupt the real 138 PSW value is stored. This is needed for gdb and sys_ptrace. */ 139 STREG %r0, TASK_PT_PSW(%r1) 140 STREG %r2, TASK_PT_GR2(%r1) /* preserve rp */ 141 STREG %r19, TASK_PT_GR19(%r1) 142 143 LDREGM -FRAME_SIZE(%r30), %r2 /* get users sp back */ 144#ifdef CONFIG_64BIT 145 extrd,u %r2,63,1,%r19 /* W hidden in bottom bit */ 146#if 0 147 xor %r19,%r2,%r2 /* clear bottom bit */ 148 depd,z %r19,1,1,%r19 149 std %r19,TASK_PT_PSW(%r1) 150#endif 151#endif 152 STREG %r2, TASK_PT_GR30(%r1) /* ... and save it */ 153 154 STREG %r20, TASK_PT_GR20(%r1) /* Syscall number */ 155 STREG %r21, TASK_PT_GR21(%r1) 156 STREG %r22, TASK_PT_GR22(%r1) 157 STREG %r23, TASK_PT_GR23(%r1) /* 4th argument */ 158 STREG %r24, TASK_PT_GR24(%r1) /* 3rd argument */ 159 STREG %r25, TASK_PT_GR25(%r1) /* 2nd argument */ 160 STREG %r26, TASK_PT_GR26(%r1) /* 1st argument */ 161 STREG %r27, TASK_PT_GR27(%r1) /* user dp */ 162 STREG %r28, TASK_PT_GR28(%r1) /* return value 0 */ 163 STREG %r28, TASK_PT_ORIG_R28(%r1) /* return value 0 (saved for signals) */ 164 STREG %r29, TASK_PT_GR29(%r1) /* return value 1 */ 165 STREG %r31, TASK_PT_GR31(%r1) /* preserve syscall return ptr */ 166 167 ldo TASK_PT_FR0(%r1), %r27 /* save fpregs from the kernel */ 168 save_fp %r27 /* or potential task switch */ 169 170 mfctl %cr11, %r27 /* i.e. SAR */ 171 STREG %r27, TASK_PT_SAR(%r1) 172 173 loadgp 174 175#ifdef CONFIG_64BIT 176 ldo -16(%r30),%r29 /* Reference param save area */ 177 copy %r19,%r2 /* W bit back to r2 */ 178#else 179 /* no need to save these on stack in wide mode because the first 8 180 * args are passed in registers */ 181 stw %r22, -52(%r30) /* 5th argument */ 182 stw %r21, -56(%r30) /* 6th argument */ 183#endif 184 185 /* Are we being ptraced? */ 186 mfctl %cr30, %r1 187 LDREG TI_TASK(%r1),%r1 188 LDREG TASK_PTRACE(%r1), %r1 189 bb,<,n %r1,31,.Ltracesys 190 191 /* Note! We cannot use the syscall table that is mapped 192 nearby since the gateway page is mapped execute-only. */ 193 194#ifdef CONFIG_64BIT 195 ldil L%sys_call_table, %r1 196 or,= %r2,%r2,%r2 197 addil L%(sys_call_table64-sys_call_table), %r1 198 ldo R%sys_call_table(%r1), %r19 199 or,= %r2,%r2,%r2 200 ldo R%sys_call_table64(%r1), %r19 201#else 202 ldil L%sys_call_table, %r1 203 ldo R%sys_call_table(%r1), %r19 204#endif 205 comiclr,>>= __NR_Linux_syscalls, %r20, %r0 206 b,n .Lsyscall_nosys 207 208 LDREGX %r20(%r19), %r19 209 210 /* If this is a sys_rt_sigreturn call, and the signal was received 211 * when not in_syscall, then we want to return via syscall_exit_rfi, 212 * not syscall_exit. Signal no. in r20, in_syscall in r25 (see 213 * trampoline code in signal.c). 214 */ 215 ldi __NR_rt_sigreturn,%r2 216 comb,= %r2,%r20,.Lrt_sigreturn 217.Lin_syscall: 218 ldil L%syscall_exit,%r2 219 be 0(%sr7,%r19) 220 ldo R%syscall_exit(%r2),%r2 221.Lrt_sigreturn: 222 comib,<> 0,%r25,.Lin_syscall 223 ldil L%syscall_exit_rfi,%r2 224 be 0(%sr7,%r19) 225 ldo R%syscall_exit_rfi(%r2),%r2 226 227 /* Note! Because we are not running where we were linked, any 228 calls to functions external to this file must be indirect. To 229 be safe, we apply the opposite rule to functions within this 230 file, with local labels given to them to ensure correctness. */ 231 232.Lsyscall_nosys: 233syscall_nosys: 234 ldil L%syscall_exit,%r1 235 be R%syscall_exit(%sr7,%r1) 236 ldo -ENOSYS(%r0),%r28 /* set errno */ 237 238 239/* Warning! This trace code is a virtual duplicate of the code above so be 240 * sure to maintain both! */ 241.Ltracesys: 242tracesys: 243 /* Need to save more registers so the debugger can see where we 244 * are. This saves only the lower 8 bits of PSW, so that the C 245 * bit is still clear on syscalls, and the D bit is set if this 246 * full register save path has been executed. We check the D 247 * bit on syscall_return_rfi to determine which registers to 248 * restore. An interrupt results in a full PSW saved with the 249 * C bit set, a non-straced syscall entry results in C and D clear 250 * in the saved PSW. 251 */ 252 ldo -THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 /* get task ptr */ 253 LDREG TI_TASK(%r1), %r1 254 ssm 0,%r2 255 STREG %r2,TASK_PT_PSW(%r1) /* Lower 8 bits only!! */ 256 mfsp %sr0,%r2 257 STREG %r2,TASK_PT_SR0(%r1) 258 mfsp %sr1,%r2 259 STREG %r2,TASK_PT_SR1(%r1) 260 mfsp %sr2,%r2 261 STREG %r2,TASK_PT_SR2(%r1) 262 mfsp %sr3,%r2 263 STREG %r2,TASK_PT_SR3(%r1) 264 STREG %r2,TASK_PT_SR4(%r1) 265 STREG %r2,TASK_PT_SR5(%r1) 266 STREG %r2,TASK_PT_SR6(%r1) 267 STREG %r2,TASK_PT_SR7(%r1) 268 STREG %r2,TASK_PT_IASQ0(%r1) 269 STREG %r2,TASK_PT_IASQ1(%r1) 270 LDREG TASK_PT_GR31(%r1),%r2 271 STREG %r2,TASK_PT_IAOQ0(%r1) 272 ldo 4(%r2),%r2 273 STREG %r2,TASK_PT_IAOQ1(%r1) 274 ldo TASK_REGS(%r1),%r2 275 /* reg_save %r2 */ 276 STREG %r3,PT_GR3(%r2) 277 STREG %r4,PT_GR4(%r2) 278 STREG %r5,PT_GR5(%r2) 279 STREG %r6,PT_GR6(%r2) 280 STREG %r7,PT_GR7(%r2) 281 STREG %r8,PT_GR8(%r2) 282 STREG %r9,PT_GR9(%r2) 283 STREG %r10,PT_GR10(%r2) 284 STREG %r11,PT_GR11(%r2) 285 STREG %r12,PT_GR12(%r2) 286 STREG %r13,PT_GR13(%r2) 287 STREG %r14,PT_GR14(%r2) 288 STREG %r15,PT_GR15(%r2) 289 STREG %r16,PT_GR16(%r2) 290 STREG %r17,PT_GR17(%r2) 291 STREG %r18,PT_GR18(%r2) 292 /* Finished saving things for the debugger */ 293 294 ldil L%syscall_trace,%r1 295 ldil L%tracesys_next,%r2 296 be R%syscall_trace(%sr7,%r1) 297 ldo R%tracesys_next(%r2),%r2 298 299tracesys_next: 300 ldil L%sys_call_table,%r1 301 ldo R%sys_call_table(%r1), %r19 302 303 ldo -THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 /* get task ptr */ 304 LDREG TI_TASK(%r1), %r1 305 LDREG TASK_PT_GR20(%r1), %r20 306 LDREG TASK_PT_GR26(%r1), %r26 /* Restore the users args */ 307 LDREG TASK_PT_GR25(%r1), %r25 308 LDREG TASK_PT_GR24(%r1), %r24 309 LDREG TASK_PT_GR23(%r1), %r23 310#ifdef CONFIG_64BIT 311 LDREG TASK_PT_GR22(%r1), %r22 312 LDREG TASK_PT_GR21(%r1), %r21 313 ldo -16(%r30),%r29 /* Reference param save area */ 314#endif 315 316 comiclr,>>= __NR_Linux_syscalls, %r20, %r0 317 b,n .Lsyscall_nosys 318 319 LDREGX %r20(%r19), %r19 320 321 /* If this is a sys_rt_sigreturn call, and the signal was received 322 * when not in_syscall, then we want to return via syscall_exit_rfi, 323 * not syscall_exit. Signal no. in r20, in_syscall in r25 (see 324 * trampoline code in signal.c). 325 */ 326 ldi __NR_rt_sigreturn,%r2 327 comb,= %r2,%r20,.Ltrace_rt_sigreturn 328.Ltrace_in_syscall: 329 ldil L%tracesys_exit,%r2 330 be 0(%sr7,%r19) 331 ldo R%tracesys_exit(%r2),%r2 332 333 /* Do *not* call this function on the gateway page, because it 334 makes a direct call to syscall_trace. */ 335 336tracesys_exit: 337 ldo -THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 /* get task ptr */ 338 LDREG TI_TASK(%r1), %r1 339#ifdef CONFIG_64BIT 340 ldo -16(%r30),%r29 /* Reference param save area */ 341#endif 342 bl syscall_trace, %r2 343 STREG %r28,TASK_PT_GR28(%r1) /* save return value now */ 344 ldo -THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 /* get task ptr */ 345 LDREG TI_TASK(%r1), %r1 346 LDREG TASK_PT_GR28(%r1), %r28 /* Restore return val. */ 347 348 ldil L%syscall_exit,%r1 349 be,n R%syscall_exit(%sr7,%r1) 350 351.Ltrace_rt_sigreturn: 352 comib,<> 0,%r25,.Ltrace_in_syscall 353 ldil L%tracesys_sigexit,%r2 354 be 0(%sr7,%r19) 355 ldo R%tracesys_sigexit(%r2),%r2 356 357tracesys_sigexit: 358 ldo -THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 /* get task ptr */ 359 LDREG 0(%r1), %r1 360#ifdef CONFIG_64BIT 361 ldo -16(%r30),%r29 /* Reference param save area */ 362#endif 363 bl syscall_trace, %r2 364 nop 365 366 ldil L%syscall_exit_rfi,%r1 367 be,n R%syscall_exit_rfi(%sr7,%r1) 368 369 370 /********************************************************* 371 Light-weight-syscall code 372 373 r20 - lws number 374 r26,r25,r24,r23,r22 - Input registers 375 r28 - Function return register 376 r21 - Error code. 377 378 Scracth: Any of the above that aren't being 379 currently used, including r1. 380 381 Return pointer: r31 (Not usable) 382 383 Error codes returned by entry path: 384 385 ENOSYS - r20 was an invalid LWS number. 386 387 *********************************************************/ 388lws_start: 389 /* Gate and ensure we return to userspace */ 390 gate .+8, %r0 391 depi 3, 31, 2, %r31 /* Ensure we return to userspace */ 392 393#ifdef CONFIG_64BIT 394 /* FIXME: If we are a 64-bit kernel just 395 * turn this on unconditionally. 396 */ 397 ssm PSW_SM_W, %r1 398 extrd,u %r1,PSW_W_BIT,1,%r1 399 /* sp must be aligned on 4, so deposit the W bit setting into 400 * the bottom of sp temporarily */ 401 or,ev %r1,%r30,%r30 402 403 /* Clip LWS number to a 32-bit value always */ 404 depdi 0, 31, 32, %r20 405#endif 406 407 /* Is the lws entry number valid? */ 408 comiclr,>>= __NR_lws_entries, %r20, %r0 409 b,n lws_exit_nosys 410 411 /* WARNING: Trashing sr2 and sr3 */ 412 mfsp %sr7,%r1 /* get userspace into sr3 */ 413 mtsp %r1,%sr3 414 mtsp %r0,%sr2 /* get kernel space into sr2 */ 415 416 /* Load table start */ 417 ldil L%lws_table, %r1 418 ldo R%lws_table(%r1), %r28 /* Scratch use of r28 */ 419 LDREGX %r20(%sr2,r28), %r21 /* Scratch use of r21 */ 420 421 /* Jump to lws, lws table pointers already relocated */ 422 be,n 0(%sr2,%r21) 423 424lws_exit_nosys: 425 ldo -ENOSYS(%r0),%r21 /* set errno */ 426 /* Fall through: Return to userspace */ 427 428lws_exit: 429#ifdef CONFIG_64BIT 430 /* decide whether to reset the wide mode bit 431 * 432 * For a syscall, the W bit is stored in the lowest bit 433 * of sp. Extract it and reset W if it is zero */ 434 extrd,u,*<> %r30,63,1,%r1 435 rsm PSW_SM_W, %r0 436 /* now reset the lowest bit of sp if it was set */ 437 xor %r30,%r1,%r30 438#endif 439 be,n 0(%sr3, %r31) 440 441 442 443 /*************************************************** 444 Implementing CAS as an atomic operation: 445 446 %r26 - Address to examine 447 %r25 - Old value to check (old) 448 %r24 - New value to set (new) 449 %r28 - Return prev through this register. 450 %r21 - Kernel error code 451 452 If debugging is DISabled: 453 454 %r21 has the following meanings: 455 456 EAGAIN - CAS is busy, ldcw failed, try again. 457 EFAULT - Read or write failed. 458 459 If debugging is enabled: 460 461 EDEADLOCK - CAS called recursively. 462 EAGAIN && r28 == 1 - CAS is busy. Lock contended. 463 EAGAIN && r28 == 2 - CAS is busy. ldcw failed. 464 EFAULT - Read or write failed. 465 466 Scratch: r20, r28, r1 467 468 ****************************************************/ 469 470 /* Do not enable LWS debugging */ 471#define ENABLE_LWS_DEBUG 0 472 473 /* ELF64 Process entry path */ 474lws_compare_and_swap64: 475#ifdef CONFIG_64BIT 476 b,n lws_compare_and_swap 477#else 478 /* If we are not a 64-bit kernel, then we don't 479 * implement having 64-bit input registers 480 */ 481 b,n lws_exit_nosys 482#endif 483 484 /* ELF32 Process entry path */ 485lws_compare_and_swap32: 486#ifdef CONFIG_64BIT 487 /* Clip all the input registers */ 488 depdi 0, 31, 32, %r26 489 depdi 0, 31, 32, %r25 490 depdi 0, 31, 32, %r24 491#endif 492 493lws_compare_and_swap: 494#ifdef CONFIG_SMP 495 /* Load start of lock table */ 496 ldil L%lws_lock_start, %r20 497 ldo R%lws_lock_start(%r20), %r28 498 499 /* Extract four bits from r26 and hash lock (Bits 4-7) */ 500 extru %r26, 27, 4, %r20 501 502 /* Find lock to use, the hash is either one of 0 to 503 15, multiplied by 16 (keep it 16-byte aligned) 504 and add to the lock table offset. */ 505 shlw %r20, 4, %r20 506 add %r20, %r28, %r20 507 508# ifdef ENABLE_LWS_DEBUG 509 /* 510 DEBUG, check for deadlock! 511 If the thread register values are the same 512 then we were the one that locked it last and 513 this is a recurisve call that will deadlock. 514 We *must* giveup this call and fail. 515 */ 516 ldw 4(%sr2,%r20), %r28 /* Load thread register */ 517 /* WARNING: If cr27 cycles to the same value we have problems */ 518 mfctl %cr27, %r21 /* Get current thread register */ 519 cmpb,<>,n %r21, %r28, cas_lock /* Called recursive? */ 520 b lws_exit /* Return error! */ 521 ldo -EDEADLOCK(%r0), %r21 522cas_lock: 523 cmpb,=,n %r0, %r28, cas_nocontend /* Is nobody using it? */ 524 ldo 1(%r0), %r28 /* 1st case */ 525 b lws_exit /* Contended... */ 526 ldo -EAGAIN(%r0), %r21 /* Spin in userspace */ 527cas_nocontend: 528# endif 529/* ENABLE_LWS_DEBUG */ 530 531 LDCW 0(%sr2,%r20), %r28 /* Try to acquire the lock */ 532 cmpb,<>,n %r0, %r28, cas_action /* Did we get it? */ 533cas_wouldblock: 534 ldo 2(%r0), %r28 /* 2nd case */ 535 b lws_exit /* Contended... */ 536 ldo -EAGAIN(%r0), %r21 /* Spin in userspace */ 537#endif 538/* CONFIG_SMP */ 539 540 /* 541 prev = *addr; 542 if ( prev == old ) 543 *addr = new; 544 return prev; 545 */ 546 547 /* NOTES: 548 This all works becuse intr_do_signal 549 and schedule both check the return iasq 550 and see that we are on the kernel page 551 so this process is never scheduled off 552 or is ever sent any signal of any sort, 553 thus it is wholly atomic from usrspaces 554 perspective 555 */ 556cas_action: 557#if defined CONFIG_SMP && defined ENABLE_LWS_DEBUG 558 /* DEBUG */ 559 mfctl %cr27, %r1 560 stw %r1, 4(%sr2,%r20) 561#endif 562 /* The load and store could fail */ 5631: ldw 0(%sr3,%r26), %r28 564 sub,<> %r28, %r25, %r0 5652: stw %r24, 0(%sr3,%r26) 566#ifdef CONFIG_SMP 567 /* Free lock */ 568 stw %r20, 0(%sr2,%r20) 569# ifdef ENABLE_LWS_DEBUG 570 /* Clear thread register indicator */ 571 stw %r0, 4(%sr2,%r20) 572# endif 573#endif 574 /* Return to userspace, set no error */ 575 b lws_exit 576 copy %r0, %r21 577 5783: 579 /* Error occured on load or store */ 580#ifdef CONFIG_SMP 581 /* Free lock */ 582 stw %r20, 0(%sr2,%r20) 583# ifdef ENABLE_LWS_DEBUG 584 stw %r0, 4(%sr2,%r20) 585# endif 586#endif 587 b lws_exit 588 ldo -EFAULT(%r0),%r21 /* set errno */ 589 nop 590 nop 591 nop 592 nop 593 594 /* Two exception table entries, one for the load, 595 the other for the store. Either return -EFAULT. 596 Each of the entries must be relocated. */ 597 .section __ex_table,"aw" 598#ifdef CONFIG_64BIT 599 /* Pad the address calculation */ 600 .word 0,(2b - linux_gateway_page) 601 .word 0,(3b - linux_gateway_page) 602#else 603 .word (2b - linux_gateway_page) 604 .word (3b - linux_gateway_page) 605#endif 606 .previous 607 608 .section __ex_table,"aw" 609#ifdef CONFIG_64BIT 610 /* Pad the address calculation */ 611 .word 0,(1b - linux_gateway_page) 612 .word 0,(3b - linux_gateway_page) 613#else 614 .word (1b - linux_gateway_page) 615 .word (3b - linux_gateway_page) 616#endif 617 .previous 618 619end_compare_and_swap: 620 621 /* Make sure nothing else is placed on this page */ 622 .align ASM_PAGE_SIZE 623 .export end_linux_gateway_page 624end_linux_gateway_page: 625 626 /* Relocate symbols assuming linux_gateway_page is mapped 627 to virtual address 0x0 */ 628#ifdef CONFIG_64BIT 629 /* FIXME: The code will always be on the gateay page 630 and thus it will be on the first 4k, the 631 assembler seems to think that the final 632 subtraction result is only a word in 633 length, so we pad the value. 634 */ 635#define LWS_ENTRY(_name_) .word 0,(lws_##_name_ - linux_gateway_page) 636#else 637#define LWS_ENTRY(_name_) .word (lws_##_name_ - linux_gateway_page) 638#endif 639 640 .section .rodata,"a" 641 642 .align ASM_PAGE_SIZE 643 /* Light-weight-syscall table */ 644 /* Start of lws table. */ 645 .export lws_table 646.Llws_table: 647lws_table: 648 LWS_ENTRY(compare_and_swap32) /* 0 - ELF32 Atomic compare and swap */ 649 LWS_ENTRY(compare_and_swap64) /* 1 - ELF64 Atomic compare and swap */ 650 /* End of lws table */ 651 652 .align ASM_PAGE_SIZE 653 .export sys_call_table 654.Lsys_call_table: 655sys_call_table: 656#include "syscall_table.S" 657 658#ifdef CONFIG_64BIT 659 .align ASM_PAGE_SIZE 660 .export sys_call_table64 661.Lsys_call_table64: 662sys_call_table64: 663#define SYSCALL_TABLE_64BIT 664#include "syscall_table.S" 665#endif 666 667#ifdef CONFIG_SMP 668 /* 669 All light-weight-syscall atomic operations 670 will use this set of locks 671 */ 672 .section .data 673 .align 4096 674 .export lws_lock_start 675.Llws_lock_start: 676lws_lock_start: 677 /* lws locks */ 678 .align 16 679 .rept 16 680 /* Keep locks aligned at 16-bytes */ 681 .word 1 682 .word 0 683 .word 0 684 .word 0 685 .endr 686 .previous 687#endif 688/* CONFIG_SMP for lws_lock_start */ 689 690.end 691 692 693