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#include <linux/config.h> /* for CONFIG_SMP */ 10 11#include <asm/asm-offsets.h> 12#include <asm/unistd.h> 13#include <asm/errno.h> 14#include <asm/psw.h> 15#include <asm/thread_info.h> 16 17#include <asm/assembly.h> 18#include <asm/processor.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#ifdef CONFIG_64BIT 27 .level 2.0w 28#else 29 .level 1.1 30#endif 31 32 .text 33 34 .import syscall_exit,code 35 .import syscall_exit_rfi,code 36 .export linux_gateway_page 37 38 /* Linux gateway page is aliased to virtual page 0 in the kernel 39 * address space. Since it is a gateway page it cannot be 40 * dereferenced, so null pointers will still fault. We start 41 * the actual entry point at 0x100. We put break instructions 42 * at the beginning of the page to trap null indirect function 43 * pointers. 44 */ 45 46 .align ASM_PAGE_SIZE 47linux_gateway_page: 48 49 /* ADDRESS 0x00 to 0xb0 = 176 bytes / 4 bytes per insn = 44 insns */ 50 .rept 44 51 KILL_INSN 52 .endr 53 54 /* ADDRESS 0xb0 to 0xb4, lws uses 1 insns for entry */ 55 /* Light-weight-syscall entry must always be located at 0xb0 */ 56 /* WARNING: Keep this number updated with table size changes */ 57#define __NR_lws_entries (2) 58 59lws_entry: 60 /* Unconditional branch to lws_start, located on the 61 same gateway page */ 62 b,n lws_start 63 64 /* Fill from 0xb4 to 0xe0 */ 65 .rept 11 66 KILL_INSN 67 .endr 68 69 /* This function MUST be located at 0xe0 for glibc's threading 70 mechanism to work. DO NOT MOVE THIS CODE EVER! */ 71set_thread_pointer: 72 gate .+8, %r0 /* increase privilege */ 73 depi 3, 31, 2, %r31 /* Ensure we return into user mode. */ 74 be 0(%sr7,%r31) /* return to user space */ 75 mtctl %r26, %cr27 /* move arg0 to the control register */ 76 77 /* Increase the chance of trapping if random jumps occur to this 78 address, fill from 0xf0 to 0x100 */ 79 .rept 4 80 KILL_INSN 81 .endr 82 83/* This address must remain fixed at 0x100 for glibc's syscalls to work */ 84 .align 256 85linux_gateway_entry: 86 gate .+8, %r0 /* become privileged */ 87 mtsp %r0,%sr4 /* get kernel space into sr4 */ 88 mtsp %r0,%sr5 /* get kernel space into sr5 */ 89 mtsp %r0,%sr6 /* get kernel space into sr6 */ 90 mfsp %sr7,%r1 /* save user sr7 */ 91 mtsp %r1,%sr3 /* and store it in sr3 */ 92 93#ifdef CONFIG_64BIT 94 /* for now we can *always* set the W bit on entry to the syscall 95 * since we don't support wide userland processes. We could 96 * also save the current SM other than in r0 and restore it on 97 * exit from the syscall, and also use that value to know 98 * whether to do narrow or wide syscalls. -PB 99 */ 100 ssm PSW_SM_W, %r1 101 extrd,u %r1,PSW_W_BIT,1,%r1 102 /* sp must be aligned on 4, so deposit the W bit setting into 103 * the bottom of sp temporarily */ 104 or,ev %r1,%r30,%r30 105 b,n 1f 106 /* The top halves of argument registers must be cleared on syscall 107 * entry from narrow executable. 108 */ 109 depdi 0, 31, 32, %r26 110 depdi 0, 31, 32, %r25 111 depdi 0, 31, 32, %r24 112 depdi 0, 31, 32, %r23 113 depdi 0, 31, 32, %r22 114 depdi 0, 31, 32, %r21 1151: 116#endif 117 mfctl %cr30,%r1 118 xor %r1,%r30,%r30 /* ye olde xor trick */ 119 xor %r1,%r30,%r1 120 xor %r1,%r30,%r30 121 122 ldo THREAD_SZ_ALGN+FRAME_SIZE(%r30),%r30 /* set up kernel stack */ 123 124 /* N.B.: It is critical that we don't set sr7 to 0 until r30 125 * contains a valid kernel stack pointer. It is also 126 * critical that we don't start using the kernel stack 127 * until after sr7 has been set to 0. 128 */ 129 130 mtsp %r0,%sr7 /* get kernel space into sr7 */ 131 STREGM %r1,FRAME_SIZE(%r30) /* save r1 (usp) here for now */ 132 mfctl %cr30,%r1 /* get task ptr in %r1 */ 133 LDREG TI_TASK(%r1),%r1 134 135 /* Save some registers for sigcontext and potential task 136 switch (see entry.S for the details of which ones are 137 saved/restored). TASK_PT_PSW is zeroed so we can see whether 138 a process is on a syscall or not. For an interrupt the real 139 PSW value is stored. This is needed for gdb and sys_ptrace. */ 140 STREG %r0, TASK_PT_PSW(%r1) 141 STREG %r2, TASK_PT_GR2(%r1) /* preserve rp */ 142 STREG %r19, TASK_PT_GR19(%r1) 143 144 LDREGM -FRAME_SIZE(%r30), %r2 /* get users sp back */ 145#ifdef CONFIG_64BIT 146 extrd,u %r2,63,1,%r19 /* W hidden in bottom bit */ 147#if 0 148 xor %r19,%r2,%r2 /* clear bottom bit */ 149 depd,z %r19,1,1,%r19 150 std %r19,TASK_PT_PSW(%r1) 151#endif 152#endif 153 STREG %r2, TASK_PT_GR30(%r1) /* ... and save it */ 154 155 STREG %r20, TASK_PT_GR20(%r1) /* Syscall number */ 156 STREG %r21, TASK_PT_GR21(%r1) 157 STREG %r22, TASK_PT_GR22(%r1) 158 STREG %r23, TASK_PT_GR23(%r1) /* 4th argument */ 159 STREG %r24, TASK_PT_GR24(%r1) /* 3rd argument */ 160 STREG %r25, TASK_PT_GR25(%r1) /* 2nd argument */ 161 STREG %r26, TASK_PT_GR26(%r1) /* 1st argument */ 162 STREG %r27, TASK_PT_GR27(%r1) /* user dp */ 163 STREG %r28, TASK_PT_GR28(%r1) /* return value 0 */ 164 STREG %r28, TASK_PT_ORIG_R28(%r1) /* return value 0 (saved for signals) */ 165 STREG %r29, TASK_PT_GR29(%r1) /* return value 1 */ 166 STREG %r31, TASK_PT_GR31(%r1) /* preserve syscall return ptr */ 167 168 ldo TASK_PT_FR0(%r1), %r27 /* save fpregs from the kernel */ 169 save_fp %r27 /* or potential task switch */ 170 171 mfctl %cr11, %r27 /* i.e. SAR */ 172 STREG %r27, TASK_PT_SAR(%r1) 173 174 loadgp 175 176#ifdef CONFIG_64BIT 177 ldo -16(%r30),%r29 /* Reference param save area */ 178 copy %r19,%r2 /* W bit back to r2 */ 179#else 180 /* no need to save these on stack in wide mode because the first 8 181 * args are passed in registers */ 182 stw %r22, -52(%r30) /* 5th argument */ 183 stw %r21, -56(%r30) /* 6th argument */ 184#endif 185 186 /* Are we being ptraced? */ 187 mfctl %cr30, %r1 188 LDREG TI_TASK(%r1),%r1 189 LDREG TASK_PTRACE(%r1), %r1 190 bb,<,n %r1,31,.Ltracesys 191 192 /* Note! We cannot use the syscall table that is mapped 193 nearby since the gateway page is mapped execute-only. */ 194 195#ifdef CONFIG_64BIT 196 ldil L%sys_call_table, %r1 197 or,= %r2,%r2,%r2 198 addil L%(sys_call_table64-sys_call_table), %r1 199 ldo R%sys_call_table(%r1), %r19 200 or,= %r2,%r2,%r2 201 ldo R%sys_call_table64(%r1), %r19 202#else 203 ldil L%sys_call_table, %r1 204 ldo R%sys_call_table(%r1), %r19 205#endif 206 comiclr,>>= __NR_Linux_syscalls, %r20, %r0 207 b,n .Lsyscall_nosys 208 209 LDREGX %r20(%r19), %r19 210 211 /* If this is a sys_rt_sigreturn call, and the signal was received 212 * when not in_syscall, then we want to return via syscall_exit_rfi, 213 * not syscall_exit. Signal no. in r20, in_syscall in r25 (see 214 * trampoline code in signal.c). 215 */ 216 ldi __NR_rt_sigreturn,%r2 217 comb,= %r2,%r20,.Lrt_sigreturn 218.Lin_syscall: 219 ldil L%syscall_exit,%r2 220 be 0(%sr7,%r19) 221 ldo R%syscall_exit(%r2),%r2 222.Lrt_sigreturn: 223 comib,<> 0,%r25,.Lin_syscall 224 ldil L%syscall_exit_rfi,%r2 225 be 0(%sr7,%r19) 226 ldo R%syscall_exit_rfi(%r2),%r2 227 228 /* Note! Because we are not running where we were linked, any 229 calls to functions external to this file must be indirect. To 230 be safe, we apply the opposite rule to functions within this 231 file, with local labels given to them to ensure correctness. */ 232 233.Lsyscall_nosys: 234syscall_nosys: 235 ldil L%syscall_exit,%r1 236 be R%syscall_exit(%sr7,%r1) 237 ldo -ENOSYS(%r0),%r28 /* set errno */ 238 239 240/* Warning! This trace code is a virtual duplicate of the code above so be 241 * sure to maintain both! */ 242.Ltracesys: 243tracesys: 244 /* Need to save more registers so the debugger can see where we 245 * are. This saves only the lower 8 bits of PSW, so that the C 246 * bit is still clear on syscalls, and the D bit is set if this 247 * full register save path has been executed. We check the D 248 * bit on syscall_return_rfi to determine which registers to 249 * restore. An interrupt results in a full PSW saved with the 250 * C bit set, a non-straced syscall entry results in C and D clear 251 * in the saved PSW. 252 */ 253 ldo -THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 /* get task ptr */ 254 LDREG TI_TASK(%r1), %r1 255 ssm 0,%r2 256 STREG %r2,TASK_PT_PSW(%r1) /* Lower 8 bits only!! */ 257 mfsp %sr0,%r2 258 STREG %r2,TASK_PT_SR0(%r1) 259 mfsp %sr1,%r2 260 STREG %r2,TASK_PT_SR1(%r1) 261 mfsp %sr2,%r2 262 STREG %r2,TASK_PT_SR2(%r1) 263 mfsp %sr3,%r2 264 STREG %r2,TASK_PT_SR3(%r1) 265 STREG %r2,TASK_PT_SR4(%r1) 266 STREG %r2,TASK_PT_SR5(%r1) 267 STREG %r2,TASK_PT_SR6(%r1) 268 STREG %r2,TASK_PT_SR7(%r1) 269 STREG %r2,TASK_PT_IASQ0(%r1) 270 STREG %r2,TASK_PT_IASQ1(%r1) 271 LDREG TASK_PT_GR31(%r1),%r2 272 STREG %r2,TASK_PT_IAOQ0(%r1) 273 ldo 4(%r2),%r2 274 STREG %r2,TASK_PT_IAOQ1(%r1) 275 ldo TASK_REGS(%r1),%r2 276 /* reg_save %r2 */ 277 STREG %r3,PT_GR3(%r2) 278 STREG %r4,PT_GR4(%r2) 279 STREG %r5,PT_GR5(%r2) 280 STREG %r6,PT_GR6(%r2) 281 STREG %r7,PT_GR7(%r2) 282 STREG %r8,PT_GR8(%r2) 283 STREG %r9,PT_GR9(%r2) 284 STREG %r10,PT_GR10(%r2) 285 STREG %r11,PT_GR11(%r2) 286 STREG %r12,PT_GR12(%r2) 287 STREG %r13,PT_GR13(%r2) 288 STREG %r14,PT_GR14(%r2) 289 STREG %r15,PT_GR15(%r2) 290 STREG %r16,PT_GR16(%r2) 291 STREG %r17,PT_GR17(%r2) 292 STREG %r18,PT_GR18(%r2) 293 /* Finished saving things for the debugger */ 294 295 ldil L%syscall_trace,%r1 296 ldil L%tracesys_next,%r2 297 be R%syscall_trace(%sr7,%r1) 298 ldo R%tracesys_next(%r2),%r2 299 300tracesys_next: 301 ldil L%sys_call_table,%r1 302 ldo R%sys_call_table(%r1), %r19 303 304 ldo -THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 /* get task ptr */ 305 LDREG TI_TASK(%r1), %r1 306 LDREG TASK_PT_GR20(%r1), %r20 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 316 317 comiclr,>>= __NR_Linux_syscalls, %r20, %r0 318 b,n .Lsyscall_nosys 319 320 LDREGX %r20(%r19), %r19 321 322 /* 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 333 334 /* Do *not* call this function on the gateway page, because it 335 makes a direct call to syscall_trace. */ 336 337tracesys_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 bl syscall_trace, %r2 344 STREG %r28,TASK_PT_GR28(%r1) /* save return value now */ 345 ldo -THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 /* get task ptr */ 346 LDREG TI_TASK(%r1), %r1 347 LDREG TASK_PT_GR28(%r1), %r28 /* Restore return val. */ 348 349 ldil L%syscall_exit,%r1 350 be,n R%syscall_exit(%sr7,%r1) 351 352.Ltrace_rt_sigreturn: 353 comib,<> 0,%r25,.Ltrace_in_syscall 354 ldil L%tracesys_sigexit,%r2 355 be 0(%sr7,%r19) 356 ldo R%tracesys_sigexit(%r2),%r2 357 358tracesys_sigexit: 359 ldo -THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 /* get task ptr */ 360 LDREG 0(%r1), %r1 361#ifdef CONFIG_64BIT 362 ldo -16(%r30),%r29 /* Reference param save area */ 363#endif 364 bl syscall_trace, %r2 365 nop 366 367 ldil L%syscall_exit_rfi,%r1 368 be,n R%syscall_exit_rfi(%sr7,%r1) 369 370 371 /********************************************************* 372 Light-weight-syscall code 373 374 r20 - lws number 375 r26,r25,r24,r23,r22 - Input registers 376 r28 - Function return register 377 r21 - Error code. 378 379 Scracth: Any of the above that aren't being 380 currently used, including r1. 381 382 Return pointer: r31 (Not usable) 383 384 Error codes returned by entry path: 385 386 ENOSYS - r20 was an invalid LWS number. 387 388 *********************************************************/ 389lws_start: 390 /* Gate and ensure we return to userspace */ 391 gate .+8, %r0 392 depi 3, 31, 2, %r31 /* Ensure we return to userspace */ 393 394#ifdef CONFIG_64BIT 395 /* FIXME: If we are a 64-bit kernel just 396 * turn this on unconditionally. 397 */ 398 ssm PSW_SM_W, %r1 399 extrd,u %r1,PSW_W_BIT,1,%r1 400 /* sp must be aligned on 4, so deposit the W bit setting into 401 * the bottom of sp temporarily */ 402 or,ev %r1,%r30,%r30 403 404 /* Clip LWS number to a 32-bit value always */ 405 depdi 0, 31, 32, %r20 406#endif 407 408 /* Is the lws entry number valid? */ 409 comiclr,>>= __NR_lws_entries, %r20, %r0 410 b,n lws_exit_nosys 411 412 /* WARNING: Trashing sr2 and sr3 */ 413 mfsp %sr7,%r1 /* get userspace into sr3 */ 414 mtsp %r1,%sr3 415 mtsp %r0,%sr2 /* get kernel space into sr2 */ 416 417 /* Load table start */ 418 ldil L%lws_table, %r1 419 ldo R%lws_table(%r1), %r28 /* Scratch use of r28 */ 420 LDREGX %r20(%sr2,r28), %r21 /* Scratch use of r21 */ 421 422 /* Jump to lws, lws table pointers already relocated */ 423 be,n 0(%sr2,%r21) 424 425lws_exit_nosys: 426 ldo -ENOSYS(%r0),%r21 /* set errno */ 427 /* Fall through: Return to userspace */ 428 429lws_exit: 430#ifdef CONFIG_64BIT 431 /* decide whether to reset the wide mode bit 432 * 433 * For a syscall, the W bit is stored in the lowest bit 434 * of sp. Extract it and reset W if it is zero */ 435 extrd,u,*<> %r30,63,1,%r1 436 rsm PSW_SM_W, %r0 437 /* now reset the lowest bit of sp if it was set */ 438 xor %r30,%r1,%r30 439#endif 440 be,n 0(%sr3, %r31) 441 442 443 444 /*************************************************** 445 Implementing CAS as an atomic operation: 446 447 %r26 - Address to examine 448 %r25 - Old value to check (old) 449 %r24 - New value to set (new) 450 %r28 - Return prev through this register. 451 %r21 - Kernel error code 452 453 If debugging is DISabled: 454 455 %r21 has the following meanings: 456 457 EAGAIN - CAS is busy, ldcw failed, try again. 458 EFAULT - Read or write failed. 459 460 If debugging is enabled: 461 462 EDEADLOCK - CAS called recursively. 463 EAGAIN && r28 == 1 - CAS is busy. Lock contended. 464 EAGAIN && r28 == 2 - CAS is busy. ldcw failed. 465 EFAULT - Read or write failed. 466 467 Scratch: r20, r28, r1 468 469 ****************************************************/ 470 471 /* Do not enable LWS debugging */ 472#define ENABLE_LWS_DEBUG 0 473 474 /* ELF64 Process entry path */ 475lws_compare_and_swap64: 476#ifdef CONFIG_64BIT 477 b,n lws_compare_and_swap 478#else 479 /* If we are not a 64-bit kernel, then we don't 480 * implement having 64-bit input registers 481 */ 482 b,n lws_exit_nosys 483#endif 484 485 /* ELF32 Process entry path */ 486lws_compare_and_swap32: 487#ifdef CONFIG_64BIT 488 /* Clip all the input registers */ 489 depdi 0, 31, 32, %r26 490 depdi 0, 31, 32, %r25 491 depdi 0, 31, 32, %r24 492#endif 493 494lws_compare_and_swap: 495#ifdef CONFIG_SMP 496 /* Load start of lock table */ 497 ldil L%lws_lock_start, %r20 498 ldo R%lws_lock_start(%r20), %r28 499 500 /* Extract four bits from r26 and hash lock (Bits 4-7) */ 501 extru %r26, 27, 4, %r20 502 503 /* Find lock to use, the hash is either one of 0 to 504 15, multiplied by 16 (keep it 16-byte aligned) 505 and add to the lock table offset. */ 506 shlw %r20, 4, %r20 507 add %r20, %r28, %r20 508 509# ifdef ENABLE_LWS_DEBUG 510 /* 511 DEBUG, check for deadlock! 512 If the thread register values are the same 513 then we were the one that locked it last and 514 this is a recurisve call that will deadlock. 515 We *must* giveup this call and fail. 516 */ 517 ldw 4(%sr2,%r20), %r28 /* Load thread register */ 518 /* WARNING: If cr27 cycles to the same value we have problems */ 519 mfctl %cr27, %r21 /* Get current thread register */ 520 cmpb,<>,n %r21, %r28, cas_lock /* Called recursive? */ 521 b lws_exit /* Return error! */ 522 ldo -EDEADLOCK(%r0), %r21 523cas_lock: 524 cmpb,=,n %r0, %r28, cas_nocontend /* Is nobody using it? */ 525 ldo 1(%r0), %r28 /* 1st case */ 526 b lws_exit /* Contended... */ 527 ldo -EAGAIN(%r0), %r21 /* Spin in userspace */ 528cas_nocontend: 529# endif 530/* ENABLE_LWS_DEBUG */ 531 532 LDCW 0(%sr2,%r20), %r28 /* Try to acquire the lock */ 533 cmpb,<>,n %r0, %r28, cas_action /* Did we get it? */ 534cas_wouldblock: 535 ldo 2(%r0), %r28 /* 2nd case */ 536 b lws_exit /* Contended... */ 537 ldo -EAGAIN(%r0), %r21 /* Spin in userspace */ 538#endif 539/* CONFIG_SMP */ 540 541 /* 542 prev = *addr; 543 if ( prev == old ) 544 *addr = new; 545 return prev; 546 */ 547 548 /* NOTES: 549 This all works becuse intr_do_signal 550 and schedule both check the return iasq 551 and see that we are on the kernel page 552 so this process is never scheduled off 553 or is ever sent any signal of any sort, 554 thus it is wholly atomic from usrspaces 555 perspective 556 */ 557cas_action: 558#if defined CONFIG_SMP && defined ENABLE_LWS_DEBUG 559 /* DEBUG */ 560 mfctl %cr27, %r1 561 stw %r1, 4(%sr2,%r20) 562#endif 563 /* The load and store could fail */ 5641: ldw 0(%sr3,%r26), %r28 565 sub,<> %r28, %r25, %r0 5662: stw %r24, 0(%sr3,%r26) 567#ifdef CONFIG_SMP 568 /* Free lock */ 569 stw %r20, 0(%sr2,%r20) 570# ifdef ENABLE_LWS_DEBUG 571 /* Clear thread register indicator */ 572 stw %r0, 4(%sr2,%r20) 573# endif 574#endif 575 /* Return to userspace, set no error */ 576 b lws_exit 577 copy %r0, %r21 578 5793: 580 /* Error occured on load or store */ 581#ifdef CONFIG_SMP 582 /* Free lock */ 583 stw %r20, 0(%sr2,%r20) 584# ifdef ENABLE_LWS_DEBUG 585 stw %r0, 4(%sr2,%r20) 586# endif 587#endif 588 b lws_exit 589 ldo -EFAULT(%r0),%r21 /* set errno */ 590 nop 591 nop 592 nop 593 nop 594 595 /* Two exception table entries, one for the load, 596 the other for the store. Either return -EFAULT. 597 Each of the entries must be relocated. */ 598 .section __ex_table,"aw" 599#ifdef CONFIG_64BIT 600 /* Pad the address calculation */ 601 .word 0,(2b - linux_gateway_page) 602 .word 0,(3b - linux_gateway_page) 603#else 604 .word (2b - linux_gateway_page) 605 .word (3b - linux_gateway_page) 606#endif 607 .previous 608 609 .section __ex_table,"aw" 610#ifdef CONFIG_64BIT 611 /* Pad the address calculation */ 612 .word 0,(1b - linux_gateway_page) 613 .word 0,(3b - linux_gateway_page) 614#else 615 .word (1b - linux_gateway_page) 616 .word (3b - linux_gateway_page) 617#endif 618 .previous 619 620end_compare_and_swap: 621 622 /* Make sure nothing else is placed on this page */ 623 .align ASM_PAGE_SIZE 624 .export end_linux_gateway_page 625end_linux_gateway_page: 626 627 /* Relocate symbols assuming linux_gateway_page is mapped 628 to virtual address 0x0 */ 629#ifdef CONFIG_64BIT 630 /* FIXME: The code will always be on the gateay page 631 and thus it will be on the first 4k, the 632 assembler seems to think that the final 633 subtraction result is only a word in 634 length, so we pad the value. 635 */ 636#define LWS_ENTRY(_name_) .word 0,(lws_##_name_ - linux_gateway_page) 637#else 638#define LWS_ENTRY(_name_) .word (lws_##_name_ - linux_gateway_page) 639#endif 640 641 .section .rodata,"a" 642 643 .align ASM_PAGE_SIZE 644 /* Light-weight-syscall table */ 645 /* Start of lws table. */ 646 .export lws_table 647.Llws_table: 648lws_table: 649 LWS_ENTRY(compare_and_swap32) /* 0 - ELF32 Atomic compare and swap */ 650 LWS_ENTRY(compare_and_swap64) /* 1 - ELF64 Atomic compare and swap */ 651 /* End of lws table */ 652 653 .align ASM_PAGE_SIZE 654 .export sys_call_table 655.Lsys_call_table: 656sys_call_table: 657#include "syscall_table.S" 658 659#ifdef CONFIG_64BIT 660 .align ASM_PAGE_SIZE 661 .export sys_call_table64 662.Lsys_call_table64: 663sys_call_table64: 664#define SYSCALL_TABLE_64BIT 665#include "syscall_table.S" 666#endif 667 668#ifdef CONFIG_SMP 669 /* 670 All light-weight-syscall atomic operations 671 will use this set of locks 672 */ 673 .section .data 674 .align 4096 675 .export lws_lock_start 676.Llws_lock_start: 677lws_lock_start: 678 /* lws locks */ 679 .align 16 680 .rept 16 681 /* Keep locks aligned at 16-bytes */ 682 .word 1 683 .word 0 684 .word 0 685 .word 0 686 .endr 687 .previous 688#endif 689/* CONFIG_SMP for lws_lock_start */ 690 691.end 692 693 694